Effects of Co-grafts Mesenchymal Stem Cells and Nerve Growth Factor Suspension in the Repair of Spinal Cord Injury

To investigate effect of the transplantation of mesenchymal stem cells （MSCs） in combination with nerve growth factor （NGF） on the repair of spinal cord injury （SCI） in adult rats, spinal cord of adult rats （n= 32） was injured by using the modified Allen＇ s method. One week after the injury, the injured cords were injected with Dubeeeo-modified Eagles medium （DMEM , Group Ⅰ ）, MSCs （Group Ⅱ ）, NGF （Group Ⅲ）, and MSCs plus NGF （Group Ⅳ）. One month and two months after the injury, rats were sacrificed and their injured cord tissues were sectioned for the identification of the transplanted cells. The axonal regeneration and the differentiation of MSCs were examined by immunoeytoehemieal staining. At the same time, rats were subjected to behavioral tests by using the open-field BBB scoring system. Immunoeytoehemieal staining showed that axonal regeneration and the transplanted cells partially expressed neuron-specific nuclear protein （NeuN） and glial fibrillary acidic protein （GFAP）. At the same time, significant improvement in BBB locomotor rating scale （P〈0. 05） were observed in the treatment group. More importantly, further functional improvement were noted in the combined treatment group. MSCs could differentiate into neurons and astroeytes. MSCs and NGF can promote axonal regeneration and improve functional recovery. There might exist a synergistic effect between MSCs and NGF.

The role of undifferentiated adipose-derived stem cells in peripheral nerve repair

Peripheral nerve injuries impose significant health and economic consequences, yet no surgical repair can deliver a complete recovery of sensory or motor function. Traditional methods of repair are less than ideal： direct coaptation can only be performed when tension-free repair is possible, and transplantation of nerve autograft can cause donor-site morbidity and neuroma formation. Cell-based therapy delivered via nerve conduits has thus been explored as an alternative method of nerve repair in recent years. Stem cells are promising sources of the regenerative core material in a nerve conduit because stem cells are multipotent in function, abundant in supply, and more accessible than the myelinating Schwann cells. Among different types of stem cells, undifferentiated adipose-derived stem cell（uASC）, which can be processed from adipose tissue in less than two hours, is a promising yet underexplored cell type. Studies of uASC have emerged in the past decade and have shown that autologous uASCs are non-immunogenic, easy to access, abundant in supply, and efficacious at promoting nerve regeneration. Two theories have been proposed as the primary regenerative mechanisms of uASC： in situ trans-differentiation towards Schwann cells, and secretion of trophic and anti-inflammatory factors. Future studies need to fully elucidate the mechanisms, side effects, and efficacy of uASC-based nerve regeneration so that uASCs can be utilized in clinical settings.

Adipose-derived stem cells modified by BDNF gene rescue erectile dysfunction after cavernous nerve injury

Cavernous nerve injury is the main cause of erectile dysfunction following radical prostatectomy.The recovery of erectile function following radical prostatectomy remains challenging.Our previous studies found that injecting adipose-derived stem cells(ADSCs)into the cavernosa could repair the damaged cavernous nerves,but the erectile function of the treated rats could not be restored to a normal level.We evaluated the efficacy of ADSCs infected with a lentiviral vector encoding rat brain-derived neurotrophic factor(lenti-rBDNF)in a rat model of cavernous nerve injury.The rats were equally and randomly divided into four groups.In the control group,bilateral cavernous nerves were isolated but not injured.In the bilateral cavernous nerve injury group,bilateral cavernous nerves were isolated and injured with a hemostat clamp for 2 minutes.In the ADSCGFP and ADSCrBDNF groups,after injury with a hemostat clamp for 2 minutes,rats were injected with ADSCs infected with lenti-GFP(1×106 in 20μL)and lenti-rBDNF(1×106 in 20μL),respectively.Erectile function was assessed 4 weeks after injury by measuring intracavernosal pressures.Then,penile tissues were collected for histological detection and western blot assay.Results demonstrated that compared with the bilateral cavernous nerve injury group,erectile function was significantly recovered in the ADSCGFP and ADSCrBDNF groups,and to a greater degree in the ADSCrBDNF group.Neuronal nitric oxide synthase content in the dorsal nerves and the ratio of smooth muscle/collagen were significantly higher in the ADSCrBDNF and ADSCGFP groups than in the bilateral cavernous nerve injury group.Neuronal nitric oxide synthase expression was obviously higher in the ADSCrBDNF group than in the ADSCGFP group.These findings confirm that intracavernous injection with ADSCs infected with lenti-rBDNF can effectively improve erectile dysfunction caused by cavernous nerve injury.This study was approved by the Medical Animal Care and Welfare Committee of Wuhan University,China(approval No.2017-1638)on June 20,2017.

