脱细胞随机肌腱支架促进骨髓间充质干细胞骨向分化

目的:探究随机肌腱细胞外基质(ECM)支架对骨髓间充质干细胞(BMSCs)活力和分化的影响。方法:从Sprague-Dawley大鼠股骨和胫骨中提取BMSCs,体外培养,观察细胞形态,并利用流式细胞术鉴定细胞干性。采用1%Triton X-100和DNase/RNase混合液对鼠尾肌腱进行脱细胞处理,利用HE染色和DNA含量测定考察肌腱组织中细胞核残余情况。制备胶原纤维随机排列的肌腱ECM支架,培养BMSCs,以孔板中生长的细胞为对照组,利用Live/Dead染色和CCK8法考察细胞的活力和形态;利用RT-qPCR检测肌腱标志物I型胶原蛋白(Col I)、肌腱特异转录因子scleraxis(SCX)及成骨标志物碱性磷酸酶(ALP)和Runt相关转录因子2(RUNX2)的表达水平。结果:HE染色结果显示,经过脱细胞处理后肌腱组织内无细胞残余,且DNA含量从(481.7±15.8)μg/g显著性降至(31.0±3.8)μg/g(P<0.05),脱细胞处理成功。7 d时,种植在支架上的BMSCs的活力较对照组显著增强(P<0.05);14 d时,种植在支架上的BMSCs肌腱标志物Col I和SCX的表达量较对照组显著下调,而成骨标志物ALP和RUNX2的表达量较对照组显著上调(P<0.05)。结论:脱细胞随机肌腱ECM支架能增强BMSCs活力,并诱导其向成骨细胞分化。     

雌激素剂量依赖性促进小鼠骨髓间充质干细胞的成骨分化

背景：绝经后骨质疏松的发病与雌激素水平的下降关系密切。 目的：观察不同浓度雌激素对小鼠骨髓间充质干细胞成骨分化能力的影响,及其与微小RNA-26a的关系。 方法：取小鼠股骨与胫骨骨髓,全骨髓贴壁法获得并纯化骨髓间充质干细胞,分别以0,10-10,10-9,10-8,10-7,10-6 mol/L的雌二醇对其成骨诱导过程进行干预。 结果与结论：雌二醇对骨髓间充质干细胞的增殖能力影响不明显,但可明显提高其成骨能力;同时雌二醇可促进骨髓间充质干细胞成骨基因RUNX2,OCN mRNA及RUNX2,SP7蛋白的表达,以10-9 mol/L雌二醇的作用最明显,但10-9 mol/L雌二醇促进微小RNA-26a mRNA表达的能力最弱。说明雌二醇可剂量依赖性促进骨髓间充质干细胞的成骨分化,微小RNA-26a可能在此过程中发挥作用。关键词：微小RNA-26a;雌激素;骨髓间充质干细胞;成骨分化;小鼠 doi:10.3969/j.issn.1673-8225.2012.19.003     

循环轴向压缩应力增强基质依赖型组织工程骨骨再生能力的研究

目的 研究循环轴向压缩应力（CACS）对基质依赖型组织工程骨（M-TEB）骨再生能力的影响。方法 首先,在构建静态M-TEB过程中加载CACS,得到动态M-TEB;然后,对各组M-TEB进行表征,并构建动物模型来评价其骨再生能力;最后,通过转录组测序探究CACS对骨髓间充质干细胞（BMSCs）基因表达的影响,并研究M-TEB来源条件培养基对内皮祖细胞（EPCs）迁移、增殖和对BMSCs成骨分化的影响。结果 ①动态M-TEB组在骨缺损区有更多新骨生成,且骨体积分数和骨密度均显著优于假手术组和静态M-TEB组（P均＜0.01）;②前30个有显著差异（q＜0.01）的基因本体论（GO）术语主要涉及MAPK通路、细胞凋亡和血管生成等,且差异基因VEGFA在这些GO术语中出现频次最高（28次）;③相比静态M-TEB来源条件培养基,动态M-TEB来源条件培养基具有更强的促进EPCs迁移、增殖和BMSCs成骨分化的作用（P均＜0.05）, 阻断实验证实VEGFA在其中发挥重要功能。结论 CACS促进BMSCs表达和分泌VEGFA,提高动态M-TEB中VEGFA浓度,最终增强其在大鼠股骨缺损模型中的骨再生能力。     

