bims-mitdis Biomed News
on Mitochondrial disorders
Issue of 2026–03–15
eighty-one papers selected by
Catalina Vasilescu, Helmholz Munich



  1. Hum Reprod. 2026 Mar 08. pii: deag020. [Epub ahead of print]
      Mitochondrial replacement therapies (MRTs) have been proposed as a means of avoiding the transmission of pathogenic mitochondrial DNA (mtDNA) mutations from mother to child. While clinical cases using this groundbreaking strategy have now been reported for the two principal MRT methods-pronuclear transfer and maternal spindle transfer-recent data continues to raise questions about the reliability of these approaches for disease prevention.
    Keywords:  female infertility; maternal spindle transfer; mitochondrial diseases; mitochondrial replacement therapies; mitochondrial reversal; oocyte quality; pronuclear transfer
    DOI:  https://doi.org/10.1093/humrep/deag020
  2. Cell. 2026 Mar 11. pii: S0092-8674(26)00173-X. [Epub ahead of print]
      Mitochondrial disease encompasses inherited disorders affecting mitochondrial function. A severe and untreatable form of mitochondrial disease is Leigh syndrome (LS), causing psychomotor regression and metabolic crises. To accelerate drug discovery for LS, we screen a library of 5,632 repurposable compounds in neural cells from LS-patient-derived induced pluripotent stem cells (iPSCs). We identify phosphodiesterase type 5 (PDE5) inhibitors as leads and prioritize sildenafil for its clinical safety. Sildenafil corrects mitochondrial membrane potential defects, restores neurodevelopmental pathways, and normalizes calcium responses in LS brain organoids. In small and large mammalian models of LS, sildenafil extends lifespan and ameliorates disease phenotypes. Off-label treatment on an individual basis with sildenafil in six LS patients improves their motor function and resistance to metabolic crises. Collectively, the findings highlight the potential of iPSC-driven drug discovery and position sildenafil as a promising drug candidate for mitochondrial disease.
    Keywords:  Leigh syndrome; PDE5 inhibitors; PRKG1; brain organoids; drug repurposing; drug screening; high-content analysis; iPSCs; mitochondrial diseases; sildenafil
    DOI:  https://doi.org/10.1016/j.cell.2026.02.008
  3. PLoS Genet. 2026 Mar;22(3): e1012076
      COG5, a subunit of the conserved oligomeric Golgi (COG) complex, plays a critical role in retrograde trafficking within the Golgi apparatus. Dysfunction of COG5 is associated with various human disorders, yet the underlying pathogenic mechanisms remain poorly understood. To investigate the mechanisms, we conducted proteomic analyses using COG5-deficient and rescue cell models, which revealed a potential link between COG5 dysfunction and mitochondrial oxidative phosphorylation (OXPHOS) deficiency. Using COG5-deficient cell models and patient-derived cells harboring COG5 variants, we biochemically validated the involvement of COG5 in mitochondrial OXPHOS, particularly in the regulation of complex I content. These models also exhibited elevated cellular copper levels. Notably, the significant reduction in OXPHOS complexes could be rescued by either restoring COG5 expression or administering a copper chelator. We further demonstrated that excessive cellular copper disrupts the function of mitochondrial iron-sulfur clusters, potentially leading to complex I assembly defects. Additionally, we identified a patient with biallelic COG5 variants presenting with a distinct subtype of mitochondrial disease (Leigh syndrome), a phenotype not previously associated with COG5-related disorders. These findings provide novel mechanistic insights into the role of COG5, extending beyond its established function in Golgi-mediated glycosylation modifications. Our results underscore the importance of COG5 in mitochondrial function through a copper-dependent pathway, offering new perspectives on its contribution to cellular homeostasis and disease pathogenesis.
    DOI:  https://doi.org/10.1371/journal.pgen.1012076
  4. Int J Mol Sci. 2026 Feb 26. pii: 2224. [Epub ahead of print]27(5):
      Mitochondrial dysfunction lies at the core of numerous cardiac pathologies, yet restoring mitochondrial health remains a therapeutic frontier. In recent years, extracellular vesicles (EVs) have emerged as nature's delivery nanocarriers, capable of transporting a wide array of biomolecules, including mitochondrial-associated microRNAs (mito-miRs). These miRNAs regulate bioenergetics, redox homeostasis, and apoptotic signaling-making them prime candidates for non-cellular mitochondrial therapy. This review explores the evolving landscape of mitochondrial miRNA encapsulation within EVs, focusing on their potential to restore mitochondrial transcriptional and metabolic programs governing ATP synthesis and redox balance, enhance cellular energy output, and mitigate oxidative stress. We integrate insights from stem cell biology, RNA epigenetics, systems cardiology, and bioengineering, offering a unifying framework for therapeutic applications across ischemic heart disease, heart failure, and chemotherapy-induced cardiomyopathy. An integrative narrative synthesis of recent peer-reviewed literature was performed across major biomedical databases, prioritizing mechanistic studies linking EV-mediated mito-miR delivery to cardiomyocyte mitochondrial function. By harmonizing multi-omic signaling, vesicle engineering, and mitochondrial medicine, this review seeks to guide future research toward targeted, customizable, and scalable bioenergetic interventions-unlocking a next-generation path for cardiovascular regeneration.
    Keywords:  RNA therapeutics; cardiomyocyte bioenergetics; extracellular vesicles (EVs); heart failure; miRNA engineering; mitochondrial microRNAs; non-cellular mitochondrial therapy; regenerative cardiology; systems biology; translational nanomedicine
    DOI:  https://doi.org/10.3390/ijms27052224
  5. Aging Dis. 2026 Mar 04.
      Mitochondria are increasingly recognized as central regulators of skin health and aging, providing ATP and coordinating redox signaling, mitophagy, and cell fate decisions. In cutaneous tissues, mitochondrial integrity sustains fibroblast-driven collagen synthesis, keratinocyte proliferation, melanocyte homeostasis, and efficient wound repair. With advancing age and cumulative ultraviolet exposure, mitochondria accumulate hallmark defects. Mitochondrial DNA mutations and deletions, impaired oxidative phosphorylation, excessive reactive oxygen species production, diminished mitophagy and biogenesis, disrupted fission-fusion dynamics, NAD⁺ decline, and sirtuin dysregulation all converge to undermine energy metabolism, amplify inflammatory signaling, and accelerate fibroblast senescence, extracellular matrix degradation, pigmentary changes, and delayed wound healing. Recent research also highlights weakened antioxidant defenses and extracellular vesicle-mediated propagation of mitochondrial stress across the cutaneous microenvironment, underscoring the organelle's central role in skin aging. Against this mechanistic backdrop, mitochondria-targeted interventions are emerging as promising therapeutic strategies. Extracellular vesicles loaded with NAD⁺ precursors, antioxidant enzymes, or mitophagy stimulators show preclinical efficacy in restoring bioenergetics and accelerating wound closure. Mitochondria-directed antioxidants such as melatonin and coenzyme Q10, NAD⁺ boosters and sirtuin activators, red and near-infrared photobiomodulation, and NRF2-based redox reprogramming each enhance mitochondrial homeostasis while improving collagen synthesis, pigmentation balance, and re-epithelialization. Early translational and clinical studies indicate that these approaches protect against UV-induced mitochondrial DNA damage, reduce oxidative stress, and improve cutaneous structure and function. Collectively, these findings position mitochondria as a modifiable hub for cutaneous aging and wound repair, and highlight the potential of integrated metabolic, antioxidant, and vesicle-based approaches to transform dermatologic anti-aging and wound-care interventions.
    DOI:  https://doi.org/10.14336/AD.2025.1585
  6. Trends Neurosci. 2026 Mar 11. pii: S0166-2236(26)00014-7. [Epub ahead of print]
      Mitochondria are energy- and metabolite-producing organelles that are differentially distributed throughout neuronal axons and dendrites to meet unique energy demands. Emerging evidence indicates that mitochondria in dendrites can be molecularly, structurally, and functionally distinct depending on cell types or even nearby synaptic inputs. This suggests that mitochondrial heterogeneity not only serves individual cell types but also plays a role in supporting the diversity of synaptic functions and connectivity patterns across different brain areas. This review highlights recent studies that contribute to our understanding of how heterogeneity in dendritic mitochondrial morphology, dynamics, and function converges to support cell- and compartment-specific metabolic demands and diverse postsynaptic properties.
    Keywords:  bioenergetics; brain; local translation; neuron; plasticity; postsynapse
    DOI:  https://doi.org/10.1016/j.tins.2026.01.011
  7. Mech Ageing Dev. 2026 Mar 05. pii: S0047-6374(26)00019-9. [Epub ahead of print]231 112167
      Mitochondria are central to cellular energy metabolism, redox balance, and signaling, and their integrity is maintained by a multilayered mitochondrial quality control (MQC) system. This system includes proteostasis, dynamics, biogenesis, and mitophagy, which together repair or remove damaged organelles. Mitochondria-derived vesicles (MDVs) have emerged as an additional MQC component. MDVs are small vesicles that bud from mitochondria and selectively transport damaged mitochondrial proteins, lipids, and nucleic acids to endolysosomal compartments or other intracellular destinations, enabling rapid and localized responses to mitochondrial stress. Acting upstream of or in parallel with mitophagy, MDVs can avoid or delay irreversible mitochondrial damage and help preserve cellular homeostasis. Aging and age-associated disorders are characterized by progressive mitochondrial dysfunction and chronic inflammation. Age-related changes in intracellular trafficking, lysosomal function, and vesicle dynamics may impair MDV formation, cargo selection, and targeting. Under conditions of defective degradation, mitochondrial components may also appear in extracellular vesicles, potentially contributing to altered intercellular signaling and inflammation. In the nervous system, where energetic demands are high and mitochondrial turnover requires tight regulation, such alterations may be especially harmful. This review summarizes MQC mechanisms in neurons, with a focus on MDVs, their dysregulation during aging and neurodegeneration, and implications for biomarkers and therapeutic strategies.
    Keywords:  Alzheimer’s disease; Huntington’s disease; Parkinson’s disease; Tau protein, α-synuclein
    DOI:  https://doi.org/10.1016/j.mad.2026.112167
  8. Mol Genet Metab. 2026 Mar 09. pii: S1096-7192(26)00150-2. [Epub ahead of print]148(2): 109867
      Isolated mitochondrial complex III deficiency can result from pathogenic variants in several nuclear or mitochondrial genes, encoding structural subunits or assembly factors of the enzyme. It is a rare cause of mitochondrial phenotypes with clinically heterogeneous presentations. Pathogenic variants in the Tetratricopeptide Repeat Domain 19 (TTC19) gene have been identified as a cause of mitochondrial complex III deficiency, nuclear type 2 (MIM #615157). We report 10 patients from five unrelated Arab families, all presenting with variable severity of a progressive neurodegenerative disorder characterized by loss of ambulation, speech impairment, and cognitive regression. Long-term clinical follow-up, supported by serial neuroradiological imaging, demonstrated progressive disease evolution, further highlighting the degenerative nature of the condition. In this cohort, exome sequencing (ES) identified three distinct pathogenic variants in the TTC19 gene across the five unrelated families, highlighting both genetic heterogeneity and regional clustering. In a Saudi family, A novel in-frame TTC19 variant NM_017775.4:c.680_709del; p.(Glu227_Leu236del) was identified, resulting in the loss of 10 amino acids in the protein. The second variant, NM_017775.4:c.779_780del; p.(Tyr260*), is a frameshift deletion leading to truncation of the TTC19 protein. This recurrent variant was identified in three independent Syrian families (Families 2, 3, and 4). The third variant, NM_017775.4:c.153_156del; p.(Arg52Alafs*48), also a frameshift variant, was detected in a fifth family of Kuwaiti origin. These loss of function TTC19 variants are proposed to underlie the observed phenotypes, as supported by mitochondrial functional studies, and contribute to the expanding spectrum of TTC19-related disorders, with specific variants recurring in particular regional or ethnic populations.
    Keywords:  Ataxia; Cognitive regression; Mitochondrial complex III deficiency; Mitochondrial respiratory chain complex III; Nuclear type 2 (MC3DN2); Progressive neurodegenerative disorder; Tetratricopeptide 19 (TTC19) gene
    DOI:  https://doi.org/10.1016/j.ymgme.2026.109867
  9. Exp Mol Med. 2026 Mar 13.
      Mitochondrial dysfunction is a critical driver of metabolic dysfunction-associated steatotic liver disease progression to steatohepatitis (MASH), yet the mechanisms governing mitochondrial quality control in hepatocytes remain poorly defined. Here we identify TANK-binding kinase 1 (TBK1) as an essential regulator of hepatic mitophagy and lysosomal activity. Using TBK1-deficient hepatocytes and liver-specific TBK1-knockout mice, we show that TBK1 loss leads to the accumulation of depolarized, reactive oxygen species-producing mitochondria due to impaired mitophagy flux, including defective lysosomal degradation. Mechanistically, TBK1 is required for p62 phosphorylation at Ser403 and partially modulates mTOR signaling to preserve lysosomal activity. Notably, both human samples and murine steatohepatitis models exhibited a substantial decline in TBK1 kinase activity. Therapeutic restoration of TBK1 expression via AAV8 delivery in MASH mouse model enhanced mitophagy, reduced mitochondrial burden and ameliorated liver fibrosis. Collectively, these findings establish TBK1 as a critical guardian of mitochondrial and lysosomal homeostasis in MASH.
    DOI:  https://doi.org/10.1038/s12276-026-01672-9
  10. Stem Cell Res. 2026 Mar 03. pii: S1873-5061(26)00044-9. [Epub ahead of print]93 103948
      Barth syndrome is among the most common mitochondrial diseases presenting with cardiomyopathy. We have generated a human embryonic stem cell (hESC) model of Barth syndrome (TAFAZZINΔ3 C15) in a female background (H9 hESC) using CRISPR/Cas9 gene editing, with compound heterozygous variants in TAFAZZIN that result in exon 3 skipping in all stable transcripts. This cell line displayed characteristics consistent with pluripotent stem cells, including typical colony morphology, expression of pluripotency markers, trilineage potential, and a normal karyotype. This TAFAZZINΔ3 C15 line could be used for investigation of disease mechanisms in mitochondrial cardiomyopathy and preclinical therapeutic screening.
    DOI:  https://doi.org/10.1016/j.scr.2026.103948
  11. Pediatr Neurol. 2026 Feb 13. pii: S0887-8994(26)00048-2. [Epub ahead of print]178 138-146
       BACKGROUND: Before diagnostic whole exome sequencing, monogenic/chromosomal developmental and epileptic encephalopathies (DEEs) were frequently misdiagnosed as mitochondrial disorders (MDs) with epilepsy, due to overlapping clinical and biochemical features. Assessing muscle functional assays in patients with a genetic diagnosis and epilepsy offers a unique opportunity to explore mitochondrial dysfunction in monogenic/chromosomal DEEs, in comparison to the mitochondrial dysfunction observed in genetically confirmed MDs.
