急性脊髓损伤后差异蛋白的表达

背景：在质谱分析中,任何一种同位素标记相对和绝对定量试剂标记的不同样本中的同一蛋白质表现为相同的质荷比,而在串联质谱中,信号离子表现为不同质荷比(114-121)的峰,因此可以分析得到相关蛋白质的定量信息。 目的：建立大鼠急性脊髓损伤后脊髓组织差异蛋白质谱,应用同位素标记相对和绝对定量技术联合LC-MS/MS质谱技术从分子水平来探索脊髓差异蛋白的表达情况。 方法：取8只SD大鼠,参照Allen’s等方法建立大鼠急性脊髓损伤模型,随机分为脊髓损伤后0 h组和8 h组,每组各4只。损伤后取脊髓组织,用同位素标记相对和绝对定量技术分析大鼠急性脊髓损伤后脊髓组织的差异蛋白质。 结果与结论：共鉴定到了220个差异表达的蛋白,上调的差异蛋白数是116个,下调的差异蛋白有104个。其中相关神经再生的差异蛋白12个,其中上调的有7个,下调的有5个。提示实验中检测到的多种差异蛋白及表达明显的神经生长因子可能作为急性脊髓损伤的生物标记物或可能作为临床管理监测急性脊髓损伤的损伤进程、靶向治疗及评估疗效的有力证据。     

大鼠急性脊髓损伤后NeuroD的时空表达

目的:探讨神经源性分化因子NeuroD在大鼠急性脊髓损伤过程中的表达及意义。方法:以改良Allen's法建立急性脊髓损伤(SCI)大鼠模型,以假手术组为对照,应用免疫组织化学、半定量RT-PCR、免疫印迹分别检测脊髓损伤后不同时间点NeuroD的表达变化。结果:NeuroD特异性表达于脊髓灰质,与对照组相比,急性脊髓损伤后3 d,NeuroD mRNA的相对表达量明显增加,5 d达到峰值,7 d后回落;Neurod的蛋白相对表达量则在急性脊髓损伤5 d后明显升高,持续至第7天,14 d明显回落。结论:急性脊髓损伤可上调NeuroD表达水平,提示NeuroD参与了急性脊髓损伤后的病理过程。     

c-fos expression in bladder-specific spinal neurons after spinal cord injury using pseudorabies virus

PURPOSE: c-fos expression in spinal neurons that are activated by lower urinary tract stimulation are not organ specific. In this experiment, we demonstrated changes of c-fos expression in bladder-specific preganglionic neurons (PGNs) and interneurons using pseudorabies virus (PRV). MATERIALS AND METHODS: Forty Sprague-Dawley rats were used. We identified the neuronal pathway associated with the bladder by injecting PRV into the detrusor. An immunohistochemical method was used to stain Fos-protein encoded by the c-fos gene. Immunofluorescent staining for PRV was performed to evaluate changes in bladder-specific spinal neurons. RESULTS: Immunofluorescent staining with choline acetyltransferase (ChAT) revealed that the sacral parasympathetic nucleus (SPN) regions contained 9.8 PGNs/section. In rats with chronic spinal cord injury by intravesical saline instillation, 82.4+/-10.3% of PGNs in SPN exhibited Fos-immunoreactive (IR). Two and a half days after PRV infection, PRV-IR PGNs were observed at 5.4 PGNs/section, and 2.7+/-1.6% of them exhibited Fos-IR. Unlike ChAT-IR PGNs, PRV-IR PGNs are bladder-specific neurons and PRV-IR and Fos-IR cells found in the back of PRV-IR PGNs are bladder-specific interneurons. Three days after PRV infection, we observed many PRV-IR and Fos-IR cells in the dorsal commissure. These neurons are interneurons distributed in the bladder. CONCLUSION: We confirmed that in chronic spinal cord injury, the patterns of c-fos expression in bladder-specific spinal neurons were similar to those in voiding-reflex related spinal neurons, which had already been demonstrated earlier. We believe that our methodology can be applied to study interactions between voiding and other organs as well, such as the urethra and prostate.     

