OBJECTIVES: To investigate the antioxidative mechanism of snake venom-derived protein C activator (PCA) in mitigating vascular endothelial cell injury. METHODS: Human umbilical vein endothelial cells (HUVECs) were cultured in DMEM containing 1.0 g/L D-glucose and exposed to hypoxia (1% O₂) for 6 h followed by reoxygenation for 2 h to establish a cell model of oxygen-glucose deprivation/reoxygenation (OGD/R). The cell model was treated with 2 μg/mL PCA alone or in combination with 2-ME2 (a HIF-1α inhibitor) or DMOG (a HIF-1α stabilizer), and intracellular production of reactive oxygen species (ROS) and protein expression levels of HIF-1α, BNIP3, and Beclin-1 were detected using DCFH-DA fluorescence probe, flow cytometry, and Western blotting. The OGD/R cell model was transfected with a BNIP3-specific siRNA or a scrambled control sequence prior to PCA treatment, and the changes in protein expressions of HIF-1α, BNIP3 and Beclin-1 and intracellular ROS production were examined. RESULTS: In the OGD/R cell model, PCA treatment significantly upregulated HIF-1α, BNIP3 and Beclin-1 expressions and reduced ROS production. The effects of PCA were obviously attenuated by co-treatment with 2-ME2 but augmented by treatment with DMOG (a HIF-1α stabilizer). In the cell model with BNIP3 knockdown, PCA treatment increased BNIP3 expression and decreased ROS production without causing significant changes in HIF-1α expression. Compared with HUVECs with PCA treatment only, the cells with BNIP3 knockdown prior to PCA treatment showed significantly lower Beclin-1 expression and higher ROS levels. CONCLUSIONS Snake venom PCA alleviates OGD/R-induced endothelial cell injury by upregulating HIF-1α/BNIP3 signaling to suppress ROS generation, suggesting its potential as a therapeutic agent against oxidative stress in vascular pathologies.
Humans ; Reactive Oxygen Species/metabolism* ; Hypoxia-Inducible Factor 1, alpha Subunit/metabolism* ; Human Umbilical Vein Endothelial Cells/drug effects* ; Membrane Proteins/metabolism* ; Proto-Oncogene Proteins/metabolism* ; Up-Regulation ; Cell Hypoxia ; Cells, Cultured ; Snake Venoms/chemistry* ; Beclin-1

OBJECTIVES: To explore the mechanism of Pingchuanning Formula (PCN) for inhibiting airway inflammation in rats with asthmatic cold syndrome. METHODS: A total of 105 SD rats were randomized equally into 7 groups, including a control group, an asthmatic cold syndrome model group, 3 PCN treatment groups at high, medium and low doses, a Guilong Kechuanning (GLCKN) treatment group, and a dexamethasone (DEX) treatment group. In all but the control rats, asthma cold syndrome models were established and daily gavage of saline, PCN, GLCKN or DEX was administered 29 days after the start of modeling. The changes in general condition, lung function and lung histopathology of the rats were observed, and inflammatory factors in the alveolar lavage fluid (BALF), oxidative stress, lung tissue ultrastructure, cytokine levels, and expressions of the genes related to the HMGB1/Beclin-1 axis and autophagy were analyzed. RESULTS: The rat models had obvious manifestations of asthmatic cold syndrome with significantly decreased body mass, food intake, and water intake, reduced FEV_0.3, FVC, and FEV_0.3/FVC, obvious inflammatory cell infiltration in the lung tissue, and increased alveolar inflammation score and counts of neutrophils, eosinophils, lymphocytes, macrophages, and leukocytes in the BALF. The rat models also had significantly increased MDA level and decreased SOD level and exhibited obvious ultrastructural changes in the lung tissues, where the expressions of HMGB1, Beclin-1, ATG5, TNF-α, IL-6,IL-1β, and IL-13 and the LC3II/I ratio were increased, while the levels of Bcl-2 and IFN-γ were decreased. PCN treatment significantly improved these pathological changes in the rat models, and its therapeutic effect was better than that of GLKCN and similar to that of DEX. CONCLUSIONS PCN can effectively alleviate airway inflammation in rat models of asthmatic cold syndrome possibly by modulating the HMGB1/Beclin-1 signaling axis to suppress cell autophagy, thereby attenuating airway inflammatory damages.