    METHODS: In this retrospective cohort study, clinical and biochemical data were extracted from patients suspected of MD with epilepsy who underwent muscle/fibroblast biopsy (2005-2015). Patients were classified into four groups based on the final diagnosis. Mitochondrial Disease Criteria scores were assigned. Statistical analyses were conducted using Fisher's exact, analysis of variance, and Kruskal-Wallis tests.
    RESULTS: Of 27 included participants, eleven (40.7%) had DEEs, four (14.8%) had genetically confirmed MDs, eight (29.6%) were suspected MD cases without genetic confirmation, and four (14.8%) had nonmitochondrial metabolic diseases. Mitochondrial dysfunction was common across all groups; 85% of participants met probable/definite Mitochondrial Disease Criteria, over 70% had elevated plasma lactate (>2.5 mmol/L), and 92% exhibited impaired adenosine triphosphate production. Surprisingly, moderate to severe complex dysfunction was observed in all groups except genetically confirmed MDs.
    CONCLUSIONS: Our findings indicate that mitochondrial dysfunction is prevalent in nonmitochondrial DEEs. Patients previously diagnosed with an MD based only on muscle/fibroblast biopsy may benefit from whole exome sequencing to identify genetic variants, for which targeted therapy may be available. Future research should explore whether treatment or prognosis of nonmitochondrial DEEs should be tailored to improve mitochondrial function.
    Keywords:  DEE; Developmental and epileptic encephalopathies; Genetic epilepsy; Mitochondrial disease; Mitochondrial dysfunction; Muscle functional assay; Seizures
    DOI:  https://doi.org/10.1016/j.pediatrneurol.2026.02.004
  12. Cell Rep. 2026 Mar 06. pii: S2211-1247(26)00104-X. [Epub ahead of print]45(3): 117026
      Endogenous (self) double-stranded RNAs (dsRNAs) in human cells can activate innate immune responses. ADAR1, an A-to-I editing enzyme of dsRNAs, suppresses aberrant immune activation by self-dsRNAs. However, how ADAR1 influences the cellular dsRNA landscape remains unclear. We show that human ADAR1 downregulates self-dsRNA abundance through editing-dependent and editing-independent mechanisms. We further conducted quantitative dsRNA sequencing on wild-type and ADAR1-deficient cells. dsRNAs are enriched in protein-coding mRNAs-especially those with repetitive elements and elongated 3' UTRs-and mitochondrial RNAs. ADAR1-regulated dsRNA transcripts consist of nuclear-encoded mRNAs and, unexpectedly, mitochondria-encoded RNAs rarely edited by ADAR1. Accordingly, dsRNAs accumulate to high levels within the mitochondria of ADAR1-deficient cells. Mass spectrometry and biochemical assays can detect ADAR1p150 in mitochondrial fractions. Notably, ADAR1 loss sensitizes cells to inflammation under mitochondrial stress (e.g., herniation and X-ray irradiation). Hence, we show that dsRNAs regulated by ADAR1 go beyond A-to-I edited transcripts and that ADAR1 can control mitochondrial dsRNAs.
    Keywords:  A-to-I editing; ADAR1; AGS; Aicardi-Goutieres syndrome; CP: immunology; CP: molecular biology; IFN; PKR; double-stranded RNA; dsRNA; dsRNA-seq; innate immunity; mitochondria; mitochondrial stress; protein kinase R; type 1 interferon
    DOI:  https://doi.org/10.1016/j.celrep.2026.117026
  13. Nat Commun. 2026 Mar 12.
      Mosaic variegated aneuploidy (MVA), a rare human congenital disorder that causes microcephaly, is characterized by extensive abnormalities in chromosome number and results from mutations in genes involved in accurate mitotic chromosome segregation. To characterize the cellular mechanisms underlying this disease, here we generated a Drosophila model of microcephaly caused by the depletion of a single spindle assembly checkpoint (SAC) gene in the neural stem cell (NSC) compartment. We present evidence that loss of stemness - compromised identity and proliferative capacity of NSCs- plays an important role in MVA and results in a reduced number of neurons and glial cells. We show that loss of stemness arises from the accumulation over time of an unbalanced number of gains and losses of more than one chromosome, rather than a direct consequence of chromosomal instability-induced DNA damage or the production of simple aneuploidies. We unravel a contribution of proteostasis failure and mitochondrial dysfunction to the negative impact of complex aneuploidies on stemness, a highly energy demanding cellular state. We identify overexpression of Radical Oxygen Species scavengers, mitochondria chaperones and apoptosis inhibition as genetic interventions capable of dampening the deleterious effects of aneuploidy on brain size.
    DOI:  https://doi.org/10.1038/s41467-026-70521-0
  14. Trends Endocrinol Metab. 2026 Mar 07. pii: S1043-2760(26)00034-2. [Epub ahead of print]
      Mitochondria play a central role in energy metabolism, redox balance, and cellular homeostasis, and their dysfunction has been implicated in the pathogenesis of complex human diseases. Advances in systems biology and omics technologies have elucidated the mechanisms underlying these conditions, including metabolic dysfunction, mitochondrial impairment, inflammation, and redox imbalance. Preclinical and early clinical studies of combined metabolic activators (CMA), a formulation of bioactive metabolites, have demonstrated improvements in mitochondrial function and systemic metabolic profiles across multiple diseases. In this review, we provide a comprehensive overview of the mechanistic rationale for CMA, summarize evidence from preclinical models and clinical studies investigating CMA and its components, and evaluate its translational potential and challenges as a mitochondrial-targeted therapeutic strategy for complex human diseases.
    Keywords:  NAD(+); combined metabolic activators; glutathione; l-carnitine tartrate; metabolic diseases; mitochondrial dysfunction; serine
    DOI:  https://doi.org/10.1016/j.tem.2026.01.018
  15. Sci Adv. 2026 Mar 13. 12(11): eadz3266
      Sepsis-induced cardiac dysfunction arises from complex intercellular communication networks that extend beyond direct cardiomyocyte damage, yet the nanoscale mechanisms governing these interactions remain poorly understood. Here, we identify tunneling nanotubes (TNTs) as dynamic biological nanostructures facilitating intercellular mitochondrial transfer, revealing their critical role in septic cardiac remodeling. Using a murine cecal ligation and puncture (CLP) model and single-cell RNA sequencing, we demonstrate that sepsis reprograms cardiac endothelial cells, fibroblasts, and macrophages, generating metabolically impaired subpopulations with dysfunctional mitochondrial respiration. We uncover a Drp1-driven cytoskeletal remodeling process that orchestrates TNT biogenesis, wherein Drp1 interacts with Filamin and Kinesin to regulate TNT formation and extension, enabling long-range organelle trafficking. Cardiac-specific Drp1 knockout disrupts TNT-mediated mitochondrial exchange, halting metabolic deterioration and reversing cellular reprogramming. These findings establish Drp1-mediated TNT networks as nanoscale conduits of organelle communication, offering insights into biological nanotube engineering, cellular-scale nanotechnology, and potential therapeutic interventions for mitochondrial dysfunction in sepsis.
    DOI:  https://doi.org/10.1126/sciadv.adz3266
  16. Neurol Genet. 2026 Apr;12(2): e200365
       Background and Objectives: POLG-related disorders exhibit marked phenotypic heterogeneity and frequent clinical overlap, often leading to delayed diagnosis. A precise delineation of their clinical spectrum, natural history, and the identification of reliable biomarkers is essential to improve diagnostic accuracy and guide therapeutic development.
    Methods: We analyzed a cohort of 34 patients with confirmed pathogenic POLG variants, assessing clinical phenotypes, molecular findings, and biomarkers (plasma growth differentiation factor-15 [GDF15] in 16, plasma neurofilament light chain [NF-L] in 14, and mitochondrial DNA [mtDNA] copy number in muscle in 16).
    Results: Thirty four patients (0.6-71 years) from 33 families were included. Juvenile/adult onset (12-40 years) was the most common presentation (62%). The predominant phenotypic categories were ataxia-neuropathy spectrum ([ANS], 44%), autosomal recessive PEO-plus (arPEO-plus, 26%), and autosomal dominant PEO-plus ([adPEO-plus], 15%), with frequent phenotypic overlap. Recessive inheritance accounted for 74% of cases, with the most common variants being p.([Thr251Ile; Pro587Leu]) paired on 1 allele, p.(Ala467Thr), and p.(Trp748Ser). Dominant variants were associated with milder, primarily myopathic phenotypes. The most common dominant variant was p.(Tyr955Cys). No clear genotype-phenotype correlations were identified among recessive variants. Compared with previously reported cohorts, our patients exhibited a lower prevalence of seizures, hepatopathy, and stroke-like episodes. GDF15 was elevated in 87.5% of patients, with a mean level of 3,315 pg/mL (±1,559.79), showing no significant differences between myopathic and ANS phenotypes, supporting its role as a general biomarker of mitochondrial dysfunction. NF-L was elevated in 78.6% of tested individuals but did not correlate with phenotype or clinical severity (as per Newcastle Mitochondrial Disease Adult Scale score).On average, muscle mtDNA copy number in patients was 76% of that observed in controls, with no differences by phenotype or inheritance pattern. All but 1 patient exhibited multiple mtDNA deletions, likely representing the primary mechanism of oxidative phosphorylation dysfunction rather than mtDNA depletion.
    Discussion: POLG-related disorders demonstrate extensive clinical variability with no consistent genotype-phenotype correlation. GDF15 and NF-L may serve as useful, though nonspecific, biomarkers of mitochondrial and neuroaxonal dysfunction, respectively. Prospective studies incorporating advanced molecular profiling are essential to establish reliable outcome measures and inform future therapeutic strategies.
    DOI:  https://doi.org/10.1212/NXG.0000000000200365
  17. Mol Neurobiol. 2026 Mar 11. pii: 493. [Epub ahead of print]63(1):
      Alzheimer's disease (AD) is a progressive neurodegenerative disorder marked by memory loss and cognitive decline, predominantly in the elderly (Alzheimer Disease International et al., 2015). Although amyloid-β peptide (Aβ), particularly in its oligomeric forms, has long been linked to AD pathogenesis (Chen 9:1205-1235 2017, Gaspar 2 394-400 2010), the mechanisms underlying its cellular toxicity remain unclear. Mitochondrial dysfunction is a consistent feature of AD (D'Alessandro 107:102713 2025), yet how Aβ drives these alterations is not fully understood. This review integrates recent evidence showing that Aβ accumulates on mitochondrial membranes (Cenini 21:3257-3272 2016, Manczak 23:5131-5146 2006, Sirk 5:1989-2003 2007), providing a mechanistic link between amyloid pathology and mitochondrial damage. We discuss how membrane-associated Aβ disrupts mitochondrial protein import by impairing the translocase of the outer membrane (TOM) complex (Cenini 21:3257-3272 2016, Sirk 5:1989-2003 2007) and interferes with voltage-dependent anion channel 1 (VDAC1) (Smilansky 52:30670-30683 2015), a key regulator of metabolite exchange and apoptosis. We further emphasize the role of mitochondria-associated membranes (MAMs) as critical sites for Aβ generation and transfer to mitochondria, where dysregulated cholesterol metabolism may amplify MAM activity and Aβ accumulation (Area-Gomez and Schon 38:90-96 2017, Monaghan 2:240287 2025). Altogether, we propose that mitochondrial membrane localization of Aβ is a central mechanism linking amyloid pathology to mitochondrial dysfunction in aging, highlighting new directions for mitochondria-targeted therapeutic strategies in AD.
    Keywords:  Amyloid-β; Cholesterol; Mitochondria; Mitochondria-associated membranes; Proteostasis; Translocase of outer membrane; Voltage-dependent anion channel
    DOI:  https://doi.org/10.1007/s12035-026-05786-z
  18. Ann Neurol. 2026 Mar 11.
       OBJECTIVE: Cerebral ischemic stroke causes neuronal oxygen/energy deprivation, disrupting mitochondrial function including reduced membrane potential and bioenergetics, exacerbating neuronal injury. Mitochondrial defects are, therefore, a central neuropathological node and potential therapeutic target. Previous studies have shown that mitochondria transplantation rescued infarction in cerebral ischemic stroke. However, interactions between transplanted and endogenous mitochondria remain unclear. Here, we proposed astrocytic mitochondria as the optional donor for mitochondria transplantation in ischemic stroke treatment because of their ischemic resistance.
    METHODS: We transplanted mitochondria derived from astrocytes into an ischemic stroke cell and mouse model to investigate the feasibility and mechanisms of astrocytic mitochondria transplantation for ischemic cerebral stroke. We assessed the uptake of transplanted mitochondria by neurons, their impact on endogenous mitochondrial dynamics (fusion/fission), mitochondrial functions, neuronal dendritic structure, neuronal survival, and mice motor function.
    RESULTS: Transplanted astrocytic mitochondria were successfully taken up by neurons, and within neurons, they flexibly regulated endogenous mitochondrial dynamics. This intervention rescued the stroke-induced reduction in mitochondrial membrane potential and oxidative phosphorylation capacity. Consequently, it significantly decreased neuronal dendritic injuries and cell death. These cellular improvements translated into alleviated motor deficits in the stroke model.
    INTERPRETATION: Astrocytic mitochondria transplantation is an effective therapeutic strategy for ischemic stroke. Its neuroprotective effects stem from the internalization of functional mitochondria into neurons and the subsequent flexibly regulation of endogenous mitochondrial dynamics, restoring bioenergetics and promoting neuronal survival. This approach holds significant promise for treating ischemic stroke and potentially other brain disorders involving mitochondrial dysfunction. ANN NEUROL 2026.
    DOI:  https://doi.org/10.1002/ana.78197
  19. Cureus. 2026 Feb;18(2): e103261
      Leber hereditary optic neuropathy (LHON) is an inherited mitochondrial optic neuropathy characterized by acute or subacute painless central visual loss. Most cases are associated with three primary mitochondrial DNA mutations; however, rare variants remain incompletely characterized. Early diagnosis is essential for appropriate management and genetic counseling. We report the case of a 51-year-old Lithuanian woman who presented with painless, progressive central visual loss. Initial neurological and ophthalmological investigations were unremarkable, and corticosteroid therapy was ineffective. Genetic testing revealed a rare homoplasmic m.3394T>C mutation in the MT-ND1 gene. The patient was subsequently treated with idebenone and followed for six years. Following initiation of idebenone therapy, the patient demonstrated gradual and sustained improvement in best-corrected visual acuity, reaching 1.0 in both eyes. Visual fields stabilized, and long-term follow-up showed preserved visual function. Optical coherence tomography revealed persistent but stable structural changes, including retinal nerve fiber layer and ganglion cell layer thinning in the affected eye. This case highlights the potential for favorable long-term visual outcomes in patients with LHON associated with rare mitochondrial variants. It underscores the importance of considering hereditary optic neuropathy in patients with painless visual loss and poor response to corticosteroids. Further studies are needed to clarify genotype-phenotype correlations and treatment responsiveness in rare LHON-associated mutations.
