Active clinical trials for "Insulin Resistance"

Impaired brain vascular function precedes the development of reduced cognitive performance, while brain insulin-resistance is also associated with cognitive decline. Peanut consumption has already been shown to beneficially affect cognitive performance. However, underlying mechanisms have not yet been established, while well-controlled trials on longer-term effects of peanuts on cognitive performance are highly needed. The hypothesis is that longer-term peanut consumption has beneficial effects on (regional) cerebral blood flow responses (primary outcome), which may relate to an improved cognitive performance (secondary outcome) in older men and women. Important objectives are to investigate in older adults the effect of 16-week peanut consumption on (i) brain vascular function in cognitive-control brain areas, and (ii) brain insulin-sensitivity. We will also focus on changes in cognitive performance as assessed with a neuropsychological test battery (secondary objective). Cerebral blood flow responses before (brain vascular function) and after the administration of intranasal insulin (brain insulin sensitivity) will be non-invasively quantified by the non-invasive gold standard magnetic resonance imaging (MRI)-perfusion method Arterial Spin Labeling (ASL).

Animal and observational research in humans suggest that specific types of non-nutritive sweeteners (NNS) may impair glycemic control. However, whether NNS consumption impacts glucose homeostasis in middle-aged/older adults with prediabetes is unknown, and potential mechanisms by which this could occur have yet to be identified. The overall objective of this R21 proposal is to establish proof-of-concept for alterations in glucose homeostasis following intake of saccharin, but not acesulfame potassium, in middle-aged/older adults with prediabetes compared to a eucaloric diet with no NNS.

This is an 8 to14-week three-arm randomized controlled in children 8 to 12 years old. The main purpose of the study is to evaluate if stevia (as with other sweeteners and consistent with prior research in children and adults) has benefits for weight control and metabolic function relative to caloric sweeteners, and whether it provides benefits in this regard similar to water.

n a retrospective analysis of an exercise training program performed either in the morning or afternoon, we found that the afternoon training group improved their peripheral insulin sensitivity and fasting plasma glucose levels to a greater extent than the morning group. However, underlying mechanisms are unclear. The main objective of this study is to determine whether prolonged exercise training in the afternoon (15:00-17:00 PM) differs from exercise training in the morning (07:00-09:00 AM) in improving insulin sensitivity in individuals with pre-diabetes, and to investigate its underlying mechanisms.

The objective of the study is to quantify the relationship between physical activity, metabolic function, and appetite in adolescents. To do this we will test our working hypothesis that high levels of regular moderate-to-vigorous physical activity (MVPA), as opposed to body weight status, results in a metabolic phenotype consisting of enhanced metabolic function and proper regulation of appetite. We will randomly assigning sedentary overweight/obese adolescents (N=44) to either a control or structured-exercise group for three months.

With this study the investigators want to understand the physiological differences for people developing pre-diabetes and diabetes. The investigators hypothesize that different individuals go through different paths in the development of the disease. By understanding the personal mechanism for developing disease, the investigators will find a personalized approach to prevent that development. The investigators are also hoping to be able to find a biomarker that will pinpoint to the particular defect and thus, diagnose the problem at an earlier stage and have the information to give personalized diet recommendations to prevent the development of diabetes more effectively.

Aging is the number one risk factor for the majority of chronic diseases. There are no pharmaceutical treatments to slow aging and prolong healthspan. The anti-diabetic drug metformin is considered a likely pharmaceutical candidate to slow aging. In this study, the investigators hypothesize that metformin treatment in subjects free of type 2 diabetes will improve insulin sensitivity and glucoregulation in insulin resistant individuals, but will decrease insulin sensitivity and glucoregulation in insulin sensitive subjects. Further, the investigators hypothesize that long-term metformin treatment will remodel mitochondria in a way that decreases mitochondrial function in subjects that are insulin sensitive, but improves mitochondrial function in subjects that are insulin resistant. The investigators will use a dual-site, 12- week drug intervention trial performed in a double-blind, placebo-controlled manner on 148 subjects recruited from two separate sites (Oklahoma Medical Research Foundation (OMRF) and University of Wisconsin-Madison (UWM)). After consent and initial subject screening for chronic disease, subjects will be stratified to insulin sensitive (IS) or insulin resistant (IR) groups. Over a 12- week intervention, half of each group will take metformin and half will take a placebo. Pre- and post--intervention, subjects will complete a series of procedures to assess insulin sensitivity, glucose regulation, and biomarkers of aging. The same subjects will provide a skeletal muscle biopsy pre-- and post-intervention to assess the change in mitochondrial function and mitochondrial remodeling with and without metformin treatment. By completion of this project, the investigators expect to provide evidence that helps further delineate who may benefit from metformin treatment to slow aging.

Childhood and adolescence are crucial periods for prevention of obesity, as obese children are five times more likely to be obese at adulthood than lean children. To this purpose, sugar consumption should be reduced. The sugar alcohol erythritol is increasingly popular as sugar substitute in the food industry and is also recommended to diabetic patients. The substance is freely available. Recent acute studies show that erythritol has a positive influence on satiation and gastric emptying without affecting insulin and plasma glucose. In this trial, the investigators aim to assess the effect of a chronic intake of erythritol versus sucrose on insulin resistance in healthy adolescents. EryClot-Pilot: Erythritol is also produced by the human body and possibly elevated erythritol levels in the blood are an indication of an increased risk of cardiovascular disease, obesity or diabetes in the future. In a recently published study, a possible effect of erythritol on blood clotting function was described. In this in vitro experiment, increased blood clotting was observed when erythritol was added to clotting cells (platelets) in the test tube. Studies in humans on blood coagulation after administration of erythritol are missing so far. With a pilot study, the investigators study whether erythritol is detectable in the blood after administration of glucose and fructose. Furthermore, the erythritol level in the blood and a possible effect on the blood coagulation function after administration of erythritol will be investigated. These preliminary tests serve to clarify the data situation so that further studies can be based on them.

Animal and observational research in humans suggest that specific types of non-nutritive sweeteners (NNS) may impair glycemic control. However, whether NNS consumption impacts glucose homeostasis in middle-aged/older adults with prediabetes is unknown, and potential mechanisms by which this could occur have yet to be identified. The overall objective of this R21 proposal is to establish proof-of-concept for alterations in glucose homeostasis following intake of sucralose, but not aspartame, in middle-aged/older adults with prediabetes compared to a eucaloric diet with no NNS.

The purpose of this research study is to determine whether continuous glucose monitors (CGM) are a safe, effective, and acceptable way to evaluate type 2 diabetes risk in youth as compared to the standard 2-hour oral glucose tolerance test (OGTT). This study will involve wearing a CGM, wearing a physical activity tracker, responding to surveys, and completing at-home glucose and mixed food challenge while wearing the CGM. Subjects will also be asked to complete an interview by phone or videoconference after wearing the CGM.