Effect of 8 weeks high-intensity interval training on the stress of liver endoplasmic reticulum in obese rats with type 2 diabetes

Recent research has shown that stress of endoplasmic reticulum (ER) in liver tissue plays a significant role in development of type 2 diabetes. The aim of this study was to investigate the effect of 8 weeks high-intensity interval training on two known markers of liver ER stress in rats with type 2 diabetes.

Twenty four male Wistar rats (8 weeks age and 200-250 g weight) were used. The "healthy control" group (8 mice) had free access to standard food and drinking water for 13 weeks. Another 16 mice were fed a high-fat diet for 4 weeks. Then these 16 rats were made diabetic with streptozotocin and allocated in two groups: "diabetic control" (maintenance of a high-fat diet for 9 weeks without exercise) and "diabetic exercise" (maintenance of a high-fat diet, one week familiarization with treadmill and then 8 weeks high intensity interval training). Then, the expression levels of eukaryotic initiator factor 2-alpha (eIF-2-α) and tumor necrosis factor alpha (TNF-α) in the liver tissue of all rats were measured by western blot method.

Blood glucose level and expression of both eIF2-α and TNF-α were significantly higher in the "diabetic control" than the "healthy control" (P≤0.05). The "diabetic exercise" group showed significantly lower glucose level than the the "diabetic control" group (P≤0.05). However, neither eIF-2-α nor TNF-α showed significant change in "diabetic exercise" compared to the "diabetic control" group.

Intense intermittent exercise with the parameters used in this research could not change two stress markers of liver ER in type 2 diabetic rats.