LPS诱导MC3T3-E1成骨细胞增殖并增加NF-κB p65蛋白的表达

目的： 研究LPS-NF-κB信号通路在骨形成过程中的作用。方法: MC3T3-E1成骨细胞常规培养,待细胞融合率为80%时,分别加入100 μg/L和500 μg/L LPS处理6 h。流式细胞仪检测细胞周期,计算细胞DNA相对增殖指数;RT-PCR法检测LPS处理成骨细胞后NF-κB mRNA的表达;蛋白质印迹法（Western blotting）检测LPS处理成骨细胞后NF-κB p65蛋白的表达;细胞免疫荧光法检测LPS处理成骨细胞后NF-κB p65的核易位情况;电泳迁移率变动分析（EMSA）LPS处理MC3T3-E1细胞后NF-κB活力的变化情况。结果: 100 μg/L和500 μg/L LPS可诱导MC3T3-E1成骨细胞增殖;LPS处理成骨细胞后NF-κB mRNA的表达与正常组比较无显著变化（P>0.05）,而NF-κB p65蛋白的表达明显高于对照组（P<0.01）;LPS处理成骨细胞后免疫荧光法可明显观察到NF-κB p65从细胞质转移入细胞核,且EMSA结果显示LPS处理组细胞核内NF-κB结合活性增加。结论: 低浓度的LPS可促使成骨细胞增殖,此过程中并不影响NF-κB p65的基因表达水平,但能增加NF-κB p65蛋白的表达并提高细胞核内NF-κB的结合活性。     

长链非编码RNA H19抑制地塞米松致成骨细胞凋亡的作用

背景：激素性股骨头坏死的发病机制尚不清楚,成骨细胞凋亡与其关系密切。目的：探讨长链非编码RNA H19(long Non-Coding RNA H19,lncRNA H19)在地塞米松促进成骨细胞凋亡中的作用。方法：培养小鼠成骨细胞MC3T3-E1,分为对照组(不处理)和地塞米松组(1μmol/L地塞米松处理24 h),采用Western blot检测各组细胞Bax、Bcl-2和细胞外调节蛋白激酶(p-ERK1/2/ERK1/2)蛋白的表达,流式细胞术和细胞活力染色检测细胞凋亡情况,qRT-PCR检测lncRNAH19的表达。转染lncRNA H19阴性对照(ad-NC)和lncRNA H19过表达质粒(ad-lncRNA H19)并给予地塞米松干预24 h后,采用细胞活力染色、Western blot和流式细胞术检测MC3T3-E1细胞凋亡情况;使用MAPK-ERK通路抑制剂PD98059处理MC3T3-E1细胞24 h,Western blot检测各组细胞Bax和Bcl-2蛋白的表达。结果与结论：(1)与对照组相比,地塞米松组MC3T3-E1细胞凋亡率升高,lncRNA H19相对...     

