miRNA146/155表达上调在电针治疗脓毒症中的作用机制研究

Sepsis is the leading cause of death in the patients of noncoronary intensive care unit patients. Although avariety of progress have been made in understanding of the pathogenesis of sepsis and improvement of clinical therapeutic means, the mortality remains as high as 18-50%, of which one of the main reason is because of the lack of effective systemic immunomodulatory therapy. Recently, we reported that electro-acupuncture treatment plays an effective and reliable role in protecting brain from ischaemia and re-perfusion injury. In recent five years, a few of groups also reported that electro-acupuncture treatment can decrease mortality of sepsis and protect the multiple organs of sepsis rats. The mechanism of electro-acupuncture protection role in inflammatory diseases is believed to be closely related with the cholinergic anti-inflammatory pathway activation. However, all the exsited studies about the mechanism were only stopped at the cell and protein levels. In these studies only the cytokine and immune function changes were observed. The more in-depth machanism is far from clarified. Recent studies suggested that miRNA146/155 negtive feedback modulation after transcription is the key machanism of inflammation. But there were no further studies about the role of miRNA146/155 in the electro-acupuncture treatment of septis and the cholinergic anti-inflammatory pathway. In this project, the role of miRNA146/155 up-regulation in a negtive feedback way in the electro-acupuncture treatment of septis and the cholinergic anti-inflammatory pathway will be studied. The aim of this project is to clarify the in-depth molecular machanism of the electro-acupuncture treatment in sepsis therapy and the central modulation mechanism of cholinergic anti-inflammatory pathway. This project will be expected to provide a new theoretical basis and a new therapy target in sepsis. So, it has important theoretical significance and clinical value.

脓毒症是ICU住院病人首要致死原因，尽管对脓毒症的研究已取得一定进展，但是由于整体免疫调节治疗手段的缺乏，其死亡率仍高达18-50%。近五年来，我们及国内外同行发现，电针在脓毒症治疗及脑缺血损伤防护方面有可靠疗效，其机制与胆碱能抗炎通路激活密切相关，但是已有的机制研究仅停留于细胞及蛋白水平，更深入的机制远未阐明。新近的研究提示，miRNA146/155在转录后水平负反馈调节是免疫炎症反应的关键机制，而其在电针治疗及胆碱能抗炎通路中的作用研究却尚属空白。本课题拟通过活体和离体脓毒症模型，利用分子生物学、免疫学和细胞生物学等手段，深入研究miRNA146/155负反馈调节增强在电针治疗脓毒症中的作用以及在胆碱能抗炎通路中的作用，旨在阐明电针治疗脓毒症的转录后水平调节机制和胆碱能抗炎通路的中枢调节机制，为临床脓毒症的防治提供新的理论根据和新的作用靶点，具有重要的理论意义和临床应用价值。

脓毒症是ICU住院病人首要致死原因，尽管对脓毒症的研究已取得一定进展，但是由于整体免疫调节治疗手段的缺乏，其死亡率仍高达18-50%。高死亡率主要跟脓毒症引起的难控制性的全身炎症反应，并最终发展成多器官功能衰竭相关。近年来，我们及国内外同行发现，电针在脓毒症治疗及脑缺血损伤防护方面有可靠疗效，其机制与胆碱能抗炎通路激活密切相关，而其在电针治疗及胆碱能抗炎通路中的作用研究却尚属空白。胆碱能抗炎通路是近十年来对迷走神经功能研究的一项新的发现。该通路通过调节机体自主神经系统控制系统免疫，展现出其临床应用于治疗脓毒症类过度免疫炎症反应性疾病方面的巨大潜力。因此，本课题旨在探索电针是否通过巨噬细胞a7nAchR介导的胆碱能通路对脓毒症小鼠发挥器官保护和抗炎作用及其机制。. 本课题包含两部分：第一部分为药物激活a7nAchR介导的胆碱能通路在离体脓毒症中发挥保护效应的实验研究；第二部分：电针激活a7nAchR介导的胆碱能通路在在体脓毒症中发挥保护效应的实验研究。. 研究表明， LPS诱导RAW264.7细胞促性因子TNF-α表达上调，在24小时达高峰；a7nAchR激动剂GTS-21剂量依赖性地降低了LPS诱导的促炎因子表达水平，同时降低了LPS诱导的HMGB1的表达水平, 并反转了LPS诱导的HMGB1胞质转移，且逆转了LPS诱导的NF-κB p65的核转位。因此得出结论，a7nAchR激动剂通过抑制NF-κB的活化减轻LPS诱导巨噬细胞炎性反应。电针通过激活a7nAchR介导的胆碱能通路减轻脓毒症小鼠脏器损伤和全身炎症反应，表现为电针改善了脓毒症小鼠的肺组织病理损伤程度，减小了肺湿干重比值，降低了支气管肺泡灌洗蛋白浓度，减轻了肝脏巨噬细胞和嗜中性粒细胞的浸润和降低了腹腔灌洗液中促炎因子的水平，是通过减轻脓毒症小鼠肺脏中NF-κB的活性发挥效应的。. 胆碱能抗炎通路的药物激活以及电针激活发挥器官保护和减轻全身炎症反应效应为预防性的减小ICU高危人群的脓毒症发病率提供了理论依据,为临床脓毒症的防治提供新的理论依据和新的作用靶点，具有重要的理论意义和临床应用价值。