RNA-binding protein RBM47 enhances ENC1 stability through AU-rich elements to induce oxidative stress in macrophages...

Macrophages play central roles in the initiation and growth of atherosclerosis (AS). This study aimed to investigate the role of ENC1 in macrophage oxidative stress during AS and its mechanism. An animal model of AS was constructed by feeding ApoE KO mice with a high-cholesterol diet, and an in vitro AS model was induced on mouse macrophages RAW 264.7 using oxLDL. Macrophage-specific adeno-associated viruses containing the F4/80 promoter were used to interfere with RBM47 and ENC1 expression in vivo, and lentiviral infection of RAW 264.7 was applied in vitro. RBM47 improved the stability of ENC1 by binding to the AU-rich elements, which curbed NRF2 synthesis and nuclear translocation. Exogenous inhibition of ENC1 or RBM47 suppressed aortic oxidative stress in mice with AS, reduced lipid and cholesterol uptake, and strengthened cellular scavenging activity against oxidative stress in RAW 264.7 cells. The NRF2 inhibitor ML385 reversed the above benefits from the knockdown of ENC1 in RAW 264.7 cells, and combined overexpression of ENC1 reversed these benefits from the knockdown of RBM47 in vitro and in vivo. This study provides new evidence that ENC1 is a contributor to AS progression, and targeting ENC1 in macrophages may serve as a potential therapy.