title: Does active Crohn's disease have decreased intestinal antioxidant capacity?
abstract: OBJECTIVE
  Oxidative stress is presumed to play an important role in Crohn's disease (CD) pathogenesis. Nevertheless, the evaluation of the intestinal antioxidant capacity through the analysis of glutathione peroxidase activity in CD remains to be determined.
  
  
  METHODS
  20 CD outpatients and 16 volunteers going through colonic cancer screening were enrolled. Colonoscopy with biopsies was performed in all individuals. Samples from inflamed and non-inflamed mucosa were taken when there was CD endoscopic activity. Spectrophotometric assays were performed to measure tissue glutathione peroxidase (GPx) activity, and total (GSHT) and oxidized (GSSG) glutathione in all samples. Demographics and clinical characteristics were collected from clinical charts.
  
  
  RESULTS
  Inflamed CD mucosa presented reduced GPx activity compared to non-inflamed CD mucosa (42.94mU/mg protein vs 79.62mU/mg protein, P<0.05) and control mucosa (42.94mU/mg protein vs 95.08mU/mg protein, P<0.001). GSHT concentration was reduced in inflamed mucosa when compared to non-inflamed CD mucosa (0.78μmol/g vs 1.98μmol/g, P<0.01) and the control group (0.78μmol/g vs 2.11μmol/g, P<0.001). A significant correlation was detected between GPx activity and GSSG (r=-0.599), disease duration (r=0.546), and thiopurine treatment (r=-0.480) in non-inflamed CD mucosa.
  
  
  CONCLUSIONS
  Our findings suggest that reduced GPx activity is present in inflamed CD mucosa. In addition, endoscopic activity, disease duration and thiopurine therapy could be associated with mucosal decreased antioxidant activity.
authors.affiliation: Departamento de Clínica Médica, Universidade Federal do Estado do Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Marco Antonio S
authors.initials: MA
authors.lastname: Pinto
authors.forename: Márcia Soares-Mota S
authors.initials: MS
authors.lastname: Lopes
authors.forename: Sálua T O
authors.initials: ST
authors.lastname: Bastos
authors.forename: Carolina L L
authors.initials: CL
authors.lastname: Reigada
authors.forename: Rafael F
authors.initials: RF
authors.lastname: Dantas
authors.forename: Jaime C B
authors.initials: JC
authors.lastname: Neto
authors.forename: Aderval S
authors.initials: AS
authors.lastname: Luna
authors.forename: Kalil
authors.initials: K
authors.lastname: Madi
authors.forename: Tiago
authors.initials: T
authors.lastname: Nunes
authors.forename: Cyrla
authors.initials: C
authors.lastname: Zaltman
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000975:Antioxidants / Q000378:metabolism; D001706:Biopsy; D001827:Body Height; D015992:Body Mass Index; D001835:Body Weight; D016022:Case-Control Studies; D003106:Colon / Q000737:chemistry / Q000378:metabolism* / Q000473:pathology*; D003113:Colonoscopy; D003424:Crohn Disease / Q000188:drug therapy / Q000201:enzymology* / Q000473:pathology*; D002149:Energy Intake; D005260:Female; D019803:Glutathione Disulfide / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000378:metabolism*; D006801:Humans; D007413:Intestinal Mucosa / Q000737:chemistry / Q000378:metabolism* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009752:Nutritional Status; D012643:Selenium / Q000097:blood; D012720:Severity of Illness Index; D013997:Time Factors; D055815:Young Adult
chemical_list: D000975:Antioxidants; D005979:Glutathione Peroxidase; D012643:Selenium; D019803:Glutathione Disulfide
keywords: Antioxidant capacity; Crohn's disease; Glutathione; Glutathione peroxidase; Oxidative stress