Anti-atherosclerotic Effect of the Methanol Extract of Sorbus commixta Cortex in the High Cholesterol-Diet Rats

Hypercholesterolemia is a pivotal pathogenic factor for the development and maintenance of atherosclerosis. The present study was designed to evaluate whether the methanol extract of Sorbus commixta cortex (MSC) restores vascular dysfunction in association with the aortic expressions of proinflarnmatory and adhesion molecules in high cholesterol (HC) diet-rats. Chronic treatment with low (100 mg/kg/day) or high doses (200 mg/kg/day) of MSC lowered the increase in plasma levels of triglyceride (TG) and low-density lipoprotein (LDL) cholesterol induced by a cholesterol-enriched diet without affecting on the plasma level of high density lipoprotein (HDL)-cholesterol. Vascular tone attenuated in the HC-diet rats was restored by administration with MSC. Treatment with MSC also suppressed the HC-induced increase in the monocyte chemoattractant protein-1 (MCP-1) and nuclear factor-$_K$B (NF-$_K$B) p65 expressions as well as expressions levels of adhesion molecules including intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (ICAM-1), and E-selectin in aorta. The present study also showed that MSC inhibited the HC-mediated induction of ET-1 and ACE expression. In histopathological examination, aortic segments in the HC-diet rat revealed thickening intima and media, which were blocked by administration with MSC. Taken together, MSC could suppress the development of atherosclerosis in the HC-diet rat model through the inhibition of the aortic expression levels of pro-inflammatory and adhesion molecules.