The intestinal microbiome, probiotics and prebiotics in neurogastroenterology

Abstract

The brain-gut axis allows bidirectional communication between the central nervous system (CNS) and the enteric nervous system (ENS), linking emotional and cognitive centers of the brain with peripheral intestinal functions. Recent experimental work suggests that the gut microbiota have an impact on the brain-gut axis. A group of experts convened by the International Scientific Association for Probiotics and Prebiotics (ISAPP) discussed the role of gut bacteria on brain functions and the implications for probiotic and prebiotic science. The experts reviewed and discussed current available data on the role of gut microbiota on epithelial cell function, gastrointestinal motility, visceral sensitivity, perception and behavior. Data, mostly gathered from animal studies, suggest interactions of gut microbiota not only with the enteric nervous system but also with the central nervous system via neural, neuroendocrine, neuroimmune and humoral links. Microbial colonization impacts mammalian brain development in early life and subsequent adult behavior. These findings provide novel insights for improved understanding of the potential role of gut microbial communities on psychological disorders, most particularly in the field of psychological comorbidities associated with functional bowel disorders like irritable bowel syndrome (IBS) and should present new opportunity for interventions with pro-and prebiotics.

Autism spectrum disorders and intestinal microbiota

“…7 Furthermore, a pro/ prebiotic-based therapy (e.g., Lactobacillus rhamnosus (JB-1), NCC4007, Bifidobacterium infantis, Bifidobacterium longum NCC3001, RO07, Lactobacillus helveticus R0052, Lactobacillus reuteri and Lactobacillus paracasei) was able to ameliorate the gastrointestinal symptoms that are frequently observed in children with ASDs. 5,54 MET therapy, which employs whole bacterial communities derived directly from the human GI tract (transplantation), showed positive results for different GI diseases (e.g., Clostridium difficile infection). 1 Nevertheless, no results are available for ASD patients.…”

Irritable bowel syndrome, the microbiota and the gut-brain axis

“…45,46 This colonization process depends heavily on birth mode. Vaginally born and breastfed infants are initially colonized by Bifidobacteriae, Lactobacilli and Bacteroides, and the full term infant's gut microbiome undergoes rapid maturation over the first year of age.…”

“…In early life colonization with beneficial microorganisms and development of a healthy microbiota must take place to ensure a normal development of the core stress axis (hypothalamic-pituitary-adrenal axis, HPA). 46 Stress induced norepinephrine production may stimulate proliferation of several other strains of enteric pathogens and enhance pathogenicity of Campylobacter jejuni. 104 Stressful stimuli may enhance permeability of the intestinal epithelium allowing bacterial antigens to to penetrate the gut epithelium and trigger an immune response most often resulting in a low-grade, but subclinical inflammation.…”

Modulatory Effects of Gut Microbiota on the Central Nervous System: How Gut Could Play a Role in Neuropsychiatric Health and Diseases

“…[13][14][15][16] Germ-free mice show developmental abnormality in the GI tract that can be reversed by reconstructing the gut microbiota, suggesting a role for gut microbiota in postnatal development of the enteric nervous system (ENS). 17,18 This period is also critical for the development of the CNS leading to the suggestion, based on experimental models, that gut microbiota may be an important factor participating in the development of cognitive, emotional, and behavioral processes shortly after birth. 19,20 For example, germ free mice show significant alteration in the concentration of the key neurotransmitters such as serotonin in the hypothalamus.…”