Data_Sheet_1_Dietary Bile Salt Types Influence the Composition of Biliary Bile Acids and Gut Microbiota in Grass Carp.PDF

Lipid metabolism can influence host’s health. There is increasing evidence for interplay between two key regulating factors in lipid metabolism: bile acids (BAs) and gut microbiota. However, very little is known about how types of different diet-supplemented bile salts (BS) influence this interaction in vivo. We sought to explore these relationships using grass carp (Ctenopharyngodon idellus), which often suffers functional disorder of liver and gallbladder. We studied fluctuations of BAs in the gall and changes of microbial communities in the gut in response to seven different diets: five different BS, chelating BS agent, and control. The BS comprised two primary BS [sodium taurochololate (TCAS) and sodium taurochenodeoxycholate (TCDCAS)], sodium tauroursodeoxycholate (TUDCAS), and two secondary BS [sodium taurodeoxycholate (TDCAS) and sodium taurolithocholate (TLCAS)]. Supplementation of primary BS caused a more significant fluctuation of biliary BAs than secondary BS, and TCAS caused a more prominent increase than TCDCAS and TUDCAS. For the gut microbiota, primary BS tended to increase their diversity and induce community succession, secondary BS resulted in a higher firmicutes/bacteroidetes ratio, while TUDCAS had no significant effects. Changes of the gut microbiota triggered by different types of BS caused alteration in BAs biotransformation. Two-obesity-associated families, Lachnospiraceae and Ruminococcaceae were positively correlated with biliary cholic acid (CA), taurochenodeoxycholic acid (TCDCA), and deoxycholic acid (DCA). As both primary and secondary BS resulted in increased synthesis of toxic secondary Bas by the gut microbiota, future studies should pay closer attention to gut microbiota when considering BA treatment.

脂质代谢对宿主健康具有显著影响。日益增多的证据表明，在脂质代谢中，两种关键的调节因素——胆汁酸（BAs）和肠道微生物群——之间存在相互作用。然而，关于不同类型饮食补充的胆盐（BS）如何影响这种体内相互作用的研究却鲜为人知。本研究旨在利用草鱼（Ctenopharyngodon idellus）这一常患肝胆功能紊乱的物种，探究这些关系。我们研究了在七种不同饮食（包括五种不同的BS、螯合BS剂和对照组）下，胆囊中胆汁酸的变化以及肠道微生物群的改变。这些BS包括两种主要胆汁酸[钠牛磺胆酸（TCAS）和钠牛磺鹅脱氧胆酸（TCDCAS）]、钠牛磺鹅脱氧胆酸（TUDCAS）以及两种次级胆汁酸[钠脱氧胆酸（TDCAS）和钠牛磺石胆酸（TLCAS）]。主要BS的补充比次级BS更能显著影响胆汁酸的波动，其中TCAS比TCDCAS和TUDCAS引起更显著的升高。对于肠道微生物群，主要BS倾向于增加其多样性并诱导群落演替，而次级BS则导致厚壁菌门与拟杆菌门的比例升高，而TUDCAS则没有显著影响。不同类型BS引起的肠道微生物群的变化引发了胆汁酸生物转化的变化。与肥胖相关的两个家族，即Lachnospiraceae和Ruminococcaceae，与胆汁酸（CA）、鹅脱氧胆酸（TCDCA）和脱氧胆酸（DCA）呈正相关。鉴于主要和次级BS均导致肠道微生物群产生有毒的次级胆汁酸，未来的研究在考虑胆汁酸治疗时，应更加关注肠道微生物群。