| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
-cell function during OGTT in metabolic disorders
1Metabolic Unit, Institute of Biomedical Engineering, National Research Council, 35127 Padua, Italy; and 2Division of Endocrinology and Metabolism, Department of Medicine 3, University of Vienna Medical School, A-1090 Vienna, Austria
Submitted 7 March 2002 ; accepted in final form 23 March 2003
The fasting proinsulin-to-insulin ratio is a currently used marker of 
-cell dysfunction. This ratio is calculated at the basal condition, but its behavior in dynamic conditions, i.e., during glucose stimulation, could be more informative. Given the different kinetics of the peptides, a mathematical model was necessary to analyze the oral glucose tolerance test (OGTT) data of insulin, C-peptide, and proinsulin in 55 healthy (NGT), 30 impaired glucose-tolerant (IGT), and 31 type 2 diabetic (T2DM) subjects. The model provided for secretion and disappearance of the peptides and an index of -cell function under dynamic conditions. Total proinsulin secretion during the OGTT was not different (P > 0.053) among NGT (0.17 ± 0.01 mmol/l in 3 h), IGT (0.22 ± 0.02), and T2DM (0.21 ± 0.02) subjects. The proinsulin-to-insulin molar ratio measured from basal samples was higher (P < 0.0001) in T2DM (0.39 ± 0.05) than in NGT (0.14 ± 0.01) and IGT (0.13 ± 0.02) subjects, and similar results (P < 0.003) were found by the dynamic index (0.27 ± 0.04, 0.14 ± 0.01, 0.15 ± 0.01 in T2DM, NGT, IGT subjects, respectively). The basal ratio significantly correlated with the dynamic index, and the regression line slope was lower than 1 (0.43 ± 0.08, 0.61 ± 0.10, and 0.56 ± 0.03 in NGT, IGT, and T2DM subjects, respectively, P < 0.0001). Impaired -cell function in T2DM could then be indicated by proinsulin-to-insulin indexes at both basal and dynamic phases.
proinsulin secretion; proinsulin clearance; impaired glucose tolerance; type 2 diabetes; mathematical modeling
This article has been cited by other articles:
|
|
 |
|
  M. A. Nauck, R. E. Ratner, C. Kapitza, R. Berria, M. Boldrin, and R. Balena Treatment With the Human Once-Weekly Glucagon-Like Peptide-1 Analog Taspoglutide in Combination With Metformin Improves Glycemic Control and Lowers Body Weight in Patients With Type 2 Diabetes Inadequately Controlled With Metformin Alone: A double-blind placebo-controlled study Diabetes Care, July 1, 2009; 32(7): 1237 - 1243. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. J. Goldstein, M. N. Feinglos, J. K. Lunceford, J. Johnson, D. E. Williams-Herman, and for the Sitagliptin 036 Study Group Effect of Initial Combination Therapy With Sitagliptin, a Dipeptidyl Peptidase-4 Inhibitor, and Metformin on Glycemic Control in Patients With Type 2 Diabetes Diabetes Care, August 1, 2007; 30(8): 1979 - 1987. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. Aschner, M. S. Kipnes, J. K. Lunceford, M. Sanchez, C. Mickel, D. E. Williams-Herman, and for the Sitagliptin Study 021 Group Effect of the Dipeptidyl Peptidase-4 Inhibitor Sitagliptin as Monotherapy on Glycemic Control in Patients With Type 2 Diabetes Diabetes Care, December 1, 2006; 29(12): 2632 - 2637. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. Ovalle and D. S.H. Bell Effect of Rosiglitazone Versus Insulin on the Pancreatic {beta}-Cell Function of Subjects With Type 2 Diabetes Diabetes Care, November 1, 2004; 27(11): 2585 - 2589. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. B. Buse, R. R. Henry, J. Han, D. D. Kim, M. S. Fineman, A. D. Baron, and for the Exenatide-113 Clinical Study Group Effects of Exenatide (Exendin-4) on Glycemic Control Over 30 Weeks in Sulfonylurea-Treated Patients With Type 2 Diabetes Diabetes Care, November 1, 2004; 27(11): 2628 - 2635. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
