The influence of microRNA-21 expression in vascular endothelial cells treated with high glucose and insulin.

Objective To explore the expression and function of miRNA-21 and programmed cell death 4 (PDCD4) in Human umbilical vein endothelial cells (HUVECs) treated with high glucose or insulin.Methods: HUVECs were treated with D-Glucose in different concentrations (5.5mM,11 mM,22 mM and 33 mM) or insulin (0nM,1nM,10nM,50nM,100nM,1000nM) respectively for 2 days,and then cells were collected to detect miRNA-21 and PDCD4 mRNA expression levels with the real-time fluorescence quota RT-PCR method.The expression of protein PDCD4 in HUVECs were determined by Western blot analysis.Results: To compare with the control group of 5.5 mM glucose ,miRNA-21 expressions in 11 mM,22 mM and 33 mM groups were down-regulated significantly along with the increasing of glucose concentrations (p 0.01).PDCD4 protein expression were increased(p 0.05),but no difference of PDCD4 mRNA expression was observed among four groups (p0.05).To compare with the control group of 0nM insulin ,miRNA-21 expression were down-regulated in high insulin groups (10nM,50nM,100nM and 1000nM) and miRNA-21 expression was reduced most significantly in 1000 nM insulin group (p 0.05).PDCD4 protein expressions were up-regulated in high insulin groups (10nM,50nM,100nM and 1000nM) (p 0.01),but no difference of PDCD4 mRNA expression was observed among groups (p 0.05).Conclusions: The expression of miRNA-21 and PDCD4 protein were influenced in vascular endothelial cells treated by high glucose or high insulin and the signal transduction pathways involving in miRNA-21 and PDCD4 possibly participated in the process of apoptosis in vascular endothelial cells treated by high glucose or high insulin.