柚皮苷对脂多糖诱导的人牙周膜成纤维细胞增殖及炎症因子表达的影响

目的探讨柚皮苷(naringin,NRG)对脂多糖诱导的人牙周膜成纤维细胞增殖及炎症因子表达的影响。方法以脂多糖(lipopolysaccharide,LPS)(100μg/mL)诱导人牙周膜成纤维细胞(human periodontal ligament fibroblast,HPDLF)损伤,采用MTT法检测NRG对LPS诱导HPDLF损伤的保护作用,利用ELISA法和Western blotting法检测NRG对LPS诱导的HPDLF中白介素(interleukin,IL)-6、IL-8、IL-1β等炎症因子蛋白表达的影响,同时利用Real-time PCR方法检测NRG对LPS诱导的HPDLF组IL-6、IL-8、IL-1β等炎症因子基因表达的影响。结果经LPS(100μg/mL)刺激后,HPDLF增殖受到抑制,与CON组比较,LPS组细胞存活率显著降低,细胞周期进程受到抑制,差异具有统计学意义(P<0.05);不同浓度的NRG(40,20,10μg/mL)可显著抑制LPS诱导的HPDLF损伤,并可降低细胞内炎症因子表达;与LSP组比较,LPS+NRG 40μg/mL组、LPS+NRG 20μg/mL组、LPS+NRG 10μg/mL组HPDLF存活率显著提升,细胞周期进程加快,抑制IL-6、IL-8、IL-1β蛋白及基因表达水平均显著降低,差异具有统计学意义(P<0.05)。结论NRG对LPS诱导的HPDLF损伤具有保护作用,并可通过抑制LPS诱导的HPDLF中IL-6、IL-8、IL-1β的蛋白及基因表达水平,促进HPDLF增殖。     

槲皮素对牙龈卟啉单胞菌脂多糖刺激的人牙龈成纤维细胞生物学行为的影响研究

目的研究槲皮素对牙龈卟啉单胞菌脂多糖(Porphyromonas gingivalis lipopolysaccharide,P.g LPS)刺激的人牙龈成纤维细胞(human gingival fibroblasts,HGFs)生物学行为的影响。方法采用DNA片段凝胶电泳、CCK-8法、细胞划痕法观察不同浓度槲皮素(10、20、50、100μmol/L)对体外培养HGFs的毒性作用,以及对HGFs增殖与迁移的影响。采用P.g LPS刺激HGFs来建立体外炎症刺激模型,通过流式细胞术、细胞活性氧(reactive oxygen species,ROS)检测、酶联免疫吸附试验(ELISA)和实时荧光定量PCR(qRT-PCR)进一步观察槲皮素对HGFs凋亡、ROS的产生及肿瘤坏死因子-α(tumor necrosis factorα,TNF-α)和前列腺素E2(prostaglandin E2,PGE2)表达的影响。结果槲皮素对HGFs无毒性作用,且对HGFs的增殖无影响(P>0.05)。各组细胞迁移率总的比较,差异有统计学意义(F=9.973,P<0.05),在处理48 h后,20μmol/L槲皮素处理组细胞迁移率大于10、50μmol/L槲皮素处理组以及对照组,差异均有统计学意义(均P<0.05)。槲皮素对P.g LPS刺激的HGFs凋亡具有抑制作用,且其能够抑制并预防P.g LPS刺激的HGFs中ROS相对产生量增加现象(均P<0.05)。槲皮素处理显著抑制了P.g LPS诱导的TNF-α表达增加现象(P<0.05),而槲皮素处理组PGE2的表达水平与对照组比较,差异无统计学意义(P>0.05)。结论浓度为20μmol/L的槲皮素能够促进体外培养HGFs的迁移,且具有抗氧化、抗炎保护作用。     

脂多糖和白细胞介素-1β对人牙周膜细胞中诱导型一氧化氮合酶表达的影响

目的观察脂多糖(LPS)和白细胞介素-1β(IL-1β)对人牙周膜细胞(hPDLCs)表达诱导型一氧化氮合酶(iNOS)和一氧化氮(NO)的影响。方法应用LPS和IL-1β刺激hPDLCs后,通过实时定量PCR检测iNOS基因的表达情况,收集细胞上清液,酶联免疫吸附试验(ELISA)测定诱导后细胞中iNOS的含量变化,采用硝酸还原酶法检测NO的表达水平。结果未受刺激的hPDLCs仅能产生微量的iNOS和NO;LPS和IL-1β刺激hPDLCs后,检测到iNOS、iNOS mRNA及NO的含量随着时间和质量浓度的增加而显著增加(P<0.05),在相同时间或相同质量浓度的条件下,IL-1β单独刺激或与LPS联合刺激hPDLCs产生iNOS及NO的能力强于LPS单独刺激(P<0.05)。结论 LPS和IL-1β刺激hPDLCs可以增加iNOS和NO的表达,为动物实验中牙周局部注射LPS和IL-1β诱导iNOS和NO表达奠定实验基础。     

