Active clinical trials for "Insulin Resistance"

The purpose of this study is to test the effect of increasing the body pH acutely with an alkaline medication (sodium bicarbonate, NaHCO3, sodibic) on glucose metabolism post meal in non diabetic subjects with normal renal function. The investigators aim to determine whether there is an acute reduction in venous blood pH following a typical Western-style (high acid load) breakfast in healthy men and women, and whether this effect is attenuated by the concurrent administration of an alkaline medication. The effect on glucose metabolism, hunger/satiety and arterial stiffness post meal will be assessed.

Metformin is being compared to exercise and diet modifications. The researchers are interested in learning if the addition of metformin to lifestyle modifications is more helpful in treating the condition or disorder. Although metformin is FDA approved to treat type 2 diabetes, it is not FDA approved for the treatment of Non-alcoholic fatty liver (NAFLD) and is considered investigational for the purpose of this study.

There is growing epidemiological evidence that consumption of red meat is associated with greater incidence of Cardiovascular Disease (CVD) than either white meat or non-meat foods. Research from our group has shown that a high saturated fat (SF) diet with a moderate red meat content selectively increases intermediate density lipoproteins (IDL) and larger low density lipoproteins (LDLs), which are more weakly associated with CVD risk than smaller LDLs. In contrast, the investigators have found that with a similar intake of SF, high beef consumption results in a preferential increase in small and medium LDL particles that are strongly related to CVD. To date, no studies have directly compared the lipoprotein effects of red meat with that of other food sources of protein in the context of both high and low saturated fat intake. The overall objective of this project is to test the hypothesis that the effects of SF on lipoprotein markers of CVD risk are influenced by sources of dietary protein. The investigators hypothesize that adverse effects of SF on plasma levels of LDL-cholesterol (C), apolipoprotein B (apo B), and atherogenic LDL particles are greater in a diet with a high content of red meat than in diets in which the major proteins are from white meat (poultry) or non-meat sources. The investigators propose a clinical trial in which 180 healthy men and women will be randomized to high SF or low SF diet groups, and within each group, consume diets with equivalent amounts of protein from red meat, white meat, and non-meat sources for 4 wks each in random order. Specifically, the investigators will test whether: (1) With high SF, the red meat diet, compared to the other protein sources, will result in higher levels of LDL-C, apoB, small and medium LDL, and total/high density lipoprotein (HDL)C; (2) With low SF, dietary protein source will not be related to any of these measurements; (3) With both the white meat and non-meat protein diets, increased LDL-C with high vs. low SF will be due primarily to increases in large LDL, whereas with red meat the additional increase in small and medium LDL will result in greater increases in plasma apoB and total LDL particle number. Aim 4 will test hypotheses that increases in small and medium LDL with high SF plus red meat are related to increased activity of hepatic lipase, a key determinant of small LDL production, and that increases in large LDL induced by high SF are related to suppression of LDL receptors. The investigators will also assess the effects of protein source and saturated fat content on markers of insulin resistance, inflammation and endothelial function.

The rationale for the potential role of antioxidants in the prevention of cardiovascular diseases (CVD) remains strong despite the disappointing results of recent trials with a few select antioxidant vitamins. Glutathione (GSH) is one of the body's most powerful antioxidant agents but there is a surprising paucity of data on its use as an interventional therapy. Glutathione, when taken orally, is immediately broken down into its constituent amino acids, of which cysteine is the only one to be essential. Available cysteine is the critical determinant of intracellular GSH concentrations. N-acetyl cysteine (NAC) is an antioxidant supplement that has been used to provide a source of cysteine to replete GSH levels. By replenishing endogenous glutathione, it is possible that NAC would exert the same effect(s) as exogenous GSH. However, there is a new delivery system, liposomal GSH, which keeps glutathione intact. In this study, the investigators propose to match the cysteine content of NAC and GSH and compare the effects of these two supplements, at two different doses, on markers of inflammation and oxidative stress.

