Interactions between MC3T3-E1 cells and textured Ti6Al4V surfaces

This paper presents the results of an experimental study of the interactions between MC3T3-E1 (mouse calvarian) cells and textured Ti6Al4V surfaces, including surfaces produced by laser microgrooving; blasting with alumina particles; and polishing. The multiscale interactions between MC3T3-E1 cells and these textured surfaces are studied using a combination of optical scanning transmission electron microscopy and atomic force microscopy. The potential cytotoxic effects of microchemistry on cell-surface interactions also are considered in studies of cell spreading and orientation over 9-day periods. These studies show that cells on microgrooved Ti6Al4V geometries that are 8 or 12 microm deep undergo contact guidance and limited cell spreading. Similar contact guidance is observed on the surfaces of diamond-polished surfaces on which nanoscale grooves are formed due to the scratching that occurs during polishing. In contrast, random cell orientations are observed on alumina-blasted Ti6Al4V surfaces. The possible effects of surface topography are discussed for scar-tissue formation and improved cell-surface integration.     

Grooves affect primary bone marrow but not osteoblastic MC3T3-E1 cell cultures

To elucidate the influence of microtextures on bone cell performance, primary adult rat bone marrow cells (RBMC) and osteoblastic MC3T3-E1 cells were cultured on tissue culture pretreated plates to which grooves at different density were applied. RBMC cells were found to be significantly affected by grooves in the substratum in contrast to osteoblastic MC3T3-E1 cells, taking culture morphology, total cell number, cell mass, and cell activity (MTT-dehydrogenase), parameter for differentiation of osteoblast progenitor cells into (pre-)osteoblasts (alkalinephosphatase activity, ALP) and tartrate-resistant acid phosphatase (TRAP) activity as indices. TRAP is located in lysosomes and secretory granules mainly although not solely in osteoclasts. By applying grooves to and/or by chemical treatment of unpretreated pure polysterene plates it could be concluded that the effects on RBMC cells were evoked not only by the presence of grooves but also by the surface chemistry of the grooved and ungrooved surface areas.     

Exposed hydroxyapatite particles on the surface of photo-crosslinked nanocomposites for promoting MC3T3 cell proliferation and differentiation

We present a systematic study for investigating the role of exposed hydroxyapatite (HA) nanoparticles in influencing surface characteristics and mouse pre-osteoblastic MC3T3-E1 cell behavior using nanocomposites prepared by photo-crosslinking poly(ε-caprolactone) diacrylate (PCLDA) with HA. PCLDA530 and PCLDA2000 synthesized from poly(ε-caprolactone) diol precursors with nominal molecular weights of 530 and 2000 g mol(-1) were used as the polymer matrices. Crosslinked PCLDA530 was amorphous while crosslinked PCLDA2000 was semi-crystalline. Crosslinked PCLDA/HA composites with different compositions of HA (10%, 20% and 30%) as well as crosslinked PCLDAs were characterized in terms of their composition-dependent physicochemical properties. The tensile, compressive and shear moduli were greatly enhanced by incorporating HA nanoparticles with the polymer matrices. The disk surfaces of original crosslinked PCLDA/HA nanocomposites were removed by cutting using a blade to expose HA nanoparticles that were embedded in the polymer substrates. The composition of HA was much higher on the cut surface, particularly in semi-crystalline crosslinked PCLDA2000/HA nanocomposites. The surface characteristics of original and cut crosslinked PCLDA/HA nanocomposites were compared and correlated with cell behavior on these nanocomposites. MC3T3-E1 cell attachment, proliferation and differentiation were significantly enhanced when the HA composition was increased in original crosslinked PCLDA/HA nanocomposites due to more bioactive HA, higher surface stiffness and rougher topography. More exposed HA on the surface of cut semi-crystalline PCLDA2000/HA nanocomposites resulted in improved hydrophilicity and significantly better MC3T3 cell attachment, proliferation and differentiation compared with the original surfaces. This study suggests that HA nanoparticles may not be fully exploited in polymer/HA nanocomposites where the top polymer surface covers the particles. The removal of this polymer layer can generate more desirable surfaces and osteoconductivity for bone repair and regeneration.     

