Several growth hormone-independent 25-31,000 kD insulin-like growth factor binding proteins (IGF-BPs) have been identified in plasma, extravascular fluids, and various cell-conditioned media. Cultured human decidual cells release three IGF-BPs with 24,000, 30,000, and 34,000 Mr. Using ligand blot analysis and an RIA for the 30,000-Mr form (IGF-BP-1), we examined the effects of IGF-I (10-1,000 n...

Given its wide spectrum of biological activities such as growth hormone (GH) release, feeding stimulation, adiposity and cardiovascular actions, the discovery of ghrelin opened many new perspectives within neuroendocrine, metabolic and cardiovascular research, thus suggesting its possible clinical application. Circulating ghrelin is produced predominantly in the stomach, and its receptor GH sec...

The release of carboxypeptidase H activity from isolated rat islets was determined and compared to the secretion of immunoreactive insulin. Analysis of pancreatic islet cells sorted into beta and non-beta types indicated that approx. 80% of islet carboxypeptidase H activity is present in the beta cell. The release of both insulin and carboxypeptidase H was stimulated markedly by increasing the ...

Leucine and monomethyl succinate initiate insulin release, and glutamine potentiates leucine-induced insulin release. Alanine enhances and malate inhibits leucine plus glutamine-induced insulin release. The insulinotropic effect of leucine is at least in part secondary to its ability to activate glutamate oxidation by glutamate dehydrogenase (Sener, A., Malaisse-Lagae, F., and Malaisse, W. J. (...

Because glucokinase is a metabolic sensor involved in the regulated release of insulin, we have investigated the acute actions of novel glucokinase activator compound 50 (GKA50) on islet function. Insulin secretion was determined by enzyme-linked immunosorbent assay, and microfluorimetry with fura-2 was used to examine intracellular Ca(2+) homeostasis ([Ca(2+)](i)) in isolated mouse, rat, and h...

Pancreatic beta cells exhibit a remarkable ability to tune their secretory functions in response to altered tissue insulin demands. Glucose, nutrients (amino acids and lipids), neurohormonal signals and lipid mediators (i.e. free fatty acids, diacylglycerol, phosphatidic acid) all efficaciously modulate insulin secretion. Recently, the presence of a functional endocannabinoid (eCB) system (that...

An isocaloric low-protein (LP) diet (8% instead of 20% in controls) given to dams during gestation reduces the fractional insulin release of stimulated fetal islets. The LP diet lowers the plasma concentration of taurine in both pregnant rats and their fetuses. This study reports the effect of taurine on the in vitro release of insulin from control and LP fetal islets. Direct stimulation with t...

objective: the aim of this study was to evaluate the effect of exendin-4 (ex-4) on differentiation of insulin-producing cells (ipcs) from rat bone marrow-derived mesenchymal stem cells (rat-bm-mscs). materials and methods: in this experimental study, rat-bm-mscs were cultured and the cells characterized by flow cytometry analysis of cell surface markers. rat-bm-mscs were subsequently treated wi...

Secreted frizzled-related protein 5 (Sfrp5) is an adipokine with anti-inflammatory and insulin-sensitizing properties in mice. However, the mechanism of Sfrp5 action, especially in humans, is largely unknown. Therefore, cytokine release and insulin signaling were analyzed to investigate the impact of Sfrp5 on inflammation and insulin signaling in primary human adipocytes and skeletal muscle cel...