Department of AgroBioChem/Precision Livestock and Nutrition Unit, AgroBioChem/TERRA, Gembloux Agro-Bio Tech, Liège University (ULiège), Gembloux, Belgium.
China-Norway Joint Lab on Fish Gastrointestinal Microbiota, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing China.
Gut Microbes. 2021 Jan-Dec;13(1):1-15. doi: 10.1080/19490976.2021.1900996.
The capability of carbohydrate utilization in fish is limited compared to mammals. It has scientific and practical significance to improve the ability of fish to use carbohydrates. The efficiency of dietary carbohydrate utilization varies among fish with different feeding habits, which are associated with differential intestinal microbiota. In this study, we found that zebrafish fed with omnivorous diet (OD) and herbivorous diet (HD) showed better glucose homeostasis compared with carnivorous diet (CD) fed counterpart and the differential glucose utilization efficiency was attributable to the intestinal microbiota. The commensal bacterium , an acetate producer, was enriched in OD and HD groups, and administration of in both adult zebrafish and gnotobiotic larval zebrafish models resulted in improved glucose homeostasis and increased insulin expression, supporting a causative role of enrichment in glucose homeostasis in fish. The enrichment of was constantly associated with higher acetate levels, and dietary supplementation of acetate promotes glucose utilization in zebrafish, suggesting a contribution of acetate in the function of . Furthermore, we found that the beneficial effect of both acetate and on glucose homeostasis was mediated through parasympathetic activation. Overall, this work highlights the existence of a -brain axis in the regulation of glucose homeostasis in fish and suggests a role of acetate in mediating the axis function. Our results suggest potential strategies for improvement of fish carbohydrate utilization.
与哺乳动物相比，鱼类利用碳水化合物的能力有限。提高鱼类利用碳水化合物的能力具有重要的科学和实际意义。不同摄食习性的鱼类对膳食碳水化合物的利用效率存在差异，这与肠道微生物群有关。在这项研究中，我们发现摄食杂食性和草食性饮食的斑马鱼比摄食肉食性饮食的斑马鱼具有更好的葡萄糖稳态，并且不同的葡萄糖利用效率归因于肠道微生物群。共生菌是一种乙酸产生菌，在杂食性和草食性饮食组中富集，在成年斑马鱼和无菌幼鱼模型中添加 可改善葡萄糖稳态并增加胰岛素表达，支持 丰度增加在鱼类葡萄糖稳态中的因果作用。 的富集与更高的乙酸水平始终相关，并且膳食中补充乙酸可促进斑马鱼利用葡萄糖，提示乙酸在 的功能中起作用。此外，我们发现乙酸和 对葡萄糖稳态的有益作用都是通过副交感神经激活介导的。总的来说，这项工作强调了鱼类葡萄糖稳态调节中存在的 -脑轴，并表明乙酸在介导轴功能中起作用。我们的研究结果为提高鱼类碳水化合物利用效率提供了潜在策略。
