First Author | Thatcher SE | Year | 2014 |
Journal | Arterioscler Thromb Vasc Biol | Volume | 34 |
Issue | 12 | Pages | 2617-23 |
PubMed ID | 25301841 | Mgi Jnum | J:230466 |
Mgi Id | MGI:5760112 | Doi | 10.1161/ATVBAHA.114.304613 |
Citation | Thatcher SE, et al. (2014) Angiotensin-converting enzyme 2 decreases formation and severity of angiotensin II-induced abdominal aortic aneurysms. Arterioscler Thromb Vasc Biol 34(12):2617-23 |
abstractText | OBJECTIVE: Angiotensin-converting enzyme 2 (ACE2) cleaves angiotensin II (AngII) to form angiotensin-(1-7) (Ang-(1-7)), which generally opposes effects of AngII. AngII infusion into hypercholesterolemic male mice induces formation of abdominal aortic aneurysms (AAAs). This study tests the hypothesis that deficiency of ACE2 promotes AngII-induced AAAs, whereas ACE2 activation suppresses aneurysm formation. APPROACH AND RESULTS: ACE2 protein was detectable by immunostaining in mice and human AAAs. Whole-body deficiency of ACE2 significantly increased aortic lumen diameters and external diameters of suprarenal aortas from AngII-infused mice. Conversely, ACE2 deficiency in bone marrow-derived cells had no effect on AngII-induced AAAs. In contrast to AngII-induced AAAs, ACE2 deficiency had no significant effect on external aortic diameters of elastase-induced AAAs. Because ACE2 deficiency promoted AAA formation in AngII-infused mice, we determined whether ACE2 activation suppressed AAAs. ACE2 activation by administration of diminazene aceturate (30 mg/kg per day) to Ldlr(-/-) mice increased kidney ACE2 mRNA abundance and activity and elevated plasma Ang-(1-7) concentrations. Unexpectedly, administration of diminazene aceturate significantly reduced total sera cholesterol and very low-density lipoprotein-cholesterol concentrations. Notably, diminazene aceturate significantly decreased aortic lumen diameters and aortic external diameters of AngII-infused mice resulting in a marked reduction in AAA incidence (from 73% to 29%). None of these effects of diminazene aceturate were observed in the Ace2(-/y) mice. CONCLUSIONS: These results demonstrate that ACE2 exerts a modulatory role in AngII-induced AAA formation, and that therapeutic stimulation of ACE2 could be a benefit to reduce AAA expansion and rupture in patients with an activated renin-angiotensin system. |