Influence of cigarette smoking on the level of mRNA of somatostatin receptor 3 (SSTR3) in the gastric mucosa of patients with functional dyspepsia

Abstract

Helicobacter pylori (H. pylori) infection and smoking of cigarettes increase individual risk to gastric carcinoma. In stomach tumors, an expression of somatostatin receptor 3 (SSTR3) is diminished or completely lost. The purpose of these studies was to determine the influence of smoking cigarettes and H. pylori infection on the expression of SSTR3 in patients with functional dyspepsia. The study comprised 109 patients with functional dyspepsia in the age range 28-61 years. The total 218 biopsies used for analysis were divided into two groups: group I - 176 biopsies from non-smokers (72 from H. pylori positive ones), and group II - 42 biopsies from cigarette smokers (28 from H. pylori positive patients). The SSTR3 mRNA amount in the gastric mucosa (1 biopsy from the antrum and 1 biopsy from the corpus) was determined by real time RT-PCR. The presence of H. pylori colonization in the stomach tissue was evaluated by multiplex PCR. In the H. pylori negative samples the amount of the SSTR3 mRNA was significantly lower for smokers than for non-smokers (by 40%, p < 0.010). Infection with H. pylori caused reduction of the level of SSTR3 mRNA in non-smoking patients by ca. 30% (p < 0.01), while in samples from smokers the SSTR3 mRNA level was similar regardless of H. pylori infection. The cigarettes smoking and H. pylori infection are independent factors leading to decreasing of the SSTR3 mRNA level in gastric mucosa of patients with functional dyspepsia.