Protective Effect of Angiotensin Converting Enzyme 2 Transfection on Vascular Endothelial Cells / 中国循环杂志

ABSTRACT

Objective: To investigate the inlfuence of angiotensin converting enzyme 2 (ACE2) on lectin-like oxidized low density lipoprotein receptor-1 (LOX-1) protein expression and to explore the protective effect of ACE2 on vascular endothelial cells. Methods: Our work includedin vitro andin vivo studies. For in vitro experiment, the human umbilical vein endothelial cell (HUVEC) were cultured and transfected with replication deficient recombinant adenovirus of ACE2 (Ad-ACE2), and LOX-1 protein expression stimulated by angiotensin 2 was examined by Western blot analysis. Forin vivo study, atherosclerosis plaques were induced in 20 apolipoprotein E-deifcient (ApoE-/-) mice, and then randomly divided them into 2 groups: ACE2 group, the mice received Ad-ACE2 (2.5×109 pfu/ml) injection through caudal vein, EGFP (enhanced green lfuorescent protein) group, the mice received equal replication deifcient recombinant adenovirus of EGFP (Ad-EGFP) injection through caudal vein.n=10 in each group. The animals were executed after 1 month treatment to collect abdominal aorta. Lipid content in atherosclerosis plaque was evaluated by Oil red O staining and LOX-1 protein expression was examined by immunohistochemistry and Western blot analysis. Results: Bothin vitro andin vivo experiments conifrmed that endothelial cell LOX-1 protein expression was signiifcantly inhibited by ACE2 transfection. The lipid content in ACE2 group was obviously lower than that in EGFP group byin vivo study. Conclusion: ACE2 may inhibit LOX-1 protein expression and therefore reduce the progress of atherosclerosis.