LncRNA FGD5-AS1靶向miR-103a-3p对IL-1β诱导的关节软骨细胞凋亡的机制研究

目的探讨LncRNA FGD5-AS1靶向miR-103a-3p对IL-1β诱导的关节软骨细胞损伤及细胞凋亡的影响与分子机制。方法体外培养大鼠关节软骨细胞,分为NC组、IL-1β组(IL-1β浓度为10 ng/m L)。采用qRT-PCR检测细胞中FGD5-AS1、miR-103a-3p的表达水平。分别将pc DNA-FGD5-AS1、miR-103a-3p mimics转染至软骨细胞,随后使用IL-1β处理48 h。采用ELISA检测IL-6、TNF-α、IL-8水平;流式细胞术检测细胞凋亡率;双荧光素酶报告实验验证FGD5-AS1与miR-103a-3p的靶向关系; Western blot检测Bax、Cyt C、Cleaved Caspase-3、p-NF-κB p65、p-IκBα蛋白表达量。结果与NC组相比,IL-1β组软骨细胞中FGD5-AS1的表达水平显著降低(P0.05),miR-103a-3p、Bax、Cyt C、Cleaved Caspase-3的表达水平显著升高(P0.05),IL-6、TNF-α、IL-8水平显著升高(P0.05),细胞凋亡率显著升高(P0.05); FGD5-AS1过表达后可明显降低IL-6、TNF-α、IL-8、p-NF-κB p65、p-IκBα水平(P0.05),降低细胞凋亡率(P0.05),抑制Bax、Cyt C、Cleaved Caspase-3表达(P0.05);双荧光素酶报告实验证实FGD5-AS1靶向结合miR-103a-3p并可负向调控miR-103a-3p的表达(P0.05); miR-103a-3p过表达可明显逆转FGD5-AS1过表达对细胞凋亡及炎症反应的抑制作用(P0.05)。结论 LncRNA FGD5-AS1可通过靶向负调控miR-103a-3p的表达从而抑制IL-1β诱导的关节软骨细胞炎症反应及细胞凋亡,其作用机制可能通过抑制NF-κB信号通路激活有关。     

成软骨相关miR-4287调控人软骨细胞聚蛋白多糖酶-1表达的研究

目的探讨成软骨相关miR-4287对人软骨细胞聚蛋白多糖酶-1(a disintegrin and metalloproteinase with thrombospondin motif 4,ADAMTS4)调控作用及其机制。方法取自愿捐赠的膝关节正常及骨关节炎软骨组织,采用实时荧光定量PCR检测miR-4287和ADAMTS4 mRNA表达量;然后分离培养软骨细胞,取第1代骨关节炎细胞,给予IL-1β处理,观察其对软骨细胞miR-4287和ADAMTS4 mRNA表达的影响;分别给予MAPK信号通路抑制剂SP600125以及NF-κB信号通路抑制剂SN50预处理后联合IL-1β刺激,观察IL-1β介导的信号通路对软骨细胞miR-4287和ADAMTS4 mRNA表达的影响;分别转染miR-4287模拟物及其阴性对照、miR-4287抑制物及其阴性对照,观察miR-4287调控软骨细胞ADAMTS4 mRNA及蛋白的表达。荧光素酶报告实验验证miR-4287与ADAMTS4 mRNA 3’非翻译区(untranslated region,UTR)的直接结合效应。结果与正常软骨组织比较,骨关节炎软骨组织miR-4287相对表达量下降,ADAMTS4 mRNA相对表达量上升,比较差异有统计学意义(P0.05)。IL-1β下调软骨细胞miR-4287表达、上调ADAMTS4 mRNA表达,与未经IL-1β处理的软骨细胞相比差异均有统计学意义(P0.05)。经IL-1β介导的信号通路抑制剂预处理后,软骨细胞miR-4287相对表达量上升,ADAMTS4 mRNA相对表达量降低,与未经信号通路抑制剂预处理细胞相比,差异均有统计学意义(P0.05)。转染miR-4287模拟物后,软骨细胞内ADAMTS4 mRNA及蛋白表达均降低(P0.05);而转染miR-4287抑制物后,软骨细胞内ADAMTS4 mRNA及蛋白表达均升高(P0.05)。无论结合位点为野生型或突变型,过表达miR-4287均不能改变报告载体的荧光素酶活性(P0.05)。结论成软骨相关miR-4287可能是一种与软骨退变相关的miRNA。miR-4287能调控人软骨细胞ADAMTS4表达,但不是通过靶向结合mRNA 3’UTR的方式发挥作用,其具体机制有待进一步研究。     