膜联蛋白A1在兔骨髓间充质干细胞体外诱导成骨和成脂早期的表达

背景：骨髓间充质干细胞分化过程中膜联蛋白A1表达变化的研究报道各有不同看法。 目的：分析兔骨髓间充质干细胞在体外诱导成骨和成脂过程中膜联蛋白 A1基因的表达变化。 方法：应用全骨髓贴壁法分离培养骨髓间充质干细胞,分别加入含成骨诱导剂、成脂诱导剂及不添加任何诱导剂的培养基进行培养。 结果与结论：膜联蛋白A1基因在成骨诱导过程中与未诱导细胞相比有明显下调趋势,差异有显著性意义(P < 0.01),而在成脂诱导剂中则为上升(P < 0.01)。成骨诱导剂对细胞生长存在抑制作用并增加细胞凋亡(P < 0.01),而成脂诱导剂对细胞生长与凋亡作用较小(P > 0.05)。因此排除了诱导剂对细胞的作用之后,推测膜联蛋白A1基因可能与骨髓间充质干细胞体外向脂肪细胞分化存在一定关系,但尚不能肯定其在成骨分化中的作用。     

Periostin promotes migration,proliferation, and differentiation of human periodontal ligament mesenchymal stem cells

Overview: Periostin (POSTN) is critical to bone and dental tissue morphogenesis, postnatal development, and maintenance; however, its roles in tissue repair and regeneration mediated by human periodontal ligament mesenchymal stem cells (PDLSCs) remain unclear. The present study was designed to evaluate the effects of POSTN on hPDLSCs in vitro. Materials and Methods: hPDLSCs were isolated and characterized by their expression of the cell surface markers CD44, CD90, CD105, CD34, and CD45. Next, 100 ng/mL recombinant human POSTN protein (rhPOSTN) was used to stimulate the hPDLSCs. Lentiviral POSTN shRNA was used to knockdown POSTN. The cell counting kit-8 (CCK8) and scratch assay were used to analyze cell proliferation and migration, respectively. Osteogenic differentiation was investigated using an alkaline phosphatase (ALP) activity assay, alizarin staining, and quantitative calcium analysis and related genes/protein expression assays. Results: Isolated hPDLSCs were positive for CD44, CD90, and CD105 and negative for CD34 and CD45. In addition, 100 ng/mL rhPOSTN significantly accelerated scratch closure, and POSTN-knockdown cells presented slower closure at 24 h and 48 h. Furthermore, the integrin inhibitor Cilengitide depressed the scratch closure that was enhanced by POSTN at 24 h. The CCK8 assay showed that 100 ng/mL rhPOSTN promoted hPDLSC proliferation. Moreover, 100 ng/mL rhPOSTN increased the expression of RUNX2, OSX, OPN, OCN, and VEGF and enhanced ALP activity and mineralization. POSTN silencing decreased the expression of RUNX2, OSX, OPN, OCN, and VEGF and inhibited ALP activity and mineralization. Conclusions: POSTN accelerated the migration, proliferation, and osteogenic differentiation of hPDLSCs.     

振动应力刺激骨髓间充质干细胞修复兔骨缺损

背景：研究证实,力学因素可调控、诱导骨髓间充质干细胞定向分化为骨细胞,提高分化效率。 目的：观察振动应力刺激对兔骨缺损微环境中骨髓间充质干细胞移植修复肱骨骨缺损成骨分化能力的影响。 方法：24只兔按随机数字表法分为非振动单纯骨基质明胶组、非振动骨基质明胶+骨髓间充质干细胞复合植入组、振动骨基质明胶+骨髓间充质干细胞复合植入组,每组8只,建立兔肱骨骨缺损模型。振动组兔置于振动平台,以0.3 G的加速度,25 Hz,正弦波型,1次/d,30 min/次,持续4周施加振动刺激。 结果与结论：造模4周后,大体观察结果显示,振动组骨痂生长良好,组织学切片显示其新生骨量较多,可见大量成骨细胞,骨缺损与断端形成骨性连接;振动组Ⅰ型胶原蛋白、RUNX2 mRNA表达水平明显高于非振动组。提示振动应力刺激可促进骨缺损微环境中骨髓间充质干细胞的成骨分化能力,提高Ⅰ型胶原蛋白、RUNX2 mRNA表达水平,从而加速骨缺损修复的进程。     

