Mechanisms of Cerebrovascular Control
Metabolic Syndrome XThe objective of this study is to identify insulin-specific cerebral blood flow (CBF) control mechanisms, and establish cerebrovascular responsive baseline in younger (18-45 yrs) metabolic syndrome adults (MetSyn) who are at substantial risk of stroke and other types of cardiovascular mortality even if they never develop diabetes. The central hypothesis is that vasodilator actions of insulin are impaired in MetSyn due to loss of dilator and gain of constrictor signals. This study will focus on 2 mechanisms that likely limit CBF in MetSyn: 1) Disruption of nitric oxide (NO) vasodilation, and 2) Exaggerated endothelin (ET-1) constriction. Three specific aims will be addressed: Aim 1: To test the hypothesis that physiologic surges of insulin acutely increase CBF in young adults, but adults with MetSyn exhibit paradoxical insulin-mediated vasoconstriction. Aim 2: To test the hypotheses that key mechanisms responsible for poor CBF in MetSyn are shifts in NO and ET-1 signaling. Specifically, in healthy controls, NO mediates robust dilation, with little to no ET-1 constriction. In contrast, adults with MetSyn exhibit uncoupled NO synthase (NOS) and exaggerated ET-1 constriction. Aim 3: To test the hypothesis that insulin regulation of CBF is regionally distinct (e.g. Middle Cerebral Artery (MCA) reactive than Anterior Cerebral Artery (ACA) or basilar), and the negative effects of insulin resistance (IR) are similarly regionally specific.
Dairy Macronutrient Effects on the Metabolic Syndrome
Metabolic SyndromeThe investigators examined the effects of 4-week dietary protein intake in mixed meals at two levels of protein amount on whole body glucose metabolisms in older adults with metabolic syndrome.
Probiotic Bacteria in Prevention of the Metabolic Syndrome
Metabolic Syndrome XThe metabolic syndrome is increasing worldwide, including developing countries. The metabolic syndrome is composed of clinical expressed symptoms as central obesity, high blood pressure, raised fasting plasma glucose or diagnosed diabetes, low HDL, and raised serum triglycerides. All those components together or independently contribute to the development of cardiovascular diseases, which are the leading cause of death in the modern world. The results from previous studies have shown that probiotic bacteria have an influence on health improvement, and can exert positive effects on diseases as diabetes, high blood pressure, dyslipidemia and low-grade inflammation, which are all components of the metabolic syndrome. The objectives of this study were to investigate which of probiotic strains Lactobacillus plantarum PCS 20, Lactobacillus plantarum PCS 26 in Lactobacillus rhamnosus GG exert positive effects in the cascade of molecular reactions at the level of small intestines, at remodeling of monocytes/macrophages and adipocytes in human cell model of non-cancerous origin, and to provide scientific explanation of mechanisms of possible multi-leveled activity of selected probiotic strains in patients with metabolic syndrome. For this purpose, the investigators divided this research into two parts. The first part consisted of pre-clinical in-vitro laboratory study. It examined the mechanisms of actions of probiotic cultures with the use of functional cell models of non-cancerous origin, more specifically, with the use of cell lines of human intestinal epithelium, human monocytes/macrophages and human visceral preadipocytes. In in-vitro laboratory study, the investigators demonstrated that probiotic strain Lactobacillus plantarum PCS 26 exerts positive effects, which could help to relieve the particular components of the syndrome in the host with metabolic syndrome. The second part of the research consisted of prospective, double-blind and placebo-controlled in-vivo pilot clinical study, which included 16 volunteers with the metabolic syndrome. Results have shown that probiotic strain Lactobacillus plantarum PCS 26 exerts positive effects on reduction of waist circumference, on lowering of serum cholesterol concentration, and on maintenance of serum adiponectin levels. Those effects together can contribute to the alleviation of the metabolic syndrome, especially in terms of clinical manifestation and risks in relation to cardiovascular diseases.
