View clinical trials related to Insulin Sensitivity.
Filter by:The overall objectives of this study are to examine the relationships between circulating vitamin D, insulin sensitivity, and multiple indices of vascular function and to examine whether vitamin D deficiency in African Americans (AA) and White Hispanics (WH) is responsible for ethnic differences in insulin sensitivity and hypertension in AA, WH and European Americans (EA), as well as mechanisms underlying the association between insulin resistance and blood pressure. We hypothesize that 1) serum 25(OH)D is associated with insulin sensitivity and vascular functioning, independent of adiposity, 2) lower insulin sensitivity and vascular functioning in AA and WH relative to EA is due to lower circulating 25(OH)D in AA, and 3) the relationship between insulin resistance and vascular dysfunction is mediated by 25(OH)D. Acronyms: African American (AA), European American (EA), White Hispanics (WH), Serum 25-hydroxy vitamin D (25()H)D, Body mass index (BMI), Alabama (AL).
The overall objectives of this study are to examine the relationships between circulating vitamin D, insulin sensitivity, and multiple indices of vascular function and to examine whether vitamin D deficiency in AA is responsible for ethnic differences in insulin sensitivity and hypertension in AA and EA, as well as mechanisms underlying the association between insulin resistance and blood pressure. We hypothesize that 1) serum 25(OH)D is associated with insulin sensitivity and vascular functioning, independent of adiposity, 2) lower insulin sensitivity and vascular functioning in AA relative to EA is due to lower circulating 25(OH)D in AA, and 3) the relationship between insulin resistance and vascular dysfunction is mediated by 25(OH)D. Acronyms: African American (AA), European American (EA), Serum 25-hydroxy vitamin D (25()H)D, Body mass index (BMI), Alabama (AL).
In this study we hypothesize infusion of Angiotensin II improves the insulin-induced microvascular dilatation and therefore insulin-mediated glucose uptake. Objectives: Does infusion of Angiotensin II increase insulin-mediated glucose uptake via enhanced insulin-mediated microvascular function in healthy subjects?
The purpose of this study is to evaluate the effect of blueberry powder on insulin sensitivity in obese, non-diabetic, and insulin resistant subjects. The investigators hypothesized that supplementation with blueberry powder will result in an increase in insulin sensitivity in obese subjects with insulin resistance.
A 12 wk aerobic exercise program will reduce visceral, hepatic and intramyocellular fat accumulation and improve insulin sensitivity and glucose metabolism in obese sedentary Hispanic adolescents.
The study is designed to test the following primary hypothesis: - Aerobic exercise training will improve insulin sensitivity in insulin resistant subjects through changes in the major cellular signaling pathways and and/or their regulators. Accordingly, the proposed study is designed to accomplish the following specific aims: - Quantitate how exercise training improves insulin sensitivity and decreases cardiovascular risk factors in a general population of lean, nondiabetic, insulin resistant subjects. Effects on known cardiovascular risk factors including blood pressure and serum lipoproteins will be evaluated. Change in regional adiposity will also be measured - Determine the effects of a program of regular aerobic exercise on in the insulin receptor signaling pathway. Biopsies of vastus lateralis muscle from insulin resistant subjects will be obtained before and after a hyperinsulinemic glucose clamp. This procedure will take place in the untrained state and after exercise training. The investigators will measure changes in the insulin receptor and the activity of the major components of the intracellular insulin signaling pathway. The investigators will also look intracellular proteins that regulate this signaling pathway.
An increase of longevity and of the number of men and women older than 60 years old is observed in most industrialized countries. Aging is a complex, multifactorial and continuous process involving physical and biological modifications such as a notably decrease in glucose tolerance and type 2 diabetes risk. Insulin sensitivity follow-up during aging is difficult mainly because of many confounding factors (environment, lifestyle). In 2006, SUVIMAX 2 study began, based on the monitoring of volunteers who participated in former SUVIMAX study (1994-2003). This study was a randomised trial which was designed to study the link between a low antioxidant intake and risk of cancer or ischemic heart disease. The subjects recently had a health check-up including complete information about their diet, physical and neurosensory status. Based on these data, a score was established to classify subjects according to their quality of aging ("successful aging versus "problematic aging") These volunteers, who undertook a 13-year follow-up (dietary and medical status), constitute the reference population to determine the mechanisms involved in the insulin resistance development in aging. The purpose of our research work is to determine whether the quality of aging could influence insulin sensitivity, by studying metabolic profile and change in gene expression (genes involved in glucose metabolism and metabolic senescence in muscle tissue) during aging.
Insulin-resistance plays an important role in polycystic ovary syndrome (PCOS) physiopathology. The phosphoprotein enriched in the diabetes (PED/PEA-15), a 15 kDa protein related to insulin sensitivity, is over-expressed in type 2 diabetic patients and in PCOS women, independently of obesity. The effectiveness of oral contraceptives pills (OCP) or metformin (MET) in PCOS management is still uncertain. Aim of this pilot clinical study was to compare the effects of OCPs or MET on the expression of PED/PEA-15 in association with insulin sensitivity in obese PCOS women. Outcome measures: PED/PEA-15, BMI, plasma glucose and insulin, 1/HOMA-IR, homeostasis model assessment of insulin resistance; QUICKI, quantitative insulin sensitivity check index; ISI: whole-body insulin sensitivity index. Study design: twenty obese PCOS women (age: 24.7±18 yr; BMI: 30±2.4 kg/m2) were randomized according to insulin sensitivity to receive 30 µg ethinylestradiol plus 30 mg drospirenone 21 day/month or MET 1250 mg three times daily for 6 months. Results: At baseline, age and BMI were not different in the two groups; PED/PEA-15 protein expression was higher in MET than in OCP group (p=0.011), along with higher 1/HOMA-IR (p=0.004), and lower QUICKI and ISI (p=0.003 and p<0.001, respectively). After treatment, independently of body weight, only in MET group PED/PEA-15 decreased (p=0.004), along with insulin and 1/HOMA-IR (p<0.001), and QUICKI and ISI increased (p<0.001). Insulin sensitivity indexes improvement correlated significantly with PED/PEA-15 protein expression, but not with BMI. Conclusions: PED/PEA-15 protein over-expression in obese PCOS women with IR reduced after a six month treatment with MET, while remained unchanged in the OCP group. The reduction was independent of body weight, and correlated with insulin sensitivity indexes. This effect further supported MET as a more effective therapy than OCPs for obese PCOS women with IR, also when fertility is not required.
The purpose of the study is to determine the effect of three weight loss surgeries compared to a low calorie diet with regard to energy expenditure, body composition, insulin sensitivity, and the response of gastrointestinal peptides to a standard meal. Baseline assessments will be conducted in all four groups and changes will be compared six and fifty-two weeks post-operatively.
The purpose of the study is to assess the relationship between vitamin D status and insulin- glucose dynamics in obese Adolescents. The study is intended to assess the difference in the insulin sensitivity before and after correction of vitamin D deficiency.