Effects of Reg‐2 on Survival of Spinal Cord Neurons In Vitro

Regeneration gene protein 2 (Reg‐2) is a small secreted protein expressed in motor and sensory neurons of spinal cord during developmental stages and following injury of peripheral nerves. Reg‐2 appears to act as a neurotrophic factor and protects injured neurons from death during regeneration. To illustrate these potential protective effects in vitro, we investigated the blocking effects of Reg‐2 antibodies on the survival of primary cultured spinal cord neurons and astrocytes, as well as on neurite outgrowth. In addition, the effects of Reg‐2 in neuron injury models induced by peroxide and mitochondrial poisoning were assessed. Our results showed that Reg‐2 antibody markedly reduced survival and neurite outgrowth from neurons, whereas astrocyte survival was unaffected. Addition of Reg‐2 into the culture medium had no effect on neuron survival or neurite outgrowth. However, the addition of the Reg‐2 into culture media after peroxide treatment or cellular hypoxia insult induced by mitochondrial poisoning can reduce lactate dehydrogenase release levels and cell death. Thus, the data suggests that Reg‐2 is essential for the survival and neurite outgrowth of developing spinal cord neurons but not the survival of glial cells, and that Reg‐2 plays protective effects on spinal cord neurons against injury in vitro. Anat Rec, 2010. © 2010 Wiley‐Liss, Inc.     

功能性电刺激对脊髓损伤的修复作用

目的：回顾功能性电刺激（functional electrical stimulation, FES）对诱导瘫痪或麻痹的肌肉产生功能性或治疗性运动的作用．总结功能性电刺激修复脊髓损伤中应用进展。方法：应用计算机检索CNKI1990年11月至2009年11月有关组织工程修复脊髓损伤方面的文章,检索词”脊髓损伤,电刺激”,限定文献语言种类为中文。同时计算机检索Medline1999年11月至2009年11月有关功能性电刺激在修复脊髓损伤方面的文章,检索词”spinalcordinjury,electricalstimulation”,限定文献语言种类为English。对资料进行初审。选取功能性电刺激修复脊髓损伤方面的相关文献,查找全文,对文献分析,总结研究内容。结果：功能性电刺激通过一定频率电刺激诱导瘫痪或麻痹的肌肉产生功能性或治疗性运动,可以达到改善或恢复被刺激肌肉或肌群功能的目的。功能性电刺激技术可以恢复截瘫患者的部分运动功能。结论：功能性电刺激是现代康复工程领域具有应用前景的一项新的治疗性技术。功能性电刺激技术可以可以达到改善脊髓损伤患者被刺激肌肉或肌群功能,恢复截瘫患者的部分运动功能。     

大鼠脊髓损伤及继发损伤时脊髓诱发电位与运动诱发电位的变化

本文采用改良Ａｌｌｅｎ’ｓ法，分别以５０ｇ／ｃｍ和１００ｇ／ｃｍ打击大鼠Ｔ１３～Ｌ１脊髓，造成不同程度的脊髓损伤，分别观察伤后２４小时内的ＳｐＥＰ和ＣＭＥＰ的变化，以了解不同程度损伤对ＳｐＥＰ和ＣＭＥＰ的影响及ＳｐＥＰ、ＣＭＥＰ的变化与脊髓继发性损伤发展过程的关系。结果表明：①两种不同程度的脊髓损伤均可造成大鼠脊髓ＳｐＥＰ，ＣＭＥＰ的明显变化，尤以ＳｐＥＰ变化明显。损伤越重，电位改变越明显．②在脊髓损伤后１～２４小时内，伤后１０分钟ＳｐＥＰ，ＣＭＥＰ波幅却有明显降低，４～８小时进一步降低。两次降低有明显差异。ＳｐＥＰ峰潜伏时延长，以４～８小时显著。表明原发损伤后在受损部位存在继发性损伤，提示阻止继发损伤的时间应早于伤后４小时，并尽可能提前。     

