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Sample records for nerve cell activity

  1. Activation of sensory nerves participates in stress-induced histamine release from mast cells in rats.

    Science.gov (United States)

    Huang, Z L; Mochizuki, T; Watanabe, H; Maeyama, K

    1999-08-01

    To elucidate the mechanism by which stress induces rapid histamine release from mast cells, Wistar rats, pretreated as neonates with capsaicin, were subjected to immobilization stress for 2 h, and histamine release was measured in paws of anesthetized rats by using in vivo microdialysis after activation of sensory nerves by electrical or chemical stimulation. Immobilization stress studies indicated that in control rats stress induced a 2.7-fold increase in the level of plasma histamine compared to that in freely moving rats. Whereas pretreatment with capsaicin significantly decreased stress-induced elevation of plasma histamine. Microdialysis studies showed that electrical stimulation of the sciatic nerve resulted in a 4-fold increase of histamine release in rat paws. However, this increase was significantly inhibited in rats pretreated with capsaicin. Furthermore, injection of capsaicin into rat paw significantly increased histamine release in a dose-dependent manner. These results suggest that activation of sensory nerves participates in stress-induced histamine release from mast cells. PMID:10462124

  2. Nerve growth factor enhances the CRE-dependent transcriptional activity activated by nobiletin in PC12 cells.

    Science.gov (United States)

    Takito, Jiro; Kimura, Junko; Kajima, Koji; Uozumi, Nobuyuki; Watanabe, Makoto; Yokosuka, Akihito; Mimaki, Yoshihiro; Nakamura, Masanori; Ohizumi, Yasushi

    2016-07-01

    Prevention and treatment of Alzheimer disease are urgent problems for elderly people in developed countries. We previously reported that nobiletin, a poly-methoxylated flavone from the citrus peel, improved the symptoms in various types of animal models of memory loss and activated the cAMP responsive element (CRE)-dependent transcription in PC12 cells. Nobiletin activated the cAMP/PKA/MEK/Erk/MAPK signaling pathway without using the TrkA signaling activated by nerve growth factor (NGF). Here, we examined the effect of combination of nobiletin and NGF on the CRE-dependent transcription in PC12 cells. Although NGF alone had little effect on the CRE-dependent transcription, NGF markedly enhanced the CRE-dependent transcription induced by nobiletin. The NGF-induced enhancement was neutralized by a TrkA antagonist, K252a. This effect of NGF was effective on the early signaling event elicited by nobiletin. These results suggested that there was crosstalk between NGF and nobiletin signaling in activating the CRE-dependent transcription in PC12 cells. PMID:27128150

  3. Adipose derived stem cells and nerve regeneration

    Institute of Scientific and Technical Information of China (English)

    Alessandro Faroni; Richard JP Smith; Adam J Reid

    2014-01-01

    Injuries to peripheral nerves are common and cause life-changing problems for patients along-side high social and health care costs for society. Current clinical treatment of peripheral nerve injuries predominantly relies on sacriifcing a section of nerve from elsewhere in the body to pro-vide a graft at the injury site. Much work has been done to develop a bioengineered nerve graft, precluding sacriifce of a functional nerve. Stem cells are prime candidates as accelerators of re-generation in these nerve grafts. This review examines the potential of adipose-derived stem cells to improve nerve repair assisted by bioengineered nerve grafts.

  4. Neovibsanin B increases extracellular matrix proteins in optic nerve head cells via activation of Smad signalling pathway.

    Science.gov (United States)

    Wang, Zhen; Xu, Wei; Rong, Ao; Lin, Yan; Qiu, Xu-Ling; Qu, Shen; Lan, Xian-Hai

    2015-01-01

    The present study demonstrates the effect of neovibsanin B on the synthesis and deposition of ECM proteins and the signalling pathways used in optic nerve head (ONH) astrocytes and lamina cribrosa (LC) cells. For investigation of the signalling pathway used by neovibsanin B, ONH cells were treated with neovibsanin B. Western blot and immunostaining analyses were used to examine the phosphorylation of proteins involved in Smad and non-Smad signalling pathway. The results revealed that ONH cells on treatment with neovibsanin B showed enhanced synthesis of extracellular matrix (ECM) proteins. Neovibsanin B induced phosphorylation of canonical signalling proteins, Smad2/3. However phosphorylation of non-canonical signalling proteins, extracellular signal-regulated kinases, p38, and c-Jun N-terminal kinases (JNK) 1/2 remained unaffected. There was also increase in co-localization of pSmad2/3 with Co-Smad4 in the nucleus of ONH astrocytes and LC cells indicating activation of the canonical Smad signalling pathway. Treatment of ONH cells with SIS3, inhibitor of Smad3 phosphorylation reversed the neovibsanin B stimulated ECM expression as well as activation of canonical pathway signalling molecules. In addition, inhibition of Smad2 or Smad3 using small interfering RNA (siRNA) also suppressed neovibsanin B stimulated ECM protein synthesis in ONH astrocytes and LC cells. Thus neovibsanin B utilizes the canonical Smad signalling pathway to stimulate ECM synthesis in human ONH cells. The neovibsanin B induced ECM synthesis and activation of the canonical Smad signalling pathway may be due to its effect on transforming growth factor-β2 (TGF-β2). However, further studies are under process to understand the mechanism.

  5. Hypoxia inhibits abdominal expiratory nerve activity.

    Science.gov (United States)

    Fregosi, R F; Knuth, S L; Ward, D K; Bartlett, D

    1987-07-01

    Our purpose was to examine the influence of steady-state changes in chemical stimuli, as well as discrete peripheral chemoreceptor stimulation, on abdominal expiratory motor activity. In decerebrate, paralyzed, vagotomized, and ventilated cats that had bilateral pneumothoraces, we recorded efferent activity from a phrenic nerve and from an abdominal nerve (cranial iliohypogastric nerve, L1). All cats showed phasic expiratory abdominal nerve discharge at normocapnia [end-tidal PCO2 38 +/- 2 Torr], but small doses (2-6 mg/kg) of pentobarbital sodium markedly depressed this activity. Hyperoxic hypercapnia consistently enhanced abdominal expiratory activity and shortened the burst duration. Isocapnic hypoxia caused inhibition of abdominal nerve discharge in 11 of 13 cats. Carotid sinus nerve denervation (3 cats) exacerbated the hypoxic depression of abdominal nerve activity and depressed phrenic motor output. Stimulation of peripheral chemoreceptors with NaCN increased abdominal nerve discharge in 7 of 10 cats, although 2 cats exhibited marked inhibition. Four cats with intact neuraxis, but anesthetized with ketamine, yielded qualitatively similar results. We conclude that when cats are subjected to steady-state chemical stimuli in isolation (no interference from proprioceptive inputs), hypercapnia potentiates, but hypoxia attenuates, abdominal expiratory nerve activity. Mechanisms to explain the selective inhibition of expiratory motor activity by hypoxia are proposed, and physiological implications are discussed. PMID:3624126

  6. Histological observation on acellular nerve grafts co-cultured with Schwann cells for repairing defects of the sciatic nerve

    Institute of Scientific and Technical Information of China (English)

    Xiaohong Sun; Jiangyi Tian; Xiaojie Tong; Xu Zhang; Zheng He

    2006-01-01

    BACKGROUND: Animal experiments and clinical studies about tissue engineering method applied to repair nerve injury mainly focus on seeking ideal artificial nerve grafts, nerve conduit and seed cells. Autologous nerve, allogeneic nerve and xenogeneic nerve are used to bridge nerve defects, it is one of the methods to promote the repair of nerve injury by culturing and growing Schwann cells, which can secrete various neurotrophic factor activities, in the grafts.OBJECTIVE: To observe the effect of acellular nerve grafts co-cultured with Schwann cells in repairing defects of sciatic nerve.DESIGN: An observational comparative study.SETTING: Tissue Engineering Laboratory of China Medical University.MATERIALS: The experiment was carried out in the Tissue Engineering Laboratory of China Medical University between April 2004 and April 2005. Forty neonatal Sprague-Dawley rats of 5-8 days (either males or females) and 24 male Wistar rats of 180-220 g were provided by the experimental animal center of China Medical University.METHODS: ① Culture of Schwann cells: The bilateral sciatic nerves and branchial plexus were isolated from the 40 neonatal SD rats. The sciatic nerves were enzymatically digested with collagenase and dispase, isolatd, purified and cultured with the method of speed-difference adhersion, and identified with the SABC immunohistochemical method. ② Model establishment: In vitro Schwann cells were microinjected into 10-mm long acellular nerve grafts repairing a surgically created gap in the rat sciatic nerve.According to the different grafted methods, the animals were randomly divided into three groups: autografts (n=8), acellular nerve grafts (n=8), or acellular nerve grafts with Schwann cells (n=8). ③ The regenerated nerve fiber number and average diameter of myeline sheath after culture were statistically anlayzed.MAIN OUTCOME MEASURES: ① The regenerated nerve ultrastructure, total number and density of myelinated nerve fibers, and the thickness of

  7. Combination of Acellular Nerve Graft and Schwann Cells-Like Cells for Rat Sciatic Nerve Regeneration

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    Songtao Gao

    2014-01-01

    Full Text Available Objective. To investigate the effect of tissue engineering nerve on repair of rat sciatic nerve defect. Methods. Forty-five rats with defective sciatic nerve were randomly divided into three groups. Rats in group A were repaired by acellular nerve grafts only. Rats in group B were repaired by tissue engineering nerve. In group C, rats were repaired by autogenous nerve grafts. After six and twelve weeks, sciatic nerve functional index (SFI, neural electrophysiology (NEP, histological and transmission electron microscope observation, recovery ratio of wet weight of gastrocnemius muscle, regenerated myelinated nerve fibers number, nerve fiber diameter, and thickness of the myelin sheath were measured to assess the effect. Results. After six and twelve weeks, the recovery ratio of SFI and wet weight of gastrocnemius muscle, NEP, and the result of regenerated myelinated nerve fibers in groups B and C were superior to that of group A (P0.05. Conclusion. The tissue engineering nerve composed of acellular allogenic nerve scaffold and Schwann cells-like cells can effectively repair the nerve defect in rats and its effect was similar to that of the autogenous nerve grafts.

  8. Activation of Nerve Growth Factor-Induced Bα by Methylene-Substituted Diindolylmethanes in Bladder Cancer Cells Induces Apoptosis and Inhibits Tumor GrowthS⃞

    OpenAIRE

    Dae Cho, Sung; Lee, Syng-Ook; Chintharlapalli, Sudhakar; Abdelrahim, Maen; Khan, Shaheen; Yoon, Kyungsil; Kamat, Ashish M.; Safe, Stephen

    2010-01-01

    Nerve growth factor-induced B (NGFI-B) genes are orphan nuclear receptors, and NGFI-Bα (Nur77, TR3) is overexpressed in bladder tumors and bladder cancer cells compared with nontumorous bladder tissue. 1,1-Bis(3′-indolyl)-1-(p-methoxyphenyl)-methane (DIM-C-pPhOCH3) and 1,1-bis(3′-indolyl)-1-(p-phenyl)methane have previously been identified as activators of Nur77, and both compound...

  9. Genetic instability in nerve sheath cell tumors

    DEFF Research Database (Denmark)

    Rogatto, Silvia Regina; Casartelli, Cacilda; Rainho, Claudia Aparecida;

    1995-01-01

    by the presence of polyploid cells with inconsistent abnormalities, endoreduplications and telomeric associations resulting in dicentric chromosomes. It is probable that these cytogenetic abnormalities represent some kind of evolutionary advantage for the in vitro progression of nerve sheath tumors....

  10. Immune cell distribution and immunoglobulin levels change following sciatic nerve injury in a rat model

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    Wei Yuan

    2016-07-01

    Full Text Available Objective(s: To investigate the systemic and local immune status of two surgical rat models of sciatic nerve injury, a crushed sciatic nerve, and a sciatic nerve transection Materials and Methods:Twenty-four adult male Sprague-Dawley rats were randomly divided into three groups: sham-operation (control group, sciatic nerve crush, and sciatic nerve transaction. Sciatic nerve surgery was performed. The percentage of CD4+ cells and the CD4+/CD8+ratio were determined by flow cytometry. Serum IgM and IgG levels were analyzed by ELISA. T-cells (CD3 and macrophages (CD68 in sciatic nerve tissue sections were identified through immunohistochemistry. Results: Compared to sham-operated controls, in rats that underwent nerve injury, the percentage of CD4+ cells and the CD4+/CD8+ ratio in the peripheral blood were significantly  decreased 7 days after surgery, serum IgM levels were increased 14 days after surgery, and serum IgG levels were increased 21 days after surgery. There were a large number of CD3+ cells and a small number of CD68+ cells in sciatic nerve tissue sections 21 days after surgery, indicating T-cell and macrophage activation and infiltration. Local IgG deposition was also detected at the nerve injury site 21 days after surgery. Conclusion: Rat humoral and cellular immune status changed following sciatic nerve injury, particularly with regard to the cellular immune response at the nerve injury site.

  11. Immune cell distribution and immunoglobulin levels change following sciatic nerve injury in a rat model

    Science.gov (United States)

    Yuan, Wei; Feng, Xinhong

    2016-01-01

    Objective(s): To investigate the systemic and local immune status of two surgical rat models of sciatic nerve injury, a crushed sciatic nerve, and a sciatic nerve transection Materials and Methods: Twenty-four adult male Sprague-Dawley rats were randomly divided into three groups: sham-operation (control group), sciatic nerve crush, and sciatic nerve transaction. Sciatic nerve surgery was performed. The percentage of CD4+ cells and the CD4+/CD8+ratio were determined by flow cytometry. Serum IgM and IgG levels were analyzed by ELISA. T-cells (CD3) and macrophages (CD68) in sciatic nerve tissue sections were identified through immunohistochemistry. Results: Compared to sham-operated controls, in rats that underwent nerve injury, the percentage of CD4+ cells and the CD4+/CD8+ ratio in the peripheral blood were significantly decreased 7 days after surgery, serum IgM levels were increased 14 days after surgery, and serum IgG levels were increased 21 days after surgery. There were a large number of CD3+ cells and a small number of CD68+ cells in sciatic nerve tissue sections 21 days after surgery, indicating T-cell and macrophage activation and infiltration. Local IgG deposition was also detected at the nerve injury site 21 days after surgery. Conclusion: Rat humoral and cellular immune status changed following sciatic nerve injury, particularly with regard to the cellular immune response at the nerve injury site.

  12. Peripheral nerve injury induces glial activation in primary motor cortex

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    Julieta Troncoso

    2015-02-01

    Full Text Available Preliminary evidence suggests that peripheral facial nerve injuries are associated with sensorimotor cortex reorganization. We have characterized facial nerve lesion-induced structural changes in primary motor cortex layer 5 pyramidal neurons and their relationship with glial cell density using a rodent facial paralysis model. First, we used adult transgenic mice expressing green fluorescent protein in microglia and yellow fluorescent protein in pyramidal neurons which were subjected to either unilateral lesion of the facial nerve or sham surgery. Two-photon excitation microscopy was then used for evaluating both layer 5 pyramidal neurons and microglia in vibrissal primary motor cortex (vM1. It was found that facial nerve lesion induced long-lasting changes in dendritic morphology of vM1 layer 5 pyramidal neurons and in their surrounding microglia. Pyramidal cells’ dendritic arborization underwent overall shrinkage and transient spine pruning. Moreover, microglial cell density surrounding vM1 layer 5 pyramidal neurons was significantly increased with morphological bias towards the activated phenotype. Additionally, we induced facial nerve lesion in Wistar rats to evaluate the degree and extension of facial nerve lesion-induced reorganization processes in central nervous system using neuronal and glial markers. Immunoreactivity to NeuN (neuronal nuclei antigen, GAP-43 (growth-associated protein 43, GFAP (glial fibrillary acidic protein, and Iba 1 (Ionized calcium binding adaptor molecule 1 were evaluated 1, 3, 7, 14, 28 and 35 days after either unilateral facial nerve lesion or sham surgery. Patches of decreased NeuN immunoreactivity were found bilaterally in vM1 as well as in primary somatosensory cortex (CxS1. Significantly increased GAP-43 immunoreactivity was found bilaterally after the lesion in hippocampus, striatum, and sensorimotor cortex. One day after lesion GFAP immunoreactivity increased bilaterally in hippocampus, subcortical white

  13. Sericin protects against diabetes-induced injuries in sciatic nerve and related nerve cells

    Institute of Scientific and Technical Information of China (English)

    Chengjun Song; Zhenjun Yang; Meirong Zhong; Zhihong Chen

    2013-01-01

    Sericin from discarded silkworm cocoons of silk reeling has been used in different fields, such as cosmetology, skin care, nutrition, and oncology. The present study established a rat model of type 2 diabetes by consecutive intraperitoneal injections of low-dose (25 mg/kg) streptozotocin. After intragastrical perfusion of sericin for 35 days, blood glucose levels significantly declined, and the expression of neurofilament protein in the sciatic nerve and nerve growth factor in L4–6 spinal ganglion and anterior horn cells significantly increased. However, the expression of neuropeptide Y in spinal ganglion and anterior horn cells significantly decreased in model rats. These findings indicate that sericin protected the sciatic nerve and related nerve cells against injury in a rat type 2 diabetic model by upregulating the expression of neurofilament protein in the sciatic nerve and nerve growth factor in spinal ganglion and anterior horn cells, and downregulating the expression of neuropeptide Y in spinal ganglion and anterior horn cells.

  14. [Clinical application of skin sympathetic nerve activity].

    Science.gov (United States)

    Iwase, Satoshi

    2009-03-01

    Skin sympathetic nerve activity (SSNA) is microneurographically recorded from the skin nerve fascicle in the peripheral nerves. It is characterized by the following features: 1) irregular, pulse asynchronous, burst activity with respiratory variation, 2) burst activity followed by vasoconstriction and/or sweating, 3) elicited by mental stress and arousal stimuli, e.g., sound, pain, electric stimulation, 4) burst with longer duration as compared with sympathetic outflow to muscles, and 5) burst activity following sudden inspiratory action. It comprises vasoconstrictor (VC) and sudomotor(SM) activity, as well as vasodilator (VD) activity. VC and SM discharge independently, whereas VD is the same activity with different neurotransmission. The VC and SM are differentiated by effector response, e.g., laser Doppler flowmetry and skin potential changes. SSNA function in thermoregulation in the human body; however it is also elicited by mental stress. SSNA is the lowest at thermoneutral ambient temperature (approximately 27 degrees C), and is enhanced in the pressence of ambient warm and cool air. The burst amplitude is well-correlated to both skin blood flow reduction rate or sweat rate change. The clinical application of SSNA comprises the following: 1) clarification of sweating phenomenon, 2) clarification and diagnosis of anhidrosis, 3) clarification and diagnosis of hyperhidrosis, 4) clarification of thermoregulatory function and diagnosis of thermoregulatory disorder, 5) clarification of pathophysiology and diagnosis of vascular diseases, e.g., Raynaud and Buerger diseases. 6) clarification of the relation between cognitive function and SSNA and 7) determination of pharmacological effect attributable to change in neuroeffector responses. PMID:19301594

  15. Calcium Signaling in Mitral Cell Dendrites of Olfactory Bulbs of Neonatal Rats and Mice during Olfactory Nerve Stimulation and Beta-Adrenoceptor Activation

    Science.gov (United States)

    Yuan, Qi; Mutoh, Hiroki; Debarbieux, Franck; Knopfel, Thomas

    2004-01-01

    Synapses formed by the olfactory nerve (ON) provide the source of excitatory synaptic input onto mitral cells (MC) in the olfactory bulb. These synapses, which relay odor-specific inputs, are confined to the distally tufted single primary dendrites of MCs, the first stage of central olfactory processing. Beta-adrenergic modulation of electrical…

  16. Dixdc1 targets CyclinD1 and p21 via PI3K pathway activation to promote Schwann cell proliferation after sciatic nerve crush.

    Science.gov (United States)

    Wu, Weijie; Liu, Qingqing; Liu, Yuxi; Yu, Zhaohui; Wang, Youhua

    2016-09-16

    Dixdc1 (DIX domain containing-1), the mammalian homolog of Ccd1 (Coiled-coil-Dishevelled-Axin1), is a protein containing a coiled-coil domain and a Dishevelled-Axin (DIX) domain. As a novel component of the Wnt pathway, Dixdc1 has been reported to be able to promote neural progenitor proliferation and neuronal differentiation via Wnt/β-catenin signaling. But there still remains something unknown about Dixdc1 distribution and functions in the lesion and regeneration of the peripheral nervous system (PNS), so we tried to investigate dynamic changes of Dixdc1 expression in a rat sciatic nerve crush (SNC) model in this study. First of all, we detected SNC-induced increased levels of Dixdc1 in Schwann cells and interestingly identified parallel expression of PCNA (proliferation cell nuclear antigen) with Dixdc1. Besides, we observed up-regulated Dixdc1 during the process of TNF-α-induced Schwann cell proliferation. Also, we discovered that Dixdc1 could promote G1-S phase transition accompanied with the up-regulation of CyclinD1 and down-regulation of p21. More importantly, enhanced effects of Dixdc1 on cell proliferation were confirmed to be associated with PI3K activation. Not only blocking of the PI3K but Dixdc1 knockdown led to significantly decreased ability for proliferation, as well as down-regulation of CyclinD1 and up-regulation of p21. In summary, these data demonstrated that Dixdc1 might participate in Schwann cell proliferation by targeting CyclinD1 and p21 at least partially through the PI3K/AKT activation. PMID:27521891

  17. Highly Sensitive and Selective Immuno-capture/Electrochemical Assay of Acetylcholinesterase Activity in Red Blood Cells: A Biomarker of Exposure to Organophosphorus Pesticides and Nerve Agents

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Aiqiong; Du, Dan; Lin, Yuehe

    2012-02-09

    Acetylcholinesterase (AChE) enzyme activity in red blood cells (RBCs) is a useful biomarker for biomonitoring of exposures to organophosphorus (OP) pesticides and chemical nerve agents. In this paper, we reported a new method for AChE activity assay based on selective immuno-capture of AChE from biological samples followed by enzyme activity assay of captured AChE using a disposable electrochemical sensor. The electrochemical sensor is based on multiwalled carbon nanotubes-gold nanocomposites (MWCNTs-Au) modified screen printed carbon electrode (SPCE). Upon the completion of immunoreaction, the target AChE (including active and inhibited) is captured onto the electrode surface and followed by an electrochemical detection of enzymatic activity in the presence of acetylthiocholine. A linear response is obtained over standard AChE concentration range from 0.1 to 10 nM. To demonstrate the capability of this new biomonitoring method, AChE solutions dosed with different concentration of paraoxon were used to validate the new AChE assay method. AChE inhibition in OP dosed solutions was proportional to its concentration from 0.2 to 50 nM. The new AChE activity assay method for biomonitoring of OP exposure was further validated with in-vitro paraoxon-dosed RBC samples. The established electrochemical sensing platform for AChE activity assay not only avoids the problem of overlapping substrate specificity with esterases by using selective antibody, but also eliminates potential interference from other electroactive species in biological samples. It offers a new approach for sensitive, selective, and rapid AChE activity assay for biomonitoring of exposures to OPs.

  18. Cell proliferation and apoptosis in optic nerve and brain integration centers of adult troutOncorhynchus mykiss after optic nerve injury

    Institute of Scientific and Technical Information of China (English)

    Evgeniya V Pushchina; Sachin Shukla; Anatoly A Varaksin; Dmitry K Obukhov

    2016-01-01

    Fishes have remarkable ability to effectively rebuild the structure of nerve cells and nerve ifbers after central nervous system injury. However, the underlying mechanism is poorly understood. In order to address this issue, we investigated the proliferation and apoptosis of cells in contralateral and ipsilateral optic nerves, after stab wound injury to the eye of an adult troutOncorhynchus mykiss. Heterogenous population of proliferating cells was investigated at 1 week after injury. TUNEL labeling gave a qualitative and quantita-tive assessment of apoptosis in the cells of optic nerve of trout 2 days after injury. After optic nerve injury, apoptotic response was investigated, and mass patterns of cell migration were found. The maximal con-centration of apoptotic bodies was detected in the areas of mass clumps of cells. It is probably indicative of massive cell death in the area of high phagocytic activity of macrophages/microglia. At 1 week after optic nerve injury, we observed nerve cell proliferation in the trout brain integration centers: the cerebellum and the optic tectum. In the optic tectum, proliferating cell nuclear antigen (PCNA)-immunopositive radial glia-like cells were identified. Proliferative activity of nerve cells was detected in the dorsal proliferative (matrix) area of the cerebellum and in parenchymal cells of the molecular and granular layers whereas local clusters of undifferentiated cells which formed neurogenic niches were observed in both the optic tectum and cerebellum after optic nerve injury.In vitro analysis of brain cells of trout showed that suspension cells compared with monolayer cells retain higher proliferative activity, as evidenced by PCNA immunolabeling. Phase contrast observation showed mitosis in individual cells and the formation of neurospheres which gradually increased during 1–4 days of culture. The present ifndings suggest that trout can be used as a novel model for studying neuronal regeneration.

  19. Reflex effects of aerosolized histamine on phrenic nerve activity.

    OpenAIRE

    Pack, A I; Hertz, B C; Ledlie, J F; Fishman, A. P.

    1982-01-01

    Studies were conducted in anesthetized, paralyzed dogs on the effect of aerosolized histamine on phrenic nerve activity. The paralyzed dogs were ventilated in phase with their recorded phrenic nerve activity at a constant inspiratory flow-rate, using a cycle-triggered ventilator. Phrenic nerve activity was measured before and during administration of aerosolized histamine while the inspiratory flow-rate and arterial blood gases were kept constant. In addition, before and after histamine, phre...

