IL—6体外诱导成年大鼠骨髓破骨细胞形成的实验观察

目的：探讨IL－6对成年大鼠骨髓破骨细胞生成诱导的影响。方法：采用12周龄SD大鼠无菌条件下取出股骨，剪去两骺端，以α-MEM将骨髓细胞冲出，然后将细胞悬液接种于预置盖玻片或牙本质片的24孔培养板内，次日实验换含IL－6（10U/ml)的α-MEM培养液继培养2周，对照组培养液不含IL－6。：培养一周左右光镜下观察实验组可见明显单核细胞融合成多核细胞现象，多核细胞数量增多。经TRAP染色呈阳性反应，电镜下可观察到典型的破骨细胞骨吸收现象。结论：IL－6（10U/ml)可明显诱导成年大鼠骨髓破骨细胞的形成。     

白介素-6与1,25(OH)2维生素D3联合作用下大鼠骨髓破骨细胞的体外诱导培养

目的观察联合应用白介素(IL)-6和1,25(OH)2D3对大鼠骨髓破骨细胞生成诱导的影响.方法采用4周龄SD大鼠无菌条件下取出股骨,剪去两骺端,以α-MEM培养液将骨髓细胞冲出,然后将细胞悬液接种于预置盖玻片或牙本质片的24孔培养板内,24h后换液.试验分为4组,A组不加任何诱导因子;B组加入IL-6(10 U/ml);C组加入1,25(OH)2D3(1 ×10-8mol/L);D组加入IL-6(10 U/ml)和1,25(OH)2D3(1×10-8mol/L).每组各6孔,于培养的第7天进行多核细胞计数.结果培养1周左右IL-6与1,25(OH)2D3在体外均可单独诱导骨髓破骨细胞的形成,但D组多核细胞数与B、C组相比差异有显著性(P＜0.05).结论IL-6与1,25(OH)2D3联合作用下对骨髓破骨细胞生成的诱导效果明显高于单因素诱导效果.     

白介素-6与1,25(OH)_2维生素D_3联合作用下大鼠骨髓破骨细胞的体外诱导培养

目的观察联合应用白介素(IL)-6和1,25(OH)2D3对大鼠骨髓破骨细胞生成诱导的影响。方法采用4周龄SD大鼠无菌条件下取出股骨,剪去两骺端,以α-MEM培养液将骨髓细胞冲出,然后将细胞悬液接种于预置盖玻片或牙本质片的24孔培养板内,24 h后换液。试验分为4组,A组:不加任何诱导因子;B组:加入IL-6(10 U/ml);C组:加入1,25(OH)2D3(1×10-8mol/L);D组:加入IL-6(10 U/ml)和1,25(OH)2D3(1×10-8mol/L)。每组各6孔,于培养的第7天进行多核细胞计数。结果培养1周左右IL-6与1,25(OH)2D3在体外均可单独诱导骨髓破骨细胞的形成,但D组多核细胞数与B、C组相比差异有显著性(P<0.05)。结论IL-6与1,25(OH)2D3联合作用下对骨髓破骨细胞生成的诱导效果明显高于单因素诱导效果。     

白细胞介素-6对破骨细胞骨吸收效应及MMP-3表达影响的实验研究

目的：观察不同浓度IL－6对破骨细胞骨吸收的剂量效应及对破骨细胞基质金属蛋白酶－3表达的影响，以期进一步阐明IL－6介导基质金属蛋白酶在破骨细胞性骨吸收中的病理机制。方法：采用体外破骨细胞溶骨模型，通过原子吸收分光光度仪及免疫组化染色技术检测不同浓度IL－6对破骨细胞溶骨活性及其质金属蛋白酶－3表达的影响。结果：当IL－6＞10U／ml时，培养上清中Ca^2 浓度显著增加，牙本质片上骨吸收陷窝数目明显增多；当IL－6浓度为100U／ml、500U／ml时破骨细胞基质金属蛋白酶－3表达的阳性信号显著增强。结论：在IL－6作用下，破骨细胞表达基质金属蛋白酶－3。IL－6对破骨细胞具有激活作用，低浓度主要诱导破骨细胞形成，较高浓度刺激破骨细胞的溶骨活性。     

