Role and related mechanism of Mst-1 on regulating hypoxic reoxygenation induced autophagy and apoptosis in cardiomyocytes of mouse.
10.3760/cma.j.cn112148-20201102-00873
- Author:
Yan WANG
1
;
Ran Zun ZHAO
1
;
Zhi Mei QIU
1
;
Chang Yin SHEN
2
;
Pan Ke CHEN
1
;
Xing HAO
1
;
Jin Song YUAN
1
;
Wen Wen DENG
1
;
Bei SHI
1
Author Information
1. Department of Cardiology, Affiliated Hospital of Zunyi Medical University, Zunyi 563000, China.
2. Department of Cardiology, Second Affiliated Hospital, Zunyi Medical University, Zunyi 563000, China.
- Publication Type:Journal Article
- Keywords:
Apoptosis;
Autophagy;
Mammalian sterile 20-like kinase 1;
Myeloid cell lekemia-1;
Myocytes, cardiac
- MeSH:
Animals;
Apoptosis;
Autophagy;
Hypoxia;
Mice;
Myocytes, Cardiac;
Signal Transduction
- From:
Chinese Journal of Cardiology
2020;48(12):1060-1069
- CountryChina
- Language:Chinese
-
Abstract:
Objective: To explore the role and related mechanism of mammalian sterile 20-like kinase 1(Mst-1)in regulating hypoxia reoxygenation (HR) induced myocardial cell autophagy and apoptosis. Methods: Enzyme digestion method combined with differential adherent method was used to culture neonatal mouse myocardial cells. HR model was established by hypoxia for 24 hours and reoxygenation for 6 hours. The experimental groups including control group (normal cultured cardiomyocytes), Mst-1 empty virus group (cardiomyocytes transfected with recombinant lentiviral empty vector for 48 hours), Mst-1 knockdown group (recombinant lentivirus carrying Mst-1small interfering RNA (siRNA) was transfected into cardiomyocytes for 48 hours), Mst-1 overexpression group (cardiomyocytes were transfected with recombinant lentivirus carrying Mst-1 gene for 48 hours), HR group (cardiomyocytes exposed to HR), Mst-1 knockdown+HR group (HR model of cardiomyocyte was established 48 hours after transfection with recombinant lentivirus carrying Mst-1siRNA) and Mst-1 overexpression+HR group (HR model of cardiomyocyte was established 48 hours after transfection with recombinant lentivirus carrying Mst-1 gene). Real-time fluorescence quantitative RCR (qPCR) and Western blot were used to detect the relative expression of Mst-1 mRNA and protein in the cells, immunofluorescence staining was used to detect cardiomyocyte troponin T (cTnT), and autophagosomes and autophagy enzyme changes. TUNEL method was used to detect myocardial cell apoptosis, Western blot was adopted to detect autophagy-related protein microtubule-related protein 1 light chain 3 (LC3) Ⅱ/LC3 Ⅰ, P62 and apoptosis-related protein cleaved-caspase 9, pro-caspase 9, cleaved-caspase-3, pro-caspase-3, and myeloid leukemia 1 (MCL-1) expression. MCL-1 inhibitor A1210477 was used to validate the signaling pathway of Mst-1 on regulating cardiomyocyte apoptosis and autophagy. Results: Immunofluorescence detection revealed that the cultured cells expressed cardiomyocyte-specific marker cTnT. The expression of Mst-1 in cardiomyocytes increased in HR model. Lentiviral transfection could effectively inhibit or overexpress Mst-1 in treated cells. The levels of autophagosomes and autophagolysosomes in cardiomyocytes undergoing HR and in Mst-1 overexpression+HR group were lower than those of control group, while autophagosomes and autophagolysosomes in cardiomyocytes of Mst-1 knockdown+HR group was significantly higher than in the HR group (all P<0.05). The TUNEL results showed that the proportion of TUNEL positive cells was significantly increased in the HR group and Mst-1 overexpression+HR group than in the control group, while the proportion of TUNEL positive cells was significantly decreased in the Mst-1 knockdown group+HR group as compared to the HR group (all P<0.05). Western blot results showed that the LC3 Ⅱ/LC3 Ⅰ levels were significantly lower, while the expression levels of P62, cleaved-caspase-9 and cleaved-caspase-3 were significantly higher in the HR group and Mst-1 overexpression+HR group than in control group (all P<0.05). The LC3 Ⅱ/LC3 Ⅰ value was significantly higher, and the expression levels of P62, cleaved-caspase-9 and cleaved-caspase-3 were significantly lower in the Mst-1 knockdown+HR group than in the HR group (P both<0.05). The expression level of P-MCL-1 protein was significantly lower in cardiomyocytes of HR and Mst-1 overexpression+HR group than in control group, and the expression level of P-MCL-1 protein was higher in Mst-1 knockdown+HR group than in HR group (P both<0.05). The recovery experiment showed that inhibiting MCL-1 in cells can block the regulatory effect of Mst-1 siRNA on cell autophagy and apoptosis. Conclusion: Inhibiting Mst-1 expression in cardiomyocytes can promote the autophagy of cardiomyocytes induced by hypoxic reoxygenation and reduce the apoptosis of cardiomyocytes via activating McL-1.