Cognitive improvement following transvenous adipose-derived mesenchymal stem cell transplantation in a rat model of traumatic brain injury

The effects of adipose-derived mesenchymal stem cell (ADMSC) transplantation for the repair of traumatic brain injury remain poorly understood. The present study observed neurological functional changes in a rat model of traumatic brain injury following ADMSC transplantation via the tail vein. Cell transplants were observed in injured cerebral cortex, and expression of brain-derived nerve growth factor was significantly increased in the injured hippocampus following transplantation. Results demonstrated that transvenous ADMSC transplants migrated to the injured cerebral cortex and significantly improved cognitive function.

Artificial nerve graft constructed by coculture of activated Schwann cells and human hair keratin for repair of peripheral nerve defects

Studies have shown that human hair keratin(HHK) has no antigenicity and excellent mechanical properties. Schwann cells, as unique glial cells in the peripheral nervous system, can be induced by interleukin-1β to secrete nerve growth factor, which promotes neural regeneration. Therefore, HHK with Schwann cells may be a more effective approach to repair nerve defects than HHK without Schwann cells. In this study, we established an artificial nerve graft by loading an HHK skeleton with activated Schwann cells. We found that the longitudinal HHK microfilament structure provided adhesion medium, space and direction for Schwann cells, and promoted Schwann cell growth and nerve fiber regeneration. In addition, interleukin-1β not only activates Schwann cells, but also strengthens their activity and increases the expression of nerve growth factors. Activated Schwann cells activate macrophages, and activated macrophages secrete interleukin-1β, which maintains the activity of Schwann cells. Thus, a beneficial cycle forms and promotes nerve repair. Furthermore, our studies have found that the newly constructed artificial nerve graft promotes the improvements in nerve conduction function and motor function in rats with sciatic nerve injury, and increases the expression of nerve injury repair factors fibroblast growth factor 2 and human transforming growth factor B receptor 2. These findings suggest that this artificial nerve graft effectively repairs peripheral nerve injury.

Tissue engineering for the repair of peripheral nerve injury

Peripheral nerve injury is a common clinical problem and affects the quality of life of patients. Traditional restoration methods are not satisfactory. Researchers increasingly focus on the field of tissue engineering. The three key points in establishing a tissue engineering material are the biological scaffold material, the seed cells and various growth factors. Understanding the type of nerve injury, the construction of scaffold and the process of repair are necessary to solve peripheral nerve injury and promote its regeneration. This review describes the categories of peripheral nerve injury, fundamental research of peripheral nervous tissue engineering and clinical research on peripheral nerve scaffold material, and paves a way for related research and the use of conduits in clinical practice.

Transplantation of human umbilical cord blood mesenchymal stem cells to treat a rat model of traumatic brain injury

In the present study, human umbilical cord blood mesenchymal stem cells were injected into a rat model of traumatic brain injury via the tail vein. Results showed that 5-bromodeoxyuridine-labeled cells aggregated around the injury site, surviving up to 4 weeks post-transplantation. In addition, transplantation-related death did not occur, and neurological functions significantly improved. Histological detection revealed attenuated pathological injury in rat brain tissues following human umbilical cord blood mesenchymal stem cell transplantation. In addition, the number of apoptotic cells decreased. Immunohistochemistry and in situ hybridization showed increased expression of brain-derived neurotrophic factor, nerve growth factor, basic fibroblast growth factor, and vascular endothelial growth factor, along with increased microvessel density in surrounding areas of brain injury. Results demonstrated migration of transplanted human umbilical cord blood mesenchymal stem cells into the lesioned boundary zone of rats, as well as increased angiogenesis and expression of related neurotrophic factors in the lesioned boundary zone.