Animals ; Rats ; Autophagy/drug effects* ; Rats, Sprague-Dawley ; Asthma/pathology* ; Beclin-1 ; HMGB1 Protein/metabolism* ; Drugs, Chinese Herbal/therapeutic use* ; Disease Models, Animal ; Male ; Lung/pathology* ; Inflammation

OBJECTIVE: To investigate the mechanism of autophagy in regulating bacterial translocation in intestinal infection caused by hypervirulent Klebsiella pneumonia (hvKp) and explore the method of reducing translocation infection of intestinal bacteria. METHODS: Fifty C57BL/6J mice were divided into gavage group (n = 40) and control group (CO group, n = 10). The gavage group was orally administered with 200 μL/d of hvKp (colony count of 10⁹ CFU/mL) continuously for 5 days to establish a hvKp intestinal infection model. CO group was given an equal amount of normal saline. After the experiment, the mice were anesthetized with lsofluraneand euthanized with cervical dislocation under anesthesia. Peripheral venous blood of mice was collected to detect bacterial translocation by 16S rDNA sequencing, then divided into translocation group (BT+ group) and non-translocation group (BT- group). Hematoxylin-eosin (HE) staining was used to evaluate intestinal morphology. The ultrastructural changes of intestinal tissues were observed by electron microscope. The levels of intestinal oxidative stress indicators such as superoxide dismutase (SOD), malondialdehyde (MDA) and glutathione peroxidase (GPx) were measured. Translocation was detected by in situ hybridization. The expression of tight junction protein microtubule-associated protein 1 light chain 3-II (LC3-II) and autophagy protein Beclin-1 were measured by Western blotting. The mRNA expression of tight junction proteins ZO-1 and Claudin-2 were detected by reverse transcription-polymerase chain reaction (RT-PCR). The expression of autophagy protein and tight junction protein were observed by immunofluorescence. RESULTS: Two out of 40 mice in the gavage group died after developing aspiration pneumonia. All mice in the CO group survived. The 16S rDNA sequencing results showed that no bacteria were detected in the peripheral blood of the CO group, but bacteria were detected in the peripheral blood of 18 mice in the gavage group, with a bacterial translocation rate of 47.4%. The BT- and BT+ groups showed intestinal mucosal tissue damage, with severe damage in the BT+ group. Compared with the CO group, the level of MDA in the BT- and BT+ groups were significantly increased, while the activities of SOD and GPx were significantly decreased. Compared with the BT- group, the MDA level in the BT+ group further increased, while the SOD and GPx activities further decreased [MDA (mmol/mg): 2.98±0.11 vs. 2.48±0.11, SOD (U/mg): 62.40±5.45 vs. 73.40±4.08, GPx (U/mg): 254.72±10.80 vs. 303.55±8.57, all P < 0.01]. The results of in situ hybridization detection showed that after continuous gastric lavage for 5 days, displaced hvKp was detected in the intestinal mucosal lamina propria and liver tissue of the BT+ group. Compared with the CO group, the protein expressions of LC3-II and Beclin-1 in the BT- and BT+ groups were significantly increased. The protein expressions of LC3-II and Beclin-1 in the BT+ group were obviously lower than those in the BT- group (LC3-II/β-actin: 0.38±0.04 vs. 0.70±0.09, Beclin-1/β-actin: 0.62±0.05 vs. 0.86±0.05, both P < 0.01), and there were autophagosomes in the intestinal mucosa. These results indicated that intestinal mucosal autophagy was activated after hvKp continuous gavage. Compared with CO group, the mRNA expressions of ZO-1 and Claudin-2 in the BT- and BT+ groups were significantly decreased. Compared with the BT- group, the mRNA expressions of ZO-1 and Claudin-2 in the BT+ group was further reduced [ZO-1 mRNA (2^-ΔΔCT): 0.78±0.06 vs. 0.88±0.06, Claudin-2 mRNA (2^-ΔΔCT): 0.40±0.04 vs. 0.70±0.06, both P < 0.01]. The immunofluorescence results showed that the fluorescence intensity of LC3-II, Beclin-1, ZO-1, and Claudin-2 in the BT+ group was significantly lower than that in the BT- group. CONCLUSION HvKp can activate intestinal mucosal autophagy and reduce the damage to intestinal mucosal barrier function by down-regulating oxidative stress level, reduce the occurrence of bacterial translocation.