不同浓度骨碎补总黄酮复合可注射骨修复材料对MC3T3-E1成骨细胞作用的实验研究

目的本实验旨在观察中药骨碎补提取物骨碎补总黄酮(AFDR)复合海藻酸基可注射骨修复材料对成骨细胞MC3T3-E1体外培养的影响。方法将成骨细胞株MC3T3-E1随机分为空白对照组、单纯使用海藻酸基可注射骨修复材料组、AFDR0.04mg/L、0.16mg/L、0.64mg/L、1.28mg/L、5.12mg/L 7组,体外复合海藻酸基可注射骨修复材料,以24h和48h为观察时间点,倒置显微镜观察MC3T3-E1细胞形态,台盼蓝拒染法检测MC3T3-E1存活率,MTT法观察细胞增殖效应,碱性磷酸酶(ALP)活性和骨钙素定量检测分别观察不同浓度骨碎补总黄酮促进MC3T3-E1分化作用,采用Von kossa钙化染色法观察其促MC3T3-E1细胞钙化作用。结果①倒置显微镜下观察复合海藻酸基可注射骨修复材料的MC3T3-E1细胞形态,细胞形态呈三角形、多边形、长梭形等,呈集落样生长,无接触抑制,有伪足伸出,胞液透亮,核圆形。AFDR各组不同程度促进成骨细胞的增殖、分化:7组能不同程度的促进成骨细胞的增殖、分化,与空白对照组比较,以0.16 mg/L和0.64mg/L剂量组的成骨细胞增殖数量最多,1.28mg/L,5.12mg/L的AFDR对细胞增殖作用不明显;②MC3T3-E1平均存活率≥90%;③骨碎补总黄酮(AFDR)0.16 mg/L和0.64mg/L剂量组在培养24小时和48小时,其OD值与空白对照组及组间均有显著性差异,可促进MC3T3-E1细胞增殖(P0.05和P0.01);④AFDR 0.16 mg/L和0.64mg/L剂量组能使MC3T3-E1的ALP活性升高(P0.05);⑤AFDR 0.64mg/L剂量组能促进MC3T3-E1骨钙素合成(P0.05);⑥AFDR 0.16 mg/L和0.64mg/L剂量组均可促进细胞钙化(P0.05)。结论 AFDR可显著促进在海藻酸基可注射骨修复材料上MC3T3-E1的增殖、分化和钙化,其作用具有时间依赖和剂量依赖关系。     

高糖通过提高ROS水平和钙超载诱导小鼠MC3T3-E1成骨细胞凋亡

目的: 探讨钙离子(Ca²⁺)超载在高糖诱导成骨细胞株MC3T3-E1凋亡中的作用以及活性氧簇(reactive oxygen species, ROS)的影响。方法: 培养小鼠颅骨源性成骨细胞株MC3T3-E1,给予高浓度D-葡萄糖诱导细胞凋亡。采用MTT法检测不同浓度D-葡萄糖处理24和48 h后MC3T3-E1细胞的增殖情况; D-葡萄糖(35 mmol/L)处理24 h后,Annexin V-FITC/PI检测细胞凋亡;Fura-2/AM荧光探针检测细胞内Ca²⁺浓度; DCFH-DA荧光探针检测ROS的生成。结果: MC3T3-E1高糖处理后,细胞增殖明显抑制呈剂量效应关系,早期凋亡率和总死亡率分别增加至(24.16±3.53)%和(63.74±4.32)%。高糖处理后细胞内ROS水平明显增加,抗氧化剂N-乙酰半胱氨酸可以在降低ROS水平的同时抑制高糖所引起的成骨细胞凋亡。细胞内游离Ca²⁺水平也明显增加,并且通过膜通透性Ca²⁺螯合剂BAPTA-AM处理后,细胞内Ca²⁺浓度明显降低,同时成骨细胞凋亡率也明显降低。加入镧离子(La³⁺)离子抑制储量操纵性钙通道(store-operated Ca²⁺ channels,SOCC)可以降低细胞内Ca²⁺浓度,减低高糖所引起的成骨细胞凋亡。在高糖诱导成骨细胞凋亡中,细胞内ROS和Ca²⁺的增加呈相互促进的关系。结论: 高糖可以通过增加细胞内ROS水平,引起钙离子通过SOCC通道释放,造成细胞内Ca²⁺超载,从而诱导成骨细胞凋亡。     

Tmed2促进体外小鼠前成骨细胞MC3T3-E1增殖

 摘要：目的 研究Tmed2基因对小鼠前成骨细胞增殖的影响。 方法 1.分别在小鼠MC3T3-E1细胞中过表达和抑制Tmed2,检测细胞增殖情况。2. 用雌激素处理细胞后,检测细胞的增殖及Tmed2基因的表达量。荧光实时定量PCR检测mRNA水平,MTS法检测细胞活力和增殖,流式细胞术检测细胞周期,Western blot法检测蛋白水平。结果 过表达Tmed2使MC3T3-E1细胞的增殖速度加快,细胞周期中S期细胞比例明显增加,且Cyclin A 的表达升高。而抑制Tmed2基因表达使MC3T3-E1细胞的增殖速度减慢。雌激素处理使细胞增殖速度加快的同时,Tmed2基因的表达显著增高。结论 Tmed2通过上调Cyclin A 的表达,使S期细胞比例增加,加快小鼠前成骨细胞MC3T3-E1的增殖。此外,Tmed2的表达受雌激素的调控,可能参与雌激素促进MC3T3-E1细胞增殖的作用。     

