氟中毒对体外培养破骨细胞数量及骨吸收功能的影响

目的 观察氟中毒对体外培养破骨细胞数量及骨吸收功能的影响,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孔培养板和象牙片培养,而骨髓基质细胞接种于6孔培养板培养,分别于2 h后换液并染氟(氟化钠),对照组、低氟组、中氟组、高氟组染氟剂量分别为0、2.5×10-5、5.0×10-5、10.0×10-5mol/L.培养2、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,光镜下计数破骨细胞数量;培养5 d后象牙片经1%甲苯胺蓝染色,光镜下分析破骨细胞骨吸收陷窝面积.骨髓基质细胞染氟作用8 h后提取总RNA,实时荧光定量PCR法检测细胞核因子κβ受体活化因子配体(RANKL)和骨保护素(0PG)mRNA表达水平.结果 ①体外培养2 d时,对照组、低氟组、中氟组、高氟组破骨细胞数量分别为(337.5 4-70.5)、(447.5 ±43.4)、(472.9±34.8)、(475.3±24-3)个/孔,各染氟组明显高于对照组(P均<0.05);体外培养5 d时,对照组、低氟组、中氟组、高氟组破骨细胞数量分别为(92.5±22.1)、(123.0±26.4)、(135.5 ±22.2)、(136.9 ±23.0)个/孔,各染氟组明显高于对照组(P均<0.05).②体外培养5 d时,对照组、低氟组、中氟组、高氟组破骨细胞骨吸收陷窝面积分别为(0.088±0.030)、(0.100 ±0.018)、(0.152±0.015)、(0.242±0.031)mm2/片,中氟组和高氟组明显高于对照组(P均<0.05).③对照组、低氟组、中氟组、高氟组骨髓基质细胞RANKL/OPG mRNA表达比值分别为100.00±56.02、144.95±97.21、223.25 ±184.48、193.98 ±137.93,中氟组和高氟组明显高于对照组(P均<0.05).结论 氟中毒可引起体外培养破骨细胞数量增多,促进其细胞分化及骨吸收活性,该作用可能与其上调 RANKL/OPC,mRNA表达比值有关.

Abstract：

Objective To determine the effects of fluoride on osteoclasts's quantity and bone resorption function in vitro and 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. The osteoclasts were inoculated in 96-well culture plate and ivory slice, BMSCs were inoculated in 6- well culture plate, respectively, medium were changed after 2 hours incubation. They were divided into control group, low-dose fluoride, medium-dose fluoride and high-dose fluoride groups, the doses of sodium fluoride were 0,2.5 × 10-5,5.0 × 10-5,10.0 × 10-5 mol/L, respectively. Tartrate-resistant acid phosphatase(TRAP) staining positive cells were counted under light microscope after TRAP staining on the 2nd and the 5th day and the pit formed in ivory slices were measured by histomorphometry after staining with toludine blue. The expression of receptor activator of NK-κβ ligand(RANKL) and osteoprotegerin(OPC) was detected by real-time fluorescence quantitative (337.5 ± 70.5), (447.5 ± 43.4), (472.9 ± 34.8), (475.3 ± 24.3)/well in the control group, the low-dose, mediumdose and high-dose fluoride groups, respectively. The differences were statistically significant between these groups and the control group (all P < 0.05). After in vitro culture for 5 days, the numbers of osteoclasts were (92.5 ± 22.1), (123.0 ± 26.4), (135.5 ± 22.2), (136.9 ± 23.0) per well in the control group, the low-dose, medium-dose and high-dose fluoride groups, respectively. The differences were statistically significant between these groups and the (0.088 ± 0.030), (0.100 ± 0.018), (0.152 ± 0.015), (0.242 ± 0.031 )mm2 per piece in the control group, the lowdose, medium-dose and high-dose fluoride groups, respectively. The values of medium-dose and high-dose fluoride BMSCs in the control group, the low-dose, medium-dose and high-dose fluoride groups were 100.00 ± 56.02, 144.95 ± 97.21,223.25 ± 184.48,193.98 ± 137.93, respectively. The values of medium-dose and high-dose fluoride groups were significantly higher than that of control group (all P < 0.05). Conclusions Fluoride can cause increase in the number of osteoclasts in vitro and promote their cell differentiation and bone resorption activity, which may be related to increased expression ratio of RANKL/OPG mRNA in BMSCs.

Effects of fluorosis on osteoclasts's quantity and bone resorption function in vitro

Objective To determine the effects of fluoride on osteoclasts's quantity and bone resorption function in vitro and 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. The osteoclasts were inoculated in 96-well culture plate and ivory slice, BMSCs were inoculated in 6- well culture plate, respectively, medium were changed after 2 hours incubation. They were divided into control group, low-dose fluoride, medium-dose fluoride and high-dose fluoride groups, the doses of sodium fluoride were 0,2.5 × 10-5,5.0 × 10-5,10.0 × 10-5 mol/L, respectively. Tartrate-resistant acid phosphatase(TRAP) staining positive cells were counted under light microscope after TRAP staining on the 2nd and the 5th day and the pit formed in ivory slices were measured by histomorphometry after staining with toludine blue. The expression of receptor activator of NK-κβ ligand(RANKL) and osteoprotegerin(OPC) was detected by real-time fluorescence quantitative (337.5 ± 70.5), (447.5 ± 43.4), (472.9 ± 34.8), (475.3 ± 24.3)/well in the control group, the low-dose, mediumdose and high-dose fluoride groups, respectively. The differences were statistically significant between these groups and the control group (all P < 0.05). After in vitro culture for 5 days, the numbers of osteoclasts were (92.5 ± 22.1), (123.0 ± 26.4), (135.5 ± 22.2), (136.9 ± 23.0) per well in the control group, the low-dose, medium-dose and high-dose fluoride groups, respectively. The differences were statistically significant between these groups and the (0.088 ± 0.030), (0.100 ± 0.018), (0.152 ± 0.015), (0.242 ± 0.031 )mm2 per piece in the control group, the lowdose, medium-dose and high-dose fluoride groups, respectively. The values of medium-dose and high-dose fluoride BMSCs in the control group, the low-dose, medium-dose and high-dose fluoride groups were 100.00 ± 56.02, 144.95 ± 97.21,223.25 ± 184.48,193.98 ± 137.93, respectively. The values of medium-dose and high-dose fluoride groups were significantly higher than that of control group (all P < 0.05). Conclusions Fluoride can cause increase in the number of osteoclasts in vitro and promote their cell differentiation and bone resorption activity, which may be related to increased expression ratio of RANKL/OPG mRNA in BMSCs.