氟铝及联合作用对体外培养大鼠破骨细胞数量及骨吸收功能的影响

摘要

目的 观察单纯氟、铝及氟铝联合作用对体外培养大鼠破骨细胞功能的影响,探讨其作用机制.方法 机械分离法作用于新生SD大鼠四肢长骨,于TC199培养液(含10％胎牛血清)中获得破骨细胞和骨髓基质细胞,将破骨细胞接种于96孔培养板和象牙薄切片培养,骨髓基质细胞接种于6孔培养板培养.2h后换液并染毒(氟化钠和氯化铝),分为对照组(氟化钠和氯化铝浓度均为0 mol/L)、氟组(氟化钠1.0×10-4 mol/L)、铝组(氯化铝1.0×10-5 mol/L)和氟铝联合组(氟化钠1.0×10-4 mol/L,氯化铝1.0×10-5 mol/L).培养5d后,对培养板中破骨细胞进行抗酒石酸酸性磷酸酶(TRAP)染色,光镜下检查破骨细胞数目;象牙薄切片经1％甲苯胺蓝染色,光镜下分析破骨细胞骨吸收陷窝面积.骨髓基质细胞染毒培养8h后提取总RNA,实时荧光PCR法测定骨保护素(OPG)和细胞核因子κβ受体活化因子配体(RANKL)的表达量水平.结果 ①氟、铝、氟和铝的交互作用对破骨细胞数量均有影响(F值分别为7.15、6.56、7.98,P均＜0.05),氟组、铝组及氟铝联合组破骨细胞数量[(136.9±22.99)、(135.4±23.5)、(163.0±24.4)个/孔]均高于对照组[(92.5±22.1)个/孔,P均＜0.05],氟铝联合组高于氟组和铝组(P均＜0.05).②氟组、铝组及氟铝联合组对破骨细胞骨吸收陷窝面积均有影响(F值分别为10.47、12.64、14.29,P均＜0.05),氟组、铝组及氟铝联合组骨吸收陷窝面积[(0.242±0.031)、(0.293±0.026)、(0.333±0.016)mm2/片]均高于对照组[(0.088±0.030)mm2/片,P均＜0.05],氟铝联合组高于氟组和铝组(P均＜ 0.05).③氟、铝、氟和铝的交互作用对RANKL/OPG mRNA表达量的比值均有影响(F值分别为8.15、15.38、23.59,P均＜0.05),氟组、铝组、氟铝联合组[(193.98±137.93)％、(326.11±176.78)％、(599.84±275.82)％]均高于对照组[(100.00±56.02)％,P均＜0.05],氟铝联合组高于氟组和铝组(P均＜0.05).结论 氟、铝均可引起体外培养破骨细胞数量增多,促进其分化、增强骨吸收活性,该作用可能与其上调RANKL/OPG mRNA表达量比值有关.同时,氟铝联合作用对破骨细胞活性的刺激有叠加效果.%Objective To determine the impact of fluorine and aluminum,and both action combined on the number of rat osteoclasts and bone resorption cultured in vitro and to explore its mechanisms.Methods The osteoclasts and bone marrow stromal cells (BMSCs) isolated from long bone of new born rats were cultured,respectively,in TC199 medium (containing 10％ fetal bovine serum) with fluoride,aluminum and fluoride combined with aluminum.The osteoclasts were inoculated in 96-well culture plate and ivory slice,BMSCs in 6-well culture plate,and culture medium was changed after 2 hours incubation.The cells were divided into control group,fluoride group,aluminum group and fluoride combined with aluminum group; the doses of sodium fluoride were 0,1.0 × 10-4,0,1.0 × 10-4 mol/L and the doses of aluminum chloride were 0,0,1.0 × 10-5,1.0 × 10-5 mol/L,respectively.Tartrate-resistant acid phosphatase (TRAP) staining positive cells were counted under light microscope after TRAP staining on the 5th day and the pit formed in ivory slices were measured by histomorphometry after staining with toludine blue.The expression of osteoprotegerin(OPG) and receptor activator of nuclear factor kappa-B ligand (RANKL) was detected by real-time fluorescence quantitative PCR in BMSCs after 8 h treatment.Results ① Fluoride,aluminum and the interactive effects of fluoride and aluminum all had impact on the numbers of osteoclasts (F =7.15,6.56 and 7.98,respectively,all P ＜ 0.05).The numbers of osteoclasts in fluoride group,aluminum group and fluoride combined with aluminum group[(136.9 ± 22.99),(135.4 ± 23.5),(163.0 ± 24.4) per well] were higher than that in the control group[(92.5 ± 22.1) per well,all P ＜ 0.05].② Fluoride,aluminum and the interactive effects of fluoride and aluminum all had impact on the resorption pit area on ivory slices(F =10.47,12.64,14.29,respectively,all P ＜ 0.05).The resorption pit area on ivory slices in fluoride group,aluminum group and fluoride combined with aluminum group[(0.242 ± 0.031),(0.293 ± 0.026),(0.333 ± 0.016)mm2 per slice] was higher than that in the control group [(0.088 ± 0.030)mm2 per slice,all P ＜ 0.05].③Fluoride,aluminum and the interactive effects of fluoride and aluminum all had impact on the expression ratios of RANKL/OPG in BMSCs (F =8.15,15.38,23.59,respectively,all P ＜ 0.05).The expression ratios of RANKL/OPG in BMSCs in fluoride group,aluminum group and fluoride combined with aluminum group [(193.98 ± 137.93)％,(326.11 ± 176.78)％,(599.84 ± 275.82)％] were higher than that in the control group[(100.00 ± 56.02)％,all P ＜ 0.05].Conclusions Both fluoride and aluminum can cause increase in the number of osteoclasts in vitro and promote cell differentiation and bone resorption activity,which may be related to increased expression ratio of RANKL/OPG mRNA in BMSCs.The stimulating effects of fluoride on osteoclasts differentiation and bone resorption is enhanced by aluminum.