View clinical trials related to Insulin Resistance.
Filter by:Obesity and type 2 diabetes are occurring at epidemic rates in the United States and worldwide. The global burden of diabetes is estimated to double over the next 25 years. Obese children are at risk for the development of insulin resistance, relative insulin deficiency and type 2 diabetes mellitus (DM). The prevention of type 2 DM is hindered by the lack of a non-invasive predictive test, knowledge as to individual risk and effective preventative measures. There is increasing evidence that alterations in mitochondria contribute to the development of diabetes in humans. Therefore, it is important to explore mitochondrial dysfunction as a potential predictor of diabetes in children and a potential target for prevention. The aims of the proposed protocol are to determine whether an intensive exercise intervention can improve mitochondrial function in children identified as having mitochondrial dysfunction and insulin resistance. The use of a non-invasive imaging technique will allow for a functional in vivo assessment of mitochondrial activity. The investigators propose the investigation of an intensive exercise protocol designed to improve mitochondrial function in children who are insulin resistant and have documented mitochondrial dysfunction by magnetic resonance spectroscopy. The study is designed to investigate the plasticity of abnormal mitochondrial function in high risk children. In summary, the proposed projects will investigate mitochondrial function as a non-invasive predictive marker for the development of insulin resistance and type 2 diabetes mellitus in children and attempt to modify mitochondrial function with an intensive exercise intervention. The study of mitochondrial dysfunction in children may both identify those at risk for disease and provide a molecular therapeutic target for prevention and treatment. The investigators hypothesize that children with insulin resistance and mitochondrial dysfunction who are randomized to intensive exercise versus standard lifestyle advice will show improvement in mitochondrial function and insulin sensitivity.
Hypothesis: Insulin-resistant African-American and Hispanic adolescents will show significant improvement of insulin sensitivity (SI) and positive changes associated with fibrinolytic markers and lipid profile after a two month supervised aerobic training.
In the United States cardiovascular disease (CVD) accounts for 1 in every 2.8 deaths and is the leading cause of death among men and women 65 years or older (1). Studies have shown that the risk for cardiovascular disease is higher in individuals with the Metabolic Syndrome (2). Metabolic Syndrome (MBS) is defined by the Adult Treatment Panel III (ATP III) guidelines as a group of risk factors that includes 3 or more of the following: abdominal obesity, hypertriglyceridemia, low high-density lipoprotein (HDL) cholesterol, high blood pressure, and high fasting glucose (3). These factors place individuals at increased risk for the development of both cardiovascular disease (CVD) and diabetes mellitus (3). It is commonly held that insulin resistance is the driving force for the development of the MBS. Although there is a significant increase in incidence of MBS in the elderly, there are few studies that specifically examined MBS in that population. The prevailing opinion is that the strikingly high prevalence of the MBS in the elderly is due to concurrent obesity - i.e., the population gains weight as it ages, and development of the MBS accompanies the weight gain. However, while it is true that becoming obese may decrease insulin sensitivity, it has also been demonstrated that not all obese individuals are insulin resistant. Some studies suggest that up to 40% of obese individuals demonstrate normal insulin sensitivity (4). In addition, it is notable that the rate of increasing MBS in the population exceeds that of the rate of increasing BMI, suggesting that, while BMI may be a modulating factor, another factor independent of obesity also contributes to the development of MBS in the elderly. It is the investigators hypothesize that the MBS in the obese elderly population is primarily linked to insulin resistance and not to obesity per se. The investigators propose to test this hypothesis by assessing MBS and insulin resistance in a population of obese elderly men and women and then determining whether or not the MBS tracks with insulin resistance.
In this study we hypothesize that blocking the angiotensin II AT1-receptor improves the insulin-induced microvascular dilatation. Objectives: 1. Does blockade of the angiotensin II AT1-receptor improve the insulin-induced microvascular effects in hypertensive patients. 2. Does blockade of the angiotensin II AT1-receptor impair the insulin-induced microvascular effects in normotensive control subjects?
The goal of this research study is to study the effect of testosterone or estrogen on blood sugar control and fat metabolism. Changes in hormone levels with age may affect risk factors for heart disease such as diabetes. Diabetes is a glandular condition associated with lack of the hormone insulin or an insensitivity to it resulting in problems with blood sugar control and fat metabolism. The effect of commonly used hormonal supplements such as testosterone by older adults on insulin and body composition is not well understood. In this study, the role of testosterone and estrogen on your ability to control blood sugar and your body composition will be assessed. We plan to study 60 subjects. All of these subjects will be healthy older men between the ages of 60-85 years old who are not on testosterone therapy. Subjects that are screened who have any clinically significant abnormalities detected on their screening physical exam or laboratory testing (e.g. PSA > 4), who have a history of prostate cancer, polycythemia, or who cannot take testosterone will not be included. If a subject is eligible to participate after initial screening, that subject will take medications to adjust their hormone levels and have tests performed that measure insulin sensitivity and adiposity before and after these hormone medications. The outcomes that will be measured are: 1) insulin sensitivity, 2) hormone levels (total and free testosterone levels, sex hormone-binding globulin levels) and 3) body composition and abdominal adiposity.