The study was designed to assess the effects of vitamin D supplementation during exercise training on body composition, muscle function, and glucose tolerance. The investigators hypothesis for these studies is that vitamin D supplementation enhances exercise-induced increases in strength and lean mass, potentially through enhancing insulin sensitivity and reducing inflammation.

North American blacks tend to have low blood levels of vitamin D because pigmentation blocks vitamin D production in the skin. They also have higher rates of developing type 2 diabetes and higher rates of complications from the disease compared with whites. Although there is compelling evidence that adequate vitamin D may reduce the risk for type 2 diabetes in whites, recent evidence from a national survey demonstrated an association of vitamin D with diabetes in whites but not in blacks. However, the central hypothesis of this study is that providing enough supplemental vitamin D to blacks (raising their blood levels higher than that of most participants in the survey) will improve blood measures related to diabetes risk. The proposed study is a 12-week randomized, double-blind, placebo-controlled experiment designed to examine the effect of vitamin D supplementation (100 μg/d ) on insulin secretion, insulin sensitivity and glucose control in pre-diabetic black men and women aged 40 and older.

The primary objective of this study is to examine the effects of four months of pioglitazone vs. metformin treatment on HDL cholesterol, triglycerides, blood pressure, insulin resistance, endothelial function, arterial stiffness, adipokines, oxidative stress, and blood biomarkers of endothelial activation in obese insulin resistant children. 30 obese children with elevated fasting insulin levels will be randomly assigned to pioglitazone or metformin for 16 weeks. Change in clinical variables over the 16-week study period will be compared between groups.

The current study is initiated in order to assess the impact of a PD solution containing L-carnitine on insulin sensitivity evaluated by measuring insulin requirement.

The major purpose of this study is to examine the effect of two sources of dietary omega-3 fatty acids, each given at two doses, on potential health benefits related to cardiovascular disease prevention. The two sources of dietary omega-3 fatty acids will be fish oil, and flaxseed oil.

SYSDIET (Systems biology in controlled dietary interventions and cohort studies) is one of the three centres in the NCoE Food, Nutrition and Health, 2007-2011. It consists of 12 partners from five Nordic countries working on multidisciplinary fields of science related to nutritional biology. The main objective of SYSDIET is to reveal mechanisms by which Nordic foods and diets could be modified to promote health and prevent insulin resistance, type 2 diabetes and cardiovascular diseases, all of which being connected to metabolic syndrome. Furthermore, the aim is to build up a Nordic platform for cohort studies and carefully conducted multi-centre dietary intervention studies, where novel nutritional systems biology tools can be applied besides human studies also in animal and cell culture studies. In order to achieve the main objective a Nordic multi-centre randomized controlled human intervention study is being conducted in 2009-2010 in 6-8 centres of SYSDIET consortium. Health of the Nordic populations has substantially improved during the last 30 years. This is due e.g. to marked decline in cardiovascular morbidity and mortality. However, during the last 10-20 years increasing obesity and sedentary lifestyle have resulted in an increase of metabolic syndrome and type 2 diabetes. Having this background, the aim of the SYSDIET consortium is to carry out a controlled, randomized dietary intervention study in persons with features of metabolic syndrome to find out the effects of a healthy Nordic food on major abnormalities in metabolic syndrome. Altogether 167 persons aged 30 to 65 years were recruited from 6-8 centers (40-60 subjects/center) of the SYSDIET cohort. The main inclusion criterion is BMI 27-38 kg/m2. The subjects should also have at least two other IDF criteria for metabolic syndrome. Recruited persons will start the study by following their conventional diet for one month as a run-in period. After that subjects will be randomly assigned into Experimental- or Control-diet-group for 6 months. Experimental diet is rich in whole grain products, berries, fruits, vegetables and fish, and its fat intake is modified according to current Nordic recommendations. Control diet is based on the current information of the mean dietary intake and food consumption. The diets will be realized according to eating habits in each Nordic country.