辛伐他汀可刺激骨髓间充质干细胞的成骨分化

背景:辛伐他汀可显著刺激骨髓间充质干细胞成骨分化,但机制不明.近年研究证实p38 MAPK信号通路参与调控骨髓间充质干细胞向成骨细胞分化的过程.目的:观察p38丝裂原活化蛋白激酶(mitogen-activated protein kinase,MAPK)信号通路在辛伐他汀体外干预刺激骨髓间充质干细胞成骨分化中的作用....     

Cytocompatibility,osseointegration, and bioactivity of three-dimensional porous and nanostructured network on polyetheretherketone

Porous biomaterials with the proper three-dimensional (3D) surface network can enhance biological functionalities especially in tissue engineering, but it has been difficult to accomplish this on an important biopolymer, polyetheretherketone (PEEK), due to its inherent chemical inertness. In this study, a 3D porous and nanostructured network with bio-functional groups is produced on PEEK by sulfonation and subsequent water immersion. Two kinds of sulfonation-treated PEEK (SPEEK) samples, SPEEK-W (water immersion and rinsing after sulfonation) and SPEEK-WA (SPEEK-W with further acetone rinsing) are prepared. The surface characteristics, in vitro cellular behavior, in vivo osseointegration, and apatite-forming ability are systematically investigated by X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy, scanning electron microscopy, cell adhesion and cell proliferation assay, real-time RT-PCR analysis, micro-CT evaluation, push-out tests, and immersion tests. SPEEK-WA induces pre-osteoblast functions including initial cell adhesion, proliferation, and osteogenic differentiation in vitro as well as substantially enhanced osseointegration and bone-implant bonding strength in vivo and apatite-forming ability. Although SPEEK-W has a similar surface morphology and chemical composition as SPEEK-WA, its cytocompatibility is inferior due to residual sulfuric acid. Our results reveal that the pre-osteoblast functions, bone growth, and apatite formation on the SPEEK surfaces are affected by many factors, including positive effects introduced by the 3D porous structure and SO₃H groups as well as negative ones due to the low pH environment. Surface functionalization broadens the use of PEEK in orthopedic implants.     

Enhanced antibacterial property and osteo-differentiation activity on plasma treated porous polyetheretherketone with hierarchical micro/nano-topography

Implantable polyetheretherketone (PEEK) has great biomedical potential as hard tissue substitute in orthopedic application due to its outstanding mechanical properties and excellent biological stability. However, the poor osseointegration and bacteriostatic ability of implantable PEEK become the major barrier for its wide clinic application. In this study, a hierarchically micro/nano-topographic PEEK with specific functional groups (amino and COOH/COOR) has been fabricated using facile sulfonation combined with argon plasma treatment. The new developed hierarchically micro/nano-topographic PEEK have enhanced hydrophilicity, surface roughness, as well as the high ability of apatite-layer forming. Antibacterial assessment shows that as-treated samples exhibit better antibacterial activity. The cellular responses in osteoblast-like MG-63 cells culturing experiment reveal that the micro/nano-topography accompanied with specific functional groups improves the cell adhesion at the initial stage, further ameliorates proliferation and osteogenic differentiation of MG-63. This study proposes a promising approach to increase osteo-differentiation activity and bacteriostasis of PEEK via synergistic effects involving surface topologic structure and chemical modification, which shows great potential in developing advanced implantable materials.     

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。     

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。     

Effects of Simvastatin on the Phospholipid Composition of High-Density Lipoproteins in Patients with Hypercholesterolemia

We studied the phospholipid composition of high-density lipoproteins in patients with hypercholesterolemia before and after treatment with simvastatin. Individual phospholipids were separated by thin-layer chromatography on glass plates coated with silica gel. It was found that apart from hypolipidemic effect, simvastatin changed the concentration and phospholipid composition of high-density lipoproteins, which improved their cholesterol-accepting and cholesterol-transporting properties.     