脊髓压迫性损伤大鼠海马和脊髓内BDNF的表达变化

目的探讨脑源性神经营养因子(BDNF)在脊髓压迫性损伤后的表达变化及作用。方法用自行设计的方法制作脊髓压迫模型,免疫荧光检测BDNF在星形胶质细胞、神经元和上下行轴突的表达;WB检测BDNF在大鼠海马及脊髓的表达。结果随着时间延长,受损部位的BDNF+-GFAP荧光强度逐渐增强;BDNF+-Tuj1荧光强度逐渐减弱;受损部位相邻上下段的BDNF+-NF200比受损部位的明显增强。海马和脊髓受损中心相邻的上、下段的BDNF蛋白表达在损伤后1d达到峰值,然后逐渐下降(P0.05);而脊髓受损中心的BDNF蛋白表达逐渐下降(P0.05)。结论脊髓损伤后,BDNF的表达下调,随伤后时间呈一定规律变化,是引起受损部位神经元表达下降的原因之一。     

Acute and chronic changes in aquaporin 4 expression after spinal cord injury

The effect of spinal cord injury (SCI) on the expression levels and distribution of water channel aquaporin 4 (AQP4) has not been studied. We have found AQP4 in gray and white matter astrocytes in both uninjured and injured rat spinal cords. AQP4 was detected in astrocytic processes that were tightly surrounding neurons and blood vessels, but more robustly in glia limitans externa and interna, which were forming an interface between spinal cord parenchyma and cerebrospinal fluid (CSF). Such spatial distribution of AQP4 suggests a critical role that astrocytes expressing AQP4 play in the transport of water from blood/CSF to spinal cord parenchyma and vice versa. SCI induced biphasic changes in astrocytic AQP4 levels, including its early down-regulation and subsequent persistent up-regulation. However, changes in AQP4 expression did not correlate well with the onset and magnitude of astrocytic activation, when measured as changes in GFAP expression levels. It appears that reactive astrocytes began expressing increased levels of AQP4 after migrating to the wound area (thoracic region) two weeks after SCI, and AQP4 remained significantly elevated for months after SCI. We also showed that increased levels of AQP4 spread away from the lesion site to cervical and lumbar segments, but only in chronically injured spinal cords. Although overall AQP4 expression levels increased in chronically-injured spinal cords, AQP4 immunolabeling in astrocytic processes forming glia limitans externa was decreased, which may indicate impaired water transport through glia limitans externa. Finally, we also showed that SCI-induced changes in AQP4 protein levels correlate, both temporally and spatially, with persistent increases in water content in acutely and chronically injured spinal cords. Although correlative, this finding suggests a possible link between AQP4 and impaired water transport/edema/syringomyelia in contused spinal cords.     

减压对大鼠脊髓压迫性损伤后脱髓鞘病变和BDNF表达的影响

目的观察脑源性神经生长因子(BDNF)对脊髓压迫性损伤(CSCI)后有髓神经纤维脱髓鞘病变的影响,为阐明BDNF对神经纤维脱髓鞘病变修复提供实验基础。方法将大鼠均分成4组:正常组、假手术组、压迫组和减压组。用自行设计的压迫器制作大鼠脊髓压迫模型。压迫组作脊髓压迫12 h,减压组作脊髓压迫1 h,假手术组仅作脊髓显露,不作压迫。用锇酸染色观察CSCI后1、3和7 d有髓神经纤维变化情况;Western blot和免疫荧光双标检测BDNF和髓鞘碱性蛋白(MBP)的表达。结果压迫组和减压组都出现脱髓鞘病变,并随着时间的延长,髓鞘逐渐水肿、变性、MBP崩解。BDNF表达量在CSCI后随时间延长也逐渐降低(P0.05),但与压迫组相比较,减压组脱髓鞘病变较轻且MBP和BDNF降低幅度小而缓慢(P0.05)。结论 CSCI后尽早减压可减轻脱髓鞘的发生,且可能与BDNF的表达有关。     

