SDF-1/CXCR4信号通路在骨性关节炎病理进程中的作用

背景：骨性关节炎的发病机制错综复杂,其预防与治疗是当今医学界的难题之一,与其相关的信号通路的研究已成为国内外研究的热点,其靶向治疗有望成为攻克骨性关节炎的关键。 目的：总结SDF-1/CXCR4信号通路在诸多疾病尤其是在骨性关节炎发病中的作用,为骨性关节炎的靶向治疗提供科学依据。 方法：应用计算机检索PubMed和CBM数据库中2008-09/2010-07发表的相关文献。以主题检索为主要检索方法,结合限定检索等方法,以“SDF-1/CXCR4信号通路、骨性关节炎”和“SDF-1/CXC4 signaling pathway, osteoarthritis”为中英文检索词,选择与骨性关节炎SDF-1/CXCR4信号通路有关的文献,排除内容陈旧、重复的文章。 结果与结论：共检索到2 147篇文章,按纳入和排除标准对文献进行筛选,保留32篇文章进行综述。目前,SDF-1/CXCR4信号通路在诸多疾病的发生发展过程中具有重要作用,已成为目前世界医学的研究热点之一。有研究表明,SDF-1/CXCR4信号通路可能在骨性关节炎的发病中具有重要作用,而对该信号通路的干预可能成为预防与治疗骨性关节炎的靶点,有望成为今后骨性关节炎防治方面研究的热点。     

Limbal epithelial stem/progenitor cells attract stromal niche cells by SDF-1/CXCR4 signaling to prevent differentiation

Corneal epithelial stem cells (SCs) are an ideal model for investigating how adult lineage-committed epithelial SCs are regulated by an anatomically defined and accessible niche, that is, limbal palisades of Vogt, located between the cornea and the conjunctiva. We have used collagenase digestion to isolate the entire limbal epithelial SCs and subjacent mesenchymal cells, and we have demonstrated that their close association is crucial for promoting epithelial clonal growth, implying that the latter serves as niche cells (NCs). After their close association was disrupted by trypsin/EDTA, single SCs and NCs could reunite to generate sphere growth in three-dimensional Matrigel in the embryonic SC medium, and that such sphere growth initiated by SC-NC reunion was mediated by SDF-1 uniquely expressed by limbal epithelial progenitor cells and its receptor CXCR4, but not CXCR7, strongly expressed by limbal stromal NCs. Inhibition of CXCR4 by AMD3100 or a blocking antibody to CXCR4 but not CXCR7 disrupted their reunion and yielded separate spheres with a reduced size, while resultant epithelial spheres exhibited more corneal differentiation and a notable loss of holoclones. For the first time, these results provide strong evidence supporting that limbal SC function depends on close physical association with their native NCs via SDF-1/CXCR4 signaling. This novel in vitro model of sphere growth with NCs can be used for investigating how limbal SC self-renewal and fate decision might be regulated in the limbal niche.     

DHA对糖尿病认知障碍大鼠海马神经元SDF-1/CXCR4通路的影响

目的:研究DHA对糖尿病认知障碍大鼠空间学习记忆的作用,探讨DHA对糖尿病大鼠海马神经元SDF-1/CXCR4表达的影响。方法:采用SD大鼠,随机分为对照组、对照+DHA组、糖尿病组和糖尿病+DHA组,以高脂膳食加小剂量链脲佐菌素诱发大鼠糖尿病。Morris水迷宫检测大鼠空间学习记忆能力,ELISA法、PCR法检测海马神经元SDF-1、TNF-α含量,免疫组化法检测CXCR4受体表达情况,Western Blot法检测海马神经元JNK磷酸化水平。结果:DHA可在一定程度上改善糖尿病大鼠学习记忆能力。糖尿病大鼠海马神经元TNF-α和p-JNK水平升高,SDF-1水平明显降低,CXCR4受体阳性神经元数量明显减少。DHA抑制TNF-α和JNK磷酸化,增加CXCR4的表达,升高SDF-1的含量。结论:DHA可减轻糖尿病大鼠的认知损伤,其机制可能与提高SDF-1水平,抑制海马神经元JNK磷酸化,降低炎性因子水平有关。     

