关键词： Asporin转化生长因子-β   D-重复序列   骨关节疾病  

摘要： Asporin基因是一种细胞外基质蛋白,属于富含亮氨酸重复序列的小分子蛋白多糖家族。近年生物遗传学研究证实Asporin基因可通过与生长因子相互作用而影响骨与软骨的形成与分化,与骨关节炎、类风湿关节炎及腰椎间盘退变等骨关节疾病相关。该文就Asporin基因的结构、表达、与生长因子的相互作用及与骨关节疾病的相关性等作一综述。

关键词： 椎间盘退变   基因治疗   Sox9   生物学机制   分子生物学   治疗方法   卧床休息   手术治疗  

摘要： 随着分子生物学的发展和对椎间盘退变的生物学机制的深入研究,人们已经越来越不满足于传统的椎间盘退变治疗方法,如卧床休息、理疗、药物治疗和手术治疗等.这些传统方法仅能短期缓解椎间盘退变给患者带来的痛苦,并不能从根本上终止退变进程.

关键词： Nucleus Pulposus   Disc Degeneration   Nucleus Pulposus Cell   Disc Tissue   Outer Annulus  

摘要： Introduction Asporin, also known as periodontal ligament-associated protein 1 (PLAP1), is a member of the family of small leucine-rich proteoglycan (SLRP) family. It is present within the cartilage extracellular matrix (ECM), and is reported to have a genetic association with osteoarthritis. Its D14 allele has recently been found to be associated with lumbar disc degeneration in Asian subjects. There have been no studies, however, of this gene's normal immunohistochemical localization within the human intervertebral disc, or of expression levels in Caucasian individuals with disc degeneration. Methods Studies were approved by our human subjects Institutional Review Board. Methods included immunohistochemical localization of asporin in the disc of humans and the sand rat (a small rodent with spontaneous age-related disc degeneration), and Affymetrix microarray analysis of asporin gene expression in vivo and in vitro. Results Immunohistochemical studies of human discs revealed that some, but not all, cells of the outer annulus expressed asporin. Fewer cells in the inner annulus contained asporin, and it was rarely present in cells in the nucleus pulposus. Similar patterns were found for the presence of asporin in lumbar discs of sand rats. Substantial relative gene expression levels were seen for asporin in both disc tissue and in annulus cells grown in three-dimensional culture. More degenerate human discs (Thompson grade 4) showed higher expression levels of asporin than did less degenerate (grade 1, 2 and 3) discs, P = 0.004. Conclusions In the discs of Caucasian subjects studied here, and in the sand rat, greater immunolocalization levels were found in the outer compared to inner annulus. Localization was rare in the nucleus. Gene expression studies showed greatest expression of asporin in the more degenerate human discs in vivo.

