Rhodiola intervention improves mitochondrial autophagy and fusion-division in skeletal muscle cells of mice with high intensity exercise / 中国组织工程研究

ABSTRACT

BACKGROUND: Excessive exercises cause a large accumulation of oxidative active substances in the body to damage skeletal muscle cells. Mitochondria play a key role in energy metabolism during exercise. Studies have shown that Rhodiola can reduce the level of lipid peroxidation in muscle tissue and protect damaged endothelial cells. OBJECTIVE: To explore the mechanism underlying Rhodiola improving skeletal muscle function of mice with high intensity exercise by regulating mitochondrial function. METHODS: The study protocol was approved by the Ethics Committee of Xi’an Shiyou University in China. Forty BALB/c mice were divided into blank control group, exercise group, Rhodiola control group and Rhodiola intervention group. Mice in the blank control had no exercise and intervention. Mice in exercise group were given intragastric administration of normal saline followed by high intensity exercise. Mice in Rhodiola intervention group and Rhodiola control group were given intragastric administration of the mixture of Rhodiola and normal saline, followed by exercise or not. The interventions were performed once a day for 28 consecutive days. Body mass, forearm grip strength and exhaustion time were observed. Western blot assay was used to detect expression of manganese superoxide dismutase protein, p53 protein, mitochondrial origin and autophagy-associated protein in the skeletal muscle. RT-qPCR was used to detect skeletal muscle Mfn-1, Mfn-2, Opa-1, Drp-1, and fis-1 mRNA expression. RESULTS AND CONCLUSION: (1) From the 2nd week, the grip strength of forelimbs in the exercise group was significantly lower than that in the other three groups (P 0.05). (2) At the 3rd and 4th weeks, the exhaustion time of weight-bearing swimming training was significantly shorter in the exercise group than the Rhodiola intervention group (P 0.05). Compared with the blank control group, the Rhodiola exercise intervention group also showed a downward trend in the expression of fusion gene and an upward trend in the expression of Drp-1 mRNA, but there was no significant difference between the two groups (P > 0.05). To conclude, Rhodiola can significantly improve the exercise endurance of mice with high intensity exercise, which may be related to the improvement of skeletal muscle mitochondrial autophagy, origin and fusion-division.