Effect of Exercise on Pancreatic Islets in Zucker Diabetic Fatty RatsSonia Rawal1, Han-Hung Huang2, Lesya Novikova1, Tyler Hamedi1, Irina V Smirnova1 and Lisa Stehno-Bittel1*
- *Corresponding Author:
- Lisa Stehno-Bittel
Department of Physical Therapy and Rehabilitation Science
MS 2002, University of Kansas Medical Center
Kansas City, KS 66160, USA
E-mail: [email protected]
Received date June 10, 2013; Accepted date July 09, 2013; Published date July 14, 2013
Citation: Rawal S, Huang HH, Novikova L, Hamedi T, Smirnova IV, et al. (2013) Effect of Exercise on Pancreatic Islets in Zucker Diabetic Fatty Rats. J Diabetes Metab S10:007. doi:10.4172/2155-6156.S10-007
Copyright: © 2013 Rawal S, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Exercise and physical activity improve the glycemic control in people with type 2 diabetes (T2D). It is known that activity improves muscle utilization of glucose, and that exercise can spare islets if initiated prior to the onset of diabetes. However, any effect of exercise on pancreatic islet function after the diagnosis of overt diabetes is unknown. The aim of the study was to investigate the effects of exercise training on pancreatic islets in a rodent model of overt T2D. 12-week old male Zucker Diabetic Fatty (ZDF) rats and control lean rats were divided into 4 groups: sedentary control exercised control, sedentary diabetic and exercised diabetic. Exercised rats were trained with moderate intensity running on a treadmill for 7 weeks. Assessment of plasma insulin levels, islet cell composition (relative proportion of α, β and δ cells), islet density, insulin content and islet core diameter was conducted at the end of the study. Diabetes in ZDF rats lead to high HbA1c and BGLs, which was not reversed by exercise. Diabetes caused destruction of the islet structure and significant loss of β-cells, with an increased proportion of α- and δ-cells. Exercise improved islets morphology in the diabetic group, while islet density and islet cell composition were not affected by exercise. Increased insulin immunostaining of the pancreatic islets was identified in the diabetic animals after exercise. Although exercise did not affect the diabetes-induced decrease in the proportion of islet β cells, there appeared to be an improvement in the islet architecture and in β-cell insulin content.