Active immunisation against gastric inhibitory polypeptide (GIP) improves blood glucose control in an animal model of obesity-diabetes
AbstractRecent research suggests that long-term ablation of gastric inhibitory polypeptide (GIP) receptor signalling can reverse or prevent many of the metabolic abnormalities associated with dietary and genetically induced obesity-diabetes. The present study was designed to assess the sub-chronic effects of passive or active immunisation against GIP inob/obmice. Initial acute administration of GIP antibody together with oral glucose inob/obmice significantly increased the glycaemic excursion compared to controls (p<0.05). This was associated with a significant reduction (p<0.05) in the overall glucose-mediated insulin response. However, sub-chronic passive GIP immunisation was not associated with any changes in body weight, food intake or metabolic control. In contrast, active immunisation against GIP for 56 days in youngob/obmice resulted in significantly (p<0.05) reduced circulating plasma glucose concentrations on day 56 compared to controls. There was a tendency for decreased circulating insulin in GIP immunised mice. The glycaemic response to intraperitoneal glucose was correspondingly improved (p<0.05) in mice immunised against GIP. Glucose-stimulated insulin levels were not significantly different from controls. Furthermore, insulin sensitivity was similar in mice immunised against GIP and respective controls. Overall, the results reveal that active, as opposed to passive, immunisation against GIP improves blood glucose controlob/obmice.
Deletion of glycerol channel aquaporin-9 (Aqp9
) impairs long-term blood glucose control in C57BL/6 leptin receptor-deficient (db/db
) obese mice