Open AccessRole of Microtubules in Glucose Uptake by C6 Glioma Cells
Author(s) -
Singh Sant P.,
Gao Yan,
Singh Leela D.,
Kunapuli S. P.,
Ravindra Rudravajhala
Publication year - 1998
Publication title -
pharmacology & toxicology
Language(s) - English
Resource type - Journals
eISSN - 1600-0773
pISSN - 0901-9928
DOI - 10.1111/j.1600-0773.1998.tb01448.x
Subject(s) - colchicine , hexose , tubulin , glucose uptake , microtubule , paclitaxel , biochemistry , microtubule polymerization , glut1 , carbachol , glucose transporter type 1 , biology , microbiology and biotechnology , chemistry , endocrinology , receptor , insulin , enzyme , genetics , chemotherapy
Drugs that influence tubulin function were used to investigate the role of microtubules in hexose uptake by C6 glioma cells. In C6 cells, colchicine and vinblastine (which inhibit tubulin polymerization) inhibited radioactive [ 3 H]2‐deoxy‐D‐glucose uptake by about 30%. Paclitaxel (which promotes tubulin polymerization) stimulated hexose uptake by about 25%. To further demonstrate that microtubules play a role in hexose uptake, C6 cells were transfected with GLUT1 cDNA and then challenged with 100 nM paclitaxel. In GLUT1‐ transfected cells paclitaxel stimulated 2‐deoxy‐D‐glucose uptake by about 35%. To study the role of tubulin in agonist‐stimulated hexose uptake, the effect of colchicine on carbach‐ol‐induced uptake was next examined. Hexose uptake was increased with carbachol in concentration‐dependent manner which was abolished by pretreatment with colchicine. To examine the specificity of the inhibitory effect of colchicine on G protein‐mediated signal transduction pathway, the influence of colchicine on insulin (which acts via tyrosine kinase pathway) stimulation of 2‐deoxy‐D‐glucose uptake was investigated. Hexose uptake was increased by insulin in a concentration‐dependent manner which was unaffected by pretreatment with colchicine. These results suggest that microtubules are involved in basal and carbachol‐stimulated glucose uptake by C6 cells.