Role of PTEN in diabetes mellitus-induced reduction of hypoxic postconditioning-induced protection of cardiomyocytes: the relationship with GSK-3β-mediated mitochondrial apoptotic pathway
10.3760/cma.j.issn.0254-1416.2017.01.026
- VernacularTitle:PTEN在糖尿病因素削弱缺氧后处理对心肌细胞保护效应中的作用:与GSK-3β介导的线粒体凋亡途径的关系
- Author:
Rui XUE
;
Zhongyuan XIA
;
Shaoqing LEI
;
Bo ZHAO
;
Qingtao MENG
;
Wei LI
;
Bin ZHOU
- Keywords:
Glycogen synthase kinase 3;
Anoxia;
Diabetes mellitus;
Myocytes,cardiac;
Reperfusion injury;
Post-conditioning;
PTEN
- From:
Chinese Journal of Anesthesiology
2017;37(1):108-111
- CountryChina
- Language:Chinese
-
Abstract:
Objective To evaluate the role of phosphatase and tensin homologue deleted on chromosome 10 (PTEN) in diabetes mellitus-induced reduction of hypoxic postconditioning (HPO)-induced protection of cardiomyocytes and the relationship with glycogen synthase kinase-3β (GSK-3β)-mediated mitochondrial apoptotic pathway.Methods H9c2 cells incubated in high-glucose (30 mmol/L) medium for 24 h were divided into 6 groups (n =5 each) using a random number table:normoxia group (group N),hypoxia-reoxygenation (H/R) group,group HPO,PTEN gene silencing normoxia group (group P-N),PTEN gene silencing H/R group (group P-H/R),and PTEN gene silencing HPO group (group P-HPO).H9c2 cells were exposed to 95％ N2-5％ CO2 for 4 h followed by 2 h reoxygenation with 90％ O2-10％ CO2.HPO was induced by 3 cycles of 5 min reoxygenation followed by 5 min hypoxia before reoxygenation.At the end of reoxygenation,the level of lactate dehydrogenase (LDH) in the supernatant was detected by enzyme-linked immunosorbent assay,the changes in mitochondrial membrane potential (MMP were assessed by JC-1 fluorescence assay,the cell apoptosis was detected by AnnexinV-FITC/PI flow cytometry,and the expression of PTEN and phosphorylated GSK-3β (p-GSK-3β) was determined by Western blot.The JC-1 monomer/polymer ratio and apoptosis rate were calculated.Results Compared with group N,the amount of LDH released,JC-1 monomer/polymer ratio and apoptosis rate were significantly increased,and the expression of PTEN was up-regulated in H/R and HPO groups (P＜0.05).There was no significant difference in the parameters mentioned above between group H/R and group HPO (P＞0.05).Compared with group HPO,the amount of LDH released,JC-1 monomer/polymer ratio and apoptosis rate were significantly decreased,PTEN expression was down-regulated,and the expression of p-GSK-3β was up-regulated in group P-HPO (P＜0.05).Compared with group N,the expression of PTEN was significantly down-regulated,and no significant changes were found in the other parameters mentioned above in group P-N (P＞0.05).Compared with group H/R,the expression of PTEN was significantly down-regulated,and no significant changes were found in the other parameters mentioned above in group P-H/R (P＞0.05).Conclusion PTEN is involved in diabetes mellitus-induced reduction of HPO-induced protection of cardiomyocytes,and the mechanism is associated with PTEN-induced activation of GSK-3β-modulated mitochondrial apoptotic pathway.
