View clinical trials related to Insulin Resistance.
Filter by:Obesity is associated with low-grade inflammation, insulin resistance and low vitamin D status. Vitamin D has traditionally been known to involve in calcium homeostasis and prevent rickets; however, recently it has been recognized to inversely associate with many non-skeletal diseases and conditions including obesity and type 2 diabetes (T2DM). In vitro studies have demonstrated that vitamin D possesses anti-inflammatory properties. It remains unknown if the effect of vitamin D on insulin sensitivity is mediated by suppressing inflammation in human adipose tissues. The main objective of this study was to assess the association between vitamin D and insulin sensitivity and inflammation in morbidly obese pre-menopausal women. Obese women (n=76) were recruited from the University of Illinois at Chicago (UIC) Nutrition and Wellness Center and the UIC medical center bariatric surgery clinics. Insulin sensitivity/resistance was assessed by (1) Oral glucose insulin sensitivity (OGIS) index, derived from dynamic oral glucose tolerance test (OGTT), and (2) Homeostasis model of insulin resistance (HOMA-IR), calculated from fasting steady-state glucose and insulin. Also, to better understand the potential mechanism and the role circulating vitamin D (25OHD) plays in adipose tissue inflammation, we assessed messenger ribonucleic acid (mRNA) expression of vitamin D receptor (VDR) and various inflammatory genes in visceral (VAT) and subcutaneous adipose tissues (SAT) of obese women that underwent a restrictive bariatric procedure. We hypothesized that subjects with higher serum vitamin D levels would be less inflamed and more insulin sensitive and have increased expression of VDR and pro-inflammatory markers compared to those with lower serum vitamin D levels.
Vitamin D deficiency is extremely common in obese youth. In our obese population followed in the Endocrinology clinic at Children's Medical Center Dallas, vitamin D levels were inversely correlated with a measure of insulin resistance. We propose to show that correction of vitamin D levels in obese children and adolescents improves their insulin sensitivity. Obese youth presenting to the Center for Obesity and its Consequences on Health (COACH) clinic will be randomized to receive either the most recent Institute of Medicine (IOM) recommendations of minimum D3 dose of 600 IU/day (1), or receive higher doses of D3 such that the blood levels of vitamin D will be brought to a target level in either the low part or high part of the normal range. The goal is to determine if correction of vitamin D deficiency will improve insulin sensitivity in this group. Secondary goals include determining whether correction of vitamin D deficiency in obese adolescents and children results in less weight gain, and determining the amount of D3 required to correct vitamin D levels in this population. Our specific hypotheses are as follows: Hypothesis #1 Obese youth treated with Vitamin D3 who achieve low-normal 25-hydroxyvitamin D3 (OHD) levels (30-50 ng/mL) or high-normal 25-OHD levels (60-80 ng/mL) will have improved insulin resistance, as measured by Homeostatic Model Assessment of Insulin Resistance (HOMA-IR), compared to those individuals with deficient 25-OHD levels (< 30 ng/mL). Hypothesis #2 Subjects with a higher BMI will have higher Vitamin D dose requirements than current IOM recommendations of 600 IU/day and will take a longer period of time to reach target 25-OHD levels. Hypothesis #3 Subjects with normal 25-OHD levels will demonstrate less weight gain compared to subjects on the control arm.
The purpose of this study is to help scientist better understand the effect of a 12-week single daily evening dose of ramelteon (Rozerem ©), a drug that has been approved by the U. S. Food and Drug Administration (FDA) for the treatment of insomnia (trouble falling asleep or staying asleep). The study will measure levels of inflammation, fasting insulin and fasting glucose (sugar) in subjects who are taking either ramelteon (8 mg) or placebo.
Magnesium is an essential mineral found in many foods; rich sources include whole grains, green leafy vegetables, coffee, and legumes. Magnesium is a critical cofactor in >300 enzymatic reactions, including those related to energy metabolism. Reduced magnesium intake and serum concentrations have been detected, both cross-sectionally and prospectively,in type 2 diabetes and insulin resistance, hypertension, dyslipidemia, and cardiovascular diseases. Different studies have reported inadequate magnesium intake and low serum magnesium concentrations may correlated also with metabolic syndrome, defined as a cluster of metabolic disorders including obesity, hypertension, dyslipidemia and impaired glucose tolerance or diabetes mellitus. Previous studies on this subject, however, reported contradicting results. Some investigations reported inadequate magnesium intake and low serum magnesium concentrations while others did not. To our knowledge, the epidemiological evidence on the relation between dietary magnesium intake and risk of metabolic syndrome has not yet been summarized.Therefore, the investigators will perform a systematic review and dose-response meta-analysis to assess the association between dietary and circulating magnesium level and risk of metabolic syndrome.
