Researchers at King’s College London have discovered that urolithin A, a natural metabolite produced when gut bacteria break down compounds found in pomegranates, walnuts, and berries, improved heart function by up to 80 percent in animal models. Published in Science Advances and funded by the British Heart Foundation, the study shows this compound activates a key protein to ease heart stiffness.
In Plain English: The Clinical Takeaway
- The Core Mechanism: Urolithin A stimulates a protein known as PKG1α, which plays a role in heart muscle relaxation and blood vessel regulation.
- The Target Condition: The research focuses on heart failure with preserved ejection fraction (HFpEF), a condition where the heart continues to pump properly but struggles to relax between each beat.
- The Clinical Reality: While lab tests on animal models and engineered human heart tissue showed reduced scarring and improved relaxation, human clinical trials are still required to establish whether urolithin A can safely improve heart relaxation and symptoms in people.
Cellular Pathways and the Mechanism of Action in Stiff Heart Tissue
Heart failure with preserved ejection fraction (HFpEF) represents a clinical challenge. In this condition, the heart continues to pump properly, but it struggles to relax between each beat. Aging, high blood pressure, diabetes, and obesity can contribute to the changes that make the heart less flexible, leaving physicians with limited therapeutic options.
Investigators at King’s College London analyzed how urolithin A interacts with cardiac tissue at a molecular level. Their tests demonstrated that urolithin A turns on a protein called PKG1α, which is connected to heart muscle relaxation and blood vessel activity. By locking onto a specific amino acid present on the protein, the compound appears to initiate a pathway that renders heart tissue more flexible and responsive. The researchers also found less fibrosis, or excessive scar tissue, in the heart. The treatment also limited the enlargement of individual heart muscle cells.
In animal models, urolithin A improved measures of heart function by as much as 80 percent compared with untreated models. To bridge the gap toward human application, the research team also tested the metabolite on engineered human heart tissue made using human stem cells. The compound improved relaxation in the engineered tissue.
Evaluating Dietary Sources Versus Controlled Clinical Development
While public enthusiasm often surges around foods associated with longevity and health, experts caution that the study does not show that eating pomegranates, walnuts or berries can treat heart failure. Urolithin A is a substance linked to foods including pomegranates, walnuts and some berries.
Joseph Burgoyne, senior author of the study, emphasized the distinction between laboratory findings and dietary prescription. Although current data does not support eating pomegranates as a heart failure treatment, these discoveries indicate that nutritional strategies boosting urolithin A levels could potentially help manage the illness.
To determine if urolithin A can safely enhance heart relaxation and alleviate symptoms for HFpEF patients, formal clinical trials will be necessary.
| Research Parameter | Preclinical Finding | Clinical Status |
|---|---|---|
| Target Condition | HFpEF (Heart Failure with Preserved Ejection Fraction) | Requires Clinical Trials |
| Primary Molecular Target | PKG1α Protein Activation | Identified in Animal Models and Lab-Grown Human Tissue |
| Functional Outcome | Up to 80% improvement in heart function in animal models | Pending Human Efficacy Data |
| Primary Funding Source | British Heart Foundation | Ongoing Academic and Institutional Support |
Contraindications & When to Consult a Doctor
Patients diagnosed with cardiovascular disease, hypertension, or any form of heart failure must consult with their medical team regarding their care. Anyone experiencing worsening cardiac symptoms—such as acute shortness of breath, sudden fatigue, fluid retention, or chest pain—must seek medical evaluation.
Future Clinical Trajectory for Cardiovascular Therapeutics
The identification of urolithin A as an activator of the PKG1α pathway provides a therapeutic target. As populations age and the prevalence of metabolic risk factors climbs, addressing cardiac stiffness remains a primary objective for researchers.
Advancing this candidate toward human therapeutics will require clinical trials to establish safety and actual clinical outcomes. Until those trials publish data, standard management of underlying metabolic conditions remains the cornerstone of patient care.
References
- Su et al., Science Advances, 2026.
