Fat Cell Size and Overfeeding

This study is ongoing, but not recruiting participants.
Sponsor:
Collaborator:
Information provided by (Responsible Party):
Eric Ravussin, Pennington Biomedical Research Center
ClinicalTrials.gov Identifier:
NCT01672632
First received: August 20, 2012
Last updated: November 26, 2013
Last verified: November 2013
  Purpose

It has been shown that large fat cells are associated with more risks for insulin resistance and more cardiovascular risk factors such as high cholesterol or triglycerides.


Condition Intervention
Over Eating
Other: Overfeeding

Study Type: Interventional
Study Design: Intervention Model: Single Group Assignment
Masking: Open Label
Official Title: Fat Cell Size and Overfeeding and Etopic Study

Resource links provided by NLM:


Further study details as provided by Pennington Biomedical Research Center:

Primary Outcome Measures:
  • Determine the effect of 8-weeks 40% high fat overfeeding in 40 healthy, young adults on adipose and skeletal muscle characteristics, ectopic fat accumulation, insulin sensitivity, and metabolic flexibility. [ Time Frame: 10 months ] [ Designated as safety issue: No ]
    This study will investigate how fat cell size (independent of total fat mass) affects metabolic outcomes of overfeeding, including changes in fat deposition, insulin sensitivity and muscle oxidative capacity. It has been shown that large fat cells relative to fat mass are associated with higher risks for insulin resistance and type 2 diabetes.


Secondary Outcome Measures:
  • Fat Deposition [ Time Frame: 10 Months ] [ Designated as safety issue: No ]
    Viewing of adipose tissue or body fat and skeletal muscle characteristics over a period.

  • Insulin Sensitivity [ Time Frame: 10 months ] [ Designated as safety issue: No ]
    Measure and monitor the natural hormone insulin becomes less effective at lowering blood sugars. The resulting increase in blood glucose may raise levels outside the normal range and cause adverse heealth effects, depending on dietary conditions or sensitivity of cells to insulin.

  • Muscle Oxidative Capacity [ Time Frame: 10 Months ] [ Designated as safety issue: No ]
    A measure of a muscle's maximal capacity to use oxygen in microliters of oxygen consumed per gram of muscle per hour.

  • Circadian Blood Pressure variability [ Time Frame: 10 Months ] [ Designated as safety issue: No ]
    Blood pressure and heart rate measurement: An automatic BP monitoring device (Mortara® Ambulo 2400) for ambulatory use was attached to a BP cuff to obtain blood pressure (BP) and heart rate (HR) readings at 30-min intervals during the day (6:30 AM to 9:30 PM) and 60-min intervals at night (10 PM to 6 AM) while the participants went about their activities. Data were downloaded into the database at the end of the 7-day recording span for a chronobiological analysis. This was done at baseline, post-overfeeding and at 3 months.

  • Resting Endothelial function testing [ Time Frame: 10 Months ] [ Designated as safety issue: No ]
    Endothelial function testing: Assessment of resting endothelial function was done with the participant in a fasting state, after having avoided stimulants (caffeine, tobacco, alcohol, exercise) for 12 hours, at the same fixed clock hour (range 8-10 AM), using the EndoPAT 2000 device manufactured by ITAMAR Medical®.


Enrollment: 40
Study Start Date: May 2008
Estimated Study Completion Date: May 2014
Primary Completion Date: May 2012 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Overfeeding
We overfed 40 young, healthy adults by 40% of their baseline energy requirements for 8 weeks. The diet consisted of 41% carbohydrate, 44% fat, and 15% protein.
Other: Overfeeding
We overfed 40 young, healthy adults by 40% of their baseline energy requirements for 8 weeks. The diet consisted of 41% carbohydrate, 44% fat, and 15% protein.

Detailed Description:

This study will look at fat cell size and how it affects fat deposition, insulin resistance and muscle oxidative capacity. A comparison will be made with the differences between participants with larger versus smaller fat cells in insulin resistance and blood levels of lipids. The study will also determine if characteristics of fat cells and muscle can predict the development of weight gain-induced insulin resistance.

  Eligibility

Ages Eligible for Study:   18 Years to 40 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Your Body Mass Index (height to weight ratio) is 22.5 to 32.5 (inclusive).
  • You are 18-40 years of age.
  • You are willing to enroll in an 8 week overfeeding study causing a 5-8 % weight gain.
  • You are willing to eat all your meals from Pennington and only meals from Pennington for approximately 10 weeks total, even when you are full. Prior to overfeeding 2 Meals per day will be served at Pennington with lunch packed for at least 7 days. After that time participants will receive and eat all (overfeeding) meals at PBRC for 8 weeks. Post-overfeeding will consists of weight-maintenance diet for 1 week. All meals will be monitored at Pennington.
  • You are willing to maintain the same level of exercise after enrollment in the study throughout the length of the study.
  • You are willing to complete nutritional and activity questionnaires.

Exclusion Criteria:

  • You weight > 300 lbs
  • You have a history of cardiovascular disease or diabetes.
  • You have a fasting blood glucose > 110 mg/dL.
  • You have an average screening blood pressure > 140/90.
  • You have liver disease.
  • You have thyroid disease.
  • Have Acid Reflux
  • Had cancer in the last 5 years (Some skin cancers OK)
  • Have HIV
  • Have had an Eating Disorders
  • You are pregnant or breastfeeding.
  • You have gained or lost more than 3kg in the last 3 months
  • You require chronic use of medications including diuretics, steroids and adrenergic-stimulating agents.
  • You or a member of your family has a history of blood clots (deep vein thrombosis or pulmonary embolism)
  • You have poor circulation, history of bypass operation in your legs, blood coagulation disorders, diagnosed peripheral arterial or vascular disease, cramping pain in your leg muscle during exercise or nerve damage to your legs
  • You have varicose veins (per discretion of MD or NP)
  • You have had previous GI surgery, obstructive disease of the GI tract, hyper motility disorder or a history of problems of impairment of the gag reflex.
  • You have emotional problems such as clinical depression or other diagnosed psychological conditions.
  • You are claustrophobic.
  • You have metal objects in your body such as implanted rods or surgical clips or magnetic objects that are incompatible with the MRI/MRS.
  • You smoke or use tobacco products
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01672632

Locations
United States, Louisiana
Pennington Biomedical Research Center
Baton Rouge, Louisiana, United States, 70808
Sponsors and Collaborators
Pennington Biomedical Research Center
Investigators
Principal Investigator: Eric Ravussin, PhD Pennington Biomedical Research Center
Principal Investigator: Alok Gupta, MD Pennington Biomedial Research Center
  More Information

No publications provided by Pennington Biomedical Research Center

Additional publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: Eric Ravussin, Principal Investigator, Pennington Biomedical Research Center
ClinicalTrials.gov Identifier: NCT01672632     History of Changes
Other Study ID Numbers: EAT PBRC26040
Study First Received: August 20, 2012
Last Updated: November 26, 2013
Health Authority: United States: Institutional Review Board

Additional relevant MeSH terms:
Hyperphagia
Signs and Symptoms, Digestive
Signs and Symptoms

ClinicalTrials.gov processed this record on July 23, 2014