title: G protein-coupled receptor 55 (GPR55) expresses differently in patients with Crohn's disease and ulcerative colitis.
abstract: OBJECTIVE
  To investigate the levels of G protein-coupled receptor 55 (GPR55) expression in colonic tissue of inflammatory bowel disease (IBD) patients and healthy controls, and its potential implication in IBD treatment.
  
  
  METHODS
  Fifty patients were enrolled in our prospective study: n = 21 with Crohn's disease (CD) and n = 16 with ulcerative colitis (UC); 19 women and 18 men. Control consisted of 13 non-IBD patients. In each subject, two biopsies were taken from different colonic locations. In IBD patients, biopsies both from endoscopically inflamed and non-inflamed areas were drawn and the development of inflammation confirmed in histopathological examination. GPR55 mRNA and protein expression were measured using real-time PCR and Western blot, respectively.
  
  
  RESULTS
  GPR55 expression at mRNA and protein level was detected in all samples tested. The level of GPR55 mRNA expression in non-inflamed colonic areas was comparable in all analyzed groups (p = .2438). However, in the inflamed tissues GPR55 mRNA expression was statistically significantly (p < .0001) higher (6.9 fold) in CD patients compared to UC. Moreover, CD patients manifested higher (12.5 fold) GPR55 mRNA expression in inflamed compared with non-inflamed colonic tissues (p < .0001). Although no significant differences were stated, GPR55 protein level tends to decrease in IBD as compared to control.
  
  
  CONCLUSIONS
  Different patterns of GPR55 expression at mRNA level were observed in IBD patients. We speculate that GPR55 is crucial for the mucosal inflammatory processes in IBD, particularly in CD and its expression may affect disease severity, and response to treatment. The GPR55 receptors may become an attractive target for novel therapeutic strategies in IBD.
authors.affiliation: a Department of Biochemistry , Medical University of Lodz , Lodz , Poland.|b Department of General and Colorectal Surgery , Medical University of Lodz , Lodz , Poland.
authors.forename: Marcin
authors.initials: M
authors.lastname: Włodarczyk
authors.affiliation: a Department of Biochemistry , Medical University of Lodz , Lodz , Poland.|c Department of Gastroenterology , Medical University of Lodz , Lodz , Poland.
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Sobolewska-Włodarczyk
authors.affiliation: d Department of Cytobiochemistry, Faculty of Biology and Environmental Protection , University of Lodz , Lodz , Poland.
authors.forename: Adam I
authors.initials: AI
authors.lastname: Cygankiewicz
authors.affiliation: d Department of Cytobiochemistry, Faculty of Biology and Environmental Protection , University of Lodz , Lodz , Poland.
authors.forename: Damian
authors.initials: D
authors.lastname: Jacenik
authors.affiliation: d Department of Cytobiochemistry, Faculty of Biology and Environmental Protection , University of Lodz , Lodz , Poland.
authors.forename: Wanda M
authors.initials: WM
authors.lastname: Krajewska
authors.affiliation: c Department of Gastroenterology , Medical University of Lodz , Lodz , Poland.
authors.forename: Krystyna
authors.initials: K
authors.lastname: Stec-Michalska
authors.affiliation: a Department of Biochemistry , Medical University of Lodz , Lodz , Poland.
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Piechota-Polańczyk
authors.affiliation: c Department of Gastroenterology , Medical University of Lodz , Lodz , Poland.
authors.forename: Maria
authors.initials: M
authors.lastname: Wiśniewska-Jarosińska
authors.affiliation: a Department of Biochemistry , Medical University of Lodz , Lodz , Poland.
authors.forename: Jakub
authors.initials: J
authors.lastname: Fichna
mesh_terms: D000328:Adult; D015153:Blotting, Western; D016022:Case-Control Studies; D003093:Colitis, Ulcerative / Q000235:genetics*; D003106:Colon / Q000378:metabolism / Q000473:pathology*; D003424:Crohn Disease / Q000235:genetics*; D005260:Female; D006801:Humans; D008297:Male; D011044:Poland; D011446:Prospective Studies; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D043882:Receptors, Cannabinoid; D043562:Receptors, G-Protein-Coupled / Q000235:genetics / Q000378:metabolism*
chemical_list: C524885:GPR55 protein, human; D012333:RNA, Messenger; D043882:Receptors, Cannabinoid; D043562:Receptors, G-Protein-Coupled
keywords: Crohn’s disease; G protein-coupled receptor 55; endocannabinoid system; inflammatory bowel diseases; ulcerative colitis