Journal of Bioenergetics and Biomembranes最新文献

Clinical evidence points to the Traditional Chinese Medicine Fuzheng Huayu recipe (FZHYR) as an anti-fibrosis drug. Our previous studies have shown that FZHYR regulates macrophage polarization and the expression of NADH dehydrogenase (ubiquinone) 1 alpha subcomplex subunit 2 (NDUFA2) to inhibit pulmonary fibrosis. This study aims to explore the mechanism of FZHYR regulates macrophage polarization and NDUFA2 expression in the treatment of pulmonary fibrosis. NR8383 alveolar macrophages polarizing to M1 or M2 polarization by stimulation with LPS/IFN-γ or IL-14/IL-13 and received FZHYR treatment. Macrophage polarization was verified by detecting the levels of transmembrane protein that specific expression using flow cytometry and levels of inflammatory factors. Oxidative phosphorylation change was reflected by mitochondrial ROS and oxygen consumption rate. The effect of FZHYR on m6A of Ndufa2 mRNA and the involvement of m6A modification enzymes (METTL3 and IGF2BP1) was investigated. FZHYR promoted macrophage M1 polarization and inhibited macrophage M2 polarization. FZHYR inhibited oxidative phosphorylation and NDUFA2 expression in M2 macrophages. Ndufa2 silencing inhibited macrophage M2 polarization and oxidative phosphorylation. M2 macrophage polarization and oxidative phosphorylation induced by Ndufa2 overexpression were reversed by FZHYR. Mechanistically, METTL3 induced Ndufa2 m6A methylation in an IGF2BP1-dependent manner in FZHYR-treated M2 macrophage. Moreover, the inhibition of METTL3 suppressed macrophage M2 polarization and oxidative phosphorylation. FZHYR inhibits M2 macrophage polarization through the inhibition of METTL3-mediated m6A modification and downregulation of NDUFA2 and oxidative phosphorylation.

Heart failure represents the culmination of various cardiovascular diseases, distinguished by a spectrum of complex symptoms. Astragaloside IV (AST-IV) has shown significant cardiac protection in heart failure rats, though the mechanisms are not fully understood. This study aimed to investigate the effects of AST-IV using hypoxia-reoxygenation injury in cardiomyocytes and heart failure in rats to explore the effects of AST-IV. Experimental groups were treated with AST-IV, HIF-2α siRNA, or Y-27,632 (a ROCK inhibitor). Cell proliferation was assessed using CCK-8 and EdU assays, while mitochondrial membrane potential and apoptosis were evaluated using JC-1 fluorescent probes and TUNEL staining, respectively. Additionally, flow cytometry measured reactive oxygen species and apoptosis rates, with protein expressions of HIF-2α, RhoB, and ROCK determined via western blotting. Cardiac troponin I and caspase-3 levels were quantified using ELISA, and myocardial injury was examined through H&E and Masson staining. Results demonstrated that AST-IV notably increased HIF-2α and Rho/ROCK pathway protein expressions, enhancing cell proliferation, reducing apoptosis and ROS levels, but effects were partially reversible by Y-27,632 in vitro. Our findings suggest that AST-IV mitigates hypoxia-induced cardiomyocyte damage by modulating the HIF/Rho/ROCK pathway, indicating its potential as a therapeutic agent for heart failure.

This study investigates the interactions of primary and secondary bile acids (cholic acid (CA), chenodeoxycholic acid (CDCA), ursodeoxycholic acid (UDCA), and lithocholic acid (LCA)) with isolated rat liver mitochondria, focusing on their uncoupling activity, detergent effects, and antioxidant properties. Using a recently developed methodological approach based on quantifying the effective distribution coefficient ([Formula: see text]), we precisely assessed the partitioning of bile acids between the mitochondrial and aqueous phases. Our results demonstrate that the uncoupling potency rank order was LCA > CDCA > CA, which strongly correlated with their lipophilicity. In contrast, UDCA, which possesses hydroxyl groups on the hydrophobic β-surface, exhibited significantly lower uncoupling activity. At concentrations inducing mild uncoupling (stimulating state 4 respiration by 70-75%), all bile acids significantly reduced the ADP/O ratio and respiratory control ratio without inhibiting the electron transport chain, confirming their protonophoric mechanism. Furthermore, we quantitatively showed that bile acids, in contrast to palmitic acid, exert a mild detergent effect, as evidenced by a increase in NADH-stimulated respiration, with UDCA and CA having the most pronounced effect. Crucially, at these uncoupling concentrations, all bile acids consistently suppressed mitochondrial H₂O₂ generation by 30-40%, revealing their antioxidant potential. These findings provide quantitative insights into the structure-dependent dual roles of bile acids in modulating mitochondrial function.