Osseointegration of machined,injection moulded and oxygen plasma modified PEEK implants in a sheep model

Machined and injection moulded polyetheretherketone (PEEK) implants with and without an oxygen plasma modification were prepared and implanted in sheep cancellous and cortical bone. After 4, 12 and 26 weeks, osseointegration was evaluated through mechanical push-out tests and histomorphometry. In the cancellous bone, push-out force increased with time, a trend toward higher force was observed for machined compared to moulded, and oxygen plasma modified compared to unmodified. On-going remodelling of the bone was detected in the periphery of the implants at 4 weeks. Minimal or no inflammation was observed with all the implants at all locations and time-points. Bone-implant contact (BIC) was quantified at all-time points and locations for all the four PEEK implant surfaces. The BIC values ranged from 15 to 75% with an average of 29 ± 13% in the cancellous bone and 25–65% with an average of 50 ± 12% in the cortical bone. In the cortical bone the BIC increased significantly from 4 to 26 weeks. This in vivo study has identified that surface topography of PEEK implants influences osseointegration. In addition, oxygen plasma has the potential to increase bone-implant interface stability. This study provides a unique reference for further modifications and in vivo assessment of PEEK implants.     

Using co-axial electrospray deposition to eliminate burst release of simvastatin from microparticles and to enhance induced osteogenesis

Microparticles (MPs) exhibit fast dissolution, characterized by a burst drug release pattern. In the present work, we prepared core-shell MPs of simvastatin (SIM) and zein with chitosan (CS) and nano-hydroxyapatite (nHA) as a drug carrier using the coaxial electrospray deposition method. The morphology, formation and in vitro osteogenic differentiation of these MPs were studied. The synthetic MPs have a diameter of about 1?μm and they are composed of non-toxic natural materials. They provide an effective way to enable long-term sustained-release activity, which is controlled by their double layer structures. The CS-nHA/zein-SIM MPs presented a low initial burst release (approximately 35–47%) within the first 24?h of application followed by the sustained release for at least 4?weeks. In vitro cell culture experiments were performed and the results revealed that the CS-nHA/zein-SIM core-shell MPs were beneficial to the adhesion, proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs). The CS-nHA/zein-SIM MPs with a low SIM concentration were beneficial to cell proliferation and promotion of osteogenic differentiation.     

骨组织工程种子细胞的研究进展

随着骨组织工程研究的进展 ,选择什么细胞作为其种子细胞成为近年来研究的热点。目前 ,骨组织工程应用中种子细胞有五种来源 :骨、骨膜、骨髓、骨外组织和早期胚胎。本文介绍了五种来源种子细胞的研究状况 ,并对种子细胞各自存在的问题及应用前景进行了分析。     

辛伐他汀和吉非罗齐对高脂血症伴骨量减少患者骨代谢和骨密度的影响

目的观察辛伐他汀和吉非罗齐对高胆固醇血症伴骨量减少患者骨代谢指标及骨密度的影响。方法高脂血症合并骨量减少患者128例,分两组后分别予以辛伐他汀和吉非罗齐治疗,并在治疗前及治疗后分别检测血脂、骨吸收标志物血清I型胶原羧基末端肽（sCTX）、骨形成标志物总骨Ⅰ型前胶原N端肽（P1NP）和桡骨远端骨密度（BMD）。结果辛伐他汀组平均治疗周期（10.24±1.89）个月,治疗后总胆固醇（TC）、甘油三酯（TG）、低密度脂蛋白（LDL-C）明显降低（P〈0.05）,同时sCTX降低（P〈0.01）,P1NP增高（P〈0.05）,BMD增加（P〈0.01）,而吉非罗齐治疗后虽TC、TG、LDL-C明显降低（P〈0.05）但sCTX、P1NP和BMD无明显变化。结论较大剂量辛伐他汀具有抑制骨吸收、增强骨形成和增加BMD的作用,可能与血脂水平降低无关。     

In vivo leptin expression in cartilage and bone cells of growing rats and adult humans

The present investigation was carried out to analyse, immunohistochemically, in vivo leptin expression in cartilage and bone cells, the latter restricted to the elements of the osteogenic system (stromal cells, osteoblasts, osteocytes, bone lining cells). Observations were performed on the first lumbar vertebra, tibia and femur of four rats and on the humerus, femur and acromion of four patients. Histological sections of paraffin-embedded bone samples were immunostained using antibody to leptin. The results showed that, in growing rat bone, leptin is expressed in chondrocytes and stromal cells, but not in osteoblasts; bone lining cells were not found in the microscopic fields examined. In adult human bone, leptin is expressed in chondrocytes, stromal cells and bone lining cells; osteoblasts were not found in the microscopic fields examined. Osteocytes were found to be leptin positive only occasionally and focally in both rat and human bone. The in vivo findings reported show, for the first time, that leptin appears to be expressed only in the cells of the osteogenic lineage (stromal cells, bone lining cells, osteocytes) that, with respect to osteoblasts, are permanent and inactive, i.e. in those cells that according to our terminology constitute the bone basic cellular system (BBCS). Because the BBCS seems to be primarily involved in sensing and integrating mechanical strains and biochemical factors and then in triggering and driving bone formation and/or bone resorption, it appears that leptin seems to be mainly involved in modulating the initial phases of bone modelling and remodelling processes.     

