亚油酸通过NFκB-MCP1影响黄姑鱼脂肪组织巨噬细胞浸润机制的研究

The shortage of fish oil resources lead to the increase of soybean oil usage, which usually induce the pro-inflammatory response in fish species. Our primary data indicated that dietary soybean oil,whose main component is linoleic acid, induced pro-inflammatory response was closely related to macrophage infiltration in adipose tissue (AT), while the mechanism of macrophage infiltration into AT regulated by fatty acids was unclear in fish. This project intend to investigate the mechanism of dietary linoleic acid inducing macrophage infiltration by nuclear factor κB- monocyte chemotactic protein 1 (NFκB-MCP1) signaling pathway in vivo of yellow drum. In vitro, transwell migration experiment will be conducted to simulate the effects of AT cells to macrophage migration, combined with molecular biological techniques of gene knock-down and over-expression. In vitro experiment will further elucidate the MCP1 production mechanism, as well as the the role of MCP1 in macrophage migration. This project not only help to elucidate the mechanism of dietary fatty acid induced immune response in AT, but also provide theoretical basis to decrease dietary vegetable oil induced pro-inflammatory response, which will helps to save fish oil resources.

鱼油资源短缺导致饲料中豆油使用量增加，但饲料中高比例豆油往往造成鱼体炎症反应。申请人前期研究发现饲料中豆油（主要成分亚油酸）导致的鱼体炎症反应与脂肪组织巨噬细胞大量聚集（浸润）有关，但脂肪酸影响鱼类脂肪组织巨噬细胞浸润的机制尚不清楚。本项目以黄姑鱼为研究对象，在体实验研究饲料中亚油酸通过核因子κB（NFκB）信号通路调控单核细胞趋化蛋白1（MCP1）的表达进而影响黄姑鱼脂肪组织巨噬细胞浸润的分子机制；离体实验采用Transwell迁移技术，通过模拟在体条件下脂肪细胞对巨噬细胞迁移的影响，结合基因敲降和过表达等分子生物学技术，进一步研究亚油酸调控脂肪细胞MCP1表达的机制及MCP1在巨噬细胞迁移中的作用。该项目的实施不仅有助于阐释脂肪酸调控黄姑鱼脂肪组织炎症的机制，而且为缓解植物油替代鱼油引起的鱼类炎症反应提供理论基础，进而节约鱼油资源。

本研究首先通过体内和体外相结合的方法验证了豆油（亚油酸）诱导黄姑鱼脂肪组织巨噬细胞浸润的现象；其次，通过体外脂肪酸孵育和双荧光素酶实验，揭示亚油酸诱导MCP1的表达及其可能机制；最后，通过过表达和敲降MCP1建立MCP1表达与巨噬细胞迁移之间的联系，证实了MCP1在脂肪组织巨噬细胞浸润中的作用。本研究的实施证实了亚油酸诱导鱼类脂肪组织巨噬细胞浸润的现象，发现了NFkB信号通路对MCP1的调控机制，揭示了MCP1在脂肪组织巨噬细胞浸润中的作用，为阐释豆油替代鱼油导致的鱼类健康问题提供理论依据。