Obesity causes insulin resistance and hyperinsulinemia which causes skeletal muscle dysfunction resulting in a decrease in contraction force and a reduced capacity to avoid fatigue, which overall, causes an increase in oxidative stress. K_ATP channel openers such as diazoxide and the implementation of exercise protocols have been reported to be actively involved in protecting skeletal muscle against metabolic stress; however, the effects of diazoxide and exercise on muscle contraction and oxidative stress during obesity have not been explored. This study aimed to determine the effect of diazoxide in the contraction of skeletal muscle of obese male Wistar rats (35 mg/kg), and with an exercise protocol (five weeks) and the combination from both. Results showed that the treatment with diazoxide and exercise improved muscular contraction, showing an increase in maximum tension and total tension due to decreased ROS and lipid peroxidation levels and improved glutathione redox state. Therefore, these results suggest that diazoxide and exercise improve muscle function during obesity, possibly through its effects as K_ATP channel openers.

Obesity is a chronic disease that impairs skeletal muscle function, affects the ability to contract, and promotes the development of fatigue. For this reason, the study of treatments that seek to reduce the harmful effects of obesity on muscle tissue has been deepened. Diazoxide treatment and various exercise protocols have been proposed to protect skeletal muscle against oxidative stress and its effects. However, the intensity and duration of exercise combined with diazoxide that would obtain the best results for improving skeletal muscle function in obese rats is unknown. To this end, this study evaluated the effects of three different exercise intensities combined with diazoxide on contraction capacity, resistance to fatigue, markers of oxidative stress, lipid peroxidation, ROS, and glutathione redox status of skeletal muscle. The results showed that treatments with diazoxide and exercise at different intensities improved muscle contraction capacity by reducing oxidative stress during obesity, with the best results being obtained with low-intensity exercise in combination with diazoxide. Therefore, these results suggest that diazoxide and low-intensity exercise improve muscle function during obesity by decreasing oxidative stress with the same efficiency as a moderate-intensity exercise protocol.

Diabetes mellitus is a chronic degenerative disease characterized by hyperglycemia and oxidative stress. Iron catalyzes free radical overproduction. High iron concentrations have previously been reported to promote an increase in oxidative stress; however, the effect of iron restriction in diabetes has not yet been explored, so we tested to see if iron restriction in diabetic rats reduces oxidative damage and improved muscle function. Wistar rats were assigned to 4 groups: Control; Diabetic; Diabetic rats with a high iron diet, and Diabetic with dietary iron restriction. After 8 weeks the rats were sacrificed, the muscles were extracted to prepare homogenates, and serum was obtained for biochemical measurements. Low iron diabetic rats showed an increase in the development of muscle strength in both muscles. Dietary iron restriction decreased triglyceride concentrations compared to the untreated diabetic rats and the levels of extremely low-density lipoproteins. Aggravation of lipid peroxidation was observed in the diabetic group with a high iron diet, while these levels remained low with iron restriction. Iron restriction improved muscle strength development and reduced fatigue times; this was related to better lipid profile control and decreased oxidant stress markers.

An excess of adipose tissue characterizes obesity; it is associated with complications such as diabetes and cardiovascular diseases due to an alteration in the lipid profile; this condition affects all tissues; even skeletal muscle is the most affected, causing its malfunction and bringing more significant consequences. Exercise has been described as one of the best treatments to combat obesity. At the same time, E. carlinae is a plant proven to have lipid-lowering and hypoglycemic effects, improving the function of various organs. However, its described effect has not been proven in skeletal muscle during obesity. Wistar male rats were separated into 8 groups, 4 healthy and 4 obese, treated with exercise and E. carlinae extract; after 8 weeks, they were sacrificed, muscles were extracted to measure contraction force, and blood was extracted to perform biochemical tests. Both exercise and E. carlinae extract effectively lowered glucose, improved lipid profile, reduced visceral fat, and improved muscle function during obesity. Exercise and E. carlinae extract improved muscle function during obesity, concerning better utilization and lower absorption of lipids.