Research Article

Rosiglitazone Prevents High Glucose-Induced Vascular Endothelial Growth Factor and Collagen IV Expression in Cultured Mesangial Cells

Figure 1

Effect of high glucose on PPAR expression. Rat glomerular mesangial cells were cultured in 5.6 mM (NG) or 25 mM D-glucose (HG), or 5.6 mM D-glucose 24.4 mM L-glucose (LG) for up to 48 hours. (a) PPAR was detected by immunobloting in total cell lysates, using -actin as the loading controls. The graphs represent PPAR protein levels relative to NG. (b) PPAR mRNA levels were determined by real-time RT-PCR. ( , versus NG; versus NG). (c) Preincubated with 10  M rosiglitazone (RSG) or/and 10  M GW9662, the protein expression of PPAR was not affected by RSG or GW6992 in HG ( versus NG). Mesangial cells were transiently transfected with a luciferase reporter gene containing three PPAR response elements and then cultured in the above conditions. (d) Luciferase reporter activity was reduced in HG ( versus NG, versus NG). (e) In NG, PPAR promoter activity increased in dose response to RSG ( , versus NG). (f) GW6992 blocked the effect of RSG ( , versus NG alone, versus NG or HG alone, versus NG or HG with RSG).