  20. Pulp Fibroblasts Control Nerve Regeneration through Complement Activation.

    Science.gov (United States)

    Chmilewsky, F; About, I; Chung, S-H

    2016-07-01

    Dentin-pulp regeneration is closely linked to the presence of nerve fibers in the pulp and to the healing mechanism by sprouting of the nerve fiber's terminal branches beneath the carious injury site. However, little is known about the initial mechanisms regulating this process in carious teeth. It has been recently demonstrated that the complement system activation, which is one of the first immune responses, contributes to tissue regeneration through the local production of anaphylatoxins such as C5a. While few pulp fibroblasts in intact teeth and in untreated fibroblast cultures express the C5a receptor (C5aR), here we show that all dental pulp fibroblasts, localized beneath the carious injury site, do express this receptor. This observation is consistent with our in vitro results, which showed expression of C5aR in lipoteichoic acid-stimulated pulp fibroblasts. The interaction of C5a, produced after complement synthesis and activation from pulp fibroblasts, with the C5aR of these cells mediated the local brain-derived neurotropic factor (BDNF) secretion. Overall, this activation guided the neuronal growth toward the lipoteichoic acid-stimulated fibroblasts. Thus, our findings highlight a new mechanism in one of the initial steps of the dentin-pulp regeneration process, linking pulp fibroblasts to the nerve sprouting through the complement system activation. This may provide a useful future therapeutic tool in targeting the fibroblasts in the dentin-pulp regeneration process. PMID:27053117

  1. Hypoxia-induced cell death and changes in hypoxia-inducible factor-1 activity in PC12 cells upon exposure to nerve growth factor.

    Science.gov (United States)

    Charlier, Nico; Leclere, Norbert; Felderhoff, Ursula; Heldt, Julia; Kietzmann, Thomas; Obladen, Michael; Gross, Johann

    2002-07-15

    The transcription factor hypoxia-inducible factor-1 (HIF-1) strongly contributes to the expression of adaptive genes under hypoxic conditions. In addition, HIF-1 has been implicated in the regulation of delayed neuronal cell death. Suspension-grown and adherent PC12 cells treated with NGF were used as an experimental model for studying the relationship between hypoxia-induced cell death and activation of HIF-1. Cell damage was assessed by flow cytometry of double-stained (Annexin V and propidiumiodide) cells, and by analysis of the overall death parameters LDH and mitochondrial dehydrogenase. In parallel, cells were transfected with a control and a three-hypoxia-responsive-elements (HRE)-containing vector and HIF-1-driven luciferase activity was determined. Exposure of NGF-treated PC12 cells to hypoxia resulted in a higher cell death rate when compared to untreated controls. PC12 cells exposed for 2 days to NGF exhibited a decrease of HIF-1 activity up to a factor of ten. This decrease may contribute to the enhanced hypoxia-induced cell death via reduced expression of HIF-1alpha-regulated genes responsible for adaptation to hypoxia, like those for glucose transport proteins and enzymes of the glycolytic chain. The decrease in HIF-1 activity and the increase in hypoxia sensitivity may suggest that NGF act as an hierarchically organized signaling molecule.

  2. Combination of Acellular Nerve Graft and Schwann Cells-Like Cells for Rat Sciatic Nerve Regeneration

    OpenAIRE

    Songtao Gao; Yan Zheng; Qiqing Cai; Zhansheng Deng; Weitao Yao; Jiaqiang Wang; Xin Wang; Peng Zhang

    2014-01-01

    Objective. To investigate the effect of tissue engineering nerve on repair of rat sciatic nerve defect. Methods. Forty-five rats with defective sciatic nerve were randomly divided into three groups. Rats in group A were repaired by acellular nerve grafts only. Rats in group B were repaired by tissue engineering nerve. In group C, rats were repaired by autogenous nerve grafts. After six and twelve weeks, sciatic nerve functional index (SFI), neural electrophysiology (NEP), histological and tra...

  3. Selective activation of the human tibial and common peroneal nerves with a flat interface nerve electrode

    Science.gov (United States)

    Schiefer, M. A.; Freeberg, M.; Pinault, G. J. C.; Anderson, J.; Hoyen, H.; Tyler, D. J.; Triolo, R. J.

    2013-10-01

    Objective. Electrical stimulation has been shown effective in restoring basic lower extremity motor function in individuals with paralysis. We tested the hypothesis that a flat interface nerve electrode (FINE) placed around the human tibial or common peroneal nerve above the knee can selectively activate each of the most important muscles these nerves innervate for use in a neuroprosthesis to control ankle motion. Approach. During intraoperative trials involving three subjects, an eight-contact FINE was placed around the tibial and/or common peroneal nerve, proximal to the popliteal fossa. The FINE's ability to selectively recruit muscles innervated by these nerves was assessed. Data were used to estimate the potential to restore active plantarflexion or dorsiflexion while balancing inversion and eversion using a biomechanical simulation. Main results. With minimal spillover to non-targets, at least three of the four targets in the tibial nerve, including two of the three muscles constituting the triceps surae, were independently and selectively recruited in all subjects. As acceptable levels of spillover increased, recruitment of the target muscles increased. Selective activation of muscles innervated by the peroneal nerve was more challenging. Significance. Estimated joint moments suggest that plantarflexion sufficient for propulsion during stance phase of gait and dorsiflexion sufficient to prevent foot drop during swing can be achieved, accompanied by a small but tolerable inversion or eversion moment.

  4. Structure-activity relationship of nerve-highlighting fluorophores.

    Directory of Open Access Journals (Sweden)

    Summer L Gibbs

    Full Text Available Nerve damage is a major morbidity associated with numerous surgical interventions. Yet, nerve visualization continues to challenge even the most experienced surgeons. A nerve-specific fluorescent contrast agent, especially one with near-infrared (NIR absorption and emission, would be of immediate benefit to patients and surgeons. Currently, there are only three classes of small molecule organic fluorophores that penetrate the blood nerve barrier and bind to nerve tissue when administered systemically. Of these three classes, the distyrylbenzenes (DSBs are particularly attractive for further study. Although not presently in the NIR range, DSB fluorophores highlight all nerve tissue in mice, rats, and pigs after intravenous administration. The purpose of the current study was to define the pharmacophore responsible for nerve-specific uptake and retention, which would enable future molecules to be optimized for NIR optical properties. Structural analogs of the DSB class of small molecules were synthesized using combinatorial solid phase synthesis and commercially available building blocks, which yielded more than 200 unique DSB fluorophores. The nerve-specific properties of all DSB analogs were quantified using an ex vivo nerve-specific fluorescence assay on pig and human sciatic nerve. Results were used to perform quantitative structure-activity relationship (QSAR modeling and to define the nerve-specific pharmacophore. All DSB analogs with positive ex vivo fluorescence were tested for in vivo nerve specificity in mice to assess the effect of biodistribution and clearance on nerve fluorescence signal. Two new DSB fluorophores with the highest nerve to muscle ratio were tested in pigs to confirm scalability.

  5. Pre-differentiation of mesenchymal stromal cells in combination with a microstructured nerve guide supports peripheral nerve regeneration in the rat sciatic nerve model.

    Science.gov (United States)

    Boecker, Arne Hendrik; van Neerven, Sabien Geraldine Antonia; Scheffel, Juliane; Tank, Julian; Altinova, Haktan; Seidensticker, Katrin; Deumens, Ronald; Tolba, Rene; Weis, Joachim; Brook, Gary Anthony; Pallua, Norbert; Bozkurt, Ahmet

    2016-02-01

    Many bioartificial nerve guides have been investigated pre-clinically for their nerve regeneration-supporting function, often in comparison to autologous nerve transplantation, which is still regarded as the current clinical gold standard. Enrichment of these scaffolds with cells intended to support axonal regeneration has been explored as a strategy to boost axonal regeneration across these nerve guides Ansselin et al. (1998). In the present study, 20 mm rat sciatic nerve defects were implanted with a cell-seeded microstructured collagen nerve guide (Perimaix) or an autologous nerve graft. Under the influence of seeded, pre-differentiated mesenchymal stromal cells, axons regenerated well into the Perimaix nerve guide. Myelination-related parameters, like myelin sheath thickness, benefitted from an additional seeding with pre-differentiated mesenchymal stromal cells. Furthermore, both the number of retrogradely labelled sensory neurons and the axon density within the implant were elevated in the cell-seeded scaffold group with pre-differentiated mesenchymal stromal cells. However, a pre-differentiation had no influence on functional recovery. An additional cell seeding of the Perimaix nerve guide with mesenchymal stromal cells led to an extent of functional recovery, independent of the differentiation status, similar to autologous nerve transplantation. These findings encourage further investigations on pre-differentiated mesenchymal stromal cells as a cellular support for peripheral nerve regeneration. PMID:26296589

  6. Platelet-rich plasma-induced bone marrow mesenchymal stem cells versus autologous nerve grafting for sciatic nerve repair

    Institute of Scientific and Technical Information of China (English)

    Changsuo Xia; Yajuan Li; Wen Cao; Zhaohua Yu

    2010-01-01

    Autologous nerve grafting is the gold standard of peripheral nerve repair.We previously showed that autologous platelet-rich plasma(PRP)contains high concentrations of growth factors and can induce in vitro cultured bone marrow mesenchymal stem cells(BMSCs)to differentiate into Schwann cells.Here we used PRP-induced BMSCs combined with chemically extracted acellular nerves to repair sciatic nerve defects and compared the effect with autologous nerve grafting.The BMSCs and chemically extracted acellular nerve promoted target muscle wet weight restoration,motor nerve conduction velocity,and axonal and myelin sheath regeneration,with similar effectiveness to autologous nerve grafting.This finding suggests that PRP induced BMSCs can be used to repair peripheral nerve defects.

  7. [Research Progress in Seeding Cells of Peripheral Nerve].

    Science.gov (United States)

    Shi, Gengqiang; Hu, Yi

    2015-04-01

    Seeding cells play an important role in the peripheral nerve damage repair. Seeding cells studied conse- quently in peripheral nerve are Schwann cells, bone marrow mesenchymal stem cells and neural stem cells. Schwann cells, the first seeding cells, are various unique glial cells in the peripheral nervous system, which can form the myelin sheath for insulation and package of the neuron projecting axons in the peripheral nervous system so that the conduction velocity of the nerve signal was accelerated. It can be proved that Schwann cells played an important role in the maintenance of peripheral nerve function and in the regeneration process after peripheral nerve injury. The second, bone marrow mesenchymal stem cells are the various mesenchymal stem cells mainly exist in the systemic connective tissues and organs. These functional stem cells are often studied at present, and it has been found that they have exuberant proliferation and differentiation potentials. Neural stem cells, mentioned the third in sequence, are the kind of pluripotent cells with multi-directional differentiation, which could conduct the self-renewal function, and generate and differentiate neurons, astrocytes and oligodendrocytes through asymmetric cell division. These three types of seed cells are discussed in this paper. PMID:26211274

  8. Exposure to nerve growth factor worsens nephrotoxic effect induced by Cyclosporine A in HK-2 cells.

    Directory of Open Access Journals (Sweden)

    Donatella Vizza

    Full Text Available Nerve growth factor is a neurotrophin that promotes cell growth, differentiation, survival and death through two different receptors: TrkA(NTR and p75(NTR. Nerve growth factor serum concentrations increase during many inflammatory and autoimmune diseases, glomerulonephritis, chronic kidney disease, end-stage renal disease and, particularly, in renal transplant. Considering that nerve growth factor exerts beneficial effects in the treatment of major central and peripheral neurodegenerative diseases, skin and corneal ulcers, we asked whether nerve growth factor could also exert a role in Cyclosporine A-induced graft nephrotoxicity. Our hypothesis was raised from basic evidence indicating that Cyclosporine A-inhibition of calcineurin-NFAT pathway increases nerve growth factor expression levels. Therefore, we investigated the involvement of nerve growth factor and its receptors in the damage exerted by Cyclosporine A in tubular renal cells, HK-2. Our results showed that in HK-2 cells combined treatment with Cyclosporine A + nerve growth factor induced a significant reduction in cell vitality concomitant with a down-regulation of Cyclin D1 and up-regulation of p21 levels respect to cells treated with Cyclosporine A alone. Moreover functional experiments showed that the co-treatment significantly up-regulated human p21promoter activity by involvement of the Sp1 transcription factor, whose nuclear content was negatively regulated by activated NFATc1. In addition we observed that the combined exposure to Cyclosporine A + nerve growth factor promoted an up-regulation of p75 (NTR and its target genes, p53 and BAD leading to the activation of intrinsic apoptosis. Finally, the chemical inhibition of p75(NTR down-regulated the intrinsic apoptotic signal. We describe two new mechanisms by which nerve growth factor promotes growth arrest and apoptosis in tubular renal cells exposed to Cyclosporine A.

  9. Early interfaced neural activity from chronic amputated nerves

    Directory of Open Access Journals (Sweden)

    Kshitija Garde

    2009-05-01

    Full Text Available Direct interfacing of transected peripheral nerves with advanced robotic prosthetic devices has been proposed as a strategy for achieving natural motor control and sensory perception of such bionic substitutes, thus fully functionally replacing missing limbs in amputees. Multi-electrode arrays placed in the brain and peripheral nerves have been used successfully to convey neural control of prosthetic devices to the user. However, reactive gliosis, micro hemorrhages, axonopathy and excessive inflammation, currently limit their long-term use. Here we demonstrate that enticement of peripheral nerve regeneration through a non-obstructive multi-electrode array, after either acute or chronic nerve amputation, offers a viable alternative to obtain early neural recordings and to enhance long-term interfacing of nerve activity. Non restrictive electrode arrays placed in the path of regenerating nerve fibers allowed the recording of action potentials as early as 8 days post-implantation with high signal-to-noise ratio, as long as 3 months in some animals, and with minimal inflammation at the nerve tissue-metal electrode interface. Our findings suggest that regenerative on-dependent multi-electrode arrays of open design allow the early and stable interfacing of neural activity from amputated peripheral nerves and might contribute towards conveying full neural control and sensory feedback to users of robotic prosthetic devices. .

  10. Mesencephalic stimulation elicits inhibition of phrenic nerve activity in cat.

    Science.gov (United States)

    Gallman, E A; Lawing, W L; Millhorn, D E

    1991-05-01

    1. Previous work from this laboratory has indicated that the mesencephalon is the anatomical substrate for a mechanism capable of inhibiting central respiratory drive in glomectomized cats for periods of up to 1 h or more following brief exposure to systemic hypoxia; phrenic nerve activity was used as an index of central respiratory drive. 2. The present study was undertaken to further localize the region responsible for the observed post-hypoxic inhibition of respiratory drive. We studied the phrenic nerve response to stimulations of the mesencephalon in anaesthetized, paralysed peripherally chemo-denervated cats with end-expired PCO2 and body temperature servo-controlled. 3. Stimulations of two types were employed. Electrical stimulation allowed rapid determination of sites from which phrenic inhibition could be elicited. Microinjections of excitatory amino acids were used subsequently in order to confine excitation to neuronal cell bodies and not axons of passage. 4. Stimulation of discrete regions of the ventromedial aspect of the mesencephalon in the vicinity of the red nucleus produced substantial inhibition of phrenic activity which lasted up to 45 min. Stimulation of other areas of the mesencephalon either produced no phrenic inhibition or resulted in a slight stimulation of phrenic activity. 5. The results are discussed in the context of the central respiratory response to hypoxia. PMID:1676420

  11. Identified nerve cells and insect behavior.

    Science.gov (United States)

    Comer, C M; Robertson, R M

    2001-03-01

    Studies of insect identified neurons over the past 25 years have provided some of the very best data on sensorimotor integration; tracing information flow from sensory to motor networks. General principles have emerged that have increased the sophistication with which we now understand both sensory processing and motor control. Two overarching themes have emerged from studies of identified sensory interneurons. First, within a species, there are profound differences in neuronal organization associated with both the sex and the social experience of the individual. Second, single neurons exhibit some surprisingly rich examples of computational sophistication in terms of (a) temporal dynamics (coding superimposed upon circadian and shorter-term rhythms), and also (b) what Kenneth Roeder called "neural parsimony": that optimal information can be encoded, and complex acts of sensorimotor coordination can be mediated, by small ensembles of cells. Insect motor systems have proven to be relatively complex, and so studies of their organization typically have not yielded completely defined circuits as are known from some other invertebrates. However, several important findings have emerged. Analysis of neuronal oscillators for rhythmic behavior have delineated a profound influence of sensory feedback on interneuronal circuits: they are not only modulated by feedback, but may be substantially reconfigured. Additionally, insect motor circuits provide potent examples of neuronal restructuring during an organism's lifetime, as well as insights on how circuits have been modified across evolutionary time. Several areas where future advances seem likely to occur include: molecular genetic analyses, neuroecological syntheses, and neuroinformatics--the use of digital resources to organize databases with information on identified nerve cells and behavior. PMID:11163685

  12. Rapamycin promotes Schwann cell migration and nerve growth factor secretion

    Institute of Scientific and Technical Information of China (English)

    Fang Liu; Haiwei Zhang; Kaiming Zhang; Xinyu Wang; Shipu Li; Yixia Yin

    2014-01-01

    Rapamycin, similar to FK506, can promote neural regeneration in vitro. We assumed that the mechanisms of action of rapamycin and FK506 in promoting peripheral nerve regeneration were similar. This study compared the effects of different concentrations of rapamycin and FK506 on Sc hwann cells and investigated effects and mechanisms of rapamycin on improving peripheral nerve regeneration. Results demonstrated that the lowest rapamycin concentration (1.53 nmol/L) more signiifcantly promoted Schwann cell migration than the highest FK506 concentration (100μmol/L). Rapamycin promoted the secretion of nerve growth factors and upregulated growth-associated protein 43 expression in Schwann cells, but did not signiifcantly affect Schwann cell proliferation. Therefore, rapamycin has potential application in peripheral nerve regeneration therapy.

  13. Mesenchymal Stem Cells Enhance Nerve Regeneration in a Rat Sciatic Nerve Repair and Hindlimb Transplant Model

    Science.gov (United States)

    Cooney, Damon S.; Wimmers, Eric G.; Ibrahim, Zuhaib; Grahammer, Johanna; Christensen, Joani M.; Brat, Gabriel A.; Wu, Lehao W.; Sarhane, Karim A.; Lopez, Joseph; Wallner, Christoph; Furtmüller, Georg J.; Yuan, Nance; Pang, John; Sarkar, Kakali; Lee, W. P. Andrew; Brandacher, Gerald

    2016-01-01

    This study investigates the efficacy of local and intravenous mesenchymal stem cell (MSC) administration to augment neuroregeneration in both a sciatic nerve cut-and-repair and rat hindlimb transplant model. Bone marrow-derived MSCs were harvested and purified from Brown-Norway (BN) rats. Sciatic nerve transections and repairs were performed in three groups of Lewis (LEW) rats: negative controls (n = 4), local MSCs (epineural) injection (n = 4), and systemic MSCs (intravenous) injection (n = 4). Syngeneic (LEW-LEW) (n = 4) and allogeneic (BN-LEW) (n = 4) hindlimb transplants were performed and assessed for neuroregeneration after local or systemic MSC treatment. Rats undergoing sciatic nerve cut-and-repair and treated with either local or systemic injection of MSCs had significant improvement in the speed of recovery of compound muscle action potential amplitudes and axon counts when compared with negative controls. Similarly, rats undergoing allogeneic hindlimb transplants treated with local injection of MSCs exhibited significantly increased axon counts. Similarly, systemic MSC treatment resulted in improved nerve regeneration following allogeneic hindlimb transplants. Systemic administration had a more pronounced effect on electromotor recovery while local injection was more effective at increasing fiber counts, suggesting different targets of action. Local and systemic MSC injections significantly improve the pace and degree of nerve regeneration after nerve injury and hindlimb transplantation. PMID:27510321

  14. Electron microscopic study of the myelinated nerve fibres and the perineurial cell basement membrane in the diabetic human peripheral nerves

    International Nuclear Information System (INIS)

    To study the quantitative and ultrastructural changes in myelinated nerve fibers and the basement membranes of the perineurial cells in diabetic nerves. The study was performed at the Department of Anatomy, Faculty of Medicine, King Abdul-Aziz University, Jeddah, Saudi Arabia from 2003 to 2005. Human sural nerves were obtained from 15 lower limbs and 5 diabetic nerve biopsies. The total mean and density of myelinated nerve fibers per fascicle were calculated, with density of microtubules and mitochondria in the axoplasm. The number of the perineurial cell basement membrane layers was counted, and thickness of the basement membrane was measured. Among the 15 diabetic and 5 normal human sural nerves, the average diameters, number and surface area of myelinated nerve fibers and axonal microtubules density were found to be less in diabetic nerves. Mitochondrial density was higher in diabetic axons. Thickness of the perineurial cell basement membrane had a greater mean, but the number of perineurial cell layers was less than that of the diabetic group. The inner cellular layer of the perineurium of the diabetic nerves contained large vacuoles containing electron-dense degenerated myelin. A few specimens showed degenerated myelinated nerve fibers, while others showed recovering ones. Retracted axoplasms were encountered with albumin extravasation. Diabetes caused an increase in perineurial permeability. The diabetic sural nerve showed marked decrease in the myelinated nerve fibres, increase degenerated mitochondria, and decreased microtubules. (author)

  15. Receptor-mediated regional sympathetic nerve activation by leptin.

    OpenAIRE

    Haynes, W G; Morgan, D A; Walsh, S A; Mark, A L; Sivitz, W I

    1997-01-01

    Leptin is a peptide hormone produced by adipose tissue which acts centrally to decrease appetite and increase energy expenditure. Although leptin increases norepinephrine turnover in thermogenic tissues, the effects of leptin on directly measured sympathetic nerve activity to thermogenic and other tissues are not known. We examined the effects of intravenous leptin and vehicle on sympathetic nerve activity to brown adipose tissue, kidney, hindlimb, and adrenal gland in anesthetized Sprague-Da...

  16. Centrally administered glucagon stimulates sympathetic nerve activity in rat.

    Science.gov (United States)

    Krzeski, R; Czyzyk-Krzeska, M F; Trzebski, A; Millhorn, D E

    1989-12-18

    The effect of pancreatic glucagon given intravenously, intracerebroventricularly and microinjected into the nucleus of the solitary tract on sympathetic activity in the cervical trunk and adrenal nerve was examined in rat. In each case glucagon caused a relatively long-lasting substantial increase in discharge of both nerves. This finding shows that glucagon can act centrally to stimulate sympathetic activity. The most probable site for the sympathoexcitatory effect of glucagon is the nucleus of the solitary tract. PMID:2598031

  17. Human periodontal ligament stem cells repair mental nerve injury*

    Institute of Scientific and Technical Information of China (English)

    Bohan Li; Hun-Jong Jung; Soung-Min Kim; Myung-Jin Kim; Jeong Won Jahng; Jong-Ho Lee

    2013-01-01

    Human periodontal ligament stem cells are easily accessible and can differentiate into Schwann cells. We hypothesized that human periodontal ligament stem cells can be used as an alternative source for the autologous Schwann cells in promoting the regeneration of injured peripheral nerve. To validate this hypothesis, human periodontal ligament stem cells (1 × 106) were injected into the crush-injured left mental nerve in rats. Simultaneously, autologous Schwann cells (1 × 106) and PBS were also injected as controls. Real-time reverse transcriptase polymerase chain reaction showed that at 5 days after injection, mRNA expression of low affinity nerve growth factor receptor was sig-nificantaly increased in the left trigeminal ganglion of rats with mental nerve injury. Sensory tests, histomorphometric evaluation and retrograde labeling demonstrated that at 2 and 4 weeks after in-jection, sensory function was significantly improved, the numbers of retrograde labeled sensory neurons and myelinated axons were significantly increased, and human periodontal ligament stem cells and autologous Schwann cells exhibited similar therapeutic effects. These findings suggest that transplantation of human periodontal ligament stem cells show a potential value in repair of mental nerve injury.

  18. Glucose, other secretagogues, and nerve growth factor stimulate mitogen-activated protein kinase in the insulin-secreting beta-cell line, INS-1

    DEFF Research Database (Denmark)

    Frödin, M; Sekine, N; Roche, E;

    1995-01-01

    converge to activate 44-kDa mitogen-activated protein (MAP) kinase. Thus, glucose-induced insulin secretion was found to be associated with a small stimulatory effect on 44-kDa MAP kinase, which was synergistically enhanced by increased levels of intracellular cAMP and by the hormonal secretagogues...... glucagon-like peptide-1 and pituitary adenylate cyclase-activating polypeptide. Activation of 44-kDa MAP kinase by glucose was dependent on Ca2+ influx and may in part be mediated by MEK-1, a MAP kinase kinase. Stimulation of Ca2+ influx by KCl was in itself sufficient to activate 44-kDa MAP kinase and MEK......-1. Phorbol ester, an activator of protein kinase C, stimulated 44-kDa MAP kinase by both Ca(2+)-dependent and -independent pathways. Nerve growth factor, independently of changes in cytosolic Ca2+, efficiently stimulated 44-kDa MAP kinase without causing insulin release, indicating that activation...

  19. Variable Patterned Pudendal Nerve Stimuli Improves Reflex Bladder Activation

    OpenAIRE

    Bruns, Tim M.; Bhadra, Narendra; Gustafson, Kenneth J.

    2008-01-01

    We evaluated variable patterns of pudendal nerve (PN) stimuli for reflex bladder excitation. Reflex activation of the bladder has been demonstrated previously with 20–33 Hz continuous stimulation of PN afferents. Neuronal circuits accessed by afferent mediated pathways may respond better to physiological patterned stimuli than continuous stimulation. Unilateral PN nerve cuffs were placed in neurologically intact male cats. PN stimulation (0.5–100 Hz) was performed under isovolumetric conditio...

  20. Electrical stimulation of nerve cells using conductive nanofibrous scaffolds for nerve tissue engineering.

    Science.gov (United States)

    Ghasemi-Mobarakeh, Laleh; Prabhakaran, Molamma P; Morshed, Mohammad; Nasr-Esfahani, Mohammad Hossein; Ramakrishna, Seeram

    2009-11-01

    Fabrication of scaffolds with suitable chemical, mechanical, and electrical properties is critical for the success of nerve tissue engineering. Electrical stimulation was directly applied to electrospun conductive nanofibrous scaffolds to enhance the nerve regeneration process. In the present study, electrospun conductive nanofibers were prepared by mixing 10 and 15 wt% doped polyaniline (PANI) with poly (epsilon-caprolactone)/gelatin (PG) (70:30) solution (PANI/PG) by electrospinning. The fiber diameter, pore size, hydrophilicity, tensile properties, conductivity, Fourier transform infrared (FTIR), and X-ray photoelectron spectroscopy spectra of nanofibers were determined, and the in vitro biodegradability of the different nanofibrous scaffolds was also evaluated. Nanofibrous scaffolds containing 15% PANI was found to exhibit the most balanced properties to meet all the required specifications for electrical stimulation for its enhanced conductivity and is used for in vitro culture and electrical stimulation of nerve stem cells. 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay and scanning electron microscopy results showed that conductive nanofibrous scaffolds are suitable substrates for the attachment and proliferation of nerve stem cells. Electrical stimulation through conductive nanofibrous PANI/PG scaffolds showed enhanced cell proliferation and neurite outgrowth compared to the PANI/PG scaffolds that were not subjected to electrical stimulation.

