Yang Yifei, Chi Liang, Hsiao Yun-Chung, Lu Kun
Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill, NC, 27599, United States.
bioRxiv. 2024 Jun 27:2024.06.27.601003. doi: 10.1101/2024.06.27.601003.
Gut microbiome is a group of microorganisms that plays important roles in contributing to health and diseases. These bacterial compositions have been demonstrated to impact bile acids (BAs) profiles, either by directly metabolizing primary BAs to secondary BAs or indirect ways through host metabolism by influencing BAs synthesis, transportation and conjugation in liver. It has been observed sexually dimorphic gut microbiome and bile acids composition, with variations in expression levels of bile acid metabolizing genes in the liver. However, associations between sex-specific differences in gut microbiome and BAs profiles are not well understood. This study aimed to investigate whether gut microbiome could influence BAs profiles in host in a sexspecific manner. We transplanted cecum feces of male and female C57BL/6 mice to male mice and measured BAs concentrations in feces, serum and liver samples 7 days after fecal transplantation. We found different BAs profiles between mice with male and female gut microbiome, including altering levels and proportions of secondary BAs. We also observed varied expression levels of genes related to bile acid metabolism in the liver and distal ileum. Our results highlight sex-specific effects of gut microbiome on shaping bile acid metabolism through gut bacteria and regulation of host genes.
肠道微生物群是一组在促进健康和引发疾病方面发挥重要作用的微生物。这些细菌组成已被证明会影响胆汁酸（BAs）谱，其方式要么是将初级胆汁酸直接代谢为次级胆汁酸，要么是通过影响肝脏中胆汁酸的合成、运输和结合，以间接方式通过宿主代谢来实现。已经观察到肠道微生物群和胆汁酸组成存在性别差异，肝脏中胆汁酸代谢基因的表达水平也有所不同。然而，肠道微生物群的性别特异性差异与胆汁酸谱之间的关联尚未得到充分理解。本研究旨在调查肠道微生物群是否能够以性别特异性方式影响宿主中的胆汁酸谱。我们将雄性和雌性C57BL/6小鼠的盲肠粪便移植到雄性小鼠体内，并在粪便移植7天后测量粪便、血清和肝脏样本中的胆汁酸浓度。我们发现具有雄性和雌性肠道微生物群的小鼠之间存在不同的胆汁酸谱，包括次级胆汁酸水平和比例的改变。我们还观察到肝脏和回肠末端中与胆汁酸代谢相关基因的表达水平有所不同。我们的结果突出了肠道微生物群通过肠道细菌和宿主基因调控对塑造胆汁酸代谢的性别特异性影响。
