New frontiers for host-microbe interactions continue to emerge as our knowledge of the adult gut microbiome in health and disease is continually supplemented and improved. Alterations in the gut microbiota composition in irritable bowel syndrome (IBS) are now linked to symptom severity while population-based evidence linking gut microbiome signatures to depression is an important new landmark. The effects of drugs on gut microbiome composition are also becoming clearer. Meanwhile, preclinical studies have delineated the influence of the gut microbiome at a structural and activity level in distinct brain regions. Bacterial metabolites, such as tryptamine, can activate specific receptors to impact gastrointestinal motility. These recent studies bring into focus the future implications for therapeutic targeting of the microbiome–gut–brain axis.

随着我们对成年肠道微生物组在健康和疾病方面的知识的不断补充和改进，宿主-微生物相互作用的新领域不断涌现。肠易激综合症（IBS）中肠道菌群组成的改变现在与症状严重程度相关，而将肠道微生物组特征与抑郁症联系起来的基于人群的证据是一个重要的新里程碑。药物对肠道微生物组组成的影响也越来越明显。同时，临床前研究已经在不同的大脑区域在结构和活性水平上描述了肠道微生物组的影响。细菌代谢产物（例如色胺）可以激活特定的受体，从而影响胃肠蠕动。这些最近的研究使微生物群-肠-脑轴靶向治疗的未来意义成为焦点。