针刺减肥的STAT5-miR-193b信号通路中枢调控及机制研究

Aacupuncture is becoming widely used therapy for obese patients. As one of the key mechanisms of acupuncture for obesity, regulation in CNS has been well studied. However, by what molecular mechanisms the regulation occurs and what genes contribute to the regulation and how the gene expression is changed by acupuncture treatment are unknown yet. Based on our previous research, we propose that "STAT5 is a key molecule for obesity and plays a role in acupuncture treatment; as a potential target of STAT5 in CNS, miR-193b regulates genes that participate in food intake and fat metabolism". To examine this hypothesis, we imported Stat5 and miR-193b neural conditional knockout mice from NIH and employ new technologies, such as RNA-seq, ChIP-seq and other molecular biological techniques. The roles of STAT5 and miR-193b in obesity and acupuncture-induced anti-obesity will be examined and their regulatory relationship of these two molecules will be included in by this study. This study will provide scientific evidences at molecular and epigenetic regulation level by which acupuncture treatment is an effective therapeutic approach for obese patients.

中枢调控是针灸减肥作用机理的重点关注领域，从具体的分子靶点深入并明确其分子机理，在针灸减肥中将是今后研究的重要方向。基于本课题组在针刺减肥和细胞内信号传导通路的研究成果，紧密跟踪前沿的理论和技术，提出了"STAT5是肥胖的中枢关键因子并为针刺减肥的重要环节；其作用通过干扰miR-193b而实现对摄食中枢和脂肪代谢的影响，从而达到减肥效应"的新假说。围绕这一假说，拟通过运用课题申请者从美国NIH引进的Stat5中枢特异性基因敲除小鼠和最新建立的miR-193b中枢特异性基因敲除小鼠，利用前沿的RNA-seq、ChIP-seq及其他分子生物学、神经生物学技术，证实STAT5在针刺减肥中枢调控的关键作用，并从STAT5和miR-193b等表观遗传学调控的角度深入揭示其参与调控的机制，以期为针刺减肥中枢调控原理提供全新的阐释，并为针刺减肥的临床运用提供科学的实验数据。

本课题首次将中枢条件性敲除Stat5肥胖模型引入针刺减肥的实验研究中，以探讨针刺减肥的中枢调控机制。在明确针刺通过减少体重和体脂比，减少脂肪细胞体积，改善异常血脂代谢，促进小鼠抗寒能力等方面达到减肥效应之后，运用高通量的RNA-seq测序技术检测了中枢下丘脑和外周附睾脂肪的全基因表达谱，发现Stat5缺失后大量基因的表达上调导致肥胖，其中80%以上皆是属于代谢相关信号通路，如：PPAR脂肪细胞分化及形成,酪氨酸代谢，胰岛素信号通路，甘油三酯代谢，磷酸甘油酯代谢等等，而针刺可以将多数这些异常表达的基因回调至正常水平；并深入探讨了针刺减肥的中枢新靶点IGF1在肥胖发生的作用；同时，还深入探讨了miRNA-193b在中枢和外周调节作用的不同，具体表现为：Stat5敲除以后，下丘脑的miR-193b及下游相关靶基因Ucp1，Adpn水平升高，而针刺可以将其回调至正常水平；而外周脂肪却呈现相反的调节趋势。总之，课题组揭示了STAT5在肥胖的发生以及针刺减肥中枢调控中的作用，深入揭示STAT5的作用至少部分是通过调节miR-193b基因的表达从而调节肥胖相关基因的表达，为针刺减肥作用机理的诠释提供新的实验证据，而且借助于该课题成功建立了高通量测序平台。