脊髓完全横断性损伤修复的研究进展

脊髓神经移植以及神经生长因子 ,一直是修复外伤性脊髓完全横断性损伤的主要研究方向。随着基因工程的问世 ,人们开始研究联合应用基因转移技术治疗中枢神经系统损伤。基因治疗外伤性脊髓完全横断性损伤就是将转基因技术和目前研究较多的胚胎脊髓移植、外周神经脊髓移植等结合起来 ,让局部释放的神经营养因子不断刺激和引导宿主纤维与移植物的整合和联系 ,从而促进脊髓损伤的修复。     

神经节苷脂联合甲基强的松龙早期治疗急性脊髓损伤疗效分析

目的 探讨早期应用神经节苷脂联合甲基强的松龙治疗急性脊髓损伤的疗效.方法 回顾性分析我科2008-01-2011-12收治的31例急性脊髓损伤患者的临床资料,均未行手术治疗,随机分为2组,甲基强的松龙组（MP组）17例采用甲基强的松龙治疗,神经节苷脂＋甲基强的松龙组（GM1＋MP组）14例在应用甲基强的松龙的同时,联合应用神经节苷脂治疗.结果 GM1＋MP组临床疗效优于MP组（P＜0.05）.结论早期给予神经节苷脂联合甲基强的松龙治疗能有效促进脊髓功能恢复,降低致残率,显著改善患者生活质量.     

纳洛酮联合神经节苷脂治疗急性脊髓损伤的疗效观察

目的探讨纳洛酮联合神经节苷脂治疗急性不完全脊髓损伤的疗效。方法以2012-12—2014-12我院接诊的80例急性脊髓损伤的患者为研究对象。以患者入院先后顺序分为常规组和联合组各40例。常规组采取一般治疗,联合组采用纳洛酮联合神经节苷脂治疗,对比2组临床疗效。结果治疗后神经功能评分痛觉和触觉评分联合组均高于常规组,常规组的运动功能神经远远低于联合组,2组差异有统计学意义(P=0.0000,t=5.818 9)。常规组总有效率50%,联合组总有效率100%,差异有统计学意义(χ~2=3.888 9,P=0.048 6)。结论纳洛酮联合神经节苷脂能够促进脊髓损伤后的痛觉、触觉和运动功能神经的恢复,治疗效果显著,值得推广。     

半乳糖凝集素-1对急性脊髓损伤模型大鼠的保护作用及其机制

目的研究半乳糖凝集素-1(Galectin-1)对大鼠急性脊髓损伤的保护作用及其机制。方法 45只SPF级SD大鼠随机平均分为Galectin-1组、甲泼尼龙(MP)组和生理盐水对照组(生理盐水组)。以Allen's法打击脊髓造模,分别在术后1 d、7 d、14 d每组各取5只大鼠,先做BBB评分及斜板试验,然后处死大鼠取损伤处脊髓组织进行苏木精-伊红(HE)染色及胶质纤维酸性蛋白(GFAP)免疫组化染色检测,同时用酶联免疫吸附测定(ELISA)法检测血清白细胞介素-10(IL-10)的含量。结果术后1 d,3组大鼠BBB评分、斜板试验结果及血清IL-10含量的差异无统计学意义(均P0.05);术后7 d、14 d,MP组和Galectin-1组的BBB评分、斜板试验结果及血清IL-10含量均较生理盐水组高(均P0.05),而MP组与Galectin-1组之间的差异均无统计学意义(均P0.05)。HE染色显示术后各时间点,Galectin-1组和MP组脊髓损伤肿胀及出现核固缩或解离神经元的数量少于生理盐水组。术后1 d,3组大鼠脊髓星形胶质细胞(GFAP表达阳性)数量无明显区别;术后7 d、14 d,Galectin-1组及MP组明显多于生理盐水组,而Galectin-1组与MP组则无明显差别。结论Galectin-1对大鼠急性脊髓损伤具有一定的保护作用,其机制可能是通过增强机体IL-10的表达,从而抑制损伤后的炎症反应而发挥脊髓保护作用的。     