  1. Growth-promoting activity of Hominis Placenta extract on regenerating sciatic nerve

    Institute of Scientific and Technical Information of China (English)

    Tae-beom SEO; Dong-hee KIM; Seung-kiel PARK; Deok-chun YANG; Uk NAMGUNG; In-sun HAN; Jin-hwan YOON; In-chan SEOL; Yun-sik KIM; Hyun-kyung JO; Joung-jo AN; Kwon-eui HONG; Young-bae SEO

    2006-01-01

    Aim: Extract of Hominis Placenta (HP) has been used in oriental medicine as an agent for improving physiological function. The present study was conducted to investigate whether HP treatment in an experimental sciatic nerve injury animal model produces growth-promoting effects on regenerating peripheral nerve fibers after injury. Methods: After HP was injected into a sciatic nerve injury site, changes in protein levels were analyzed in the regenerating nerve area by Western blotting and immunofluorescence staining analyses. For quantitative assessment of axonal regeneration, a retrograde tracing technique was used to identify the neuronal cell bodies corresponding to regenerating axons, and the extent of neurite outgrowth in cultured dorsal root ganglia (DRG) sensory neurons prepared from animals that had experienced a sciatic nerve crush injury 7 d before neuron collection was analyzed. Results: Induction levels of axonal growth-associated protein (GAP-43) in the injured sciatic nerves were elevated by HP treatment. HP treatment also upregulated cell division cycle 2 (Cdc2) protein levels in the distal stump of the injured sciatic nerve. Induced Cdc2 protein was detected in Schwann cells, suggesting that Cdc2 kinase activity may be involved in the growth-promoting activity of regenerating axons via Schwann cell proliferation. Cell body measurement by retrograde tracing indicated that HP treatment produced significant increases in regenerating motor axons. Finally, HP treatment of cultured DRG sensory neurons significantly increased neurite arborization and elongation.Conclusion: HP promotes the regeneration of injured sciatic axons by upregulating the synthesis of regeneration-related protein factors such as GAP-43 and Cdc2.

  2. Nerve Growth Factor in Cancer Cell Death and Survival

    International Nuclear Information System (INIS)

    One of the major challenges for cancer therapeutics is the resistance of many tumor cells to induction of cell death due to pro-survival signaling in the cancer cells. Here we review the growing literature which shows that neurotrophins contribute to pro-survival signaling in many different types of cancer. In particular, nerve growth factor, the archetypal neurotrophin, has been shown to play a role in tumorigenesis over the past decade. Nerve growth factor mediates its effects through its two cognate receptors, TrkA, a receptor tyrosine kinase and p75NTR, a member of the death receptor superfamily. Depending on the tumor origin, pro-survival signaling can be mediated by TrkA receptors or by p75NTR. For example, in breast cancer the aberrant expression of nerve growth factor stimulates proliferative signaling through TrkA and pro-survival signaling through p75NTR. This latter signaling through p75NTR promotes increased resistance to the induction of cell death by chemotherapeutic treatments. In contrast, in prostate cells the p75NTR mediates cell death and prevents metastasis. In prostate cancer, expression of this receptor is lost, which contributes to tumor progression by allowing cells to survive, proliferate and metastasize. This review focuses on our current knowledge of neurotrophin signaling in cancer, with a particular emphasis on nerve growth factor regulation of cell death and survival in cancer

  3. Preferential and comprehensive reconstitution of severely damaged sciatic nerve using murine skeletal muscle-derived multipotent stem cells.

    Directory of Open Access Journals (Sweden)

    Tetsuro Tamaki

    Full Text Available Loss of vital functions in the somatic motor and sensory nervous systems can be induced by severe peripheral nerve transection with a long gap following trauma. In such cases, autologous nerve grafts have been used as the gold standard, with the expectation of activation and proliferation of graft-concomitant Schwann cells associated with their paracrine effects. However, there are a limited number of suitable sites available for harvesting of nerve autografts due to the unavoidable sacrifice of other healthy functions. To overcome this problem, the potential of skeletal muscle-derived multipotent stem cells (Sk-MSCs was examined as a novel alternative cell source for peripheral nerve regeneration. Cultured/expanded Sk-MSCs were injected into severely crushed sciatic nerve corresponding to serious neurotmesis. After 4 weeks, engrafted Sk-MSCs preferentially differentiated into not only Schwann cells, but also perineurial/endoneurial cells, and formed myelin sheath and perineurium/endoneurium, encircling the regenerated axons. Increased vascular formation was also observed, leading to a favorable blood supply and waste product excretion. In addition, engrafted cells expressed key neurotrophic and nerve/vascular growth factor mRNAs; thus, endocrine/paracrine effects for the donor/recipient cells were also expected. Interestingly, skeletal myogenic capacity of expanded Sk-MSCs was clearly diminished in peripheral nerve niche. The same differentiation and tissue reconstitution capacity of Sk-MSCs was sufficiently exerted in the long nerve gap bridging the acellular conduit, which facilitated nerve regeneration/reconnection. These effects represent favorable functional recovery in Sk-MSC-treated mice, as demonstrated by good corduroy walking. We also demonstrated that these differentiation characteristics of the Sk-MSCs were comparable to native peripheral nerve-derived cells, whereas the therapeutic capacities were largely superior in Sk

  4. In vivo MRI monitoring nerve regeneration of acute peripheral nerve traction injury following mesenchymal stem cell transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Xiao-Hui, E-mail: duanxiaohui-128@163.com [Department of Radiology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, No. 107 Yanjiang Road West, Guangzhou 510120, Guangdong (China); Cheng, Li-Na, E-mail: kobe10716@163.com [Department of Radiology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, No. 107 Yanjiang Road West, Guangzhou 510120, Guangdong (China); Zhang, Fang, E-mail: xinxin110007@yahoo.com.cn [Department of Radiology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, No. 107 Yanjiang Road West, Guangzhou 510120, Guangdong (China); Liu, Jun, E-mail: docliujun@hotmail.com [Department of Neurology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, No. 107 Yanjiang Road West, Guangzhou 510120, Guangdong (China); Guo, Ruo-Mi, E-mail: guoruomi-521@163.com [Department of Radiology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, No. 107 Yanjiang Road West, Guangzhou 510120, Guangdong (China); Zhong, Xiao-Mei, E-mail: enough300@yahoo.com.cn [Department of Radiology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, No. 107 Yanjiang Road West, Guangzhou 510120, Guangdong (China); Wen, Xue-Hua, E-mail: xuehuasuqian@126.com [Department of Radiology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, No. 107 Yanjiang Road West, Guangzhou 510120, Guangdong (China); Shen, Jun, E-mail: junshenjun@hotmail.com [Department of Radiology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, No. 107 Yanjiang Road West, Guangzhou 510120, Guangdong (China)

    2012-09-15

    Objective: To assess the continuous process of nerve regeneration in acute peripheral nerve traction injury treated with mesenchymal stem cells (MSCs) transplantation using MRI. Materials and methods: 1 week after acute nerve traction injury was established in the sciatic nerve of 48 New Zealand white rabbits, 5 × 10{sup 5} MSCs and vehicle alone were grafted to the acutely distracted sciatic nerves each in 24 animals. Serial MRI and T1 and T2 measurements of the injured nerves were performed with a 1.5-T scanner and functional recovery was recorded over a 10-week follow-up period, with histological assessments performed at regular intervals. Results: Compared with vehicle control, nerves grafted with MSCs had better functional recovery and showed improved nerve regeneration, with a sustained increase of T1 and T2 values during the phase of regeneration. Conclusion: MRI could be used to monitor the enhanced nerve regeneration in acute peripheral nerve traction injury treated with MSC transplantation, reflected by a prolonged increase in T1 and T2 values of the injured nerves.

  5. Bone marrow-derived cells in the population of spinal microglia after peripheral nerve injury

    OpenAIRE

    Ryoichi Tashima; Satsuki Mikuriya; Daisuke Tomiyama; Miho Shiratori-Hayashi; Tomohiro Yamashita; Yuta Kohro; Hidetoshi Tozaki-Saitoh; Kazuhide Inoue; Makoto Tsuda

    2016-01-01

    Accumulating evidence indicates that peripheral nerve injury (PNI) activates spinal microglia that are necessary for neuropathic pain. Recent studies using bone marrow (BM) chimeric mice have reported that after PNI, circulating BM-derived cells infiltrate into the spinal cord and differentiate into microglia-like cells. This raises the possibility that the population of spinal microglia after PNI may be heterogeneous. However, the infiltration of BM cells in the spinal cord remains controver...

  6. Bridging long gap peripheral nerve injury using skeletal muscle-derived multipotent stem cells

    Institute of Scientific and Technical Information of China (English)

    Tetsuro Tamaki

    2014-01-01

    Long gap peripheral nerve injuries usually reulting in life-changing problems for patients. Skeletal muscle derived-multipotent stem cells (Sk-MSCs) can differentiate into Schwann and perineurial/endoneurial cells, vascular relating pericytes, and endothelial and smooth muscle cells in the damaged peripheral nerve niche. Application of the Sk-MSCs in the bridging conduit for repairing long nerve gap injury resulted favorable axonal regeneration, which showing supe-rior effects than gold standard therapy--healthy nerve autograft. This means that it does not need to sacriifce of healthy nerves or loss of related functions for repairing peripheral nerve injury.

  7. Human amniotic epithelial cell transplantation for the repair of injured brachial plexus nerve: evaluation of nerve viscoelastic properties

    Directory of Open Access Journals (Sweden)

    Hua Jin

    2015-01-01

    Full Text Available The transplantation of embryonic stem cells can effectively improve the creeping strength of nerves near an injury site in animals. Amniotic epithelial cells have similar biological properties as embryonic stem cells; therefore, we hypothesized that transplantation of amniotic epithelial cells can repair peripheral nerve injury and recover the creeping strength of the brachial plexus nerve. In the present study, a brachial plexus injury model was established in rabbits using the C 6 root avulsion method. A suspension of human amniotic epithelial cells was repeatedly injected over an area 4.0 mm lateral to the cephal and caudal ends of the C 6 brachial plexus injury site (1 × 10 6 cells/mL, 3 μL/injection, 25 injections immediately after the injury. The results showed that the decrease in stress and increase in strain at 7,200 seconds in the injured rabbit C 6 brachial plexus nerve were mitigated by the cell transplantation, restoring the viscoelastic stress relaxation and creep properties of the brachial plexus nerve. The forepaw functions were also significantly improved at 26 weeks after injury. These data indicate that transplantation of human amniotic epithelial cells can effectively restore the mechanical properties of the brachial plexus nerve after injury in rabbits and that viscoelasticity may be an important index for the evaluation of brachial plexus injury in animals.

  8. Human amniotic epithelial cell transplantation for the repair of injured brachial plexus nerve:evaluation of nerve viscoelastic properties

    Institute of Scientific and Technical Information of China (English)

    Hua Jin; Qi Yang; Feng Ji; Ya-jie Zhang; Yan Zhao; Min Luo

    2015-01-01

    The transplantation of embryonic stem cells can effectively improve the creeping strength of nerves near an injury site in animals. Amniotic epithelial cells have similar biological properties as em-bryonic stem cells; therefore, we hypothesized that transplantation of amniotic epithelial cells can repair peripheral nerve injury and recover the creeping strength of the brachial plexus nerve. In the present study, a brachial plexus injury model was established in rabbits using the C6root avulsion method. A suspension of human amniotic epithelial cells was repeatedly injected over an area 4.0 mm lateral to the cephal and caudal ends of the C6 brachial plexus injury site (1 × 106 cells/mL, 3μL/injection, 25 injections) immediately after the injury. The results showed that the decrease in stress and increase in strain at 7,200 seconds in the injured rabbit C6 brachial plexus nerve were mitigated by the cell transplantation, restoring the viscoelastic stress relaxation and creep properties of the brachial plexus nerve. The forepaw functions were also signiifcantly improved at 26 weeks after injury. These data indicate that transplantation of human amniotic epithelial cells can effec-tively restore the mechanical properties of the brachial plexus nerve after injury in rabbits and that viscoelasticity may be an important index for the evaluation of brachial plexus injury in animals.

  9. Transient brown adipocyte-like cells derive from peripheral nerve progenitors in response to bone morphogenetic protein 2.

    Science.gov (United States)

    Salisbury, Elizabeth A; Lazard, Zawaunyka W; Ubogu, Eroboghene E; Davis, Alan R; Olmsted-Davis, Elizabeth A

    2012-12-01

    Perineurial-associated brown adipocyte-like cells were rapidly generated during bone morphogenetic protein 2 (BMP2)-induced sciatic nerve remodeling in the mouse. Two days after intramuscular injection of transduced mouse fibroblast cells expressing BMP2 into wild-type mice, there was replication of beta-3 adrenergic receptor(+) (ADRB3(+)) cells within the sciatic nerve perineurium. Fluorescence-activated cell sorting and analysis of cells isolated from these nerves confirmed ADRB3(+) cell expansion and their expression of the neural migration marker HNK1. Similar analysis performed 4 days after BMP2 delivery revealed a significant decrease in ADRB3(+) cells from isolated sciatic nerves, with their concurrent appearance within the adjacent soft tissue, suggesting migration away from the nerve. These soft tissue-derived cells also expressed the brown adipose marker uncoupling protein 1 (UCP1). Quantification of ADRB3-specific RNA in total hind limb tissue revealed a 3-fold increase 2 days after delivery of BMP2, followed by a 70-fold increase in UCP1-specific RNA after 3 days. Expression levels then rapidly returned to baseline by 4 days. Interestingly, these ADRB3(+) UCP1(+) cells also expressed the neural guidance factor reelin. Reelin(+) cells demonstrated distinct patterns within the injected muscle, concentrated toward the area of BMP2 release. Blocking mast cell degranulation-induced nerve remodeling resulted in the complete abrogation of UCP1-specific RNA and protein expression within the hind limbs following BMP2 injection. The data collectively suggest that local BMP2 administration initiates a cascade of events leading to the expansion, migration, and differentiation of progenitors from the peripheral nerve perineurium to brown adipose-like cells in the mouse, a necessary prerequisite for associated nerve remodeling. PMID:23283549

  10. Skeletal muscle cell apoptosis following motornerve injury versus sensory nerve injury

    Institute of Scientific and Technical Information of China (English)

    Lei Zhao; Ruisheng Xu; Shenyang Jiang; Guangming Lü; Zhiqiang Yan; Junming Sun; Ling Wang; Ye Xue; Donglin Jiang

    2011-01-01

    Skeletal muscle atrophy inevitably occurs in denervated skeletal muscle, and cell apoptosis plays an important role in skeletal muscle atrophy and degeneration. The present study established rat models of simple nerve injury by transecting the ventral or dorsal spinal nerve root and observed rat skeletal muscle cell apoptosis following simple motor nerve injury versus simple sensory nerve injury. Following skeletal muscle denervation for 10 weeks, cell apoptosis was detected in skeletal muscle, which was accompanied by obvious changes in rat behavior and electrophysiological responses. In addition, changes in cross-sectional area and average gray-scale of motor endplates of the gastrocnemius muscle were analyzed following sciatic nerve injury and motor nerve injury.Cell nuclei in denervated skeletal muscle tissue were more densely arranged than in normal skeletal muscle tissue. Cell nuclei were most dense in the sciatic nerve injury group, followed by the motor nerve injury group and the sensory nerve injury group. Fas/Fast expression and the number of apoptotic cells increased in denervated skeletal muscle, and apoptosis-related changes were observed. These findings suggested that motor and sensory nerves provided trophic actions following skeletal muscle and motor nerve injury, resulting in a greater influence on skeletal muscle atrophy than sensory nerve injury. Therefore, reconstruction of motor nerves should be preferentially considered for treating denervation-induced skeletal muscle atrophy.

  11. Bridging sciatic nerve gap using tissue-engineered nerves constructed with neural tissue-committed stem cells derived from bone marrow

    Institute of Scientific and Technical Information of China (English)

    Zhiying Zhang; Congli Ren; Chuansen Zhang; Fang Liu; Liang Li

    2009-01-01

    BACKGROUND: Schwann cells are the most commonly used cells for tissue-engineered nerves. However, autologous Schwann cells are of limited use in a clinical context, and allogeneic Schwann cells induce immunological rejections. Cells that do not induce immunological rejections and that are relatively easy to acquire are urgently needed for transplantation.OBJECTIVE: To bridge sciatic nerve defects using tissue engineered nerves constructed with neural tissue-committed stem cells (NTCSCs) derived from bone marrow; to observe morphology and function of rat nerves following bridging; to determine the effect of autologous nerve transplantation, which serves as the gold standard for evaluating efficacy of tissue-engineered nerves.DESIGN, TIME AND SETTING: This randomized, controlled, animal experiment was performed in the Anatomical laboratory and Biomedical Institute of the Second Military Medical University of Chinese PLA between September 2004 and April 2006.MATERIALS: Five Sprague Dawley rats, aged 1 month and weighing 100-150 g, were used for cell culture. Sixty Sprague Dawiey rats aged 3 months and weighing 220-250 g, were used to establish neurological defect models. Nestin, neuron-specific enolase (NSE), glial fibrillary acidic protein (GFAP), and S-100 antibodies were provided by Santa Cruz Biotechnology, Inc., USA. Acellular nerve grafts were derived from dogs.METHODS: All rats, each with 1-cm gap created in the right sciatic nerve, were randomly assigned to three groups. Each group comprised 20 rats. Autograft nerve transplantation group: the severed 1-cm length nerve segment was reverted, but with the two ends exchanged; the proximal segment was sutured to the distal sciatic nerve stump and the distal segment to the proximal stump. Blank nerve scaffold transplantation group: a 1-cm length acellular nerve graft was used to bridge the sciatic nerve gap. NTCSC engineered nerve transplantation group: a 1-cm length acellular nerve graft, in which NTCSCs were

  12. Laryngeal Nerve Activity During Pulse Emission in the CF-FM Bat, Rhinolophus ferrumequinum. II. The Recurrent Laryngeal Nerve

    OpenAIRE

    Rübsamen, R.; Schuller, Gerd

    1981-01-01

    The activity of the recurrent laryngeal nerve (RLN) was recorded in the greater horseshoe bat,Rhinolophus ferrumequinum. Respiration, vocalization and nerve discharges were monitored while vocalizations were elicted by stimulation of the central gray matter. This stimulation evoked either expiration or expiration plus vocalization depending on the stimulus strength. When vocalization occurred it always took place during expiration. Recordings from the RLN during respiration showed activity...

  13. Effects of leptin on sympathetic nerve activity in conscious mice

    OpenAIRE

    Morgan, Donald A.; Despas, Fabien; Rahmouni, Kamal

    2015-01-01

    The adipocyte-derived hormone, leptin, has emerged as an important regulator of regional sympathetic nerve activity (SNA) with pathophysiological implications in obesity. Genetically engineered mice are useful to understand the molecular pathways underlying the SNA responses evoked by leptin. However, so far the effect of leptin on direct SNA in mice has been studied under general anesthesia. Here, we examined the sympathetic responses evoked by leptin in conscious mice. Mice were instrumente...

  14. Human amniotic epithelial cells express specific markers of nerve cells and migrate along the nerve fibers in the corpus callosum

    Institute of Scientific and Technical Information of China (English)

    Zhiyuan Wu; Guozhen Hui; Yi Lu; Tianjin Liu; Qin Huang; Lihe Guo

    2012-01-01

    Human amniotic epithelial cells were isolated from a piece of fresh amnion. Using immunocytochemical methods, we investigated the expression of neuronal phenotypes (microtubule-associated protein-2, glial fibrillary acidic protein and nestin) in human amniotic epithelial cells. The conditioned medium of human amniotic epithelial cells promoted the growth and proliferation of rat glial cells cultured in vitro, and this effect was dose-dependent. Human amniotic epithelial cells were further transplanted into the corpus striatum of healthy adult rats and the grafted cells could integrate with the host and migrate 1-2 mm along the nerve fibers in corpus callosum. Our experimental findings indicate that human amniotic epithelial cells may be a new kind of seed cells for use in neurograft.

  15. Perineural alpha(2A)-adrenoceptor activation inhibits spinal cord neuroplasticity and tactile allodynia after nerve injury.

    OpenAIRE

    Lavand'homme, Patricia; Ma, Weiya; Kock, Marc De; Eisenach, James C.

    2002-01-01

    BACKGROUND: Nerve injury in animals increases alpha(2)-adrenoceptor expression in dorsal root ganglion cells and results in novel excitatory responses to their activation, perhaps leading to the phenomenon of sympathetically maintained pain. In contrast to this notion, peripheral alpha(2)-adrenoceptor stimulation fails to induce pain in patients with chronic pain. We hypothesized that alpha(2) adrenoceptors at the site of nerve injury play an inhibitory, not excitatory role. METHODS: Partial ...

  16. Advances in recording scattered light changes in crustacean nerve with electrical activation

    Energy Technology Data Exchange (ETDEWEB)

    Carter, K. M. (Kathleen M.); Rector, D. M. (David M.); Martinez, A. T. (Anne T.); Guerra, F. M. (Francisco M.); George, J. S. (John S.)

    2002-01-01

    We investigated optical changes associated with crustacean nerve stimulation using birefringent and large angle scattered light. Improved detection schemes disclosed high temporal structure of the optical signals and allowed further investigations of biophysical mechanisms responsible for such changes. Most studies of physiological activity in neuronal tissue use techniques that measure the electrical behavior or ionic permeability of the nerve, such as voltage or ion sensitive dyes injected into cells, or invasive electric recording apparatus. While these techniques provide high resolution, they are detrimental to tissue and do not easily lend themselves to clinical applications in humans. Electrical and chemical components of neural excitation evoke physical responses observed through changes in scattered and absorbed light. This method is suited for in-vivo applications. Intrinsic optical changes have shown themselves to be multifaceted in nature and point to several different physiological processes that occur with different time courses during neural excitation. Fast changes occur concomitantly with electrical events, and slow changes parallel metabolic events including changes in blood flow and oxygenation. Previous experiments with isolated crustacean nerves have been used to study the biophysical mechanisms of fast optical changes. However, they have been confounded by multiple superimposed action potentials which make it difficult to discriminate the temporal signatures of individual optical responses. Often many averages were needed to adequately resolve the signal. More recently, optical signals have been observed in single trials. Initially large angle scattering measurements were used to record these events with much of the signal coming from cellular swelling associated with water influx during activation. By exploiting the birefringent properties derived from the molecular stiucture of nerve membranes, signals appear larger with a greater contrast

  17. Contribution of spinal glia activation to mechanical hyperalgesia induced by spared nerve injury in rats

    Institute of Scientific and Technical Information of China (English)

    FENG Si-zhe; WEI Xue-zhong; ZHANG Xiang

    2004-01-01

    Objective: To investigate the role of spinal glial cells activation in neuropathic pain in a recently developed spared nerve injury (SNI) animal model by Decosterd and Woolf. Methods: A lesion was made to two of the three terminal branches of the sciatic nerve of rats (tibial and common peroneal nerves) leaving the sural nerve intact. Continuous intrathecai administration of propentofyliine, a glial modulating agent, 1 d before and 5 d after operation, was performed to disrupt spinal cord glia function. The vehicle was intrathecally administrated as control. The paw withdrawal threshold to mechanical stimulation (paw withdrawal mechaical threshold PWMT), body mass and motor function were determined pre- and post-surgery. Results: It produced a prolonged mechanical allodynia in the medial and lateral part of the ipsilateral hind paw in SNL models. The treatment with propentofylline significantly prevented the development of mechanical allodynia located in either medial or lateral plantar surface. Rats in two groups showed normal motor function and body weight increase. Conclusion:SNI model can be applied as a useful method with little variance in searching the mechanism of neuropathic pain. These study suggest that spinal glia activation may contribute to mechanical allodynia induced by SNI.

  18. Role of sympathetic nerve activity in the process of fainting

    Directory of Open Access Journals (Sweden)

    Satoshi eIwase

    2014-09-01

    Full Text Available Syncope is defined as a transient loss of consciousness and postural tone, characterized by rapid onset, short duration, and spontaneous recovery, and the process of syncope progression will be described with two types of sympathetic change. Simultaneous recordings of microneurographically recorded MSNA and continuous and noninvasive blood pressure measurement have disclose what is going on in the course of progression of the syncope. Vasovagal or neurally mediated syncope, three stages are identified in the course of syncope onset, oscillation, imbalance, and catastrophe phases. The vasovagal syncope is characterized by the sympathoexcitation, followed by vagal overcome via the Bezold-Jarisch reflex. Orthostatic syncope is caused by the response failure or lack of sympathetic nerve activity toward the orthostatic challenge followed by the fluid shift, and subsequent cerebral low perfusion. Four causes are considered for the compensatory failure, which triggers the orthostatic syncope; hypovolemia, increased pooling in the lower body, failure to activate the sympathetic activity, and failure of vasoconstriction against sympathetic vasoconstrictive stimulation. Many pathophysiological conditions were described in the viewpoint of 1 exaggerated sympathoexcitation and 2 failure to activate the sympathetic nerve. We conclude that the sympathetic nervous system can control the cardiovascular function, and its failure resulted syncope, however, responses of the system by microneurographically recorded MSNA would determine the pathophysiology of the onset and progression of syncope, explaining the treatment effect that could be achieved by the analysis of this mechanism.

