Search Results (187)

Duchenne muscular dystrophy (DMD) is a severe X-linked recessive disorder caused by mutations in the DMD gene, leading to progressive muscle degeneration and fibrosis. A key pathological feature of DMD is mitochondrial dysfunction driven by calcium overload, which disrupts oxidative phosphorylation and triggers cell death pathways. This study shows the therapeutic potential of VBIT-4, a novel inhibitor of the mitochondrial voltage-dependent anion channel (VDAC), in two dystrophin-deficient mouse models: the mild mdx and the severe D2.DMDel8-34 strains. VBIT-4 administration (20 mg/kg) reduced mitochondrial calcium overload, enhanced resistance to permeability transition pore induction, and improved mitochondrial ultrastructure in D2.DMDel8-34 mice, while showing negligible effects in mdx mice. VBIT-4 suppressed mitochondrial and total calpain activity and reduced endoplasmic reticulum stress markers, suggesting a role in mitigating proteotoxic stress. However, it did not restore oxidative phosphorylation or reduce oxidative stress. Functional assays revealed limited improvements in muscle strength and fibrosis reduction, exclusively in the severe model. These findings underscore VDAC as a promising target for severe DMD and highlight the critical role of mitochondrial calcium homeostasis in DMD progression. Full article

Mitochondria-associated membranes (MAMs) are essential for cellular homeostasis. MAMs are specialized contact sites located between the endoplasmic reticulum (ER) and mitochondria and control apoptotic pathways, lipid metabolism, autophagy initiation, and calcium signaling, processes critical to the survival and function of neurons. Although this area of membrane biology remains understudied, increasing evidence links MAM dysfunction to the etiology of major neurodegenerative diseases, such as Alzheimer’s disease, Parkinson’s disease, and amyotrophic lateral sclerosis (ALS). MAMs consist of a network of protein complexes that mediate molecular exchange and ER–mitochondria tethering. MAMs regulate lipid flow in the brain, including phosphatidylserine and cholesterol; disruption of this process causes membrane instability and impaired synaptic function. Inositol 1,4,5-trisphosphate receptor—voltage-dependent anion channel 1 (IP3R-VDAC1) interactions at MAMs maintain calcium homeostasis, which is required for mitochondria to produce ATP; dysregulation promotes oxidative stress and neuronal death. An effective therapeutic approach for altering neurodegenerative processes is to restore the functional integrity of MAMs. Improving cell-to-cell interactions and modulating MAM-associated proteins may contribute to the restoration of calcium homeostasis and lipid metabolism, both of which are key for neuronal protection. MAMs significantly contribute to the progression of neurodegenerative diseases, making them promising targets for future therapeutic research. This review emphasizes the increasing importance of MAMs in the study of neurodegeneration and their potential as novel targets for membrane-based therapeutic interventions. Full article

Male infertility affects 8–12% of couples worldwide and is solely responsible in up to 30% of cases. Assisted Reproductive Technologies (ARTs) provide potential solutions, particularly in conditions where spermatozoa display structural abnormalities or impaired motility, such as asthenozoospermia. Sperm metabolism demonstrates remarkable flexibility, shifting between glycolysis and oxidative phosphorylation to produce ATP required for motility. Glycerol kinase 2 (GK2) phosphorylates glycerol in the sperm midpiece, generating glycerol-3-phosphate, a key intermediate in glycolysis, lipid metabolism, and oxidative phosphorylation. The localization of GK2 suggests not only a regulatory role in sperm metabolism but also a possible association with VDAC proteins, contributing to ADP-ATP exchange between the cytosol and mitochondria. Elucidating the role of GK2 in spermatozoa is of particular relevance, as this enzyme not only contributes to key metabolic pathways but may also interact with VDAC proteins, influencing mitochondrial function and energy exchange. Such interactions could play a pivotal role in regulating sperm motility. A deeper understanding of these mechanisms could position GK2 as a valuable biomarker: in scenarios where GK2–VDAC interactions are confirmed, it may guide optimized sperm selection methods in ARTs, whereas the absence or impairment of such interactions could serve as a diagnostic indicator in asthenozoospermic men. Full article

