Evaluation Of Islet α-cell And β-cell Function At Different Level Of HbA1c In Patients With Newly Diagnosed Type 2 Diabetes Mellitus

Objective:To investigate the change of islet α-cell and β-cell function at different level of HbA1 c in patients with newly diagnosed T2 DM.Methods:A total of 269 newly diagnosed T2 DM patients were divided into four groups according to their HbA1 c level.Oral glucose tolerance test（OGTT）,insulin releasing test,and glucagon releasing.The islet α-cell and β-cell fuction was assayed by homeostasis model assessment for insulin resistance（HOMA-IR）,homeo stasis model assessment for β-cell function（HOMA-β）,early insulin secretion index（△I30/△G30）,and second-phase insulin secretion index [using area under curve of insulin(AUC_INS)],glucagon,glucagon/insulin and area under curve of glucagon(AUC_glu)among the four groups,and a correlation analysis was performed between Hb A1 c and other indicators.Result:（1）There was a good correlation between Hb A1 c and pancreatic beta cells（p<0.05）,and there was no significant correlation between islet cells and pancreatic islets（p>0.05）.（2）Glucagon,AUCglu was no significant different and glucagon/insulin increased significantly（p<0.05）with the increase of Hb A1 c.Conclusion: There was no correlation between HbA1 c and the islet beta cells,but not with islet α-cells.With the increase of Hb A1 c level,the secretion function of beta cells gradually decreased,ach phase to reduce the secretion of insulin,glucagon absolute value has no significant change,but glucagon / insulin ratio increases,exacerbated by elevated blood glucose in patients with type 2 diabetes.