Effects of Exercise and Inhibition of Dipeptidyl Peptidase-4 on Insulin Secretion in Subjects With Type 1 Diabetes

Increasing evidence suggests pancreatic islet beta-cell regeneration occurs throughout the course of the disease in patients with type 1 diabetes. Therefore, decreased beta-cell mass in type 1 diabetes may be improved through inhibition of beta-cell destruction and stimulation of proliferation, even after prolonged duration of disease., Physical activity improves insulin secretion via unknown underlying mechanisms. We recently observed that Interleukin-6 induces glucagon like Peptide (GLP)-1 production and release from the islet alpha-cell and the intestinal L-cell. Furthermore, exercise induces release of Interleukin-6 from skeletal muscle resulting in elevated circulating Interleukin-6 levels. Therefore we hypothesize that exercise-induced Interleukin-6 promotes glucagon like peptide-1 secretion from the islet &agr;-cell and the intestinal L-cell, thereby providing a mechanism how physical activity can help maintain and improve beta-cell function in patients with type 1 diabetes. This mechanism can be enhanced by concomitant dipeptidyl peptidase-IV inhibition., Physical activity is also known to enhance insulin sensitivity and to attenuate the immune system activity., Therefore by combining physical activity and dipeptidyl peptidase-IV inhibition we aim to allow for beta-cell regeneration in a interventional randomized open-label study.