通络止痛凝胶制剂对KOA滑膜组织中p53/miR-502-5p/NF-κBp65的影响

目的:观察通络止痛凝胶制剂对膝骨关节炎(knee osteoarthritis,KOA)滑膜组织中p53、miR-502-5p、NF-κBp65的影响,探讨通络止痛凝胶制剂治疗KOA的作用机制。方法:选取8周龄Wistar大鼠36只,体重200～220 g,平均208 g,采用随机数字表法分为正常组、模型组、中药组,每组12只。采用改良Hulth法建立KOA模型,造模4周后,中药组给予通络止痛凝胶制剂外擦,3次/天,共2周;正常组和模型组正常饲养、不干预。治疗结束后,观察各组标本形态学变化;采用qPCR检测滑膜组织miR-502-5p的变化,再分别采用qPCR、Western Blot法检测滑膜组织p53、NF-κBp65、IL-1β、TNF-α、MMP-13的含量。结果:(1)标本形态学观察结果,模型组关节软骨透明度下降、表面不平整,滑膜肥厚增生并有大量炎性细胞浸润,关节液质地较黏稠;中药组关节软骨透亮度下降不明显,关节面较平整,滑膜轻度增生并有少量炎性细胞浸润,关节液质地较清晰。(2)与正常组比较,模型组、中药组滑膜组织miR-502-5p含量升高(P0.05),p53的mRNA及蛋白表达下降(P0.05),NF-κBp65、IL-1β、TNF-α、MMP-13的mRNA及蛋白表达升高(P0.05)。(3)与模型组比较,中药组滑膜组织miR-502-5p含量降低(P0.05),p53的mRNA及蛋白表达升高(P0.05),NF-κBp65、IL-1β、TNF-α、MMP-13的mRNA及蛋白表达降低(P0.05)。结论 :滑膜组织中p53、miR-502-5p、NFkBp65的表达与滑膜的增生及炎症反应密切相关,通络止痛凝胶制剂可能是通过调控滑膜组织中p53、miR-502-5p、NF-κBp65的表达,从而减轻KOA滑膜的增生及炎症反应。     

hsa_circ_0005105靶向miR-508-3p对关节炎软骨细胞的影响

目的 探讨hsa_circ_0005105对关节炎软骨细胞增殖、凋亡及炎症因子分泌的影响及机制。方法 实时荧光定量PCR（RT-qPCR）检测软骨细胞中hsa_circ_0005105和miR-508-3p的表达水平;将软骨细胞分为NC组、IL-1β组、IL-1β+si-NC组、IL-1β+si-hsa_circ_0005105组、IL-1β+miR-NC组、IL-1β+miR-508-3p组、IL-1β+si-hsa_circ_0005105+anti-miR-NC组、IL-1β+si-hsa_circ_0005105+anti-miR-508-3p组;蛋白质印迹法检测凋亡蛋白表达;流式细胞术检测凋亡;CCK-8与平板克隆形成能力检测细胞增殖能力;酶联免疫吸附法检测TNF-α、IL-6水平;双荧光素酶报告实验检测hsa_circ_0005105和miR-508-3p的靶向关系。结果 IL-1β诱导的软骨细胞中hsa_circ_0005105表达水平升高,miR-508-3p表达水平降低（P<0.05）。低表达hsa_circ_0005105或过表达miR-508-3p可降低IL-1β诱导的软骨细胞Bax、Cleaved-caspase-9、Cleaved-caspase-3相对表达水平、细胞凋亡率,升高Bcl-2蛋白水平、细胞活性,细胞克隆形成数增多,TNF-α和IL-6水平降低（P<0.05）。hsa_circ_0005105靶向调控miR-508-3p;低表达miR-508-3p可以逆转hsa_circ_0005105低表达对IL-1β诱导的软骨细胞损伤及炎症因子分泌的影响。结论 低表达hsa_circ_0005105通过靶向上调miR-508-3p抑制IL-1β诱导的软骨细胞凋亡及炎症因子分泌,促进细胞增殖。     

