Search Results (197)

The p53 tumor suppressor, a key transcription factor, acts as a cellular stress sensor that regulates hundreds of genes involved in responses to DNA damage, oxidative stress, and ischemia. Through these actions, p53 can arrest cell cycle, initiate DNA repair, or trigger cell death. In addition to its nuclear functions, p53 can translocate to mitochondria to promote apoptosis. Studies using isolated mitochondria have suggested that p53 drives the voltage-dependent anion channel (VDAC1) into high molecular mass complexes to mediate apoptosis. VDAC1 is a central regulator of cellular energy production and metabolism and also an essential player in apoptosis, induced by various apoptotic stimuli and stress conditions. We previously demonstrated that VDAC1 oligomerization, induced by various apoptosis stimuli and stress conditions, forms a large pore that enables cytochrome c release from mitochondria, thereby promoting apoptotic cell death. In this study, we show that p53 interacts with VDAC1, modulates its expression levels, and promotes VDAC1 oligomerization-dependent apoptosis. Using purified proteins, we found that p53 directly binds VDAC1, as revealed by microscale thermophoresis and by experiments using bilayer-reconstituted VDAC1, in which p53 reduced VDAC1 channel conductance. Furthermore, overexpression of p53 in p53-null cells or in cells expressing wild-type p53 increased VDAC1 expression and induced VDAC1 oligomerization even in the absence of apoptotic stimuli. Together, these findings identify VDAC1 as a direct p53 target whose expression, oligomerization, and pro-apoptotic activity are regulated by p53. They also reinforce the central role of VDAC1 oligomerization in apoptosis. Full article

Background/Objectives: In all types of diabetes, elevated blood glucose levels cause pathological changes in skeletal muscle, primarily due to oxidative stress, mitochondrial dysfunction, and excessive production of reactive oxygen species (ROS). Regular exercise can help mitigate these effects; however, the underlying mechanisms, particularly those involving the mitochondrial permeability transition pore (mPTP), remain incompletely understood. This study aimed to explore the effects of aerobic exercise training (AET) on oxidative stress and the expression of mPTP components in the skeletal muscle of streptozotocin-induced diabetic rats. Methods: Male Wistar rats were randomly divided into three groups: Healthy Sedentary (H-SED), Diabetic Sedentary (D-SED), and Diabetic Exercise-trained (D-EXER); n = 6 per group. The D-EXER group performed AET (0° slope) 5 days/week for 8 weeks. After the intervention period, body weight and fasting blood glucose (FBG) levels were measured, and soleus muscles were collected and analyzed for oxidative stress biomarkers, Western blotting, and gene expression using qRT-PCR. Results: Following an 8-week intervention, AET reduced FBG concentrations. Accordingly, in the soleus muscles of the D-EXER group, ROS levels decreased, and redox balance was improved compared to the D-SED group. Exercise training reduced CypD and Casp9 mRNA expression and increased Bcl-2 mRNA expression, whereas Ant1 mRNA expression was only slightly altered. CypD protein expression was decreased in exercised diabetic rats, while VDAC1 protein and mRNA levels remained unchanged. In the D-EXER group, there were significant inverse correlations between CypD and Casp9 mRNA expression levels and glutathione redox state. Conclusions: The current study suggests that 8 weeks of AET, in addition to reducing hyperglycemia, may favorably influence oxidative balance and the expression of mPTP-related molecular components in diabetic skeletal muscle. Full article

