[Effects of linggui zhugan decoction combined calorie restriction on the insulin resistance of model rats and mechanisms research].

OBJECTIVE: To explore the effects of Linggui Zhugan Decoction (LZD) combined calorie restriction on fasting plasma glucose (FPG), the insulin resistance (IR), and the peroxisome proliferator-activated receptor gamma (PPAR-gamma) of IR model rats. METHODS: Totally 48 male Wistar rats were randomly divided into the control group, the model group, the calorie restriction group, and the TCM + calorie restriction group, 12 in each group. Ordinary forage was given to those in the control group, and high fat diet was fed to those in the rest 3 groups for 12 weeks to establish the IR model. After successful modeling, rats in the control group and the model group were continually fed with the original farage for 4 days. The normal saline at the daily dose of 20 mL/kg was given to them by gastrogavage. The normal saline at the daily dose of 20 mL/kg was given to rats in the calorie restriction group by gastrogavage after 4-day calorie restriction. LZD at the daily dose of 20 mL/kg was given to rats in the TCM +calorie restriction group by gastrogavage after 4-day calorie restriction. The body weight, FPG, serum fasting insulin (FINS), insulin resistance index (IRI), and the protein expression of PPAR-y in the omental adipose tissue were compared. RESULTS: After 4-day calorie restriction, the body weight obviously decreased in the calorie restriction group and the TCM +calorie restriction group, when compared with the model group (P <0.01). There was no statistical difference between the former two groups (P >0.05). The FINS and IRI obviously decreased in the calorie restriction group (P <0.01, P <0.05). The FPG, FINS, and IRI significantly decreased in the TCM + calorie restriction group (P <0. 05, P <0.01). The protein expression of PPAR-gamma obviously decreased in the calorie restriction group and the TCM + calorie restriction group (P <0.01).The phlegm dampness state was alleviated, with more significant effects shown in the TCM + calorie restriction group. CONCLUSIONS: LZD combined calorie restriction could reduce the body weight, FPG, and IRI of IR rats. Besides, it showed better effects than calorie restriction alone. Its effects in improving IR might be correlated with inhibiting the activities of PPAR-gamma. Meanwhile, it might play a role in inhibiting the differentiation of fat cells.