Animals ; Oxidative Stress ; Mice, Inbred C57BL ; Autophagy ; Intestinal Mucosa/microbiology* ; Bacterial Translocation ; Mice ; Klebsiella Infections/microbiology* ; Superoxide Dismutase/metabolism* ; Beclin-1

BACKGROUND: Salvianolate is a compound mainly composed of salvia magnesium acetate, which is extracted from the Chinese herb Salvia miltiorrhiza . In recent years, salvianolate injection has been widely used in the treatment of cardiovascular diseases, but the mechanism of how it can alleviate cardiotoxicity remains unclear. METHODS: The cardiac injury model was constructed by treatment with doxorubicin (Dox) or azithromycin (Azi) in zebrafish larvae. Heart phenotype, heart rate, and cardiomyocyte apoptosis were observed in the study. RNA-sequencing (RNA-seq) analysis was used to explore the underlying mechanism of salvianolate treatment. Moreover, cardiomyocyte autophagy was assessed by in situ imaging. In addition, the miR-30a/becn1 axis regulation by salvianolate was further investigated. RESULTS: Salvianolate treatment reduced the proportion of pericardial edema, recovered heart rate, and inhibited cardiomyocyte apoptosis in Dox/Azi-administered zebrafish larvae. Mechanistically, salvianolate regulated the lysosomal pathway and promoted autophagic flux in zebrafish cardiomyocytes. The expression level of becn1 was increased in Dox-induced myocardial tissue injury after salvianolate administration; overexpression of becn1 in cardiomyocytes alleviated the Dox/Azi-induced cardiac injury and promoted autophagic flux in cardiomyocytes, while becn1 knockdown blocked the effects of salvianolate. In addition, miR-30a, negatively regulated by salvianolate, partially inhibited the cardiac amelioration of salvianolate by targeting becn1  directly. CONCLUSION This study has proved that salvianolate reduces cardiomyopathy by regulating autophagic flux through the miR-30a/becn1 axis in zebrafish and is a potential drug for adjunctive Dox/Azi therapy.
Animals ; Zebrafish ; MicroRNAs/genetics* ; Autophagy/drug effects* ; Myocytes, Cardiac/metabolism* ; Cardiomyopathies/metabolism* ; Beclin-1/genetics* ; Apoptosis/drug effects* ; Plant Extracts/therapeutic use* ; Doxorubicin

OBJECTIVE: To explore the mechanism of electroacupuncture (EA) in promoting recovery of the facial function with the involvement of autophagy, glial cell line-derived neurotrophic factor (GDNF), and phosphatidylinositol-3-kinase (PI3K)/mammalian target of rapamycin (mTOR) signaling pathway. METHODS: Seventy-two male Sprague-Dawley rats were randomly allocated into the control, sham-operated, facial nerve injury (FNI), EA, EA+3-methyladenine (3-MA), and EA+GDNF antagonist groups using a random number table, with 12 rats in each group. An FNI rat model was established with facial nerve crushing method. EA intervention was conducted at Dicang (ST 4), Jiache (ST 6), Yifeng (SJ 17), and Hegu (LI 4) acupoints for 2 weeks. The Simone's 10-Point Scale was utilized to monitor the recovery of facial function. The histopathological evaluation of facial nerves was performed using hematoxylin-eosin (HE) staining. The levels of Beclin-1, light chain 3 (LC3), and P62 were detected by immunohistochemistry (IHC), immunofluorescence, and reverse transcription-polymerase chain reaction, respectively. Additionally, IHC was also used to detect the levels of GDNF, Rai, PI3K, and mTOR. RESULTS: The facial functional scores were significantly increased in the EA group than the FNI group (P<0.05 or P<0.01). HE staining showed nerve axons and myelin sheaths, which were destroyed immediately after the injury, were recovered with EA treatment. The expressions of Beclin-1 and LC3 were significantly elevated and the expression of P62 was markedly reduced in FNI rats (P<0.01); however, EA treatment reversed these abnormal changes (P<0.01). Meanwhile, EA stimulation significantly increased the levels of GDNF, Rai, PI3K, and mTOR (P<0.01). After exogenous administration with autophagy inhibitor 3-MA or GDNF antagonist, the repair effect of EA on facial function was attenuated (P<0.05 or P<0.01). CONCLUSIONS EA could promote the recovery of facial function and repair the facial nerve damages in a rat model of FNI. EA may exert this neuroreparative effect through mediating the release of GDNF, activating the PI3K/mTOR signaling pathway, and further regulating the autophagy of facial nerves.
