Effects of Shenlian extract on experimental atherosclerosis in ApoE-deficient mice based on ultrasound biomicroscopy

Abstract

Background: This study directly and dynamically investigated the effects of SL extract (i.e., a combination of Radix Salviae miltiorrhizae and Andrographis paniculata extract) on plaque progression in vivo by high resolution ultrasound biomicroscopy (UBM). Methods: An atherosclerosis model was established by placing a perivascular collar on the right common carotid artery in apolipoprotein E-deficient (ApoE-/-) mice. Thickness, plaque area and local blood flow were observed by UBM, pathological changes were observed by histochemical staining, and lipid levels were measured by respective commercially available kits. Results: Compared with the model group, the SL extract groups showed reduced wall thickness of the aortic arch (GC: P=0.001, P=0.002, and P<0.001; LC: P<0.001, P<0.001, and P<0.001; BC: P=0.027, P=0.017, and P=0.003; respectively), which presented with retarded plaque progression of the cartoid artery with concordantly increased blood flow (P=0.002 and P<0.001) as visualized in vivo by UBM. Histological analysis confirmed the reduction of carotid atherosclerosis. Conclusions: The SL extract inhibited the formation of atherosclerotic plaques in an ApoE-/- mice model by UBM analysis, and did so by effects that ameliorated local blood flow and improved blood lipid levels.