Effect of enprostil on omeprazole-induced hypergastrinemia and inhibition of gastric acid secretion in peptic ulcer patients

Hypergastrinemia in Long-Term Use of Proton Pump Inhibitors

BACKGROUND/AIM

The use of proton pump inhibitors (PPIs) is known to lead to hypergastrinemia; however, the data in patients with atrophic gastritis is still lacking. The aim of this study was to investigate the effects of long-term PPIs use on the gastrin levels in patients with atrophic gastritis and to determine factors affecting hypergastrinemia in long-term users of PPIs.

METHODS

Serum Helicobacter pylori IgG, gastrin and pepsinogen levels were measured. Atrophic gastritis was assessed by upper gastrointestinal endoscopies based on the Kimura-Takemoto classification and pepsinogen levels. CYP2C19 polymorphisms were assessed using DNA extracted from peripheral blood.

RESULTS

A total number of 382 patients (275 men and 107 women) were enrolled. Median serum gastrin levels were higher in PPI users than in non- users (234 vs. 113 pg/mL, p < 0.001) and in women than in men (252 vs. 155 pg/mL, p = 0.006). Gastrin levels were significantly associated with corpus atrophy only in the subgroup of non-users of PPIs. Multivariate analysis revealed that hypergastrinemia (over 150 pg/mL) was significantly associated with PPI use (OR 5.30; 95% CI 3.32-8.47), women (OR 2.22; 95% CI 1.33-3.72) and corpus atrophy (OR 1.82; 95% CI 1.14-2.90).

CONCLUSION

PPI use, women and corpus atrophy were risk factors for hypergastrinemia. Gender, but not corpus atrophy, affected the gastrin levels in long-term users of PPIs.

Effect of hypergastrinemia on pancreatic carcinogenesis

BACKGROUND

Previous studies in our laboratory demonstrated that pancreatic carcinomas in rodents express receptors for the peptide hormone gastrin that are not present in normal adult pancreas. In view of an abundant literature suggesting that gastrin may promote growth of various gastrointestinal tissues and tumors, the effect of hypergastrinemia on the process of pancreatic carcinogenesis was evaluated.

METHODS

Rats received subcutaneous injections of the pancreatic carcinogen azaserine at 19 and 26 days of age. Starting at 12 months of age, animals were randomized to treatment with the proton pump inhibitor lansoprazole or vehicle by gavage for 6 months. At autopsy, pancreatic wet weight normalized to body weight was recorded, as well as the number of benign and malignant pancreatic lesions.

RESULTS

Serum gastrin levels were determined by radioimmunoassay and showed a greater than two-fold increase in lansoprazole-treated animals. Pancreatic wet weight in hypergastrinemic rats was increased compared to controls (p <0.05). Premalignant lesions such as acidophilic atypical acinar cell foci, adenomas, heterogeneous phenotypic populations of nodules within nodules, and carcinoma-in-situ were not increased in the hypergastrinemic group. Likewise, there was no difference in the incidence of invasive carcinoma in hypergastrinemic animals (10%) compared to controls (5.7%).

CONCLUSION

Hypergastrinemia stimulated an increase in pancreatic weight, but did not stimulate development of premalignant lesions or progression to cancer in the azaserine model of rat pancreatic acinar cell carcinoma.