Heart failure: a model of cardiac and skeletal muscle energetic failure

Area of Science:

• Cardiology
• Molecular Biology
• Exercise Physiology

Background:

• Chronic heart failure (CHF) is a growing epidemic characterized by widespread energetic deficits.
• Both cardiac and skeletal muscles exhibit impaired energy production and utilization in CHF.
• Distinct myopathic phenotypes exist between cardiac and skeletal muscles in CHF.

Purpose of the Study:

• To review recent advancements in cardiac and skeletal muscle energy metabolism research in CHF.
• To propose energetic failure as a unifying mechanism for contractile dysfunction in CHF.
• To elucidate the role of gene regulation in muscle abnormalities.

Main Methods:

• Literature review of recent studies on cardiac and skeletal muscle energetics in CHF.
• Comparative analysis of myopathic phenotypes in cardiomyocytes and skeletal muscle fibers.
• Examination of gene regulatory changes impacting muscle energy metabolism.

Main Results:

• Cardiomyocytes show reduced mitochondrial oxidative capacity and altered substrate utilization.
• Skeletal muscle myopathy in CHF presents with less clear mitochondrial failure but altered microvascular function and energy distribution.
• Gene expression changes underlie the observed metabolic and functional abnormalities in both muscle types.

Conclusions:

• Energetic failure is a critical unifying mechanism driving contractile dysfunction in CHF.
• Impaired energy metabolism in skeletal muscle contributes to exertional fatigue and reduced quality of life.
• Understanding these energetic deficits offers potential therapeutic targets for CHF management.