CXCR4/CXCL12在原发中枢神经系统淋巴瘤中的表达及其意义

目的 探讨趋化因子受体CXCR4 及其配体CXCL12 在原发中枢神经系统淋巴瘤中的表达水平,分析它们在原发中枢神经系统淋巴瘤的发生、发展过程中的可能作用.方法 采用免疫组化EnVision 二步法检测CXCR4 及CXCL12 在5 例原发中枢神经系统淋巴瘤、10 例正常脑组织细胞中的表达.采用半定量RT-PCR 检测CXCR4 和CXCL12 在5 例原发中枢神经系统淋巴瘤以及正常脑组织中的表达情况.结果 免疫组化EnVision二步法:CXCR4 在肿瘤标本中阳性表达率为100% (5/5),在正常脑组织标本中阳性表达率为0% (0/10);CXCL12 在肿瘤标本中阳性表达率为100% (5/5),在正常脑组织标本中阳性表达率为100% (10/10).半定量RT-PCR法检测标本中的CXCR4、CXCL12 显示:在肿瘤标本中全部检出,而在正常脑组织标本中仅检出CXCL12 的表达.结论 CXCR4/CXCL12 信号通路在原发中枢神经系统淋巴瘤的发生、发展过程中起作用.     

人脑胶质瘤CXCL12基因的甲基化分析研究

Objective To detect the methylation status of CXCL12 gene and the mRNA expression of CXCL12, CXCR4 and DNA methyhransferases (DNMTs) in glioma, and to analyze the methylation regulation and mechanism of CXCL12/CXCR4 signaling axis in the malignant progress of glioma. Methods The mRNA expression of CXCL12, CXCR4, DNMT1, DNMT3A and DNMT3B was detected by the semi - quantitative RT - PCR and real - time PCR in 76 gliomas and 10 normal brain tissues. The methylation status of CXCL12 in glioma was also studied by the methylation specific PCR. Results ( 1 ) The mRNA expression of CXCR4 in glioma increased with WHO grades. (2) Methylation of CXCL12 was detected in 34. 2% ( 26/76 ) of gliomas, but the methylation rate decreased with WHO grades. ( 3 ) Epigenetic inactivation of CXCL12 mainly happened in low- grade gliomas, and the CXCL12 mRNA levels were closely related to its methylation status. (4) The expression levels of these three DNMT genes were significantly higher in the CXCL12 - methylated gliomas than in the CXCL12 - unmethylated ones. Conclusion The CXCR4 gene may be a marker of aggressive biological behavior of glioma. The CXCL12 promoter hypermethylation is detected mainly in low - grade gliomas. And the methylaiton of CXCL12 gene cause the down - regulation of its mRNA levels in low - grade gliomas. The high expressions of DNMT1、DNMT3A and DNMT3B may be the potential mechanism of CXCL12 methylation.     

人脑胶质瘤CXCL12基因的甲基化分析研究

Objective To detect the methylation status of CXCL12 gene and the mRNA expression of CXCL12, CXCR4 and DNA methyhransferases (DNMTs) in glioma, and to analyze the methylation regulation and mechanism of CXCL12/CXCR4 signaling axis in the malignant progress of glioma. Methods The mRNA expression of CXCL12, CXCR4, DNMT1, DNMT3A and DNMT3B was detected by the semi - quantitative RT - PCR and real - time PCR in 76 gliomas and 10 normal brain tissues. The methylation status of CXCL12 in glioma was also studied by the methylation specific PCR. Results ( 1 ) The mRNA expression of CXCR4 in glioma increased with WHO grades. (2) Methylation of CXCL12 was detected in 34. 2% ( 26/76 ) of gliomas, but the methylation rate decreased with WHO grades. ( 3 ) Epigenetic inactivation of CXCL12 mainly happened in low- grade gliomas, and the CXCL12 mRNA levels were closely related to its methylation status. (4) The expression levels of these three DNMT genes were significantly higher in the CXCL12 - methylated gliomas than in the CXCL12 - unmethylated ones. Conclusion The CXCR4 gene may be a marker of aggressive biological behavior of glioma. The CXCL12 promoter hypermethylation is detected mainly in low - grade gliomas. And the methylaiton of CXCL12 gene cause the down - regulation of its mRNA levels in low - grade gliomas. The high expressions of DNMT1、DNMT3A and DNMT3B may be the potential mechanism of CXCL12 methylation.     