关键词： Asporin   Ⅱ型胶原   聚集蛋白多糖   突出   脱出  

摘要： 目的 腰椎间盘退变(lumbar disc degeneration,LDD)是引起腰背痛的主要原因。在全球大约有80%的人在其一生中都经历过腰背疼,腰背痛给人们带来巨大的痛苦,高额的医疗费用以及对社会经济产生显著的影响,尤其是工作时间的丧失给社会来了严重的医疗和经济负担。椎间盘退变(intervertebral disc degene ration,ⅣDD)是一系列脊柱退行性疾病的根本病理基础,其结局往往是椎管狭窄、脊柱节段不稳、骨赘形成、腰腿疼、颈椎病、椎间盘突出及随之而来的神经根、脊髓受压等等,临床发病广,病情复杂。以腰椎间盘突出症最具有代表性。因此,对腰间盘突出及退变的发生机制的研究显得尤为重要。 Asporin蛋白于2001年在关节软骨和半月板中被发现,根据其分子结构的特点被划分为小的富含亮氨酸蛋白多糖(SLRP)家族的新成员,该蛋白家族的成员按着氨基酸序列和基因组成的特点被划分为四组,Asporin蛋白同Decoin蛋白和Biglycan蛋白一起共同被划在第一组。研究发现该蛋白在骨关节炎的关节软骨中大量表达,故认为其与骨性关节炎密切相关。 OA和LDD都是骨关节退变性疾病,表达在关节软骨的许多基因同时在椎间盘同样也有表达,所以我们推测ASPN对于LDD来说也应是一个易患性基因。因此本实验旨在研究asporin蛋白与在突出腰椎间盘中的表达。 材料和方法 1、标本的采集 取自中国医科大学附属第一临床医院骨科2008年3月至2008年11月腰椎间盘突出症手术取出的髓核标本25例,年龄26-76岁,其中男12例,女13例,依据国际腰椎研究学会的分类标准分为突出和脱出,其中突出12例(突出组),脱出13例(脱出组)。标本取出后,将髓核和纤维环组织分离,取髓核组织保存于-70℃冰箱。对照组5例取自腰椎骨折行前路手术取出间盘的患者,年龄21-45岁,男3例,女2例,间盘均无退变迹象,纤维环完整,纤维环与髓核分界清晰(正常对照组)。 2、方法 采用蛋白印记(western blot)方法检测asporin蛋白在25例退变间盘髓核组织,5例正常间盘组织中的表达。 3、结果判定 电脑成像灰度值测定,通过比较各样本蛋白及内参照β-actin的光密度值,将结果进行半定量分析(即将组织样本中的蛋白与组织中恒定表达的β-actin蛋白的灰度值进行比较),最终得出待测蛋白在退变间盘和正常间盘组织中的相对含量。 4、统计学处理 所有数据资料均采用SPSS13.0软件进行统计处理,各组计量资料的结果采用方差分析,P＜0.05有统计学意义。 结果 1、正常间盘和退变间盘组织中Ⅱ型胶原的表达 Ⅱ型胶原在正常间盘组织中的表达分别是突出组的1.4倍和脱出组的1.6倍,均有显著性差异(P＜0.01);Ⅱ型胶原突出组表达是脱出组的1.1倍,无显著性差异(P=0.07)。 2、正常间盘和退变间盘组织中聚集蛋白聚糖的表达 聚集蛋白多糖在正常间盘组织中的表达是突出组的1.0倍,没有显著性差异(P=0.06);是脱出组的1.5倍,有显著性差异(P＜0.01);聚集蛋白多糖突出组中的表达是脱出组的1.4倍,有显著性差异(P＜0.01)。 3、正常间盘和退变间盘组织中asporin蛋白的表达 Asporin蛋白在脱出组中的表达是突出组的1.2倍,无显著性差异(P=0.06);是正常组的1.5倍有显著性差异(P＜0.01);突出组是正常组的1.3倍,有显著性差异(P＜0.05)。 结论 1、Asporin蛋白在人正常和突出间盘中均有表达。 2、Asporin蛋白在突出间盘中的表达显著增加。

关键词： 椎间盘/病理学   基因疗法   模型   动物   组织构建  

摘要： 随着人类对椎间盘退行性变疾病更深入的认识和分子生物学技术的研究进展及其在临床上的应用,在椎间盘退行性变时,早期进行生物学的干预,对延缓椎间盘退行性变甚至逆转疾病进程产生了可能。椎间盘退行性变疾病的基因治疗研究涉及到动物模型的选取、基因载体的选择、目的基因的应用等。构建类似人体的动物模型、选择合适的基因载体和应用理想的目的基因是疾病基因治疗的关键。基因治疗必须在证实其有效性并确保患者的安全的基础上应用于临床,故目前还有许多问题有待于解决。

关键词： Osteoarthritis   Asporin   Genetics   Polymorphism   Hand   Knee  

摘要： Objective: An association between osteoarthritis (OA) and functional polymorphisms in the aspartic acid (D) repeat of the asporin (ASPN) gene was reported in Japanese and Han Chinese populations. The aim of this study was to assess the association of variants in the ASPN gene with the presence of radiographic hand and/or knee CA in a US Caucasian population. Methods: Ten single nucleotide polymorphisms (SNPs) within the ASPN gene were genotyped in 775 affected siblings with radiographically confirmed hand and/or knee OA, and the allelic, genotypic and haplotypic association results were examined. Results: One variant (SNP RS7033979) showed nominal evidence of association with both hand CA (P - 0.042) and knee CA (P - 0.032). Four additional SNPs showed nominal evidence of association with knee CA only. These associations were only observed with genotypic tests;the corresponding allelic and haplotype tests did not corroborate the single-point association results. Conclusion: These data suggest that polymorphisms within ASPN are not a major influence in susceptibility to hand or knee OA in US Caucasians. (C) 2008 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

