Effects of food restriction and/or aerobic exercise on the GLUT4 in type 2 diabetic male rats

Abstract

Background: The aim of present study was to compare the effects of negative energy balance with food restriction and/or aerobic exercise on the glucose, insulin, and GLUT4 levels in diabetic male rats.

Methods: Fifty‑six 10‑week old male Wistar rats were randomly assigned to seven groups: a non‑diabetic (ND) group and six diabetic groups. After an infusion of type 2 diabetes, the diabetic groups were given labels as well, namely diabetic control (DC) group, exercise (Ex) group, food restriction with standard diet (FRSD) group, food restriction with low‑carbohydrate diet (FRLCD) group, food restriction with standard diet combination in exercise (FRSDE)
group, and food restriction with low‑carbohydrate diet combination in exercise (FRLCDE) group. Further, to induce caloric restriction (CR), food intake was reduced by 20% and given to food restriction consists of both of (FRSD and FRLCD). Hundred percent food consumption for the Ex group was fixed, but instead, 20% of their energy intake in exercise was calculated, and time of daily exercise was determined. Finally, a combination of reduced food intake (10%)
and exercise (10%) was applied in each group FRSDE and FRLCDE for 8 weeks.

Results: The results showed that type 2 diabetes inductions had reduced glucose, insulin, and GLUT4 gene expression compared to the ND group (P = 0.001). However, there were significant differences in GLUT4 gene expression between groups after 8 weeks of intervention (P = 0.001). A post hoc least significant difference test show that compared to DC group, GLUT4 gene expression level of Ex, FRSDE, and FRLCDE groups was significantly increased 47% (P = 0.004), 60% (P = 0.001), and 65% (P = 0.001), respectively after 8 week of intervention, but it was not significant or with any other diabetic groups (P > 0.05). Moreover, glucose levels were significantly higher in the FRLCDE, FRLCD, FRSD, FRSDE, Ex groups compared with the DC group in the same
period (P = 0.0.01).

Conclusions: It was concluded that FRSD and FRLCD combination in regular exercise was elevated of GLUT4 gene expression in type 2 diabetes. These results may help to develop new methods for the treatment of obesity and type 2 diabetes mellitus.

Keywords: GLUT4 gene expression, low-carbohydrate diet, standard diet, type 2 diabetes