Abstract

Background: Peripheral arterial disease (PAD) is often manifest by focal atherosclerotic plaque formation in the infra-inguinal arteries. However, murine models of atherosclerosis in the infra-inguinal arteries are lacking. It is well known that low and oscillatory wall shear stress, which occurs around blockages in PAD, promotes focal atherosclerotic plaque, but this has not been tested in vivo. Piezo1 is a mechanosensitive ion channel associated with hemodynamic changes in the arterial wall, but its role in flow-mediated atherosclerotic plaque deposition is not known. Objective: To develop a flow-mediated murine model of focal atherosclerotic plaque in the femoral arteries. Methods: 8 male and female S129 mice underwent partial femoral artery ligation (Figure A/B). Wall shear stress was calculated from duplex ultrasound imaging (Figure C/D). Atherogenic conditions were imposed with PCSK9 infection and high fat diet; this was initiated 1 week prior to partial femoral ligation. Histologic comparison of the left (partial femoral ligation) and right (normal stable flow) was performed. Results: Low wall shear stress was induced in this model (Figure C/D). Piezo1 expression was decreased in both male and female arteries under these conditions in this model (Figure E). Atherosclerotic plaque was induced by the partial femoral artery ligation but not on the normal stable flow side (Figure F). Conclusions: We have successfully developed a flow-mediated model of focal atherosclerotic plaque in murine femoral arteries. This is associated with downregulation of Piezo1 gene expression. Ongoing work is examining the causative role of Piezo1 on endothelial response to disturbed flow.