Pomegranate Compound Improves Heart Function in Hard-to-Treat Heart Failure Models

A compound the body produces after eating pomegranates, walnuts and some berries improved heart function by as much as 80% in experimental models of a hard-to-treat type of heart failure, King's College London scientists found. The compound, urolithin A, improved the heart's ability to relax, reduced scarring and limited harmful enlargement in the models.

The findings target heart failure with preserved ejection fraction (HFpEF), in which the heart still pumps normally but becomes too stiff to relax and refill between beats. HFpEF causes about half of all heart failure cases and could affect nearly half a million people in the UK, with symptoms including breathlessness and fatigue. Treatment options remain limited: the condition can stem from aging, high blood pressure or diabetes, and conventional heart failure drugs are less effective since pumping is not the problem.

Interest in urolithin A has grown because it is linked to healthy aging and mitochondrial function, the process by which cells make energy. The researchers found for the first time that urolithin A activates a protein called PKGlα, which helps relax heart muscle, by acting on a specific amino acid within it. In animal models, the compound improved heart function measures by up to 80%, helped heart tissue relax, and reduced fibrosis, the harmful buildup of scar tissue.

The team also tested urolithin A in engineered human heart tissue grown from stem cells and found relaxation improved there too. The compound has already shown a favorable safety profile in human studies, though more research is needed before it becomes a treatment. "While there isn't enough evidence to suggest that people should eat pomegranates to treat heart failure, these findings raise the possibility that dietary approaches ... may help alleviate this condition," said senior author Dr. Joseph Burgoyne.

Professor James Leiper of the British Heart Foundation said HFpEF "makes up roughly half of all heart failure cases in the UK, and can be debilitating," and that the early-stage study suggests urolithin A may help the heart relax and fill with blood between beats.