ACSS2-Mediated Lysine Crotonylation Attenuates Senescence and Enhances the Therapeutic Efficacy of Adipose-derived Stem Cells in Inflammatory Bowel Disease [ChIP-Seq]
Background Inflammatory bowel disease (IBD) remains a significant clinical challenge with limited curative options. Adipose-derived mesenchymal stem cells (ADSCs) hold therapeutic promise, but their anti-inflammatory efficacy is often compromised by cellular senescence. This study investigates the role of lysine crotonylation (Kcr) in ADSCs senescence and explores its therapeutic potential. Methods We analyzed Pan-Kcr levels in senescent ADSCs and evaluated the effects of sodium crotonate (NaCr), a crotonyl-CoA precursor, on senescence, proliferation, and anti-inflammatory function. A murine colitis model was used to assess therapeutic efficacy. Molecular mechanisms focusing on ACSS2-mediated Kcr regulation and H3K9 crotonylation (H3K9cr) at the ACSS2 promoter. Results Senescent ADSCs exhibited a marked decline in Pan-Kcr levels. NaCr treatment ameliorated senescence, enhanced proliferation, and improved anti-inflammatory capacity. ACSS2, a key regulator of Kcr, was downregulated in senescent ADSCs. Moreover, the anti-senescence effect of NaCr depended on ACSS2-mediated crotonylation. NaCr promoted H3K9cr modification at the ACSS2 promoter, forming a positive feedback loop that elevated Kcr levels. Mechanistically, ACSS2-mediated Kcr suppressed the NF-?B pathway to delay ADSCs senescence. Conclusion Our findings reveal an epigenetic pathway (ACSS2-Kcr-H3K9cr) regulating ADSCs senescence and propose Kcr modulation as a novel strategy to enhance ADSCs-based therapy for IBD. Overall design: ChIP-seq of H3K9cr in ADSCs at  passage 3 and passage 7