胆碱通过肠道菌群影响斑马鱼脂肪肝形成效应及机制

脂肪肝病是养殖鱼类常见营养性疾病，严重危害动物健康和品质。胆碱可促进肝内脂肪转变为磷脂而转运至肝外，防止脂肪沉积。饮食中胆碱水平影响宿主肠道菌群结构，而肠道菌群可调节宿主脂肪代谢。关于胆碱通过肠道菌群影响水产动物脂肪肝形成效应及机制未见报道。本项目以模式生物—斑马鱼为对象，通过控制饲料中胆碱水平诱导脂肪肝模型。基于16S rDNA 高通量测序对健康组与诱导组斑马鱼肠道微生物进行比较分析，挖掘差异微生物中与宿主脂代谢相关的菌群因子。利用无菌斑马鱼模型，开展健康组和诱导组斑马鱼肠道微生物移植试验，探究不同菌群对斑马鱼肝脂水平的影响，利用RNA-seq对肝脏测序，进行GO(Gene ontology)分析和KEGG通路富集，寻找微生物对宿主脂代谢相关基因以及信号通路。本研究的目的在于从“肠—肝轴”角度阐释胆碱影响水产动物脂肪肝形成效应及机制，为水产动物脂肪肝微生态防治奠定理论基础。

Fatty liver is a common nutritional disease in aquaculture which harming animal health and quality. Choline can prevent fatty liver through promoting fatty transmitssion as phospholipid from liver. Choline can effect the structure of gut microbiota which regulate host lipid metabolism. Study about the structure changes of gut microbiota effected by choline and its action on fatty liver in aquatic animal have not been reported. In this project, healthy and fatty liver zebrafish will be induced by diet control with or without choline supplementation. The structural changes of gut bacteria samples will be analyzed through high throughput sequencing and bioinformatics analysis. The core bacteria groups related to the lipid metabolism will be mined from the data. Then the gut bacteria from treatments dietary with or without choline supplementation will be transmit to the gnotobiotic fish for analyzing the effects on lipid level. High throughput analysis methods-RNA-seq was used to sequence the transcriptome level of liver. Gene ontology analysis (GO) and the KEGG database were used to look for lipid metabolism related genes and signaling pathways. This project is aimed to illuminate the mechanism of choline effect on fatty liver via gut-liver axle in fish which lay a foundation for microbial control of fatty liver in aquatic animal.