周期性牵张力对骨髓破骨细胞形成的影响

目的 :通过大鼠骨髓破骨细胞的体外诱导培养 ,观察不同时段周期性牵张力对骨髓破骨细胞形成的影响。方法 :通过体外细胞培养加载系统 ,选择频率为 6周 /min ,弹性基底膜发生 12 %形变率的周期性牵张力。试验共分为 4组 ,A组 :为对照组 ,在整个培养期间不加力 ;B组 :从培养的第 2d开始加力 ,连续加力 3d ;C组 :从培养的第 2d开始加力 ,连续加力 5d ;D组 :从培养的第 5d开始加力 ,连续加力 2d。每组各 6孔 ,均于培养的第 7d进行多核细胞计数。结果 :B组、C组多核细胞数量与对照组相比明显减少 (P <0 .0 5 ) ,而D组多核细胞数量与对照组相比无显著性差异 (P >0 .0 5 )。B组与C组相比亦无显著性差异。结论 :周期性牵张力主要是在骨髓诱导培养的早期抑制破骨细胞的形成 ,后期施力对破骨细胞的形成无明显影响。     

降钙素基因相关肽对体外大鼠破骨细胞形成的影响

目的 :了解降钙素基因相关肽 (CGRP)对体外培养大鼠破骨细胞形成的影响 ,探讨CGRP在局部骨改建中的作用机制。方法 :采用 1.2 5 (OH) 2 D3 体外诱导培养大鼠破骨细胞 ,观察不同浓度的CGRP对大鼠破骨细胞形成的影响。结果 :10 -9mmol/L、10 -8mmol/L、10 -7mmol/LCGRP不仅明显减少了TRAP阳性染色单核 /双核细胞的数量 ,同时也减少了多核细胞的数量 (P <0 .0 5 ) ,具有浓度依赖性。结论 :CGRP可能直接抑制破骨细胞的形成 ,在局部骨改建中发挥调节作用。     

破骨细胞分化因子诱导小鼠骨髓细胞形成破骨细胞的实验研究

目的:探讨破骨细胞分化因子(ODF)和巨噬细胞集落刺激因子(M-CSF)联合应用进行体外诱导小鼠骨髓细胞形成破骨细胞(OC)的能力。方法:收集5～6周小鼠骨髓细胞,在含M-CSF(10 ng/ml)的α-MEM全培养液中培养24h,然后将悬浮生长的细胞接种到24孔培养板,并加入不同浓度的ODF和M-CSF。,通过观察抗酒石酸盐酸性磷酸酶(TRAP)染色的阳性细胞和能否在骨磨片上形成吸收陷窝来鉴定OC形成情况。结果:在只加入ODF或M-CSF一种细胞因子时,未见有TRAP阳性或CTR阳性细胞形成,同时加入ODF和M-CSF,可形成典型的OC。TRAP阳性多核细胞的数目和培养液中钙离子浓度的增加与ODF的浓度呈正相关。结论:小鼠骨髓来源的单核细胞在ODF和M-CSF共同作用下可形成具有骨吸收功能的OC,为体外研究OC的分化发育和功能调节提供了一种新的方法。     

VEGF对兔骨髓细胞分化形成破骨细胞的诱导作用

目的:观察血管内皮生长因子(VEGF)对兔骨髓细胞分化为破骨细胞的诱导作用。方法:应用终未浓度为5 ng/mL的人重组rhVEGF体外诱导培养兔骨髓细胞,并与骨片共同培养,分别于诱导培养后3、6、9 d用抗酒石酸酸性磷酸酶(tartrate-resistant acid phosphatase,TRAP)染色进行破骨细胞鉴定计数和骨片吸收陷窝数目的统计。结果:诱导培养3 d,实验组与对照组的破骨细胞数和骨吸收陷窝数无显著性差异(P>0.05),而随着诱导培养时间延长,实验组两者的数量明显增加,在诱导培养6 d和9 d时,均明显高于对照组,差异有统计学意义(P<0.05)。结论:VEGF具有体外诱导骨髓细胞形成破骨细胞的作用。     