红景天苷对LPS刺激人牙周膜细胞增殖和分泌表达的影响

目的研究红景天苷(salidroside,SAL)对大肠杆菌脂多糖(lipopolysaccharide,LPS)刺激后体外培养人牙周膜细胞(human periodontal ligament cells,h PDLCs)的增殖及对分泌表达Toll样受体(Toll-like receptor 4,TLR 4)、肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)、白介素-1β(interleukin-1β,IL-1β)、白细胞介素-6(interleukin-6,IL-6)、骨保护素(osteoprotegerin,OPG)及核因子-κB受体活化因子配体(receptor activator of NF-κB ligand,RANKL)的影响,为红景天苷在牙周炎治疗方面提供初步的实验依据。方法组织块法原代培养正常h PDLCs;以2 mg/L LPS刺激第4代细胞,加入不同浓度的红景天苷作用12、24、48 h;采用MTT方法检测细胞的增殖;采用Western blot、ELISA、qRT-PCR等方法检侧TLR-4、TNF-α、IL-1β、IL-6、OPG及RANKL的表达水平,并进行统计学分析。结果 MTT结果显示低浓度的红景天苷(≤10μmol/L)均能促进细胞增殖,并存在浓度依赖性,其中0.5μmol/L对h PDLCs增殖作用最明显(P<0.05),高浓度的红景天苷(>10μmol/L)不能促进牙周膜细胞增殖;Western blot、ELISA及qRT-PCR结果显示:0.5μmol/L红景天苷可使LPS刺激的h PDLCs的TLR4、TNF-α、IL-1β、IL-6及RANK表达水平随时间延长而逐渐降低,其中48 h降低的最为明显,存在显著性差异(P<0.05);另外,LPS刺激对OPG的表达几乎没有影响,而0.5μmol/L红景天苷作用可以显著上调OPG的表达水平。结论红景天苷可减轻LPS刺激后h PDLCs的细胞损伤,其机制可能通过调节与TLR4相关信号通路,降低炎症因子TNF-α、IL-1β、IL-6及与骨吸收相关因子RANKL、OPG的表达,从而抑制炎症反应和骨吸收。     

氧化苦参碱对内毒素作用下人牙周膜细胞白细胞介素-6和白细胞介素-1β mRNA表达的影响

目的 研究氧化苦参碱对内毒素(LPS)作用下人牙周膜细胞(PDLC)白细胞介素-6(IL-6)和白细胞介素-1β(IL-1β)mRNA表达的影响,探讨氧化苦参碱抑制LPS所造成的牙周炎症反应的机制.方法 体外分离及培养PDLC,实验组分别为LPS和不同质量浓度的氧化苦参碱溶液的不同组合,对照组为仅含1%FBS的DMEM培养液.采用逆转录聚合酶链反应(RT-PCR)检测IL-6和IL-1β mRNA的水平.结果 质量浓度为25 μg·mL-1 LPS能够有效地增强IL-6和IL-1β mRNA水平的表达,实验组高于对照组,差异有统计学意义,加入氧化苦参碱进行干预后实验组与对照组IL-6和IL-1β mRNA的表达无显著差异.结论 氧化苦参碱可抑制LPS所造成的PDLC IL-6和IL-1β mRNA表达.     

LPS刺激对体外培养人牙周膜细胞产生IL-8和MCP-1的影响

目的:检测脂多糖(LPS)刺激对体外培养人牙周膜细胞分泌炎症趋化因子IL-8和MCP-1改变的影响.方法:组织块法原代培养人牙周膜细胞,MTT法观察不同浓度LPS对其增殖的影响;取第4代牙周膜细胞在10 μg/mL LPS刺激条件下进行培养,分别于培养后4、8、12、24 h用酶联免疫吸附(ELISA)法检测牙周膜细胞培养上清中IL-8和MCP-1的含量;结果采用单因素方差进行统计分析.结果:10 μg/mL LPS刺激可使牙周膜细胞的增殖速度略减低,刺激后24 h内细胞形态和数量未见明显变化.ELISA结果显示LPS刺激后牙周膜细胞在10 μg/mL培养上清中IL-8和MCP-1含量均明显高于对照组(P＜0.05);且两种蛋白含量均随培养时间延长而增加(P＜0.05),呈时间依赖性.结论:10μg/mL LPS刺激可使牙周膜细胞培养上清中IL-8和MCP-1含量呈时间依赖性增加,提示牙周膜细胞具有免疫调节功能.     

