APOE and atherosclerosis: At an early/intermediate stage of atherosclerosis (15-week-old mice), the level of α-SMA (VSMC lineage marker) was similar in both genotypes, while sm-MHC and smoothelin (all terminal differentiation contractile markers) were significantly decreased in ApoE−/−AOC3−/− mice compared to ApoE−/− mice by western blot (Figure 3A).