Insulin sensitivity, reduced

Potenza MA, Marasciulo FL, Tarquinio M, Tiravanti E, Colantuono G, Federici A, Kim JA, Quon MJ and Montagnani M. 2007. EGCG, a green tea polyphenol, improves endothelial function and insulin sensitivity, reduces blood pressure, and protects against myocardial I/R injury in SHR. Am J Physiol Endocrinol Metab 292(5) E1378-E1387. 

Kemnitz, M. W., Elson, D. F., Roecker, E. B., Baum, S. T., Bergman, R. N., and Meglasson, M. D. (1994). Pioglitazone Increases Insulin Sensitivity, Reduces Blood Glucose, Insulin, and Lipid Levels, and Lowers Blood Pressure in Obese, Insulin-Resistant Rhesus Monkeys. Diabetes AS, 204-211. 

Brasnyo P, Molnar GA, Mohas M, Mark6 L, Laczy B, Cseh J, Mikolas E, Szijarto lA, Merei A, Halmai R et al (2011) Resveratrol improves insulin sensitivity, reduces oxidative stress and activates the Akt pathway in type 2 diabetic patients. Br J Nutr 106 383-389... 

The first hormonal signal found to comply with the characteristics of both a satiety and an adiposity signal was insulin [1]. Insulin levels reflect substrate (carbohydrate) intake and stores, as they rise with blood glucose levels and fall with starvation. In addition, they may reflect the size of adipose stores, because a fatter person secretes more insulin than a lean individual in response to a given increase of blood glucose. This increased insulin secretion in obesity can be explained by the reduced insulin sensitivity of liver, muscle, and adipose tissue. Insulin is known to enter the brain, and direct administration of insulin to the brain reduces food intake. The adipostatic role of insulin is supported by the observation that mutant mice lacking the neuronal insulin receptor (NDRKO mice) develop obesity. 

Thiazolidinediones (PPARy-agonists) Thiazolidine-diones ( pioglitazone, rosiglitazone) lower blood glucose levels in animal models of insulin resistance and also in insulin resistant patients. They are agonists of the peroxisome proliferator-activated receptor y (PPARy). Because they enhance the effect of insulin and reduce serum insulin levels in insulin resistant patients, thiazolidinediones are usually referred to as insulin sensitizers . 

Insulin sensitizer A substance that increases the action of insulin in peripheral tissues by reducing the effects of insulin resistance. 

Metformin is the only biguanide available in the United States. It enhances insulin sensitivity of both hepatic and peripheral (muscle) tissues. This allows for increased uptake of glucose into these insulin-sensitive tissues. Metformin consistently reduces A1C levels by 1.5% to 2%, FPG levels by 60 to 80 mg/dL, and retains the ability to reduce FPG levels when they are very high (>300 mg/dL). It reduces plasma triglycerides and low-density lipoprotein (LDL) cholesterol by 8% to 15% and modestly increases high-density lipoprotein (HDL) cholesterol (2%). It does not induce hypoglycemia when used alone. 

The prevalence of Type 2 Diabetes (T2D) is increasing world-wide and considered one of the main threats to human health in the 21st century. In 2010, 221 million patients are expected to be diabetic (compared to 151 million in the year 2000). The increase in diabetes prevalence is considered to be secondary to changes in human lifestyle accompanied by physical inactivity and unlimited food supply. Skeletal muscle insulin resistance, defined as the reduced response of skeletal muscle to a given dose of insulin, is a common finding in patients with type 2 diabetes mellitus and can be found before the onset and predict the development of the disease. Several factors determine skeletal muscle insulin sensitivity and among others alterations in fatty acid metabolism have been proposed. ... 

A conventional treatment algorithm involving clomiphene citrate (CC) followed by FSH induction of ovulation may result in a 71% cumulative single-ton live birth rate. In attempts to improve treatment outcome further and reduce complication rates, new compounds such as insulin-sensitizing agents or aro-matase inhibitors (Letrozole) are currently used increasingly. 

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