Fusion of GLUT4 vesicles with the plasma membrane is a key terminal step in insulin-regulated glucose transport. This fusion event is mediated by SNARE proteins, syntaxin 4, SNAP23 and VAMP2, through a process regulated by accessory proteins whose roles are still unclear. Munc18c is a key regulatory protein of syntaxin, and possibly of whole-SNARE complex cycling. Rab GTPases, through interacti...

Several gastrointestinal proteins have been identified to have insulinotropic effects, including glucose-dependent insulinotropic polypeptide (GIP); however, the direct effects of incretins on skeletal muscle glucose transport remain largely unknown. Therefore, the purpose of the current study was to examine the role of GIP on skeletal muscle glucose transport and insulin signaling in rats. Rel...

Most of the transport along the nephron uses membrane proteins and exhibits the three characteristics of mediated transport: saturation, specificity, and competition. Glucose reabsorption in the nephron is an excellent example of the consequences of saturation. Two classic papers by James A. Shannon and colleagues clearly show the ability of the kidney in transporting glucose and its saturation...

BACKGROUND The essential role of glucose transporter 2 (GLUT2) in glucose homeostasis has been extensively studied in mammals; however, little is known about this important protein in lower vertebrates. The freeze-tolerant wood frog (Rana sylvatica), which copiously mobilizes glucose in response to freezing, represents an excellent system for the study of glucose transport in amphibians. METH...

Background: Oleuropein, the main constituent of olive fruit and leaves, has been reported to protect against insulin resistance and diabetes. While many experimental investigations have examined the mechanisms by which oleuropein improves insulin resistance and diabetes, much of these investigations have been carried out in either muscle cell lines or in vivo models two scenarios with many draw...

The ability to take up and metabolize glucose at the cellular level is a property shared by the vast majority of existing organisms. Most mammalian cells import glucose by a process of facilitative diffusion mediated by members of the Glut (SLC2A) family of membrane transport proteins. Fourteen Glut proteins are expressed in the human and they include transporters for substrates other than gluc...

The developmental changes in the capacity for D-glucose transport of guinea pig erythrocyte membranes were compared to alterations in the electrophoretic pattern of erythrocyte membrane components. Guinea pig erythrocytes lose their D-glucose carrier functions during development. Good correlation was observed between the loss of glucose uptake and apparent decrease of the zone 4.5 of Coomassie ...

Chronic (24 h) insulin treatment and/or glucose deprivation of differentiated rat L6 skeletal muscle cells resulted in an increase in glucose transport activity and a 2-3-fold increase in the number of plasma membrane-associated cytochalasin B binding sites and immunoreactive glucose transporters. In contrast to the acute effect of insulin, chronic treatment did not decrease the number of cytoc...