微小RNA-27b-3p与基质金属蛋白酶13在人软骨细胞的对应关系

目的探讨微小RNA-27b-3p(miR-27b-3p)与基质金属蛋白酶-13(MMP-13)在人软骨细胞表达及其靶向对应关系。 方法运用蛋白质印迹法(WB)与实时定量PCR技术(qRT-PCR)明确miR-27b-3p与MMP13在正常和骨关节炎(OA)人软骨细胞的表达。利用不同浓度的白介素(IL)1β干预原代人软骨细胞24 h,或利用不同时间点的IL-1β(10 ng/ml)干预原代人软骨细胞。利用原位杂交、转染及双荧光素酶报告技术确定miR-27b-3p与MMP13的靶向对应关系;结合运用核转录因子-κB(NF-κB)和丝裂原活化蛋白激酶(MAPK)信号通路抑制剂评估其作用机制。两组资料比较采用独立样本t检验,多组资料比较采用单因素方差分析,LSD法多重比较检验。 结果WB、qRT-PCR和原位杂交检测结果显示,与正常软骨相比,OA软骨中miR-27b-3p表达降低(t＝5.07,P<0.01),MMP13表达升高(t＝－6.31,P<0.01)。IL-1β干扰后的结果显示miR-27b-3p表达降低(F＝129.54,P<0.05),MMP-13表达升高(F＝394.50,P<0.05)。通过TargetScan数据库和荧光素酶报告基因检测结果分析,野生型-MMP13组荧光素酶活性降低(F＝55.27,P<0.001),突变型-MMP-13荧光素酶活性变化没有统计学意义(P＝0.654)。利用特异性MAPK信号抑制剂和NF-kB抑制剂干预IL-1β诱导软骨细胞模型结果提示,与对照组相比,抑制剂组的MMP13表达水平降低(F＝28.43,P<0.001),miR-27b-3p表达水平增高(F＝35.04,P<0.001)。 结论miR-27b-3p在OA软骨细胞呈现低表达,并负向调控MMP13的表达,其作用机制可能是通过NF-κB和MAPK信号通路,这结果提示这miR-27b-3p可能作为OA诊断与治疗的潜在靶点。     

miR-122-3p通过wnt/β catenin信号通道调控小鼠脂肪间充质干细胞成骨分化

[目的]探究miR-122-3p在小鼠脂肪间充质干细胞成骨分化中的调控机制。[方法]从6只雄性C57BL/6小鼠获取m ADSCs,成骨诱导培养基中培养,观察成骨情况。miR-122-3p、miR-NC、antimiR-122-3p和anti-NC基因慢病毒转染m ADSCs,q RT-PCR检测miR-122-3p表达以及成骨特异性基因Ocn及Alp的m RNA表达。Western blotting检测β-catenin的蛋白表达量。[结果]成骨诱导培养后,m ADSCs开始成骨分化,ALP染色和茜素红染色阳性。经转染后,过表达miR-122-3p会抑制m ADSCs成骨分化。反之,敲减miR-122-3p会促进m ADSCs成骨分化。Western Blotting检测表明,过表达miR-122-3p会激活Wnt/β-catenin信号通路。反之,敲减miR-122-3p会抑制Wnt/β-catenin信号通路。[结论] miR-122-3p通过调控Wnt/β-catenin信号通路,影响小鼠m ADSCs成骨分化。     

