关键词： Proteins  

摘要： Osteoarthritis ( OA), the most prevalent form of skeletal disease, represents a leading cause of disability following middle age. OA is characterized by the loss of articular cartilage;however, the details of its etiology and pathogenesis remain unclear. Recently, we demonstrated a genetic association between the cartilage extracellular matrix protein asporin and OA ( Kizawa, H., Kou, I., Iida, A., Sudo, A., Miyamoto, Y., Fukuda, A., Mabuchi, A., Kotani, A., Kawakami, A., Yamamoto, S., Uchida, A., Nakamura, K., Notoya, K., Nakamura, Y., and Ikegawa, S. ( 2005) Nat. Genet. 37, 138-144). Furthermore, we showed that asporin binds to transforming growth factor-beta (TGF-beta), a key cytokine in OA pathogenesis, and inhibits TGF-beta-induced chondrogenesis. To date, functional data for asporin have come primarily from mouse cell culture models of developing cartilage rather than from human articular cartilage cells, in which OA occurs. Here, we describe mechanisms for asporin function and regulation in human articular cartilage. Asporin blocks chondrogenesis and inhibits TGF-beta 1-induced expression of matrix genes and the resulting chondrocyte phenotypes. Small interfering RNA-mediated knockdown of asporin increases the expression of cartilage marker genes and TGF-beta 1;in turn, TGF-beta 1 stimulates asporin expression in articular cartilage cells, suggesting that asporin and TGF-beta 1 form a regulatory feedback loop. Asporin inhibits TGF-beta/Smad signaling upstream of TGF-beta type I receptor activation in vivo by co-localizing with TGF-beta 1 on the cell surface and blocking its interaction with the TGF-beta type II receptor. Our results provide a basis for elucidating the role of asporin in the molecular pathogenesis of OA.

关键词： 椎间盘退变   基因治疗   脊柱退变性疾病   疾病过程   椎间盘突出   神经根病变   disc   脊柱不稳  

摘要： 椎间盘退变(intervertebral disc degeneration,IDD)可以引起一系列脊柱退变性疾病如椎间盘突出、脊柱不稳、神经根病变和脊髓病变等,目前的治疗方法主要是手术治疗,但手术方法只是处理终末期的症状,不能逆转疾病过程本身.因此国内外学者们一直致力于寻找一种能逆转这个疾病过程的方法,近来对椎间盘的生化构成及其内环境的进一步了解以及某些基因被发现对椎间盘内基质合成和分解有着重要的影响,这些为科学家寻求逆转这个疾病过程提供了新方法.为此,在过去几年里很多关注的焦点都集中在基因治疗上,并取得了预期效果.现就其研究近况综述如下.

关键词： asporin   FIRM   GDF5   genome-wide association study   osteoarthritis  

摘要： Purpose of review Osteoarthritis is a serious medical, social and economic problem affecting populations worldwide. Identifying susceptibility genes for osteoarthritis is a critical step in tackling this disease. The association study is today's most powerful tool for finding such genes, and the osteoarthritis research community has enjoyed initial success through the identification of several promising candidates. This review summarizes recent advances and emerging challenges in osteoarthritis association studies. Recent findings Replication studies have confirmed association of functional sequence variations in the secreted frizzled-related protein 3 (FRZB) and asporin (ASPN) genes with osteoarthritis. These studies have also prompted discussion of population-specific differences in reported associations. Association of several other promising genes with osteoarthritis, including LRCH1, RHOB, TXNDC3 and GDF5, await replication. The Human Genome Project and the International HapMap Project have established an infrastructure to support genome-wide association studies. Large-scale case-control association scans are underway, and genome-wide association scans are also beginning. Summary Due to initial success in confirming several susceptibility genes and the advent of the post-genome sequence era, this area of osteoarthritis study is expanding quickly. To overcome current challenges and to move on to the next stage, however, international collaboration based on a common platform is essential.

