WTAP Promotes Atherosclerosis by Inducing Macrophage Pyroptosis and M1 Polarization through Upregulating NLRP3.

Abstract

The study was designed to investigate the impact of N6-methyladenosine (m6A) writer Wilms tumor 1-associated protein (WTAP) on the progression of atherosclerosis (AS) and to further elucidate its possible regulatory mechanism. The m6A levels and WTAP expressions were initially assessed through RIP, qRT-PCR, and western blotting. An in vitro model of AS was constructed by ox-LDL treatment in RAW264.7 cells. Next, the impact of WTAP on macrophage pyroptosis and M1 polarization was evaluated. The relationship between WTAP and NLRP3 was then investigated using m6A modification quantification and RIP-qPCR assay. To investigate the effect of WTAP on AS development in vivo, we created an ApoE^-/-mouse model of AS by feeding high-fat diet (HFD). Furthermore, the influence of WTAP on macrophage pyroptosis and M1 polarization through NLRP3 was explored by NLRP3 overexpression AAV injection. Here, we found that WTAP was significantly upregulated in peripheral blood mononuclear cells (PBMCs) from AS patients, accompanied by increased total m6A methylation levels. The silencing of WTAP suppressed macrophage pyroptosis and M1 polarization induced by ox-LDL and also ameliorated aortic root lesion damage in AS mice. Mechanistically, m6A modification mediated by WTAP enhanced NLRP3 mRNA stabilization, thereby upregulating NLRP3 expression. Overexpression of NLRP3 was found to enhance macrophage pyroptosis and M1 polarization, contributing to the progression of AS. In conclusion, our findings suggest that WTAP knockdown mitigated AS progression by modulating NLRP3 in an m6A-dependent manner. Our study proposes that targeting WTAP could be a potential preventive and therapeutic strategy for AS patients.