小鼠骨髓细胞和脾细胞诱导形成破骨细胞潜能的比较

目的在体外破骨细胞分化因子(RANKL)和巨噬细胞集落刺激因子(M-CSF)联合应用的情况下,比较小鼠骨髓细胞和脾细胞形成破骨细胞的能力。方法选用小鼠M-CSF依赖性非附着性骨髓细胞和脾细胞,以不同的细胞密度在含有25ng/mlsM-CSF和30ng/mlsRANKL的(-MEM培养液中培养5、9天后,计数形成的抗酒石酸酸性磷酸酶染色(TRAP)阳性多核细胞的数目和骨吸收面积。结果脾细胞形成的破骨样细胞与骨髓形成的细胞形态与功能均无明显差异,但所需的细胞密度为骨髓细胞的10~20倍。结论在特殊情况下,脾细胞可替代骨髓细胞进行体外破骨细胞实验,但培养条件应适当调整。     

周期性牵张力对骨髓破骨细胞MMP-3 mRNA表达的影响

目的 :研究周期性牵张力对成熟破骨细胞MMP 3mRNA表达的影响 ,探讨机械张力与破骨细胞骨基质作用的关系。方法 :实验组从骨髓破骨细胞体外诱导培养的第 7天施加 6周 /分 ,弹性基底膜发生 12 %形变率的周期性牵张力 ,2 4小时后 ,应用原位杂交染色技术检测多核破骨细胞内MMP 3mRNA表达变化情况。结果 :实验组从培养的第 7天施加 12 %平均形变率、6周 /分的周期性牵张力 ,2 4小时后多核破骨细胞MMP 3mRNA阳性信号在所观察视野内染色强度明显增强。结论 :MMP 3在骨组织应力改建过程中发挥着重要作用 ,体外周期性牵张力可刺激成熟破骨细胞MMP 3mRNA的表达。     

壳聚糖及其复合物对小鼠成骨细胞增殖及分化的影响

目的：用含壳聚糖(chitosan,CS)、Ⅰ型胶原蛋白和重组人骨形态发生蛋白2(recombinant human bone morphogenetic protein-2,rhBMP-2)的培养液体外培养成骨细胞MC3T3-E1,评价3种因素对成骨细胞增殖及分化的影响。方法：实验分为4组,实验组A：CSα-MEM培养基;实验组B：CS+Ⅰ型胶原蛋白溶液的α-MEM培养基;实验组C：CS +Ⅰ型胶原蛋白溶液+rhBMP-2溶液的α-MEM培养基。对照组为含1%FBS的α-MEM培养基。采用MTT法检测加入处理因素后1、3、5、7 d的吸光度(OD)值,并绘制细胞生长曲线,观察成骨细胞的增殖情况。采用碱性磷酸酶活性测定、碱性磷酸酶染色和茜素红钙结节染色观察成骨细胞的分化作用：检测加入处理因素后1、3、5、7 d的碱性磷酸酶活性,并在细胞培养的第7天进行碱性磷酸酶染色,第14天进行茜素红钙结节染色。采用SPSS13.0软件包对所得数据进行单因素方差分析,2组之间比较采用Post Hoc检验。结果：MTT检测结果显示,实验组C的OD值高于其他组,实验组C与其他组间的两两比较具有显著差异(P<0.05)。碱性磷酸酶活性测定结果显示,实验组C的活性高于其他组,实验组C与实验组A、对照组间两两比较具有显著差异(P<0.05),与实验组B两两比较无显著差异(P>0.05)。茜素红染色和碱性磷酸酶染色结果显示,实验组C可见更多的钙盐沉积,且蓝染颗粒多于其他组。结论：壳聚糖、Ⅰ型胶原蛋白和rhBMP-2共同作用,更能促进成骨细胞的增殖与分化。     

bFGF基因修饰的BMSCs促进大鼠下颌牵引成骨的研究

目的：探讨碱性成纤维生长因子（bFGF）基因修饰的自体骨髓间充质干细胞（BMSCs）促进大鼠下颌牵引成骨的作用。方法：36只雄性SD大鼠,随机分为实验组和对照组,同时对两组大鼠右下颌骨进行牵引成骨,牵引期最后1 d,实验组大鼠牵引间隙内注射转染重组质粒pcDNA-bFGF的BMSCs,对照组注射转染pcDNA空质粒的BMSCs。分别于固定期第2,4,8周分3批处死,并进行放射学检查、组织学检查及骨密度检测。结果：两组牵引间隙内均有新骨形成。各时间点实验组牵引间隙内新骨的形成和骨质密度均较对照组高（P〈0.05）。结论：bFGF基因修饰的BMSCs可有效促进DO新骨形成,为颌面部骨缺损的重建提供了一个新的修复方法。     

