View clinical trials related to Insulin Resistance.
Filter by:The purpose of this study is to determine if pioglitazone is effective in preventing future strokes or heart attacks among non-diabetic persons who have had a recent ischemic stroke.
To study the genetic basis of obstructive sleep apnea using a genealogical approach.
To identify the genes involved in the metabolic syndrome.
To examine the effects of psychological stress on the metabolic syndrome.
The purpose of this study is to investigate the effects of Chromium on glucose tolerance and endothelial function in people at risk for type II diabetes.
This study will examine whether glucosamine affects the way the body responds to insulin. Insulin is a hormone that causes the body to use glucose (sugar). Insulin does not work as well in overweight people, causing a condition called insulin resistance. Insulin also increases the flow of blood into muscle by opening inactive blood vessels. This study will test whether glucosamine, a nutritional supplement that many people take to treat arthritis, can cause or worsen insulin resistance or change how blood vessels react to insulin in normal weight and overweight people. Healthy normal weight and overweight volunteers between 21 and 65 years of age may be eligible for this study. Candidates will be screened with a brief physical examination, medical history, and blood and urine tests. After screening, participants will have three additional outpatient clinic visits for the following procedures: Visit 1 - Glucose clamp test to measure the body's response to insulin: For this procedure, a needle is placed in a vein of each arm, one for drawing blood samples, and one for infusing glucose and a potassium solution. The glucose is infused continuously during this 4-hour test and blood is drawn frequently to monitor glucose and insulin levels. After the test, blood glucose levels are monitored for another 2 hours to make sure they remain at an adequate level to prevent hypoglycemia (low blood sugar). - Blood flow measurement: Blood flow in the brachial artery of the arm is measured to assess how many capillaries (very small blood vessels) are being used to supply nutrients and oxygen to the muscle in the forearm. This test is done at the same time as the glucose clamp test. Blood flow is measured using a technique called contrast ultrasound. A small amount of contrast agent consisting of gas-filled bubbles the size of red blood cells is infused over 10 minutes through one of the catheters placed in the vein for the glucose clamp test. The contrast agent is infused twice, once at the beginning of the glucose clamp test and once at the end of the test. The contrast material creates a signal in response to ultrasound that provides information about the distribution of capillaries in the forearm. - Assignment to medication group: Participants are randomly assigned to take either glucosamine or placebo three times a day by mouth for 6 weeks. At the end of the 6 weeks, no study drug is taken for 1 week, and then participants "cross-over" medications, those who took glucosamine for the first 6 weeks take placebo for the next 6 weeks and vice versa. Visits 2 and 3 For these visits, the glucose clamp test and blood flow measurements are repeated. Visit 2 is scheduled at the end of the first 6-week treatment period, and Visit 3 is scheduled at the end of the second 6-week treatment period.
To evaluate additional cardiovascular risk factors using data from the VA HDL Intervention Trial (VA-HIT).
The purpose of this study is to examine whether the ingestion of the herbal dietary supplement Ginkgo biloba extract has any effect on the efficacy of three classes of diabetic medications - (Glucotrol, Glucophage and Actose). Additionally, the study will examine the effect of Ginkgo biloba extract on pancreatic insulin production in non-diabetic subjects between the ages of 20 and 75 years old.
This pilot study will evaluate the safety and effectiveness of leptin therapy in two children with severe insulin resistance syndrome. Patients with this condition often have high blood sugar levels and may have hormone imbalances, a constant feeling of warmth, fertility problems, large appetite, and enlarged liver due to fat accumulation. Leptin is a hormone produced by fat cells. It influences appetite, affects levels of reproductive hormones, and possibly manages how the body reacts to insufficient food. Certain people with severe insulin resistance syndromes have decreased amounts of fat tissue and make little or no leptin. A 13-year-old male and an 11-year-old female with severe insulin resistance will participate in this study. They will have the following tests and procedures before beginning 4 months of leptin therapy: - Insulin tolerance test - measures blood sugar levels after intravenous (IV) administration of insulin. Blood samples are collected through the IV tube at various intervals during the 1-hour test. - Ultrasound of the liver and, if abnormalities are found, possibly liver biopsies. - Fasting blood tests - to measure blood count, blood lipids, and various hormones and assess liver function. - Resting metabolic rate - to measure the amount of oxygen breathed at rest in order to calculate how many calories are required to maintain resting body functions. - Magnetic resonance imaging of the liver and other organs, and of muscle and fat. - Pelvic ultrasound in female patient - to detect ovarian cysts. - Estimation of body fat - measurements of height, weight, waist, hip size, and skin folds over the arms and abdomen to estimate body fat content. - Oral glucose tolerance test - measures blood sugar and insulin levels. The patient drinks a very sweet drink containing glucose (sugar), after which blood samples are collected through an IV tube in an arm vein at various intervals during the 3-hour test. - Intravenous glucose tolerance test - measures tissue response to insulin and glucose after glucose injection and insulin infusion. Blood is collected over 3 hours to measure insulin and glucose levels. - Appetite level and food intake - to measure hunger level and caloric intake. Patients are questioned about their hunger level, given a variety of foods they may choose to eat and questioned again at various intervals about hunger level. On another day, patients are given breakfast (usually a milkshake) and when they want to eat again, the appetite level and caloric intake study is repeated. - Hormone function tests - the function of three hormones influenced by leptin (corticotropin-releasing hormone, thyrotropin-releasing hormone and luteinizing hormone-releasing hormone) are assessed. The hormones are injected intravenously and then blood samples are drawn. - Questionnaire - patients complete a questionnaire about their activities and how they feel. - 24-hour urine collections - to measure specific hormones, proteins and sugars excreted in the urine. When the above tests are completed, leptin therapy will start. The drug is injected under the skin twice a day for 4 months. Patients will record their symptoms weekly throughout the study. Those with diabetes will measure their blood glucose levels daily before each meal and at bedtime. Follow-up visits at 1, 2 and 4 months after therapy will include a physical examination, blood tests and a meeting with a dietitian. At the 4-month visit, the tests done at the beginning of the study will be repeated.
Several complications have become prevalent in people living with HIV/AIDS, including increased blood sugar, increased blood fats and cholesterol, and fat tissue redistribution. The causes of these complications are not well understood and effective treatments have not been identified. We propose to test the efficacy and safety of 2 treatments for these complications in people living with HIV/AIDS: aerobic, weight lifting exercise training, and a new insulin-sensitizing agent called rosiglitazone (Avandia). Exercise and rosiglitazone have been effective and moderately safe when used in HIV-seronegative people with diabetes, but a specific trial is needed to test efficacy and safety in people living with HIV/AIDS.