Nuclear factor erythroid 2-related factor 2 (Nrf2) is an intracellular transcription factor that helps protect against oxidative stress in different types of cells under pathological conditions. Mitochondria are vital organelles that function in diverse metabolic processes in the body, including redox reactions, lipid metabolism, and cell death. Mitophagy, a specific form of autophagy for damaged mitochondria, plays a critical role in the pathophysiology of liver diseases. In this review, we explain in detail the roles of the Nrf2 signaling pathway and mitophagy, and the relationship between them, in various hepatic diseases (nonalcoholic fatty liver disease, viral hepatitis, alcoholic liver disease, drug-induced liver injury, autoimmune hepatitis, hepatic ischemia‒reperfusion injury, and liver cancer). We also offer some potential insights and treatments relevant to clinical applications.
Humans ; NF-E2-Related Factor 2/metabolism* ; Mitophagy/physiology* ; Kelch-Like ECH-Associated Protein 1/metabolism* ; Signal Transduction ; Liver Diseases/etiology* ; Animals ; Oxidative Stress ; Mitochondria/metabolism* ; Non-alcoholic Fatty Liver Disease ; Liver Neoplasms

OBJECTIVES: To investigate the protective effect of Yiqi Yangyin Huazhuo Tongluo Formula (YYHT) against high glucose-induced injury in mouse renal podocytes (MPC5 cells) and the possible mechanism. METHODS: Adult Wistar rats were treated with 19, 38, and 76 g/kg YYHT or saline via gavage for 7 days to prepare YYHT-medicated or blank sera for treatment of MPC5 cells cultured in high glucose (30 mmol/L) prior to transfection with a miR-21a-5p inhibitor or a miR-21a-5p mimic. The changes in miR-21a-5p expressions and the mRNA levels of FoxO1, PINK1, and Parkin in the treated cells were detected with qRT-PCR, and the protein levels of nephrin, podocin, FoxO1, PINK1, and Parkin were detected with Western blotting. Autophagic activity in the cells were evaluated with MDC staining. The effect of miR-21a-5p mimic on FoxO1 transcription and the binding of miR-21a-5p to FoxO1 were examined with luciferase reporter gene assay and radioimmunoprecipitation assay. RESULTS: MPC5 cells exposed to high glucose showed significantly increased miR-21a-5p expression, lowered expressions of FoxO1, PINK1, and Parkin1 mRNAs, and reduced levels of FoxO1, PINK1, parkin, nephrin, and podocin proteins and autophagic activity. Treatment of the exposed cells with YYHT-medicated sera and miR-21a-5p inhibitor both significantly enhanced the protein expressions of nephrin and podocin, inhibited the expression of miR-21a-5p, increased the mRNA and protein expressions of FoxO1, PINK1 and Parkin, and upregulated autophagic activity of the cells. Transfection with miR-21a-5p mimic effectively inhibited the transcription of FoxO1 and promoted the binding of miR-21a-5p to FoxO1 in MPC5 cells, and these effects were obviously attenuated by treatment with YYHT-medicated sera. CONCLUSIONS YYHT-medicated sera alleviate high glucose-induced injury in MPC5 cells by regulating miR-21a-5p/FoxO1/PINK1-mediated mitochondrial autophagy.
Animals ; MicroRNAs/genetics* ; Podocytes/pathology* ; Drugs, Chinese Herbal/pharmacology* ; Autophagy/drug effects* ; Rats, Wistar ; Protein Kinases/metabolism* ; Rats ; Forkhead Box Protein O1 ; Mice ; Mitochondria/drug effects* ; Ubiquitin-Protein Ligases/metabolism* ; Glucose ; Diabetic Nephropathies ; Male ; Membrane Proteins/metabolism* ; Intracellular Signaling Peptides and Proteins

