Study On Genes In Early Diabetic Nephropathy Using Tangshenkang

OBJECTIVE Diabetic nephropathy is a major complication which affects people' health and life quality severely, and a leading cause of renal failure. So far, several hypotheses have been postulated for its development. Tangshenkang is one kind of multiple-herbs and our previous studies show that it not only strengthens kidney but also activates the renal blood circulation .And it is clinically effective for early diabetic nephropathy . Then to explore the genetic changes of diabetic rats and the protective effects of Tangshenkang by DNA microarray.MATERIALS AND METHODS Male Sprague Dawley (SD) rats were intrapertoneal ly injected with STZ at the dose of 55mg · kg^-1 to get the diabetic model rats. Then diabetic rats were divided randomly into two groups: diabetic group (n=16) and Tangshenkang-treated group ( 75mg · kg^-1 · d^-1 n=14) .All rats were fed freely, with blood glucose, HbA₁c, body weight examined. Twelve weeks later, microalbuminuria of 24 hours (24h-UMA) were tested and then all rats were sacrificed and kidney/body weight were measured. Next, the mRNA of kidney was immediately extracted from three groups (normal rats, diabetic rats, Tangshenkang - treated rats ) , and reversely transcribed to cDNA with the incorporation offluorecent-marked dUTP such as Cy3 or Cy5, and then hybridized with a DNA microarray . The fluorecent signals of Cy3^ Cy5 were scanned and analysised.RESULTTS (l)Compared with normal group, diabetic rats showed significant increase of blood glucose . And there is no change between diabetic rats and Tangshenkang -treated rats. (2) The levels of HbAiC in diabetic rats were higher than in normal rats (p<0.05).And Tangshenkang can not decrease the levels of HbA,c. (3) There was significant increase of 24h-(JMA in diabetic rats compared with the normal rats. And Tangshenkang can sharply decrease it (p<0.05). (4) There was significant increase of the kidney/body weight in diabetic rats compared with normal rats. And Tangshenkang can not alleviate kidney hypertrophy. (5) Expression of DNA microarray : Compared with normal rats, diabetic rats had up-regulated genes such as FGB,IGFBP-3 and other down -regulated genes such as PTGDS, EGF, CYP11A. And Tangshenkang -treated rats had up-regulated genes such as ILK, down-regulated genes such as PMP22, IGF1, CYP1A1, compared with diabetic rats.CONCLUSIONS (1)Tangshenkang can delay the development of diabetic nephropathy by decreasing 24h^UMA. (2)The difference of genetic expression, provides further experimental evidence about mechanism of diabetic nephropathy and the protection effect of Tangshenkang.