关键词： Ligaments  

摘要： Periodontal ligament-associated protein-1 (PLAP-1)/asporin is a recently identified novel member of the small leucine-rich repeat proteoglycan family. PLAP-1/asporin is involved in chondrogenesis, and its involvement in the pathogenesis of osteoarthritis has been suggested. We report that PLAP-1/asporin is also expressed specifically and predominantly in the periodontal ligament (PDL) and that it negatively regulates the mineralization of PDL cells. In situ hybridization analysis revealed that PLAP-1/asporin was expressed specifically not only in the PDL of an erupted tooth but also in the dental follicle, which is the progenitor tissue of the PDL during tooth development. Overexpression of PLAP-1/asporin in mouse PDL-derived clone cells interfered with both naturally and bone morphogenetic protein 2 (BMP-2)-induced mineralization of the PDL cells. On the other hand, knockdown of PLAP-1/asporin transcript levels by RNA interference enhanced BMP-2-induced differentiation of PDL cells. Furthermore co-immuno-precipitation assays showed a direct interaction between PLAP1/asporin and BMP- 2 in vitro, and immunohistochemistry staining revealed the co-localization of PLAP-1/asporin and BMP- 2 at the cellular level. These results suggest that PLAP-1/asporin plays a specific role(s) in the periodontal ligament as a negative regulator of cytodifferentiation and mineralization probably by regulating BMP- 2 activity to prevent the periodontal ligament from developing non-physiological mineralization such as ankylosis.

关键词： asporin   association   knee osteoarthritis   age at onset   Han Chinese  

摘要： Recent genetic studies for osteoarthritis (OA) have been focused on ASPN, the gene encoding asporin, where aspartic acid (D)-repeat polymorphisms are associated with OA in several ethnic groups. The purpose of the present study is to further examine the association of the D-repeat polymorphism in a Han Chinese population. The D-repeat polymorphism was genotyped in 354 knee OA patients (257 women and 97 men) who suffered from primary symptomatic knee OA with radiographic confirmation, and the association of the repeat with various clinical parameters was examined. The age at onset (years) in patients with the D14 allele (mean: 51.9, SD: 8.5) was younger than that those without the D14 allele (mean: 54.9, SD: 10.9) (P = 0.023). Survival analysis showed D14 was significantly associated with age at onset of OA (P = 0.004 in the dominant model). The average age at onset of patients with the D13/D13 genotype (mean: 56.1, SD: 11.1) was older than those without the D13/D13 genotype (mean: 53.0, SD: 9.9) (P = 0.013). Our study further highlighted the significance of asporin in OA.

关键词： 人类椎间盘退变   分子生物学机制   治疗前   非类固醇抗炎药   基因   脊柱长度   椎体连接   尸体标本  

摘要： 人类的脊柱由23个椎间盘将椎体连接在一起，从颈椎到腰椎，椎间盘约占脊柱长度的20％～30％，其有着使脊柱具有活动性及缓冲各向应力的作用。人类椎间盘退变从20岁开始，在尸体标本上，在49岁时，大约有97％的椎间盘已经退变或有退变迹象。目前对椎间盘退变所引起的疾病主要的治疗观点是：（1）保守治疗，应用非类固醇抗炎药（NSAIDs）等控制炎症反应；

摘要： Background: Asporin belongs to a family of proteins associated with the cartilage matrix. Objective: To investigate the role of the functional polymorphism consisting of an aspartic acid (D) repeat polymorphism located in the ASPN gene in the susceptibility to and clinical outcome of rheumatoid arthritis. Methods: A total of 803 Spanish Caucasian patients with rheumatoid arthritis and 904 controls of the same ethnic origin and matched for age and sex were included in the study. The asporin D repeat polymorphism was genotyped using polymerase chain reaction with a fluorescent primer. Results: No significant differences were detected in the distribution of the 10 alleles found in our population on comparing patients with rheumatoid arthritis with control groups. Nevertheless, individuals bearing D14 produced rheumatoid factor more often than the rest (85.7% v 72.1%, p = 0.006, odds ratio (OR) = 2.35, 95% confidence interval 1.21 to 4.50), and the mean (SD) onset age was higher in the group of individuals bearing D13 (50.09 (13.94)) compared with the rest (47.21 (14.31)), although the difference did not reach significance (p = 0.06). Conclusion: The results do not support a major role for asporin D repeat polymorphism in the susceptibility to rheumatoid arthritis. Nevertheless, they support the influence of this gene on the outcome of the disease.

