Ghrelin Regulation and Structure: Effect of Thiazolidinedione Therapy on Ghrelin
The purpose of this study is to learn more about how insulin resistance (inability to process glucose correctly resulting in mildly elevated glucose levels) affects the hormone ghrelin.
|Study Design:||Allocation: Randomized
Endpoint Classification: Pharmacokinetics/Dynamics Study
Intervention Model: Crossover Assignment
Masking: Single Blind (Subject)
Primary Purpose: Basic Science
|Official Title:||Ghrelin Regulation and Structure: Effect of Thiazolidinedione Therapy on Ghrelin|
- The primary outcome of this study will be the comparison of ghrelin suppressibility (total and acylated) in response to meals obese subjects before and after 3-months therapy with a thiazolidinedione. [ Time Frame: 0 and 3 months ] [ Designated as safety issue: No ]
- Secondary outcomes for this aim include the degree of insulin suppressibility as measured by a hyperinsulinemic-euglycemic clamp. [ Time Frame: 3 months ] [ Designated as safety issue: No ]
- Secondary outcome for this aim include the degree of insulin suppressibility as measured by an area-under-the-curve measurements during the 12½ hours of meal testing for ghrelin, glucose,insulin and gut-peptides. [ Time Frame: 3 months ] [ Designated as safety issue: No ]
|Study Start Date:||February 2009|
|Study Completion Date:||May 2011|
|Primary Completion Date:||May 2011 (Final data collection date for primary outcome measure)|
Placebo Comparator: Placebo
Treatment with placebo for 3 months before spectroscopy, hyperinsulinemic-euglycemic clamp, control diet, blood sampling.
treatment with placebo for 3 months
Other Name: placebo
Active Comparator: 2
Treatment with pioglitazone for 3 months before hyperinsulinemic-euglycemic clamp, control diet with blood sampling and spectroscopy.
treatment with 30mg daily for two weeks then 45mg every day with pioglitazone for three months
Other Name: thiazolidinedione therapy
Insulin resistance suppresses fasting ghrelin levels and impairs postprandial ghrelin suppression. Improved insulin sensitivity with a thiazolidinedione will raise ghrelin levels, enhance meal-related suppression, but not change the ratio of total to active ghrelin or result in an alteration of ghrelin structure.
|United States, Oregon|
|Oregon Health & Science University|
|Portland, Oregon, United States, 97239|
|Principal Investigator:||Jonathan Q. Purnell, M.D.||Oregon Health and Science University|