Urolithin Metabolism and Health Implications

Urolithins are a class of microbial metabolites generated from dietary ellagitannins and ellagic acid through sequential transformations by the human gut microbiota. Following ingestion of ellagitannin-rich foods such as pomegranates, berries and nuts, ellagitannins are hydrolysed to ellagic acid, which in turn is converted by intestinal bacteria into a series of urolithin intermediates and ultimately into urolithin A, B and isourolithin A. These compounds undergo phase II conjugation in the intestinal epithelium and liver, circulate systemically, and accumulate in target tissues at physiologically relevant concentrations. Emerging research has linked urolithins to modulation of autophagy, mitochondrial function, inflammatory signalling and energy metabolism, thus offering protective effects across a range of disorders, including cancer, cardiometabolic disease, neurodegeneration and ageing. Inter-individual variability in the gut microbial community gives rise to distinct urolithin metabotypes, influencing both the spectrum of urolithins produced and the magnitude of health benefits. Translational studies underscore the potential of urolithin-based interventions—whether through diet, probiotics or direct supplementation—to harness microbial metabolism for human health. Ongoing investigations aim to refine our understanding of urolithin pharmacokinetics, identify the key bacterial species responsible for conversion, and define optimal strategies for personalised nutrition and therapeutic development.

Research from Nature Portfolio

No recent Nature Portfolio content available.

Urolithin Metabolism and Health Implications publication trend

The graph below shows the total number of articles in urolithin metabolism and health implications across all publications each year (not limited to Nature Index journals).

Technical terms

Ellagitannins: Polyphenolic compounds in certain fruits and nuts that release ellagic acid upon hydrolysis.

Urolithins: Gut microbial metabolites derived from ellagic acid, existing as multiple hydroxy-substituted derivatives and their conjugates.

Metabotype: Classification of individuals based on the capacity of their gut microbiota to produce specific urolithins.

Autophagy: Cellular process of lysosomal degradation of damaged organelles and proteins, vital for maintaining mitochondrial function.

Phase II conjugation: Host metabolic reactions (glucuronidation, sulfation) that increase solubility and systemic distribution of microbial metabolites.

References

1. Urolithin A Hijacks ERK1/2‐ULK1 Cascade to Improve CD8+ T Cell Fitness for Antitumor Immunity. Advanced Science (2024).
2. Urolithin A protects severe acute pancreatitis‐associated acute cardiac injury by regulating mitochondrial fatty acid oxidative metabolism in cardiomyocytes. MedComm (2023).
3. Urolithins: a Comprehensive Update on their Metabolism, Bioactivity, and Associated Gut Microbiota. Molecular Nutrition & Food Research (2022).