SDF-1/CXCR4生物学轴与肿瘤关系的研究进展

趋化因子SDF-1,又称CXCL12,PBSF,与其特异性受体CXCR4广泛表达在多种组织和器官上,它们所构成的SDF-1/CXCR4 生物学轴在多种肿瘤的发生,发展以及转移中都发挥重要作用,其可能是通过MAPK,AKT通路发挥作用。对这一特殊生物学轴的研究可能为肿瘤防治找到新的突破口。     

sdf-1及其受体在成体干细胞迁移中的作用

基质细胞衍生因子是一种干细胞趋化因子,它可以通过与其受体CXCR4结合,调控干细胞定向迁移,发挥特定的生物学效应.SDF-1/CXCR4轴在调控骨髓造血干细胞归巢、调节干/前体细胞定向迁移至靶器官促进受损组织器官再生的病理生理过程中发挥着重要的作用.本文就SDF-1/CXCR4轴在成体干细胞迁移中的作用作简要综述.     

电针结合康复训练通过SDF-1/CXCR4信号通路对癫痫大鼠的保护机制研究

目的 探讨电针结合康复训练通过SDF-1/CXCR4信号通路对癫痫大鼠的保护机制.方法 70只雄性SD大鼠随机分为对照组(n=10)、模型组(n=30)、治疗组(n=20)与中和组(n=10),采用氯化锂联合戊四氮致构建癫痫大鼠模型,观察癫痫大鼠认知功能、癫痫发作频次、持续时间;TUNEL方法检测癫痫大鼠海马区凋亡程度...     

SDF-1/CXCR4增强骨髓间质干细胞的造血支持作用

目的探讨基质细胞衍生因子-1(SDF-1)/CXCR4在骨髓间质干细胞(MSCs)支持CD34 造血干/祖细胞(HSPCs)扩增中的作用。方法在长期培养基(LTC)中,以大鼠骨髓MSCs作为饲养层体外扩增骨髓CD34 细胞,每周分别加入SDF-1、SDF-1抗体或CXCR4抗体至5周。计算CD34 细胞数和集落形成细胞(CFC)数,以评价造血支持功能。为评估SDF-1/CXCR4对CD34 细胞增殖周期的影响,进行了杀伤试验以计算增殖指数。流式细胞术检测MSCs和CD34 细胞中SDF-1与CXCR4的表达;ELISA检测MSCs和CD34 细胞培养基中SDF-1的含量。结果CD34 细胞数、CFC数和增殖指数在加入SDF-1后明显增加(P<0.01),加入SDF-1抗体或CXCR4抗体后明显减少(分别为P<0.05,P<0.01)。CD34 细胞表面表达CXCR4,MSCs则不表达;MSCs细胞内表达SDF-1,而CD34 细胞不表达。在MSCs培养基中检测到SDF-1,在CD34 细胞培养基中未发现。结论SDF-1/CXCR4在骨髓MSCs支持HSPCs扩增中起重要作用。     

圣愈汤对胶原诱导性关节炎小鼠踝关节组织SDF-1/CXCR4信号通路的影响

目的 探讨圣愈汤对胶原诱导性关节炎(CIA)小鼠的治疗作用,及对基质细胞衍生因子1(SDF-1)/趋化因子受体4(CXCR4)信号轴的调控作用.方法 取DAB/1小鼠72只,用随机数字表法分为正常对照组、模型组、阳性对照组(甲氨蝶呤,0.1 mg/kg)组和低(9g/kg)、中(18 g/kg)、高(36 g/kg)剂...     