OBJECTIVES: To investigate the role of the BNIP3-PI3K/Akt signaling pathway in mediating the inhibitory effect of Buyang Huanwu Decoction (BYHWT) on mitochondrial autophagy in human synovial fibroblasts from rheumatoid arthritis patients (FLS-RA) cultured under a hypoxic condition. METHODS: Forty normal Wistar rats were randomized into two groups (n=20) for daily gavage of BYHWT or distilled water for 7 days to prepare BYHWT-medicated or control sera. FLS-RA were cultured in routine condition or exposed to hypoxia (10% O₂) for 24 h wigh subsequent treatment with IL-1β, followed by treatment with diluted BYHWT-medicated serum (5%, 10% and 20%) or control serum. AnnexinV-APC/7-AAD double staining and T-AOC kit were used for detecting apoptosis and total antioxidant capacity of the cells, and the changes in ROS, ATP level, mitochondrial membrane potential and Ca²⁺ homeostasis were analyzed. The changes in mRNA and protein expressions of BNIP3, PI3K and AKT and mRNA expressions of LC3, Beclin-1 and P62 were detected using RT-qPCR and Western blotting. RESULTS: Treatment with BYHWT-medicated serum dose-dependently lowered apoptosis rate of IL-1β-induced FLS-RA with hypoxic exposure. The treatment significantly decreased T-AOC concentration, increased ROS production, autophagosome formation and ATPase levels, and lowered mitochondrial membrane potential and Ca²⁺ level in the cells. In IL-1β-induced FLS-RA with hypoxic exposure, treatment with BYHWT-medicated serum significantly increased BNIP3 protein expression, decreased the protein expressions of PI3K and AKT, increased the mRNA expressions of BNIP3 and P62, and lowered the mRNA expressions of PI3K, AKT, LC3 and Beclin-1 without significantly affecting Beclin-1 protein expression. The cells treated with 5% and 10% BYHWT-medicated serum showed no significant changes in LC3 expression. CONCLUSIONS BYHWT inhibits mitochondrial autophagy in IL-1β-induced FLS-RA with hypoxic exposure possibly by inhibiting BNIP3-mediated PI3K/AKT signaling pathway.
Drugs, Chinese Herbal/pharmacology* ; Arthritis, Rheumatoid/pathology* ; Animals ; Signal Transduction/drug effects* ; Proto-Oncogene Proteins c-akt/metabolism* ; Autophagy/drug effects* ; Humans ; Fibroblasts/cytology* ; Rats, Wistar ; Membrane Proteins/metabolism* ; Rats ; Phosphatidylinositol 3-Kinases/metabolism* ; Mitochondria/metabolism* ; Cells, Cultured ; Proto-Oncogene Proteins/metabolism* ; Apoptosis/drug effects* ; Cell Hypoxia ; Synovial Membrane/cytology* ; Male ; Mitochondrial Proteins

OBJECTIVES: To explore the correlation of hypertension with postoperative cognitive dysfunction and its possible mechanism. METHODS: Twelve-week-old spontaneously hypertensive rats (SHRs) and Wistar-Kyoto (WKY) rats were both randomized into control group and surgical group (n=8). In the latter group, the rats received carotid artery exposure surgery under sevoflurane anesthesia to establish models of postoperative learning and memory impairment. Postoperative cognitive function changes of the rats were evaluated using behavioral tests. The hippocampus of the rats were collected for determining ATP level and mitochondrial membrane potential (MMP) and for detecting expressions of UCP2 and astrocyte markers (GFAP and NOX4) using Western blotting and immunofluorescence staining. Serum levels of ROS, IL-6, IL-1β and TNF‑α were detected using ELISA. Nissl staining was used to examine hippocampal neuronal loss in the CA1 region. RESULTS: The SHRs exhibited exacerbated learning and memory deficits following the surgery as shown by significantly reduced performance in novel object recognition tests and context-related and tone-related fear conditioning experiments. Compared with WKY rats, the SHRs had significantly decreased mitochondrial UCP2 expression and MMP in the hippocampus, increased hippocampal ATP level, and markedly increased serum levels of ROS and inflammatory factors, showing also increased activation of hippocampal astrocytes and microglia and reduced number of neurons positive for Nissl staining. CONCLUSIONS Hypertension can exacerbate major postoperative learning and memory impairment in rats possibly as a result of UCP2-mediated mitochondrial dysfunction and oxidative stress damage, which further leads to astrocyte overactivation and neuronal damage.
Animals ; Rats, Inbred SHR ; Rats ; Uncoupling Protein 2 ; Rats, Inbred WKY ; Hypertension/physiopathology* ; Hippocampus/metabolism* ; Mitochondria/metabolism* ; Down-Regulation ; Male ; Memory Disorders/etiology* ; Mitochondrial Proteins/metabolism*

