牙龈卟啉单胞菌感染对hPDL细胞中成骨标志基因表达及炎症因子分泌的影响

目的观察牙龈卟啉单胞菌(P.gingivalis)感染对人牙周膜(hPDL)细胞中成骨标志基因表达及炎症因子分泌的影响。方法原代hPDL细胞,分为P.gingivalis感染的P.gingivalis组、常规处理的对照组,成骨诱导后茜素红染色检测矿化结节,PCR法检测成骨标志基因Runt相关转录因子2(RUNX2)、骨钙素(OCN)、骨保护素(OPG)、骨碱性磷酸酶(BALP)的mRNA表达量,ELISA法检测炎症因子肿瘤坏死因子-α(TNF-α)、白细胞介素(IL)-1β、IL-6的分泌量,Western blot检测核因子-κB(NF-κB)及NF-κB抑制蛋白(I-κB)的蛋白表达量。结果与对照组比较,P.gingivalis组细胞成骨诱导后茜素红染色的矿化结节明显减少,细胞中RUNX2、OCN、OPG、BALP的mRNA表达量及I-κB的蛋白表达量均明显降低,培养基中TNF-α、IL-1β、IL-6的分泌量及细胞中NF-κB的蛋白表达量均明显增加。结论 P.gingivalis感染hPDL细胞后能够抑制成骨分化、激活炎症反应且该作用与NF-κB通路的激活有关。     

牙龈卟啉单胞菌感染通过Wnt通路调节牙周膜干细胞的成骨分化

目的观察牙龈卟啉单胞菌(P.gingivalis)感染通过Wnt通路调节牙周膜干细胞(PDLSCs)成骨分化的作用。方法培养原代PDLSCs,分为常规处理的对照组、P.gingivalis感染的P.gingivalis组和P.gingivalis感染并用Wnt3a处理的P.gingivalis+Wnt3a组,成骨诱导后茜素红染色并检测A_(405)值,Western blot检测Wnt通路分子的蛋白表达量,碱性磷酸酶(ALP)试剂盒检测ALP活力,PCR检测成骨标志基因Runt相关转录因子2(Runx2)、骨钙素(OCN)的mRNA表达量。结果与对照组比较,P.gingivalis组Wnt3a、β-catenin、p-GSK-3β的蛋白表达水平(0.33±0.07)、(0.27±0.08)、(0.44±0.09)以及成骨诱导后A_(405)值(0.55±0.08)、ALP活力(20.14±6.54)U/mL和Runx2、OCN的mRNA表达量(0.45±0.09)、(0.51±0.07)均明显减少;与P.gingivalis组比较,P.gingivalis+Wnt3a组成骨诱导后A_(405)值(0.89±0.15)、ALP活力(29.44±5.26)U/mL及Runx2、OCN的mRNA表达量(0.89±0.17)、(0.81±0.18)均明显增加。结论 P.gingivalis感染能够抑制PDLSCs的成骨分化,抑制Wnt通路是可能的分子机制。     

Wnt5a、Ror2在骨肉瘤中的表达及临床意义

目的:探讨骨肉瘤组织中Wnt5a、Ror2表达。方法:免疫组织化学法检测Wnt5a、Ror2在实验组55例骨肉瘤和对照组15例骨软骨瘤组织标本中的表达。结果:Wnt5a、Ror2在骨肉瘤组的表达均明显高于骨软骨瘤组(Wnt5a:74.55%、20.00%,Ror2:13.33%、70.91%,P0.05)。Wnt5a、Ror2在骨肉瘤出现转移的表达明显高于未转移(Wnt5a:100%、66.67%,Ror2:100%、61.90%,P0.05),在骨肉瘤Enneking分期中,Wnt5aⅠ期11.11%,Ⅱ期84.38%,Ⅲ期100.00%,Ror2Ⅰ期22.22%,Ⅱ期72.73%,Ⅲ期100.00%,Ⅰ期与Ⅱ期间和Ⅰ期与Ⅲ期间差异皆有统计学意义(P0.05),而Ⅱ期与Ⅲ期间差异皆无统计学意义(P0.05),Wnt5a、Ror2两者之间的表达呈正相关分布(骨肉瘤组:r=0.844,P0.01;骨软骨瘤组:r=0.808,P0.01),但在骨肉瘤患者性别、年龄以及骨肉瘤病理分型组中表达无明显差异(P0.05)。结论:Wnt5a、Ror2在骨肉瘤中存在高度表达,可能具有促癌作用,并与其恶性程度和侵袭转移有关,二者协同作用。     

