APOE and aortic atherosclerosis: This study demonstrated that overexpression of SFRP4 inhibited aortic atherosclerosis in ApoE KO mice, however, no significant difference in plasma TC, TG, LDL-C, and glucose were observed, but only HDL-C was significantly elevated after overexpression of SFRP4, indicating that the practical effects of SFRP4 is partly dependent on increasing HDL-C plasma cholesterol levels [28].