Active clinical trials for "Insulin Resistance"

The aim of this study is to evaluate the effects of three dominant dietary patterns - conventional low-fat, low-glycemic index (GI) and very-low-carbohydrate - on energy metabolism and heart disease risk factors following weight loss in obese young adults in a feeding study

The purpose of the study is to evaluate the change in insulin sensitivity and secretion indices (early markers for development of diabetes) after 4 weeks of a megadose of Vitamin D. This will also help to calculate sample size for and choose an appropriate index for a larger randomized control trial which may be required subsequently.

The investigators wish to determine whether a short period of exercise training (5-10 days) improves the metabolic and cardiovascular response of people with or at risk of developing type 2 diabetes to eating a meal. In healthy people, blood flow to skeletal muscles increases after eating a meal, and this helps to regulate blood sugar levels by delivering blood sugar to muscles where it can be stored or metabolized. In people with or at risk of type 2 diabetes, blood flow does not increase as much after eating a meal, and this may contribute to elevated blood sugar concentrations observed in these individuals. The investigators wish to determine whether exercise can improve this response.

Background: Type 2 diabetes is a chronic disease that puts individuals at risk for serious health problems like heart disease, kidney failure, vision problems, and stroke. A major way that type 2 diabetes occurs is through insulin resistance. Insulin resistance means that insulin (an important hormone in the body to keep blood sugar normal) isn t working as well as it should, which can lead to problems with high blood sugar. Insulin resistance has been linked to mood problems, stress, and depression, especially in women. To determine if group programs can help reduce the risk for type 2 diabetes, researchers want to look at teenage girls who are at risk for developing the disease. Objectives: To test whether a group program designed to improve mood also can help improve insulin resistance in teenage girls who are at risk for developing type 2 diabetes, or whether a group program that teaches healthy living skills is just as helpful. Eligibility: Teenage girls between 12 and 17 years of age who are at risk for developing type 2 diabetes. Design: Participants will have two screening visits to find out if they are eligible to take part in the study. The first visit takes about 3 hours and will involve a physical exam, medical history, questionnaires and an interview about mood problems and possible depression. The second visit takes about 6 hours and will involve a full body scan to measure muscle and fat, blood draws and a glucose test to determine insulin resistance, questionnaires about general well-being and eating habits, eating meals and snacks, and an exercise test. Participants will join one of two group programs at the National Institutes of Health. One group focuses on learning skills to help with bad moods and stress. The other group covers topics that are important for teens to lead a healthy life. The groups will meet for 1 hour once a week for 6 weeks during after-school hours. At the end of the groups, participants will have three follow-up visits. The first visit will be 6 weeks later, the second will be 6 months after the start of the group program, and the third will be 1 year after the start of the group program. Each visit will take about 6 hours. These visits are similar to the second screening visit before the groups. Some participants will have extra tests to study stress at the second screening visit and the 6-week, 6-month, and 12-month follow-up visits. Participants will give samples of DNA, saliva to measure stress hormones, and they will take part in a brief stress test. For more information, visit the study website at: http://mir.nichd.nih.gov or contact the research coordinators for the study at 301-594-3198.

Studies of the human gut microbiome have suggested that treatment or prevention aimed at the obese microbiome could influence the development of obesity-associated metabolic disturbances. The objective of this project is to explore if a dietary intervention in 60 obese women with the probiotic Lactobacillus paracasei ssp paracasei F19 or flax seed fibres targeting the gut microbiome, can reduce insulin resistance, low-grade inflammation or dyslipidaemia, and to explore the interaction between the human genome and the gut microbiome. The study is based on the following hypotheses: Treatment with the probiotic Lactobacillus paracasei ssp paracasei F19 and flax seed fibres will lower the metabolic risk profile in the intervention groups compared with placebo. The effect on the metabolic risk markers can be correlated with changes in the gut microbiota (measured in faeces). After completion of the dietary intervention, the participants are offered a 10-week weight reduction program. Those who participate in the weight-loss program are invited to an optional follow-up visit in connection with the last visit at the clinical dietician, for the purpose of exploring the effect of weight loss on the gut microbiota and obesity-associated metabolic disturbances.

