Unknown

T17 cells stably transfected with rat TrkA ere cultured in DMEM containing 1 mM pyruvate and 10% FBS at 37 deg-C under a 5% CO2 atmosphere and including 300 micro-g/mL G418. T17 cells were seeded in 96 well plates at 10,000 cells per well in 100 microL of complete medium. Cells were incubated overnight, followed by 30-minutes pretreatment with 10 microM of dimethyl-Gambogic acid in DMSO. Cells were then treated with 1 microM staurosporine for 9 hours. One hour before the termination of the experiment a cell-permeant caspase-3-activated dye was introduced (10 micro-M MR(DEVD)2). Cells wee fixed, washed and examined by fluorescence microscopy. Dimethyl-Gambogic acid suppressed apoptosis in T17 cells and exhibited a protective effect n TrkB-stable cells indicating that apoptotic machinery is blocked independent of Trk receptors. The EC50 for dimethyl-Gambogic acid on T17 cells is reported as 120 nano-M.