小鼠自身免疫性心肌炎CXCR3的表达及染料木黄酮的干预作用

Changes of Expression of CXCR3 in autoimmune myocarditis in mice and the interfering effect of Genistein

目的探讨小鼠自身免疫性心肌炎中CXCR3的表达变化及其拮抗剂(染料木黄酮)的干预作用。方法选择6～8周龄Balb/c雄性小鼠64只,其中正常小鼠16只(A组),其余小鼠于第0天和第7天注射提纯的猪心肌肌球蛋白建立实验性自身免疫性心肌炎模型,免疫后随机分为3组:心肌炎模型组(B组)、溶剂二甲基亚砜DMSO组(C组)和染料木黄酮干预组(D组),各组均为16只。分别于初次免疫后14、21d随机处死各组小鼠8只,取材检测相关指标。光镜下观察HE染色的炎症情况,用间接ELISA法检测小鼠血清中肌钙蛋白I(cTnI)水平,用免疫组化和RT-PCR检测小鼠心肌组织中CXCR3蛋白和mRNA表达变化。通过HE染色的炎症情况和血清中cTnI水平评估模型效果,但这两个指标也可以反映CXCR3表达与炎症的关系以及各组心肌炎症损害程度。结果初次免疫后14d,B组炎症评分、cTnI水平、心肌组织中CXCR3蛋白和mRNA表达量均明显高于其他各组(P<0.05),D组较B组炎症和心肌细胞损害程度减轻(P<0.05),C组与B组无差异。21d时B组炎性浸润和心肌细胞的损害较14d时更为明显(P<0.01),D组却较14d时减轻(P<0.05)。结论实验性自身免疫性心肌炎小鼠心脏CXCR3蛋白和mR-NA表达上调,染料木黄酮拮抗CXCR3信号转导通路后心肌炎症减轻,提示CXCR3信号途径可能参与了实验性自身免疫性心肌炎小鼠的心肌炎症过程。

Objective To observe the changes of expression of CXCR3 in autoimmune myocarditis in mice and the interfering effect of Genistein. Methods There were 64 6-8-week-old Balb/c male mice in all. And 16 normal mice were selected as the control group（group A）. The remaining mice,which were immunized with purified cardiac myosin of pigsr heart on day 0 and day 7 to set up experimental autoimmune myocarditis models, were randomly divided into three groups： the model group（group B）, the DM- SO group （group C） and genistein intervention group （group D）. And there were 16 mice in each group. Eight mice in each group were randomly killed separately on day 14 and day 21 after the initial immunization to obtain the materials. Then we observed the inflammatory situation in HE staining under a light microscope and detectd the level of the serum troponin I （cTnl） by indirect ELISA assay. Whatrs more, we used the immunohistochemistry and RT-PCR to detect the changes of the expression of CXCR3 protein and mRNA in myocardial tissue of mice. Results Compared with the control group,the inflammation score,the levels of cTnI, CXCR3 protein and mRNA expression in myocardial tissue of the model group were significantly higher than other groups on the day 14 after initial immunization（P〈0.05）. Inflammation and the damage of myocardial cell in the Genistein intervention group alleviated compared with those in the model group（P〈0.05）. And the DMSO group had no difference with the model group. The inflammatory infiltration and myocardial cell damage were even more evident in the model group on the day 21 than those on the day 14 （P〈0.01）. And compared with those on the day 14, they reduced in the genistein intervention group on the day 21 （P〈0.05）. Conclusion CXCR3 protein and mRNA upregulate in the heart of experimental autoimmune myocarditis mice. And antagonizing the signal transduction by CXCR3 with Genistein can alleviate inflammatory situation in myocardium. It suggests that signaling pathways of CXCR3 may be involved in the process of myocarditis in the experimental autoimmune myocarditis in mice.