Cardiac adaptation to endurance exercise training requires suppression of GDF15 via PGC-1α.

Summary

Cardiomyocyte PGC-1α is required for healthy cardiac adaptation to endurance training by suppressing GDF15. Loss of cardiomyocyte PGC-1α converts exercise into a stressor that precipitates heart failure; blocking cardiac Gdf15 restores performance. Human genetic and tissue data support translational relevance.

Key Findings

• Cardiomyocyte-specific PGC-1α deletion prevented exercise-induced benefits and caused heart failure after 6 weeks of training.
• GDF15 was identified as a key mediator; blocking cardiac Gdf15 improved cardiac performance and exercise capacity in PGC-1α–deficient mice.
• In humans, rare PPARGC1A variants were associated with increased heart failure risk; lower cardiomyocyte PPARGC1A expression correlated with higher GDF15 and reduced cardiomyocyte density.

Clinical Implications

While not immediately practice-changing, the work suggests that circulating/ myocardial GDF15 and cardiomyocyte PGC-1α activity could serve as biomarkers to guide training regimens or recovery. It raises caution for intensive exercise in patients with impaired PGC-1α signaling and supports therapeutic exploration of GDF15 modulation.

Limitations

• Primary evidence is preclinical; human data are associative and not interventional.
• Generalizability to diverse exercise modalities, comorbidities, and ages remains to be established.

Future Directions

Prospective human studies to evaluate GDF15/PGC-1α as biomarkers for exercise prescription, and early-phase trials testing safe GDF15 modulation in cardiac conditions characterized by exercise intolerance.