Functional recovery and microenvironmental alterations in a rat model of spinal cord injury following human umbilical cord blood-derived mesenchymal stem cells transplantation

BACKGROUND： Transplantation of human umbilical cord blood-derived mesenchymal stem cells （MSCs） has been shown to benefit spinal cord injury （SCI） repair. However, mechanisms of microenvironmental regulation during differentiation of transplanted MSCs remain poorly understood. OBJECTIVE： To observe changes in nerve growth factor （NGF）, brain-derived neurotrophic factor （BDNF）, and interleukin-8 （IL-8） expression following transplantation of human umbilical cord-derived MSCs, and to explore the association between microenvironment and neural functional recovery following MSCs transplantation. DESIGN, TIME AND SETTING： A randomized, controlled, animal experiment was performed at the Department of Orthopedics, First Affiliated Hospital of Soochow University from April 2005 to March 2007. MATERIALS： Human cord blood samples were provided by the Department of Gynecology and Obstetrics, First Affiliated Hospital of Soochow University. Written informed consent was obtained. METHODS： A total of 62 Wister rats were randomly assigned to control （n = 18）, model （n = 22, SCI ＋ PBS）, and transplantation （n = 22, SCI ＋ MSCs） groups. The rat SCI model was established using the weight compression method. MSCs were isolated from human umbilical cord blood and cultured in vitro for several passages. 5-bromodeoxyuridine （BrdU）-Iabeled MSCs （24 hours before injection） were intravascularly transplanted. MAIN OUTCOME MEASURES： The rats were evaluated using the Basso, Beattie and Bresnahan （BBB） locomotor score and inclined plane tests. Transplanted cells were analyzed following immunohistochemistry. Enzyme-linked immunosorbant assay was performed to determine NGF, BDNF, and IL-8 levels prior to and after cell transplantation. RESULTS： A large number of BrdU-positive MSCs were observed in the SCI region of the transplantation group, and MSCs were evenly distributed in injured spinal cord tissue 1 week after transplantation. BBB score and inclined plane test results revealed significant functional improvement in the transplantation group compared to the model group （P 〈 0.05）, which was maintained for 2-3 weeks. Compared to the model group, NGF and BDNF levels were significantly increased in the injured region following MSCs transplantation at 3 weeks （P 〈 0.05）, but IL-8 levels remained unchanged （P 〉 0.05）. CONCLUSION： MSCs transplantation increased NGF and BDNF expression in injured spinal cord tissue. MSCs could promote neurological function recovery in SCI rats by upregulating NGF expression and improving regional microenvironments.

Intraspinal transplantation of motoneuron-like cell combined with delivery of polymer-based glial cell line-derived neurotrophic factor for repair of spinal cord contusion injury

To evaluate the effects of glial cell line-derived neurotrophic factor transplantation combined with adipose-derived stem cells-transdifferentiated motoneuron delivery on spinal cord con-tusion injury, we developed rat models of spinal cord contusion injury, 7 days later, injected adipose-derived stem cells-transdifferentiated motoneurons into the epicenter, rostral and caudal regions of the impact site and simultaneously transplanted glial cell line-derived neuro-trophic factor-gelfoam complex into the myelin sheath. Motoneuron-like cell transplantation combined with glial cell line-derived neurotrophic factor delivery reduced cavity formations and increased cell density in the transplantation site. The combined therapy exhibited superior promoting effects on recovery of motor function to transplantation of glial cell line-derived neurotrophic factor, adipose-derived stem cells or motoneurons alone. These ifndings suggest that motoneuron-like cell transplantation combined with glial cell line-derived neurotrophic factor delivery holds a great promise for repair of spinal cord injury.

