目的 基于脂多糖诱导小鼠单核巨噬细胞（RAW 264.7）构建的体外细胞炎症模型，探讨牡蒿Artemisia japonica Thunb.水提物的抗炎作用及其机制。方法 通过CCK-8法检测牡蒿水提物对RAW 264.7细胞活力的影响以筛选合适的牡蒿水提物给药质量浓度。采用脂多糖200 ng/mL诱导RAW 264.7细胞建立体外炎症细胞模型。将细胞分为对照组、模型组和牡蒿水提物（240、480、960μg/mL）组，用Griess试剂法检测RAW 264.7细胞一氧化氮（NO）释放水平，ELISA法检测细胞白细胞介素（IL）-6、IL-1β含量。采用Western blotting法检测诱导型一氧化氮合成酶（iNOS）、环氧合酶-2(COX-2)以及Toll样受体4(TLR4)/核因子-κB(NF-κB)信号通路中TLR4、核因子κB抑制蛋白α(IκBα)、p-IκBα、p65蛋白（p65）、p-p65蛋白相对表达量。结果 牡蒿水提物质量浓度为0～960μg/mL时对RAW 264.7细胞活力没有显著影响。与模型组相比，牡蒿水提物480、960μg/mL组能显著抑制IL-6的释放以及COX-2的蛋白相对表达量（P<0.01）；各质量浓度牡蒿水提物均能显著抑制NO、IL-1β的释放，iNOS、p-IκBα、p65、p-p65蛋白的表达以及IκBα蛋白的降解（P<0.01）。结论 牡蒿水提物能抑制脂多糖诱导的RAW 264.7细胞炎性因子的分泌，其作用机制与抑制炎性蛋白iNOS和COX-2的表达及TLR4/NF-κB信号通路的激活有关。

Objective To explore the effects and mechanisms of A. japonica water extract on lipopolysaccharide-induced RAW 264.7macrophages model. Methods CCK-8 colorimetric method was used to select the appropriate concentration of A. japonica on the activity of RAW 264.7 macrophages. RAW 264.7 cells were induced by lipopolysaccharide 200 ng/mL to establish in vitro inflammatory cell model. Cells were divided into control group, model group, and A. japonica（240, 480, and 960 μg/mL） groups.Griess assay was used to assess NO concentration, IL-1β, and IL-6 content was measured by ELISA. The expression of iNOS, COX-2, and TLR4/NF-κB pathway-related proteins（TLR4, IκBα, p-IκBα, p65, p-P65） were detected by Western blotting. Results A.japonica had no significant effect on the viability of RAW 264.7 cells at the concentrations of 0 — 960 μg/mL. Compared with model group, A. japonica water extract 480 and 960 μg/mL groups significantly inhibitory effects on the release of IL-6 and protein expression of COX-2（P＜0.01）. Each dose group of A. japonica water extract displayed favorable inhibitory decreased effects on release of NO and IL-1β, expression of iNOS, p-IκBα, p65, and p-p65 proteins and degradation of IκBα. Conclusion A. japonica water extract could inhibit lipopolysaccharide-induced secretion of inflammatory factors in RAW 264.7 cells, the mechanism of which is related to inhibiting the expression of inflammatory proteins iNOS and COX-2 and inhibiting the activation of TLR4/NF-κB signaling pathway.

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国家自然科学基金资助项目(32260925); 贵州省科技计划项目(黔科合基础-ZK[2022]一般507); 贵州中医药大学大学生创新创业训练计划项目[贵中医大创合字(2021)84号