Inhibition of ACSS2-mediated crotonylation alleviates kidney fibrosis via IL- 1ß-dependent macrophage activation and tubular cell senescence
Chronic kidney disease (CKD) is characterized by sustained inflammation and progressive fibrosis, however therapies to slow CKD progression are limited. Histone lysine crotonylation (Kcr) as a novel post-translational modification is widespread as acetylation (Kac), but its roles in CKD are largely unknown. In the study, we firstly reported that the nuclear histone Kcr in tubular epithelial cells was significantly elevated in fibrotic kidney of patients and mice, which was positively correlated with the progression of disease. Interestingly, abnormal increase of histone 3 lysine 9 crotonylation (H3K9cr) in kidneys of unilateral ureteric obstruction (UUO) and folic acid nephropathy (FAN) was completely different to the stable expression of H3K9ac, indicating that H3K9cr may exert extraordinary functions in kidney fibrosis. By screening these crotonylated/acetylated factors, crotonyl-CoA-producing enzyme ACSS2 (acyl-CoA synthetase short chain family member 2) remarkably promoted H3K9cr without influencing H3K9ac to trigger proinflammatory cytokine IL-1ß transcription. Furthermore, genetic and pharmacologic inhibition of ACSS2 both attenuated kidney injury and fibrosis, as well as suppressed H3K9cr-mediated IL-1ß expression, which thus to alleviate IL-1ß-dependent macrophage activation and tubular cell senescence. Collectively, our finding uncovers that H3K9cr plays a critical, previously unrecognized role in kidney fibrosis, where ACSS2 represents an attractive target for strategies that aim to slow fibrotic kidney disease progression Overall design: To understand the functions of ACSS2 in kidney fibrosis, we established ACSS2 konckout mouse and perform rnaseq analysis