人脑胶质瘤CXCL12基因的甲基化分析研究

Objective To detect the methylation status of CXCL12 gene and the mRNA expression of CXCL12, CXCR4 and DNA methyhransferases (DNMTs) in glioma, and to analyze the methylation regulation and mechanism of CXCL12/CXCR4 signaling axis in the malignant progress of glioma. Methods The mRNA expression of CXCL12, CXCR4, DNMT1, DNMT3A and DNMT3B was detected by the semi - quantitative RT - PCR and real - time PCR in 76 gliomas and 10 normal brain tissues. The methylation status of CXCL12 in glioma was also studied by the methylation specific PCR. Results ( 1 ) The mRNA expression of CXCR4 in glioma increased with WHO grades. (2) Methylation of CXCL12 was detected in 34. 2% ( 26/76 ) of gliomas, but the methylation rate decreased with WHO grades. ( 3 ) Epigenetic inactivation of CXCL12 mainly happened in low- grade gliomas, and the CXCL12 mRNA levels were closely related to its methylation status. (4) The expression levels of these three DNMT genes were significantly higher in the CXCL12 - methylated gliomas than in the CXCL12 - unmethylated ones. Conclusion The CXCR4 gene may be a marker of aggressive biological behavior of glioma. The CXCL12 promoter hypermethylation is detected mainly in low - grade gliomas. And the methylaiton of CXCL12 gene cause the down - regulation of its mRNA levels in low - grade gliomas. The high expressions of DNMT1、DNMT3A and DNMT3B may be the potential mechanism of CXCL12 methylation.     

人脑胶质瘤CXCL12基因的甲基化分析研究

Objective To detect the methylation status of CXCL12 gene and the mRNA expression of CXCL12, CXCR4 and DNA methyhransferases (DNMTs) in glioma, and to analyze the methylation regulation and mechanism of CXCL12/CXCR4 signaling axis in the malignant progress of glioma. Methods The mRNA expression of CXCL12, CXCR4, DNMT1, DNMT3A and DNMT3B was detected by the semi - quantitative RT - PCR and real - time PCR in 76 gliomas and 10 normal brain tissues. The methylation status of CXCL12 in glioma was also studied by the methylation specific PCR. Results ( 1 ) The mRNA expression of CXCR4 in glioma increased with WHO grades. (2) Methylation of CXCL12 was detected in 34. 2% ( 26/76 ) of gliomas, but the methylation rate decreased with WHO grades. ( 3 ) Epigenetic inactivation of CXCL12 mainly happened in low- grade gliomas, and the CXCL12 mRNA levels were closely related to its methylation status. (4) The expression levels of these three DNMT genes were significantly higher in the CXCL12 - methylated gliomas than in the CXCL12 - unmethylated ones. Conclusion The CXCR4 gene may be a marker of aggressive biological behavior of glioma. The CXCL12 promoter hypermethylation is detected mainly in low - grade gliomas. And the methylaiton of CXCL12 gene cause the down - regulation of its mRNA levels in low - grade gliomas. The high expressions of DNMT1、DNMT3A and DNMT3B may be the potential mechanism of CXCL12 methylation.     

人脑胶质瘤CXCL12基因的甲基化分析研究

Objective To detect the methylation status of CXCL12 gene and the mRNA expression of CXCL12, CXCR4 and DNA methyhransferases (DNMTs) in glioma, and to analyze the methylation regulation and mechanism of CXCL12/CXCR4 signaling axis in the malignant progress of glioma. Methods The mRNA expression of CXCL12, CXCR4, DNMT1, DNMT3A and DNMT3B was detected by the semi - quantitative RT - PCR and real - time PCR in 76 gliomas and 10 normal brain tissues. The methylation status of CXCL12 in glioma was also studied by the methylation specific PCR. Results ( 1 ) The mRNA expression of CXCR4 in glioma increased with WHO grades. (2) Methylation of CXCL12 was detected in 34. 2% ( 26/76 ) of gliomas, but the methylation rate decreased with WHO grades. ( 3 ) Epigenetic inactivation of CXCL12 mainly happened in low- grade gliomas, and the CXCL12 mRNA levels were closely related to its methylation status. (4) The expression levels of these three DNMT genes were significantly higher in the CXCL12 - methylated gliomas than in the CXCL12 - unmethylated ones. Conclusion The CXCR4 gene may be a marker of aggressive biological behavior of glioma. The CXCL12 promoter hypermethylation is detected mainly in low - grade gliomas. And the methylaiton of CXCL12 gene cause the down - regulation of its mRNA levels in low - grade gliomas. The high expressions of DNMT1、DNMT3A and DNMT3B may be the potential mechanism of CXCL12 methylation.     