淫羊藿苷对人牙周膜细胞增殖及内毒素作用下IL-6表达的影响

目的初步研究淫羊藿苷对人牙周膜细胞(human periodontal ligament cells,h PDLC)增殖以及在内毒素(Lipopolysaccharide,LPS)作用下淫羊藿苷对h PDLC白细胞介素6(IL-6)表达的影响。方法组织块法原代培养并鉴定h PDLC,采用MTT方法检测淫羊藿苷(0、10-5、10-6、10-7、10-8、10-9、10-10mol/L)作用下h PDLC增殖的变化;利用PCR、ELISA方法检测淫羊藿苷对在LPS刺激下的人牙周膜细胞IL-6分泌的情况。结果一定浓度范围下(10-6~10-7mol/L)淫羊藿苷对h PDLC的增殖具有积极作用;在10μg/m L LPS作用下h PDLC的IL-6表达增多、活性增强,加入10-6mol/L淫羊藿苷处理后,对此加强效果有一定的抑制作用。结论在一定浓度范围作用下淫羊藿苷可促进h PDLC的增殖;同时,淫羊藿苷对LPS导致h PDLC的IL-6表达增强有一定的抑制作用。     

白细胞介素-10对人牙龈成纤维细胞分泌白细胞介素-1β的抑制作用

目的:探讨白细胞介素-10(IL-10)在牙周炎症反应中的抑制作用。方法:用细胞培养法、酶联免疫吸附分析法 (ELISA)检测细胞培养液上清中的IL-1B浓度;用MTT法检测人牙龈成纤维细胞(HGF)对细菌脂多糖(LPS)、IL-10的增殖反应。结果:LPS以剂量依赖方式诱导HGF产生IL-1B,6 h达最大分泌量;IL-1B的分泌可被IL-10抑制,10 ng/ ml IL-10作用24 h抑制效应达最大;LPS对HGF具有促增殖作用,而IL-10对HGF的增殖无影响。结论:IL-10是一种抑制牙周炎症反应的细胞因子。     

黄芩苷对内毒素作用的人牙周膜细胞增殖和分泌肿瘤坏死因子-α的影响

目的:观察野黄芩苷对内毒素脂多糖(LPS)作用的人牙周膜细胞增殖和分泌肿瘤坏死因子-α的影响.方法:原代培养人牙周膜细胞,采用MTT比色法观察野黄芩苷对LPS作用的人牙周膜细胞增殖活性的影响,采用酶联免疫方法检测培养上清液中的TNF-α水平.结果: 100 μg/ ml LPS可抑制人牙周膜细胞的增殖活性、刺激人牙周膜细胞分泌肿瘤坏死因子-α.加入LPS同时分别给予0.001～10 μg/ ml不同浓度野黄芩苷,能促进人牙周膜细胞的增殖活性并能抑制LPS刺激人牙周膜细胞肿瘤坏死因子-α的分泌,其中在1 μg/ ml时作用达到最强.结论:野黄芩苷对LPS作用的人牙周膜细胞具有保护作用.     

脂多糖和白细胞介素-1β对人牙周膜细胞中诱导型一氧化氮合酶表达的影响

目的 观察脂多糖(LPS)和白细胞介素-1β(IL-1β)对人牙周膜细胞(hPDLCs)表达诱导型一氧化氮合酶(iGNOS)和一氧化氮(NO)的影响.方法 应用LPS和IL-1β刺激hPDLCs后,通过实时定量PCR检测iNOS基因的表达情况,收集细胞上清液,酶联免疫吸附试验(ELISA)测定诱导后细胞中iNOS的含量...     

A20对IL-17介导人牙周膜细胞RANKL表达影响

目的探究A20对IL-17调控人牙周膜细胞表面RANKL表达的影响。方法转染人牙周膜细胞(h PDLCs)A20siRNA、慢病毒,获得A20沉默/过表达h PDLCs,分为沉默组、正常组、过表达组,IL-17(50 ng/ml)刺激一定时间,ELISA,PCR,Western-blot检测RANKL表达。结果 A20沉默组的h PDLCs RANKL蛋白表达水平较正常对照组高,A20过表达组较正常对照组低,IL-17(50ng/ml)刺激下,A20沉默组较正常对照组RANKL表达水平高,过表达组较正常对照组低。结论本研究首次发现A20可能参与调控IL-17引起的h PDLCs RANKL表达。     

