APOE and atherosclerosis: As shown in Fig. 1a and b, analysis of H&E- and Oil Red O-stained histological sections of the aortic sinus revealed that atherosclerotic lesions and lipid content were significantly higher in the HFD group (p < 0.05) than in the NOR group, suggesting that the HFD successfully induced atherosclerosis in ApoE (-/-) mice.