DPP-4 Inhibitors Effect On Pancreas Islet ?-Cell Function And DPP-4 Inhibitors Effect On Pancreas Islet ?-Cell Function

Part One:DPP-4 inhibitors effect on pancreas islet ?-cell functionProgressive pancreas islet function failure is the key factor in the development of diabetes,including the secretion defect of ?-and a-cell and insulin resistance in the peripheral.How to improve islet function in patients with diabetes and delay the disease development has become the new hot therapeutic focus. Dipeptidyl peptidase-4(DPP-4) inhibitors (DPP-4I) is a new oral glucose-lowering drugs in recent years.Among various kinds of animal models,we can see that DPP-4 inhibitors could increase the beta-cell amount,restore the abnormal cell distribution in pancreas islet and then raise the insulin level in both the islet and plasma.In many clinical researches,although they use different drugs,dose,course and assessment,researchers observe that the insulin level is increased no matter in fasting or postprandial state,the insulin resistance is relived after the DPP-4I treatment .Except its effect on glucose regulation,DPP-4I also can improve ?-cell function,and the insulin resistance degree,BMI,course of disease don't effect its improvement.Part Two:DPP-4 inhibitors effect on pancreas islet ?-cell functionIn the normal, insulin and glucagon take part in the blood glucose regulation together to maintain the steady state.But in the people who have blood glucose regulation disorder,there is not only ?-cell dysfunction,bu also a-cell parasecretion with an abnormal high glucagon level.'Bi-hormonal theory,'which present that relatively or absolutely hypoinsulinemia and relative hyperglucagonemia raise hyperglycemia in diabetes,can more comprehensively reflect the pathogenesis of hyperglycemia. In most diabetes,we can see the glucagon is unusually elevated,with unclear mechanism.So far,the hyperglucagonemia may related in the lower reactivity of a-cell to glucose,the weakened insulin inhibition of glucagon,the dysregulation of incretin,the insulin resistance in ?-cell,the glucagon's promotion in ?-cell secretion,the dysregulation of nervous system,the primary dysfunction of ?-cell and so on.Dipeptidyl peptidase -4(DPP-4) inhibitors (DPP-4I),as a new oral glucose-lowering drugs in recent years,many research find that it can work on ?-cell, restore the abnormal cell distribution and hormone secretion with lowering glucagon level in many animal experiments.In clinical researches,whether take a DPP-4I for short-term or long-term,it can decrease the blood glucagon. This effect also can be observed in patients with IGT,TIDM and steroid diabetes.In a word,it can improve the ?-cell function to get a better blood glucose control.