Main scientific question: A previous intervention with an anti-inflammatory multifunctional dietary portfolio (MFD) showed remarkable reductions in cardiometabolic (CM) risk markers compared with a well-designed control diet. The study was performed under weight maintenance conditions in healthy subjects in a 4w crossover design (Tovar et al., 2012). MFD consumption also resulted in improved cognitive performance after 4 weeks (Nilsson et al., 2013). The present project will further study the preventive potential of MFD, using its unique properties for identification of new biomarkers and to evaluate the potential role of alterations in the gut microbiota. MFD will be tested in healthy at risk subjects in a randomized parallel design in an eight-week intervention with the test or control diet, respectively, allowing for weight loss. Assessment of standard anthropometric/biochemical markers of CM risk, metabolomics analysis and appetite regulating hormone evaluation are also planned. Associations between the gut microbiota composition and measures of CM risk are also included. The project provides unique opportunities to identify mechanisms for the metabolic impact of MFD, for further exploitation in innovative food and/or dietary concepts. Central hypothesis: The CM-preventive potential of MFD may be boosted in a medium-term trial under conditions allowing for body weight reduction. Expected additional benefits may be recorded as reduced values for conventional CM-related parameters, markers of modified gut microbiota composition and specific changes in blood metabolite profiles. Objectives: - To further improve the effect of MFD on biochemical/anthropometric CM risk markers in healthy subjects by administering the diet under conditions allowing for weight reduction. - To identify MFD-related changes in the gut microbiota associated with improved CM risk markers. - To assess MFD-related modification in metabolic pathways, studied with a metabolomics approach, and to correlate them with conventional clinical outcomes, aiming to identify new markers of altered metabolic risk.
The purpose of this study is to learn more about how U500 regular insulin can be effectively be used to treat type 2 diabetes. Most insulin treated patients with type 2 diabetes take U100 insulin, but if they require large doses (such as >150 units a day) they may experience pain at this site of injection and the absorption of the insulin is unpredictable, thereby leading to poor glucose control. To overcome these problems, doctors sometimes switch to a more concentrated form of insulin called U500 insulin. U500 is five times as concentrated as U100 insulin and therefore delivers an equivalent dose of insulin in much lesser volume. However, how to best use U-500 insulin is not certain. The investigators are not really sure how long a given dose is effective in patients who require large doses (>150 units of U100 insulin), so are not sure of how often the drug should be administered. In this study, the investigators will determine how effective two different doses of U-500 regular insulin (100 U and 200 U) are in lowering blood sugar and how long these two doses last. This information will help doctors develop better treatment plans for patients with type 2 diabetes.
Obesity is a complex and multifactorial disease representing a major public health challenge. Indeed, overweight and obese people carry a major risk of developing insulin resistance and type 2 diabetes mellitus. It has been demonstrated that polyphenols could be used to counteract some of the mechanisms involved in the generation of insulin resistance. The model of overfeeding represents a very good study model of the metabolic complications of obesity, since it has been shown to induce a transient state of insulin resistance in the human. The purpose of this research is to study the effects of a overfeeding (+50% of daily caloric needs over 31 days) with or without polyphenols supplementation (2g/days over 31 days) on insulin sensitivity measured in the setting of a hyperinsulinemic euglycemic clamp and on post prandial partitioning of exogenous lipids after a test meal. During 31 days, the volunteers will consume chocolate bars, chips, chocolate breads and cola in addition to their usual diet and will be supplemented with 2g of grape polyphenols extract or with placebo.
The main objectives of this study are to test the hypotheses that: 1) consumption of beverages sweetened with sucrose will increase risk factors for cardiovascular disease to a greater extent than a naturally-sweetened fruit juice such as orange juice, and 2) chronic psychological stress may augment the adverse metabolic effects of sugar intake. The study intervention consists of 2-week's consumption of 25% of energy as sugar provided either as a sucrose-sweetened beverage or naturally-sweetened orange juice.
The purpose of this study is to evaluate the effects of liraglutide on the memory and attention of people with insulin resistance. Liraglutide is a medication that makes the body more sensitive to insulin, and therefore may allow it to manage sugar more effectively. The investigators are looking specifically at a region of the brain that is associated with memory and attention, called the hippocampus, in order to see whether treatment this treatment will change performance on memory and attention tasks. The investigators are also taking an MRI of the brain to see whether there are changes to the size and shape of the hippocampus after treatment. All subjects in this study will be 50-70 years old and have pre- diabetes. Half of all subjects will have a family history of dementia, while the other half will not.
In a recent series of studies performed by our group, we have shown that exposure to hyperbaric oxygen (HBOT) leads to an increase in insulin sensitivity in male subjects and that this improvement can be measured in all men, not just those with diabetes. The aim of this study is to investigate the time course of this effect and explore the mechanisms involved when exposure to HBOT induces an increase in peripheral insulin sensitivity. Aims: 1. To determine whether the insulin sensitising effect of HBOT is apparent 24-hours after an HBO session. 2. To examine mechanisms underpinning the increase in insulin sensitivity following HBOT.