Restoring walking after spinal cord injury

One of the most obvious deficits following a spinal cord injury is the difficulty in walking, forcing many patients to use wheelchairs for locomotion. Over the past decade considerable effort has been directed at promoting the recovery of walking and to find effective treatments for spinal cord injury. Advances in our knowledge of the neuronal control of walking have led to the development of a promising rehabilitative strategy in patients with partial spinal cord injury, namely treadmill training with partial weight support. The current focus is on developing more efficient training protocols and automating the training to reduce the physical demand for the therapists. Mechanisms underlying training-induced improvements in walking have been revealed to some extent in animal studies. Another strategy for improving the walking in spinal cord injured patients is the use of functional electric stimulation of nerves and muscles to assist stepping movements. This field has advanced significantly over the past decade as a result of developments in computer technology and the miniaturization of electronics. Finally, basic research on animals with damaged spinal cords has focused on enhancing walking and other motor functions by promoting growth and regeneration of damaged axons. Numerous important findings have been reported yielding optimism that techniques for repairing the injured spinal cord will be developed in the near future. However, at present no strategy involving direct treatment of the injured spinal cord has been established for routine use in spinal cord injured patients. It now seems likely that any successful protocol in humans will require a combination of a treatment to promote re-establishing functional connections to neuronal networks in the spinal cord and specialized rehabilitation training to shape the motor patterns generated by these networks for specific behavioral tasks.     

Local gene delivery from ECM-coated poly(lactide-co-glycolide) multiple channel bridges after spinal cord injury

Tissue engineering scaffolds with complex geometries can provide an architecture that directs tissue formation. Drug delivery from these scaffolds to promote regeneration is often challenging due to the complex fabrication processes. Surface-mediated DNA delivery from multiple channel bridges was applied to deliver lipoplexes in vivo to the injured spinal cord. The surface properties of the polymer, DNA deposition with or without drying, and the presence of ECM components were investigated. In vitro studies revealed that fibronectin produced greater expression levels and immobilization efficiencies compared with collagen, laminin, and no coating. In addition, lipoplex incubation on ECM-coated PLG increased expression relative to either of the drying methods. Additionally, the incubation method had more homogeneously distributed lipoplexes and a higher number of transfected cells relative to the dried conditions. Translation to three-dimensional bridges led to high levels of transgene expression in vitro. In vivo, lipoplexes immobilized to the bridge produced transgene expression levels in a rat spinal cord hemisection model that were 2-fold greater than naked plasmid. Additionally, expression with lipoplexes persisted for at least three weeks. Surface-mediated delivery can be applied to scaffolds with complex geometries to promote transgene expression in vivo.     

脊髓损伤后硫酸软骨素蛋白多糖及GFAP表达的变化

目的探讨脊髓损伤后NG2、Neurocan、GFAP表达的变化。方法将32只雌性SD大鼠随机分为空白对照组和模型组。模型组采用脊髓横切法制作脊髓损伤模型,空白对照组仅切除T10全椎板及T9、T11部分椎板,对脊髓未作任何处理。分别在大鼠脊髓损伤制作后3、7、14及28 d时取材,利用免疫组织化学染色方法检测NG2、Neurocan、GFAP的表达情况。结果模型组脊髓损伤后3 d时NG2的表达出现明显升高,7 d时NG2的表达达到最高点,14 d及28 d时NG2仍然维持在较高水平,但与7 d时的表达相比有下降,空白对照组NG2各时间点均呈低表达。模型组脊髓损伤后7 d时Neurocan的表达显著增加,于14 d时达到最高点,从14 d开始Neurocan的表达开始逐步下降,空白对照组Neurocan各时间点均呈低表达。模型组脊髓损伤后3 d时GFAP的表达明显升高,14 d时GFAP的表达达到顶点,28 d时损伤部位GFAP的表达均较空白对照组明显升高,两组比较差异有统计学意义(均P<0.05)。结论脊髓损伤后NG2、Neurocan、GFAP表达升高,可能是脊髓损伤后抑制轴突再生的因素之一。     

