Protective effect and molecular mechanism of GLP-1 on the high glucose-induced endothelial cell injury

Objective: To study the protective effect and molecular mechanism of glucagon-like peptide-1 (GLP-1) on the high glucose-induced endothelial cell injury. Methods: Endothelial cells HUVECs were cultured and divided into three groups, control group were treated with serum-free low-glucose culture medium, high glucose group were treated with serum-free culture medium containing 40 mmol/L glucose and GLP-1 group were treated with serum-free culture medium containing 10 mmol/L GLP-1 and 40 mmol/L glucose. 24 h after treatment, the expression of apoptosis genes and autophagy genes as well as the levels of oxidative stress products and antioxidants were measured. Results: JAK2, STAT3, Bax, Caspase-9, Caspase-3, Nrf2, NQO1, HO1 and GSH-Px mRNA expression as well as ROS, gp91phox, MDA and ox-LDL levels in high glucose group of cells were significantly higher than those in control group while STSQM1, Atg-5 and LC-3 mRNA expression were significantly lower than those of control group;JAK2, STAT3, Bax, Caspase-9 and Caspase-3 mRNA expression as well as ROS, gp91phox, MDA and ox-LDL levels in GLP-1 group of cells were significantly lower than those in high glucose group while Nrf2, NQO1, HO1, GSH-Px, STSQM1, Atg-5 and LC-3mRNA expression were significantly higher than those in high glucose group. Conclusion:GLP-1 can reduce the high glucose-induced endothelial cell injury by inhibiting apoptosis, reducing oxidative stress and enhancing autophagy.