Immune modulation of glycosaminoglycan derived from P. lewisi in TNF-α stimulated cells

Abstract

Poecilocoris lewisi (Korean name: "Kwangdaenolinjae") is a red-striped gold stink bug (insect) which has been used as a crude drug in traditional medicine of East Asia and Korea. In this study, ethanol extract and glycosaminoglycan from P. lewisi (Pl GAG), as an active substance among its components, were investigated for their potential anti-inflammatory actions. They were found to be a potent inducer of nitric oxide (NO) production from calf pulmonary artery endothelial (CPAE) cells and a stimulator of endothelial nitric oxide synthase in a dose-dependent manner. The anti-inflammatory activities were also evaluated by determining the level of adhesion molecules related to atherogenesis and pro-inflammatory cytokines, such as vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), secretory phospholipase A2, and prostaglandin E2, stimulated by tumor necrosis factor (TNF)-α in human umbilical vein endothelial cells (HUVEC). They also showed inhibitory effects on vascular endothelial growth factor (VEGF) production in HUVECs. Matrix metalloproteinases (MMP-2 and 9) were also inhibited by treatment with this extract or glycosaminoglycan. Furthermore, this GAG showed cytotoxicity against CT-26 colon cancer cells whereas having no cytotoxicity in CHO normal cells. Monosaccharide (amino, acidic, neutral monosaccharides) composition of used GAG was characterized by trimethylsilylated GC-MS analysis method.

Keywords: Ethanol extract; Glycosaminoglycan; Immune modulation; P. lewisi.