Rats ; Male ; Animals ; Rats, Sprague-Dawley ; Electroacupuncture ; Phosphatidylinositol 3-Kinase/metabolism* ; Facial Nerve Injuries/therapy* ; Phosphatidylinositol 3-Kinases/metabolism* ; Beclin-1 ; Glial Cell Line-Derived Neurotrophic Factor ; Signal Transduction ; TOR Serine-Threonine Kinases/metabolism* ; Autophagy ; Mammals/metabolism*

OBJECTIVES: To study the effect of ligustrazine injection on mitophagy in neonatal rats with hypoxic-ischemic encephalopathy (HIE) and its molecular mechanism. METHODS: Neonatal Sprague-Dawley rats, aged 7 days, were randomly divided into a sham-operation group with 8 rats, a model group with 12 rats, and a ligustrazine group with 12 rats. The rats in the model group and the ligustrazine group were used to establish a neonatal rat model of HIE by ligation of the left common carotid artery followed by hypoxia treatment, and blood vessels were exposed without any other treatment for the rats in the sham-operation group. The rats in the ligustrazine group were intraperitoneally injected with ligustrazine (20 mg/kg) daily after hypoxia-ischemia, and those in the sham-operation group and the model group were intraperitoneally injected with an equal volume of normal saline daily. Samples were collected after 7 days of treatment. Hematoxylin and eosin staining and Nissl staining were used to observe the pathological changes of neurons in brain tissue; immunohistochemical staining was used to observe the positive expression of PINK1 and Parkin in the hippocampus and cortex; TUNEL staining was used to measure neuronal apoptosis; Western blotting was used to measure the expression levels of the mitophagy pathway proteins PINK1 and Parkin and the autophagy-related proteins Beclin-1, microtubule-associated protein 1 light chain 3 (LC3), and ubiquitin-binding protein (P62). RESULTS: Compared with the sham-operation group, the model group had a significant reduction in the number of neurons, an increase in intercellular space, loose arrangement, lipid vacuolization, and a reduction in Nissl bodies. The increased positive expression of PINK1 and Parkin, apoptosis rate of neurons, and protein expression levels of PINK1, Parkin, Beclin1 and LC3 (P<0.05) and the decreased protein expression level of P62 in the hippocampus were also observed in the model group (P<0.05). Compared with the model group, the ligustrazine group had a significant increase in the number of neurons with ordered arrangement and an increase in Nissl bodies, significant reductions in the positive expression of PINK1 and Parkin, the apoptosis rate of neurons, and the protein expression levels of PINK1, Parkin, Beclin1, and LC3 (P<0.05), and a significant increase in the protein expression level of P62 (P<0.05). CONCLUSIONS Ligustrazine can alleviate hypoxic-ischemic brain damage and inhibit neuronal apoptosis in neonatal rats to a certain extent, possibly by inhibiting PINK1/Parkin-mediated autophagy.
Rats ; Animals ; Hypoxia-Ischemia, Brain/metabolism* ; Animals, Newborn ; Rats, Sprague-Dawley ; Beclin-1 ; Autophagy ; Ubiquitin-Protein Ligases/metabolism* ; Protein Kinases/metabolism*

OBJECTIVE: To investigate autophagy-related mechanisms of electroacupuncture (EA) action in improving gastrointestinal motility in mice with functional constipation (FC). METHODS: According to a random number table, the Kunming mice were divided into the normal control, FC and EA groups in Experiment I. The autophagy inhibitor 3-methyladenine (3-MA) was used to observe whether it antagonized the effects of EA in Experiment II. An FC model was established by diphenoxylate gavage. Then the mice were treated with EA stimulation at Tianshu (ST 25) and Shangjuxu (ST 37) acupoints. The first black stool defecation time, the number, weight, and water content of 8-h feces, and intestinal transit rate were used to assess intestinal transit. Colonic tissues underwent histopathological assessment, and the expressions of autophagy markers microtubule-associated protein 1 light chain 3 (LC3) and Beclin-1 were detected by immunohistochemical staining. The expressions of phosphoinositide 3-kinases (PI3K)-protein kinase B (AKT)-mammalian target of rapamycin (mTOR) signaling pathway members were investigated by Western blot and quantitative reverse transcription-polymerase chain reaction, respectively. The relationship between enteric glial cells (EGCs) and autophagy was observed by confocal immunofluorescence microscopy, localization analysis, and electron microscopy. RESULTS: EA treatment shortened the first black stool defecation time, increased the number, weight, and water content of 8-h feces, and improved the intestinal transit rate in FC mice (P<0.01). In terms of a putative autophagy mechanism, EA treatment promoted the expressions of LC3 and Beclin-1 proteins in the colonic tissue of FC mice (P<0.05), with glial fibrillary acidic protein (GFAP) and LC3 significantly colocalized. Furthermore, EA promoted colonic autophagy in FC mice by inhibiting PI3K/AKT/mTOR signaling (P<0.05 or P<0.01). The positive effect of EA on intestinal motility in FC mice was blocked by 3-MA. CONCLUSION EA treatment can inhibit PI3K/AKT/mTOR signaling in the colonic tissues of FC mice, thereby promoting EGCs autophagy to improve intestinal motility.
