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61.
62.
目的 揭示颗粒蛋白前体衍生物Atsttrin对骨关节炎的保护作用及对CD+4 T细胞的调节作用.方法 本研究起止时间为2018年10月至2019年12月,60只5周龄SD雄性大鼠购自西安交通大学医学部实验动物中心.采用膝关节前交叉韧带横断法建立骨关节炎大鼠模型,通过关节内注射15μL Atsttrin(1μg/μL)对模型大鼠进行治疗,每周注射1次,连续注射4周.通过番红O固绿染色检测软骨损伤程度,采用OARSI评分系统评价软骨退化情况.ELISA法检测大鼠血清干扰素-γ(IFN-γ)、白细胞介素-4(IL-4)、白细胞介素-17(IL-17)和转化生长因子-β(TGF-β)水平.流式细胞仪分析血清Th1、Th2、Th17和Treg细胞比例.应用终浓度为10μg/L的肿瘤坏死因子-α(TNF-α)诱导滑膜细胞和软骨细胞48 h,并分别用终浓度为10μg/L、20μg/L、50μg/L的Atsttrin处理滑膜细胞和软骨细胞48 h.通过5-溴-2-脱氧尿苷(BrdU)细胞增殖测定试剂盒检测滑膜或软骨细胞的增殖.通过RT-PCR和Western blotting检测软骨细胞中解聚蛋白样金属蛋白酶-4(ADAMTS-4)、基质金属蛋白酶-13(MMP-13)、IFN-γ、IL-4、IL-17和TGF-β的信使核糖核酸(mRNA)和蛋白表达.结果 与模型组相比,Atsttrin组大鼠的膝关节软骨破坏情况明显减轻(P<0.05).与模型组相比,Atsttrin组大鼠国际骨关节炎研究学会(OARSI)评分显著降低[(2.56±0.21)比(1.08±0.11),P=0.001].Atsttrin组大鼠的血清IFN-γ和IL-17水平显著低于模型组,而IL-4和TGF-β水平显著高于模型组(P<0.05).Atsttrin组大鼠的血清Th1和Th17细胞比例显著低于模型组,而Th2和Treg细胞比例显著高于模型组(P<0.05).Atst?trin处理显著降低了TNF-α诱导的滑膜细胞的增殖能力,并提高了TNF-α诱导的软骨细胞的增殖能力(P<0.05).Atsttrin显著下调了TNF-α诱导的软骨细胞中ADAMTS-4、MMP-13、IFN-γ和IL-17的mRNA和蛋白表达水平,并上调了IL-4和TGF-β的表达水平(P<0.05).结论 Atsttrin可有效抑制骨关节炎大鼠模型的软骨病变并提高关节功能.Atsttrin可通过抑制滑膜细胞增殖、促进软骨细胞增殖、抑制软骨机制降解来维持关节内微环境的稳定.此外,Atsttrin的关节软骨保护作用与纠正Th1/Th2细胞以及Th17/Treg细胞的失衡有关. 相似文献
63.
目的 为骺板组织工程寻找生物相容性良好的支架材料.方法 将体外培养的第三代骺板软骨细胞与可降解多孔丝素材料复合.应用扫描电镜、激光共聚焦显微镜、MTT等方法,对骺板软骨细胞与可降解多孔丝素材料的生物相容性进行观察.结果 骺板软骨细胞在可降解多孔丝素材料上生长良好,随着培养时间的延长,骺板软骨细胞逐渐增多.结论 可降解多孔丝素材料具有良好的生物相容性,可以作为骺板组织工程理想的支架材料.Abstract: Objective To assessfind the biocompatibility of scaffold SF for epiphyseal plate tissue engineering. Methods To culture the epiphyseal plate chondrocyte on scaffold SF. We studied biological characteristics of the cells by applying the ways of scanning electron- microscope, laser scan confocal microscope and MTT test. Results The epiphyseal plate chondrocyte grew well on scaffold SF. Conclusions The scaffold SF have good biocompatibility and can be used as ideal scaffold in epiphyseal plate tissue engineering. 相似文献
64.
培养状态下成人鼻中隔软骨细胞生物学特性的研究 总被引:3,自引:0,他引:3
目的:研究体外2的正常成人鼻中隔软骨细胞的生物学特性。方法:体外培养成我鼻中隔软骨细胞,观察原代及传代培养的形态学变化;测定细胞数量的变化及其生长曲线,观察细胞的增殖;借助特殊染色、免疫组织化学的方法了解糖胺聚糖、碱性磷酸酶、Ⅱ型胶原的合成情况,测定冷冻复苏后的细胞存活。结果:初始接种细胞为圆形,细胞贴壁后4d细胞逐渐变为放射延异状;从第5代开始绝大部分细胞转变成纤维样细胞。2代细胞体外培养至第5 相似文献
65.
