View clinical trials related to Hypercholesterolemia.
Filter by:OBJECTIVES: I. Develop an approach for treating patients with homozygous familial hypercholesterolemia using gene therapy with autologous hepatocytes transduced with a normal low-density lipoprotein receptor gene.
OBJECTIVES: I. Identify the genetic defect and fine map the gene that causes sitosterolemia.
Nitric oxide (NO) is a soluble gas, continuously synthesized by the endothelium, that contributes importantly to vasodilator tone of the coronary and systemic circulations by activating guanylyl cyclase in vascular smooth muscle, causing relaxation. Although regional synthesis of NO by the endothelium contributes to local vasodilator tone, Stamler and co-workers have proposed that regional vascular tone may also be regulated by NO transported from the lungs by hemoglobin as a consequence of enhanced binding of NO to reactive thiols of oxygenated hemoglobin. This study is designed to determine the contribution of hemoglobin-transported NO to forearm microvascular dilator tone in healthy subjects at rest and during regional hypoxia associated with forearm exercise stress, with measurements made before and after regional blockade of endothelial NO synthesis. Findings in this study may be relevant to understanding the physiological contribution and therapeutic potential of hemoglobin-transported NO in the regulation of vasodilator tone in diseases and conditions associated with regional endothelial dysfunction and reduced endothelial NO bioactivity (e.g., hypertension, diabetes mellitus, hypercholesterolemia, cigarette smoking, and estrogen deficiency).
Estrogen therapy has been associated with reduced risk of coronary heart disease events in observational studies of postmenopausal women. Although favorable effects of estrogen on lipoprotein cholesterol levels probably account for much of this benefit, direct vascular effects (vasomotor, hemostatic, anti-inflammatory) regulated by nitric oxide (NO) may also be of importance. We have recently shown that vasodilator effects of estrogen in the coronary circulation are due to enhanced bioactivity of NO released from the endothelium. Estrogen has been shown to stimulate synthesis and activity of the enzyme NO synthase with enhanced NO synthesis in endothelial cells in culture. Because L-arginine is the natural substrate for the enzyme NO synthase, we propose that the combination of L-arginine and estrogen might have additive vasomotor, hemostatic and anti-inflammatory effects in hypercholesterolemic postmenopausal women.
A layer of cells called the endothelium line the walls of blood vessels. These cells produce substances that control the tone of blood vessels and thus control blood flow through the vessel. This regulating activity of the endothelium is dysfunctional in several diseases of the heart and blood vessels, including high blood pressure and high levels of cholesterol. Previous research has pointed toward a decrease in the action of nitric oxide (NO) as the cause of this abnormality. Nitric oxide is a substance produced by the cells of the endothelium that plays a role in the relaxation of blood vessels. In this project researchers plan to study blood flow through the blood vessels in patients forearms after receiving four different drugs: sodium nitroprusside, acetylcholine, L-NMMA, and aspirin. These four drugs act on the blood vessels of the forearm through different mechanisms. Acetylcholine and sodium nitroprusside are drugs that open the blood vessels of the forearm and increase blood flow through the vessel. L-NMMA is a drug that blocks production of nitric oxide (NO). Aspirin's role in controlling blood flow is unknown. Patients participating in this research study will not directly benefit from it. However, the study will contribute to researchers understanding of diseases of the blood vessels and heart.
A layer of cells called the endothelium line the walls of blood vessels. These cells produce substances that control the tone of blood vessels and thus control blood flow through the vessel. One of the substances produced involved in the control of blood vessel function is nitric oxide. Nitric oxide (NO) plays a role in the relaxation of blood vessels. Researchers have been interested in the function of the endothelium in patients with high blood pressure (essential hypertension) and patients with high cholesterol (hypercholesterolemia). After conducting studies on the endothelium and nitric oxide, researchers have found that the endothelium is indeed functioning abnormally in patients with high blood pressure and high cholesterol. In addition, researchers have determined that the dysfunction is a result of abnormalities in the nitric oxide (NO) system. In this study researchers plan to investigate the relationship between blood vessel responses in real-life settings versus laboratory settings in normal volunteers, patients with high blood pressure, and patients with high cholesterol.
Early studies have shown that the immune system may play a role in the development of strokes. Conditions such as high blood pressure, high cholesterol, diabetes, and old age can activate the immune system and increase the risk of developing hardening of the arteries (atherosclerosis) and damaged blood vessels. Researchers will attempt to characterize factors that may contribute to atherosclerosis and stroke by measuring certain components of the immune system, cytokines and leukocyte activation. Measurements will be taken from patients that are considered to be stroke prone and from patients without risk factors for the development of stroke. Researchers will measure the immune system components at the beginning of the study, at six months, and at the one-year completion of the study. The study will attempt to determine; I) If patients with risk factors for stroke have an increased activation of the immune system II) If patients with risk factors for stroke that are symptomatic have higher levels of immune system activation compared to patients who do not have symptoms III) If patients with increased activation of the immune system have accelerated hardening of the arteries (atherosclerosis)
Homozygous familial hypercholesterolemia is a rare inherited disease of metabolism. It occurs in less than 1 in 1 million people within the United States. Patients with the disease are typically children and young adults who develop heart disease early in life. Children less than age 5 years with this disease have suffered heart attacks and death. The normal process that removes cholesterol particles from the blood stream does not work in patients with this disease. It causes cholesterol to build-up in the arteries and leads to hardening of the arteries (atherosclerosis). The goal of this study is to detect and measure atherosclerosis in these patients before it becomes permanent and potentially life threatening. Patients with this disease can participate in this study. Researchers plan to evaluate patients with homozygous familial hypercholesterolemia using new and standard methods for detecting atherosclerosis. Researchers plan to use information gathered during this study to develop new, promising treatments such as liver transplantation and gene therapy.
Researchers plan to study the fat-rich particles, called lipoproteins, which circulate in the blood. This study is designed to improve understanding of normal, as well as abnormal, lipoprotein metabolism and the role it plays in the development of hardening of the arteries (atherosclerosis). Patients participating in this study will receive injections of lipoproteins or apolipoproteins (the protein component of lipoproteins) that have been isolated and purified. These lipoproteins will be labeled with small amounts of radioactive material and sterilized before they are injected into the patient. Patients participating in the study will be required to have blood samples taken, and provide urine samples throughout the course of the study. In addition, patient will be required to follow a specially formulated diet. Patients will be weighed throughout the course of the study.
The purpose of this study is to prevent major cardiovascular events (heart attack, stroke, or cardiovascular death) in adults with type 2 diabetes mellitus using intensive glycemic control, intensive blood pressure control, and multiple lipid management.