A Pilot Study to Evaluate the Glucagon-Like Peptide 1 Response to the Challenge of Mixed Meals in Chinese Subjects (IC-1-V1)
|The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.|
|ClinicalTrials.gov Identifier: NCT00884091|
Recruitment Status : Completed
First Posted : April 20, 2009
Last Update Posted : December 6, 2011
|Condition or disease|
Glucagon-like peptide 1 (GLP-1) is a 30-amino acid peptide produced in the intestinal epithelial endocrine L-cells. It stimulates insulin and suppresses glucagons secretion, inhibits gastric emptying, and reduces appetite and food intake. In the fasting state, the plasma concentrations of GLP-1 are very low. Levels of circulating GLP-1 rise rapidly after food intake. The GLP-1 meal response depends on ingested nutrients. Carbohydrates are strong stimuli of GLP-1 release. Protein stimulates GLP-1 release, even more than carbohydrates. GLP-1 concentrations also increase after intake of fat, although the elevation is delayed compared to the stimulation of carbohydrates. Dietary fibers may also modify the postprandial GLP-1 response. Therefore, it is essential for us to characterize nutrient compositions of test meals for further studies of meal response of GLP-1.
Other sampling conditions of the meal tests are also needed to be taking care of. GLP-1 is rapidly degraded by the enzyme dipeptidyl peptidase IV (DPP-4). During the meal tests, it is important adding enzyme inhibitors into sampling tubes to avoid hormone degradation. Lugari et al. collected blood samples into tubes containing EDTA and aprotinin during a meal test. They could obtain samples from the same tube for both glucagons and GLP-1 assays. Other study groups reported that samples for GLP-1 needed to be collected into Vacutainer tubes prepared with EDTA and DPP-4 inhibitor for preventing degradation of GLP-1. Another aim of the present study is to compare the differences in GLP-1 concentrations in samples collected by EDTA tubes containing aprotinin or a DPP-4 inhibitor during the meal tests.
Racial differences in GLP-1 levels during oral glucose challenge have been demonstrated recently that severely obese African Americans exhibited lower GLP-1 concentrations than Caucasians. It is worthwhile to examine the meal response of GLP-1 across ethnicities. The current study proposes to observe the GLP-1 response during standardized meal tests in a group of Chinese subjects.
The purpose of the study is to standardize a meal test to facilitate future studies of the postprandial GLP-1 response in Chinese subjects. Eighteen healthy Chinese subjects, aged between 20-65 years old, without history of diabetes, will be recruited for the study. Each subject will receive two mixed meal tests for postprandial GLP-1 excursion at random order: 60 % carbohydrate (CHO)/20 % fat vs. 50 % CHO/30 % fat. The postprandial glucose, insulin, glucagon and other related hormones responses will also be measured. Through the study, we hope to build up a platform for the study of the postprandial GLP-1 response and insulin secretion.
|Study Type :||Observational|
|Actual Enrollment :||21 participants|
|Official Title:||A Pilot Study to Evaluate the Glucagon-Like Peptide 1 Response to the Challenge of Mixed Meals in Chinese Subjects|
|Study Start Date :||April 2009|
|Actual Primary Completion Date :||July 2011|
|Actual Study Completion Date :||July 2011|
- the differences in post-challenge GLP-1 responses between the two meal tests [ Time Frame: 8 months ]
- the correlations of incremental GLP-1 response with insulin sensitivity and insulin secretion indices in each of the meal test [ Time Frame: 8 months ]
Biospecimen Retention: Samples Without DNA
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00884091
|Section of Endocrinology and Metabolism, Department of Medicine, Taipei Veterans General Hospital|
|Taipei, Taiwan, 112|
|Principal Investigator:||Chii-Min Hwu, MD||Taipei Veterans eneral Hospital|