Mice ; Animals ; Proto-Oncogene Proteins c-akt/metabolism* ; Phosphatidylinositol 3-Kinases/metabolism* ; Electroacupuncture ; Beclin-1 ; Signal Transduction ; Constipation/therapy* ; TOR Serine-Threonine Kinases/metabolism* ; Autophagy ; Neuroglia/metabolism* ; Mammals/metabolism*

OBJECTIVE: To investigate the effects of gene of phosphate and tension homology (PTEN)-induced putative kinase 1 (PINK1)/Parkin pathway on hippocampal mitophagy and cognitive function in mice with sepsis-associated encephalopathy (SAE) and its possible mechanism. METHODS: A total of 80 male C57BL/6J mice were randomly divided into Sham group, cecal ligation puncture (CLP) group, PINK1 plasmid transfection pretreatment groups (p-PINK1+Sham group, p-PINK1+CLP group), empty vector plasmid transfection control group (p-vector+CLP group), with 16 mice in each group. The mice in CLP groups were treated with CLP to reproduce SAE models. The mice in the Sham groups were performed laparotomy only. Animals in the p-PINK1+Sham and p-PINK1+CLP groups were transfected with PINK1 plasmid through the lateral ventricle at 24 hours before surgery, while mice in the p-vector+CLP group were transfected with the empty plasmid. Morris water maze experiment was performed 7 days after CLP. The hippocampal tissues were collected, the pathological changes were observed under a light microscope after hematoxylin-eosin (HE) staining, and the mitochondrial autophagy was observed under a transmission electron microscopy after uranyl acetate and lead citrate staining. The expressions of PINK1, Parkin, Beclin1, interleukins (IL-6, IL-1β) and microtubule-associated protein 1 light chain 3 (LC3) were detected by Western blotting. RESULTS: Compared with the Sham group, CLP group mice in Morris water maze experiment had longer escape latency, shorter target quadrant residence time, and fewer times of crossing the platform at 1-4 days. Under the light microscope, the hippocampal structure of the mouse was injured, the neuronal cells were arranged in disorder, and the nuclei were pyknotic. Under the electron microscope, the mitochondria appeared swollen, round, and wrapped by bilayer or multilayer membrane structures. Compared with the Sham group, CLP group had higher expressions of PINK1, Parkin, Beclin1, LC3II/LC3I ratio, IL-6 and IL-1β in hippocampus, indicating that sepsis induced by CLP could activated inflammatory response and caused PINK1/Parkin-mediated mitophagy. Compared with the CLP group, p-PINK1+CLP group had shorter escape latencies, spent more time in the target quadrant and had more number of crossings in the target quadrant at 1-4 days. Under the light microscope, the hippocampal structures of mice was destroyed, the neurons were arranged disorderly, and the nuclei were pyknotic. Under transmission electron microscope, swollen and rounded mitochondria and mitochondrial structure wrapped by double membrane or multilayer membrane structure were observed. Compared with the CLP group, the levels of PINK1, Parkin, Beclin1 and LC3II/LC3 ratio in the p-PINK1+CLP group were significantly increased [PINK1 protein (PINK1/β-actin): 1.95±0.17 vs. 1.74±0.15, Parkin protein (Parkin/β-actin): 2.06±0.11 vs. 1.78±0.12, Beclin1 protein (Beclin1/β-actin): 2.11±0.12 vs. 1.67±0.10, LC3II/LC3I ratio: 3.63±0.12 vs. 2.27±0.10, all P < 0.05], while the levels of IL-6 and IL-1β were significantly decreased [IL-6 protein (IL-6/β-actin): 1.69±0.09 vs. 2.00±0.11, IL-1β protein (IL-1β/β-actin): 1.11±0.12 vs. 1.65±0.12, both P < 0.05], suggesting that overexpression of PINK1 protein could further activate mitophagy and reduce the inflammatory response caused by sepsis. There was no statistically significant difference in the above pathological changes and related indicators between Sham group and p-PINK1+Sham group, CLP group and p-vector+CLP group. CONCLUSIONS PINK1 overexpression can further activate CLP-induced mitophagy by upregulating Parkin, thereby inhibiting inflammation response and alleviate cognitive function impairment in SAE mice.
