bims-miptne 2025-11-16 papers

bims-miptne

Biomed News

on Mitochondrial permeability transition pore-dependent necrosis

Issue of 2025–11–16
thirteen papers selected by
Oluwatobi Samuel Adegbite, University of Liverpool

Glutaredoxin 2 is essential for AML survival through mitochondrial permeability transition pore regulation.
Mitochondrial Calcium Channels and MAM Interaction in Calcium Homeostasis Dysregulation in Parkinson's Disease.
Potent Preorganized Pyrazolidine Cyclophilin D Inhibitors Prevent Mitochondrial and Organ Injury in a Mouse Pancreatitis Disease Model.
Calcium Regulation of Mitochondrial Metabolism.
Mitochondrial Ca2+ overload is a pivotal risk factor for lethal ventricular arrhythmias due to the oxidation of mitochondrial respirasome and energetic failure.
MPTP mediated Ox-mtDNA release inducing macrophage pyroptosis and exacerbating MCD-induced MASH via promoting the ITPR3/Ca2+/NLRP3 pathway.
Calcium Homeostasis Machinery in the Human Uterus-A Potential Therapeutic Target in Endometrial Cancer.
The tumor suppressor LACTB remodels mitochondria to promote cytochrome c release and apoptosis.
Peroxynitrite regulates ER stress-mediated Ca2+ flux to mitochondria characterizing cardiac microvascular ischemia-reperfusion injury associated with hyperhomocysteinemia.
Mitochondrial-ER crosstalk: An emerging mechanism in the pathophysiology of pulmonary arterial hypertension.
Assessment of mitochondrial viability under calcium Stress: Insights for mitochondrial transplantation.
Hypoxia-preconditioning human bone marrow-derived mesenchymal stem cells induce high-quality mitochondrial transfer through gap junctions to alleviate ischemia-reperfusion injury in liver graft.
Integration of single-cell and bulk transcriptomics to explore prognostic and immunotherapeutic characteristics of sodium overload-induced cell death in lung adenocarcinoma.

Blood. 2025 Nov 14. pii: blood.2025028933. [Epub ahead of print]

Glutaredoxin 2 is essential for AML survival through mitochondrial permeability transition pore regulation.

Tianyi Ling, Cristiana O'Brien, Jonathan St-Germain, Vincent Rondeau, Mary Shi, Jacob M Berman, Adrianna Kinga Cepa, Paula Saez Raez, Mark Wunderlich, Katharine Carter, Cody Stillwell, Christina R Sexton, Rachel Culp-Hill, Julie A Reisz, Saeer A Adeel, Andy G X Zeng, Suraj Bansal, Emily Tsao, He Tian Tony Chen, John E Dick, Mark D Minden, Andrea Arruda, Maria L Amaya, Anastasia N Tikhonova, Kristin Hope, Angelo D'Alessandro, Brian Raught, Courtney L Jones.

Acute myeloid leukemia (AML) patients have a poor five-year survival rate highlighting the need for the identification of new approaches to target this disease. AML is highly dependent on glutathione (GSH) metabolism for survival. While the metabolic role of GSH is well-characterized in AML, the contribution of protein glutathionylation-a reversible modification that protects protein thiols from oxidative damage-remains largely unexplored. Therefore, we sought to elucidate the role of protein glutathionylation in AML pathogenesis. Here, we demonstrate that protein glutathionylation is essential for AML cell survival. Specifically, the loss of glutaredoxin 2 (GLRX2), an enzyme that removes glutathione modifications, resulted in selective primary AML cell death while sparing normal human hematopoietic stem and progenitor cells. Unbiased proteomic analysis revealed increased mitochondrial protein glutathionylation upon GLRX2 depletion, accompanied by mitochondrial dysfunction, including impaired oxidative phosphorylation, reduced mitochondrial membrane potential, and increased opening of the mitochondrial permeability transition pore (mPTP). Further investigation identified ATP5PO, a key regulator of mPTP opening and a component of the ATP synthase complex, as a critical GLRX2 target. Disruption of ATP5PO glutathionylation partially restored mPTP function and rescued AML cell viability following GLRX2 depletion. Moreover, both genetic and pharmacologic inhibition of mPTP opening restored the leukemic potential of primary AML specimens in the absence of GLRX2. By disrupting glutathionylation-dependent mitochondrial homeostasis, this study reveals a novel vulnerability in AML that could inform future therapeutic strategies.

