Angiotensin-(1-7) receptor Mas agonist ameliorates progress of atherosclerosis in apoE-knockout mice

Our interest focused on an open question whether AT-(1-7), nonpeptide receptor agonist: AVE 0991, is able to ameliorate atherosclerosis. We used an apolipoprotein E (apoE) - knockout mice model of atherosclerosis. Experimental groups received the same diet as control, mixed with: AVE 0991 at a dose of 0.58 μmol/kg b.w./day, perindopril at a dose of 0.4 mg/kg b.w./day or with tiorphan at a dose of 2.5 mg/kg b.w./day. A-779 [(D-alanine)-angiotensin (1-7)] was given at a dose of 3.3 mg/kg b.w., 3 times a week i.p. Measured by "en face" method, the percentage of occupied by Sudan IV-stained surfaces were as follows: 14.2±1.9 % in control group, whereas in AVE 0991-treated as well as in perindopril-treated groups percentages were statistically significantly lower. In tiorphan group there was no change comparing to control group, whereas in A-779 group percentage was statistically significantly higher. "Cross-section" of aortic roots revealed also the difference in atherosclerotic lesions. The mean surfaces, occupied by oil red O-stained changes were: 91.213±8.123 μm(2) in control group, while in AVE 0991-treated as well as in perindopril-treated groups lesions were statistically significantly lower. In tiorphan group there was no change; however, in A-779 group lesions were statistically significantly higher. Measured by real time RT-PCR relative p22phox (submit of NADPH oxidase) expression was significantly decreased in AVE 0991-treated mice. As revealed by flow cytometry, the expression of co-stimulatory molecules: CD86, CD80 and CD40 on both dendritic cells (CD11c+) and macrophages (F4/80+) was reduced in AVE 0991-treated group, which correlated with decreased expression of CD69 activation marker on CD4+T cells. In our report we showed the beneficial effect of AVE 0991 on atherogenesis in gene-targeted mice