Expression of tryptophan hydroxylase in gastric mucosa in symptomatic and asymptomatic infection.

Introduction: infection induces clinical symptoms in 15-20% of subjects, and the reason for this variation is still not clear. The aim of the present study is to evaluate the expression of tryptophan hydroxylase (TpH-1) in gastric mucosa of patients with symptomatic and asymptomatic infection in relation to the intensity of bacterial colonization and severity of dyspeptic symptoms.

Material And Methods: Ninety subjects (aged 35-49 years) were enrolled in the study and separated into 3 groups of 30 subjects each. Group I - healthy volunteers without infection, group II - subjects with asymptomatic infection, group III - -infected patients with dyspeptic symptoms, mainly fasting and nocturnal epigastric pain. To diagnose infection the urea breath test (UBT-13C) and histological analysis were performed. The level of mRNA expression of tryptophan hydroxylase (TpH-1) was estimated in gastric mucosa with RT-PCR.

Results: The expression of this enzyme in antral mucosa was 2.69 ±0.97 in group I, 2.28 ±0.69 in group II ( > 0.05) and 4.40 ±1.64 in group III ( < 0.001). The levels of expression of TpH-1 in gastric body mucosa were 2.16 ±0.70, 1.57 ±0.52 ( > 0.05) and 3.40 ±1.51 ( < 0.001), respectively. In group III a positive correlation was found between intensity of colonization and TpH-1 expression as well as between TpH-1 expression and severity of dyspeptic symptoms.

Conclusions: Increased expression of TpH-1 in gastric mucosa plays a role in pathogenesis of chronic dyspepsia.