    Keywords:  aetiology; diagnosis; leber hereditary optic neuropathy; mt-nd1 gene (m.3394t>c); treatment
    DOI:  https://doi.org/10.7759/cureus.103261
  20. J Physiol. 2026 Mar 10.
      Mitochondria are diverse and multifaceted intracellular organelles regulating oxidative energy supply, lipid metabolism and calcium (Ca2+) signalling. In neurons the spatial sequestration of cytoplasmic Ca2+ by mitochondria plays a critical role in determining activity-dependent spine plasticity, shaping the presynaptic transmitter release characteristics and contributing to sustained action potential firing. Here, we tested the hypothesis that mitochondria at the axon initial segment (AIS) affect the microdomain cytoplasmic Ca2+ transients, thereby regulating Ca2+-dependent voltage-gated ion channels at the plasma membrane and initiation of action potentials. Using 3D electron microscopy reconstructions and virally injecting genetically encoded fluorescence indicators we visualized the ultrastructure and distribution of mitochondria selectively in thick-tufted layer 5 pyramidal neurons. We found that most mitochondria were stably clustered to the proximal AIS, while few were observed at distal sites. Simultaneous two-photon imaging of action potential-dependent cytoplasmic and mitochondrial Ca2+, combined with electrophysiological recordings showed that AIS mitochondria exhibit powerful activity-dependent cytosolic Ca2+ uptake. However, while intracellular application of the mitochondrial Ca2+ uniporter inhibitor Ru360 fully blocked mitochondrial Ca2+ import and increased the slow afterhyperpolarization duration, it did not affect action potential input-output function, action potential dynamics nor the ability to produce high-frequency burst output. Together, the results indicate that AIS mitochondria are dispensable for temporal and rate encoding, suggesting that mt-Ca2+ buffering at the AIS may be involved in non-electrical roles. KEY POINTS: Mitochondrial Ca2+ buffering controls multiple Ca2+-dependent intracellular processes and their subcellular location of the organelles defines local physiological properties in neurons. Recent studies implicate mitochondrial Ca2+ uptake in the slow afterhyperpolarization and maintenance of action potential firing. Using electron microscopy and virally delivered genetically encoded tools we examined mitochondria in the layer 5 pyramidal neuron axon initial segment (AIS), the site where action potentials initiate, and found that cytoplasmic Ca2+ influx is powerfully buffered by proximally clustered mitochondria. Electrophysiological recordings during the block of the mitochondrial calcium uniporter reveal a role in the slow afterhyperpolarization, while AIS action potential initiation and action potential waveforms are independent from mitochondria. These findings indicate AIS mitochondria under physiological conditions exert non-electrical roles.
    Keywords:  action potential; axon initial segment; calcium buffer; mitochondria; pyramidal neuron
    DOI:  https://doi.org/10.1113/JP289290
  21. Hum Reprod. 2026 Mar 13. pii: deag027. [Epub ahead of print]
      Maternal spindle transfer (MST) and pronuclear transfer (PNT) raise a number of important ethical and regulatory issues. These IVF procedures that transfer nuclear DNA to enucleated oocytes or zygotes aim to prevent transmitting mitochondrial disease by female carriers of mitochondrial DNA (mtDNA) mutations and enable them to have healthy genetically related children. MST/PNT might also prove effective in treating oocyte-related infertility, but are not permitted in the UK and Australia, unlike MST/PNT for mtDNA disorders. The paper discusses the regulation of MST/PNT for both applications in relation to their risks and efficacy, highlighting the scarcity of clinical data. Based on risk reduction, it has even been proposed to treat oocyte-related infertility first before moving to mtDNA disorders. We argue that a prohibition of MST/PNT for infertility is not justified, neither should it initially be applied only for infertility because of the little evidence yet available regarding its efficacy and potential risks. We propose a staged approach to identify MST/PNT-treatable causes of oocyte-related infertility first, followed by a preclinical study and clinical trial and, if positive, wider application. Importantly, we call for transparency in publishing regular trial results, deeper ethical reflection, and more consistent policies that consider comparable uncertainties in mtDNA disorders and oocyte-related infertility.
    Keywords:  assisted reproduction; ethics; maternal spindle transfer; mitochondria; mitochondrial DNA disorders; mitochondrial donation; nuclear transfer; oocyte-related infertility; pronuclear transfer; translational research
    DOI:  https://doi.org/10.1093/humrep/deag027
  22. Nat Commun. 2026 Mar 13.
      Mitochondrial diseases progressively lead to multisystemic failure with treatment options remaining extremely limited. Here, to investigate strategies that alleviate mitochondrial dysfunction, we first generate a ubiquitous and tamoxifen-inducible knockout mouse model of mitochondrial transcription factor A (TFAM), a nuclear-encoded protein involved in mitochondrial DNA (mtDNA) maintenance - Tfamfl/flUbcCre-ERT2 (iTfamKO) mice. Systemic TFAM deficiency triggers mitochondrial decline in a myriad of tissues in adult mice. Consequently, iTfamKO mice manifest multiorgan dysfunction including lipodystrophy, sarcopenia, metabolic alterations, kidney failure, neurodegeneration, and locomotor dysregulation, which result in the premature death of these mice. Interestingly, iTfamKO mice display intestinal barrier disruption and gut dysbiosis, with diminished levels of microbiota-derived short-chain fatty acids (SCFAs), such as butyrate. Mice with a deficient proof-reading version of the mtDNA polymerase gamma (mtDNA-mutator mice) phenocopy the dysfunction of the intestinal barrier and bacterial dysbiosis with reduced levels of butyrate, suggesting that different mouse models of mitochondrial dysfunction share insufficient generation of butyrate. Transfer of microbiota from healthy control mice or administration of tributyrin, a butyrate precursor, delay multiple signs of multimorbidity, extending lifespan in iTfamKO mice. Mechanistically, butyrate supplementation recovers epigenetic histone acylation marks that are lost in the intestine of Tfam deficient mice. Overall, our findings highlight the relevance of preserving host-microbiota symbiosis in disorders related to mitochondrial dysfunction.
    DOI:  https://doi.org/10.1038/s41467-026-70547-4
  23. Cell Mol Life Sci. 2026 Mar 07.
      Mitochondrial metabolism is fundamental to cardiac and skeletal muscle function due to the high adenosine triphosphate (ATP) demand required for sustained contractility. Although mitochondrial dysfunction is central to metabolic myopathies, the epigenetic mechanisms regulating mitochondrial structure and function remain poorly defined. Here, we identify the SWI/SNF chromatin remodeling ATPase subunit Smarca4 as a critical regulator of mitochondrial homeostasis and cellular energy metabolism. Using a smarca4a-deficient zebrafish model (smarca4aa8-/-), we show that Smarca4 loss causes ventricular hypoplasia, pericardial edema, and disorganized skeletal muscle, leading to pronounced impairment of cardiac and muscular function. Heart-specific RNA-seq, ATAC-seq, and single-cell RNA-seq analyses revealed that Smarca4 deficiency reduces chromatin accessibility and suppresses the transcription of genes controlling mitochondrial biogenesis and oxidative phosphorylation. Consistently, high-resolution confocal imaging and Seahorse-based metabolic profiling demonstrated marked reductions in mitochondrial content, respiratory capacity, and ATP generation. AAV-mediated SMARCA4 knockdown in human cardiomyocytes and murine myotubes reproduced these mitochondrial defects. Collectively, these findings establish Smarca4 as a conserved chromatin remodeling factor linking nuclear regulation to mitochondrial energy homeostasis during vertebrate muscle development.
    Keywords:  ATP; Heart; Mitochondrial respiration; SMARCA4; SWI/SNF complex; Skeletal muscle
    DOI:  https://doi.org/10.1007/s00018-026-06168-3
  24. Trends Endocrinol Metab. 2026 Mar 10. pii: S1043-2760(26)00033-0. [Epub ahead of print]
      Heme availability shapes mitochondrial function, redox balance, and innate immune signaling. Recent studies reveal threshold-dependent heme states that predispose cells to cuproptosis, ferroptosis, apoptosis, pyroptosis, or PANoptosis. Viewing heme as a metabolic rheostat provides a unifying framework for interpreting regulated cell death across cancer, infection, and metabolic disease.
    Keywords:  damage-associated molecular pattern signaling; heme metabolism; immunometabolism; mitochondrial stress; regulated cell death
    DOI:  https://doi.org/10.1016/j.tem.2026.01.017
  25. Cell. 2026 Mar 09. pii: S0092-8674(26)00161-3. [Epub ahead of print]
      The regulation of nicotinamide adenine dinucleotide (NAD+) is crucial for numerous life processes. However, the mechanisms leading to NAD+ degradation in mitochondria remain insufficiently defined. Through in silico screening of potential NAD-binding proteins, we discovered a mitochondrial reaction in which NAD+ is hydrolyzed to nicotinamide mononucleotide (NMN) and AMP by SELENOO (SelO), using Mn2+ as cofactor. Catalysis depends on SelO's selenocysteine-serine-serine (CSS) C-terminal residues, particularly the selenocysteine 667. In addition to broad metabolic effects, this reaction plays a pronounced role in lipid utilization via SelO directly associating with fatty acid oxidation (FAO) enzymes, and it is conserved in both mammalian cells and bacteria. This reaction is responsive to elevated matrix pH, a signal of enhanced mitochondrial respiration, and protects mitochondria from sustained metabolic overactivation. These findings reveal a conserved mechanism for spatiotemporal NAD+ regulation and highlight its physiological significance in both prokaryotes and eukaryotes.
    Keywords:  NAD; fatty acid oxidation; hydrolysis reaction; mitochondrial homeostasis; nicotinamide adenine dinucleotide; selenocysteine
    DOI:  https://doi.org/10.1016/j.cell.2026.01.033
  26. Biol Pharm Bull. 2026 ;49(3): 457-466
      Mitochondria are essential organelles responsible for energy production, autophagy, and apoptosis, and mitochondrial dysfunction has been implicated in various diseases affecting the heart, liver, and kidneys. Mitochondrial transplantation, wherein isolated mitochondria are administered into cells or tissues, has recently emerged as a promising therapeutic approach for restoring cellular functions by enhancing ATP generation and reducing oxidative stress. However, the characteristics and functional diversity of the mitochondria isolated from different cell types remain poorly understood. Here, we aimed to identify the optimal mitochondrial source for transplantation therapy by comparing mitochondria isolated from several mammalian cell types, including mesenchymal stromal, hepatic, muscular, and pluripotent stem cells. Mitochondria were isolated using a streptolysin O-based isolation method and characterized through particle size, zeta potential, protein content, and ATP content. The isolated mitochondria exhibited uniform morphology, negative surface charge, sufficient protein yield, and ATP content, indicating successful preparation of functionally competent organelles suitable for comparative analysis. The mitochondria derived from mesenchymal stromal cells exhibited the highest bioenergetic activity. Adding these mitochondria enhanced cellular proliferation, oxygen consumption, and resistance to oxidative stress in recipient cells. Collectively, these findings demonstrate that mitochondria isolated from autologous mesenchymal stromal cells possess superior bioenergetic properties, highlighting their potential as an optimal source for mitochondrial transplantation therapy and providing new insights into the design of mitochondria-based therapeutics.
    Keywords:  ATP production; cellular bioactivity; mesenchymal stromal cell; mitochondrial transplantation; oxidative stress
    DOI:  https://doi.org/10.1248/bpb.b25-00716
  27. Int J Mol Sci. 2026 Mar 03. pii: 2361. [Epub ahead of print]27(5):
      Mitochondria play a crucial role in cellular bioenergetics, signaling, and metabolism; yet, many fundamental mechanisms such as the proton transfer along the membranes, the link between membrane curvature and oxidative phosphorylation, and the nanoscale organization of enzyme supercomplexes remain poorly understood due to the limitations of classical biochemical approaches. This review addresses this gap by systematically analyzing the contemporary physical methods used to investigate the mitochondrial structure and function from the micro to nano scale. It covers advanced fluorescence and super-resolution microscopy, electron and volume electron microscopy, and scanning probe techniques, as well as cryo-electron tomography for resolving supramolecular assemblies in near-native conditions. The review highlights the applications of the modern fluorescent probes, expansion and phase microscopy, and machine-learning-based image analysis for a quantitative assessment of the mitochondrial morphology, membrane potential, and dynamics in living cells and tissues. Complementary spectroscopic and scattering methods, including Raman spectroscopy, NMR, and X-ray and neutron scattering, are discussed as tools for probing the redox state, metabolite composition, and membrane organization. Emphasis is placed on integrating high-resolution experimental data with advanced computational frameworks to test competing models of mitochondrial function and pathology, and to guide the development of biomimetic and biomedical technologies.
    Keywords:  bioenergetics; cryo-electron tomography; fluorescent markers; mitochondria; mitochondrial morphology; spectroscopy; super-resolution
    DOI:  https://doi.org/10.3390/ijms27052361
  28. Redox Biol. 2026 Mar 02. pii: S2213-2317(26)00104-7. [Epub ahead of print]92 104106
      Mitochondrial dysfunction is a central driver of irreversible neuronal injury following ischemic stroke (IS); yet effective strategies to restore mitochondrial function and promote long-term neurological recovery remain limited. In this study, we demonstrate that mitochondrial extracellular vesicles derived from human umbilical cord mesenchymal stem cells (hUCMSC Mito-EVs) serve as a novel biotherapeutic vehicle capable of delivering functional mitochondria to damaged neurons. This process involves Target of Myb1-like 2 membrane trafficking protein (Tom1l2)-dependent membrane fusion between hUCMSC Mito-EVs and neuronal mitochondria, leading to the restoration of mitochondrial membrane potential and mitochondrial function. Mechanistically, Mito-EVs-mediated mitochondrial transfer upregulates cardiolipin synthase 1 (CRLS1), which preserves the inner mitochondrial membrane integrity and stabilizes respiratory chain complexes. The restoration of mitochondrial structure and function subsequently reduces reactive oxygen species production, suppresses pyroptosis, and promotes the recovery of neuronal metabolic and functional homeostasis. Collectively, these findings suggest that the Tom1l2-Crls1 axis serves as a key mediator of mitochondrial repair in hUCMSC Mito-EVs therapy, highlighting its promising potential as a targeted therapeutic strategy for neuronal protection following IS.
    Keywords:  Human umbilical cord mesenchymal stem cells; Ischemic stroke; Mitochondria; Mitochondrial extracellular vesicles; Neuron
    DOI:  https://doi.org/10.1016/j.redox.2026.104106
  29. Mol Genet Metab. 2026 Mar 03. pii: S1096-7192(26)00158-7. [Epub ahead of print]148(2): 109875
       BACKGROUND: Primary mitochondrial diseases (PMD) are rare heterogeneous disorders caused by defective oxidative phosphorylation, with symptoms varying widely between individuals with PMD. Despite extensive research, no consensus exists on outcome measures that adequately reflect function, activities, and participation for adults with mitochondrial diseases. The Goal Attainment Scale (GAS) offers a personalized, patient-centered way to capture these outcomes. However, its validity and standardized use in trials remain unclear. This study assessed GAS construct validity in a PMD trial, including comparison with the Canadian Occupational Performance Measure (COPM), and provides guidance for future application.
