周围神经损伤后局部一次给予重组CNTF对神经元变性和再 …

目的：研究周围神经损伤后,局部一次给予重组ＣＮＴＦ对神经元变性和再生的作用。方法：用硅管套接切断的成年大鼠坐骨神经,术时在损伤神经局部一次性给予重组ＣＮＴＦ;用甲苯胺蓝染色和胆碱酯酶组织化学方法研究神经元的逆行变性;用ＨＲＰ逆行追踪研究轴突的再生,并进行后足功能测试。结果：重组ＣＮＴＦ减轻损伤运动神经元胞核偏位和胆碱酯酶活性的变化,增加轴突再生的运动神经元数量,改善功能指数。结论：局部一次给予重组     

周围神经再生时重组CNTF对受损神经元 STAT3表达和酪氨酸磷酸化的作用

目的 研究周围神经再生时,重组睫状神经营养因子(CNTF)对受损神经元JAK-STAT途径和酪氨酸磷酸化的作用。方法 用硅管套接切断的成年大鼠坐骨神经,术时在受损神经局部给予重组CNTF,用免疫组织化学ABC法结合计算机图像分析研究STAT3、磷酸化酪氨酸(PTyr)免疫反应阳性物质在L3～5段脊髓前角外侧核和L5脊神经节神经元中的分布和相对含量。结果 与生理盐水组相比,CNTF组脊髓前角外侧核神经元胞核STAT3和胞膜PTyr阳性物质的含量更高,脊神经节神经元胞浆和胞核,PTyr阳性物质的含量更高。结论 重组CNTF能激活和强化受损运动神经元的JAK-STAT途径,增强受损神经元的酪氨酸磷酸化。     

重组睫状神经营养因子对周围神经再生中多种细胞的作用

为了解重组睫状神经营养因子 ( CNTF)对周围神经再生中多种细胞的作用 ,用硅管套接切断的成年大鼠坐骨神经 ,在受损神经局部一次性给予重组睫状神经营养因子 :用免疫组织化学 ABC法结合计算机图像分析观测再生神经中 GAP-4 3、S10 0、CD68、MHC- 免疫反应阳性物质的变化。与生理盐水对照组相比 ,证明 CNTF组再生神经中上述四种物质显著增多。结果提示重组睫状神经营养因子能促进轴突的再生、Schwann细胞的迁入、单核细胞的渗出和活化     

CNTF对慢性高眼压大鼠RGCs的保护作用

目的 研究慢性高眼压大鼠玻璃体腔内注射睫状神经营养因子(ciliary neurotrophic factor,CNTF)对大鼠视网膜神经节细胞(retinal ganglion cells,RGCs)的保护作用.方法 大鼠随机分成1、2、3、4周组,制作慢性高眼压模型,实验眼玻璃体注入CNTF 0.5 μg,对照眼注入5 μl磷酸钠溶液,各实验点光镜观察和进行免疫组化检测,采用图像分析系统分析.结果 HE染色光镜观察分析,1、2、3周实验组RGCs数明显多于对照组(P<0.05),RGCs略有肿胀,形态趋于正常,4周实验组和对照组形态差异不明显;GAP-43免疫组织化学检测,2、3、4周实验组RGCs层阳性染色与对照组相比有显著性差异(P<0.05),1周实验组RGCs阳性染色较少(P>0.05).结论 CNTF对慢性高眼压动物RGCs起到一定的保护作用并可促进RGCs再生.     

睫状神经营养因子对视网膜色素变性rd小鼠感光细胞作用的电镜观察

目的观察玻璃体腔注射睫状神经营养因子(ciliary neurotrophic factor,CNTF)对视网膜色素变性小鼠模型(retinal degeneration,rd)视网膜感光细胞的作用。方法将12只出生10d(P10)rd小鼠随机分成3组:CNTF治疗组、PBS(磷酸缓冲液)注射组、空白对照组;CNTF治疗组和PBS注射组的玻璃体腔分别注射鼠CNTF和磷酸缓冲液PBS,在出生后14d过量麻醉处死小鼠,取眼球行光、电镜观察。结果透射电镜结果显示凋亡是rd小鼠视网膜色素变性的主要病理表现,同时有炎症的参与,CNTF治疗组的rd小鼠视网膜光感受器细胞的超微结构好于对照组。结论CNTF玻璃体腔注射对视网膜色素变性rd小鼠视网膜感光细胞凋亡有抑制作用。     