  19. Enhancement of Peripheral Nerve Regrowth by the Purine Nucleoside Analog and Cell Cycle Inhibitor, Roscovitine

    Science.gov (United States)

    Law, Vincent; Dong, Sophie; Rosales, Jesusa L.; Jeong, Myung-Yung; Zochodne, Douglas; Lee, Ki-Young

    2016-01-01

    Peripheral nerve regeneration is a slow process that can be associated with limited outcomes and thus a search for novel and effective therapy for peripheral nerve injury and disease is crucial. Here, we found that roscovitine, a synthetic purine nucleoside analog, enhances neurite outgrowth in neuronal-like PC12 cells. Furthermore, ex vivo analysis of pre-injured adult rat dorsal root ganglion (DRG) neurons showed that roscovitine enhances neurite regrowth in these cells. Likewise, in vivo transected sciatic nerves in rats locally perfused with roscovitine had augmented repopulation of new myelinated axons beyond the transection zone. By mass spectrometry, we found that roscovitine interacts with tubulin and actin. It interacts directly with tubulin and causes a dose-dependent induction of tubulin polymerization as well as enhances Guanosine-5′-triphosphate (GTP)-dependent tubulin polymerization. Conversely, roscovitine interacts indirectly with actin and counteracts the inhibitory effect of cyclin-dependent kinases 5 (Cdk5) on Actin-Related Proteins 2/3 (Arp2/3)-dependent actin polymerization, and thus, causes actin polymerization. Moreover, in the presence of neurotrophic factors such as nerve growth factor (NGF), roscovitine-enhanced neurite outgrowth is mediated by increased activation of the extracellular signal-regulated kinases 1/2 (ERK1/2) and p38 mitogen-activated protein kinase (MAPK) pathways. Since microtubule and F-actin dynamics are critical for axonal regrowth, the ability of roscovitine to activate the ERK1/2 and p38 MAPK pathways and support polymerization of tubulin and actin indicate a major role for this purine nucleoside analog in the promotion of axonal regeneration. Together, our findings demonstrate a therapeutic potential for the purine nucleoside analog, roscovitine, in peripheral nerve injury.

  20. JNK3 involvement in nerve cell apoptosis and neurofunctional recovery after traumatic brain injury☆

    Institute of Scientific and Technical Information of China (English)

    Jiang Long; Li Cai; Jintao Li; Lei Zhang; Haiyang Yang; Tinghua Wang

    2013-01-01

    Increasing evidence has revealed that the activation of the JNK pathway participates in apoptosis of nerve cells and neurological function recovery after traumatic brain injury. However, which genes in the JNK family are activated and their role in traumatic brain injury remain unclear. Therefore, in this study, in situ end labeling, reverse transcription-PCR and neurological function assessment were adopted to investigate the alteration of JNK1, JNK2 and JNK3 gene expression in cerebral injured rats, and their role in cell apoptosis and neurological function restoration. Results showed that JNK3 expression significantly decreased at 1 and 6 hours and 1 and 7 days post injury, but that JNK1 and JNK2 expression remained unchanged. In addition, the number of apoptotic nerve cells surrounding the injured cerebral cortex gradually reduced over time post injury. The Neurological Severity Scores gradually decreased over 1, 3, 5, 14 and 28 days post injury. These findings suggested that JNK3 expression was downregulated at early stages of brain injury, which may be associated with apoptosis of nerve cells. Downregulation of JNK3 expression may promote the recovery of neurological function following traumatic brain injury.

  1. Activated eosinophils in association with enteric nerves in inflammatory bowel disease.

    Directory of Open Access Journals (Sweden)

    Claire M Smyth

    Full Text Available Enteric neural dysfunction leads to increased mucous production and dysmotility in inflammatory bowel disease (IBD. Prior studies have shown that tissue eosinophilia is related to disease activity. We hypothesized that interactions between eosinophils and nerves contribute to neural dysfunction in IBD. Tissue from patients with intractable IBD, endoscopic biopsies from patients with steroid responsive IBD, both when active and quiescent, and control tissue were studied. Immunohistochemical studies showed that eosinophils localize to nerves in the mucosal layer of patients with Crohn's disease (CD (p<0.001 and ulcerative colitis (UC, (p<0.01. Eosinophils localized to substance P and choline acetyltransferase (ChAT immunostained nerves. Real time PCR of laser capture micro-dissected enteric ganglia demonstrated Intercellular Adhesion Molecule 1 (ICAM-1 mRNA was increased 7-fold in UC (n = 4, (p = 0.03, and 10-fold in CD (n = 3, (p = 0.05. Compared with controls, eotaxin-3 (CCL-26 mRNA was increased 9-fold in UC (p = 0.04 and 15-fold in CD (p = 0.06. Eosinophil numbers correlated with disease activity, while deposition of major basic protein (MBP and eosinophil Transforming Growth Factor β-1 (TGFβ-1 expression were seen in therapeutically responsive disease. These data indicate a significant localization of eosinophils to nerves in IBD, mediated through neurally expressed ICAM-1 and eotaxin-3. This cell/neural interaction may influence the function of nerves and contribute to symptoms in IBD.

  2. Retinal ganglion cell survival and axon regeneration in WldS transgenic rats after optic nerve crush and lens injury

    Directory of Open Access Journals (Sweden)

    Lorber Barbara

    2012-06-01

    Full Text Available Abstract Background We have previously shown that the slow Wallerian degeneration mutation, whilst delaying axonal degeneration after optic nerve crush, does not protect retinal ganglion cell (RGC bodies in adult rats. To test the effects of a combination approach protecting both axons and cell bodies we performed combined optic nerve crush and lens injury, which results in both enhanced RGC survival as well as axon regeneration past the lesion site in wildtype animals. Results As previously reported we found that the WldS mutation does not protect RGC bodies after optic nerve crush alone. Surprisingly, we found that WldS transgenic rats did not exhibit the enhanced RGC survival response after combined optic nerve crush and lens injury that was observed in wildtype rats. RGC axon regeneration past the optic nerve lesion site was, however, similar in WldS and wildtypes. Furthermore, activation of retinal glia, previously shown to be associated with enhanced RGC survival and axon regeneration after optic nerve crush and lens injury, was unaffected in WldS transgenic rats. Conclusions RGC axon regeneration is similar between WldS transgenic and wildtype rats, but WldS transgenic rats do not exhibit enhanced RGC survival after combined optic nerve crush and lens injury suggesting that the neuroprotective effects of lens injury on RGC survival may be limited by the WldS protein.

  3. In vitro evaluation of cell-seeded chitosan films for peripheral nerve tissue engineering

    OpenAIRE

    Wrobel, Sandra; Serra, Sofia Cristina; Samy, S. M.; Sousa, Nuno; Heimann, Claudia; Barwig, Christina; Grothe, Claudia; Salgado, A. J.; Talini, Kirsten Haastert

    2014-01-01

    Natural biomaterials have attracted an increasing interest in the field of tissue-engineered nerve grafts, representing a possible alternative to autologous nerve transplantation. With the prospect of developing a novel entubulation strategy for transected nerves with cell-seeded chitosan films, we examined the biocompatibility of such films in vitro. Different types of rat Schwann cells (SCs)—immortalized, neonatal, and adult—as well as rat bone-marrow-derived mesenchymal stromal cells (BMSC...

  4. High-resolution measurement of electrically-evoked vagus nerve activity in the anesthetized dog

    Science.gov (United States)

    Yoo, Paul B.; Lubock, Nathan B.; Hincapie, Juan G.; Ruble, Stephen B.; Hamann, Jason J.; Grill, Warren M.

    2013-04-01

    Objective. Not fully understanding the type of axons activated during vagus nerve stimulation (VNS) is one of several factors that limit the clinical efficacy of VNS therapies. The main goal of this study was to characterize the electrical recruitment of both myelinated and unmyelinated fibers within the cervical vagus nerve. Approach. In anesthetized dogs, recording nerve cuff electrodes were implanted on the vagus nerve following surgical excision of the epineurium. Both the vagal electroneurogram (ENG) and laryngeal muscle activity were recorded in response to stimulation of the right vagus nerve. Main results. Desheathing the nerve significantly increased the signal-to-noise ratio of the ENG by 1.2 to 9.9 dB, depending on the nerve fiber type. Repeated VNS following nerve transection or neuromuscular block (1) enabled the characterization of A-fibers, two sub-types of B-fibers, and unmyelinated C-fibers, (2) confirmed the absence of stimulation-evoked reflex compound nerve action potentials in both the ipsilateral and contralateral vagus nerves, and (3) provided evidence of stimulus spillover into muscle tissue surrounding the stimulating electrode. Significance. Given the anatomical similarities between the canine and human vagus nerves, the results of this study provide a template for better understanding the nerve fiber recruitment patterns associated with VNS therapies.

  5. Nerve growth factor promotes in vitro proliferation of neural stem cells from tree shrews

    Institute of Scientific and Technical Information of China (English)

    Liu-lin Xiong; Zhi-wei Chen; Ting-hua Wang

    2016-01-01

    Neural stem cells promote neuronal regeneration and repair of brain tissue after injury, but have limited resources and proliferative ability in vivo. We hypothesized that nerve growth factor would promotein vitro proliferation of neural stem cells derived from the tree shrews, a primate-like mammal that has been proposed as an alternative to primates in biomedical translational research. We cultured neural stem cells from the hippocampus of tree shrews at embryonic day 38, and added nerve growth factor (100 μg/L) to the culture medium. Neural stem cells from the hippocampus of tree shrews cultured without nerve growth factor were used as controls. After 3 days, lfuorescence mi-croscopy after DAPI and nestin staining revealed that the number of neurospheres and DAPI/nestin-positive cells was markedly greater in the nerve growth factor-treated cells than in control cells. These ifndings demonstrate that nerve growth factor promotes the proliferation of neural stem cells derived from tree shrews.

  6. Elevated intracranial pressure causes optic nerve and retinal ganglion cell degeneration in mice.

    Science.gov (United States)

    Nusbaum, Derek M; Wu, Samuel M; Frankfort, Benjamin J

    2015-07-01

    The purpose of this study was to develop a novel experimental system for the modulation and measurement of intracranial pressure (ICP), and to use this system to assess the impact of elevated ICP on the optic nerve and retinal ganglion cells (RGCs) in CD1 mice. This system involved surgical implantation of an infusion cannula and a radiowave based pressure monitoring probe through the skull and into the subarachnoid space. The infusion cannula was used to increase ICP, which was measured by the probe and transmitted to a nearby receiver. The system provided robust and consistent ICP waveforms, was well tolerated, and was stable over time. ICP was elevated to approximately 30 mmHg for one week, after which we assessed changes in optic nerve structure with transmission electron microscopy in cross section and RGC numbers with antibody staining in retinal flat mounts. ICP elevation resulted in optic nerve axonal loss and disorganization, as well as RGC soma loss. We conclude that the controlled manipulation of ICP in active, awake mice is possible, despite their small size. Furthermore, ICP elevation results in visual system phenotypes of optic nerve and RGC degeneration, suggesting that this model can be used to study the impact of ICP on the visual system. Potentially, this model can also be used to study the relationship between ICP and IOP, as well diseases impacted by ICP variation such as glaucoma, idiopathic intracranial hypertension, and the spaceflight-related visual impairment intracranial pressure syndrome. PMID:25912998

  7. Construction of nerve guide conduits from cellulose/soy protein composite membranes combined with Schwann cells and pyrroloquinoline quinone for the repair of peripheral nerve defect

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Lihua [Department of Biomedical Engineering, School of Basic Medical Sciences, Wuhan University, Wuhan 430071 (China); Center of Molecular Medicine, School of Medicine, Hubei University of Arts and Sciences, Xiangyang 441053 (China); Gan, Li; Liu, Yongming; Tian, Weiqun; Tong, Zan [Department of Biomedical Engineering, School of Basic Medical Sciences, Wuhan University, Wuhan 430071 (China); Wang, Xiong; Huselstein, Celine [Ingénierie Moléculaire et Physiopathologie Articulaire (IMoPA), UMR 7365 CNRS – Université de Lorraine, Biopôle, 54500 Vandoeuvre-lès-Nancy (France); Chen, Yun, E-mail: yunchen@whu.edu.cn [Department of Biomedical Engineering, School of Basic Medical Sciences, Wuhan University, Wuhan 430071 (China)

    2015-02-20

    Regeneration and functional reconstruction of peripheral nerve defects remained a significant clinical challenge. Nerve guide conduits, with seed cells or neurotrophic factors (NTFs), had been widely used to improve the repair and regeneration of injured peripheral nerve. Pyrroloquinoline quinone (PQQ) was an antioxidant that can stimulate nerve growth factors (NGFs) synthesis and accelerate the Schwann cells (SCs) proliferation and growth. In present study, three kinds of nerve guide conduits were constructed: one from cellulose/SPI hollow tube (CSC), another from CSC combined with SCs (CSSC), and the third one from CSSC combined with PQQ (CSSPC), respectively. And then they were applied to bridge and repair the sciatic nerve defect in rats, using autograft as control. Effects of different nerve guide conduits on the nerve regeneration were comparatively evaluated by general analysis, sciatic function index (SFI) and histological analysis (HE and TEM). Newly-formed regenerative nerve fibers were observed and running through the transparent nerve guide conduits 12 weeks after surgery. SFI results indicated that the reconstruction of motor function in CSSPC group was better than that in CSSC and CSC groups. HE images from the cross-sections and longitudinal-sections of the harvested regenerative nerve indicated that regenerative nerve fibers had been formed and accompanied with new blood vessels and matrix materials in the conduits. TEM images also showed that lots of fresh myelinated and non-myelinated nerve fibers had been formed. Parts of vacuolar, swollen and abnormal axons occurred in CSC and CSSC groups, while the vacuolization and swell of axons was the least serious in CSSPC group. These results indicated that CSSPC group had the most ability to repair and reconstruct the nerve structure and functions due to the comprehensive contributions from hollow CSC tube, SCs and PQQ. As a result, the CSSPC may have the potential for the applications as nerve guide

  8. [Antifibrillatory activity of dipeptide antagonist of nerve growth factor].

    Science.gov (United States)

    Kryzhanovskiĭ, S A; Stoliarchuk, V N; Vititnova, M B; Tsorin, I B; Pekel'dina, E S; Gudasheva, T A

    2012-01-01

    In experiments on anesthetized rats were assessed antifibrillatoty action of dipeptide GK-1. This compound is the fragment of fourth loop of nerve growth factor (NGF) and manifests antagonistic activity in respect to TrkA receptor, that specified for NGF. It is shown that this compound is able to significantly increase the threshold of electrical fibrillation of the heart and its effectiveness is not inferior to the reference antiarrhythmics I and III class on Vaughan Williams classification. However, unlike the latter, antifibrillatory action of dipeptide GK-1 was delayed and realized within 40-60 minutes after its administration. It is discussed possible mechanisms underlying antifibrillatory action of dipeptide GK-1, that, to some extent, may be associated with its ability to change the reactivity of beta-adrenergic structures of the heart.

  9. Protection of Acanthopanax Senticosus Saponin on Free Radical Injury Induced Aging of Nerve Cell

    Institute of Scientific and Technical Information of China (English)

    潘永进; 顾永健; 顾小苏

    2002-01-01

    Objective: To study the effect of Acanthopanax senticosus saponin (ASS) on free radical injury induced neuron aging. Methods: On day 7 of fetal mice, cortical neuron primary passage cultures were divided into the normal control group, model group and ASS groups. The model group using free radical (FeSO4 plus H2O2) injury mode prepared in vivo cultured ICR mice cortical neuron aging model; ASS groups: 24 hrs before and after treated with H2O2 and FeSO4, different concentration of ASS was added, according to biochemical parameters such as lactate dehydrogenase (LDH), superoxide dismutase (SOD) and malondialdehyde (MDA) etc. and histomorphologic change to observe the protection of ASS on aging neurons. Results: The LDH, SOD, MDA of the model group were compared with the normal group, P<0.01; ASS groups added 1.25 mg/100 ml, 2.5 mg/100 ml, 5 mg/100 ml concentration of ASS, their LDH, SOD, MDA compared with the model group P<0.05-0.01, the difference was significant. In medicated groups the SOD activity of oxidization injured nerve cells obviously elevated, LDH activity and MDA content apparently lowered. Microscope and scanning electron microscopic observation showed that supplemented with ASS to protect the nerve cell injury abated, part of the cellular structure tended to normalize. Conclusion: ASS could act against free radical toxic effect, increase the anti-oxidase activity, strengthen the protection of neuron cells. It is assumed that the effect against nerve cell aging was possibly through scavenging oxygen free radical, strengthening the stability of cell membrane, thus delaying the development of aging.

  10. Innexin gap junctions in nerve cells coordinate spontaneous contractile behavior in Hydra polyps

    KAUST Repository

    Takaku, Yasuharu

    2014-01-07

    Nerve cells and spontaneous coordinated behavior first appeared near the base of animal evolution in the common ancestor of cnidarians and bilaterians. Experiments on the cnidarian Hydra have demonstrated that nerve cells are essential for this behavior, although nerve cells in Hydra are organized in a diffuse network and do not form ganglia. Here we show that the gap junction protein innexin-2 is expressed in a small group of nerve cells in the lower body column of Hydra and that an anti-innexin-2 antibody binds to gap junctions in the same region. Treatment of live animals with innexin-2 antibody eliminates gap junction staining and reduces spontaneous body column contractions. We conclude that a small subset of nerve cells, connected by gap junctions and capable of synchronous firing, act as a pacemaker to coordinate the contraction of the body column in the absence of ganglia.

  11. Expression of adenovirus-mediated neurotrophin-3 gene in Schwann cells of sciatic nerve in rats

    Institute of Scientific and Technical Information of China (English)

    朱锦宇; 黄耀添; 朱庆生; 吕荣

    2003-01-01

    Objective: To investigate the expression of neurotrophin-3 (NT-3) gene in Schwann cells of rat sciatic nerve introduced by an adenovirus vector in vivo. Methods: A recombinant adenovirus vector for NT-3 (Ad-NT-3) was propagated in 293 packaging cells and titered with tissue culture infectious dose50 (TCID50). Ad-NT-3 was injected directly into the rat sciatic nerve after transection and immediate repair. Immunohistochemical staining was employed to determine the expression of NT-3 in Schwann cells in rat sciatic nerve and the expressive intensity of the tissue slices of the sciatic nerve was measured with LEICA M550 image analysis system. Results: On the 2nd day after injection of Ad-NT-3, positive stain in the Schwann cells was apparent in the vicinity of anastomosis. NT-3 expression increased significantly on the 7th day (P0.05). Compared with the 2nd day group, the 14th and 28th day groups still maintained a relatively high level of NT-3 (P<0.01). Intact and repaired nerves, which were injected with adenovirus encoding LacZ genes (Ad-LacZ) or physiological saline served as controls, showed no NT-3-positive Schwann cells. Conclusions: An adenovirus vector can be used to induce efficiently the expression of NT-3 gene in Schwann cells of rat peripheral nerves following nerve injury and repair, which suggests that neurotrophic factors can be introduced into Schwann cells with an adenovirus vector to promote peripheral nerve regeneration.

  12. A rapid and versatile method for the isolation, purification and cryogenic storage of Schwann cells from adult rodent nerves.

    Science.gov (United States)

    Andersen, Natalia D; Srinivas, Shruthi; Piñero, Gonzalo; Monje, Paula V

    2016-08-23

    We herein developed a protocol for the rapid procurement of adult nerve-derived Schwann cells (SCs) that was optimized to implement an immediate enzymatic dissociation of fresh nerve tissue while maintaining high cell viability, improving yields and minimizing fibroblast and myelin contamination. This protocol introduces: (1) an efficient method for enzymatic cell release immediately after removal of the epineurium and extensive teasing of the nerve fibers; (2) an adaptable drop-plating method for selective cell attachment, removal of myelin debris, and expansion of the initial SC population in chemically defined medium; (3) a magnetic-activated cell sorting purification protocol for rapid and effective fibroblast elimination; and (4) an optional step of cryopreservation for the storage of the excess of cells. Highly proliferative SC cultures devoid of myelin and fibroblast growth were obtained within three days of nerve processing. Characterization of the initial, expanded, and cryopreserved cell products confirmed maintenance of SC identity, viability and growth rates throughout the process. Most importantly, SCs retained their sensitivity to mitogens and potential for differentiation even after cryopreservation. To conclude, this easy-to-implement and clinically relevant protocol allows for the preparation of expandable homogeneous SC cultures while minimizing time, manipulation of the cells, and exposure to culture variables.

  13. A rapid and versatile method for the isolation, purification and cryogenic storage of Schwann cells from adult rodent nerves

    Science.gov (United States)

    Andersen, Natalia D.; Srinivas, Shruthi; Piñero, Gonzalo; Monje, Paula V.

    2016-01-01

    We herein developed a protocol for the rapid procurement of adult nerve-derived Schwann cells (SCs) that was optimized to implement an immediate enzymatic dissociation of fresh nerve tissue while maintaining high cell viability, improving yields and minimizing fibroblast and myelin contamination. This protocol introduces: (1) an efficient method for enzymatic cell release immediately after removal of the epineurium and extensive teasing of the nerve fibers; (2) an adaptable drop-plating method for selective cell attachment, removal of myelin debris, and expansion of the initial SC population in chemically defined medium; (3) a magnetic-activated cell sorting purification protocol for rapid and effective fibroblast elimination; and (4) an optional step of cryopreservation for the storage of the excess of cells. Highly proliferative SC cultures devoid of myelin and fibroblast growth were obtained within three days of nerve processing. Characterization of the initial, expanded, and cryopreserved cell products confirmed maintenance of SC identity, viability and growth rates throughout the process. Most importantly, SCs retained their sensitivity to mitogens and potential for differentiation even after cryopreservation. To conclude, this easy-to-implement and clinically relevant protocol allows for the preparation of expandable homogeneous SC cultures while minimizing time, manipulation of the cells, and exposure to culture variables. PMID:27549422

  14. Laser-activated protein solder for peripheral nerve repair

    Science.gov (United States)

    Trickett, Rodney I.; Lauto, Antonio; Dawes, Judith M.; Owen, Earl R.

    1995-05-01

    A 100 micrometers core optical fiber-coupled 75 mW diode laser operating at a wavelength of 800 nm has been used in conjunction with a protein solder to stripe weld severed rat tibial nerves, reducing the long operating time required for microsurgical nerve repair. Welding is produced by selective laser denaturation of the albumin based solder which contains the dye indocyanine green. Operating time for laser soldering was 10 +/- 5 min. (n equals 20) compared to 23 +/- 9 min. (n equals 10) for microsuturing. The laser solder technique resulted in patent welds with a tensile strength of 15 +/- 5 g, while microsutured nerves had a tensile strength of 40 +/- 10 g. Histopathology of the laser soldered nerves, conducted immediately after surgery, displayed solder adhesion to the outer membrane with minimal damage to the inner axons of the nerves. An in vivo study is under way comparing laser solder repaired tibial nerves to conventional microsuture repair. At the time of submission 15 laser soldered nerves and 7 sutured nerves were characterized at 3 months and showed successful regeneration with compound muscle action potentials of 27 +/- 8 mV and 29 +/- 8 mW respectively. A faster, less damaging and long lasting laser based anastomotic technique is presented.

  15. Injury-induced activation of ERK 1/2 in the sciatic nerve of healthy and diabetic rats.

    Science.gov (United States)

    Stenberg, Lena; Kanje, Martin; Mårtensson, Lisa; Dahlin, Lars B

    2011-01-26

    Phosphorylation of extracellular-signal-regulated kinase 1/2 (p-ERK 1/2) was investigated by immunohistochemistry at 30 min, 1 h, and 48 h after nerve transection in the sciatic nerve of healthy and diabetic [streptozotocin (STZ)-induced diabetes mellitus and BioBreeding (BB; i.e. DR.lyp/lyp or BBDP)] rats. Transection injury increased the intensity of p-ERK 1/2 in nerve stumps at all time points. Staining was confined to Schwann cells with occasional faint staining in single axons. In diabetic rats, a lower intensity of p-ERK 1/2 was found at 1 and 48 h in the distal and proximal nerve stumps compared with healthy rats. STZ-induced diabetic rats were not different from BB rats. p-ERK 1/2 is activated differentially in Schwann cells after nerve injury in diabetic rats, whereas activation in STZ-induced diabetic rats did not differ from BB rats.

  16. Bone marrow-derived cells in the population of spinal microglia after peripheral nerve injury.

    Science.gov (United States)

    Tashima, Ryoichi; Mikuriya, Satsuki; Tomiyama, Daisuke; Shiratori-Hayashi, Miho; Yamashita, Tomohiro; Kohro, Yuta; Tozaki-Saitoh, Hidetoshi; Inoue, Kazuhide; Tsuda, Makoto

    2016-01-01

    Accumulating evidence indicates that peripheral nerve injury (PNI) activates spinal microglia that are necessary for neuropathic pain. Recent studies using bone marrow (BM) chimeric mice have reported that after PNI, circulating BM-derived cells infiltrate into the spinal cord and differentiate into microglia-like cells. This raises the possibility that the population of spinal microglia after PNI may be heterogeneous. However, the infiltration of BM cells in the spinal cord remains controversial because of experimental adverse effects of strong irradiation used for generating BM chimeric mice. In this study, we evaluated the PNI-induced spinal infiltration of BM-derived cells not only by irradiation-induced myeloablation with various conditioning regimens, but also by parabiosis and mice with genetically labelled microglia, models without irradiation and BM transplantation. Results obtained from these independent approaches provide compelling evidence indicating little contribution of circulating BM-derived cells to the population of spinal microglia after PNI. PMID:27005516

  17. Repair of peripheral nerve defects with chemically extracted acellular nerve allografts loaded with neurotrophic factors-transfected bone marrow mesenchymal stem cells

    Institute of Scientific and Technical Information of China (English)

    Yan-ru Zhang; Ka Ka; Ge-chen Zhang; Hui Zhang; Yan Shang; Guo-qiang Zhao; Wen-hua Huang

    2015-01-01

    Chemically extracted acellular nerve allografts loaded with brain-derived neurotrophic fac-tor-transfected or ciliary neurotrophic factor-transfected bone marrow mesenchymal stem cells have been shown to repair sciatic nerve injury better than chemically extracted acellular nerve allografts alone, or chemically extracted acellular nerve allografts loaded with bone marrow mesenchymal stem cells. We hypothesized that these allografts compounded with both brain-derived neurotrophic factor- and ciliary neurotrophic factor-transfected bone marrow mesenchymal stem cells may demonstrate even better effects in the repair of peripheral nerve injury. We cultured bone marrow mesenchymal stem cells expressing brain-derived neuro-trophic factor and/or ciliary neurotrophic factor and used them to treat sciatic nerve injury in rats. We observed an increase in sciatic functional index, triceps wet weight recovery rate, myelin thickness, number of myelinated nerve ifbers, amplitude of motor-evoked potentials and nerve conduction velocity, and a shortened latency of motor-evoked potentials when al-lografts loaded with both neurotrophic factors were used, compared with allografts loaded with just one factor. Thus, the combination of both brain-derived neurotrophic factor and cili-ary neurotrophic factor-transfected bone marrow mesenchymal stem cells can greatly improve nerve injury.

