The protective effect of Prunella vulgaris ethanol extract against vascular inflammation in TNF-α-stimulated human aortic smooth muscle cells

Atherosclerosis, which manifests as acute coronary syndrome, stroke, and peripheral arterial diseases, is a chronic inflammatory disease of the arterial wall. Prunella vulgaris, a perennial herb with a worldwide distribution, has been used as a traditional medicine in inflammatory disease. Here, we investigated the effects of P. vulgaris ethanol extract on TNF-alpha-induced inflammatory responses in human aortic smooth muscle cells (HASMCs). We found that P. vulgaris ethanol extract inhibited adhesion of monocyte/macrophage-like THP-1 cells to activated HASMCs. It also decreased expression of intercellular adhesion molecule-1, vascular cell adhesion molecule-1, E-selectin and ROS, No production in TNF-alpha-induced HASMCs and reduced NF-kB activation. Furthermore, P. vulgaris extract suppressed TNF-alpha-induced phosphorylation of p38 mitogen-activated protein kinase (MAPK) and extracellular signal-regulated kinase (ERK). These results demonstrate that P. vulgaris possesses anti-inflammatory properties and can regulate TNF-alpha-induced expression of adhesion molecules by inhibiting the p38 MAPK/ERK signaling pathway.