桑白皮抗炎活性成分的分离及抗炎机制研究

Isolation of Active Compounds from Cortex Mori and Its Mechanism on Anti-Inflammatory

目的:研究桑白皮中抗炎的活性物质并初步确定其抗炎机制。方法:利用硅胶柱层析等方法分离抗炎活性物质并利用波谱分析进行结构鉴定;以RAW264.7细胞为研究对象,构建LPS诱导体外炎症模型,利用ELISA法研究活性成分桑根酮-O和桑根酮-C对炎症细胞因子肿瘤坏死因子-a(TNF-a),白细胞介素-1b(IL-1B),白细胞介素-6(IL-6),白细胞介素-10(IL-10)的作用;利用免疫蛋白印迹(Western blot)法研究了桑根酮-O和桑根酮-C对RAW264.7细胞i NOS、COX-2和磷酸化细胞外信号调节激酶(p-ERK)蛋白表达的影响。结果:从桑白皮中分离获得2种抗炎活性物质,经波谱鉴定为桑根酮-O和桑根酮-C。体外抗炎结果表明:能够下调促炎症因子TNF-a、IL-1B、IL-6的合成,上调抑炎因子IL-10的合成,并抑制了RAW264.7细胞中i NOS、COX-2、p-ERK蛋白的表达。结论:桑根酮-G和桑根酮-O均具有一定的抗炎作用,其抗炎机制可能调节促炎因子合成,以及NF-κB和COX-2蛋白表达有关。

Objective： To isolate the active compounds from Cortex Mori and evaluate the anti-inflammatory effects and mechanism of the compounds on RAW 264.7 cells in vitro.Methods ：Bioassay-guided fraction was used to isolate the active compounds from C.Mori.The structure of the active compound was determined by various spectroscopic analyses.The expression levels of TNF-α,IL-1β,IL-6 and IL-10 in cell supernatant were measured by ELISA method and the COX-2 and NF-κB protein expressions in RAW264.7 cells were analyzed by Western blotting.Results： Two active compounds were isolated from C.Mori and identified as kuwanon G and kuwanon O.The in vitro anti-inflammatory results showed that kuwanon G and kuwanon O could significantly decreased the expressions of TNF-α,IL-1β,IL-6 as well as the COX-2 and NF-κB protein in LPS-stimulated RAW264,in dose-dependent manners（P〈0.05）.In contrast,the concentration of IL-10 was significantly increased when the cells were treated with kuwanon G and kuwanon O.Conclusion： Kuwanon G and kuwanon O both showed obvious anti-inflammatory effects and their mechanism may be related with the down-regulation of proinflammatory cytokine.