OBJECTIVETo study the effect of sour TCM compound Recipe (SCCR) on insulin resistance in experimental rats with diabetes mellitus type 2 (DM2), under the guidance of TCM doctrine of "sour restrains sweet".

METHODSModel rats of DM2 were established by 8 weeks' feeding with high calorie forage combined with intraperitoneal injection of small dose of streptozotocin, and treated with SCCR (15 g/kg of crude drug/day). Levels of fasting blood glucose (FBG), serum insulin, free fatty acids (FFA), tumor necrosis factor a (TNF-alpha), combining capacity and constant of insulin receptor in liver were determined before treatment and 4, 8 and 12 weeks after treatment, and the insulin sensitive index was calculated. The data were compared with those in the model group (untreated), sweet TCM compound recipe group and bitter TCM compound group (treated with sweet and bitter Chinese drugs respectively) and the control group (treated with dimethyldiguanide).

RESULTSSCCR could markedly reduce the FBG, serum FFA and TNF-alpha levels in rat model of DM2, stimulate the secretion of insulin, raise the combining capacity and constant of insulin receptor in liver and improve the insulin sensitivity, as compared with the effect of sweet or bitter Chinese compound recipe, the difference was significant (P < 0.05).

CONCLUSIONSCCR could improve the glucose metabolic disorder and ameliorate the degree of insulin resistance in DM2 model rats, with the effect superior to those with sweet or bitter taste, which illustrates primarily that the therapeutic principle of "sour restrains sweet" of TCM is true of science in a certain degree and having its guiding significance in clinical practice.