神经节苷脂GM1对弥漫性轴索损伤疗效的临床观察

目的 对单唾液酸四己糖神经节苷脂(GM_1)在弥漫性轴索损伤(DAI)患者中的应用效果进行临床初步观察。方法26例DAI患者,分为GM_1治疗组(n=13)和常规综合治疗组(n=13),观察治疗后患者生命体征、头颅CT或MRI变化、意识转归、GCS变化和GOS评分情况。结果 GM_1治疗组患者意识清醒快(接受GM_1治疗后平均7.56d);GCS和GOS评分,GM_1组也明显好于对照组(P<0.05)。结论 GM_1对DAI患者的神经功能康复起到了明显的、肯定的作用。     

聚乳酸-乙醇酸支架移植对脊髓半横断损伤大鼠后肢运动能力和运动诱发电位的影响

目的 观察聚乳酸-乙醇酸（Poly-Lactic-co-glycolicacid,PLGA）支架对脊髓半横断损伤大鼠后肢运动功能的影响。方法 雌性成年Wistar大鼠随机分为正常组（n=15）、假手术组（n=15）、脊髓半横断（hemisectedspinal cord injury,hSCI）组（n=15）和脊髓半横断移植PLGA（PLGA）组（n=15）,术后进行行为学评分：BBB评分（Basso Beattie Bresnahan locomotor rating scale）和斜板（inclined plane,IP）试验,并观察皮层运动诱发电位（motor evoked ptentials,MEPs）的改变。结果 第4周时PLGA组BBB评分高于hSCI组（7.9±1.2 vs 7.1±1.3,P =0.042）;在第4、8周时PLGA组IP评分高于hSCI组（56.0±2.0 vs 54.7±2.3,P =0.030;64.7±2.4 vs 62.3±2.3,Ｐ＝0.038）;在第12周时PLGA组MEPs波幅高于hSCI组（29.9±11.0μV vs 21.4±10.4μV,P =0.039）。结论 PLGA支架移植能促进脊髓半横断损伤大鼠后肢运动功能和电生理功能的恢复。     

控释GDNF联合MSCs源神经元样细胞移植对猴脊髓损伤后前角运动神经元及bcl-2/bax表达的影响

目的 探讨GDNF与MSCs源性神经元样细胞联合移植对猕猴脊髓损伤后前角运动神经元的协同保护作用及机制.方法 取12例治疗猕猴脊髓损伤相关的石蜡标本(3组,4例/组),应用光镜统计前角运动神经元数量;应用免疫组化方法及图像分析系统观察bcl-2、bax蛋白表达情况.结果 治疗组前角运动神经元数量均明显高于对照组,并且联合移植组数量高于单纯细胞移植组(P<0.01).联合移植组bcl-2蛋白平均吸光度值高于单纯细胞移植组(P<0.05);Bax蛋白平均吸光度值在两治疗组间表达的差异无统计学意义.结论 联合移植组对猕猴脊髓损伤后前角运动神经元的保护作用更佳,可能与GDNF促进前角运动神经元bcl-2蛋白表达增强有关.     

