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Peripheral Nerve Regeneration (peripheral + nerve_regeneration)
Selected AbstractsFabrication and Evaluation of Chitin-Based Nerve Guidance Conduits Used to Promote Peripheral Nerve Regeneration,ADVANCED ENGINEERING MATERIALS, Issue 11 2009Yumin Yang Chitin product was prepared from the chitosan counterpart and both were found to be equally biocompatible with cultured Schwann cells. Chitin- and chitosan-based nerve guidance conduits (NGCs) were surgically implanted to bridge 10-mm-long neural defects in rat sciatic nerves. The regenerative outcome provided positive evidence that chitin- and chitosan-based NGCs produce the similar beneficial effects on peripheral nerve regeneration. [source] Highly Permeable Genipin-Cross-linked Gelatin Conduits Enhance Peripheral Nerve RegenerationARTIFICIAL ORGANS, Issue 12 2009Ju-Ying Chang Abstract Here we have evaluated peripheral nerve regeneration with a porous biodegradable nerve conduit (PGGC), which was made from genipin-cross-linked gelatin. To examine the effect of pores, nonporous genipin-cross-linked gelatin conduit (GGC) was considered as the control. Both the PGGC and the GGC were dark blue in appearance with a concentric and round lumina. The PGGC featured an outer surface with pores of variable size homogeneously traversing, and a partially fenestrated inner surface connected by an open trabecular meshwork. The GGC had a rough outer surface whereas its inner lumen was smooth. Both PGGCs and GGCs had similar hydrophilicity on condition of the same material and cross-linking degree. The porosity of PGGCs and GGCs was 90.8 ± 0.9% and 24.3 ± 2.9%, respectively. The maximum tensile force of the GGCs (0.12 ± 0.06 kN) exceeded that of the PGGCs (0.03 ± 0.01 kN), but the PGGCs had a higher swelling ratio than GGCs at 0.5, 1, 3, 6, 12, 24, 48, 60, 72, and 84 h after soaking in deionized water. Cytotoxic testing revealed the soaking solutions of both of the tube composites would not produce cytotoxicity to cocultured Schwann cells. After subcutaneous implantation on the dorsal side of the rat, the PGGC was degraded completely after 12 weeks of implantation whereas a thin tissue capsule was formed encapsulating the partially degraded GGC. Biodegradability of both of the tube groups and their effectiveness as a guidance channel were examined as they were used to repair a 10 mm gap in the rat sciatic nerve. As a result, fragmentation of the GGC was still seen after 12 weeks of implantation, yet the PGGC had been completely degraded. Histological observation showed that numerous myelinated axons had crossed over the gap region in the PGGCs after 8 weeks of implantation despite only few myelinated axons and unmyelinated axons mostly surrounded by Schwann cells seen in the GGCs. In addition, the regenerated nerves in the PGGCs presented a significantly higher nerve conductive velocity than those in the GGCs (P < 0.05). Thus, the PGGCs can not only offer effective aids for regenerating nerves but also accelerate favorable nerve functional recovery compared with the GGCs. [source] A Novel Approach to Align Adult Neural Stem Cells on Micropatterned Conduits for Peripheral Nerve Regeneration: A Feasibility StudyARTIFICIAL ORGANS, Issue 1 2009Shan-hui Hsu Abstract There is a strong need for nerve-tissue engineering using the guide conduit and Schwann cells or neural stem cells (NSCs) with regeneration potential for injured peripheral nerves. In this study, micropatterned poly(d,l -lactide) (PLA) conduits were fabricated by microlithography and solvent-casting. The PLA conduits were seeded with the novel green fluorescent protein (GFP)-positive adult mouse NSCs obtained using the patented method of one of the authors. About 85% of the seeded NSCs were successfully aligned on the micropatterned conduits within 72 h and expressed the genes related to the production of neurotrophic factors. Gene expressions for the neurotrophic factors, such as nerve growth factor and brain-derived neurotrophic factor were upregulated by the micropatterned conduits at 72 h. The micropatterned PLA conduits seeded with the aligned NSCs were used to bridge the 10-mm sciatic nerve gaps in rats and were found to facilitate nerve repair and functional recovery during a period of 6 weeks compared with the nonseeded group. This model can be used to study the role of adult NSCs in peripheral-nerve regeneration in the future. [source] Immediate anti-tumor necrosis factor-, (etanercept) therapy enhances axonal regeneration after sciatic nerve crushJOURNAL OF NEUROSCIENCE RESEARCH, Issue 2 2010Kinshi Kato Abstract Peripheral nerve regeneration begins immediately after injury. Understanding the mechanisms by which early modulators of axonal degeneration regulate neurite outgrowth may affect the development of new strategies to