Urolithins–Gut Microbial Metabolites with Potential Health Benefits

Abstract

Urolithins are bioactive metabolites derived from the gut microbial transformation of ellagitannins found in various foods like pomegranates, berries, and nuts. These metabolites, primarily urolithin A and urolithin B, exhibit diverse biological activities, including anti-inflammatory, antioxidant, anticancer, neuroprotective, antiatherogenic, antidiabetic, and anti-obesity effects. Their mechanisms of action involve modulating various signaling pathways, reducing oxidative stress, and promoting beneficial gut microbiota. Urolithins have been shown to protect cells from oxidative stress, reduce inflammation, and inhibit tumor growth. They also have neuroprotective effects, potentially mitigating neurodegenerative diseases like Alzheimer's and Parkinson's. Additionally, urolithins may contribute to cardiovascular health by reducing cholesterol levels and improving endothelial function. However, the bioavailability and production of urolithins can vary significantly among individuals due to differences in gut microbiota composition. To enhance their therapeutic potential, researchers are investigating strategies to improve bioavailability and optimize production. While preclinical studies have demonstrated the promising effects of urolithins, further clinical research is necessary to fully understand their efficacy and safety in humans. By addressing the challenges associated with bioavailability and individual variability, urolithins may offer a novel therapeutic approach for a variety of diseases. This review article aims to synthesize recent literature on urolithins, with a focus on their potential health benefits, bioavailability, and applications in disease prevention and treatment.