白藜芦醇对新生大鼠神经元缺血缺氧时SDF-1/CXCR4通路抗凋亡作用的调控机制

目的:探究白藜芦醇(RSV)对缺血缺氧诱导的新生大鼠脑神经元凋亡及基质细胞衍生因子1(SDF-1)/CXC趋化因子受体4(CXCR4)通路的作用和机制。方法:体外培养新生大鼠皮质神经元,给予氧糖剥夺(OGD)模拟新生儿缺血缺氧性脑病(HIE)模型。首先将细胞随机分成4组:对照(control)组、HIE组、HIE+RSV低剂量(10μmol/L)组和HIE+RSV高剂量(50μmol/L)组。OGD处理2 h后加入相应剂量的RSV继续培养24 h,通过流式细胞术检测细胞凋亡,Western blot检测凋亡相关蛋白及SDF-1和CXCR4的蛋白表达水平,real-time PCR检测SDF-1和CXCR4的mRNA表达水平。然后使用CXCR4抑制剂AMD3100与RSV共同处理OGO损伤的细胞24h,检测SDF-1/CXCR4通路阻断后RSV对细胞凋亡和凋亡相关蛋白表达水平的影响。结果:RSV能够抑制OGD诱导的神经元凋亡,下调活化的caspase-3和细胞色素C的水平,上调Bcl-2/Bax比值(P0.05)。与对照组相比,OGD导致SDF-1和CXCR4表达增加;与模型组相比,RSV能够上调SDF-1和CXCR4的表达(P0.05);使用AMD3100阻断SDF-1/CXCR4通路减弱了RSV抑制OGD诱导的细胞凋亡的作用。结论:RSV可抑制缺血缺氧诱导的新生大鼠神经元凋亡,其机制可能是通过上调SDF-1/CXCR4通路发挥作用的。     

VEGFR1/CXCR4-positive progenitor cells modulate local inflammation and augment tissue perfusion by a SDF-1-dependent mechanism

Recruitment and retention of circulating progenitor cells at the site of injured or ischemic tissues facilitates adult neo-vascularization. We hypothesized that cell therapy could modulate local neo-vascularization through the vascular endothelial growth factor (VEGF)/stromal cell-derived factor-1 (SDF-1) axis and by paracrine effects on local endothelial cells. We isolated from rat bone marrow a subset of multipotent adult progenitor cell-derived progenitor cells (MDPC). In vitro, MDPCs secreted multiple cytokines related to inflammation and angiogenesis, including monocyte chemotactic protein-1, SDF-1, basic fibroblast growth factor, and VEGF, and expressed the chemokine receptors CXCR4 and VEGFR1. To investigate in vivo properties, we transplanted MDPCs into the ischemic hind limbs of rats. Elevated levels of the chemokine SDF-1 and colocalization of CD11b⁺ cells marked the initial phase of tissue remodeling after cell transplantation. Prolonged engraftment was observed in the adventitial–medial border region of arterioles of ischemic muscles. However, engrafted cells did not differentiate into endothelial or smooth muscle cells. Limb perfusion normalized 4 weeks after cell injection. Inhibition of SDF-1 reduced the engraftment of transplanted cells and decreased endothelial cell proliferation. These findings suggest a two-stage model whereby transplanted MDPCs modulate wound repair through recruitment of inflammatory cells to ischemic tissue. This is an important potential mechanism for cell transplantation, in addition to the direct modulation of local vascular cells through paracrine mechanisms.     

SDF-1/CXCR4轴活化诱导内皮祖细胞增殖、迁移及管型形成

目的观察趋化因子SDF-1促内皮祖细胞增殖、迁移和管型形成的作用。方法用免疫细胞化学检测内皮祖细胞SDF-1和CXCR4表达;用MTT法、Millicell趋化法及Matrigel体外三维成型法分别检测不同浓度的趋化因子SDF-1促内皮祖细胞增殖、迁移和管型形成。并应用CXCR4受体抑制剂AMD3100观察上述指标的变化。结果免疫细胞化学显示内皮祖细胞表达SDF-1和CXCR4蛋白。SDF-1可促进内皮祖细胞的增殖、迁移和体外小管样结构的形成。AMD3100可抑制SDF-1的诱导作用。结论SDF-1/CXCR4轴在内皮祖细胞参与血管新生中可能发挥重要作用。     