  18. Observations on the migratory behaviour of Schwann cells from adult peripheral nerve explant cultures.

    Science.gov (United States)

    Crang, A J; Blakemore, W F

    1987-06-01

    The migration of Schwann cells from adult sciatic nerve explant cultures has been examined by time-lapse photomicrography. Analysis of Schwann cell migratory behaviour indicates that the initial outwandering by individual Schwann cells was random. Although chance cell-cell contacts resulted in temporary immobilization of pairs of cells, stable multicellular structures did not form during this initial phase. As local cell densities increased, Schwann cells assembled networks within which Schwann cell movement continued to be observed. A second form of Schwann cell outgrowth was observed from degenerating fibres in which arrays of highly oriented Schwann cells migrated away from their basal lamina tubes onto the culture dish. These observations of Schwann cell random migration, network self-assembly and coordinated extratubal migration are considered to highlight aspects of Schwann cell behaviour, independent of axonal influences, which may have relevance to their role in peripheral nerve repair following nerve section. PMID:3612187

  19. Laser-activated protein bands for peripheral nerve repair

    Science.gov (United States)

    Lauto, Antonio; Trickett, Rodney I.; Malik, Richard; Dawes, Judith M.; Owen, Earl R.

    1996-01-01

    A 100 micrometer core optical fiber-coupled 75 mW diode laser operating at a wavelength of 800 nm has been used in conjunction with a protein solder to stripe weld severed rat tibial nerves, reducing the long operating time required for microsurgical nerve repair. Welding is produced by selective laser denaturation of the protein based solder which contains the dye indocyanine green. Operating time for laser soldering was 10 plus or minus 5 min. (n equals 24) compared to 23 plus or minus 9 min (n equals 13) for microsuturing. The laser solder technique resulted in patent welds with a tensile strength of 15 plus or minus 5 g, while microsutured nerves had a tensile strength of 40 plus or minus 10 g. Histopathology of the laser soldered nerves, conducted immediately after surgery, displayed solder adhesion to the outer membrane with minimal damage to the inner axons of the nerves. An in vivo study, with a total of fifty-seven adult male wistar rats, compared laser solder repaired tibial nerves to conventional microsuture repair. Twenty-four laser soldered nerves and thirteen sutured nerves were characterized at three months and showed successful regeneration with average compound muscle action potentials (CMAP) of 2.4 plus or minus 0.7 mV and 2.7 plus or minus 0.8 mV respectively. Histopathology of the in vivo study, confirmed the comparable regeneration of axons in laser and suture operated nerves. A faster, less damaging and long lasting laser based anastomotic technique is presented.

  20. Involvement of Hypothalamic AMP-Activated Protein Kinase in Leptin-Induced Sympathetic Nerve Activation

    OpenAIRE

    Mamoru Tanida; Naoki Yamamoto; Toshishige Shibamoto; Kamal Rahmouni

    2013-01-01

    In mammals, leptin released from the white adipose tissue acts on the central nervous system to control feeding behavior, cardiovascular function, and energy metabolism. Central leptin activates sympathetic nerves that innervate the kidney, adipose tissue, and some abdominal organs in rats. AMP-activated protein kinase (AMPK) is essential in the intracellular signaling pathway involving the activation of leptin receptors (ObRb). We investigated the potential of AMPKα2 in the sympathetic effec...

  1. Transplantation of neural progenitor cells differentiated from adipose tissue-derived stem cells for treatment of sciatic nerve injury

    Institute of Scientific and Technical Information of China (English)

    Shasha Dong§; Na Liu§; Yang Hu ; Ping Zhang; Chao Pan; Youping Zhang; Yingxin Tang; Zhouping Tang 

    2016-01-01

    Objectives: Currently, the clinical repair of sciatic nerve injury remains difficult. Previous studies have confirmed that transplantation of adipose tissue-derived stem cells promotes nerve regeneration and restoration at peripheral nerve injury sites. Methods:In this study, adipose tissue-derived stem cells were induced to differentiate into neural progenitor cells, transfected with a green fluorescent protein-containing lentivirus, and then transplanted into the lesions of rats with sciatic nerve compression injury. Results: Fluorescence microscopy revealed that the transplanted cells survived, migrated, and differentiated in rats. At two weeks post-operation, a large number of transplanted cells had migrated to the injured lesions; at six weeks post-operation, transplanted cells were visible around the injured nerve and several cells were observed to express a Schwann cell marker. Sciatic function index and electrophysiological outcomes of the transplantation group were better than those of the control group. Cell transplantation promoted the recovery of motor nerve conduction velocity and com-pound muscle action potential amplitude, and reduced gastrocnemius muscle atrophy. Conclusions: Our experimental findings indicate that neural progenitor cells, differentiated from adipose tissue-derived stem cells, are potential seed stem cells that can be transplanted into lesions to treat sciatic nerve injury. This provides a theoretical basis for their use in clinical applications.

  2. Nanoparticles carrying neurotrophin-3-modified Schwann cells promote repair of sciatic nerve defects

    Institute of Scientific and Technical Information of China (English)

    Haibin Zong; Hongxing Zhao; Yilei Zhao; Jingling Jia; Libin Yang; Chao Ma; Yang Zhang; Yuzhen Dong

    2013-01-01

    Schwann cells and neurotrophin-3 play an important role in neural regeneration, but the secretion of neurotrophin-3 from Schwann cells is limited, and exogenous neurotrophin-3 is inactived easily in vivo. In this study, we have transfected neurotrophin-3 into Schwann cells cultured in vitro using nanoparticle liposomes. Results showed that neurotrophin-3 was successfully transfected into Schwann cells, where it was expressed effectively and steadily. A composite of Schwann cells transfected with neurotrophin-3 and poly(lactic-co-glycolic acid) biodegradable conduits was transplanted into rats to repair 10-mm sciatic nerve defects. Transplantation of the composite scaffold could restore the myoelectricity and wave amplitude of the sciatic nerve by electrophysiological examination, promote nerve axonal and myelin regeneration, and delay apoptosis of spinal motor neurons. Experimental findings indicate that neurotrophin-3 transfected Schwann cells combined with bridge grafting can promote neural regeneration and functional recovery after nerve injury.

  3. Vagus nerve stimulation for epilepsy activates the vocal folds maximally at therapeutic levels

    NARCIS (Netherlands)

    Ardesch, J.J.; Sikken, J.R.; Veltink, P.H.; Aa, van der H.E.; Hageman, G.; Buschman, H.P.J.

    2010-01-01

    Purpose Vagus nerve stimulation (VNS) for medically refractory epilepsy can give hoarseness due to stimulation of the recurrent laryngeal nerve. For a group of VNS-therapy users this side-effect interferes severely with their daily activities. Our goal was to investigate the severity of intra-operat

  4. Mechanisms mediating renal sympathetic nerve activation in obesity-related hypertension.

    Science.gov (United States)

    Chen, W; Leo, S; Weng, C; Yang, X; Wu, Y; Tang, X

    2015-04-01

    Excessive renal sympathetic nerve activation may be one of the mechanisms underlying obesity-related hypertension. Impaired baroreflex sensitivity, adipokine disorders-such as leptin, adiponectin, and resistin-activation of the renin-angiotensin system, hyperinsulinemia, insulin resistance, and renal sodium retention present in obesity increase renal sympathetic nerve activity, thus contributing to the development of hypertension. Renal sympathetic denervation reduces both renal sympathetic activity and blood pressure in patients with obesity-related hypertension. PMID:24609799

  5. Signals regulating myelination in peripheral nerves and the Schwann cell response to injury

    OpenAIRE

    Glenn, Thomas D.; William S Talbot

    2013-01-01

    In peripheral nerves, Schwann cells form myelin, which facilitates the rapid conduction of action potentials along axons in the vertebrate nervous system. Myelinating Schwann cells are derived from neural crest progenitors in a step-wise process that is regulated by extracellular signals and transcription factors. In addition to forming the myelin sheath, Schwann cells orchestrate much of the regenerative response that occurs after injury to peripheral nerves. In response to injury, myelinati...

  6. Effects of leptin on sympathetic nerve activity in conscious mice.

    Science.gov (United States)

    Morgan, Donald A; Despas, Fabien; Rahmouni, Kamal

    2015-09-01

    The adipocyte-derived hormone, leptin, has emerged as an important regulator of regional sympathetic nerve activity (SNA) with pathophysiological implications in obesity. Genetically engineered mice are useful to understand the molecular pathways underlying the SNA responses evoked by leptin. However, so far the effect of leptin on direct SNA in mice has been studied under general anesthesia. Here, we examined the sympathetic responses evoked by leptin in conscious mice. Mice were instrumented, under ketamine/xylazine anesthesia, with renal or lumbar SNA recordings using a thin (40 gauge) bipolar platinum-iridium wire. The electrodes were exteriorized at the nape of the neck and mice were allowed (5 h) to recover from anesthesia. Interestingly, the reflex increases in renal and lumbar SNA caused by sodium nitroprusside (SNP)-induced hypotension was higher in the conscious phase versus the anesthetized state, whereas the increase in both renal and lumbar SNA evoked by leptin did not differ between anesthetized or conscious mice. Next, we assessed whether isoflurane anesthesia would yield a better outcome. Again, the SNP-induced increase in renal SNA and baroreceptor-renal SNA reflex were significantly elevated in the conscious states relative to isoflurane-anesthetized phase, but the renal SNA response induced by leptin in the conscious states were qualitatively comparable to those evoked above. Thus, despite improvement in sympathetic reflexes in conscious mice the sympathetic responses evoked by leptin mimic those induced during anesthesia. PMID:26381017

  7. Physiological properties of vertebrate nerve cells in tissue culture.

    Science.gov (United States)

    Dichter, M A

    1975-01-01

    Vertebrate neurons in tissue culture are providing us with a new model system for studying the complex events which occur during neuronal differentiation, synaptogenesis, and neural network formation. It is already apparent that dissociated embryo neurons are capable of differentiating both morphologically and physiologically along predetermined lines in the absence of external influences. These neurons can form new connections with one another but retain some specificity in their selections. Both simple and complex neural networks can be seen. At the present time, the development of the invitro model system is just being explored. The potential value of a system of this kind at a variety of investigative levels should be appreciated. Questions of a fundamental nature in neurobiology, such as how synapses form, what rules govern such interaction, how cells recognize one another, and the nature of the basic two-, three-, or four-cell circuits that comprise the more complex neurons tissue can be approached with this system. Studies of the neurons and synapses themselves can lead to a more basic understanding of vertebrate nervous system functioning. The development of certain pathophysiological processes and the effects of neuroactive drugs on vertebrate neurons may be studied at the cellular level. Finally, the basic mechanism of some genetic abnormalities which produce abnormal nervous structure and function may be more easily determined in a simplified in vitro model than in the intact central nervous system. The value of any model is not inherent in the elegance of the model itseld, but only in its ability to suggest answers to fundamental questions about the system being modeled. Many fundamental questions about brain mechanisms in mental retardation remain unanswered. Perhaps some day the model of nerve cells in tissue culture will bring us closer to the answers to these questions. PMID:173059

  8. Influence of Different Geometric Representations of the Volume Conductor on Nerve Activation during Electrical Stimulation

    Directory of Open Access Journals (Sweden)

    José Gómez-Tames

    2014-01-01

    Full Text Available Volume conductor models with different geometric representations, such as the parallel layer model (PM, the cylindrical layer model (CM, or the anatomically based model (AM, have been employed during the implementation of bioelectrical models for electrical stimulation (FES. Evaluating their strengths and limitations to predict nerve activation is fundamental to achieve a good trade-off between accuracy and computation time. However, there are no studies aimed at clarifying the following questions. (1 Does the nerve activation differ between CM and PM? (2 How well do CM and PM approximate an AM? (3 What is the effect of the presence of blood vessels and nerve trunk on nerve activation prediction? Therefore, in this study, we addressed these questions by comparing nerve activation between CM, PM, and AM models by FES. The activation threshold was used to evaluate the models under different configurations of superficial electrodes (size and distance, nerve depths, and stimulation sites. Additionally, the influences of the sciatic nerve, femoral artery, and femoral vein were inspected for a human thigh. The results showed that the CM and PM had a high error rate, but the variation of the activation threshold followed the same tendency for electrode size and interelectrode distance variation as AM.

  9. A comparison between complete immobilisation and protected active mobilisation in sensory nerve recovery following isolated digital nerve injury.

    LENUS (Irish Health Repository)

    Henry, F P

    2012-06-01

    Post-operative immobilisation following isolated digital nerve repair remains a controversial issue amongst the microsurgical community. Protocols differ from unit to unit and even, as evidenced in our unit, may differ from consultant to consultant. We undertook a retrospective review of 46 patients who underwent isolated digital nerve repair over a 6-month period. Follow-up ranged from 6 to 18 months. Twenty-four were managed with protected active mobilisation over a 4-week period while 22 were immobilised over the same period. Outcomes such as return to work, cold intolerance, two-point discrimination and temperature differentiation were used as indicators of clinical recovery. Our results showed that there was no significant difference noted in either clinical assessment of recovery or return to work following either post-operative protocol, suggesting that either regime may be adopted, tailored to the patient\\'s needs and resources of the unit.

  10. Protection by an oral disubstituted hydroxylamine derivative against loss of retinal ganglion cell differentiation following optic nerve crush.

    Directory of Open Access Journals (Sweden)

    James D Lindsey

    Full Text Available Thy-1 is a cell surface protein that is expressed during the differentiation of retinal ganglion cells (RGCs. Optic nerve injury induces progressive loss in the number of RGCs expressing Thy-1. The rate of this loss is fastest during the first week after optic nerve injury and slower in subsequent weeks. This study was undertaken to determine whether oral treatment with a water-soluble N-hydroxy-2,2,6,6-tetramethylpiperidine derivative (OT-440 protects against loss of Thy-1 promoter activation following optic nerve crush and whether this effect targets the earlier quick phase or the later slow phase. The retina of mice expressing cyan fluorescent protein under control of the Thy-1 promoter (Thy1-CFP mice was imaged using a blue-light confocal scanning laser ophthalmoscope (bCSLO. These mice then received oral OT-440 prepared in cream cheese or dissolved in water, or plain vehicle, for two weeks and were imaged again prior to unilateral optic nerve crush. Treatments and weekly imaging continued for four more weeks. Fluorescent neurons were counted in the same defined retinal areas imaged at each time point in a masked fashion. When the counts at each time point were directly compared, the numbers of fluorescent cells at each time point were greater in the animals that received OT-440 in cream cheese by 8%, 27%, 52% and 60% than in corresponding control animals at 1, 2, 3 and 4 weeks after optic nerve crush. Similar results were obtained when the vehicle was water. Rate analysis indicated the protective effect of OT-440 was greatest during the first two weeks and was maintained in the second two weeks after crush for both the cream cheese vehicle study and water vehicle study. Because most of the fluorescent cells detected by bCSLO are RGCs, these findings suggest that oral OT-440 can either protect against or delay early degenerative responses occurring in RGCs following optic nerve injury.

  11. Regeneration of the auditory nerve - a cell transplantation study

    OpenAIRE

    Palmgren, Björn

    2011-01-01

    Since in mammals, the hair cells or the spiral ganglion neurons (SGNs) in the inner ear do not regenerate, damage to these cells is an irreversible process. Presently the only aid for patients with severe to profound hearing impairment due to damaged hair cells is a cochlear implant (CI). A CI converts sound to electrical signals that stimulate the SGNs via an electrode that is implanted into the cochlea. Hence, for a successful outcome the CI is dependant on the activation ...

  12. Axonal elongation through long acellular nerve segments depends on recruitment of phagocytic cells from the near-nerve environment. Electrophysiological and morphological studies in the cat

    DEFF Research Database (Denmark)

    Sørensen, J; Fugleholm, K; Moldovan, M;

    2001-01-01

    or tissue ingrowth, respectively. In a second set of experiments, tibial nerves were crushed and either frozen for 20+20 mm, leaving a 10 mm segment with viable cells in the center (stepping-stone segment) or frozen for 50 mm. These nerves were enclosed in cuffs with 2.0 mm holes corresponding to the viable...

  13. Effects of nerve growth factor on X-irradiated reaggregation cultures of rat brain cells

    Energy Technology Data Exchange (ETDEWEB)

    Dimberg, Y. (Swedish Univ. of Agricultural Sciences, Uppsala (Sweden)); Aspberg, A.; Tottmar, O. (Uppsala Univ. (Sweden). Dept. of Zoophysiology)

    1993-12-01

    The effects of exogenously added nerve growth factor (NGF) on reaggregation cultures of foetal rat brain cells after X-irradiation with 2 Gy were studied. Irradiation caused decreased protein and DNA levels, which was not prevented by NGF. The activities of the cholinergic marker enzymes choline acetyl transferase and acetylcholine esterase were increased in irradiated cultures. However, no difference in the activities of these enzymes was found between irradiated and unirradiated NGF-treated cultures. Irradiation did not affect the activity of the marker enzyme for oligodendrocytes (2',3'-cyclic nucleotide 3'-phosphodiesterase), but caused an increase in the astrocyte marker (glutamine synthetase) activity. This effect on astrocytes was prevented by NGF. (Author).

  14. Effects of nerve growth factor on X-irradiated reaggregation cultures of rat brain cells.

    Science.gov (United States)

    Dimberg, Y; Aspberg, A; Tottmar, O

    1993-12-01

    The effects of exogenously added nerve growth factor (NGF) on reaggregation cultures of foetal rat brain cells after X-irradiation with 2 Gy were studied. Irradiation caused decreased protein and DNA levels, which was not prevented by NGF. The activities of the cholinergic marker enzymes choline acetyl transferase and acetylcholine esterase were increased in irradiated cultures. However, no difference in the activities of these enzymes was found between irradiated and unirradiated NGF-treated cultures. Irradiation did not affect the activity of the marker enzyme for oligodendrocytes (2',3'-cyclic nucleotide 3'-phosphodiesterase), but caused an increase in the astrocyte marker (glutamine synthetase) activity. This effect on astrocytes was prevented by NGF. PMID:7903341

  15. [Construction of recombinant human nerve growth factor (rh-β-NGF) eukaryotic vector and its expression in HEK293 cells].

    Science.gov (United States)

    Li, Jingchuan; Xue, Bofu; Yuan, Yuan; Ma, Mo; Zhu, Lin; Milburn, Rebecca; Le, Li; Hu, Peizhen; Ye, Jing

    2015-03-01

    Human nerve growth factor (NGF) is a nerve cell growth regulation factor, which can provide nutrition for the neurons and promote the neurites outgrowth. In order to produce large-scale recombinant human nerve growth factor (rh-beta-NGF), we constructed a plasmid vector, which can stably express the rh-beta-NGF in the HEK293 cell lines. First, the plasmid of pCMV-beta-NGF-IRES-dhfr was constructed and transformed into HEK293 cells. Then MTX pressurized filter and limiting dilution methods were used to obtain monoclonal HEK293 cell lines. After stepwise reducing serum in culture media, the cells eventually adapted to serum-free medium and secreted rh-beta-NGF. SDS-PAGE analysis revealed that the expression product owned a molecular weight of about 13 kDa and a purity of more than 50%. The peptide mapping sequencing analysis demonstrated the sequences of rh-beta-NGF matched with the theoretical ones. Later we purified this protein by ion exchange and molecular sieve chromatograph. Finally, our experimental results exhibited that the recombinant cell lines can stably express rh-beta-NGF with a high efficiency of more than 20 pg/cell x day. In addition, this protein could successfully induce differentiation of PC12 cells. In summary, our recombinant HEK293 cells can express bio-active rh-beta-NGF with great efficiency and stability, which supply a valid basis to large-scale production of rh-beta-NGF.

  16. Novel Method To Differentiate Human Embryonic Stem Cells Into Dopaminergic Nerve Cells | NCI Technology Transfer Center | TTC

    Science.gov (United States)

    The National Institute on Drug Abuse's Development and Plasticity Section is seeking statements of capability or interest from parties interested in collaborative research to further develop, evaluate, or commercialize novel methods to differentiate human embryonic stem cells into dopaminergic nerve cells. The invention described here is a novel method of differentiating human embryonic stem cells (hESCs) into dopaminergic nerve cells, which is preferable to the currently available dopaminergic differentiation techniques.

  17. Acellular allogeneic nerve grafting combined with bone marrow mesenchymal stem cell transplantation for the repair of long-segment sciatic nerve defects:biomechanics and validation of mathematical models

    Institute of Scientific and Technical Information of China (English)

    Ya-jun Li; Bao-lin Zhao; Hao-ze Lv; Zhi-gang Qin; Min Luo

    2016-01-01

    We hypothesized that a chemically extracted acellular allogeneic nerve graft used in combination with bone marrow mesenchymal stem cell transplantation would be an effective treatment for long-segment sciatic nerve defects. To test this, we established rabbit models of 30 mm sciatic nerve defects, and treated them using either an autograft or a chemically decellularized allogeneic nerve graft with or without simultaneous transplantation of bone marrow mesenchymal stem cells. We compared the tensile properties, electrophysiological function and morphology of the damaged nerve in each group. Sciatic nerves repaired by the allogeneic nerve graft combined with stem cell trans-plantation showed better recovery than those repaired by the acellular allogeneic nerve graft alone, and produced similar results to those observed with the autograft. These ifndings conifrm that a chemically extracted acellular allogeneic nerve graft combined with transplanta-tion of bone marrow mesenchymal stem cells is an effective method of repairing long-segment sciatic nerve defects.

  18. Trigeminal nerve involvement in T-cell acute lymphoblastic leukemia: value of MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Karadag, Demet; Karaguelle, Ayse Tuba; Erden, Ilhan; Erden, Ayse E-mail: erden@ada.net.tr

    2002-10-01

    A 30-year-old male with T-cell acute lymphoblastic leukemia presented with facial numbness. Neurological examination revealed paresthesia of the left trigeminal nerve. Cerebrospinal fluid (CSF) cytology showed no atypical cells. Gadolinium-enhanced magnetic resonance (MR) imaging demonstrated enlargement and enhancement of intracranial portions of the left trigeminal nerve. The abnormal MR imaging findings almost completely resolved after the chemotherapy. Gadolinium-enhanced MR imaging is not only a useful procedure for the early diagnosis of cranial nerve invasion by leukemia but it might be helpful to follow the changes after the treatment.

  19. Comparison of sympathetic nerve activity normalization procedures in conscious rabbits.

    Science.gov (United States)

    Burke, Sandra L; Lim, Kyungjoon; Moretti, John-Luis; Head, Geoffrey A

    2016-05-01

    One of the main constraints associated with recording sympathetic nerve activity (SNA) in both humans and experimental animals is that microvolt values reflect characteristics of the recording conditions and limit comparisons between different experimental groups. The nasopharyngeal response has been validated for normalizing renal SNA (RSNA) in conscious rabbits, and in humans muscle SNA is normalized to the maximum burst in the resting period. We compared these two methods of normalization to determine whether either could detect elevated RSNA in hypertensive rabbits compared with normotensive controls. We also tested whether either method eliminated differences based only on different recording conditions by separating RSNA of control (sham) rabbits into two groups with low or high microvolts. Hypertension was induced by 5 wk of renal clipping (2K1C), 3 wk of high-fat diet (HFD), or 3 mo infusion of a low dose of angiotensin (ANG II). Normalization to the nasopharyngeal response revealed RSNA that was 88, 51, and 34% greater in 2K1C, HFD, and ANG II rabbits, respectively, than shams (P < 0.05), but normalization to the maximum burst showed no differences. The RSNA baroreflex followed a similar pattern whether RSNA was expressed in microvolts or normalized. Both methods abolished the difference between low and high microvolt RSNA. These results suggest that maximum burst amplitude is a useful technique for minimizing differences between recording conditions but is unable to detect real differences between groups. We conclude that the nasopharyngeal reflex is the superior method for normalizing sympathetic recordings in conscious rabbits. PMID:26921439

  20. Platelet-rich plasma gel in combination with Schwann cells for repair of sciatic nerve injury☆

    OpenAIRE

    Ye, Fagang; Li, Haiyan; Qiao, Guangxi; Chen, Feng; Tao, Hao; Ji, Aiyu; Hu, Yanling

    2012-01-01

    Bone marrow mesenchymal stem cells were isolated from New Zealand white rabbits, culture-expanded and differentiated into Schwann cell-like cells. Autologous platelet-rich plasma and Schwann cell-like cells were mixed in suspension at a density of 1 × 106 cells/mL, prior to introduction into a poly (lactic-co-glycolic acid) conduit. Fabricated tissue-engineered nerves were implanted into rabbits to bridge 10 mm sciatic nerve defects (platelet-rich plasma group). Controls were established usin...

