Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland.
APC Microbiome Ireland, University College Cork, Cork, Ireland.
Mod Trends Psychiatry. 2021;32:40-57. doi: 10.1159/000510416. Epub 2021 May 6.
The dynamic population of microbes that reside in the gastrointestinal tract plays a pivotal role in orchestrating several aspects of host physiology and health, including but not limited to nutrient extraction and metabolism, as well as the regulation of intestinal epithelial barrier integrity. Gut microbes interact with the host in a bi-directional manner as the microbiota can support the development and education of the innate and adaptive immune systems, thereby conferring protection against pathogens and harmful stimuli while training the host to maintain a homeostatic tolerance towards commensal symbiotics. Recent advances in the field have highlighted the importance of the host-microbiota relationship in neurodevelopment and behaviour, with relevant implications for the onset and progression of brain disorders of inflammatory origin. Microbial modulation of brain function is achieved throughout complex neuro-immune-endocrine pathways of the microbiome-gut-brain axis. Changes in the composition of the gut microbiota or perturbation in microbial-derived metabolites and neuroactive compounds are sensed by the afferent branches of the sympathetic and vagal innervation and transmitted to the central nervous system, which in turn produces behavioural responses. Here, we focus on how the crosstalk between the gut microbiota and the immune system modulates the development and function of the peripheral and central nervous systems. Specific attention is afforded to the involvement of host-microbe neuroimmune interactions in the pathogenesis of neuro-psychiatric and neuroinflammatory disorders such as autism spectrum disorders, anxiety, and depression, as well as Parkinson's and Alzheimer's diseases.
肠道中存在的微生物动态群体在调节宿主生理和健康的多个方面发挥着关键作用，包括但不限于营养物质的提取和代谢，以及肠道上皮屏障完整性的调节。肠道微生物以双向方式与宿主相互作用，因为微生物群可以支持先天和适应性免疫系统的发育和教育，从而为宿主提供对病原体和有害刺激的保护，同时训练宿主对共生共生体保持稳态耐受。该领域的最新进展强调了宿主-微生物群关系在神经发育和行为中的重要性，这对炎症性脑疾病的发病和进展具有相关影响。微生物对大脑功能的调节是通过微生物组-肠道-大脑轴的复杂神经免疫内分泌途径实现的。肠道微生物群组成的变化或微生物衍生的代谢物和神经活性化合物的扰动被交感和迷走神经支配的传入分支感知，并传递到中枢神经系统，中枢神经系统继而产生行为反应。在这里，我们重点关注肠道微生物群和免疫系统之间的相互作用如何调节外周和中枢神经系统的发育和功能。特别关注宿主-微生物神经免疫相互作用在神经精神和神经炎症性疾病（如自闭症谱系障碍、焦虑和抑郁以及帕金森病和阿尔茨海默病）发病机制中的参与。
