Insulin Resistance Clinical Trials

Muscle insulin resistance is a hallmark of upper body obesity (UBO) and Type 2 diabetes (T2DM). It is unknown whether muscle free fatty acid (FFA) availability or intramyocellular fatty acid trafficking is responsible for muscle insulin resistance, although it has been shown that raising FFA with Intralipid can cause muscle insulin resistance within 4 hours. The investigators do not understand to what extent the incorporation of FFA into ceramides or diacylglycerols (DG) affect insulin signaling and muscle glucose uptake. The investigators propose to alter the profile and concentrations of FFA of healthy, non-obese adults using an overnight, intra-duodenal palm oil infusion vs. an overnight intra-duodenal Intralipid infusion (both compared to saline control). The investigators will compare the muscle FFA storage into intramyocellular triglyceride, intramyocellular fatty acid trafficking, activation of the insulin signaling pathway and glucose disposal rates, providing the first measure of how different FFA profiles alter muscle FFA trafficking and insulin action at the whole body and cellular/molecular levels. By identifying which steps in the insulin signaling pathway are most affected, the investigators will determine the site-specific effect of ceramides and/or DG on different degrees of insulin resistance. Hypothesis 1: Palm oil infusion will result in abnormal FFA trafficking into intra-myocellular ceramides and abnormal insulin signaling. Hypothesis 2: Intralipid infusion will result in abnormal FFA trafficking into intra-myocellular saturated DG and abnormal insulin signaling. Read Less

This is a single-center, prospective, randomized, controlled (crossover) clinical study designed to investigate the specific dose-response impact of insulin infusion rate (IIR) on blood glucose levels during a pancreatic clamp study. The investigators will recruit participants with a history of overweight/obesity and evidence of insulin resistance (i.e., fasting hyperinsulinemia plus prediabetes and/or impaired fasting glucose and/or Homeostasis Model Assessment of Insulin Resistance [HOMA-IR] score >=2.73), and with evidence of, or clinically judged to be at high risk for, uncomplicated non-alcoholic fatty liver disease (NAFLD). Participants will undergo two pancreatic clamp procedures in which individualized basal IIR are identified, followed in one by maintenance of basal IIR (maintenance hyperinsulinemia, MH) and in the other by a stepped decline in IIR (reduction toward euinsulinemia, RE). In both clamps the investigators will closely monitor plasma glucose and various metabolic parameters. The primary outcome will be the absolute and relative changes in steady-state plasma glucose levels at each stepped decline in IIR. Read Less

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. Read Less

The purpose of this project is to examine the impact of increases in brain insulin on sympathetic nervous system activity, as well as peripheral and cerebral blood flow in humans. Read Less

This study is designed to determine the impact of extending sleep duration on glucose metabolism in people with obesity. Half of the participants will be instructed to increase their time-in-bed by one hour (sleep extension) while the other half will be be instructed to maintain their current sleep habits. Read Less

To determine if Inositol, a dietary supplement, will improve ovarian and adrenal androgen excess in women with Polycystic Ovarian Syndrome(PCOS). Read Less

The overall purpose of this study is to learn more about the metabolic effects of angiotensin-(1-7) in the insulin resistant state associated with obesity. Pharmacologic approaches to increase angiotensin-(1-7) levels or its actions are currently in development for treatment of metabolic-related diseases such as obesity and type II diabetes, based on findings from animal studies. It is unclear if this peptide contributes to the regulation of metabolism in humans. The investigators will test if angiotensin-(1-7) infusion can improve insulin sensitivity measured by hyperinsulinemic-euglycemic clamp methods in individuals with obesity and insulin resistance. The investigators will also examine for changes in blood pressure and related hemodynamic and hormonal changes following angiotensin-(1-7) infusion. Read Less

The primary goal of this study is to determine the dose of fatty acids that acutely induces mild insulin resistance in healthy volunteers. We hypothesize that a low-dose of fatty acid infusion (Intralipid/heparin) will cause a mild insulin resistance. The dose of fatty acid infusion that reliably causes mild insulin resistance will be selected for use in future studies. Read Less

The goal of this study is to collect more information from people with plaque psoriasis and to determine if insulin plays a role in the pathogenesis of psoriasis. The main question it aims to answer is if insulin action is preserved or even enhanced in psoriatic lesions despite insulin resistance elsewhere. Participants with plaque psoriasis will have punch biopsies taken of lesional and non-lesional skin after an overnight fast and then during an oral glucose tolerance test. Biopsy specimens will then be assessed for markers of insulin action. Read Less

The purpose of this study is to understand and determine whether Palmitoleic acid (POA), monounsaturated omega-7 fatty acid (exists in regular diet), improves insulin sensitivity and decreases liver fat accumulation in humans. Unlike others, the study will use POA as a dietary supplement, rather than complex oils, which contain a significant amount of saturated fat palmitic acid. Palmitic acid has known harmful effects on the body. Hence, eliminating palmitic acid from supplementation of POA might increase its benefits. This trial stems from the preclinical discoveries that POA acting as a fat hormone, has beneficial effects on the liver, muscle, vessels, and fat tissue. Supporting this, higher POA levels in humans have been shown to be correlated with a reduced risk of developing type-2 diabetes and cardiovascular diseases such as heart attacks. In animals, it has been observed that POA improves sugar metabolism in a number of mechanisms related to the liver and muscle. Based on these findings, the design of this study is a double-blind placebo-controlled trial that tests the effects of POA on insulin sensitivity of overweight and obese adult individuals with pre-diabetes. Read Less

The use of continuous glucose monitoring (CGM) in earlier data has inspired behavioral changes leading to improved adherence to an exercise plan in individuals and eating habits in people with diabetes. Mobile health (mHealth) platforms provide satisfactory, easy-to-use tools to help participants in the pursuit of weight change goals. We hypothesize that the use of CGM data and the Signos mHealth platform will assist with weight control in a population of people with type 2 diabetes mellitus who are not using insulin. Read Less

Obstructive sleep apnea (OSA) is a common condition associated with significant adverse health outcomes. Our overarching hypothesis is that patients with OSA and hypoxia (H-OSA) have greater degrees of insulin resistance in both liver and adipose tissue when compared to those without hypoxia (NH-OSA) thus leading to increased risk for the development of diabetes in the former group. Read Less