Mesoglycan, Vascular Reactivity and Metabolic Syndrome
Metabolic SyndromeThe purpose of the study was to characterize the action of mesoglycan on vascular endothelium through the non-invasive assessment of vascular reactivity humeral artery by comparing effects of mesoglycan on Flow Mediated Dilatation (FMD) of the humeral artery between a group of patients with metabolic syndrome assuming placebo and a group of patient with metabolic syndrome assuming mesoglycan; firstly after administration of the drug/placebo intramuscularly, and then, in a study of medium-term after oral intake of drug/placebo. The selection of patients with metabolic syndrome is related to the fact that this syndrome is associated with alterations in endothelial function and a high incidence of cardiovascular events. So it is a condition that offers the opportunity to explore the hypothesis that the mesoglycan may have a favorable effect on early vascular alterations that precede clinical events.
Exploring the Molecular Basis to Healthy Obesity: The Diabetes Risk Assessment Study
ObesityType-2 Diabetes2 moreThe purpose of this study is to better understand the genetic and metabolic differences in obese individuals with and without type 2 diabetes. It is expected that this research will help improve our understanding of the variability observed between obese and diabetic individuals.
Metabolic Phenotyping of Individuals Born Following Assisted Reproduction Techniques
Metabolic SyndromeDiabetesThis study is to compare the effects of high fat overfeeding on metabolic risk factors in children born though assisted reproduction technologies (ART) versus children conceived naturally (controls). The investigators will utilize state of the ART measures to characterize the physiological, endocrine and molecular responses to high fat overfeeding. The investigators hypothesize that children conceived following ART will have greater responses to high fat dietary challenge and that this will be associated with DNA hypermethylation of genes that are involved in lipid metabolism.
Salusin-alpha - a New Factor in the Pathogenesis of Lipid Abnormalities in Hemodialysis Patients...
Renal Failure Chronic Requiring HemodialysisMetabolic Syndrome2 moreHyperlipidemia and atherosclerosis lead to cardiovascular diseases and are an indirect cause of increased death rate in the general population. This association is still more evident in specific subpopulations, like patients with advanced chronic kidney disease (CKD), especially hemodialysis (HD) patients, due to a higher prevalence of lipid disturbances and atherosclerosis compared to the general population. Cardiovascular events in CKD patients are frequently associated with traditional risk factors, including diabetes, male sex, hypertension, dyslipidemia and advanced age. However, these factors failed to fully account for the increased risk of cardiovascular events in CKD. The efforts are made to identify new risk factors that contribute to the development of atherosclerosis and participate in causes of cardiovascular death. In 2003, there were identified peptides designated salusin-alpha and salusin-beta. Development of atherosclerosis may be suppressed by salusin-alpha. Salusin-alpha may have a lipid lowering effect, similar to that of statins. The purpose of this study is to investigate whether 1) salusin-alpha is associated with lipid metabolism of HD patients (without or with metabolic syndrome or type 2 diabetes mellitus), similarly or not like in healthy or obese subjects; 2) treatment with atorvastatin and its effects are associated with changes in plasma salusin-alpha concentration, if so - whether it is dependent on the direct influence of atorvastatin on salusin-alpha or associated with a decrease in serum lipid level; 3) salusin-alpha may predict mortality in HD patients.
The Metabolic Effects of Consuming Sugar-Sweetened Beverages for Two Weeks
Metabolic SyndromeInsulin Resistance1 moreThe purpose of this study is to examine the effects of consumption of sugar-sweetened beverages on blood triglycerides and cholesterol, cholesterol concentrations, and the body's sensitivity to insulin.
Effects of an Amino-acid Supplement on Hepatic Lipid Metabolism
Metabolic Syndrome10 healthy male volunteers will be studied after a 6 day weight maintenance, balanced diet a 6 days weight maintenance, balanced diet supplemented with 3 grams fructose/kg body weight/day a 6 days weight maintenance, balanced diet supplemented with 3 grams fructose/kg body weight/day and 20g amino-acids per day At the end of each 6 days period, the following measurements will be obtained intrahepatic lipids (1H-MRS) metabolic effects of fructose ingestion (measurement of substrate oxidation, gluconeogenesis from fructose, palmitate synthesis from fructose, plasma VLDL-kinetics) This is a randomized, double blinded study
The Impact of Free Fatty Acid Reduction on Vascular Function in the Metabolic Syndrome
Metabolic SyndromeThis study will test the hypothesis that reducing the release of free fatty acids (FFA) from fat cells will restore insulin-mediated, endothelium-dependent vasodilation in people with the metabolic syndrome.