高糖对成骨细胞MC3T3-E1凋亡和氧化应激的影响

目的评价高糖环境对成骨细胞MC3T3-E1凋亡和氧化应激的影响,为临床治疗糖尿病骨质疏松症提供实验基础。方法在细胞培养瓶中加入不同浓度高糖溶液(0、20、40、80 mmol/L)培养成骨细胞株MC3T3-E1,24 h后分别采用CCK-8测定其细胞存活率、细胞凋亡率,线粒体膜电位试剂盒测定其去极化程度,半胱天冬酶-3(Caspase-3)试剂盒检测其活性,DCFH-DA荧光探针检测ROS的生成。在80 mmol/L高糖环境暴露,MC3T3-E1细胞在抗氧化剂NAC作用下,采用上述方法测其线粒体膜电位和Caspase-3含量。结果与对照组相比,成骨细胞MC3T3-E1在高糖暴露下的存活率和线粒体膜电位下降,细胞凋亡率、细胞活性氧水平和Caspase-3活性增强,且都存在剂量依赖性;抗氧化剂NAC抑制高糖引起MC3T3-E1细胞线粒体膜电位降低和Caspase-3增高。结论高糖环境下,NAC通过抑制高糖引起的氧化应激,降低细胞凋亡率,保护成骨细胞MC3T3-E1。     

铅暴露对成骨细胞MC3T3-E1细胞线粒体的影响

目的评价铅暴露对成骨细胞MC3T3-E1线粒体的影响。方法在MC3T3-E1细胞培养瓶中加入不同浓度醋酸铅[Pb(Ac)2]溶液(0、1、10、100μmol/L)培养24 h后,分别测定其线粒体膜电位去极化程度与ATP合成量、胞浆与线粒体内细胞色素c含量以及Caspase-3活性,并利用透射电镜观察细胞线粒体形态变化。结果铅暴露可致成骨细胞MC3T3-E1线粒体膜电位降低,ATP合成减少,细胞内细胞色素c从线粒体到胞浆的释放增加,Caspase-3活性增强,并且呈明显剂量依赖关系。此外,电镜观察可见100μmol/L醋酸铅暴露组细胞线粒体明显肿胀。结论铅暴露可引起成骨细胞MC3T3-E1线粒体功能与结构损伤,从而导致细胞凋亡。     

Asxl1在炎性微环境中对成骨细胞增殖分化的作用

背景:研究表明Asxl1的缺失可导致骨质发育不全、骨质缺损类疾病的发生,但目前在根尖周炎环境下该因子与骨破坏之间的关系暂无相关报道。目的:探讨炎性微环境下Asxl1对成骨细胞增殖分化的影响。方法:实验选用脂多糖刺激MC3T3-E1细胞建立体外炎性微环境,通过CCK-8实验筛取脂多糖最佳质量浓度和最佳作用时间,然后用20 mg/L脂多糖刺激MC3T3-E1细胞24 h,免疫荧光检测Asxl1的蛋白表达水平,Real Time-PCR检测Asxl1 mRNA的表达水平。为进一步验证Asxl1基因在炎性微环境中影响成骨细胞的增殖与分化,脂多糖刺激形成炎性微环境后转染Asxl1-SiRNA 24 h,采用CCK-8检测细胞增殖活性,RealTime-PCR检测Asxl1及成骨相关基因ALP和RUNX2 mRNA的表达水平。结果与结论:①脂多糖刺激MC3T3-E1细胞后,Asxl1蛋白和mRNA表达水平呈降低趋势;②脂多糖刺激MC3T3-E1细胞后,转染Asxl1-SiRNA 24 h,细胞增殖活性下降趋势明显,Asxl1基因及成骨相关基因ALP和RUNX2 mRNA的表达水平明显降低;③结果提示,Asxl1可能通过参与炎性反应过程,影响成骨细胞的增殖与分化,进而参与骨破坏进程。     

