Effects of resistance exercise on antioxidant enzyme activities and apoptosis-related protein expression of hippocampus in OLETF rats

Abstract

BACKGROUND:

Studies on antioxidant enzyme activity and apoptosis related protein expression associated with diabetes are mainly limited to aerobic exercise. Since the effectiveness and efficiency of the resistance to diabetes has recently emerged, it is necessary to investigate the effects of regular resistance exercise on these factors.

OBJECTIVE:

The purpose of this study was to investigate the effects of resistance exercise on antioxidant enzymes activities and apoptosis related protein expression in hippocampus of diabetic rats.

METHODS:

Twenty-one male rats were divided into 3 groups: LETO (control group), OLETF (diabetes group) and OLETF $+$ EX (OLETF with resistance exercise group). Resistance exercise consisted of ladder climbing every 5 days for 30 minutes for 8 weeks. The exercise group was trained to climb a 180-cm vertical ladder with weights secured to their tails. Antioxidant enzyme activities, apoptosis related protein expression, and HOMA-IR level were measured.

RESULTS:

The lipid peroxide and superoxide dismutase (SOD) activity were significantly increased in OLETF $+$ EX compared to OLETF ( $p<$ 0.001). Glutathione peroxidase (GPx) activity was significantly lower in OLETF $+$ EX than OLETF ( $p<$ 0.001). Caspase-3 expression of hippocampus was significantly decreased in OLETF $+$ EX compared to OLETF ( $p<$ 0.05). Bax protein expression was significantly lower in OLETF $+$ EX than OLETF ( $p<$ 0.05) whereas Bcl-2 expression was significantly higher in OLETF $+$ EX than OLETF ( $p<$ 0.05). HOMA-IR level was significantly decreased in OLETF $+$ EX compared to OLETF ( $p<$ 0.05).

CONCLUSIONS:

Regular resistance exercise intervention can decrease oxidative stress by enhancing antioxidant enzyme activity and this may lead to attenuate apoptosis related protein such as caspase-3, bax and bcl-2 expression in hippocampus of diabetic population.