The intestines have their own nervous system, the ENS (enteric nervous system), which has over 500 million neurons. Scientists are investigating how ENS nerve cells communicate with brain neurons through the ‘gut-brain axis’. The latest research shows the actions of ENS neurons are affected by events in the gut environment, including the activities of bacteria that dwell there.

 

 

 

References:

Furness JB, Poole DP. Nonruminant nutrition symposium: Involvement of gut neural and endocrine systems in pathological disorders of the digestive tract. Journal of Animal Science. 2015; 90(4): 1203-1212. doi:10.2527/jas.2011-4825

Zhou L, Foster JA. Psychobiotics and the gut–brain axis: in the pursuit of happiness. Neuropsychiatric Disease and Treatment. 2015; 11: 715–723. doi https://dx.doi.org/10.2147/NDT.S61997

Kunze WA, Mao Y, Wang B, et al. Lactobacillus reuteri enhances excitability of colonic AH neurons by inhibiting calcium-dependent potassium channel opening. J. Cell. Mol. Med. 2009; 13(8B): 2261-2270. doi:10.1111/j.1582-4934.2009.00686.x

Forsythe P, Bienenstock J, Kunze WA. Vagal Pathways for Microbiome-Brain-Gut Axis Communication. In: Lyte M & Cryan JF, eds. Microbial Endocrinology: The Microbiota-Gut-Brain Axis in Health and Disease. New York: Springer; 2014:115-133.

Dinan TG, Cryan JF. The impact of gut microbiota on brain and behaviour: implications for psychiatry. Current Opinion in Clinical Nutrition & Metabolic Care. 2015; 18(6): 552–558. doi: 10.1097/MCO.0000000000000221

Bourassaa MW, Alima I, Bultmanc SJ, Ratan RR. Butyrate, neuroepigenetics and the gut microbiome: Can a high fiber diet improve brain health? Neuroscience Letters. 2016; 625(20): 56–63. doi:10.1016/j.neulet.2016.02.009

Luczynski P, Whelan SO, O’Sullivan C, Clarke G, et al. Adult microbiota-deficient mice have distinct dendritic morphological changes: differential effects in the amygdala and hippocampus. European Journal of Neuroscience. 2016; 44(1). doi: 10.1111/ejn.13291

Bercik P, Denou E, Collins J, Jackson W, et al. The Intestinal Microbiota Affect Central Levels of Brain-Derived Neurotropic Factor and Behavior in Mice. Gastroenterology. 2011; 141(2): 599-609. DOI: http://dx.doi.org/10.1053/j.gastro.2011.04.052

Li W, Dowd SE, Scurlock B, Acosta-Martinez V, Lyte M. Memory and learning behavior in mice is temporally associated with diet-induced alterations in gut bacteria. Physiology & Behavior. 2009; 96(4-5); 557-567. doi:10.1016/j.physbeh.2008.12.004

Mayer EA, Padua D, Tillisch K. Altered brain-gut axis in autism: comorbidity or causative mechanisms? Bioessays. 2014; 36(10):933-9. doi: 10.1002/bies.201400075.

Tillisch K, Labus J, Kilpatrick L, et al. Consumption of Fermented Milk Product With Probiotic Modulates Brain Activity. Gastroenterology. 2013; 144(7). doi: 10.1053/j.gastro.2013.02.043