Exercise-induced hyperinsulinism (EIHI) is an autosomal dominant disorder characterized by inappropriate insulin secretion in response to vigorous physical exercise or pyruvate injection. Activating mutations in the monocarboxylate transporter-1 (MCT1, SLC16A1) promoter have been linked to EIHI. Expression of this pyruvate transporter is specifically repressed (disallowed) in pancreatic β-cells...

Background: “Teucrium polium L.” (TP) has been long recommended in Iranian folk medicine for its anti-diabetic activities. We attempt here to evaluate the effect of TP extract on insulin secretion in rat pancreas. Methods: Rat pancreas was isolated in situ and perfused with Krebs solution containing low glucose (LG, 2.8 mM) or high glucose (HG, 16.7 mM) as perfusate. The aqueous extract (Aq. E)...

Stimulation of insulin secretion by glucose and other secretagogues from pancreatic islet beta-cells is mediated by multiple signaling pathways. Rac1 is a member of Rho family GTPases regulating cytoskeletal organization, and recent evidence also implicates Rac1 in exocytotic processes. Herein, we report that exposure of insulin-secreting (INS) cells to stimulatory glucose concentrations caused...

Abstract Reactive oxygen species and oxidative stress impair β-cell function and reduce insulin secretion. It has been shown that progesterone and cilostazol possess antioxidant properties. The present study was aimed to investigate in vitro pretreatment effect of progesterone and cilostazol on insulin secretion as well as their protective effects against hydrogen peroxide-induced oxidative str...

Introduction: The effect of esophageal distension (ED) on gastric motility has been well documented, but a few investigations have been carried out on the effect of ED on gastric secretion. The aim of this study was to investigate the effect of ED on gastric acid and pepsin secretion and the mechanism(s) involved. Methods: Male adult Wistar rats (200-240 g) were anesthetized with urethane (1...

MicroRNAs (miRNAs) have been implicated in a variety of physiological processes, however, the function of miRNAs in insulin secretion and type 2 diabetes is still unclear. Stxbp1 plays an essential role in exocytosis, and is crucial for insulin secretion. In this study, we focused on the molecular mechanism of Stxbp1 in insulin secretion by identifying its upstream regulators: miR-218 and miR-3...

background: the hepatic secretion of apolipoprotein b (apob), containing lipoproteins, is known to be regulated by insulin, and the overproduction of these atherogenic lipoproteins occurs in insulin-resistant states. protein tyrosine phosphatase 1b (ptp-1b) is a key regulator of hepatic insulin signaling and is also upregulated in insulin resistance. we aimed to investigate the role of ptp-1b i...

To evaluate the role of TCF7L2, a key regulator of glucose homeostasis, in estradiol (E2) and progesterone (P4)-modulated glucose metabolism, mouse insulinoma cells (MIN6) and human liver cancer cells (hepG2 and HUH7) were treated with physiological concentrations of E2 or P4 in the up- and down-regulation of TCF7L2. Insulin/proinsulin secretion was measured in MIN6 cells, while glucose uptake ...

The importance of the insulin receptor (IR) and the insulin-like growth factor-1 receptor (IGF-1R) for glucose-regulated insulin secretion and gene expression in pancreatic islet beta-cells is at present unresolved. Here, we have used small interfering RNAs (siRNAs) to silence the expression of each receptor selectively in clonal MIN6 beta-cells. Reduction of IR levels by >90% completely inhibi...

The importance of insulin for the in vivo effects of growth hormone (GH) on lipid and lipoprotein metabolism was investigated by examining the effects of GH treatment of hypophysectomized (Hx) female rats with and without concomitant insulin treatment. Hypophysectomy-induced changes of HDL, apolipoprotein (apo)E, LDL, and apoB levels were normalized by GH treatment but not affected by insulin t...