微小RNA-215-5p/锌指结构E-box同源结合框2促进白细胞介素-1β诱导软骨细胞凋亡在骨关节炎中的作用机制

目的探讨微小RNA(miR)-215-5p对白细胞介素(IL)-1β诱导的骨关节软骨细胞凋亡的影响及其机制。方法将骨关节炎软骨细胞ATDC5随机分为磷酸盐缓冲液(PBS)处理对照组和IL-1β处理模型组。为了分析miR-215-5p对IL-1β诱导细胞凋亡的影响, 进一步的将IL-1β组分为:模型组+miR对照组, 模型组+miR-215-5p抑制剂组。细胞转染后采用10 ng/ml IL-1β处理软骨细胞。采用流式细胞术检测细胞凋亡水平。采用实时定量反转录聚合酶链反应(RT-qPCR)检测miR-215-5p和锌指结构E-box同源结合框2(ZEB2)的表达水平。蛋白质印迹法(Western blot)检测ZEB2、p65、磷酸化p65、裂解的半胱氨酰天冬氨酸特异性蛋白酶-3(cleaved Caspase-3)蛋白水平。将野生型ZEB2的3’-非编码区(pmiR-ZEB2-WT)或者突变型ZEB2的3’-非编码区(pmiR-ZEB2-Mut)分别与miR-215-5p模拟物(miR-215-5p mimic)和对照物(miR-NC)共转染细胞, 双荧光素酶报告基因测定实验研究miR...     

LncRNA NUTM2A-AS1调控miR-183-5p/TGFα影响骨关节炎软骨细胞增殖、凋亡的研究

目的 探讨LncRNA NUTM2A-AS1对白细胞介素-1β（IL-1β）诱导的软骨细胞损伤的影响及分子机制。方法 将软骨细胞随机分为对照组、模型组（5 μg/L的IL-1β）、miR-183-5p+模型组、miR-NC+模型组、si-LncRNA NUTM2A-AS1+模型组、si-TGFα+模型组、si-NC+模型组、pcDNA-TGFα+si-LncRNA NUTM2A-AS1+模型组、pcDNA+si-LncRNA NUTM2A-AS1+模型组;运用实时荧光定量PCR（RT-qPCR）检测LncRNA NUTM2A-AS1、miR-183-5p和TGFα mRNA的表达水平;运用细胞计数试剂盒8（CCK-8）检测细胞活性;运用流式细胞术检测软骨细胞凋亡情况;通过酶联免疫吸附法（ELISA）检测TNF-α、IL-6水平;通过双荧光素酶报告实验检测NUTM2A-AS1、miR-183-5p、TGFα之间的靶向关系。结果 IL-1β诱导的软骨细胞中LncRNA NUTM2A-AS1和TGFα表达升高,miR-183-5p表达降低,软骨细胞活性降低,而凋亡率升高,TNF-α、IL-6水平升高。低表达LncRNA NUTM2A-AS1、低表达TGFα或过表达miR-183-5p后可促进细胞增殖及抑制细胞凋亡、炎症反应。结论 低表达LncRNA NUTM2A-AS1通过调控miR-183-5p/TGFα抑制IL-1β诱导的软骨细胞凋亡及炎症反应,促进细胞存活。     

麻黄碱调控AMPK/NF-κB信号通路改善大鼠膝骨关节炎的实验研究

目的 探讨麻黄碱(Ephedrine)调控腺苷酸活化蛋白激酶(AMPK)/核转录因子-κB(NF-κB)信号通路对大鼠膝骨关节炎(KOA)的影响。方法 建立KOA大鼠模型，将大鼠分为Sham组、KOA组、Ephedrine组(40.0 mg/kg)、Ephedrine(40.0 mg/kg)+Compound C组(0.2 mg/kg),药物分组干预后，分别检测大鼠膝关节宽度与疼痛阈值，番红O-固绿染色观察软骨组织病理变化并进行Mankin评分，ELISA法检测关节液TNF-α、IL-1β、COX-2水平，免疫组化检测软骨组织IL-1β、MMP-13蛋白表达，Western blot检测AMPK/NF-κB通路相关蛋白水平。结果 与Sham组比较，KOA组软骨组织损伤严重，膝关节宽度、Mankin评分、关节液TNF-α、IL-1β、COX-2水平及软骨组织IL-1β、MMP-13、p-NF-κB p65/NF-κB p65水平显著升高，疼痛阈值及软骨组织p-AMPK/AMPK水平显著降低(P<0.05);与KOA组比较，Ephedrine组软骨组织病理损伤减轻，膝关节宽度、Man...     