大鼠脊髓压迫损伤后COX-2基因和蛋白的表达

目的观察大鼠脊髓压迫损伤后COX-2mRNA和蛋白在脊髓组织内表达的时间特征,以及COX-2的空间分布特点。方法以压迫装置致脊髓损伤后,在伤后不同时间点(30min、3h、6h、24h、72h、1w)分别应用RT-PCR、Western blotting、免疫组化技术检测COX-2mRNA和蛋白表达和分布。结果RT-PCR和Western blotting显示,COX-2mRNA和蛋白伤后30min表达开始增加,于伤后6h达到峰值,伤后1w表达接近基础水平。免疫组化提示,COX-2蛋白在假手术组表达仅见于脊髓血管内皮细胞,伤后COX-2蛋白表达见于损伤区附近脊髓灰质内的神经元和血管内皮细胞,损伤中心部位COX-2免疫阳性细胞少见。结论脊髓压迫损伤早期可快速诱导COX-2基因的表达上调和蛋白的合成,伤后COX-2蛋白分布发生变化,主要位于脊髓神经元和血管内皮细胞。     

The Effects of Age on the Morphometry of the Cervical Spinal Cord and Spinal Column in Adult Rats: An MRI‐Based Study

Rat models are commonly used to investigate the pathophysiological pathways and treatment outcomes after spinal cord injury (SCI). The high incidence of fall‐induced SCI in older adults has created a need for aging models of SCI in rats to investigate potential age‐related differences in SCI severity and outcomes. The aims of this study were to determine the influences of age and vertebral level on the geometries of the cervical spinal cord and spinal column in a rat model. Three young (3 months) and three aged (12 months) Fischer 344 rats were imaged in a high field (7 T) small‐animal magnetic resonance imaging system. All spinal cord geometry variables (including depth, width, and axial cross‐sectional area) and one spinal canal variable (depth) were significantly larger in the aged specimens by an average of 8.1%. There were main effects of vertebral level on all spinal cord variables and four spinal canal variables with values generally larger at C4 as compared to C6 (average increases ranged from 5.7% to 12.9% in spinal cord measures and 5.4% to 6.8% in spinal canal measures). High inter‐rater reliability between two measurers was observed with a mean intraclass correlation of 0.921 and percent difference of 0.9% across all variables measured. This study clearly demonstrates that cervical spinal cord geometry changes between the ages of 3 and 12 months in Fischer 344 rats. This information can aid in the planning and interpretation of studies that use a rat model to investigate the influence of age on cervical SCI. Anat Rec, 297:1885–1895, 2014. © 2014 Wiley Periodicals, Inc.     

外加电场对实验性大鼠脊髓损伤作用的研究

目的:探讨脊髓损伤后外加电场(electric fields,EF)对脊髓血流量(spinal cord blod flow,SCBF)及神经功能的影响。方法:Wistar大鼠20只,随机分为对照组(CON组)和EF治疗组(EF组)。Allen's打击法50 gcm(5 g×10 m)致伤大鼠L1～L2段脊髓,给予EF治疗,于伤前、伤后即刻、1、3、6、24 h分别记录T12段脊髓血流量、脊髓感觉诱发电位。术后7、14天行联合行为评分(CBS)。结果:与盐水对照组比较,应用EF后,大鼠SCBF、SEP明显优于CON组(P<0.05)。结论:EF能有效改善损伤早期脊髓微循环,保护脊髓神经功能。     

Therapeutic Effect of Curcumin and Methylprednisolone in the Rat Spinal Cord Injury

In addition to imperiling an individual's daily life, spinal cord injury (SCI), a catastrophic medical damage, can permanently impair an individual's body function. Methylprednisolone (MP), a medically accepted therapeutic drug for SCI, is highly controversial for the lack of consensus on its true therapeutic effect. In recent years, curcumin has served as a potential and novel therapeutic drug in SCI. Our study was intended to investigate the precise effect of MP and curcumin in SCI. We examined the function of MP and curcumin in a SCI model rat, both in vivo and in vitro, and found that there was a momentous improvement in Basso‐Beattie‐Bresnahan scores in the MP‐treated group when compared with Cur‐treated group within 14 days. Results obtained from the histological, immunohistochemistry and ultrastructural examinations evidenced the curative effect of MP was better than curcumin before Day 14. Nonetheless, there was a significant variation in the treatment effect between the MP‐treated and Cur‐treated groups after 14 days. The curcumin's effectiveness was more obvious than MP after 14 days following SCI. As such, we surmise that curcumin has a better therapeutic potential than MP with a prolong treatment time in the wake of SCI. Anat Rec, 301:686–696, 2018. © 2017 Wiley Periodicals, Inc.     