M2型巨噬细胞外泌体诱导骨髓间充质干细胞的成骨分化北大核心

背景:目前研究表明,M2型巨噬细胞能够促进成骨分化并呈网络状调控,外泌体可携带大量信息参与细胞间的信号传导,M2型巨噬细胞来源外泌体是否能促进骨髓间充质干细胞的成骨分化,有待研究。目的:探究M2型巨噬细胞来源外泌体对骨髓间充质干细胞成骨分化的影响。方法:培养鼠源性巨噬细胞系RAW264.7与鼠骨髓间充质细胞系CP-M131,培养至第3代,应用白细胞介素4诱导巨噬细胞极化为M2型巨噬细胞,从M2型巨噬细胞培养上清中提取外泌体,然后用终质量浓度为0,30,60,90 mg/L的外泌体与骨髓间充质干细胞共培养72 h后收集样本,以及60 mg/L M2型巨噬细胞来源外泌体与骨髓间充质干细胞共培养24,48,72 h后收集样本,Western blot检测骨髓间充质干细胞中成骨相关因子RUNX2和碱性磷酸酶蛋白表达,茜素红染色检测矿物质沉积情况。结果与结论:①成骨相关因子RUNX2及碱性磷酸酶的表达水平与巨噬细胞外泌体质量浓度密切相关,与空白对照组比较,60 mg/L外泌体组RUNX2、碱性磷酸酶表达明显升高(P<0.05),干预72 h RUNX2、碱性磷酸酶表达明显升高(P<0.05);②茜素红实验结果表明,与空白对照组比较,60 mg/L外泌体组钙结节含量较高(P<0.05),干预72 h钙结节含量较高(P<0.05);③结果表明,M2型巨噬细胞分泌的外泌体能够诱导骨髓间充质干细胞向成骨细胞分化。     

A comparative analysis of the osteogenic capacity of osteoblasts from newborn and two-week-old rats

AimTo compare the proliferation and osteogenic differentiation of osteoblasts between newborn rats (1d group) and two-week-old rats (14d group) and to clarify the mechanism underlying these effects.MethodThe endogenous expression of osteogenic marker genes was detected by qPCR, including ALP, OCN, Col1a1, and Runx2. The osteoblasts proliferation was evaluated by EdU assay and Western Blotting [PCNA and Cyclin D1]. ALP activities in osteoblasts were detected using a PNPP kit, ALP staining and qPCR. Mineralized nodule formation and intracellular calcium levels were assessed by Alizarin Red staining and calcium colorimetric assay respectively while OCN, Col1a1 and Runx2 levels in osteoblasts were analyzed by immunostaining. Osteogenesis-associated pathways including Wnt/β-Catenin, Akt/PPAR and Smad were analyzed via Western Blotting.ResultEndogenous ALP, OCN, Col1a1, and Runx2 expression levels were significantly higher in osteoblasts from 14d group than those from 1d group. After treatment with osteogenic induction medium, osteoblast proliferation, ALP activity, mineralized nodule formation, and intracellular calcium levels were markedly increased in osteoblasts from 1d group, with similar results also being observed for the expression of OCN, Col1a1, and Runx2. Wnt3a, β-catenin, p-Akt, p-Smad1/5/8, and p-Smad5 protein levels were also higher in osteoblasts from 1d group relative to those from 14d group, while the expression of PPARγ was lower.ConclusionThe superior osteogenic differentiation capacity in osteoblasts was associated with the higher activation levels of Wnt/β-Catenin, Akt/PPAR and Smad signaling pathways, and the enhanced proliferative activity in osteoblasts from 1d group.     

Klotho对大鼠骨髓间充质干细胞增殖和分化的影响

目的 探讨延缓衰老基因Klotho对骨髓间充质干细胞（BMSCs）增殖和分化的影响。 方法 体外条件下培养大鼠骨髓间充质干细胞,构建分泌型Klotho(sKL)过表达的BMSCs。Western blotting检测细胞及培养基中sKL的表达;MTT法检测细胞增殖能力;Western blotting检测衰老标志物P53、P21蛋白的表达。利用成骨诱导液定向诱导BMSCs向成骨细胞分化,应用碱性磷酸酶(ALP)染色鉴定成骨效果;利用成脂诱导液定向诱导BMSCs向脂肪细胞分化,应用油红O染色鉴定成脂效果。 结果 Western blotting结果显示,sKL组细胞和培养基中sKL蛋白表达显著上调（P<0.05）,P53、P21表达显著下调（P<0.05）;MTT结果显示,各组细胞吸光度值（A值）差别无显著性（P>0.05）,sKL组成骨及成脂能力明显强于对照组（P<0.05）。 结论 sKL增强了大鼠BMSCs的延缓衰老能力,对BMSCs的成骨分化和成脂分化产生一定的促进作用,而对BMSCs的增殖无显著影响。     