DOI: https://doi.org/10.1182/blood.2025028933
Neurochem Res. 2025 Nov 15. 50(6): 361

Mitochondrial Calcium Channels and MAM Interaction in Calcium Homeostasis Dysregulation in Parkinson's Disease.

Bingjie Han, Jie Bai.

  Parkinson's disease (PD), the second most common neurodegenerative disorder worldwide, currently lacks effective treatment options due to its complex pathogenesis. Growing evidence in recent years demonstrates that intracellular Calcium (Ca²⁺) homeostasis disruption plays a critical role in PD development and progression. Ca²⁺ imbalance not only causes Ca²⁺-dependent synaptic dysfunction and impaired neuronal plasticity but also leads to progressive neuronal loss, collectively forming the core pathological characteristics of PD neurodegeneration. Notably, mitochondrial Ca²⁺ imbalance has been identified as a key pathogenic factor in PD. As vital intracellular Ca²⁺ regulators, dysfunctional mitochondria can induce abnormal opening of the mitochondrial permeability transition pore (mPTP), triggering apoptotic cascades. Furthermore, mitochondrial Ca²⁺ overload disrupts oxidative phosphorylation, resulting in excessive reactive oxygen species production that exacerbates neuronal damage. Recent studies reveal the essential role of mitochondria-endoplasmic reticulum interactions in maintaining Ca²⁺ homeostasis, with these organelles forming structurally and functionally integrated connections through mitochondrial ER-associated membrane (MAM) to cooperatively regulate Ca²⁺ ion dynamics. This review describes the molecular mechanisms of mitochondrial Ca²⁺ imbalance in PD pathogenesis and summarizes the potential of mitochondrial channels and MAM-associated proteins as PD therapeutic targets. By thoroughly analyzing these targets mechanisms, we aim to provide a theoretical foundation for developing novel PD treatment strategies based on Ca²⁺ homeostasis regulation. These findings not only expand our understanding of PD pathogenesis but also point toward developing targeted neuroprotective therapies.

Keywords:  Calcium homeostasis; Mitochondria; Mitochondrial endoplasmic reticulum-associated membrane; Parkinson’s disease

DOI:  https://doi.org/10.1007/s11064-025-04591-9
J Med Chem. 2025 Nov 09.

Potent Preorganized Pyrazolidine Cyclophilin D Inhibitors Prevent Mitochondrial and Organ Injury in a Mouse Pancreatitis Disease Model.

Muhammad Awais, Christopher M Woodley, Liqun Guo, Michael Rogers, Neil Kershaw, Thomas Zacharchenko, Emma Shore, Arjun Kattakayam, Rajarshi Mukherjee, David N Criddle, Suet C Leung, Heather Lee, Joshua Burgess-McCann, Konstantin Luzyanin, Neil G Berry, Svetlana Antonyuk, Lu-Yun Lian, Robert Sutton, Paul M O'Neill.

Cyclophilin D inhibitors that prevent opening of the mitochondrial permeability transition pore (MPTP) are potential treatments for a range of acute and chronic diseases, including acute pancreatitis. Here, we report that replacement of carbon with nitrogen in the pyrrolidine headgroup of a series of cyclophilin D inhibitors gives a dramatic enhancement in binding affinity (>40 fold), and prolyl isomerase inhibition (PPIase) activity (>200 fold), which is ascribed to a preorganization of the pyrazolidine amide headgroup. Protein-ligand X-ray crystal structures and NMR and molecular modeling demonstrate the importance of cis-amide geometry within the preorganized conformation, ensuring the ligand headgroup is anchored in the S1' binding pocket, leading to potent nM PPIase inhibition and binding. Pyrazolidines potently inhibit MPTP opening and prevent pancreatic toxin-induced cell necrosis in vitro. In vivo, 18f provided a significant improvement of acute pancreatitis biomarkers in the CER-AP mouse pancreatitis model, underlining the potential of this series.