Neurotrophic factors, cellular bridges and gene therapy for spinal cord injury

Injury to the adult mammalian spinal cord results in extensive axonal degeneration, variable amounts of neuronal loss, and often severe functional deficits. Restoration of controlled function depends on regeneration of these axons through an injury site and the formation of functional synaptic connections. One strategy that has emerged for promoting axonal regeneration after spinal cord injury is the implantation of autologous Schwann cells into sites of spinal cord injury to support and guide axonal growth. Further, more recent experiments have shown that neurotrophic factors can also promote axonal growth, and, when combined with Schwann cell grafts, can further amplify axonal extension after injury. Continued preclinical development of these approaches to neural repair may ultimately generate strategies that could be tested in human injury.     

电针上调脊髓损伤后大鼠c-fos mRNA及其蛋白的表达

目的:探讨电针对大鼠脊髓损伤后c-fos mRNA及蛋白表达的影响.方法:将SD雄性大鼠随机分为假手术组、模型组和电针组,采用改良Allen氏重物坠落法制成脊髓损伤模型.分别在1、2、3、5和7d处死动物,使用实时荧光定量PCR技术检测c-fos mRNA表达;使用免疫组织化学显色结合图像定量分析方法检测c-fos蛋白表达.结果:实时荧光定量PCR结果显示,模型组c-fos mRNA表达呈现升高趋势,电针能够促进这种趋势,在术后1d和3d与模型组比较,差异具有统计学意义.免疫组织化学结合图像分析结果显示,模型组c-fos蛋白表达升高趋势较为明显,电针促进这种趋势,且在术后2d与模型组比较,差异具有统计学意义.结论:电针能够促进脊髓损伤后大鼠脊髓损伤部cfos mRNA及蛋白的表达.     

A型肉毒杆菌神经毒素重链干预大鼠脊髓损伤后蛋白表达的初步研究

目的:初步观察大鼠脊髓损伤模型基础上局部注射小剂量A型肉毒杆菌神经毒素重链(BoNT/A HC)后对局部蛋白表达谱的影响,为探讨BoNT/A HC干预在体神经损伤后相关蛋白表达及其干预神经再生机制提供实验基础。方法:复制大鼠单侧腰段脊髓损伤模型;采用SDS-PAGE及双向电泳观察不同剂量BoNT/A HC(2μg、4μg、6μg和8μg)对脊髓损伤后局部(包括损伤部位及其近头端部分脊髓组织)蛋白表达谱的干预作用。结果:大鼠单侧腰段脊髓损伤2 d时局部脊髓组织结构明显破坏崩解,损伤波及左侧脊髓灰质及白质;脊髓损伤局部SDS-PAGE及考马斯亮蓝染色显示,于损伤同时局部一次性注射不同剂量BoNT/A HC后,某些蛋白表达与单纯损伤组相比明显不同,而与正常组基本一致;双向电泳结果进一步显示,损伤局部注射6μg BoNT/A HC后2 d和20 d时,在不同等电点及不同蛋白分子量水平上,有10余种蛋白表达与单纯损伤组明显不同,呈向正常转化的趋势。结论:大鼠脊髓损伤局部注射BoNT/A HC一定时间可影响损伤局部蛋白表达谱的变化,这种变化呈现由损伤造成的蛋白表达变化被转向正常的趋势。     

壳聚糖材料在脊髓损伤后神经再生的研究与作用

背景：组织工程支架材料壳聚糖能复合多种种子细胞和神经因子,维持受损组织正常的解剖结构,防止胶质瘢痕挤压,对脊髓损伤后神经再生具有重要的意义。 目的：介绍壳聚糖材料在修复脊髓损伤后神经再生领域的研究现状。 方法：由第一作者检索1990至2012年 PubMed数据库、CNKI数据库及万方数据库有关壳聚糖材料特性、壳聚糖导管移植治疗脊髓损伤的相关文献。 结果与结论：壳聚糖具有良好的物理、化学性能,并且具有良好的生物相容性、生物降解性,免疫抗原性小和无毒性等特殊生物医学特性,与嗅鞘细胞、骨髓间充质干细胞及神经干细胞具有良好的亲和性。壳聚糖材料制备的神经导管、支架能在脊髓损伤后桥接神经断端,维持神经再生的正常解剖结构,提供种子细胞及细胞因子载体,为损伤后神经再生提供良好的微环境,但目前对于壳聚糖导管的研究仍不够全面,仍有很多问题待解决。     

