Glucagon-like peptide-1 protects against cardiac microvascular endothelial cells injured by high glucose

ABSTRACT

Objective:To investigate the protective effect of glucagon-like peptid-1(GLP-1) against cardiac microvascular endothelial cell(CMECs) injured by high glucose.Methods:CMECs were isolated and cultured.Superoxide assay kit and dihydroethidine(DHE) staining were used to assess oxidative stress.TUNEL staining and caspase3 expression were used to assess the apoptosis ofCMECs.H89 was used to inhibit cAMP/PKA pathway; fasudil was used to inhibitRho/ROCK pathway.The protein expressions ofRho,ROCK were examined byWestern blot analysis. Results:High glucose increased the production ofROS, the activity ofNADPH, the apoptosis rate and the expression level ofRho/ROCK inCMECs, whileGLP-1 decreased high glucose-induced ROS production, theNADPH activity and the apoptosis rate and the expression level ofRho/ROCK inCMECs, the difference were statistically significant(P<0.05).Conclusions:GLP-1 could protect the cardiac microvessels against oxidative stress and apoptosis.The protective effects of GLP-1 are dependent on downstream inhibition ofRho through a cAMP/PKA-dependent manner, resulting in a subsequent decrease in the expression ofNADPH oxidase.