Modulation of glucose transporters in rat diaphragm by sodium tungstate.
Oral administration of sodium tungstate is an effective treatment for diabetes in animal models. We examined the effects of 6 weeks of oral administration of tungstate on glucose transporters (GLUT) in streptozotocin-induced diabetic rat diaphragm. Diabetes decreased GLUT4 expression while tungstate treatment normalized not only GLUT4 protein but also GLUT4 mRNA in the diabetic rats. Furthermore, treatment increased GLUT4 protein in plasma and internal membranes, suggesting a stimulation of its translocation to the plasma membrane. Tungstate had no effect on healthy animals. There were no differences in the total amount of GLUT1 transporter in any group. We conclude that the normoglycemic effect of tungstate may be partly due to a normalization of the levels and subcellular localization of GLUT4, which should result in an increase in muscle glucose uptake.
Department of Biochemistry and Molecular Biology, School of Pharmacy, University of Granada, Campus de Cartuja sn, E-18071 Granada, Spain.
M D
MD
Girón
J J
JJ
Caballero
A M
AM
Vargas
M D
MD
Suárez
J J
JJ
Guinovart
R
R
Salto
D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D002462:Cell Membrane / Q000737:chemistry; D003921:Diabetes Mellitus, Experimental / Q000175:diagnosis / Q000378:metabolism*; D003964:Diaphragm / Q000187:drug effects* / Q000378:metabolism; D005260:Female; D051272:Glucose Transporter Type 1; D051275:Glucose Transporter Type 4; D009004:Monosaccharide Transport Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D009124:Muscle Proteins; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D017208:Rats, Wistar; D017973:Tungsten Compounds / Q000494:pharmacology*
D001786:Blood Glucose; D051272:Glucose Transporter Type 1; D051275:Glucose Transporter Type 4; D009004:Monosaccharide Transport Proteins; D009124:Muscle Proteins; D012333:RNA, Messenger; C495679:Slc2a1 protein, rat; C495694:Slc2a4 protein, rat; D017973:Tungsten Compounds; C025399:sodium tungstate(VI)