bims-auttor Biomed News
on Autophagy and mTOR
Issue of 2025–03–09
fifty-six papers selected by
Viktor Korolchuk, Newcastle University
  1. Neuroglobin regulates autophagy through mTORC1/RAPTOR/ULK-1 pathway in human neuroblastoma cells.
  2. To degrade or not to degrade: how phase separation modulates selective autophagy.
  3. A narrative review of autophagy in migraine.
  4. Mitochondrial accumulation and lysosomal dysfunction result in mitochondrial plaques in Alzheimer's disease.
  5. Targeted Degradation Technology Based on the Autophagy-Lysosomal Pathway: A Promising Strategy for Treating Preeclampsia.
  6. Dynamic regulation of autophagy during Semliki Forest virus infection of neuroblastoma cells.
  7. Autophagy-dependent versus autophagy-independent ferroptosis.
  8. PPTC7 acts as an essential co-factor of the SCFFBXL4 ubiquitin ligase complex to restrict BNIP3/3L-dependent mitophagy.
  9. TSC2 loss in neural progenitor cells suppresses mRNA translation of neurodevelopmental genes.
  10. Leucine accelerates atherosclerosis through dose-dependent MTOR activation in macrophages.
  11. Methionine is an essential amino acid in doxorubicin-induced cardiotoxicity through modulating mitophagy.
  12. Vacuoles provide the source membrane for TORC1-containing signaling endosomes.
  13. Mitochondrial proteostasis and cellular health: insights from chaperones and autophagy.
  14. LncRNA HITT inhibits autophagy by attenuating ATG12-ATG5-ATG16L1 complex formation.
  15. Treponema pallidum Flagellin FlaB3 Activates Inflammation and Inhibits Autophagy in HMC3 Cells via the TLR4 Pathway.
  16. DNLA Delayed the Appearance of Learning and Memory Impairment of APP/PS1 Mice: Involvement of mTOR/TFEB/v-ATPase Signaling Pathway.
  17. Recent advances in the clinical spectrum and pathomechanisms associated with X-linked myopathy with excessive autophagy and other VMA21-related disorders.
  18. Cleavage of the selective autophagy receptor NBR1 by the PDCoV main protease NSP5 impairs autophagic degradation of the viral envelope protein.
  19. Adaptor-Mediated Trafficking of Tank Binding Kinase 1 During Diverse Cellular Processes.
  20. SNX10 functions as a modulator of piecemeal mitophagy and mitochondrial bioenergetics.
  21. Clemastine attenuates subarachnoid haemorrhage pathology in a mouse model via Nrf2/SQSTM1-mediated autophagy.
  22. Role of the USP family in autophagy regulation and cancer progression.
  23. Apatinib inhibits HTNV by stimulating TFEB-driven lysosome biogenesis to degrade viral protein.
  24. Intracerebellar upregulation of Rheb(S16H) ameliorates motor dysfunction in mice with SCA2.
  25. Trophoblast-specific Deptor knockdown enhances trophoblast nutrient transport and fetal growth in mice.
  26. Coordinated Role of Autophagy and ERAD in Maintaining Neuroendocrine Function by Preventing Prohormone Aggregation.
  27. Double Prenylation of Budding Yeast Ykt6 Regulates Cell Wall Integrity and Autophagy.
  28. Metformin alleviates auditory cell senescence by mitophagy induction.
  29. A long-lived pool of PINK1 imparts a molecular memory of depolarization-induced activity.
  30. Caspase cleavage of influenza A virus M2 disrupts M2-LC3 interaction and regulates virion production.
  31. Novel reporter of the PINK1-Parkin mitophagy pathway identifies its damage sensor in the import gate.
  32. Mitochondria at the crossroads: Quality control mechanisms in neuronal senescence and neurodegeneration.
  33. CHOP aggravates hepatocyte apoptosis upon endoplasmic reticulum stress by down-regulating autophagy.
  34. Enhanced SIRT3 expression restores mitochondrial quality control mechanism to reverse osteogenic impairment in type 2 diabetes mellitus.
  35. The compound XueShuanTong promotes podocyte mitochondrial autophagy via the AMPK/mTOR pathway to alleviate diabetic nephropathy injury.
  36. MTCH2 Suppresses Thermogenesis by Regulating Autophagy in Adipose Tissue.
  37. PPDPF-mediated regulation of BCAA metabolism enhances mTORC1 activity and drives cholangiocarcinoma progression.
  38. miR-21 regulates autophagy and apoptosis of ectopic endometrial stromal cells of adenomyosis via PI3K/ AKT/ mTOR pathway.
  39. Leucyl-tRNA Synthetase Regulates Casein Synthesis in Dairy Cows via the mTORC1-LAT1 Pathway.
  40. Mitochondrial Dysfunction in Alzheimer's Disease.
  41. Compression force regulates cementoblast mineralization via S1PR1/mitophagy axis.
  42. Innate immune responses to lysosomal nucleic acid stress.
  43. Bulky substrates of isoleucine 2-epimerase: α-Neopentylglycine and NV-5138.
  44. Urolithin A provides cardioprotection and mitochondrial quality enhancement preclinically and improves human cardiovascular health biomarkers.
  45. The role of the poly(A) binding protein-binding protein MoPbp1 as a regulator of the TOR signaling pathway in growth, autophagy, and pathogenicity of the rice blast fungus.
  46. Circadian Control of Hepatic Ischemia/Reperfusion Injury via HSD17B13-Mediated Autophagy in Hepatocytes.
  47. Microglial APOE4 promotes neuron degeneration in Alzheimer's disease through inhibition of lipid droplet autophagy.
  48. Axonal transport of CHMP2b is regulated by kinesin-binding protein and disrupted by CHMP2bintron5.
  49. CHIP protects lysosomes from CLN4 mutant-induced membrane damages.
  50. The ROGDI protein mutated in Kohlschutter-Tonz syndrome is a novel subunit of the Rabconnectin-3 complex implicated in V-ATPase assembly.
  51. Important regulatory role of mitophagy in diabetic microvascular complications.
  52. Astragalin actives autophagy and inhibits apoptosis of astrocytes in AD mice via down-regulating Fas/Fasl-VDAC1 pathway.
  53. Protective role of mitophagy on microglia-mediated neuroinflammatory injury through mtDNA-STING signaling in manganese-induced parkinsonism.
  54. Rejuvenation of Senescent Cells, In Vitro and In Vivo, by Low-Frequency Ultrasound.
  55. Loss of TC-PTP in keratinocytes leads to increased UVB-induced autophagy.
  56. AMPK phosphosite profiling by label-free mass spectrometry reveals a multitude of mTORC1-regulated substrates.
  1. Sci Rep. 2025 Mar 04. 15(1): 7642
    Neuroglobin regulates autophagy through mTORC1/RAPTOR/ULK-1 pathway in human neuroblastoma cells.
    Valeria Manganelli, Michele Costanzo, Daniela Caissutti, Illari Salvatori, Niccolò Candelise, Emiliano Montalesi, Giovanna De Simone, Alberto Ferri, Tina Garofalo, Maurizio Sorice, Margherita Ruoppolo, Agostina Longo, Roberta Misasi.
      Neuroglobin (NGB) is a hexacoordinated hemeprotein mainly expressed in neurons. Following its upregulation and mitochondrial localization, NGB plays a pro-survival role against neuronal stress. Previously, we built a stable NGB-FLAG-overexpressing neuroblastoma cell line and showed that NGB promotes autophagy and localizes in autophagolysosomes. Here we studied the interactome of NGB-FLAG cells to identify novel autophagy-related NGB-binding partners and investigate how its upregulation could induce autophagy. LC3-II and p62 levels as well as mTORC1 activity were analyzed to evaluate autophagy in NGB-FLAG cells. NGB interactors were identified by affinity purification-mass spectrometry and protein-protein interaction network analysis and validated by immunoprecipitation. The increase of LC3-II and decrease of p62 in NGB-FLAG compared to control confirmed that NGB overexpression promotes autophagy. Interactome analysis identified the Regulatory associated protein of mTOR (RPTOR) as one of 134 putative NGB interactors, further validated by immunoprecipitation. NGB overexpression also determined a consistent increment of RPTOR phosphorylation at Ser792 which is required for mTORC1 inhibition, then confirmed by lower levels of phospho-mTOR and phospho-ULK1 in NGB-FLAG compared to control. Collectively, our data suggests that NGB is a positive regulator of autophagy. Through association with RPTOR, NGB may promote its activation and inhibit mTORC1 repressive activity on autophagy initiation.
    Keywords:  Autophagy; Neuroblastoma cells; Neuroglobin; Raptor
    DOI:  https://doi.org/10.1038/s41598-025-91701-w
  2. Autophagy. 2025 Mar 07.
    To degrade or not to degrade: how phase separation modulates selective autophagy.
    Mariya Licheva, Riccardo Babic, Jeremy Pflaum, Hector Mancilla, Florian Wilfling, Claudine Kraft.
      Selective macroautophagy/autophagy relies on newly formed double-membrane compartments, known as phagophores, to sequester and recycle diverse cellular components, including organelles, biomolecular condensates and protein aggregates, maturing into autophagosomes that fuse with the vacuole/lysosome. Autophagosomes originate at the cargo-vacuole/ER interface, where autophagy factors assemble into the phagophore assembly site (PAS). However, how autophagy proteins organize on the surface of structurally and biophysically different cargoes, and achieve spatial confinement at the PAS to support autophagosome formation remains unclear. Mechanisms governing cargo selection are also poorly understood. In this study, we demonstrate that receptor mobility, driven by low affinity cargo-receptor interactions, is crucial for rendering cellular structures degradable by autophagy. We show that cargo surface mobility, combined with the phase separation of scaffold proteins, drives the formation of early PAS precursors, termed "initiation hubs". These hubs dynamically rearrange at the cargo-vacuole/ER interface to promote autophagosome biogenesis, providing new insights into selective autophagy initiation.
    Keywords:  Aggrephagy; Atg11/RB1CC1; autophagy; cargo receptor; initiation hub, phase separation
    DOI:  https://doi.org/10.1080/15548627.2025.2476025
  3. Front Neurosci. 2025 ;19 1500189
    A narrative review of autophagy in migraine.
    Yanan Huang, Hongyan Li, Qijun Yu, Yonghui Pan.
       Background and objective: Autophagy is a natural process regulated by autophagy-related genes in eukaryotic cells that involves the degradation of cytoplasmic proteins and old or damaged organelles via the lysosomal pathway to help maintain cell homeostasis. Previous studies have suggested a potential association between autophagy and migraine, while the underlying mechanisms remain unclear. This review seeks to evaluate the possible involvement of autophagy in the pathophysiology of migraine, aiming to clarify its role and implications for future research and therapeutic strategies.
    Methods: A search in PubMed was conducted for English-language articles until December 5, 2024. Key terms of "autophagy," "migraine," "microglia," "neurogenic inflammation," "central sensitization," "mitophagy" and "neuropathic pain" in different combinations.
    Results: In the context of migraine, the activation of the phosphoinositide 3-kinase (PI3K)/protein kinase B (PKB/Akt) signaling pathway exerts a direct influence on the mammalian target of rapamycin (mTOR), leading to a reduction in autophagy levels. Moreover, the stimulation of purinergic ligand-gated ion channel type 7 receptor (P2X7R) in microglia can hinder autophagy by interfering with the fusion of autophagosomes and lysosomes, which impedes the degradation of substrates within the autophagolysosome. Increased levels of calcitonin gene-related peptide (CGRP) may also modulate autophagy through the Akt/mTOR or protein kinase A (PKA)/mTOR signaling pathways. Additionally, research indicates that mitophagy may be partially impaired in individuals suffering from migraine. Furthermore, autophagy could contribute to the dysregulation of synaptic plasticity by influencing the processes of long-term potentiation (LTP) and long-term depression (LTD), both of which are associated with central sensitization in chronic migraine.
    Conclusion: These findings suggest that autophagy may play an important role in the pathophysiology of migraine, particularly in its development and central sensitization. Research on autophagy modulators related to migraine will provide valuable insights for treatment strategies.
    Keywords:  P2X7R; PI3K/Akt pathway; autophagy; central sensitization; migraine
    DOI:  https://doi.org/10.3389/fnins.2025.1500189
  4. bioRxiv. 2025 Feb 20. pii: 2025.02.19.639081. [Epub ahead of print]
    Mitochondrial accumulation and lysosomal dysfunction result in mitochondrial plaques in Alzheimer's disease.
    Xiuli Dan, Deborah L Croteau, Wenlong Liu, Xixia Chu, Paul D Robbins, Vilhelm A Bohr.
      Dysfunctional mitophagy is a key component of Alzheimer's disease (AD) pathology, yet direct in vivo evidence and mechanistic insights remain limited. Using a mitophagy reporter in an AD mouse model ( APP / PSEN1 /mt-Keima), we identified mitochondrial plaques (MPs) composed of accumulated mitochondria within or outside lysosomes in AD, but not normal mouse brains. Similar structures were also found in AD human brains, but not in healthy controls. Abnormal mitochondrial accumulation in dystrophic neurites, defective mitophagy, and impaired lysosomal function disrupted proper mitochondrial degradation, resulting in excessive mitochondria accumulation both within and outside autophagic vesicles. The resulting intensive mitochondria-containing neurites coalesce into MPs, which co-develop with amyloid plaques to form mixed plaques. These findings establish MPs as novel pathological entity and a promising therapeutic target in AD.
    DOI:  https://doi.org/10.1101/2025.02.19.639081
  5. Am J Reprod Immunol. 2025 Mar;93(3): e70066
    Targeted Degradation Technology Based on the Autophagy-Lysosomal Pathway: A Promising Strategy for Treating Preeclampsia.
    Lin Xiao, Zilin Mei, Jin Chen, Kai Zhao, Huiping Zhang, Surendra Sharma, Aihua Liao, Chunyan Liu.
