Integrating the Genetic and Metabolic Faces of Obesity

Phase 1

Completed

• Conditions: Insulin Resistance; Obesity; Metabolic Syndrome
• Interventions: Drug: thiazolidinedione; Behavioral: weight loss

• Registration Number: NCT00285844
• Lead Sponsor: Stanford University

Brief Summary

The goal of this study is to determine why some obese individuals develop insulin resistance and others do not. We hypothesize that an impairment in differentiation of fat cells (adipocytes) is responsible for the development of insulin resistance in select obese individuals. This study will evaluate obese individuals at baseline with respect to characteristics of adipocytes, including gene expression, and will then entail randomizing subjects to either weight loss or treatment with an insulin sensitizing drug (pioglitazone). Changes in insulin resistance will be associated with changes in adipocyte morphology and gene expression.

Detailed Description

Healthy overweight/obese individuals will be screened for insulin resistance. Both insulin resistant individuals and insulin sensitive individuals (to serve as controls) will be eligible to enroll. Fat cel biopsy and CT scan of the abdomen is required at baseline and after an intervention with either weight loss or pioglitazone (drug to improve insulin resistance). Subjects will repeat insulin resistance test after the intervention as well. Subjects will learn much about their metabolism in this study, and will have an opportunity to improve their insulin resistance.

Study Timeline

• Study Start: 2005-10
• Study First Submitted: 2006-01-31
• Study First Submitted QC: 2006-01-31
• Study First Posted: 2006-02-02
• Primary Completion: 2012-10
• Study Completion: 2012-10
• Status Verified: 2024-12
• Last Update Submitted: 2024-12-02
• Last Update Posted: 2024-12-04

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 88

Inclusion Criteria

• nondiabetic defined as fasting plasma glucose < 126 mg/dL
• body mass index 27 to 35 kg/m2
• no major organ diseases
• able to come to Stanford for regular clinical research center visits
• English speaking or has own translator

Exclusion Criteria

• pregnancy/lactation
• history of eating disorder or major psychiatric illness
• allergy to thiazolidinedione
• elevation of liver enzymes (> 2.5 times upper normal limit)

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
pioglitazone	thiazolidinedione	IR and IS subjects will be randomized to pioglitazone 45 mg daily for 16 wks for comparison with dietary weight loss intervention
Dietary Weight Loss	weight loss	IR and IS subjects will be randomized to dietary weight loss for 16 wks for comparison to pioglitazone intervention

Primary Outcome Measures

Name	Time	Method
Adipose Cell Size Distribution	2005-2012

Secondary Outcome Measures

Name	Time	Method
Adipose Tissue Gene Expression	2005-2013

Trial Locations

Locations (1)

Stanford University; 🇺🇸 Stanford, California, United States