针刺对备用背根节神经元CNTF和PDGF表达的影响

目的探讨部分去背根后针刺对备用背根节神经元睫状神经营养因子(CNTF)及血小板源性生长因子(PDGF)表达的影响。方法制备猫双侧备用背根模型(切除双侧L1～L5、L7～S2背根节,保留L6背根节为备用背根节)。针刺位于右侧备用根支配区的两组穴位。针刺7d及14d后取备用背根节用CNTF抗血清(1∶500)及PDGF抗血清(1∶200)行免疫组织化学ABC法染色。分别记数各组阳性总、大及中小神经元的数量。结果正常组左右L6背根节的细胞数无差异,CNTF、PDGF阳性神经元数在7d、14d时与正常组比较无差异。针刺侧CNTF阳性总、大及中小神经元数在针刺7d时均显著多于非针刺侧(P<0.05),而针刺14d时,只有阳性大神经元数多于非针刺侧(P<0.05)。PDGF阳性总及大神经元数针刺7d时多于非针刺侧(P<0.05),针刺14d时,阳性总及中小神经元多于非针刺侧(P<0.05)。结论针刺可促进去背根后备用背根节CNTF、PDGF的表达,这种促进作用显效的时间因不同因子和不同种类的背根节神经元而异。     

重组睫状神经营养因子对受损周围神经施万细胞相关基因表达的作用

目的研究重组睫状神经营养因子(CNTF)对受损周围神经施万细胞基因表达的作用。方法用硅管套接切断的大鼠坐骨神经,在受损神经局部给予重组CNTF,术后用免疫组织化学ABC法结合计算机图像分析观测S100蛋白(S100)、生长相关蛋白-43(GAP-43)、磷酸化酪氨酸(PTyr)、信号转导子和转录激活子(STAT)3的免疫反应阳性物质在修复侧远段神经的分布和相对含量。结果CNTF组修复侧远段神经相应区域S100、GAP-43、PTyr、STAT3阳性物质的含量显著或非常显著高于生理盐水组。结论重组CNTF能上调受损神经施万细胞S100、GAP-43、PTyr和STAT3的表达,提示重组CNTF通过强化受损神经施万细胞JAK-STAT途径,E调其S100和GAP-43的基因表达。     

坐骨神经损伤后雏菊叶龙胆的修复作用实验研究

目的观察雏菊叶龙胆是否对坐骨神经损伤后有促进功能恢复的作用,其中是否有睫状神经营养因子的参与。方法雄性Wistar大鼠225只,右侧坐骨神经离断后显微镜下缝合。造模后随机分为对照组、雏菊叶龙胆25 mg组、50 mg组、75 mg组和甲钴胺组5组。对照组生理盐水注射,其他组相应剂量的雏菊叶龙胆及甲钴胺注射,1、3、5周测定神经传导速度及腓肠肌肌细胞截面积,免疫组化分析睫状神经营养因子(CNTF)阳性细胞比率。结果雏菊叶龙胆50 mg、75 mg组与对照组、甲钴胺组神经传导速度相比有明显差异,雏菊叶龙胆25 mg组与75 mg、50 mg组相比有明显差异(P=0.025)。3周时对照组、甲钴胺组、雏菊叶龙胆25 mg、50 mg、75 mg组腓肠肌肌细胞截面积分别为:(455.06±29.38)μm2、(679.03±81.48)μm2、(465.31±71.55)μm2、(670.24±91.26)μm2、(669.28±78.54)μm2,对照组、雏菊叶龙胆25 mg组与其他组比较有显著差异(P0.05)。3周时各组睫状神经营养因子免疫组化可见雏菊叶龙胆25 mg组和对照组与雏菊叶龙胆50 mg、75 mg组比较结果有统计学差异。结论雏菊叶龙胆可促进坐骨神经损伤后功能恢复,可促进神经功能恢复中有睫状神经营养因子参与。     

重组睫状神经营养因子对胶质瘤细胞形态和基因表达的影响

重组睫状神经营养因子对胶质瘤细胞形态和基因表达的影响张树辉詹洲陶霞田野苹何成作者单位：２２１００４解放军第九七医院病理科［张树辉（现在４０００３８第三军医大学病理学教研室）、陶霞］；第二军医大学病理学教研室（詹洲、田野苹、何成）研究表明，睫状神经...     

