The Role Of High Glucose In The Expression Of HMGA1in Human Umbilical Vein Endothelial Cells And The Mechanism

Objective To investigate the effect of high glucose on the expression ofHMGA1mRNA and protein in human umbilical vein endothelial cells(HUVECs) andto unravel the associated mechanism of this process, providing a new idea for thestudy of the pathogenesis of diabetic vascular complications and prevention strategies.Methods Cultured HUVECs were used for the experiment to investigate the effectof high glucose on the expression of HMGA1in HUVECs and to unravel themechanism. The experiment was consisted of two parts：The first part was toinvestigate the effect of high glucose on the expression of HMGA1in HUVECs.Dose-effect experiment was divided into five groups:5.5mmol/L glucose group(control group),11.1mmol/L glucose group,22.2mmol/L glucose group,33.3mmol/Lglucose group, mannitol as osmotic control,each group was treated for24h.Time-effect experiment was divided into five groups:0h group,3h group,6hgroup,12h group,24h group, each group was treated with high glucose at aconcentration of11.1mmol/L. At the end of the experiment, the expression ofHMGA1mRNA and protein was detected by RT-PCR and Western Blot. The secondpart was to unravel the mechanism of the process that high glucose induced the highexpression of HMGA1in HUVECs, the experiment was divided into four groups:control group (5.5mmol/L glucose), high glucose group (11.1mmol/L glucose), highglucose (11.1mmol/L glucose) with Wortmannin (inhibitor of PI3K) group, highglucose (11.1mmol/L glucose) with SP600125(inhibitor of JNK) group. After treatedfor24hours, the expression of HMGA1mRNA and protein of each group wasdetected by RT-PCR and Western Blot.Results HUVECs were treated by different concentrations of glucose for24hrespectively. Compared with control group(5.5mmol/L), the expression ofHMGA1mRNA and protein was increased at the glucose concentrations of 11.1mmol/L group, and22.2mmol/L group,（P<0.05）, and the expression level ofHMGA1is the highest at the concentration of11.1mmol/L glucose group, however,the expression of HMGA1mRNA and protein was showed no significant difference at33.3mmol/L glucose concentration（P>0.05）. Compared with control group (5.5mmol/L), the expression of HMGA1mRNA and protein was increased when treatedwith the concentrations of11.1mmol/L glucose for3h,6h,12h,24h（P<0.05）,and theexpress-ion level of HMGA1is the highest at the concentration of11.1mmol/Lglucose for12h. Compared with the high glucose (11.1mmol/L glucose) group, theexpression of HMGA1mRNA and protein was decreased when the cells were treatedby11.1mmol/L glucose with Wortmannin group and11.1mmol/L glucose withSP600125（P<0.05）.Conclusions (1) The treatment of11.1mmol/L and22.2mmol/L concentration ofglucose could promote the transcription of HMGA1mRNA and increase the proteinexpression of HMGA in the human umbilical vein endothelial cells.(2) The effect ofhigh glucose on the HMGA1gene expression in human umbilical vein endothelialcells might be related to PI3K and JNK signaling pathways.