Clinical trial NCT00830999: Fat Metabolism in Response to Acute Diet- and Exercise-induced Changes in Energy Balance
Official title: VLDL-triglyceride Metabolism in Response to Acute Diet- and Exercise-induced Changes in Energy Balance
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Cardiovascular Diseases
Keywords: fat metabolism
exercise
liver
lipoproteins
triglycerides
Lead sponsor: Washington University School of Medicine
Sponsor class: OTHER
First posted: 2009-01-28
Enrollment: 12
Sex: MALE
Minimum age (years): 21
Maximum age (years): 50
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: SINGLE_GROUP
Primary purpose: PREVENTION

Brief summary: This study is being conducted to learn more about the role of diet and exercise in regulating plasma triglyceride (fat) metabolism. The investigators will examine the effect of acute (24 hour) changes in energy intake and expenditure on fat metabolism the following day.

Detailed description: Excess body fat and a sedentary lifestyle are associated with increased plasma triglyceride (TG) and apolipoprotein B-100 (apoB-100) concentrations, which are important risk factors for the development of cardiovascular disease.

Weight loss and endurance exercise improve plasma lipid and lipoprotein concentrations. However, the mechanisms responsible for this effect are largely unknown, and much uncertainty remains regarding the independent roles of dietary energy intake, exercise energy expenditure, and net energy balance in controlling plasma TG concentrations.

The main goal of this project, therefore, is to investigate the mechanisms by which acute alterations in energy balance, induced by diet and/or physical activity (endurance exercise), regulate very-low density lipoprotein (VLDL) metabolism.

Subjects will be asked to perform 3 separate trials. One of these will always be an "energy balance" trial that will act as the control trial for the other 2 trials they perform. Subjects will therefore be randomized to 2 different study arms.

Eligibility criteria: Inclusion Criteria:

* overweight and obese men
* normal to mild hypertriglyceridemia

Exclusion Criteria:

* Smoking
* Any medical condition other than increased body weight (e.g. diabetes, heart disease, etc.).
* Use of drugs known to affect lipid metabolism (e.g. statins, etc.).
* Regular exercise training.

Primary outcomes:
measure: Very Low Density Lipoprotein-Triglyceride and apoB-100 concentrations
timeFrame: After acute (24 hour) changes in energy intake and/or energy expenditure
Secondary outcomes:
measure: Liver Very Low Density Lipoprotein-Triglyceride and apoB-100 secretion rates
timeFrame: After acute (24 hour) changes in energy intake and/or energy expenditure
measure: Liver Very Low Density Lipoprotein-Triglyceride and apoB-100 clearance rates from plasma
timeFrame: After acute (24 hour) changes in energy intake and/or energy expenditure
measure: Plasma glucose concentration and turnover rate
timeFrame: After acute (24 hour) changes in energy intake and/or energy expenditure
measure: Plasma insulin concentration
timeFrame: After acute (24 hour) changes in energy intake and/or energy expenditure
measure: Plasma free fatty acid concentration and turnover rate
timeFrame: After acute (24 hour) changes in energy intake and/or energy expenditure
measure: Plasma glucose concentration
timeFrame: During acute (24 hour) changes in energy intake and/or energy expenditure
measure: Plasma insulin concentration
timeFrame: During acute (24 hour) changes in energy intake and/or energy expenditure
measure: Plasma free fatty acid concentration
timeFrame: During acute (24 hour) changes in energy intake and/or energy expenditure
Other outcomes:
Locations:
city: Saint Louis
country: United States
facility: Washington University in Saint Louis
state: Missouri
Study officials:
affiliation: Washington University School of Medicine
name: Bettina Mittendorfer, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Smith GI, Magkos F, Reeds DN, Okunade AL, Patterson BW, Mittendorfer B. One day of mixed meal overfeeding reduces hepatic insulin sensitivity and increases VLDL particle but not VLDL-triglyceride secretion in overweight and obese men. J Clin Endocrinol Metab. 2013 Aug;98(8):3454-62. doi: 10.1210/jc.2013-1786. Epub 2013 Jun 7.