ROS/PARP-1/AIF信号通路在糖皮质激素诱导的MC3T3-E1细胞凋亡过程中的作用研究

目的通过用地塞米松诱导小鼠胚胎成骨细胞前体细胞(MC3T3-E1)的凋亡,建立激素性股骨头坏死的细胞模型,探讨抗氧化剂(N-乙酰-L-半胱氨酸,NAC)和钙蛋白酶的抑制剂(PD151746)对MC3T3-E1细胞抑制凋亡的作用和可能机制的研究。方法 CCK-8检测NAC和PD151746不同药物浓度对MC3T3-E1细胞增殖的影响,选择合适的药物浓度。细胞分组:正常组(10%FBS),激素组(地塞米松1×10~(-6) mol/L),NAC组(NAC1 mmol/L+地塞米松1×10~(-6) mol/L)和PD151746组(简称PD组,PD 10 mol/L+地塞米松1×10-6 mol/L),流式细胞仪检测细胞凋亡率和ROS含量,激光扫描共聚焦显微镜检测各组ROS荧光强度和钙离子荧光强度,Western blot测定细胞蛋白AIF、PARP-1和Cyt-c的表达水平。结果 CCK-8结果显示,NAC和PD151746的实验浓度分别取1 mmol/L和10 mol/L。流式细胞仪检测凋亡率结果显示,激素组、NAC组和PD组的凋亡率与正常组比较,差异有统计学意义(0.05),激素组与NAC组、PD组比较差异有统计学意义(0.05)。流式细胞仪和激光扫描共聚焦显微镜检测各组ROS含量,结果显示激素组荧光强度最高,与NAC组和PD组比较明显增高(0.05),其他三组与正常组比较差异也具有统计学意义(0.05)。激光扫描共聚焦显微镜检测钙离子荧光强度,与NAC组和PD组比较明显增高(0.05),其他三组与正常组比较差异也具有统计学意义(0.05)。Western blot检测各组AIF、PARP-1和Cyt-c的表达水平,激素组、NAC组和PD组的凋亡率与正常组比较,差异有统计学意义(0.05),激素组与NAC组、PD组比较差异有统计学意义(0.05)。结论 NAC能抑制地塞米松诱导的ROS产生,PD151746能有效抑制钙蛋白酶的活性,抑制PAPR-1/AIF的释放,抑制成骨细胞凋亡,ROS/PARP-1/AIF通路参与了地塞米松诱导MC3T3-E1细胞的凋亡过程。     

Caveolin-1介导流体剪切应力调控MC3T3-E1成骨细胞增殖和凋亡

背景：流体剪切应力在成骨细胞增殖和凋亡中起着重要作用。然而,Caveolin-1(Cav-1)是否参与成骨细胞中流体剪切应力诱导的增殖与凋亡过程尚不清楚。目的：探讨Cav-1在流体剪切应力调控成骨细胞增殖和凋亡中的作用。方法：选择生长状态良好的MC3T3-E1成骨细胞,加载不同时间(0,30,60,90 min)且强度为1.2 Pa的流体剪切应力,观察Cav-1蛋白的表达,筛选出时间为60 min的条件进行实验。将MC3T3-E1细胞分为：对照组、流体剪切应力组、流体剪切应力+pcDNA 3.1组(对照)、流体剪切应力+pcDNA Cav-1组(过表达质粒),分别采用流体剪切应力和过表达Cav-1等方式干预,通过q RT-PCR和Western blot检测MC3T3-E1细胞内增殖以及凋亡相关分子的表达量;通过CCK-8与Ed U实验检测MC3T3-E1细胞增殖活性;采用Hoechst 33258染色以及流式细胞术检测MC3T3-E1细胞凋亡情况。结果与结论：加载流体剪切应力后MC3T3-E1细胞中Cav-1的表达显著下调,且加载60 min表达水平最低。过表达Cav-1减弱了流体剪...     

