Protective Effect of Allium tuberosum Extract on Vascular Inflammation in Tumor Necrosis Factor-α-induced Human Vascular Endothelial Cells

ABSTRACT

BACKGROUND: Endothelial adhesion molecule expression induced by pro-inflammatory cytokine plays an important role in vascular endothelial cell injury, leading to vascular disease. Allium tuberosum (AT), which is used as a functional food, has a thrombolytic effect. It contains vitamin A, vitamin C, carbohydrate, calcium, iron, and phosphorus. There are many carotenes that turn into vitamin A in the body. Also, it helps blood circulation and stimulates metabolism. The purpose of the this study was to estimate the anti-inflammatory effects of the AT extract. METHODS: Human vascular endothelial cells were pre-treated with 100 μg/mL AT extract for 30 minutes and subsequently co-treated with TNF-α (10 ng/mL) and AT extract (100 μg/mL) for 1, 4, and 6 hours. After treatment, the cells were lysed and used for quantitative reverse transcription PCR, Western blot analysis, and monocyte adhesion assay. RESULTS: We examined the effect of the AT extract on inflammatory gene expression in TNF-α-induced human umbilical vein endothelial cells (HUVECs). The extract reduced the expression levels of mRNA and protein of intercellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1 in TNF-α-stimulated HUVECs. It also inhibited the TNF-α-induced phosphorylation of the NF-κB p65 subunit and degradation of IκBα. Furthermore, the AT extract prevented the increased adhesion capacity of monocyte to TNF-α-stimulated vascular endothelial cells by reducing ICAM-1 and VCAM-1 expression. CONCLUSIONS: The AT extract has preventive and anti-inflammatory effect against vascular disease and has potential for supporting prevention against the early process of atherosclerosis.