Project Number: 1950-51000-072-01-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Jan 1, 2009
End Date: Dec 31, 2013
1. To determine the effect of altering dietary composition by restricting carbohydrates, fats, glycemic load, or total calories on plasma lipoproteins, blood pressure, glucose homeostasis, and body weight, cardiovascular risk factors in overweight and obese subjects under controlled feeding conditions and in the freeliving state. 2. Develop and test an interactive program to provide an optimal diet and exercise program for middle-aged and elderly overweight and obese subjects for weight loss and heart disease reduction. 3. Observe the interactions of nutritional factors, especially intake of calories, types of fat, types of carbohydrate, level of physical activity, and different genetic factors on lipoprotein subspecies, obesity, metabolic syndrome, inflammatory markers, and heart disease risk in overweight and obese subjects and subjects with premature cardiovascular disease as compared to age- and gender-matched control subjects within populations. 4. Determine the in vitro and in vivo effects of dietary fatty acids, cholesterol, carbohydrates, hormone levels, hormonal replacement, B vitamins, cholesterol biosynthesis inhibition and cholesteryl ester transfer protein inhibition on lipoprotein metabolism and gene expression, and inflammation in human liver cells (HepG2) and in human subjects under metabolic ward conditions using stable isotopes.
In the next 5 years the Lipid Metabolism Laboratory will continue to test optimal lifestyle strategies for the prevention of coronary heart disease (CHD). Human intervention studies will assess effects of supplementation with omega 3 fatty acids and plant sterols versus placebo on CHD risk factors, caloric restriction in older overweight subjects using diet either low or high in glycemic load on CHD risk factors, and an aggressive lifestyle and omega 3 fatty acid supplementation program in overweight subjects with CHD versus usual care on CHD risk factors, cognitive function, and change in coronary atheroma. Population studies will examine the interaction of diet as assessed by questionnaires, genetics as assessed by genotyping, and biochemical markers of insulin resistance, inflammation, and alterations in lipoprotein particles on CHD risk and cognitive decline in participants in the Framingham Heart Study (original cohort and offspring). Human metabolic studies will examine the effects of diets low in animal fat and cholesterol with or without fish versus average American diets on lipoprotein metabolism. We will also examine the effects of estrogens and niacin on human plasma lipoprotein metabolism. Cell studies will examine the mechanisms of action of different fatty acids on the expression of specific genes involved in reverse cholesterol transport in human liver cells and in macrophages. Our overall objectives are to develop optimal lifestyle strategies for the prevention of CHD.