Tubuloside B rescues the PC12 neuronal cells from H_2O_2-induced apoptosis / 中国病理生理杂志

ABSTRACT

AIM: To investigate the neuroprotective effect of tubuloside B,one of the phenylethanoids isolated from the stems of Cistanche salsa,on H2O2-induced injury in PC12 cells.METHODS: PC12 cells were exposed to various doses of tubuloside B for 12 h,then treated with H2O2 at concentration of 100 ?mol/L for 24 h.The cell viability was observed with MTT assay.Reactive oxygen species and the mitochondrial membrane potential were measured with laser scanning confocal microscopy(LSCM).The DNA content and percentage of apoptosis were assayed by DNA agarose gel electrophoresis and flow cytometry.The activation of caspase-3 was detected with the caspase-3 activity assay kit.RESULTS: Following treatment with H2O2 for 24 h,H2O2 induced a significant decrease in cell viability;DNA ladder was observed and apoptosis percentage was as high as 48.0%.Accumulation of intracellular ROS,increase in caspase-3 activity and the decrease in mitochondrial membrane potential as indicated with the decrease of red/green ratios(from 5.97 to 0.41) were detected.However,pretreatment with tubuloside B(1,10 or 100 mg?L-1) for 12 h exhibited cytoprotective effects in a dose-dependent manner.Tubuloside B obviously enhanced the cell viability,reduced formation of the DNA ladder,and significantly reduced the number of cells labeled with Annexin-V.The percentage of apoptosis/necrosis neurons was significantly decreased to 30.9%,18.3% and 6.2%,respectively.LSCM showed that the tubuloside B attenuated the accumulation of ROS and the H2O2-induced collapse of mitochondrial membrane potential in PC12 cells.The significant decrease in caspase-3 activity was detected,compared to the H2O2-treated cells at the same time point.CONCLUSION: Tubuloside B has the neuroprotective capacity to antagonize H2O2-induced apoptosis and injury in PC12 cells,indicating it may be useful for treating some neurodegenerative diseases.