      In recent years, targeted protein degradation (TPD) strategies leveraging the autophagy-lysosomal pathway (ALP) have transcended the limitations of conventional drug molecules, emerging as a highly promising approach for selectively eliminating disease-related proteins via the cell's intrinsic degradation machinery. These TPD methods, such as autophagosome-tethering compounds (ATTEC), autophagy-targeting chimera (AUTAC), AUTOphagy-TArgeting chimera (AUTOTAC), and chaperone-mediated autophagy (CMA) targeting chimera, exhibit efficacy in degrading misfolded protein aggregates associated with neurodegenerative disorders. Moreover, the excessive accumulation of misfolded proteins or protein complexes in the placenta has been identified as a significant contributor to preeclampsia (PE). Given the lack of effective treatments for PE, the application of autophagy-mediated TPD technology presents a novel therapeutic avenue. This review draws parallels between misfolded protein aggregates in neurodegenerative diseases and placenta-derived PE, integrating a substantial number of full-text studies. By harnessing TPD technologies grounded in the ALP, these autophagic degraders offer a pioneering approach for targeted therapy in PE by dismantling potential targets. Presently, there is limited exploration of ALP technology for identifying target proteins in the placenta. Nonetheless, we have proposed several potential target proteins, laying the groundwork for future therapeutic endeavors.
    Keywords:  ATTEC; AUTAC; AUTOTAC; CMA; TPD; preeclampsia
    DOI:  https://doi.org/10.1111/aji.70066
  6. J Gen Virol. 2025 Mar;106(3):
    Dynamic regulation of autophagy during Semliki Forest virus infection of neuroblastoma cells.
    Robert J Stott-Marshall, Craig McBeth, Thomas Wileman.
      Autophagy can defend against infection by delivering viruses to lysosomes for degradation. Semliki Forest virus (SFV) is a positive-sense, single-stranded RNA virus of the alphavirus genus which has been used extensively as a model for arbovirus infection and neuronal encephalitis. Here, we show that autophagy is suppressed during the early hours of SFV infection of neurons. We also show that a switch between autophagy suppression and upregulation between the early and later stages was mediated through modulation of the mammalian target of rapamycin (mTOR) activity during infection. At later stages of infection, autophagosomes colocalize with SFV nonstructural proteins suggesting the formation of a platform for virus replication. Inhibition of mTOR by torin reduced infectious virus production and intracellular virus gene expression while improving cell survival during infection. The results suggest that autophagy is suppressed early during infection of neurons to increase cell survival and then upregulated at later times to facilitate replication. This biphasic regulation of autophagy seen for SFV may be important for other arboviruses, and knowledge about the regulation of autophagy by alphaviruses may be useful for the development of antiviral therapies.
    Keywords:  Togaviridae; alphavirus; autophagy regulation; mTOR; neurons; ssRNA virus
    DOI:  https://doi.org/10.1099/jgv.0.002086
  7. Trends Cell Biol. 2025 Mar 05. pii: S0962-8924(25)00005-4. [Epub ahead of print]
    Autophagy-dependent versus autophagy-independent ferroptosis.
    Ye Zhu, Motoki Fujimaki, David C Rubinsztein.
      Ferroptosis is an iron-dependent cell death pathway that, until recently, has been considered to be dependent on autophagy. However, recent studies have reported conflicting results, raising the question about which cell contexts determine the roles of autophagy in ferroptosis. This opinion article addresses this question by summarizing the contexts and/or diseases in which autophagy is a driver or suppressor of ferroptosis. The execution of ferroptosis depends on levels of (labile) iron, unsaturated (phospho)lipids and free radicals. We propose that the cell context in which these three factors and/or their upstream pathways are differentially regulated dictates whether autophagy positively or negatively regulates ferroptosis.
    Keywords:  autophagy; ferroptosis; iron; lysosome; polyunsaturated phospholipid; tissue-specificity
    DOI:  https://doi.org/10.1016/j.tcb.2025.01.005
  8. Cell Death Dis. 2025 Mar 01. 16(1): 145
    PPTC7 acts as an essential co-factor of the SCFFBXL4 ubiquitin ligase complex to restrict BNIP3/3L-dependent mitophagy.
    Xiayun Xu, Yingji Chen, Siqi Fei, Xinyue Jiang, Xiaoting Zhou, Yimeng Xue, Yao Li, Shi-Min Zhao, Yan Huang, Chenji Wang.
      Mitophagy is a selective process that targets the damaged, dysfunctional, or superfluous mitochondria for degradation through autophagy. The SCFFBXL4 E3 ubiquitin ligase complex suppresses basal mitophagy by targeting BNIP3 and BNIP3L, two key mitophagy cargo receptors, for ubiquitin-proteasomal degradation. FBXL4 loss-of-function mutations lead to excessive BNIP3/3L-dependent mitophagy, thereby causing a devastating multi-system disorder called mitochondrial DNA depletion syndrome, type 13 (MTDPS13). PPTC7, a mitochondrial matrix phosphatase, is essential for proper mitochondrial function and biogenesis. Here, we show that a proportion of PPTC7 is located on the outer mitochondrial membrane, where it interacts with FBXL4 and BNIP3/3L. PPTC7 decreases BNIP3/3L protein stability in a protein phosphatase activity-independent manner. Using in vitro cell culture and Pptc7 knockout mouse model, we demonstrate that PPTC7 deficiency activates high levels of basal mitophagy in a BNIP3/3L-dependent manner. Mechanistically, PPTC7 facilitates SCFFBXL4-mediated ubiquitin-proteasomal degradation of BNIP3/3L. Overall, these findings establish PPTC7 as an essential co-factor of the SCFFBXL4 complex and a suppressor of BNIP3/3L-dependent mitophagy.
    DOI:  https://doi.org/10.1038/s41419-025-07463-w
  9. Brain. 2025 Mar 03. pii: awaf081. [Epub ahead of print]
    TSC2 loss in neural progenitor cells suppresses mRNA translation of neurodevelopmental genes.
    Pauline Martin, Krzysztof J Szkop, Francis Robert, Srirupa Bhattacharyya, Roberta L Beauchamp, Jacob Brenner, Nicholas E Redmond, Sidong Huang, Serkan Erdin, Ola Larsson, Vijaya Ramesh.
      Tuberous sclerosis complex (TSC) is an inherited multi-system neurocutaneous disorder where patients often present with neurodevelopmental manifestations such as epilepsy and TSC-associated neuropsychiatric disorder (TAND) that includes autism spectrum disorder (ASD). TSC is caused by inactivating mutations in TSC1 or TSC2 tumor suppressor genes, with encoded proteins hamartin (TSC1) and tuberin (TSC2) forming a functional complex inhibiting mechanistic target of rapamycin complex 1 (mTORC1) signaling. This has led to treatment with allosteric mTORC1 inhibitor rapamycin analogs ("rapalogs") for TSC tumors; however, rapalogs are ineffective for treating neurodevelopmental manifestations. mTORC1 signaling controls protein synthesis by regulating formation of the eIF4F complex, with further modulation by MNK1/2 kinases via phosphorylation of the eIF4F subunit eIF4E. While both these pathways modulate translation, comparing their impact on transcriptome-wide mRNA translation, as well as effects of inhibiting these pathways in TSC has not been explored. Employing CRISPR-modified, isogenic neural progenitor cells (NPCs) derived from a female TSC2 patient, we have examined alterations in early neurodevelopmental phenotypes including proliferation and neurite outgrowth, as well as ability of bi-steric mTORC1-specific inhibitor RMC-6272 to rescue these phenotypes. Further, we utilized polysome-profiling to examine transcriptome-wide changes in mRNA translation upon TSC2 loss and tested effects of treatment with RMC-6272 or MNK1/2-specific inhibitor eFT-508. Our results reveal that altered early neurodevelopmental phenotypes can be rescued upon treatment with RMC-6272, but not rapamycin. We also discovered dysregulated mRNA translation in TSC2-Null NPCs, which significantly overlaps with the translatome from TSC1-Null NPCs. Interestingly, numerous non-monogenic ASD-, NDD- and epilepsy-associated genes identified in patients harboring putative loss-of-function mutations, were translationally suppressed in TSC2-Null NPCs. Importantly, translation of these ASD- and NDD-associated genes was reversed upon inhibition of either mTORC1 or MNK1/2 signaling using RMC-6272 or eFT-508, respectively. This study establishes the importance of mTORC1-eIF4F- and MNK-eIF4E-sensitive mRNA translation in TAND, ASD and other neurodevelopmental disorders laying the groundwork for evaluating drugs in clinical development that target these pathways as a treatment strategy for these disorders.
    Keywords:  4E-BP1; 5’UTR; CNS; S6K1; protein synthesis; rapalogs
    DOI:  https://doi.org/10.1093/brain/awaf081
  10. Autophagy. 2025 Mar 06.
    Leucine accelerates atherosclerosis through dose-dependent MTOR activation in macrophages.
    Xiangyu Zhang, Ali Ajam, Ziyang Liu, Doureradjou Peroumal, Saifur R Khan, Babak Razani.
      The role of diet in driving cardiovascular disease (CVD) is well-recognized, particularly in the case of lipids. Dietary protein on the other hand has been heralded as an overall metabolically beneficial nutrient with popularity in the fitness community and in weight-loss regimens. Pursuant to epidemiological studies raising a CVD risk signal for excessive protein intake, we initially conducted murine studies establishing an atherogenic role for dietary protein, the critical involvement of macrophage MTORC1 signaling, and downstream inhibition of protective macroautophagy/autophagy pathways. In recent work, we confirm these findings in monocytes from humans consuming protein and dissect the MTORC1-autophagy cascade in human macrophages. We also identify leucine as the single most important amino acid, observing dose-dependent activation of MTOR whereby only leucine concentrations above a threshold trigger pathogenic signaling and monocyte/macrophage dysfunction. Using mouse models fed diets with modulated protein and leucine content, we confirm this threshold effect in driving atherosclerosis. Our findings establish a pathogenic role for dietary leucine in CVD and raise the promise of therapeutic strategies aimed at selective inhibition of macrophage leucine-MTOR signaling.
    Keywords:  Atherosclerosis; MTOR; autophagy; dietary protein; leucine; macrophage
    DOI:  https://doi.org/10.1080/15548627.2025.2474603
  11. Free Radic Biol Med. 2025 Mar 01. pii: S0891-5849(25)00127-3. [Epub ahead of print]232 28-39
    Methionine is an essential amino acid in doxorubicin-induced cardiotoxicity through modulating mitophagy.
    Yijun Xin, Yong Zhang, Zhaoji Yuan, Siying Li.
      Doxorubicin (Dox) is a widely used anticancer drug. However, its time- and dose-dependent side effects, particularly severe cardiotoxicity, limit its clinical use. Understanding the molecular mechanisms underlying Dox-induced cardiotoxicity has become a research focus in recent years. Among these, impaired mitophagy which participated in the process of damaged mitochondria clearance, is considered one of the key mechanisms in Dox-induced cardiomyopathy. Methionine (Met) is an essential amino acid that plays a crucial role in various biological processes. This study aims to investigate the role and mechanism of Met in regulating mitophagy in Dox-induced cardiotoxicity. Met deficiency exacerbated Dox-induced cardiotoxicity, primarily by promoting oxidative stress, affecting mitochondria integrity, disrupting autophagy, and thus leading to cardiomyocyte damage and aggravating heart failure. In addition, Met supplementation alleviated Dox-induced cardiotoxicity, via the general control nonderepessible 2 (GCN2) pathway. This study extends our understanding of the relationship between amino acid metabolism and Dox-induced cardiotoxicity, and indicating the Met-GCN2 axis as a promising therapeutic strategy for Dox-induced cardiotoxicity.
    Keywords:  Cardiotoxicity; Doxorubicin; Methionine; Mitophagy
    DOI:  https://doi.org/10.1016/j.freeradbiomed.2025.02.044
  12. J Cell Biol. 2025 May 05. pii: e202407021. [Epub ahead of print]224(5):
    Vacuoles provide the source membrane for TORC1-containing signaling endosomes.
    Kenji Muneshige, Riko Hatakeyama.
      Organelle biogenesis is fundamental to eukaryotic cell biology. Yeast signaling endosomes were recently identified as a signaling platform for the evolutionarily conserved Target of Rapamycin Complex 1 (TORC1) kinase complex. Despite the importance of signaling endosomes for TORC1-mediated control of cellular metabolism, how this organelle is generated has been a mystery. Here, we developed a system to induce synchronized de novo formation of signaling endosomes, enabling real-time monitoring of their biogenesis. Using this system, we identify vacuoles as a membrane source for newly formed signaling endosomes. Membrane supply from vacuoles is mediated by the CROP membrane-cutting complex, consisting of Atg18 PROPPIN and retromer subunits. The formation of signaling endosomes requires TORC1 activity, suggestive of a tightly regulated process. This study unveiled the first mechanistic principles and molecular participants of signaling endosome biogenesis.
    DOI:  https://doi.org/10.1083/jcb.202407021
  13. J Physiol. 2025 Mar 06.
    Mitochondrial proteostasis and cellular health: insights from chaperones and autophagy.
    Yuvraj Anandrao Jagtap, Akash Choudhary, Sumit Kinger, Prashant Kumar, Sudipta Bhattacharyya, Hem Chandra Jha, Rohan Dhiman, Vivek Sharma, Anil K Suresh, Krishna Mohan Poluri, Amit Mishra.
