Kudzu root (Ge-Gen) regulates on glucose and lipid metabolism to ameliorating insulin resistance on 3T3-L1 adipocytes / 中国中药杂志

ABSTRACT

This study aimed to explore the mechanism of Chinese traditional medicine, Kudzu root(Chinese name：Ge-Gen; Latin name： Puerariae Lobatae Radix) how to improving insulin resistance (IR) through the regulation of the glucose and lipid metabolism in the IR-3T3-L1 adipocytes. After the 3T3-L1 mouse preadipocytes were differentiated into mature adipocytes, IR model(IR-3T3-L1) was built with 1 μmol•L-1 dexamethasone treatment for 96 h. IR adipocytes were treated with different concentrations (5%,10% and 15%) of Ge-Gen containing serum (GG-CS)for 12 h or 24 h, whereas rosiglitazone group as positive control in this study. The glucose contents in cell culture supernatants were detected by glucose oxidase assay and the intracellular triglyceride (TG) contents were measured by glycerol phosphate oxidase assay respectively.The mRNA expression levels of PPARγ, ADPN, GLUT4, LPL, FABP4 and FASn gene were determined by real-time quantitative PCR(qPCR).Results showed that IR-3T3-L1 adipocytes significantly increased glucose consumption (P<0.01)and decreased TG contents (P<0.01) as compared with the normal control group, the glucose consumption significantly increased with the treatment of GG-CS (P<0.01) by dose-dependent and time-dependent manners,whereas the intracellular TG content was sigificantly decreased (P<0.01) by dose-dependent manner.qPCR analysis revealed that 10% and 15% GG-CS significantly up-regulated the mRNA expression level of PPARγ, ADPN and GLUT4 (P<0.01) with the same dose-dependent manner,whereas the GLUT4 mRNA expression was showed similar expression pattern with the treatment of 10% and 15% GG-CS (P<0.01).We also detected the mRNA expression levels of several important lipid-metabolizing enzymes such as LPL, FASn and FABP4 by PPARγ regulation. 15% GG-CS elevated LPL mRNA expression (P<0.05);10% and 15% GG-CS enhanced the FASn mRNA expression (P<0.01), whereas 5%,10% and 15% GG-CS down-regulated FABP4 mRNA expression (P<0.01). Together, our results indicated that GG could regulate the glucose and lipid metabolism to ameliorate IR with multi-target manners in 3T3-L1 adipocytes.