The protective effects of bovine colostrum truncated IGF-1 on kidney of diabetic rats and the study of mechanism

Objective To observe the effect of BCtIGF-1 on diabetic nephropathy and explore its mechanism. Methods Techniques including biochemistry, radioimmunoassay, fluoroassays, molecular biology(HT-PCR) were used in this study. Results (1) Serum FBG, TG and FMN concentrations in BCtIGF-1 groups were significantly lower than those of diabetic control group; (2) 24h UAER, 24h urinary volume in BCtIGF-1 groups were significantly lower than those of diabetic control group; (3) BCtIGF-1 had protective effect on diabetic nephropathy by observing the kidney tissues with electron microscope; (4) Kidney IGF-1mRNA in diabetic control group was significantly lower than that of normal control group, no differences were found between diabetic control group and BCtIGF-1 groups; (5) Collagen and AGEs of kidney tissue, urinary TXB2/6-keto-PGF1a in BCtIGF-1 groups were significantly lower than those of diabetic control group; Conclusions (1) BCtIGF-1 has hypoglybemic and hypolipidic effects; (2) BCtIGF-1 does not increase the level of IGF-1mRNA in kidney tissue; (3) BCtIGF-1 might have protective effect on diabetic nephropathy. The protective mechanism may be associated with its hypoglycemic and hypolipidic effects; in addition, it might relate to the improvement of PGI2-TXA2 synthetic imbalance and the reduction of the collagen and AGEs levels in kidney tissue.