      Mitochondria are a cell's powerhouse and also have a vital part in cellular processes. The emerging role of mitochondria in several crucial processes highlights their cellular and physiological importance. Mitochondrial homeostasis mechanisms, including proteostasis pathways, are vital for mitochondrial health. Failure of these processes has an important role in establishment of numerous complex disease conditions, such as neurodegeneration and imperfect ageing. However, details of mitochondrial impairments and their contribution to the pathology of neurodegeneration are poorly understood. This review systematically discusses the involvement of mitochondrial homeostasis mechanisms and their role in rejuvenating cellular health and fitness. We also focus on various cellular protein quality control mechanisms essential for mitochondrial proteostasis and how their failure leads to mitochondrial functional disturbances observed in disease conditions. We discuss recent findings based on mitostasis-associated chaperones, mitoproteases, and autophagy responses, which can lead to emergence of new possible therapeutic interventions against complex diseases.
    Keywords:  chaperones; mitochondrial dynamics; mitochondrial homeostasis; mitophagy; mitoproteases; neurodegeneration; proteostasis
    DOI:  https://doi.org/10.1113/JP287635
  14. Cancer Lett. 2025 Feb 27. pii: S0304-3835(25)00096-5. [Epub ahead of print]616 217532
    LncRNA HITT inhibits autophagy by attenuating ATG12-ATG5-ATG16L1 complex formation.
    Hao Liu, Xingwen Wang, Bolun Li, Zhiyuan Xiang, Yanan Zhao, Minqiao Lu, Qingyu Lin, Shanliang Zheng, Tianqi Guan, Yihong Zhang, Ying Hu.
      Dysregulated autophagy has been implicated in the pathogenesis of numerous diseases, including cancer. Despite extensive research on the underlying mechanisms of autophagy, the involvement of long non-coding RNAs (lncRNAs) remains poorly understood. Here, we demonstrate that a previously identified lncRNA, HITT (HIF-1α inhibitor at the translation level), is closely associated with biological processes such as autophagy through unbiased bioinformatic analysis. Subsequent studies demonstrate that HITT is increased by several autophagic stimuli, including PI-103, a potent inhibitor of PI3K and mTOR. This is caused by a reduction in the binding between HITT and AGO2, resulting in a reduction in the activity of miR-205 towards HITT degradation. Increased HITT then binds to a key autophagy protein, Autophagy-related 5 (ATG5), and inhibits autophagosome formation by preventing the formation of the ATG12-ATG5-ATG16L1 complex. This results in HITT sensitizing PI-103-mediated cell death both in vitro and in vivo in nude mice by attenuating protective autophagy. The data presented herein demonstrate that HITT is a newly identified RNA regulator of autophagy and that it can be used to sensitize the colon cancer response to cell death by blocking the protective autophagy.
    Keywords:  AGO2; Autophagy; Autophagy-related 5 (ATG5); HIF-1α inhibitor at translation level (HITT); PI-103
    DOI:  https://doi.org/10.1016/j.canlet.2025.217532
  15. ACS Infect Dis. 2025 Mar 04.
    Treponema pallidum Flagellin FlaB3 Activates Inflammation and Inhibits Autophagy in HMC3 Cells via the TLR4 Pathway.
    Fangzhi Du, Zhiyu Lu, Qingyun Wu, Xu Zhang, Xiaoli Zheng, Ruili Zhang, Qianqiu Wang.
      Neurosyphilis, a neurological manifestation of syphilis, is closely related to neuroinflammation. Autophagy, a fundamental cellular mechanism that mediates the degradation of intracellular components, plays a crucial role in immune regulation and inflammation. Microglia, resident immune cells in the brain, are central to these processes. However, the interplay between autophagy and neuroinflammation in the context of neurosyphilis remains poorly understood. In this research, the recombinant Treponema pallidum flagellin, FlaB3, was constructed to treat human microglia clone 3 (HMC3) cells and HMC3 cells in which TLR4 (Toll-like receptor 4) had been knocked down. We discovered that FlaB3 promotes IL-6 and IL-8 secretion through the TLR4 pathway. We also observed that FlaB3 regulates the expression of autophagy-related proteins Beclin1, LC3B, and P62 via the TLR4/PI3K/AKT/mTOR pathway, thereby inhibiting autophagy and autophagic flux in HMC3 cells. Subsequently, we discovered that the concentration of soluble amyloid β1-42 (Aβ1-42) was decreased in the cerebrospinal fluid of neurosyphilis patients. Immunofluorescence analysis further revealed that FlaB3 suppresses the degradation of Aβ by autophagosomes in HMC3 cells. Additionally, treatment with the autophagy activators Rapamycin and LY294002 decreased the levels of IL-6 and IL-8 secretion, indicating that autophagy modulates inflammation in HMC3 cells. In summary, our study demonstrates that FlaB3 promotes inflammation in HMC3 cells by inhibiting autophagy. This inhibition also impedes Aβ degradation, providing new insights into the pathogenesis of neurosyphilis.
    Keywords:  amyloid-β; autophagy; flagellin FlaB3; neuroinflammation; neurosyphilis
    DOI:  https://doi.org/10.1021/acsinfecdis.4c01064
  16. CNS Neurosci Ther. 2025 Mar;31(3): e70300
    DNLA Delayed the Appearance of Learning and Memory Impairment of APP/PS1 Mice: Involvement of mTOR/TFEB/v-ATPase Signaling Pathway.
    Yajuan Wu, Xuejia Liu, Guohui Luo, Qiye Li, Bin Guo, Lisheng Li, Jing Nie.
       INTRODUCTION: Alzheimer's disease (AD) is a progressive neurodegenerative disorder with cognitive impairment that currently is incurable. There is existing evidence to suggest that vacuolar adenosine triphosphatase (v-ATPase) is one of the early key driving factors in the pathological process of AD. Thus, early intervention of v-ATPase may be a viable strategy.
    AIMS: Observing whether early intervention with DNLA can delay learning and memory impairment in mice, and further exploring the mechanism of DNLA delaying AD in vitro based on v-ATPase.
    METHODS: Four-month-old APP/PS1 transgenic mice were treated with alkaloids from Dendrobium nobile Lindl (DNLA) 20 and 40 mg/kg/day for 5 months. The Morris water maze test and nest test showed that DNLA administration significantly delayed the appearance of cognitive deficits in APP/PS1 mice. We further investigated the mechanism of DNLA promoting lysosome acidification in vitro by using PC12 cells.
    RESULTS: We found that DNLA increases the degradation of β-amyloid (Aβ) contained in the autophagic lysosomes and alleviates the aging of neurons by promoting lysosome acidification and improving autophagy flow. In PC12 cells, DDB could promote the separation of mTOR and lysosome, promote the nuclear translocation of transcription factor EB (TFEB), and then promote lysosome biogenesis and lysosome acidification by targeting ATP6V1A.
    CONCLUSION: These results unraveled that preventive administration of DNLA may delay the impairment of learning and memory in APP/PS1 mice. The molecular mechanism may be related to promoting the mTOR-TFEB-v-ATPase pathway.
    Keywords:  Alzheimer's disease; alkaloids from Dendrobium nobile Lindl; autophagic lysosomes; lysosomal biogenesis; v‐ATPase
    DOI:  https://doi.org/10.1111/cns.70300
  17. J Neuromuscul Dis. 2025 Mar 04. 22143602251314767
    Recent advances in the clinical spectrum and pathomechanisms associated with X-linked myopathy with excessive autophagy and other VMA21-related disorders.
    Ilaria Cocchiararo, Perrine Castets.
      X-linked myopathy with excessive autophagy (XMEA) is a rare neuromuscular disorder caused by mutations in the VMA21 gene, encoding a chaperone protein present in the endoplasmic reticulum (ER). In yeast and human, VMA21 has been shown to chaperone the assembly of the vacuolar (v)-ATPase proton pump required for the acidification of lysosomes and other organelles. In line with this, VMA21 deficiency in XMEA impairs autophagic degradation steps, which would be key in XMEA pathogenesis. Recent years have witnessed a surge of interest in VMA21, with the identification of novel mutations causing a congenital disorder of glycosylation (CDG) with liver affection, and its potent implication in cancer predisposition. With this, VMA21 deficiency has been further linked to defective glycosylation, lipid metabolism dysregulation and ER stress. Moreover, the identification of two VMA21 isoforms, namely VMA21-101 and VMA21-120, has opened novel avenues regarding the pathomechanisms leading to XMEA and VMA21-CDG. In this review, we discuss recent advances on the clinical spectrum associated with VMA21 deficiency and on the pathophysiological roles of VMA21.
    Keywords:  VMA21; X-linked myopathy with excessive autophagy; autophagic vacuolar myopathies
    DOI:  https://doi.org/10.1177/22143602251314767
  18. Autophagy. 2025 Mar 06.
    Cleavage of the selective autophagy receptor NBR1 by the PDCoV main protease NSP5 impairs autophagic degradation of the viral envelope protein.
    Ke Li, Dong Chen, Kangli Zhao, Dan Liu, Dongni Kong, Yu Sun, Aohan Guan, Peng Zhou, Hui Jin, Anan Jongkaewwattana, Sizhu Suolang, Dang Wang, Hongbo Zhou, Rui Luo.
      Porcine deltacoronavirus (PDCoV) is an emerging enteropathogenic coronavirus that causes severe diarrhea in neonatal piglets worldwide and presents a significant public health threat due to its potential for cross-species transmission. Selective macroautophagy/autophagy, mediated by autophagy receptors such as NBR1 (NBR1 autophagy cargo receptor), plays a key role in restricting viral infection and modulating the host immune response. In this study, we revealed that overexpression of NBR1 inhibits PDCoV replication, while its knockdown increases viral titers. Further analysis demonstrated that NBR1 interacts with the PDCoV envelope (E) protein independently of ubiquitination, directing it to phagophores for autophagic degradation to limit viral proliferation. To counteract this defense, PDCoV 3C-like protease, encoded by NSP5, cleaves porcine NBR1 at glutamine 353 (Q353), impairing its selective autophagy function and antiviral activity. Additionally, we demonstrated that NSP5 proteases from other coronaviruses including PEDV, TGEV, and SARS-CoV-2 also cleave NBR1 at the same site, suggesting that coronaviruses employ a conserved strategy of NSP5-mediated cleavage of NBR1 to evade host antiviral responses and facilitate infection. Overall, our study underscores the importance of NBR1-mediated selective autophagy in the host's defense against PDCoV and reveals a strategy by which PDCoV evades autophagic mechanisms to promote successful infection.
    Keywords:  Cleavage; NBR1; NSP5; PDCoV; selective autophagy
    DOI:  https://doi.org/10.1080/15548627.2025.2474576
  19. Traffic. 2025 Jan-Mar;26(1-3):26(1-3): e70000
    Adaptor-Mediated Trafficking of Tank Binding Kinase 1 During Diverse Cellular Processes.
    Swagatika Paul, Sahitya Ranjan Biswas, Julia P Milner, Porter L Tomsick, Alicia M Pickrell.
      The serine/threonine kinase, Tank Binding Kinase 1 (TBK1), drives distinct cellular processes like innate immune signaling, selective autophagy, and mitosis. It is suggested that the translocation and activation of TBK1 at different subcellular locations within the cell, downstream of diverse stimuli, are driven by TBK1 adaptor proteins forming a complex directly or indirectly with TBK1. Various TBK1 adaptors and associated proteins like NAP1, TANK, SINTBAD, p62, optineurin (OPTN), TAX1BP1, STING, and NDP52 have been identified in facilitating TBK1 activation and recruitment with varying overlapping redundancy. This review focuses on what is known about these proteins, their interactions with TBK1, and the functional consequences of these associations. We shed light on underexplored areas of research on these TBK1 binding partners while emphasizing how future research is required to understand the function and flexibility of TBK1 signaling and crosstalk or regulation between different biological processes.
    Keywords:  NAP1; NDP52; OPTN; SINTBAD; TANK; TAX1BP1; TBK1; autophagy; innate immunity; p62
    DOI:  https://doi.org/10.1111/tra.70000
  20. J Cell Biol. 2025 May 05. pii: e202404009. [Epub ahead of print]224(5):
    SNX10 functions as a modulator of piecemeal mitophagy and mitochondrial bioenergetics.
    Laura Trachsel-Moncho, Chiara Veroni, Benan John Mathai, Ana Lapao, Sakshi Singh, Nagham Theres Asp, Sebastian W Schultz, Serhiy Pankiv, Anne Simonsen.
      We here identify the endosomal protein SNX10 as a negative regulator of piecemeal mitophagy of OXPHOS machinery components. In control conditions, SNX10 localizes to early endocytic compartments in a PtdIns3P-dependent manner and modulates endosomal trafficking but also shows dynamic connections with mitochondria. Upon hypoxia-mimicking conditions, SNX10 localizes to late endosomal structures containing selected mitochondrial proteins, including COX-IV and SAMM50, and the autophagy proteins SQSTM1/p62 and LC3B. The turnover of COX-IV was enhanced in SNX10-depleted cells, with a corresponding reduced mitochondrial respiration and citrate synthase activity. Importantly, zebrafish larvae lacking Snx10 show reduced levels of Cox-IV, as well as elevated ROS levels and ROS-mediated cell death in the brain, demonstrating the in vivo relevance of SNX10-mediated modulation of mitochondrial bioenergetics.
    DOI:  https://doi.org/10.1083/jcb.202404009
  21. Br J Pharmacol. 2025 Mar 07.
    Clemastine attenuates subarachnoid haemorrhage pathology in a mouse model via Nrf2/SQSTM1-mediated autophagy.
    Yan Zou, Zhen'xing Tao, Peng'peng Li, Jie'qiong Yang, Qin'yi Xu, Xing Xu, Zeng'li Miao, Xu'dong Zhao.
       BACKGROUND AND PURPOSE: Subarachnoid haemorrhage (SAH) is an uncommon and severe subtype of stroke, but the availability of drugs for its treatment is limited. Enhanced autophagy is believed to attenuate SAH pathology; however, autophagy level is tentatively up-regulated and then down-regulated after SAH onset in mice. Clemastine, a first-generation histamine H1R antagonist, is believed to persistently enhance autophagy. However, the precise mechanism of clemastine in the treatment of SAH remains largely elusive.
