Neuropsychiatric disorders

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Evidence links the gut microbiota to various neuropsychiatric disorders such as anxiety, autism spectrum disorder, schizophrenia, depression and ADHD.[1][2][3][4][5] Neuropsychiatric disorders are thought to arise, in part, due to inflammation caused by pro-inflammatory substances that enter the bloodstream due to increased gut permeability associated with dysbiosis in the human gut microbiota.[2] In particular, lipopolysaccharide that is produced in the gut and permeates through the gut into the bloodstream increases the production of inflammatory cytokines that can alter brain function.[3] Additionally, the gut microbiota's role in neuropsychiatric disorders may be attributable to the production of neuroactive molecules by the microbiota that can cross the gut mucosa and the blood brain barrier and affect the central nervous system.[2]

Studies have demonstrated that the gut microbiota is changed in animal models for depression, autism spectrum disorder and anxiety like behavior however; this change has not been reproduced in the human microbiota in cases of depression.[5] Children with autism spectrum disorders show increased levels of Clostridium species[3] and decreased levels of Bacteroides species.[5] Also the species Desulfovibrio is found more commonly in the microbiota of children with autism sprectum disorders.[5]

Modulation of the gut microbiota resulting in behavioral changes in humans and animal models provides further evidence of a link between neuropsychiatric disorders and the microbiota. For example, the antibiotic vancomycin has been shown to improve behavior and communication in children with autism after only 8 weeks of treatment.[3]  Furthermore, modulation of the the microbiota using probiotics improves behavior in rodent models of anxiety and depression.[1] Increasing the biodiversity of the microbiota through dietary changes can also decrease anxiety-like behavior in rodents.[1]

  1. ^ a b c Liu, Xiaofei; Cao, Shangqing; Zhang, Xuewu (2015-09-16). "Modulation of Gut Microbiota–Brain Axis by Probiotics, Prebiotics, and Diet". Journal of Agricultural and Food Chemistry. 63 (36): 7885–7895. doi:10.1021/acs.jafc.5b02404. ISSN 0021-8561.
  2. ^ a b c Petra, Anastasia I.; Panagiotidou, Smaro; Hatziagelaki, Erifili; Stewart, Julia M.; Conti, Pio; Theoharides, Theoharis C. "Gut-Microbiota-Brain Axis and Its Effect on Neuropsychiatric Disorders With Suspected Immune Dysregulation". Clinical Therapeutics. 37 (5): 984–995. doi:10.1016/j.clinthera.2015.04.002. PMC 4458706. PMID 26046241.
  3. ^ a b c d Mangiola, Francesca. "Gut microbiota in autism and mood disorders". World Journal of Gastroenterology. 22 (1). doi:10.3748/wjg.v22.i1.361. PMC 4698498. PMID 26755882.{{cite journal}}: CS1 maint: unflagged free DOI (link)
  4. ^ Evrensel, Alper; Ceylan, Mehmet Emin (2015-12-31). "The Gut-Brain Axis: The Missing Link in Depression". Clinical Psychopharmacology and Neuroscience. 13 (3): 239–244. doi:10.9758/cpn.2015.13.3.239. ISSN 1738-1088. PMC 4662178. PMID 26598580.
  5. ^ a b c d Yarandi, Shadi S; Peterson, Daniel A; Treisman, Glen J; Moran, Timothy H; Pasricha, Pankaj J (2016-04-30). "Modulatory Effects of Gut Microbiota on the Central Nervous System: How Gut Could Play a Role in Neuropsychiatric Health and Diseases". Journal of Neurogastroenterology and Motility. 22 (2): 201–212. doi:10.5056/jnm15146. ISSN 2093-0879. PMC 4819858. PMID 27032544.