title: The possible mechanisms of Picrasma quassiodes (D. Don) Benn. in the treatment of colitis induced by 2,4,6-trinitrobenzene sulfonic acid in mice.
abstract: BACKGROUND
  Picrasma quassiodes (D. Don) Benn.(PQB) is used in folk medicines for the treatment of colds, upper respiratory infection, acute tonsillitis, acute gastroenteritis, bacillary dysentery and a variety of acute infectious diseases in Asia. Although recent reports indicate that PQB has antibacterial, and anti-inflammatory effects, its effects on colitis and its inhibitory mechanisms have not been previously reported.
  
  
  OBJECTIVE
  To assess the effects and the mode of action of the extract of Picrasma quassiodes (D. Don) Benn.(PQB) on a model of colitis in mice induced by trinitrobenzene sulfonic acid (TNBS).
  
  
  METHODS
  We induced mice colitis using TNBS/ethanol, then different doses of Picrasma quassiodes (D. Don) Benn.(PQB) extract (100, 200 and 400 mg/kg/day) and sulfasalazine (500 mg/kg/day) were administered by gavage for 7 days after the induction of colitis. The mice body weight, colonic wet weight, colonic lengths, myeloperoxidase (MPO) activity, macroscopic and histological colon injury were observed. Pro-inflammatory cytokines such as: tumor necrosis factor-alpha (TNF-α) and interleukin-8 (IL-8) were assayed by enzyme-linked immunoassay. The protein expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) in the colons were determined by immunohistochemical analysis.
  
  
  RESULTS
  PQB administration effectively prevented mice diarrhea, decreasing of the body weights, shortening of colon length and increasing of colon wet weight. Macroscopic and histological examinations also indicated that it was protected against colonic edema, ulceration and MPO activity elevation. Furthermore, PQB inhibited the abnormal secretions of pro-inflammatory cytokines, such as TNF-α and IL-8. Additionally, administration of PQB effectively inhibited COX-2 and iNOS protein expression.
  
  
  CONCLUSIONS
  These results suggest that PQB has an anti-inflammatory effect on TNBS-induced colitis due to the down-regulations of the productions and expressions of inflammatory mediators, and that it may be a potential inflammatory bowel disease (IBD) drug candidate.
authors.affiliation: Biomedicine Key Laboratory of Shaanxi Province, Northwest University, Xi'an 710069, PR China.
authors.forename: Wenna
authors.initials: W
authors.lastname: Zhao
authors.forename: Chen
authors.initials: C
authors.lastname: Sun
authors.forename: Jiao
authors.initials: J
authors.lastname: He
authors.forename: Lin
authors.initials: L
authors.lastname: Chen
authors.forename: Yongmin
authors.initials: Y
authors.lastname: Zhang
authors.forename: Wenji
authors.initials: W
authors.lastname: Sun
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology / Q000627:therapeutic use*; D003092:Colitis / Q000139:chemically induced / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D051546:Cyclooxygenase 2 / Q000378:metabolism; D016209:Interleukin-8 / Q000097:blood; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism; D009195:Peroxidase / Q000378:metabolism; D008517:Phytotherapy; D032270:Picrasma; D010936:Plant Extracts / Q000494:pharmacology / Q000627:therapeutic use*; D018547:Plant Stems; D014302:Trinitrobenzenesulfonic Acid; D014409:Tumor Necrosis Factor-alpha / Q000097:blood
chemical_list: D000893:Anti-Inflammatory Agents; D016209:Interleukin-8; D010936:Plant Extracts; D014409:Tumor Necrosis Factor-alpha; D014302:Trinitrobenzenesulfonic Acid; D009195:Peroxidase; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse; C077623:Ptgs2 protein, mouse; D051546:Cyclooxygenase 2