Arterial Blood Supply to the Spinal Cord in Animal Models of Spinal Cord Injury. A Review

Animal models are used to examine the results of experimental spinal cord injury. Alterations in spinal cord blood supply caused by complex spinal cord injuries contribute significantly to the diversity and severity of the spinal cord damage, particularly ischemic changes. However, the literature has not completely clarified our knowledge of anatomy of the complex three‐dimensional arterial system of the spinal cord in experimental animals, which can impede the translation of experimental results to human clinical applications. As the literary sources dealing with the spinal cord arterial blood supply in experimental animals are limited and scattered, the authors performed a review of the anatomy of the arterial blood supply to the spinal cord in several experimental animals, including pigs, dogs, cats, rabbits, guinea pigs, rats, and mice and created a coherent format discussing the interspecies differences. This provides researchers with a valuable tool for the selection of the most suitable animal model for their experiments in the study of spinal cord ischemia and provides clinicians with a basis for the appropriate translation of research work to their clinical applications. Anat Rec, 300:2091–2106, 2017. © 2017 Wiley Periodicals, Inc.     

电磁场在组织工程修复脊髓损伤中应用

目的：总结电磁场在组织工程修复脊髓损伤中应用进展。方法：应用计算机检索CNKI 1990年1月至2008年4月有关电磁场在组织工程修复脊髓损伤方面的文章，检索词“电磁场，脊髓损伤，组织工程”，限定文献语言种类为中文。同时计算机检索Medline1990年1月至2008年4月有关电磁场在组织工程修复脊髓损伤方面的文章，检索词“electromagnetic fields，spinal cord injury，tissue engineering”，限定文献语言种类为English。对资料进行初审。选取电磁场在组织工程修复脊髓损伤方面的相关文献，查找全文，对文献分析，总结研究内容。结果：电磁场在组织工程修复脊髓损伤中作用机制包括如下：电磁场可通过上调Ca（v）通道的活性，促进神经发育和分化，经颅脑磁刺激可以促进室管膜周围神经经细胞形成，低频电磁场也直接影响细胞间缝隙联接，参与细胞间信息调控。结论：将电磁场用于组织工程修复脊髓损伤，有利于脊髓功能修复。     

大鼠胎脑移植对急性脊髓损伤的组织修复作用

目的　为了减轻宿主急性脊髓损伤的继发性病理改变 ,使移植的胎脑细胞能更好地存活、分化 ,与宿主脊髓组织整合 ,以替代受损或变性坏死的神经元。方法　用妊娠 13天的大鼠胎脑为移植物 ,采用细胞悬液立体慢速注射法 ,依脊髓损伤类型移植于脊髓白质不同部位。进行光电镜观察。结果　①单纯脊髓损伤后 ,损伤脊髓发生出血 ,变性坏死 ,液化呈囊腔 ,最终形成胶质瘢痕 ;②损伤后早期移植胎脑悬液后明显减轻了继发性病理改变 ,减轻胶质瘢痕的形成 ;③依造成的后脊髓损伤类型进行的按损伤部位移植 ,胎脑细胞80 %存活 ,分化 ,并与宿主脊髓组织整合 ,形成了多种类型的突触及器官样分化 ,构成“中继”的形态学所见。结论　按损伤部位移植的方法能较大程度地保留损伤区残存的神经组织 ,避免损伤脊髓遭受第二次损伤 ,尤其是脊髓灰质     