LINC00667调控NF-κB信号通路对高糖诱导的人近端肾小管上皮细胞EMT的影响

目的:探讨LINC00667对高糖诱导的人近端肾小管上皮细胞间充质转化(EMT)及核因子κB(NF-κB)信号通路的影响。方法:将人肾小管上皮细胞HK-2分为正常对照(NC)组、高糖(HG)组、HG+si-con组、HG+si-LINC00667组、HG+si-LINC00667+PBS组、HG+si-LINC00667+TNF-α组。实时荧光定量PCR(RT-qPCR)检测LINC00667的表达;酶联免疫吸附测定(ELISA)试剂盒检测白细胞介素1β(IL-1β)和转化生长因子(TGF-β_1)含量;蛋白质印记(Western blot)检测钙黏蛋白(E-cadherin)、波形蛋白(Vimentin)、α-平滑肌肌动蛋白(α-SMA)以及NF-κB信号通路相关蛋白的表达。结果:与NC组比较,HG组HK-2细胞LINC00667、Vimentin和α-SMA表达升高,E-cadherin表达降低,细胞培养液上清中IL-1β和TGF-β_1含量升高,NF-κB信号通路激活(P0.05)。与HG+si-con组比较,HG+si-LINC00667组HK-2细胞Vimentin和α-SMA表达降低,E-cadherin表达升高,细胞培养液上清中IL-1β和TGF-β_1含量降低,NF-κB信号通路受到抑制(P0.05)。与HG+si-LINC00667+PBS组比较,HG+si-LINC00667+TNF-α组HK-2细胞NF-κB信号通路激活,Vimentin和α-SMA表达升高,E-cadherin表达降低,细胞培养液上清中IL-1β和TGF-β_1含量升高(P0.05)。结论:沉默LINC00667可抑制高糖诱导的人近端肾小管上皮细胞EMT,抑制炎症反应,其机制与抑制NF-κB信号通路有关。     

胃癌细胞中miR-455-3p的表达及其对增殖和凋亡的影响

目的:探讨mi R-455-3p在胃癌细胞中的表达及对胃癌细胞增殖和凋亡的影响。方法:用q RT-PCR检测mi R-455-3p在正常胃黏膜上皮细胞RGM-1及5种胃癌细胞系(AGS、Hs746T、MGC-803、SGC-7901及BSG-823)中的表达。将胃癌细胞mi R-455-3p模拟物后,分别用CCK8法检测细胞增殖,流式细胞术检测细胞凋亡,Western blot检测细胞p27 kip1、p21的蛋白表达,分光光度法检测细胞caspase酶活性。结果:mi R-455-3p在5种胃癌细胞系中的表达水平明显低于RGM-1细胞系,其中在AGS细胞中降低最为明显(均P0.05)。AGS细胞转染mi R-455-3p模拟物后,增殖能力明显降低而胞凋亡率明显升高,p27 kip1蛋白表达量明显升高,caspase-3与caspase-9相对活性明显升高(均P0.05),但p21蛋白表达量与caspase-8相对活性无明显改变(均P0.05)。结论:mi R-455-3p在胃癌细胞表达下调,增加其表达可抑制胃癌细胞增殖并促进凋亡,其机制可能与其上调p27 kip1表达及增强caspase-3、caspase-9活性有关。     

山药多糖通过miR-98-5p/TGFβR1分子轴调控肝癌细胞凋亡的机制研究

目的探究山药多糖(CYPS)通过miR-98-5p/TGFβR1分子轴调控肝癌(HCC)细胞凋亡的分子机制。方法qPCR检测miR-98-5p在不同HCC细胞系中的表达情况,使用不同浓度的CYPS处理Huh-7细胞,CCK-8检测细胞增殖活力,Annexin V-FITC/PI流式细胞术检测细胞凋亡,Western blotting检测TGFβR1和细胞凋亡相关蛋白Caspase-3、Caspase-8、Bcl-2、Bax的表达,双荧光素酶报告基因系统验证miR-98-5p与TGFβR1的靶向关系。结果与人正常肝细胞HL-7702相比,miR-98-5p在HCC细胞系中表达升高(均P<0.05),且在Huh-7细胞中的表达高于其他HCC细胞(P<0.05);CYPS处理可明显抑制Huh-7细胞的增殖活力并诱导细胞凋亡(均P<0.05),且10-3 kg/L CYPS对细胞增殖活力的抑制作用比其他浓度明显。双荧光素酶报告基因实验证实,miR-98-5p靶向调控TGFβ1。与10-3 kg/L CYPS组相比,miR-98-5p mimics可下调10-3 kg/L CYPS对细胞增殖活力(P<0.05)的抑制作用和对细胞凋亡(P<0.01)的促进作用,CYPS+miR-98-5p mimics+pcDNA-TGFβR1组中细胞增殖活力与CYPS+miR-98-5p mimics组相比明显降低(P<0.05),细胞凋亡水平明显升高(P<0.01)。结论CYPS可下调miR-98-5p,促进TGFβR1的表达,抑制Huh-7细胞增殖并诱导细胞凋亡。     