人脑胶质瘤CXCL12基因的甲基化分析研究

Objective To detect the methylation status of CXCL12 gene and the mRNA expression of CXCL12, CXCR4 and DNA methyhransferases (DNMTs) in glioma, and to analyze the methylation regulation and mechanism of CXCL12/CXCR4 signaling axis in the malignant progress of glioma. Methods The mRNA expression of CXCL12, CXCR4, DNMT1, DNMT3A and DNMT3B was detected by the semi - quantitative RT - PCR and real - time PCR in 76 gliomas and 10 normal brain tissues. The methylation status of CXCL12 in glioma was also studied by the methylation specific PCR. Results ( 1 ) The mRNA expression of CXCR4 in glioma increased with WHO grades. (2) Methylation of CXCL12 was detected in 34. 2% ( 26/76 ) of gliomas, but the methylation rate decreased with WHO grades. ( 3 ) Epigenetic inactivation of CXCL12 mainly happened in low- grade gliomas, and the CXCL12 mRNA levels were closely related to its methylation status. (4) The expression levels of these three DNMT genes were significantly higher in the CXCL12 - methylated gliomas than in the CXCL12 - unmethylated ones. Conclusion The CXCR4 gene may be a marker of aggressive biological behavior of glioma. The CXCL12 promoter hypermethylation is detected mainly in low - grade gliomas. And the methylaiton of CXCL12 gene cause the down - regulation of its mRNA levels in low - grade gliomas. The high expressions of DNMT1、DNMT3A and DNMT3B may be the potential mechanism of CXCL12 methylation.     

人脑胶质瘤CXCL12基因的甲基化分析研究

Objective To detect the methylation status of CXCL12 gene and the mRNA expression of CXCL12, CXCR4 and DNA methyhransferases (DNMTs) in glioma, and to analyze the methylation regulation and mechanism of CXCL12/CXCR4 signaling axis in the malignant progress of glioma. Methods The mRNA expression of CXCL12, CXCR4, DNMT1, DNMT3A and DNMT3B was detected by the semi - quantitative RT - PCR and real - time PCR in 76 gliomas and 10 normal brain tissues. The methylation status of CXCL12 in glioma was also studied by the methylation specific PCR. Results ( 1 ) The mRNA expression of CXCR4 in glioma increased with WHO grades. (2) Methylation of CXCL12 was detected in 34. 2% ( 26/76 ) of gliomas, but the methylation rate decreased with WHO grades. ( 3 ) Epigenetic inactivation of CXCL12 mainly happened in low- grade gliomas, and the CXCL12 mRNA levels were closely related to its methylation status. (4) The expression levels of these three DNMT genes were significantly higher in the CXCL12 - methylated gliomas than in the CXCL12 - unmethylated ones. Conclusion The CXCR4 gene may be a marker of aggressive biological behavior of glioma. The CXCL12 promoter hypermethylation is detected mainly in low - grade gliomas. And the methylaiton of CXCL12 gene cause the down - regulation of its mRNA levels in low - grade gliomas. The high expressions of DNMT1、DNMT3A and DNMT3B may be the potential mechanism of CXCL12 methylation.     

