Mechanisms, Phenotypes, and Translational Applications of the Gut-Brain Axis in Neurological Function Regulation

The gut microbiota functions as an endocrine-like system that engages in two-way communication with the brain through the gut-brain axis (GBA). It consists of largely endocrine, some neural but also immunological pathways. Data have begun to speculate that dysbiosis may result in behavioral abnormalities, including depression and anxiety the pathological basis of which may be based on neuroinflammation and derivatives of impaired synaptic plasticity and that it may accelerate neurodegenerative disease like Alzheimer’s disease (AD). Dysbiosis, by operating on certain molecular pathways closely linked to factors, and other mechanisms, empowers the gut microbiome as a potential biomarker for neurological disease with potential for manipulation of the microbiota - probiotics, dietary modulation and FMT, as disease prevention and therapy. Current studies are challenged by a lack of discerning causality. Future studies must now translate basic findings to patients through trans-disciplinary collaboration to define targeted manipulation of the gut microbiota to promote brain health.