Tmed2促进体外小鼠前成骨细胞MC3T3-E1增殖

 摘要：目的 研究Tmed2基因对小鼠前成骨细胞增殖的影响。 方法 1.分别在小鼠MC3T3-E1细胞中过表达和抑制Tmed2,检测细胞增殖情况。2. 用雌激素处理细胞后,检测细胞的增殖及Tmed2基因的表达量。荧光实时定量PCR检测mRNA水平,MTS法检测细胞活力和增殖,流式细胞术检测细胞周期,Western blot法检测蛋白水平。结果 过表达Tmed2使MC3T3-E1细胞的增殖速度加快,细胞周期中S期细胞比例明显增加,且Cyclin A 的表达升高。而抑制Tmed2基因表达使MC3T3-E1细胞的增殖速度减慢。雌激素处理使细胞增殖速度加快的同时,Tmed2基因的表达显著增高。结论 Tmed2通过上调Cyclin A 的表达,使S期细胞比例增加,加快小鼠前成骨细胞MC3T3-E1的增殖。此外,Tmed2的表达受雌激素的调控,可能参与雌激素促进MC3T3-E1细胞增殖的作用。     

Influence of multilayer rhBMP-2 DNA coating on the proliferation and differentiation of MC3T3-E1 cells seeded on roughed titanium surface

For bone morphogenetic protein (BMP) gene therapy to be a viable approach for enhancing implant osseointegration clinically, requires the development of efficient nonviral delivery vectors that can coat the implant. This study evaluated a multilayer cationic liposome-DNA complex (LDc) coating as a delivery vehicle for recombinant human BMP-2 (rhBMP-2). Multilayered coatings, comprising hyaluronic acid (HA) and LDc, were fabricated onto titanium using a layer-by-layer (LBL) assembly technique. Preosteoblastic MC3T3-E1 cells were cultured on the roughened titanium surfaces coated with multilayers of HA/LDc, or on uncoated or HA/liposome only surfaces as controls. The amount of rhBMP-2 secreted by the MC3T3-E1 cells and the effect of the various surfaces on cell viability, proliferation, alkaline phosphatase (ALP) activity, osteocalcin (OC) secretion, and calcium deposition were evaluated. Messenger RNA levels of OC, ALP, Runx2, and Osx were also investigated. The results demonstrated that rhBMP-2 protein secreted into culture medium at 3 days was significantly higher than control groups. MC3T3-E1 cells cultured on the HA/LDc coating displayed significantly higher ALP activity and OC secretion at 7 days and 14 days culture, respectively. MC3T3-E1 cells cultured on HA/LDc upregulated expression of the osteoblast differentiation markers, especially on days 12 for OC and on days 6 and 12 for ALP and Osx. In conclusion, MC3T3-E1 cell cultured on the multilayer HA/LDc coating surface can secret rhBMP-2 protein and the protein levels were effective in inducing early osteogenic differentiation. ? 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A 100A: 2766-2774, 2012.     

miR-132-3p过表达对MC3T3-E1细胞增殖分化的影响

文题释义： miRNA：是一类小的非编码RNA,长度约为22个核苷酸,其主要通过结合靶标mRNA的3'UTR区诱导靶标mRNA降解或抑制其翻译,从而在转录及转录后水平调控相关基因的表达。miRNA在细胞增殖、分化及凋亡等多种生物学活动过程中起着非常重要的调控作用,并且发现它是调控骨组织细胞增殖和分化过程的重要因子之一。 MC3T3-E1细胞：是新生C57BL/6小鼠颅顶骨中分离培养所建立的一株成骨细胞株,它能够展现骨组织中成骨细胞的各个发育阶段和各种生物学特性。作为研究成骨细胞增殖和分化的理想模型,被广泛应用于国内外各种骨组织工程学研究。 背景：机械牵引力能够影响MC3T3-E1细胞的增殖分化过程,并引起细胞内miR-132-3p的差异表达。然而,牵引力是否通过调控miR-132-3p的表达来影响成骨细胞增殖分化仍需进一步研究。 目的：明确12%牵引力作用下MC3T3-E1细胞中成骨分化标志因子及miR-132-3p表达变化,并进一步探讨miR-132-3p对细胞增殖分化的影响。 方法：MC3T3-E1细胞分别加载0%,12%牵张应力,检测应力加载后碱性磷酸酶活性、骨钙蛋白及miR-132-3p mRNA的表达水平;细胞内瞬时转染miR-132-3p模拟物及其阴性对照,qRT-PCR检测转染后碱性磷酸酶、骨钙蛋白、Runt标志转录因子2 mRNA的表达,CCK-8法检测miR-132-3p对细胞增殖能力的影响。 结果与结论：①12%牵张应力作用下,MC3T3-E1细胞中碱性磷酸酶活性、骨钙蛋白mRNA表达水平下调(P < 0.01),miR-132-3p表达水平显著升高(P < 0.05);②细胞内转染miR-132-3p后,miR-132-3p模拟物组成骨分化标志因子碱性磷酸酶、骨钙蛋白、Runt标志转录因子2 mRNA表达水平显著降低(P < 0.05);③相比于阴性对照组,miR-132-3p 模拟物转染24,48,72 h后细胞增殖能力明显降低(P < 0.001),且在转染48 h后降低最明显;④结果说明12%周期性循环牵张应力能够通过过表达miR-132-3p负向调节MC3T3-E1细胞的增殖和成骨分化。 ORCID: 0000-0003-0696-3329(孙芬) 中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程     

