Brief Article
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World J Gastroenterol. Jun 7, 2011; 17(21): 2646-2651
Published online Jun 7, 2011. doi: 10.3748/wjg.v17.i21.2646
Secretion of melatonin and 6-sulfatoxymelatonin urinary excretion in functional dyspepsia
Cezary Chojnacki, Tomasz Poplawski, Grażyna Klupinska, Janusz Blasiak, Jan Chojnacki, Russel J Reiter
Cezary Chojnacki, Grażyna Klupinska, Jan Chojnacki, Department of Gastroenterology, Medical University of Lodz, 90-647 Lodz, Poland
Tomasz Poplawski, Janusz Blasiak, Department of Molecular Genetics, University of Lodz, 90-131 Lodz, Poland
Russel J Reiter, Department of Cellular and Structural Biology, University of Texas Health Science Center, San Antonio, TX 78229-3901, United States
Author contributions: Chojnacki C conceived the study, screened the patients, and carried out the clinical procedures; Poplawski T carried out the biochemical analysis; Klupinska G participated in study design; Blasiak J performed the statistical analysis and helped to draft the paper; Chojnacki J participated in the study design and wrote the final version of the paper; Reiter RJ interpreted the data.
Correspondence to: Dr. Cezary Chojnacki, Department of Gastroenterology, Medical University of Lodz, 1 Haller’s Square, 90-647 Lodz, Poland. gastrologia@umed.lodz.pl
Telephone: +48-42-6393049  Fax: +48-42-6393049
Received: November 25, 2010
Revised: March 5, 2011
Accepted: March 12, 2011
Published online: June 7, 2011
Abstract

AIM: To evaluate blood concentration of melatonin and urinary excretion of its metabolite, 6-sulfatoxymelatonin (6-OHMS), in functional dyspepsia (FD).

METHODS: Ninety individuals were enrolled in the study: 30 in each study group: patients with postprandial distress syndrome (PDS), epigastric pain syndrome (EPS), and controls. Blood samples were drawn at 02:00 and 09:00 h and 24-h urine collection was performed. Serum melatonin and urinary 6-OHMS concentrations were measured by enzyme-linked immunosorbent assay.

RESULTS: Serum melatonin concentration at night and in the morning was significantly (P < 0.001) higher in PDS patients [at 02:00 h-93.3 pg/mL, quartile range (QR): 79.8-116.2; at 09.00 h-14.3 pg/mL, QR: 7.06-19.0] than in EPS (57.2 pg/mL, QR: 42.6-73.1; 8.1 pg/mL, QR: 4.1-9.3) and control patients (57.7 pg/mL, QR: 51.2-62.5; 8.1 pg/mL, QR: 5.4-10.3). A similar relationship was observed for urinary 6-OHMS excretion. Patients with severe PDS symptoms had a higher melatonin concentration than these with moderate syndromes, whereas patients with severe EPS had a lower urinary 6-OHMS excretion than patients with moderate symptoms.

CONCLUSION: Evaluation of melatonin serum concentrations and 24-h urinary 6-OHMS excretion are useful methods for differential diagnosis of various clinical forms of FD.

Keywords: Functional dyspepsia, Postprandial distress syndrome, Epigastric pain syndrome, Melatonin, 6-sulfatoxymelatonin