Insulin Resistance : Heart Failure
Congestive Heart FailureHeart FailureWhether insulin resistance common among Chronic Heart Failure (CHF) patients in Tayside and identify factors associated with insulin resistance in CHF. We also want to identify mechanism for the impaired exercise capacity and reduced peak VO2 in CHF
Milk Fat Intake and Metabolic Health Markers
Insulin SensitivityType 2 DiabetesThis study investigates the effects of bioactive fatty acids in full fat dairy (whole yogurt), on insulin action, calorie needs, blood lipids, immune function, and body composition in normal and overweight male and female volunteers.
Surgical Stress After Laparoscopic Compared to Open Liver Resection
Insulin ResistanceThe purpose of this study is to determine whether the postoperative insulin resistance and cytokine release would be attenuated in laparoscopic compared with open liver resection.
Influence of Brain Insulin Sensitivity on Peripheral Insulin Sensitivity
Insulin SensitivityThe researchers will investigate if brain insulin action influences peripheral insulin sensitivity in healthy humans.
Adiponectin and Ethnic Differences in Insulin Resistance
Insulin ResistanceType 2 DiabetesThe purpose of this protocol is to measure and compare levels of the circulating protein adiponectin and adiponectin's association with insulin sensitivity in Mexican Americans and non-Latino white subjects. The investigators also aimed to examine associations between nutritional factors and adiponectin levels.
Gastric Emptying and Insulin Response to Test Drink
Insulin ResistanceSurgery is a stress on the body and recovering well after surgery is very important to patients and their doctors. It is therefore important to prepare patient's bodies for the stress of surgery, and one way to do this is to provide proper nutrition. In the past, patients were asked to prepare for surgery by fasting from midnight before surgery. Today, it is known that this practice is not beneficial to patient's recovery. In fact, it has been recognized that drinking a sugary beverage (e.g., juice) before surgery stimulates the production of insulin, which is a hormone that helps make the proteins needed for wound healing after surgery. This is currently practiced at the MUHC. It might also be beneficial, however, to drink a beverage that contains sugar and whey proteins (a protein isolated from milk) before surgery. In fact, whey proteins stimulate insulin and may also have the added benefit of improving muscular strength. In this study, investigators will measure the level of insulin produced after drinking a carbohydrate (i.e., sugar)-whey protein beverage to determine how it compares to the level of insulin produced after drinking the sugary beverage used at the MUHC.
Insulin Resistance in the Control of Intestinal Lipid Metabolism
Insulin ResistanceType 2 DiabetesAmerica's preferential consumption of high-fat/high-sugar foods is a driving force in the current epidemic of obesity and insulin resistance. Recent scientific observations suggest that the taste of food may play a role in how the body processes the food eaten in a meal. The intestine may play a central role in all aspects of dietary fat metabolism, from initial encounter with taste buds in the mouth to eventual triglyceride (TG) storage in the body. The investigators hypothesize that elevated blood fats in insulin resistance are a result of elevated intestinal-TG secretion and poor communication of this organ to the rest of the body after meals. In this study, meal feeding and sensory studies will be performed to determine whether the mechanism of taste-associated intestinal signaling leads to higher levels of blood fats after meals in 24 healthy, insulin resistant and type 2 diabetic subjects. Individuals will consume special meals the night before the tests and participate in sensory tests in the morning to analyze the effect of taste. The goal of this work is to understand how insulin resistance may cause impaired signaling between the taste buds and the intestine to result in an elevation in blood lipids, which increases the risk for other chronic diseases. This study will generate data for a future study to understand how diabetes treatment affects this process.
Influence of Central Nervous Insulin Action on Insulin Sensitivity of Peripheral Organs in Lean...
Insulin ResistanceResearch in animals and first experiments in humans indicate that insulin action in the brain regulates peripheral insulin sensitivity. One major organ might be the liver. Previous studies in humans showed that the human brain is an insulin sensitive organ in lean but not in overweight/obese persons. Therefore, this study will include lean versus overweight/obese persons. In this study, insulin action will be introduced by intranasal insulin administration in lean and overweight humans. As a control, placebo spray will be administered. To mimick the known spill over of small amounts of intranasal insulin into circulation, a small bolus of insulin will be administered over 15 minutes following placebo spray application. Peripheral insulin sensitivity will be assessed by hyperinsulinemic-euglycemic glucose clamp and glucose uptake and endogenous glucose production will be assessed by tracer dilution technique. Autonomous nervous system activity will be addressed by heart rate variability. Involved brain areas will be addressed by fMRI before and after nasal insulin application.
Study of the Effect of Testosterone Treatment on Metabolic Parameters and Urinary Symptoms in Bariatric...
ObesityHypogonadism2 moreThe primary purpose of the study is to evaluate, in obese and hypogonadal patients eligible for bariatric surgery, the effect of testosterone replacement therapy in improving lower urinary tract symptoms (LUTS) assessed using the IPSS (International Prostate Symptom Score) questionnaire, compared to hypogonadal untreated subjects and eugonadal subjects.
Insulin Sensitivity, Irisin and Adipokines as Outcome Parameters in Patients Undergoing Cardiac...
Insulin ResistanceDiabetes Mellitus Type 21 moreBACKGROUND: Surgical injury and inflammation provoke a stereotypical stress response. Insulin resistance plays an intriguing role in these metabolic alterations and depends on the intensity of injury. Metabolic derangements resulting from peripheral insulin resistance are unambiguously related to adverse outcomes and higher perioperative complication rates. Therefore, insulin resistance offers to act as a marker for stress and is potentially relevant in predicting clinical outcome. Plasma-glycosylated hemoglobin A (HbA1c) is an established indicator for blood glucose control and has a prognostic value regarding outcomes after major surgical interventions. Adipose tissue holds a key function in endocrine metabolism by releasing multiple substances, so-called adipose-derived secreted factors or adipokines. Recent studies have linked several adipokines to overall insulin sensitivity in metabolic syndrome-related conditions as well as in critical illness. Irisin, a recently identified myokine acts on white adipose tissue and plays a role in the prevention of insulin resistance. AIMS OF THE STUDY: The aim of this study is to assess the level and the effects of perioperative insulin resistance on clinical outcome in cardiac surgery patients. Based on previous studies suggesting glucose homeostasis and insulin resistance are associated with severity of illness and outcome in critically ill patients,it is proposed that patients with marked insulin resistance suffer from worse clinical outcome. This study protocol evaluates the ability of homeostasis model assessment (HOMA), quantitative insulin sensitivity check index (QUICKI), HbA1c, the adipokines Angiopoietin-like protein 2 (ANGPTL2), C-X-C motif chemokine 5 (CXCL5), and visfatin, and the myokine irisin to indicate perioperative insulin resistance and explores for correlation with adverse clinical outcomes after 30 days. MATERIAL & METHODS: 325 patients admitted to the surgical intensive care unit after elective on-pump cardiac surgery will be consecutively enrolled. Baseline characteristics and routine blood samples will be assessed the day before surgery. Study blood samples will be drawn preoperatively in the induction bay of anesthesia to measure the insulin resistance indices HOMA and QUICKI, HbA1c, ANGPTL2, CXCL5, visfatin, and irisin. Blood glucose, irisin, adipokines, and routine biochemical tests will be assessed upon admission to the intensive care unit and on postoperative days 1 and 3. Adverse outcomes will be assessed 30 days after surgery. Sample size is set to ensure at least 80% power at a significance level of 0.05.