骨组织工程的种子细胞--骨髓基质细胞的研究进展

骨髓基质细胞作为骨组织工程的种子细胞具有广阔前景.许多实验证实骨髓基质细胞具有间充质干细胞特性,表现为较强的增殖能力和向多种间充质细胞分化的潜能.目前已建立了体外培养骨髓基质干细胞的方法,而且正在摸索进一步纯化的方法和诱导分化的条件.已有利用其成骨特性体内移植实验,表明在适当的条件下,接种在组织工程材料上的骨髓基质细胞可以形成新骨.     

辛伐他汀对糖尿病高脂血症患者体内炎症水平和颈动脉斑块的影响

目的:探讨辛伐他汀对糖尿病高脂血症患者体内炎症水平和动脉斑块的影响.方法:120例2型糖尿病(DM2)合并高脂血症患者,给予控制血糖,每晚给予辛伐他汀片20mg口服,持续12周.观察患者血脂、hs-CRP、TNF-α及颈动脉斑块的变化.结果:患者经辛伐他丁治疗后血清TC、TG和LDL-C水平均较治疗前有明显降低(P<0...     

兔胫骨截骨延长区愈合过程的病理学观察

目的 :探讨截骨延长区骨愈合的病理学特点和新骨形成规律。方法 :取健康兔 2 7只建立胫骨骨延长动物模型 ,分别于延长的第 0、1、3、5、10、15、2 0、30、40天处死动物 ,在延长区取材进行病理组织学观察 ,同时用抗骨形成蛋白 (BMP)单抗作免疫组化染色。结果 :延长前即出现血肿 ,延长第 1天血肿机化 ,第 3天出现新的血肿 ,第 5天软骨形成和新血肿机化 ,第 15天出现膜内成骨、纤维性成骨和软骨内成骨 ,第 2 0天延长区大部分被骨性骨痂取代 ,第 30天开始改建。免疫组化染色显示延长区纤维母细胞、骨母细胞和软骨细胞均不同程度表达BMP。结论 :延长区存在膜内成骨、纤维性成骨和软骨内成骨 3种方式 ,以软骨内成骨为主 ;内源性BMP参与了延长区愈合过程。     

辛伐他汀与BMP-2促进兔桡骨骨折愈合的对比观察研究

目的探讨辛伐他汀促进骨折愈合的效果。方法建立兔单侧桡骨骨折(3mm)模型36只,按照随机原则分为A、B、C3组,每组12只。A组为空白对照组,予以0.9%氯化钠溶液灌胃,骨折局部注射0.9%氯化钠溶液;B组为骨形态发生蛋白-2(BMP-2)对照组,予以0.9%氯化钠溶液灌胃,骨折局部注射BMP-2溶液;C组为辛伐他汀实验组,予以辛伐他汀配置液灌胃,骨折局部注射0.9%氯化钠溶液。在术后2、4、8周通过X射线摄片、病理组织切片、骨密度测定及生物力学测定(仅在第8周)等指标来观测评估骨折愈合情况,并分析各组骨折愈合程度差异有无统计学意义。结果 X射线摄片检查:在术后各个时间点,B组和C组在骨痂的形成改建及骨髓腔的再通上均要优于A组,而B、C两组间差异无统计学意义(P>0.05)。骨密度测定:术后2、4周时,C组、B组均优于A组,差异有统计学意义(P<0.05);且在第2周时B组要优于C组,差异有统计学意义(P<0.05);在第4周时,B组与C组差异无统计学意义(P>0.05)。在术后第8周时,A组要优于B组与C组,差异有统计学意义(P<0.05),而B组与C组差异无统计学意义(P>0.05)。生物力学测定(第8周时):B组和C组均高于A组,差异有统计学意义(P<0.05);B组和C组比较,差异无统计学意义(P>0.05)。组织形态学检查:C组和B组在胶原纤维、软骨组织、骨小梁及骨基质的形成时期均早于A组,B组和C组之间差异无统计学意义。结论辛伐他汀有良好的成骨作用;辛伐他汀可以促进骨折愈合,效果与BMP-2接近。     