DOI: https://doi.org/10.1021/acs.jmedchem.5c01146
Annu Rev Physiol. 2025 Nov 10.

Calcium Regulation of Mitochondrial Metabolism.

Carmen A Mannella, Pawel Swietach, Liron Boyman.

Mitochondrial ATP production dynamically adapts to cellular energy demands, with calcium (Ca2+) playing a crucial regulatory role. In this review, we critically evaluate the evidence for intramitochondrial Ca2+ ([Ca2+]m) sensitivity in key energy metabolic pathways, highlighting the [Ca2+]m dependence of specific mitochondrial systems. We also address the metabolic consequences of [Ca2+]m-sensitive ATP production, particularly its effects on the utilization of specific macronutrients that fuel ATP production. Next, we discuss the primary Ca2+ entry pathway into the matrix, the mitochondrial Ca2+ uniporter (MCU), its macromolecular complex structure (MCUcx), and allosteric regulation by Ca2+. Key to this regulation are specific auxiliary subunits, along with the influence of mitochondrial inner membrane architecture. While the Ca2+ signaling plays an important role, it does not fully explain the scope for regulating ATP production. Emerging evidence suggests that additional signaling systems operating alongside the Ca2+ signaling contribute to the control of mitochondrial ATP production, a topic requiring further investigation.

DOI: https://doi.org/10.1146/annurev-physiol-052424-082740
Br J Pharmacol. 2025 Nov 14.

Mitochondrial Ca2+ overload is a pivotal risk factor for lethal ventricular arrhythmias due to the oxidation of mitochondrial respirasome and energetic failure.

Felipe de Jesús Salazar-Ramírez, Luis Alberto Luévano-Martínez, Abraham Méndez-Fernández, Judith Bernal-Ramírez, Carolina A Morales-Ochoa, Christian Silva-Platas, Alfredo Cabrera-Orefice, Ana C Murrieta, José Luis Velasco-Bolom, Gricelda Mendiola-Garza, Flavio Contreras-Torres, Guillermo Torre-Amione, Ernesto A Aiello, Gerardo García-Rivas.

   BACKGROUND AND PURPOSE: Ventricular arrhythmias are a leading cause of death among patients with cardiovascular diseases and are associated with elevated levels of catecholamines. Mitochondrial Ca2+ transport is essential for initiating an adrenergic response. However, continuous stimulation might lead to mitochondrial Ca2+ overload and dysfunction within cardiac tissue. This study investigates the role of mitochondrial Ca2+ in lethal arrhythmogenesis and the effects of its modulation.
EXPERIMENTAL APPROACH: Male C57BL/6 mice were administered either Ru360 (oxo-bridged dinuclear ruthenium ammine complex) a potent and selective mitochondrial Ca2+ transport inhibitor, or normal saline via intravenous injection. A baseline electrocardiogram (ECG) was recorded, followed by subcutaneous administration of isoprenaline. The ECG was monitored for an additional 20 min, after which cardiomyocytes and mitochondria were isolated for further characterization studies.
KEY RESULTS: Isoprenaline administration led to ventricular tachycardia and fibrillation, but Ru360 pretreatment successfully prevented these arrhythmias. Mitochondria from isoprenaline-treated hearts showed higher Ca2+ content, indicating overload that compromised mitochondrial function and membrane integrity, evidenced by decreased respiratory control, reduced Ca2+ retention capacity and diminished membrane potential. Isoprenaline also increased oxidative stress, illustrated by elevated peroxide production, electron leak and acute oxidative modifications, and erratic cellular Ca2+ dynamics. This mitochondrial dysfunction correlated with a decreased respirasome activity, but not a difference in respirasome abundance quantified by complexome profiling, which was prevented by Ru360 pretreatment.
CONCLUSION: Mitochondrial Ca2+ overload significantly contributes to arrhythmias by disrupting respirasome function and increasing oxidative stress, impairing cellular Ca2+ dynamics. Modulating mitochondrial Ca2+ transport might be a promising strategy for developing innovative antiarrhythmic therapies.