promote nerve repair. Tumor necrosis factor-, (TNF-,) plays a crucial role in the initiation of degenerative cascades after peripheral nerve injury. Here we demonstrate using real-time Taqman quantitative RT-PCR that, during the time course (days 1,60) of sciatic nerve crush, TNF-, mRNA expression is induced at 1 day and returned to baseline at 5 days after injury in nerve and the corresponding dorsal root ganglia (DRG). Immediate therapy with the TNF-, antagonist etanercept (fusion protein of TNFRII and human IgG), administered systemically (i.p.) and locally (epineurially) after nerve crush injury, enhanced the rate of axonal regeneration, as determined by nerve pinch test and increased number of characteristic clusters of regenerating nerve fibers distal to nerve crush segments. These fibers were immunoreactive for growth associated protein-43 (GAP-43) and etanercept, detected by anti-human IgG immunofluorescence. Increased GAP-43 expression was found in the injured nerve and in the corresponding DRG and ventral spinal cord after systemic etanercept compared with vehicle treatments. This study established that immediate therapy with TNF-, antagonist supports axonal regeneration after peripheral nerve injury. © 2009 Wiley-Liss, Inc. [source] Peripheral nerve regeneration in cell adhesive peptide incorporated collagen tubes in rat sciatic nerve , early and better functional regainJOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 4 2005Mohamed Rafiuddin Ahmed [source] Impaired nerve regeneration in reeler mice after peripheral nerve injuryEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 1 2008Erika Lorenzetto Abstract Reelin, an extracellular matrix protein, plays an important role in the regulation of neuronal migration and cortical lamination in the developing brain. Little is known, however, about the role of this protein in axonal regeneration. We have previously shown that Reelin is secreted by Schwann cells in the peripheral nerve compartment during postnatal development and that it is up-regulated following nerve injury in adult mice. In this work, we generated mice deficient in Reelin (reeler) that express yellow fluorescent protein (YFP) in a subset of neurons and examined the axonal regeneration following nerve crush. We found that axonal regeneration was significantly altered compared with wild-type mice. By contrast, retrograde tracing with Fluorogold dye after sciatic nerve crush was unaffected in these mutants, being comparable with normal axonal transport observed in wild-type. These results indicate that the absence of Reelin impairs axonal regeneration following injury and support a role for this protein in the process of peripheral nerve regeneration. [source] Endogenous BDNF is required for myelination and regeneration of injured sciatic nerve in rodentsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 12 2000Jian-Yi Zhang Abstract Following a peripheral nerve injury, brain-derived neurotrophic factor (BDNF) and the p75 neurotrophin receptor are upregulated in Schwann cells of the Wallerian degenerating nerves. However, it is not known whether the endogenous BDNF is critical for the functions of Schwann cells and regeneration of injured nerve. Treatment with BDNF antibody was shown to retard the length of the regenerated nerve from injury site by 24%. Histological and ultrastructural examination showed that the number and density of myelinated axons in the distal side of the lesion in the antibody-treated mice was reduced by 83%. In the BDNF antibody-treated animals, there were only distorted and disorganized myelinated fibres in the injured nerve where abnormal Schwann cells and phagocytes were present. As a result of nerve degeneration in BDNF antibody-treated animals, subcellular organelles, such as mitochondria, disappeared or were disorganized and the laminal layers of the myelin sheath were loosened, separated or collapsed. Our in situ hybridization revealed that BDNF mRNA was expressed in Schwann cells in the distal segment of lesioned nerve and in the denervated muscle fibres. These results indicate that Schwann cells and muscle fibres may contribute to the sources of BDNF during regeneration and that the deprivation of endogenous BDNF results in an impairment in regeneration and myelination of regenerating axons. It is concluded that endogenous BDNF is required for peripheral nerve regeneration and remyelination after injury. [source] Fabrication and Evaluation of Chitin-Based Nerve Guidance Conduits Used to Promote Peripheral Nerve Regeneration,ADVANCED ENGINEERING MATERIALS, Issue 11 2009Yumin Yang Chitin product was prepared from the chitosan counterpart and both were found to be equally biocompatible with cultured Schwann cells. Chitin- and chitosan-based nerve guidance conduits (NGCs) were surgically implanted to bridge 10-mm-long