急性不完全脊髓损伤模型大鼠相关炎症因子的表达

背景：随着现代交通和工矿事业的发展,脊髓损伤成为临床常见的多发病,严重的影响了人类身心健康和生活质量。 目的：检测在大鼠急性脊髓损伤模型中磷酸化信号转导与转录激活因子3（p-STAT3）介导的IL-1β、IL-6、IL-17等炎症因子的表达变化情况,探讨IL-1β、IL-6、IL-17等炎症因子在急性脊髓损伤后炎症反应过程中的作用。 方法：雄性成年SD大鼠75只,随机分为对照组和脊髓损伤1h、6h、24h和72h四个亚组（n=15只）。采用改良Allen氏法建立脊髓损伤模型,对照组仅行椎板全切除术。在建模之后相应的时间点获取损伤段脊髓、脾脏组织,免疫组织化学染色法检测IL-6和IL-17在损伤段脊髓组织中的分布及表达情况,蛋白免疫印迹法检测p-STAT3在损伤段脊髓组织中的表达变化,采用RT-PCR法检测IL-1βmRNA、IL-6mRNA和IL-17AmRNA在脾脏组织中的表达情况。 结果与结论：脊髓损伤后p-STAT3、IL-1β、IL-6和IL-17的表达明显高于对照组（P＜0.05）。损伤后炎症因子表达量立即升高,IL-1β和IL-6在损伤后6h小时到达高峰,随后开始下降;p-STAT3和IL-17在损伤后24h到达高峰,随后开始下降,至损伤后72h表达量仍高于对照组。损伤早期p-STAT3介导的促炎因子IL-1β和IL-6表达增加,可能导致损伤区域炎症级联放大,诱导继发性脊髓损伤;促炎因子IL-17的异常升高,可能在继发性损伤炎症反应中起着重要作用。 中国组织工程研究杂志出版内容重点：肾移植;肝移植;移植;心脏移植;组织移植;皮肤移植;皮瓣移植;血管移植;器官移植;组织工程全文链接：     

大鼠脊髓发育及损伤后NIDD mRNA表达的实验研究

目的：探讨在大鼠发育过程中及急性脊髓损伤后脊髓组织中NIDD （nNOS-interacting DHHC domain-containing protein with dendritic mRNA）mRNA的表达变化及意义。方法：采用改良Allen＇s打击法，咬除T8-10椎板后，造成大鼠脊髓损伤模型，致伤量为10×10g·cm；借助实时荧光定量PCR、原位杂交与免疫荧光结合的方法，定量、定位研究发育过程中及脊髓损伤后早期大鼠脊髓组织中NIDD mRNA与nNOS mRNA表达的时间和空间分布特征。结果：大鼠发育过程中，胚胎16d的大鼠脊髓中可见NIDD mRNA的高表达，在生后1d，与nNOS共表达于尚未分化成熟的前角，在白质也见NIDD的阳性信号。成年后呈低表达；nNOS mRNA于生后1～3d出现表达高峰；脊髓损伤后NIDD mRNA表达明显增多，在8h到达高峰，分布于脊髓前角、中间带、中央管周围及后角nNOS阳性的神经元，7d恢复至正常水平；nNOS mRNA在损伤后8h达到高峰，1d降低至正常水平。而且，在脊髓损伤后NIDD mRNA与nNOS mRNA二者表达呈正相关。结论：胎鼠脊髓中，NIDD高表达于nNOS阳性细胞，提示其在脊髓组织的发育成熟过程中的作用可能与nNOS相关。脊髓损伤后脊髓组织中NIDD与nNOS表达增多，提示在脊髓损伤的病理过程中，NIDD可能通过调节nNOS的细胞亚定位及活性而发挥一定的生物学作用。     

