Song Tingting, Liang Xiaofang, Wang Hao, Xue Min, Wang Jie
National Aquafeed Safety Assessment Center, Institute of Feed Research, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
Anim Nutr. 2024 Mar 30;17:87-99. doi: 10.1016/j.aninu.2024.03.008. eCollection 2024 Jun.
The prevalent practice of substituting fishmeal with plant protein frequently leads to disturbances in bile acid metabolism, subsequently increasing the incidence of metabolic liver diseases. Bile acid nutrients such as cholesterol, taurine and glycine have been shown to enhance bile acid synthesis and confer beneficial effects on growth. Therefore, this study aimed to investigate the effects of cholesterol-taurine-glycine (Ch-Tau-Gly) supplement on bile acid metabolism and liver health in spotted seabass () fed a plant-based diet. Two isonitrogenous and isolipidic diets were formulated: (1) plant protein-based diet (PP); (2) PP supplemented 0.5% cholesterol, 0.5% taurine and 1.3% glycine (CTG). Each experimental diet was randomly fed to quadruplicate groups of 30 feed-trained spotted seabass in each tank. The results revealed that supplementing plant-based diet with Ch-Tau-Gly supplement led to an increase in carcass ratio (meat yield) in spotted seabass ( < 0.05), indirectly contributing positively to their growth. The dietary supplement effectively suppressed endogenous cholesterol synthesis in the liver, promoted the expression of bile acid synthesis enzyme synthesis, and simultaneously the expression of intestinal and its downstream genes, including and ( < 0.05). The reduction in and bile salt hydrolase (BSH) were observed in CTG group with concurrently increased conjugated chenodeoxycholic acid (CDCA) bile acids ( < 0.05), suggesting the enhancement of the hydrophilicity of the bile acid pool. In CTG group, fatty liver was alleviated with a corresponding increase in lipid metabolism, characterized by a downregulation of genes associated with lipogenesis and lipid droplet deposition, along with an upregulation of genes related to lipolysis. Our study underscored the ability of Ch-Tau-Gly supplement to influence the gut microbiota, leading to an increase in the levels of conjugated CDCA ( < 0.05) in the bile acid pool of spotted seabass. The interplay between the gut microbiota and bile acids might constitute a crucial pathway in the promotion of liver health. These findings offer a promising solution, suggesting that Ch-Tau-Gly supplement have the potential to promote the growth of aquatic species and livestock fed on plant-based diets while addressing issues related to metabolic fatty liver.
用植物蛋白替代鱼粉的普遍做法常常导致胆汁酸代谢紊乱，进而增加代谢性肝病的发病率。胆固醇、牛磺酸和甘氨酸等胆汁酸营养物质已被证明能增强胆汁酸合成并对生长产生有益影响。因此，本研究旨在探讨在以植物性饲料喂养的花鲈中添加胆固醇 - 牛磺酸 - 甘氨酸（Ch - Tau - Gly）对胆汁酸代谢和肝脏健康的影响。配制了两种等氮和等脂的饲料：（1）植物蛋白为基础的饲料（PP）；（2）添加了0.5%胆固醇、0.5%牛磺酸和1.3%甘氨酸的PP（CTG）。每种实验饲料随机投喂到每个水箱中每组30尾经饲料驯化的花鲈，共四组。结果显示，在植物性饲料中添加Ch - Tau - Gly能提高花鲈的胴体率（肉产量）（P < 0.05），间接对其生长产生积极影响。饲料添加剂有效抑制了肝脏中内源性胆固醇的合成，促进了胆汁酸合成酶的表达，同时也促进了肠道FXR及其下游基因包括FGF15和SHP的表达（P < 0.05）。在CTG组中观察到CYP7A1和胆汁盐水解酶（BSH）减少，同时结合型鹅去氧胆酸（CDCA）胆汁酸增加（P < 0.05），这表明胆汁酸池的亲水性增强。在CTG组中，脂肪肝得到缓解，脂质代谢相应增加，其特征是与脂肪生成和脂滴沉积相关的基因下调，以及与脂肪分解相关的基因上调。我们的研究强调了Ch - Tau - Gly添加剂影响肠道微生物群的能力，导致花鲈胆汁酸池中结合型CDCA水平增加（P < 0.05）。肠道微生物群与胆汁酸之间的相互作用可能是促进肝脏健康的关键途径。这些发现提供了一个有前景的解决方案，表明Ch - Tau - Gly添加剂有潜力促进以植物性饲料喂养的水产养殖品种和家畜的生长，同时解决与代谢性脂肪肝相关的问题。
