Effect of Gymnema Sylvestre on Protein Kinase B in Adipose Tissues of Insulin Resistance Mice / 世界科学技术-中医药现代化

ABSTRACT

This article was aimed to study effects and mechanisms of Gymnema sylvestre on protein kinase B (PKB) and its phosphorylation in adipose tissues of KKAy mice which were mainly characterized by insulin resistance (IR). A total of 18 KKAy mice were randomly divided into the diabetes model (DM) group and Gymnema sylvestre (GS) group according to body weight levels. And 9 normal C57BL/6J mice were used as the normal control (NC) group. Intragastric administration of medication was given to mice for 8 weeks. At the end of the experiment, all animals were tested for fasting plasma glucose (FPG) and fasting insulin level (Fins) for evaluation of insulin sensitivity index (ISI). Expressions of phosphoinositide-dependent kinase-1 (PDK1), PKB, P-PKB (Ser473), P-PKB (Thr 308) in adi-pose tissues of epididymis were determined. The expression of phosphatase and tensin homolog (PTEN) mRNA was also determined. The results showed that compared with the DM group, the GS group showed lower FPG and Fins, higher ISI. The expression of P-PKB (Ser473) phosphorylation and P-PKB (Thr 308) were increased, and the PDK1 and PTEN mRNA were decreased. It was concluded that GS can improve insulin sensitivity of KKAy mice through activating PKB by up-regulate the expression of P- PKB (Ser473) and its phosphorylation ratio and P- PKB (Thr 308) in adipose tissues.