肾源性细胞因子促红细胞生成素对急性脊髓损伤大鼠细胞凋亡的影响**★

目的：促红细胞生成素为肾源性细胞因子，在大鼠急性脊髓损伤后对脊髓神经功能具有保护作用。实验拟证明不同时间硬膜外腔注射后其对脊髓神经细胞凋亡的影响。 方法：实验于2007-01/04在苏州大学附属第二医院动物实验室完成。①实验材料：清洁级成年雄性SD大鼠48只，体质量(270 ±10) g；实验用人重组促红细胞生成素为日本麒麟啤酒株式会社制造，规格3 000 IU /支。②实验分组及处理：将大鼠随机分为正常组6只，假手术组6只（仅切除椎板），生理盐水组18只，实验组18只。按改良Allen打击法建立大鼠脊髓不完全损伤模型。实验组分别于大鼠脊髓损伤后1，6，24 h（每个时间点6只），于硬膜外腔注射重组人促红细胞生成素5 000 u/（kg?bw）；生理盐水组于相同时间予以相同体积生理盐水。③实验评估：通过动物神经运动功能BBB评分及斜板试验评价神经损伤程度；苏木精－伊红染色法观察组织学改变，并采用原位末端标记法标记法检测脊髓神经细胞凋亡数。 结果：①神经行为学评分：正常组、假手术组大鼠双下肢运动功能正常；与生理盐水组相比,脊髓损伤后实验组1,6及24 h神经运动功能有改善；斜板角度及BBB评分均明显提高，差别有显著性意义(P < 0.05)。②组织学苏木精－伊红染色结果：实验组组织学破坏改变明显较生理盐水组轻。③凋亡神经细胞及计数结果：实验组脊髓神经细胞凋亡指数均明显下降，差异有显著性(P < 0.05)。 结论：早期应用外源性促红细胞生成素对脊髓不完全损伤后引起的神经运动功能损害具有保护作用,能明显改善脊髓损伤后的临床功能表现。此种保护作用与促红细胞生成素能够抑制神经细胞凋亡有关。     

CXCL12/CXCR4生物学轴对骨髓间充质干细胞修复脊髓损伤的影响☆

背景：研究发现不同途径移植骨髓间充质干细胞均能向脊髓损伤部位迁移,进而发挥治疗作用。 目的：探讨CXCL12/CXCR4生物学轴对骨髓间充质干细胞趋向脊髓损伤部位迁移的作用。 方法：采用改进的脊椎骨破坏法制备脊髓损伤模型。假手术组只打开皮肤,不损伤脊髓且不作任何干预;模型组于造模后第2天采用腰骶鞘内注射5 μL生理盐水;细胞移植组于造模后第2天采用腰骶鞘内移植5 μL骨髓间充质干细胞。 结果与结论：①荧光显微镜下可见,横切的脊髓损伤局部有大量的标记细胞聚集,而在损伤部位远端1 cm处,仅见少量的标记骨髓间充质干细胞。②骨髓间充质干细胞表达中等水平的趋化因子CXCL12,其特异性结合受体CXCR4也有低水平表达。③脊髓损伤7 d后,局部CXCL12表达增强,主要集中在脊髓损伤部位的皮质区域,而在损伤部位1 cm以外的脊髓组织未见大量表达的CXCL12。CXCR4蛋白表达没有明显的时间效应。④检测CXCL12 mRNA的转录水平发现细胞移植组的CXCR4转录水平明显高于假手术组和模型组,损伤后14 d脊髓损伤局部CXCL12的转录水平最强,21 d时降低,CXCL12的局部转录水平明显高于远端。⑤脊髓损伤部位也表达趋化因子CXCR4,但其表达水平没有时程差异。损伤局部的CXCR4转录水平略高于远端,但差异无显著性意义。说明CXCL12/CXCR4生物学轴参与骨髓间充质干细胞向脊髓损伤区域迁移。     