人脑胶质瘤CXCL12基因的甲基化分析研究

Objective To detect the methylation status of CXCL12 gene and the mRNA expression of CXCL12, CXCR4 and DNA methyhransferases (DNMTs) in glioma, and to analyze the methylation regulation and mechanism of CXCL12/CXCR4 signaling axis in the malignant progress of glioma. Methods The mRNA expression of CXCL12, CXCR4, DNMT1, DNMT3A and DNMT3B was detected by the semi - quantitative RT - PCR and real - time PCR in 76 gliomas and 10 normal brain tissues. The methylation status of CXCL12 in glioma was also studied by the methylation specific PCR. Results ( 1 ) The mRNA expression of CXCR4 in glioma increased with WHO grades. (2) Methylation of CXCL12 was detected in 34. 2% ( 26/76 ) of gliomas, but the methylation rate decreased with WHO grades. ( 3 ) Epigenetic inactivation of CXCL12 mainly happened in low- grade gliomas, and the CXCL12 mRNA levels were closely related to its methylation status. (4) The expression levels of these three DNMT genes were significantly higher in the CXCL12 - methylated gliomas than in the CXCL12 - unmethylated ones. Conclusion The CXCR4 gene may be a marker of aggressive biological behavior of glioma. The CXCL12 promoter hypermethylation is detected mainly in low - grade gliomas. And the methylaiton of CXCL12 gene cause the down - regulation of its mRNA levels in low - grade gliomas. The high expressions of DNMT1、DNMT3A and DNMT3B may be the potential mechanism of CXCL12 methylation.     

人脑胶质瘤CXCL12基因的甲基化分析研究

Objective To detect the methylation status of CXCL12 gene and the mRNA expression of CXCL12, CXCR4 and DNA methyhransferases (DNMTs) in glioma, and to analyze the methylation regulation and mechanism of CXCL12/CXCR4 signaling axis in the malignant progress of glioma. Methods The mRNA expression of CXCL12, CXCR4, DNMT1, DNMT3A and DNMT3B was detected by the semi - quantitative RT - PCR and real - time PCR in 76 gliomas and 10 normal brain tissues. The methylation status of CXCL12 in glioma was also studied by the methylation specific PCR. Results ( 1 ) The mRNA expression of CXCR4 in glioma increased with WHO grades. (2) Methylation of CXCL12 was detected in 34. 2% ( 26/76 ) of gliomas, but the methylation rate decreased with WHO grades. ( 3 ) Epigenetic inactivation of CXCL12 mainly happened in low- grade gliomas, and the CXCL12 mRNA levels were closely related to its methylation status. (4) The expression levels of these three DNMT genes were significantly higher in the CXCL12 - methylated gliomas than in the CXCL12 - unmethylated ones. Conclusion The CXCR4 gene may be a marker of aggressive biological behavior of glioma. The CXCL12 promoter hypermethylation is detected mainly in low - grade gliomas. And the methylaiton of CXCL12 gene cause the down - regulation of its mRNA levels in low - grade gliomas. The high expressions of DNMT1、DNMT3A and DNMT3B may be the potential mechanism of CXCL12 methylation.     

人脑胶质瘤CXCL12基因的甲基化分析研究

Objective To detect the methylation status of CXCL12 gene and the mRNA expression of CXCL12, CXCR4 and DNA methyhransferases (DNMTs) in glioma, and to analyze the methylation regulation and mechanism of CXCL12/CXCR4 signaling axis in the malignant progress of glioma. Methods The mRNA expression of CXCL12, CXCR4, DNMT1, DNMT3A and DNMT3B was detected by the semi - quantitative RT - PCR and real - time PCR in 76 gliomas and 10 normal brain tissues. The methylation status of CXCL12 in glioma was also studied by the methylation specific PCR. Results ( 1 ) The mRNA expression of CXCR4 in glioma increased with WHO grades. (2) Methylation of CXCL12 was detected in 34. 2% ( 26/76 ) of gliomas, but the methylation rate decreased with WHO grades. ( 3 ) Epigenetic inactivation of CXCL12 mainly happened in low- grade gliomas, and the CXCL12 mRNA levels were closely related to its methylation status. (4) The expression levels of these three DNMT genes were significantly higher in the CXCL12 - methylated gliomas than in the CXCL12 - unmethylated ones. Conclusion The CXCR4 gene may be a marker of aggressive biological behavior of glioma. The CXCL12 promoter hypermethylation is detected mainly in low - grade gliomas. And the methylaiton of CXCL12 gene cause the down - regulation of its mRNA levels in low - grade gliomas. The high expressions of DNMT1、DNMT3A and DNMT3B may be the potential mechanism of CXCL12 methylation.     