neural defects in rat sciatic nerves. The regenerative outcome provided positive evidence that chitin- and chitosan-based NGCs produce the similar beneficial effects on peripheral nerve regeneration. [source] Retroviral labeling of Schwann cells: In vitro characterization and in vivo transplantation to improve peripheral nerve regenerationGLIA, Issue 1 2001Afshin Mosahebi Abstract Transplantation of Schwann cells (SCs) is a promising treatment modality to improve neuronal regeneration. Identification of the transplanted cells is an important step when studying the development of this method. Genetic labeling is the most stable and reliable method of cell identification, but it is still unclear whether it has deleterious effect on SC characteristics. Our aim was to achieve a stable population of SCs transduced with the lacZ gene at a high frequency using a retroviral vector in vitro, and to follow the labeled SC in vitro to assess their viability and phenotypic marker expression. Furthermore, we transplanted lacZ -labeled SCs in a conduit to repair peripheral nerve to investigate their effect on nerve regeneration in vivo. Rat and human SCs were cultured and transduced with an MFG lacZ nls marker gene, achieving a transduction rate of 80% and 70%, respectively. Rat SCs were kept in culture for 27 weeks and examined every 4 weeks for expression of lacZ, viability, and phenotypic marker expression of GFAP, p75, MHC I and II. Throughout this period, transduced rat SCs remained viable and continued to proliferate. The proportion of cells expressing lacZ dropped only by 10% and the expression of phenotypic markers remained stable. Transduced human SCs were followed up for 4 weeks in culture. They proliferated and continued to express the lacZ gene and phenotypic marker expression of GFAP and p75 was preserved. Primary culture of transduced rat SCs were transplanted, syngeneically, in a conduit to bridge a 10 mm gap in sciatic nerve and the grafts were examined after 3 weeks for the presence and participation of labeled SCs and for axonal regeneration distance. Transplanted transduced rat SCs were clearly identified, taking part in the regeneration process and enhancing the axonal regeneration rate by 100% (at the optimal concentration) compared to conduits without SCs. Thus, retroviral introduction of lacZ gene has no deleterious effect on SCs in vitro and these SCs take part and enhance nerve regeneration in vivo. GLIA 34:8,17, 2001. © 2001 Wiley-Liss, Inc. [source] Regeneration of canine peroneal nerve with the use of a polyglycolic acid,collagen tube filled with laminin-soaked collagen sponge: a comparative study of collagen sponge and collagen fibers as filling materials for nerve conduitsJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 6 2001Toshinari Toba Abstract A novel artificial nerve conduit was developed and its efficiency was evaluated on the basis of promotion of peripheral nerve regeneration across an 80-mm gap in dogs. The nerve conduit was made of a polyglycolic acid,collagen tube filled with laminin-soaked collagen sponge. Conduits filled with either sponge- or fiber-form collagen were implanted into an 80-mm gap of the peroneal nerve (five dogs for each form). Twelve months postoperatively nerve regeneration was superior in the sponge group both morphometrically (percentage of neural tissue: fiber: 39.7 ± 5.2, sponge: 43.0 ± 4.5, n=3) and electrophysiologically (fiber: CMAP 1.06 ± 0.077, SEP 1.32 ± 0.127 sponge: CMAP 1.04 ± 0.106, SEP 1.24 ± 0.197, n=5), although these differences were not statistically significant. The observed regeneration was complementary to successful results reported previously in the same model, in which collagen fibers exclusively were used. The results indicate a possible superiority of collagen sponge over collagen fibers as filling materials. In addition, the mass-producibility, superior scaffolding potential, and capacity for gradual release of soluble factors of the sponge provide make it an attractive alternative to fine fibers, which are both technologically difficult and costly to produce. This newly developed nerve conduit has the potential to enhance peripheral nerve regeneration across longer gaps commonly encountered in clinical settings. © 2001 John Wiley & Sons, Inc. J Biomed Mater Res (Appl Biomater) 58: 622,630, 2001 [source] Schwann cell delivery of neurotrophic factors for peripheral nerve regenerationJOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 2 2010Srinivas Madduri Current treatments of injured peripheral nerves often fail to mediate satisfactory functional recovery. For axonal regeneration, neurotrophic factors (NTFs) play a crucial role. Multiple NTFs and other growth-promoting factors are secreted, amongst others, by Schwann cells (SCs), which also provide cellular guidance for regenerating