An update–tissue engineered nerve grafts for the repair of peripheral nerve injuries

Peripheral nerve injuries（PNI） are caused by a range of etiologies and result in a broad spectrum of disability. While nerve autografts are the current gold standard for the reconstruction of extensive nerve damage, the limited supply of autologous nerve and complications associated with harvesting nerve from a second surgical site has driven groups from multiple disciplines, including biomedical engineering, neurosurgery, plastic surgery, and orthopedic surgery, to develop a suitable or superior alternative to autografting. Over the last couple of decades, various types of scaffolds, such as acellular nerve grafts（ANGs）, nerve guidance conduits, and non-nervous tissues, have been filled with Schwann cells, stem cells, and/or neurotrophic factors to develop tissue engineered nerve grafts（TENGs）. Although these have shown promising effects on peripheral nerve regeneration in experimental models, the autograft has remained the gold standard for large nerve gaps. This review provides a discussion of recent advances in the development of TENGs and their efficacy in experimental models. Specifically, TENGs have been enhanced via incorporation of genetically engineered cells, methods to improve stem cell survival and differentiation, optimized delivery of neurotrophic factors via drug delivery systems（DDS）, co-administration of platelet-rich plasma（PRP）, and pretreatment with chondroitinase ABC（Ch-ABC）. Other notable advancements include conduits that have been bioengineered to mimic native nerve structure via cell-derived extracellular matrix（ECM） deposition, and the development of transplantable living nervous tissue constructs from rat and human dorsal root ganglia（DRG） neurons. Grafts composed of non-nervous tissues, such as vein, artery, and muscle, will be briefly discussed.

Use of nerve conduits for peripheral nerve injury repair:A Web of Science-based literature analysis

OBJECTIVE： To identify global research trends in the use of nerve conduits for peripheral nerve injury repair. DATA RETRIEVAL： Numerous basic and clinical studies on nerve conduits for peripheral nerve injury repair were performed between 2002-2011. We performed a bibliometric analysis of the institutions, authors, and hot topics in the field, from the Web of Science, using the key words peripheral nerve and conduit or tube. SELECTION CRITERIA： Inclusion criteria： peer-reviewed published articles on nerve conduits for peripheral nerve injury repair, indexed in the Web of Science; original research articles, reviews, meeting abstracts, proceedings papers, book chapters, editorial material, and news items. Exclusion criteria： articles requiring manual searching or telephone access; documents not published in the public domain; and several corrected papers. MAIN OUTCOME MEASURES： （a） Annual publication output; （b） publication type; （c） publication by research field; （d） publication by journal; （e） publication by funding agency; （f） publication by author; （g） publication by country and institution; （h） publications by institution in China; （i） most-cited papers. RESULTS： A total of 793 publications on the use of nerve conduits for peripheral nerve injury repair were retrieved from the Web of Science between 2002-2011. The number of publications gradually increased over the 10-year study period. Articles constituted the main type of publication. The most prolific journals were Biomaterials, Microsurge and Joumal of Biomedical Materials Research PartA. The National Natural Science Foundation of China supported 27 papers, more than any other funding agency. Of the 793 publications, almost half came from American and Chinese authors and institutions. CONCLUSION： Nerve conduits have been studied extensively for peripheral nerve regeneration; however, many problems remain in this field, which are difficult for researchers to reach a consensus.

Application of bioactive hydrogels combined with dental pulp stem cells for the repair of large gap peripheral nerve injuries

Due to the limitations in autogenous nerve grafting or Schwann cell transplantation,large gap peripheral nerve injuries require a bridging strategy supported by nerve conduit.Cell based therapies provide a novel treatment for peripheral nerve injuries.In this study,we first experimented an optimal scaffold material synthesis protocol,from where we selected the 10%GFD formula(10%GelMA hydrogel,recombinant human basic fibroblast growth factor and dental pulp stem cells(DPSCs))to fill a cellulose/soy protein isolate composite membrane(CSM)tube to construct a third generation of nerve regeneration conduit,CSM-GFD.Then this CSM-GFD conduit was applied to repair a 15-mm long defect of sciatic nerve in a rat model.After 12 week post implant surgery,at histologic level,we found CSM-GFD conduit could regenerate nerve tissue like neuron and Schwann like nerve cells and myelinated nerve fibers.At physical level,CSM-GFD achieved functional recovery assessed by a sciatic functional index study.In both levels,CSM-GFD performed like what gold standard,the nerve autograft,could do.Further,we unveiled that almost all newly formed nerve tissue at defect site was originated from the direct differentiation of exogeneous DPSCs in CSM-GFD.In conclusion,we claimed that this third-generation nerve regeneration conduit,CSM-GFD,could be a promising tissue engineering approach to replace the conventional nerve autograft to treat the large gap defect in peripheral nerve injuries.