骨形态发生蛋白2信号通路与骨发生发育及损伤修复

背景：骨形态发生蛋白在骨形成过程中、骨折愈合后以及骨质破坏后骨诱导方面起着重要作用,它可以作为启动调节因子和别的信号通路共同促进新骨形成。内源性骨形态发生蛋白2的调节可以作为未来骨修复领域的一个新的靶点。 目的：通过分析和总结1988年以来骨形态发生蛋白信号传导通路在软骨内成骨、维持成人骨骼生长发育中的作用机制,探索骨形态发生蛋白信号通路在骨的发育以及损伤修复中的作用。 方法：分别以“骨形态发生蛋白、软骨内成骨、骨修复”,“bone  reduction”为检索词,应用计算机检索重庆维普(VIP)期刊全文数据库及PubMed 数据库1998年1月至2009年12月有关文章。纳入有关骨形态发生蛋白信号通路及其作用的文献。排除与研究目的无关和内容重复者。保留34篇文献做进一步分析。 结果与结论：骨形态发生蛋白信号通路诱导骨再生潜能在脊柱外科手术、骨折后愈合以及骨破坏后骨诱导等诸多领域成为研究热点。在骨形成过程中,骨形态发生蛋白也作为启动调节因子和别的信号通路相互影响共同促进新骨形成,出生后,骨形态发生蛋白也参与骨骼动态平衡的维持。在骨的微环境中,骨形态发生蛋白和其他影响骨质动态平衡的信号通路共同为诱导骨形成的合成代谢疗法提供了一个新靶点,这为骨修复时骨形态发生蛋白控制新骨的形成提供了一个新的思路。     

骨髓基质干细胞与骨基质明胶复合培养体内异位成骨的实验研究

目的：探讨骨髓基质干细胞(MSC)与骨基质明胶复合培养体内异位成骨的可行性。方法：将SD大鼠来源的MSC与同种异体的骨基质明胶复合培养后植入SD大鼠背部竖脊肌肌膜内，分别于术后不同的时间点处死大鼠，标本进行碱性磷酸酶(ALP)活性测定及组织形态学观察：结果：实验组标本自术后第3周ALP活性起就表现出阳性，第4周MSC与骨基质明胶复合体内大量成骨。结论：MSC与骨基质明胶复合培养体内异位成骨完全可行的。     

Simvastatin and Preparation of Polyunsaturated Phospholipids Produce Similar Changes in the Phospholipid Composition of High-Density Lipoproteins during Hypercholesterolemia

We studied the phospholipid composition of high-density lipoproteins in patients with coronary heart disease and hypercholesterolemia treated with simvastatin (Zocor, inhibitor of the key enzyme of cholesterol synthesis) and preparation of polyunsaturated phospholipids (lipostabil forte). Simvastatin produced a hypolipidemic effect and modulates the phospholipid composition of high-density lipoproteins (similarly to lipostabil forte). These changes contribute to functional activity of high-density lipoproteins in the reverse cholesterol transport.__________Translated from Byulleten Eksperimentalnoi Biologii i Meditsiny, Vol. 139, No. 2, pp. 178–180, February, 2005     

Enhancing bioactivity of chitosan film for osteogenesis and wound healing by covalent immobilization of BMP-2 or FGF-2

This study compares the efficacy of growth factors that are covalently immobilized to those that are adsorbed in improving the bioactivity of a biomaterial. Bone morphogenetic protein-2 (BMP-2) or fibroblast growth factor-2 (FGF-2) was covalently bonded to chitosan films using carbodiimide chemistry. For BMP-2, a growth factor loading efficiency of ～64% was obtained with this method compared to ～25% from adsorption. As for FGF-2, the growth factor loading efficiency of the two methods was similar at ～50%. The covalently immobilized BMP-2 promoted attachment, proliferation, and differentiation of osteoblasts in a dose-dependent manner, whereas the covalently immobilized FGF-2 stimulated fibroblast attachment, proliferation, and collagen synthesis. After three?weeks immersion in phosphate buffered saline, about 80% of the covalently immobilized growth factors were retained on the films, while only ～16 and ～21% of the adsorbed BMP-2 and FGF-2 remained on the corresponding films. The higher retention rate of the covalently immobilized growth factors enabled their stimulatory effects to persist for a longer period than when adsorbed growth factors were used.