自噬在氟牙症大鼠成釉细胞中的保护作用  

Protection effect of autophagy on the ameloblast apoptosis in rats with chronic fluorosis

作　　者：翁清清 易芳羽 郁莹 葛苏钰 张颖[1,2] WENG Qingqing;YI Fangyu;YU Ying;GE Suyu;ZHANG Ying(Department of Preventive Dentistry,Shanghai Stomatological Hospital,Fudan University,Shanghai 200001,China)

机构地区：[1]复旦大学附属口腔医院,上海市口腔病防治院口腔预防处,上海200001 [2]复旦大学附属口腔医院口腔生物医学工程实验室,上海200001

出　　处：《口腔医学》2020年第11期982-986,共5页Stomatology

基　　金：国家自然科学基金(81773369);上海市自然科学基金(16ZR1430600)。

摘　　要：目的研究不同程度氟牙症大鼠模型切牙成釉细胞的自噬及凋亡水平,探讨自噬在氟牙症大鼠成釉细胞凋亡中的作用。方法48只4周龄Wistar大鼠随机分为6组,通过饮水加75 mg/L和150 mg/L氟离子和腹腔注射10 mg/kg 3⁃甲基腺嘌呤(3⁃methyladenine,3⁃MA)的方法建立氟牙症大鼠模型及自噬抑制大鼠模型。观察成釉细胞形态改变和自噬相关蛋白Bec⁃lin1、自噬底物蛋白p62、微管相关蛋白轻链3(microtubule⁃associated protein light chain 3,LC3)及活化的含半胱氨酸的天冬氨酸蛋白水解酶3(Cleaved Caspase⁃3)蛋白表达水平,采用SPSS 22.0软件包对免疫组化定量结果进行统计学分析。结果随着饮水氟离子含量增加,切牙氟牙症表现明显,成釉细胞形态结构紊乱。免疫组化结果显示饮用150 mg/L含氟水的大鼠成釉细胞中Beclin1、LC3和Cleaved Caspase⁃3蛋白表达量增加,p62表达量下降,比饮用75 mg/L含氟水组大鼠改变更加明显。同时,在相同饮水条件下,3⁃MA抑制自噬后成釉细胞中Beclin1和LC3表达量下降,p62表达量升高,Cleaved Caspase⁃3蛋白水平明显增加。结论氟牙症大鼠成釉细胞中存在自噬,高浓度氟刺激对其诱导作用加强,并且自噬在一定程度上可以保护氟牙症大鼠成釉细胞免受凋亡。Objective To investigate the levels of autophagy and apoptosis of ameloblasts in rats with different degrees of fluorosis,and to explore the effect of autophagy on the ameloblast apoptosis in rats with chronic fluorosis.Methods Forty⁃eight 4⁃week⁃old Wist⁃ar rats were randomly divided into 6 groups to establish a fluorosis rat model by adding 75 mg/L or 150 mg/L fluoride to the drinking water,and an autophagy inhibition model treated with an intraperitoneal injection of 10 mg/kg 3⁃methyladenine(3⁃MA).The morphol⁃ogy and expression of Beclin1,p62,LC3,and Cleaved Caspase⁃3 in rat incisor ameloblasts were observed,and statistical analysis of quantitative results of immunohistochemistry was performed using SPSS 22.0 software package.Results With the increase of fluoride in drinking water,features of dental fluorosis became more obvious and disorders were found in morphology and structure of amelo⁃blasts.Results of immunohistochemistry showed that the expression of Beclin1 and LC3 increased while p62 expression decreased in rat ameloblasts drinking 150 mg/L fluoride,and the expression of Cleaved Caspase⁃3 increased.These changes were more obvious than rats drinking 75 mg/L fluoride⁃containing water.Meanwhile,under the same drinking condition,after administration 3⁃MA to inhibit auto⁃phagy,and they,in turn,decreased the expression of Beclin1 and LC3 and increased the p62 expression.The expression level of Cleaved Caspase⁃3 in ameloblast increased significantly.Conclusion There is autophagy in rat ameloblasts with chronic fluorosis,the induction of which is enhanced by the high concentration of fluoride and may play a protective role in reducing the level of apoptosis in ameloblasts during the fluorosis.

关 键 词：氟牙症 成釉细胞 自噬 凋亡 大鼠 

分 类 号：R780.2[医药卫生—口腔医学]