In health insulin is secreted in discrete insulin secretory bursts from pancreatic beta-cells, collectively referred to as beta-cell mass. We sought to establish the relationship between beta-cell mass, insulin secretory-burst mass, and hepatic insulin clearance over a range of age-related insulin sensitivity in adult rats. To address this, we used a novel rat model with chronically implanted p...

CONTEXT Methods to directly measure insulin resistance are invasive, complex, and costly. Surrogate indexes derived from the oral glucose tolerance test (OGTT) have been developed, but few studies have systematically analyzed these indexes. OBJECTIVE We examined the relation of surrogate and direct measures of insulin resistance to metabolic variables. DESIGN AND SETTING We conducted a cros...

OBJECTIVE To examine the effect of aging on insulin secretion (first- and second-phase insulin release) and insulin sensitivity in people with normal glucose tolerance (NGT) or impaired glucose tolerance (IGT). RESEARCH DESIGN AND METHODS First- and second-phase insulin secretion and insulin sensitivity were assessed in hyperglycemic clamp experiments in 266 individuals with NGT and 130 indiv...

Background. Insulin sensitivity and insulin secretion are traits that are both genetically and environmentally deter-

Both insulin resistance and insulin concentrations correlate with blood pressure in nondiabetic subjects, but there is no consensus on these relations in subjects with non-insulin-dependent diabetes, perhaps because of the use of nonspecific insulin assays and clinic blood pressure measurement. Therefore, we have investigated the relation between ambulatory blood pressure, insulin sensitivity (...

Insulin sensitivity and insulin secretion are reciprocally related such that insulin resistance is adapted by increased insulin secretion to maintain normal glucose and lipid homeostasis. The relation between insulin sensitivity and secretion is curvilinear and mathematically best described as a hyperbolic relation. Several potential mediators have been suggested to be signals for the beta cell...

Sclerostin, an inhibitor of bone formation, has emerged as a potential negative regulator glucose homeostasis. We aimed to investigate if serum sclerostin associates with insulin sensitivity, beta cell function, prediabetes or metabolic syndrome in healthy men. Serum was measured basal and insulin-stimulated samples from 526 men without diabetes the RISC cohort study. An OGTT performed at basel...

Muscle contractile activity is followed by an increase in the sensitivity of glucose transport to insulin. There is evidence suggesting that activation of p38 MAP kinase (p38) is involved in the stimulation of glucose transport by insulin and contractions. Exercise results in an increase in p38 phosphorylation that lasts for hours. In this context, we tested the hypothesis that activation of p3...

Background: Type 2 diabetes (T2D) is known as a common chronic metabolic disease worldwide. Coronary artery diseases are one of the hazardous disorders in diabetic patients. The current study aimed to investigate the relationship between dietary antioxidants intake with insulin resistance and insulin sensitivity among T2D without and with coronary stenosis (CS). Methods: This case-control study...

Hyperinsulinemia and insulin resistance have been linked to hypertension; however, the influence of sex on this relationship has not been well studied. The purpose of this experiment was to compare the effects of chronic insulin treatment on insulin sensitivity and blood pressure in male and female rats. Male and female Wistar rats were treated with insulin (2 U/day) via subcutaneous sustained ...