AMD3100、CXCR7抗体对自身免疫性脑脊髓炎大鼠脊髓和脾细胞SDF1α、CXCR4、CXCR7 mRNA表达的影响

目的研究AMD3100、CXCR7抗体对实验性自身免疫性脑脊髓炎(experimental autoimmune en-cephalomyelitis,EAE)大鼠脊髓和脾脏中趋化因子SDF1α及其受体CXCR4、CXCR7表达的影响。方法采用MBP68-86和完全福氏佐剂配置的完全抗原免疫Lewis大鼠制备EAE模型。将大鼠随机分为对照组、AMD3100组、CXCR7抗体组和EAE组,于免疫后第0、2、4、6天给予相应药物干预:AMD3100组按体质量2.5mg/kg腹腔注射AMD3100,CXCR7抗体组腹腔注射CXCR7抗体20μg/只,EAE组腹腔注射等量生理盐水。每天对大鼠进行神经功能评分,免疫后第15天行RT-PCR检测各组脊髓及脾脏中SDF1α、CXCR4、CXCR7mRNA表达,行HE染色观察大鼠脊髓组织病理变化。结果 (1)与对照组相比,EAE组大鼠脊髓血管周围有大量性炎细胞浸润,神经功能评分明显增加,AMD3100组、CXCR7抗体组和EAE组脊髓SDF1α、CXCR4、CXCR7 mRNA表达增加(P<0.01),脾细胞SDF1α、CXCR7 mRNA表达减少(P<0.01);(2)与EAE组相比,AMD3100组大鼠神经功能评分增加,脾细胞CXCR4、CXCR7 mRNA表达增加(P<0.01),脊髓SDF1α、CXCR4、CXCR7表达无统计学差异;(3)与EAE组相比,CXCR7抗体组大鼠神经功能评分增加,脾细胞SDF1α、CXCR4、CXCR7 mRNA表达增加(P<0.01),脊髓SDF1α、CXCR4、CXCR7 mRNA表达无统计学差异。结论 AMD3100和CXCR7抗体均能加重EAE病情,上调EAE脾细胞CXCR4和CXCR7 mRNA的表达。     

CXCL10/CXCR3 Signaling in the DRG Exacerbates Neuropathic Pain in Mice

Chemokines and receptors have been implicated in the pathogenesis of chronic pain.Here,we report that spinal nerve ligation(SNL)increased CXCR3 expression in dorsal root ganglion(DRG)neurons,and intra-DRG injection of Cxcr3 shRNA attenuated the SNL-induced mechanical allodynia and heat hyperalgesia.SNL also increased the m RNA levels of CXCL9,CXCL10,and CXCL11,whereas only CXCL10 increased the number of action potentials(APs)in DRG neurons.Furthermore,in Cxcr3^-/-mice,CXCL10 did not increase the number of APs,and the SNL-induced increase of the numbers of APs in DRG neurons was reduced.Finally,CXCL10 induced the activation of p38 and ERK in ND7-23 neuronal cells and DRG neurons.Pretreatment of DRG neurons with the P38 inhibitor SB203580 decreased the number of APs induced by CXCL10.Our data indicate that CXCR3,activated by CXCL10,mediates p38 and ERK activation in DRG neurons and enhances neuronal excitability,which contributes to the maintenance of neuropathic pain.     

人脑胶质瘤CXCL12基因的甲基化分析研究

目的 检测胶质瘤CXCL12基因启动子区的甲基化状态及其mRNA表达水平,以及受体CXCR4、DNA甲基转移酶等基因的mRNA表达情况,分析甲基化在CXCL12/CXCR4生物轴参与胶质瘤恶性进展中的调控机制.方法 半定量RT-PCR和实时定量PCR检测CXCL12、CXCR4、DNMT1、DNMT3A和DNMT3B基闪在76例胶质瘤及10例正常脑组织中的表达情况;甲基化PCR检测CXCL12基因启动子区的甲基化状态.结果 (1)CXCR4 mRNA随胶质瘤恶性程度的增高而表达增加;(2)CXCL12基因在胶质瘤中的甲基化率为34.2%,甲基化率随胶质瘤恶性程度的增高而降低;(3)CXCL12基因的甲基化主要发生在低度恶性胶质瘤中,其甲基化状态与mRNA表达密切相关;(4)DNMT1、DNMT3A和DNMT3B在CXCL12基因甲基化胶质瘤中的表达明显高于未发生甲基化的胶质瘤.结论 CXCR4基因有望成为胶质瘤恶性程度的生物学标志;CXCL12基因启动子区的甲基化主要发生在低度恶性胶质瘤中,其CXCL12基因甲基化下调mRNA的表达;DNMT1、DNMT3A和DNMT3B的过表达可能参与CXCL12基因甲基化的调控.     