The Proteasome Inhibitor Bortezomib Inhibits Inflammatory Response of Periodontal Ligament Cells and Ameliorates Experimental Periodontitis in Rats

Background: Periodontitis is a chronic inflammatory disease initiated by bacteria and their virulence factors. Bortezomib (BTZ) is the first proteasome inhibitor for clinical treatment of malignancies. Its anticancer activity is accompanied by an anti‐inflammatory effect. However, there are few reports about its anti‐inflammatory effect and underlying mechanism in periodontal disease, especially on human periodontal ligament cells (hPDLCs), which are considered a promising cell‐based therapy for treating periodontitis. Methods: hPDLCs were treated with lipopolysaccharide (LPS) and pretreated with BTZ. mRNA and protein levels of tumor necrosis factor (TNF)‐alpha, interleukin (IL)‐1β, IL‐6, and IL‐8 were determined. The anti‐inflammatory mechanism of BTZ was studied. Further, experimental rat periodontitis was induced with ligature and LPS injection, and simultaneously and locally treated with BTZ (three injections/week). Four weeks after treatment, microcomputed tomography, immunohistochemical, and histopathologic analyses were performed. Results: Bortezomib administration at safe concentrations (≤1 nM) inhibited production of proinflammatory cytokines in LPS‐stimulated hPDLCs via nuclear factor (NF)‐kappa B, p38/extracellular signal‐regulated kinase, and mitogen‐activated protein kinase/activator protein‐1 pathways. Moreover, in the LPS and ligature‐induced periodontitis rat model, BTZ suppressed expression of TNF‐α, IL‐1β, IL‐6, and IL‐8, reduced the ratio of receptor activator of NF‐κB ligand/osteoprotegerin, and prevented alveolar bone absorption. Conclusion: These findings demonstrate the anti‐inflammatory activity of BTZ against periodontal inflammatory response and present BTZ as a promising therapy for periodontal disease.     

氢气对脂多糖致人牙周膜细胞氧化应激损伤的保护作用

目的 研究培养基中加入氢气能否对人牙周膜细胞（hPDLCs）在脂多糖（LPS）刺激下起到保护作用,降低氧化应激损伤,减少细胞凋亡。方法 用1 μg·mL^-1 LPS刺激hPDLCs,分别用普通和富氢培养基培养,检测2组细胞的增殖,凋亡和细胞上清中超氧化物歧化酶（SOD）、过氧化氢酶（CAT）和丙二醛（MDA）水平。结果 在LPS刺激下,富氢培养基组细胞增殖活性显著高于普通培养基组,凋亡率降低（P<0.05）。2组间LDH释放量差异无统计学意义。6 h和12 h富氢培养基组细胞上清中CAT活性较普通培养基组显著升高（分别为P<0.05,P<0.01）;而2组的SOD水平在各个时间点均无统计学差异。6 h富氢培养基组细胞上清中MDA水平较普通培养基组显著降低（P<0.05）。结论 氢气可有效改善LPS导致的hPDLCs增殖活性降低及凋亡,并可显著降低氧化应激损伤。     

Upregulated Leptin in Periodontitis Promotes Inflammatory Cytokine Expression in Periodontal Ligament Cells

Background: Imbalance or disruption in the expression of inflammatory mediators contributes greatly to the breakdown of the periodontal supporting tissues. Leptin, through binding to its receptor (obesity‐related leptin and leptin receptor [OBR]), has potent effects on immunity and inflammation. However, to date, researchers only indicated a role of leptin in periodontitis. No direct or valid evidence exists about how leptin and its receptor are regulated by local inflammation, what effects they have, and the underlying mechanisms. Methods: Experimental periodontitis was induced by ligation of mandibular second molars in beagle dogs. The expression of leptin, OBR, and interleukin (IL)‐1β was examined by immunohistochemistry. Meanwhile, recombinant human IL‐1β was used to stimulate human periodontal ligament cells (hPDLCs) in vitro, and mRNA and protein levels of leptin were measured using real‐time polymerase chain reaction (PCR) and enzyme‐linked immunosorbent assay (ELISA), respectively. Then, mRNA and protein levels of IL‐6 and IL‐8 were measured using real‐time PCR and ELISA, after stimulation with various concentrations of leptin, knocking down all or only the long form of OBR (OBRb) by small interfering RNA and incubation with multiple intracellular signaling pathway inhibitors, respectively. Results: Leptin and OBR increased substantially in inflammatory periodontal tissues, which correlated well with the extent of inflammatory infiltration, and was a result of the upregulation in resident cells themselves. A high dose of leptin could induce the expression of mRNA and protein of IL‐6 and IL‐8 in hPDLCs through binding with OBRb and activating different intracellular signaling pathways. Conclusion: Upregulated leptin and OBR in periodontitis stimulated proinflammatory cytokine expression in PDL cells to additionally promote local inflammation.     

