流行病學、臨床試驗及動物試驗等研究巳証實氧化低密度脂蛋白(ox-LDL)是動脈粥狀硬化危險因子，其作用機轉之一是ox-LDL能誘導內皮細胞黏著因子表現，吸引單核球與內皮細胞結合。本實驗動機為探討杭菊熱水萃出物(hot water extract of yellow Chrysanthemum morifolium Ramat, HYC)與95%乙醇萃出物(95% ethanol extract of yellow Chrysanthemum morifolium Ramat, EYC)對ox-LDL誘導內皮細胞黏著因子ICAM-1表現之影響。試管試驗結果顯示: HYC和EYC以劑量關係抑制銅離子所誘發LDL氧化反應中共軛二烯(conjugated diene)和TBARS (thiobarbituric acid-reactive substances)之生成( p <0.05 )。細胞試驗也顯示：HYC和EYC分別在0.25-1 mg/ml和25-250 μg/ml間以劑量關係抑制細胞內ICAM-1的表現，相較對照組細胞，1 mg/ml HYC與250 μg/ml EYC抑制效果分別為35.4%及16.9%；除胞內ICAM-1表現量外，HYC和EYC也可抑制細胞表面ICAM-1的表現，最佳抑制效果以100 μg/ml和25 μg/ml最佳，分別有22.4%及14.7%的抑制效果；DCF-DA (2′,7′- dihydrofluorescein diacetate)分析結果也顯示HYC與EYC可以劑量關係抑制胞內過氧化物生成。HYC及EYC的總酚類化合物和類黃酮含量：HYC分別為58.7 ± 3.4 mg gallic acid equivalents和22.2 ± 1.1 mg quercetin equivalents/g dry solvent extract，EYC則為44.5 ± 3.3 mg gallic acid equivalents和19.3 ± 1.1 mg quercetin equivalents/g dry solvent extract，總酚類及類黃酮含量均是HYC高於EYC。綜合以上結果，HYC和EYC具有保護LDL氧化的作用，在保護內皮細胞作用上，杭菊也可抑制細胞內和細胞膜表面黏著因子ICAM-1的表現以及胞內過氧化物的生成。
Oxidized low density lipoprotein (ox-LDL) has been known to be one of the atherogenic risk factors by numerous epidemiological, clinical, and animal studies. Ox-LDL induction of endothelial adhesion molecule expression is required for monocytes adhereing to endothelial cells. In this study, we intended to examine the effect of hot water extract (HYC) and 95% ethanol extract of yellow chrysanthemum morifolium Ramat (EYC) on ox-LDL-induced ICAM-1 expression in human umbilical vein endothelial cells (HUVECs). Result showed that HYC and EYC dose-dependently inhibit conjugated diene formation and TBARS in LDL induced by Cu2SO4 (p <0.05). Immunoblot assay showed that HYC (0.25-1 mg/ml) and EYC (25-250 μg/ml) inhibit intracellular ICAM-1 expression in a dose-dependent manner. An inhibition of 35.4% and 16.9% ICAM-1 expression was noted in cells treated with 1 mg/ml HYC and 250 μg/ml EYC, respectively .In addition of cellular ICAM-1, the cell surface expression of ICAM-1 was also inhibited by 22.4% and 14.7% in cells treated with 100 μg/ml HYC and 25 μg/ml EYC , respenctively. DCF-DA assay indicated HYC and EYC dose-dependently inhibit intracellular ROS production. The contents of phenolic compounds and flavonoids were 58.7 ± 3.4 mg gallic acid equivalents, 22.2 ± 1.1 mg quercetin equivalents/g dry HYC and were 44.5 ± 3.3 mg gallic acid equivalents and 19.3 ± 1.1 mg quercetin equivalents/g of dry EYC. Both phenolic compounds and flavoinids contents of HYC were higher than that of EYC. These findings suggest that both HYC and EYC effectively protect LDL against Cu2SO4 induced have antioxidant activity oxidation, and they are also protect in suppression of intracellular and cell surface ICAM-1 expression and intracellular ROS production in HUVECs.
