Jung Joo Hong

Inhibition of cytokine-induced vascular cell adhesion molecule-1 expression; possible mechanism for anti-atherogenic effect of Agastache rugosa

Adhesion molecules such as vascular cell adhesion molecule‐1 (VCAM‐1) play an important role during the early stages of atherogenesis. Agastache rugosa has an anti‐atherogenic effect in low density lipoprotein receptor −/− mice. Moreover, A. rugosa reduced macrophage infiltration and VCAM‐1 expression has been localized in aortic endothelium that overlies early foam cell lesions. This study ascertained that tilianin (100 μM), a major component of A. rugosa, inhibits the tumor necrotic factor‐α (TNF‐α)‐induced expression of VCAM‐1 by 74% in cultured human umbilical vein endothelial cells (HUVECs). Also, tilianin (100 μM) reduced TNF‐α‐induced activation of nuclear factor‐κB in HUVECs.

Dietary hematein ameliorates fatty streak lesions in the rabbit by the possible mechanism of reducing VCAM-1 and MCP-1 expression

Hematein is a compound isolated from Caesalpinia sappan that has been used in oriental medicine as both an analgesic and an anti-inflammatory agent. In this study, we examined the anti-atherogenic potential of hematein using cholesterol-fed New Zealand White (NZW) rabbits. NZW rabbits were divided into a hematein-supplemented (0.05% in diet) group (n=6), a probucol-supplemented (0.25% in diet) group (n=6), and a control group (n=6). After 8 weeks of treatments, the extent of the atherosclerotic lesions was significantly reduced in the hematein-supplemented group and the probucol-supplemented group without changing plasma lipoprotein levels. Hematein and probucol prevented the up-regulation of the vascular cell adhesion molecule-1 (VCAM-1) expression on the descending aorta induced by cholesterol diet. In culture, hematein also significantly inhibited the secretion of soluble VCAM-1 and of monocyte chemotactic protein-1 (MCP-1) respectively induced by tumor necrotic factor alpha (TNF-alpha) and mildly oxidized low density lipoprotein in human umbilical vein endothelial cell (HUVEC) culture. Also, hematein inhibited monocyte adhesion to endothelial cell and the activation of NF-kappaB in HUVECs stimulated with TNF-alpha. The results of the present study suggest that the anti-atherogenic effect of hematein is not related to control of the plasma lipid profile but probably related to the inhibition of VCAM-1 and MCP-1 expression resulting in an amelioration of lesion development in the rabbit.

An outbreak of toxoplasmosis in squirrel monkeys (Saimiri sciureus) in South Korea

Toxoplasma gondii (T. gondii) is an intracellular protozoan parasite that can infect warm‐blooded animals including humans. New World monkeys, such as squirrel monkeys, are more susceptible to T. gondii than Old World monkeys, often developing fatal disease.