PCL/β-TCP调控巨噬细胞极化对成血管效应的影响

目的:探究生物可降解材料聚己内酯/β-磷酸三钙(PCL/β-TCP)通过调控巨噬细胞极化对骨组织内血管生成的作用,为其临床应用提供依据。方法:采用3D打印技术制备试样并加以表征。体内实验采用模型为SD大鼠股骨远端植入模型。双侧植入PCL/β-TCP支架后采取免疫荧光染色观察支架内部成血管标记物CD31的表达差异,并采用血管灌注方法进行血管造影,评价支架内部血管体积。采用免疫荧光染色检测炎症标记物iNOS,抑炎标记物Arg-1的表达情况。体外实验采用细胞共培养的方式检测PCL/β-TCP对巨噬细胞极化的调控作用以及免疫介导的血管形成改变。实验分为两组,空白组(Control)及PCL/β-TCP(PT5)组。将巨噬细胞系Raw264.7接种于材料表面并对其极化水平及分泌改变进行检测。通过免疫荧光染色检测M1巨噬细胞标记物iNOS、M2巨噬细胞标记物Arg-1的表达情况。通过RT-qPCR检测CCR-7,CD206,血管内皮生长因子(VEGF),血小板源性生长因子(PDGF-BB),肿瘤坏死因子α(TNF-α),白细胞介素-10(IL-10)的转录情况。酶联免疫吸附试验(ELISA)检测VEGF、PDGF-BB、IL-10、TNF-α的分泌情况。应用Transwell迁移实验检测PCL/β-TCP刺激下巨噬细胞分泌作用对人脐静脉内皮细胞(HUVECs)迁移能力的影响,应用免疫荧光染色检测PCL/β-TCP刺激下巨噬细胞分泌作用对HUVECs表面血管形成指标CD31表达情况的影响。结果:在体内实验中,支架周围组织CD31表达升高(P0.001),血管灌注结果提示支架内部血管体积显著增加(P0.001),同时炎症标记物iNOS表达下调(P0.001),抗炎标记物Arg-1升高(P0.001)。在体外实验中,与Control相比,PT5组巨噬细胞中炎症标记物iNOS合成无明显差异,抑炎标记物Arg-1合成增加;炎症标记物CCR-7及TNF-α转录水平下调(P0.01,P0.01),抗炎标记物CD206及IL-10转录上调(P0.001,P0.001);VEGF转录水平下调(P0.01),PDGF-BB转录上调(P0.01);VEGF分泌水平下降(P0.001),PDGF-BB分泌增加(P0.01),IL-10分泌水平提高(P0.001),TNF-α分泌水平下降(P0.05)。在巨噬细胞分泌作用下,HUVECs的迁移能力提高(P0.001),CD31表达上调(P0.001)。结论:骨修复材料PCL/β-TCP可通过调控巨噬细胞向M2方向极化进而促进血管形成,可作为骨修复材料的候选材料之一。     

