过量氟引起成骨细胞内质网应激信号通路的基因差异表达

Genes differentially expression of endoplasmic reticulum stress signaling pathway caused by excess fluoride in osteoblasts

目的：观察人成骨细胞在过量氟作用下未折叠蛋白反应（UPR）信号通路的差异基因表达，探索在氟中毒条件下成骨细胞内质网应激的作用。方法体外培养人成骨细胞染氟模型，用不同浓度的氟干预24 h后M T S法检测细胞存活率和流式细胞仪检测细胞凋亡百分率，用UPR信号通路PCR Array芯片检测通路中相关基因表达的情况，并用蛋白免疫印迹法（Western blot）检测蛋白表达。结果在氟化钠浓度为0、5、10、20、40、80 mg/L 时，细胞存活率分别为（100．6785±2．8303）％、（105．3934±2．5384）％、（106．1257±2．0483）％、（77．9773±2．5443）％（与对照组比较 P＜0．05）、（30．2377±0．6327）％（与对照组比较 P＜0．05）。流式细胞仪检测，凋亡率分别为5mg/L组4．8％，10mg/L组13．8％，20mg/L组37．0％，40mg/L组58．9％，80 mg/L组63．2％（P＜0．05）。PCR芯片检测发现1个基因表达下调，14个基因表达上调。Western blot结果显示， BIP、ATF4、CHOP、IRE1均呈现出不同程度的随氟剂量增加蛋白表达逐渐上调。XBP1在NaF 5～20 mg/L表达逐渐增强，在40与80 mg/L时表达减弱。结论氟化钠可以通过PERK和IRE1途径引起成骨细胞内质网应激，并且可以引起成骨细胞凋亡。

Objective To observe gene different expression of unfolded protein response signaling pathway in human osteoblasts under the excessive fluoride ,and explore the role of endoplasmic reticulum stress in fluorosis .Methods Human osteoblasts were cultured with fluoride ,intervening for 24 h .Cell viability and apoptosis were inspected by MTS assay and flow cytometer respective‐ly .The UPR signaling pathway was examined by real time PCR array ,and protein expressions were detected by Western blot .Re‐sults T he cell survival rates w ere （100 .678 5 ± 2 .830 3 ）% ,（105 .393 4 ± 2 .538 4 ）% ,（106 .125 7 ± 2 .048 3 ）% ,（77 .977 3 ± 2 .544 3）% （P〈0 .05） ,（30 .237 7 ± 0 .632 73）% （P〈0 .05） treated with sodium fluoride at the concentration 0 ,5 ,10 ,20 ,40 ,80 mg/L respectively .Apoptosis rate inspected by flow cytometer was 4 .8% in 5 mg/L group ,13 .8% in 10 mg/L group ,37 .0% in 20 mg/L group ,58 .9% in 40 mg/L group ,63 .2% in 80 mg/L group （P〈0 .05） .Only 1 gene was down regulated and 14 genes were up regulated .Western blot analysis showed BIP ,ATF4 ,CHOP and IRE1 both showed their protein expression gradually up regula‐ted with fluorine dose .XBP1 expression gradually increased in NaF 5-20 mg/L ,and its expression decreased at 40 and 80 mg/L . Conclusion Sodium fluoride can cause osteoblasts endoplasmic reticulum stress pathway through PTEN and IRE1 pathway ,and at high concentrations can cause apoptosis of osteoblast .