神经生长因子对周围神经损伤后再生和修复的实验研究

手术切除５ｍｍ兔的尺神经，在两断端间连接肌桥并套装硅胶管，形成一个封闭腔，向腔内注入神经生长因子。间隔不同时间取尺神经桥接区、桥接区近段、远段、尺神经的脊髓投射节段和相应脊神经节，用光镜和电镜观察神经溃变和再生情况并作图像分析；用酶标示踪和电生理方法检测神经通路的重建状况。结果显示，周围神经离断后，肌束桥接并用硅胶管套装后注入外源性神经生长因子，可明显地促进离断神经的再生和修复。     

The promotion of peripheral nerve regeneration by chitooligosaccharides in the rat nerve crush injury model

Chitooligosaccharides (COSs), the biodegradation product of chitosan, have shown many biological functions. In this study, we examined the possible benefits of treatment with COSs (M.W. 800) on regeneration of rat crushed sciatic nerves. The rats with sciatic nerve crush injury were administered intraperitoneally daily with 3 or 6 mg/kg body weight of COSs over a 3-week period. During and at the end of COSs treatment, a series of functional and histological examinations, including the measurement of withdrawal reflex latency (WRL) values, walking track analysis, electrophysiological assessments, morphometric analysis of gastrocnemius muscle, as well as immunohistochemistry and electromicroscopy to regenerated sciatic nerves, were performed to evaluate the therapeutic outcomes of COSs. The experimental data demonstrated that COSs promoted peripheral nerve regeneration with the desired functional recovery in the rat sciatic nerve crush injury model. This study raises a possibility of developing COSs as a potential neuroprotective agent for peripheral nerve repair applications.     

Development and evaluation of silk fibroin-based nerve grafts used for peripheral nerve regeneration

Silk fibroin (SF), derived from natural silk long used as a textile material, has recently become an important biomaterial for tissue engineering applications. We have previously reported on good in vitro biocompatibility of SF fibers with peripheral nerve tissues and cells. In the present study, we developed a novel biomimetic design of the SF-based nerve graft (SF graft) which was composed of a SF-nerve guidance conduit (NGC) inserted with oriented SF filaments. The SF-NGC prepared via well-established procedures exhibits an eggshell-like microstructure that is responsible for its superior mechanical and permeable properties beneficial to nerve regeneration. The SF graft was used for bridge implantation across a 10-mm long sciatic nerve defect in rats, and the outcome of peripheral nerve repair at 6 months post-implantation was evaluated by a combination of electrophysiological assessment, FluoroGold retrograde tracing and histological investigation. The examined functional and morphological parameters show that SF grafts could promote peripheral nerve regeneration with effects approaching those elicited by nerve autografts which are generally considered as the gold standard for treating large peripheral nerve defects, thus raising a potential possibility of using these newly developed nerve grafts as a promising alternative to nerve autografts.     

Recellularized nerve allografts with differentiated mesenchymal stem cells promote peripheral nerve regeneration

Chemical-extracted acellular nerve allografting, containing the natural nerve structure and elementary nerve extracellular matrix (ECM), has been used for peripheral nerve-defect treatment experimentally and clinically. However, functional outcome with acellular nerve allografting decreases with increased size of gap in nerve defects. Cell-based therapy is a good strategy for repairing long nerve defects. Bone-marrow-derived mesenchymal stem cells (BMSCs) and adipose-derived mesenchymal stem cells (ADSCs) can be induced to differentiate into cells with Schwann cell-like properties (BMSC-SCs or ADSC-SCs), which have myelin-forming ability in vitro and secrete trophic nerve growth factors. Here, we aimed to determine whether BMSC-SCs or ADSC-SCs are a promising cell type for enriching acellular grafts in nerve repair. We evaluated axonal regeneration distance by immunofluorescence staining after 2-week implantation. We used functional and histomorphometric analysis to evaluate 3-month regeneration of the novel cell-supplemented tissue-engineered nerve graft used to bridge a 15-mm-long sciatic nerve gap in rats. Introducing BMSC-SCs or ADSC-SCs to the acellular nerve graft promoted sciatic nerve regeneration and functional recovery. Nerve regeneration with BMSC-SCs or ADSC-SCs was comparable to that with autografting and Schwann cells alone and better than that with acellular nerve allografting alone. Differentiated bone-marrow-or adipose-derived MSCs may be a promising cell source for tissue-engineered nerve grafts and promote functional recovery after peripheral nerve injury.     

