Is melatonin involved in the irritable bowel syndrome?

There is a substantial evidence that large quantities of melatonin are produced in gastrointestinal tract, however, is still unclear which is the role of melatonin in digestive system in human physiology and pathophysiology. In the present study we investigated urinary excretion of a main melatonin metabolite, 6-sulphatoxymelatonin, in patients with irritable bowel syndrome (IBS). The investigation was carried out in 67 persons, both sexes, aged 20-45 years old who according to Rome III Criteria were diagnosed as sufferers of constipation (C-IBS, n=21 persons) or diarrhoea (D-IBS, n=24 persons) form of irritable bowel syndrome and as healthy subjects (K, n=22), matched for control. Samples were obtained from the collected diurnal urine. The concentration of 6-sulphatoxymelatonin (6-SMLT) was measured with ELISA method, creatinine (crea) was automatically analyzed with biochemical analyzer and 6-SMLT/crea calculated. There were statistically significant differences between groups: the 6-SMLT/crea level was lower in C-IBS (103.86+/- 82.83 ng/mg) and D-IBS (112.72+/-85.29 ng/mg) groups compared to K group (202.7+/-89.28 ng/mg), respectively, p=0.002, p=0.003. There were no differences between C-IBS and D-IBS groups, however, there were observed differences between men and women with C-IBS. The 6-SMLT/crea. level was higher in women with C-IBS (139.31+/-96.45) compared to men with C-IBS (35.51+/-41.05) (p=0.04). These results suggest that different melatonin secretion and metabolism may be involved in the pathogenesis of irritable bowel syndrome.

[Methylenetetrahydrofolate reductase gene polymorphism in patients with type 2 diabetes]. / Polimorfizm genu reduktazy metylenotetrahydrofolianu u pacjentów z cukrzyca typu 2.

Hyperhomocysteinemia is recognised as a risk factor of ischaemic heart disease and vascular complications of arterial hypertension. Methylenetetrahydrofolate reductase (MTHFR) gene C677T polymorphism is associated with hyperhomocysteinaemia. The aim of the study was the assessment of an association of the above polymorphism with type 2 diabetes with special attention to myocardial infarction and arterial hypertension accompanying diabetes. The study group consisted of 172 type 2 diabetics. 172 control subjects with normal glucose tolerance were age and sex matched to patients with diabetes. C677T polymorphism in MTHFR gene locus was detected using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) method. CT and TT genotypes were found more often among diabetics (OR 1.83, 95% CI 1.16-2.89; p < 0.01). This finding may be secondary to the excess of T allele bearers among diabetics with myocardial infarction when compared to diabetics without infarction and to control group. Upon obtained results the potential role of genotypes CT and TT as risk factors of myocardial infarction among patients with type 2 diabetes could not be excluded (OR 2.33, 95% CI 0.93-5.8; p = 0.07). Genotypes containing T allele are not associated with diabetes type 2 and concomitant arterial hypertension (OR 1.45, 95% CI 0.89-2.57; p = 0.14). A confirmation in further studies is needed for the presented findings.