Brain, antibiotics, and microbiota - how do they interplay?: An Editorial for 'Antibiotics-induced modulation of large intestinal microbiota altered aromatic amino acid profile and expression of neurotransmitters in the hypothalamus of piglets' on page 219.

The microbiome and its cross-talk with the brain have drawn increasing attention lately, since imbalances in the gut microbiota's composition may result in pathogenic dysfunctions affecting brain functioning up to development of neurodegenerative and mental diseases. The current Editorial discusses a study by Gao and coworkers in the current issue of the Journal of Neurochemistry in which the authors use a model of antibiotic-induced dysbiosis - targeted infusion of antibiotics into the gut - to assess if microbiotic metabolites exert effects on local neurotransmitter expression or contribute to the gut-brain axis. The authors mechanistically link distal ileal infusion of antibiotics with a change in the levels of microbial metabolites that affect the expression of neurotransmitters in the brain and thereby can participate in the fine-tuning of the hypothalamic functions, including regulation of visceral and neuroendocrine processes, stress responses, mood and anxiety. Their study thus represents an important step towards our understanding of the brain-gut axis, with the potential to advance therapeutics.