白细胞介素2、6、10在猴实验性变态反应性脑脊髓炎发病中的作用

目的 了解血和脑脊液白细胞介素(IL)-2、IL-6、IL-10在猴实验性变态反应性脑脊髓炎(EAE)发病机制和病情转归中的作用,并进一步阐明多发性硬化(MS)发病的免疫学机制.方法 用猴脑制成脑白质匀浆乳化剂,先制作猴EAE模型10只;随机选另1只猴,用完全福氏佐剂(CFA)0.4 ml皮下注射作对照组.然后对 EAE进行临床病情分级和病程分期,并在不同时期收集血和脑脊液的上清液,用酶增敏免疫分析法测定IL-2、IL-6、IL-10的浓度,用配对t检验进行统计学处理.结果 猴EAE发病前后血中IL-2、IL-6、IL-10有轻度变化,IL-2、IL-6发病后较发病前升高,但差异无显著意义.而猴EAE急性期第1、3周脑脊液IL-2(分别为5.0±0.8和5.3±1.2)较发病前(0.7±0.3)明显升高,P值分别为0.045,0.041,恢复期或慢性期IL-6、IL-10明显升高,P值各为0.004 3,0.006 5,差异有显著意义.结论 IL-2正向调节免疫,使EAE猴的病情加重;IL-6、IL-10负向调节免疫,使EAE猴的病情减轻.此结果 对今后研究EAE或MS的免疫学机制可能有重要指导作用.     

CXCR4在胶质瘤细胞中的表达及对迁移的影响

目的检测趋化因子受体CXCR4在胶质瘤细胞的表达。建立侵袭迁移模型,分析CXCR4在CXCL12作用下对U251细胞迁移的影响机制。方法间接免疫荧光法检测CXCR4在U251的表达。流式细胞术(flow cytometry,FCM)检测不同病理级别胶质瘤CXCR4的表达。建立琼脂糖下细胞迁移(Under-agarose cell migration assay)模型,研究U251在不同浓度CXCL12下的侵袭能力。设空白组与实验组,实验组以CXCL12浓度分5组。计算趋化系数(chemotaxis coefficient,cc)。结果 (1) CXCR4表达于U251细胞。(2)Ⅰ、Ⅱ、Ⅲ、Ⅳ级别胶质瘤CXCR4表达率分别为21. 36±2. 70%、26. 39±4. 27%、52. 59±2. 37%、56. 23±1. 24%。四个级别胶质瘤CXCR4的阳性率均有显著差异(P 0. 05)。(3)对照组细胞迁移距离为40. 85±5. 16μm,实验组细胞迁移距离分别为49±2. 26μm、105. 6±3. 82μm、165. 3±3. 89μm、245. 4±5. 94μm、161. 45±3. 18μm。因子浓度为200～500 ng/ml时与阴性组相比细胞发生明显迁移(P 0. 05)。结论 (1)胶质瘤细胞U251表达CXCR4。(2)胶质瘤的病理级别越高CXCR4的阳性率越大。(3)成功建立了胶质瘤细胞琼脂糖下侵袭模型,为研究肿瘤细胞迁移提供新的方法; CXCL12对胶质瘤有明显的趋化作用,肿瘤细胞顺因子浓度梯度定向迁移。     

趋化因子CXCL12及其受体CXCR4与造釉型颅咽管瘤侵袭、复发的相关性研究

目的探讨趋化因子及其受体(CXCL12/CXCR4)在造釉细胞型颅咽管瘤中的表达并分析其与肿瘤侵袭、复发的相关性。方法应用免疫组化法和western blot方法对20例造釉细胞型颅咽管瘤标本(原发组11例,复发组9例)中CXCL12/CXCR4的表达进行检测。结果 CXCL12/CXCR4在复发组造釉细胞型颅咽管瘤中的阳性表达明显高于原发组(P<0.05)。结论 CXCL12/CXCR4可能在造釉细胞型颅咽管瘤侵袭、复发过程中起重要的作用。CXCL12/CXCR4可能成为评价造釉细胞型颅咽管瘤侵袭性生长和复发的标记物。     