Conductive PPY/PDLLA conduit for peripheral nerve regeneration

The significant drawbacks and lack of success associated with current methods to treat critically sized nerve defects have led to increased interest in neural tissue engineering. Conducting polymers show great promise due to their electrical properties, and in the case of polypyrrole (PPY), its cell compatibility as well. Thus, the goal of this study is to synthesize a conducting composite nerve conduit with PPY and poly(d, l-lactic acid) (PDLLA), assess its ability to support the differentiation of rat pheochromocytoma 12 (PC12) cells in vitro, and determine its ability to promote nerve regeneration in vivo. Different amounts of PPY (5%, 10%, and 15%) are used to synthesize the conduits resulting in different conductivities (5.65, 10.40, and 15.56 ms/cm, respectively). When PC12 cells are seeded on these conduits and stimulated with 100 mV for 2 h, there is a marked increase in both the percentage of neurite-bearing cells and the median neurite length as the content of PPY increased. More importantly, when the PPY/PDLLA nerve conduit was used to repair a rat sciatic nerve defect it performed similarly to the gold standard autologous graft. These promising results illustrate the potential that this PPY/PDLLA conducting composite conduit has for neural tissue engineering.     

Substrate-mediated nanoparticle/gene delivery to MSC spheroids and their applications in peripheral nerve regeneration

Substrate-derived mesenchymal stem cell (MSC) spheroids show greater differentiation capacities than dispersed single cells in vitro. During spheroid formation, nanoparticles (NPs)/genes may be delivered into the cells. In this study, MSCs were conveniently labeled with superparamagnetic Fe₃O₄ NPs, or transfected with brain-derived neurotrophic factor (BDNF) gene, by the substrate-mediated NP/gene uptake. With the promising in vitro data showing the beneficial effect on neural development and neurotrophic factor expression, MSCs were combined with a polymeric nerve conduit to bridge a 10 mm transection gap of rat sciatic nerve. High-resolution (7-T) magnetic resonance imaging (MRI) was used to track the transplanted cells. Nerve regeneration was assessed by functional recovery and histology. Results revealed that Fe₃O₄ NP-labeled MSCs were successfully visualized by MRI in vivo. Animals receiving BDNF-transfected MSC spheroids demonstrated the shortest gap bridging time (<21 days), the largest regenerated nerve, and the thickest myelin sheath at 31 days. Compared to MSC single cells, the pristine or BDNF-transfected MSC spheroids significantly promoted the functional recovery of animals, especially for the BDNF-transfected MSC spheroids. The transplanted MSCs were incorporated in the regenerated nerve and differentiated into non-myelinating Schwann cells after 31 days. This study suggests that the substrate-mediated gene delivery and NP labeling may provide extra values for MSC spheroids to carry therapeutic/diagnostic agents in cell-based therapy.     

神经节苷脂M_1对兔子运动神经再生影响的实验研究

目的研究局部应用神经节苷脂M1(GM1)对兔子运动神经-面神经损伤的修复作用,为临床早期应用神经节甘脂M1,促进面神经损伤再生提供理论和实验依据。方法将18只健康成年新西兰大白兔按随机原则分为实验组(神经节苷脂M1组)和空白对照组。建立兔面神经损伤后再生的实验模型,实验组于面神经吻合处滴注2.0μL(10μg)GM1溶液,空白对照组于面神经吻合后未作任何处理,分别在术后2周、4周、8周观察面神经的传导速度及组织学变化。结果术后2周、4周神经传导速度,实验组分别为(5.35±0.74)m/s,(14.25±1.3)m/s,空白对照组分别为(3.32±0.30)m/s,(8.10±0.92)m/s,实验组与空白对照组比较,差异有统计学意义(P0.05),术后8周神经传导速度,实验组与空白对照组比较差异无统计学意义(P0.05),光学显微镜观察术后2周、4周实验组神经再生状况优于空白对照组,光学显微镜观察术后8周实验组与空白对照组神经再生状况差别不大。结论兔面神经横断伤后立即应用神经节苷脂M1对面神经损伤后早期(2周,4周)再生恢复有明显的促进作用。     