人牙周膜干细胞来源外泌体干预成骨细胞MC3T3-E1的增殖和分化

背景:人牙周膜干细胞具有较强的成骨分化能力,人牙周膜干细胞来源外泌体作为牙周膜干细胞分泌的主要成分,对成骨细胞MC3T3-E1增殖和成骨分化的影响尚不明确。目的:探讨人牙周膜干细胞来源外泌体对MC3T3-E1细胞增殖和分化的影响。方法:采用酶消化法分离及培养人牙周膜干细胞,超速离心法提取人牙周膜干细胞来源外泌体,通过透射电镜、粒径分析及Western blot方法对人牙周膜干细胞来源外泌体进行鉴定;CCK8法检测不同质量浓度人牙周膜干细胞来源外泌体对MC3T3-E1细胞增殖的影响,茜素红染色观察100 mg/L人牙周膜干细胞来源外泌体对MC3T3-E1细胞成骨矿化的影响,Western blot检测100 mg/L人牙周膜干细胞来源外泌体干预前后MC3T3-E1细胞内MEK和ERK的磷酸化水平。结果与结论:①透射电镜观察可见外泌体为脂质双分子层形成的囊泡结构,粒径检测显示外泌体直径分布在50-120 nm,集中在79.86 nm,Western blot检测结果显示提取的外泌体中含有CD81,CD63,TSG101的表达;②与对照组相比,人牙周膜干细胞来源外泌体对MC3T3-E1细胞的增殖具有促进作用,且作用呈剂量依赖性;③与对照组相比,人牙周膜干细胞来源外泌体组MC3T3-E1细胞能够形成更多的钙结节;与对照组相比,人牙周膜干细胞来源外泌体组MC3T3-E1细胞内p-MEK及p-ERK蛋白表达量升高;④结果表明,人牙周膜干细胞来源外泌体可以显著促进MC3T3-E1增殖和成骨分化,推测可能与其激活MEK/ERK信号通路有关。     

The relative influence of the topography and chemistry of TiAl6V4 surfaces on osteoblastic cell behaviour

Proliferation and adhesion of mouse (MC3T3-E1) osteoblastic cells and primary human osteoblastic cells were carried out on Ti6Al4V titanium alloy samples with varied surface roughnesses. Mechanically or manually polished surfaces were prepared to produce respectively non-oriented or oriented residual polishing grooves. Sand-blasted surfaces were prepared using 500 microm or 3 mm alumina particles. Surface roughness parameters showed a negative correlation in comparison to proliferation and adhesion parameters. X-ray microprobe chemical surface microanalysis showed complete disturbance of the surface element composition of the Ti6Al4V alloy following sand-blasting treatment. An AlOx-enriched layer was observed on sample surfaces. This may lead to the suspicion that the concomittant effect of surface roughness amplitude and AlOx surface concentration has an effect on osteoblastic cell proliferation and adhesion. These findings show the significance of chemical surface analysis after any surface treatment of titanium-based implants before any biological use.     

Txndc5介导雌激素诱导的小鼠前成骨细胞MC3T3-E1增殖加快

 目的 研究Txndc5基因在小鼠前成骨细胞增殖中的作用。 方法 用雌激素诱导小鼠前成骨细胞系MC3T3-E1,或在MC3T3-E1细胞中分别用质粒载体过表达Txndc5和用siRNA抑制Txndc5的表达后,Western blot检测Txndc5和细胞周期蛋白水平,荧光实时定量PCR检测Cyclin A的mRNA水平,MTS法和细胞计数法检测细胞增殖速度,流式细胞术检测细胞周期。 结果 雌激素诱导MC3T3-E1增殖加快时,Txndc5的蛋白水平亦上升。抑制Txndc5的表达阻止雌激素的促细胞增殖作用。过表达Txndc5使MC3T3-E1细胞增殖速度加快,S期细胞比例增加,同步化细胞进入细胞周期18h时,过表达Txndc5组Cyclin A 的表达升高,且S期细胞比例为18.69%±4.08%,而对照组仅为8.15%±3.68%。抑制Txndc5的表达则使MC3T3-E1细胞增殖速度减慢,S期细胞比例减少,Cyclin A 的表达下降。抑制Cyclin A的表达减弱Txndc5的促细胞增殖作用。结论 Txndc5通过上调Cyclin A 的表达介导雌激素的促前成骨细胞增殖作用。     

