High-Intensity Aerobic Exercise Prevents Angiotensin II-Induced Muscle Atrophy

Area of Science:

• Physiology
• Molecular Biology
• Exercise Science

Background:

• Angiotensin II (Ang II) is a key factor in hypertension and is increasingly linked to skeletal muscle damage and atrophy.
• The exact molecular mechanisms of Ang II-induced muscle atrophy and the potential benefits of exercise remain under investigation.

Purpose of the Study:

• To investigate the impact of Ang II on skeletal muscle structure and atrophy-related molecular markers.
• To determine if aerobic exercise can protect against Ang II-induced muscle alterations in an animal model.

Main Methods:

• Forty-eight 6-week-old mice were divided into control, Ang II, Ang II + low-intensity exercise (LIE), and Ang II + high-intensity exercise (HIE) groups.
• Ang II was administered daily for 4 weeks. Exercise groups received daily Ang II injections alongside their respective exercise protocols.

Main Results:

• High-intensity exercise significantly reduced inflammatory factor expression compared to the Ang II group.
• Muscle protein synthesis markers (IGF-1, AKT, mTOR, S6K1) were significantly higher in exercise groups versus the Ang II group.
• Autophagy-related factor expression was notably elevated in the Ang II+HIE group compared to the Ang II group.

Conclusions:

• Aerobic exercise, particularly high-intensity, effectively attenuates Ang II-induced skeletal muscle atrophy.
• Exercise interventions may counteract Ang II's detrimental effects on muscle by modulating inflammation, protein synthesis, and autophagy pathways.