The Experts below are selected from a list of 81 Experts worldwide ranked by ideXlab platform

Huang Hong - One of the best experts on this subject based on the ideXlab platform.

Michael V. Berridge - One of the best experts on this subject based on the ideXlab platform.

  • The Hemopoietic Growth Factor, Interleukin-3, Promotes Glucose Transport by Increasing the Specific Activity and Maintaining the Affinity for Glucose of Plasma Membrane Glucose Transporters
    The Journal of biological chemistry, 1997
    Co-Authors: Kathy D. Mccoy, Nuzhat Ahmed, An S. Tan, Michael V. Berridge
    Abstract:

    Abstract Most mammalian cells rely on an external supply of glucose for survival, proliferation, and function. Glucose enters cells through specific transporter molecules at the plasma membrane by a facilitative process that does not expend energy. Regulation of glucose transport into cells is thought to occur largely through transporter expression at the cell surface, but the extent to which the intrinsic properties of glucose transporters are regulated is at present controversial. Using a bone marrow-derived cell line that responds to the Hemopoietic Growth Factor, interleukin-3 (IL-3), we investigated IL-3 regulation of glucose transport. IL-3 significantly increased 2-deoxyglucose (2-DOG) uptake within 1 h (26 ± 8.0%, n = 11) with a maximum 73% increase after 6 h. Withdrawal of IL-3 resulted in decreased uptake within 1 h and this continued to decline to 43% of initial uptake by 16 h. To determine whether these changes in 2-DOG uptake were associated with corresponding changes in glucose transporter expression, subtype-specific antisera against Glut-1 and Glut-3 were used. Little change in membrane expression of these transporters was observed prior to 16 h. Fractionation of cell membranes on Nycodenz gradients showed that the majority of each transporter subtype was associated with the plasma membrane (63–93%) and that transporter distribution did not change markedly in response to addition or withdrawal of IL-3. These results demonstrate that IL-3 regulates glucose uptake by modulating the intrinsic transporting ability of glucose transporters. Decreased transporter affinity for 2-DOG and 3-O-methylglucose was observed following IL-3 withdrawal. Similar affinity changes were observed with 2-DOG following exposure of IL-3-stimulated cells to the protein kinase inhibitors, genistein and staurosporine. In contrast, the tyrosine phosphatase inhibitor, vanadate, acted like IL-3 to increase transporter affinity for glucose. Together these results demonstrate that IL-3 acts to maintain the intrinsic transport properties of glucose transporters without markedly affecting their expression or translocation.

M.c. De Vernejoul - One of the best experts on this subject based on the ideXlab platform.

Albertus W Wognum - One of the best experts on this subject based on the ideXlab platform.

  • surface markers and Growth Factor receptors of immature Hemopoietic stem cell subsets
    Stem Cells, 1995
    Co-Authors: Gerard Wagemaker, Karen J Neelis, Albertus W Wognum
    Abstract:

    The regenerative potential of bone marrow following exposure to relatively high doses of ionizing radiation, as well as the efficacy of Hemopoietic Growth Factor treatment, are dependent on the residual number of Hemopoietic stem cells. From studies in mice in particular, evidence has been obtained that immature Hemopoietic stem cells are heterogenous with respect to repopulating capacity, with one subset being capable of short-term, transient Hemopoietic reconstitution and another subset of sustained reconstitution. In rhesus monkeys, CD34+, RhLA-DRdull cells were identified as the small fraction of a bone marrow cell that contains reconstituting Hemopoietic stem cells. The Growth Factor receptor phenotype of this immature cell fraction has been determined for granulocyte-macrophage colony-stimulating Factor (GM-CSF), interleukin 3 (IL-3), and IL-6 as well as for kit-ligand, making c-kit an especially strong Growth Factor receptor marker for reconstituting stem cells. In addition, it is demonstrated that CD34+ cells appear in peripheral blood after exposure to radiation and are correlated to numbers of CD34+ cells in bone marrow. This finding suggests that circulating CD34+ cells may be used as a cellular marker with prognostic significance for both the number of residual stem cells as well as regeneration of immature Hemopoietic cells in bone marrow.

Kathy D. Mccoy - One of the best experts on this subject based on the ideXlab platform.

  • The Hemopoietic Growth Factor, Interleukin-3, Promotes Glucose Transport by Increasing the Specific Activity and Maintaining the Affinity for Glucose of Plasma Membrane Glucose Transporters
    The Journal of biological chemistry, 1997
    Co-Authors: Kathy D. Mccoy, Nuzhat Ahmed, An S. Tan, Michael V. Berridge
    Abstract:

    Abstract Most mammalian cells rely on an external supply of glucose for survival, proliferation, and function. Glucose enters cells through specific transporter molecules at the plasma membrane by a facilitative process that does not expend energy. Regulation of glucose transport into cells is thought to occur largely through transporter expression at the cell surface, but the extent to which the intrinsic properties of glucose transporters are regulated is at present controversial. Using a bone marrow-derived cell line that responds to the Hemopoietic Growth Factor, interleukin-3 (IL-3), we investigated IL-3 regulation of glucose transport. IL-3 significantly increased 2-deoxyglucose (2-DOG) uptake within 1 h (26 ± 8.0%, n = 11) with a maximum 73% increase after 6 h. Withdrawal of IL-3 resulted in decreased uptake within 1 h and this continued to decline to 43% of initial uptake by 16 h. To determine whether these changes in 2-DOG uptake were associated with corresponding changes in glucose transporter expression, subtype-specific antisera against Glut-1 and Glut-3 were used. Little change in membrane expression of these transporters was observed prior to 16 h. Fractionation of cell membranes on Nycodenz gradients showed that the majority of each transporter subtype was associated with the plasma membrane (63–93%) and that transporter distribution did not change markedly in response to addition or withdrawal of IL-3. These results demonstrate that IL-3 regulates glucose uptake by modulating the intrinsic transporting ability of glucose transporters. Decreased transporter affinity for 2-DOG and 3-O-methylglucose was observed following IL-3 withdrawal. Similar affinity changes were observed with 2-DOG following exposure of IL-3-stimulated cells to the protein kinase inhibitors, genistein and staurosporine. In contrast, the tyrosine phosphatase inhibitor, vanadate, acted like IL-3 to increase transporter affinity for glucose. Together these results demonstrate that IL-3 acts to maintain the intrinsic transport properties of glucose transporters without markedly affecting their expression or translocation.