Keywords:  arrhythmia; calcium; mitochondria; respirasome

DOI:  https://doi.org/10.1111/bph.70253
J Transl Med. 2025 Nov 14. 23(1): 1289

MPTP mediated Ox-mtDNA release inducing macrophage pyroptosis and exacerbating MCD-induced MASH via promoting the ITPR3/Ca2+/NLRP3 pathway.

Qi Zhang, Li Chen, Jun-Yan Liu, Tao Liu, Rui Wang, Xin-Yi Wu, Sheng-Wei Li.

   BACKGROUND: Metabolic Dysfunction-Associated Steatohepatitis (MASH) is a severe and progressive form of Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD), with approximately 25% of adults worldwide suffering from MASLD, of which 20%-30% progress to MASH, and the global incidence continues to rise. Oxidized mitochondrial DNA (Ox-mtDNA) release is a key contributor to MASH. However, its underlying mechanism remains unclear. Clarifying this process may provide a theoretical foundation for MASH treatment.
METHODS: In this study, we separately established MASH models using methionine- and choline deficient diet (MCD) fed mice in vivo and free fatty acid (FFA)-stimulated THP-1 derived macrophages in vitro. Cyclosporin A (CsA: mitochondrial permeability transition pore, mPTP, channel inhibitor) was used to inhibit the release of Ox-mtDNA. 8-OH-dG detection and fluorescent probe were used to evaluate Ox-mtDNA release. Liver lipid deposition was analyzed by Triglyceride (TG) and Oil Red O, and tissue damage were analyzed by aspartate transaminase and alanine aminotransferase (ALT, AST) and H&E staining. Pyroptosis markers, such as cleaved-Caspase1, GSDMD-N, and inflammatory cytokines, such as interleukin - 1β, interleukin 18 (IL-1β, IL-18), were detected by WB, ELISA and transmission electron microscopy (TEM) experiments, and the key pyroptosis pathways activated by Ox-mtDNA were screened by RNA-seq. Finally, ITPR3 was silenced by siRNA in vitro and by Adeno-associated virus (AAV) in vivo respectively, which confirmed the role of ITPR3/Ca2+/NLRP3 axis in Ox-mtDNA regulating macrophage pyroptosis mediated MASH.
RESULTS: The cytosolic Ox-mtDNA level was significantly increased during MASH. Inhibition of Ox-mtDNA release alleviated macrophage pyroptosis to improve the pathological phenotype of MASH. RNA-seq analysis showed that cytosolic Ox-mtDNA triggered an inflammatory response by activating the NOD-like receptor pathway, in which FFA induced upregulation of inositol 1,4,5-Trisphosphate Receptor Type 3 (ITPR3, IP3R) expression, and Inhibition of Ox-mtDNA release could relieve this effect. ITPR3 silencing significantly reduced Ca²⁺ release, which in turn inhibited nucleotide-binding domain and leucine-rich repeat protein-3 (NLRP3) inflammasome activation and macrophage pyroptosis. Cytosolic Ox-mtDNA promotes Ca²⁺ release by upregulating ITPR3, activates NLRP3-dependent macrophage pyroptosis, and ultimately exacerbates liver injury and MASH progression.
CONCLUSIONS: This study demonstrates that Ox-mtDNA drives MASH progression by promoting macrophage pyroptosis via the ITPR3/Ca²⁺/NLRP3 axis, providing a novel therapeutic strategy for targeted intervention.

Keywords:  Ca2+ ; ITPR3; MASH; NLRP3; Ox-mtDNA; Pyroptosis

DOI:  https://doi.org/10.1186/s12967-025-07302-8
Int J Mol Sci. 2025 Oct 22. pii: 10253. [Epub ahead of print]26(21):

Calcium Homeostasis Machinery in the Human Uterus-A Potential Therapeutic Target in Endometrial Cancer.

Piotr K Zakrzewski.