  1. Involvement of hypothalamic AMP-activated protein kinase in leptin-induced sympathetic nerve activation.

    Directory of Open Access Journals (Sweden)

    Mamoru Tanida

    Full Text Available In mammals, leptin released from the white adipose tissue acts on the central nervous system to control feeding behavior, cardiovascular function, and energy metabolism. Central leptin activates sympathetic nerves that innervate the kidney, adipose tissue, and some abdominal organs in rats. AMP-activated protein kinase (AMPK is essential in the intracellular signaling pathway involving the activation of leptin receptors (ObRb. We investigated the potential of AMPKα2 in the sympathetic effects of leptin using in vivo siRNA injection to knockdown AMPKα2 in rats, to produce reduced hypothalamic AMPKα2 expression. Leptin effects on body weight, food intake, and blood FFA levels were eliminated in AMPKα2 siRNA-treated rats. Leptin-evoked enhancements of the sympathetic nerve outflows to the kidney, brown and white adipose tissues were attenuated in AMPKα2 siRNA-treated rats. To check whether AMPKα2 was specific to sympathetic changes induced by leptin, we examined the effects of injecting MT-II, a melanocortin-3 and -4 receptor agonist, on the sympathetic nerve outflows to the kidney and adipose tissue. MT-II-induced sympatho-excitation in the kidney was unchanged in AMPKα2 siRNA-treated rats. However, responses of neural activities involving adipose tissue to MT-II were attenuated in AMPKα2 siRNA-treated rats. These results suggest that hypothalamic AMPKα2 is involved not only in appetite and body weight regulation but also in the regulation of sympathetic nerve discharges to the kidney and adipose tissue. Thus, AMPK might function not only as an energy sensor, but as a key molecule in the cardiovascular, thermogenic, and lipolytic effects of leptin through the sympathetic nervous system.

  2. Synergistic effects of low-level laser and mesenchymal stem cells on functional recovery in rats with crushed sciatic nerves.

    Science.gov (United States)

    Yang, Chen-Chia; Wang, John; Chen, Shyh-Chang; Hsieh, Yueh-Ling

    2016-02-01

    Transplantation of mesenchymal stem cells (MSCs) has been proposed to exert beneficial effects on peripheral nerve regeneration after a peripheral nerve injury, but the functional recovery in the denervated limb is still limited. In this study, we used low-level laser therapy (LLLT) as an adjunct therapy for MSC transplantation on the functional recovery of crushed sciatic nerve in rats. Peripheral nerve injury was induced in 48 Sprague-Dawley rats by crushing the unilateral sciatic nerve, using a vessel clamp. The animals with crushed injury were randomly divided into four groups: control group, with no treatment; MSC group, treated with MSC alone; LLLT group, treated with LLLT alone; and MSCLLLT group, treated with a combination of MSC and LLLT. The sciatic function index (SFI), vertical activity of locomotion (VA) and ankle angle (AA) of rats were examined for functional assessments after treatment. Electrophysiological, morphological and S100 immunohistochemical studies were also conducted. The MSCLLLT group showed a greater recovery in SFI, VA and AA, with significant difference from MSC, LLLT and control groups (p crush injury in the MSCLLLT group when compared with the groups receiving a single treatment (p crush injury. PMID:23468370

  3. Dark rearing maintains tyrosine hydroxylase expression in retinal amacrine cells following optic nerve transection

    Institute of Scientific and Technical Information of China (English)

    Wei Wan; Zhenghai Liu; Xiaosheng Wang; Xuegang Luo

    2012-01-01

    The present study examined changes in retinal tyrosine hydroxylase (TH) expression in rats having undergone optic nerve transection and housed under a normal day/night cycle or in the dark. The aim was to investigate the effects of amacrine cells on axonal regeneration in retinal ganglion cells and on the synapses that transmit visual signals. The results revealed that retinal TH expression gradually decreased following optic nerve transection in rats housed under a normal day/night cycle, reaching a minimum at 5 days. In contrast, retinal TH expression decreased to a minimum at 1 day following optic nerve transection in dark reared rats, gradually increasing afterward and reaching a normal level at 5-7 days. The number of TH-positive synaptic particles correlated with the TH levels, indicating that dark rearing can help maintain TH expression during the synaptic degeneration stage (5-7 days after optic nerve injury) in retinal amacrine cells.

  4. Senescence in adipose-derived stem cells and its implications in nerve regeneration

    Institute of Scientific and Technical Information of China (English)

    Cristina Mantovani; Giorgio Terenghi; Valerio Magnaghi

    2014-01-01

    Adult mesenchymal stem cells, specifically adipose-derived stem cells have self-renewal and multiple differentiation potentials and have shown to be the ideal candidate for therapeutic applications in regenerative medicine, particularly in peripheral nerve regeneration. Adipose-de-rived stem cells are easily harvested, although they may show the effects of aging, hence their potential in nerve repair may be limited by cellular senescence or donor age. Cellular senescence is a complex process whereby stem cells grow old as consequence of intrinsic events (e.g., DNA damage) or environmental cues (e.g., stressful stimuli or diseases), which determine a permanent growth arrest. Several mechanisms are implicated in stem cell senescence, although no one is exclusive of the others. In this review we report some of the most important factors modulating the senescence process, which can inlfuence adipose-derived stem cell morphology and function, and compromise their clinical application for peripheral nerve regenerative cell therapy.

  5. Macrophage polarization in nerve injury:do Schwann cells play a role?

    Institute of Scientific and Technical Information of China (English)

    Jo Anne Stratton; Prajay T Shah

    2016-01-01

    In response to peripheral nerve injury, the inlfammatory response is almost entirely comprised of inifltrat-ing macrophages. Macrophages are a highly plastic, heterogenic immune cell, playing an indispensable role in peripheral nerve injury, clearing debris and regulating the microenvironment to allow for efifcient regen-eration. There are several cells within the microenvironment that likely interact with macrophages to support their function –most notably the Schwann cell, the glial cell of the peripheral nervous system. Schwann cells express several ligands that are known to interact with receptors expressed by macrophages, yet the effects of Schwann cells in regulating macrophage phenotype remains largely unexplored. This review discusses macrophages in peripheral nerve injury and how Schwann cells may regulate their behavior.

  6. Platelet-rich plasma gel in combination with Schwann cells for repair of sciatic nerve injury

    Institute of Scientific and Technical Information of China (English)

    Fagang Ye; Haiyan Li; Guangxi Qiao; Feng Chen; Hao Tao; Aiyu Ji; Yanling Hu

    2012-01-01

    Bone marrow mesenchymal stem cells were isolated from New Zealand white rabbits,culture-expanded and differentiated into Schwann cell-like cells.Autologous platelet-rich plasma and Schwann cell-like cells were mixed in suspension at a density of 1 × 106 cells/mL,prior to introduction into a poly (lactic-co-glycolic acid) conduit.Fabricated tissue-engineered nerves were implanted into rabbits to bridge 10 mm sciatic nerve defects (platelet-rich plasma group).Controls were established using fibrin as the seeding matrix for Schwann cell-like cells at identical density to construct tissue-engineered nerves (fibrin group).Twelve weeks after implantation,toluidine blue staining and scanning electron microscopy were used to demonstrate an increase in the number of regenerating nerve fibers and thickness of the myelin sheath in the platelet-rich plasma group compared with the fibrin group.Fluoro-gold retrograde labeling revealed that the number of Fluoro-gold-positive neurons in the dorsal root ganglion and the spinal cord anterior horn was greater in the platelet-rich plasma group than in the fibrin group.Electrophysiological examination confirmed that compound muscle action potential and nerve conduction velocity were superior in the platelet-rich plasma group compared with the fibrin group.These results indicate that autologous platelet-rich plasma gel can effectively serve as a seeding matrix for Schwann cell-like cells to construct tissue-engineered nerves to promote peripheral nerve regeneration.

  7. Stem cell therapy for central nerve system injuries:glial cells hold the key

    Institute of Scientific and Technical Information of China (English)

    Li Xiao; Chikako Saiki; Ryoji Ide

    2014-01-01

    Mammalian adult central nerve system (CNS) injuries are devastating because of the intrinsic dififculties for effective neuronal regeneration. The greatest problem to be overcome for CNS recovery is the poor regeneration of neurons and myelin-forming cells, oligodendrocytes. En-dogenous neural progenitors and transplanted exogenous neuronal stem cells can be the source for neuronal regeneration. However, because of the harsh local microenvironment, they usually have very low efifcacy for functional neural regeneration which cannot compensate for the loss of neurons and oligodendrocytes. Glial cells (including astrocytes, microglia, oligodendrocytes and NG2 glia) are the majority of cells in CNS that provide support and protection for neurons. Inside the local microenvironment, glial cells largely inlfuence local and transplanted neural stem cells survival and fates. This review critically analyzes current ifnding of the roles of glial cells in CNS regeneration, and highlights strategies for regulating glial cells’ behavior to create a permis-sive microenvironment for neuronal stem cells.

  8. Autophagy is involved in the reduction of myelinating Schwann cell cytoplasm during myelin maturation of the peripheral nerve.

    Directory of Open Access Journals (Sweden)

    So Young Jang

    Full Text Available Peripheral nerve myelination involves dynamic changes in Schwann cell morphology and membrane structure. Recent studies have demonstrated that autophagy regulates organelle biogenesis and plasma membrane dynamics. In the present study, we investigated the role of autophagy in the development and differentiation of myelinating Schwann cells during sciatic nerve myelination. Electron microscopy and biochemical assays have shown that Schwann cells remove excess cytoplasmic organelles during myelination through macroautophagy. Inhibition of autophagy via Schwann cell-specific removal of ATG7, an essential molecule for macroautophagy, using a conditional knockout strategy, resulted in abnormally enlarged abaxonal cytoplasm in myelinating Schwann cells that contained a large number of ribosomes and an atypically expanded endoplasmic reticulum. Small fiber hypermyelination and minor anomalous peripheral nerve functions are observed in this mutant. Rapamycin-induced suppression of mTOR activity during the early postnatal period enhanced not only autophagy but also developmental reduction of myelinating Schwann cells cytoplasm in vivo. Together, our findings suggest that autophagy is a regulatory mechanism of Schwann cells structural plasticity during myelination.

  9. Stem cells and related factors involved in facial nerve function regeneration.

    Science.gov (United States)

    Nelke, Kamil H; Łuczak, Klaudiusz; Pawlak, Wojciech; Łysenko, Lidia; Gerber, Hanna

    2015-01-01

    The facial nerve (VII) is one of the most important cranial nerves for head and neck surgeons. Its function is closely related to facial expressions that are individual for every person. After its injury or palsy, its functions can be either impaired or absent. Because of the presence of motor, sensory and parasympathetic fibers, the biology of its repair and function restoration depends on many factors. In order to achieve good outcome, many different therapies can be performed in order to restore as much of the nerve function as possible. When rehabilitation and physiotherapy are not sufficient, additional surgical procedures and therapies are taken into serious consideration. The final outcome of many of them is discussable, depending on nerve damage etiology. Stem cells in facial nerve repair are used, but long-term outcomes and results are still not fully known. In order to understand this therapeutic approach, clinicians and surgeons should understand the immunobiology of nerve repair and regeneration. In this review, potential stem cell usage in facial nerve regeneration procedures is discussed. PMID:26400886

  10. Nerve growth factor promotes in vitro proliferation of neural stem cells from tree shrews

    Directory of Open Access Journals (Sweden)

    Liu-lin Xiong

    2016-01-01

    Full Text Available Neural stem cells promote neuronal regeneration and repair of brain tissue after injury, but have limited resources and proliferative ability in vivo. We hypothesized that nerve growth factor would promote in vitro proliferation of neural stem cells derived from the tree shrews, a primate-like mammal that has been proposed as an alternative to primates in biomedical translational research. We cultured neural stem cells from the hippocampus of tree shrews at embryonic day 38, and added nerve growth factor (100 µg/L to the culture medium. Neural stem cells from the hippocampus of tree shrews cultured without nerve growth factor were used as controls. After 3 days, fluorescence microscopy after DAPI and nestin staining revealed that the number of neurospheres and DAPI/nestin-positive cells was markedly greater in the nerve growth factor-treated cells than in control cells. These findings demonstrate that nerve growth factor promotes the proliferation of neural stem cells derived from tree shrews.

  11. Hydrogen sulfide is essential for Schwann cell responses to peripheral nerve injury.

    Science.gov (United States)

    Park, Byung Sun; Kim, Hyun-Wook; Rhyu, Im Joo; Park, Chan; Yeo, Seung Geun; Huh, Youngbuhm; Jeong, Na Young; Jung, Junyang

    2015-01-01

    Hydrogen sulfide (H2 S) functions as a physiological gas transmitter in both normal and pathophysiological cellular events. H2 S is produced from substances by three enzymes: cystathionine β-synthase (CBS), cystathionine γ-lyase (CSE), and 3-mercaptopyruvate sulfurtransferase (MST). In human tissues, these enzymes are involved in tissue-specific biochemical pathways for H2 S production. For example, CBS and cysteine aminotransferase/MST are present in the brain, but CSE is not. Thus, we examined the expression of H2 S production-related enzymes in peripheral nerves. Here, we found that CSE and MST/cysteine aminotransferase, but not CBS, were present in normal peripheral nerves. In addition, injured sciatic nerves in vivo up-regulated CSE in Schwann cells during Wallerian degeneration (WD); however, CSE was not up-regulated in peripheral axons. Using an ex vivo sciatic nerve explant culture, we found that the inhibition of H2 S production broadly prevented the process of nerve degeneration, including myelin fragmentation, axonal degradation, Schwann cell dedifferentiation, and Schwann cell proliferation in vitro and in vivo. Thus, these results indicate that H2 S signaling is essential for Schwann cell responses to peripheral nerve injury. Hydrogen sulfide (H2 S) functions as a physiological gas transmitter in both normal and pathophysiological cellular events. H2 S is produced from cystathionine β-synthase (CBS), cystathionine γ-lyase (CSE), and 3-mercaptopyruvate sulfur transferase (MST). Here, we found that CSE and MST/CAT were present in normal peripheral nerves. Injured static nerves in vivo up-regulated CSE in Schwann cells during Wallerian degeneration, but CSE was not up-regulated in peripheral axons.

  12. A nerve guidance conduit with topographical and biochemical cues: potential application using human neural stem cells

    Science.gov (United States)

    Jenkins, Phillip M.; Laughter, Melissa R.; Lee, David J.; Lee, Young M.; Freed, Curt R.; Park, Daewon

    2015-06-01

    Despite major advances in the pathophysiological understanding of peripheral nerve damage, the treatment of nerve injuries still remains an unmet medical need. Nerve guidance conduits present a promising treatment option by providing a growth-permissive environment that 1) promotes neuronal cell survival and axon growth and 2) directs axonal extension. To this end, we designed an electrospun nerve guidance conduit using a blend of polyurea and poly-caprolactone with both biochemical and topographical cues. Biochemical cues were integrated into the conduit by functionalizing the polyurea with RGD to improve cell attachment. Topographical cues that resemble natural nerve tissue were incorporated by introducing intraluminal microchannels aligned with nanofibers. We determined that electrospinning the polymer solution across a two electrode system with dissolvable sucrose fibers produced a polymer conduit with the appropriate biomimetic properties. Human neural stem cells were cultured on the conduit to evaluate its ability to promote neuronal growth and axonal extension. The nerve guidance conduit was shown to enhance cell survival, migration, and guide neurite extension.

  13. Distribution of Neuron Cell Bodies in the Intraspinal Portion of the Spinal Accessory Nerve in Humans.

    Science.gov (United States)

    Boehm, Karl E; Kondrashov, Peter

    2016-01-01

    The spinal accessory nerve is often identified as a purely motor nerve innervating the trapezius and sternocleidomastoid muscles. Although it may contain proprioceptive neurons found in cervical spinal levels C2-C4, limited research has focused on the histology of the spinal accessory nerve. The objective of the present study was to examine the spinal accessory nerve to determine if there are neuronal cell bodies within the spinal accessory nerve in humans. Cervical spinal cords were dissected from eight cadavers that had previously been used for dissection in other body regions. The segmental rootlets were removed to quantify the neuron cell bodies present at each spinal level. Samples were embedded in paraffin; sectioned; stained with hematoxylin and eosin; and examined using a microscope at 4×, 10×, and 40× magnification. Digital photography was used to image the samples. Neuronal cell bodies were found in 100% of the specimens examined, with non-grossly visible ganglia found at spinal levels C1-C4. The C1 spinal level of the spinal accessory nerve had the highest number of neuron cell bodies.

  14. Intramuscular injection of bone marrow mesenchymal stem cells with small gap neurorrhaphy for peripheral nerve repair.

    Science.gov (United States)

    Wang, Peiji; Zhang, Yong; Zhao, Jiaju; Jiang, Bo

    2015-01-12

    We had previously reported that small gap neurorrhaphy by scissoring and sleeve-jointing epineurium could enhance the rate and quality of peripheral nerve regeneration. To date, local implantation and systemic delivery of bone marrow mesenchymal stem cells (BMSCs) have been routinely used in nerve tissue engineering, but they each have some intrinsic limitations. We hypothesised that targeted muscular administration of BMSCs capable of reaching the damaged nerve would be advisable. Here, we investigated the therapeutic efficacy of transplantation of BMSCs through targeted muscular injection with small gap neurorrhaphy by scissoring and sleeve-jointing epineurium on repairing peripheral nerve injury in a rat model. One week after a rat model of peripheral nerve injury was established by small gap neurorrhaphy, thirty-six Sprague-Dawley rats were randomly divided into three groups (n=12): the intramuscular injection of BMSCs group (IM), the intravenous injection of BMSCs group (IV) and the intramuscular injection of phosphate-buffered solution group (PBS). The process of the nerve regeneration was assayed functionally and morphologically. The results indicated that compared to the IV-treated and PBS-treated groups, the targeted muscular injection therapy resulted in much more beneficial effects, as evidenced by increases in the sciatic function index, nerve conduction velocity, myelin sheath thickness and restoration rate of gastrocnemius muscle wet weight. In conclusion, the combination therapy of small gap neurorrhaphy and BMSC transplantation through targeted muscular injection can significantly promote the regeneration of peripheral nerve and improve the nerve's functional recovery, which may help establish a reliable approach for repairing peripheral nerve injury. PMID:25434870

  15. Fabrication of bioactive conduits containing the fibroblast growth factor 1 and neural stem cells for peripheral nerve regeneration across a 15 mm critical gap.

    Science.gov (United States)

    Ni, Hsiao-Chiang; Tseng, Ting-Chen; Chen, Jeng-Rung; Hsu, Shan-Hui; Chiu, Ing-Ming

    2013-09-01

    Nerve conduits are often used in combination with bioactive molecules and stem cells to enhance peripheral nerve regeneration. In this study, the acidic fibroblast growth factor 1 (FGF1) was immobilized onto the microporous/micropatterned poly (D, L-lactic acid) (PLA) nerve conduits after open air plasma treatment. PLA substrates grafted with chitosan in the presence of a small amount of gold nanoparticles (nano Au) showed a protective effect on the activity of the immobilized FGF1 in vitro. Different conduits were tested for their ability to bridge a 15 mm critical gap defect in a rat sciatic nerve injury model. Axon regeneration and functional recovery were evaluated by histology, walking track analysis and electrophysiology. Among different conduits, PLA conduits grafted with chitosan-nano Au and the FGF1 after plasma activation had the greatest regeneration capacity and functional recovery in the experimental animals. When the above conduit was seeded with aligned neural stem cells, the efficacy was further enhanced and it approached that of the autograft group. This work suggested that microporous/micropatterned nerve conduits containing bioactive growth factors may be successfully fabricated by micropatterning techniques, open plasma activation, and immobilization, which, combined with aligned stem cells, may synergistically contribute to the regeneration of the severely damaged peripheral nerve. PMID:23880639

  16. Fabrication of bioactive conduits containing the fibroblast growth factor 1 and neural stem cells for peripheral nerve regeneration across a 15 mm critical gap

    International Nuclear Information System (INIS)

    Nerve conduits are often used in combination with bioactive molecules and stem cells to enhance peripheral nerve regeneration. In this study, the acidic fibroblast growth factor 1 (FGF1) was immobilized onto the microporous/micropatterned poly (D, L-lactic acid) (PLA) nerve conduits after open air plasma treatment. PLA substrates grafted with chitosan in the presence of a small amount of gold nanoparticles (nano Au) showed a protective effect on the activity of the immobilized FGF1 in vitro. Different conduits were tested for their ability to bridge a 15 mm critical gap defect in a rat sciatic nerve injury model. Axon regeneration and functional recovery were evaluated by histology, walking track analysis and electrophysiology. Among different conduits, PLA conduits grafted with chitosan–nano Au and the FGF1 after plasma activation had the greatest regeneration capacity and functional recovery in the experimental animals. When the above conduit was seeded with aligned neural stem cells, the efficacy was further enhanced and it approached that of the autograft group. This work suggested that microporous/micropatterned nerve conduits containing bioactive growth factors may be successfully fabricated by micropatterning techniques, open plasma activation, and immobilization, which, combined with aligned stem cells, may synergistically contribute to the regeneration of the severely damaged peripheral nerve. (paper)

  17. Evaluation of Na+/K+ pump function following repetitive activity in mouse peripheral nerve

    DEFF Research Database (Denmark)

    Moldovan, Mihai; Krarup, Christian

    2006-01-01

    After conduction of prolonged trains of impulses the increased Na+/K+ pump activity leads to hyperpolarization. The aim of this study was to develop a mouse model to investigate the Na+/K+ pump function in peripheral nerve by measuring the decrease in excitability during activity......-dependent hyperpolarization. Acute electrophysiological investigations were carried out in seven adult mice. Nerve excitability was evaluated by tracking the change in threshold current after 5 min of 100 Hz stimulation of the tibial nerve at ankle. We developed a threshold tracking system that allowed us to follow several...... excitability measures simultaneously from the evoked plantar compound muscle action potential (CMAP) and sciatic compound nerve action potential (CNAP). Three minutes after repetitive supramaximal stimulation maximal CMAP and CNAP amplitudes recovered but the threshold was increased approximately 40% for motor...

  18. Liquiritin potentiate neurite outgrowth induced by nerve growth factor in PC12 cells

    OpenAIRE

    Chen, Zheng-ai; Wang, Jun-Long; Liu, Rui-Ting; Ren, Jian-Ping; Wen, Li-Qing; Chen, Xiao-juan; Bian, Guang-Xing

    2009-01-01

    Neurite outgrowth and neuronal differentiation play a crucial role in the development of the nervous system. Understanding of neurotrophins induced neurite outgrowth was important to develop therapeutic strategy for axon regeneration in neurodegenerative diseases as well as after various nerve injuries. It has been reported that extension of neurite and differentiation of sympathetic neuron-like phenotype was modulated by nerve growth factor (NGF) in PC12 cells. In this study, NGF mediated ne...

  19. [Changes in neuropeptide Y and substance P immunoreactive nerve fibres and immunocompetent cells in hepatitis].

    Science.gov (United States)

    Fehér, Erzsébet

    2015-11-22

    Neuropeptide Y and substance P were thought to play a role in the function of immune cells and in amplification or elimination of the inflammatory processes. In hepatitis the number of both neuropeptide Y and substance P immunoreactive nerve fibres are increased, where the increase of neoropeptide Y is significant. A large number of lymphocytes and mast cells are also stained for neuropeptide Y and substance P. Very close associations (less than 1 µm) were observed between neuropeptide Y immunoreactive nerve fibres and immune cells stained also with neuropeptide Y. Some immune cells were also found to be immunoreactive for tumor necrosis factor-α and NF-κB. Some of the SP IR immunocells were also stained for TNF-α and nuclear factor kappaB. Based on these data it is hypothesized that neuropeptid Y and substance P released from nerve fibres and immune cells play a role in inflammation and elimination of inflammation in hepatitis.

  20. Bone Marrow-Derived, Neural-Like Cells Have the Characteristics of Neurons to Protect the Peripheral Nerve in Microenvironment

    OpenAIRE

    Shi-lei Guo; Zhi-ying Zhang; Yan Xu; Yun-xia Zhi; Chang-jie Han; Yu-hao Zhou; Fang Liu; Hai-yan Lin; Chuan-sen Zhang

    2015-01-01

    Effective repair of peripheral nerve defects is difficult because of the slow growth of new axonal growth. We propose that “neural-like cells” may be useful for the protection of peripheral nerve destructions. Such cells should prolong the time for the disintegration of spinal nerves, reduce lesions, and improve recovery. But the mechanism of neural-like cells in the peripheral nerve is still unclear. In this study, bone marrow-derived neural-like cells were used as seed cells. The cells were...

  1. Nerve injury induces glial cell line-derived neurotrophic factor (GDNF) expression in Schwann cells through purinergic signaling and the PKC-PKD pathway.

    Science.gov (United States)

    Xu, Pin; Rosen, Kenneth M; Hedstrom, Kristian; Rey, Osvaldo; Guha, Sushovan; Hart, Courtney; Corfas, Gabriel

    2013-07-01

    Upon peripheral nerve injury, specific molecular events, including increases in the expression of selected neurotrophic factors, are initiated to prepare the tissue for regeneration. However, the mechanisms underlying these events and the nature of the cells involved are poorly understood. We used the injury-induced upregulation of glial cell-derived neurotrophic factor (GDNF) expression as a tool to gain insights into these processes. We found that both myelinating and nonmyelinating Schwann cells are responsible for the dramatic increase in GDNF expression after injury. We also demonstrate that the GDNF upregulation is mediated by a signaling cascade involving activation of Schwann cell purinergic receptors, followed by protein kinase C signaling which activates protein kinase D (PKD), which leads to increased GDNF transcription. Given the potent effects of GDNF on survival and repair of injured peripheral neurons, we propose that targeting these pathways may yield therapeutic tools to treat peripheral nerve injury and neuropathies.

  2. Electrophysiological study in the infraorbital nerve of the rat: Spontaneous and evoked activity

    Energy Technology Data Exchange (ETDEWEB)

    AlbarracIn, A L [Catedra de Neurociencias, Facultad de Medicina, Universidad Nacional de Tucuman, Av. Roca 2200, PC 4000 (Argentina); Farfan, F D [Departamento de BioingenierIa, FACET, Universidad Nacional de Tucuman, INSIBIO - CONICET, CC 327, PC 4000 (Argentina); Felice, C J [Departamento de BioingenierIa, FACET, Universidad Nacional de Tucuman, INSIBIO - CONICET, CC 327, PC 4000 (Argentina)

    2007-11-15

    In this work we present some studies in the afferent nerve of the rat vibrissae. Studies on spontaneous activity (SA) in this sensorial system are of long data. Nevertheless, SA recordings in the nerve of a single vibrissa have not been made until present. In this work, we use an algorithm based on signal decomposition with Continuous Wavelet Transform (CWT) to analyse the discharges of two nerves. The action potentials of both nerves were detected and the firing rates were calculated. These results suggest that the firing rate of one vibrissa innervation is low considering that this nerve contains hundred of fibers. In addition, we present preliminary studies suggesting important effects of the hair shaft length in the afferent discharge during the vibrissae movements. The experiments consisted in recording the nerve activity after the vibrissae were sectioned at two different levels. The results showed important differences in the signal energy contents. It suggests that the hair shaft length would produce a differential activation of the mechanoreceptors located in the vibrissae follicle.