    METHODS: Data from a double-blind, randomized, placebo-controlled, exploratory Phase IIA cross-over trial on the safety and efficacy of sonlicromanol (KH176) in 18 adult m.3243 A>G patients, were retrospectively analyzed. GAS goals were categorized using the World Health Organization International Classification of Functioning, Disability and Health. Additional outcome measures with overlapping content were selected to evaluate GAS validity. Implementation quality was evaluated using 17 GAS appraisal criteria.
    RESULTS: Most goals addressed fatigue or lack of energy (85%, 22/26). GAS showed weak to moderate negative correlations with the Checklist Individual Strength (CC = -0.40) and Beck Depression Inventory-II scores (CC = -0.37), indicating higher GAS scores were associated with reductions in fatigue and depressive symptoms. Moderate correlations were observed between GAS and COPM scores (CC = 0.50-0.55). No significant correlations were found with the 6-min walk test, 36-item Short Form Health Survey or Newcastle Mitochondrial Disease Scale for Adults. Only 6 out of 17 (35%) implementation criteria were fully met.
    CONCLUSIONS: GAS demonstrated some construct validity in relation to fatigue and depressive symptoms, showed limited overlap with conventional outcome measures and suffered from suboptimal implementation. Although exploratory, these findings suggest GAS may capture patient-relevant change in individuals with PMD. To realize its potential, standardized methodology and further validation are essential for its use as a robust outcome measure in future PMD trials.
    Keywords:  Construct validity; Goal attainment scale; Mitochondrial disease; Outcome measure
    DOI:  https://doi.org/10.1016/j.ymgme.2026.109875
  30. Mech Ageing Dev. 2026 Mar 09. pii: S0047-6374(26)00026-6. [Epub ahead of print]231 112174
      The increasing global burden of age-related diseases necessitates interventions that target the unified biological processes of aging, as outlined by the expanding framework of fourteen interconnected hallmarks. This review establishes nicotinamide adenine dinucleotide (NAD⁺) as the central metabolic hub that coordinately regulates this entire network. We systematically elucidate the bidirectional mechanistic links between NAD⁺ metabolism and each hallmark, demonstrating how its age-related decline-driven by impaired biosynthesis and heightened consumption-propagates dysfunction across genomic, epigenetic, mitochondrial, proteostatic, and communicative processes. A large body of evidence supports that NAD⁺ can counter functional decline in models of neurodegenerative diseases, cardiometabolic diseases, and musculoskeletal aging However, a critical synthesis of evidence reveals a paradoxical, context-dependent role for NAD⁺, particularly in oncology, where it can sustain the pro-tumorigenic senescence-associated secretory phenotype (SASP) and fuel established cancers. This duality, along with tissue-specific metabolic nuances, underscores the fundamental limitation of indiscriminate "blind supplementation." Consequently, we advocate for a necessary paradigm shift towards "precision NAD⁺ modulation." Building on the integrated mechanistic analysis, we critically examine the therapeutic implications and challenges across major age-related diseases. Looking ahead, we propose that advancing the field requires embracing a "NAD⁺ systems biology" perspective. Design next-generation interventions that precisely balance tissue-specific NAD⁺ synthesis and consumption. This paradigm is essential for translating the promise of NAD⁺ biology into safe and effective strategies for extending human healthspan.
    Keywords:  Aging hallmarks; Healthspan; Metabolic regulation; NAD⁺; Precision geroscience; Sirtuins
    DOI:  https://doi.org/10.1016/j.mad.2026.112174
  31. Mikrochim Acta. 2026 Mar 12. pii: 236. [Epub ahead of print]193(4):
      
    Keywords:  Carbon dots; Mitochondrial morphology dynamic tracking; Mitochondrial targeting; Specific fluorescence response to Fe3+ ; Stable fluorescence performance
    DOI:  https://doi.org/10.1007/s00604-026-07927-6
  32. J Clin Invest. 2026 Mar 10. pii: e196094. [Epub ahead of print]
      Huntington's disease (HD) is a fatal neurodegenerative disorder characterized by progressive motor dysfunction, cognitive decline, and striatal neuron degeneration, primarily affecting medium spiny neurons (MSNs). Despite extensive research, the underlying metabolic vulnerabilities contributing to HD pathogenesis remain poorly understood. In this study, we employ RNA sequencing (RNA-seq) and metabolomics analyses to identify marked dysregulation of one-carbon metabolism in HD. We validate that SHMT2, a key mitochondrial enzyme in the mitochondrial one-carbon (mt-1C) pathway, is substantially downregulated in HD patient-derived iPSC-differentiated human striatal organoids (hSOs) and YAC128 mice. Functionally, pharmacological inhibition or genetic deletion of SHMT2 exacerbates mutant huntingtin (mHTT) aggregation, induces MSN degeneration in hSOs, and impairs motor function in WT mice. Conversely, SHMT2 overexpression attenuates MSN degeneration in HD-hSOs and improves motor performance in YAC128 mice. Mechanistically, SHMT2 deficiency leads to homocysteine (HCY) accumulation, which interacts with AARS1 and suppresses histone lactylation, thereby perturbing transcriptional regulation and associating with neurodegenerative phenotypes. Finally, we demonstrate that the HD clinical drug haloperidol modulates SHMT2 expression and restores histone lactylation, providing a pharmacological tool to probe SHMT2-dependent metabolic and epigenetic regulation in HD models. These findings highlight a metabolic-epigenetic axis as a promising therapeutic target for HD.
    Keywords:  Aging; Cell biology; Neurodegeneration; Neuroscience
    DOI:  https://doi.org/10.1172/JCI196094
  33. bioRxiv. 2026 Feb 28. pii: 2026.02.26.708335. [Epub ahead of print]
      Aging is accompanied by conserved hallmarks including genomic instability, epigenetic alterations, loss of proteostasis, and mitochondrial dysfunction, but how these processes emerge and become mechanistically linked remains unclear. Here we leverage a proteome-wide, single-cell, subcellular atlas of protein expression, localization, and aggregation across yeast replicative aging to map hallmark-linked remodeling in its spatial context. We identify hundreds of previously unappreciated molecular changes that underlie major hallmarks of aging and show that hallmark phenotypes frequently manifest as compartment-specific erosion of spatial confinement, relocalization, and aggregation. 91.6% human orthologs of these hallmark-linked yeast proteins also change during human aging. Integrating these spatial phenotypes reveals many molecular connections linking different hallmarks. Temporal analysis suggests that disorganization of nucleolar ribosome biogenesis, proteostasis decline, and mitochondrial dysfunction precede other hallmarks. Together, our findings substantially deepen the molecular underpinnings of aging hallmarks and provide a framework for linking them into a hierarchical sequence of cellular failures.
    DOI:  https://doi.org/10.64898/2026.02.26.708335
  34. BMB Rep. 2026 Mar 09. pii: 6743. [Epub ahead of print]
      Cellular senescence is an irreversible program of cell-cycle arrest that accumulates with age, contributing to chronic inflammation and various age-related diseases. A key feature of senescence paradigms is mitochondrial dysfunction, which involves not just a single defect but a series of coordinated changes in bioenergetics, redox homeostasis, mitochondrial quality control, and organelle interaction. Senescent cells often display a "quantity-quality imbalance" in their mitochondria: while the mitochondrial mass may increase, their efficiency in oxidative phosphorylation decreases, leading to a destabilized membrane potential (ΔΨm) and elevated levels of mitochondrial reactive oxygen species (mtROS). These interrelated changes can exacerbate senescence through persistent stress signaling, impaired turnover of damaged mitochondrial components, and alterations in organelle contacts, such as those between endoplasmic reticulum (ER) and mitochondria, and between mitochondria and lysosomes. Given that these phenotypes differ depending on cell type, triggering factors, and timing, no single assay can adequately define senescence-associated mitochondrial dysfunction. In this review, we present practical, complementary strategies that include extracellular flux-based respiration profiling, ATP output measurement, ΔΨm and ROS assessments, flux-based mitophagy reporters, quantitative network imaging, and contact-site assays. We propose minimal assay bundles that allow for a thorough multidimensional analysis. By establishing standardized, orthogonal measures of mitochondrial quantity and quality, we aim to enhance mechanistic understanding and facilitate the rational evaluation of mitochondria-targeted senolytic and senomorphic therapies.
  35. Int J Biol Sci. 2026 ;22(5): 2720-2735
       Background: Mitochondrial dysfunction is widely regarded as a central and early feature of Alzheimer's disease (AD) pathology. Prior studies suggest that the accumulation of amyloid precursor protein (APP) within mitochondria contributes to this dysfunction. Mutations in presenilin-1 (PS1), which account for most cases of early-onset familial AD (FAD), have also been shown to impair mitochondrial function. In this study, we investigated how APP influences PS1 mutation-induced mitochondrial dysfunction in human cortical neurons derived from patient induced pluripotent stem cells (iPSCs).
    Methods: We analyzed transcriptomic and proteomic datasets from postmortem sporadic AD cortex to identify key dysregulated pathways. To functionally interrogate selected mechanisms, we established a panel of CRISPR/Cas9-engineered human iPSC lines, including PS1 mutant lines (PS1+/F105C and PS1+/A246E), an APP knockout derivative (APP-/-_PS1+/F105C), and their isogenic wild-type controls. These iPSCs were differentiated into cortical neurons for functional studies. Following directed differentiation into cortical neurons, biochemical analyses and super-resolution imaging were conducted to evaluate mitochondrial and neuronal phenotypes.
    Results: Analyses of sporadic AD cortical transcriptomes and proteomes identified mitochondrial dysfunction as a prominently altered pathway. In agreement, cortical neurons differentiated from FAD PS1 mutant (F105C and A246E) iPSCs displayed mitochondrial defects and AD-related phenotypes, both of which were mitigated by APP knockout.
    Conclusions: These findings provide critical insights into the bridging role of APP in FAD PS1 mutant-mediated mitochondrial dysfunction, advancing our understanding of the cellular mechanisms underlying AD.
    Keywords:  Alzheimer's disease; CRISPR; amyloid precursor protein; iPSCs; mitochondrial dysfunction; presenilin 1
    DOI:  https://doi.org/10.7150/ijbs.120062
  36. BMC Psychiatry. 2026 Mar 10.
      
    Keywords:  Case report; Neuropsychiatry; Obsessive-compulsive; Psychopharmacology; Schizophrenia; TK2-related mitochondrial DNA depletion myopathy
    DOI:  https://doi.org/10.1186/s12888-026-07905-5
  37. Int J Mol Sci. 2026 Feb 27. pii: 2232. [Epub ahead of print]27(5):
      Mitochondria are a key organelle in maintaining metabolic homeostasis. It not only generates most of the cell's energy through oxidative phosphorylation but also acts as a complex sensor of the redox state and oxygen in the cell. This review thoroughly analyzes the interactions among mitochondrial iron metabolism, mitochondrial reactive oxygen species (mtROS), and lipid peroxidation (LPO), the triggering factors of ferroptosis, an iron-dependent form of programmed cell death. We point out research showing that intrinsic mitochondrial machinery, such as iron-sulfur (Fe-S) cluster assembly and heme metabolism, is both an important cofactor and a master regulator. If these processes are disrupted, they can lead to ferroptosis. Unlike views that focus on the cytosol, we explain that the stability of Fe-S clusters in complexes such as aconitase and respiratory Complex I is crucial for preventing electron leakage and excessive mtROS formation. The Fenton reaction and its direct effect on cardiolipin (CL) oxidation in the inner membrane of mitochondria is a central event in cardiometabolic diseases. Its peroxidation and breakdown make the organelle very unstable and lead to cell death though Ca2+ overload and a significantly decreased reduced/oxidized glutathione ratio. Additionally, the functions of essential iron transporters and glutathione homeostasis are examined, and their dysregulation is correlated with ferroptosis-associated progression of cardiometabolic and neurodegenerative disorders, such as obesity and Alzheimer's disease. This review focused on the need to revisit the classic bioenergetic core of the mitochondria as a key player in the pathophysiology of metabolic and neurodegenerative diseases.
    Keywords:  cardiolipin; complex I; ferroptosis; mitochondrial dysfunction
    DOI:  https://doi.org/10.3390/ijms27052232
  38. Int J Biol Sci. 2026 ;22(5): 2435-2451
      DNA polymerase gamma (Polγ), the sole polymerase for mitochondrial DNA (mtDNA), emerges as a critical regulator of metabolism-associated senescence. While lysine acetylation represents a key post-translational modification (PTM) influencing mitochondrial function, its mechanistic role in Polγ-mediated vascular aging remains undefined. Through combinatorial approaches employing in vitro acetylation models and POLG D257A/D257A mice, a validated model of mitochondrial dysfunction and senescence, we identify Lys 1039 (K1039) as a novel acetylation site which was dynamically regulated during aging process. Both D257A mutation-driven hyper-acetylation of Polγ K1039 reduced human aortic smooth muscle cell (HASMC) contractility, triggering pathological hyperproliferation and mitochondrial dysfunction, collectively culminating in premature cellular senescence. Pathological stimulation or genetic manipulation inducing hyperacetylation at K1039 disrupts Polγ's binding capacity with mtDNA. This molecular deficiency manifested functionally as compromised contractile performance in HASMCs and accelerated senescence phenotypes. Based on the above foundation and POLG D257A/D257A mice model, we demonstrated that D257A mutation reduced Sirt3-Polγ complex formation constituted the pathologically relevant molecular pathway driving aberrant acetylation homeostasis and leading to the senescence. Our findings establish a previously unrecognized regulatory axis wherein Polγ acetylation status at K1039 serves as a molecular switch coordinating mtDNA homeostasis, HASMCs functionality, and senescence progression. This mechanism might explain the remarkably consistent phenotypic manifestations of Polγ-induced dysfunction across diverse tissues and aging models. This work provides fundamental insights into the epigenetic-metabolic crosstalk governing vascular aging processes, providing a unifying framework for age-related vascular pathologies.
    Keywords:  Acetylation; DNA polymerase gamma; human aortic smooth muscle cells; mitochondrial homeostasis; senescence
    DOI:  https://doi.org/10.7150/ijbs.122298
  39. CNS Neurosci Ther. 2026 Mar;32(3): e70822
       AIMS: Parkinson's disease (PD) lacks effective disease-modifying therapies, despite mitochondrial dysfunction being a key pathogenic factor. This study aimed to identify novel regulators of mitochondrial dynamics and explore their therapeutic relevance.
    METHODS: Transcriptomic analysis was conducted on the substantia nigra (SN) of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD mice. SN-specific lentiviral knockdown or overexpression of nucleoside diphosphate kinase 3 (NME3) was performed in mice. Motor behavior, dopaminergic neuron survival, mitochondrial ultrastructure, and reactive oxygen species (ROS) levels were assessed. Mitochondrial fission was pharmacologically inhibited using the Drp1 inhibitor Mdivi-1.
