Insulin/PI3K/Akt信号通路对高能低蛋白日粮致蛋鸡脂肪肝出血综合征形成机制研究

Fatty liver hemorrhagic syndrome (FLHS) is a nutritional and metabolic disease characterized by excessive fat in the liver of prolific laying hens, associated with varying degrees of hemorrhage and reduction of egg production. A surfeit of energy, such as excessive fat or carbohydrates in the diets is the main cause of fatty liver hemorrhagic syndrome in laying hens, but its pathogenesis is not well understood. Accumulating evidences indicate that deregulation of the phosphatidylinositol 3-kinase (PI3K)/AKT pathway is a common molecular event associated with metabolic dysfunctions including obesity, metabolic syndrome, and the NAFLD. Therefore, this study establishes a model of fatty liver hemorrhagic syndrome by high-energy low-protein diet, and to reveal the relationships between Insulin/PI3K/Akt signaling pathways and FLHS in vitro and in vivo, and to explore the exact regulatory mechanism of Insulin/PI3K/AKT signaling pathway to prevent and control FLHS by lipotropism-factors. The value and novelty of this study is to elucidate the pathogenesis and prevention mechanism of FLHS by novel evidence of insulin and its signaling pathway on the molecular level. Moreover, this study also provides reference for insulin resistant related diseases of humans in Comparative Medicine.

蛋鸡脂肪肝出血综合征(FLHS)是蛋鸡体内脂肪代谢紊乱引起的以肝脏发生脂肪病变、出血、产蛋率下降为主要特征的营养代谢疾病，是高产蛋鸡常见多发病。高能、高脂等营养因素仍是蛋鸡生产中诱发蛋鸡脂肪肝出血综合征主要病因，但其发病机制尚不清楚。越来越多研究表明，Insulin/PI3K/Akt信号通路紊乱是人类多种代谢疾病（肥胖、非酒精性脂肪肝、代谢综合征）发病的分子机制。本研究采用高能低蛋白日粮建立蛋鸡脂肪肝出血综合征模型，并通过动物临床实验和体外实验，研究Insulin/PI3K/Akt信号通路与FLHS关系，探讨Insulin/PI3K/Akt信号通路对蛋鸡脂肪肝出血综合征作用机制以及抗脂因子的干扰机制；为蛋鸡脂肪肝出血综合征发病机理的研究提供新的分子生物学依据，并从比较医学上，对人类胰岛素抵抗相关疾病研究提供参考。

蛋鸡脂肪肝出血综合征（FLHS）是当前蛋鸡养殖过程中常见病，其发病率呈逐年升高趋势；然而目前对于该病的发病机制尚不清楚；本课题针对“Insulin/PI3K/Akt信号通路是参与FLHS形成的关键信号通路”这一科学假设进行科学验证。主要研究内容为：1）采用高能低蛋白日粮诱发FLHS，采用RNA-seq，代谢组学、Real-time PCR、透射电镜技术及临床病理学等方法，分析蛋鸡在FLHS发病过程中胰岛素抵抗、insulin/PI3K/Akt信号通路及其主效基因的变化；以此探究insulin/PI3K/Akt信号通路与FLHS形成机制的关系。2）通过抗脂因子（白藜芦醇，RSV）对高能低蛋白日粮诱发FLHS的调控作用机制，分析RSV对FLHS蛋鸡胰岛素抵抗、Insulin/PI3K/Akt信号通路及脂类代谢等相关指标的影响。3）利用原位二步灌流法分离培养肝细胞，构建肝脂病变模型，并利用抑制剂对肝脂模型进行干预，检测肝脏脂肪代谢基因与Insulin/PI3K/Akt信号通路的变化，从体外研究分析Insulin/PI3K/Akt信号通路对肝脏脂肪沉积的影响。本项目试图从体内外研究揭示Insulin/PI3K/Akt信号通路对蛋鸡脂肪肝出血综合征的作用机制，并从比较医学上为人类胰岛素抵抗相关疾病提供参考。