Proceedings of The Physiological Society

Europhysiology 2018 (London, UK) (2018) Proc Physiol Soc 41, PCA119

Poster Communications

Inhibiting enteroendocrine T1R2/R3 glucose receptors reduces blood glucose and serum insulin responses

G. hellekant1, M. Bauer1, E. Kaplan1, T. Rose-Hellekant1

1. Departement of Biomedical Sciences, Medical School, Duluth, Minnesota, United States.

It is well established that T1R2 and T1R3 receptors, present in small intestine enteroendocrine cells, cause transient insertion of glucose transporter type 2 (GLUT2) into the apical membrane of enterocytes upon stimulation. This GLUT2 insertion facilitates glucose uptake and transport into the blood affecting blood glucose and insulin levels (1-3). This study reports effects of glucose gavage in mice with (WT) and without (CALHM1 KO) functioning intestinal T1R2/R3 receptors. We report KO mice generally have lower blood glucose and serum insulin levels than WT mice, suggesting the absence of functional intestinal T1R2 or T1R3 receptors decreases glucose uptake. We also utilized Gymnema sylvestre (GA) extract containing the stable, inhibiting polypeptide, gurmarin, to further investigate T1R2/R3's enteroendocrine role in postprandial glucose and insulin responses. To this end, WT and KO mice received 10% glucose gavage with and without extract from GA leaves. Glucose gavage with GA extract lowered blood glucose and serum insulin in WT mice but changed these parameters little in KO mice. Together, this data points to T1R2/R3's role in intestinal glucose absorption and implicates a possible target for lowering blood glucose and insulin with excessive carbohydrate consumption.

Where applicable, experiments conform with Society ethical requirements