Background: Cannabidiol (CBD) is a major non-psychoactive phytocannabinoid that exerts multiple biological effects in the body. It has been shown to exert anti-cancer effects in a variety of cancer cells, including acute lymphoblastic leukemia of pre-T cell origin (T-ALL), a highly aggressive hematological malignancy. However, the mechanisms underlying CBD’s anti-cancer effects are not fully understood. Furthermore, cancer cells abundantly express surface CD47, which is a negative regulator of phagocytosis and linked with cell survival/death. Little is known about CBD effects on the expression of CD47 in T-ALL cells. The objectives of this study were to address these issues. Methods: Studies were conducted in vitro using Jurkat cells and human peripheral blood mononuclear cells in different culture conditions, CBD concentrations, and in the presence or absence of different reagents. Results: CBD downregulates CD47 expression and induces apoptosis in Jurkat cells. Similar biological effects of CBD were also observed in primary human CD4⁺ T cells, albeit at reduced levels. The CBD’s effects on CD47 expression and apoptosis were not rescued by a cannabinoid receptor (CBR)-2 agonist, a CBR-2 antagonist, or an anion channel blocker. However, these effects on CD47 expression and apoptosis were significantly rescued by a Voltage-Dependent Anion Channel (VDAC)-1 oligomerization inhibitor. Conclusions: Overall, we conclude that CBD downregulates CD47 expression and induces apoptosis involving VDAC-1 oligomerization. Furthermore, they also suggest that CBD’s pro-apoptotic effects on primary human T cells should also be monitored if it is used as an anti-cancer adjuvant or neo-adjuvant therapeutic in cancer patients. Full article

Neuroinflammation and oxidative stress are key drivers of various ocular diseases. Experimental hypoxia, modeled using cobalt chloride (CoCl₂), induces hypoxia-inducible factor 1-alpha (HIF-1α) stabilization, mitochondrial dysfunction, and excessive reactive oxygen species (ROS) production, primarily via the NADPH oxidase 2 (Nox2)–voltage-gated proton channel Hv1 axis. Although Botulinum neurotoxin type A (BoNT/A) is classically recognized for SNAP-25 cleavage, recent studies suggest broader anti-inflammatory and neuroprotective effects. We evaluated BoNT/A in R28 retinal precursor cells and ex vivo retinal explants subjected to CoCl₂-induced hypoxic stress. BoNT/A pretreatment attenuated CoCl₂-induced upregulation of HIF-1α, Hv1, Nox2, NOD-like receptor protein 3 (NLRP3), COX2, and nuclear factor kappa B (NF-κB), while enhancing protective mediators including suppressor of cytokine signaling 3 (SOCS3), Growth Associated Protein 43 (Gap43), and Syntaxin12. Brn3a expression and retinal architecture were preserved, apoptotic cell death reduced, and glial activation suppressed. Moreover, BoNT/A decreased mitochondrial ROS accumulation, restored voltage-dependent anion channel 1 (VDAC1) distribution, and partially stabilized intracellular pH. These findings indicate that BoNT/A mitigates oxidative stress and inflammation in hypoxia-driven retinal injury, at least in part, via modulation of the Nox2–Hv1–ROS axis, and support its potential as a therapeutic candidate for ocular disorders associated with hypoxia and neuroinflammation. Full article

The cryopreservation and transplantation of germline stem cells (GSCs) have become the key to conserving fish genetic resources and safeguarding species diversity. This study aimed to investigate the effects of post-mortem temperature and time on the preservation of oogonial stem cells (OSCs) in the marine fish Paralichthys olivaceus. OSCs remained viable after fish death, and they remained viable and could be cultured after storage at 19 °C for 15 h and at 4 °C for 24 h. Combined transcriptomic and metabolomic analysis was used to identify the pathways leading to OSC death. Several genes were differentially expressed in the ovarian tissue post-mortem, with the most enriched pathways being ferroptosis, fatty acid metabolism/biosynthesis, glutathione metabolism, citric acid cycle (TCA cycle), and arachidonic acid metabolism signaling pathways. Genes related to ferroptosis, such as vdac2, p53, and slc7a11, as well as metabolites such as adrenic acid and arachidic acid, can serve as reliable biomarkers for evaluating the viability of post-mortem OSCs. These findings provide valuable insights and theoretical support for the effective use of post-mortem GSCs and enhance strategies for germplasm resource conservation in fish. Full article

