Search Results - (Author, Cooperation:B. B. Kahn)

2014-04-11

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

Acetyltransferases/metabolism ; Adipocytes/metabolism/secretion ; Adipose Tissue/enzymology/metabolism ; Adipose Tissue, White/enzymology/metabolism ; Animals ; Diabetes Mellitus, Type 2/enzymology/metabolism ; *Diet ; Energy Metabolism ; Fatty Liver ; Gene Knockdown Techniques ; Glucose Intolerance ; Glucose Transporter Type 4/deficiency/genetics/metabolism ; Insulin Resistance ; Liver/enzymology ; Male ; Mice ; Mice, Inbred C57BL ; NAD/metabolism ; Niacinamide/metabolism ; Nicotinamide N-Methyltransferase/*deficiency/genetics/*metabolism ; Obesity/*enzymology/etiology/genetics/*prevention & control ; Ornithine Decarboxylase/metabolism ; Oxidoreductases Acting on CH-NH Group Donors/metabolism ; S-Adenosylmethionine/metabolism ; Sirtuin 1/metabolism ; Spermine/analogs & derivatives/metabolism ; Thinness/enzymology/metabolism

2012-04-03

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

Adipocytes/metabolism ; Adipose Tissue/cytology/*metabolism/pathology ; Adiposity ; Animals ; Basic Helix-Loop-Helix Leucine Zipper Transcription ; Factors/chemistry/genetics/*metabolism ; Blood Glucose/metabolism ; Body Mass Index ; Body Weight ; Cells, Cultured ; Cohort Studies ; Cross-Sectional Studies ; Diabetes Mellitus/blood/genetics/metabolism ; Female ; Gene Expression Regulation/genetics ; Genotype ; Glucose/*metabolism/pharmacology ; Glucose Intolerance/genetics ; Glucose Transporter Type 4/biosynthesis/genetics/metabolism ; Homeostasis/genetics ; Humans ; Insulin/metabolism/pharmacology ; Insulin Resistance/genetics ; Lipogenesis ; Male ; Mice ; Mice, Knockout ; Molecular Sequence Data ; Nuclear Proteins/chemistry/deficiency/genetics/*metabolism ; Obesity/genetics/metabolism ; Promoter Regions, Genetic/genetics ; Protein Isoforms/chemistry/genetics/metabolism ; RNA, Messenger/genetics/metabolism ; Transcription Factors/chemistry/deficiency/genetics/*metabolism

1432-0428

Glucose transport ; brain-type transporter ; diabetes mellitus

Springer Online Journal Archives 1860-2000

Medicine

Summary Northern blot analysis of human tissues has demonstrated the expression of the brain-type glucose transporter isoform (GLUT 3) in liver, muscle and fat, raising the possibility that this transporter isoform may play a role in the regulation of glucose disposal in these tissues in response to insulin. We have raised an anti-peptide antibody against the C-terminal 13 amino acids of the murine homologue of this transporter isoform, and determined its tissue distribution in mouse tissues and murine-derived cell lines. The antibodies recognise a glycoprotein of about 50 kilodaltons, expressed at high levels in murine brain. In contrast to human tissues, the expression of GLUT 3 in mice is restricted to the brain, and no immunoreactivity was observed in either liver, fat or muscle membranes, or in murine 3T3-L1 fibroblasts or adipocytes. In contrast, high levels of expression of this isoform were observed in the NG 108 neuroblastoma x glioma cell line, a hybrid cell derived from rat glioma and mouse neuroblastoma cells. Taken together, these data suggest that the expression of GLUT 3 in rodents is restricted to non-insulin responsive neuronal cells and hence it is likely that the factors regulating the expression of this transporter in rodents differ to those in humans.

Electronic Resource

1432-0428

KeywordsPPP1R3, PP1G, codon 905 polymorphism, Type II diabetes, glycogen synthesis, non-oxidative glucose metabolism, L6 myotubes, adenovirus.

Springer Online Journal Archives 1860-2000

Medicine

Abstract Aims/hypothesis. The glycogen-associated protein phosphatase-1 (PP1G) is thought to play an important part in the regulation of skeletal muscle glycogen content. We have previously identified an Asp905Tyr polymorphism of the glycogen-associated regulatory subunit of the protein phosphatase 1 (PPP1R3) gene which among healthy subjects was associated with decreased insulin stimulated non-oxidative glucose metabolism, i. e. primary glycogen synthesis. In this study, the functional effect of the polymorphism was examined in vitro.¶Methods. Wild type (PPP1R3-Asp905) and mutant (PPP1R3-Tyr905) PPP1R3 were expressed in L6 myotubes using adenovirus-mediated gene transfer. Basal and insulin-stimulated glucose uptake and glycogen synthesis were measured. Furthermore, the sensitivity of glycogen synthesis to a cyclic AMP agonist was measured.¶Results. Compared with green fluorescent protein-transduced myotubes and non-transduced myotubes, overexpression of PPP1R3-Asp905 and PPP1R3-Tyr905 increased both basal and insulin-stimulated glycogen synthesis approximately twofold. Treatment of both non-transduced and PPP1R3-transduced L6 myotubes with a cAMP agonist decreased both basal and insulin-stimulated glycogen synthesis by about 40 %. Overexpression of PPP1R3 did not affect either basal or insulin-stimulated 2-deoxy-d-glucose uptake compared with green fluorescent protein-transduced cells.¶Conclusion/interpretation. Results obtained from L6 myotubes transduced with PPP1R3-Asp905 or PPP1R3-Tyr905 showed no statistically significant difference. Therefore, the Asp905Tyr variant alone is unlikely to account for the decreased insulin stimulated non-oxidative glucose metabolism observed in the human study reported previously. [Diabetologia (2000) 43: 718–722]

Electronic Resource