Upregulation of Chemokine CXCL12 in the Dorsal Root Ganglia and Spinal Cord Contributes to the Development and Maintenance of Neuropathic Pain Following Spared Nerve Injury in Rats

Emerging evidence indicates that CXCL12/CXCR4 signaling is involved in chronic pain. However, few studies have systemically assessed its role in direct nerve injury-induced neuropathic pain and the underlying mechanism. Here, we determined that spared nerve injury(SNI)increased the expression of CXCL12 and its cognate receptor CXCR4 in lumbar 5 dorsal root ganglia(DRG)neurons and satellite glial cells. SNI also induced longlasting upregulation of CXCL12 and CXCR4 in the ipsilateral L4–5 spinal cord dorsal horn, characterized by CXCL12 expression in neurons and microglia, and CXCR4 expression in neurons and astrocytes. Moreover, SNIinduced a sustained increase in TNF-a expression in the DRG and spinal cord. Intraperitoneal injection(i.p.) of the TNF-a synthesis inhibitor thalidomide reduced the SNI-induced mechanical hypersensitivity and inhibited the expression of CXCL12 in the DRG and spinal cord.Intrathecal injection(i.t.) of the CXCR4 antagonist AMD3100, both 30 min before and 7 days after SNI,reduced the behavioral signs of allodynia. Rats given an i.t.or i.p. bolus of AMD3100 on day 8 of SNI exhibited attenuated abnormal pain behaviors. The neuropathic pain established following SNI was also impaired by i.t. administration of a CXCL12-neutralizing antibody. Moreover,repetitive i.t. AMD3100 administration prevented the activation of ERK in the spinal cord. The mechanical hypersensitivity induced in na?¨ve rats by i.t. CXCL12 was alleviated by pretreatment with the MEK inhibitor PD98059. Collectively, our results revealed that TNF-a might mediate the upregulation of CXCL12 in the DRG and spinal cord following SNI, and that CXCL12/CXCR4 signaling via ERK activation contributes to the development and maintenance of neuropathic pain.     

CXCR4 signaling in central nervous system regeneration: friend or foe?

The knockout of the chemokine C-X-C motif chemokine receptor 4(CXCR4)in growthstimulated retinal ganglion cells(RGCs)has a multiplicative effect on optic nerve regeneration.C-X-C motif chemokine ligand 12(CXCL12),the exclusive ligand of CXCR4.     

Increased CXCL13 and CXCR5 in Anterior Cingulate Cortex Contributes to Neuropathic Pain-Related Conditioned Place Aversion

Pain consists of sensory-discriminative and emotional-affective components.The anterior cingulate cortex(ACC)is a critical brain area in mediating the affective pain.However,the molecular mechanisms involved remain largely unknown.Our recent study indicated that C-X-C motif chemokine 13(CXCL13)and its sole receptor CXCR5 are involved in sensory sensitization in the spinal cord after spinal nerve ligation(SNL).Whether CXCL13/CXCR5 signaling in the ACC contributes to the pathogenesis of pain-related aversion remains unknown.Here,we showed that SNL increased the CXCL13 level and CXCR5 expression in the ACC after SNL.Knockdown of CXCR5 by microinjection of Cxcr5 shRNA into the ACC did not affect SNL-induced mechanical allodynia but effectively alleviated neuropathic painrelated place avoidance behavior.Furthermore,electrophysiological recording from layer Ⅱ-Ⅲ neurons in the ACC showed that SNL increased the frequency and amplitude of spontaneous excitatory postsynaptic currents(sEPSCs),decreased the EPSC paired-pulse ratio,and increased the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor/N-methyl-D-aspartate receptor ratio,indicating enhanced glutamatergic synaptic transmission.Finally,superfusion of CXCL13 onto ACC slices increased the frequency and amplitude of spontaneous EPSCs.Pre-injection of Cxcr5 shRNA into the ACC reduced the increase in glutamatergic synaptic transmis sion induced by SNL.Collectively,these results suggest that CXCL13/CXCR5 signaling in the ACC is involved in neuropathic pain-related aversion via synaptic potentiation.