高频超声在周围神经损伤与再生诊断的应用进展

目的总结高频超声在周围神经损伤与再生诊断领域的应用价值。方法以“高频超声”、“周围神经损伤”和“神经再生”作为关键词,在Elsevier ScienceDirecr、EBSCO全文数据库、万方数据、中国知网等数据库中检索近年发表的相关文章,并对高频超声在周围神经损伤领域诊断进展情况进行归纳总结。结果高频超声诊断周围神经损伤临床上具有多元的方法;临床上神经多平面性损伤很难通过电生理以及其他方式进行诊断,但利用超声检查可诊断出多节段损伤,避免治疗的盲目性、减少手术次数并为手术提供了明确的手术入路。结论尽管对周围神经损伤的认识已相当成熟,但其早期诊断方法在临床上尚存在争议及进步空间。如何利用高频超声在术前有形态学证据诊断神经损伤成为高频超声之优势。     

低照度激光辐射周围神经组织损伤修复的研究进展

周围神经损伤修复是神经组织损伤康复研究领域中的一项重要课题.目前,周围神经损伤治疗的新技术很多,随着激光对生物作用机制研究的发展,低照度激光辐射周围神经组织损伤修复作为一种新的组织再生方法被应用到神经损伤修复领域.主要围绕弱激光照射神经组织修复机制以及周围神经损伤后功能恢复和神经组织部位瘢痕抑制进行论述,并对激光照射神经损伤治疗和修复的新进展作一综述.     

Survival and regeneration of cutaneous and muscular afferent neurons after peripheral nerve injury in adult rats

Peripheral nerve injury induces the retrograde degeneration of dorsal root ganglion (DRG) cells, which affects predominantly the small-diameter cutaneous afferent neurons. This study compares the time-course of retrograde cell death in cutaneous and muscular DRG cells after peripheral nerve transection as well as neuronal survival and axonal regeneration after primary repair or nerve grafting. For comparison, spinal motoneurons were also included in the study. Sural and medial gastrocnemius DRG neurons were retrogradely labeled with the fluorescent tracers Fast Blue (FB) or Fluoro-Gold (FG) from the homonymous transected nerves. Survival of labeled sural and gastrocnemius DRG cells was assessed at 3 days and 1–24 weeks after axotomy. To evaluate axonal regeneration, the sciatic nerve was transected proximally at 1 week after FB-labeling of the sural and medial gastrocnemius nerves and immediately reconstructed using primary repair or autologous nerve grafting. Twelve weeks later, the fluorescent tracer Fluoro-Ruby (FR) was applied 10 mm distal to the sciatic lesion in order to double-label sural and gastrocnemius neurons that had regenerated across the repair site. Counts of labeled gastrocnemius DRG neurons did not reveal any significant retrograde cell death after nerve transection. In contrast, sural axotomy induced a delayed loss of sural DRG cells, which amounted to 22% at 4 weeks and 43–48% at 8–24 weeks postoperatively. Proximal transection of the sciatic nerve at 1 week after injury to the sural or gastrocnemius nerves neither further increased retrograde DRG degeneration, nor did it affect survival of sural or gastrocnemius motoneurons. Primary repair or peripheral nerve grafting supported regeneration of 53–60% of the spinal motoneurons and 47–49% of the muscular DRG neurons at 13 weeks postoperatively. In the cutaneous DRG neurons, primary repair or peripheral nerve grafting increased survival by 19–30% and promoted regeneration of 46–66% of the cells. The present results suggest that cutaneous DRG neurons are more sensitive to peripheral nerve injury than muscular DRG cells, but that their regenerative capacity does not differ from that of the latter cells. However, the retrograde loss of cutaneous DRG cells taking place despite immediate nerve repair would still limit the recovery of cutaneous sensory functions.