基于汗法理论探讨麻黄-桂枝"药对"介导β-AR/cAMP/PKA信号通路治疗银屑病的机制

The occurrence of psoriasis are closely related with keratinocyte(KC).Clinical trials has confirmed that beta AR (adrenaline receptor) blockers can reduce cAMP and aggravate illness. “Mahuang-Guizhi” herbal pair as the classical medicine for diaphoresis, studies have shown that its had similar beta AR agonist. Our preliminary experiments have confirmed for the first time that the herbal pair had the function to intervene the process in the BALB/c mice psoriasis sample model,reduce the guinea pig model psoriatic lesion. AS only beta AR exist on KC, we hypothesized that “Mahuang-Guizhi” herbal pair may play efficacy by mediating beta AR/cAMP/PKA signaling pathways.This study will use beta AR blockers to build guinea pigs model for the in vitro studies. Use IL-22 and IL-17 to induce HaCaT cells for the in vivo studies. From two aspects to observe the curative effect of animal disease model, and the cell proliferation, differentiation, apoptosis as well as  the chemokines secreation.And to explore the relation with the beta AR/cAMP/ PKA pathways. We expect to clarify the possible mechanisms and targets of “Mahuang-Guizhi” herbal pair in the treatment of psoriasis, and provide objective basis for the clinical use of the theory-"in the skin, use diaphoresis method ".

银屑病的发生与角质形成细胞（KC）密切相关。临床实验证实，β-AR（肾上腺素受体）阻滞剂能降低cAMP，加重病情。麻黄-桂枝“药对”作为发汗方中的经典药对，研究表明，其具有类β-AR激动剂作用。我们前期实验首次证实了该“药对”能够干预BALB/c小鼠银屑病样模型的疾病进程，减轻豚鼠银屑病样模型的皮损程度。因KC上AR恰好只表达为β-AR，故我们提出假说：麻黄-桂枝“药对”可能是通过介导β-AR/cAMP/PKA信号通路发挥药效。本研究拟用β-AR阻滞剂进行豚鼠造模并用IL-22和IL-17诱导HaCaT细胞，从体内和体外两个方面观测该“药对”对疾病模型动物的疗效，对细胞增殖、分化、凋亡、分泌趋化因子的影响及与β-AR/cAMP/PKA通路的相关性，以期阐明麻黄-桂枝“药对”治疗银屑病的可能机制和靶点，为“其在皮者，汗而发之”理论的临床运用提供客观依据。

汗法治疗银屑病是从“血”论治银屑病的理论补充，临床运用颇多，我们以发汗经典药对“麻黄-桂枝”干预银屑病样模型，探讨了其发挥效应的可能机制。首先我们分析了麻黄-桂枝“药对”含药血清和水提剂型的主要成分；进一步以IL-22诱导HaCaT细胞，研究药对对诱导后细胞的增殖、分化、凋亡及cAMP/PKA的影响；再以IL-17诱导HaCaT细胞，研究药对对趋化因子、角蛋白分化及cAMP/PKA的影响；根据药对的主要成分，研究了麻黄及单体麻黄碱对银屑病样细胞模型的影响；并进行了体内实验，研究了麻黄及药对对豚鼠银屑病样模型的影响。研究发现一定浓度的麻黄-桂枝“药对”能够抑制IL-22诱导的HaCaT细胞的增殖及分化，可以升高诱导后细胞的cAMP的含量，加入β2-AR抑制剂后，cAMP水平及mRNA的表达降低，考虑药对对β2-AR/cAMP通路产生影响相关，但通路下游PKA未能出现同步效应。一定浓度的麻黄-桂枝“药对”、麻黄碱抑制了IL-17诱导后的CXCL8、CCL20的表达。一定浓度的麻黄及药对水提剂可以抑制豚鼠银屑病样模型的发生，药对组可降低相关炎性细胞因子的表达，但并未通过升高cAMP来发挥效应。