Is Insulin Resistance and/or Glucose Intolerance Pathogenetic in the Development of a Reduced Incretin Effect
The purpose of this study is to examine whether there is a causal relationship between insulin resistance and/or glucose intolerance in the development of a defect incretin effect.
|Study Design:||Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: Open Label
|Official Title:||Is Insulin Resistance and/or Glucose Intolerance Pathogenetic in the Development of a Reduced Incretin Effect|
- Incremental GLP-1 response during the mixed meal test. Assessed as AUC during the 4 hour test. [ Time Frame: 4 hours (during the mixed meal test) ] [ Designated as safety issue: No ]
|Study Start Date:||November 2008|
|Study Completion Date:||September 2009|
|Primary Completion Date:||August 2009 (Final data collection date for primary outcome measure)|
2mg morning and night for 5 days.
In this study we are going to examine the incretin effect before and after the development of insulin resistance and/or glucose intolerance. The incretin effect is the increased insulin response seen after an oral as apposed to an intravenous glucose challenge with identical plasma glucose profiles. This insulin enhancing effect is greatly reduced in type 2 diabetes.
Since the development of type 2 diabetes is preceded by insulin resistance and glucose intolerance we wanted to examine the incretin effect in the early stages of type 2 diabetes.
To do this, we want to induce insulin resistance and/or glucose intolerance. This is achieved by 5 days of treatment with dexamethasone.
The incretin effect in this study will be examined by 3 investigations prior to the treatment and 3 days following the treatment.
Day 1: Oral glucose challenge with 75 g of glucose.
The subject is asked to drink 75g of glucose suspended in 300mL of water. During the 4 hours of the test, we draw blood at various times during the study to determine the concentration of: Glucose, GLP-1, GIP, Glucagon, Insulin and c-peptide.
Day 2: Intravenous glucose
We duplicate the glucose curve obtained from day 1. We also draw blood during this test to the same end as in day 1.
Day 3: Mixed meal.
The subjects are served a mixed meal. During this 4 hour test, we draw blood to examine the response to a standardized meal. The test involves sampling blood as described for the other days.
Please refer to this study by its ClinicalTrials.gov identifier: NCT00784745
|Copenhagen, Denmark, 2300|
|Principal Investigator:||Thure Krarup, dr. med.||Bispebjerg Hospital|