Effect Of Hyperglycemia On Oxidative Stress And Proliferation And The Antioxidant Mechanism Of Resveratrol & Effects Of Tongluo Recipe On Proliferation And Oxidative Stress Of Rat Glomerular Mesangial Cells Under High Glucose

Hyperglycemia induced oxidative stress has been implicated in diabetic microvascular complications in which NADPH oxidase is a major source of reactive oxygen species (ROS) generation. Resveratrol is a naturally occurring polyphenol which has microvasoprotective effects in diabetic animal models and inhibits high glucose-induced oxidative stress in glomerular mesangial cells. However, the effect of resveratrol of high glucose-induced NADPH oxidase activation and ROS production of glomerular mesangial cells are not clear. By using a rat glomerular mesangial cell line(RMC,ATCC Number:CRL-2573TM ) and primary rat mesangial cells, we found that resveratrol reversed high glucose-induced proliferation of mesangial cell viability through inhibition of NADPH oxidase activition and ROS production. Mechanistic studies showed that high glucose enhanced NADPH oxidase acticity and ROS production in mesangial cells through upregulation of p22^phox and p47^phox but not Nox4. High glucose also upregulated Fibronectin and Collagen IV mRNA and protein levels. Resveratrol significantly inhibited p22^phox and p47^phox upregulation , NADPH oxidase activation and Fibronectin and Collagen IV upregulation by high glucose. Further studies showed that resveratrol suppressed p22^phox , p47^phox , Fibronectin and Collagen IV upregulation through inhibition of JNK and NF-κB activation by high glucose. Taken together, these results demonstrate that resveratrol protect glomerular mesangial cells from hyperglycemia-induced proliferation through inhibiting activation of JNK/NF-κB/p22^phox and p47^phox/NADPH /ROS pathway by high glucose, and suggest the potential for new treatment approaches targeting mesangial JNK/NF-κB/ NADPH oxidase signaling pathway in renal microvascular complications of diabetes. To investigate the effects of Tongluo Recipe (TLR) on proliferation and oxidative stress of rat glomerular mesangial cells under high glucose, Rat mesangial cell lines (rat mesangial cells ,RMCs) under high glucose condition were treated with TLR. The proliferation of mesangial cells was detected by MTT assay.The reactive oxygen was detected by DCFH-DA probes. The expression of mRNA of CuZnSOD, CAT, Gpx, MnSOD and FN were detected by RT-PCR and the protein of MnSOD and FN were detected by Western blot. Tongluo Recipe significantly decreased the proliferation and ROS of rat mesangial cells under high glucose (P<0.05). Tongluo Recipe could increase the protein level of MnSOD under normal glucose conditions and decrease the protein level of Fibronectin (FN) in a dose-dependent manner. So the Tongluo Recipe could inhibit the proliferation, inhibit the generation of ROS and improve the antioxidative enzymes capacities of rat glomerular mesangial cells under high glucose.