【作者】 程瑶；

【导师】 张雪梅；

【作者基本信息】 延边大学 ， 基础兽医学， 2014， 硕士

【摘要】 目的：本试验采用传统中药蒲公英的主要成分蒲公英甾醇为研究对象,探讨蒲公英甾醇的体外抗炎作用及其相关作用机制。方法：本试验分为空白组、模型组、蒲公英甾醇(低、中、高剂量)组。通过脂多糖(LPS)刺激小鼠腹腔巨噬细胞建立体外炎症体系,采用MTT法进行细胞毒性测定,确定蒲公英甾醇安全使用剂量；通过Griess法测得炎症介质NO的含量,通过ELISA法测得炎症介质PGE2的含量；通过RT-PCR检测RAW264.7细胞中COX-2和iNOS mRNA的表达；通过Western blot法检测iNOS和COX-2蛋白的表达,并检测ERK1/2、JNK和p38MAPK及其磷酸化水平的表达。结果：1.蒲公英甾醇抗炎作用检测结果显示：与模型组相比较,蒲公英甾醇剂量组炎症反应明显减弱,显著抑制LPS诱导的小鼠RAW264.7细胞NO和PGE2的生成；蒲公英甾醇分别不同程度的抑制了iNOS和COX-2mRNA和蛋白的表达,且呈一定的剂量依赖关系。2.蒲公英甾醇抗炎机制检测结果显示：蒲公英甾醇显著的抑制了LPS诱导的小鼠RAW264.7细胞p38和ERK1/2激酶的磷酸化,并呈剂量依赖关系,但对JNK激酶磷酸化的抑制作用不显著。结论：蒲公英甾醇通过抑制LPS诱导的小鼠RAW264.7细胞ERK1/2和p38MAPK信号传导通路抑制iNOS和COX-2mRNA和蛋白表达,从而降低细胞炎症介质NO和PGE2的释放,发挥其体外抗炎作用。更多还原

【Abstract】 Objective:We used traditional taraxasterol isolated from Herba Taraxaci as object, and studied anti-inflammatory effects and its mechanism in vitro.Methods:The experiment divided into blank groups, model groups, taraxasterol groups (low, medium and high). Anti-inflammatory system was established in vitro through the mouse peritoneal macrophages induced by LPS. Cell toxicity was measured by MTT method, and dose was determined. NO concentration was measured by Griess method. PGE2concentration was measured by ELISA method. iNOS and COX-2mRNA expressions were determined by RT-PCR method. COX-2and iNOS protein expressions were determined by Western blot method, and determined the phosphorylation levels of ERK, JNK, p38protein expressions.Results:1. The anti-inflammatory of taraxasterol test showed that was decrease significantly comparing with model groups, the degree of inflammation taraxasterol groups (low, medium and high), taraxasterol significantly inhibited the release of NO and PGE2in RAW264.7cells; taraxasterol of different dose inhibited the expression of iNOS, COX-2mRNA and proteins in a dose-dependent relationship.2. The mechanism of anti-inflammatory test showed that taraxasterol inhibited the phosphorylation of p38, ERK1/2and JNK kinases in mouse RAW264.7cells induced by LPS, in a dose-dependent relationship.Conclusion:Taraxasterol inhibit the expression of INOS, COX-2mRNA and proteins by inhibiting MAPK, p-ERK1/2and p-p38pathway of the RAW264.7cells induced by LPS, and reduce the release of inflammatory mediator of the cells.更多还原