The effects of cold storage and endotoxin challenge on osteoblast viability and interleukin-6 production

Autogenous hip marrow is an excellent source of pluripotential cells for regenerative procedures. However, before this treatment modality can be employed a method to attenuate osteoclast activity must be developed. The shock of cold storage (4°C) is thought to abate osteoclast activity through the downregulation of osteolytic cytokines produced by osteoblasts. The objective of this study was to evaluate the effects of cold storage (4°C) and endotoxin challenge on bone cell culture viability and interleukin-6 (IL-6) production. These cells (osteoblasts) were primarily harvested from murine calvaria utilizing sequential digestions, separated by density gradient and combined. Twelve-well cell culture plates were inoculated with 2 × 10⁴ cells/ml and placed in cold storage for 1-14 d. After cold storage the cultures were then incubated at 37°C for 1-20 d. A set of replicate plates was also challenged with 10 ng/ml endotoxin upon incubation at 37°C for 4 consecutive days. Cells were evaluated daily for alkaline phosphatase activity. Cell culture supernatants were also collected daily and batch assayed for IL-6 production. Cell cultures did not survive more than 48 h of cold storage. There was a decrease in IL-6 secretion in all refrigerated cultures and a significant decrease in those cells refrigerated for 48 h versus control cultures (p < 0.05). Replicate cultures treated with endotoxin secreted significantly increased amounts of IL-6 in both the control cultures and the cultures exposed to 24 h of cold storage versus non-endotoxin-treated control cultures (p < 0.05). These observations suggest that after 48 h of cold storage autogenous marrow may be safe to use because of the dramatic decrease in IL-6 production by osteoblasts.     

Osseous reaction to implantation of two endodontic cements: Mineral trioxide aggregate (MTA) and calcium enriched mixture (CEM)

Aim: The aim of the present in vivo study was to determine bone tissue reaction to calcium enriched mixture (CEM) and mineral trioxide aggregate (MTA) using a rat femur model. Study Design: Sixty-three rats were selected and randomly divided into three groups of 21 each [experimental groups (n=15), control (n=6)]. Implantation cavities were prepared in each femoral bone and randomly filled with the biomaterials only in the experimental groups. The animals in three groups were sacrificed 1, 4, and 8 weeks postoperatively. Histologic evaluations comprising inflammation severity and new bone formation were blindly made on H&E-stained decalcified 6-μm sections. Results: At 1, 4, and 8 weeks after implantation number of inflammatory cells had decreased in the CEM, MTA and control groups, respectively, with no statistically significant differences. Conversely, new bone formation had increased in all the experimental and control groups, without statistically significant differences. Conclusion: The results suggest that biocompatibility of MTA, as gold standard, and CEM cement as a new endodontic biomaterial are comparable.     

表皮生长因子对牙囊细胞增殖活性的影响

目的：研究表皮生长因子（EGF）对体外培养的大鼠牙囊细胞增殖活性的影响。方法：原代培养Wistar大鼠牙囊细胞,选择生长良好的第3代细胞,分别加入不同浓度的EGF（0.5、1、5、10、50 ng/mL）与牙囊细胞共孵育5 d,MTT法对比观察不同浓度的EGF对牙囊细胞增殖活性的影响。数据采用SPSS 13.0软件包进行方差分析。结果：在EGF浓度为5～10 ng/mL时,牙囊细胞的增殖活性显著增高（P〈0.05）,10 ng/mL时达到最高（P〈0.01）。结论：EGF可作用于牙囊细胞,合适浓度的EGF能显著增加牙囊细胞的增殖活性。     

The influence of alendronate on bone formation and resorption in a rat ectopic bone development model