miR-31-5p靶向Notch1调节骨关节炎软骨细胞增殖和凋亡的作用

目的明确miR-31-5p在骨关节炎软骨细胞中的作用。方法采用Hulth法进行大鼠骨关节炎造模,并分离原代软骨细胞,白细胞介素(interleukin,IL)-1β诱导体外模型,检测miR-31-5p的表达变化;进一步通过在线数据库预测miR-31-5p靶点并验证,细胞增殖检测试剂盒(cell counting kit-8,CCK-8)和流式细胞术检测miR-31-5p对原代软骨细胞增殖和凋亡的影响。结果骨关节炎大鼠中miR-31-5p表达下调;miR-31-5p mimics促进软骨细胞增殖,而miR-31-5p inhibitor诱导软骨细胞凋亡增加;此外,miR-31-5p inhibitor促进IL-6和基质金属蛋白酶13(matrix metalloprotein,MMP-13)表达增加;荧光素酶报告基因实验证实Notch1是miR-31-5p的直接靶点,Notch1过表达质粒会部分抵消miR-31-5p mimics对软骨细胞的增殖保护作用。结论miR-31-5p下调表达介导骨关节炎软骨细胞增殖受限和凋亡发生,可能参与骨关节炎的发病。     

MiR-702-3p inhibits the inflammatory injury in septic H9c2 cells by regulating NOD1

BackgroundCardiac insufficiency is a common complication of sepsis and septic shock and is the most common cause of death in critically ill patients. Recent studies have found that microRNAs (miRNAs) play a potential role in sepsis as markers, but little is known about their functional effects on sepsis-induced cardiomyopathy (SIC).ObjectiveThis study is designed to explore the possible role and underlying mechanisms of miR-702-3p in septic cardiomyopathy.MethodsAs expected, H9c2 cells were induced with lipopolysaccharide (LPS) to construct the model of septic cardiomyopathy. The expression of miR-702-3p was detected by qRT-PCR assay and those of IL-1β, IL-6 and TNF-α by ELISA assay. The viability, proliferation and apoptosis of LPS-treated H9c2 cells were determined by CCK-8, EdU, flow cytometry and western blot assays. Moreover, Nucleotide-binding oligomerization domain-containing protein 1 (NOD1) was predicted and confirmed as a direct target of miR-702-3p by TargetScan, miRwalk and miRDB prediction and dual-luciferase reporter gene assays.ResultsWhile LPS can weaken the viability of H9c2 cells, miR-702-3p enhances that of LPS-treated H9c2 cells by inhibit the expressions of TNF-α, IL-6, IL-1β. We found NOD1 is a target gene of miR-702-3p, and over-expression of NOD1 restores the inhibitory effects of miR-702-3p on the LPS-treated H9c2 cells.ConclusionMiR-702-3p played an important role in the pathogenesis of sepsis cardiomyopathy via targeting NOD1, suggesting that miR-702-3p may be a potential new target for the treatment of SIC.     