MC3T3-E1细胞与多组分纳米羟基磷灰石基三维复合支架材料的相容性

目的 观察MC3T3-E1细胞在复合支架材料上的黏附、增殖及形态,评价多组分纳米羟基磷灰石基三维复合支架材料的生物相容性.方法 采用仿生学方法,将壳聚糖、羟基磷灰石、明胶、果胶按照一定比例制作成多组分纳米羟基磷灰石基三维复合支架材料.在复合支架材料上接种MC3T3-E1细胞,通过倒置相差显微镜、HE染色、扫描电镜、四甲...     

Three-dimensional bioactive glass implants fabricated by rapid prototyping based on CO(2) laser cladding

Three-dimensional bioactive glass implants were produced by rapid prototyping based on laser cladding without using moulds. CO(2) laser radiation was employed to melt 45S5 and S520 bioactive glass particles and to deposit the material layer by layer following a desired geometry. Controlled thermal input and cooling rate by fine tuning of the processing parameters allowed the production of crack-free fully dense implants. Microstructural characterization revealed chemical composition stability, but crystallization during processing was extensive when 45S5 bioactive glass was used. Improved results were obtained using the S520 bioactive glass, which showed limited surface crystallization due to an expanded sintering window (the difference between the glass transition temperature and crystallization onset temperature). Ion release from the S520 implants in Tris buffer was similar to that of amorphous 45S5 bioactive glass prepared by casting in graphite moulds. Laser processed S520 scaffolds were not cytotoxic in vitro when osteoblast-like MC3T3-E1 cells were cultured with the dissolution products of the glasses; and the MC3T3-E1 cells attached and spread well when cultured on the surface of the materials.     

Spatial and temporal changes in the morphology of preosteoblastic cells seeded on microstructured tantalum surfaces

It has been widely reported that surface morphology on the micrometer scale affects cell function as well as cell shape. In this study, we have systematically compared the influence of 13 topographically micropatterned tantalum surfaces on the temporal development of morphology, including spreading, and length of preosteoblastic cells (MC3T3-E1). Cells were examined after 0.5, 1, 4, and 24 h on different Ta microstructures with vertical dimensions (heights) of 0.25 and 1.6 mum. Cell morphologies depended upon the underlying surface topography, and the length and spreading of cells varied as a function of time with regard to the two-dimensional pattern and vertical dimension of the structure. Microstructures of parallel grooves/ridges caused elongated cell growth after 1 and 4 h in comparison to a flat, nonstructured, reference surface. For microstructures consisting of pillars, cell spreading was found to depend on the distance between the pillars with one specific pillar structure exhibiting a decreased spreading combined with a radical change in morphology of the cells. Interestingly, this morphology on the particular pillar structure was associated with a markedly different distribution of the actin cytoskeleton. Our results provide a basis for further work toward topographical guiding of cell function.     

聚醚醚酮表面多孔羟基化改性对MC3T3-E1细胞黏附、增殖的影响

目的对聚醚醚酮(polyetheretherketone,PEEK)薄片表面进行多孔化和羟基化改性,观察PEEK表面形貌和生物活性的变化,并探讨该改性方法对前成骨MC3T3-E1细胞黏附、增殖的影响。方法超声波环境下浓硫酸处理PEEK表面,在其表面形成大量微孔结构;经湿化学法将PEEK表面的酮类基团还原成羟基基团,改善其表面化学活性,提升PEEK薄片的生物相容性。利用扫描电子显微镜(SEM)、傅里叶变换红外光谱仪(FTIR)及静态水接触角检测改性前后材料表面形貌、化学基团及亲水性的变化。未处理PEEK、多孔化PEEK、羟基化PEEK、多孔羟基化PEEK与MC3T3-E1细胞共培养,评价表面改性后PEEK薄片对细胞黏附、增殖的影响。结果 SEM结果显示浓硫酸处理后的PEEK薄片表面形成密集的空隙大小均匀的微孔结构,FT-IR结果证实羟基化改性成功地在PEEK表面还原出了大量羟基基团。同时,表面多孔化和羟基化改性均可有效提升PEEK材料表面的亲水性能。在体外细胞实验中,不同改性的PEEK材料与MC3T3-E1细胞共培养后结果显示,多孔化、羟基化和多孔羟基化改性均可显著促进细胞黏附和伸展,同时随着时间的延长,其促进细胞增殖的功能也逐步增强。结论表面多孔羟基化改性能有效提高PEEK材料表面的生物学活性和亲水性能,进而显著促进细胞的黏附和增殖。     