    EXPERIMENTAL APPROACH: Haemoglobin-induced neuron injury model and autologous-blood-injected SAH-model mice were used to investigate the effects of clemastine in vitro and in vivo, respectively. The expressions of Nrf2/Keap1 and autophagy-related proteins were detected using western blotting and immunofluorescence. Neuronal injury and hyperoxide level were measured via Fluoro-Jade C and dihydroethidium staining. Neurological behaviours were evaluated using modified Garcia Scale, beam balance test, Morris water maze, Y-maze and novel object recognition test. The structures of autophagosomes and mitochondria were visualised using transmission electron microscope. The binding sites of clemastine was predicted and verified using database and drug affinity-responsive target stability.
    KEY RESULTS: Clemastine ameliorated SAH pathogenesis in vivo and in vitro. Moreover, the intraperitoneal injection of clemastine and its oral administration reduced neuronal death and improved cognitive deficits in SAH-model mice. Mechanistically, clemastine directly bound to muscarinic acetylcholine receptor M4, prevented Nrf2 degradation via Nrf2/Keap1/SQSTM1 pathway and promoted Nrf2 nuclear translocation, thus enhancing autophagy-related gene transcription and autophagy activation.
    CONCLUSIONS AND IMPLICATIONS: Clemastine can attenuate SAH pathology via the activation of Nrf2/SQSTM1 autophagy and could be a useful therapeutic in the context of SAH.
    Keywords:  CHRM4; Nrf2; SQSTM1; autophagy; clemastine; subarachnoid haemorrhage
    DOI:  https://doi.org/10.1111/bph.17465
  22. Apoptosis. 2025 Mar 05.
    Role of the USP family in autophagy regulation and cancer progression.
    Congcong Liu, Yalin Yuan, Yuxin Zhan, Mi Zou, Linqian Wu, Chunfang Zhang, Bofan Chen, Haimin Zeng, Ruhui Yang, Tianheng Hu, Jie Peng, Liang Hao.
      Autophagy is a vital pathway for recycling and degrading intracellular materials, closely linked to tumorigenesis and progression. The ubiquitin-specific protease (USP) family, as a critical group of deubiquitinating enzymes, plays a complex part in regulating autophagy, metabolism, immune responses, and tumor cells' resistance to drugs. By modifying autophagy-associated proteins through deubiquitination, the USP family influences tumor cell proliferation, survival, and metabolism. Additionally, these enzymes are involved in modulating immune responses within the tumor microenvironment, thereby impacting tumor immune escape. Regarding drug resistance, the USP family enhances the tolerance of tumor cells to chemotherapeutic agents by promoting autophagy. Therefore, targeting USP family members and their regulated autophagy processes may offer new avenues for cancer therapy. This review examines the function of the USP family in tumor autophagy regulation and its implications for tumor progression. The goal of future studies should be to clarify the molecular mechanisms underlying USP-autophagy interactions and their specific roles in various tumor types to establish a theoretical framework for developing novel cancer therapeutic strategies.
    Keywords:  Autophagy; Deubiquitination; Tumor; Ubiquitin-specific proteases (USPs)
    DOI:  https://doi.org/10.1007/s10495-025-02095-z
  23. Antiviral Res. 2025 Feb 26. pii: S0166-3542(25)00050-6. [Epub ahead of print]237 106124
    Apatinib inhibits HTNV by stimulating TFEB-driven lysosome biogenesis to degrade viral protein.
    Qikang Ying, Xiaoxiao Zhang, Tianle Gu, Junmei Zhang, Yuhang Dong, Wenjie Feng, Dongjing Li, Xingan Wu, Fang Wang.
      Hantaan Orthohantavirus (Hantaan virus, HTNV) infection causes hemorrhagic fever with renal syndrome (HFRS) in humans, posing a significant health threat. Currently, there are no long-lasting protective vaccines or specific antivirals available, creating an urgent need for effective antiviral treatments in the clinical management of HFRS. Given that viruses exploit multiple host factors for their replication, host-oriented inhibitors could offer promising therapeutic options. In our study, we screened a library of 2570 drugs and identified apatinib, a kinase inhibitor, as a potent suppressor of HTNV infection both in vitro and in vivo. Mechanistic studies revealed that apatinib exerts its antiviral effect by targeting transcription factor EB (TFEB). Specifically, apatinib inhibits the PI3K-Akt signaling pathway and reduces mTOR phosphorylation, which in turn downregulates TFEB phosphorylation. This facilitates the nuclear translocation of TFEB and enhances lysosomal function by upregulating the expression of lysosome-associated genes and promoting lysosome biogenesis. Consequently, there is an increase in lysosome-mediated viral nucleocapsid protein degradation. The ability of apatinib to stimulate this lysosome-driven antiviral mechanism presents a potential new therapeutic approach for viral infections and offers valuable insights into virus-host interactions during HTNV replication.
    Keywords:  Drug repurpose; Hantaan virus (HTNV); Transcription factor EB (TFEB); Vascular endothelial growth factor receptor-2 (VEGFR2)
    DOI:  https://doi.org/10.1016/j.antiviral.2025.106124
  24. Acta Pharmacol Sin. 2025 Mar 03.
    Intracerebellar upregulation of Rheb(S16H) ameliorates motor dysfunction in mice with SCA2.
    Sehwan Kim, Junwoo Park, Hyemi Eo, Gi Beom Lee, Se Min Park, Minsang Shin, Seung Eun Lee, Youngpyo Nam, Sang Ryong Kim.
      Cerebellar ataxia (CA) is characterized by impaired balance and coordination due to the loss of cerebellar neurons caused by various factors, and effective treatments are currently lacking. Recently, we observed reduced expression of signaling molecules in the mammalian target of rapamycin complex 1 (mTORC1) pathway in the cerebellum of mice with spinocerebellar ataxia type 2 (SCA2) compared with wild-type mice. To investigate the effects of mTORC1 upregulation on motor dysfunction in mice with SCA2, we administered an intracerebellar injection of adeno-associated virus serotype 1 carrying a constitutively active form of Ras homolog enriched in brain [Rheb(S16H)], which is an upstream activator of mTORC1. This treatment led to increased Rheb(S16H) expression in calbindin-D28K-positive Purkinje cells and increased levels of neurotrophic factors. Additionally, Rheb(S16H) upregulation reduced abnormal behaviors and protected Purkinje cells in mice with SCA2. Our findings suggest that upregulating Rheb(S16H) in the cerebellum may be a promising therapeutic strategy for hereditary CA.
    Keywords:  AAV1-Rheb(S16H); cerebellar ataxia; mTORC1; motor dysfunction; neuroprotection; neurotrophic factor
    DOI:  https://doi.org/10.1038/s41401-025-01504-y
  25. Acta Physiol (Oxf). 2025 Apr;241(4): e70012
    Trophoblast-specific Deptor knockdown enhances trophoblast nutrient transport and fetal growth in mice.
    Lance G A Nunes, Rodrigo B Weingrill, Sam Blessen J Fredrick, Ramon Lorca, Men-Jean Lee, Shaikh M Atif, Adam J Chicco, Fredrick J Rosario, Johann Urschitz.
       AIM: Silencing of DEP-domain containing mTOR-interacting protein (DEPTOR), an endogenous inhibitor of the mammalian target of rapamycin (mTOR) pathway, increases mTOR signaling and System A/L amino acid transport activity in cultured primary human trophoblast cells. However, there is no evidence supporting the regulatory role of DEPTOR signaling in placental function in vivo. We hypothesized that trophoblast-specific Deptor knockdown (KD) in mice increases trophoblast mTOR signaling, amino acid transport, and enhances fetal growth.
    METHODS: We generated trophoblast-specific DeptorKD transgenic mice, and at embryonic day 18.5, placentas were analyzed to confirm knockdown efficiency, specificity, and mTOR signaling pathway levels. Trophoblast plasma membrane (TPM) System A/L amino acid transport expression and activity were also determined. We also examined the relationship between birthweight and DEPTOR protein levels in human placentas collected at term from appropriate for gestational age (AGA) and large for gestational age (LGA) pregnancies.
    RESULTS: Reducing trophoblast Deptor RNA levels increased placental mTOR signaling, System A/L transporter expression/activity, and fetal growth in mice. Similarly, human LGA placentas displayed decreased DEPTOR protein levels, inversely correlated to birthweight and BMI.
    CONCLUSIONS: This is the first report showing that trophoblast-specific DeptorKD is sufficient to activate mTOR signaling, a master regulator of placental function, which increases the TPM System A and L amino acid transporter expression and activity. We also propose that Deptor expression is mechanistically linked to placental mTOR signaling and fetal growth. Furthermore, modulation of DEPTOR signaling may represent a promising approach to improve outcomes in pregnancies characterized by abnormal fetal growth.
    Keywords:  fetal development; maternal‐fetal exchange; mechanistic target of rapamycin; placenta; transposase‐enhanced pronuclear injection
    DOI:  https://doi.org/10.1111/apha.70012
  26. Adv Sci (Weinh). 2025 Mar 07. e2411662
    Coordinated Role of Autophagy and ERAD in Maintaining Neuroendocrine Function by Preventing Prohormone Aggregation.
    Xuya Pan, Xing He, Su Wu, Na Xiong, Xinyu Hou, Heting Wang, Diane Somlo, Martin Spiess, Haiyang Wang, Jifeng Yang, Chunliang Li, Shasha Li, Wenbin Ma, Yanming Chen, Jun Cui, Ling Qi, Guojun Shi.
      Proteotoxicity induced by misfolded or aggregated proteins causes progressive neuronal damage. The endoplasmic reticulum (ER) protein quality control (ERQC) pathways are responsible for mitigating the accumulation of these misfolded or aggregated proteins, thus reducing proteotoxicity. Enhancing ERQC pathways is a promising strategy for treating neurodegenerative diseases. However, the mechanisms governing the initiation and degradation of misfolded or aggregated proteins in neurons remain largely unknown in vivo. In studying the maturation of proAVP in mouse AVP neurons, this study discovers that autophagy and ER-associated degradation (ERAD) ERQC pathways collaborate to maintain proAVP maturation and protect AVP neuron survival against proteotoxicity. Autophagy deficiency in mouse AVP neurons leads to the late-onset of diabetes insipidus. Mechanistically, autophagy selectively degrades mutant proAVP aggregates and endogenous HRD1 of the SEL1L-HRD1 ERAD complex through FAM134B mediated ER-phagy. HRD1 induction is responsible for reducing proAVP aggregation and maintaining AVP neuron function and survival under autophagy deficiency. Thus, autophagy and ERAD form a dual-protection system that orchestrates prohormone maturation and endocrine neuron survival, providing new insights in the complexity of neuroendocrinology and the intrinsic mechanism of neurodegenerative diseases, with therapeutic potential in protein folding diseases.
    Keywords:  ERAD; autophagy; diabetes insipidus; endocrine neurons; protein aggregates
    DOI:  https://doi.org/10.1002/advs.202411662
  27. J Biol Chem. 2025 Mar 04. pii: S0021-9258(25)00233-9. [Epub ahead of print] 108384
    Double Prenylation of Budding Yeast Ykt6 Regulates Cell Wall Integrity and Autophagy.
    Masaki Tateishi, Kota Goto, Eiji Hishinuma, Naomi Matsukawa, Takuma Kishimoto, Kazuma Tanaka, Hisanori Horiuchi, Masayoshi Fukasawa, Ryutaro Shirakawa.
      Ykt6 is a conserved SNARE protein involved in multiple membrane trafficking pathways, including intra-Golgi transport and autophagic membrane fusion. We previously demonstrated that mammalian Ykt6 is uniquely modified with farnesyl and geranylgeranyl groups at two C-terminal cysteines through the sequential action of farnesyltransferase (FT) and geranylgeranyltransferase type 3 (GGT3). Although these two cysteines are strictly conserved in all eukaryotes, the evolutionary conservation of Ykt6 double prenylation remains unclear, as budding yeast appears to lack the α subunit of GGT3. In this study, we used structural predictions to identify the uncharacterized protein Ecm9 as the functional α subunit of yeast GGT3. Ecm9 forms a complex with Bet2 and transfers a geranylgeranyl group to mono-farnesylated Ykt6. MALDI-TOF/TOF mass spectrometry confirmed that budding yeast Ykt6 is doubly prenylated with farnesyl and geranylgeranyl groups in wild-type cells but not in ecm9Δ cells. Loss of Ecm9 resulted in fragile cell walls, likely due to mislocalization of Golgi mannosyltransferases. Furthermore, ecm9Δ cells exhibited impaired Ykt6 localization to organelle membranes including autophagosomes, leading to reduced autophagic activity. These findings establish that double prenylation is an evolutionarily conserved structural feature of Ykt6 and is essential for its membrane localization and function.
    Keywords:  MALDI-TOF/TOF; SNARE proteins; Ykt6; autophagy; cell wall; glycosyltransferase; membrane trafficking; organelle proteome; protein isoprenylation; protein prenyltransferase
    DOI:  https://doi.org/10.1016/j.jbc.2025.108384
  28. Neurosci Res. 2025 Feb 27. pii: S0168-0102(25)00049-5. [Epub ahead of print]
    Metformin alleviates auditory cell senescence by mitophagy induction.
    Sung Il Cho, Eu-Ri Jo, Hee Sun Jang.
