Chronic inflammation in the brain is suspected in schizophrenia. Disruptions in the gastrointestinal microbiota and the immune system may also be involved.
Schizophrenia affects around 0.7% of the world’s population. This psychiatric disease is characterized by delirium and hallucinations, social isolation, and psychological disruption. Onset is most often in adolescence or young adulthood, between ages 15 and 25.
The gut-brain axis involved?
Schizophrenia is very often accompanied by gastrointestinal disorders. In fact the likelihood of experiencing psychiatric diseases such as schizophrenia may be related to chronic intestinal inflammation involving the immune system. The origin may be an imbalance in the intestinal microbiota (intestinal flora) that favors this inflammation. Disruptions in the microbiota have been found in schizophrenic patients, associated with an increase in intestinal permeability (bacteria and other substances that pass into the blood stream through the intestinal wall). These studies seem to indicate a key role played by the gut-brain axis in the development of the disease.
Acting on the composition of the microbiota
With these results, prevention and treatment options emerge: one of them being rebalancing the microbiota to reduce chronic inflammation. Studies have shown that the administration of probiotics can have anti-inflammatory properties by affecting the immune reaction, although to date, no treatment of this type has demonstrated its effectiveness on schizophrenia.
Inserm. Schizophrenie, dossier d'information réalisé avec Marie-Odile Krebs, Mai 2014, http://www.inserm.fr/thematiques/neurosciences-sciences-cognitives-neurologie-psychiatrie/dossiers-d-information/schizophrenie
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