Serum motilin levels and motilin gene polymorphisms in children with functional constipation.

Background: Functional constipation is an important clinical problem among chidren all over the world. Its main cause is not completely understood. Motilin is a gastrointestinal hormone that increases intestinal motility. In this study, we aimed to investigate the serum motilin levels and its relationship with stool consistency and motilin gene polymorphisms in constipated children.

Methods: In this study we investigated 91 constipated patients (mean age 6.84±3.55 years) and 100 healthy controls (mean age 7.78±4.25 years). Serum motilin levels were assessed by sandwich enzyme-linked immunosorbent assay. rs2281820 (c.44 C>T) and rs2281818 (c.66 C>T) mutations were evaluated for motilin gene polymorphisms.

Results: Serum motilin levels were significantly lower in constipated children than healthy controls (6.20±7.86 vs. 11.54±17.89 pg/mL, respectively, P=0.008). Serum motilin levels were significantly correlated with Bristol stool scale rate (r=0.193, P=0.011) in whole study group, but in the constipation group there was no significant correlation (r=-0.072, P=0.528). There were no differences in terms of presence or distribution of the polymorphisms of rs2281820 (c.44 C>T) and rs2281818 (c.66 C>T) in both groups. There was not a significant difference between different polymorphism groups regarding serum motilin concentrations in whole study group and also in both of the study groups.

Conclusions: This study indicated for the first time that serum motilin levels decreased in constipated children. Further studies are needed to clarify whether motilin or motilin gene polymorphisms has a role in pathogenesis of functional constipation.