Growing evidence implicates the gut microbiome in cognition. Blastocystis is a common gut single-cell eukaryote parasite frequently detected in humans but its potential involvement in human pathophysiology has been poorly characterized. Here we describe how the presence of Blastocystis in the gut microbiome was associated with deficits in executive function and altered gut bacterial composition in a discovery (n = 114) and replication cohorts (n = 942). We also found that Blastocystis was linked to bacterial functions related to aromatic amino acids metabolism and folate-mediated pyrimidine and one-carbon metabolism. Blastocystis-associated shifts in bacterial functionality translated into the circulating metabolome. Finally, we evaluated the effects of microbiota transplantation. Donor’s Blastocystis subtypes led to altered recipient’s mice cognitive function and prefrontal cortex gene expression. In summary, Blastocystis warrant further consideration as a novel actor in the gut microbiome-brain axis.

越来越多的证据表明肠道微生物组与认知有关。芽囊原虫是一种常见的肠道单细胞真核寄生虫，经常在人类中检测到，但其在人类病理生理学中的潜在参与尚未得到充分表征。在这里，我们描述了肠道微生物组中囊胚菌的存在如何与执行功能缺陷和肠道细菌组成的改变相关，发现 ( n  = 114) 和复制队列 ( n  = 942)。我们还发现Blastocystis与芳香族氨基酸代谢和叶酸介导的嘧啶和一碳代谢相关的细菌功能有关。胚泡属- 细菌功能的相关变化转化为循环代谢组。最后，我们评估了微生物群移植的效果。捐赠者的囊胚亚型导致接受者的小鼠认知功能和前额皮质基因表达发生改变。总之，囊胚作为肠道微生物组-脑轴中的一个新角色值得进一步考虑。