Psychobiotics: Evolution of novel antidepressants
Dinan, Timothy G.
Butler, Mary I.
Cryan, John F.
S. Karger AG, Basel
The gut-brain axis is a bidirectional communication system which allows the central nervous system and gastrointestinal tract to interact with and respond to each other rapidly and effectively. It is becoming increasingly clear that major players in this complex system are gut bacteria. The mechanisms of signal transmission from bacteria to the brain are complex and not fully elucidated, but include neural, endocrine, immune, and metabolic pathways. It was initially demonstrated in a rodent model of depression that the gut microbiota was altered. This observation has been replicated in patients with major depression who show decreased microbial diversity. Furthermore, when rodents receive a microbiota transplant from a depressed patient their behaviour alters, as does their tryptophan metabolism and immune status. Several studies of psychobiotics (bacteria with a potential mental health benefit) have been conducted in healthy populations and in patients with depression. While some psychobiotics have shown efficacy in treating depression, other bacteria have yielded negative findings. Larger-scale, well-designed studies are required. EU-funded guidelines recommend that patients with depression or vulnerability to depression should be encouraged to enhance a plant-based diet with a high content of grains/fibres, fermented foods, and fish. A significant impact of such a diet is likely mediated through the gut microbiota.
Gut-brain axis , Gut bacteria , Depression , Microbial diversity , Microbiota transplant , Psychobiotics
Dinan,T. G., Butler, M. I. and Cryan, J. F. (2021) 'Psychobiotics: Evolution of novel antidepressants', in Cowan C. S. M. and Leonard B. E. (eds): Microbes and the Mind. The Impact of the Microbiome on Mental Health, Modern Trends in Psychiatry, 32, pp. 134-143. doi: 10.1159/000510424
© 2021, S. Karger AG, Basel. This is the accepted manuscript version of an article published by S. Karger AG in Cowan C. S. M. and Leonard B. E. (eds): Microbes and the Mind. The Impact of the Microbiome on Mental Health, Modern Trends in Psychiatry, 32, pp. 134-143, doi: 10.1159/000510424 and available on https://doi.org/10.1159/000510424