大鼠骨髓间充质干细胞成骨分化过程中Hedgehog信号分子的表达

背景：Hedgehog信号通路是一个在胚胎阶段调控多种组织器官发育的重要信号通路,在成骨发育方面具有重要的作用。但Hedgehog信号分子在大鼠骨髓间充质干细胞体外诱导分化为成骨细胞过程中的作用尚未清楚。 目的：体外诱导大鼠骨髓间充质干细胞向成骨分化,检测Hedgehog信号分子在成骨诱导分化过程中的变化。 方法：从大鼠骨髓中分离得到骨髓间充质干细胞,进行地塞米松成骨诱导,通过免疫组化方法鉴定成骨的情况,Western Blot方法检测 Hedgehog信号分子SHH和IHH在骨髓间充质干细胞成骨分化过程中的表达。 结果与结论：成功分离得到骨髓间充质干细胞,地塞米松诱导培养7,14,21 d 后,Ⅰ型胶原的表达量逐渐增加;在诱导成骨分化过程中,SHH蛋白表达升高,诱导组的表达明显高于未诱导组的表达(P < 0.05),而IHH蛋白的表达降低,诱导组的表达明显低于未诱导组的表达(P < 0.05)。结果提示,Hedgehog信号分子参与地塞米松诱导骨髓间充质干细胞分化为成骨细胞的过程,且SHH和IHH在间充质干细胞诱导成骨过程中的作用有差异。     

大鼠骨髓间充质干细胞成骨诱导分化的超微结构变化

背景：目前对骨髓间充质干细胞成骨诱导分化的超微结构观察的报道甚少。 目的：采用全骨髓贴壁法分离培养大鼠骨髓间充质干细胞,成骨诱导并染色鉴定,利用电镜观察诱导前后细胞超微结构变化特点。 方法：全骨髓贴壁法体外分离、培养、纯化大鼠骨髓间充质干细胞,流式细胞仪检测细胞表面标记物,成骨染色鉴定向成骨方向诱导分化,扫描电镜及透射电镜观察成骨诱导前后细胞超微结构变化。 结果与结论：培养的第3代骨髓间充质干细胞纯度高、活力强,成骨诱导后的碱性磷酸酶活性染色、钙化结节染色均呈阳性。扫描电镜及透射电镜观察显示,经向成骨细胞诱导分化后,细胞形态铺展,不规则,其线粒体、粗面内质网、空泡明显增多,表明细胞功能活跃。     

Role of the ERK1/2 Signaling Pathway in Osteogenesis of Rat Tendon-Derived Stem Cells in Normoxic and Hypoxic Cultures

Background: Ectopic ossification and increased vascularization are two common phenomena in the chronic tendinopathic tendon. The increased vascularization usually leads to an elevated local oxygen tension which is one of micro-environments that can influence differentiate status of stem cells.Objective: This study aimed to investigate the osteogenesis capacity of rat tendon-derived stem cells TDSCs (rTDSCs) in normoxic and hypoxic cultures, and to study the role of ERK1/2 signaling pathway in this process.Methods: rTDSCs were subjected to osteogenesis inductive culture in hypoxic (3% O₂) and normoxic (20% O₂) conditions. The inhibitor U0126 was added along with culture medium to determine the role of ERK1/2 signaling pathway. Cell viability, cell proliferation, alizarin red staining, alkaline phosphatase (AKP) activity, gene expression (ALP, osteocalcin, collagen I and RUNX2) and protein expression (p-ERK1/2 and RUNX2) of osteogenic-cultured rTSDCs were analyzed in this study.Results: Hypoxic and normoxic culture had no effects on cell viability of rTDSCs, whereas the proliferation potential of rTDSCs was significantly increased in hypoxic culture. The osteogenesis capacity of rTDSCs in normoxic culture was significantly promoted compared with hypoxic culture, which was reflected by an increased alizarin red staining intensity, an elevated ALP activity, and the up-regulated gene (ALP, osteocalcin, collagen I and RUNX2) or protein (RUNX2) expression of osteogenic makers. However, the osteogenesis capacity of rTDSCs in both hypoxic and normoxic cultures was attenuated by the inhibitor U0126.Conclusion: Normoxic culture promotes osteogenic differentiation of rTDSCs compared with the hypoxic culture, and the ERK1/2 signaling pathway is involved in this process.     