      Age-related hearing loss is the most common type of hearing loss in older adults. However, its underlying cellular mechanism is still unclear. Impaired mitochondrial function is a hallmark of various age-related pathologies. To maintain mitochondrial function in senescent cells, mitophagy is a crucial process for dysfunctional mitochondria turnover. Metformin has been reported to induce mitophagy. This study aimed to investigate the effect of metformin on preventing senescence in auditory cells. Low-dose H2O2 represented senescence-associated secretory phenotype (SASP) and reduced mitophagy-related molecules in House Ear Institute-Organ of Corti 1 (HEI-OC1) cells and cochlear explants. Metformin significantly decreased the expression of SASP in H2O2-induced senescent cells. Metformin also decreased the expression of senescence-associated p53 and p21, and increased the expression of mitophagy-related PINK1, Parkin, and BNIP3 in H2O2-induced senescent cells and cochlear explants. The co-localization of mitophagy dye and lyso dye decreased in H2O2-induced senescent cells, but metformin pre-treatment significantly increased their colocalization. Metformin significantly decreased the percentage of β-galactosidase-stained senescent cells and increased the expression of OXPHOS complexes in H2O2-induced senescent cells and cochlear explants. Metformin also significantly increased mitochondrial function in senescent cells. These results indicate that metformin prevented premature senescence in auditory cells by counteracting reduced mitophagy. Therefore, maintaining mitochondrial function using metformin might be a potential strategy for the prevention of age-related hearing loss.
    Keywords:  Metformin; Mitochondria; Mitophagy; Senescence
    DOI:  https://doi.org/10.1016/j.neures.2025.02.008
  29. Sci Adv. 2025 Feb 28. 11(9): eadr1938
    A long-lived pool of PINK1 imparts a molecular memory of depolarization-induced activity.
    Liam Pollock, Ioanna Ch Georgiou, Emma V Rusilowicz-Jones, Michael J Clague, Sylvie Urbé.
      The Parkinson's disease-linked kinase, PINK1, is a short-lived protein that undergoes cleavage upon mitochondrial import leading to its proteasomal degradation. Under depolarizing conditions, it accumulates on mitochondria where it becomes activated, phosphorylating both ubiquitin and the ubiquitin E3 ligase Parkin, at Ser65. Our experiments reveal that in retinal pigment epithelial cells, only a fraction of PINK1 becomes stabilized after depolarization by electron transport chain inhibitors. Furthermore, the observed accrual of PINK1 cannot be completely accounted for without an accompanying increase in biosynthesis. We have used a ubiquitylation inhibitor TAK-243 to accumulate cleaved PINK1. Under these conditions, generation of unconjugated "free" phospho-ubiquitin serves as a proxy readout for PINK1 activity. This has enabled us to find a preconditioning phenomenon, whereby an initial depolarizing treatment leaves a residual pool of active PINK1 that remains competent to seed the activation of nascent cleaved PINK1 following a 16-hour recovery period.
    DOI:  https://doi.org/10.1126/sciadv.adr1938
  30. EMBO Rep. 2025 Mar 03.
    Caspase cleavage of influenza A virus M2 disrupts M2-LC3 interaction and regulates virion production.
    Carmen Figueras-Novoa, Masato Akutsu, Daichi Murata, Anne Weston, Ming Jiang, Beatriz Montaner, Christelle Dubois, Avinash Shenoy, Rupert Beale.
      Influenza A virus (IAV) Matrix 2 protein (M2) is an ion channel, required for efficient viral entry and egress. M2 interacts with the small ubiquitin-like LC3 protein through a cytoplasmic C-terminal LC3-interacting region (LIR). Here, we report that M2 is cleaved by caspases, abolishing the M2-LC3 interaction. A crystal structure of the M2 LIR in complex with LC3 indicates the caspase cleavage tetrapeptide motif (82SAVD85) is an unstructured linear motif that does not overlap with the LIR. IAV mutant expressing a permanently truncated M2, mimicking caspase cleavage, exhibit defects in M2 plasma membrane transport, viral filament formation, and virion production. Our results reveal a dynamic regulation of the M2-LC3 interaction by caspases. This highlights the role of host proteases in regulating IAV exit, relating virion production with host cell state.
    Keywords:  Autophagy; Caspase; Influenza; LC3; M2
    DOI:  https://doi.org/10.1038/s44319-025-00388-7
  31. bioRxiv. 2025 Feb 20. pii: 2025.02.19.639160. [Epub ahead of print]
    Novel reporter of the PINK1-Parkin mitophagy pathway identifies its damage sensor in the import gate.
    Julia A Thayer, Jennifer D Petersen, Xiaoping Huang, James Hawrot, Daniel M Ramos, Shiori Sekine, Yan Li, Michael E Ward, Derek P Narendra.
      Damaged mitochondria can be cleared from the cell by mitophagy, using a pathway formed by the recessive Parkinson's disease genes PINK1 and Parkin. How mitochondrial damage is sensed by the PINK1-Parkin pathway, however, remains uncertain. Here, using a Parkin substrate-based reporter in genome-wide screens, we identified that diverse forms of mitochondrial damage converge on loss of mitochondrial membrane potential (MMP) to activate PINK1. Consistently, the MMP but not the presequence translocase-associated motor (PAM) import motor provided the essential driving force for endogenous PINK1 import through the inner membrane translocase TIM23. In the absence of TIM23, PINK1 arrested in the translocase of the outer membrane (TOM) during import. The energy-state outside of the mitochondria further modulated the pathway by controlling the rate of new PINK1 synthesis. Our results identify separation of PINK1 from TOM by the MMP, as the key damage-sensing switch in the PINK1-Parkin mitophagy pathway.
    Highlights: MFN2-Halo is a quantitative single-cell reporter of PINK1-Parkin activation.Diverse forms of mitochondrial damage, identified in whole-genome screens, activate the PINK1-Parkin pathway by disrupting the mitochondrial membrane potential (MMP).The primary driving force for endogenous PINK1 import through the TIM23 translocase is the MMP with the PAM import motor playing a supporting role.Loss of TIM23 is sufficient to stabilize PINK1 in the TOM complex and activate Parkin.
    DOI:  https://doi.org/10.1101/2025.02.19.639160
  32. Neurobiol Dis. 2025 Mar 04. pii: S0969-9961(25)00078-6. [Epub ahead of print] 106862
    Mitochondria at the crossroads: Quality control mechanisms in neuronal senescence and neurodegeneration.
    Yifei Zheng, Jiahui Yang, Xuanyao Li, Linjie Qi, Zhuo Zheng, Jiming Kong, Guohui Zhang, Ying Guo.
      Mitochondria play a central role in essential cellular processes, including energy metabolism, biosynthesis of metabolic substances, calcium ion storage, and regulation of cell death. Maintaining mitochondrial quality control is critical for preserving mitochondrial health and ensuring cellular function. Given their high energy demands, neurons depend on effective mitochondrial quality control to sustain their health and functionality. Neuronal senescence, characterized by a progressive decline in structural integrity and function, is a hallmark of neurodegenerative diseases. In senescent neurons, abnormal mitochondrial morphology, functional impairments, increased reactive oxygen species production and disrupted quality control mechanisms are frequently observed. Understanding the pathological changes in neuronal structure, exploring the intricate relationship between mitochondrial quality control and neuronal health, and leveraging mitochondrial quality control interventions provide a promising foundation for addressing age-related neurodegenerative diseases. This review highlights key mitochondrial quality control, including biogenesis, dynamics, the ubiquitin-proteasome system, autophagy pathways, mitochondria-derived vesicles, and inter-organelle communication, while discussing their roles in neuronal senescence and potential therapeutic strategies. These insights may pave the way for innovative treatments to mitigate neurodegenerative disorders.
    Keywords:  Mitochondrial quality control; Neurodegenerative diseases; Neuron; Senescence; Therapeutic strategies
    DOI:  https://doi.org/10.1016/j.nbd.2025.106862
  33. Cell Stress Chaperones. 2025 Feb 27. pii: S1355-8145(25)00011-2. [Epub ahead of print]
    CHOP aggravates hepatocyte apoptosis upon endoplasmic reticulum stress by down-regulating autophagy.
    Jia-Yu Wu, Bing Han, Ting Yang, Lu Zheng, Yi-Xin Guo, Jia-Yao Li, Xiao-Yu Guo, Huan-Huan Yin, Ru-Jia Xie.
       BACKGROUND: Endoplasmic reticulum (ER) stress-associated apoptosis is involved in various liver diseases, including liver fibrosis, nonalcoholic fatty liver disease, and cirrhosis. Hepatocytes respond to ER stress by eliciting unfolded protein response (UPR) and enhancing autophagy. Autophagy is a pivotal mechanism for sustaining normal ER function, through degradation of damaged ER fragments and removal of abnormal protein aggregates in the ER lumen. Failure to restore ER homeostasis via autophagy is harmful to hepatocytes and contributes to ER stress-associated apoptosis. Recent findings indicated that C/EBP homologous protein (CHOP) could exacerbate ER stress-related apoptosis by down-regulating autophagy, but the underlying mechanism remains elusive.
    AIM: To investigate the impact of CHOP on ER stress-induced apoptosis in rat hepatocytes, and the potential molecular mechanisms.
    METHODS: BRL-3A cells were pre-treated with rapamycin (RAP) and 3-methyladenine, then treated with dithiothreitol (DTT). Growth and apoptotic rates were detected using real-time cellular analysis (RTCA) and flow cytometry, respectively. ER stress-associated molecule levels were determined via western blotting. CHOP, small interfering RNA, and the lentivirus vector system were used to transfect BRL-3A cells and observe the impact of CHOP gene silencing or overexpression on autophagy and apoptosis. Chromatin immunoprecipitation (ChIP) was used to confirm whether CHOP binds directly to ATG12, ATG5, and LC3 promotor regions undergoing ER stress.
    RESULTS: ER stress-associated molecules were dramatically upregulated in BRL-3A hepatocytes and hepatocyte apoptosis was augmented. RAP pre-treatment significantly reduced DTT-induced expression of ER stress-associated molecules; conversely, 3-MA pre-treatment promoted DTT-induced levels of ER stress-associated apoptotic molecules. Following the decreased CHOP expression in hepatocytes, the level of autophagy-associated molecules dramatically increased, and DTT-induced hepatocyte apoptosis decreased. However, opposite trends were observed in CHOP overexpression cells. A negative regulation of CHOP on autophagy-associated molecules including ATG12, ATG5, and LC3 in BRL-3A cells upon DTT treatment was detected via ChIP.
    CONCLUSION: CHOP enhancement during ER stress inhibits autophagy and promotes hepatocyte apoptosis; however, the decreased CHOP gene expression could attenuate DTT-induced hepatocyte apoptosis. Overexpression of CHOP could aggravate DTT-induced hepatocyte apoptosis.
    Keywords:  Apoptosis; Autophagy; C/EBP homologous protein; Endoplasmic reticulum stress; Hepatocyte
    DOI:  https://doi.org/10.1016/j.cstres.2025.02.005
  34. Bone Res. 2025 Mar 03. 13(1): 30
    Enhanced SIRT3 expression restores mitochondrial quality control mechanism to reverse osteogenic impairment in type 2 diabetes mellitus.
    Yansi Xian, Bin Liu, Tao Shen, Lin Yang, Rui Peng, Hongdou Shen, Xueying An, Yutian Wang, Yu Ben, Qing Jiang, Baosheng Guo.
      Osteoporosis represents a prevalent and debilitating comorbidity in patients diagnosed with type 2 diabetes mellitus (T2DM), which is characterized by suppressed osteoblast function and disrupted bone microarchitecture. In this study, we utilized male C57BL/6 J mice to investigate the role of SIRT3 in T2DM. Decreased SIRT3 expression and impaired mitochondrial quality control mechanism are observed in both in vitro and in vivo models of T2DM. Mechanistically, SIRT3 suppression results in hyperacetylation of FOXO3, hindering the activation of the PINK1/PRKN mediated mitophagy pathway and resulting in accumulation of dysfunctional mitochondria. Genetical overexpression or pharmacological activation of SIRT3 restores deacetylation status of FOXO3, thus facilitating mitophagy and ameliorating osteogenic impairment in T2DM. Collectively, our findings highlight the fundamental regulatory function of SIRT3 in mitochondrial quality control, crucial for maintaining bone homeostasis in T2DM. These insights not only enhance our understanding of the molecular mechanisms underlying diabetic osteoporosis but also identify SIRT3 as a promising therapeutic target for diabetic osteoporosis.
    DOI:  https://doi.org/10.1038/s41413-024-00399-5
  35. Mitochondrion. 2025 Mar 03. pii: S1567-7249(25)00021-2. [Epub ahead of print] 102024
    The compound XueShuanTong promotes podocyte mitochondrial autophagy via the AMPK/mTOR pathway to alleviate diabetic nephropathy injury.
    Chuangbiao Zhang, Weiwei Ren, Xiaohua Lu, Lie Feng, Jiaying Li, Beibei Zhu.
      The study aimed to elucidate the molecular mechanisms underlying the protective effects of Compound Xueshuantong (CXst) in the context of diabetic nephropathy (DN), a major cause of kidney failure driven by podocyte injury and metabolic dysfunction. Given the critical role of the AMPK/mTOR signaling pathway in regulating cellular energy balance, autophagy, and mitochondrial health, we focused on its involvement in podocyte function and how it might be influenced by CXst. Through a series of experiments, we found that CXst treatment led to the upregulation of key proteins involved in autophagy, such as LC3 and p62, as well as proteins critical for mitochondrial function, like PGC-1α. These molecular changes helped to counteract the damaging effects of high glucose levels on podocytes, which are central to maintaining the filtration function of the kidneys. Additionally, CXst's ability to modulate the AMPK/mTOR pathway was shown to be a pivotal factor in its protective effects, as inhibition of AMPK significantly reduced these benefits. This comprehensive study provides strong evidence that CXst exerts its protective effects against DN by modulating the AMPK/mTOR pathway, thus preserving podocyte integrity and function. These findings suggest that CXst could be a promising candidate for the development of new therapeutic strategies for the treatment of DN, offering hope for better management of this challenging condition.