左归丸含药血清通过ERK/TGF-β/Smads信号级联调控MC3T3-E1细胞增殖与分化

目的:研究细胞外信号调节激酶(ERK)/转化生长因子β(TGF-β)/Sma和Mad相关蛋白(Smads)信号级联在左归丸含药血清干预成骨前体细胞系MC3T3-E1细胞增殖与分化中的作用。方法:以倍美力为阳性对照药,对Sprague-Dawley(SD)雌性大鼠灌服高、中、低剂量的左归丸混悬液,7 d后腹主动脉取血分离含药血清。采用噻唑蓝(MTT)法检测左归丸含药血清对MC3T3-E1细胞的增殖作用,采用改良钙钴染色法检测碱性磷酸酶(ALP)表达,采用茜素红染色法检测钙化结节,采用Western blotting法检测核结合因子α1(Cbfα1)和Ⅰ型胶原(ColⅠ)蛋白表达,采用real-time RT-PCR法检测TGF-β₁、Smad4和Smad2 mRNA表达。结果:左归丸含药血清对MC3T3-E1细胞的促增殖作用呈剂量和时间相关性,其中以低剂量且体积分数为15%作用48 h后对MC3T3-E1的促增殖作用最大;左归丸含药血清能促进MC3T3-E1细胞ALP表达,增强细胞基质钙化,提高Cbfα1和ColⅠ蛋白分泌,上调TGF-β₁、Smad4和Smad2 mRNA表达;加入ERK1/2信号通路特异性阻滞剂PD98059后,MC3T3-E1细胞增殖降低,ALP表达下降,细胞基质钙化减弱,Cbfα1和ColⅠ蛋白分泌降低,Smad4和Smad2 mRNA表达下调,TGF-β₁ mRNA表达进一步上调。结论:左归丸可能通过干预ERK/TGF-β/Smads信号级联而调控成骨细胞的增殖和分化,这可能是其防治骨质疏松症的机制之一。     

牵张应力介导细胞成骨分化及相关基因的表达

背景：ERK1/2信号通路和核因子κB信号通路是否参与了牵张应力作用下MC3T3-E1细胞成骨分化及相关基因表达的调控,尚不清楚。 目的：观察机械牵张应力对作用下ERK1/2和核因子κB通路对成骨细胞碱性磷酸酶、Ⅰ型胶原、骨钙蛋白、白细胞介素6表达的影响,探讨ERK1/2与核因子κB信号通路对成骨细胞分化的调控作用。 方法：体外培养的MC3T3-E1细胞,以ERK1/2通路特异性抑制剂PD098059及核因子κB通路抑制剂PDTC分别处理30 min后加载12%的拉伸应变率24 h,以正常细胞及单纯加载12%牵张应力24 h为对照。采用ELISA及Real-time PCR方法检测细胞加载前后碱性磷酸酶活性、Ⅰ型胶原、骨钙蛋白及白细胞介素6 mRNA的表达。 结果与结论：在12%牵张应力作用下,MC3T3-E1细胞碱性磷酸酶、Ⅰ型胶原、白细胞介素6的表达受ERK1/2信号通路的调控,而骨钙蛋白基因表达的变化不受ERK1/2通路的影响。核因子κB信号通路抑制剂PDTC可显著抑制机械牵应张力作用下MC3T3-E1细胞碱性磷酸酶活性的降低,同时抑制白细胞介素6基因的表达,而Ⅰ型胶原、骨钙蛋白基因表达的变化不受核因子κB信号通路的影响。结果表明牵张应力可以通过ERK1/2和核因子κB通路影响MC3T3-E1细胞的成骨分化及相关基因表达。 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程全文链接：     