According to reports, Rab3A plays a kay role in various diseases. The regulatory role of Rab3A in hair cell damage and age-related hearing loss has not been explored. HEI-OC-1 cells were treated with hydrogen peroxide (H₂O₂) to construct a damage model. The cell viability and apoptosis were detected by CCK-8 assay and flow cytometry. Immunofluorescence and flow cytometry were used to measure mitochondrial membrane potential. The contents of oxidative stress-related indicators and mitochondrial function-related indicators were detected by kits. Dual luciferase assay was used to determine the regulatory relationship between Rab3A and ITGA3. The results showed that H₂O₂ treatment reduced the level of Rab3A in HEI-OC-1 cells in a time-dependent manner. Rab3A increased the cell viability of H₂O₂-induced inner ear cells and inhibited cell apoptosis. Additionally, Rab3A inhibited H₂O₂-induced oxidative stress and alleviated mitochondrial dysfunction in HEI-OC-1 cells. Rab3A also directly targeted and positively regulated ITGA3 expression. Further studies found that silencing of ITGA3 reversed the inhibitory effects of Rab3A on inner ear cell damage and mitochondrial dysfunction. In conclusion, Rab3A regulates H₂O₂-induced inner ear hair cell damage and mitochondrial dysfunction by stabilizing the expression of ITGA3.

The cardioprotective effects of sodium-glucose cotransporter-2 inhibitors (SGLT2i) have attracted significant attention. The calcium ion signaling pathway influences various aspects of cellular function, store-operated calcium channels (SOCCs) serve as key calcium ion channels that induce cell apoptosis and exacerbate cardiac remodeling. This study aims to investigate the effects of SGLT2i on SOCCs and its potential cardioprotective mechanisms. Sprague-Dawley (SD) rats were sequentially treated with angiotensin II (Ang II) and dapagliflozin (Dapa), randomly divided into four groups: Sham, Dapa, Ang II, and Ang II + Dapa. Blood pressure, cardiac structure and function were measured. Cardiac fibrosis evaluated using Masson's trichrome staining. The apoptosis rate of H9C2 cells was determined by flow cytometry. Protein expression levels and functional activity of SOCCs were analyzed using Western blotting, calcium imaging, and fluorescence co-localization staining. In Ang II-induced hypertension rats, no significant blood pressure lowering effect of Dapa was observed within 28 days. Notably, the absence of blood pressure reduction did not affect the timely improvement of Ang II-induced cardiac remodeling by Dapa. Ang II enhanced store-operated calcium entry (SOCE), subsequently promoting cardiomyocyte apoptosis. Dapa administration effectively suppressed this pathological process by inhibiting the overexpression and overactivation of SOCC. SGLT2i improved early cardiac remodeling induced by Ang II without relying on antihypertensive effects, mainly by inhibiting excessive activation of SOCE, which effectively attenuated Ang II-triggered cardiomyocyte apoptosis. This provides a novel therapeutic paradigm targeting impaired myocardial calcium handling in hypertensive heart disease management.

Acute myeloid leukemia is a life-threaten disease. Researches have indicated that increased expression of TKT was closely related to the progression of malignant tumors. However, the mechanism of TKT in the pathogenesis of AML need to be further elucidated. Here, we showed that the expression levels of TKT was increased in AML patients and AML cells. TKT overexpression in AML cells significantly promoted the proliferation, migration and invasion of cells while TKT knockdown had opposite effects. Mechanistically. We proved that TKT was located on up-stream of RBKS and TKT promoted the growth of AML cells through RBKS. In addition, our data indicated that TKT regulates the pentose phosphate pathway via RBKS. Notably, we demonstrated that the pentose phosphate pathway is crucial for EMT program in AML cells. Taken together, this study identified the molecular mechanism by which TKT promotes AML progression, namely, TKT promotes EMT by regulating the pentose phosphate pathway through RBKS. Our results suggest that TKT maybe a novel therapeutic target for AML treatment.

Pholiota adiposa is a traditional Chinese medicine "Huangsan". Huangsan is rich in proteins, polysaccharides, which has been documented to be used in the treatment of cancer. However, the pharmacological mechanism of Huangsan in the treatment of cancer remains unclear. This research examined the anticancer mechanisms of the ethanol extract of P. adiposa (EPA) in hepatoma-bearing mice via metabolomic analysis. Male ICR mice were randomly assigned to the control (CG), model (MG), positive (25 mg/kg/day cyclophosphamide; PG), low-level EPA (LG, 100 mg/kg/day), and high-level EPA (HG, 300 mg/kg/day) groups. Various biochemical indicators were assessed via enzyme-linked immunosorbent assay, TdT-mediated dUTP nick-end labeling assay, and hematoxylin and eosin staining. Western blot was utilized to assess tumor apoptosis-related caspase-3, cleaved caspase-3, Bcl-2, Bcl-2-associated X, and vascular endothelial growth factor. Ultra-performance liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry and chemometric approaches were applied to determine serum metabolomics. EPA substantially impacted tumor growth in vivo without causing adverse reactions, indicating liver and kidney protection. EPA significantly increased the levels of glutamine, leucine, histidine, citrulline, creatine, prostaglandin A2, and prostaglandin D2 while decreasing levels of arachidonic acid, 20-hydroxyeicosatetraenoic acid, thromboxane B2, and pyruvate. These changes reflected a reduction in protein digestion and absorption, alterations in γ-aminobutyric acid metabolism, and shifts in amino acid metabolism, particularly affecting arachidonic acid, arginine, and proline. EPA exerted significant anticancer effects in mice mainly by reducing the compensatory energy supply from branched-chain amino acids, regulating amino acid metabolism, inhibiting negative nitrogen balance, enhancing immune responses, inhibiting inflammatory mediators, and promoting tumor cell apoptosis in the tumor microenvironment.