    Keywords:  Adenylate activated protein kinase/mammalian target of rapamycin signaling pathway; Compound Xueshuantong; Diabetic nephropathy; Mitochondrial autophagy; Nephrin; Podocin
    DOI:  https://doi.org/10.1016/j.mito.2025.102024
  36. Adv Sci (Weinh). 2025 Mar 07. e2416598
    MTCH2 Suppresses Thermogenesis by Regulating Autophagy in Adipose Tissue.
    Xin-Yuan Zhao, Ben-Chi Zhao, Hui-Lin Li, Ying Liu, Bei Wang, An-Qi Li, Tian-Shu Zeng, Hannah Xiaoyan Hui, Jia Sun, Domagoj Cikes, Nele Gheldof, Jorg Hager, Jian-Xun Mi, D Ross Laybutt, Yin-Yue Deng, Yan-Chuan Shi, G Gregory Neely, Qiao-Ping Wang.
      Stimulating adipose tissue thermogenesis has emerged as a promising strategy for combating obesity, with uncoupling protein 1 (UCP1) playing a central role in this process. However, the mechanisms that suppress adipose thermogenesis and energy dissipation in obesity are not fully understood. This study identifies mitochondrial carrier homolog 2 (MTCH2), an obesity susceptibility gene, as a negative regulator of energy homeostasis across flies, rodents, and humans. Notably, adipose-specific MTCH2 depletion in mice protects against high-fat-diet (HFD)-induced obesity and metabolic disorders. Mechanistically, MTCH2 deficiency promotes energy expenditure by stimulating thermogenesis in brown adipose tissue (BAT) and browning of subcutaneous white adipose tissue (scWAT), accompanied by upregulated UCP1 protein expression, enhanced mitochondrial biogenesis, and increased lipolysis in BAT and scWAT. Using integrated RNA sequencing and proteomic analyses, this study demonstrates that MTCH2 is a key suppressor of thermogenesis by negatively regulating autophagy via Bcl-2-dependent mechanism. These findings highlight MTCH2's critical role in energy homeostasis and reveal a previously unrecognized link between MTCH2, thermogenesis, and autophagy in adipose tissue biology, positioning MTCH2 as a promising therapeutic target for obesity and related metabolic disorders. This study provides new opportunities to develop treatments that enhance energy expenditure.
    Keywords:  adipose tissue; autophagy; mitochondrial carrier homolog 2 (MTCH2); obesity; thermogenesis
    DOI:  https://doi.org/10.1002/advs.202416598
  37. Oncogene. 2025 Mar 01.
    PPDPF-mediated regulation of BCAA metabolism enhances mTORC1 activity and drives cholangiocarcinoma progression.
    Zhi Li, Yidi Guan, Jie Gao, Lan Zhu, Zimei Zeng, Qianyu Jing, Quan Wan, Qi Fan, Xinxin Ren, Haiping Pei, Dexiang Zhang, Yefei Rong, Zhuoxian Rong, Junju He, Yuefang Zhang, Nan Li, Pan Chen, Lunquan Sun, Bin Xu, Yingjie Nie, Yuezhen Deng.
      Tumor cells display profound changes in the metabolism of branched-chain amino acids (BCAA). However, how these changes are regulated to facilitate tumorigenesis is not yet completely understood. Here, we identified pancreatic progenitor cell differentiation and proliferation factor (PPDPF) as a BCAA-responsive protein through extensive screening using stable isotope labeling with amino acids in cell culture (SILAC). PPDPF is upregulated in cholangiocarcinoma to enhance the malignant phenotype of cholangiocarcinoma cells by activating the mTORC1 signaling pathway. Metabolic flux analysis and mechanistic studies revealed that PPDPF prevented the interaction between MCCA and MCCB, thus inhibiting leucine catabolism and activating mTORC1 signaling. Moreover, upon amino acid starvation, ariadne RBR E3 ubiquitin protein ligase 2 (ARIH2) and OTU deubiquitinase 4 (OTUD4) cooperatively regulated the stability of the PPDPF protein by modulating its ubiquitination. Additionally, monocytes/macrophage-derived IL-10 increased the BCAA content in cholangiocarcinoma cells and stabilized the PPDPF protein, even under amino acid starvation conditions. Knockout of PPDPF or restriction of leucine intake significantly inhibits the progression of cholangiocarcinoma in a mouse model. Collectively, we discovered a novel role for PPDPF in promoting the progression of cholangiocarcinoma by activating mTORC1 signaling through the inhibition of leucine catabolism. The present study suggests that targeting PPDPF or decreasing dietary leucine intake may provide a new strategy to improve the treatment efficacy of cholangiocarcinoma.
    DOI:  https://doi.org/10.1038/s41388-025-03320-4
  38. Sci Rep. 2025 Mar 04. 15(1): 7639
    miR-21 regulates autophagy and apoptosis of ectopic endometrial stromal cells of adenomyosis via PI3K/ AKT/ mTOR pathway.
    Jin-Jin Jia, Hui-Jie Lai, Bo-Wen Sun, Jie Lu, Yu-Yan Zeng.
      Adenomyosis (AM) is a common and challenging disease in gynecological clinics, which adversely affects women's physical and mental health. Despite the growing number of studies, the mechanisms associated with the growth of the lesion are poorly understood. Studies show that abnormal proliferation, apoptosis, and migration in ectopic endometrial stromal cells (EESc) of AM may contribute to the development and progression of AM. Understanding the underlying molecular mechanisms can significantly contribute to diagnosing and treating AM. In the present study, EESc was isolated and cultured from the ectopic endometrium of patients with AM. These cells were treated with a PI3K/AKT activator (740 Y-P) and an inhibitor (LY294002), while the expression of microRNA-21 (miR-21) was interfered with. The effects of miR-21 on the apoptosis and autophagy of EESc, as well as the associated mechanisms, were investigated from multiple perspectives. Here, we found that 740 Y-P could significantly promote proliferation, inhibit apoptosis of EESc, and increase the expression of mTOR and p-mTOR proteins in EESc. Moreover, activating miR-21 enhanced the pro-migration effect of 740 Y-P and reversed the pro-apoptotic effect of LY294002, reducing the apoptosis rate and increasing the migration ability of EESc. Our investigation revealed that miR-21 can inhibit apoptosis and autophagy and promote migration of EESc. This effect is likely mediated via the PI3K/AKT/mTOR pathway.
    Keywords:  Adenomyosis; Apoptosis; Autophagy; Ectopic endometrial stromal cells; PI3K/ AKT/ mTOR pathway; microRNA-21 (miR-21)
    DOI:  https://doi.org/10.1038/s41598-025-92526-3
  39. Anim Biosci. 2025 Feb 27.
    Leucyl-tRNA Synthetase Regulates Casein Synthesis in Dairy Cows via the mTORC1-LAT1 Pathway.
    Yongding Ke, Ximeng Du, Binglan Chen, Xi Chen, Chengchuang Song, Xingtang Fang, Yanhong Wang, Chunlei Zhang.
       Objective: Leucyl-tRNA synthetase (LARS) is an essential multifunctional enzyme in mammals, pivotal in maintaining cellular protein and amino acid equilibrium. It facilitates tRNA aminoacylation, initiating intracellular protein synthesis, and serves as an intracellular leucine sensor. This sensor function enables LARS to activate the mTORC1 pathway via Rag GTPase binding, playing a critical role in protein synthesis regulation. Despite its significance, the precise mechanisms of these functions are yet to be fully delineated. This study focuses on LARS, specifically its role in modulating milk protein synthesis.
    Methods: In this study,the bovine mammary epithelial cells were selected as the research subject, and stable LARS-OE and LARS-KD cell lines were constructed, which were verified by Cell Counting Kit-8, Click-iT EdU , Western blot, RT-qPCR, and immunoconfocal techniques.
    Results: Our findings show that LARS overexpression in bovine mammary epithelial cells (MAC-T) not only enhances cell proliferation but also mediates intracellular leucine levels, thereby increasing casein production through the mTORC1 pathway. LARS further boosts casein expression via the mTORC1-LAT1(mechanistic Target of Rapamycin Complex 1, L-type Amino Transporters 1) pathway. Remarkably, this interaction is supported by a positive feedback mechanism from LAT1, enhancing the activation of the mTORC1 pathway. Additionally, LARS overexpression leads to increased LAT1 expression, improved LAT1 stability, and its augmented localization at the membrane. Our research indicates that LARS's enhancement of LAT1 expression is contingent on its dual roles in translation and leucine sensing, whereas its impact on LAT1 localization is exclusively dependent on its leucine sensing function.
    Conclusion: s: In summary, by detecting intracellular leucine levels, LARS regulates LAT1 expression and membrane positioning through the mTORC1 pathway, ultimately influencing casein synthesis. These insights lay a theoretical groundwork for advancing milk protein production and offer novel strategies for improving dairy product quality.
    Keywords:  LARS; LAT1; Leucine; mTORC1
    DOI:  https://doi.org/10.5713/ab.24.0711
  40. Ageing Res Rev. 2025 Feb 27. pii: S1568-1637(25)00059-5. [Epub ahead of print] 102713
    Mitochondrial Dysfunction in Alzheimer's Disease.
    Maria Clara Bila D'alessandro, Salim Kanaan, Mauro Geller, Domenico Praticò, João Paulo Lima Daher.
      Alzheimer's disease (AD) is a chronic neurodegenerative disease characterized by progressive cognitive decline and distinct neuropathological features. The absence of a definitive cure presents a significant challenge in neurology and neuroscience. Early clinical manifestations, such as memory retrieval deficits and apathy, underscore the need for a deeper understanding of the disease's underlying mechanisms. While amyloid-β plaques and tau neurofibrillary tangles have dominated research efforts, accumulating evidence highlights mitochondrial dysfunction as a central factor in AD pathogenesis. Mitochondria, essential cellular organelles responsible for energy production necessary for neuronal function become impaired in AD, triggering several cellular consequences. Factors such as oxidative stress, disturbances in energy metabolism, failures in the mitochondrial quality control system, and dysregulation of calcium release are associated with mitochondrial dysfunction. These abnormalities are closely linked to the neurodegenerative processes driving AD development and progression. This review explores the intricate relationship between mitochondrial dysfunction and AD pathogenesis, emphasizing its role in disease onset and progression, while also considering its potential as a biomarker and a therapeutic target.
    Keywords:  Mitochondrial dysfunction. Alzheimer’ disease. Pathology. Mitophagy. Neurodegeneration
    DOI:  https://doi.org/10.1016/j.arr.2025.102713
  41. FASEB J. 2025 Mar 15. 39(5): e70446
    Compression force regulates cementoblast mineralization via S1PR1/mitophagy axis.
    Han Wang, Jingwen Cai, Linxin Chen, Sihang Chen, Xinhan Yang, Zhonghan Chen, Linyu Xu.
      Orthodontically induced inflammatory root resorption (OIIRR) poses a significant clinical challenge, as excessive orthodontic force shortens tooth longevity by impairing cementoblast-mediated cementum mineralization and promoting root resorption. Cementoblasts, essential for mineralized cementum formation and resistance to resorption, exhibit altered mechanosensitivity and mechanotransduction under orthodontic force, yet the role of mitophagy in this process remains poorly understood. In this study, we investigated how the S1PR1/mitophagy axis modulates cementoblast mineralization and OIIRR progression. The in vivo orthodontic loading model revealed that heavy compression force triggered OIIRR and impaired cementoblast mineralization along with suppression of mitophagy in cementoblasts by downregulating PINK1 and PARKIN expression. The in vitro experiments further confirmed that heavy compression force increased reactive oxygen species (ROS) levels, disrupted mitochondrial membrane potential (MMP), and inhibited mitophagy in OCCM30 cells, thereby impairing their mineralization capacity. Mechanistically, S1PR1 upregulation activated mitophagy, which in turn restored cementoblast mineralization under heavy compression force. Moreover, pharmacological activation of S1PR1 with SEW2871 alleviated OIIRR in vivo. These findings highlight the pivotal role of the S1PR1/mitophagy axis in maintaining cementoblast function and mineralization under orthodontic force, offering novel insights into the molecular mechanisms underlying OIIRR and suggesting potential therapeutic strategies to prevent OIIRR during orthodontic treatment.
    Keywords:  S1PR1; cementoblast; mitophagy; orthodontic force; root resorption
    DOI:  https://doi.org/10.1096/fj.202403234RR
  42. J Biochem. 2025 Mar 04. pii: mvaf011. [Epub ahead of print]
    Innate immune responses to lysosomal nucleic acid stress.
    Kensuke Miyake, Takuma Shibata, Ryota Sato, Ryutaro Fukui.
      Nucleic acids (NAs) are recognized by endosomal Toll-like receptors (TLRs) and cytoplasmic sensors in innate immune cells. NAs accumulate within lysosomes due to either excessive NA influx or defective lysosomal degradation. The resultant storage of NAs and/or NA metabolites in the lysosome, referred to here as lysosomal NA stress, elicits a spectrum of responses, ranging from inflammation to tissue repair, through NA sensor activation. Although these responses contribute to host defense against infection, they may also drive diseases. For instance, loss of function of the lysosomal nucleoside transporter SLC29A3 drives lysosomal nucleoside stress, which activates TLR8 in macrophages to cause histiocytic diseases collectively called SLC29A3 disorders. Similarly, DNase II deficiency promotes lysosomal DNA stress, leading to activation of cytoplasmic double-stranded DNA sensors, such as cGAS-STING and AIM2, and thereby autoinflammatory and autoimmune diseases. Thus, lysosomal NA stress is viewed as a pivotal environmental signal that initiates innate immune responses.
    Keywords:  DNase; RNase; nucleoside; transporter
    DOI:  https://doi.org/10.1093/jb/mvaf011
  43. Bioorg Med Chem Lett. 2025 Mar 02. pii: S0960-894X(25)00069-1. [Epub ahead of print] 130160
    Bulky substrates of isoleucine 2-epimerase: α-Neopentylglycine and NV-5138.