人牙周膜干细胞来源外泌体干预成骨细胞MC3T3-E1的增殖和分化

背景:人牙周膜干细胞具有较强的成骨分化能力,人牙周膜干细胞来源外泌体作为牙周膜干细胞分泌的主要成分,对成骨细胞MC3T3-E1增殖和成骨分化的影响尚不明确。目的:探讨人牙周膜干细胞来源外泌体对MC3T3-E1细胞增殖和分化的影响。方法:采用酶消化法分离及培养人牙周膜干细胞,超速离心法提取人牙周膜干细胞来源外泌体,通过透射电镜、粒径分析及Western blot方法对人牙周膜干细胞来源外泌体进行鉴定;CCK8法检测不同质量浓度人牙周膜干细胞来源外泌体对MC3T3-E1细胞增殖的影响,茜素红染色观察100 mg/L人牙周膜干细胞来源外泌体对MC3T3-E1细胞成骨矿化的影响,Western blot检测100 mg/L人牙周膜干细胞来源外泌体干预前后MC3T3-E1细胞内MEK和ERK的磷酸化水平。结果与结论:①透射电镜观察可见外泌体为脂质双分子层形成的囊泡结构,粒径检测显示外泌体直径分布在50-120 nm,集中在79.86 nm,Western blot检测结果显示提取的外泌体中含有CD81,CD63,TSG101的表达;②与对照组相比,人牙周膜干细胞来源外泌体对MC3T3-E1细胞的增殖具有促进作用,且作用呈剂量依赖性;③与对照组相比,人牙周膜干细胞来源外泌体组MC3T3-E1细胞能够形成更多的钙结节;与对照组相比,人牙周膜干细胞来源外泌体组MC3T3-E1细胞内p-MEK及p-ERK蛋白表达量升高;④结果表明,人牙周膜干细胞来源外泌体可以显著促进MC3T3-E1增殖和成骨分化,推测可能与其激活MEK/ERK信号通路有关。     

Fluid shear stress promotes osteoblast proliferation via the Gαq–ERK5 signaling pathway

Fluid shear stress (FSS) is a ubiquitous mechanical stimulus that potently promotes osteoblast proliferation. Previously, we reported that extracellular signal–regulated kinase 5 (ERK5) is essential for FSS-induced osteoblast proliferation. However, the precise mechanism by which FSS promotes osteoblast proliferation via ERK5 activation is poorly understood. The aim of this study was to determine the critical role of Gαq in FSS-induced ERK5 phosphorylation and osteoblast proliferation, as well as the downstream targets of the Gαq–ERK5 pathway. MC3T3-E1 cells were transfected with 50 nM Gαq siRNA, treated with 5 mM XMD8-92 (a highly selective inhibitor of ERK5 activity), and/or exposed to FSS (12 dyn/cm²). Cell proliferation was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The protein expression levels of Gαq, P-ERK5, ERK5, Cyclin B1, and CDK1 were analyzed by Western blot. Physiological FSS exposure for 60 min remarkably promoted MC3T3-E1 cell proliferation, however, this effect was suppressed by siRNA-mediated Gαq knockdown or inhibition of ERK5 activity by XMD8-92 treatment, suggesting that Gαq and ERK5 might modulate FSS-increased osteoblast proliferation. Furthermore, ERK5 phosphorylation was dramatically inhibited by Gαq siRNA. In addition, our study further revealed that FSS treatment of MC3T3-E1 cells for 60 min markedly upregulated the protein expression levels of Cyclin B1 and CDK1, and this increased expression was predominantly blocked by Gαq siRNA or XMD8-92 treatment. We propose that FSS acts on the Gαq–ERK5 signaling pathway to upregulate Cyclin B1 and CDK1 expression, thereby resulting in MC3T3-E1 cell proliferation. Thus, the Gαq–ERK5 signaling pathway may provide useful information regarding the treatment of bone metabolic disease.     