  3. Electrophysiological study in the infraorbital nerve of the rat: Spontaneous and evoked activity

    Science.gov (United States)

    Albarracín, A. L.; Farfán, F. D.; Felice, C. J.

    2007-11-01

    In this work we present some studies in the afferent nerve of the rat vibrissae. Studies on spontaneous activity (SA) in this sensorial system are of long data. Nevertheless, SA recordings in the nerve of a single vibrissa have not been made until present. In this work, we use an algorithm based on signal decomposition with Continuous Wavelet Transform (CWT) to analyse the discharges of two nerves. The action potentials of both nerves were detected and the firing rates were calculated. These results suggest that the firing rate of one vibrissa innervation is low considering that this nerve contains hundred of fibers. In addition, we present preliminary studies suggesting important effects of the hair shaft length in the afferent discharge during the vibrissae movements. The experiments consisted in recording the nerve activity after the vibrissae were sectioned at two different levels. The results showed important differences in the signal energy contents. It suggests that the hair shaft length would produce a differential activation of the mechanoreceptors located in the vibrissae follicle.

  4. Effect on pancreatic beta cells and nerve cells by low let x-ray

    Energy Technology Data Exchange (ETDEWEB)

    Park, Kwang Hun [Dept. of Nuclear Medicine, Kyungbuk National University Hospital, Daegu (Korea, Republic of); Kim, Kgu Hwan [Dept. of Radiological Technology, Daegu health College, Daegu (Korea, Republic of)

    2014-03-15

    Cultured pancreatic beta cells and nerve cells, it is given normal condition of 10% FBS (fetal bovine serum), 11.1 mM glucose and hyperglycemia condition of 1% FBS, 30 mM glucose. For low LET X-ray irradiated with 0.5 Gy/hr dose-rate(total dose: 0.5 to 5 Gy). Survival rates were measured by MTT assay. When non irradiated, differentiated in the pancreatic beta cells experiment is hyperglycemia conditions survival rate compared to normal conditions survival rate seemed a small reduction. However increasing the total dose of X-ray, the survival rate of normal conditions decreased slightly compared to the survival rate of hyperglycemia conditions, the synergistic effect was drastically reduced. When non irradiated, undifferentiated in the nerve cells experiment is hyperglycemia conditions survival rate compared to normal conditions survival rate seemed a large reduction. As the cumulative dose of X-ray normal conditions and hyperglycemia were all relatively rapid cell death. But the rate of decreased survivals by almost parallel to the reduction proceed and it didn't show synergistic effect.

  5. Mesenchymal stem cells modified with nerve growth factor improve recovery of the inferior alveolar nerve after mandibular distraction osteogenesis in rabbits.

    Science.gov (United States)

    Wang, L; Zhao, Y; Cao, J; Yang, X; Lei, D

    2015-03-01

    Distraction osteogenesis is widely used in the treatment of bony deformities and defects. However, injury to the inferior alveolar nerve is a concern. Our aim was to investigate the feasibility of using lentiviral-mediated human nerve growth factor beta (hNGFβ) of the inferior alveolar nerve in mandibular distraction osteogenesis in rabbits. To achieve this, mesenchymal stem cells (MSC) from the bone marrow of rabbit mandibles were isolated and genetically engineered using recombinant lentiviral vector containing hNGFβ. Twenty New Zealand white rabbits underwent mandibular distraction osteogenesis, and 5 million MSC transduced with hNGFβ-vector or control vector were transplanted around the nerve in the gap where the bone had been fractured during the operation (n=10 in each group). After gradual distraction, samples of the nerve were harvested for histological and histomorphometric analysis. We found that the genetically engineered MSC transduced by the lentiviral vector were able to secrete hNGFβ at physiologically relevant concentrations as measured by ELISA. Histological examination of the nerve showed more regenerating nerve fibres and less myelin debris in the group in which hNGFβ-modified MSC had been implanted than in the control group. Histomorphometric analysis of the nerve showed increased density of myelinated fibres in the group in which hNGFβ-modified MSC had been implanted than in the control group. The data suggest that implantation of hNGFβ-modified MSC can accelerate the morphological recovery of the inferior alveolar nerve during mandibular distraction osteogenesis in rabbits. The use of lentiviral-mediated gene treatment to deliver hNGFβ through MSC may be a promising way of minimising injury to the nerve. PMID:25600702

  6. Mesenchymal stem cells modified with nerve growth factor improve recovery of the inferior alveolar nerve after mandibular distraction osteogenesis in rabbits.

    Science.gov (United States)

    Wang, L; Zhao, Y; Cao, J; Yang, X; Lei, D

    2015-03-01

    Distraction osteogenesis is widely used in the treatment of bony deformities and defects. However, injury to the inferior alveolar nerve is a concern. Our aim was to investigate the feasibility of using lentiviral-mediated human nerve growth factor beta (hNGFβ) of the inferior alveolar nerve in mandibular distraction osteogenesis in rabbits. To achieve this, mesenchymal stem cells (MSC) from the bone marrow of rabbit mandibles were isolated and genetically engineered using recombinant lentiviral vector containing hNGFβ. Twenty New Zealand white rabbits underwent mandibular distraction osteogenesis, and 5 million MSC transduced with hNGFβ-vector or control vector were transplanted around the nerve in the gap where the bone had been fractured during the operation (n=10 in each group). After gradual distraction, samples of the nerve were harvested for histological and histomorphometric analysis. We found that the genetically engineered MSC transduced by the lentiviral vector were able to secrete hNGFβ at physiologically relevant concentrations as measured by ELISA. Histological examination of the nerve showed more regenerating nerve fibres and less myelin debris in the group in which hNGFβ-modified MSC had been implanted than in the control group. Histomorphometric analysis of the nerve showed increased density of myelinated fibres in the group in which hNGFβ-modified MSC had been implanted than in the control group. The data suggest that implantation of hNGFβ-modified MSC can accelerate the morphological recovery of the inferior alveolar nerve during mandibular distraction osteogenesis in rabbits. The use of lentiviral-mediated gene treatment to deliver hNGFβ through MSC may be a promising way of minimising injury to the nerve.

  7. Effects of nerve growth factor on the expression of caspase-12 of nerve cells in cerebral ischemia/reperfusion area

    Institute of Scientific and Technical Information of China (English)

    Jiping Yang; Huaijun Liu; Ying Li; Yan Liu; Haiqing Yang

    2006-01-01

    BACKGROUND: Researches suggest that cascade reaction of cysteine protease mediated by caspase-12 can cause apoptosis after cerebral ischemia/reperfusion injury;however, nerve growth factor (NGF) can reduce apoptosis through inhibiting activation of that reaction.OBJECTTVE: To observe the effect of NGF on the expression of caspase-12 in brain tissue of rabbits with cerebral ischemia/reperfusion injury, and elucidate the protective mechanism of NGF on neural apoptosis induced by cerebral ischemia/reperfusion injury.DESIGN: Randomized controlled animal study.SETTING: Department of Image, Second Hospital, Hebei Medical University.MATERIALS: A total of 26 healthy New Zealand rabbits, of clean grade, aged 4.5-5 months, weighing (2.6±0.2) kg, were selected in this study. Reagents: NGF (Xiamen Beida Zhilu Biotechnology Co., Ltd.);caspase-12 (Santa Cruz Biotechnology Company, USA, clone number: SC-12395); caspase-3 (Santa Cruz Biotechnology Company, USA, clone number: SC-7272); biotin-antibody Ⅱ and ABC compound (Wuhan Boster Company); in situ end-labeling (ISEL, Beijing Zhongshan Company).METHODS: The experiment was carried out in the Laboratories of Nerve Molecule Image Science and Neurology of the Second Hospital of Hebei Medical University from May to August 2005. ① All animals were randomly divided into three groups. Ischemia/reperfusion (I/R) group (n=10): Left middle cerebral artery (MCA) was blocked for 2 hours and then blooded for 2 hours in order to establish focal cerebral ischemia/reperfusion models. Sham operation group (n=6): Cork was inserted with 3 cm in depth, and then pulled to common carotid artery. Other procedures were as the same as those in ischemia/reperfusion group.Treatment group (n=10): After modeling, 400 AU (16 μg/L) NGF was inserted into cerebral infarction focus sham operation group and at 3 days after reperfusion in other two groups. In addition, contents of caspase-12 and caspase-3 were measured with immunohistochemical technique; mean

  8. Nerve Regeneration Potential of Protocatechuic Acid in RSC96 Schwann Cells by Induction of Cellular Proliferation and Migration through IGF-IR-PI3K-Akt Signaling.

    Science.gov (United States)

    Ju, Da-Tong; Liao, Hung-En; Shibu, Marthandam Asokan; Ho, Tsung-Jung; Padma, Viswanadha Vijaya; Tsai, Fuu-Jen; Chung, Li-Chin; Day, Cecilia Hsuan; Lin, Chien-Chung; Huang, Chih-Yang

    2015-12-31

    Peripheral nerve injuries, caused by accidental trauma, acute compression or surgery, often result in temporary or life-long neuronal dysfunctions and inflict great economic or social burdens on the patients. Nerve cell proliferation is an essential process to restore injured nerves of adults. Schwann cells play a crucial role in endogenous repair of peripheral nerves due to their ability to proliferate, migrate and provide trophic support to axons via expression of various neurotrophic factors, such as the nerve growth factor (NGF), especially after nerve injury. Protocatechuic acid (PCA) is a dihydroxybenzoic acid, a type of phenolic acid, isolated from the kernels of Alpinia oxyphylla Miq (AOF), a traditional Chinese herbal medicine the fruits of which are widely used as a tonic, aphrodisiac, anti-salivation and anti-diarrheatic. This study investigated the molecular mechanisms by which PCA induces Schwann cell proliferation by activating IGF-IR-PI3K-Akt pathway. Treatment with PCA induces phosphorylation of the insulin-like growth factor-I (IGF-I)-mediated phosphatidylinositol 3 kinase/serine - threonine kinase (PI3K/Akt) pathway, and activates expression of cell nuclear antigen (PCNA) in a dose-dependent manner. Cell cycle analysis after 18 h of treatment showed that proliferation of the RSC96 cells was enhanced by PCA treatment. The PCA induced proliferation was accompanied by modulation in the expressions of cell cycle proteins cyclin D1, cyclin E and cyclin A. Knockdown of PI3K using small interfering RNA (siRNA) and inhibition of IGF-IR receptor resulted in the reduction in cell survival proteins. The results collectively showed that PCA treatment promoted cell proliferation and cell survival via IGF-I signaling. PMID:26717920

  9. Biological conduits combining bone marrow mesenchymal stem cells and extracellular matrix to treat long-segment sciatic nerve defects

    Directory of Open Access Journals (Sweden)

    Yang Wang

    2015-01-01

    Full Text Available The transplantation of polylactic glycolic acid conduits combining bone marrow mesenchymal stem cells and extracellular matrix gel for the repair of sciatic nerve injury is effective in some respects, but few data comparing the biomechanical factors related to the sciatic nerve are available. In the present study, rabbit models of 10-mm sciatic nerve defects were prepared. The rabbit models were repaired with autologous nerve, a polylactic glycolic acid conduit + bone marrow mesenchymal stem cells, or a polylactic glycolic acid conduit + bone marrow mesenchymal stem cells + extracellular matrix gel. After 24 weeks, mechanical testing was performed to determine the stress relaxation and creep parameters. Following sciatic nerve injury, the magnitudes of the stress decrease and strain increase at 7,200 seconds were largest in the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells + extracellular matrix gel group, followed by the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells group, and then the autologous nerve group. Hematoxylin-eosin staining demonstrated that compared with the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells group and the autologous nerve group, a more complete sciatic nerve regeneration was found, including good myelination, regularly arranged nerve fibers, and a completely degraded and resorbed conduit, in the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells + extracellular matrix gel group. These results indicate that bridging 10-mm sciatic nerve defects with a polylactic glycolic acid conduit + bone marrow mesenchymal stem cells + extracellular matrix gel construct increases the stress relaxation under a constant strain, reducing anastomotic tension. Large elongations under a constant physiological load can limit the anastomotic opening and shift, which is beneficial for the regeneration and functional reconstruction of sciatic nerve. Better

  10. Developmental Corneal Innervation: Interactions between Nerves and Specialized Apical Corneal Epithelial Cells

    OpenAIRE

    Kubilus, James K.; Linsenmayer, Thomas F.

    2010-01-01

    During developmental innervation of the chicken cornea, nerves interact with apical corneal epithelial cells to form synapse-like structures. In addition, these apical epithelial cells express class III β-tubulin, an isoform of β-tubulin generally thought to be neuron specific.

  11. Minocycline inhibits the production of the precursor form of nerve growth factor by retinal microglial cells

    Institute of Scientific and Technical Information of China (English)

    Xiaochun Yang; Xuanchu Duan

    2013-01-01

    A rat model of acute ocular hypertension was established by enhancing the perfusion of balanced salt solution in the anterior chamber of the right eye. Minocycline (90 mg/kg) was administered intraperitoneally into rats immediately after the operation for 3 consecutive days. Immunofluorescence, western blot assay and PCR detection revealed that the expression of the precursor form of nerve growth factor, nerve growth factor and the p75 neurotrophin receptor, and the mRNA expression of nerve growth factor and the p75 neurotrophin receptor, increased after acute ocular hypertension. The number of double-labeled CD11B- and precursor form of nerve growth factor-positive cells, glial fibrillary acidic protein- and p75 neurotrophin receptor-positive cells, glial fibrillary acidic protein- and caspase-3-positive cells in the retina markedly increased after acute ocular hypertension. The above-described expression decreased after minocycline treatment. These results suggested that minocycline inhibited the increased expression of the precursor form of nerve growth factor in microglia, the p75 neurotrophin receptor in astroglia, and protected cells from apoptosis.

  12. Nitric oxide modulates bladder afferent nerve activity in the in vitro urinary bladder–pelvic nerve preparation from rats with cyclophosphamide induced cystitis

    OpenAIRE

    Yu, Yongbei; de Groat, William C.

    2012-01-01

    Effects of a nitric oxide (NO) donor (SNAP), NO substrate (l-arginine), and NO synthase inhibitor (l-NAME) on bladder afferent nerve (BAN) activity were studied in an in vitro bladder–pelvic nerve preparation from untreated or cyclophosphamide (CYP) treated rats. Distension of the bladder induced phasic bladder contractions (PBC) that were accompanied by multiunit afferent firing. Intravesical administration of SNAP (2 mM) which did not change the amplitude of PBC significantly decreased peak...

  13. EFFECTS OF INTRAVENOUS FENTANYL ON SPONTANEOUS RENAL SYMPATHETIC NERVE ACTIVITY IN NORMAL AND VAGOTOMIZED RABBITS

    Institute of Scientific and Technical Information of China (English)

    Chen Wang; James G.Whitwam

    2004-01-01

    Objective To investigate the roles of sympathetic and vagus nerves in hypotension and bradycardia induced by fentanyl.Methods Fourteen rabbits were divided into 2 groups: normal and vagotomized rabbits. Rabbits were anesthetized,paralyzed, and artificial ventilated. Right renal sympathetic nerve was exposed and prepared for recording electrical activity.Fentanyl was injected intravenously in incremental doses of 1, 4, 15, 30, and 50 μg/kg at 10 minutes intervals.Results Fentanyl significantly reduced the spontaneous activity of renal sympathetic nerve, mean arterial pressure, and heart rate above a total dose of 20 μg/kg in both normal and vagotomized rabbits. However, normal rabbits spontaneous sympathetic nerve activity and mean arterial pressure were more depressed than vagotomized rabbits at total doses of 50 and 100 μg/kg. There were no significant difference in the reduction of heart rate between normal and vagotomized rabbits.Conclusion Fentanyl induction of bradycardia and hypotension in rabbits is mainly due to depression of sympathetic nerve activity.

  14. Tumour necrosis factor α enhances CCL2 and ICAM-1 expression in peripheral nerve microvascular endoneurial endothelial cells

    Directory of Open Access Journals (Sweden)

    Evan B. Stubbs

    2013-02-01

    Full Text Available Recruitment and trafficking of autoreactive leucocytes across the BNB (blood–nerve barrier is an early pathological insult in GBS (Guillain-Barré syndrome, an aggressive autoimmune disorder of the PNS (peripheral nervous system. Whereas the aetiology and pathogenesis of GBS remain unclear, pro-inflammatory cytokines, including TNFα (tumour necrosis factor α, are reported to be elevated early in the course of GBS and may initiate nerve injury by activating the BNB. Previously, we reported that disrupting leucocyte trafficking in vivo therapeutically attenuates the course of an established animal model of GBS. Here, PNMECs (peripheral nerve microvascular endothelial cells that form the BNB were harvested from rat sciatic nerves, immortalized by SV40 (simian virus 40 large T antigen transduction and subsequently challenged with TNFα. Relative changes in CCL2 (chemokine ligand 2 and ICAM-1 (intercellular adhesion molecule 1 expression were determined. We report that TNFα elicits marked dose- and time-dependent increases in CCL2 and ICAM-1 mRNA and protein content and promotes secretion of functional CCL2 from immortalized and primary PNMEC cultures. TNFα-mediated secretion of CCL2 promotes, in vitro, the transendothelial migration of CCR2-expressing THP-1 monocytes. Increased CCL2 and ICAM-1 expression in response to TNFα may facilitate recruitment and trafficking of autoreactive leucocytes across the BNB in autoimmune disorders, including GBS.

  15. Neuregulin facilitates nerve regeneration by speeding Schwann cell migration via ErbB2/3-dependent FAK pathway.

    Directory of Open Access Journals (Sweden)

    Hung-Ming Chang

    Full Text Available BACKGROUND: Adequate migration of Schwann cells (Sc is crucial for axon-guidance in the regenerative process after peripheral nerve injury (PNI. Considering neuregulin-erbB-FAK signaling is an essential pathway participating in the regulation of Sc migration during development, the present study is aimed to examine whether neuregulin would exert its beneficial effects on adult following PNI and further determine the potential changes of downstream pathway engaged in neuro-regeneration by both in vitro and in vivo approaches. METHODOLOGY AND PRINCIPAL FINDINGS: Cultured RSC96 cells treated with neuregulin were processed for erbB2/3 immunofluorescence and FAK immunoblotings. The potential effects of neuregulin on Sc were assessed by cell adherence, spreading, and migration assays. In order to evaluate the functional significance of neuregulin on neuro-regeneration, the in vivo model of PNI was performed by chronic end-to-side neurorrhaphy (ESN. In vitro studies indicated that after neuregulin incubation, erbB2/3 were not only expressed in cell membranes, but also distributed throughout the cytoplasm and nucleus of RSC96 cells. Activation of erbB2/3 was positively correlated with FAK phosphorylation. Neuregulin also increases Sc adherence, spreading, and migration by 127.2 ± 5.0%, 336.8 ± 3.0%, and 80.0 ± 5.7%, respectively. As for in vivo study, neuregulin significantly accelerates the speed of Sc migration and increases Sc expression in the distal stump of injured nerves. Retrograde labeling and compound muscle action potential recordings (CMAP also showed that neuregulin successfully facilitates nerve regeneration by eliciting noticeably larger CMAP and promoting quick re-innervation of target muscles. CONCLUSIONS: As neuregulin successfully improves axo-glial interaction by speeding Sc migration via the erbB2/3-FAK pathway, therapeutic use of neuregulin may thus serve as a promising strategy to facilitate the progress of nerve regeneration

  16. Uptake of 3H-thymidine by the receptor cell populations after injury of the sensory nerve fibres

    International Nuclear Information System (INIS)

    The material of the study was the skin from the beak of two-day ducklings. The investigation was carried out on the 2nd, 5th, 20th and 45th day after the crushing of the sensory nerve fibres entering the capsulated Herbst receptors. Twenty four hours before the biopsy, the ducklings were injected at 6 hours intervals with 3H-thymidine. The number of labelled index in the three cell pupulations, participating in the receptor development was determined. The cells of the subcapsular space of all control animals (with intacted suborbital nerves) have shown the highest labelled index. The index of the capsular perineural cells is about 12 times lower, while the labelled index of the Schwann receptor cells is about 10 times lower. Following the denervation, the labelled index in increasing and reaches its maximum on the 5th postoperative day. The Schwann receptor cells in comparison to the two other cell populations show the most significant deviation during the regeneration (45th day after the intervention). The investigations show that all three cell populations pass through a miotic cycle of innovation. The low labelled index of the Schwann receptors (1-2 labelled cells in 1000) is an indication of a high differentiation. One can assume that their regeneration takes place at the expense of the proper proliferation activity as well as of the differentiation of the Schwann cells from the distal section of the regenerating sensory nerve fibres. Taking into consideration the high labelled index of the other populations, it seems most probable that their regeneration takes place for the expense of their own cell populations. (A.B.)

  17. Lacrimal gland and perioptic nerve lesions due to Langerhans cell histiocytosis (2007: 9b)

    Energy Technology Data Exchange (ETDEWEB)

    Herman, M.; Demaerel, P.; Wilms, G. [University Hospitals Leuven, Department of Radiology, Leuven (Belgium); Gool, S. van [University Hospitals Leuven, Department of Pediactrics, Leuven (Belgium); Casteels, I. [University Hospitals Leuven, Department of Ophthalmology, Leuven (Belgium)

    2007-12-15

    We report a patient presenting with bilateral lacrimal gland involvement and perioptic nerve sheath lesions due to Langerhans cell histiocytosis (LCH) invasion. LCH is a rare multisystemic disease characterized by a clonal proliferation of Langerhans cells. All organs may be involved with a clinical spectrum ranging from a solitary bone lesion to a severe life-threatening multisystem disease. Osteolytic orbital bone lesions with extension into the adjacent orbital soft tissues have been described. To our knowledge, lacrimal gland involvement has probably been described only once before. Perioptic nerve lesions are also very rare, having been described only three times before. (orig.)

  18. Lacrimal gland and perioptic nerve lesions due to Langerhans cell histiocytosis (2007: 9b)

    International Nuclear Information System (INIS)

    We report a patient presenting with bilateral lacrimal gland involvement and perioptic nerve sheath lesions due to Langerhans cell histiocytosis (LCH) invasion. LCH is a rare multisystemic disease characterized by a clonal proliferation of Langerhans cells. All organs may be involved with a clinical spectrum ranging from a solitary bone lesion to a severe life-threatening multisystem disease. Osteolytic orbital bone lesions with extension into the adjacent orbital soft tissues have been described. To our knowledge, lacrimal gland involvement has probably been described only once before. Perioptic nerve lesions are also very rare, having been described only three times before. (orig.)

  19. Nerve Growth Factor Modulate Proliferation of Cultured Rabbit Corneal Endothelial Cells and Epithelial Cells

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    In order to investigate the effect of nerve growth factor (NGF) on the proliferation of rabbit corneal endothelial cells and epithelial cells, the in vitro cultured rabbit corneal endothelial cells and epithelial cells were treated with different concentrations of NGF.MTT assay was used to examine the clonal growth and proliferation of the cells by determining the absorbency values at 570nm. The results showed that NGF with three concentrations ranging from 5 U/mL to 500 U/mL enhanced the proliferation of rabbit corneal endothelial cells in a concentration-dependent manner.50 U/mL and 500 U/mL NGF got more increase of proliferation than that of 5 U/mL NGF did.Meanwhile, 50 U/mL and 500 U/mL NGF could promote the proliferation of the rabbit corneal epithelial cells significantly in a concentration-dependent manner. However, 5 U/mL NGF did not enhance the proliferation of epithelial cells. It was suggested that exogenous NGF can stimulate the proliferation of both rabbit corneal endothelial and epithelial cells, but the extent of modulation is different.

  20. Human umbilical cord Wharton's Jelly-derived mesenchymal stem cells differentiation into nerve-like cells

    Institute of Scientific and Technical Information of China (English)

    MA Lian; FENG Xue-yong; CUI Bing-lin; Frieda Law; JIANG Xue-wu; YANG Li-ye; XIE Qing-dong; HUANG Tian-hua

    2005-01-01

    Background The two most basic properties of mesenchymal stem cells (MSCs) are the capacities to self-renew indefinitely and differentiate into multiple cells and tissue types. The cells from human umbilical cord Wharton's Jelly have properties of MSCs and represent a rich source of primitive cells. This study was conducted to explore the possibility of inducing human umbilical cord Wharton's Jelly-derived MSCs to differentiate into nerve-like cells.Methods MSCs were cultured from the Wharton's Jelly taken from human umbilical cord of babies delivered after full-term normal labor. Salvia miltiorrhiza and β-mercaptoethanol were used to induce the human umbilical cord-derived MSCs to differentiate. The expression of neural protein markers was shown by immunocytochemistry. The induction process was monitored by phase contrast microscopy, electron microscopy (EM), and laser scanning confocal microscopy (LSCM) .The pleiotrophin and nestin genes were measured by reverse transcription-polymerase chain reaction (RT-PCR). Results MSCs in the Wharton's Jelly were easily attainable and could be maintained and expanded in culture. They were positive for markers of MSCs, but negative for markers of hematopoietic cells and graft-versus-host disease (GVHD)-related cells. Treatment with Salvia miltiorrhiza caused Wharton's Jelly cells to undergo profound morphological changes. The induced MSCs developed rounded cell bodies with multiple neurite-like extensions. Eventually they developed processes that formed networks reminiscent of primary cultures of neurons. Salvia miltiorrhiza and β-mercaptoethanol also induced MSCs to express nestin, β-tubulinⅢ, neurofilament (NF) and glial fibrillary acidic protein (GFAP). It was confirmed by RT-PCR that MSCs could express pleiotrophin both before and after induction by Salvia miltiorrhiza. The expression was markedly enhanced after induction and the nestin gene was also expressed.Conclusions MSCs could be isolated from human umbilical

  1. Codonopsis pilosula (Franch) Nannftotal alkaloids potentiate neurite outgrowth induced by nerve growth factor in PC12 cells

    Institute of Scientific and Technical Information of China (English)

    LIUJian-Hui; BAOYong-Ming; SONGJi-Jun; ANLi-Jia

    2003-01-01

    AIM:To explore the effect of Codonopsis pilosula (Franch) Nannf total alkaloids (DSA) on differentiation inducedby nerve growth factor (NGF) in PC12 cells. METHODS: After culturing PC12 cells with DSA in the presence orabsence of NGF, neurite outgrowth in PC12 cells and correlated protein kinases were assayed. RESULTS: DSAalone did not exhibit neuritogenic activity, but caused a significant enhancement of NGF (2 μg/L)-induced neuriteoutgrowth in PC12 cells, and increased the phosphorylation of mitogen-activated protein kinase (MAPK).Furthermore, this enhancing effect was completely blocked by a specific MAPK kinase inhibitor, PD98059.CONCLUSION: DSA enhanced the NGF-induced neurite outgrowth in PC12 cells by amplifying an up-streamstep of the MAPK-dependent signaling pathway.