axons. Therefore, delivery of NTFs and transplantation of autologous or genetically modified SCs with therapeutic protein expression have been proposed. This article reviews polymer-based and cellular approaches for NTF delivery, with a focus on SCs and strategies to modulate SC gene expression. Polymer-based NTF delivery has mostly resided on nerve conduits (NC). While NC have generally provided prolonged NTF release, their therapeutic effect has remained significantly below that achieved with autologous nerve grafts. Several studies demonstrated enhanced nerve regeneration using NC seeded with SCs. The SCs have sometimes been modified genetically using non-viral or viral vectors. Whereas non-viral vectors produced poor transgene delivery, adenoviral vectors mediated high transgene transduction efficiency of SCs. Further improvements of safety and transgene expression of adenoviral vector may lead to rapid translation of pre-clinical research to clinical trials. [source] Acetyl-l-carnitine in the treatment of painful antiretroviral toxic neuropathy in human immunodeficiency virus patients: an open label studyJOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 1 2006Maurizio Osio Abstract Antiretroviral toxic neuropathy causes morbidity in human immunodeficiency virus (HIV) patients under dideoxynucleoside therapy, benefits only partially from medical therapy, and often leads to drug discontinuation. Proposed pathogeneses include a disorder of mitochondrial oxidative metabolism, eventually related to a reduction of mitochondrial DNA content, and interference with nerve growth factor activity. Carnitine is a substrate of energy production reactions in mitochondria and is involved in many anabolic reactions. Acetyl carnitine treatment promotes peripheral nerve regeneration and has neuroprotective properties and a direct analgesic role related to glutamatergic and cholinergic modulation. The aim of this study was to evaluate acetyl-l-carnitine in the treatment of painful antiretroviral toxic neuropathy in HIV patients. Twenty subjects affected by painful antiretroviral toxic neuropathy were treated with oral acetyl-l-carnitine at a dose of 2,000 mg/day for a 4-week period. Efficacy was evaluated by means of the modified Short Form McGill Pain Questionnaire with each item rated on an 11-point intensity scale at weekly intervals and by electromyography at baseline and final visit. Mean pain intensity score was significantly reduced during the study, changing from 7.35 ± 1.98 (mean ± SD) at baseline to 5.80 ± 2.63 at week 4 (p = 0.0001). Electrophysiological parameters did not significantly change between baseline and week 4. In this study, acetyl-l-carnitine was effective and well tolerated in symptomatic treatment of painful neuropathy associated with antiretroviral toxicity. On the contrary, no effect was noted on neurophysiological parameters. [source] Improvement of peripheral nerve regeneration in acellular nerve grafts with local release of nerve growth factorMICROSURGERY, Issue 4 2009Hailong Yu M.D. Previous studies have demonstrated the potential of growth factors in peripheral nerve regeneration. A method was developed for sustained delivery of nerve growth factor (NGF) for nerve repair with acellular nerve grafts to augment peripheral nerve regeneration. NGF-containing polymeric microspheres were fixed with fibrin glue around chemically extracted acellular nerve grafts for prolonged, site-specific delivery of NGF. A total of 52 Wister rats were randomly divided into four groups for treatment: autografting, NGF-treated acellular grafting, acellular grafting alone, and acellular grafting with fibrin glue. The model of a 10-mm sciatic nerve with a 10-mm gap was used to assess nerve regeneration. At the 2nd week after nerve repair, the length of axonal regeneration was longer with NGF-treated acellular grafting than acellular grafting alone and acellular grafting with fibrin glue, but shorter than autografting (P < 0.05). Sixteen weeks after nerve repair, nerve regeneration was assessed functionally and histomorphometrically. The percentage tension of the triceps surae muscles in the autograft group was 85.33 ± 5.59%, significantly higher than that of NGF-treated group, acellular graft group and fibrin-glue group, at 69.79 ± 5.31%, 64.46 ± 8.48%, and 63.35 ± 6.40%, respectively (P < 0.05). The ratio of conserved muscle-mass was greater in the NGF-treated group (53.73 ± 4.56%) than in the acellular graft (46.37 ± 5.68%) and fibrin glue groups (45.78 ± 7.14%) but lower than in the autograft group (62.54 ± 8.25%) (P < 0.05). Image analysis on histological observation revealed axonal diameter, axon number, and myelin thickness better with NGF-treated acellular grafting than with acellular grafting alone and acellular grafting with fibrin glue (P < 0.05). There were no significant