Effects of SDF-1/CXCR4 on Acute Lung Injury Induced by Cardiopulmonary Bypass

Acute lung injury (ALI) is one of the most important complications after cardiopulmonary bypass (CPB) and the complex pathophysiology remains to be resolved incomplete. SDF-1/CXCR4 chemokine axis can chemotactically accumulate inflammatory cell to local tissue and regulate the release of inflammatory factors, and SDF-1 has a strong chemotaxis effect on neutrophils with CXCR4. Since CPB animal model was difficult to establish, there was still no report about the effect of SDF-1/CXCR4 on neutrophil chemotaxis in ALI after CPB. Here, a stable CPB rat model was constructed to clarify the role of SDF-1/CXCR4 axis in the CPB-induced ALI. Real-time quantitative PCR (RT-qPCR), Western blot analysis, and enzyme-linked immunosorbent assay (ELISA) were used to detect the changes of SDF-1 and CXCR4 in lung tissues, blood, bronchoalveolar lavage (BALF), and/or isolated neutrophils. SDF-1/CXCR4 was increased after CPB, both of that were increased in blood; CXCR4 was increased in neutrophils; SDF-1/CXCR4 was also increased in BALF of CPB model. Results indicated that SDF-1/CXCR4 axis played a key role in the process of early ALI after CPB, also showed that lung injury was significantly reduce after blocking SDF-1/CXCR4 axis, suggest that CXCR4 might be a new target for ALI treatment.     

SDF-1/CXCR4对缺血性卒中后神经发生的调节作用研究进展

脑缺血损伤后表达增高的基质细胞来源因子-1(SDF-1)和C-X-C趋化因子受体4(CXCR4)可以调控内源性神经干细胞增殖、分化和迁移。     

Phenotypic Knockout of CXCR4 on Molt-4 with SDF-1α/54 Attached with KDEL

Objective :To investigate the mechanism of phenotypic knockout of CXCR4 on T-cell leukemia cell line Molt-4 via SDF-1α/54/KDEL intrakine technology, which the mutant SDF-1α/54, human stromal cell-derived Faceor-1 (SDF-1α) was deleted its Cterminal α-helix and attached with a endoplasimc reticulum retention signal 4-peptide-KDEL encoding gene, so that retain the newly synthesized receptor CXCR4 within the Molt-4 cells endoplasmic reticulum. Methods: The recombinant vector pEGFP-C3/SDF-1α/54/KDEL were transfected into Cos-7 cells by liposome, SDF-1α/54/KDEL fusion protein was confirmed with western blot. The recombinant plasmids were transfected transiently into Molt-4 by electroporation. Results:Western blot confirmed SDF-1α/54/KDEL expression in Cos-7. A dramatic downregulation of CXCR4 expression on Molt-4 was demonstrated by flow cytometric (FCM) analysis. Conclusion:SDF-1α/54/KDEL and SDF-1αKDEL have no significant deviation for phenotypic knockout of CXCR4. These suggest that the phenotypic knockout effects of SDF-1α/54 against CXCR4 are not influenced by deleting of SDF-1α helix in the C-terminal.     

The many facets of SDF-1alpha, CXCR4 agonists and antagonists on hematopoietic progenitor cells

Stromal cell-derived factor-1alpha (SDF-1alpha) has pleiotropic effects on hematopoietic progenitor cells (HPCs). We have monitored podia formation, migration, proliferation, and cell-cell adhesion of human HPC under the influence of SDF-1alpha, a peptide agonist of CXCR4 (CTCE-0214), a peptide antagonist (CTCE-9908), and a nonpeptide antagonist (AMD3100). Whereas SDF-1alpha induced migration of CD34(+) cells in a dose-dependent manner, CTCE-0214, CTCE-9908, and AMD3100 did not induce chemotaxis in this concentration range albeit the peptides CTCE-0214 and CTCE-9908 increased podia formation. Cell-cell adhesion of HPC to human mesenchymal stromal cells was impaired by the addition of SDF-1alpha, CTCE-0214, and AMD3100. Proliferation was not affected by SDF-1alpha or its analogs. Surface antigen detection of CXCR4 was reduced upon treatment with SDF-1alpha or AMD3100 and it was enhanced by CTCE-9908. Despite the fact that all these molecules target the same CXCR4 receptor, CXCR4 agonists and antagonists have selective effects on different functions of the natural molecule.     