Chlorpyrifos (CPF), an organophosphate pesticide, is known to induce pulmonary toxicity through oxidative stress, mitochondrial dysfunction, and inflammation. Astaxanthin (ASX), a xanthophyll carotenoid derived primarily from marine microalgae (Haematococcus pluvialis), possesses strong antioxidant properties and has demonstrated cellular protective effects in numerous oxidative stress studies. However, its efficacy against CPF-induced lung cell damage remains uncharacterized. This study revealed the protective role of ASX, as a pretreatment and co-treatment, against CPF-induced cytotoxicity in human A549 lung adenocarcinoma cells by assessing cell viability, intracellular reactive oxygen species (IROS), total oxidative status (TOS), total antioxidant capacity (TAC), mitochondrial membrane potential (MMP), intracellular calcium ions (Ca²⁺), lactate dehydrogenase (LDH) release, malondialdehyde (MDA) levels, glutathione peroxidase (GPx) activity, superoxide dismutase (SOD) activity, DNA fragmentation, and apoptosis/inflammation-associated gene expression. CPF treatment significantly decreased cell viability and TAC, while elevating IROS, TOS, MMP, intracellular Ca²⁺, and LDH release. CPF also increased MDA levels and suppressed GPx and SOD activities. DNA fragmentation and quantitative polymerase chain reaction (qPCR) analysis revealed upregulation of pro-apoptotic and inflammatory markers such as BCL2-associated X protein (BAX), caspase-3 (CASP3), tumor protein p53 (TP53), tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), nuclear factor kappa B (NFκB), and voltage-dependent anion-selective channel protein 1 (VDAC1) and suppression of anti-apoptotic B-cell lymphoma 2 (BCL2) and antioxidant defense genes nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1). ASX treatment, particularly when administered as a pretreatment, significantly reversed CPF-induced oxidative and inflammatory responses by restoring SOD, GPx, and TAC levels, reducing IROS, TOS, MDA, and LDH release, and downregulating apoptotic and inflammatory gene expressions. ASX pretreatment notably decreased MMP and intracellular Ca²⁺ levels, indicating protection against mitochondrial dysfunction and calcium dysregulation. ASX upregulated Nrf2 and HO-1 expression and restored the BCL2/BAX balance, suggesting inhibition of mitochondrial-mediated apoptosis. Additionally, ASX significantly attenuated CPF-induced anti-angiogenic effects in the in ovo Hen’s Egg Test Chorioallantoic Membrane (HET-CAM) assay. These findings demonstrate, for the first time, that ASX exerts a broad spectrum of protective effects against CPF-induced cytotoxicity in lung cells, mainly through the stabilization of mitochondrial redox status and modulation of apoptosis- and inflammation-related gene pathways, highlighting ASX as a promising candidate for further therapeutic development. Furthermore, the pronounced efficacy observed in the pretreatment regimen suggests that ASX can be evaluated as a potential nutritional preventive strategy in high-risk populations with occupational or environmental CPF exposure. Full article

Soybean (Glycine max L.) is grown worldwide to obtain edible oil, livestock feed, and biodiesel. However, drought and salt stress are becoming serious challenges to global soybean cultivation as they retard the growth of soybean plants and cause significant yield losses. Voltage-dependent anion-selective channel (VDAC) proteins are well-known for their role in drought and salt tolerance in crop plants. In this study, we identified 111 putative VDAC genes randomly distributed in genomes of 14 plant species, including cultivated soybean (Glycine max) and wild soybean (Glycine soja). The comparative phylogenetic studies classified these genes into six different clades and found the highest structural similarities among VDAC genes of G. max and G. soja. From the conserved domain database, porin-3 (PF01459) was found to be the conserved domain in all VDAC proteins. Furthermore, gene annotation studies revealed the role of GmaVDAC proteins in voltage-gated anion channel activity. These proteins were also found to interact with other proteins, especially mitochondrial receptors. A total of 103 miRNAs were predicted to target fifteen GmaVDAC genes. In G. max, these genes were found to be segmentally duplicated and randomly distributed on twelve chromosomes. Transcriptomic analysis revealed that the GmaVDAC18.2 gene showed overexpression in root nodules, whereas the GmaVDAC9.1, GmaVDAC18.1, and GmaVDAC18.2 genes showed overexpression under drought and salt stress conditions. Full article