乙酰水杨酸预处理骨髓间充质干细胞对实验性牙周炎大鼠的治疗作用

本研究旨在探讨应用乙酰水杨酸(ASA)预处理的骨髓间充质干细胞(BMMSCs)治疗对大鼠牙周炎模型中的牙周骨修复的影响。通过建立大鼠牙周炎动物模型并使用ASA和BMMSCs联和治疗大鼠,本研究检测了体外BMMSCs的成骨分化、成脂分化、碱性磷酸酶(ALP)活性及成骨相关基因(ALP和OCN)的表达,并检测大鼠相关炎症因子(TNF-α,IL-17和IL-10)水平。结果显示,使用成骨培养基诱导BMMSCs后,可清晰地观察到BMMSCs的成骨分化和成脂分化。体外研究显示,60μg/mL的ASA显著促进了体外BMMSCs的增殖,提高了碱性磷酸酶(ALP)活性,促进了钙沉积和上调了成骨相关基因(ALP和OCN)的表达。此外,与未治疗的牙周炎大鼠比较,经ASA-BMMSCs治疗的牙周炎大鼠的TNF-α和IL-17水平显著下降,而IL-10显著升高。本研究表明,60μg/mL的ASA显著促进了体外BMMSCs的增殖和成骨分化。ASA和BMMSCs联用能够调节大鼠体内相关细胞因子的表达,并减轻炎症反应,可能是牙周炎治疗和牙周骨再生的有效方法。     

低氧对巨噬细胞分泌TNF-α和IL-6的影响及其机制

目的:观察低氧对巨噬细胞(Mφ)前炎症因子TNF-α和IL-6分泌的影响及其机制.方法:收集分离小鼠腹腔Mφ,建立Mφ的低氧(1% O2,5%CO2)培养模型,并用非特异性酯酶染色法进行鉴定;ELISA法检测上清液中TNF-α和IL-6的含量;RT-PCR法检测TNF-α和IL-6的转录物水平;用Western blot法检测Mφ核内NF-κB的激活量;通过在培养液中加入氢化可的松(5 mg/L),观察低氧时TNF-α和IL-6分泌量的变化.结果:TNF-α和IL-6分泌量在低氧12 h时明显增加(P＜0.01);低氧6 h时,TNF-α mRNA和IL-6 mRNA表达量明显高于对照组(P＜0.01);M中核内NF-κB的激活量在低氧2 h时明显增高(P＜0.05),低氧5 h内持续存在;而当培养液中加入氢化可的松抑制NF-κB活性后,TNF-α和IL-6的分泌水平无明显变化.结论:低氧可通过核转录因子NF-κB途径促进细胞因子TNF-α和IL-6基因的表达和分泌.     

球形孢子丝菌刺激小鼠树突状细胞表达前炎症细胞因子的研究

目的本研究旨在观察分离于新疆的球形孢子丝菌临床株刺激小鼠树突状细胞(Dendritic cells,DCs)后不同炎症因子分泌表达的特征,初步预测这些炎症因子的功能。方法菌株来源于淋巴管型孢子丝菌病患者。将该菌配置成不同浓度的菌悬液(1×10~4个/mL～1×10~7个/mL),刺激小鼠DC(细胞悬浮液浓度1×10~6细胞/mL),分别收集6 h、24 h、48 h、72 h时细胞培养上清液,采用酶免法检测IL-1β、IL-6、IL-4、TNF-α、IFN-γ的含量表达。结果以最低浓度菌液(1×10~4个/mL)刺激DC,被刺激后的DC分泌了IL-1β、IL-6和TNF-α,不同时间点分泌量分别为:IL-1β(6 h:21.26±3.03;24 h:24.04±4.25;48 h:24.90±4.31;72 h:27.29±6.09)、IL-6(6 h:44.38±3.73;24 h:101.72±12.28;48 h:133.10±8.67;72 h:180.38±13.84)、TNF-α(6 h:860.36±20.64;24 h:356.03±11.46;48 h:457.43±17.39;72 h:1454.53±19.46),但是IFN-γ和IL-4未见分泌表达。IL-1β和IL-6分泌水平有随时间和剂量依赖而逐渐增高,但是TNF-α释放量呈现不规律表达。结论 DC参与了球形孢子丝菌感染的天然免疫应答,分泌的关键炎症因子是IL-1β、IL-6、和TNF-α,表达量为TNF-α IL-6 IL-1β。其中IL-1β和IL-6分泌表达量具有时间和剂量依赖性。     

