The apoptosis-inducing effect of a-anordrin (ANO)was investigated in this study. ANO 10-50 AM inhibited the growth of both human leukemia HL-60 and K562cells by 19-52%. Electron microscopy showed that ANO-treated cell...The apoptosis-inducing effect of a-anordrin (ANO)was investigated in this study. ANO 10-50 AM inhibited the growth of both human leukemia HL-60 and K562cells by 19-52%. Electron microscopy showed that ANO-treated cells exhibited the drastic changes including cell shrinkage, chromatin condensation, nuclear fragmentation, typical of apoptosis. Gel electrophoresis of DNA extracted farm botlt HL-60 and K562 cells treated with ANO revealed characteristic 'ladder' pattern.ANO 50 μM for 48 h caused approximately 50-70%apoptosis. Cycloheximide (CHX) and actinomycin D (Act D) did not prevent ANO-induced apoptosis in K562cells, however, apoptosis of HL-60 cells in the presence of ANO was partially blocked by these two agents.Moreover, it was found that tamoxifen synergically potcntiated and cstradiol partially antagonized ANOinduccd apoptosis in HL-60 cells. Results demonstrated that ANO could induce tumor cell apoptosis, which might contribute to its anticancer action.展开更多
To clarify the possible mechanisms of α anordin and probimane on calmodulin Ca ++ Mg ++ APTase system, enzyme dynamic study was carried out by determining three dynamic parameters [the substrate concentra...To clarify the possible mechanisms of α anordin and probimane on calmodulin Ca ++ Mg ++ APTase system, enzyme dynamic study was carried out by determining three dynamic parameters [the substrate concentration(ATP) response curve, dose(inhibitors) response curve and time response curve]. Our data have shown that the inhibitory rates of α anordrin and probimane are unrelated to substrate(APT) concentrations, but related to calmodulin concentrations. The inhibition of α anordrin and probimane is very quick that is completed within 1 to 5 min and can maintain more than 1 hr in the same inhibitory rates. So it is possible that α anordrin and probimane are calmodulin competitors with calmodulin like binding whose actions can occur by affecting the reaction balance of substrate and product on target enzymes of calmodulin( Ca ++ Mg ++ ATPase).展开更多
文摘The apoptosis-inducing effect of a-anordrin (ANO)was investigated in this study. ANO 10-50 AM inhibited the growth of both human leukemia HL-60 and K562cells by 19-52%. Electron microscopy showed that ANO-treated cells exhibited the drastic changes including cell shrinkage, chromatin condensation, nuclear fragmentation, typical of apoptosis. Gel electrophoresis of DNA extracted farm botlt HL-60 and K562 cells treated with ANO revealed characteristic 'ladder' pattern.ANO 50 μM for 48 h caused approximately 50-70%apoptosis. Cycloheximide (CHX) and actinomycin D (Act D) did not prevent ANO-induced apoptosis in K562cells, however, apoptosis of HL-60 cells in the presence of ANO was partially blocked by these two agents.Moreover, it was found that tamoxifen synergically potcntiated and cstradiol partially antagonized ANOinduccd apoptosis in HL-60 cells. Results demonstrated that ANO could induce tumor cell apoptosis, which might contribute to its anticancer action.
文摘To clarify the possible mechanisms of α anordin and probimane on calmodulin Ca ++ Mg ++ APTase system, enzyme dynamic study was carried out by determining three dynamic parameters [the substrate concentration(ATP) response curve, dose(inhibitors) response curve and time response curve]. Our data have shown that the inhibitory rates of α anordrin and probimane are unrelated to substrate(APT) concentrations, but related to calmodulin concentrations. The inhibition of α anordrin and probimane is very quick that is completed within 1 to 5 min and can maintain more than 1 hr in the same inhibitory rates. So it is possible that α anordrin and probimane are calmodulin competitors with calmodulin like binding whose actions can occur by affecting the reaction balance of substrate and product on target enzymes of calmodulin( Ca ++ Mg ++ ATPase).