Hexokinase catalyzes the first rate-limiting step glycolysis. However, the roles of hexokinase 2 (HK2) in asthma remain incompletely understood. This study aimed to investigate metabolic alterations in asthma, focusing on the expression, function and regulation of HK2. In this study, non-targeted metabolomics analysis of 20 asthma patients and 15 healthy controls identified metabolic alterations in asthma, particularly in the glycolytic pathways. Consistently, HK2 expression was elevated in both asthma individuals and mice with allergic airway inflammation. Airway epithelium–specific HK2 knockdown and pharmacological inhibition with 2-deoxy-D-glucose (2-DG) significantly attenuated airway inflammation and hyperresponsiveness in mice induced by ovalbumin/ lipopolysaccharide. Mechanistic analyses demonstrated that HK2 regulates epithelial apoptosis and inflammation via interaction with peptidylprolyl isomerase F (PPIF), independent of voltage-dependent anion channel 1 (VDAC1). Asthma is associated with metabolic reprogramming, characterized by alterations in lipid and glucose metabolism. These findings establish HK2 plays a crucial role in asthma pathogenesis by promoting airway epithelial apoptosis and inflammation in asthma, suggesting its potential as a therapeutic target. Full article

The family of voltage-dependent anion channels (VDACs) comprises three isoforms (VDAC-1, VDAC-2, VDAC-3). VDACs have been extensively described as localised in the outer mitochondrial membrane where they are involved in the exchange of ions, metabolites, and ATP/ADP between mitochondria and cytosol. The VDAC interacts with disease-specific proteins and thus regulates the mitochondrial function and controls the cellular energy resources, explaining its involvement in cell death and apoptosis. In addition, VDAC-1 and -2 can also be found at other cellular locations such as in the sarcoplasmic reticulum, in the endoplasmic reticulum, as well as in the plasma membrane. Through single-channel pore regulation, oligomerisation, or changed expression levels the VDAC is involved in different neurodegenerative diseases such as Alzheimer’s disease, Parkinson’s disease, Amyotrophic lateral sclerosis, Huntington’s disease, and others. Here, we critically summarise current discussions about the VDAC as a common key player for these diseases. We suggest that the VDAC acts as a transmembrane multifunctional regulatory protein which might serve as a pharmacological target for the development of novel drugs against neurodegenerative diseases such as the application of recombinant antibody technology. Full article

Background/Objectives: Traumatic brain injury (TBI) remains a significant and urgent medical concern for the US military. TBI triggers excitotoxic responses immediately, involving mitochondrial dysfunction characterized by loss of calcium (Ca²⁺) cycling, membrane damage and increased cell death. However, a comprehensive understanding of mitochondria-centric excitotoxic responses over time has yet to be fully demonstrated after severe TBI. The current study evaluated mitochondria-centric time course responses between 30 min and 2 weeks (seven time points) after penetrating TBI (pTBI). Methods: Anesthetized adult male Sprague-Dawley rats were subjected to either 10% unilateral pTBI or Sham craniectomy. Animals were euthanized at various time points, and mitochondria were isolated from the injury core. Results: Post-injury mitochondrial Ca²⁺ homeostasis was significantly compromised in pTBI compared to the Sham group. In parallel, mitochondrial membrane integrity markers, including cytochrome c (Cyt C) and voltage-dependent anion channel (VDAC), showed significant reduction over time post-pTBI. Apoptosis-responsive markers, such as glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and B-cell lymphoma 2 (Bcl-2), exhibited elevated responses over time post-pTBI. Conclusions: Our results demonstrate profound insights into elevated excitotoxic mitochondrial damage after severe TBI. This time course study uncovers novel mitochondrial targets involved in TBI excitotoxicity and offers mitigation opportunities to alleviate excitotoxic responses after penetrating TBI. Full article