Clenbuterol，β_2-肾上腺素能受体激动剂促进成年大鼠脊髓半横切后红核脊髓束轴突再生和运动功能的恢复

目的研究Clenbuterol对于促进脊髓半横切(SCI)后轴突再生和运动功能恢复的功效。方法成年Wistar大鼠(n=10-12)接受硬脊膜内的第7颈段脊髓单侧半横切显微手术。Clenbuterol以9 mg/L的剂量加入饮用水中,而对照组未给予任何治疗。采用Cylinder试验和患肢抓力试验观察运动功能的恢复状况。行为学观察期(6周)结束后,大鼠接受第二胸段脊髓处椎板切开术,4%Fluorogold微量注射进入红核脊髓束,一周后被处死。结果运动功能逐渐恢复,从SCI后第3周开始,Clenbuterol治疗组显著优于对照组(最终患肢抓力:403.45±19.82g vs 335.13±13.48g,p<0.05);在Cylinder试验中,双侧前肢共同使用触壁的百分比,Clenbuterol组显著高于对照组(43.39%±5.85%vs 19.42%±6.61%,p<0.05)。Clenbuterol治疗显著地降低了SCI后继发性组织损伤,提高了pCREB阳性细胞核在整个SCI点的表达水平。与对照组相比,Clenbuterol显著地促进了红核脊髓束轴突的再生。结论脊髓损伤后,Clenbuterol可促进离断的轴突再生以及运动功能的恢复。     

有限元分析法在脊髓损伤生物力学中的研究进展

脊髓损伤时的变化非常复杂,动物模型很难精确模拟损伤环境以及测量局部组织的生物力学属性,而有限元模型则可以通过分析脊髓组织的应力和应变分布,从生物力学角度为脊髓损伤的病理研究和治疗提供一个更为高效的方法。目前,有限元模型已被广泛应用,并与动物实验模型相辅相成。本文回顾了有限元法在脊髓损伤中的研究进展,对有限元法在脊髓本体建模、脊髓损伤的生物力学行为及其临床应用等方面的研究现况进行归纳及总结,以期为临床脊髓损伤问题提供更为全面的理论参考。     

顺铂联合放射治疗对大鼠脊髓损伤影响的观察

目的探讨顺铂(c isp latin,DDP)联合放射治疗对大鼠脊髓损伤的影响。方法40只W istar大鼠随机分为5组,即空白组、单纯化疗组、单纯放射组、先化后放组和先放后化组。单化组单次腹腔注射顺铂5 mg/kg。单放组和放化联合组采用瓦里安2300 C/D直线加速器6M eV电子线照射大鼠胸段脊髓,照射野为2 cm×4 cm,5Gy/次,隔日1次,总剂量为40 Gy。联合组顺铂与照射的间隔时间为3天。照射结束后5个月,行活体灌注固定,取材,光镜和电镜观察脊髓的形态学变化。结果光镜下,CT组灰质未见改变,白质内部分有髓神经纤维排列紊乱,部分髓鞘板层结构松解、扭曲。RT组灰质未见改变,白质出现部分水肿坏死,髓鞘板层模糊不清。CT+RT组脊髓灰质、白质改变明显,其中CT+放疗组的灰质内可见到明显的神经元核变成细长形,尼氏体数量减少,白质出现大片坏死。电镜下,CT组髓鞘结构出现轻度变化,表现为部分髓鞘的板层结构松解、扭曲。RT组脊髓损伤表现为板层结构水肿、粘连,模糊不清。CT+RT组的脊髓损伤程度严重,表现为正常髓鞘的板层结构完全消失,轴突及神经纤维裸露,血管增生,部分血管内皮细胞坏死。RT+CT组脊髓损伤表现为正常髓鞘的板层结构部分松解、扭曲、断裂。结论顺铂与放疗联用明显加重脊髓损伤,且放疗前加用顺铂脊髓损伤加重。     

促红细胞生成素治疗急性脊髓损伤的临床研究

目的 分析大剂量甲强龙联合促红细胞生成素治疗急性脊髓损伤患者的临床疗效。方法 选取2016年1月~2017年6月就诊于我院骨科的56例ASCI患者,采用控制主要因素的分层随机化分组法和简单随机分组法,将患者分为观察组与对照组,每组26例,观察组给予MP+EPO治疗,对照组给予MP治疗,并在患者收治入院时及治疗后1、6个月,严格按照ASIA评分标准,对患者的脊髓神经功能进行评定,并记录并发症情况。结果 与入院时相比,治疗后1月及6个月两组患者ASIA评分提高,差异有统计学意义(P＜0.05), 且观察组高于对照组,差异有统计学意义(P＜0.05)。两组患者并发症比较,差异无统计学意义（P＞0.05）。结论 MP冲击疗法联合EPO治疗ASCI比单用MP治疗效果更佳,EPO能有效促进ASCI患者的神经功能恢复。     