    RESULTS: RNA sequencing revealed a marked reduction of Nme3 in the SN of MPTP-treated mice. Nme3 knockdown in healthy mice induced PD-like motor deficits and dopaminergic neurodegeneration, mimicking the MPTP model. Mechanistically, NME3 deficiency disrupted mitochondrial fission-fusion balance, causing abnormal mitochondrial morphology, excessive ROS production, and neuronal injury. Mdivi-1 treatment significantly alleviated mitochondrial dysfunction and neurotoxicity. Conversely, SN-specific Nme3 overexpression in MPTP-treated mice improved motor performance and preserved dopaminergic neurons by suppressing pathological mitochondrial fission.
    CONCLUSION: NME3 is a previously unrecognized regulator of mitochondrial dynamics and a critical contributor to PD pathogenesis. Restoring mitochondrial fission-fusion balance through genetic or pharmacological approaches provides neuroprotection, highlighting NME3 as a promising target for disease-modifying PD therapies.
    Keywords:  NME3; Parkinson's disease; disease‐modifying intervention; mitochondrial dynamics; neuroprotection
    DOI:  https://doi.org/10.1002/cns.70822
  40. medRxiv. 2026 Mar 03. pii: 2026.02.27.26347078. [Epub ahead of print]
      Developmental and epileptic encephalopathies (DEEs) are a group of severe childhood-onset neurological disorders, often caused by rare genetic variants affecting brain development and excitability. Despite advances in genomic sequencing, a substantial proportion of DEE cases remain unsolved. Here, we identify THAP12 as a novel disease-causing gene associated with autosomal recessive DEE. Whole-genome sequencing in two siblings who presented with infantile spasms and progressed to Lennox-Gastaut syndrome revealed compound heterozygous variants in THAP12 , leading to a reduction in protein abundance, consistent with a loss-of-function mechanism. To confirm this mechanism in vivo , we generated mouse models carrying either of the two patient-specific alleles. Both homozygous and compound heterozygous animals exhibited embryonic lethality, confirming the essential and dosage-sensitive role of Thap12 during early development. Zebrafish loss-of-function models recapitulated major aspects of the human phenotype, including microcephaly, brain hypoplasia, abnormal neuronal activity, and increased seizure sensitivity. Transcriptomic profiling of larval zebrafish brains revealed dysregulation of cell cycle and apoptotic pathways, in line with increased cell death and reduced proliferation observed in mutant embryos. Notably, overexpression of wild-type human THAP12 mRNA rescued these in vivo phenotypes, while the patient-derived variants allele failed to do so. Altogether, our findings demonstrate that THAP12 is essential for early brain development and neuronal survival, and that biallelic loss-of-function variants in this gene underlie a previously unrecognized etiology of autosomal recessive DEE. These results provide a mechanistic framework linking, for the first time, THAP12 dysfunction to neurodevelopmental pathology and open new avenues for diagnosis in undiagnosed DEE cases.
    DOI:  https://doi.org/10.64898/2026.02.27.26347078
  41. ArXiv. 2026 Mar 05. pii: arXiv:2511.02263v4. [Epub ahead of print]
      Rare disease diagnosis requires matching variant-bearing genes to complex patient phenotypes across large and heterogeneous evidence sources. This process remains time-intensive in current clinical interpretation pipelines. To overcome these limitations, We present LA-MARRVEL, a knowledge-grounded, language-aware LLM framework and designed for clinical robustness and practical deployment. LA-MARRVEL delivers a 12-15 percentage-point absolute improvement in Recall@1 over established gene prioritization approaches, showing that architectural design can drive substantial accuracy gains. We found that the central contributor is structured, phenotype-rich prompt construction that explicitly encodes patient and disease phenotypes, preserving clinically meaningful context more effectively than disease labels alone. Across three real-world cohorts, LA-MARRVEL consistently improves gene-ranking performance, including in challenging cases where the causal gene was initially ranked lower by first-stage prioritization. For each candidate gene, the system delivers clinically relevant, ACMG-aligned reasoning that integrates phenotype concordance, inheritance patterns, and variant-level evidence into auditable explanations, enabling streamlined clinical review. These findings suggest that knowledge-grounded LLM layer can enhance existing rare-disease gene prioritization workflows without altering established diagnostic pipelines.
  42. Proc Natl Acad Sci U S A. 2026 Mar 17. 123(11): e2534452123
      Phenotypic heterogeneity is prevalent during aging, yet its underlying molecular drivers remain poorly understood. In budding yeast, two distinct aging trajectories, characterized by either ribosomal DNA (rDNA) instability or mitochondrial decline, have been proposed to be mutually exclusive. Here, we systematically dissect the heterogeneity among aging yeast cells by combining single-cell transcriptomics with longitudinal fluorescence microscopy. Our data reveal distinct transcriptional responses that emerge in aging cells, highlighted by loss of rDNA silencing, a hypoxia response, and the environmental stress response (ESR). Contrary to expectation, we establish that ESR induction is not caused by rDNA instability but is instead a consequence of an early decline in mitochondrial membrane potential. However, the ESR is merely a biomarker of this decline and not itself a determinant of lifespan. While rDNA instability and mitochondrial dysfunction are anticorrelated as terminal phenotypes, we find that they are not necessarily mutually exclusive and can instead proceed concurrently within individual cells. Targeted genetic perturbations that are specific for one pathway do not impinge on the other, which is in contradiction to the idea of mutual inhibition between the two. We therefore propose a "competing hazards model", where independent aging processes progress in parallel, and the observed mode of death is determined by which process first reaches a catastrophic failure point. Our work untangles the causal links between several aging pathways and provides a framework for understanding how distinct aging trajectories emerge from independent molecular events.
    Keywords:  aging; mitochondria; phenotypic heterogeneity; single-cell RNA seq; yeast
    DOI:  https://doi.org/10.1073/pnas.2534452123
  43. Structure. 2026 Mar 11. pii: S0969-2126(26)00051-1. [Epub ahead of print]
      Mitochondrial ribosome biogenesis depends on RNA helicases such as DDX28, a DEAD-box helicase that plays an essential role during early mitoribosome large-subunit assembly by interacting with 16S rRNA. Here, we demonstrate that the helicase core domain of DDX28 binds sequence and structure specifically to the H88_L stem-loop in 16S rRNA, with the RecA2 domain residue M431 as a key determinant for substrate selectivity. The N-terminal disordered region of DDX28 enhances nonspecific RNA binding but does not contribute to enzymatic activity. Furthermore, DDX28 deficiency disrupts mitochondrial translation, impairs OXPHOS complex assembly, and leads to metabolic dysfunction, including reduced membrane potential, elevated ROS, and suppressed glycolysis. Transcriptomic and metabolomic analyses reveal a compensatory upregulation of ribosome biogenesis genes alongside a dysregulation of the TCA cycle, oxidative phosphorylation, and lipid metabolism. Our integrated structural and functional study establishes DDX28 as an essential factor for mitoribosome assembly with potential links to mitochondrial disorders.
    Keywords:  DDX28; DEAD-box helicase; Mitabolic dysregulation; Mitochondrial dysfunction; RNA recognition
    DOI:  https://doi.org/10.1016/j.str.2026.02.009
  44. Int J Mol Sci. 2026 Feb 24. pii: 2117. [Epub ahead of print]27(5):
      Mitochondria-endoplasmic reticulum contacts (MERCs) are physical structures formed between mitochondria and the endoplasmic reticulum (ER) through various tethering proteins, playing crucial roles in multiple physiological processes, including Ca2+ and lipid exchange between the ER and mitochondria, regulation of mitochondrial morphology and dynamics (fusion and fission), as well as the induction of autophagy and apoptosis. Mitofusin 2 (MFN2), a key mitochondrial fusion protein, has been identified as an essential structural component of MERCs. Our research demonstrates that 16:8 circadian intermittent fasting (CIF) leads to enhanced mitochondrial fusion. The upregulation of MFN2 reinforces MERC stability, thereby facilitating efficient Ca2+ transfer between the ER and mitochondria. This process sustains the activity of mitochondrial oxidative phosphorylation (OXPHOS) enzymes, elevates mitochondrial oxygen utilization efficiency, and ultimately augments ATP production. Consequently, these adaptations enhance cardiomyocyte tolerance to hypoxic conditions. This study elucidates a novel mechanism by which MERCs regulate cellular hypoxia resistance and proposes a potential therapeutic strategy for improving acute hypoxia tolerance through the modulation of Ca2+ transport at MERCs.
    Keywords:  MERC; calcium transport; cardiomyocyte; circadian intermittent fasting; hypoxia; mitofusin 2
    DOI:  https://doi.org/10.3390/ijms27052117
  45. Free Radic Biol Med. 2026 Mar 11. pii: S0891-5849(26)00225-X. [Epub ahead of print]
      Mitochondrial stress (MS) is a hallmark of a number of aging-associated neurodegenerative diseases, including Parkinson's disease (PD). Chronic MS in PD disrupts neuronal proteostasis, causing dopaminergic neurodegeneration through inactivation of an E3 ubiquitin ligase, parkin, although the mechanism of its inactivation is not understood. Here, we elucidate a mechanistic framework linking progressive changes in mitochondrial mass with MS-induced alterations in parkin activity. We showed that acute and chronic MS differentially modulate parkin activity and regulate mitochondrial biogenesis by transcriptional control of peroxisome proliferator-activated receptor γ coactivator 1α (PGC1α), through parkin substrate PARIS (parkin-interacting substrate). Acute exposure to the PD neurotoxin, 1-methyl-4-phenylpyridinium (MPP+), activates the parkin-PARIS-PGC1α pathway, transiently facilitating mitochondrial biogenesis. However, sustained and repetitive MS leads to parkin mis localization, inactivation, and aggregation, resulting in PARIS accumulation, repression of PGC1α activity, and loss of mitochondrial mass. Nuclear Factor Erythroid 2-related Factor 2 (NFE2L2 or NRF2) activation by methylene blue (MB) transcriptionally upregulates parkin expression by enhancing its binding to NRF2/ antioxidant responsive element (ARE) within the PARK2 promoter. MB treatment in cells exposed to chronic MPP+ reduces PARIS levels, restores PGC1α activity, and rejuvenates mitochondria. These findings underscore the impact of chronic mitochondrial damage on parkin dysfunction in PD and suggest a promising role for MB in protecting against mitochondrial and proteostatic failure in PD by targeting the NRF2-parkin axis.
    Keywords:  E3 ubiquitin ligase; dopaminergic neurodegeneration; mitochondria; parkin; proteostasis
    DOI:  https://doi.org/10.1016/j.freeradbiomed.2026.03.034
  46. Circ Res. 2026 Mar 11.
       BACKGROUND: SCN5A encodes the cardiac NaV1.5 (voltage-gated Na+ channel), classically known for initiating action potentials and recently implicated in cardiomyocyte metabolism via mitochondrial Na+/Ca2+ exchange. SCN5A variants are linked to arrhythmias and heart failure, but mechanisms controlling SCN5A/NaV1.5 expression and its metabolic interface remain understudied.
    METHODS: We used bioinformatic approaches to identify novel SCN5A regulatory features and discovered an alternative polyadenylation (APA) signal downstream of exon 2, which is conserved in humans and several other species but not mice. To test its function, we generated knock-in mice harboring the human APA signal. Western blotting, cell fractionation, and fluorescence microscopy were used to characterize the resulting truncated protein isoform that localizes to mitochondria. Mitochondrial functions and metabolites were assessed in neonatal rat cardiomyocytes, human-induced pluripotent stem cell-derived cardiomyocytes, and mouse hearts overexpressing the novel isoform.
    RESULTS: We identified a well-conserved APA signal downstream of SCN5A exon 2, yielding a truncated transcript isoform (SCN5A-short). Reanalysis of cardiac APA-seq and mRNA-seq data reveals reduced SCN5A-short expression in failing human hearts. Knock-in of the human APA signal into mice enables expression of SCN5A-short while decreasing full-length SCN5A mRNA. SCN5A-short encodes a novel NaV1.5-NT (N-terminal fragment of NaV1.5) that localizes to the mitochondrial matrix in cardiomyocytes and mouse hearts. Exogenous expression of NaV1.5-NT in cultured cardiomyocytes enhances mitochondrial respiration, ATP production, and mitochondrial ROS while depleting NADH. Native polyacrylamide gel electrophoresis analyses indicate that this coincides with enhanced CI (complex I) activities, as well as context-dependent alterations of CV (complex V) assembly. Moreover, moderate cardiomyocyte-targeted NaV1.5-NT expression in mice was sufficient to rewire the cardiac metabolome, with suggestive evidence of increased fatty acid oxidation.
    CONCLUSIONS: APA-mediated regulation of SCN5A produces a short transcript encoding NaV1.5-NT, a novel mitochondrial-targeted peptide that supports cardiomyocyte metabolism. While the precise molecular mechanisms remain unresolved, these findings highlight an unforeseen alternative pathway for expanding SCN5A-mitochondrial crosstalk, with potential implications for metabolic changes in heart failure and arrhythmias.
    Keywords:  action potentials; cardiomyopathy, dilated; defibrillators, implantable; mitochondria; sodium channels
    DOI:  https://doi.org/10.1161/CIRCRESAHA.125.326973
  47. bioRxiv. 2026 Feb 23. pii: 2026.02.23.707539. [Epub ahead of print]
      The force-generating AAA+ ATPase domain of protein unfoldases is specified for many substrates and other functional partners through elaboration with accessory domains. Mitochondrial homologs of the unfoldase ClpX contain an insertion within the AAA+ domain that is absent in bacterial homologs. This mitochondrial insertion (MI) maps to the substrate-encountering face of ClpX, leading us to hypothesize that the MI directs interactions of ClpX with mitochondrial substrates, the best-characterized of which is the first enzyme in heme biosynthesis, ALAS. We find that the MI is critical for both recruitment and activation of ALAS by S. cerevisiae ClpX. The MI was dispensable for heme-induced, adaptor-mediated degradation of ALAS by human CLPXP, but contributed to adaptor-independent recruitment of the model substrate casein for degradation. Although truncation of the MI moderately perturbed ATPase activity in both yeast and human ClpX, this effect could be uncoupled from the requirement for the MI in the efficiency of ALAS activation by targeted mutagenesis. The MI therefore can serve both to recruit a substrate to mitochondrial ClpX and to accelerate its processing by the AAA+ motor.