  Endometrial cancer is one of the most common malignancies of the female reproductive system, with incidence rising globally due to population ageing and life-style-related risk factors. Calcium (Ca2+) is a ubiquitous second messenger regulating diverse physiological processes, and its dysregulation has been increasingly implicated in carcinogenesis, including endometrial. Altered expression and function of Ca2+ channels, pumps, exchangers, and binding proteins disrupt the finely tuned balance of Ca2+ influx, efflux, and intracellular storage, leading to aberrant signalling that promotes tumour proliferation, migration, survival, and metastasis. This review summarises current knowledge on the molecular "Ca2+ toolkit" in the human uterus, highlighting the role of voltage-gated calcium channels (VGCCs), transient receptor potential (TRP) channels, store-operated calcium entry (SOCE) components, Na+/Ca2+ exchangers, purinergic receptors, P-type ATPases (SERCA, SPCA, PMCA), ryanodine (RyR) and inositol 1,4,5-trisphosphate (IP3R) receptors, and mitochondrial Ca2+ uniporter (MCU) complexes in endometrial cancer progression. Multiple Ca2+-handling proteins, including CACNA1D, CACNA2D1, TRPV4, TRPV1, TRPM4, MCU, and RyR1, exhibit cancer-associated overexpression or functional changes, correlating with poor prognosis and aggressive disease features. Emerging evidence supports the therapeutic potential of targeting Ca2+ homeostasis using small-molecule inhibitors, ion channel modulators or gene-silencing strategies. These interventions may restore Ca2+ balance, induce apoptosis or autophagy, and suppress metastatic behaviour. While no clinical trials have yet explicitly focused on Ca2+ modulation in endometrial cancer, the diversity of dysregulated Ca2+ pathways offers a rich landscape for novel therapeutic strategies. Targeting key components of the Ca2+ signalling network holds promise for improving outcomes in endometrial cancer.

Keywords:  calcium; endometrial cancer; novel therapies

DOI:  https://doi.org/10.3390/ijms262110253
Sci Adv. 2025 Nov 14. 11(46): eadx7809

The tumor suppressor LACTB remodels mitochondria to promote cytochrome c release and apoptosis.

Sukrut C Kamerkar, Taewook Kang, Radu V Stan, Edward J Usherwood, Henry N Higgs.

Mitochondria are pivotal regulators of cellular homeostasis, integrating energy metabolism, biosynthesis, and programmed cell death (apoptosis). During apoptosis, mitochondrial outer membrane permeabilization by BCL-2-associated X protein/BCL-2 Homolog Antagonist Killer (BAX/BAK) pores facilitates release of apoptotic factors, while the role of inner mitochondrial membrane (IMM) remodeling remains less understood. Here, we identify serine beta-lactamase-like protein (LACTB), a filament-forming serine protease and tumor suppressor, as a regulator of IMM dynamics during apoptosis. LACTB suppression reduces cytochrome c release and apoptosis, whereas its overexpression promotes these effects. LACTB does not affect BAX or Drp1 recruitment to mitochondria. Rather, LACTB is required for apoptosis-induced mitochondrial remodeling, independent of OPA1 processing. Intriguingly, LACTB knockdown does not affect mitochondrial shape changes induced by CCCP treatment, suggesting that LACTB action is apoptosis-specific. Purified LACTB binds and remodels cardiolipin-enriched membrane nanotubes preferentially over planar lipid membranes, suggesting a direct effect in apoptotic membrane remodeling. Collectively, our findings suggest LACTB to be a mediator of apoptosis-induced IMM remodeling, a possible mechanism for tumor suppression in cancer.

DOI: https://doi.org/10.1126/sciadv.adx7809
J Transl Med. 2025 Nov 10. 23(1): 1254

Peroxynitrite regulates ER stress-mediated Ca2+ flux to mitochondria characterizing cardiac microvascular ischemia-reperfusion injury associated with hyperhomocysteinemia.

Haipeng Liu, Siyang Yu, Shansong Gao, Xiaoming Liu, Chengpeng Qiu, Ning Wang, Xinyu Tan, Kaiyang Zhao, Qiuyu He, Wan Zhang.

