Effect of AVE 0991 angiotensin-(1–7) receptor agonist treatment on elemental and biomolecular content and distribution in atherosclerotic plaques of apoE-knockout mice

• Treatment with AVE 0991 angiotensin-(1–7) receptor Mas agonist in apoE-KO mice was used.
• Elemental and chemical content in atheromas was investigated via XRF and FTIR microspectroscopy.
• Changes in the content and distribution of trace elements were observed.
• Changes in saturation level of lipids and protein secondary structure were observed.

Gene-targeted apolipoprotein E-knockout (apoE-KO) mice display early and highly progressive vascular lesions containing lipid deposits and they became a reliable animal model to study atherosclerosis.The aim of the present study was to investigate the effect of AVE 0991 angiotensin-(1–7) receptor agonist on the distribution of selected pro- and anti- inflammatory elements as well as biomolecules in atherosclerotic plaques of apoE-knockout mice. Synchrotron radiation-based X-ray fluorescence (micro-XRF) and Fourier Transform Infrared (micro-FTIR) microspectroscopies were applied. Two-month-old apoE-KO mice were fed for following four months diet supplemented with AVE 0991 (0.58 μmol/kg b.w. per day). Histological sections of ascending aortas were analyzed spectroscopically. The distribution of P, Ca, Fe and Zn were found to correspond with histological structure of the lesion. Significantly lower contents of P, Ca, Zn and significantly higher content of Fe were observed in animals treated with AVE 0991. Biomolecular analysis showed lower lipids saturation level and lower lipid to protein ratio in AVE 0991 treated group. Protein secondary structure was studied according to the composition of amide I band (1660 cm−1) and it demonstrated higher proportion of β-sheet structure as compared to α-helix in both studied groups.