    DOI:  https://doi.org/10.64898/2026.02.23.707539
  48. Cell Death Differ. 2026 Mar 13.
      Diabetic complications frequently arise in mechanically stressed regions, yet the molecular links between biomechanical forces and metabolic dysfunction remain unclear. Here, we demonstrate that mechanical stress induces glucose accumulation and downstream metabolic stress in keratinocytes. Mechanistically, Piezo1 activation led to intracellular glucose overload and advanced glycation end-products (AGEs) accumulation, which induced mitochondrial DNA (mtDNA) leakage into the cytosol and subsequently activated the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling cascade (cGAS-STING pathway). Keratinocyte-specific Piezo1 deletion markedly reduced AGEs accumulation and preserved mitochondrial integrity, and STING ablation exhibited similar downstream protective effects. Notably, we identify Cortistatin (CST), an endogenous neuropeptide, as a previously unrecognized inhibitory ligand of Piezo1. CST binding attenuates calcium influx and glucose accumulation under mechanical stress, conferring notable protection in vitro and in diabetic ulcers (DUs) models. These findings uncover a CST-Piezo1-STING regulatory axis that integrates mechanical and metabolic cues to drive keratinocyte dysfunction in diabetes.
    DOI:  https://doi.org/10.1038/s41418-026-01699-5
  49. FASEB J. 2026 Mar 31. 40(6): e71674
      Barth Syndrome (BTHS) is a debilitating X-linked genetic disorder caused by mutations in the gene encoding TAFAZZIN, an enzyme responsible for the remodeling of cardiolipin. While cyclic neutropenia is a well-recognized immunological feature of this disease, emerging evidence suggests that lymphopenia may also occur. The objective of this study was to examine the effects of cannabidiol (CBD) on growth, cardiolipin content, and mitochondrial abnormalities in BTHS patient-derived B-lymphoblastoid cells. CBD (1 μM) restored the growth of BTHS B-lymphoblastoids to healthy control levels, but did not alter cell cycle distribution or sub-G1 cell populations, which surprisingly also did not differ from healthy control B-lymphoblastoids. CBD treatment also fully restored the total cellular cardiolipin concentration and reversed the elevation in monolysocardiolipin/cardiolipin ratio in BTHS B-lymphoblastoids to healthy cell levels, but did not restore the cardiolipin fatty acyl composition. Assessment of mitochondrial markers suggested that increased cardiolipin did not result from increased mitochondrial content. This improvement in cardiolipin concentration was associated with a significant increase in the maximal coupled state III respiration of BTHS B-lymphoblastoids, with all five tested BTHS donors exhibiting increased mitochondrial membrane potential following CBD treatment. CBD fully reversed the deficit in succinate dehydrogenase subunit A in BTHS cells, and partially reversed deficits in cytochrome c oxidase subunits I and IV, and partially restored supercomplex I/III2 levels, but did not rescue I/III2/IV levels. This work suggested a potential role for CBD as a therapeutic in BTHS B-lymphopenia that merits further investigation.
    Keywords:  Barth syndrome; B‐lymphoblastoid cells; Cannabidiol; Cardiolipin; TAFAZZIN; electron transport chain; mitochondria
    DOI:  https://doi.org/10.1096/fj.202503384R
  50. Front Cell Dev Biol. 2026 ;14 1784579
      Beige adipocytes have emerged as an attractive therapeutic target for metabolic disease due to their inducible thermogenic capacity and developmental plasticity. However, despite substantial advances in understanding the molecular pathways that activate thermogenesis, most thermogenic strategies have shown limited durability in pathological settings. This article integrates recent discoveries in adipocyte cell biology to argue that thermogenic failure reflects a loss of cellular competence rather than insufficient stimulation. We review emerging evidence demonstrating that mitochondrial capacity, intracellular signaling fidelity, and vesicle trafficking impose critical cell-intrinsic constraints on beige adipocyte function, particularly in obesity and aging. These insights highlight why chronic, systemic activation strategies often fail to produce sustained metabolic benefits. Drawing on principles from developmental biology, we propose that restoring thermogenic function will require precision control of adipocyte cell state, including spatially and temporally defined modulation of signaling pathways. Emerging technologies enabling reversible, cell-targeted control of adipocyte function, coupled with human cell-based models, offer new opportunities to overcome current limitations. Together, this perspective emphasizes that beige adipocytes are not merely thermogenic effectors, but dynamic cellular systems whose therapeutic potential depends on maintaining or restoring adaptive plasticity.
    Keywords:  aging; beige adipocytes; cellular competence; mitochondrial quality control; obesity; thermogenesis
    DOI:  https://doi.org/10.3389/fcell.2026.1784579
  51. J Biol Inorg Chem. 2026 Mar 09.
      
    Keywords:  Hydrogen sulfide; Hypoxia; Iron-sulfur cluster; Mitochondria; Nitric oxide; mitoNEET
    DOI:  https://doi.org/10.1007/s00775-026-02139-y
  52. Neuron. 2026 Mar 11. pii: S0896-6273(26)00086-3. [Epub ahead of print]
      Amyotrophic lateral sclerosis (ALS) is genetically and clinically heterogeneous, yet convergent pathogenic mechanisms remain poorly defined. A CRISPR-Cas9 screen identified phosphoglycerate mutase-5 (PGAM5) as a common mediator of ALS pathogenesis. PGAM5 activates the mitochondrial integrated stress response (mtISR) via dephosphorylation of metallopeptidase OMA1 at Ser223 and Ser237, thereby driving neuromuscular junction disruption and motor deficits. We show that PGAM5 is a substrate of valosin-containing protein (VCP) and is consistently elevated in spinal cords from sporadic ALS patients, in human spinal cord organoids derived from sporadic or familial ALS, and in ALS mouse models. The disruption of PGAM5-OMA1 interaction by a selective inhibitor (TAT-PO1) or pharmacological inhibition of PGAM5 with telmisartan suppresses mtISR activation and ameliorates ALS-related phenotypes by reshaping mtISR outputs in a manner distinct from those elicited by activation of translation initiation factor 2B (eIF2B). These findings establish PGAM5 as a convergent and actionable therapeutic target across ALS subtypes.
    Keywords:  ALS; NMJ; PGAM5; VCP; amyotrophic lateral sclerosis; mitochondrial integrated stress response; mitochondrial phosphatase phosphoglycerate mutase 5; mtISR; neuromuscular junction; valosin-containing protein
    DOI:  https://doi.org/10.1016/j.neuron.2026.02.003
  53. J Transl Med. 2026 Mar 07. pii: 331. [Epub ahead of print]24(1):
      
    Keywords:  Glaucoma; Mitochondria transplantation; Mitophagy; OHT; POAG; Trabecular meshwork
    DOI:  https://doi.org/10.1186/s12967-026-07964-y
  54. Nature. 2026 Mar 10.
      
    Keywords:  Cell biology; Computational biology and bioinformatics
    DOI:  https://doi.org/10.1038/d41586-026-00786-4
  55. Transl Pediatr. 2026 Feb 28. 15(2): 43
       Background: Up to 40% of neonatal seizures remain unexplained after standard evaluation, creating a diagnostic imperative. Distinguishing genetic etiologies is critical, as it enables the identification of treatable conditions and informs prognosis and family counseling. In this study, we aimed to define the genetic spectrum of unexplained neonatal seizures in a Chinese cohort.
    Methods: In this single-center retrospective case series, we enrolled 40 neonates [2016-2024] admitted to the neonatal intensive care unit with video electroencephalography (vEEG)-confirmed seizures that were "unexplained" after a comprehensive evaluation including neuroimaging and metabolic screening. Exclusion criteria included identified causes such as hypoxic-ischemic encephalopathy or confirmed metabolic disorders. Genetic analysis involved whole-exome sequencing (WES), clinical exome sequencing (CES), WES of patient and parents (trio) (trio-WES), and mitochondrial DNA analysis.
    Results: The cohort included 29 male and 11 female neonates, with a median seizure onset at 1.5 days of life. Pathogenic or likely pathogenic variants were detected in 67.5% (27/40) of cases, including, but not limited to, variants in KCNQ2, ALDH7A1, and SUOX. A dual diagnosis was identified in one individual with compound heterozygous SUOX mutations and a de novo TUBG1 deletion. Additionally, nine of the 28 identified variants were novel. Although diagnostic yields varied among methodologies, the differences were not significant. Three patients with ALDH7A1 mutations achieved seizure freedom with vitamin B6 alone. All patients with SUOX nonsense/frameshift mutations had severe phenotypes and poor outcomes.
    Conclusions: Our findings demonstrate a high diagnostic yield of next-generation sequencing (NGS) in unexplained neonatal seizures and underscore its clinical utility in pinpointing treatable conditions and prognosticating severe disorders.
    Keywords:  Epilepsy; neonatal seizures; next-generation sequencing (NGS); variant; whole-exome sequencing (WES)
    DOI:  https://doi.org/10.21037/tp-2025-aw-750
  56. Nat Commun. 2026 Mar 13.
      Dietary fat absorption is among the most energy-demanding processes of nutrient uptake. Fatty acid activation, triglyceride synthesis, and the trafficking of chylomicrons through the secretory pathway - all require ATP. How enterocytes accommodate the surge in ATP consumption following fat uptake is unclear. We show that the purine biosynthesis/salvage pathway supplies necessary ATP and that Ankyrin Repeat Domain 9 (ANKRD9) couples ATP synthesis and lipoprotein trafficking. Ankrd9 regulates enzymes within the purine biosynthesis pathway to increase ATP synthesis and facilitate Golgi dynamics. Intracellular localization of ANKRD9 is lipid and ATP-dependent. Inactivation of Ankrd9 in mice reduces intestinal ATP despite intact mitochondrial and glycolytic function, alters Golgi morphology, delays ApoB/chylomicron trafficking, and causes lipid accumulation in enterocytes, along with a lean body phenotype. Taken together, the results reveal a previously unrecognized mechanism that regulates lipid absorption in enterocytes and identify ANKRD9 as a central component of this mechanism.
    DOI:  https://doi.org/10.1038/s41467-026-70332-3
  57. Arch Biochem Biophys. 2026 Mar 11. pii: S0003-9861(26)00061-5. [Epub ahead of print] 110790
      Studies have revealed an association between elevated neuronal cholesterol and neuronal dysfunction, in particular, mitochondrial impairment. However, the mechanism by which cholesterol disrupts neuronal mitochondrial function remains unclear, which prompts our current investigation. Using cultured HT22 mouse hippocampal neuronal cells as an in-vitro model, we found that the unmetabolized cholesterol, rather than its ester derivatives, can alter the MTT activity in cultured neuronal cells in a concentration-dependent manner, with an apparent IC50 ≤1 μM. At low micromolar concentrations (≤10 μM), cholesterol selectively disrupts mitochondrial function without causing overt cell death or reducing cell density. Functional and structural analyses revealed increased mitochondrial lipid peroxidation, loss of mitochondrial membrane potential, opening of the mitochondrial permeability transition pore, disruption of mitochondrial membrane integrity and ultrastructure, reduced mitochondrial density, and decreased cellular ATP levels. Seahorse-based bioenergetic profiling further demonstrated marked reductions in basal respiration, maximal respiratory capacity, and ATP-linked respiration, indicating a broad impairment of mitochondrial oxidative metabolism. In contrast, higher cholesterol concentrations (100 μM) induced overt cytotoxicity. Furthermore, genes involved in cholesterol biosynthesis (e.g., HMGCR, HMGCS1) and transport (e.g., STARD4, ABCA1), as well as mitochondrial energy metabolism pathways, are altered in cholesterol-treated neuronal cells. These results suggest that free cholesterol at very low concentrations can induce selective mitochondrial toxicity in cultured neurons and impairs mitochondrial ATP production. These findings shed lights on the crucial role of dysregulated cholesterol homeostasis in the pathogenesis of neurodegenerative diseases and also form the basis for therapeutic interventions.
    Keywords:  ATP Synthesis; Cholesterol; Cholesterol Biosynthesis; Mitochondrial Dysfunction; Mitochondrial Impairment
    DOI:  https://doi.org/10.1016/j.abb.2026.110790
  58. J Biol Chem. 2026 Mar 09. pii: S0021-9258(26)00230-9. [Epub ahead of print] 111360
      The base excision repair (BER) pathway maintains genomic integrity in the face of oxidative insult. It is initiated by DNA glycosylases such as 8-oxoguanine DNA glycosylase (OGG1) and is implicated in various pathologies such as cancers and neurodegenerative disease. BER proteins also modulate body weight and metabolic health. Mice lacking OGG1 are susceptible to obesity and its sequelae, while overexpression of human OGG1 (in OGG1-transgenic; Ogg1Tg mice) reverses these metabolic defects. We report here that OGG1 overexpression induces a remarkable over 3-fold increase in muscle endurance. This is accompanied by significant increases in muscle mitochondrial content and size and a selective increase in expression of the myokine, Fgf21, in skeletal muscle of Ogg1Tg mice. Together with elevated circulating FGF21 levels and peripheral markers of FGF21 action, these data demonstrate a novel role for skeletal muscle OGG1 in modulating mitochondrial health and muscle endurance via FGF21 secretion and signaling.
    Keywords:  base excision repair; exercise tolerance; fibroblast growth factor; mitochondria; myokine; skeletal muscle
    DOI:  https://doi.org/10.1016/j.jbc.2026.111360
  59. J Exp Med. 2026 Apr 06. pii: e20250978. [Epub ahead of print]223(4):
      Macrophage antibacterial activity requires mtROS production. The specific gene(s) that participates in the mtROS-mediated antibacterial process remains unclear. We showed that Listeria and Salmonella infections in human and mouse macrophages increased mtDNA copy number with which dictates antibacterial activity. Interestingly, adenylate kinase 4 (Ak4) expression was upregulated in macrophages after infection. Ak4 KO mice as well as macrophage-specific Ak4 KO mice became highly susceptible to bacterial infections. Ak4 is critical for the increase of mtDNA synthesis and mitochondrial mass in macrophages after bacterial infection. Biochemically, Ak4 transfers a phosphate group from ATP/GTP to (d)AMP for (d)ADP formation, and the K18A and G89S/A166D mutations abolished this function. Our results suggest that induction of Ak4 after infection produces more dADP, whose conversion to dATP in mitochondria supports mtDNA synthesis and the subsequent increase of mtROS production. Loss of this metabolic coupling in Ak4 KO macrophages diminishes antibacterial activity. Our findings highlight the vital role of Ak4 in macrophage defense against pathogenic bacteria.
    DOI:  https://doi.org/10.1084/jem.20250978
  60. Mol Ther. 2026 Mar 09. pii: S1525-0016(26)00113-9. [Epub ahead of print]
      Insufficient energy supply due to impaired mitochondria has emerged as a key pathological factor in the development of heart failure (HF) after myocardial infarction (MI). Unfortunately, no current therapeutic strategies directly augment myocardial energy production. While mitochondrial biogenesis is orchestrated by the activity of multiple genes, activation of PPARGC1A, a key regulator, can increase cellular mitochondria; however, supraphysiological levels of PPARGC1A result in adverse tissue remodeling and heart dysfunction. CRISPR activation (CRISPRa) technologies present a unique opportunity to address these shortcomings, as they enable tunable control over endogenous target gene expression. Here, we demonstrate that transcriptional activation of PPARGC1A using CRISPRa increases cellular mitochondria in human cell types. This effect is mediated through the activation of transcriptional programs driving mitochondrial biogenesis, mitochondrial function, and cellular bioenergetics. These activated transcriptional programs synergize to increase ATP production and reserve capacity in human cardiomyocytes. CRISPRa targeting of PPARGC1A in vivo increases cardiac mitochondria to recover heart ejection fraction in an acute MI model. Furthermore, CRISPRa acts on the adult human heart to increase PPARGC1A protein and cellular mitochondria, elevating mitochondrial function in both normal and HF-diagnosed hearts. These results provide the first proof of concept that endogenous gene activation via CRISPRa can improve heart function after MI.
