Research Article

Exercise preserves pancreatic β-cell mass and function in obese OLETF rats

Jiawei Zhao, Zhihong Yang, Min He, Qinghua Wang and Renming Hu*

Published: 06/19/2018 | Volume 2 - Issue 1 | Pages: 022-029

Abstract

Although exercise has been proposed to be beneficial to type 2 diabetes, its effects on β-cell function and mass remain unclear. In the present study, the effects of long-term swimming training on the function and mass of β-cells in diabetic OLETF rats were examined. At 44 weeks of age after developing diabetes, the OLETF rats were divided into two groups: a control group and an exercise group. The exercise group had a daily swimming for 12 weeks. While not found with the control rats, in the obese OLETF rats, the exercise reduced the weight gain which was associated with improved glucose tolerance and elevated circulating insulin levels as determined by the oral glucose tolerance test and insulin ELISA. The exercise improved plasma total cholesterol and triglyceride levels, and also significantly increased the islet β-cell mass and pancreatic insulin content associated with decreased β-cell apoptosis and elevated activation of the serine/threonine kinase, Akt. The present studies suggest that exercise improves diabetes symptoms via enhancement of the β-cell mass and function through decreasing glucolipotoxicity and reducing β-cell apoptosis by activating Akt in obese OLETF rats.

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