双氢杨梅素对缺氧诱导的心肌细胞炎症反应和凋亡的影响及机制

目的:探讨双氢杨梅素对缺氧诱导的心肌细胞炎症和凋亡的影响及其可能调控机制。方法:将心肌细胞(H9C2细胞系)缺氧处理建立细胞模型,随机分为4组:对照组、对照+双氢杨梅素组、缺氧组、缺氧+双氢杨梅素组。对照+双氢杨梅素组和缺氧+双氢杨梅素组分别加入5μmol/L的双氢杨梅素孵育24 h,对照组和缺氧组分别加入同等体积的DMSO孵育24 h。实时PCR检测心肌细胞CD40、IL-1β、IL-6、TNF-α、mi RNA-145-5p的m RNA水平;ELISA检测IL-1β、IL-6和TNF-α的浓度;MTT实验检测心肌细胞生存率;Tunel法检测心肌细胞凋亡;Western blot检测心肌细胞Cleaved Caspase3的表达。结果:与对照组和对照+双氢杨梅素组相比,缺氧组CD40、IL-1β、IL-6、TNF-α的m RNA水平升高(P0.05),IL-1β、IL-6、TNF-α浓度显著升高(P0.05),mi RNA-145-5p的m RNA水平显著降低(P0.05),心肌细胞生存率显著降低(P0.05),心肌细胞凋亡显著增加(P0.05),Cleaved Caspase3的蛋白表达显著增加;与缺氧组相比,缺氧+双氢杨梅素组CD40、IL-1β、IL-6、TNF-α的m RNA水平显著降低(P0.05),IL-1β、IL-6、TNF-α浓度显著降低(P0.05),mi RNA-145-5p的m RNA水平显著增加(P0.05),心肌细胞生存率显著增加(P0.05),心肌细胞凋亡显著降低(P0.05),Cleaved Caspase3的蛋白表达显著降低。结论:双氢杨梅素可抑制缺氧诱导的心肌细胞炎症和凋亡,其机制可能与双氢杨梅素上调mi RNA-145-5p进一步抑制CD40介导的炎症反应和凋亡有关。     

IL-27增强TNF-α介导上调的炎症因子的表达

目的:动脉粥样硬化是慢性炎症疾病,免疫细胞及炎症因子在其发病过程中起重要调节作用。本研究在于探讨IL-27对血管内皮细胞的直接作用。方法:采用ELISA方法,研究IL-27和TNF-α对人冠状动脉内皮细胞产生炎症相关细胞因子和趋化因子的作用。结果:IL-27显著增强TNF-α介导上调的炎症相关细胞因子IL-6和趋化因子CCL5的表达。IL-6和CCL5的表达受特异性信号分子抑制剂显著抑制。结论:人冠状动脉内皮细胞诱导释放IL-6和CCL5可能受JNK,p38MAPK和NF-κB通路差异调控。这些结果为阐明IL-27与TNF-α在动脉粥样硬化血管炎症发生中的作用提供重要生物化学基础。     

基于JNK通路研究老鹳草素对免疫性肝损伤小鼠的影响

为探讨老鹳草素对脂多糖(LPS)所致小鼠免疫性肝损伤的保护作用及可能机制,60只小鼠被随机分为正常组、模型组、水飞蓟素组(180 mg/kg)和老鹳草素低、中、高剂量组(50、100、200 mg/kg),小鼠腹腔注射10 mg/kg的LPS诱导免疫性肝损伤。采取HE染色观察小鼠肝细胞病理改变情况;生化法检测血清中谷丙转氨酶(ALT)、谷草转氨酶(AST)活性、碱性磷酸酶(ALP)、总胆红素(TBIL)水平,血清中超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性和丙二醛(MDA)含量;酶联免疫吸附试验(ELISA)法检测肝组织中炎症因子白介素-1β(IL-1β)、肿瘤坏死因子-α(TNF-α)和白介素-6(IL-6)的含量;蛋白免疫印迹实验(Western blot)法检测小鼠肝组织中p-ASK1、ASK1、MKK4、p-MKK4、JNK、p-JNK、c-Jun和p-c-Jun的表达水平。结果表明,老鹳草素各剂量组和水飞蓟素组小鼠肝组织炎症坏死和凋亡现象有不同程度的减轻。与模型组相比,老鹳草素各剂量组可显著降低血清中的ALT、AST、ALP、TBIL、MDA和肝组织中IL-1β、TNF-α和IL-6水平,上调血清中SOD和GSH-Px的水平,并且抑制肝组织中p-ASK1、p-MKK4、p-JNK、p-c-Jun的表达。综上所述,老鹳草素对LPS诱导的免疫性肝损伤具有保护作用,其机制可能与抑制JNK通路相关。     

