Effects of aminoguandine and puerarin on expression of connective tissue growth factor in kidneys of diabetic rats

Objective To investigate whether connective tissue growth factor (CTGF) is involved in pathogenesis of diabetic nephropathy and determine consequently whether aminoguanidine (AG) and puerarin(Pue)can attenuate enhanced CTGF expression in kidneys of streptozotocininduced diabetic rats. Methods Expression of mRNA and protein of CTGF in kidney of diabetic rat were quantified by RTPCR with GAPDH as an internal standard and histochemistry demonstrated by monoclonal antibodies against CTGF,respectively. Results It was shown that expression of CTGF/GAPDH mRNA ratio was markedly enhanced in kidney of diabetic rat(0.44±0.03) compared with control group(0.16±0.02). After treatment,AG group ( 0.23±0.02) and Pue group (0.22±0.02) lowed down CTGF expression in kidneys of streptozotocin induced diabetic rats,but still with higher expression level than control group. Immunochemistry showed that positive particles per glomerular increased in diabetic group compared with control group,which could be partly decreased by treatment of AG and Pue. Conclusion The results suggest that CTGF plays a role in diabetic nephropathy. Pue and AG might be of clinical significance in preventing diabetic nephropathy from developing by alleviating increased expression of CTGF.