   BACKGROUND: Homocysteine (Hcy) is not only associated with the development of chronic cardiovascular diseases like atherosclerosis, but may also participate in the acute cardiovascular events. However, the exact mechanism of the latter remains elusive. The present study aims to further investigate the mechanism of cardiac microvascular endothelial cells (CMECs) death after I/R induction in the presence of Hcy and explore new therapeutic strategies.
METHODS: By generating the hypoxia/reoxygenation (H/R) human cardiac microvascular endothelial cell (HCMEC) model and the I/R models in rats with hyperhomocysteinemia (HHcy), the mechanisms of endothelial cell injury associated with HHcy were investigated.
RESULTS: We demonstrated that ONOO-, generated by the combination of Hcy and Cu2+ during I/R, induces ER stress and the subsequent ER-mitochondria Ca2+ transfer via IP3R-mediated Ca2+ release in CMECs. The cytosolic/mitochondrial Ca2+ oscillations and mitochondrial Ca2+ overload promote mROS generation, provoke LMP, and ultimately drive CMEC necroptosis. Our study further demonstrates the IP3R inhibitor 2-APB (5 mg/kg) significantly reduced infarct size by 29.14%, and improved cardiac function in HHcy rats (HHcyR), as evidenced by increased LVEF (35.71% → 55.32%), elevated LVFS (31.44% → 48.54%), and reduced LVEDd (6.98 mm → 5.80 mm).
CONCLUSIONS: Altogether, our results reveal the pathological role of Hcy in acute cardiovascular events. We show that HHcy aggravates cardiac microvascular I/R injury via ONOO--driven ER stress that triggers IP3R-mediated Ca2+ mis-handling, culminating in mitochondrial dysfunction and necroptosis. These data identify IP3R-dependent Ca2+ transfer as a tractable pathway for HHcy-complicated reperfusion injury.

Keywords:  Ca2+ dyshomeostasis; Cardiac microvascular ischemia-reperfusion injury; Hyperhomocysteinemia; Necroptosis; ROS amplification

DOI:  https://doi.org/10.1186/s12967-025-07263-y
Mitochondrion. 2025 Nov 10. pii: S1567-7249(25)00091-1. [Epub ahead of print] 102094

Mitochondrial-ER crosstalk: An emerging mechanism in the pathophysiology of pulmonary arterial hypertension.

Gauri Chaturvedi, Nandini Dubey, Pranav Panchbhai, Satnam Singh, Ravinder Singh, Upendra Baitha, Neeraj Parakh, Rajiv Narang, Harlokesh Narayan Yadav.

  Pulmonary arterial hypertension (PAH) is a progressive and fatal disease characterized by hyperproliferation and remodeling of the pulmonary vasculature, primarily affecting pulmonary arterial smooth muscle cells (PASMCs) and pulmonary arterial endothelial cells (PAECs). Although several pharmacological agents target the known signaling pathways in these cells, current therapies fail to reverse vascular remodeling, underscoring the urgent need for novel therapeutic strategies. Recent research has shifted focus towards intracellular organelles, specifically mitochondria and the endoplasmic reticulum (ER), as potential therapeutic targets. A key area of interest is mitochondria-associated membranes (MAMs), specialized contact sites between mitochondria and the ER that regulate essential cellular processes, including calcium homeostasis, ER stress signaling, autophagy, and insulin signaling. This review explores the emerging role of MAMs in the pathogenesis of PAH, detailing the molecular players involved in MAM formation and function. Emphasis is placed on identifying MAM-associated proteins that are dysregulated in PASMCs and PAECs, providing insights into their potential as novel therapeutic targets in PAH.

Keywords:  Novel therapeutic targets; PAECs; PASMCs; Pulmonary arterial hypertension; mitochondria-ER associated membranes

DOI:  https://doi.org/10.1016/j.mito.2025.102094
Mitochondrion. 2025 Nov 12. pii: S1567-7249(25)00095-9. [Epub ahead of print] 102098

Assessment of mitochondrial viability under calcium Stress: Insights for mitochondrial transplantation.

Melody Toosky, Arash Kheradvar.