Male ; Animals ; Mice ; Mice, Inbred C57BL ; Sepsis-Associated Encephalopathy ; Phosphates ; Actins ; Beclin-1 ; Interleukin-6 ; Autophagy ; Ubiquitin-Protein Ligases ; Cognitive Dysfunction ; Sepsis ; Mitochondria ; Protein Kinases

OBJECTIVE: To investigate the effects of tanshinone IIA on apoptosis and autophagy induced by hypoxia/reoxygenation in H9C2 cardiomyocytes and its mechanism. METHODS: H9C2 cardiomyocytes in logarithmic growth phase were divided into control group, hypoxia/reoxygenation model group and tanshinone IIA low-dose, medium-dose and high-dose groups (50, 100, 200 mg/L tanshinone IIA were treated after hypoxia/reoxygenation respectively). The dose with good therapeutic effect was selected for follow-up study. The cells were divided into control group, hypoxia/reoxygenation model group, tanshinone IIA+pcDNA3.1-NC group and tanshinone IIA+pcDNA3.1-ABCE1 group. The cells were transfected with the overexpressed plasmids pcDNA3.1-ABCE1 and pcDNA3.1-NC and then treated accordingly. Cell counting kit-8 (CCK-8) was used to detect H9C2 cell activity in each group. The apoptosis rate of cardiomyocytes was detected by flow cytometry. The ATP-binding cassette transporter E1 (ABCE1), apoptosis-related proteins Bcl-2 and Bax, caspase-3, autophagy-related proteins Beclin-1, microtubule-associated protein 1 light chain 3 (LC3II/I) and p62 mRNA expression level of H9C2 cells in each group were detected by real-time fluorescence quantitative reverse transcription-polymerase chain reaction (RT-qPCR). The protein expression levels of the above indexes in H9C2 cells were detected by Western blotting. RESULTS: (1) Cell activity and ABCE1 expression: tanshinone IIA inhibited the activity of H9C2 cells induced by hypoxia/reoxygenation, and the effect was significant at medium-dose [(0.95±0.05)% vs. (0.37±0.10)%, P < 0.01], mRNA and protein expression of ABCE1 were significantly reduced [ABCE1 mRNA (2^-ΔΔCt): 2.02±0.13 vs. 3.74±0.17, ABCE1 protein (ABCE1/GAPDH): 0.46±0.04 vs. 0.68±0.07, both P < 0.05]. (2) Expression of apoptosis-related proteins: medium-dose of tanshinone IIA inhibited the apoptosis of H9C2 cells induced by hypoxia/reoxygenation [apoptosis rate: (28.26±2.52)% vs. (45.27±3.07)%, P < 0.05]. Compared with the hypoxia/reoxygenation model group, medium-dose of tanshinone IIA significantly down-regulated the protein expression of Bax and caspase-3 in H9C2 cells induced by hypoxia/reoxygenation, and significantly up-regulated the protein expression of Bcl-2 [Bax (Bax/GAPDH): 0.28±0.03 vs. 0.47±0.03, caspase-3 (caspase-3/GAPDH): 0.31±0.02 vs. 0.44±0.03, Bcl-2 (Bcl-2/GAPDH): 0.53±0.02 vs. 0.37±0.05, all P < 0.05]. (3) Expression of autophagy-related proteins: compared with the control group, the positive rate of LC3 in the hypoxia/reoxygenation model group was significantly increased, while the positive rate of LC3 in the medium-dose of tanshinone IIA group was significantly decreased [(20.67±3.09)% vs. (42.67±3.86)%, P < 0.01]. Compared with hypoxia/reoxygenation model group, medium-dose of tanshinone IIA significantly down-regulated Beclin-1, LC3II/I and p62 protein expressions [Beclin-1 (Beclin-1/GAPDH): 0.27±0.05 vs. 0.47±0.03, LC3II/I ratio: 0.24±0.05 vs. 0.47±0.04, p62 (p62/GAPDH): 0.21±0.03 vs. 0.48±0.02, all P < 0.05]. (4) Expression of apoptosis and autophagy related proteins after transfection with overexpressed ABCE1 plasmid: compared with tanshinone IIA+pcDNA3.1-NC group, the protein expression levels of Bax, caspase-3, Beclin-1, LC3II/I and p62 in tanshinone IIA+pcDNA3.1-ABCE1 group were significantly up-regulated, while the protein expression level of Bcl-2 was significantly down-regulated. CONCLUSIONS 100 mg/L tanshinone IIA could inhibit autophagy and apoptosis of cardiomyocytes by regulating the expression level of ABCE1. So, it protects H9C2 cardiomyocytes injury induced by hypoxia/reoxygenation.