大鼠脊髓损伤继发骨质疏松生物力学性质实验研究

研究了正常大鼠骨和脊髓损伤所致大鼠骨质疏松骨的生物力学性质。选用280g～320g4月～5月龄Wistar雄性大鼠70只，随机分为0周空白对照组10只，3周对照组10只，7周对照组10只，11周对照组10只，三周实验组10只，7周实验组10只，11周实验组10只，0周空白组于0周处死，解剖取大鼠股骨、胫骨、肱骨，以生理盐水浸温的纱布包裹，置-20℃冰箱内保存备用。对3周、7周、11周对照组大鼠以咬骨钳将其椎板咬开，不破坏硬膜和脊髓，进行饲养。对3周、7周、11周实验组大鼠人为造成脊髓损伤后饲养，复制骨质疏松模型。分别于3周、7周、11周处死对照组和实验组大鼠。取0周空白组和11周实验组胫骨制作脱钙切片进行骨组织形态观察。 取大鼠股骨进行弯曲实验，取肱骨进行拉伸实验，取胫骨进行冲击实验。取0周空白组、3周实验组、7周实验组、11周实验组大鼠股骨进行应力松弛、蠕变实验，得出了各组大鼠肱骨拉伸力学性能指标、各组大鼠股骨弯曲力学性能指标，各组大鼠胫骨冲击性能指标和大鼠股骨0周，3周、7周、11周对照组大鼠股骨应力松驰、蠕变数据及曲线。实验结果表明，模型组和对照组的各项力学性能指标显著低于0周空白组（P〈0．05）。对脊髓损伤导致大鼠骨质疏松对骨力学性能指标的影响进行分析讨论。     

Cellular Neuroinflammation in a Lateral Forceps Compression Model of Spinal Cord Injury

Postinjury inflammation has been implicated in secondary degeneration following injury to the spinal cord. The cellular inflammatory response to injury has not been described in the lateral compression injury model, although various types of compression injuries account for ～20% of human spinal cord injuries (SCI). Here, we used forceps to induce a moderate compression injury to the thoracic spinal cord of female Sprague‐Dawley rats. We evaluated innate and adaptive components of the inflammatory response at various times postinjury using immunohistochemical techniques. We show that components of innate immunity (e.g., macrophages and dendritic cells) peak between 1 and 2 weeks postinjury but persist through 42 days postinjury (dpi). CD163 and CD206 expression, associated with an anti‐inflammatory, reparative phenotype, was upregulated on activated macrophages in the injury site, as were MHC class II antigens. The expression of MHC class II antigens is necessary for the initiation of adaptive immunity and was accompanied by an influx of T cells. T cells were initially restricted to gray matter at the injury epicenter but were later observed throughout the lesioned parenchyma. In summary, we demonstrate that lateral forceps compression of the spinal cord produces a neuroinflammatory response similar to that described in human spinal cord trauma and in other experimental models of spinal cord trauma, thus is an appropriate model to study secondary neurodegeneration in SCI. Anat Rec, 2013. © 2013 Wiley Periodicals, Inc.     

Spatio‐Temporal Development of Axonopathy in Canine Intervertebral Disc Disease as a Translational Large Animal Model for Nonexperimental Spinal Cord Injury

Spinal cord injury (SCI) represents a devastating central nervous system disease that still lacks sufficient therapies. Here, dogs are increasingly recognized as a preclinical animal model for the development of future therapies. The aim of this study was a detailed characterization of axonopathy in canine intervertebral disc disease, which produces a mixed contusive and compressive injury and functions as a spontaneous translational animal model for human SCI. The results revealed an early occurrence of ultrastructurally distinct axonal swelling. Immunohistochemically, enhanced axonal expression of β‐amyloid precursor protein, non‐phosphorylated neurofilament (n‐NF) and growth‐associated protein‐43 was detected in the epicenter during acute canine SCI. Indicative of a progressive axonopathy, these changes showed a cranial and caudally accentuated spatial progression in the subacute disease phase. In canine spinal cord slice cultures, immunoreactivity of axons was confined to n‐NF. Real‐time quantitative polymerase chain reaction of naturally traumatized tissue and slice cultures revealed a temporally distinct dysregulation of the matrix metalloproteinases (MMP)‐2 and MMP‐9 with a dominating expression of the latter. Contrasting to early axonopathy, diminished myelin basic protein immunoreactivity and phagocytosis were delayed. The results present a basis for assessing new therapies in the canine animal model for translational research that might allow partial extrapolation to human SCI.     

