Myostatin from the heart: local and systemic actions in cardiac failure and muscle wasting

Area of Science:

• Cardiovascular Medicine
• Skeletal Muscle Physiology
• Molecular Biology

Background:

• Heart failure frequently leads to skeletal muscle wasting and cardiac cachexia, significantly worsening patient prognosis.
• Myostatin, a transforming growth factor-β (TGF-β) cytokine, is a potent inhibitor of skeletal muscle growth and a key mediator of muscle atrophy in heart failure models.
• Elevated serum myostatin levels are observed in heart failure patients, implicating it in the pathophysiology of the disease.

Purpose of the Study:

• To investigate the role of cardiac-derived myostatin in mediating skeletal muscle atrophy and cardiac dysfunction in heart failure.
• To explore the therapeutic potential of myostatin inhibition for combating cardiac cachexia.

Main Methods:

• Utilized mouse models of heart failure with genetic manipulation of myostatin expression in the heart (elimination and overexpression).
• Assessed skeletal muscle mass, cardiomyocyte growth, cardiac fibrosis, and ventricular function.
• Measured circulating myostatin levels in heart failure patients and animal models.

Main Results:

• Genetic elimination of cardiac myostatin attenuated skeletal muscle atrophy in mice with heart failure.
• Transgenic overexpression of cardiac myostatin induced muscle wasting and cardiac abnormalities.
• Cardiac myostatin production was found to negatively impact cardiomyocyte growth, promote cardiac fibrosis, and alter ventricular function.
• Heart failure patients exhibited increased serum myostatin levels.

Conclusions:

• Cardiac myostatin plays a critical endocrine role in mediating skeletal muscle wasting associated with heart failure.
• Inhibition of myostatin presents a promising therapeutic strategy for treating cardiac cachexia and improving skeletal muscle mass in heart failure patients.