Dopamine and Insulin Resistance

Obesity Clinical Trial

Official title:

Dopamine and Insulin Resistance

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00802204
• Other study ID #: IRB#080861 and 061246
• Status: Completed
• Phase: N/A
• First received: December 2, 2008
• Last updated: December 12, 2015
• Start date: December 2008
• Est. completion date: December 2012

Study information

• Verified date: February 2011
• Source: Vanderbilt University
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Food and Drug Administration
• Study type: Interventional

Clinical Trial Summary

Obese individuals have fewer striatal dopamine type 2 receptors (DRD2) than normal weight individuals. Lower DRD2 levels are associated with addiction and a decreased sense of pleasure.Obesity is also associated with insulin resistance (poor insulin action).We propose that insulin resistance and low DRD2 are associated. Using PET imaging,we aim to determine DRD2 binding potential (BP) in the brain is associated with insulin resistance and neuroendocrine hormone levels. Obese participants will be compared to lean, gender and age similar participants. We also aim to determine the effect of caloric restriction on DRD2 BP in obese subjects

Recruitment information / eligibility

• Status: Completed
• Enrollment: 40
• Est. completion date: December 2012
• Est. primary completion date: April 2011
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 18 Years to 60 Years

Eligibility

Inclusion Criteria:

• Ages 18-60 yrs

• obese BMI > 30kg/m2 and Weight less than 350 lbs

• lean control BMI 18-25kg/m2

Exclusion Criteria:

• Structured exercise > equivalent to 30mins 5x week of walking times a week

• History of Substance Abuse, including but exclusive to alcohol, cocaine, marijuana, heroin, nicotine

• Current psychiatric disorder or significant h/o disorder

• Use or any antidepressants or antipsychotics for last 3-6months or depot antipsychotics in the last 12 months

• Any condition felt by PI or co-investigators to interfere with ability to complete the study

• Inability to abstain from alcohol, physical exercise or > 1 cup of coffee or equivalent daily for 3 days prior to imaging studies

• Significant co-morbidities including atherosclerotic disease, metabolic disease, liver or renal insufficiency or abnormality found on MRI

• Any condition which would interfere with MRI or PET studies, e.g. claustrophobia, cochlear implant, metal fragments in eyes, cardiac pacemaker, neural stimulator, tattoos with iron pigment and metallic body inclusions or other metal implanted in the body which may interfere with MRI scanning

• Subjects on medications determined by PI, ex. sibutramine, frequent benzodiazepines or related drugs, which could affect quality of study for last 3 months.

Study Design

Intervention Model: Single Group Assignment, Masking: Open Label

Related Conditions & MeSH terms

• Insulin Resistance
• Obesity

Intervention

Radiation:
• PET scan
Subjects will undergo a PET scan of the brain using the radioligand,fallypride [18F]. Obese subjects who complete caloric restriction will have repeat scan after diet.

Procedure:
• Oral glucose tolerance test
Subjects will be required to drink a glucose solution; blood samples will be taken over a 5-hour time period
• MRI
An MRI of the brain and abdomen will be performed prior to PET scan

Behavioral:
• Psychological scales to assess attitudes and behaviors related to eating and quality of life
A series of short psychological scales will be administered during the study.

Other:
• Caloric Restriction
Obese participants will go a shortterm very low calorie diet

Locations

Country	Name	City	State
United States	Vanderbilt University Medical Center	Nashville	Tennessee

Sponsors (1)

Lead Sponsor	Collaborator
Vanderbilt University

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Are fasting neuroendocrine hormones and insulin sensitivity associated with DRD2 receptor binding?		Day of study	No
Secondary	Are certain eating behaviors associated with DRD2 binding?		Day of study	No
Secondary	Does caloric restriction alter DRD2 DP in obese participants?		Day of study	No