The prevalence of pediatric obesity is increasing at an unprecedented rate. Obese children are at risk for the development of insulin resistance, relative insulin deficiency and type 2 diabetes mellitus. However, the cause of insulin resistance remains an area of scientific interest. The study of type 2 diabetes in children is limited by the lack of a non-invasive method to evaluate insulin resistance. Recent studies have suggested that mitochondrial dysfunction is associated with, and perhaps predictive of insulin resistance in adult relatives of individuals with type 2 diabetes. Mitochondria generate energy in muscle tissue through the production of ATP, and are important in the metabolism of both glucose and fat. This study evaluates a novel, non invasive, safe method for predicting insulin resistance and diabetes in children using a magnetic resonance imaging (MRI) based technique to measure mitochondrial function. We propose to investigate mitochondrial function and glucose metabolism in obese and non-obese children in early, mid and late puberty. Analyses will be conducted to investigate the presence of mitochondrial dysfunction in obese children, to evaluate the contribution of mitochondrial dysfunction to insulin resistance, and to determine the contribution of pubertal status to mitochondrial dysfunction and insulin resistance. The successful completion of this study would provide evidence to support the hypothesis that mitochondrial dysfunction plays a role in insulin resistance and diabetes in children. In addition, it would provide a new technique for the prediction of disease states and perhaps lead to the development of preventative therapeutics for insulin resistance and type 2 diabetes in children. We hypothesize that mitochondrial dysfunction will mirror the progression of insulin resistance and precede and predict abnormal glucose metabolism in a population with pediatric obesity
The Metabolic Syndrome (MS) is prevalent in the American population and is strongly associated with premature coronary disease. Lifestyle intervention, primarily exercise and dietary changes, are foundational treatment strategies for independent components of MS, but these interventions have not been thoroughly evaluated in MS. Even with very modest weight loss, in the setting of caloric restriction and exercise, marked improvement MS parameters have been noted. However, it is not known whether it is diet with weight loss or exercise that improves the metabolic derangements associated with MS. We propose a study designed to examine the relative impact of diet or exercise on the components of MS. Furthermore, it is known that psychological factors significantly impact the ability of patients to initiate and sustain lifestyle changes. We will monitor certain psychological states to evaluate their impact on the success of weight loss and sustainability of lifestyle changes throughout this study. Specific Aims: 1.) Evaluate the relative efficacy of diet with weight loss or exercise on improving the markers of metabolic syndrome. 2.) Determine of pre-existing psychological factors influence the effectiveness of diet with weight loss or exercise on the markers of metabolic syndrome. Design: Adult women (> 18 yrs) with a body-mass index (BMI) 30 kg/m2 will be assessed for MS and randomized to one of three groups (n = 34/group), Control (C), diet with weight loss alone (D), or exercise alone (E). The intervention groups will participate in supervised dietary changes designed for weight loss or exercise for 6 months. Anthropomorphic, serologic, and psychological parameters will be monitored and compared using ANOVA. Hypothesis: As indexed by the improvement in the laboratory markers of the components of metabolic syndrome, exercise alone has a more profound positive impact on Metabolic Syndrome then diet with weight loss alone.
Study Description: Patients with mutations of the insulin receptor have diabetes that is challenging to control with conventional therapies, leading to early morbidity and mortality. We hypothesize that recombinant leptin (metreleptin) in these patients will improve glycemia control. Objectives: Primary Objective: To determine if 1 year of metreleptin will improve glycemia control in patients with genetic defects of the insulin receptor. Secondary Objectives: To determine mechanisms by which metreleptin improves glycemia. Endpoints: Primary Endpoint: Hemoglobin A1c. Secondary Endpoints: fasting plasma glucose, fasting insulin/C-peptide, glucose/insulin/C-peptide area under the curve during oral glucose tolerance test. Study Population: 20 male or female patients with mutations of the insulin receptor, age (Bullet)5 years, at the NIH Clinical Center. Description of Sites/Facilities Enrolling Participants: Description of Study Intervention: NIH Clinical Center Open label study of metreleptin, 0.2 mg/kg/day (max dose 0.24 mg/kg/day).