PLGA-Nogo A抗体缓释微球对大鼠脊髓损伤神经再生的影响

BACKGROUND： Nogo A antigen is the major inhibiting factor blocking regeneration of the injured spinal cord. Neutralizing Nogo A antigens using Nogo A antibodies may help promote neurite regeneration and nervous function recovery. For successful regeneration, sustained release of the antibody from a biodegradable material loaded with Nogo A antibodies to the injury site is required. OBJECTIVE： To compare the therapeutic effects of poly lactic-co-glycolic acid （PLGA）-Nogo A antibody delayed-release microspheres and Nogo A antibody alone on spinal regeneration in Sprague-Dawley rats with complete transverse injury to the spinal cord. DESIGN, TIME AND SETTING： A randomized, controlled animal trial was performed at the Pharmacological Laboratory of West China Center of Medical Sciences, Sichuan University, between October 2007 and January 2008. MATERIALS： Goat anti-rat Nogo A monoclonal antibody was purchased from Santa, American; goat anti-rat neurofilament 200 monoclonal antibody was from Zhongshan Goldenbridge, Beijing, China; PLGA-Nogo A antibody delayed-release microspheres were provided by the College of Pharmacy, Sichuan University. METHODS： A total of 36 adult female Sprague Dawley rats were used to establish models of completely transected spinal cord injury, at T10. Animals were randomly divided into three groups （n=12）： model, Nogo A antibody alone, and Nogo A antibody delayed-release microsphere groups. After transverse injury of the spinal cord, 50 μ L normal saline solution, 50 μL normal saline solution containing 50μL g Nogo A antibody, and 50 μL normal saline solution containing 50 μg Nogo A antibody microspheres were administered to the respective groups at the injury site. MAIN OUTCOME MEASURES： The expression of Nogo A and neurofilament 200 in injured spinal cord was tested immunohistochemically, and motor function of rats was assessed by Basso-Beattie-Bresnahan （BBB） locomotor rating scale. RESULTS： Four weeks after injury, expression of Nogo A in microsphere group was significantly less than model and Nogo A antibody alone groups （P 〈 0.05）; while there was no significant difference between model and Nogo A antibody alone groups （P 〉 0.05）. Ten weeks after injury, microsphere group showed a significantly greater expression of neurofilament 200 than model and Nogo A antibody alone groups （P 〈 0.05）; while no significant difference was found between model and Nogo A antibody alone groups （P 〉 0.05）. At postoperative weeks 5 and 6, the score of BBB locomotor rating scale in microsphere group was significantly greater than the model group （P 〈 0.05）, and at postoperative weeks 7 10, the score was much greater than model and Nogo A antibody alone groups （P 〈 0.05）. CONCLUSION： Nogo A antibody delayed-release microspheres decreased Nogo A expression, increased neurofilament 200 expression in the injured spinal cord of rats, and promoted recovery of motor function through sustained drug release over a long-term period.     

Effects of Jisuikang on hemorheology and inflammatory factors in rats following spinal cord injury

BACKGROUND: Trauma can damage the spinal cord or cauda equina to different degrees. Previous studies have verified that traditional Chinese medicine has effects on spinal cord injury via a variety of pathways. OBJECTIVE: To observe changes in hemorheology and inflammatory factors in spinal cord injury rats following treatment with the Chinese medicine Jisuikang, to verify the dose-dependent effect of Jisuikang, and to compare its effects with the effects of prednisone. DESIGN, TIME AND SETTING: A randomized study was performed at the Research Institute of Orthopedics, and Experimental Center of First Clinical Medical College, Nanjing University of Traditional Chinese Medicine, China from September 2007 to March 2008. MATERIALS: Jisuikang powdered extract, composed of milkvetch root (30 g), Chinese angelica (12 g), red peony root (12 g), earthworm (10 g), szechwan lovage rhizome (10 g), peach seed (10 g) and safflower (10 g), was provided by the Experimental Center, First Clinical Medical College, Nanjing University of Traditional Chinese medicine. Each gram of powdered extract was equivalent to 6.47 g crude drug. METHODS: A total of 72 Sprague Dawley rats were randomly assigned into 6 groups (n = 12). Rat models of spinal cord injury were established using the occlusion method. Rats in the model group were treated with distilled water. Rats in the 25 g/kg, 12.5 g/kg, and 6.25 g/kg Jisuikang groups were given 25 g/kg, 12.5 g/kg, or 6.25 g/kg Jisuikang by gavage, for 14 days. Rats in the prednisone group received 0.06 g/kg prednisone by gavage, for 7 days. Rats in the normal group were given the same volume of distilled water. The volume of administration was 15 mL/kg.MAIN OUTCOME MEASURES: Rat serum interleukin-10, tumor necrosis factor-α (TNF-α), nitric oxide, nitric oxide synthase levels, malondialdehyde content, superoxide dismutase activity and whole blood viscosity were measured in each group. Spinal cord around the site of the model was collected. Half the spinal cord was used for histopathologic examination. The other half was used for measurement of nitric oxide and NOS levels, malondialdehyde contents, and superoxide dismutase activity. RESULTS: Superoxide dismutase activity was higher in the 25 g/kg Jisuikang group than in the model group. Malondialdehyde contents, nitric oxide and NOS levels were lower in the 25 g/kg and 12.5 g/kg Jisuikang groups compared with the model group. Whole blood viscosity was lower in the 25 g/kg and 12.5 g/kg Jisuikang groups compared with the model group (P < 0.05-0.01). Serum TNF-α content was lower in each Jisuikang group compared with the model group (P < 0.05-0.01). Serum interleukin-10 levels were greater in the prednisone group and each Jisuikang group compared with the model group (P < 0.01). Mild hemorrhage and necrosis in the rat spinal cord, and unclear neural cell swelling were seen in the 25 g/kg Jisuikang group. Severe hemorrhage and necrosis in the rat spinal cord, and distinct neural cell swelling were seen in the 12.5 g/kg Jisuikang group. Edema in the white matter was found in the 6.25 g/kg Jisuikang group. Pathological changes in the prednisone group were identical to the 25 g/kg and 12.5 g/kg Jisuikang groups. CONCLUSION: Jisuikang inhibits nitric oxide synthase expression, reduces nitric oxide and TNF-α levels, decreases malondialdehyde content, increases interleukin-10 levels and superoxide dismutase activity, improves indices of hemorheology, and prevents secondary changes in spinal cord injury, resulting in relieving pathological changes in spinal cord tissue. The outcome was significant in the 25 g/kg Jisuikang group compared with the 12.5 g/kg Jisuikang group.     

