Metabolic syndrome (MS) may comprise several clinical conditions such as obesity, diabetes and inflammatory disorders, which are characterized by metabolic imbalances. The study of glucose transport and regulation by insulin in lymphocytes is important, since the way they increase inflammation and susceptibility to infections are common in MS. We studied glucose internalization in isolated thym...

Parathyroid hormone (PTH) and PTH-related peptide (PTHrP) binding to their common receptor stimulates second messenger accumulation, receptor phosphorylation, and internalization. LLC-PK(1) cells expressing a green fluorescent protein-tagged PTH/PTHrP receptor show time- and dose-dependent receptor internalization. The internalized receptors colocalize with clathrin-coated pits. Internalization...

Cell-surface-associated annexin A2 (CS-ANXA2) is a nonconventional "receptor" for progastrin; expression levels of both are elevated in colon cancers, and downregulation of either reduces tumorigenic potential of cells. We recently reported internalization of progastrin in target cells. Here, mechanisms mediating internalization of progastrin were examined. Initially, we confirmed that cell-sur...

The internalization of a basic peptide, 001-C8 [H-MeTyr-Arg-MeArg-d-Leu-NH(CH2)8NH2], into enterocyte-like Caco-2 cells was evaluated. Internalization of125I-labeled 001-C8 (125I-001-C8) increased time dependently and reached steady state at 60 min. The steady-state internalization of 125I-001-C8 (7.24 ± 0.41 μl/mg protein) was temperature and concentration dependent and was significantly decre...

The scope of this study was to analyze the relationship between the internalization of body image and depressive symptoms with restrictive eating habits among young males. Three hundred and eighty-three male adolescents, aged between twelve and seventeen, took part in this survey. The "Overall Internalization" and "Athletic Internalization" sub-scales taken from the Sociocultural Attitudes Towa...

We investigated the role of arrestins in the trafficking of human alpha2-adrenergic receptors (alpha2-ARs) and the effect of receptor trafficking on p42/p44 MAP kinase activation. alpha2-ARs expressed in COS-1 cells demonstrated a modest level of agonist-mediated internalization, with alpha2c > alpha2b > alpha2a. However, upon coexpression of arrestin-2 (beta-arrestin-1) or arrestin-3 (beta-arr...

Gonadotropin-releasing hormone (GnRH) acts via seven transmembrane receptors to stimulate gonadotropin secretion. Sustained stimulation desensitizes GnRH receptor (GnRHR)-mediated gonadotropin secretion, and this underlies agonist use in hormone-dependent cancers. Since type I mammalian GnRHR do not desensitize, agonist-induced internalization and downregulation may underlie desensitization of ...

Development of micro- and nanotechnology for the study of living cells, especially in the field of drug delivery, has gained interest in recent years. Although several studies have reported successful results in the internalization of micro- and nanoparticles in phagocytic cells, when nonphagocytic cells are used, the low internalization efficiency represents a limitation that needs to be overc...

Adenosine diphosphate (ADP) is a critical regulator of platelet activation, mediating its actions through two G protein-coupled receptors, the P2Y(1) and P2Y(12) purinoceptors. Recently, we demonstrated that P2Y(1) and P2Y(12) purinoceptor activities are rapidly and reversibly modulated in human platelets, revealing that the underlying mechanism requires receptor internalization and subsequent ...

The neonatal Fc receptor, FcRn mediates an endocytic salvage pathway that prevents degradation of IgG, thus contributing to the homeostasis of circulating IgG. Based on the low affinity of IgG for FcRn at neutral pH, internalization of IgG by endothelial cells is generally believed to occur via fluid-phase endocytosis. To investigate the role of FcRn in IgG internalization, we used quantitative...