New methods for the analysis of glucose transporters were used to analyze the molecular mechanisms involved in the insulin-antagonistic effects of growth hormone (GH), which is known as a diabetogenic hormone. The ability of GH to alter the number and mRNA levels of two different glucose transporters in cultured 3T3-F442A adipocytes was investigated using specific antibodies and cDNA probes. At...

Objective(s):This study examined whether conjugated linoleic acid (CLA) supplementation affects insulin sensitivity and peroxisome proliferator-activated receptor gamma (PPAR-γ) and glucose transporter type 4 (GLUT-4) protein expressions in the skeletal muscles of rats during endurance exercise. Materials and Methods:Sprague-Dawley male rats were randomly divided into HS (high-fat diet (HFD) s...

The relationships among fiber type, glucose transporter (GLUT-4) protein content, and glucose transport activity stimulated maximally with insulin and/or contractile activity were studied by use of the rat epitrochlearis (15% type I-20% type II2a-65% type IIb), soleus (84-16-0%), extensor digitorum longus (EDL, 3-57-40%), and flexor digitorum brevis (FDB, 7-92-1%) muscles. Insulin-stimulated 2-...

Thomas-Delloye, Véronique, Florence Marmonier, Claude Duchamp, Béatrice Pichon-Georges, Joël Lachuer, Hervé Barré, and Gabriel Crouzoulon. Biochemical and functional evidences for a GLUT-4 homologous protein in avian skeletal muscle. Am. J. Physiol. 277 (Regulatory Integrative Comp. Physiol. 46): R1733–R1740, 1999.—The characteristics and modulation of glucose transport were investigated in ske...

We examined the effect of acute exercise on muscle glucose transporter (GLUT-4) protein and mRNA concentrations in nine male type 1 diabetic patients (age 31 +/- 3 yr, body mass index 23.6 +/- 0.7 kg/m2, insulin dose 44 +/- 4 U/day, glycosylated hemoglobin 7.8 +/- 0.4%) and in nine healthy control subjects (34 +/- 1 yr, 25.3 +/- 0.8 kg/m2). Three hours of cycle ergometer exercise was performed ...

To elucidate the possible role of the mitochondrial uncoupling protein (UCP)-3 in skeletal muscle as a regulator of adaptive thermogenesis and energy balance, we examined the modulation by cold exposure (5°C) of UCP-3 and glucose transporter isoform GLUT-4 mRNAs in male Sprague-Dawley rats. In skeletal muscle, UCP-3 and GLUT-4 mRNAs increased two- to threefold between 6 and 24 h of cold exposur...

Background It is well known that cancer cells display increased glucose uptake and consumption [1]. In a rate-limiting step for glucose metabolism, the glucose transporter (GLUT) proteins facilitate glucose uptake across the plasma membrane. In human cells, 14 different GLUT (1-14) isoforms have been discovered. Of these, GLUT1, 3 and 4 have been extensively studied while the more recently disc...

In preconditioned myocardium, activation of the mitogen-activated protein kinase (MAPK) p38 leads to increased glucose uptake via enhanced GLUT-4 translocation. Glucose uptake is also increased in chronic hibernating myocardium, but the role of p38 MAPK and GLUT-4 translocation has not been studied. Nine swine underwent instrumentation of the proximal left anterior descending coronary artery (L...