Protective effect of compound K on diabetic rats.

Purpose Compound K (CK), the metabolic product of protopanaxadiol saponin in vivo, has many pharmacological activities. In this study, we discuss the preparation of CK, and its protective effect on kidneys of diabetic rats. CK was prepared from ginsenoside Rb-1 after transformation by beta-glucosidase, separation and purification by silica gel column chromatography. In the present study, we established a rat model of diabetes mellitus using high-fat diet and streptozotocin (STZ). After seven weeks of treatment, the levels of fasting blood glucose (FBG), total cholesterol (TC), total glycerin (TG), high-density lipoprotein (HDL-C), low-density lipoprotein (LDL-C), blood urea nitrogen (BUN), uric acid (UA), serum creatinine (Scr), malondialdehyde (MDA), glutathione (GSH), and superoxide dismutase (SOD) activity and glutathione peroxidase (GSH-PX) were evaluated in normal and diabetic rats. Also, renal pathomorphism changes were observed by HE stain, and TGF-beta(1) protein expression in the renal tissue was measured by Western blot. The yield of CK was 14.55 mg/mL, which was higher than that of other methods. After seven weeks, CK could decrease FBG, TC, TG, LDL-C, BUN, UA, Scr and MDA of diabetic rats, while CK also enhanced HDL-C and GSH, SOD and GSH-PX. Additionally, CK improved the pathological changes and decreased TGF-beta(1) protein expression in the renal tissue. CK improved the pathological changes in the renal tissue, enhanced the antioxidant capacity, reduced the damage of TGF-beta(1) to renal tissue, and protected the diabetic rats.