This study aimed at discussing the effect of aerobic exercise on expression of insulin-like growth factor 1 (IGF-1) and its receptor Insulin like growth factor-1 receptor (IGF-1R) in skeletal muscle of obese mice, downstream signaling pathway of PI3K/Akt, skeletal muscle inflammation and atrophy. 35 healthy male C57BL/6 mice were randomly divided into normal control group (C, 10 mice) and high-fat diet group (25 mice). After 8 weeks, 20 obese mice were randomly divided into obesity control group (OS) and obesity exercise group (OE), 10 mice in each group. The OE group underwent treadmill aerobic exercise for 8 weeks. After training, the protein expression of IGF-1/IGF-1R, pPI3K/PI3K, pAkt/Akt, TNF-α, IL-1β, IL-10, Atrogin-1 and MuRF1 in skeletal muscle were measured by Western blotting. The cross-sectional area of skeletal muscle was observed and calculated by HE staining. The results showed that compared with C group, body weight in OS group was significantly increased, skeletal muscle IGF-1/IGF-1R, pPI3K/PI3K, pAkt/Akt and IL-10 protein expression were significantly downregulated, while TNF-α, IL-1β, Atrogin-1 and MuRF1 protein expression were significantly upregulated, the skeletal muscle cross-sectional area and gastrocnemius/body weight ratio were significantly decreased. Compared with OS group, body weight in OE group was significantly decreased, skeletal muscle IGF-1/IGF-1R, pPI3K/PI3K, pAkt/Akt and IL-10 protein expression were significantly upregulated, while TNF-α, IL-1β, Atrogin-1 and MuRF1 protein expression were significantly downregulated, the skeletal muscle cross-sectional area and gastrocnemius/body weight ratio were significantly increased. Conclusions are as follows, Aerobic exercise may via upregulate the expression of IGF-1 and its receptor IGF-1R protein in skeletal muscle of obese mice, activates the signaling pathway of PI3K/Akt, and inhibit inflammatory response. It shows that the signaling pathway of IGF-1/PI3K/Akt plays an important role in aerobic exercise inhibits the skeletal muscle inflammation of obese mice and improves skeletal muscle atrophy.

Hao Meili. Aerobic Exercise Activates the Signaling Pathway of IGF-1/PI3K/Akt to Inhibit Skeletal Muscle Inflammation in Obese Mice. International Journal of Frontiers in Medicine (2024), Vol. 6, Issue 5: 121-127. https://doi.org/10.25236/IJFM.2024.060517.

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