脐血干细胞移植及电针治疗脊髓损伤大鼠神经生长因子及神经营养因子3的表达

背景:研究表明,脐血干细胞移植对脊髓损伤的恢复起促进作用,而电针也能够通过抑制星形胶质细胞增生,来减少损伤部瘢痕形成,故推测两者结合可能在急性脊髓损伤治疗中发挥重要作用。目的:观察人脐血干细胞局部移植联合督脉电针治疗后大鼠脊髓损伤组织神经生长因子、神经营养因子3的表达。方法:选取雌性SD大鼠72只,随机分为对照组、损伤组、移植组、联合组。对照组单纯性背部切口后缝合,损伤组脊髓横断处(T10水平)放置约1 mm×2 mm×2 mm大小、浸润生理盐水的明胶海绵;移植组及联合组在脊髓横断处放置浸润人脐血干细胞悬液的明胶海绵,联合组于造模后1 h开始给予督脉电针治疗。在相应处理7,14,28 d后应用免疫组织化学、Western Blot及实时荧光定量PCR方法检测脊髓组织神经生长因子、神经营养因子3表达量的变化。结果与结论:脊髓损伤后,移植组与损伤组相比,联合组与移植组相比,神经生长因子、神经营养因子3在7,14,28 d表达量均增加(P<0.05)。Western Blot、实时荧光定量PCR与免疫组化结果相一致。结果显示人脐血干细胞移植与电针联合治疗脊髓损伤具有协同作用,显著上调损伤脊髓神经生长因子、神经营养因子3的表达水平,有利于脊髓损伤后功能恢复。

同种异体骨髓间充质干细胞移植治疗大鼠脊髓损伤的时效性分析

目的:观察脊髓损伤后不同时间点骨髓间充质干细胞(bone mesenchymal stem cells,BMSCs)移植治疗后大鼠行为学变化、脊髓的病理改变及脑源性神经营养因子(brain-derived neurotrophic factor,BDNF)和神经生长因子(nerve growth factor,NGF)表达变化,探讨BMSCs的最佳移植时间。方法:80只健康成年SD大鼠随机分为8组,每组10只。A组为假损伤组,暴露胸10段脊髓但不造成冲击伤,B、C、D、E、F、G、H组以改良Allen法建立脊髓损伤模型。造模成功后,C、D、E、F、G、H组分别于损伤后0 h、6 h、24 h、3 d、5 d和7 d,将1×106体外培养的BMSCs用微量注射器注入于脊髓损伤局部,B组为单纯造模组,用等量细胞培养液代替。各组分别于损伤后1、2、4周进行脊髓运动功能BBB(Basso,Beattie,Bresnahan)运动学评分;分别取各组脊髓损伤组织0.5 cm,制作HE染色病理切片,观察其形态学改变;Elisa法检测各组大鼠脊髓BDNF和NGF表达情况。结果:假手术组1、2、4周大鼠脊髓功能BBB评分均明显高于其余7组(P<0.01);术后1周细胞移植各组评分与单纯造模组相比差异无统计学意义(P>0.05);术后2周和4周细胞移植各组评分高于单纯造模组(P<0.05);损伤后2周BBB评分从高到低依次为F、E、G、D、H、C组,但6组组间比较差异无统计学意义(P>0.05);损伤后4周BBB评分,F组与其余5组(C,D,E,G,H组)比较差异有统计学意义(P<0.05),但其余5组组间差异无统计学意义(P>0.05)。ELISA检测结果显示,F组BDNF和NGF含量均高于其他7组(P<0.05)。大鼠脊髓标本切片HE染色,假手术组脊髓组织结构完整清楚,无中性粒细胞浸润;其余7组局部组织水肿明显,灰白质交界处模糊,周围可见不同程度胶质细胞增生及炎细胞浸润。结论:大鼠脊髓损伤后同种异体BMSCs移植对脊髓功能恢复有一定疗效,损伤后3 d可能是BMSCs最佳移植时间。