    Noa T Sorbara, Amanda K A Black, Stephen L Bearne.
      Isoleucine 2-epimerase from Lactobacillus buchneri (LbIleE) catalyzes the pyridoxal 5'-phosphate-dependent, reversible, racemization or epimerization of nonpolar amino acids at the C-2 position. The integral role of the enzyme in the biosynthesis of branched-chain d-amino acids makes it a potential target for the development of antimicrobial agents. Probing the hydrophobic active-site pocket with a series of alkyl boronic acids, we show that the hydrophobic pocket accommodates the neopentyl group with enhanced binding affinity relative to the sec-butyl group. Subsequently, we show that LbIleE catalyzes the racemization of l- and d-α-neopentylglycine, exhibiting binding affinities for these substrates 6- and 24-fold greater than those for l-Ile and d-allo-Ile, but with catalytic efficiencies (kcat/Km) reduced 46- and 27-fold, respectively. NV-5138 is a ligand of the leucine-binding site of Sestrin2, which activates the mechanistic target of rapamycin complex1 (mTORC1) and is structurally similar to α-neopentylglycine. Our demonstration that LbIleE catalyzes the racemization of l-NV-5138 (kcat/Km = 2.2 ± 0.2 s-1 M-1), along with the fact that L. buchneri can be present in the human gut microbiome, suggests that formation of d-NV-5138 could occur in humans when l-NV-5138 is used as a pharmacological intervention for depression.
    Keywords:  Alkyl boronic acid; Isoleucine epimerase; NV-5138; Substrate specificity; α-Neopentylglycine
    DOI:  https://doi.org/10.1016/j.bmcl.2025.130160
  44. iScience. 2025 Feb 21. 28(2): 111814
    Urolithin A provides cardioprotection and mitochondrial quality enhancement preclinically and improves human cardiovascular health biomarkers.
    Sophia Liu, Julie Faitg, Charlotte Tissot, Dimitris Konstantopoulos, Ross Laws, Guillaume Bourdier, Pénélope A Andreux, Tracey Davey, Hector Gallart-Ayala, Julijana Ivanisevic, Anurag Singh, Chris Rinsch, David J Marcinek, Davide D'Amico.
      Cardiovascular diseases (CVDs) remain the primary cause of global mortality. Nutritional interventions hold promise to reduce CVD risks in an increasingly aging population. However, few nutritional interventions are proven to support heart health and act mostly on blood lipid homeostasis rather than at cardiac cell level. Here, we show that mitochondrial quality dysfunctions are common hallmarks in human cardiomyocytes upon heart aging and in chronic conditions. Preclinically, the post-biotic and mitophagy activator, urolithin A (UA), reduced both systolic and diastolic cardiac dysfunction in models of natural aging and heart failure. At a cellular level, this was associated with a recovery of mitochondrial ultrastructural defects and mitophagy. In humans, UA supplementation for 4 months in healthy older adults significantly reduced plasma ceramides clinically validated to predict CVD risks. These findings extend and translate UA's benefits to heart health, making UA a promising nutritional intervention to support cardiovascular function as we age.
    Keywords:  Biological sciences; Cardiovascular medicine; Health sciences; Internal medicine; Medical specialty; Medicine; Natural sciences; Physiology
    DOI:  https://doi.org/10.1016/j.isci.2025.111814
  45. Int J Biol Macromol. 2025 Mar 03. pii: S0141-8130(25)02281-0. [Epub ahead of print] 141730
    The role of the poly(A) binding protein-binding protein MoPbp1 as a regulator of the TOR signaling pathway in growth, autophagy, and pathogenicity of the rice blast fungus.
    Junlian Xiao, Xiaoru Kang, Na Li, Jinmei Hu, Yu Wang, Jianyu Si, Yuemin Pan, Shulin Zhang.
      The target of the rapamycin (TOR) signaling pathway is crucial for biological function in plant pathogenic fungi, yet its regulatory mechanisms remain limited. In this study, the biological functions of MoPbp1 were identified and characterized, and the findings indicate that MoPbp1 contributes to hyphal growth, conidiation, appressoria formation, metabolism of glycogen and lipid droplets, responses to stress, and pathogenicity in M. oryzae. Further investigation revealed that MoPBP1 acts as a negative regulator of TOR activity and influences autophagy. In addition, transcriptome data revealed that MoPBP1 mainly regulates amino acid metabolism pathways, components of membrane, and oxidation-reduction process. Our results suggest that MoPbp1 is required for autophagy and pathogenicity in M. oryzae. Overall, we first revealed the relationship between Pbp1 and TOR activity in plant pathogenic fungi.
    Keywords:  Autophagy; Magnaporthe oryzae; Pathogenicity; Regulation; TOR signaling pathway
    DOI:  https://doi.org/10.1016/j.ijbiomac.2025.141730
  46. J Hepatol. 2025 Mar 04. pii: S0168-8278(25)00138-2. [Epub ahead of print]
    Circadian Control of Hepatic Ischemia/Reperfusion Injury via HSD17B13-Mediated Autophagy in Hepatocytes.
    Hui Wang, Meina Guo, Baoyin Ren, Haibo Zhang, Jiayang Zhang, Rongfang Qiao, Lei Qian, Jingwen Zhu, Shuying Zhang, Xiaoyan Zhang, Guangrui Yang, Youfei Guan, Lihong Chen.
       BACKGROUND & AIMS: Studies have illustrated the role of circadian rhythm in hepatic ischemia/reperfusion injury (HIRI), but the mechanisms are poorly understood. Bmal1 is the most important gene that plays significant roles in the circadian control of liver physiology and disease, however, its role in HIRI has not been investigated. Here, we aimed to explore the potential contribution of BMAL1 to HIRI.
    METHODS: The impact of ischemia/reperfusion (I/R) timing (ZT0 vs. ZT12) on liver damage were assessed in mice with Bmal1 specifically depleted in hepatocytes or myeloid cells. RNA sequencing and other multiple molecular biology experiments were employed to explore the molecular mechanisms. Additionally, we investigated the role of HSD17B13, a lipid droplet-associated protein, in BMAL1-mediated circadian control of HIRI by utilizing global knockout, hepatocyte-specific knockdown, or hepatocyte-specific humanized HSD17B13 overexpression mouse models.
    RESULTS: We found that initiating I/R operations at ZT12 resulted in significantly more severe liver injury in wild-type mice compared to ZT0. Bmal1 in hepatocytes, but not in myeloid cells, mediated this temporal difference. Mechanistically, BMAL1 regulates the diurnal oscillation of HIRI by directly controlling Hsd17b13 transcription via binding to E-box-like elements. Hepatocyte-specific knockdown of Hsd17b13 blunted the diurnal variation of HIRI and exacerbated ZT0 HIRI. Furthermore, depletion of the BMAL1/HSD17B13 axis may inhibit lipid degradation by blocking autophagy flux, contributing to lipid overload and exacerbating HIRI. Finally, we demonstrated that hepatocyte-specific overexpression of humanized HSD17B13 may confer protection during ZT0 HIRI but aggravate damage at ZT12.
    CONCLUSIONS: Our study uncovers a pivotal role of hepatocyte BMAL1 in modulating circadian rhythms in HIRI via HSD17B13-mediated autophagy and offers a promising strategy for preventing and treating HIRI by targeting the BMAL1/HSD17B13 axis.
    IMPACT AND IMPLICATIONS: This study unveils a pivotal role of the BMAL1/HSD17B13 axis in the circadian control of hepatic ischemia/reperfusion injury, providing new insights into the prevention and treatment of hepatic ischemia/reperfusion injury. The findings have scientific implications as they enhance our understanding of the circadian regulation of hepatic ischemia/reperfusion injury. Furthermore, clinically, this research offers opportunities for optimizing treatment strategies in hepatic ischemia/reperfusion injury by considering the timing of therapeutic interventions.
    Keywords:  Autophagy; BMAL1; Circadian rhythm; HSD17B13; Hepatic ischemia/reperfusion injury; Lipid accumulation
    DOI:  https://doi.org/10.1016/j.jhep.2025.02.029
  47. Acta Pharm Sin B. 2025 Jan;15(1): 657-660
    Microglial APOE4 promotes neuron degeneration in Alzheimer's disease through inhibition of lipid droplet autophagy.
    Meng Mao, Xiwen Ma, Xiaochuan Wang, Jianping Ye.
      
    Keywords:  ACSL1; APOE4; Alzheimer's disease (AD); Lipid droplets; Microglia
    DOI:  https://doi.org/10.1016/j.apsb.2024.10.009
  48. Life Sci Alliance. 2025 May;pii: e202402934. [Epub ahead of print]8(5):
    Axonal transport of CHMP2b is regulated by kinesin-binding protein and disrupted by CHMP2bintron5.
    Konner R Kirwan, Veria Puerta-Alvarado, Clarissa L Waites.
      CHMP2b is a core component of the ESCRT pathway that catalyzes formation of multivesicular bodies for endolysosomal protein degradation. Although mutation/loss-of-function of CHMP2b promotes presynaptic dysfunction and degeneration, indicating its critical role in presynaptic protein homeostasis, the mechanisms responsible for CHMP2b localization and recruitment to synapses remain unclear. Here, we characterize CHMP2b axonal trafficking and show that its transport and recruitment to presynaptic boutons, as well as its cotransport with other ESCRT proteins, are regulated by neuronal activity. In contrast, the frontotemporal dementia-causative CHMP2bintron5 mutation exhibits little processive movement or presynaptic localization in the presence or absence of neuronal activity. Instead, CHMP2bintron5 transport vesicles exhibit oscillatory behavior reminiscent of a tug-of-war between kinesin and dynein motor proteins. We show that this phenotype is caused by deficient binding of CHMP2bintron5 to kinesin-binding protein, which we identify as a key regulator of CHMP2b transport. These findings shed light on the mechanisms of CHMP2b axonal trafficking and synaptic localization, and their disruption by CHMP2bintron5.
    DOI:  https://doi.org/10.26508/lsa.202402934
  49. bioRxiv. 2025 Feb 19. pii: 2025.02.18.638932. [Epub ahead of print]
    CHIP protects lysosomes from CLN4 mutant-induced membrane damages.
    Juhyung Lee, Jizhong Zou, Wan Nur Atiqah Binti Mazli, Natalie Chin, Michal Jarnik, Layla Saidi, Yue Xu, John Replogle, Michael Ward, Juan Bonifacino, Wei Zheng, Ling Hao, Yihong Ye.
      Understanding how cells mitigate lysosomal damage is critical for unraveling pathogenic mechanisms of lysosome-related diseases. Here we use organelle-specific proteomics in iPSC-derived neurons (i3Neuron) and an in vitro lysosome-damaging assay to demonstrate that lysosome damage, caused by the aggregation of Ceroid Lipofuscinosis Neuronal 4 (CLN4)-linked DNAJC5 mutants on lysosomal membranes, serves as a critical pathogenic linchpin in CLN4-associated neurodegeneration. Intriguingly, in non-neuronal cells, a ubiquitin-dependent microautophagy mechanism downregulates CLN4 aggregates to counteract CLN4-associated lysotoxicity. Genome-wide CRISPR screens identify the ubiquitin ligase CHIP as a central microautophagy regulator that confers ubiquitin-dependent lysosome protection. Importantly, CHIP's lysosome protection function is transferrable, as ectopic CHIP improves lysosomal function in CLN4 i3Neurons, and effectively alleviates lipofuscin accumulation and neurodegeneration in a Drosophila CLN4 disease model. Our study establishes CHIP-mediated microautophagy as a key organelle damage guardian that preserves lysosome integrity, offering new insights into therapeutic development for CLN4 and other lysosome-related neurodegenerative diseases.
    Keywords:  CHIP/STUB1; Ceroid Lipofuscinosis Neuronal/CLN4; DNAJC5/CSPα; Drosophila disease model; autophagy/microautophagy; lysosome membrane damage; lysosome storage disease/LSD; neurodegenerative disease; ubiquitin
    DOI:  https://doi.org/10.1101/2025.02.18.638932
  50. J Biol Chem. 2025 Mar 04. pii: S0021-9258(25)00230-3. [Epub ahead of print] 108381
    The ROGDI protein mutated in Kohlschutter-Tonz syndrome is a novel subunit of the Rabconnectin-3 complex implicated in V-ATPase assembly.
    Samuel R Winkley, Patricia M Kane.
      V-ATPases are highly conserved ATP-driven rotary proton pumps found widely among eukaryotes that are composed of two subcomplexes: V1 and V0. V-ATPase activity is regulated in part through reversible disassembly, during which V1 physically separates from V0 and both subcomplexes become inactive. Reassociation of V1 to V0 reactivates the complex for ATP-driven proton pumping and organelle acidification. V-ATPase reassembly in S. cerevisiae requires the RAVE complex (Rav1, Rav2, and Skp1) and higher eukaryotes, including humans, utilize the Rabconnectin-3 complex. Mammalian Rabconnectin-3 has two subunits: Rabconnectin-3α and Rabconnectin-3β. Rabconnectin-3α isoforms are homologous to Rav1, but there is no known Rav2 homolog and the molecular basis of the interaction between the Rabconnectin-3α and β subunits is unknown. We identified ROGDI as a Rav2 homolog and novel Rabconnectin-3 subunit. ROGDI mutations cause Kohlschutter-Tonz syndrome, an epileptic encephalopathy with amelogenesis imperfecta that has parallels to V-ATPase-related disease. ROGDI shares extensive structural homology with yeast Rav2 and can functionally replace Rav2 in yeast. ROGDI binds to the N-terminal domains of both Rabconnectin-3 α and β, similar to Rav2 binding to Rav1. Molecular modeling suggests that ROGDI may bridge the two Rabconnectin-3 subunits. ROGDI co-immunoprecipitates with Rabconnectin-3 subunits from detergent-solubilized lysates and is present with them in immunopurified lysosomes of mammalian cells. In immunofluorescence microscopy, ROGDI partially localizes with Rabconnectin-3α in acidic, perinuclear lysosomes. The discovery of ROGDI as a novel Rabconnectin-3 interactor sheds new light on both Kohlschutter-Tonz syndrome and the mechanisms behind mammalian V-ATPase regulation.