关键词： 椎间盘   动物模型   腺相关病毒   转化生长因子β1   血管内皮生长因子   转染   基因治疗  

摘要： 目的：建立羊椎间盘退变模型；应用腺相关病毒（adeno-associated virus，AAV）介导人转化生长因子β1（human transforming growth factor-β1，hTGF-β1）和人血管内皮生长因子（human vascular endothelial growth factor，hVEGF）基因体内转染羊退变椎间盘，观察AAV-hTGF-β1和hVEGF的表达以及单基因转染和双基因联合转染对退变椎间盘的生物学作用。 方法：成年SPF（specific pathogen free，SPF）级去势山羊，通过11号刀片损伤椎间盘前外侧纤维环的方法建立椎间盘退变模型，造模后4、8、12、24周分别进行影像学和组织学检测，观察造模椎间盘变化。将造模成功动物随机分为A、B、C、D和E5组，各组分别于造模椎间盘内注射50μL试剂：A组rAAV2-hTGFβ1、B组rAAV2-hVEGF、C组rAAV2-hTGFβ1+rAAV2-hVEGF、D组磷酸盐缓冲液（PBS）、E组rAAV2-EGFP（enhanced green fluorescent protein，EGFP）。转染后2、4、8、12周时分别进行影像学、组织学和生物化学检测。 结果：（1）影像学和组织学检测结果表明造模动物椎间盘发生缓慢、可靠的退行性变。（2）基因转染后椎间盘的变化①影像学检测：A组、C组动物椎间盘高度指数（disc heigllt index，DHI）均高于D组，C组更显著，差别有统计学意义；B组与D组无显著性差异。②组织学检测：HE、Safranine 0染色后观察到A组、C组动物椎间盘细胞数目减少量、结构紊乱程度、髓核纤维环界限模糊程度等均低于D组。B组与D组无显著性差异。免疫组化染色后观察到：A组、C组动物椎间盘髓核中Ⅱ胶原含量下降程度、纤维环中Ⅰ胶原含量下降程度均低于D组，C组更显著，差别有统计学意义，B组与D组无显著性差异；转染两周后，A组、B组和C组的rAAV2-hTGFβ1、rAAV2-hVEGF和rAAV2-hTGFβ1+rAAV2-hVEGF较D组显著增多；E组动物转染后12周仍可观察到EGFP的表达。③生物化学检测：A组、C组动物椎间盘Ⅰ、Ⅱ型胶原和蛋白多糖的含量下降程度均低于D组，C组更显著，差别有统计学意义；B组与D组无显著性差异。 结论：（1）本方法可以成功建立一种椎间盘退变动物模型；（2）rAAV2-hTGFβ1和rAAV2-hVEGF转染退变的椎间盘后，可持续表达12周；（3）hTGFβ1转染可在一定程度上逆转椎间盘退变；（4）hVEGF可协同hTGFβ1逆转椎间盘退变；（5）hTGFβ1和hVEGF共转染具有协同效应。

关键词： 骨髓间充质干细胞   骨形态发生蛋白   基因治疗   椎间盘退变   体内研究  

摘要： 目的:构建含有人类重组骨形态发生蛋白- 7(bone morphogenetic protein-7 , BMP-7 )基因腺病毒载体,转染兔骨髓间充质干细胞(bone mesenchymal stem cell,BMSC),将其导入椎间盘内,观察对兔退变椎间盘的影响。方法:构建hBMP-7腺病毒载体,将其感染体外培养的兔BMSC,免疫细胞化学的方法观察hBMP-7基因在细胞内的表达情况;采用髓核抽吸法建立兔椎间盘退变动物模型,分为3组:退变对照组、BMSC治疗组、基因转染BMSC治疗组。3月后应用RT-PCR、免疫组化和蛋白质免疫印迹分析检测hBMP-7在体内的表达情况;应用核磁共振、病理形态学检测和生化分析的方法,观察椎间盘退变的修复效果。结果:与退变对照组相比,BMSC治疗组和基因转染BMSC治疗组经MRI测量的椎间盘高度和T2信号强度,免疫组化和生化分析检测的Ⅱ型胶原、蛋白多糖含量均明显增高,以基因转染BMSC治疗组尤甚(P<0.05)。hBMP-7的mRNA和蛋白水平均随治疗效果的好转而升高。结论:骨形态发生蛋白-7可促进骨髓间充质干细胞修复椎间盘退变的能力,为进一步实验提供了依据。

关键词： BMP-4   椎间盘退变   重组腺病毒   髓核   蛋白多糖   定量分析   动物模型   基因治疗  

摘要： 本研究用AdEasy方法构建了BMP-4基因的重组腺病毒载体;成功的进行了人退变髓核细胞的原代培养;在人退变椎间盘细胞离体实验中证实了BMP-4基因可以在退变髓核细胞或组织中持续大量表达,并刺激椎间盘基质蛋白多糖和Ⅱ型胶原的产生,为基因治疗椎间盘退变开辟了新的路径;在椎间盘退变动物模型中定量分析了BMP-4基因治疗对椎间盘基质合成的影响,为椎间盘退变的发病机制研究提出了新的思考。