Spinal Cord Injury Causes More Damage to Fracture Healing of Later Phase than Ovariectomy in Young Mice

The purpose of this study was to compare the effects of spinal cord injury (SCI) and ovariectomy (OVX) on femoral fracture healing of later phase in young mice. Sixty young female C57 mice were randomized into three groups: SCI, OVX, and age-matched intact control. The femoral fracture was generated at 3 weeks after SCI or OVX. At 1 month after fracture, the femoral fracture area was evaluated through the healing status using radiograph; bone mineral density using dual X-ray absorptometry; callus formation and mineralization and neovascularization in callus using micro-computed tomography; biomechanical analysis using testing machine; and histology analysis by staining with hematoxylin-eosin stain. SCI mice showed lower bone mineral density in the femoral callus as compared with OVX mice. Callus geometric microstructural parameters of the femora in SCI mice were significantly lower than OVX mice. SCI induced significant changes of biomechanical parameters in the femoral fracture healing area. The callus formation and callus neovascularization in SCI mice were significantly lower than in OVX mice. SCI induces more deterioration of fracture healing in the femoral diaphysis than OVX.     

Derivation of Specific Neural Populations From Pluripotent Cells for Understanding and Treatment of Spinal Cord Injury

Due to the nature of the biological response to traumatic spinal cord injury, there are very limited therapeutic options available to patients. Recent advances in cell transplantation have demonstrated the therapeutic potential of transplanting supportive cell types following spinal cord injury. In particular, pluripotent stem cell derived neural cells are of interest for future investigation. Use of pluripotent stem cells as the source allows many cell types to be produced from a population that can be expanded in vitro. In this review, we will discuss the signaling pathways that have been used to differentiate spinal neural phenotypes from pluripotent stem cells. Additionally, we will highlight methods that have been developed to direct the differentiation of pluripotent stem cells to specific neural fates. Further refinement and elaboration of these techniques might aid in elucidating the multitude of neuronal subtypes endogenous to the spinal cord, as well as produce further therapeutic options for spinal cord injury recovery. Developmental Dynamics 248:78–87, 2019. © 2018 Wiley Periodicals, Inc.     

Functional and Histological Improvement of the Injured Spinal Cord Following Transplantation of Schwann Cells Transfected With NRG1 Gene

In this study, we implanted Schwann cells (SCs) transfected with Neuregulin 1 (NRG1) gene into rats with hemisection spinal cord injury, determined its effects on the repair of spinal cord injury and investigated the underlying mechanisms. Primary SCs were cultured, purified, and transfected with NRG1 gene. SCs and SCs transfected with NRG1 gene were implanted, respectively, into rats with hemisection spinal cord injury. Behavior, imaging, electrophysiology, and immuno‐histological analyses were performed to evaluate the effect of NRG1 gene‐transfected SCs on the repair of spinal cord injury. In vitro studies showed that NRG1 protein was highly expressed in SCs transfected with NRG1 gene. In addition, the receptors for NRG1, ErbB2, and ErbB4, were upregulated in a time‐dependent manner. NRG1‐transfected SCs secreted large amount of NRG1 proteins in vivo, which efficiently promoted the expression of ErbB2 and ErbB4 in the neurons and neuroglia cells. Moreover, the number of NSE‐ and GFAP‐positive cells was increased. After cell transplantation, many transplanted cells survived and migrated to the areas with spinal cord injuries. The injuries were recovered in all the experimental groups, but the most significant recovery was observed in the group of rats implanted with SCs transfected with NRG1 gene. We conclude that NRG1‐transfected SCs can significantly increase the effect on the repair of spinal cord injury. This repair effect is achieved via the upregulation of ErbB receptor in the target cells, increased proliferation of glial cells, and protection of neurons from apoptosis. Anat Rec, 2010. © 2010 Wiley‐Liss, Inc.