  Mitochondrial transplantation has emerged as a promising cardioprotective strategy for ischemia-reperfusion injury, aiming to restore bioenergetic function by delivering healthy mitochondria to damaged tissue. However, conflicting reports exist regarding whether mitochondria can survive exposure to the calcium-rich extracellular environment, such as the bloodstream, prior to cellular uptake. Resolving this question is essential for advancing the therapeutic use of mitochondria in clinical settings. Isolated mitochondria from L6 rat skeletal muscle cells were incubated with physiologic (1.3  mM), sub-physiologic (0.65  mM), and supraphysiologic (2.6  mM) concentrations of calcium. Mitochondrial membrane potential was assessed using MitoTracker™ Red FM fluorescence, and structural integrity was evaluated using impedance-based Coulter counter analysis over a 12-hour time course. Mitochondria exposed to 1.3  mM calcium retained 90-95 % membrane potential by 12 h, while 2.6  mM calcium caused progressive loss of function and integrity, approaching levels seen in freeze-thawed controls. Coulter counter measurements revealed more extensive mitochondrial loss across all calcium-treated groups than fluorescence assays alone, suggesting that dye-based methods may underestimate structural damage. Nonetheless, a substantial proportion of mitochondria remained both structurally and functionally intact at physiologically relevant calcium levels. These findings demonstrate that a substantial number of mitochondria can retain membrane potential and structural integrity after exposure to extracellular calcium concentrations approximating those found in blood. This supports the feasibility of intracoronary mitochondrial transplantation and underscores the need for further in vivo studies to optimize survival and efficacy of mitochondria delivered in calcium-rich environments.

Keywords:  Calcium overload; Cardioprotection; Extracellular mitochondria; Intracoronary Delivery; Ischemia-reperfusion injury; Mitochondrial membrane potential; Mitochondrial transplantation

DOI:  https://doi.org/10.1016/j.mito.2025.102098
Cell Commun Signal. 2025 Nov 13. 23(1): 495

Hypoxia-preconditioning human bone marrow-derived mesenchymal stem cells induce high-quality mitochondrial transfer through gap junctions to alleviate ischemia-reperfusion injury in liver graft.

Xinling Luo, Weiqi Zeng, Erfeng Xiong, Ziming Wang, Jingsheng Huang, Meiqi Luo, Zhongxian He, Jinyu Liu, Dongdong Yuan.

   BACKGROUND: Amid the widespread scarcity of donor livers, mitigating ischemia-reperfusion injury (IRI) of liver grafts is vital for ensuring early recovery of post-transplant liver function. Human bone marrow-derived mesenchymal stem cells (hBMSCs) have shown potential in alleviating IRI damage by regulating mitochondrial function. Hypoxia-preconditioning hBMSCs (hypo-hBMSCs) have shown considerable promise in enhancing therapeutic efficacy, yet the underlying mechanism remain to be elucidated. Therefore, this study aims to explore the role of hypo-hBMSCs in alleviating hepatic IRI and uncover their potential mechanisms, with the goal of offering new strategies for the application of hBMSCs in liver protection after transplantation.
METHODS: Initially, we investigated the impact of hypoxia preconditioning on the quality of hBMSCs mitochondria and whether hypo-hBMSCs can alleviate IRI damage in liver grafts by transferring mitochondria. Subsequently, by employing the enhancer RA and the inhibitor Gap26 to modulate the function of gap junctions (GJs) in vivo and in vitro, we confirmed their crucial role in the process of hypo-hBMSCs transferring mitochondria to hepatocytes. Ultimately, through bioinformatics analysis, Co-IP, siRNA and overexpression, we demonstrate that the up-regulated Cx43 and Cx32 in hypo-hBMSCs can form homotypic Cx43-GJs and Cx32-GJs with hepatocytes, thereby enhancing the transfer of mitochondria.
RESULTS: The results indicate that hypoxia preconditioning diminishes superoxides accumulation and elevates the mitochondrial membrane potential by inducing mitophagy in hBMSCs, consequently improving mitochondrial quality. Upon administration via portal vein injection, hypo-hBMSCs significantly mitigate hepatic IRI. Compared with hBMSCs, hypo-hBMSCs are capable of transferring more mitochondria to hepatocytes through GJs. When the function of GJs is modulated by the enhancer RA or the inhibitor Gap26, the efficiency of mitochondrial transfer correspondingly shifts. Further investigation uncovers that hypo-hBMSCs prompts an upsurge in the expression of Cx43 and Cx32 (not Cx26). Nevertheless, these proteins are unable to form heterotypic GJs (Cx43-Cx32-GJs) with hepatocytes; instead, they form homotypic Cx43-GJs and Cx32-GJs, which facilitate the transfer of mitochondria between hypo-hBMSCs and hepatocytes.
CONCLUSION: Hypo-hBMSCs can enhance mitochondrial quality by inducing mitophagy. Meanwhile, they can up-regulate Cx43 and Cx32 to form homotypic Cx43-GJs and Cx32-GJs with hepatocytes, thereby transferring more high-quality mitochondria to hepatocytes to exert a protective effect.