3-Bromo-3-deazaneplanocin and 3-bromo-3-deazaaristeromycin: Synthesis and antiviral activity

As an outgrowth of our program to explore 3-deazaadenine carbocyclic nucleosides, 3-bromo-3-deazaneplanocin (5) and 3-bromo-3-deazaaristeromycin (6) have been synthesized from a readily available cyclopentenol and cyclopentanone and either 4-amino- or 4-chloro-1H-imidazo[4,5-c]pyridine (6-amino- or 6-chloro-3-deazaadenine) in 5 steps and 7 steps, respectively. Antiviral analysis found 5 to display significant activity towards a number of (-)-ssRNA and a few dsDNA viruses. Compound 6 was less active than 5 against selected examples of those viruses affected by 5.     

Cell density and amino acid transport in 3T3, SV3T3, and SV3T3 revertant cells

The transport of selected neutral and cationic amino acids has been studied in Balb/c 3T3, SV3T3, and SV3T3 revertant cell lines. After properly timed preincubations to control the size of internal amino acid pools, the activity of systems A, ASC, L, and Ly⁺ has been discriminated by measurements of amino acid uptake (initial entry rate) in the presence and absence of sodium and of transportspecific model substrates. L-Proline, 2-aminoisobutyric acid, and glycine were primarily taken up by system A; L-alanine and L-serine by system ASC; L-phenylalanine by system L; and L-lysine by system Ly⁺ in SV3T3 cells. L-Proline and L-serine were also preferential substrates of systems A and ASC, respectively, in 3T3 and SV3T3 revertant cells. Transport activity of the Na⁺-dependent systems A and ASC decreased markedly with the increase of cell density, whereas the activity of the Na⁺-independent systems L and Ly⁺remained substantially unchanged. The density-dependent change in activity of system A occurred through a mechanism affecting transport maximum (V_max) rather than substrate concentration for half-maximal velocity (K_m). Transport activity of systems A and ASC was severalfold higher in transformed SV3T3 cells than in 3T3 parental cells at all the culture densities that could be compared. In SV3T3 revertant cells, transport activity by these systems remained substantially similar to that observed in transformed SV3T3 cells. The results presented here add cell density as a regulatory factor of the activity of systems A and ASC, and show that this control mechanism of amino acid transport is maintained in SV40 virus-transformed 3T3 cells that have lost density-dependent inhibition of growth, as well as in SV3T3 revertant cells that have resumed it.     

Hyaluronate degradation in 3T3 and simian virus-transformed 3T3 cells

The cellular control of hyaluronate levels was examined in cultures of simian virus 40-transformed 3T3 (SV3T3) and 3T3 cells which are known to differ in their metabolism of hyaluronate. When [3H]hyaluronate was added to cultures of the two cell lines, four times more ligand was bound per mg of protein by the SV3T3 cells than by the 3T3 cells. Of the bound [3H] hyaluronate, 40% was degraded by the SV3T3 cells to oligosaccharides characteristic of the breakdown of hyaluronate, but only 2% was degraded by 3T3 cells. Hyaluronidase activity was found in the cell layer and medium of the SV3T3 cultures, but was not detectable in 3T3 cells. The SV3T3 enzyme was active only at acidic pH, but at neutral pH the secreted SV3T3 hyaluronidase was thermally more stable then the cell-associated enzyme. In contrast, both cell lines were found to contain similar amounts of beta-glucuronidase and beta-N-acetylglucosaminidase activity. We conclude that the elevated capacity of SV3T3 cells to degrade hyaluronate may be partially responsible for their lack of the hyaluronate-containing pericellular coat which is prominent around 3T3 cells.     

