马奶中的microRNA对人体免疫系统的作用机制研究

The mare's milk is high nutritional health drink exhibiting strong ethnic characteristics in the Mongolian prairie. By practice, horse milk can improve human immunity and prevent from diseases. However, there is lack of scientific evidence on interaction mechanism with human body, which affect the development of the productivity and marketability of the mare's milk. Recently, microRNAs （miRNAs）which is a new tool for the study of physiological and pathological mechanism, have been identified from many body fluids, including serum and milk, may serve as a critical biomarker for various diseases. In the present study, we extend our previous work on miRNAs in mare's milk and based on miRNAs to verify the potential mechanism of mare's milk on human immunity system. Firstly, the Solexa sequencing and qRT-PCR technology is employed to identify expression profiles of miRNAs in mare's milk. Secondly, functionally select the mare's milk-specific miRNAs in macrophage and C57BL/6 mice (including test of cytokine、migration、phagotrophy,etc). Thirdly, we perform bioinformatic analysis to forcast any sequences in the human, mouse, or rat genome with perfect or near-perfect match to the representative miRNAs, and verify by western blotting, luciferase assays. Finally, to the preliminary understanding of the metabolism of mare's milk in the human body, an expression level of serum miRNAs will be detected by qRT-PCR analysis. This study is critical to elaborate the importance of mare's milk in biological function, and also will lay theoretical foundation for functional evaluation and development of nutritional health products from mare's milk.

马奶是一种营养价值很高的具有浓厚民族特色的草原保健饮品。实践证明，马奶能够提高人体免疫力以及防治疾病。但缺乏作用机制方面的科学依据，影响了马奶的产业化及市场化。最近，研究生物体生理、病理机制的一种新工具-microRNA（miRNA）在血清、乳汁等体液中被发现，作为生物指标在疾病发病机理等研究中起非常重要的作用。本研究是以miRNA作为切入点，证明马奶对人体免疫系统中的作用机制。首先利用Solexa测序以及qRT-PCR技术鉴定马奶中存在的miRNA表达特征，然后在巨噬细胞和C57BL/6小鼠中进行对马奶特异性miRNA进行功能（细胞因子分泌、迁移、吞噬功能）筛选。接着利用生物信息学对代表性miRNA的靶基因进行预测并进行实验验证。最后通过检测miRNA在人血清中的表达量初步了解马奶在人体内的代谢。本研究对阐明马奶的生物学功能有重要的意义，为马奶营养保健品的功能评价与开发奠定科学理论基础。

马奶作为蒙医学饮食疗法之最常用于老弱病残或术后疗养人群，起保健作用，但是至今缺乏科学依据。本研究以马奶中的miRNA作为研究对象，探索马奶中的miRNA提高机体免疫力的作用和机理。首先，通过整理文献发现，当马奶、牛奶与人奶相比较时，马奶中的营养成分和药用成分与人奶非常相似；同时介于miRNA研究技术在现代医学上的广泛应用分析miRNA靶向作用技术在蒙药药理研究中的应用可能性，为蒙药作用机制研究引入关键技术储备促进蒙医药的发展。其次，利用Solexa测序以及qRT-PCR技术鉴定了马奶中特异性表达的miRNAs，并用巨噬细胞珠RAW264.7在体外实验中初步验证了这些miRNAs与机体免疫相关。最后，对过敏性鼻炎人患者和正常大鼠中进行马奶的服用，拟确定血液中的miRNAs与细胞因子、外周血T细胞亚细胞群的作用关系，此部分实验仍在进行中。本研究的成果以学术论文的形式输出，共发表了学术论文5篇，其中SCI收录论文2篇；1篇论文获全国学会学术论文奖；拟投稿论文两篇。本研究是一项引用miRNA研究技术从免疫学角度阐明马奶生物学功能的新颖研究，在马奶研究甚至蒙药研究领域占国内领先地位。此次研究不但为马奶营养保健品开发提供理论依据，也为马奶疗法的推广及临床治疗提供实验依据。后续研究中可挖掘更多其与他功能相关的miRNA用于马奶质控或作用靶标研究，为蒙药研究提供参考价值。