Background: The limited regenerative capacity of adult mammalian cardiomyocytes (CMs) poses a significant challenge for cardiac repair following myocardial infarction. In contrast to adult mammals, CMs in zebrafish and newt hearts retain a lifelong capacity for proliferation and cardiac regeneration. Likewise, neonatal mice exhibit a brief postnatal period, during which CMs retain the ability to proliferate and contribute to myocardial repair, which markedly diminishes within the first week of life. Emerging evidence indicates that adult CM cell cycle progression is critically influenced by oxidative stress. Adult mammalian CMs possess a high mitochondrial content to meet their substantial energy demands. However, this also leads to elevated reactive oxygen species (ROS) production, resulting in DNA damage and subsequent cell cycle arrest. We hypothesize that reducing the mitochondrial content in adult CMs will mitigate ROS production, thereby facilitating cell cycle progression. Methods: Adult CMs were isolated from adult rats (≥12 weeks old). To induce mitophagy, adult CMs were transfected with parkin-expressing plasmid and then treated with carbonyl cyanide 3-chlorophenylhydrazone (CCCP), a mitochondrial protonophore, for 7 days. Post-treatment assessments included the quantification of adult CM proliferation, mitochondrial content, and ROS levels. Results: CCCP-treated adult CMs exhibited a significant increase in proliferation markers, including EdU incorporation, KI67, phospho-histone H3, and Aurora B. Furthermore, CCCP treatment significantly reduced the mitochondrial content, as evidenced by decreased MitoTracker, TMRM, and Tom20 staining compared to controls. This was accompanied by electron microscopy analysis, which showed a significant reduction in the mitochondrial number in the adult CM after CCCP treatment. Moreover, our results also demonstrate a marked reduction in oxidative stress, demonstrated by lower 123-dihydro-rhodamine (123-DHR), CellROX signals, and VDAC. Conclusions: Our findings demonstrate that CCCP-mediated mitochondrial depletion reduces oxidative stress and promotes cell cycle re-entry in adult CM. This study provides direct experimental evidence and substantiates the role of elevated mitochondria and ROS levels in adult CM cell cycle exit. Full article

Hair follicle stem cells (HFSCs) are pluripotent stem cells located in the bulges of hair follicles. Apoptosis regulates tissue homeostasis by eliminating unnecessary or damaged cells during development and aging. VDAC2, located in the outer mitochondrial membrane (MOM), is a key apoptosis regulator, but its role in cashmere goat hair follicles remains unclear. In previous studies, through proteomic sequencing, we found that VDAC2 was significantly differentially expressed in the anagen, catagen, and telogen phases of the hair follicles of Albas cashmere goats. This study aimed to explore the role of VDAC2 in secondary hair follicle stem cells (SHFSCs) and preliminarily investigate its regulatory mechanism through RNA-seq. Overexpression of VDAC2 promoted apoptosis in SHFSCs, while knockdown had the opposite effect. RNA-seq analysis, together with expression validation of downstream genes, indicates that the P53 signaling pathway may be involved in VDAC2-mediated SHFSC regulation. RT-qPCR and Western blotting confirmed that VDAC2 activated the P53 signaling pathway in SHFSCs. Furthermore, the use of a P53 inhibitor after VDAC2 overexpression partially rescued the apoptosis of cells caused by VDAC2. These results demonstrate that VDAC2 plays an important role in SHFSC apoptosis. Our findings greatly enhance our understanding of the role of VDAC2 in SHFSC apoptosis and hair follicle growth. Full article

Background: Besides diabetes mellitus, metformin has been identified as a potential therapeutic agent for treating various other conditions that include various cancers, cardiovascular diseases, neurodegenerative diseases, and aging. In cancer, metformin increased apoptotic cell death, while inhibiting it in neurodegenerative diseases. Thus, different modes of metformin action at the molecular level have been proposed. Methods: In this study, we present the mitochondria and the VDAC1 (voltage-dependent anion channel) as a potential target of metformin. Results: Metformin induces VDAC1 overexpression, its oligomerization, and subsequent apoptosis. Metformin analogs phenformin and buformin at much lower concentrations also induce VDAC1 overexpression, oligomerization, and cell death. We demonstrate the interaction of metformin with purified VDAC1, which inhibited its channel conduction in a voltage-dependent manner. Metformin bound to the synthetic VDAC1-N-terminal peptide and binding to this domain was also found by its molecular docking with VDAC1. Moreover, we demonstrated metformin binding to purified hexokinases (HK-I) with a 400-fold lower metformin concentration than that required for cell death induction. In cells, metformin induced HK-I detachment from the mitochondrial VDAC1. Lastly, metformin increased the expression of NLRP3 and ASC and induced their co-localization, suggesting inflammasome activation. Conclusions: The results suggest that VDAC1 is a target for metformin and its analogs, and this is associated with metformin’s adverse effects on many diseases. Full article