Background: As a chronic threat to human and animal health, diabetes impairs cognition and synaptic plasticity through mechanisms that remain unresolved. This study aims to explore whether mitochondria-associated endoplasmic reticulum membrane (MAM)-mediated mitochondrial Ca²⁺ overload and endoplasmic reticulum stress plays an important role in high-glucose-induced synaptic plasticity damage in hippocampal neurons. Methods and Results: In diabetic mice, cognitive dysfunction was tightly linked to the synaptic plasticity impairment, manifesting as significant reductions in both mRNA and protein levels of PSD-95, GAP-43, and SYP. Concomitantly, aberrant increases in MAM number and structural alterations, along with pronounced up-regulation of Mfn2, were observed in hippocampal tissue from diabetic mice and cultured hippocampal neurons exposed to high glucose. High glucose also elevated MAM-located Ca²⁺ transporters (IP3R, GRP75, MCU, and VDAC1), provoking mitochondrial Ca²⁺ overload and activating ERS, particularly via the IRE1α pathway. Knockdown of Mfn2 ameliorated these high-glucose-induced MAM abnormalities, suppressed mitochondrial Ca²⁺ overload and ERS, and exerted a protective effect against high-glucose-induced synaptic plasticity damage. Application of the inhibitor MCU-i4 to block Ca²⁺ transport within MAM reduced high-glucose-induced mitochondrial Ca²⁺ overload, relieved ERS, and improved high-glucose-induced synaptic plasticity impairment. Application of the inhibitor 4μ8C to suppress the IRE1α pathway of ERS alleviated mitochondrial Ca²⁺ overload and improved high-glucose-induced synaptic plasticity impairment. Conclusions: High glucose elicits MAM dysregulation, which precipitates reciprocal mitochondrial Ca²⁺ overload and ER stress, jointly driving hippocampal synaptic plasticity impairment. Full article

Laserpitium siler subsp. siculum (Apiaceae) is a Mediterranean plant with a long history of traditional medicinal use. In this study, the chemical composition and anticancer potential of three novel (and one new to the genus) sesquiterpene lactones (SLs) isolated from its roots were investigated. The structural characterization, carried out through NMR and HPLC-MS analyses, identified unique guaianolide-type lactones. The biological activity of these compounds was evaluated in vitro using MDA-MB-231 cells, a triple-negative breast cancer (TNBC) cell line. Cell viability assays demonstrated that all SLs tested reduced TNBC cell viability in a dose- and time-dependent manner, with SL-1 exhibiting the highest cytotoxicity. Light microscopy analyses and acridine orange/ethidium bromide staining confirmed the induction of apoptotic cell death, further supported by Western blot analyses showing caspase-3 activation and PARP-1 cleavage. Additional experiments indicated that SL-1 induced oxidative stress, as evidenced by increased ROS production and upregulation of the levels of the antioxidant enzymes MnSOD and HO-1. Moreover, JC-1 staining and Western blot analyses revealed mitochondrial membrane depolarization as well as a significant reduction in VDAC-1 expression, suggesting mitochondrial dysfunction as a key event in the cytotoxic mechanism. These findings highlight L. siler subsp. siculum as a promising source of bioactive compounds with anticancer potential. The ability of its sesquiterpene lactones to induce oxidative stress and mitochondrial impairment provides new insights into their mode of action, supporting further research into their therapeutic applications for TNBC treatment. Full article