Effects of Jisuikang on hemorheology and inflammatory factors in rats following spinal cord injury*☆

BACKGROUND： Trauma can damage the spinal cord or cauda equina to different degrees. Previous studies have verified that traditional Chinese medicine has effects on spinal cord injury via a variety of pathways. OBJECTIVE： To observe changes in hemorheology and inflammatory factors in spinal cord injury rats following treatment with the Chinese medicine Jisuikang, to verify the dose-dependent effect of Jisuikang, and to compare its effects with the effects of prednisone. DESIGN, TIME AND SETTING： A randomized study was performed at the Research Institute of Orthopedics, and Experimental Center of First Clinical Medical College, Nanjing University of Traditional Chinese Medicine, China from September 2007 to March 2008. MATERIALS： Jisuikang powdered extract, composed of milkvetch root （30 g）, Chinese angelica （12 g）, red peony root （12 g）, earthworm （10 g）, szechwan lovage rhizome （10 g）, peach seed （10 g） and safflower （10 g） was provided by the Experimental Center, First Clinical Medical College, Nanjing University of Traditional Chinese medicine. Each gram of powdered extract was equivalent to 6.47 g crude drug. METHODS： A total of 72 Sprague Dawley rats were randomly assigned into 6 groups （n = 12）. Rat models of spinal cord injury were established using the occlusion method. Rats in the model group were treated with distilled water. Rats in the 25 g/kg, 12.5 g/kg, and 6.25 g/kg Jisuikang groups were given 25 g＆g, 12.5 g/kg, or 6.25 g/kg Jisuikang by gavage, for 14 days. Rats in the prednisone group received 0.06 g/kg prednisone by gavage, for 7 days. Rats in the normal group were given the same volume of distilled water. The volume of administration was 15 mL/kg. MAIN OUTCOME MEASURES： Rat serum interleukin-10, tumor necrosis factor- α （TNF-α ）, nitric oxide, nitric oxide synthase levels, malondialdehyde content, superoxide dismutase activity and whole blood viscosity were measured in each group. Spinal cord around the site of the model was collected. Half the     

