Gut—brain axis

Enteric nerves control intestinal smooth muscle action and are connected to the brain by the autonomic nervous system. IBS is thought to result from dysregulation of this brain-gut axis. The enteric nervous system is composed of two gan-glionated plexuses that control gut innervation the submucous plexus (Meissner s plexus) and the myenteric plexus (Auerbach s plexus). The enteric nervous system and the central nervous system (CNS) are interconnected and interdependent. A number of neurochemicals mediate their function, including serotonin (5-hydroxytryptamine or 5-HT), acetylcholine, substance P, and nitric oxide, among others. 

Aziz Q, Thompson DG. Brain-gut axis in health and disease. Gastroenterology 1998 114 559-78. 

Figure 12.1. Two axes define the properties of foods Horizontal, the fork-to-farm (demand) axis vertical, the gut-brain axis.

Existing health targets, as described above, will be further investigated and either confirmed or refuted for probiotic efficacy. New targets will also certainly emerge. Many of these targets will be indicated by the substantial research efforts towards understanding of the intestinal and other microbiota. The influence of the intestinal microbiota on, for instance, the gut-brain axis may hint at possibilities for probiotics and stress or mental awareness. 

The identification of a tissue containing the receptor of interest or the transient or stable cloning and expression in cells is the first step in developing a reliable RRA. While the brain-spinal cord axis represents a major source of receptors, assays based on receptors specific to tissues including gut, platelets, lymphocytes, skeletal muscle, and endocrine organs are well known. Transformed cells are also useful as the point of departure to gather receptors these may be obtained from public sources such as the American Type Culture Collection (Rockville, MD, USA). Cloned and expressed receptors may be obtained on an individual basis as needed. 

Diet and the Gut Microbiota — How the Gut Brain Axis Impacts on Autism... 

The gutibrain axis as a communication highway between the external environment and human brain has important "internal" turnpikes in the shape of the human gut microbiota through which many nutrients and ingested chemicals must pass before being converted into biologically available and active intermediates which... 

Stilling RM, Dinan TG, Cryan JF. Microbial genes, brain behaviour — epigenetic regulation of the gut—brain axis. Genes Brain Behav. 2014 13 69-86. 

Udit S, Gautron L (2013) Molecular anatomy of the gut-brain axis revealed with transgenic technologies implications in metabolic research. Front Neurosci. doi 10.3389/fhins.2013. 00134... 

Cryan, J.F. and O Mahony, S. M. (2011) The microbiome-gut-brain axis from bowel to behavior. Neurogastroenterology 136, 2003-2014. 

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