Effects of Interval training on expression of G6Pase gene in hepatocyte of Streptozotocin-Nicotinamide induced Type-2 diabetic male rats
Effects of Interval training on expression of G6Pase gene in hepatocyte of Streptozotocin-Nicotinamide induced Type-2 diabetic male rats
Samin Khalilzadeh Kouchameshki,1Mehri Ghahramani Dereshki,2,*
1. 11th grade student, Farzangan Selmas Girls High School, West Azarbaijan, Selmas, Iran. 2. Associate Prof, Department of Exercise Physiology, Tabriz Branch, Islamic Azad University, Tabriz, Iran.
Introduction: Insulin dysfunction or inadequate insulin secretion leads to type 2 diabetes (1). About 90% of these patients are type 2 diabetic ones (2, 3). According to the World Health Organization, there has been a global increase in the number of people with diabetes from 108 million to 442 million in the past decade (4).
One way to maintain glucose homeostasis is to regulate hepatic gluconeogenesis. Suppression of gluconeogenesis by controlling the expression of genes affecting it is one of the methods to restore normal blood glucose levels for the treatment of type 2 diabetes (6). PGC-1α gene is downstream intracellular genes involved in gluconeogenesis that regulate the expression of enzymes such as G6Pase. Glucagon regulates the expression of PGC-1α (7), thereby controlling the transcription of gluconeogenic enzymes such as G6Pase.
G6Pase is one of the key enzymes involved in gluconeogenesis that converts glucose 6 phosphate to glucose. The presence of this enzyme allows the tissue to release glucose into the blood (8). Insulin inhibits PGC-1α activity(7).
Physical activity is an effective strategy in improving type 2 diabetes (9 However, further studies are needed to evaluate in detail the relative effect of exercise (10). G6Pase is an important insulin signaling gene in liver and involved in diabetes, studies have shown that the role of G6Pase is influenced by PGC-1α in regulating type 2 diabetes (14); thus better understanding the role of G6Pase may open a clear horizon for an effective therapeutic strategy.
However, the pathways of hepatic gluconeogenesis signaling in diabetics in response to different types of exercise with varying intensity and duration are not completely clear, and studies at the level are not sufficient. Therefore, identifying the effect of exercise training on hepatic gluconeogenesis in diabetic patients and how to regulate the genes involved in it, is an undeniable necessity to find a milestone in helping to reduce diabetes complications. In the present study, the effect of 10 weeks of Interval training on the expression of G6Pase gene in the liver of streptozotocin-induced diabetic rats was investigated.
Methods: In This study was performed in an experimental design on 16 diabetic male Wistar rats (mean weight, 220±20 g). After type 2 diabetes induction (with nicotinamide-streptozotocin), the samples were divided into two groups of Interval and Controlled. The training program was 10 weeks and five times a week, with a gradual increase in speed. 48 hours after the last training session, liver tissue samples were taken after an overnight fast. Fasting glucose, serum insulin, insulin resistance, G6Pase gene expression in hepatocyte were measured in both groups. The obtained data were compared using independent t-test. The significance level was considered to be p<0.05.
Results: Independent t-test showed that 10 week Interval training significantly decreased the fasting glucose (P-value< 0.001) and increased serum insulin (P-value< 0.001). But, the changes in insulin resistance (p=0.266), the expression of G6Pase (p=0.492) were not significant in the exercise group compared to the control group.
Conclusion: The results of the present study showed that 10 weeks of interval exercise can significantly decrease fasting glucose and increase blood insulin and this regulation and control of glycemia and improvement of blood glucose and insulin levels without affecting the expression of G6Pase gene have expressed. Therefore, further studies are needed to align different genes and their complex relationship to the pathway of hepatic gluconeogenesis under the influence of different types of exercise. According to the results of this study, which indicated a decrease in fasting glucose and an increase in serum insulin, it can be concluded that interval exercise may be used as a non-pharmacological treatment to improve type 2 diabetes. However, given the limited research on the cellular and molecular domain of diabetes and exercise training, and because of the limited scope of the present study, further laboratory and field studies are needed to elucidate other mechanisms that may be involved. Future research to understand the mechanisms involved in all types of exercise with a glycemic control approach may provide new avenues for regulating insulin sensitivity in people with type 2 diabetes.
Keywords: Interval exercise, G6Pase, Type 2 diabetic, Streptozotocin