周期性机械牵拉通过上调Runx2表达促进MC3T3-E1细胞迁移

目的 探究周期性牵拉对小鼠胚胎成骨细胞MC3T3-E1迁移功能的影响及其相关机制。方法 使用应变加载系统对体外培养的MC3T3-E1细胞施加15%幅度的牵拉,模拟细胞体内受力情况。使用划痕愈合实验检测MC3T3-E1细胞的迁移功能,使用蛋白免疫印迹法检测Runx2表达情况,使用RNA干扰技术特异性降低Runx2表达量。结果 幅度15%、频率1.25 Hz、持续24 h的周期性机械牵拉可以促进MC3T3-E1细胞的迁移,升高细胞内Runx2表达水平。在静态培养条件下,干扰Runx2能抑制MC3T3-E1细胞的迁移。干扰MC3T3-E1细胞中Runx2表达可以部分降低机械牵拉对细胞迁移的促进效应。结论 周期性牵拉可以促进MC3T3-E1细胞的迁移,在此过程中Runx2可能发挥重要作用。研究结果为寻找促进骨折愈合的创新临床治疗方法提供实验依据。     

The precision structural regulation of PLLA porous scaffold and its influence on the proliferation and differentiation of MC3T3-E1 cells

A thermal-induced phase separation combined sugar template method was used to fabricate the Poly (L-lactide) acid (PLLA) scaffolds with precisely regulated porous structure. The effect of tuned porous structure of scaffolds on osteoblasts proliferation and differentiation was investigated. The results showed that the pore diameters (200–300, 300–400, 400–500 μm), porosity and interconnectivity of PLLA scaffolds can be accurately controlled indicated by scanning electron microscope. The results of cell experiments showed that the porous structure including the pore size and interconnectivity of scaffolds dramatically influence the cell proliferation and differentiation. The scaffold with pore diameter of 400–500 μm exhibited the highest cell viability and alkaline phosphatase activity among all the scaffolds for the MC3T3-E1 cells. The higher cell proliferation and biocompatibility observed in the 400–500 μm scaffold indicated the high selectivity for MC3T3-E1cells on the pore size of scaffold in tissue engineering. The precise control of the porous structure of scaffold may better guide the cell–matrix interaction in the future research.     

Surface patterning of poly(L-lactide) upon melt processing: in vitro culturing of fibroblasts and osteoblasts on surfaces ranging from highly crystalline with spherulitic protrusions to amorphous with nanoscale indentations

Large-scale and reproducible manufacturing of scaffolds for tissue engineering applications will necessitate the adoption of methods relying on the processing of the biodegradable polymers directly from the melt. Such solventless processing will give rise to bulk and surface properties that will differ significantly from those generated upon processing from solution-based methods. Thus, detailed understanding of the microstructures that are developed during melt processing and the resulting surface/cell interactions is needed. Here, surfaces of melt-cast poly(L-lactide) (PLLA) were patterned to furnish membrane samples with a wide range of crystallinity and significant differences in surface topographies, ranging from highly crystalline (60%) with spherulitic protrusions at the surface to amorphous with nanoscale indentations. The PLLA membranes were used to culture in vitro mouse 3T3-Swiss albino fibroblast cells and osteoblast-like MC3T3-E1 cells. The growth rates of 3T3 fibroblasts were significantly lower on highly crystalline PLLA membranes with spherulitic protrusions in comparison to crystalline PLLA without spherulitic protrusions and amorphous surfaces with 5-10-nm-deep indentations. However, the differences in the growth rates of osteoblast-like cells cultured on the PLLA membranes with different surface patterns were only marginally different.     

