The impact of the gut microbiome on human psychological state

The purpose: to analyze some assumptions regarding the likely impact of the microbiome on the psychological state of a person on the basis of the latest foreign and domestic studies of the microbial composition of the macroorganism and the normorbiota as a whole.

Results. The state of human health depends on nutrition, as the most important factor regulating human microbiota. Depressive symptoms are triggered by increased consumption of foods high in fat and sugar and are the long-term consequences of these unhealthy eating habits. Microbial changes caused by poor nutrition can provoke and exacerbate depressive symptoms. At the same time, adjusting nutrition, on the contrary, can prevent the development of depression. Gut microbiota produces a wide range of compounds that are important for the body: all major neurotransmitters, including serotonin, cytokines, tryptophan, and short-chain fatty acids. Serotonin deficiency is considered a significant causal factor in the development of anxiety, affective disorders and stress. Inflammation, oxidative stress, intestinal microbiome, epigenetic modifications and neuroplasticity are considered among the main neurobiological pathways of the formation of mental disorders. In the context of nutraceutical intervention, omega-3 fatty acids, folate, S-adenosylmethionine, N-acetylcysteine, and probiotics are considered promising for future research.

Conclusion. A two-way relationship between the gut microbiome and the central nervous system has been established through direct and indirect pathways: the hypothalamic-pituitary-adrenal system, the immune system, and the autonomic nervous system.

References

1. Agus A., Planchais J., Sokol H. (2018) Gut Microbiota Regulation of Tryptophan Metabolism in Health and Disease. Cell Host Microbe, 23(6): 716–724. doi: 10.1016/j.chom.2018.05.003.
2. Balakumar M., Prabhu D., Sathishkumar C. et al. (2018) Improvement in glucose tolerance and insulin sensitivity by probiotic strains of Indian gut origin in high-fat diet-fed C57BL/6J mice. Eur. J. Nutr., 57(1): 279–295.
3. Bested A.C., Logan A.C., Selhub E.M. (2013) Intestinal microbiota, probiotics and mental health: from Metchnikoff to modern advances: Part I — autointoxication revisited. Gut Pathog., 5(1): 5. doi: 10.1186/1757-4749-5-5.
4. Comai S., Bertazzo A., Brughera M., Crotti S. (2020) Tryptophan in health and disease. Adv. Clin. Chem., 95: 165–218. doi: 10.1016/bs.acc.2019.08.005.
5. Dinan T.G., Cryan J.F. (2017) The Microbiome-Gut-Brain Axis in Health and Disease. Gastroenterol Clin. North Am., 46(1): 77–89. doi: 10.1016/j.gtc.2016.09.007.
6. Gomaa E.Z. (2020) Human gut microbiota/microbiome in health and diseases: a review. Antonie Van Leeuwenhoek, 113(12): 2019–2040. doi: 10.1007/s10482-020-01474-7.
7. Finegold S.M., Molitoris D., Song Y. et al. (2002) Gastrointestinal microflora studies in late-onset autism. Clin. Infect. Dis., 35 (Suppl. 1): S6–S16. doi: 10.1086/341914.
8. Hosseinifard E.S., Morshedi M., Bavafa-Valenlia K., Saghafi-Asl M. (2019) The novel insight into anti-inflammatory and anxiolytic effects of psychobiotics in diabetic rats: possible link between gut microbiota and brain regions. Eur. J. Nutr., 58(8): 3361–3375.
9. Marchenko A.V., Loban G.A., Petrushanko T.O. et al. (2020) The effect of the psycho-emotional stress on the state of microbiota of the gingival sulcus. Світ медицини та біології, 3(73): 69–74. doi:10.26724/2079-8334-2020-3-73-74-77.
10. Morshedi M., SaghafiAsl M., Hosseinifard E.S. (2020) The potential therapeutic effects of the gut microbiome manipulation by synbiotic containing Lactobacillus plantarum on neuropsychological performance of diabetic rats. J. Transl. Med., 18(1): 18.
11. Morshedi M., Valenlia K.B., Hosseinifard E.S. et al. (2018) Beneficil psychological effects of novel psychobiotics in diabetic rats: the interaction among the gut, blood and amygdala. J. Nutr. Biochem., 57: 145–152.
12. Moser G., Fournier C., Peter J. (2018) Intestinal microbiome-gut-brain axis and irritable bowel syndrome. Wien Med. Wochenschr., 168(3–4): 62–66. doi: 10.1007/s10354-017-0592-0.
13. O’Mahony S.M., Clarke G., Borre Y.E. et al. (2015) Serotonin, tryptophan metabolism and the brain-gut-microbiome axis. Behav. Brain Res., 277: 32–48. doi: 10.1016/j.bbr.2014.07.027.
14. Singh R.K., Chang H.W., Yan D. et al. (2017) Influence of diet on the gut microbiome and implications for human health. J. Transl. Med., 15(1): 73. doi: 10.1186/s12967-017-1175-y.
15. Starovoitova S. (2018) Probiotics as a remedy against stress. Eurasian J. Applied Biotechnolog., 2: 1–11.
16. Cryan J.F., O’Riordan K.J., Cowan C.S.M. et al. (2019) The Microbiota-Gut-Brain Axis. Physiol. Rev., 99(4): 1877–2013. doi: 10.1152/physrev.00018.2018.