从Notch信号通路探讨宣肺平喘方调节Th17/Treg细胞平衡治疗哮喘的机制

Asthma is a common clinical refractory respiratory diseases, the imbalance of Th17/Treg is a new immune mechanism in asthma. A kind of hospital preparations which named Xuanfei Pingchuan formula was created based on the TCM theory of phlegm blocking the airway and lung losing its clearingaction. This formula has shown a significant effect in the treatment of asthma, but the exact mechanism remains unclear. Our previous study shows that this formula can effectively improve airway inflammation, alleviate lung injury and recover the balance of Th17/Treg in asthmatic mice, meanwhile, it can also suppress the expression of NICD, Hes-1 protein of Notch signaling pathway in CD4+ cells. Whether Xuanfei Pingchuan formula restore the balance of Th17/Treg via Notch signaling pathway needs to be verified by further experiments. The project intends to establish OVA induced asthmatic mice, in order to evaluate the efficacy of Xuanfei Pingchuan formula depending on the detection of inflammatory factor, immune cells, Notch pathway protein expression. Simultaneously, through the MACS technology, reseaching the interaction between Th17, Treg cells and key factors of Notch signaling pathway in molecular level. And then clarify the treatment mechanism of Xuanfei Pingchuan formula on asthma. It may provide a new idea on seeking new drugs for asthma.

哮喘是临床常见难治性呼吸道疾病，Th17/Treg细胞失衡是哮喘新的免疫学发病机制。宣肺平喘方是根据哮喘痰阻气道、肺失宣降的病机而设定的院内制剂，临床上治疗哮喘疗效显著，但其具体机制尚不明确。课题组前期研究发现，该方能显著改善哮喘模型小鼠气道炎症，减轻肺组织黏膜损伤，恢复Th17/Treg细胞平衡，同时还能抑制肺组织中CD4+T细胞Notch信号通路相关蛋白NICD、Hes-1的表达。宣肺平喘方是否通过介导Notch信号通路恢复Th17/Treg细胞平衡有待进一步实验验证。本项目拟建立OVA致敏哮喘小鼠模型，通过检测炎性因子、免疫细胞及Notch通路蛋白表达的变化评价宣肺平喘方治疗哮喘的药效；同时磁珠分选T细胞，从分子水平研究Th17、Treg细胞及Notch信号通路关键因子的相互影响，进而阐明宣肺平喘方治疗哮喘的作用机理，为新的哮喘治疗药物的寻找提供新的思路。

Th17/Treg细胞失衡是新的哮喘发病机制。宣肺平喘方是根据哮喘痰阻气道、肺失宣降的病机而设定的院内制剂，被长期有效地运用于临床。本课题采用卵蛋白(OVA)腹腔注射建立哮喘小鼠模型，发现宣肺平喘方能有效改善哮喘模型小鼠的气道炎症，保护肺组织黏膜损伤，降低血清中炎症因子IL-4、TNF-α的含量，增加血清抑炎因子TGF-β的含量，同时Notch信号通路中的NICD、Hes-1蛋白水平明显下降，由此可推测宣肺平喘方是通过干预Notch信号通路中的NICD、Hes-1蛋白来恢复Th17/Treg细胞平衡，抑制炎症反应。进一步研究发现，宣肺平喘方还能调节肺泡液和肠道菌群失调。本研究从动物水平研究Th17、Treg细胞及Notch信号通路关键因子的相互影响，进而阐明宣肺平喘方治疗哮喘的作用机理，为新的哮喘治疗药物的寻找提供新的思路。