ABSTRACT
Objective To investigate the effects of angiotensin1-7 (Ang1-7) on renal tubulointerstitial fibrosis of diabetic rats.Methods Thirty-two male Wistar rats were randomly divided into four groups: normal control group,diabetic group,telmisartan group,Ang1-7-treated group.For 9 weeks after diabetes mellitus model established,24 h proteinuria,urine NAG/Cr,glucose,insulin,TG,TC,BUN,Scr,Na+ and K+ were assessed.Renal pathological changes were evaluated by PAS staining; Expression of TGF-β1,PPARγ and α-SMA mRNA was deteeted by real-time PCR; Protein levels of PPARγ,α-SMA and TGF-β1 were detected by Western blotting.Results (1)At the end of the ninth week,the blood pressure,proteinuria,renal weight/body weight in group DM were significantly higher than those in group NC (P＜0.05).(2)Renal interstitial fibrosis in group DM was obviously severe as compared to group NC (P＜0.05),but was improved in group TM and group T(P＜0.05).(3)TGF-β1 and α-SMA mRNA in group DM were significantly increased,and PPARγ mRNA was significantly decreased.Compared with group DM,TGF-β1 and α-SMA mRNA were significantly decreased,and PPARγ mRNA was significantly increased in group TM and group T,especially in group T.(4)TGF-β1 and α-SMA in group DM were significantly increased,and PPARγ decreased significantly.Compared with group DM,TGF-β1 and α-SMA decreased significantly,PPARγ increased significantly in group TM and group T,especially in group T.Conclusion Ang1-7 inhibits high glucose-induced α-SMA expression in vivo through up-regulating the PPAR expression and may inhibit renal tubulointerstitial fibrosis of diabetic rats.