To assess the relationship between the fasting plasma glucose (FPG) concentration and insulin secretion in normal glucose tolerance (NGT) and impaired glucose tolerance (IGT) subjects, 531 nondiabetic subjects with NGT (n = 293) and IGT (n = 238; 310 Japanese and 232 Mexican Americans) received an oral glucose tolerance test (OGTT) with measurement of plasma glucose, insulin, and C-peptide ever...

Metabolic syndrome is a cluster of abnormalities that are often associated with prediabetes, a condition present prior to the onset of diabetes (1). The hallmark of both metabolic syndrome and prediabetes is insulin resistance, an impairment of insulin action within tissues at the level of the insulin receptor and subsequent cellular events. Insulin resistance resides mainly within muscle, live...

Somatostatin, the hypothalamic growth hormone release inhibitory factor (GHRIF), directly inhibits both the first and second phases of insulin secretion. The sensitivities of these two phases of insulin secretion to somatostatin differ remarkably. The first phase of secretion is approximately 25 to 50 times more sensitive to somatostatin inhibition than is the second phase. In addition, somatos...

AIMS/INTRODUCTION To assess the impact of smoking on impaired insulin secretion and insulin resistance in Japanese men. MATERIALS AND METHODS This study included 1,199 men aged 30-79 years without diabetes, impaired insulin secretion and insulin resistance at baseline who underwent a comprehensive medical check-up between April 2006 and March 2007 at Saku Central Hospital. Smoking status was ...

BACKGROUND: Many mechanistic steps underlying nutrient-stimulated insulin secretion (NSIS) are poorly understood. The influence of intracellular pH (pHi) on insulin secretion is widely documented, and can be used as an investigative tool. This study demonstrates previously unknown effects of pHi-alteration on insulin secretion in mouse islets, which may be utilized to correct defects in insulin...

beta cells sense glucose through its metabolism and the resulting increase in ATP, which subsequently stimulates insulin secretion. Uncoupling protein-2 (UCP2) mediates mitochondrial proton leak, decreasing ATP production. In the present study, we assessed UCP2's role in regulating insulin secretion. UCP2-deficient mice had higher islet ATP levels and increased glucose-stimulated insulin secret...

Abnormal insulin secretion results in impaired glucose tolerance and is one of the causal factors in the etiology of type 2 diabetes mellitus. Sidt2, a lysosomal integral membrane protein, plays a critical role in insulin secretion. Here, we further investigate its regulation in insulin secretion. We show that Sidt2(-/-) mice exhibit weight loss, decreased postnatal survival rate with aging, in...

To investigate the role of the autonomic nervous system in controlling insulin secretion 13 normal subjects and 5 patients with heart failure underwent insulin secretion tests. Alpha-adrenergic stimulation and beta-receptor blockade significantly depressed the secretion of insulin in response to intravenous tolbutamide in normal subjects, while both alpha-blockade and beta-stimulation significa...

The present studies were performed to elucidate the mechanisms responsible for the impairment of glucose-stimulated insulin secretion observed in fasting. Rats fasted for 48 hr displayed marked impairment in their insulin secretory response to both oral and intravenous glucose. Glucose-stimulated insulin secretion was restored within 24 hr by refeeding; actinomycin D given before refeeding bloc...

The dynamics of insulin secretion were characterized in response to a variety of physiological and pharmacological stimulators and other compounds in perifused pseudoislets generated from cells of the EndoC-βH1 β-cell line. Perifusion of EndoC-βH1 pseudoislets with the physiological stimulus glucose (16.7 mM) induced sustained insulin secretion, which was inhibited by mannoheptulose. The adenyl...