For the June edition of Journal Club, Dr. Oliver Medvedik and guests took a look at the recent human trial of urolithin A, a metabolite produced by microflora and an active ingredient in pomegranates that is linked to increased levels of mitophagy in aged animals.
Urolithin A is a byproduct created when bacteria in the gut break down ellagitannins, which are certain kinds of polyphenols found in fruits such as pomegranates, strawberries, walnuts, and raspberries. The substance does not appear naturally in its end form, so we normally rely on the beneficial bacteria in the microbiome, our internal ecology of gut bacteria, to convert the polyphenols into urolithin A.
Researchers synthesized the urolithin A in the lab and directly gave it to patients, thus bypassing the need to have the particular bacteria that creates it, which some people have and some do not. This reliance on bacteria to create it also explains why some people benefit from eating foods rich in ellagitannins or taking pomegranate supplements and why others gain no benefits. Directly creating urolithin A allows researchers to remove this need to have the bacteria process the urolithin A, which could potentially mean that everyone could enjoy the benefits.
The human trial produced some interesting and promising results, and it seems that this compound may actually delay the mitochondrial dysfunction seen during aging. There are lots of supplements on the market, and it is likely that most of them are absolute junk and snake oil, but there could also be some out there which are useful; urolithin A is looking like it may be.
Andreux, P. A., Blanco-Bose, W., Ryu, D., Burdet, F., Ibberson, M., Aebischer, P., … & Rinsch, C. (2019). The mitophagy activator urolithin A is safe and induces a molecular signature of improved mitochondrial and cellular health in humans. Nature Metabolism, 1(6), 595.