    Keywords:  CRISPRa; MI; PGC-1α; bioenergetics; cardiomyopathies; gene therapies; mitochondrial biogenesis; myocardial infarction
    DOI:  https://doi.org/10.1016/j.ymthe.2026.02.027
  61. Basic Res Cardiol. 2026 Mar 13.
      Myocardial ischemia/reperfusion (I/R) injury is exacerbated by inflammation, yet the upstream triggers of this cascade and their amenability to therapeutic intervention remain unclear. The cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway is a driver of sterile inflammation in I/R injury, but whether its activation can be suppressed via enhanced mitochondrial quality control has not been explored. We hypothesized that augmenting PARKIN-mediated mitophagy would limit cGAS-STING activation and attenuate I/R injury by clearing damaged mitochondria and preventing the release of its agonist, mitochondrial DNA (mtDNA). Cardiomyocyte-specific PARKIN overexpression in mice was well tolerated at baseline and conferred cardioprotection following I/R injury, attenuating adverse remodeling and preserving cardiac function. Mechanistically, PARKIN overexpression enhanced mitophagy, which limited cytosolic mtDNA accumulation, thereby inhibiting cGAS-STING activation and its downstream inflammatory response. The therapeutic potential of this pathway was further supported by lentiviral PARKIN delivery in wild-type mouse hearts, which also improved cardiac outcomes following I/R injury. Taken together, our findings delineate a PARKIN-mtDNA-cGAS-STING axis as a regulatory mechanism of I/R injury and support PARKIN augmentation as a potential therapeutic strategy.
    Keywords:  Inflammation; Mitophagy; Myocardial ischemia/reperfusion injury; PARKIN; cGAS–STING activation; mtDNA
    DOI:  https://doi.org/10.1007/s00395-026-01169-6
  62. Arch Physiol Biochem. 2026 Mar 13. 1-22
      Critical limb ischaemia (CLI), a severe peripheral artery disease, reduces blood flow, disrupting lipid metabolism and mitochondrial function. This leads to muscle loss, impaired repair, and greater limb loss risk. Standard diagnostics emphasise imaging and perfusion, often missing metabolic changes. The LIPID-CLI framework uses high-resolution mass spectrometry to analyse lipid shifts under mitochondrial stress. Biopsy limits shifted focus to blood markers reflecting tissue lipids. Altered ceramides and phospholipids indicate lipid-mitochondrial dysfunction and may serve as non-invasive biomarkers for early CLI detection and treatment. The method improves ceramides (400 mL), phospholipid ratio (1.5), acylcarnitines (6 L), OxPLs (300 mL), index score (<0.4), and mediator levels (200 mL). The reduction denotes decreased ceramide concentration (µmol/mL or ng/mL), normalised to total lipid content in affected tissues. This measure reflects how ceramide alterations disrupt lipid homeostasis and mitochondrial function in critical limb ischaemia (CLI).
    Keywords:  Lipidomics; arteriosclerosis obliterans; biomarkers; critical limb ischaemia; mass spectrometry; mitochondrial dysfunction
    DOI:  https://doi.org/10.1080/13813455.2025.2592019
  63. Cell Rep Methods. 2026 Mar 12. pii: S2667-2375(26)00028-7. [Epub ahead of print] 101328
      DNA methylation is a key regulatory mechanism reflecting both short- and long-term biological stimuli. While it has been widely used to study aging through disease-associated methylation shifts, its potential for revealing tissue-specific shifts remains underexplored due to the lack of comprehensive reference atlases with correspondingly systematic analysis framework. To address this, we assemble the largest and most diverse atlas of healthy human tissue and cells profiled by 450K arrays, totaling 16,959 samples across 86 tissues and cell types. Using this resource, we introduce an ontology-aware classification framework that identifies robust CpG features linked to tissue and cell identity and incorporates known anatomical and functional relationships. Through minipatch learning, we distill 190 CpGs that support accurate multilabel classification and validate the approach with ontology-based label transfer to 31 unseen tissue and cell types.
    Keywords:  CP: genetics; CP: systems biology; CpG feature selection; DNA methylation; cell-type identification; epigenomics; machine learning; methylation biomarkers; multilabel classification; ontology; reference atlas; tissue classification
    DOI:  https://doi.org/10.1016/j.crmeth.2026.101328
  64. Epilepsia. 2026 Mar 08.
       OBJECTIVE: Genetic testing has become a routine part of clinical epilepsy care. Family history is an indication for genetic testing, but the diagnostic yield, predictors of a genetic diagnosis, and association with familial patterns are not well understood.
    METHODS: This was a retrospective cohort study of genetic testing performed at pediatric and adult epilepsy genetics clinics. Eligible patients (probands) had epilepsy and one or more first-degree relatives or two or more other relatives with epilepsy. Genetic testing strategies were patient specific, reflecting real-world clinical practice. Familial patterns were classified based on affected relatives of the proband. Diagnostic variants were tested in the proband's parents when possible.
    RESULTS: We studied 484 probands and their families. A genetic diagnosis was identified in 99 of 484 (20%). Predictors of a genetic diagnosis were presence of neurodevelopmental disorder (X2(1) = 9.6, p = .002) and earlier age at seizure onset (Mann-Whitney U test, p < .001). The likelihood of a genetic diagnosis was not associated with epilepsy type, drug resistance, brain magnetic resonance imaging (MRI) findings, number of affected first-degree relatives, total number of affected relatives, or having an affected parent with epilepsy. Among those with genetic diagnoses, variant segregation matched the familial pattern of affected individuals in 79%. The other 21% of families had unexpected segregation, including de novo variants in patients with affected ancestors and inherited variants in patients with no known affected ancestors.
    SIGNIFICANCE: Familial epilepsy has a substantial rate of genetic diagnosis and is an appropriate indication for genetic testing. Pedigree-related factors did not influence the likelihood of genetic diagnosis, suggesting that all families can be considered for genetic testing, independent of inheritance patterns and number of affected relatives. Familial patterns can help interpret genetic test results, while also revealing the complexities of incomplete penetrance and independent epilepsy etiologies in families.
    Keywords:  exome sequencing; familial epilepsy; family history; gene panel; genetic testing
    DOI:  https://doi.org/10.1002/epi.70160
  65. Free Radic Biol Med. 2026 Mar 09. pii: S0891-5849(26)00214-5. [Epub ahead of print]
      Growing nanoplastics exposure raises concern for neurotoxicity, particularly given recent evidence of plastic accumulation within human brain tissue a highly lipid enriched organ, yet effects on brain lipid metabolism remain poorly understood. Here, we employed high-resolution untargeted lipidomics to map brain lipid perturbations in Drosophila melanogaster chronically exposed to environmentally relevant levels of polystyrene nanoplastics (PS- NPs). PS-NPs accumulated in fly brains and induced dose-dependent remodeling of mitochondrial membrane lipids, notably cardiolipins and phosphatidylethanolamines, accompanied by increased diacylglycerols/triacylglycerols and monounsaturated fatty acids and by lipid droplet expansion. Guided by these lipidomic signatures, targeted biochemical assays demonstrated depolarized mitochondrial membrane potential, elevated mitochondrial reactive-oxygen species, inhibition of respiratory-chain complexes I and IV, and a shift in NAD(H) and NADP(H) redox couples toward a reduced state and increasing lipid peroxidation. This redox imbalance was accompanied by decreased tyrosine-hydroxylase expression, dopamine depletion, and impaired locomotor behavior, hallmarks of Parkinson's disease (PD)-like neurodegeneration. Dopaminergic neurochemistry was impaired (tyrosine hydroxylase and dopamine decreased), with concomitant reduction of GABA, and locomotor and circadian deficits emerged. Remarkably, co-treatment with the antioxidant N-acetylcysteine (NAC) restored mitochondrial membrane potential, reduced mitochondrial ROS and lipid peroxidation, normalized neutral lipid and MUFA accumulation, and rescued neurotransmitter levels and behavior. Stable-isotope tracing confirmed disrupted TCA cycle flux after NPs exposure that was rescued by NAC. Collectively, these findings reveal lipidomic remodeling as a critical link between environmental NPs exposure and PD-like pathology, highlighting mitochondrial redox-lipid interactions as early determinants and support redox-directed interventions to mitigate risk.
    Keywords:  brain metabolism; global lipidomics; mitochondrial dysfunction; nanoplastics; neurotoxicity
    DOI:  https://doi.org/10.1016/j.freeradbiomed.2026.03.023
  66. Anal Chim Acta. 2026 May 15. pii: S0003-2670(26)00246-1. [Epub ahead of print]1399 345296
       BACKGROUND: Extracellular vesicles (EVs) are stable carriers of molecular signals and can cross the blood-brain barrier, making them promising non-invasive biomarkers for diseases of the central nervous system. While their diagnostic potential is already established and is present in many clinical trials for brain tumors, applications in neurodegenerative disorders such as Parkinson's disease (PD) are still emerging. Although researchers have shown that EVs are involved in the intercellular diffusion of aggregated α-synuclein, a hallmark of PD pathology, the clinical use of EVs as disease biomarkers is still limited by the lack of standardized and selective protocols for EV isolation and analysis.
    RESULTS: Here, we proposed a dual biochemical and spectroscopic approach to selectively detect PD-associated EVs. As a cellular model of dopaminergic neurons, we employed the human neuroblastoma cell line SH-SY5Y differentiated with retinoic acid and then subjected to 6-hydroxydopamine (6-OHDA) insult to mimic PD-like neurodegeneration. Western blot analysis of SH-SY5Y cells exposed to the neurotoxin revealed high-molecular-weight α-synuclein species consistent with oligomeric forms, which are known to be highly toxic and were also detected in EVs. Moreover, a dot-blot assay with selective sensitivity for aggregated α-synuclein revealed its localization on the membrane surface of fresh, intact PD-like-derived EVs. In addition, Fourier transform infrared spectroscopy identified biochemical signatures that may correlate with pathological states, distinguishing EVs carrying aggregated α-synuclein.
    SIGNIFICANCE: By combining these biochemical and spectroscopic methods, which required minimal sample volumes, we were able to selectively identify the class of vesicles carrying the aggregated, toxic-form of α-synuclein. As proof of concept, our findings highlight the diagnostic and non-invasive potential of these biomarkers for distinguishing pathology, supporting their possible use in liquid biopsy for neurodegenerative diseases.
    Keywords:  Biomarker; Exosomes; Extracellular vesicles; Mid-infrared; Neurodegenerative disorder; Parkinson's disease
    DOI:  https://doi.org/10.1016/j.aca.2026.345296
  67. Autophagy. 2026 Mar 09.
      Fibrous dysplasia (FD) is a bone mesenchymal stromal cells (BMSCs)-derived disorder caused by GNAS gene mutation, characterized by excessive fibrous tissue proliferation in bone and the formation of immature trabecular bone. Although impaired osteogenesis of BMSCs is central to FD pathogenesis, the underlying mechanism remains largely elusive. Here we demonstrate that hyperactivation of the cAMP-PRKA/PKA signaling axis disrupts mitochondrial homeostasis through impaired mitophagy, ultimately leading to diminished amorphous calcium phosphate (ACP) secretion and consequent mineralization failure in FD. Mechanistically, in FD BMSCs, PRKA activation inhibits DNM1L/DRP1 recruitment to mitochondria through phosphorylation at S637, thereby suppressing mitochondrial fission. Consequently, excessive mitochondrial fusion leads to an elevated mitochondrial membrane potential, impaired mitophagy, and diminished ACP release. Collectively, our findings reveal a novel signaling nexus linking cAMP-PRKA signaling, mitochondrial dynamics, and biomineralization processes in FD pathogenesis, providing critical insights into the molecular basis of this disorder.
    Keywords:  Amorphous calcium phosphate; biomineralization; cAMP-PRKA pathway; fibrous dysplasia; mitophagy
    DOI:  https://doi.org/10.1080/15548627.2026.2643409
  68. Mol Genet Metab. 2026 Mar 03. pii: S1096-7192(26)00155-1. [Epub ahead of print]148(2): 109872
      Transaldolase deficiency is a rare metabolic disease caused by pathogenic variants in the TALDO1 gene. Transaldolase plays an important role in the ribose-5-phosphate production, maintaining the NADPH-dependent lipid biosynthesis and cellular redox homeostasis. A small number of patients, predominantly children, have been reported, with a wide range of phenotypic presentations, including liver and kidney disease, involvement of the hematopoietic and endocrine systems, as well as possible early death. We aim to provide further insight into the clinical progression of transaldolase deficiency in adolescence and adulthood. We report on three adult patients with genetically confirmed transaldolase deficiency, including two novel genetic variants in TALDO1. Although the patients have been symptomatic since newborn age, initially with hepatomegaly and cytopenias, they were only diagnosed during adolescence or adulthood. Genetic analysis was performed only at 17, 26, and 32 years, respectively, which, however, did not reveal any genetic variants that would be expected to cause a milder disease course. In adulthood, the dominant clinical features were hypergonadotropic hypogonadism, osteopenia, renal and hepatic involvement. In conclusion, when reporting three new adult cases and comparing them with 47 accessible cases from the literature, our findings suggest that, even if clinical manifestations begin in the neonatal period, the overall phenotype may remain relatively mild, with gradual progression. This means that patients presenting with otherwise unexplained progressive liver disease, kidney dysfunction, cytopenia, and hypergonadotropic hypogonadism should be tested for transaldolase deficiency. We recommend closely monitoring patients with known transaldolase deficiency regarding the above-mentioned problems.
    Keywords:  Acute liver failure; Chronic kidney disease; Hypergonadotropic hypogonadism; Pentose phosphate pathway; TALDO1; Transaldolase deficiency
    DOI:  https://doi.org/10.1016/j.ymgme.2026.109872
  69. Mol Genet Metab. 2026 Mar 05. pii: S1096-7192(26)00159-9. [Epub ahead of print]148(2): 109876
       INTRODUCTION: Mitochondrial long-chain fatty acid oxidation (LC-FAO) disorders (LC-FAOD) are inherited metabolic disorders. Real-World-Data (RWD) contributes to Real-World-Evidence (RWE) for LC-FAOD, as prospective natural history studies are difficult due to their incidence of ∼1:10,000.
    MATERIAL AND METHODS: We generated a RWD and developed and validated a clinical severity score.