Expression of SP7/osterix and alkaline phosphatase in bone marrow mesenchymal stem cells with Cbfal/RUNX2 gene silencing regulated by the water extracts from Bushen huoxue decoction北大核心

BACKGROUND: Bushen Huoxue Decoction (BSHXD) can promote osteogenesis of bone marrow mesenchymal stem cells (BMSCs) in vitro. Exploring the molecular mechanisms involved is of clinical benefits. OBJECTIVE: To discuss the changes in the expression of SP7/Osterix and alkaline phosphatase (ALP) in BMSCs with Cbfal/RUNX2 gene silencing regulated by the water extracts from BSHXD. METHODS: BMSCs were isolated and cultured by the bone marrow adherent method, and BMSCs at passage 3 were used in the assay. BMSCs were transfected with nothing (blank control group), Cbfal/RUNX2 gene silencing lentivirus (silencing group), and negative viral vector (negative control group), respectively. Then, the cells were cultured in 100 mg/L BSHXD water extract, and 3 days later, the protein and mRNA expression of RUNX2 and Osterix was detected by western blot and qPCR, respectively. Activity of ALP in the BMSCs was also detected in each group. RESULTS AND CONCLUSION: The transfection efficiency of Cbfal/RUNX2 gene silencing lentivirus was about 90%. The protein and mRNA expressions of RUNX2 and Osterix were significantly decreased in the BMSCs transfected with Cbfal/RUNX2 gene silencing lentivirus as compared with the other two groups, and so was the ALP activity (P < 0.01). After treated with the water extracts from BSHXD, the expression of RUNX2 and Osterix as well as the ALP activity in the BMSCs transfected with Cbfal/RUNX2 gene silencing lentivirus increased significantly (P < 0.01). To conclude, the water extract from the BXHXD can up-regulate the expression of RUNX2 and Osterix and the activity of ALP, thus promoting BMSCs osteogenic differentiation. © 2018, Journal of Clinical Rehabilitative Tissue Engineering Research. All rights reserved.     

BMP-4 increases activin A gene expression during osteogenic differentiation of mouse embryonic stem cells

Abstract

Activin A is a growth factor released by mature osteoblasts that has a critical effect on bone formation. We investigated the effect of bone morphogenetic protein (BMP)-4 on activin A gene expression during in vitro osteogenic differentiation of mouse embryonic stem (ES) cells. Embryoid bodies were cultured in retinoic acid (RA) for three days and then without RA for two days. Seeded cells received osteogenic medium with β-glycerophosphate, L-ascorbic acid 2-phosphate and dexamethasone during 19 days, with or without BMP-4. Six independent experiments were carried out. Real-time PCR was used to detect gene expression of activin A, Oct-4, Nanog, osteocalcin, RUNX2 and bone alkaline phosphatase. Immunofluorescence was used to co-localize activin A with the undifferentiation marker stage-specific embryonic antigen 1. Cells treated with BMP-4 had an increased gene expression of activin A, osteocalcin and bone alkaline phosphatase (p?<?0.05). In conclusion, BMP-4 increases activin A gene expression during mouse ES cell differentiation into bone precursors.     

3种组织来源的间充质干细胞体外成骨能力的比较

目的比较成人骨髓间充质干细胞(BMSCs)、人脐带间充质干细胞(UC-MSCs)和人胎盘间充质干细胞(P-MSCs)的成骨能力。方法用含10%胎牛血清的DMEM/Ham's F-12培养液培养3种MSCs,CCK8法检测增殖能力,流式细胞仪鉴定3种细胞。碱性磷酸酶(ALP)和茜素红染色观察细胞经成骨诱导后成骨分化蛋白-ALP的分泌和矿化钙结节的沉积。实时荧光定量PCR(RT-q PCR)法检测MSCs骨再生相关基因的表达。Western blot方法检测MSCs成骨再生相关基因的蛋白表达。结果 MSCs在第3天进入对数增殖期。3种细胞的表面标志物阳性率:CD44、CD90和CD105均高于98%。3种MSCs成骨诱导9 d时,3种MSCs的实验组均表达大量成骨分化蛋白-ALP,成骨诱导18 d时3种MSCs均呈现较好的矿化能力;3种MSCs成骨诱导9 d时,实验组RUNX2和ALP基因显著性高表达(P0.05),成骨诱导18 d时,实验组RUNX2和骨钙素(OCN)亦显著性高表达(P0.05);3种MSCs成骨诱导9 d时,实验组均检测到RUNX2和ALP的蛋白表达;成骨诱导18 d时,实验组细胞亦检测到RUNX2和OCN的蛋白表达。结论 UC-MSCs和P-MSCs具有良好的成骨分化能力,有望作为骨组织工程的种子细胞用于治疗骨缺损。     

