GFPT2 promotes macrophage dysfunction in atherosclerosis via ACADL glycosylation-dependent suppression of ACADL and Arg1

Atherosclerosis (AS) is a chronic inflammatory disease characterized by lipid-laden macrophage foam cell formation and defective efferocytosis. This study aims to investigate the impact of GFPT2 on macrophage function in AS and its underlying mechanisms. We established an AS model using high-fat diet-fed ApoE−/− mice and ox-LDL-treated RAW264.7 and bone marrow-derived macrophages. H&E staining was conducted to examine histopathological changes in the abdominal aorta. Foam cell formation was evaluated by Oil-red-O staining and Dil-ox-LDL uptake, while efferocytosis was measured using apoptotic thymocyte clearance assays. Protein glycosylation was analyzed via PNGase F digestion and site-directed mutagenesis. GFPT2 knockdown and overexpression were performed to assess its functional role. GFPT2 was upregulated in abdominal aortic tissues and peritoneal macrophages from AS mice, as well as ox-LDL-treated macrophages. In vitro, GFPT2 knockdown reduced foam cell formation, enhanced macrophage efferocytosis, suppressed pro-inflammatory responses, and attenuated mitochondrial ROS production. Notably, GFPT2 downregulated ACADL and Arg1 expression by promoting ACADL N-glycosylation. Moreover, GFPT2 disrupted macrophage function in AS models through regulating Arg1. ACADL knockdown suppressed GFPT2 knockdown-improved macrophage function in AS models. Furthermore, GFPT2 knockdown attenuated the ox-LDL-induced activation of NF-κB and STAT2 and suppression of PPARγ expression. In vivo, GFPT2 knockdown improved serum lipid profile, ameliorated plaque burden, enhanced macrophage efferocytosis, and reduced systemic inflammation in AS mice. Our findings revealed a novel GFPT2-ACADL-Arg1 regulatory axis in AS, where GFPT2 suppressed Arg1 expression via promoting ACADL glycosylation, thereby promoting foam cell formation, impairing efferocytosis, and exacerbating inflammation. Moreover, GFPT2 regulated key transcriptional regulators (NF‑κB, STAT2, PPARγ). These results identified GFPT2 as a pivotal regulator of macrophage homeostasis in AS.