Effect of endomorphins on advanced glycation end products-induced expression of nitric oxide and endothelial nitric oxide synthase and endothelin-1 in human umbilical vein endothelial cells

Abstract

Objective To discuss the effects of endomorphins (EMs) on synthesis and secretion of vasoactive substances in human umbilical vein endothelial cells(HUVECs) under advanced glycation end products (AGEs) injury conditions. Methods HUVECs were stimulated with bovine serum albumin(BSA), AGEs-BSA, AGEs-BSA+ EMs (1×10-5, 1×10-6, 1×10-7, and 1×10-8 mol/L), AGEs-BSA+ EMs(1×10-5 mol/L)+ naloxone, respectively. The HUVEC viability was measured by methylthiazolyte-trazolium (MTT) assay, contents of nitric oxide (NO) and endothelial nitric oxide synthase (eNOS) were detected by colorimetric analysis, level of endothelin-1 (ET-1) was detected by enzyme linked immunoabsorbent assay (ELISA), expression of eNOS and ET-1 mRNA was measured by reverse transcription polymerase chain reaction (RT-PCR). Data were analyzed by one-way ANOVA and t test. Results Compared with the cells incubated with AGEs-BSA, the cell viability was significantly enhanced in 1×10-5 mol/L EM1 group (0.89±0.05 vs 0.67±0.02, t=9.86, P 0.05), but significant differences were found between AGEs-BSA+ EMs+ naloxone and EMs groups(t=2.24 to 64.96, all P<0.05). Conclusions EMs has a certain protective effect on AGEs-BSA-induced injury in HUVEC, which can be blocked by naloxone. Key words: Glycation end products, advanced; Endomorphins; Human umbilical vein endothelial cells; Nitric oxide; Endothelin