基于H1R、PAR-2/ TRPV1 痒信号通路探讨马齿苋对急性湿疹的干预作用

目的:探讨马齿苋提取液对急性湿疹大鼠背部皮肤组胺受体1(H1R)、蛋白酶激活受体2(PAR-2)和瞬时感受器电位受体1(TRPV1)表达的影响及其对H1R、PAR-2/ TRPV1 信号通路的调控作用。方法:SD 大鼠30 只,分为正常组、模型组、马齿苋组,各组10 只。采用二硝基氯苯(DNCB)建立急性湿疹模型,正常组除外。造模成功后,各组分别给予相应药物。末次给药后对各组大鼠进行湿疹面积及严重度指数(EASI)评分。免疫组化法检测H1R、PAR-2 和TRPV1 的表达,流式细胞技术测定细胞内钙离子(Ca2+ )浓度。结果:与正常组比,模型组大鼠EASI(P<0.01)、H1R(P<0.05)和PAR-2(P<0.01)的含量、Ca2+浓度(P<0.01)显著增加,TRPV1 增加差异不明显(P>0.05)。与模型组比,马齿苋组大鼠EASI(P<0.01)、H1R(P<0.01)和PAR-2(P<0.01)的含量及Ca2+ 浓度(P<0.05)显著减少,TRPV1 减少差异不明显(P>0.05)。结论:马齿苋可减少H1R、PAR-2 含量及降低Ca2+浓度,发挥治疗急性湿疹的作用,其机制可能是通过降低上游分子H1R、PAR-2 含量,使其下游分子TRPV1 失活,减少Ca2+内流,达到抗瘙痒的作用。

Role of H1R,PAR-2 / TRPV1 itch signal pathway on acute eczema and mechanism study of Portulaca extracts

Objective:To investigate the influence of Portulaca extracts on H1R,PAR-2 and TRPV1 in skins of rats and the regulation mechanism of H1R,PAR-2/ TRPV1 itch signal pathway with atopic eczema.Methods: 30 SD rats were randomly divided into normal control group,model group and Porulaca group,each group contained 10 rats.In addition to the normal group,2,4-dinitrochloro-benzene was used on the rest of group for making rat model with atopic eczema.After the success of the model manufacture,each group was given corresponding drugs.After the last administration,EASI was evaluated.The levels of H1R,PAR-2 and TRPV1 in rats skins were detected by immunohistochemical method.Ca2+ concentration was analyzed by flow cytometry.Results: Compared with normal control group,EASI(P<0.01),the levels of H1R(P<0.05) and PAR-2(P<0.01),and Ca2+ concentration(P<0.01) of rats in model group were significantly increased.The levels of TRPV1 were not increased obviously (P>0.05).Compared with model group,EASI (P<0.01),the levels of H1R(P<0.01) and PAR-2(P<0.01),and Ca2+ concentration (P<0.05) of rats in Porulaca group were significantly reduced,and the levels of TRPV1 were not decreased obviously (P>0.05).Conclusion: Purslane could reduce the levels of H1R,PAR-2 and Ca2+ concentration to treat the acute eczema.The mechanism may be to lose the activation of downstream molecule TRPV1 and reduce the inflow of Ca2+ by reducing the levels of upstream molecules H1R and PAR-2,then to achieve the effect of anti itch.