differences between NGF-treated acellular grafting and autografting. This method of sustained site-specific delivery of NGF can enhance peripheral nerve regeneration across short nerve gaps repaired with acellular nerve grafts. © 2009 Wiley-Liss, Inc. Microsurgery, 2009. [source] Nerve regeneration along bioengineered scaffoldsMICROSURGERY, Issue 5 2007S. Geuna M.D. Tissue engineering has recently seen great advancements in many medical fields, including peripheral nerve reconstruction. In the rat median nerve model, we investigated nerve repair by means of bioengineered tissue scaffolds (muscle-vein-combined tubes) focusing on changes in the neuregulin-1/ErbB-receptor system which represents one of the main regulatory systems of axo-glial interaction in peripheral nerves. Repaired nerves were withdrawn at 5, 15, and 30 days postoperative and processed for morphological and retro-transcriptase polymerase chain reaction (RT-PCR) analysis. Results revealed an early and progressive increase in the expression of NRG1, isoform only, while the appearance of the , isoform of NRG1, which is normally present in peripheral nerves, was delayed. In regards to ErbB2 and ErbB3 receptors, their expression increased progressively inside the muscle-vein-combined scaffolds, though with different kinetics. Taken together, these results suggest that variations in neuregulin-1/ErbB system activation play a key role in peripheral nerve regeneration along bioengineered muscle-vein-combined scaffolds. Since similar variations are also detectable in denervated skeletal muscles, it can be hypothesized that the existence of a NRG1's autocrine/paracrine trophic loop shared by both glial and muscle fibers could be responsible for the effectiveness of muscle-vein-combined conduits for repairing nerve defects. © 2007 Wiley-Liss, Inc. Microsurgery, 2007. [source] Regeneration of peripheral nerves after clenbuterol treatment in a rat modelMUSCLE AND NERVE, Issue 12 2001Onno Frerichs MD Abstract Clenbuterol is known to act as a neuroprotective substance in the central nervous system, and also reduces muscle atrophy after denervation. The aim of this study was to evaluate its influence on peripheral nerve regeneration. The rat sciatic nerve model was used in four groups (n = 8 per group). After complete nerve transection and microsurgical coaptation, two groups received a daily oral dose of 100 ,g/kg clenbuterol and two served as controls. Regeneration was assessed clinically, histologically, and morphometrically after 4 and 6 weeks. The weight ratios of calf muscles were calculated. Histological examination showed significantly increased axon counts in the clenbuterol group and a better degree of myelination. Muscle weight ratios of the clenbuterol group were significantly increased after 6 weeks, and the animals showed improved function of the hindlimb. Thus, therapy with 100 ,g/kg clenbuterol daily after coaptation of a sciatic nerve showed a positive influence on clinical, histological, and morphometrical parameters in the rat model. The underlying mechanism remains unclear. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 1687,1691, 2001 [source] Highly Permeable Genipin-Cross-linked Gelatin Conduits Enhance Peripheral Nerve RegenerationARTIFICIAL ORGANS, Issue 12 2009Ju-Ying Chang Abstract Here we have evaluated peripheral nerve regeneration with a porous biodegradable nerve conduit (PGGC), which was made from genipin-cross-linked gelatin. To examine the effect of pores, nonporous genipin-cross-linked gelatin conduit (GGC) was considered as the control. Both the PGGC and the GGC were dark blue in appearance with a concentric and round lumina. The PGGC featured an outer surface with pores of variable size homogeneously traversing, and a partially fenestrated inner surface connected by an open trabecular meshwork. The GGC had a rough outer surface whereas its inner lumen was smooth. Both PGGCs and GGCs had similar hydrophilicity on condition of the same material and cross-linking degree. The porosity of PGGCs and GGCs was 90.8 ± 0.9% and 24.3 ± 2.9%, respectively. The maximum tensile force of the GGCs (0.12 ± 0.06 kN) exceeded that of the PGGCs (0.03 ± 0.01 kN), but the PGGCs had a higher swelling ratio than GGCs at 0.5, 1, 3, 6, 12, 24, 48, 60, 72, and 84 h after soaking in deionized water. Cytotoxic testing revealed the soaking solutions of both of the tube composites would not produce cytotoxicity to cocultured Schwann cells. After subcutaneous implantation on the dorsal side of the rat, the PGGC was degraded completely after 12 weeks of implantation whereas a thin tissue capsule was formed encapsulating the partially degraded GGC. Biodegradability of both of the tube groups and their effectiveness as a guidance channel were examined as they were used to repair a 10 mm gap in the rat sciatic nerve. As a