Active clinical trials for "Insulin Resistance"

In people with the metabolic syndrome, the investigators hypothesize that administration of a single 300 mg dose of a grape seed extract (GSE) will reduce insulin resistance (how well cells in the body can take up and use glucose), oxidative stress, and the amount of oxidized LDL in the blood during a 24 hour period. These measurements will be assessed at hourly intervals during the 24 hour study day protocol. Additionally, the investigators hypothesize that daily administration of 300 mg of GSE for 30 days will decrease baseline insulin resistance, oxidative stress, and the level of oxidized LDL in the blood.

The aim of the study is to evaluate the effect of hyperinsulinemia and postprandial changes in plasma glucose and lipids concentrations on the endothelial function together with other metabolic parameters in patients with type 2 diabetes (T2D) and in healthy subjects. Hypothesis: Different changes in endothelial function to acute in vivo induced hyperinsulinemia and after the meal test will be found in patients with T2D compared to healthy subjects. A significant relationships between insulin sensitivity, selected adipokines intramyocellular fat content, hepatic fat content and high energy phosphates in soleus muscle will be documented in both groups.

We examined the effects of short-term (2-wk) consumption of HF- and HG-sweetened beverages in adolescents (15-20 yr of age) on insulin sensitivity, insulin secretion, insulin clearance, triacylglycerol (TAG), and cholesterol concentrations.

This study will investigate the non-growth-hormone-dependent metabolic effects of the hormone Ghrelin in growth hormone deficient subjects by examining the insulin tolerance as well as signal proteins in fat and muscle biopsies.

The aim of this study is primarily to investigate the ability of antioxidants found in orange juice (OJ) to increase the body's sensitivity to the hormone insulin. Overweight or mildly obese women, who are otherwise healthy, will be recruited. The time commitment for subjects is ~14wks. Subjects will attend the laboratory on 5 occasions after fasting from midnight. The 1st is a medical screening. Laboratory visits 2 & 5 will take ~5hrs and will be separated by 3 months, during which time subjects will consume 250ml of an orange drink (either OJ or an orange flavoured control drink) once a day. During visits 2 & 5, subjects will have a scan to assess their %body fat using a low-dose x-ray machine, and have their insulin sensitivity measured using a technique called a 'Glucose Clamp'. During the 3hr glucose clamp, subjects receive an infusion of the hormone insulin and a glucose solution directly into their blood stream, with insulin sensitivity determined from the amount of glucose required to maintain blood glucose at normal levels. In addition, a small sample of fat tissue (about the size of a haricot bean) will be taken from underneath the skin of the belly. Subjects will record their food intake for 3-days in weeks 3, 7 and 11 of consuming the drink, and come to the lab for visits 3&4 during weeks 4&8. Laboratory visits 3&4 repeat measurements taken in the 1st (screening) visit.

Patients suffering from schizophrenia have a high risk to become obese and develop diabetes. Risk of obesity is particularly high with some newer schizophrenia drugs, such as clozapine or olanzapine. These drugs are called atypical drugs and exert their action in part by occupying receptors for serotonin, particularly the 5HT2A receptor subtype. This receptor may also interfere with glucose metabolism and insulin action. The purpose of this study is to compare an atypical antipsychotic drugs, olanzapine, which acts by occupying the 5HT2A receptor, to another antipsychotic drug, amisulpride, which mainly acts through the dopamine pathway. Healthy volunteers are recruited and asked to take a single dose of each drug and of placebo on separate days. Then, a combined glucose clamp study will be performed in order to test the effects of these drugs on insulin sensitivity and insulin secretion.

The study will assess the safety, tolerability, drug label and effect in subjects with and without insulin resistance.

Resveratrol, an ingredient of red wine and available in Canada in highly purified form as an over-the-counter health supplement, has been shown to have a number of health benefits. Data from in vitro and animal studies suggest that it has beneficial effects on insulin sensitivity and lipid lowering. The investigators are not aware, however, of any mechanistic studies that have examined the effect of highly purified resveratrol in vivo on lipoprotein metabolism in humans. Given the potential therapeutic benefit of resveratrol in correcting the metabolic abnormalities of insulin resistant individuals the investigators plan to examine the effects of resveratrol on intestinal and hepatic lipoprotein production in humans.

Antipsychotic medicines used to treat mental illnesses have been associated with effects on blood sugar control. Laboratory studies have shown that certain medications in particular may alter how insulin works. One purpose of this study is determine if antipsychotic medications have immediate effects on insulin action in individuals who do not have a mental disorder, but who have risk factors for diabetes. A second purpose is to demonstrate the feasibility of using volunteers without psychiatric disorders, and who do not take psychiatric medications, as a means for studying antipsychotic metabolic effects.

Recently EPO receptors have been found in human muscle tissue, but what is still not known is the physiological role of these receptors. In this study the researchers want to investigate if there is any effect of a acute administration of EPO on insulin resistance and/or substrate metabolism in muscle tissue.