Type 1 diabetes (T1D) is a chronic metabolic disease defined by sustained hyperglycemia, leading to oxidative stress (OS) and systemic complications, including male subfertility. This study investigates the potential impact of T1D-induced OS on microtubule (MTs) dynamics and microtubule-associated proteins (MAPs) in the testis and spermatozoa (SPZ). Using a streptozotocin-induced T1D rat model, we examined the expression and localization of key MAPs, including Microtubule Affinity-Regulating Kinase 4 (MARK4), Microtubule-Associated Protein 1A (MAP1A), Dynein Light Chain LC8-Type 1 (DYNLL1), Prolyl Endopeptidase (PREP), and Radial Spoke Head 6 Homolog A (RSPH6A), alongside sperm functional parameters. Our findings showed that T1D significantly impaired the expression and distribution of these proteins, which may affect MTs organization and be associated with cytoskeletal disorganization, and impaired germ cell differentiation. Moreover, T1D rats exhibited reduced sperm count, viability, and motility, accompanied by increased DNA fragmentation and chromatin defects. Elevated levels of 4-hydroxy-2-nonenal (4-HNE), a marker of OS, were detected in SPZ, particularly in the acrosome and flagellum, correlating with mitochondrial dysfunction and ATP depletion. Additionally, decreased intracellular Ca²⁺ levels, downregulation of Cation Channel of Sperm (CATSPER) and Voltage-Dependent Anion Channel 3 (VDAC3), and altered tubulin acetylation, possibly due to imbalanced Alpha-Tubulin N-Acetyltransferase 1 (ATAT1) and Histone Deacetylase 6 (HDAC6) expression, were also associated with impaired sperm motility. The combined data suggest that T1D-induced OS is linked to disrupted MTs dynamics, which may contribute to testicular dysfunction and reduced sperm quality, potentially affecting male fertility. A better understanding of these associations may support the development of therapeutic strategies to mitigate the reproductive consequences of T1D and improve male fertility outcomes. Full article

Resveratrol is a naturally occurring phenolic compound found in various foods such as red wine, chocolate, peanuts, and blueberries. Both in-vitro and in-vivo studies have shown that it has a broad spectrum of pharmacological effects such as providing cellular protection and promoting longevity. These effects include antioxidant, anti-inflammatory, neuroprotective, and anti-viral properties, as well as improvements in cardio-metabolic health and anti-aging benefits. Additionally, resveratrol has demonstrated the ability to induce cell death and inhibit tumor growth across different types and stages of cancer. However, the dual effects of resveratrol—acting to support cell survival in some contexts, while inducing cell death in others—is still not fully understood. In this study, we identify a novel target for resveratrol: the voltage-dependent anion channel 1 (VDAC1), a multi-functional outer mitochondrial membrane protein that plays a key role in regulating both cell survival and death. Our findings show that resveratrol increased VDAC1 expression levels and promoted its oligomerization, leading to apoptotic cell death. Additionally, resveratrol elevated intracellular Ca²⁺ levels and enhanced the production of reactive oxygen species (ROS). Resveratrol also induced the detachment of hexokinase I from VDAC1, a key enzyme in metabolism, and regulating apoptosis. When VDAC1 expression was silenced using specific siRNA, resveratrol-induced cell death was significantly reduced, indicating that VDAC1 is essential for its pro-apoptotic effects. Additionally, both resveratrol and its analog, trans-2,3,5,4′-tetrahydroxystilbene-2-O-glucoside (TSG), directly interacted with purified VDAC1, as revealed by microscale thermophoresis, with similar binding affinities. However, unlike resveratrol, TSG did not induce VDAC1 overexpression or apoptosis. These results demonstrate that resveratrol-induced apoptosis is linked to increased VDAC1 expression and its oligomerization. This positions resveratrol not only as a protective agent, but also as a pro-apoptotic compound. Consequently, resveratrol offers a promising therapeutic approach for cancer, with potentially fewer side effects compared to conventional treatments, due to its natural origins in plants and food products. Full article

