title: Similarity in the metabolic profile in macroscopically involved and un-involved colonic mucosa in patients with inflammatory bowel disease: an in vitro proton ((1)H) MR spectroscopy study.
abstract: BACKGROUND
  The histological extent of inflammatory bowel disease (IBD) is greater than that evident by colonoscopic evaluation. We hypothesized that metabolic profile in macroscopically un-involved colonic mucosa in IBD is similar to that of controls with healthy colon. We thus assessed the differences in metabolic profile in macroscopically involved and un-involved colonic mucosa of IBD patients to further substantiate the extent of disease.
  
  
  METHODS
  Colonic mucosal biopsies were obtained and snap frozen from both the macroscopically un-involved and involved colonic mucosa of IBD patients and macroscopically normal colonic mucosa of controls and were subjected to in-vitro high-resolution proton ((1)H) magnetic resonance (MR) spectroscopy and the concentrations of metabolites were determined.
  
  
  RESULTS
  Thirty-two metabolites were assigned in the proton MR spectrum of colonic mucosa of IBD patients. The concentrations of amino acids (isoleucine, leucine, valine, arginine, lysine, glutamine/glutamate, alanine), membrane metabolites (choline, glycerophosphorylcholine/phosphorylcholine), glycolytic product (lactate) and short chain fatty acid (formate) were significantly lower while significantly high level of glucose were observed in the macroscopically un-involved colonic mucosa of IBD patients compared to the macroscopically normal mucosa of controls. There was no significant difference in the concentrations of metabolites in macroscopically involved and un-involved colonic mucosa of IBD patients.
  
  
  CONCLUSIONS
  The metabolic profile in macroscopically un-involved colonic mucosa of IBD patients is similar to that of macroscopically involved mucosa but different from colonic mucosa of controls. This suggests that even macroscopically un-involved colonic mucosa is metabolically abnormal and may explain the increase in extent of disease with time.
authors.affiliation: Department of NMR and MRI Facility, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Uma
authors.initials: U
authors.lastname: Sharma
authors.forename: Rajiv R
authors.initials: RR
authors.lastname: Singh
authors.forename: Vineet
authors.initials: V
authors.lastname: Ahuja
authors.forename: Govind K
authors.initials: GK
authors.lastname: Makharia
authors.forename: Naranamangalam R
authors.initials: NR
authors.lastname: Jagannathan
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000378:metabolism*; D001704:Biopolymers / Q000378:metabolism*; D003106:Colon / Q000378:metabolism*; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000378:metabolism*; D007413:Intestinal Mucosa / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D011522:Protons
chemical_list: D015415:Biomarkers; D001704:Biopolymers; D011522:Protons