title: Calcitonin gene-related peptide is a promising marker in ulcerative colitis.
abstract: BACKGROUND
  Assessment of the severity and extent of disease activity continues to present challenges for physicians in the treatment of ulcerative colitis. Standard markers that can objectively reflect disease activity are useful for physicians to both evaluate the course of ulcerative colitis and monitor the effectiveness of therapy for any given patient.
  
  
  OBJECTIVE
  We hypothesize that calcitonin gene-related peptide (CGRP) can reflect the activity and severity of ulcerative colitis and be used as a marker to assess the effectiveness of various therapies.
  
  
  METHODS
  We examined the expression levels of CGRP by reverse transcription polymerase chain reaction (RT-PCR) and semi-quantitative immunohistochemisty in mucosal biopsies from 38 patients with UC and 18 controls. Levels of CGRP mRNA and protein expression were compared between patients and controls with the clinical activity index (CAI) and the endoscopic activity index (EAI) for various levels of UC severity.
  
  
  RESULTS
  Our results showed that the levels of CGRP mRNA and protein expression were significantly reduced in UC patients compared to controls. This effect was more pronounced in patients with more severe cases of UC. There is a statistically significant negative correlation between levels of CGRP mRNA expression and CAI/EAI scores. A statistically significant negative correlation was also found between levels of CGRP protein expression and CAI/EAI scores. Overall, high CAI and EAI scores were accompanied by low CGRP mRNA and protein expression levels.
  
  
  CONCLUSIONS
  Levels of CGRP protein and mRNA expression in the colonic mucosa of patients are closely associated with UC severity and corroborate traditional indices used to assess the disease.
authors.affiliation: Department of Gastroenterology, 2nd Xiangya Hospital, Central South University, Changsha, 410008, China.
authors.forename: Fu-Jun
authors.initials: FJ
authors.lastname: Li
authors.forename: Yi-You
authors.initials: YY
authors.lastname: Zou
authors.forename: Yi
authors.initials: Y
authors.lastname: Cui
authors.forename: Yani
authors.initials: Y
authors.lastname: Yin
authors.forename: George
authors.initials: G
authors.lastname: Guo
authors.forename: Fang-Gen
authors.initials: FG
authors.lastname: Lu
mesh_terms: D000328:Adult; D000818:Animals; D015415:Biomarkers; D015740:Calcitonin Gene-Related Peptide / Q000097:blood / Q000235:genetics / Q000378:metabolism*; D003093:Colitis, Ulcerative / Q000097:blood / Q000235:genetics / Q000378:metabolism*; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012720:Severity of Illness Index; D055815:Young Adult
chemical_list: D015415:Biomarkers; D012333:RNA, Messenger; D015740:Calcitonin Gene-Related Peptide