Oxidative stress (OS) is regarded as a major contributor to granulosa cellapoptosis in ovarian disease. 1-Deoxynojirimycin (1-DNJ), a naturally occurring plant alkaloid, exhibits antioxidant, anti-inflammatory, and metabolism-modulating properties. Mitochondria and endoplasmic reticulum (ER), crucial organelles regulating oxidative balance, interact through mitochondria-associated endoplasmic reticulum membranes (MAMs) for signaling and molecular exchange. However, it remains unclear whether 1-DNJ attenuates oxidative damage in ovarian granulosa cells (GCs) via MAMs-mediated ER–mitochondria crosstalk, which needs further exploration. This study aimed to investigate the mechanisms by which 1-DNJ affects oxidative damage and apoptosis induced by OS in porcine follicular GCs by regulating mitochondrial function, MAMs, and ER interactions. Here, we found that GCs suffered from OS, accompanied by the up-regulation of ROS and MDA, alongside reduced activity of antioxidant enzymes (CAT and T-SOD). Further studies revealed that the up-regulation of MAMs proteins (MFN2, MCU, and VDAC1) and pro-apoptosis proteins (BAX and Cleaved-capase3), along with increased mitochondrial ROS and Ca²⁺ levels, led to the down-regulation of MMP and ATP content. These, in turn, triggered mitochondrial dysfunction, and MAMs destabilization, and subsequent apoptosis. Additionally, the up-regulation of the protein levels of P-PERK/PERK, GRP78, ATF4, and CHOP protein expression activated the PERK-ATF4 signaling pathway, which triggered endoplasmic reticulum stress (ERS). Conversely, 1-DNJ alleviated H₂O₂-induced mitochondrial and MAMs dysfunction and ERS, which in turn attenuated apoptosis. Further, ATF4 knockdown inhibited MFN2 protein expression, which attenuated H₂O₂-induced MMP inhibition, Ca²⁺ overload, ROS production, and mitochondrial damage. In summary, 1-DNJ mitigated OS-induced mitochondrial dysfunction in GCs and regulated ER–mitochondrial communication through MAMs, reducing OS-induced apoptosis. The present study demonstrates that 1-DNJ protects ovarian GCs from OS-induced damage by modulating ER and mitochondrial homeostasis through MAMs, offering new perspectives and a theoretical basis for the treatment of ovarian diseases. Full article

Pore-forming peptides are promising antimicrobial and anticancer agents due to their membrane selectivity and biodegradability. Our prior work identified peptide M159, which permeabilized synthetic phosphatidylcholine liposomes without mammalian cell toxicity. Here, we report that the D-type variant (D-M159) induces apoptosis in HeLa cells under starvation. To explore its anticancer mechanism, we analyzed D-M159 cytotoxicity, intracellular uptake, and apoptotic pathways via flow cytometry, confocal microscopy, and Western blot. Calcium dynamics and mitochondrial function were examined via specific labeling and functional assays. Results revealed that D-M159 exhibited starvation-dependent, dose-responsive cytotoxicity and triggered apoptosis in HeLa cells. Mechanistic studies indicated that D-M159 entered the cells via caveolin-dependent and caveolae-dependent endocytosis pathways and induced endoplasmic reticulum stress in HeLa cells by up-regulating proteins such as ATF6, p-IRE1, PERK, GRP78, and CHOP. Meanwhile, D-M159 promoted the expression of IP3R1, GRP75, and VDAC1, which led to mitochondrial calcium iron overload, decreased mitochondrial membrane potential, and increased reactive oxygen species (ROS) generation, thereby activating the mitochondrial apoptotic pathway and inducing the aberrant expression of Bax, Bcl-2, Caspase-9, and Caspase-3. This study showed that D-M159 synergistically induced apoptosis in starved HeLa cells through endoplasmic reticulum stress and mitochondrial dysfunction, demonstrating its potential as a novel anticancer agent. Full article