二氢杨梅素通过TFEB-自噬途径抑制地塞米松诱导的成骨细胞凋亡  

Dihydromyricetin inhibits apoptosis induced by dexamethasone through TFEB autophagy pathway in osteoblast cells line MC3T3-E1 cells

作　　者：周湘华[1] 周寿红 赵其辉[1] ZHOU Xiang-hua;ZHOU Shou-hong;ZHAO Qi-hui(Dept of Pharmacology,Hunan University of Environment and Biology,Hengyang,Hunan 421001,China;Guangxi Key Lab of Brain and Cognitive Neuroscience;Dept of Physiology,Basic Medical College,Guilin Medical University,Guilin,Guangxi 541104,China)

机构地区：[1]湖南环境生物职业技术学院药理教研室,湖南衡阳421001 [2]广西脑与认知神经科学重点实验室 [3]桂林医学院基础医学院生理学教研室,广西桂林541104

出　　处：《中国药理学通报》2020年第8期1111-1117,共7页Chinese Pharmacological Bulletin

基　　金：湖南省自然科学基金资助项目(No 2016JJ2110);广西脑与认知神经科学重点实验室开放课题(No GKLBCN-20190105-02)。

摘　　要：目的观察二氢杨梅素(dihydromyricetin,DMY)对地塞米松(dexamethasone,DEX)诱导成骨细胞系MC3T3-E1细胞凋亡的影响并探寻其机制。方法用10、20和40μmol·L^-1 DMY处理MC3T3-E1细胞0.5 h,再加入10μmol·L^-1 DEX继续共同培养12 h。检测细胞增殖和凋亡水平及细胞超微结构,Western blot检测自噬相关基因和TFEB表达。结果与DEX组比较,DEX+DMY(20和40μmol·L^-1)组细胞的凋亡率明显降低,差异有统计学意义(P<0.05)。与DEX组比较,DEX+DMY(20μmol·L^-1)组细胞中自噬体的数量、自噬体占胞质面积百分率、Beclin-1和LC3-Ⅱ的蛋白表达及LC3-Ⅱ/LC3-Ⅰ比值均明显减少,p62蛋白表达明显上调,差异有统计学意义(均P<0.05)。雷帕霉素部分取消了DMY的效应。与DEX组比较,DEX+DMY(20μmol·L^-1)组细胞中TFEB在细胞核中和总蛋白表达及两者比值均明显降低,差异有统计学意义(均P<0.05)。结论DMY抑制了DEX诱导的成骨细胞的凋亡,其机制可能与DMY下调TFEB表达,抑制其核转位而抑制细胞自噬有关。Aim To observe the effect of dihydromyricetin(DMY)on the apoptosis of mouse osteoblasts MC3T3-E1 induced by dexamethasone(DEX)and explore its possible mechanism.Methods MC3T3-E1 cells were treated with 10,20 and 40μmol·L^-1 DMY for 0.5 h,and then 10μmol·L^-1 dexamethasone was added to co-culture for 12 h.The level of cell proliferation and apoptosis was analyzed.The ultrastructure of cells was observed.The expressions of autophagy related genes and TFEB were detected by Western blot.Results Compared with DEX group,the rate of apoptosis significantly decreased in DEX+DMY(20 and 40μmol·L^-1)group,the number of autophagy in the cytoplasm of cells obviously decreased,the percentage of autophagic vacuole area in the total cytoplasm area significantly decreased,the expressions of Beclin 1 andLC3-Ⅱand the ratio of LC3-Ⅱ/LC3-Ⅰsignificantly decreased,and the expression of p62 markedly increased(all P<0.05).Rapamycin,an autophagy inducer,partially cancelled the role of DMY which inhibited the apoptosis of MC3T3-E1 cells induced by DEX.Compared with DEX group,the total protein expression of TFEB and TFEB expresion in cell nucleus and the ratio of TFEB expresion in cell nucleus to TFEB total protein expression in cell significantly decreased in DEX+DMY(20μmol·L^-1)group(all P<0.05).Conclusions DMY inhibits the apoptosis of osteoblasts induced by DEX,and the mechanism may be related to the down-regulation of TFEB expression,the inhibition of TFEB nuclear translocation and the inhibition of autophagy induced by DMY.

关 键 词：二氢杨梅素 成骨细胞 地塞米松 凋亡 转录因子EB 自噬 

分 类 号：R-332[医药卫生] R284.1