肩袖损伤生物学修复的研究进展

肩袖损伤是一种临床常见的肩关节疾病,可导致患者肩关节疼痛、活动受限、生活质量下降。目前的治疗方法存在一定的局限性,常导致修复失败或肩袖再次撕裂,因此需要寻求一种新的、更加理想的修复方法。生物学修复的出现为肩袖损伤提供了一种新的治疗方法,有望恢复肩袖的正常组织结构。生物学修复包括应用生长因子和/或细胞促进肩袖肌腱再生,本文就生物学修复在肩袖损伤方面的研究进展作一综述。

骨髓间质干细胞经静脉注射移植对大鼠脊髓损伤后BDNF、NGFmRNA表达的影响

目的:研究大鼠骨髓间质干细胞(rat mesenchymal stemcells,rMSCs)静脉注射移植对脊髓损伤(spinal cordinjury,SCI)后脑源性神经营养因子(brain derived neurotrophic factor,BDNF)、神经生长因子(nerve growth factor,NGF)表达的影响,并探讨骨髓间质干细胞移植治疗大鼠脊髓损伤的机制。方法:运用改良Allen法制备大鼠T10脊髓外伤性截瘫模型,假手术组6只,损伤组84只随机分为对照组和rMSCs移植组。rMSCs组、假手术组接受rMSCs单细胞悬液1ml(1×106个rMSCs)自大鼠尾静脉缓慢注射移植,对照组静脉注射PBS1ml。移植后3h、6h、12h、24h、3d、7d、14d,应用RT-PCR方法检测损伤大鼠脊髓BDNF、NGFmRNA表达变化情况。结果:对照组和rMSCs移植组损伤脊髓BDNF、NGFmRNA表达较假手术组有明显增加(P<0.05);rMSCs移植组与对照组比较BDNF、NGFmRNA表达增加更为明显(P<0.05)。结论:脊髓损伤后损伤脊髓局部的BDNF、NGF表达增加,rMSCs静脉注射移植后能促进损伤脊髓局部的BDNF、NGF更进一步的表达,这可能是促进大鼠神经结构及神经功能恢复的因素之一。

神经生长因子修饰脂肪干细胞移植促进损伤脊髓的修复

背景:基因修饰的干细胞能够增加多肽和全长蛋白的分泌而起到保护脊髓损伤和促进神经元功能恢复的作用,因而成为近年来的研究热点。目的:探讨神经生长因子修饰的脂肪干细胞移植对大鼠脊髓损伤的保护作用。方法:贴壁培养法原代培养脂肪干细胞,免疫荧光法行表面标志物鉴定;脂质体介导神经生长因子质粒转染修饰脂肪干细胞,Real-time PCR及Western blot检测转染后神经生长因子的表达;改良Allen法构建大鼠脊髓损伤模型,将转染后的脂肪干细胞注射移植入大鼠脊髓损伤部位,BBB评分评估修复效果;脂肪干细胞移植后3周处死大鼠,Real-time PCR及Western blot检测移植后损伤节段脊髓中神经生长因子的表达。结果与结论:原代培养脂肪干细胞获得成功,免疫荧光显示表面抗原CD29和CD44呈阳性表达;转染后脂肪干细胞中神经生长因子mR NA及蛋白表达增高;转染神经生长因子的脂肪干细胞移植后,大鼠BBB评分明显升高,损伤节段脊髓中神经生长因子mR NA及蛋白表达明显升高。结果表明经神经生长因子转染修饰的脂肪干细胞可促进大鼠脊髓损伤修复。