OBJECTIVES: To explore the mechanism of Shenqi Buzhong (SQBZ) Formula for alleviating mitochondrial dysfunction in a rat model of chronic obstructive pulmonary disease (COPD) in light of the AMPK/SIRT1/PGC-1α pathway. METHODS: Fifty male SD rat models of COPD, established by intratracheal lipopolysaccharide (LPS) instillation, exposure to cigarette smoke, and gavage of Senna leaf infusion, were randomized into 5 groups (n=10) for treatment with saline (model group), SQBZ Formula at low, moderate and high doses (3.08, 6.16 and 12.32 g/kg, respectively), or aminophylline (0.024 g/kg) by gavage for 4 weeks, with another 10 untreated rats as the control group. Pulmonary function of the rats were tested, and pathologies and ultrastructural changes of the lung tissues were examined using HE staining and transmission electron microscopy. The levels of SOD, ATP, MDA, and mitochondrial membrane potential in the lungs were detected using WST-1, colorimetric assay, TBA, and JC-1 methods. Flow cytometry was used to analyze ROS level in the lung tissues, and the protein expression levels of P-AMPKα, AMPKα, SIRTI, and PGC-1α were detected using Western blotting. RESULTS: The rat models of COPD showed significantly decreased lung function, severe histopathological injuries of the lungs, decreased pulmonary levels of SOD activity, ATP and mitochondrial membrane potential, increased levels of MDA and ROS, and decreased pulmonary expressions of P-AMPKα, SIRTI, and PGC-1α proteins. All these changes were significantly alleviated by treatment with SQBZ Formula and aminophylline, and the efficacy was comparable between high-dose SQBZ Formula group and aminophylline group. CONCLUSIONS SQBZ Formula ameliorates mitochondrial dysfunction in COPD rats possibly by activating the AMPK/SIRT1/PGC-1α pathway.
Animals ; Pulmonary Disease, Chronic Obstructive/drug therapy* ; Drugs, Chinese Herbal/therapeutic use* ; Sirtuin 1/metabolism* ; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha ; Rats, Sprague-Dawley ; Male ; Rats ; AMP-Activated Protein Kinases/metabolism* ; Mitochondria/metabolism* ; Disease Models, Animal ; Signal Transduction/drug effects*

OBJECTIVES: To investigate the molecular mechanism by which salvianolic acid B (Sal-B) modulates mitochondrial functional homeostasis and alleviates myocardial ischemia-reperfusion (I/R) injury in mice. METHODS: Mouse cardiomyocyte HL-1 cells were pretreated with 5 μmol/L Sal-B with or without sh-Sirt1 transfection before exposure to hypoxia-reoxygenation (HR), and the changes in ATP production, mitochondrial superoxide activity, substrate oxidation level were evaluated. In the animal experiment, 36 C57BL/6J mice were randomized into 3 groups (n=12) for sham operation or ligation of the left anterior coronary artery to induce myocardial I/R injury with or without intravenous injection of Sal-B+I/R (50 mg/kg). In the rescue experiment, 60 adult C57BL/6J mice were randomized into 5 groups (n=12): sham-operated group, myocardial I/R group, Sal-B+I/R group, I/R+Sal-B+Sirt1fl/fl group, and I/R+Sal-B+cKO-Sirt1 group. Myocardial injury was evaluated with HE staining, and cardiac function was assessed by measurement of the ejection fraction and fractional shortening using echocardiography. RESULTS: In HL-1 cells with HR injury, Sal-B pretreatment significantly increased cellular ATP production, reduced mitochondrial superoxide anion levels, and enhanced oxygen consumption level. In the mouse models of myocardial I/R injury, Sal-B pretreatment markedly ameliorated I/R-induced structural disarray of the cardiac myocytes and improved cardiac ejection. Cycloheximide chase with Western blotting and ubiquitination assays after Sirt1-IP showed that Sal-B significantly inhibited Sirt1 degradation in HL-1 cells. Sirt1 knock-down reversed Sal-B-induced increases in ATP production, reduction in superoxide, and elevation of OCR in HL-1 cells. Cardiomyocyte-specific Sirt1 knockout obviously reversed Sal-B-mediated improvement in cardiac ejection function and myocardial structure damage in mice with myocardial I/R injury. CONCLUSIONS Sal-B promotes mitochondrial functional homeostasis in cardiomyocytes with HR injury and improves cardiac function in mice after myocardial I/R by inhibiting Sirt1 protein degradation.
Animals ; Sirtuin 1/metabolism* ; Myocardial Reperfusion Injury/physiopathology* ; Mice, Inbred C57BL ; Mice ; Myocytes, Cardiac/drug effects* ; Benzofurans/pharmacology* ; Homeostasis/drug effects* ; Male ; Mitochondria/drug effects* ; Depsides