Calcium transport and exchange in mouse 3T3 and SV40-3T3 cells

The kinetics of Ca++ uptake have been evaluated in 3T3 and SV40-3T3 mouse cells. The data reveal at least two exchangeable cellular compartments in the 3T3 and SV40-3T3 cell over a 50-min exposure to 45Ca++. A rapidly exchanging compartment may represent surface-membrane-localized Ca++ whereas a more slowly exchanging compartment is presumably intracellular. The transition of the 3T3 cell from exponential growth (at 3 day's incubation) to quiescence (at 7 days) is characterized by a 7.5-fold increase in the size of the fast component. Quiescence of the 3T3 cell is also characterized by a 3.2-fold increase in the unidirectional Ca++ influx into the slowly exchanging compartment and a 3.6-fold increase in its size. The increase in size of the slow compartment at quiescence may result from a redistribution of intracellular Ca++ to a more readily exchangeable compartment, possibly reflecting a release of previously bound Ca++. In contrast, no significant change in any of these parameters is observed in the proliferatively active SV40-3T3 cells after corresponding period of incubation, even though these cells attained higher growth densities and underwent postconfluence.     

Synthesis and biological activity of 3 beta-fluorovitamin D3: comparison of the biological activity of 3 beta-fluorovitamin D3 and 3-deoxyvitamin D3

The alteration in the biologic activity of the vitamin D3 molecule resulting from the replacement of a hydrogen atom with a fluorine atom is a subject of fundamental interest. To investigate this problem we synthesized 3 beta-fluorovitamin D3 6 and its hydrogen analog, 3-deoxyvitamin D3 7, and tested the biologic activity of each by in vitro and in vivo methods. Contrary to previous reports which showed that 3 beta-fluorovitamin D3 was as active as vitamin D3 in vivo, we found that the fluoro-analog was less active than vitamin D3. With regard to stimulation of intestinal calcium transport and bone calcium mobilization in the D-deficient hypocalcemic rat, 3 beta-fluorovitamin D3 showed significantly greater biologic activity than its hydrogen analog, 3-deoxyvitamin D3. In the organ-cultured, embryonic chick duodenum, 3 beta-fluorovitamin D3 was approx 1/1000th as active as the native hormone, 1,25-dihydroxyvitamin D3, while 3-deoxyvitamin D3 was inactive even at microM concentrations, in the induction of the vitamin D-dependent, calcium-binding protein. With regard to in vitro activity in displacing radiolabeled 25-hydroxyvitamin D3 from vitamin D binding protein and radiolabelled 1,25-dihydroxyvitamin D3 from a chick intestinal cytosol receptor, 3 beta-fluorovitamin D3 and 3 beta-deoxyvitamin D3 both showed very poor binding efficiencies when compared with vitamin D3. Our results show that the substitution of a fluorine atom for a hydrogen atom at the C-3 position of the vitamin D3 molecule results in a fluorovitamin 6 with significantly more biological activity than its hydrogen analog, 3-deoxyvitamin D3 7.     

Protein degradation in 3T3 cells and tumorigenic transformed 3T3 cells

To study the relation of overall rates of protein degradation in the control of cell growth, we determined if transformation of fibroblasts to tumorigenicity affected their rates of degradation of short- and long-lived proteins. Rates of protein degradation were measured in nontumorigenic mouse Balb/c 3T3 fibroblasts, and in tumorigenic 3T3 cells transformed by different agents. Growing 3T3 cells, and cells transformed with Moloney sarcoma virus (MA-3T3) or Rous sarcoma virus (RS-3T3), degraded short- and long-lived proteins at similar rates. Simian virus 40 (SV-3T3)- and benzo(a)pyrene (BP-3T3)-transformed cells had slightly lower rates of degradation of both short- and long-lived proteins. Reducing the serum concentration in the culture medium from 10% to 0.5%, immediately caused about a twofold increase in the rate of degradation of long-lived proteins in 3T3 cells. Transformed lines increased their rates of degradation of long-lived proteins only by different amounts upon serum deprivation, but none of them to the same extent as did 3T3. Greater differences in the degradation rates of proteins were seen among the transformed cells than between 3T3 cells and some transformed cells. Thus, there was no consistent change in any rate of protein degradation in 3T3 cells due to transformation to tumorigenicity.