Flavonifractor Plautii or Its Metabolite Desaminotyrosine as Prophylactic Agents for Alleviating Myocardial Ischemia/Reperfusion Injury.

Myocardial ischemia/reperfusion (I/R) injury is a major contributor to myocardial damage, leading to adverse cardiac remodeling and dysfunction. Recent studies have highlighted the potential of gut microbiota-derived metabolites in modulating cardiac outcomes. Here, the cardioprotective effects of a commensal bacterium Flavonifractor plautii (F. plautii) and its metabolite desaminotyrosine (DAT) against myocardial I/R injury are investigated. We showed that prophylactic gavage of F. plautii attenuates myocardial I/R injury as evidenced by improved cardiac function and reduced cardiac injury. We also found that its metabolite DAT recapitulates these cardioprotective effects against myocardial I/R injury. Transcriptomic analysis has revealed that DAT preserves cardiac tissue and attenuates immune responses against myocardial I/R injury. Mechanistically, DAT promotes cardiomyocyte survival through the modulation of the nicotinamide adenine dinucleotide phosphate (NADP(+)/NADPH) ratio. Further, DAT suppressed macrophage proinflammatory activities and cardiac inflammation via the reduction in interleukin-6 (IL-6) production. Taken together, our findings indicate that F. plautii and its metabolite DAT exert pleiotropic cardioprotective effects against myocardial I/R injury, suggesting them as potential prophylactic therapeutic options for alleviating myocardial I/R injury.