OBJECTIVES: To investigate the molecular mechanism by which Lichong Xiaozheng Granules (LCXZ) sensitize ovarian cancer to cisplatin (DDP) treatment. METHODS: LC-MS analysis was used to identify the blood components of LCXZ after its administration in mice via gavage. In a BALB/c mouse model bearing subcutaneous ovarian cancer xenografts, the effects of daily gavage of distilled water (control group), intraperitoneal injection of DDP (5 mg/kg) once a week, or both DDP injection and daily LCXZK gavage (15 g/kg) on tumor growth were evaluated. Histopathological changes in the xenografts and kidneys were assessed with HE staining. RNA-seq was performed to identify the differentially expressed genes followed by KEGG pathway analysis. The changes in mitochondrial ultrastructure and expressions of mitochondrial apoptosis-related were examined with transmission electron microscopy and Western blotting. RESULTS: A total of 218 blood-borne components of LCXZ were detected by LC-MS. In the tumor-bearing mice, treatments with DDP and DDP combined with LCXZ redcued the tumor volume by 60.3% and 72.6% compared with that in the control group, respectively. Transcriptomic analysis revealed significantly upregulated ANT3 expression in both the two treatment groups. Molecular docking indicated that the main active components of LCXZ were capable of binding to adenine nucleotide translocator 3 (ANT3) with binding energies below -6 kcal/mol. Transmission electron microscopy showed obvious mitochondrial swelling and outer-membrane damage in the tumor cells in DDP-treated mice, and these changes were more pronounced in the combined treatment group. The expression levels of BAX, ANT3, cleaved caspase-3 and cleaved caspase-9 were increased, whereas BCL-2 expression was decreased significantly in the tumor cells in both the DDP and DDP+LCXZ groups. CONCLUSIONS LCXZ enhances the therapeutic efficacy of cisplatin against ovarian cancer xenografts in mice by promoting mitochondrial dysfunction and activating apoptotic signaling pathways via upregulating ANT3.
Animals ; Female ; Cisplatin/pharmacology* ; Ovarian Neoplasms/metabolism* ; Apoptosis/drug effects* ; Mitochondria/metabolism* ; Drugs, Chinese Herbal/pharmacology* ; Mice, Inbred BALB C ; Mice ; Rats ; Xenograft Model Antitumor Assays ; Humans ; Cell Line, Tumor ; Antineoplastic Agents/pharmacology*

OBJECTIVES: To investigate the mechanism underlying the therapeutic effect of electroacupuncture (EA) on post-traumatic stress disorder (PTSD) in rats. METHODS: Forty male SD rats were randomized equally into blank control group, PTSD model group, sham-acupuncture group, paroxetine group, and EA group. In the latter 3 groups, the rat models of PTSD, induced by continuous single-prolonged stress and plantar electrical stimulation, were treated with EA at GV20, GV24, BL18 and BL23 acupoints for 15 min (5 times a week for 3 weeks), sham-acupuncture without electrical stimulation, or gavage with paroxetine suspension on the same schedule. Behavioral changes of the rats were evaluated using open field test (OFT) and elevated plus maze (EPM) test. Hippocampal pathologies and neuronal changes were examined with HE and Nissl staining, and mitochondrial ultrastructure was examined using electron microscopy. The mRNA and protein expression levels of Bcl-2, Bax, and caspase-3 were detected by RT-qPCR and immunofluorescence staining. RESULTS: The rat models of PTSD showed significantly reduced total distance traveled in OFT and distance and time spent in the open arms of the EPM, with decreased hippocampal neurons, obvious neuronal and mitochondrial pathologies, decreased hippocampal expression of Bcl-2, and increased Bax and caspase-3 expressions. Treatments with paroxetine and EA both significantly improved behavioral changes of the rat models, increased the number of Nissl-stained neurons, obviously alleviated pathologies in the hippocampal neurons and mitochondrial ultrastructure, increased hippocampal Bcl-2 expression, and lowered caspase-3 expressions. Paroxetine showed significantly better effect than EA for improving performance of the rats in EPM test, whereas sham-acupuncture did not produce any significant improvement. CONCLUSIONS EA alleviates PTSD in rats possibly by upregulating Bcl-2 and downregulating Bax and caspase-3, thereby ameliorating hippocampal mitochondrial damage.
Animals ; Electroacupuncture ; Stress Disorders, Post-Traumatic/metabolism* ; Hippocampus/pathology* ; Rats, Sprague-Dawley ; Male ; Rats ; Mitochondria/pathology* ; Signal Transduction ; bcl-2-Associated X Protein/metabolism* ; Caspase 3/metabolism* ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; Disease Models, Animal

