title: Stress-induced corticotropin-releasing hormone-mediated NLRP6 inflammasome inhibition and transmissible enteritis in mice.
abstract: OBJECTIVE
  Stress alters brain-gut interactions and could exacerbate intestinal disorders, including irritable bowel syndrome. Alterations in the intestinal microbiota have been associated with irritable bowel syndrome. Maintenance of healthy microbiota requires nucleotide-binding oligomerization domain protein-like receptors, pyrin-domain containing (NLRP)-6 inflammasomes. We investigated the involvement of NLRP6 in water-avoidance stress (WAS)-induced intestinal disorders in mice.
  
  
  METHODS
  B57BL6 mice were subjected to WAS for 1 hour each day for 10 days; body weights and intestinal inflammation and permeability were analyzed. We investigated signaling via the NLRP3 and NLRP6 inflammasomes, and the role of corticotropin-releasing hormone (CRH) in WAS-associated inflammation and NLRP6 inhibition. Mice that were not exposed to stress were co-housed with mice subjected to WAS to determine the effects of WAS-induced dysbiosis, measured by sequencing bacterial 16S ribosomal RNA. We also assessed the effects of a peroxisome proliferator-activated receptor-γ agonist and probiotics.
  
  
  RESULTS
  WAS-induced small-bowel inflammation (enteritis) was associated with inhibition of NLRP6, but not NLRP3, and was prevented by a peroxisome proliferator-activated receptor-γ agonist, which induced epithelial expression of NLRP6. CRH was released during WAS and inhibited NLRP6 expression. WAS induced alterations in the gut microbiota of mice; co-housed nonstressed mice developed enteritis associated with increased CRH and decreased levels of NLRP6. Probiotic therapy reduced intestinal inflammation in mice with WAS-induced enteritis.
  
  
  CONCLUSIONS
  Exposure of mice to stress inhibits NLRP6 and alters the composition of the gut microbiota, leading to intestinal inflammation. These findings might explain the benefits of probiotics for patients with stress-associated gastrointestinal disorders.
authors.affiliation: Department of Microbiology, Shandong University School of Medicine, Jinan, Shandong, China.
authors.forename: Yundong
authors.initials: Y
authors.lastname: Sun
authors.forename: Min
authors.initials: M
authors.lastname: Zhang
authors.forename: Chun-Chia
authors.initials: CC
authors.lastname: Chen
authors.forename: Merritt
authors.initials: M
authors.lastname: Gillilland
authors.forename: Xia
authors.initials: X
authors.lastname: Sun
authors.forename: Mohamad
authors.initials: M
authors.lastname: El-Zaatari
authors.forename: Gary B
authors.initials: GB
authors.lastname: Huffnagle
authors.forename: Vincent B
authors.initials: VB
authors.lastname: Young
authors.forename: Jiajie
authors.initials: J
authors.lastname: Zhang
authors.forename: Soon-Cheol
authors.initials: SC
authors.lastname: Hong
authors.forename: Yu-Ming
authors.initials: YM
authors.lastname: Chang
authors.forename: Deborah L
authors.initials: DL
authors.lastname: Gumucio
authors.forename: Chung
authors.initials: C
authors.lastname: Owyang
authors.forename: John Y
authors.initials: JY
authors.lastname: Kao
mesh_terms: D000818:Animals; D003346:Corticotropin-Releasing Hormone / Q000502:physiology*; D004195:Disease Models, Animal; D004751:Enteritis / Q000209:etiology* / Q000628:therapy; D005260:Female; D058847:Inflammasomes / Q000378:metabolism; D043183:Irritable Bowel Syndrome / Q000503:physiopathology / Q000523:psychology; D054892:Metagenome / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D047495:PPAR gamma / Q000819:agonists; D019936:Probiotics / Q000627:therapeutic use; D011956:Receptors, Cell Surface / Q000502:physiology*; D013315:Stress, Psychological / Q000150:complications / Q000503:physiopathology*
chemical_list: D058847:Inflammasomes; C559901:Nod-like receptor pyrin domain-containing protein 6, mouse; D047495:PPAR gamma; D011956:Receptors, Cell Surface; D003346:Corticotropin-Releasing Hormone