Treatment with a proton pump inhibitor improves glycaemic control in Psammomys obesus, a model of type 2 diabetes

AIMS/HYPOTHESIS: Gastrin has been implicated in islet growth/neogenesis, and proton pump inhibitors (PPIs) have been shown to increase endogenous gastrin levels in animals and humans. Therefore, we investigated the effect of PPIs in a model of type 2 diabetes, Psammomys obesus. METHODS: P. obesus (morning blood glucose [mBG] 16.9 ± 0.6 mmol/l) were treated with vehicle or different doses (1–15 mg/kg) of lansoprazole for 17 days. RESULTS: Treatment with lansoprazole resulted in up to ninefold dose-dependent increases in endogenous gastrin levels (p < 0.05 for 10 mg/kg lansoprazole vs vehicle). There was a significant reduction in mBG levels in all animals in the high-dose lansoprazole groups during the 17 day treatment period, whereas there was no significant improvement in mBG in animals in the vehicle groups. The mBG at end of study was 18.2 ± 2.1, 8.7 ± 2.2 (p < 0.01), and 6.1 ± 2.3 (p < 0.001) mmol/l for vehicle and lansoprazole 10 and 15 mg/kg, respectively. The animals treated with 15 mg/kg lansoprazole, compared with vehicle, had a 2.3-fold increase in the intensity of insulin staining in beta cells (p=0.0002) and 50% higher beta cell mass (p=0.04). CONCLUSIONS/INTERPRETATIONS: The PPI lansoprazole had significant glucose-lowering effects in an animal model of type 2 diabetes, an effect that is most likely mediated through an increase in endogenous gastrin levels.