关键词： microarray   heart valve maturation   asporin   osteoglycin   Twist1   collagen  

摘要： Chakraborty S, Cheek J, Sakthivel B, Aronow BJ, Yutzey KE. Shared gene expression profiles in developing heart valves and osteoblast progenitor cells. Physiol Genomics 35: 75-85, 2008. First published July 8, 2008;doi: 10.1152/physiolgenomics.90212.2008.-The atrioventricular (AV) valves of the heart develop from undifferentiated mesenchymal endocardial cushions, which later mature into stratified valves with diversified extracellular matrix (ECM). Because the mature valves express genes associated with osteogenesis and exhibit disease-associated calcification, we hypothesized the existence of shared regulatory pathways active in developing AV valves and in bone progenitor cells. To define gene regulatory programs of valvulogenesis relative to osteoblast progenitors, we undertook Affymetrix gene expression profiling analysis of murine embryonic day (E)12.5 AV endocardial cushions compared with E17.5 AV valves (mitral and tricuspid) and with preosteoblast MC3T3-E1 (subclone4) cells. Overall, MC3T3 cells were significantly more similar to E17.5 valves than to E12.5 cushions, supporting the hypothesis that valve maturation involves the expression of many genes also expressed in osteoblasts. Several transcription factors characteristic of mesenchymal and osteoblast precursor cells, including Twist1, are predominant in E12.5 cushion. Valve maturation is characterized by differential regulation of matrix metalloproteinases and their inhibitors as well as complex collagen gene expression. Among the most highly enriched genes during valvulogenesis were members of the small leucine-rich proteoglycan (SLRP) family including Asporin, a known negative regulator of osteoblast differentiation and mineralization. Together, these data support shared gene expression profiles of the developing valves and osteoblast bone precursor cells in normal valve development and homeostasis with potential functions in calcific valve disease.

关键词： LMP-1基因   椎间盘退变   基因治疗  

摘要： 细胞内信号转导分子LIM矿化蛋白-1(LMP-1)基因是近年证实与椎间盘退变相关的基因之一,其表达产物为一种细胞内非分泌性骨诱导蛋白。它可通过调节各种细胞因子的生成和其他相关基因的表达,来实现其所诱导的透明样基质的合成增加。研究证明LMP-1基因在椎间盘细胞过度表达,以及通过骨形态发生蛋白介导机制,在体内外条件下均可增加蛋白聚糖、硫酸氨基葡聚糖及Ⅱ型胶原的合成,从而减缓甚至逆转椎间盘细胞的退化。

关键词： PLAP-1   asporin   SLRP   BMP-2   Smad   leucine-rich repeat  

摘要： We previously identified the novel gene, periodontal ligament-associated protein-1 (PLAP-1)/asporin and reported that PLAP-1/asporin inhibited bone morphogenetic protein-2 (BMP-2)-induced cytodifferentiation of periodontal ligament (PDL) cells probably by direct interaction with BMP-2. Here, we elucidated the detailed regulatory mechanism of this protein on BMP-2-induced cytodifferentiation of PDL cells. Recombinant PLAP-1 /asporin inhibited BMP-2-induced cytodifferentiation of PDL cells and competitively prevented BMP-2 from binding to the BMP receptor-IB (BMPR-IB), resulting in inhibition of BMP-dependent activation of Smad proteins. The induction of mutation to the leucine-rich repeat (LRR) motif, especially LRR5, within PLAP-1 /asporin rescued the inhibitory effect of PLAP-I /asporin on BMP-2. By contrast, a 26-amino acid peptide in the PLAP-1/asporin LRR5 sequence inhibited BMP-2 activity. Our findings indicate that PLAP-1 /asporin inhibits BMP-2-induced differentiation of PDL cells resulting from inactivation of the BMP-2 signaling pathway and that LRR, especially LRR5 of PLAP-1 /asporin, plays an important role in the PLAP-1/asporin-BMP-2 interaction. (C) 2008 Elsevier Inc. All rights reserved.