Anesthetic considerations for patients with acute cervical spinal cord injury

Anesthesiologists work to prevent or minimize secondary injury of the nervous system and improve the outcome of medical procedures.To this end,anesthesiologists must have a thorough understanding of pathophysiology and optimize their skills and equipment to make an anesthesia plan.Anesthesiologists should conduct careful physical examinations of patients and consider neuroprotection at preoperative interviews,consider cervical spinal cord movement and compression during airway management,and suggest awake fiberoptic bronchoscope intubation for stable patients and direct laryngoscopy with manual in-line immobilization in emergency situations.During induction,anesthesiologists should avoid hypotension and depolarizing muscle relaxants.Mean artery pressure should be maintained within 85–90 mmHg(1 mmHg = 0.133 kPa; vasoactive drug selection and fluid management).Normal arterial carbon dioxide pressure and normal blood glucose levels should be maintained.Intraoperative neurophysiological monitoring is a useful option.Anesthesiologists should be attentive to postoperative respiratory insufficiency(carefully considering postoperative extubation),thrombus,and infection.In conclusion,anesthesiologists should carefully plan the treatment of patients with acute cervical spinal cord injuries to protect the nervous system and improve patient outcome.     

Effects of durotomy versus myelotomy in the repair of spinal cord injury

Current management for spinal cord injury aims to reduce secondary damage and recover sensation and movement.Acute spinal cord injury is often accompanied by spinal cord compartment syndrome.Decompression by durotomy and/or myelotomy attempts to relieve secondary damage by completelyrelieving the compression of the spinal cord,removing the necrotic tissue,decreasing edema,reducing hemorrhage,and improving blood circulation in the spinal cord.However,it is controversial whether durotomy and/or myelotomy after spinal cord injury are beneficial to neurological recovery.This review compares the clinical effects of durotomy with those of myelotomy in the treatment of spinal cord injury.We found that durotomy has been performed more than myelotomy in the clinic,and that durotomy may be safer and more effective than myelotomy.Durotomy performed in humans had positive effects on neurological function in 92.3% of studies in this review,while durotomy in animals had positive effects on neurological function in 83.3% of studies.Myelotomy procedures were effective in 80% of animal studies,but only one clinical study of myelotomy has reported positive results,of motor and sensory improvement,in humans.However,a number of new animal studies have reported that durotomy and myelotomy are ineffective for spinal cord injury.More clinical data,in the form of a randomized controlled study,are needed to understand the effectiveness of durotomy and myelotomy.     

The glial scar in spinal cord injury and repair

Glial scarring following severe tissue damage and inflammation after spinal cord injury (SCI) is due to an extreme, uncontrolled form of reactive astrogliosis that typically occurs around the injury site. The scarring process includes the misalignment of activated astrocytes and the deposition of inhibitory chondroitin sulfate proteoglycans. Here, we first discuss recent developments in the molecular and cellular features of glial scar formation, with special focus on the potential cellular origin of scar-forming cells and the molecular mechanisms underlying glial scar formation after SCI. Second, we discuss the role of glial scar formation in the regulation of axonal regeneration and the cascades of neuro-inflammation. Last, we summarize the physical and pharmacological approaches targeting the modulation of glial scarring to better understand the role of glial scar formation in the repair of SCI.     

脊髓损伤大鼠损伤早期电位变化与损伤程度的关系

To investigate characteristics of injury potentials after different degrees of spinal cord injury in rats,the present study established models of spinal cord contusion with severe,moderate,and mild degrees of injury.Injury potential was measured in vivo using a direct current voltage amplification system.Results revealed that in the first 4 hours after acute spinal cord injury,initial amplitude of injury potential was greatest after severe injury,followed by moderate and mild injuries.Amplitude of injury potential decreased gradually with injury time,and the recession curve was logarithmic.Under the same degree of injuries,amplitude of rostral injury potential was generally less than caudal injury potential.Results suggested that injury potential reflected injury severity,because large initial amplitude of injury potential during the early injury stage implied severe injury.     