Human periodontal ligament cells exhibit no endotoxin tolerance upon stimulation with Porphyromonas gingivalis lipopolysaccharide

Background/Objectives

Endotoxin tolerance is characterized by a state of hyporesponsiveness after confrontation with endotoxins such as lipopolysaccharides (LPS) at low concentrations. The aim of this study was to investigate, whether pretreatment with Porphyromonas gingivalis leads to endotoxin tolerance induction and possible alterations in toll‐like receptor (TLR) 2‐ and 4‐induced response in human periodontal ligament cells (hPDLCs).

Material and Methods

Primary hPDLCs were pretreated with P. gingivalis (0.1 or 0.3 μg/mL) LPS for 24 hours and afterwards treated with one of the following stimuli: P. gingivalis LPS (1 μg/mL); TLR4 agonist Escherichia coli LPS (0.1 μg/mL; 1 μg/mL); TLR2 agonist Pam3CSK4 (0.1 μg/mL; 1 μg/mL). The protein expression of interleukin (IL)‐6, IL‐8 and monocyte chemotactic protein‐1 was analyzed with quantitative polymerase chain reaction and enzyme‐linked immunosorbent assay. Gene expression levels of TLR2 and TLR4 were determined by quantitative polymerase chain reaction.

Results

Pretreatment of cells with low concentrations of P. gingivalis LPS did not result in lower production of IL‐6, IL‐8 and monocyte chemotactic protein‐1 compared to control group. In some cases, pretreated cells exhibited lower gene expression levels of TLR2 and TLR4 compared to non‐pretreated cells.

Conclusion

The results of this study implicate that hPDLCs do not develop endotoxin tolerance. Furthermore, the amplitude of the inflammatory response shows no significant dependency on TLR2 and TLR4 expression levels.     

乳铁蛋白下调脂多糖激发的人牙周膜细胞Toll样受体4表达的研究

目的 观察乳铁蛋白（LF）对经脂多糖（LPS）刺激的人牙周膜细胞（hPDLCs）表达Toll样受体4（TLR4）的影响。方法 采用组织块酶消化法培养hPDLCs,鉴定后取第4代细胞,分成空白对照组、LPS组、LPS+LF组。空白对照组不加任何刺激,LPS组加入0.1 μg?mL-1 LPS;LPS+LF组在加入0.1 μg?mL-1 LPS 2 h后,加入10 μg?mL-1 LF。以加入LF时开始计算时间,4 h后采用实时定量聚合酶链反应（RT-PCR）法检测hPDLCs中TLR4 mRNA的表达,24 h后采用细胞免疫荧光染色法观察TLR4蛋白的表达。结果 RT-PCR检测显示：LPS+LF组TLR4 mRNA表达较LPS组明显降低（P<0.05）,与空白对照组无明显差异（P>0.05）。细胞免疫荧光染色法显示：LPS+LF组TLR4蛋白的表达强度较LPS组减弱（P<0.05）,与空白对照组无明显差别（P>0.05）。结论 LF可以下调LPS激发的hPDLCs中TLR4的表达,在牙周炎症TLR4信号通路的调控过程中有一定的作用。     

白藜芦醇减轻LPS诱导的牙周膜细胞损伤并抑制TLR4/NF-κB活化

目的:探究白藜芦醇(RES)对脂多糖(LPS)诱导的人牙周膜细胞(hPDLCs)损伤的保护作用.方法:体外培养并鉴定hPDLCs,将培养的hPDLCs随机分为5组:对照组、LPS(10 μg/ml)+RES(0、30、60、90tμmol/L)组,MTT法检测各组细胞增殖能力,ELISA检测各组细胞分泌TNF-α/IL-6水平,PCR和Western blot检测各组细胞TLR4/NF-κB mRNA和蛋白表达.结果:分离培养的hPDLCs抗波丝蛋白表达阳性,抗角蛋白表达阴性.与对照组比,LPS处理后细胞增殖能力明显降低,细胞分泌TNF-α/IL-6水平和TLR4/NF-κB mRNA和蛋白表达明显增加;30～90 μmol/L白藜芦醇预处理后,细胞增殖能力增加(P＜0.05),细胞分泌TNF-α/IL-6水平、TLR4/NF-κB mRNA以及蛋白表达则下调(P＜0.05),均呈现一定的浓度依赖性.结论:白藜芦醇可抑制TLR4/NF-κB活化并减轻LPS诱导的牙周膜细胞损伤.