Protective effect of glucagon-like peptide-1 analogue on cardiomyocytes injury induced by hypoxia/reoxygenation / 中华内科杂志

ABSTRACT

Objective To investigate the effect of glucagon-like peptide-1 (GLP-1) receptor agonist liraglutide on hypoxia/reoxygenation (H/R)-induced cardiomyocytes death under high glucose condition and the potential mechanisms.Methods H9C2 cardiomyocytes were divided into 4 groupsnormal glucose (N,5 mmol/L),high glucose (G,20 mmol/L),high glucose in combination with liraglutide (L,100 nmol/L),high glucose in combination with liraglutide and wortmannin (W,25 nmol/L).The apoptosis of H9C2 was detected by TUNEL assay.Nitric oxide synthetase(eNOS),nitric oxide (NO) and reactive oxygen(ROS) in supernatants were measured by enzymatic analysis,p-PI3K,PI3K,p-Akt,Akt,Bcl-2,caspase-3 were examined by western blotting.Results Compared with cells in N group,the apoptosis of H9C2 cells induced by H/R was markedly increased [(15.79 ± 3.92) ％ vs (9.74 ± 1.14) ％,P =0.028] in G group.The same was true for ROS [(489.63 ±21.01) U/ml vs (338.50 ±43.60) U/ml,P ＜0.001] and caspase-3 levels (1.87 ±0.03 vs 1.15 ±0.04,P ＜0.001),but not for Bcl-2 protein expression (1.79 ± 0.06 vs 1.89 ±0.03,P =0.047).Pretreatment of cells with liraglutide (100 nmol/L) prevented the cell death induced by high glucose and H/R together with decrease of ROS and caspase-3 levels and increase of Bcl-1 expression.Moreover,treatment of cells with liraglutide also significantly increased phosphorylation of PI3K and Akt (p-PI3K/PI3K0.87 ± 0.07 vs 0.59 ± 0.09,P =0.002;p-Akt/Akt0.34 ± 0.01 vs 0.08 ± 0.01,P＜0.001),eNOS[(41.29 ±0.56) μmpl/L vs (37.20 ±0.52)μxmpl/L,P ＜0.001]and NO [(31.24 ±0.40) μmpl/L vs (26.66 ±0.53) μmpl/L,P ＜0.001] levels.Furthermore,addition of PI3K/Akt inhibitor wortmanin markedly inhibited the expression of p-PI3K/PI3K,p-Akt/Akt,reversed the changes of eNOS,NO,caspase-3 and Bcl-2 by liraglutide,and abolished the protective effect of liraglutide on cell apoptosis.Conclusions GLP-1 receptor agonist liraglutide treatment could alleviate cardiomyoeytes apoptosis induced by high glucose and H/R through the activation of PI3K-Akt-eNOS-NO signaling pathway and inhibition of oxidative stress.