Abdominal aortic aneurysm (AAA) is a life-threatening vascular disease characterized by aortic wall degeneration and inflammation. The molecular mechanisms underlying AAA development remain unclear. Wilms tumor 1-associated protein (WTAP) has been implicated in various biological processes, but its role in AAA pathogenesis, particularly in cardiomyocyte regulation, has not been fully explored. Quantitative real-time PCR (qRT-PCR) was performed to detect the mRNA levels of WTAP and proprotein convertase subtilisin/kexin type 9 (PCSK9). Western blotting assay was used to analyze protein expression. Cell viability, proliferation, senescence, apoptosis, ferroptosis, and inflammation were assessed using cell counting kit-8 assay, 5-Ethynyl-2'-deoxyuridine assay, SA-β-gal staining, flow cytometry, fluorometric assay, colorimetric method, and enzyme-linked immunosorbent assay. The association among PCSK9, WTAP, and IGF2BP2 was analyzed using RNA immunoprecipitation assay and dual-luciferase reporter assay. WTAP expression was upregulated in AAA and angiotensin II (Ang II)-induced human aortic smooth muscle cells (HASMCs). Ang II treatment inhibited HASMC proliferation and induced senescence, apoptosis, ferroptosis, and NLRP3 inflammasome-mediated inflammation. However, these effects were mitigated by WTAP knockdown. In addition, PCSK9 expression was increased in AAA, and WTAP stabilized PCSK9 mRNA expression in an IGF2BP2-dependent manner. Moreover, WTAP overexpression promoted senescence, apoptosis, ferroptosis, and inflammation by regulating PCSK9 in Ang II-induced HASMCs. WTAP silencing protected HASMCs from Ang II-induced senescence, apoptosis, ferroptosis, and inflammation by regulating PCSK9, suggesting a potential therapeutic target for AAA treatment.

Retinoblastoma (RB) is a malignant neoplasm originating from photoreceptor precursor cells that is common in children under 3 years of age. NOP2/Sun RNA methyltransferase family member 2 (NSUN2) is a major methyltransferase that catalyzes mammalian mRNA 5-methylcytosine (m5C) modification and has been implicated in a variety of diseases, but its mechanism in RB is still incomplete. NSUN2 was up-regulated in RB and was associated with the poor survival of patients. Silencing NSUN2 blocked the malignant behaviors of RB cells. In Y79 cells, the differentially expressed genes (DEGs) after knocking down NSUN2 were mainly concentrated in the glycolytic pathway from the GSE214685 dataset, and NSUN2 down-regulation restrained the glycolysis of RB cells. What's more, the m5C modification and mRNA stability of hexokinase domain component 1 (HKDC1) were mediated by NSUN2 and Y-box binding protein 1 (YBX1). Mechanically, NSUN2 promoted RB malignant behaviors and glycolysis in vitro via HKDC1 and accelerated tumor growth in vivo. Our study put forward a new mechanism to regulate RB progression, namely, NSUN2 and YBX1 synergistically promote malignant progression and glycolysis of RB by mediating HKDC1 m5C modification.

The precise pathogenic mechanisms underlying sepsis-induced acute respiratory distress syndrome (ARDS) remain incompletely characterized. Emerging evidence implicates ferroptosis of alveolar epithelial cells in ARDS pathogenesis, though the regulatory networks governing this association require further elucidation. Stimulator of interferon genes (STING), conventionally recognized as a pivotal mediator of innate immunity through DNA-sensing pathways, has recently been linked to ferroptosis. This investigation elucidates the pulmonary protective mechanisms of DMF in sepsis-induced ALI models. Experimental data revealed elevated ferroptotic activity, inflammatory markers, and oxidative stress in lungs following cecal ligation and puncture (CLP) procedures. DMF administration significantly attenuated pulmonary ferroptosis while concurrently mitigating inflammation and oxidative damage, ultimately ameliorating histological lung injury. Complementary in vitro studies demonstrated DMF's capacity to suppress lipopolysaccharide (LPS)-induced ferroptosis in MLE-12 cells. Mechanistic analyses identified dual protective pathways. DMF not only inhibited LPS-triggered STING activation and subsequent proinflammatory cytokine production but also prevented STING-mediated autophagic degradation of glutathione peroxidase 4 (GPX4). This dual action effectively reduced reactive oxygen species (ROS) accumulation and ferroptotic cell death. These findings position DMF as a promising therapeutic candidate with dual pharmacological actions - functioning as both a STING pathway inhibitor and ferroptosis suppressor.