Effect Of Astragalus Injection On The Expression Of BMP-7 And CTGF In Renal Tissues Of Rats With Diabetes Mellitus

Objective:To investigate the influence of astragalus injection on the expression of bone morphogenetic protein-7 (BMP-7) and connective tissue growth factor (CTGF) in kidney tissues of rats with diabetes mellitus. And to discuss the effect of astragalus injection on diabetic nephropathy and the underlying mechanisms involved.Methods:Healthy male Wistar rats (30 samples) with body weight from 200 gram to 250 gram were randomly divided into two groups:8 rats were selected as normal control group fed with normal food, other 22 rats as diabetes mellitus group were fed with high carbonhydrate and high fat diet for 6 weeks and then were injected intraperitoneally with streptozotocin (STZ 30 mg/kg). A total of 20 diabetes mellitus rats model were established. The diabetes mellitus rats were randomly divided into two groups that is diabetes mellitus model group (10 samples) and astragalus injection treated group (10 samples). Rats in astragalus injection treated group were administrated intragastrically with astragalus injection (10g/kg/d). Rats in other groups were treated with intragastric administration of tales doses physiological saline. All rats were treated correspondly for 8 weeks. The urinary albumin excretion rate(UAER) was detected by radio-immunity method. The changes of blood glucose were detected during the treatment period. Triglyceride (TG) and total cholesterol (TC) in blood were measured by automatic biochemistry analyzer. The expression of BMP-7 and CTGF mRNA in renal tissues were detected by RT-PCR. The expression of BMP-7 and CTGF protein in renal tissues were detected by immunohistochemistry assay.Results:Compared with normal control group, the enhancement of blood glucose, TG, TC, kidney weight/body weight and UAER were found in diabetic group(P<0.01), which were significantly ameliorated in treated group with astragalus(P<0.01 or P<0.05)except the blood glucose level. In renal tissues of DM model group, the expression of BMP-7 protein and BMP-7 mRNA were decreased; the expression of CTGF protein and CTGF mRNA were increased significantly compared with normal contronl group(P<0.01). However, in comparison with DM model group, the expression of BMP-7 and BMP-7 mRNA were increased and the expression of CTGF and CTGF mRNA were significantly decreased(P<0.01 or P< 0.05) in Astragalus injection treated group.Conclusion:Astragalus injection could be used to treat diabetic nephropathy, the mechanism of which may be related to up-regulating the expression of BMP-7 and down-regulating the expression of CTGF in renal tissues.