Role of the SDF-1/CXCR4 axis in the pathogenesis of lung injury and fibrosis

Stromal cell-derived factor-1 (SDF-1) participates in mobilizing bone marrow-derived stem cells, via its receptor CXCR4. We studied the role of the SDF-1/CXCR4 axis in a rodent model of bleomycin-induced lung injury in C57BL/6 wild-type and matrix metalloproteinase (MMP)-9 knockout mice. After intratracheal instillation of bleomycin, SDF-1 levels in serum and bronchial alveolar lavage fluid increased. These changes were accompanied by increased numbers of CXCR4(+) cells in the lung and a decrease in a population of CXCR4(+) cells in the bone marrow that did not occur in MMP-9(-)/(-) mice. Both SDF-1 and lung lysates from bleomycin-treated mice induced migration of bone marrow-derived stem cells in vitro that was blocked by a CXCR4 antagonist, TN14003. Treatment of mice with TN14003 with bleomycin-induced lung injury significantly attenuated lung fibrosis. Lung tissue from patients with idiopathic pulmonary fibrosis had higher numbers of cells expressing both SDF-1 and CXCR4 than did normal lungs. Our data suggest that the SDF-1/CXCR4 axis is important in the complex sequence of events triggered by bleomycin exposure that eventuates in lung repair. SDF-1 participates in mobilizing bone marrow-derived stem cells, via its receptor CXCR4.     

基质细胞衍生因子-1及其受体CXCR4在肿瘤转移中的作用

基质细胞衍生因子-1(Stromal cell-derived factor-1,SDF-1)及其受体CXCR4与人类多种肿瘤转移密切相关,CXCR4在一些肿瘤细胞系、原发肿瘤组织均呈高表达。SDF-1在肿瘤细胞潜在转移靶器官的表达量比非常规转移靶器官高,肿瘤细胞利用CXCR4与其天然配体间的趋化效应实现远距离转移。SDF-1/CXCR4驱动癌细胞转移模式的提出及其相互作用机制的深入研究对于肿瘤治疗具有重要的指导意义。     

趋化因子基质细胞衍生因子1(SDF-1)及其受体CXCR4

趋化因子及其受体在免疫和炎症反应、造血以及HIV感染等方面发挥重要作用,其中基质细胞衍生因子-1SDF-1及其受体CXCR4由于在造血干细胞迁移、归巢以及HIV感染中的作用而受到关注,并对其作用机制进行了探讨,现就SDF-1及其受体CXCR4的有关内容作一综述。     

SDF-1/CXCR4在滋养层细胞中的表达及其在母-胎免疫耐受中的作用

目的:研究趋化因子SDF1及其配体CXCR4在滋养层细胞中的表达及其在母胎免疫耐受中的作用。方法:取早孕期的绒毛,分离纯化培养绒毛外滋层养细胞(extravilloustrophoblast,EVT),用免疫细胞化学染色法检测SDF1与CXCR4在绒毛中的表达。用流式细胞术筛选源于滋养层细胞高表达CXCR4的绒癌细胞株用于体外微孔隔离室迁移实验,以分析SDF1的趋化活性。用免疫组织化学染色法检测早孕期绒毛及足月妊娠胎盘中SDF1及CXCR4的表达。结果:在EVT中可检出SDF1和CXCR4的表达,在一定范围内,SDF1的趋化活性与其浓度呈正相关(r=0.68,P<0.01)。10μg/L的SDF1趋化作用最强,最大趋化指数CI为1.62±0.12。在早孕期的绒毛及足月胎盘中,滋养层细胞的胞膜和细胞质中均检出SDF1和CXCR4的表达,但在足月胎盘中的表达强度明显低于早孕期的绒毛组织(P<0.01)。结论:SDF1/CXCR4在妊娠中发挥着重要作用,对维系母胎免疫耐受具有重要意义。