To examine whether xyloketal B administration can improve endothelial integrity in vivo during atherosclerosis, apoE−/− mice fed with high-fat diet were treated with vehicle or xyloketal B (14 mg/kg/day) or simvastatin (10 mg/kg/day), respectively, for eight weeks, C57BL/6J mice fed with high-fat diet served as control group. This evidence concerns the gene APOE and atherosclerosis.