Urolithin B is a metabolite of the polyphenolic antioxidant ellagic acid that has diverse biological activities.1,2,3,4 It is formed from ellagic acid via several intermediates by gut microbiota.1 Urolithin B reduces the levels of advanced glycation end products (AGEs) in a cell-free assay in a concentration-dependent manner.2 It inhibits aromatase activity in human placental microsomes and aromatase-sensitive MCF-7 (MCF-7aro) human breast cancer cells when used at concentrations of 47 and 4.7 ?M, respectively.3 Urolithin B (1.18-4.7 nM) inhibits testosterone-induced proliferation of MCF-7aro cells. It also inhibits LPS-induced increases in inducible nitric oxide synthase (iNOS), TNF-α, IL-6, IL-1β, and COX-2, as well as increases levels of IL-10, in BV-2 microglia when used at concentrations of 50 and 100 ?M.4
1.Tomás-Barberán, F.A., González-Sarrías, A., García-Villalba, R., et al.Urolithins, the rescue of "old" metabolites to understand a "new" concept: Metabotypes as a nexus among phenolic metabolism, microbiota dysbiosis, and host health statusMol. Nutr. Food Res.61(1)(2017) 2.Liu, W., Ma, H., Frost, L., et al.Pomegranate phenolics inhibit formation of advanced glycation endproducts by scavenging reactive carbonyl speciesFood Funct.5(11)2996-3004(2014) 3.Adams, L.S., Zhang, Y., Seeram, N.P., et al.Pomegranate ellagitannin-derived compounds exhibit antiproliferative and antiaromatase activity in breast cancer cells in vitroCancer Prev. Res. (Phila.)3(1)108-113(2010) 4.Lee, G., Park, J.-S., Lee, E.-J., et al.Anti-inflammatory and antioxidant mechanisms of urolithin B in activated microgliaPhytomedicine5550-57(2019)