Effect of aerobic training on heat shock protein 27 and brain-derived neurotrophic factor in hippocampus and prefrontal cortex of type II diabetic rats

Background: According to the experimental studies, the levels of heat shock protein 27 (HSP27) and brain-derived neurotrophic factor (BDNF) are decreased in diabetes which is associated with impaired cognitive function in the brain. Therefore, the increased expression of these two proteins in some brain regions associated with learning and memory can be one of the positive effects of aerobic training on cognition improvement at diabetes. The aim of the present study was to evaluate the effects of aerobic treadmill exercise training (ATET) on HSP27 and BDNF proteins in the prefrontal cortex and hippocampus of streptozotocin (STZ)-induced diabetes in rats.

Methods: Twenty healthy adult male Wistar rats approximately 3-month old, weighing 250 ± 25gr were used in this study. Experimental diabetes was induced by a high-fat diet (HFD) for 4 weeks and a low dose of STZ (35 mg/kg, intraperitoneally). Then diabetic animals were divided into two groups (n=10 per each group): control group (C) and aerobic training group (E). The exercise program was treadmill running at 13 m/min, 25 min/day, for 5 days/week at 0˚ slope for the first week, with a gradual increase to 27 m/min for 60 min/day in week 8. Un-paired t-test was used to compare two groups with the considered significant at p<0.05.

Results: The results showed that ATET significantly increased protein expression of HSP27 and BDNF in the hippocampus and prefrontal cortex as compared to C group.

Conclusion: Our findings showed that aerobic treadmill exercise program can increase the protein expression of HSP27 and BDNF associated with cognition and synaptic plas­ticity and thus counteract the neurodegenerative diseases of the nervous system.