BACKGROUND: Most bone grafting techniques that include bone marrow, alloplastic materials, and extracellular bone matrix produce new bone mass, filling bone defects unpredictably. In most cases, the new bone undergoes resorption due to low local strains, resulting in significant bone loss. Recently, it was shown that alendronate and other bisphosphonates reduce bone loss when administered systemically or locally. The aim of this study was to investigate whether alendronate is effective on bone formation or bone resorption. METHODS: A total of 64 rats were divided into 2 main groups. In all the rats, fresh bone marrow removed from DA young rats was placed into demineralized rat femur cylinders (DBMC) and implanted into subcutaneous sites of host DA rats, to form new bone. Group A served as an alendronate treatment group, and group B served as a non-treated control. Group A received 100 microl of 1.5 mg/ml alendronate solution at 1, 2, and 3 weeks (group A1) and at 3, 4, and 5 weeks (group A2). At designated times, the rats were sacrificed, and the implanted DBMC was dissected out of the thorax and processed for histological and microradiography image analysis. RESULTS: Alendronate given at 1, 2, and 3 weeks (during the bone formation phase) did not increase the amount of bone or the visual bone density in comparison to the time-matched control, after 4 and 8 weeks. When alendronate was injected at 3, 4, and 5 weeks, the bone mass increased by 70% and by 166% after 6 and 10 weeks, respectively, in comparison to the untreated control. The visual bone density in group A2 was maintained at the level of 140 +/- 15 at 6 weeks and 152 +/- 15 at 10 weeks. The matched, non-treated control group B2 was significantly lower, 106 +/- 20 and 108 +/- 15, respectively. The histological sections showed that alendronate treatment at 3, 4, and 5 weeks maintained the normal appearance of the ossicle at 6 and 10 weeks in comparison to the osteopenic bone appearance in the matched controls. CONCLUSIONS: This study suggests that alendronate is effective in inhibiting bone loss, but ineffective during the bone formation phase. We suggest, therefore, that alendronate should be administered in procedures where bone resorption is expected.     

大鼠骨髓内皮细胞的分离培养及其形态特征

目的：分离培养大鼠骨髓内皮并进行生物学鉴定。方法：应用Peroll细胞分离介质（密度1．04－1．06g/ml)，将SD大鼠长骨骨髓经非连续梯度离心后收集位于中层的细胞进行培养，观察细胞生长状况，绘制细胞生长曲线并以透射电镜及Ⅷ因子免疫组化方法对培养细胞进行鉴定。结果：细胞圆型单层融合贴壁生长，平均直径15μm，单个核并位中央，群体倍增时间约为37h；Ⅷ因子免疫组化染色阳性；透射电镜显示细胞内具有特征性的W－P小体。结论：采用非连续梯度离心沉降法可获得高纯度的骨髓内皮细胞，该细胞具有与血管内皮细胞共同的特征。     

Angiotensin II induces interleukin-6 synthesis in osteoblasts through ERK1/2 pathway via AT1 receptor

Background

Interleukin-6 (IL-6) is a potent stimulator of osteoclastic bone resorption. Osteoblast secretion of IL-6 plays an important role in the regulation of bone metabolism. Angiotensin II (Ang II) has been shown to regulate the expression of potent inflammatory factors, including MCP-1 and IL-6, by stimulating endothelia cells, vascular smooth muscle cells (VSMC) and monocytes. However, of the mechanism by which Ang II regulates IL-6 expression in osteoblasts is unknown.

Aims

The present study was designed to investigate the effect of Ang II on IL-6 expression in osteoblasts isolated from mice. The receptor(s) required and the potential role of extracellular signal-regulated kinase 1/2 (ERK1/2) activation in Ang II-induced IL-6 synthesis was also examined in these cells.

Methods

The osteoblasts were isolated from the calvaria of mice and cultured in α-MEM medium. IL-6 mRNA expression and protein synthesis was determined by qPCR and ELISA analyses. ERK1/2 kinase activation was determined by western blot.

Results

The results indicate that Ang II induced IL-6 mRNA expression and protein synthesis in cultured osteoblasts. However, these effects were abolished by pre-treatment with Ang II type 1 (AT1) receptor antagonist, losartan, and the ERK1/2 inhibitor, U0126, inhibited Ang II-mediated IL-6 expression and the phosphorylation of ERK1/2.

Conclusion

Ang II induces the synthesis of IL-6 in osteoblasts through activation of the ERK1/2 pathway via the AT1 receptor.