Enhanced osteogenesis and angiogenesis by PCL/chitosan/Sr-doped calcium phosphate electrospun nanocomposite membrane for guided bone regeneration

Abstract

Membranes play pivotal role in guided bone regeneration (GBR) technique for reconstruction alveolar bone. GBR membrane that is able to stimulate both osteogenic and angiogenic differentiation of cells may be more effective in clinic practice. Herein, we fabricated the Sr-doped calcium phosphate/polycaprolactone/chitosan (Sr-CaP/PCL/CS) nanohybrid fibrous membrane by incorporating 20?wt% bioactive Sr-CaP nanoparticles into PCL/CS matrix via one-step electrospinning method, in order to endow the membrane with stimulation of osteogenesis and angiogenesis. The physicochemical properties, mechanical properties, Sr²⁺ release behavior, and the membrane stimulate bone mesenchymal stem cell (BMSCs) differentiation were evaluated in comparison with PCL/CS and CaP/PCL/CS membranes. The SEM images revealed that the nanocomposite membrane mimicked the extracellular matrix structure. The release curve presented a 28-day long continuous release of Sr²⁺ and concentration which was certified in an optimal range for positive biological effects at each timepoint. The in vitro cell culture experiments certified that the Sr-CaP/PCL/CS membrane enjoyed excellent biocompatibility and remarkably promoted rat bone mesenchymal stem cell (BMSCs) adhesion and proliferation. In terms of osteogenic differentiation, BMSCs seeded on the Sr-CaP/PCL/CS membrane showed a higher ALP activity level and a better matrix mineralization. What’s more, the synergism of the Sr²⁺ and CaP from the Sr-CaP/PCL/CS membrane enhanced BMSCs angiogenic differentiation, herein resulting in the largest VEGF secretion amount. Consequently, the Sr-CaP/PCL/CS nanohybrid electrospun membrane has promising applications in GBR.     

骨髓基质细胞-成骨细胞复合培养体系的建立

背景：在骨修复和重建过程中,成骨细胞和骨髓基质细胞是主要功能细胞,二者存在着密切的功能联系。 目的：通过骨髓基质细胞-成骨细胞共育体系的建立,观察共育体系中两种细胞之间的功能影响及生物学特点。 方法：原代分离人骨髓基质细胞和人成骨细胞,将2种细胞置于Transwell共育环境中共同培养,建立人骨髓基质细胞-成骨细胞共育体系。分别采用MTT、丫啶橙染色、碱性磷酸酶活性检测等方法初步评价共育体系中两种细胞增殖、凋亡及功能改变情况。 结果与结论：在复合培养体系中,骨髓基质细胞-成骨细胞共育体系能够促进成骨细胞的增殖与碱性磷酸酶的活性,同时抑制骨髓基质细胞的凋亡,促进骨髓基质细胞的趋化聚集。结果提示在复合培养体系中, 骨髓基质细胞能够加速成骨细胞的增殖及成骨活性,另外成骨细胞也可减少骨髓基质细胞的凋亡,并加强其成骨性分化的作用。两者之间具有较为紧密的影响和功能联系。     

RNA干涉抑制破骨细胞分化因子表达对骨髓基质细胞成骨成脂分化的影响

背景：RNA干涉是目前分子生物学研究领域重要的基因下调技术,护骨素/κB受体活化因子/破骨细胞分化因子偶联系统是目前骨改建平衡研究中的热点。 目的：应用RNA干涉特异性抑制大鼠骨髓基质细胞内破骨细胞分化因子基因的表达,研究破骨细胞分化因子表达下调后对骨髓基质细胞成骨成脂分化的影响。 方法：获取骨髓基质细胞,转染前24 h按5×105/孔接种于6 孔培养板中,分为实验组、阴性对照组和空白对照组,前2组细胞分别转染针对破骨细胞分化因子的siRNA或阴性对照siRNA。观察骨髓基质细胞增殖活性、碱性磷酸酶活性及Real-Time PCR检测成骨成脂基因mRNA的表达。 结果与结论：实验组碱性磷酸酶活性降低,RunX-2,骨形态发生蛋白2,4表达降低,而PPAR-γ和C/EBP-α的表达升高(P < 0.05)。提示,通过RNA干涉使骨髓基质细胞的破骨细胞分化因子表达下调对骨髓基质细胞成骨分化有抑制作用,而对成脂分化有促进作用。