Oral contraceptives (OCs) are the most widely used method of reversible birth control. However, the long-term cardiovascular safety of the widely used low-dose OCs (ethinyl-estradiol < 50 mcg) is still debated. Although cardiovascular events are rare in young women whether they use OCs or not, the risks of myocardial infarction and ischemic stroke are increased among users of OCs who have conventional cardiovascular risk factors such as use of tobacco, diabetes or hypercholesterolemia. However, the risk of cardiovascular events in OC users with emerging cardiovascular risk factors (such as obesity and the metabolic syndrome) have not been investigated. Recently, the metabolic syndrome has been linked with the risk of cardiovascular disease. The syndrome is a clustering of risk factors in a single individual, and its underlying cause may be insulin resistance. Whether the metabolic syndrome predicts a higher cardiovascular risk in OC users has not been studied. This is a critical problem because the metabolic syndrome is prevalent in 24% of adults. Until the cardiovascular risks in users of OC are clearly defined, the appropriate use of OC with the least harm would not be possible. The investigator's long-term goal is to understand the best way to prevent and treat cardiovascular disease in women. The objective of this particular project is to obtain pilot data on the extent to which the metabolic syndrome and obesity affects glucose metabolism and cardiovascular risks in women taking OCs. The researchers hypothesize that women with metabolic syndrome and obese women will have worsened glucose metabolism and elevated cardiovascular risks associated with OC use, when compared to normal weight women without the metabolic syndrome. Results of this study will clarify the risk factors for cardiovascular events in women taking OCs, and will serve as pilot data for a National Institutes of Health (NIH) proposal. Once the cardiovascular risk factors of OC users are understood, clinicians can make better informed decisions about contraceptive choices for their patients.

The study is a behavioral clinical trial of aerobic exercise to determine dose-response effects on risk for type 2 diabetes, fatness, fitness, blood cholesterol levels, and other cardiovascular risk factors in overweight elementary schoolchildren. The hypothesis is that the more exercise a child does, the more benefit he or she will gain in reducing the risk of diabetes and other cardiovascular diseases. An ancillary study examined effects on cognition and achievement.

Polycystic ovary syndrome (PCOS) is a common endocrine disorder in reproductive age women, which causes disordered follicle growth and ovulation resulting in infertility. In addition women with PCOS have hyperandrogenemia and a dysregulated hormonal profile, resulting in altered feedback on the hypothalamic-pituitary-gonadal (HPG) axis. Obesity, insulin resistance, vitamin D (VD) deficiency and ageing worsen the symptoms. The gonadotrophins - follicle stimulating hormone (FSH) & luteinising hormone (LH), along with the pregnancy hormone human chorionic gonadotrophin (hCG) have structural similarities. The altered levels of FSH and LH in women with PCOS cause production of hCG from the brain leading to false positive pregnancy tests. Part one of this project will involve the investigation of this over-production of hCG in urine and serum of women with PCOS to develop suitable ovulation and pregnancy test kits, in collaboration with Swiss Precision Diagnostics (SPD). In Part two of the project, we would like to see if intervention with VD supplementation and/or using myo-inositol supplement compared with metformin (insulin sensitiser), improves prediabetes, distribution of fat/water content, weight loss and menstrual cyclicity in women with PCOS. We aim to correlate these interventions with particular serum & urine markers to develop better diagnostic tools.

The objective of this study was to determine how metabolic and inflammatory effects of physical exercise in overweight individuals are altered when sugar-sweetened beverages (SSB) are consumed after physical exercise. A randomized, controlled crossover trial was performed in which participants performed exercise with and without the ingestions of SSB during exercise or a non-exercise control condition to evaluate metabolic and inflammatory responses one day after the exercise and or SSB treatment.

The investigators examined the effect of vitamin D supplementation on glucose homeostasis and metabolic markers in healthy normal weight and overweight young subjects and healthy normal-weight and overweight elderly subjects living in Beirut, Lebanon.