Sensory perception in complete spinal cord injury

OBJECTIVES: To describe sensations evoked by painful or repetitive stimulation below injury level in patients with a clinically complete (American Spinal Injury Association, ASIA Grade A) spinal cord injury (SCI). MATERIAL AND METHODS: Twenty-four patients (11 with central neuropathic pain and 13 without pain) with a traumatic SCI above the tenth thoracic vertebra were examined using quantitative sensory testing, MR imaging, and somatosensory evoked potentials (SEP). RESULTS: Painful (pressure, pinch, heat or cold) or repetitive (pinprick) stimuli elicited vague localized sensations in 12 patients (50%). Pain, spasticity, and spasms were equally seen in SCI patients with or without localized sensations. SEP and MRI did not differentiate between these two groups. CONCLUSION: The present study suggests retained sensory communication across the injury in complete SCI, i.e. 'sensory discomplete' SCI.     

Methylprednisolone inhibits Nogo-A protein expression after acute spinal cord injury

Oligodendrocyte-produced Nogo-A has been shown to inhibit axonal regeneration. Methylprednisolone plays an effective role in treating spinal cord injury, but the effect of methylprednisolone on Nogo-A in the injured spinal cord remains unknown. The present study established a rat model of acute spinal cord injury by the weight-drop method. Results showed that after injury, the motor behavior ability of rats was reduced and necrotic injury appeared in spinal cord tissues, which was accompanied by increased Nogo-A expression in these tissues. After intravenous injection of high-dose methylprednisolone, although the pathology of spinal cord tissue remained unchanged, Nogo-A expression was reduced, but the level was still higher than normal. These findings implicate that methylprednisolone could inhibit Nogo-A expression, which could be a mechanism by which early high dose methylprednisolone infusion helps preserve spinal cord function after spinal cord injury.     

Transplanting neural progenitors into a complete transection model of spinal cord injury

Neural progenitor cell (NPC) transplantation is a promising therapeutic strategy for spinal cord injury (SCI) because of the potential for cell replacement and restoration of connectivity. Our previous studies have shown that transplants of NPC, composed of neuron‐ and glia‐restricted progenitors derived from the embryonic spinal cord, survived well in partial lesion models and generated graft‐derived neurons, which could be used to form a functional relay. We have now examined the properties of a similar NPC transplant using a complete transection model in juvenile and adult rats. We found poor survival of grafted cells despite using a variety of lesion methods, matrices, and delays of transplantation. If, instead of cultured progenitor cells, the transplants were composed of segmental or dissociated segments of fetal spinal cord (FSC) derived from similar‐staged embryos, grafted cells survived and integrated well with host tissue in juvenile and adult rats. FSC transplants differentiated into neurons and glial cells, including astrocytes and oligodendrocytes. Graft‐derived neurons expressed glutaminergic and GABAergic markers. Grafted cells also migrated and extended processes into host tissue. Analysis of axon growth from the host spinal cord showed serotonin‐positive fibers and biotinylated dextran amine‐traced propriospinal axons growing into the transplants. These results suggest that in treating severe SCI, such as complete transection, NPC grafting faces major challenges related to cell survival and formation of a functional relay. Lessons learned from the efficacy of FSC transplants could be used to develop a therapeutic strategy based on neural progenitor cells for severe SCI. © 2014 Wiley Periodicals, Inc.     

Hydrogels in spinal cord injury repair strategies

Nowadays there are at present no efficient therapies for spinal cord injury (SCI), and new approaches have to be proposed. Recently, a new regenerative medicine strategy has been suggested using smart biomaterials able to carry and deliver cells and/or drugs in the damaged spinal cord. Among the wide field of emerging materials, research has been focused on hydrogels, three-dimensional polymeric networks able to swell and absorb a large amount of water. The present paper intends to give an overview of a wide range of natural, synthetic, and composite hydrogels with particular efforts for the ones studied in the last five years. Here, different hydrogel applications are underlined, together with their different nature, in order to have a clearer view of what is happening in one of the most sparkling fields of regenerative medicine.