Laurent Bédouet Florentina Pascale Michel Bonneau Michel Wassef Alexandre Laurent 《Toxicology in vitro》2011,25(8):1944-1952
Intra-articular drug delivery systems (DDSs) are envisaged as interesting alternative to locally release nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen to reduce pain in patients with osteoarthritis. The present study examines the toxicity of (S)-ibuprofen on chondrocytes and synoviocytes isolated from sheep shoulder joint and cultured in monolayers during 72 h, and on joint explants (cartilage and capsule) cultured in mono- or in co-culture for 13 days. (S)-ibuprofen (5 μM up to 1 mM) did not reduce the cell viability and protein content when added on chondrocyte monolayers, while at 1 mM (S)-ibuprofen reduced (by 8%, p = 0.01) the synoviocytes viability compared to untreated cells. During co-culture of joint explants, (S)-ibuprofen at 50 μM significantly reduced by 35% the spontaneous release of glycosaminoglycans (GAGs) from cartilage (p = 0.0065) whereas in monoculture, (S)-ibuprofen was inactive on GAG metabolism. (S)-ibuprofen at 1 mM significantly reduced cell lysis (lactate dehydrogenase leakage) by 74% during monoculture of capsule explants (p = 0.0136) and by 35% during co-culture of explants (p = 0.0013). Our findings demonstrate that the active isomer of ibuprofen at micro- and millimolar levels was not toxic for chondrocytes and synoviocytes and may reduce at 1 mM the cell lysis during culture of joint explants. The limited toxicity of (S)-ibuprofen at low and high concentration in sheep joint shoulder makes this enantiomer a promising drug candidate for the loading of intra-articular DDS. 相似文献
66.
Osteoarthritic cartilage fibrillation is associated with a decrease in chrondrocyte adhesion to fibronectin 总被引:3,自引:0,他引:3
Muriel Piperno Pascal Reboul Marie-Pierre Hellio Le Graverand M.J. Peschard Marliese Annefeld M. Richard Eric Vignon 《Osteoarthritis and cartilage / OARS, Osteoarthritis Research Society》1998,6(6):393-399
OBJECTIVE: Cartilage destruction in osteoarthritis (OA) is generally accepted as a failed repair process. Cell adhesion is implicated in tissue repair. Therefore, adhesion of OA chondrocytes to extracellular matrix proteins was investigated. DESIGN: Using chondrocytes from human OA femoral head cartilage, adhesion to fibronectin and type II collagen of cells from distinct areas showing an intact cartilage surface or a fibrillated cartilage surface was studied. Modulation of chondrocyte adhesion by both protein kinase C (PKC) inhibitors and glucosamine sulfate (GS) was also investigated. RESULTS: A significant (P < 0.05) decrease in adhesion to fibronectin of chondrocytes from fibrillated cartilage, relative to those from grossly normal OA cartilage, was demonstrated. Adhesion to type II collagen was not modified by the chondrocyte origins (either from normal or fibrillated OA cartilage). Adhesion to fibronectin of cells from grossly intact cartilage was decreased by the addition of PKC and calmodulin-dependent kinase inhibitors, W7 and sphingosine, to the cell culture. Adhesion to fibronectin of chondrocytes from fibrillated cartilage was significantly (P < 0.05) increased after glucosamine sulfate treatment. CONCLUSION: Fibrillation of cartilage from OA femoral head is associated with a defective adhesion of chondrocytes to fibronectin. The process is suggested to be dependent of PKC and/or calmodulin-dependent kinases and potentially reversible. Conceivably, it could play a role in OA cartilage destruction. 相似文献
67.
