文献类型： 外文期刊

作者： Xia, Rui ¹ ; Zhang, Qingshuang ¹ ; Xia, Dongmei ¹ ; Hao, Qiang ¹ ; Ding, Qianwen ¹ ; Ran, Chao ³ ; Yang, Yalin ³ ; Cao, Aizhi ⁴ ; Zhang, Zhen ³ ; Zhou, Zhigang ¹ ;

作者机构： 1.Chinese Acad Agr Sci, Inst Feed Res, China Norway Joint Lab Fish Gut Microbiota, Beijing 100081, Peoples R China

2.Norwegian Univ Sci & Technol, Inst Biol, Norway China Joint Lab Fish Gut Microbiota, Trondheim, Norway

3.Chinese Acad Agr Sci, Inst Feed Res, Minist Agr & Rural Affairs, Key Lab Feed Biotechnol, Beijing 100081, Peoples R China

4.Shandong Longchang Anim Hlth Care Co Ltd, Jinan 251100, Peoples R China

5.Jiangxi Acad Agr Sci, Inst Anim Husb & Vet, Nanchang 330000, Jiangxi, Peoples R China

关键词： Bile acids; Gut barrier; Gut microbiota; Largemouth bass; Germ -free zebra fish

期刊名称：ANIMAL NUTRITION （ 影响因子：6.3； 五年影响因子：6.9 ）

ISSN： 2405-6383

年卷期： 2023 年 14 卷

页码：

收录情况： SCI

摘要： Fish gut barrier damage under intensive culture model is a significant concern for aquaculture industry. This study aimed to investigate the effects of bile acids (BAs) on gut barriers in Micropterus salmoides. A germ-free (GF) zebrafish model was employed to elucidate the effects of the direct stimulation of BAs and the indirect regulations mediated by the gut microbiota on gut barrier functions. Four diets were formulated with BAs supplemented at 0, 150, 300 and 450 mg/kg, and these 4 diets were defined as control, BA150, BA300 and BA450, respectively. After 5 weeks of feeding experiment, the survival rate of fish fed with BA300 diet was increased (P < 0.05). Histological analysis revealed an improvement of gut structural integrity in the BA150 and BA300 groups. Compared with the control group, the expression of genes related to chemical barrier (mucin, lysozyme and complement 1) and physical barrier (occludin and claudin-4) was increased in the BA150 and BA300 groups (P < 0.05), and the expression of genes related to immunological barrier (interleukin [IL]-6, tumor growth factor b, IL-10, macrophage galactose -type lectin and immunoglobulin M [IgM]) was significantly increased in the BA300 group (P < 0.05), but the expression of genes related to chemical barrier (hepcidin) and immunological barrier (IL-1b, tumor necrosis factor -a, IL-6 and arginase) was significantly decreased in the BA450 group (P < 0.05). Gut microbiota composition analysis revealed that the abundance of Firmicutes was augmented prominently in the BA150 and BA300 groups (P < 0.05), while that of Actinobacteriota and Proteobacteria showed a downward trend in the BA150 and BA300 groups (P > 0.05). The results of the gut microbiota transferring experiment demonstrated an upregulation of gut barrier-related genes, including immunoglobulin Z/T (IgZ/T), IL-6, IL-1b and IL-10, by the gut microbiota transferred from the BA300 group compared with the control (P < 0.05). Feeding the BA300 diet directly to GF zebrafish resulted in enhanced expression of IgM, IgZ/T, lysozyme, occludin-2, IL-6 and IL-10 (P < 0.05). In conclusion, BAs can improve the gut barriers of fish through both direct and indirect effects mediated by the gut microbiota. (c) 2023 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).