Mice and rats fed a compound found in legumes, grains and aged cheese lived longer with improved cardiovascular health – and should be tested in clinical trials in humans, according to the researchers.
Frank Madeo from the University of Graz in Austria and colleagues added spermidine – a naturally occurring organic compound that’s been shown to increase the lifespan of worms and fruit flies – to rodents’ drinking water.
They found those which drank the spermidine-spiked water – even if that access didn’t begin until the mice and rats were “middle-aged” – lived longer with a healthier heart and lower blood pressure.
The results were published in Nature Medicine.
So how does spermidine work?
It’s thought to increase an organism’s lifespan by activating a special cellular process known as autophagy in cardiac cells.
The process, which won its discoverer this year’s Nobel prize for medicine, helps cells recycle their components.
To test this theory, Madeo and his crew also tested spermidine in mice with genetic issues with autophagy. Interestingly, among this group, the spermidine had no effect on heart function.
Then, to see how spermidine intake might correlate with human heart health, the researchers quizzed around 800 people in the town of Bruneck, Italy on their diet (from which they calculated spermidine intake) and their cardiovascular health.
Those who reported eating more spermidine also showed a lower risk of heart failure and other cardiovascular disease.
The researchers acknowledge that questionnaires aren’t an ideal source for statistics – their sample came from one town – and that at this point, they can only surmise whether the life-prolonging effect of spermidine is due to its effect on cardiovascular health.
“In the ageing population, the incidence and prevalence of heart failure are increasing in association with co-morbidities such as obesity, diabetes and renal abnormalities,” the researchers report.
“Our study paves the way for prospective clinical trials to evaluate the potential cardiovascular- and other health-promoting effects of spermidine-enriched diets.”