KLF7联合脂肪源性干细胞对脊髓损伤大鼠运动功能的影响及其机制

目的观察KLF样转录因子7(KLF7)联合脂肪源性干细胞(ADSC)对脊髓损伤大鼠运动功能的影响,并探讨其可能的机制。方法将30只SD大鼠随机分为KLF7联合ADSC组、ADSC组及对照组,每组10只,均采用离断右半脊髓的方法制备脊髓损伤模型。KLF7联合ADSC组于脊髓损伤组织注入100μL ADSC(ADSC均采用PKH26进行标记)及2μL AAV2-KLF7腺病毒,ADSC组仅注入100μL ADSC,对照组仅注入100μL PBS。术后1天及1、2、3、4周行运动功能评分(BBB评分);术后4周,应用诱发电位仪和磁刺激器经颅磁刺激运动诱发神经电生理反应,记录神经传导速度、潜伏期及波幅。术后4周处死,采用Western boltting法检测脊髓损伤组织KLF7、神经生长因子(NGF)及其受体酪氨酸激酶A(TrkA)蛋白相对表达量,计算脊髓损伤面积百分比及ADSC数量(以PKH26的光密度值表示)。结果与术后1天比较,各组术后1、2、3、4周BBB评分均升高(P均<0.05)。术后4周,KLF7联合ADSC组与ADSC组BBB评分、神经传导速度、波幅、ADSC数量及脊髓损伤组织NGF、TrkA蛋白相对表达量均高于对照组,潜伏期及脊髓损伤面积百分比均低于对照组,且KLF7联合ADSC组上述变化更明显(P均<0.05)。KLF7联合ADSC组脊髓损伤组织KLF7蛋白相对表达量均高于ADSC组及对照组(P均<0.05)。结论KLF7联合ADSC可减轻脊髓损伤大鼠的神经损伤,改善其运动功能;其机制可能与KLF7促进ADSC存活及提高脊髓损伤组织NGF、TrkA表达有关。

脑创伤后NGF对神经干细胞Nestin蛋白表达的影响

目的 研究脑创伤后外源性神经生长因子 (NGF)对神经干细胞Nestin蛋白表达的影响及其意义。方法 建立大鼠流体脑创伤模型 ,采用免疫细胞化学及图像分析等方法 ,观察脑创伤后非NGF处理组和NGF处理组Nestin蛋白表达的变化。结果 成年大鼠Nestin阳性细胞主要位于室管膜下组织 ,细胞的形态主要是胶质细胞。脑创伤后Nestin阳性细胞在室管膜下反应性增加 ,以伤后 7d明显 ,同时在创伤区域周围也可见到大量的Nestin阳性细胞 ,并在伤后 14d继续维持其反应性增加。NGF处理组伤后 7dNestin阳性细胞在伤灶周围更加明显 ,为 2 8.7± 3.8,比同时相点的非NGF处理组明显增加 (P <0 .0 1)。结论 外源性NGF能明显促进脑创伤后Nestin阳性细胞数量的增加 ,增强星形胶质细胞对脑创伤的反应并使其表现有神经干细胞的特征 ,参与神经细胞的再生和重塑。

外源性神经生长因子和碱性成纤维细胞生长因子联合应用促进重型脑创伤模型大鼠内源性脑细胞的增殖

背景:研究证明神经生长因子、碱性成纤维细胞生长因子能够明显在体外促进神经干细胞的自我更新及分化,二者联合应用对成年大鼠脑创伤后内源性脑细胞的影响研究甚少。目的:探索外源性神经生长因子和碱性成纤维细胞生长因子对重型脑创伤大鼠内源性大脑组织细胞的影响。方法:以改良Feeney氏法对48只SD大鼠进行脑创伤造模,造模后随机将48只大鼠分为神经生长因子组、碱性成纤维细胞生长因子组、联合组、对照组。造模后24 h,各组分别在脑室内注入对应的神经营养因子,对照组注射生理盐水。采用行为学实验观察肢体恢复情况,免疫组化法比较各组大鼠脑内BrdU阳性细胞的表达。结果与结论:①从造模第5天开始神经生长因子组、碱性成纤维细胞生长因子组、联合组行为学实验评分均小于对照组(P <0.05),且联合组评分低于神经生长因子组、碱性成纤维细胞生长因子组(P <0.05);②神经生长因子组、碱性成纤维细胞生长因子组、联合组BrdU阳性细胞数量明显多于对照组,差异有显著性意义(P <0.05),同时联合组BrdU阳性细胞明显多于神经生长因子组、碱性成纤维细胞生长因子组(P <0.05);③结果表明,外源性神经生长因子和碱性成纤维细胞生长因子可加快脑创伤大鼠肢体功能恢复和促进大脑组织细胞的增殖,且神经生长因子和碱性成纤维细胞生长因子的联合使用能取得更加显著的效果。