    Keywords:  ATPase; DMXL1; ROGDI; Rabconnectin-3; V-ATPase; WDR7; lysosomal acidification; lysosome; protein assembly; protein-protein interaction
    DOI:  https://doi.org/10.1016/j.jbc.2025.108381
  51. J Transl Med. 2025 Mar 04. 23(1): 269
    Important regulatory role of mitophagy in diabetic microvascular complications.
    Xiangjie Hu, Jiao Lv, Yunyun Zhao, Xiangyan Li, Wenxiu Qi, Xiuge Wang.
      Microvascular complications of diabetes pose a significant threat to global health, mainly including diabetic kidney disease (DKD), diabetic retinopathy (DR), diabetic peripheral neuropathy (DPN), and diabetic cardiomyopathy (DCM), which can ultimately lead to kidney failure, blindness, disability, and heart failure. With the increasing prevalence of diabetes, the search for new therapeutic targets for diabetic microvascular complications is imminent. Mitophagy is a widespread and strictly maintained process of self-renewal and energy metabolism that plays an important role in reducing inflammatory responses, inhibiting reactive oxygen species accumulation, and maintaining cellular energy metabolism. Hyperglycemia results in impaired mitophagy, which leads to mitochondrial dysfunction and ultimately exacerbates disease progression. This article summarizes the relevant molecular mechanisms of mitophagy and reviews the current status of research on regulating mitophagy as a potential treatment for diabetic microvascular complications, attempting to give new angles on the treatment of diabetic microvascular complications.
    Keywords:  Diabetic cardiomyopathy; Diabetic kidney disease; Diabetic peripheral neuropathy; Diabetic retinopathy; Mitophagy
    DOI:  https://doi.org/10.1186/s12967-025-06307-7
  52. Free Radic Biol Med. 2025 Mar 01. pii: S0891-5849(25)00130-3. [Epub ahead of print]232 72-85
    Astragalin actives autophagy and inhibits apoptosis of astrocytes in AD mice via down-regulating Fas/Fasl-VDAC1 pathway.
    Shuhan Wang, Yaqi Yang, Jiahong Lin, Weishan Zhang, Cuizhu Yang, Runheng Zhang, Chang Zhou, Li Zhang, Xin Wang, Jing Liu, Xiaobao Jin, Yuxin Ma.
      Alzheimer's disease (AD) as a common neurodegenerative disease, which characterized by amyloid Aβ deposition and neurofibrillary tangles. Astragalin (AST), a natural flavonoid, has anti-inflammatory, antioxidant, anti-cancer, and other pharmacological effects. Astrocytes can phagocytize and degrade Aβ in their vicinity. In this study, we used the AD mice model established by injecting the mixture of Aβ1-42 and Aβ25-35 into the CA1 region of the hippocampus, and C8D1A cells injured by Aβ1-42 to explore the neuroprotective effects of AST. Our findings showed that AST enhances learning and cognitive ability of AD mice, reduces Aβ deposition and neurofibrillary tangles in the brain, and improves the structural morphology of hippocampal nerve cells. Furthermore, AST promoted autophagy and suppressed apoptosis of astrocytes in the AD model. Additionally, AST inhibited the expression of proteins associated with the Fas/Fasl-VDAC1 signaling pathway, while autophagy inhibitor chloroquine (CQ) or apoptosis agonist phenoxodiol reversed above change. Interestingly, consistent with the action of pathway Fas inhibitor KR-33493, AST could activate autophagy of Aβ1-42 injured C8D1A cells while inhibit their apoptosis. In conclusion, AST activated autophagy and inhibited apoptosis of hippocampal astrocytes in AD mice, ameliorating animal cognitive deficits by down-regulating Fas/Fasl-VDAC1 signaling pathway. Thus, this study provided a new perspective and experimental foundation for developing AD treatment drugs.
    Keywords:  Alzheimer's disease; Apoptosis; Astragalin; Astrocyte; Autophagy; Aβ; C8D1A
    DOI:  https://doi.org/10.1016/j.freeradbiomed.2025.02.047
  53. J Neuroinflammation. 2025 Feb 28. 22(1): 55
    Protective role of mitophagy on microglia-mediated neuroinflammatory injury through mtDNA-STING signaling in manganese-induced parkinsonism.
    Yang Lu, Liang Gao, Yuqing Yang, Dihang Shi, Zhipeng Zhang, Xiaobai Wang, Ying Huang, Jie Wu, Jia Meng, Hong Li, Dongying Yan.
      Manganese (Mn), the third most abundant transition metal in the earth's crust, has widespread applications in the emerging field of organometallic catalysis and traditional industries. Excessive Mn exposure causes neurological syndrome resembling Parkinson's disease (PD). The pathogenesis of PD is thought to involve microglia-mediated neuroinflammatory injury, with mitochondrial dysfunction playing a role in aberrant microglial activation. In the early stages of PD, PINK1/Parkin-mediated mitophagy contributes to the microglial inflammatory response via the cGAS/STING signaling pathway. Suppression of PINK1/Parkin-mediated mitophagy due to excessive Mn exposure exacerbates neuronal injury. Moreover, excessive Mn exposure leads to neuroinflammatory damage via the microglial cGAS-STING pathway. However, the precise role of microglial mitophagy in modulating neuroinflammation in Mn-induced parkinsonism and its underlying molecular mechanism remains unclear. Here, we observed that Mn-exposed mice exhibited neurobehavioral abnormalities and detrimental microglial activation, along with increased apoptosis of nerve cells, proinflammatory cytokines, and intracellular ROS. Furthermore, in vivo and in vitro experiments showed that excessive Mn exposure resulted in microglial mitochondrial dysfunction, manifested by increased mitochondrial ROS, decreased mitochondrial mass, and membrane potential. Additionally, with the escalating Mn dose, PINK1/Parkin-mediated mitophagy changed from activation to suppression. This was evidenced by decreased levels of LC3-II, PINK1, p-Parkin/Parkin, and increased levels of p62 protein expression level, as well as the colocalization between ATPB and LC3B due to excessive Mn exposure. Upregulation of mitophagy by urolithin A could mitigate Mn-induced mitochondrial dysfunction, as indicated by decreased mitochondrial ROS, increased mitochondrial mass, and membrane potential, along with improvements in neurobehavioral deficits and attenuated detrimental microglial activation. Using single-nucleus RNA-sequencing (snRNA-seq) analysis in the Mn-exposed mouse model, we identified the microglial cGAS-STING signaling pathway as a potential mechanism underlying Mn-induced neuroinflammation. This pathway is associated with an increase in cytosolic mtDNA levels, which activate STING signaling. These findings point to the induction of microglial mitophagy as a viable strategy to alleviate Mn-induced neuroinflammation through mtDNA-STING signaling.
    Keywords:  Manganese; Microglia; Mitophagy; Neuroinflammation; STING
    DOI:  https://doi.org/10.1186/s12974-025-03396-5
  54. Aging Cell. 2025 Mar 03. e70008
    Rejuvenation of Senescent Cells, In Vitro and In Vivo, by Low-Frequency Ultrasound.
    Sanjay K Kureel, Rosario Maroto, Maisha Aniqua, Simon Powell, Ekta Singh, Felix Margadant, Brandon Blair, Blake B Rasmussen, Michael P Sheetz.
      The presence of senescent cells causes age-related pathologies since their removal by genetic or pharmacological means, as well as possibly by exercise, improves outcomes in animal models. An alternative to depleting such cells would be to rejuvenate them to promote their return to a replicative state. Here we report that treatment of non-growing senescent cells with low-frequency ultrasound (LFU) rejuvenates the cells for growth. Notably, there are 15 characteristics of senescent cells that are reversed by LFU, including senescence-associated secretory phenotype (SASP) plus decreased cell and organelle motility. There is also inhibition of β-galactosidase, p21, and p16 expression, telomere length is increased, while nuclear 5mC, H3K9me3, γH2AX, nuclear p53, ROS, and mitoSox levels are all restored to normal levels. Mechanistically, LFU causes Ca2+ entry and increased actin dynamics that precede dramatic increases in autophagy and an inhibition of mTORC1 signaling plus movement of Sirtuin1 from the nucleus to the cytoplasm. Repeated LFU treatments enable the expansion of primary cells and stem cells beyond normal replicative limits without altering phenotype. The rejuvenation process is enhanced by co-treatment with cytochalasin D, rapamycin, or Rho kinase inhibition but is inhibited by blocking Sirtuin1 or Piezo1 activity. Optimized LFU treatment parameters increased mouse lifespan and healthspan. These results indicate that mechanically induced pressure waves alone can reverse senescence and aging effects at the cellular and organismal level, providing a non-pharmacological way to treat the effects of aging.
    Keywords:  aging; autophagy; calcium signaling; low frequency ultrasound; rejuvenation; senescence
    DOI:  https://doi.org/10.1111/acel.70008
  55. Cell Death Discov. 2025 Feb 28. 11(1): 80
    Loss of TC-PTP in keratinocytes leads to increased UVB-induced autophagy.
    Obed Asare, Lindsey Shim, Cheol-Jung Lee, Jose Delgado, Natasha Quailes, Klarissa Zavala, Junsoo Park, Bilal Bin Hafeez, Yong-Yeon Cho, Subhash C Chauhan, Dae Joon Kim.
      Ultraviolet B (UVB) radiation can distort cellular homeostasis and predispose the skin to carcinogenesis. Amongst the deteriorating effects of the sun's UVB radiation on cellular homeostasis is the formation of DNA photoproducts. These photoproducts can cause significant changes in the structure and conformation of DNA, inducing gene mutations which may accumulate to trigger the formation of skin cancer. Photoproducts are typically repaired by nucleotide excision repair. Notwithstanding, when the repair mechanism fails, apoptosis ensues to prevent the accumulation of mutations and to restore cellular homeostasis. This present study reports that T-cell protein tyrosine phosphatase (TC-PTP) can increase UVB-induced apoptosis by inhibiting autophagy-mediated cell survival of damaged keratinocytes. TC-PTP deficiency in 3PC mouse keratinocytes led to the formation of autophagic vacuoles and increased expression of LC3-II. We established human TC-PTP-deficient (TC-PTP/KO) HaCaT cells using the CRISPR/Cas9 system. TC-PTP/KO HaCaT cells exhibited increased cell survival upon UVB exposure, which was accompanied by increased expression of LC3-II and decreased expression of p62 compared to control cells. Pretreatment of TC-PTP/KO HaCaT cells with early-phase autophagy inhibitor, 3-methyladenine significantly decreased the expression of LC3-II and reduced cell survival in response to UVB irradiation in comparison with untreated TC-PTP/KO cells. Pretreatment of TC-PTP/KO HaCaT cells with late-phase inhibitor, chloroquine also significantly reduced cell viability with increased accumulation of LC3-II after UVB irradiation compared to untreated counterpart cells. While UVB significantly increased apoptosis in the engineered (Mock) cells, this was not observed in similarly treated TC-PTP/KO HaCaT cells. However, chloroquine treatment increased apoptosis in TC-PTP/KO HaCaT cells. Examination of human squamous cell carcinomas (SCCs) revealed that TC-PTP expression was inversely correlated with LC3 expression. Our findings suggest that TC-PTP negatively regulates autophagy-mediated survival of damaged cells following UVB exposure, which can contribute to remove damaged keratinocytes via apoptosis.
    DOI:  https://doi.org/10.1038/s41420-025-02353-8
  56. NPJ Metab Health Dis. 2025 ;3(1): 8
    AMPK phosphosite profiling by label-free mass spectrometry reveals a multitude of mTORC1-regulated substrates.
    William J Smiles, Ashley J Ovens, Dingyi Yu, Naomi X Y Ling, Andrea C Poblete Goycoolea, Kaitlin R Morrison, Emmanuel O Murphy, Astrid Glaser, Sophie F Monks O'Byrne, Scott Taylor, Alistair M Chalk, Carl R Walkley, Luke M McAloon, John W Scott, Bruce E Kemp, Ashfaqul Hoque, Christopher G Langendorf, Janni Petersen, Sandra Galic, Jonathan S Oakhill.
      The nutrient-sensitive protein kinases AMPK and mTORC1 form a fundamental negative feedback loop that governs cell growth and proliferation. mTORC1 phosphorylates α2-S345 in the AMPK αβγ heterotrimer to suppress its activity and promote cell proliferation under nutrient stress conditions. Whether AMPK contains other functional mTORC1 substrates is unknown. Using mass spectrometry, we generated precise stoichiometry profiles of phosphorylation sites across all twelve AMPK complexes expressed in proliferating human cells and identified seven sites displaying sensitivity to pharmacological mTORC1 inhibition. These included the abundantly phosphorylated residues β1-S182 and β2-S184, which were confirmed as mTORC1 substrates on purified AMPK, and four residues in the unique γ2 N-terminal extension. β-S182/184 phosphorylation was elevated in α1-containing complexes relative to α2, an effect attributed to the α-subunit serine/threonine-rich loop. Mutation of β1-S182 to non-phosphorylatable Ala had no effect on basal and ligand-stimulated AMPK activity; however, β2-S184A mutation increased nuclear AMPK activity, enhanced cell proliferation under nutrient stress and altered expression of genes implicated in glucose metabolism and Akt signalling. Our results indicate that mTORC1 directly or indirectly phosphorylates multiple AMPK residues that may contribute to metabolic rewiring in cancerous cells.
    Keywords:  Biochemistry; Biological techniques; Cancer
    DOI:  https://doi.org/10.1038/s44324-025-00052-7
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