OBJECTIVES: To explore the mechanism by which astragaloside IV (AS-IV) alleviates D-galactose (D-GAL)-induced senescence in human umbilical vein endothelial cells (HUVECs). METHODS: Cultured HUVECs were treated with D-GAL (40 g/L), AS-IV (200 μmol/L), D-GAL+AS-IV, or D-GAL+AS-IV+MTK458 (a mitochondrial autophagy agonist, 25 μmol/L) for 48 h, and the changes in cell proliferation, migration, and angiogenesis capacity were evaluated. Cell apoptosis, reactive oxygen species (ROS) levels, mitochondrial membrane potential, and expressions of autophagy-related proteins (LC3-II/LC3-I) and PINK1/Parkin pathway proteins in the treated cells were detected. RESULTS: AS-IV treatment significantly reduced the inhibitory effect of D-GAL on HUVEC viability, effectively alleviated D-GAL-induced impairment of tube-forming ability, and promoted angiogenesis and migration ability of the cells. AS-IV also significantly reduced the rate of D-GAL-induced HUVECs positive for senescence-associated β-galactosidase (SA-β-Gal) staining and inhibited the expression of senescence-related genes P21 and P53. AS-IV restored mitochondrial membrane potential and reduced intracellular ROS levels in D-GAL-induced HUVECs, and inhibited the fusion of autophagosomes and lysosomes to prevent the completion of autophagic flux. In HUVECs treated with both D-GAL and AS-IV, the application MTK458 significantly increased the number of yellow spots and enhanced the expressions of P21, P53, PINK1, Parkin, LC3, and Beclin proteins. CONCLUSIONS AS-IV alleviates D-GAL-induced endothelial cell senescence by inhibiting the PINK1/Parkin pathway to regulate mitochondrial autophagy.
Humans ; Human Umbilical Vein Endothelial Cells/drug effects* ; Cellular Senescence/drug effects* ; Autophagy/drug effects* ; Saponins/pharmacology* ; Ubiquitin-Protein Ligases/metabolism* ; Mitochondria/drug effects* ; Triterpenes/pharmacology* ; Protein Kinases/metabolism* ; Galactose/pharmacology* ; Reactive Oxygen Species/metabolism* ; Signal Transduction/drug effects* ; Cells, Cultured ; Apoptosis/drug effects* ; Membrane Potential, Mitochondrial ; Cell Proliferation/drug effects*

Acute mitochondrial damage and the energy crisis following axonal injury highlight mitochondrial transport as an important target for axonal regeneration. Syntaphilin (Snph), known for its potent mitochondrial anchoring action, has emerged as a significant inhibitor of both mitochondrial transport and axonal regeneration. Therefore, investigating the molecular mechanisms that influence the expression levels of the snph gene can provide a viable strategy to regulate mitochondrial trafficking and enhance axonal regeneration. Here, we reveal the inhibitory effect of microRNA-146b (miR-146b) on the expression of the homologous zebrafish gene syntaphilin b (snphb). Through CRISPR/Cas9 and single-cell electroporation, we elucidated the positive regulatory effect of the miR-146b-snphb axis on Mauthner cell (M-cell) axon regeneration at the global and single-cell levels. Through escape response tests, we show that miR-146b-snphb signaling positively regulates functional recovery after M-cell axon injury. In addition, continuous dynamic imaging in vivo showed that reprogramming miR-146b significantly promotes axonal mitochondrial trafficking in the pre-injury and early stages of regeneration. Our study reveals an intrinsic axonal regeneration regulatory axis that promotes axonal regeneration by reprogramming mitochondrial transport and anchoring. This regulation involves noncoding RNA, and mitochondria-associated genes may provide a potential opportunity for the repair of central nervous system injury.
Animals ; Zebrafish ; MicroRNAs/genetics* ; Nerve Regeneration/physiology* ; Mitochondria/metabolism* ; Zebrafish Proteins/genetics* ; Axons/metabolism* ; Signal Transduction/physiology* ; Axonal Transport/physiology* ; Nerve Tissue Proteins/genetics*