| 摘要: | 當身體受到外來物質感染(如細菌內毒素LPS)或組織受傷，將刺激巨噬細胞活化，並釋出免疫介質，如一氧化氮(NO, nitric oxide)、介白素-6 (IL-6, interleukin-6)、腫瘤壞死因子α (TNF-α, tumor necrosis factor alpha) 與基質金屬蛋白酶(MMPs, matrix metalloproteinases)等，幫助病原體的清除，並藉由免疫細胞的調控，維持免疫功能的平衡。坊間廣泛使用的狼尾草(Pennisetum purpureum S.)生機飲食，被宣稱具健康促進之免疫調節的作用，然而尚無科學之根據，因此本研究探討狼尾草台畜二號酒精或水萃取物對於RAW264.7巨噬細胞免疫調節的影響，以及對於LPS存在下抗發炎的影響。狼尾草台畜二號市售粉末，以99.8 %酒精或二次蒸餾水室溫萃取24小時後的萃取物，於LPS (100 ng/ml)存在或不存在下及狼尾草酒精萃取物(0.625, 1.25, 2.5 mg/ml)或水萃取物(5, 10, 20 mg/ml)處理RAW264.7巨噬細胞24小時後，收集培養基及細胞進行分析。結果顯示，酒精萃取物可增加MMP-9的活性，且可降低LPS所誘導的NO、IL-6、TNF-α生成，且伴隨著iNOS蛋白質、CD14 mRNA表現量的降低。然而對LPS所誘導的NF-κB DNA結合活性無影響。狼尾草水萃物內含nitrite，並可增加巨噬細胞IL-6、TNF-α的產生，然而對iNOS蛋白質表現量以及免疫相關基因iNOS、CD14、TLR4 mRNA無顯著影響，此外水萃物無法對LPS所誘導的NO、IL-6、TNF-α產生無顯著影響。總言之，狼尾草具調節免疫的能力，其中酒精萃取物可增加RAW 264.7巨噬細胞MMP-9活性，水萃物可增加IL-6、TNF-α的產生。同時酒精萃取物可降低LPS誘導RAW 264.7巨噬細胞的NO、IL-6、TNF-α、iNOS蛋白質與CD14 mRNA表現量，而具抗發炎作用。因此認為狼尾草之水萃物具有增加健康者的免疫能力之潛力；酒精萃取物則具有降低發炎者的發炎介質釋出之潛力。
Napiergrass Taishigrass No.2 (Pennisetum purpureum S.) is one of livestock forage species in Taiwan. Recently, napiergrass is considered as one of natural organic diet materials and used to consume for health promotion. However, the effects of napiergrass on health promotion has not been investigated. The aim of this study was to explore the effects of napiergrass Taishigrass No.2 on the modulation of immunity in RAW 264.7 macrophages and lipopolysaccharide (LPS)-induced RAW 264.7 macrophages inflammation. Napiergrass Taishigrass No.2 freeze dry powder was bought from Baoyuan company (Taichung, Taiwan). Napiergrass Taishigrass No.2 was extracted by 99.8% ethanol or water in room temperature for 24 h and condensed for cell culture used. Cells were treated with in the presence or absence of LPS (100 ng/ml) and ethanol extracts of napiergrass (0, 0.625, 1.25, 2.5 mg/ml) or water extracts (0, 5, 10 20 mg/ml) for 24 h. Ethanol extracts of napiergrass increased MMP-9 activities and MMP-9 mRNA expression, but had no effect on MMP-2 activities, implying that napiergrass may have immunomodulatiotory effects. Ethanol extracts of napiergrass suppressed nitric oxide (NO), interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α), inducible nitric oxide synthase (iNOS) protein expression and CD14 mRNA expression in LPS-induced RAW 264.7 macrophages, implying that napiergrass may have anti-inflammation activities. However ethanol extracts of napiergrass couldn’t decrease LPS-induced NF-κB DNA binding activity in RAW 264.7 macrophages. In the presence or absence LPS-induced inflammation condition, water extracts of napiergrass increased NO concentration in a dose dependent manner. Under cell-free condition, water extracts of napiergrass showed similar NO results as cell condition. Water extracts had no effect to iNOS protein expression, MMP-9 activities, MMP-2 activities and inflammatory associated mRNA expression. However water of napiergrass extracts increased IL-6 and IL-6 production in RAW 264.7 macrophages. Overall, the results obtained showed that napiergrass have immunomodulatiotory effects by increasing MMP-9 activities, IL-6 and TNF-α production on RAW 264.7 macrophages. |