Effects of different oxygen concentrations on the proliferation,survival, migration,and osteogenic differentiation of MC3T3-E1 cells

In physiological and pathological environments, the concentration of oxygen around osteoblasts varies widely. No studies have systematically evaluated the effects of different oxygen concentrations on the proliferation, survival, migration, and osteogenic differentiation of osteoblasts. In this study, we cultured the osteoblast precursor cell line MC3T3-E1 in small individual chambers with oxygen concentrations of 1%, 3%, 6%, 9%, and 21%. Cell proliferation was evaluated by the proliferation index test and EdU staining. To test cell survival, a live/dead assay was performed. A tablet scratch assay was performed to detect the migratory ability of the cells. Bone nodule formation experiments and immunofluorescence and Western blotting analyses of osteogenic-related proteins were performed to assess the osteogenic differentiation of the cells. We found that the proliferation and osteogenic differentiation ability of MC3T3-E1 cells in different oxygen concentrations were both approximately bell-shaped curves and that the optimal oxygen concentrations were approximately 6% and 9%, respectively. The live/dead assay showed that the survival of MC3T3-E1 cells in different oxygen concentrations was affected by the amount of serum. The tablet scratch experiment showed that there was greater cell migration with oxygen concentrations of 1%, 3%, and 21% than with oxygen concentrations of 6% and 9%. Our results have significant reference value for the intervention of the pathological processes involving osteoblasts, such as fracture, osteoporosis, and some vascular diseases. These results also have an important guiding role for the new scientific idea that osteoblasts can function as treatment cells to repair bone defects.     

miR-199a-3p 通过靶向 CABLES-1 调控流体剪切力介导的成骨细胞增殖

目的 探讨miR-199a-3p在流体剪切力(fluid shear stress, FSS)诱导成骨细胞增殖中的作用及其可能的分子机制。方法 对成骨细胞MC3T3-E1加载1.2 Pa FSS,时间分别为0、15、30、45、60、75、90 min。使用miR-199a-3p模拟物或miR-199a-3p抑制物转染MC3T3-E1细胞。使用将过表达的miR-199a-3p以及其阴性对照分别转染MC3T3-E1细胞,并以1.2 Pa FSS处理45 min。将pcDNA NC、pcDNA-CABLES-1、si RNA NC、si RNA CABLES-1转染至MC3T3-E1细胞中。分别共转染pc DNA-CABLES-1与miR-199a-3p mimic以及si RNA-CABLES-1与miR-199a-3p inhibitor。CCK-8实验检测细胞活性;RT-qPCR检测CABLES-1、 miR-199a-3p、CDK 6、Cyclin D1、PCNA表达水平;荧光素酶报告实验检测CABLES-1和miR-199a-3p的靶向关系。免疫荧光检测CABLES-1蛋白表达。...     

Effect of borate glass composition on its conversion to hydroxyapatite and on the proliferation of MC3T3-E1 cells

Glasses containing varying amounts of B(2)O(3) were prepared by partially or fully replacing the SiO(2) in silicate 45S5 bioactive glass with B(2)O(3). The effects of the B(2)O(3) content of the glass on its conversion to hydroxyapatite (HA) and on the proliferation of MC3T3-E1 cells were investigated in vitro. Conversion of the glasses to HA in dilute (20 mM) K(2)HPO(4) solution was monitored using weight loss and pH measurements. Proliferation of MC3T3-E1 cells was determined qualitatively by assay of cell density at the glass interface after incubation for 1 day and 3 days, and quantitatively by fluorescent measurements of total DNA in cultures incubated for 4 days. Higher B(2)O(3) content of the glass increased the conversion rate to HA, but also resulted in a greater inhibition of cell proliferation under static culture conditions. For a given mass of glass in the culture medium, the inhibition of cell proliferation was alleviated by using glasses with lower B(2)O(3) content, by incubating the cell cultures under dynamic rather than static conditions, or by partially converting the glass to HA prior to cell culture.