Combined caloric restriction and exercise provides the best benefit in obese brain

Abstract

Background Lifestyle modification, including dietary intervention or exercise training, has beneficial effects on the improvement of metabolic and brain function in cases of metabolic syndrome, diabetes and Alzheimer’s disease. However, the comparative effects of calorie restriction, exercise training, and a combination of calorie restriction and exercise training on brain and cognitive function in the obese condition have not been thoroughly investigated. Our hypothesis is that both calorie restriction and exercise training improve brain and cognitive function in an obese condition, but a combination of these two therapies has a greater efficacy in the restoration of brain functions and cognition than either single therapy. Method Twenty‐five female rats were fed with either a normal diet (ND; n=5) or a high‐fat diet (HFD; n=20) for 27 weeks. At week 20, the ND‐fed rats were assigned to a sedentary lifestyle (NDS; n=5), and HFD‐fed rats were assigned to either a sedentary lifestyle (HFS; n=5), calorie restriction (HFCR; n=5), exercise (HFEX; n=5) or a combination of calorie restriction and exercise (HFCB; n=5) for 7 weeks. After that, metabolic parameters, brain parameters and cognition were determined. Result HFD‐fed rats developed insulin resistance and cognitive decline via increased oxidative stress, inflammation, apoptosis, and synaptic dysfunction in the hippocampus. Calorie restriction decreased metabolic disturbance, decreased inflammation and oxidative stress in the hippocampus, but failed to improve cognition in HFD‐fed rats. Exercise attenuated metabolic disorders, oxidative stress, inflammation, apoptosis, and synaptic dysfunction, resulting in improved cognition in HFD‐fed rats, while the combined therapy had the greatest beneficial effect on this improvement (p<0.05, Figure 1). Conclusion A combination of calorie restriction and exercise may be the best therapeutic approach for the restoration of brain and cognitive function in the obese condition.