The inhibitory effect of (−)-Epicatechin gallate on the proliferation and migration of vascular smooth muscle cells weakens and stabilizes atherosclerosis

Vascular smooth muscle cells (VSMCs) lesions play an important role in atherosclerosis. The latest findings indicate that green tea extract has potential benefits for patients with atherosclerosis, but the components and mechanisms of action are unknown. (−)-Epicatechin gallate (ECG) is the main active ingredient extracted from green tea and has significant biological functions. However, the mechanism of ECG in atherosclerosis remains unclear. Therefore, we investigated the intervention of ECG on VSMCs induced by oxidized low-density lipoprotein (ox-LDL). The results show that ECG reduces the inflammatory response by preventing the overproduction of inflammatory mediators in VSMCs. ECG regulates the cell cycle and down-regulates the expression of proliferating cell nuclear antigen (PCNA) and cyclinD1, and then exerts an anti-proliferative effect. Furthermore, inhibition of the expression of matrix metalloproteinase 2 (MMP-2) and intercellular adhesion molecule 1 (ICAM-1) may be the mechanism by which ECG inhibits the migration of ox-LDL-induced VSMCs. Oil red O staining results show that ECG can improve cell foaming and reduce the content of total cholesterol (TC). In addition, ECG significantly reduces reactive oxygen species activity and also reduces the expression of p-p38, p-JNK, p-ERK1/2, p-IκBα, p–NF–κBp65, and TLR4. These results indicate that ECG has potential clinical applications for preventing atherosclerosis.