【摘要】 目的研究氟化钠(NaF)对人成骨样细胞株凋亡的影响及其机制。方法四甲基偶氮噻唑蓝(MTT)法测定细胞的增殖能力,萤光染剂(Hoechst 33342)染色,DNA梯形(DNA Ladder)琼脂糖电泳,流式细胞仪分析检测细胞凋亡,RT-PCR半定量分析抗凋亡蛋白Bcl-2和促凋亡蛋白Bax mRNA表达,显色法检测凋亡相关激酶半胱氨酸蛋白酶3(Caspase-3)的活性。结果NaF(4,6,8×10-3mol/L)可以剂量依赖性地抑制细胞增殖(P<0.01),Hoechst33342染色、琼脂糖电泳和流式细胞仪均可检测到氟对成骨细胞凋亡的诱导作用。RT-PCR结果显示:NaF可以剂量依赖性地抑制Bcl-2 mRNA表达(P<0.01),提高Bax mRNA表达(P<0.01),并显著增强Caspase-3的活性(P<0.01)。结论NaF可以显著的抑制人成骨样细胞株增殖和诱导其凋亡,并可能是通过抑制Bcl-2表达,促进Bax表达和提高Caspase-3活性来诱导人成骨样细胞株凋亡。更多还原

【Abstract】 Objective To study the apoptotic effect of sodium fluoride（NaF） and its mechanisms in human osteoblast cell line OS-732.Methods The effects of NaF on osteoblast cell proliferation and apoptosis were detected by methyl thiazolyl tetrazolium（MTT）,Hoechst33342 fluorescence staining,agarose gel electrophoresis,flow cytometry（FCM）,semi-quantitative RT-PCR and caspase-3 activity assays.Results After cells were treated with NaF(4,6,8×10^-3?mol/L)for 24?h,the proliferation of OS-732 cells measured by MTT methods was inhibited in a dose dependent manner（P<0.01）.The morphological changes and the apoptotic peaks were observed by fluorescence staining and FCM respectively.In addition,the expression of Bcl-2 mRNA decreased whereas the expression of Bax mRNA increased measured by semi-quantitative RT-PCR.The activity of Caspase-3 also increased after cells were treated with NaF(6×10^-3?mol/L)for 24h（P<0.01）.Finally,DNA fragmentation was observed when cells were treated with NaF(4,6,8×10^-3?mol/L)for 48?h.Conclusion NaF inhibited the proliferation of osteoblast cell line OS-732 and induced the cells to undergo apoptosis by increasing the activity of caspase-3,and the expression of Bax while decreasing the expression of Bcl-2.更多还原