Rediscovering Hydroxychloroquine as a Novel Insulin Sensitizer
Insulin ResistanceCurrent options to treat insulin resistance in diabetes are fairly limited. For this reason, novel treatments would represent a major progress. The generic drug hydroxychloroquine (HCQ) has poorly understood effects on blood sugar metabolism. In this study, the investigators will examine the mechanisms by which this drug affects glucose metabolism and which cells are affected. Findings emanating from this project will help establish whether HCQ may be a viable treatment for disorders of glucose metabolism.
Effects of Liraglutide on Hippocampal Structure and Function in Aging Adults With Prediabetes
Insulin ResistanceDementiaThe 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.
Effect of High-intensity Low-volume Training on Insulin Sensitivity in Type 2 Diabetes
Type 2 DiabetesHigh intensity interval training is applied for several diseases. Hypothesis: High intensity interval training improves insulin sensitivity in patients with type 2 diabetes.
The Health Effects of Blueberry Anthocyanins in Metabolic Syndrome (the CIRCLES-study)
Insulin ResistanceMetabolic Syndrome XThe purpose of this study is to determine the dose-dependent impact of 6 month freeze-dried blueberry powder intake on insulin sensitivity and resistance, cardiovascular disease risk factors, and lung and cognitive function in overweight and obese participants with metabolic syndrome. We will also examine acute post-prandial effects of blueberry intake (at baseline and at 6-months).
The Effects of Altering Physical Activity on Cardiometabolic Health
Insulin ResistanceThe effects of physical inactivity on variations in blood glucose and vascular health are not fully understood. The purpose of this study is to determine if an acute transition from physical activity to inactivity alters vascular health. Specifically, the investigators wish to examine in healthy, lean physically active individuals (obtaining greater than 10,000 steps/day) if decreasing physical activity (obtaining less than 5,000 steps/day) will alter blood flow following a meal a marker of vascular health. Furthermore, the investigators wish to examine if a one day return to physical activity (obtaining >10,000 steps/day) can restore the detrimental effects on blood flow following a meal.
The Effect of Gemcabene on Insulin Sensitivity in Nondiabetic Subjects
Insulin SensitivityThe purpose of this study is to determine the effect of gemcabene on insulin sensitivity as defined by average glucose disposal rate.
Detection of Salivary Insulin Following Meals
Insulin ResistanceIn addition to its role as the major regulator of glucose uptake into peripheral tissues, the hormone insulin is also a primary regulator of fat storage and fat burning of the body. Mechanistic animal studies have shown that high insulin may be the initial trigger for weight gain and be the proximal cause of obesity. There is currently no quick or non-invasive way of measuring insulin as research and clinical techniques require collection of a blood sample followed by a complicated and costly biochemical assay. The investigators will test the hypothesis that insulin levels can be accurately measured in saliva in humans following meals that elicit high and low blood insulin responses. Findings will help determine if insulin can be use as a valid fluid to track insulin changes in humans.
Microvascular Dysfunction and the Development of Whole-body Insulin Resistance
Insulin ResistanceType 2 Diabetes1 moreThis study aims to elucidate the role of the microcirculation in the development of whole body insulin resistance. The investigators hypothesize that impaired insulin signaling in the vasculature is an early phenomenon in the development of whole body insulin resistance. Furthermore, the investigators aim to identify improvement of microvascular function as a potential target in diabetes prevention and treatment.
Myo-inositol Versus D-chiro-inositol in the Treatment of Polycystic Ovary Syndrome and Insulin Resistance:...
PCOSInsulin resistance has important implications in the pathogenesis of the polycystic ovary syndrome (PCOS) and insulin-sensitizing drugs are considered a useful therapeutic approach. Reduction of insulin levels with administration of insulin sensitizing agents has been found to be beneficial in lowering both hyperinsulinemia, hyperandrogenemia, and restoring ovulation. Metformin alone or in combination with oral contraceptives (OCs) has been widely used in the long term treatment of women with PCOS in whom it modifies the ovarian morphology, improves intraovarian androgen levels, and enhances systemic and local insulin resistance. Despite to these beneficial effects, several side effects have been reported due to the long term administration of this drug. In the recent years, inositol has found more and more space in the reproductive clinical practice. Indeed, inositol have been classified as "insulin sensitizing agent" and it is mainly used as a chronic treatment for PCOS. Inositol exists in 9 different isomers and in particular several studies on Myo-inositol and D-chiro-inositol were reported. In this study myo-inositol versus D-chiro-inositol treatments were compared to placebo in women with PCOS and with or without insulin resistance.
Effect of Vagus Stimulation on Peripheral Glucose Metabolism
Insulin ResistanceGlucose IntoleranceTwo important mechanisms play a major role in the pathogenesis of type 2 diabetes: insulin resistance of the target tissues and the impaired insulin secretion from pancreatic β-cells. Postprandial factors (such as insulin) are perceived by the human brain and induce signals that regulate glucose metabolism via the parasympathetic nervous system. Transcutaneous auricular vagus nerve stimulation (tVNS) can be used on the outer ear to stimulate the auricular branch of the vagus nerve in humans. Heart rate variability (HRV) in healthy people can be significantly increased via tVNS, indicating a shift from sympathetic activity to parasympathetic activity. The hypothesis is that this postprandial shift results in a change in peripheral glucose metabolism. In turn, the increased parasympathetic activity could potentially result in a change in postprandial insulin sensitivity or secretion. To test this hypothesis, this study investigates the effect of vagal stimulation versus sham stimulation on insulin sensitivity, on insulin secretion, glucose tolerance, resting energy expenditure, and on parasympathetic tone (analysis of heart rate variability).