S-100 protein immunostaining identifies cells expressing a chondrocytic phenotype during articular cartilage repair. 总被引:3,自引:0,他引:3
The healing of articular surface defects has been studied with conventional histology, which relies on the staining of the extracellular matrix to identify the phenotype of the cells present. A chondrospecific cellular marker would be useful. S-100 protein has been found in all chondroid tissues studied, and we evaluated its usefulness in the study of articular cartilage repair. Full-thickness rabbit femoral condylar defects were made, and the specimens were studied at serial time intervals. S-100 protein staining positively showed chondroid cells in the 7- and 14-day specimens, which were not identifiable by conventional techniques. At 30 and 60 days, an S-100 positive band of cells separated a deep safranin-O positive hypertrophic layer from a fibrocellular surface layer. At 120 days, the presence of S-100 protein identified cells with chondrogenic potential, and the lack of S-100 protein in other cells embedded in conventionally stained matrix suggested that these cells were no longer of a chondroid phenotype. The presence of S-100 protein-identified chondroid cells early in the repair process when the cells had not begun to synthesize conventionally stainable matrix and the lack of S-100 protein in cells late in the repair positively identified a phenotypic change earlier than conventional histology. 相似文献
68.
H R Leipold N Burton-Wurster J Steinmeyer M S Vernier-Singer G Lust 《Journal of orthopaedic research》1992,10(1):33-48
The ability of cyclic adenosine monophosphate (cAMP) to maintain differentiated properties of canine articular chondrocytes in culture is reported. Treatment with 0.5 mM dibutyryl cAMP (DBcAMP) caused the cells to adopt a more rounded morphology. This change in morphology seems to have no effect on the overall biosynthetic rates of the cells. After a pulse with 35S-methionine, there was no difference in the concentration of labeled proteins between cultures treated with DBcAMP and control cultures. After 6 days, the amount of fibronectin (FN) in the media of DBcAMP-treated cultures detected by an enzyme-linked immunosorbent assay was specifically reduced by 30%. The amount of 35S-FN purified by gelatin-affinity chromatography decreased 33%. Moreover, the percentage of FN containing the extra domain A sequence was reduced from 19.4 +/- 8.7% in control cultures to 9.6 +/- 4.2%. Concomitant with the decrease in FN, there was an increase in the concentration of keratan sulfate in the media of DBcAMP-treated cultures. After 6 days, treated cultures had 47% more keratan sulfate than controls did. These changes appear not to be the result of a change in the deposition of FN or keratan sulfate, because the amount of these molecules that could be extracted from the cell layer was typically below the limit of detection of the assays. Instead, it seems there is a phenotypic change in the chondrocytes pertaining to the production of FN and keratan sulfate. 相似文献
69.
目的评价羧甲基壳聚糖对重组人白细胞介素(rhIL)-1β刺激下软骨细胞凋亡的影响,并探讨其作用机制。方法体外培养兔软骨细胞,加入不同浓度羧甲基壳聚糖预处理1h后,加入rhIL-1β共培养24h,通过Annexin V-FITC和PI双标及Hoechst 33342荧光染色检测软骨细胞凋亡;以罗丹明-123荧光染色检测线粒体膜电位和荧光素酶反应检测线粒体合成ATP能力来评价线粒体功能。结果羧甲基壳聚糖能明显抑制IL-1β诱导的软骨细胞凋亡,呈剂量依赖性;羧甲基壳聚糖可恢复IL-1β对软骨细胞线粒体功能的损害。结论羧甲基壳聚糖通过保护线粒体功能抑制IL-1β诱导的软骨细胞凋亡。 相似文献
70.
目的观察过氧化物酶Ⅰ(PrxⅠ)在正常和骨关节炎(OA)膝关节软骨组织中的表达和分布特点,探讨PrxⅠ与活性氧歧化物和凋亡等在OA软骨表层聚集现象之间的关联。方法分别从正常膝关节提取正常软骨(NC,n=21)和接受膝关节表面置换术的OA患者提取OA软骨(OA,n=21),应用Westernblot技术检测PrxⅠ在正常软骨细胞和OA软骨细胞中表达水平的总体差异,并用免疫组织化学技术观察PrxⅠ蛋白在正常与OA软骨表/中/深各层组织表达和分布的特点。结果 Western blot证实PrxⅠ在OA软骨组织中的表达水平较正常软骨组织显著提高2.89倍(t=18.34,P〈0.01)。免疫组织化学显示PrxⅠ在正常软骨组织的表层、中层和深层呈现较均一的表达,但是,在OA软骨组织中,PrxⅠ的表达水平存在显著层间差异。PrxⅠ在软骨组织深层表达水平显著升高,但在浅层细胞中,PrxI的表达水平反而显著减低甚至缺如。结论虽然总体表达水平升高,但PrxⅠ在OA软骨组织表层的表达缺如,可能与OA软骨组织表层活性氧歧化物蓄积和细胞凋亡聚集现象相关。 相似文献