Cytokine induction of Fas gene expression in insulin-producing cells requires the transcription factors NF-kappaB and C/EBP

Fas-mediated cell death may play a role in the autoimmune destruction of pancreatic beta-cells in type 1 diabetes. beta-Cells do not express Fas under physiological conditions, but Fas mRNA and protein are induced in cytokine-exposed mouse and human islets, rendering the beta-cells susceptible to Fas ligand-induced apoptosis. The aim of the present study was to investigate the molecular regulation of Fas by cytokines in rat beta-cells and in insulin-producing RINm5F cells. Fas mRNA expression was increased 15-fold in fluorescence-activated cell sorting-purified rat beta-cells exposed to interleukin (IL)-1beta, whereas gamma-interferon had no effect. Transfection experiments of rat Fas promoter-luciferase reporter constructs into purified rat beta-cells and RINm5F insulinoma cells identified an IL-1beta-responsive region between nucleotides -223 and -54. Inactivation of two adjacent NF-kappaB and C/EBP sites in this region abolished IL-1beta-induced Fas promoter activity in RINm5F cells. Binding of NF-kappaB and C/EBP factors to their respective sites was confirmed by gel shift assays. In cotransfection experiments, NF-kappaB p65 transactivated the Fas promoter. NF-kappaB p50 and C/EBPbeta overexpression had no effect by themselves on the Fas promoter activity, but when cotransfected with p65, each factor inhibited transactivation by p65. These results suggest a critical role for NF-kappaB and C/EBP factors in cytokine-regulation of Fas expression in insulin-producing cells.     

河蚌提取物葡聚糖对软骨细胞Wnt通路的调控作用研究

目的 ：探讨河蚌肉提取物葡聚糖HBP-A（anodonta glucan HBP-A）对体外软骨细胞Wnt通路的调控作用。方法：体外培养大鼠软骨细胞,添加IL-1β（10 ng/ml）诱导分化,分为空白组,IL-1β组,IL-1β＋IWP-2（5μM,Wnt通路抑制剂）组,IL-1β＋HBP-A（0.3 mg/ml）组,IL-1β＋IWP-2＋HBP-A共5组培养,提取各组细胞RNA和蛋白,采用Rt-PCR检测各组细胞Wnt-3a、β-catenin（24、48、72 h）及MMP-13（72 h）的基因表达;采用Western-blot检测β-catenin、MMP-13、Sox-9和Coll-Ⅱ蛋白的表达水平（48 h）。结果：细胞经IL-1β诱导分化,Wnt-3a基因表达升高,β-catenin以及MMP-13基因和蛋白表达升高,Sox-9和Coll-Ⅱ蛋白表达下调。添加HBP-A干预可以抑制IL-1β诱导下软骨细胞Wnt-3a基因的高表达、β-catenin以及MMP-13基因和蛋白的高表达,上调Sox-9和Ⅱ型胶原蛋白的表达。IWP-2和HBP-A合用时,Wnt-3a、β-catenin基因以及β-catenin蛋白表达最低,Sox-9蛋白表达最高。结论：HBP-A可通过降低Wnt/β-catenin信号通路表达,延缓软骨细胞分化,并且可与Wnt抑制剂协同调节Wnt-3a、β-catenin和Sox-9因子的表达。     

miR-204-5p inhibits inflammation of synovial fibroblasts in osteoarthritis by suppressing FOXC1

BackgroundThe paper is aimed at uncovering the mechanism of miR-204-5p in regulating inflammatory responses of human osteoarthritic synovial fibroblasts (SFs).MethodsIL-1β-induced osteoarthritic SFs were established as an osteoarthritis (OA) cell model. The osteoarthritic SFs were accordingly transfected with mimics-miR-204-5p, inhibitors-miR-204-5 or FOXC1 siRNA. MTT tested the vitality of osteoarthritic SFs by analyzing the cell optical density. The expressions of miR-204-5p, FOXC1, TNF-α, IL-6, PGE2, MMP-1, MMP-13 and COX-2 in osteoarthritic SFs were measured by qRT-PCR, Western blotting and/or ELISA. The binding of miR-204-5p to FOXC1 was verified through luciferase reporter assay. The regulatory effect of miR-204-5p on FOXC1 was also tested in normal SFs.ResultsmiR-204-5p was under-expressed and FOXC1 was over-expressed in osteoarthritic SFs. The expressions of FOXC1, TNF-α, IL-6, PGE2, MMP-1, MMP-13 and COX-2 were up-regulated in IL-1β-treated SFs. Up-regulation of miR-204-5p or down-regulation of FOXC1 suppressed the inflammatory responses of osteoarthritic SFs. miR-204-5p negatively regulated FOXC1 by being a sponge in osteoarthritic SFs as well as in normal SFs.ConclusionmiR-204-5p down-regulates FOXC1 to ameliorate inflammation of SFs in OA.     