Humans ; Apoptosis ; ATP-Binding Cassette Transporters/metabolism* ; Autophagy ; bcl-2-Associated X Protein/metabolism* ; Beclin-1/metabolism* ; Caspase 3/metabolism* ; Follow-Up Studies ; Myocytes, Cardiac ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; RNA, Messenger/metabolism* ; Cell Hypoxia

OBJECTIVE: To investigate whether hydrogen-rich water exerts a protective effect against cellular injury by affecting the level of autophagy after oxygen glucose deprivation/reoxygenation (OGD/R) in a mouse hippocampal neuronal cell line (HT22 cells). METHODS: HT22 cells in logarithmic growth phase were cultured in vitro. Cell viability was detected by cell counting kit-8 (CCK-8) assay to find the optimal concentration of Na₂S₂O₄. HT22 cells were divided into control group (NC group), OGD/R group (sugar-free medium+10 mmol/L Na₂S₂O₄ treated for 90 minutes and then changed to normal medium for 4 hours) and hydrogen-rich water treatment group (HW group, sugar-free medium+10 mmol/L Na₂S₂O₄ treated for 90 minutes and then changed to medium containing hydrogen-rich water for 4 hours). The morphology of HT22 cells was observed by inverted microscopy; cell activity was detected by CCK-8 method; cell ultrastructure was observed by transmission electron microscopy; the expression of microtubule-associated protein 1 light chain 3 (LC3) and Beclin-1 was detected by immunofluorescence; the protein expression of LC3II/I and Beclin-1, markers of cellular autophagy, was detected by Western blotting. RESULTS: Inverted microscopy showed that compared with the NC group, the OGD/R group had poor cell status, swollen cytosol, visible cell lysis fragments and significantly lower cell activity [(49.1±2.7)% vs. (100.0±9.7)%, P < 0.01]; compared with the OGD/R group, the HW group had improved cell status and remarkably higher cell activity [(63.3±1.8)% vs. (49.1±2.7)%, P < 0.01]. Transmission electron microscopy showed that the neuronal nuclear membrane of cells in the OGD/R group was lysed and a higher number of autophagic lysosomes were visible compared with the NC group; compared with the OGD/R group, the neuronal damage of cells in the HW group was reduced and the number of autophagic lysosomes was notably decreased. The results of immunofluorescence assay showed that the expressions of LC3 and Beclin-1 were outstandingly enhanced in the OGD/R group compared with the NC group, and the expressions of LC3 and Beclin-1 were markedly weakened in the HW group compared with the OGD/R group. Western blotting assay showed that the expressions were prominently higher in both LC3II/I and Beclin-1 in the OGD/R group compared with the NC group (LC3II/I: 1.44±0.05 vs. 0.37±0.03, Beclin-1/β-actin: 1.00±0.02 vs. 0.64±0.01, both P < 0.01); compared with the OGD/R group, the protein expression of both LC3II/I and Beclin-1 in the HW group cells were notably lower (LC3II/I: 0.54±0.02 vs. 1.44±0.05, Beclin-1/β-actin: 0.83±0.07 vs. 1.00±0.02, both P < 0.01). CONCLUSIONS Hydrogen-rich water has a significant protective effect on OGD/R-causing HT22 cell injury, and the mechanism may be related to the inhibition of autophagy.
Mice ; Animals ; Oxygen/metabolism* ; Beclin-1/pharmacology* ; Glucose/metabolism* ; Actins ; Sincalide ; Autophagy/physiology* ; Hydrogen/pharmacology* ; Reperfusion Injury ; Apoptosis