result, fragmentation of the GGC was still seen after 12 weeks of implantation, yet the PGGC had been completely degraded. Histological observation showed that numerous myelinated axons had crossed over the gap region in the PGGCs after 8 weeks of implantation despite only few myelinated axons and unmyelinated axons mostly surrounded by Schwann cells seen in the GGCs. In addition, the regenerated nerves in the PGGCs presented a significantly higher nerve conductive velocity than those in the GGCs (P < 0.05). Thus, the PGGCs can not only offer effective aids for regenerating nerves but also accelerate favorable nerve functional recovery compared with the GGCs. [source] Electromagnetic Field Treatment of Nerve Crush Injury in a Rat Model: Effect of Signal Configuration on Functional RecoveryBIOELECTROMAGNETICS, Issue 4 2007Janet L. Walker Abstract Electromagnetic fields (EMFs) have been demonstrated to enhance mammalian peripheral nerve regeneration in vitro and in vivo. Using an EMF signal shown to enhance neurite outgrowth in vitro, we tested this field in vivo using three different amplitudes. The rat sciatic nerve was crushed. Whole body exposure was performed for 4 h/day for 5 days in a 96-turn solenoid coil controlled by a signal generator and power amplifier. The induced electric field at the target tissue consisted of a bipolar rectangular pulse, having 1 and 0.3 ms durations in each polarity, respectively. Pulse repetition rate was 2 per second. By varying the current, the coils produced fields consisting of sham (no current) and peak magnetic fields of 0.03 mT, 0.3 mT, and 3 mT, corresponding to peak induced electric fields of 1, 10, and 100 µV/cm, respectively, at the tissue target. Walking function was assessed over 43 days using video recording and measurement of the 1,5 toe-spread, using an imaging program. Comparing injured to uninjured hind limbs, mean responses were evaluated using a linear mixed statistical model. There was no difference found in recovery of the toe-spread function between any EMF treatments compared to sham. Bioelectromagnetics 28:256,263, 2007. © 2007 Wiley-Liss, Inc. [source] Pulsed electromagnetic fields induce peripheral nerve regeneration and endplate enzymatic changesBIOELECTROMAGNETICS, Issue 1 2005J.A. De Pedro Abstract An experimental study was carried out in rats with the purpose of demonstrating the capacity of pulsed electromagnetic fields (PEMFs) to stimulate regeneration of the peripheral nervous system (PNS). Wistar and Brown Norway (BN) rats were used. Direct sciatic nerve anastomoses were performed after section or allograft interposition. Treatment groups then received 4 weeks of PEMFs. Control groups received no stimulation. The evaluation of the results was carried out by quantitative morphometric analysis, demonstrating a statistically significant increase in regeneration indices (P,<,0.05) in the stimulated groups (9000,±,5000 and 4000,±,6000) compared to the non-stimulated groups (2000,±,4000 and 700,±,200). An increase of NAD specific isocitrate dehydrogenase (IDH) activity was found along with an increase in the activity of acetyl cholinesterase at the motor plate. The present study might lead to the search for new alternatives in the stimulation of axonal regenerative processes in the PNS and other possible clinical applications. Bioelectromagnetics 26:20,27, 2005. © 2004 Wiley-Liss, Inc. [source] Spider silk fibres in artificial nerve constructs promote peripheral nerve regenerationCELL PROLIFERATION, Issue 3 2008C. Allmeling Materials and methods: We compared isogenic nerve grafts to vein grafts with spider silk fibres, either alone or supplemented with Schwann cells, or Schwann cells and matrigel. Controls, consisting of veins and matrigel, were transplanted. After 6 months, regeneration was evaluated for clinical outcome, as well as for histological and morphometrical performance. Results: Nerve regeneration was achieved with isogenic nerve grafts as well as with all constructs, but not in the control group. Effective regeneration by isogenic nerve grafts and grafts containing spider silk was corroborated by diminished degeneration of the gastrocnemius muscle and by good histological evaluation results. Nerves stained for S-100 and neurofilament indicated existence of Schwann cells and axonal re-growth. Axons were aligned regularly and had a healthy appearance on ultrastructural examination. Interestingly, in contrast to recently published studies, we found that bridging an extensive gap by cell-free constructs based on vein and spider silk was highly effective in nerve regeneration. Conclusion: We conclude that spider silk is a viable guiding material for Schwann cell migration and proliferation as well as for axonal re-growth in a long-distance model for peripheral nerve regeneration. [source] | ||||||||||||||||