脊髓损伤后的康复实践结果

背景：脊髓损伤患者的康复结果与患者的损伤程度、治疗方法、康复时间及后期治疗等多因素有关。跨学科、全面、专业的脊髓损伤康复单元能为脊髓损伤患者提供更好的恢复。目的：综合评价脊髓损伤康复单元干预或其组合干预的效果。方法：检索2003至2014年Springer及PubMed数据库,检索词：spinal cord injury,rehabilitation practice,outcomes。根据纳入排除标准,阅读标题和摘要进行初筛,选用44篇英文文献进行分析。结果与结论：许多研究采用基于实践证据的方法,识别多种康复实践方法,把信息与结果联系以评价康复干预的效果。研究显示创伤及非创伤性混合样本中的目标实现与年龄没有差异,大多数康复结果很少有性别差异。最初入院到专科脊髓损伤中心的绝大多数脊髓损伤患者的并发症通常最低,患者尽早入住到跨学科、全面、专业的脊髓损伤单位比延迟入住缩短住院总时间。脊髓损伤患者接受正规、全面的门诊医护随访,在健康感知、独立性、抑郁症没有显著差异,但特定继发情况出现频率显著减少、程度减低。 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程     

大鼠脊髓半横断损伤后脊髓神经细胞凋亡与caspase-3的表达

为研究损伤脊髓神经细胞凋亡和相联系的caspase-3的表达,用原位末端标记法(TUNEL)检测了成年大鼠胸脊髓(T9)半横断损伤(hSCI)后脊髓神经细胞的凋亡变化,并用免疫组织化学染色方法观察了caspase-3的表达。结果显示:hSCI后6h损伤侧脊髓腹角即出现较多的TUNEL阳性神经细胞,并持续至5周。损伤脊髓的吻侧段于手术后4d达高峰,尾侧段脊髓于伤后1d达高峰。与假手术组相比,在所有观察的时间点TUNEL阳性神经细胞的数量在损伤侧均有明显增加。caspase-3免疫组化染色显示,与假手术组相比,伤后6h损伤侧脊髓腹角caspase-3表达也明显增加,并持续至5周。以上结果提示hSCI后,脊髓可出现神经细胞凋亡,且此凋亡的发生可能与caspase-3的表达有关。     

Altered beta-1,4-galactosyltransferase I expression during early inflammation after spinal cord contusion injury

Post-traumatic inflammation has been implicated in secondary tissue damage after spinal cord injury (SCI). β-1,4-Galactosyltransferase I (β-1,4-GalT-I) is a key inflammatory mediator that plays a critical role in the initiation and maintenance of inflammatory reaction in diseases. The aim of the current study was to investigate whether β-1,4-GalT-I is expressed in SCI. Spinal cord contusion model was established in adult rats. Real-time PCR and Western blot analysis were used to detect the spatio-temporal expression of β-1,4-GalT-I after SCI. Lectin-fluorescent staining with RCA-I was used to detect the galactosylation of the membrane glycoproteins. The interaction and colocalization between β-1,4-GalT-I and E-selectin in the injured spinal cords were also assessed by immunoprecipitation of E-selectin and double immunofluorescent staining, respectively. Real-time PCR revealed that β-1,4-GalT-I mRNA reached the peak at 1 d after spinal cord contusion. In situ hybridization indicated that β-1,4-GalT-I mRNA was mainly distributed in the local inflammatory cells, adjacent to the center of injury. Double immunofluorescent staining showed that β-1,4-GalT-I mostly overlapped with ED1-positive macrophages 1 d after SCI, partly colocalized with microglia, neutrophils and a few with oligodendrocytes and astrocytes. The result of Lectin-fluorescent staining with RCA-I was similar to that of double immunofluorescent staining. Terminal galactosylation of E-selectin underwent obvious changes between sham and 3 d after SCI by immunoprecipitation of E-selectin. Thus, the transient expression of high levels of β-1,4-GalT-I may provide new insight into the early inflammation after SCI.