Abstract

Background: Protein tyrosine phosphatase 1B (PTP1B) is a key enzyme in dephosphorylation of the insulin receptor (IR) and it is a central factor to induce the insulin resistance. The purpose of this study was to evaluate the effect of 12-week aerobic training on protein tyrosine phosphatase 1B gene expression and insulin resistance in diabetic rats.

Materials and Methods: In this study, 16 Wistar rats were divided into aerobic training and control groups. After inducing diabetes intra protaneally, aerobic training group performed training protocol for 12 weeks and 5 session/week. The duration and speed of each session increased progressively as 18 to 26 m/min and 10 to 55 min, respectively. Then, blood and tissue (from gastrocnemius) sampling were carried out in diabetic rats. Insulin resistance markers and PTP1B gene expression were evaluated by commercial kits and Real-Time PCR method, respectively.

Results: Findings showed that PTP1B significantly was decreased in diabetic rats of aerobic training group (p=0.0001). Also, glucose and insulin resistance significantly was decreased in aerobic training groups (p=0.02 and p=0.006, respectively). However, insulin in control rats was significantly increased (p=0.015).

Conclusion: It seems that, current aerobic training protocol has capability to decrease PTP1B and insulin resistance in diabetic rats. Furthermore, the direct correlation between PTP1B and insulin illustrated that any changes in insulin resistance due to exercise training associated with diminution of negative regulation of insulin signaling pathway.