Keywords:  Gap junctions; HBMSCs; Hepatic ischemia-reperfusion injury; Hypoxia preconditioning; Mitochondrial transfer

DOI:  https://doi.org/10.1186/s12964-025-02497-1
Transl Cancer Res. 2025 Oct 31. 14(10): 6330-6347

Integration of single-cell and bulk transcriptomics to explore prognostic and immunotherapeutic characteristics of sodium overload-induced cell death in lung adenocarcinoma.

Yilun Shi, Xiangyu Qu, Dayu Liu, Huihong Zhang, Suchen Wang, Jiarui Song, Li Wang, Wenrui Wang.

   Background: Recent studies have identified a novel cell death mechanism, termed sodium death, triggered by sustained activation of TRPM4 ion channels. Prolonged TRPM4 channel activity results in excessive sodium ion influx and membrane depolarization, ultimately inducing necrotic cell death. However, the role of sodium death-associated genes (NECSOs) in lung adenocarcinoma (LUAD) remains poorly understood. We used NECSOs to construct a prognostic model of LUAD for prognostic prediction and to explore the features of sodium overload-induced cell death in single cells.
Methods: This study conducted a comprehensive analysis of The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases to investigate TRPM4, a NECSO identified in the literature. Through co-expression analysis, 40 NECSOs were identified. Using the AddModuleScore enrichment algorithm, sodium death scores were calculated for distinct cell clusters and categorized into high- and low-score groups. Differentially expressed genes (DEGs) between these groups were subjected to weighted gene co-expression network analysis (WGCNA) to identify gene modules associated with LUAD. Subsequent differential expression and univariate Cox regression analyses were performed on genes within these modules. Consensus clustering analysis was employed to characterize molecular subtypes, while least absolute shrinkage and selection operator (LASSO) regression was used to develop a prognostic model based on NECSOs. Multiple immune infiltration scoring algorithms and cellular communication analyses were applied to evaluate the relationship between sodium overload (NECSO) and the tumor microenvironment (TME), with the aim of identifying potential therapeutic targets for LUAD.
Results: Single-cell and bulk transcriptome analyses identified 126 NECSOs, of which 28 were differentially expressed between tumor and normal tissues. Among these, 14 genes were significantly associated with overall survival (OS). Pseudotime analysis of epithelial cells revealed that risk-associated genes were predominantly upregulated in later stages, whereas protective genes exhibited reduced expression over time. Eight genes were selected to construct a prognostic signature for NECSOs. Patients in the low-NECSOs group demonstrated significantly better prognosis compared to those in the high-NECSOs group. Cellular communication analysis indicated that epithelial cells with elevated NECSOs expression exhibited enhanced activity in the epidermal growth factor (EGF), Midkine (MK), and COMPLEMENT signaling pathways.
Conclusions: The prognostic model developed from NECSOs enables robust survival prediction for LUAD patients and provides insights into the immune landscape of LUAD. Notably, epithelial cells with higher NECSOs scores displayed a greater propensity for transformation into tumor cells, highlighting their potential as therapeutic targets.

Keywords:  Lung adenocarcinoma (LUAD); immune infiltration; prognostic model; single-cell analysis; sodium overload (NECSO)

DOI:  https://doi.org/10.21037/tcr-2025-919