The behavior of MC3T3-E1 cells on chitosan/poly-L-lysine composite films: effect of nanotopography, surface chemistry, and wettability

In the present work, a series of composite films were produced from chitosan/poly-L-lysine blend solutions. The surface topography, chemistry, and wettability of composite films were characterized by atomic force microscopy (AFM), attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, and contact angle assay, respectively. For all composite films, blending with poly-L-lysine induced changes in surface chemistry and wettability. Interestingly, it was also found that increasing poly-L-lysine weight fraction in blend solutions could result in different nanoscaled surface topographic features, which displayed particle-, granule-, or fiber-dominant morphologies. MC3T3-E1 osteoblast-like cells were cultured on all composite films to evaluate the effects of surface nanotopography, chemistry, and wettability on cell behavior. The observations indicated that MC3T3-E1 cell behavior was affected by surface topography, chemistry, and wettability simultaneously and that cells showed strong responses to surface topography. On fiber-dominant surface, cells fully spread with obvious cytoskeleton organization and exhibited significantly higher level of adhesion and proliferation compared with particle- or granule-dominant surfaces. Furthermore, fiber-dominant surface also induced greater expression of mature osteogenic marker osteocalcin and higher mineralization based on RT-PCR and von Kossa staining. The results suggest that topographic modification of chitosan substratum at the nanoscale may be exploited in regulating cell behavior for its applications in tissue engineering.     

盐酸小檗碱通过PI3K/Akt信号通路促进小鼠前成骨细胞MC3T3-E1的分化

目的:研究盐酸小檗碱对小鼠前成骨细胞系MC3T3-E1分化与矿化的调控作用及其机制。方法:MC3T3-E1细胞给予不同浓度(0、1、5、10和20 mg/L)的盐酸小檗碱刺激3 d,CCK-8法检测细胞活性。不同浓度的盐酸小檗碱分别干预3 d和7 d,检测细胞碱性磷酸酶(ALP)活性。进一步将实验随机分为4组:对照组、盐酸小檗碱组、盐酸小檗碱+LY249002(PI3K/Akt通路抑制剂)组及LY249002组。干预2 d后,采用real-time PCR检测成骨细胞分化相关因子ALP、骨钙素(OCN)、骨桥蛋白(OPN)及Runt相关转录因子2(Runx2)的mRNA表达情况,采用Western blot检测PI3K/Akt信号通路相关蛋白p-Akt的表达水平。将MC3TC-E1细胞用矿化培养基诱导21 d,茜素红染色检测其矿化情况。结果:与对照组相比,不同浓度的盐酸小檗碱对细胞活性的影响没有明显差异;不同浓度的盐酸小檗碱处理MC3T3-E1细胞后ALP活性有不同程度升高。Real-time PCR结果表明,盐酸小檗碱(5 mg/L)促进ALP、OCN、OPN及Runx2的mRNA表达(P 0. 01),而LY294002能抑制这些分化相关因子的表达。Western blot检测结果表明,盐酸小檗碱(5 mg/L)促进p-Akt蛋白的表达(P 0. 01),其作用被LY249002抑制。茜素红染色发现盐酸小檗碱组矿化明显,但LY294002能抑制盐酸小檗碱的促进作用。结论:盐酸小檗碱可以促进小鼠前成骨细胞的分化与矿化,其机制可能与其激活PI3K/Akt信号通路有关。     

Enhanced osteogenic promotion around dental implants with synthetic binding motif mimicking bone morphogenetic protein (BMP)-2

Synthetic receptor binding motif mimicking bone morphogenetic protein-2 (BMP-2) was covalently linked to titanium (Ti) surfaces through a chemical conjugation process. The composition and properties of surface-modified Ti were investigated by XPS as well as by measuring surface radioactivity. In vitro tests were conducted with osteoblast-like MC3T3-E1 cells to assess cell attachment, morphology, and expression of osteogenic marker in the cells grown on modified Ti surfaces. In addition, in vivo experiments involved implants in mandibular bone defects of beagles to evaluate the effect of surface modification on bone regeneration. Results of XPS measurements showed a complete and homogeneous peptide overlayer on the Ti surfaces; the content was further measured by gamma counting. Biological evaluations showed that the biochemically modified Ti samples were active in terms of cell attachment behavior. The MC3T3-E1 cell growth rate, marker protein expression, and alkaline phosphatase production of the peptide-modified surfaces were all higher than those of control Ti. Importantly, the implants in the canine mandibles showed significant increase of bone growth when modified with bioactive peptide, thereby confirming that biochemical modifications of Ti surfaces can enhance the rate of bone healing as compared with untreated Ti surfaces.