针刺调控肠道菌群-宿主代谢免疫交互的Th17/Treg平衡机制研究

Our previous NSFC subject showed that acupuncture can regulate the metabolic interaction between gut microbiota and host, which provide new evidence for explaining the holistic role of acupuncture from the view of "microbiota-host interaction". However, the potential meaning and mechanism of such role are not be clarified. The latest reseaches show co-metabolites produced by microbiota and host can remodel T cells and mainly reflects in the balance of Th17/Treg immune axis，which is crucial for metabolic immune interaction of microbiota and host. In addition, studies also find that HIF1α, the common integrator of metabolic cues, can regulate Th17/Treg immune axis through RORγt and FOXP3 related signal pathway.These findings provide us new strategy to study how acupuncture influence the crosstalk between microbiota and host. In this subject, we assume that acupuncture can regulate the metabolic immune interaction of microbiota-host, which is mainly resulted by Th17/Treg immune axis balance. To prove that, we will take ulcerative colitis (UC) as research object, employ gene knockout mice and combine macro-methods (such as molecular ecological methods, LC/MS metabonomics methods) and micro-methods (such as flow cytometry and qRT-PCR techniques) to study whether acupuncture with Zusanli and Guanyuan can regulate the microbiota-host metabolic immune interaction of UC, whether this effect is controled by Th17/Treg balance, and whether this balance is closely related to HIF1α-RORγt/FOXP3 pathway. The results will give more scientific evidence for explaining the holistic role of acupuncture from the perspective of "microbiota-host interaction" .

菌群-宿主交互平衡是维持人体健康的先决条件，也为研究针灸整体调整作用提供了新思路。已完成的国家自然科学基金表明，针刺对肠道菌群－宿主的代谢交互具有调控作用，但机制未明。最新突破性进展表明，菌群与宿主交互的重要内涵在于代谢免疫交互，HIF1α-RORγt/FOXP3通路介导的Th17/Treg平衡是菌群与宿主代谢免疫交互的关键环节。本研究拟紧密围绕"针刺通过Th17/Treg平衡调控菌群-宿主代谢免疫交互"的假说，以溃疡性结肠炎为研究载体，予以针刺"足三里、关元"，整合运用分子生态学、代谢组学等宏观研究方法探明针刺对菌群-宿主代谢免疫交互的调控效应；引入基因敲除小鼠动物模型，运用流式细胞术、qRT-PCR等微观技术手段揭示针刺通过HIF1α-RORγt/FOXP3介导的Th17/Treg平衡调控菌群-宿主代谢免疫交互的机制，以进一步从"菌群-宿主交互"的角度丰富针灸整体调整作用的科学内涵。

宿主与肠道菌群的交互作用和平衡是维持人体健康的重要条件，我们在长期的研究中发现，针刺作用并非只发挥或体现在宿主层面，“菌群与宿主交互”在针刺调节效应中的作用不容忽视，基于此，本课题以DSS诱导的溃疡性结肠炎模型为载体，分别从针灸的治疗效应、针灸对肠道菌群－宿主代谢免疫交互的调整作用、针灸对菌群－宿主代谢免疫交互的关键靶点Th17/Treg免疫轴的调整作用、针灸对Th17/Treg平衡的关键信号通路HIF1α-RORγt/ FOXP3的影响以及“肠道菌群多样性-代谢小分子变化-Th17/Treg免疫轴稳态”相关性等方面进行了研究。研究结果明确了针灸治疗可以显著改善DSS诱导的UC模型各种症状及病理变化，提高小鼠肠道菌群ace、chao和sobs等多样性指数，特别是提高了乳杆菌属、毛螺旋菌科等核心菌群的丰度，降低了Odoribacter、Allobaculum等菌群的丰度，同时有效改善了失衡的Th17/Treg免疫平衡轴，对血浆中IL-23,TGF-b,IL-6, IL-12, IL-10,IL-17,IL-2, IL-4, IL-21等多种细胞因子均有调整作用，对Treg上游核心调控蛋白FOXP3及Th17核心调控蛋白RORγt/的表达也有显著的改善作用，并明确该作用与调节HIF-1ɑ表达有关。其次，采用代谢组学技术明确了针刺可改善UC动物血浆中紊乱的甘油二酯、丁酸、丁酰胆碱酯酶、丙酸、肉碱等小分子代谢物，其代谢通路可能涉及药物代谢酶、胆汁分泌、甘油磷脂代谢、胆碱代谢、嘌呤代谢等多条途径。相关分析显示Th17与肠道菌群多样性呈负相关，Treg与肠道菌群多样性呈显著正相关。甘油二酯、丁酰胆碱酯酶、肉碱等小分子代谢物与Th17/Treg免疫轴也有一定相关性。从而多角度揭示了针灸通过HIF1α-RORγt/FOXP3信号通路介导的Th17/Treg平衡调控“菌群-宿主代谢免疫交互”的作用机制，为针刺通过改善宿主-菌群代谢免疫交互提供了新的科学依据，相关成果为针灸治疗胃肠道疾病的机制研究提供了有益借鉴。目前发表论文20篇，其中SCI收录3篇，全面完成了研究任务。