Background/Objectives: Bisphenol AF (BPAF) is a prevalent environmental contaminant with demonstrated metabolic and immunological toxicity. This study aimed to investigate whether VDAC1 (Voltage-Dependent Anion Channel 1) mediates BPAF-induced succinate dysmetabolism and inflammatory responses in macrophages, and to evaluate the therapeutic potential of VDAC1 silencing. Methods: RAW264.7 macrophages were exposed to BPAF (0–2500 nM, 24 h) with or without VDAC1 siRNA transfection. Succinate levels, SDH activity, mitochondrial function (complexes I–V, ATP, membrane potential), and inflammatory markers (TNF-α, IL-6, IL-1β, ROS, MDA) were quantified. A 90-day oral toxicity study in C57BL/6J mice (0–32 mg kg⁻¹) assessed systemic inflammation and hepatic ultrastructure. p38 MAPK/NF-κB signaling was evaluated by Western blot and immunofluorescence. Results: BPAF elevated succinate 2.3-fold and decreased SDH activity by 48%, coinciding with reduced mitochondrial membrane potential and ATP synthesis (p < 0.01). Inflammatory cytokines and ROS were markedly increased. VDAC1 siRNA reversed these perturbations, restored complex II activity, and blunted p38 MAPK/NF-κB activation. In vivo, BPAF dose-dependently increased serum TNF-α, IL-6 and IL-1β, promoted NF-κB nuclear translocation and mitochondrial swelling, without altering body or liver weight; VDAC1 knockdown mitigated these effects. Conclusions: VDAC1 orchestrates BPAF-elicited succinate accumulation and macrophage inflammation via p38 MAPK/NF-κB signaling. Targeted VDAC1 silencing alleviates metabolic and inflammatory injury, offering a promising therapeutic strategy against BPAF-related diseases. Full article

Obstructive nephropathy is a common clinical condition caused by urinary retention. After urine flow is restored, kidney function is recovered. However, the effectiveness of this process can be influenced by many factors, including the age of the patient. In this study, we analyzed the following parameters in young and old rats subjected to a 3-day reversible unilateral ureteral obstruction (R-UUO): AKI severity, renal tissue proliferation and histology, inflammatory and fibrosis marker expression, as well as autophagosomal-lysosomal and mitochondrial function. Compared to old rats, young animals exhibited more pronounced renal tissue proliferation and higher expression of profibrotic markers (Col1a1, Fn1, Tgfb1, MMP2), but diminished expression of pro-inflammatory markers (Il1b, Tnfa, Cd32) in response to R-UUO. Additionally, young rats showed more pronounced activity of autophagy, as indicated by increased beclin-1 levels. R-UUO induced severe damage to the mitochondrial respiratory chain in old animals, as indicated by reduced complex I, IV, cytochrome c, VDAC protein levels, and impaired mitochondrial biogenesis (associated with decreased Pgc1a mRNA expression). Thus, we demonstrated that despite restored urine outflow, kidneys exhibited autophagy activation, inflammatory response, and mitochondrial dysfunction after R-UUO. Negative alterations in the kidney were age-dependent indicating necessity for therapeutic strategies optimization for patients of different ages. Full article

Tau protein misfolding and aggregation are central to Tauopathies, yet the temporal dynamics of Tau interactions in vivo remain poorly understood. Here, we applied quantitative proteomics to demonstrate that the interactome of human Tau in adult Drosophila brains changes dynamically over a 12-day time course, revealing a progressive shift from early cytosolic and ribosomal associations to late enrichment of mitochondrial and synaptic partners. Notably, the mitochondrial pore protein Porin/VDAC1 was identified as a late-stage interactor and functional analyses demonstrated that Tau overexpression impairs mitochondrial respiration, elevates oxidative damage, and disrupts carbohydrate homeostasis. To validate this temporally specific interaction, Porin was downregulated, resulting in reduced Tau mitochondrial association, phosphorylation and aggregation. Paradoxically, however, Porin attenuation exacerbated Tau-induced toxicity, including shortened lifespan, locomotor deficits, and impaired learning. These findings indicate that while Porin facilitates pathological Tau modifications, it is also essential for neuronal resilience, highlighting a complex role in modulating Tau toxicity. Our study provides a temporal map of Tau-associated proteome changes in vivo and identifies mitochondria as critical mediators of Tau-driven neurodegeneration. Full article

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