GRSF1 Protects Against Heart Failure by Maintaining BCAA Homeostasis.
Summary
GRSF1 is downregulated in failing human and murine hearts; cardiomyocyte-specific loss precipitates dilated cardiomyopathy and heart failure, while overexpression protects against pressure overload. Mechanistically, GRSF1 binds G-tracts within BCKDHB mRNA to stabilize it, preserving BCAA metabolism and mitochondrial function; benefits are partly abrogated by BCKDHB deletion.
Key Findings
- GRSF1 expression is reduced in failing human and mouse hearts.
- Cardiomyocyte-specific GRSF1 deletion causes dilated cardiomyopathy and heart failure with hypertrophy and fibrosis.
- GRSF1 binds G-tracts in BCKDHB mRNA to stabilize it, preserving BCAA metabolism and mitochondrial function; cardioprotection is partly lost with cardiac BCKDHB deletion.
Clinical Implications
GRSF1–BCKDHB modulation could enable metabolic therapies for heart failure independent of hemodynamics; translational biomarkers of BCAA flux may help select responsive patients.
Why It Matters
Identifies a previously unrecognized RNA-binding protein checkpoint linking mRNA stability to cardiac BCAA metabolism and heart failure pathogenesis, revealing a druggable axis (GRSF1–BCKDHB).
Limitations
- Translational applicability to human therapeutic targeting requires validation in large animal models
- Precise safety profile of altering BCAA flux in chronic heart failure remains unknown
Future Directions
Develop small molecules or RNA-based therapeutics to modulate GRSF1–BCKDHB, validate efficacy in large animals, and identify circulating biomarkers of BCAA metabolism for patient stratification.
Study Information
- Study Type
- Basic/Mechanistic research
- Research Domain
- Pathophysiology/Treatment
- Evidence Level
- IV - Preclinical mechanistic evidence in human tissues and animal models
- Study Design
- OTHER