Effects of different types of exercise on skeletal muscle atrophy, antioxidant capacity and growth factors expression following myocardial infarction.
Cai. Mengxin M; Wang. Qing'an Q; Liu. Zhiwei Z; Jia. Dandan D; Feng. Rui R; Tian. Zhenjun Z
Key Findings
- All three exercise modes improved cardiac function and reduced heart scar tissue.
- Exercise increased muscle weight and fiber size while lowering atrophy genes (MURF1, atrogin‑1).
- Natural levels of IGF‑1, MGF, and NRG1 rose in skeletal muscle, correlating with better heart performance.
Practical Outcomes
- For biohackers interested in boosting IGF‑1/MGF pathways, regular resistance training or moderate‑intensity continuous cardio can naturally raise these growth factors and protect muscle mass, especially after stress like a heart injury. High‑intensity interval training may be less safe early on. Incorporating structured exercise may complement peptide use by enhancing the body’s own IGF‑1/MGF signaling and antioxidant capacity.
Summary
In rats that had a heart attack, three kinds of exercise (resistance, steady moderate cardio, and high‑intensity interval cardio) all helped the heart work better and stopped the leg muscles from shrinking. The workouts lowered muscle‑wasting genes, cut oxidative stress, boosted antioxidant defenses, and increased the natural muscle‑building signals IGF‑1, MGF, and related factors. Resistance and moderate cardio were safest and most effective early after a heart attack.
Abstract
Myocardial infarction (MI) is accompanied with skeletal muscle abnormalities. The aims are to explore an optimal exercise mode to improve cardiac function and prevent skeletal muscle atrophy, and detect the possible mechanisms of exercise-induced inhibition of muscle atrophy. Rats were subjected to four weeks of different types of exercise after MI surgery (resistance training, RT; moderated-intensity continuous aerobic exercise, MCE and high-intensity intermittent aerobic exercise, HIA). Cardiac function, histological changes of heart and skeletal muscle, oxidative stress, antioxidant capacity and the expression of muscle atrophy-related factors were detected in skeletal muscle. The three types of exercise improved heart function, reduced cardiac fibrosis and increased muscle weight and cross-section area (CSA) of muscle fibers in different degrees. The survival rates of MI rats intervened by RT and MCE were higher than HIA. Exercise down-regulated the mRNA levels of murf1 and atrogin-1, decreased reactive oxygen species level, increased antioxidant capacity, regulated the expression of insulin-like growth factor 1 (IGF1), mechano growth factor (MGF), Neuregulin1 (NRG1) and Myostatin (MSTN), and activated Akt and Erk1/2 signalings in soleus muscle. Furthermore, CSA of muscle fibers and the expression of IGF1, MGF, NRG1 in skeletal muscle had correlations with cardiac function. RT and MCE are the first two choices for the early exercise rehabilitation following MI. All types of exercise can effectively inhibit skeletal muscle atrophy through increasing the antioxidant capacity, reducing oxidative stress and protein degradation, and regulating the growth factors expression in skeletal muscle.
Study Information
pubmed
2018
2018-10-09T00:00:00.000Z
10.1016/j.lfs.2018.10.015
43
77