Gut Microbiota-derived Acetate Safeguards the Colonic Epithelial Acetyl-CoA Reserve to Avert Colonic Senescence

Aging is a major driver of tissue senescence, but little is known about the development of age-unrelated tissue senescence. Here we show that nucleocytosolic acetyl-CoA deficiency in colon epithelial cells, caused by Acly ablation and bacterial depletion, triggers age-independent, p53-dependent colonic senescence leading to severe systemic inflammation. Acetate supplementation, acetate-producing bacterial transplantation, targeted depletion of senescent cells or treatment with lysine deacetylase inhibitors blocks colonic senescence and inflammatory injury. Spontaneous colonic senescence develops following simultaneous deletion of epithelial Acly and Acss2, confirming that microbe-derived acetate maintains the epithelial acetyl-CoA pool via ACSS2 to avert colonic senescence. Mechanistically, acetyl-CoA deficiency deprives a cohort of mitochondrial and nuclear proteins of acetylation, leading to increased oxidative stress and DNA repair stress that trigger cellular senescence. Among these proteins, ATP5F1A-K161 acetylation and H4-K5/8 acetylation are required to protect colonic epithelial cells from developing senescence. These observations unveil a previously unknown mechanism that governs colonic senescence.