臺灣款冬之抗發炎活性研究
The Anti-inflammation principle constituents of Petasites formosanus Kitam.
中文摘要
菊科植物被報導指出具有諸多生理活性，如抗腫瘤、抗菌、抗虐以及抗發炎等…，且台灣菊科植 物種類繁多，因此本研究將選用30 種菊科植物，將其利用 50%甲醇迴流萃取，並利用酯多糖 來誘導老鼠RAW 264.7 巨噬細胞表現 iNOS 及釋放一氧化氮，並以 Griess reaction 分析方 法來測NO 含量變化。結果顯示：大花咸豐草、南美蟛蜞菊、台灣款冬具有明顯的抑制 NO 產生，
其IC50 分別為 72.09、41.08、29.57 μg/ml。其中又以臺灣款冬葉萃取物對 iNOS 的表現具有 顯著抑制作用，且於Carrageenan 誘導小鼠足掌發炎、醋酸扭體和輻射熱源法等動物實驗中，
結果顯示：餵服400 mg/kg 之實驗組，在誘導後的 4、5、6 小時皆具有意義的抑制足腫反應；
而餵服100 mg/kg 即有意義的抑制疼痛。進而利用 NO 抑制活性追縱方式，分離臺灣款冬葉之 消炎和止痛活性成份。分離純化結果得到isopetasin、S-isopetasin、S-petasin 和 caffeic acid methyl ester 等活性成份。再以體內、體外試驗評估天然物消炎、止痛作用，結果顯示：
S-isopetasin 和 S-petasin 皆會抑制 NO 的產生，其 IC50 分別為 4.67 μM、4.45 μM，且 S- isopetasin 和 S-petasin 具有抑制 iNOS 及 COX-2 的表現；於體內實驗中，餵服 5mg/kg 即 具有很明顯的消炎、止痛作用，其中以S-isopetasin 作用較為明顯，所以 S-isopetasin 是一 個具有開發為消炎止痛潛力的天然物，而臺灣款冬是經濟價值高的藥用植物。
英文摘要
In Taiwan, several species of Compositae plants are used as Chinese herbs. In this study, 30 kinds of Composite family plants were extracted by 50% MeOH, the anti-inflammatory and analgesic effects of these extracts were measured by in vitro and in vivo models. The nitric oxide (NO) production which induced by LPS- stimulated RAW 264.7 macrophage and quantitatively deteproduction by Griss reaction. Results showed that Bidens pilosa L. var. radiata Sch., Petasites
formosanus Kitam., Wedelia trilobata (L.) Hitchc. suppressed NO production from lipopolysaccharide（LPS）induced RAW 264.7 cells and the IC50 values were 72.09, 29.57, 41.08 μg/ml, respectively. P. formosanus (PF) inhibited inducible nitric oxide synthase (iNOS) a expression on LPS induced RAW 264.7 cells but COX-2 not. Therefore, the anti-inflammation effects of PF were evaluated by carrageenan-induced paw edema in mice. PF also significantly inhibited the paw edema after treatment with 400 mg/kg. The analgesic activity evaluated by Acetic acid-induce writhing response in mice and Radiant heat method. PF also
significantly exhibited analgesic effects after treatment with 100mg/kg.
Continuously, the anti-inflammation principle constituents of PF were isolated by column chromatography combined bioassay-guided fractionation. Four kinds of natural products, isopetasin, S-isopetasin, s-petasin, caffeic acid methyl ester
were obtained and S-isopetasin and S-petasin more significant inhibited NO production than the others and IC50 values were 4.67 μM and 4.45 ?nμM and inhibited iNOS and COX-2 expression in LPS induced-RAW 264.7 cells. In vivo studies, S-isopetasin also exhibited anti-inflammatory and analgesic effects and more than effects than S-petasin. Therefore, we suggested S-isopetasin was major anti-inflammatory and analgesic components in PF and was a good lead
compound.