Involvement of CCAAT enhancer binding protein transcription factors in the regulation of prostaglandin G/H synthase 2 expression by interleukin-1 in osteoblastic MC3T3-E1 cells.

Interleukin-1 (IL-1) stimulates prostaglandin production in bone by a rapid and transient activation of prostaglandin G/H synthase 2 (PGHS-2) gene expression. In osteoblastic MC3T3-E1 cells, IL-1 caused a transient increase in PGHS-2 messenger RNA (mRNA), which peaked at 2 h. IL-1 caused a 2- to 4-fold activation of a 371-base pair (bp) murine PGHS-2 promoter/luciferase construct in stable transfectants. This response mapped to a proximal promoter element(s) located between -150 and -40 bp. This region contains a putative CCAAT enhancer binding protein (C/EBP) site (centered at -135 bp), which shows enhanced binding of C/EBPbeta and C/EBPdelta by mobility shift analysis after IL-1 treatment. A transient cotransfection approach was used to examine the effects of C/EBPbeta and C/EBPdelta overexpression. IL-1 caused a maximal 3- to 7-fold stimulation of PGHS-2 promoter activity after 2.5 h. Overexpression of murine C/EBPbeta and C/EBPdelta caused a dose-dependent increase in basal and IL-1-stimulated luciferase activity. C/EBPdelta caused a greater enhancement of basal and IL-1-stimulated promoter activity than C/EBPbeta, suggesting that C/EBPdelta is a stronger transactivator. Overexpression of p20C/EBPbeta, a dominant negative inhibitor of C/EBP function, blocked the stimulation of PGHS-2 promoter activity by IL-1 and blocked the ability of overexpressed C/EBPbeta and C/EBPdelta to increase basal and IL-1-stimulated promoter activity. Mutagenesis of the C/EBP site reduced, but did not abolish, the stimulation of PGHS-2 promoter activity by IL-1 and blunted the effect of overexpressed C/EBPdelta on basal and IL-1-stimulated promoter activity. These results suggest an essential role for C/EBPbeta and C/EBPdelta in the induction of PGHS-2 gene expression by IL-1 in osteoblastic cells.     

LINC01534/miR-135b-5p/PTPRT axis regulates inflammatory response in loosening total hip replacement via modulating NF-κB signaling pathway

Aseptic loosening after total hip replacement brings adverse health outcomes and increased risk for complications. The resorptive activity of inflammatory cells activated by the presence of wear-generated debris plays a critical role in debris-induced osteolysis. Previous studies indicate that the abnormally expressed LINC01534 plays a critical role in inflammatory responses. In this study, we aimed to elucidate the functional role and underlying mechanism of LINC01534 in debris-induced osteolysis. We first confirmed that LINC01534 was highly expressed in hip cartilage tissues from aseptic loosening patients. By using an IL-1β-induced inflammation model mimicking debris-induced osteolysis, we demonstrated that LINC01534 promoted IL-1β-induced inflammatory response in hip chondrocytes. Knockdown of LINC01534 inhibited the expression of inflammatory IL-6, IL-8, and TNF-α in hip chondrocytes. Our results showed that LINC01534 functioned as a competing endogenous RNA (ceRNA) by sponging miR-135b-5p in hip chondrocytes. Moreover, bioinformatics analysis and luciferase reporter assay demonstrated that CCHC-Type Zinc Finger Nucleic Acid Binding Protein (PTPRT) is a downstream target of miR-135b-5p. Knockdown of PTPRT attenuated the IL-1β-induced inflammatory responses in hip chondrocytes. In addition, we revealed that inhibition of miR-135b-5p or overexpression of PTPRT could antagonize the effects of LINC01534 knockdown on inflammation attenuation in hip chondrocytes. Mechanistically, we demonstrated that LINC01534/miR-135b-5p/PTPRT axis regulated the NF-κB signaling pathway in hip chondrocytes. Taken together, our findings suggest that LINC01534/miR-135b-5p/PTPRT axis might be a valuable therapeutic target for the treatment of debris-induced osteolysis.