Longevity & AgingGut Bacterium Worsens Heart Attack Damage by Destroying a Protective Hormone
Restoring blood flow after a heart attack can itself injure heart tissue, a problem called ischemia/reperfusion (I/R) injury. This mouse study points to the gut as a contributor. I/R lowered oxygen and raised lactate in the intestine, which favored growth of Bacteroides acidifaciens. This microbe makes its own dipeptidyl peptidase 4 (BaDPP4), an enzyme that breaks down protective peptides in plasma, including GLP-1, and so worsens cardiac damage. Fecal microbiota transplantation transferred the harmful effect. Daurisoline, a compound that inhibits microbial DPP4, reduced cardiac dysfunction in mice. In patients with acute myocardial infarction, B. acidifaciens abundance and BaDPP4 levels tracked with markers of cardiac damage. The findings outline a gut-heart axis and suggest a possible microbiota-directed cardioprotective strategy, though this remains preclinical and the patient data are correlational.
