氟对体外培养绵羊成骨细胞Bcl-2和Bax基因表达的影响

Effects of fluoride on Bcl-2 and Bax gene expression in osteoblasts cultured in vitro

目的:探讨氟对体外培养成骨细胞凋亡相关基因Bcl-2和Bax基因表达的影响。方法:采用酶完全消化法分离2～3月龄胎羊颅盖骨成骨细胞,加入不同浓度(0～10-3mol/L)NaF,作用24h后,提取细胞总RNA并反转录成cDNA,通过实时荧光定量PCR方法,检测成骨细胞Bcl-2和Bax基因表达的变化。结果:1.0×10-5mol/LNaF组Bcl-2基因表达水平较对照组高,其他组Bcl-2表达水平均比对照组低;各NaF浓度组Bax基因表达量均比对照组高,且5.0×10-4mol/L组最高;除1.0×10-5mol/LNaF组外,Bcl-2/Bax比值均比对照组低,且5.0×10-4mol/L组最低。结论:高浓度NaF可能增加成骨细胞线粒体膜的通透性,下调Bcl-2 mRNA表达,上调Bax mRNA的表达,可能启动了线粒体凋亡信号转导途径。

The objective of this study was to evaluate the role of fluoride on bcl-2 and bax gene expressions in osteoblasts cultured in vitro. Osteoblasts were isolated from calvaria in embryo sheep of 2～3 months old and exposed to different dose of sodium fluoride （0～10-3mol/L） for 24 hours. RNA was extracted from osteoblasts cultured in vitro and bcl-2 and bax gene expression at different fluoride concentrations were detected by real-time fluorescent quantitative PCR. The results indicated that 1.0×10-5mol/L sodium fluoride treatment up-regulated bcl-2 gene expression,however,other treatments down-regulated bcl-2 gene expression; treatment of the cells with sodium fluoride （10-5～10-3mol/L） up-regulated the expression of bax gene. Furthermore,5.0×10-4 mol/L sodium fluoride treatment showed the highest expression; Bcl-2/Bax ratios were lower than the control except for 1.0×10-5mol/L sodium fluoride treatment,and 5.0×10-4 mol/L sodium fluoride treatment showed the lowest ratio. In conclusion,the results in the current study suggest that high dose of sodium fluoride may induce mitochondrial membrane depolarization,down-regulate the expression of bcl-2 mRNA and up-regulate the expression of bax mRNA expression in osteoblasts. Sodium fluoride may activate the mitochondrial apoptosis signal transduction pathway.