    RESULTS: 38 patients were included in our RWD (VLCAD n = 7; LCHAD n = 6; CACT n = 3; MAD n = 1; CPT-I n = 14; CPT-II n = 5 and CT n = 2 deficiencies). Our clinical severity score was applied to 14 patients by four independent raters (at the time of diagnosis and on treatment) and compared with an age- and sex-matched control group. Inter-rater reliability was excellent for scores at the time of diagnosis (ICC3k = 0.979 [95% CI: 0.975-0.981]) and on treatment (ICC3k = 0.942 [95% CI: 0.932-0.950]). Using k-means clustering, patients were stratified into mild (0-8), moderate (9- ≤ 14), and severe (≥15) categories. At the time of diagnosis scores were significantly higher compared with control group (p < 0.0001).
    DISCUSSION: Our study provides valuable new RWE with practical clinical applications for LC-FAOD including a RWD and development and validation of a clinical severity score for LC-FAOD. We think that our validated clinical severity score will help for precision therapies to improve patient outcomes in LC-FAOD. Application of our clinical severity score in more patients with LC-FAOD will allow its further validation.
    Keywords:  CPT-II deficiency; Clinical severity score; LCHAD deficiency; Long-chain fatty acid oxidation defects; VLCAD deficiency
    DOI:  https://doi.org/10.1016/j.ymgme.2026.109876
  70. Autophagy. 2026 Mar 08. 1-17
      Neuronal axon regeneration is a complex and coordinated reorganization process that requires the involvement of mitochondria. Here, we demonstrated that FUNDC1 (FUN14 domain containing 1)-mediated mitophagy played a crucial role in determining the intrinsic capacity for axonal regrowth and peripheral nerve recovery. We found that acute nerve injury resulted in the accumulation of impaired mitochondria at the axonal injury site, accompanied by an increase in the expression of the mitophagy receptor FUNDC1. Strikingly, overexpression of FUNDC1 enhanced axonal regeneration both in vitro and in vivo, likely by maintaining a healthy mitochondrial population through mitophagy. Similarly, treatment with urolithin A (UA), a natural mitophagy inducer, promoted axon regrowth after injury. Conversely, fundc1 deletion impaired regeneration, an effect reversed by reintroducing wild type (WT) FUNDC1 in neurons but not an MAP1LC3B/LC3 (microtubule associated protein 1 light chain 3 beta)-interacting region (LIR) mutant. Metabolic profiling further demonstrated that FUNDC1-mediated mitophagy drives dorsal root ganglion (DRG) neurons regeneration through enhanced carnosine biosynthesis. Mechanistically, sciatic nerve injury (SNI) in Fundc1 transgenic (TG) mice upregulated NRF1 (nuclear respiratory factor 1) and PPARGC1A/PGC-1α (PPARG coactivator 1 alpha), which stimulated mitochondrial biogenesis and activated Carns1 (carnosine synthase 1) transcription. This increased carnosine biosynthesis, aiding peripheral nerve recovery through its antioxidant effects. Our findings highlighted FUNDC1-mediated mitophagy as a key mechanism in nerve regeneration, linking mitochondrial quality control, metabolic adaptation, and nerve regeneration.Abbreviations: Δψm: mitochondrial membrane potential; DIV: days in vitro; DRG: dorsal root ganglion; KO: knockout; LIR: LC3-interacting region; P60: postnatal day 60; PNS: peripheral nervous system; PSI: post sciatic nerve injury; ROS: reactive oxygen species; SD: standard deviation; SNI: sciatic nerve injury; TEM: transmission electron microscopy; TG: transgenic; TMRE: tetramethylrhodamine ethylester; UA: urolithin A; WT: wild type.
    Keywords:  Axon regeneration; FUNDC1; NRF1; carnosine; mitochondrial quality; mitophagy
    DOI:  https://doi.org/10.1080/15548627.2026.2629721
  71. Mol Ther. 2026 Mar 11. pii: S1525-0016(26)00180-2. [Epub ahead of print]
      
    DOI:  https://doi.org/10.1016/j.ymthe.2026.02.045
  72. JCI Insight. 2026 Mar 10. pii: e191475. [Epub ahead of print]
      Moderate hyperoxia (30-60% O₂) in premature infants promotes bronchial airway hyperresponsiveness (AHR) via airway smooth muscle (ASM), a key regulator of bronchoconstriction, bronchodilation, and remodeling. Understanding how O2 exposure drives long-term bronchial changes in prematurity is critical for developing therapies for airway disease across the lifespan. Premature lungs have immature antioxidant defenses, potentially due to disrupted mitochondrial dynamics, increasing susceptibility to O2-induced oxidative stress. Thus, mitochondrial homeostasis is highly relevant to ASM dysfunction and airway disease. We propose that hyperoxia in prematurity promotes mitochondrial dysfunction, and that the gasotransmitter hydrogen sulfide (H₂S) mitigates O2-induced mitochondrial damage in developing ASM. Human fetal ASM (fASM) were exposed to moderate hyperoxia to investigate the effects of exogenous H₂S donors (GYY4137, AP39) and stabilization of cystathionine β-synthase (CBS), an H₂S biosynthetic enzyme, on mitochondrial structure and function. Hyperoxia impaired fASM mitochondrial integrity, while H₂S donors in particular, or CBS stabilization attenuated adverse O2 effects on mitochondrial morphology, reactive oxygen species, respiration, calcium regulation, and contractility. These findings highlight the therapeutic potential of H₂S in the premature lung exposed to moderate hyperoxia.
    Keywords:  Asthma; Calcium signaling; Cell biology; Mitochondria; Pulmonology; Therapeutics
    DOI:  https://doi.org/10.1172/jci.insight.191475
  73. J Agric Food Chem. 2026 Mar 09.
      Benzo[a]pyrene (BaP), a ubiquitous polycyclic aromatic hydrocarbon (PAH) present in the environment and food chain, causes severe hepatotoxicity. However, the integrated cell death mechanisms underlying BaP-induced liver injury remain poorly defined. Here, we identify PANoptosis, an integrated cell death program encompassing pyroptosis, apoptosis, and necroptosis, as a central mechanism driving BaP-induced liver injury. In vivo and in vitro experiments revealed that BaP activates pyroptosis via the ROS/NLRP3/Caspase-1/GSDMD axis and necroptosis through the ROS/RIPK1/RIPK3/p-MLKL cascade. Remarkably, we uncovered that the pyroptosis executor GSDMD-N and the necroptosis effector p-MLKL translocated from the plasma membrane to mitochondria, inducing mitochondrial outer membrane permeabilization, cytochrome c release, and subsequent caspase-dependent apoptosis. Silencing either GSDMD or MLKL restored mitochondrial integrity and suppressed PANoptosis. Our work expands the conceptual framework of environmental toxicology by revealing how BaP orchestrates integrated cell death through mitochondrial targeting, offering mechanistic insight and potential therapeutic targets for PAH-induced liver injury.
    Keywords:  GSDMD-N; PANoptosis; benzo[a]pyrene; hepatotoxicity; mitochondrial dysfunction; p-MLKL
    DOI:  https://doi.org/10.1021/acs.jafc.5c15259
  74. Cell Stem Cell. 2026 Mar 05. pii: S1934-5909(26)00073-1. [Epub ahead of print]33(3): 372-381
      Twenty years have passed since the first demonstration of mouse induced pluripotent stem cells (iPSCs). What began as an unexpected observation in Kyoto quickly transformed stem cell biology and regenerative medicine worldwide. Over the past two decades, we have gained profound insights into the molecular mechanisms underlying cellular reprogramming and pluripotency. The technology has continued to evolve-becoming safer, more efficient, and more versatile. Today, iPSCs serve as a foundation for wide-ranging applications, from disease modeling and drug discovery to regenerative therapies and rejuvenation research. In this review, I reflect on the scientific journey of iPSCs, highlight key milestones in our understanding of reprogramming, and discuss the expanding clinical and societal impact of iPSCs.
    Keywords:  iPS cells; medical application; reprogramming
    DOI:  https://doi.org/10.1016/j.stem.2026.02.003
  75. Commun Biol. 2026 Mar 10.
      CRISPR-associated proteins (Cas) are central to gene editing, forming nuclease complexes with guide RNA to enable precise genome modification. Among numerous Cas variants, Cas9 and Cas12a are the most extensively studied. While much is known about the genomic substrates for these enzymes, less is known about the determinants of the DNA cleavage activity. Wild-type Cas12a exhibits higher intrinsic specificity than Cas9, minimizing off-target activity, but lower overall potency. Recent protein engineering has sought to improve both parameters. Here, we shed light on the structural and mechanistic basis by which an engineered AsCas12a variant achieves high potency while retaining its hallmark specificity. We show that reduced protein-DNA interactions facilitate more rapid R-loop formation, thereby enhancing cleavage activity. These results provide mechanistic insight into Cas12a function and highlight strategies for designing genome-editing nucleases with optimal balance between efficiency and specificity.
    DOI:  https://doi.org/10.1038/s42003-026-09799-1
  76. Mol Biol Cell. 2026 Mar 11. mbcE25070334
      It is well established that many tumor types possess defective autophagic pathways. Several studies have reported that the transmembrane, autophagic lipid scramblase ATG9B is altered in multiple cancers, suggesting that this dysregulation could contribute to oncogenesis. Therefore, the goal of this study was to define the cellular distribution of ATG9B in two different tumor cell types and to provide insights into its cellular function. Surprisingly, we found that ATG9B shows a modest association with autophagic structures and exhibits a unique and prominent localization to mitochondria, in contrast to its related form ATG9A. Upon expression of tagged ATG9B forms, this mitochondrial distribution was accompanied by aberrant changes in mitochondrial morphology as well as a reduction in the mitochondrial membrane potential and the release of mtDNA. Few indicators for ATG9B-dependent mitophagy were noted. Instead, ATG9B overexpression led to pronounced apoptotic cell death as assessed by a variety of indicators. Further, we find that the N-terminal sequence of ATG9B acts as a mitochondrial targeting domain and that expression of this peptide alone can induce apoptotic cell death. These findings provide new insights into a putative cellular localization and function for ATG9B. [Media: see text] [Media: see text] [Media: see text].
    DOI:  https://doi.org/10.1091/mbc.E25-07-0334
  77. Physiology (Bethesda). 2026 Mar 12.
      Human brown adipose tissue (BAT) has emerged as a metabolically dynamic organ with the potential to influence thermoregulation, substrate utilization, and cardiometabolic health. This review synthesizes current knowledge on the biomolecular features of human BAT, physiological and pharmacological strategies to stimulate energy dissipation, the tools used to measure its function in vivo, and its role in thermoregulation and metabolic disease. Molecular profiling reveals that human BAT contains heterogeneous thermogenic adipocytes with multilocular lipid droplets, rich innervation and vascularization, compartmentalized mitochondria, and-beyond its hallmark expression of uncoupling protein 1 (UCP1)-the capacity to recruit broader oxidative and futile-cycle pathways. Anatomically, BAT is distributed across several depots with distinct recruitment potential that varies widely between individuals. Cold exposure remains the most potent activator, although nutritional and pharmacological stimuli can also modulate BAT activity. Advances in imaging have expanded the ability to quantify BAT thermogenesis, from gold-standard [15O]O2 and [11C]acetate PET to multi-tracer and multimodal approaches aimed at capturing oxidative flux and heat production. These methods indicate that human BAT contributes modestly to lipid and glucose clearance and whole-body energy expenditure, yet spontaneous uptake of [18F]fluorodeoxyglucose remains consistently associated with lower adiposity and reduced cardiometabolic risk. Major uncertainties persist regarding the true thermogenic capacity of human BAT, the functional relevance of beige adipocytes, the balance between UCP1-dependent and UCP1-independent heat-producing pathways, and the most reliable metrics of in vivo activation. Addressing these known unknowns will require integrated, multimodal approaches to define when, where, and how human BAT contributes to metabolic health.
    Keywords:  Brown adipose tissue; adipose tissues; thermogenesis; thermogenic adipocytes; thermoregulation
    DOI:  https://doi.org/10.1152/physiol.00002.2026
  78. J Clin Med. 2026 Mar 09. pii: 2070. [Epub ahead of print]15(5):
       BACKGROUND: HyperCKemia, defined as elevated serum creatine kinase, commonly reflects muscle injury but may also indicate underlying metabolic disease. Metabolic aetiologies, including glycogen storage disorders, fatty acid oxidation defects, mitochondrial cytopathies, and purine metabolism disorders, are clinically important owing to diagnostic complexity, therapeutic implications, and potential reversibility.
    OBJECTIVE: To summarise current evidence on metabolic causes of hyperCKemia in adults, with emphasis on disorders of carbohydrate, lipid, and purine metabolism and mitochondrial disease.
    METHODS: Semi-systematic narrative review of pathophysiology, clinical features, diagnostic approaches, and management of metabolic disorders associated with hyperCKemia.
    RESULTS: Metabolic myopathies often present with nonspecific or exercise-related symptoms, with creatine kinase levels ranging from mild-to-severe elevations. Conditions such as McArdle disease, carnitine palmitoyltransferase II deficiency, and mitochondrial cytopathies demonstrate characteristic metabolic vulnerabilities leading to episodic or persistent hyperCKemia. Medications, including statins and antiretrovirals, may precipitate symptoms in predisposed individuals. Diagnosis requires a structured, multidisciplinary approach incorporating biochemical testing, genetic analysis, functional studies, and muscle biopsy. Many causes are amenable to targeted therapy, including dietary modification, endocrine correction, and medication withdrawal.
    CONCLUSION: Metabolic causes of hyperCKemia are under-recognised but clinically significant. Early identification allows targeted treatment and prevention of complications.
    Keywords:  creatine kinase; exercise intolerance; fatty acid oxidation disorders; glycogen storage disease; mitochondrial disease; rhabdomyolysis
    DOI:  https://doi.org/10.3390/jcm15052070
  79. Front Mol Biosci. 2026 ;13 1752024
      Non-alcoholic fatty liver disease (NAFLD) is increasingly recognized as a mitochondrial-driven metabolic disorder, yet the specific contributions of individual mitochondrial respiratory chain complexes remain poorly defined. In particular, inconsistent alterations in complexes I-V have been reported across different NAFLD models, representing a critical knowledge gap. Here, we systematically reviewed in vivo and in vitro studies to evaluate changes in mitochondrial complexes I-V during NAFLD progression. Overall, NAFLD is commonly associated with reduced complex activity, impaired mitochondrial respiration, and increased reactive oxygen species production. Notably, a subset of studies reported enhanced complex activity and respiration, suggesting context-dependent mitochondrial adaptations. This synthesis clarifies divergent findings and highlights mitochondrial respiratory complexes as dynamic and therapeutically relevant targets for future NAFLD intervention strategies.
    Keywords:  energy metabolism; lipid metabolism; mitochondrial complexes; non-alcoholic fatty liver disease (NAFLD); redox homeostasis
    DOI:  https://doi.org/10.3389/fmolb.2026.1752024