  2. The neurotoxic effects of hydrogen peroxide and copper in Retzius nerve cells of the leech Haemopis sanguisuga.

    Science.gov (United States)

    Jovanovic, Zorica D; Stanojevic, Marija B; Nedeljkov, Vladimir B

    2016-01-01

    Oxidative stress and the generation of reactive oxygen species (ROS) play an important role in cellular damage. Electrophysiological analyses have shown that membrane transport proteins are susceptible to ROS. In the present study, oxidative stress was induced in Retzius nerve cells of the leechHaemopis sanguisugaby bath application of 1 mM of hydrogen peroxide (H2O2) and 0.02 mM of copper (Cu) for 20 min. The H2O2/Cu(II) produced considerable changes in the electrical properties of the Retzius nerve cells. Intracellular recording of the resting membrane potential revealed that the neuronal membrane was depolarized in the presence of H2O2/Cu(II). We found that the amplitude of action potentials decreased, while the duration augmented in a progressive way along the drug exposure time. The combined application of H2O2and Cu(II) caused an initial excitation followed by depression of the spontaneous electrical activity. Voltage-clamp recordings revealed a second effect of the oxidant, a powerful inhibition of the outward potassium channels responsible for the repolarization of action potentials. The neurotoxic effect of H2O2/Cu(II) on the spontaneous spike electrogenesis and outward K(+)current of Retzius nerve cells was reduced in the presence of hydroxyl radical scavengers, dimethylthiourea and dimethyl sulfoxide, but not mannitol. This study provides evidence for the oxidative modification of outward potassium channels in Retzius nerve cells. The oxidative mechanism of the H2O2/Cu(II) system action on the electrical properties of Retzius neurons proposed in this study might have a wider significance, referring not only to leeches but also to mammalian neurons. PMID:26935393

  3. The neurotoxic effects of hydrogen peroxide and copper in Retzius nerve cells of the leech Haemopis sanguisuga

    Directory of Open Access Journals (Sweden)

    Zorica D. Jovanovic

    2016-04-01

    Full Text Available Oxidative stress and the generation of reactive oxygen species (ROS play an important role in cellular damage. Electrophysiological analyses have shown that membrane transport proteins are susceptible to ROS. In the present study, oxidative stress was induced in Retzius nerve cells of the leech Haemopis sanguisuga by bath application of 1 mM of hydrogen peroxide (H2O2 and 0.02 mM of copper (Cu for 20 min. The H2O2/Cu(II produced considerable changes in the electrical properties of the Retzius nerve cells. Intracellular recording of the resting membrane potential revealed that the neuronal membrane was depolarized in the presence of H2O2/Cu(II. We found that the amplitude of action potentials decreased, while the duration augmented in a progressive way along the drug exposure time. The combined application of H2O2 and Cu(II caused an initial excitation followed by depression of the spontaneous electrical activity. Voltage-clamp recordings revealed a second effect of the oxidant, a powerful inhibition of the outward potassium channels responsible for the repolarization of action potentials. The neurotoxic effect of H2O2/Cu(II on the spontaneous spike electrogenesis and outward K+ current of Retzius nerve cells was reduced in the presence of hydroxyl radical scavengers, dimethylthiourea and dimethyl sulfoxide, but not mannitol. This study provides evidence for the oxidative modification of outward potassium channels in Retzius nerve cells. The oxidative mechanism of the H2O2/Cu(II system action on the electrical properties of Retzius neurons proposed in this study might have a wider significance, referring not only to leeches but also to mammalian neurons.

  4. Expression and Purification of Active Recombinant Human Nerve Growth Factor from Escherichia coli

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Introduction Nerve growth factor (NGF) was first discovered and purified by Rita Levi-Montalcini and Stanley Cohen in the 1950s[1,2]. It represents the first cellular growth factor ever discovered and involved in the growth, survival, and differentiation of specific nerve cell populations[3]. Although animal tests and phase-Ⅱ clinical trials indicate that rhNGF could be an effective treatment for diabetic[4] and HIV-related neuropathies[5] , a large-scale phase-Ⅲ clinical trial has failed to give similar result[6].

  5. Bone marrow-derived, neural-like cells have the characteristics of neurons to protect the peripheral nerve in microenvironment.

    Science.gov (United States)

    Guo, Shi-Lei; Zhang, Zhi-Ying; Xu, Yan; Zhi, Yun-Xia; Han, Chang-Jie; Zhou, Yu-Hao; Liu, Fang; Lin, Hai-Yan; Zhang, Chuan-Sen

    2015-01-01

    Effective repair of peripheral nerve defects is difficult because of the slow growth of new axonal growth. We propose that "neural-like cells" may be useful for the protection of peripheral nerve destructions. Such cells should prolong the time for the disintegration of spinal nerves, reduce lesions, and improve recovery. But the mechanism of neural-like cells in the peripheral nerve is still unclear. In this study, bone marrow-derived neural-like cells were used as seed cells. The cells were injected into the distal end of severed rabbit peripheral nerves that were no longer integrated with the central nervous system. Electromyography (EMG), immunohistochemistry, and transmission electron microscopy (TEM) were employed to analyze the development of the cells in the peripheral nerve environment. The CMAP amplitude appeared during the 5th week following surgery, at which time morphological characteristics of myelinated nerve fiber formation were observed. Bone marrow-derived neural-like cells could protect the disintegration and destruction of the injured peripheral nerve. PMID:25861281

  6. Human umbilical cord mesenchymal stem cells promote peripheral nerve repair via paracrine mechanisms

    Directory of Open Access Journals (Sweden)

    Zhi-yuan Guo

    2015-01-01

    Full Text Available Human umbilical cord-derived mesenchymal stem cells (hUCMSCs represent a promising young-state stem cell source for cell-based therapy. hUCMSC transplantation into the transected sciatic nerve promotes axonal regeneration and functional recovery. To further clarify the paracrine effects of hUCMSCs on nerve regeneration, we performed human cytokine antibody array analysis, which revealed that hUCMSCs express 14 important neurotrophic factors. Enzyme-linked immunosorbent assay and immunohistochemistry showed that brain-derived neurotrophic factor, glial-derived neurotrophic factor, hepatocyte growth factor, neurotrophin-3, basic fibroblast growth factor, type I collagen, fibronectin and laminin were highly expressed. Treatment with hUCMSC-conditioned medium enhanced Schwann cell viability and proliferation, increased nerve growth factor and brain-derived neurotrophic factor expression in Schwann cells, and enhanced neurite growth from dorsal root ganglion explants. These findings suggest that paracrine action may be a key mechanism underlying the effects of hUCMSCs in peripheral nerve repair.

  7. Human umbilical cord mesenchymal stem cells promote peripheral nerve repairvia paracrine mechanisms

    Institute of Scientific and Technical Information of China (English)

    Zhi-yuan Guo; Xun Sun; Xiao-long Xu; Qing Zhao; Jiang Peng; Yu Wang

    2015-01-01

    Human umbilical cord-derived mesenchymal stem cells (hUCMSCs) represent a promising young-state stem cell source for cell-based therapy. hUCMSC transplantation into the transected sciatic nerve promotes axonal regeneration and functional recovery. To further clarify the para-crine effects of hUCMSCs on nerve regeneration, we performed human cytokine antibody array analysis, which revealed that hUCMSCs express 14 important neurotrophic factors. Enzyme-linked immunosorbent assay and immunohistochemistry showed that brain-derived neurotrophic factor, glial-derived neurotrophic factor, hepatocyte growth factor, neurotrophin-3, basic fibroblast growth factor, type I collagen, fibronectin and laminin were highly expressed. Treatment with hUCMSC-conditioned medium enhanced Schwann cell viability and proliferation, increased nerve growth factor and brain-derived neurotrophic factor expression in Schwann cells, and enhanced neurite growth from dorsal root ganglion explants. These ifndings suggest that paracrine action may be a key mechanism underlying the effects of hUCMSCs in peripheral nerve repair.

  8. A comparative study of axon-surrounding cells in the two nasal nerve tracts from mouse olfactory epithelium and vomeronasal organ.

    Science.gov (United States)

    Nakajima, Mitsunari; Tsuruta, Momoko; Mori, Hisamichi; Nishikawa, Chisa; Okuyama, Satoshi; Furukawa, Yoshiko

    2013-03-29

    The olfactory and vomeronasal systems are the two nasal chemical detectors in mammals. While glial cells in the olfactory nerve tracts have been well-investigated, little is known about cells in the vomeronasal nerve tracts. In the present study, we compared the expression patterns of marker proteins in the cells comprising the two nasal nerve tracts in mice. Neural crest-derived cells surrounded the olfactory nerve axons in the lamina propria of the olfactory epithelium. These cells expressed glial fibrillary acidic protein (GFAP) and p75 glycoprotein, which are markers of olfactory ensheathing cells. Neural crest-derived cells also surrounded the vomeronasal nerve axons in the lamina propria of the vomeronasal epithelium. These nerve axon-surrounding cells, however, did not express GFAP or p75. Rather, the vomeronasal nerve axons expressed GFAP and p75. These results suggest that axon-surrounding cells functionally differ between the olfactory and vomeronasal nerve tracts. PMID:23410787

  9. Mesenchymal stem cells engrafted in a fibrin scaffold stimulate Schwann cell reactivity and axonal regeneration following sciatic nerve tubulization.

    Science.gov (United States)

    Cartarozzi, Luciana P; Spejo, Aline B; Ferreira, Rui S; Barraviera, Benedito; Duek, Eliana; Carvalho, Juliana L; Góes, Alfredo M; Oliveira, Alexandre L R

    2015-03-01

    The present study investigated the effectiveness of mesenchymal stem cells (MSCs) associated with a fibrin scaffold (FS) for the peripheral regenerative process after nerve tubulization. Adult female Lewis rats received a unilateral sciatic nerve transection followed by repair with a polycaprolactone (PCL)-based tubular prosthesis. Sixty days after injury, the regenerated nerves were studied by immunohistochemistry. Anti-p75NTR immunostaining was used to investigate the reactivity of the MSCs. Basal labeling, which was upregulated during the regenerative process, was detected in uninjured nerves and was significantly greater in the MSC-treated group. The presence of GFP-positive MSCs was detected in the nerves, indicating the long term survival of such cells. Moreover, there was co-localization between MSCs and BNDF immunoreactivity, showing a possible mechanism by which MSCs improve the reactivity of SCs. Myelinated axon counting and morphometric analyses showed that MSC engrafting led to a higher degree of fiber compaction combined with a trend of increased myelin sheath thickness, when compared with other groups. The functional result of MSC engrafting was that the animals showed higher motor function recovery at the seventh and eighth week after lesion. The findings herein show that MSC+FS therapy improves the nerve regeneration process by positively modulating the reactivity of SCs. PMID:25602253

  10. Bone Marrow-Derived, Neural-Like Cells Have the Characteristics of Neurons to Protect the Peripheral Nerve in Microenvironment

    Directory of Open Access Journals (Sweden)

    Shi-lei Guo

    2015-01-01

    Full Text Available Effective repair of peripheral nerve defects is difficult because of the slow growth of new axonal growth. We propose that “neural-like cells” may be useful for the protection of peripheral nerve destructions. Such cells should prolong the time for the disintegration of spinal nerves, reduce lesions, and improve recovery. But the mechanism of neural-like cells in the peripheral nerve is still unclear. In this study, bone marrow-derived neural-like cells were used as seed cells. The cells were injected into the distal end of severed rabbit peripheral nerves that were no longer integrated with the central nervous system. Electromyography (EMG, immunohistochemistry, and transmission electron microscopy (TEM were employed to analyze the development of the cells in the peripheral nerve environment. The CMAP amplitude appeared during the 5th week following surgery, at which time morphological characteristics of myelinated nerve fiber formation were observed. Bone marrow-derived neural-like cells could protect the disintegration and destruction of the injured peripheral nerve.

  11. MODULATION BREATHING OF THE ELECTRICAL ACTIVITY IN THE PHRENIC NERVE DURING STARTLES REFLEXES

    OpenAIRE

    Emanov, Sergey

    2006-01-01

    In the paper the reflex activity in the phrenic nerve is studied in chloralose anesthetized cats during development of somatic startle reflexes. Modulation of responses during the respiratory cycle is described. Organization of possible neurophysiologic mechanisms of phrenic responses during startle reflexes is discussed

  12. Vagus nerve stimulation inhibits activation of coagulation and fibrinolysis during endotoxemia in rats

    NARCIS (Netherlands)

    D.J. van Westerloo; I.A. Giebelen; J.C.M. Meijers; J. Daalhuisen; A.F. de Vos; M. Levi; T. van der Poll

    2006-01-01

    Background: Sepsis and endotoxemia are associated with concurrent activation of inflammation and the hemostatic mechanism, which both contribute to organ dysfunction and death. Electrical vagus nerve stimulation (VNS) has been found to inhibit tumor necrosis factor (TNF)-alpha release during endotox

  13. Effect of glial cell line-derived neurotrophic factor on peripheral nerve regeneration in adult rat

    Institute of Scientific and Technical Information of China (English)

    CHEN Zhe-yu; LI Jian-hong; ZHENG Xing-dong; LU Chang-lin; HE Cheng

    2001-01-01

    Objective: To study the effect of glial cell line-derived neurotrophic (GDNF) on adult peripheral nerve regeneration. Methods: Transectioned sciatic nerve in adult rats was sutured into silicone channel. GDNF or SAL solution was injected into the silicone channels during operation. Four weeks later, the effect of GDNF on axonal regeneration was evaluated by degenerative neurofiber staining and HRP retrograde tracing. Results: Compared with SAL group, the percentage of degenerative neurofiber areas decreased from 17.3% to 1.9% ( P<0.01 ) and the ratio of labeled spinal somas number was significantly increased from 43.5% to 68.3% ( P<0.01 ) in GDNF group. Conclusion: The results suggest that exogenous GDNF can obviously enhance adult peripheral nerve regeneration.

  14. Stimulation of raphe (obscurus) nucleus causes long-term potentiation of phrenic nerve activity in cat.

    Science.gov (United States)

    Millhorn, D E

    1986-12-01

    1. The respiratory response, measured as integrated phrenic nerve activity, during and for up to an hour following 10 min of continuous electrical stimulation of raphe obscurus was quantitated in anaesthetized, artificially ventilated cats whose carotid sinus nerves and vagus nerves had been cut. End-tidal PCO2 and body temperature were kept constant with servocontrollers. 2. Stimulation of raphe obscurus caused a significant increase in both phrenic tidal activity and respiratory frequency that persisted following cessation of the stimulus. This persistent facilitation is referred to as 'long-term potentiation' of respiration. 3. Control stimulations in the parenchyma of the medulla oblongata failed to stimulate respiration and cause the long-term potentiation. 4. Both the direct facilitatory effects of raphe obscurus stimulation on phrenic nerve activity and the long-term potentiation of respiration following the stimulus were prevented by pre-treating cats with methysergide, a serotonin receptor antagonist. 5. The results are discussed in terms of the raphe obscurus being the potential source of the long-term potentiation of respiration that occurs following stimulation of carotid body afferents (Millhorn, Eldridge & Waldrop, 1980a, b). PMID:3114470

  15. Malignant Trigeminal Nerve Sheath Tumor and Anaplastic Astrocytoma Collision Tumor with High Proliferative Activity and Tumor Suppressor P53 Expression

    Directory of Open Access Journals (Sweden)

    Maher Kurdi

    2014-01-01

    Full Text Available Background. The synchronous development of two primary brain tumors of distinct cell of origin in close proximity or in contact with each other is extremely rare. We present the first case of collision tumor with two histological distinct tumors. Case Presentation. A 54-year-old woman presented with progressive atypical left facial pain and numbness for 8 months. MRI of the brain showed left middle cranial fossa heterogeneous mass extending into the infratemporal fossa. At surgery, a distinct but intermingled intra- and extradural tumor was demonstrated which was completely removed through left orbitozygomatic-temporal craniotomy. Histopathological examination showed that the tumor had two distinct components: malignant nerve sheath tumor of the trigeminal nerve and temporal lobe anaplastic astrocytoma. Proliferative activity and expressed tumor protein 53 (TP53 gene mutations were demonstrated in both tumors. Conclusions. We describe the first case of malignant trigeminal nerve sheath tumor (MTNST and anaplastic astrocytoma in collision and discuss the possible hypothesis of this rare occurrence. We propose that MTNST, with TP53 mutation, have participated in the formation of anaplastic astrocytoma, or vice versa.

  16. Hirschsprung's disease: Is there a relationship between mast cells and nerve fibers?

    Institute of Scientific and Technical Information of China (English)

    Amit Kumar Yadav; Kiran Mishra; Anup Mohta; Sarla Agarwal

    2009-01-01

    AIM:To define the topography of mast cells and their numbers in cases of Hirschsprung's disease (HD) and non-HD, assess neural hypertrophy using imaging software and to study the relationship between mast cells and nerve fibers. METHODS:HE stained sections of 32 cases of chronic constipation in the age group of 0-14 years were reviewed for ganglion cells. AChE staining was performed on frozen sections of colonic and rectal biopsies. Based on their findings cases were divided into HD and non-HD and mast cells stained by toluidine blue were evaluated. Image analysis by computerized software was applied to S-100 stained sections for assessment of neural hypertrophy. RESULTS:Difference between number of mast cells in HD group (mean = 36.44) and in non-HD group (mean = 14.79) was statistically significant. Image analysis morphometry on S-100 stained sections served as a useful adjunct. The difference between number, size, and perimeter of the nerve fibers between HD and non-HD group was statistically significant. CONCLUSION:Mast cells are significantly increased in HD and their base line values are much higher in Indian children than that reported in Western literature. Their role in HD needs further research. Morphometry of S-100 stained nerve fibers is a useful adjunct to conventional methods for diagnosis of HD.

  17. Advantage of recording single-unit muscle sympathetic nerve activity in heart failure

    Directory of Open Access Journals (Sweden)

    HISAYOSHI eMURAI

    2012-05-01

    Full Text Available Elevated sympathetic activation is a characteristic feature of heart failure (HF. Excessive sympathetic activation under resting conditions has been shown to increase from the early stages of the disease, and is related to prognosis. Direct recording of multiunit efferent muscle sympathetic nerve activity (MSNA by microneurography is the best method for quantifying sympathetic nerve activity in humans. To date, this technique has been used to evaluate the actual central sympathetic outflow to the periphery in HF patients at rest and during exercise; however, because the firing occurrence of sympathetic activation is mainly synchronized by pulse pressure, multiunit MSNA, expressed as burst frequency (bursts/min and burst incidence (bursts/100heartbeats, may have limitations for the quantification of sympathetic nerve activity. In HF, multiunit MSNA is near the maximum level, and cannot increase further than the heartbeat. Single-unit MSNA analysis in humans is technically demanding, but provides more detailed information regarding central sympathetic firing. Although a great deal is known about the response of multiunit MSNA to stress, little information is available regarding the responses of single-unit MSNA to physiological stress and disease. The purposes of this review are to describe the differences between multiunit and single-unit MSNA during stress and to discuss the advantages of single-unit MSNA recording in improving our understanding the pathology of increased sympathetic activity in HF.

  18. Leptin-Induced Sympathetic Nerve Activation: Signaling Mechanisms and Cardiovascular Consequences in Obesity

    OpenAIRE

    Rahmouni, Kamal

    2010-01-01

    Obesity increases cardiovascular morbidity and mortality in part by inducing hypertension. One factor linking excess fat mass to cardiovascular diseases may be the sympathetic cardiovascular actions of leptin. Initial studies of leptin showed it regulates appetite and enhances energy expenditure by activating sympathetic nerve activity (SNA) to thermogenic brown adipose tissue. Further study, however, demonstrated leptin also causes sympathetic excitation to the kidney that, in turn, increase...

  19. Protein gene product 9.5-immunoreactive nerve fibres and cells in human skin.

    Science.gov (United States)

    Wang, L; Hilliges, M; Jernberg, T; Wiegleb-Edström, D; Johansson, O

    1990-07-01

    Sections of human skin were processed according to the indirect immunofluorescence technique with a rabbit antiserum against human protein gene product 9.5 (PGP 9.5). Immunoreactivity was detected in intraepidermal and dermal nerve fibres and cells. The intraepidermal nerves were varicose or smooth with different diameters, running as single processes or branched, straight or bent, projecting in various directions and terminating in the stratum basale, spinosum or granulosum. The density of the intraepidermal nerves varied between the different skin areas investigated. PGP 9.5-containing axons of the lower dermis were found in large bundles. They separated into smaller axon bundles within the upper dermis, entering this portion of the skin perpendicular to the surface. Then they branched into fibres mainly arranged parallel to the epidermal-dermal junctional zone. However, the fibres en route to the epidermis traversed the upper dermis more or less perpendicularly. Furthermore, immunoreactive dermal nerve fibres were found in the Meissner corpuscles, the arrector pili muscles, hair follicles, around the eccrine and apocrine sweat glands and around certain blood vessels. Such fibres were also observed around most subcutaneous blood vessels, sometimes heavily innervating these structures. Numerous weakly-to-strongly PGP 9.5-immunoreactive cells were found both in the epidermis and in the dermis. PMID:2143435

  20. Real-time detection of dopamine released from a nerve model cell by an enzyme-catalyzed luminescence method and its application to drug assessment.

    Science.gov (United States)

    Shinohara, Hiroaki; Wang, Feifei

    2007-01-01

    A real-time observation of neurotransmitter release from a nerve cell is a useful method for not only neuroscience research, but also assessing of the influence of chemicals, including drugs, on the human nervous system. In this study, a more simple and sensitive method for real-time monitoring of dopamine release from a nerve model cell was developed. Highly sensitive detection of dopamine was performed by using tyramine oxidase for dopamine oxidation, which was followed by a luminol luminescence reaction. This enzyme-catalyzed luminescence method was applied to observe dopamine release from the PC12 cell as a nerve model cell upon stimulation with acetylcholine and an acetylcholine receptor agonist. The results demonstrated that the real-time monitoring of the activation of the PC12 cell was easily performed by this method. This method possessed many advantages, such as high sensitivity, rapid measurement and no pretreatment for cells. It might be applied to drug screening and the assessment of harmful influences of food additives and pesticides on the nerves. PMID:17213629

  1. A combination of Schwann-cell grafts and aerobic exercise enhances sciatic nerve regeneration.

    Directory of Open Access Journals (Sweden)

    Camila Oliveira Goulart

    Full Text Available Despite the regenerative potential of the peripheral nervous system, severe nerve lesions lead to loss of target-organ innervation, making complete functional recovery a challenge. Few studies have given attention to combining different approaches in order to accelerate the regenerative process.Test the effectiveness of combining Schwann-cells transplantation into a biodegradable conduit, with treadmill training as a therapeutic strategy to improve the outcome of repair after mouse nerve injury.Sciatic nerve transection was performed in adult C57BL/6 mice; the proximal and distal stumps of the nerve were sutured into the conduit. Four groups were analyzed: acellular grafts (DMEM group, Schwann cell grafts (3×105/2 µL; SC group, treadmill training (TMT group, and treadmill training and Schwann cell grafts (TMT + SC group. Locomotor function was assessed weekly by Sciatic Function Index and Global Mobility Test. Animals were anesthetized after eight weeks and dissected for morphological analysis.Combined therapies improved nerve regeneration, and increased the number of myelinated fibers and myelin area compared to the DMEM group. Motor recovery was accelerated in the TMT + SC group, which showed significantly better values in sciatic function index and in global mobility test than in the other groups. The TMT + SC group showed increased levels of trophic-factor expression compared to DMEM, contributing to the better functional outcome observed in the former group. The number of neurons in L4 segments was significantly higher in the SC and TMT + SC groups when compared to DMEM group. Counts of dorsal root ganglion sensory neurons revealed that TMT group had a significant increased number of neurons compared to DMEM group, while the SC and TMT + SC groups had a slight but not significant increase in the total number of motor neurons.These data provide evidence that this combination of therapeutic strategies can significantly improve functional

  2. Brain-derived neurotrophic factor from bone marrow-derived cells promotes post-injury repair of peripheral nerve.

    Directory of Open Access Journals (Sweden)

    Yoshinori Takemura

    Full Text Available Brain-derived neurotrophic factor (BDNF stimulates peripheral nerve regeneration. However, the origin of BNDF and its precise effect on nerve repair have not been clarified. In this study, we examined the role of BDNF from bone marrow-derived cells (BMDCs in post-injury nerve repair. Control and heterozygote BDNF knockout mice (BDNF+/- received a left sciatic nerve crush using a cerebral blood clip. Especially, for the evaluation of BDNF from BMDCs, studies with bone marrow transplantation (BMT were performed before the injury. We evaluated nerve function using a rotarod test, sciatic function index (SFI, and motor nerve conduction velocity (MNCV simultaneously with histological nerve analyses by immunohistochemistry before and after the nerve injury until 8 weeks. BDNF production was examined by immunohistochemistry and mRNA analyses. After the nerve crush, the controls showed severe nerve dysfunction evaluated at 1 week. However, nerve function was gradually restored and reached normal levels by 8 weeks. By immunohistochemistry, BDNF expression was very faint before injury, but was dramatically increased after injury at 1 week in the distal segment from the crush site. BDNF expression was mainly co-localized with CD45 in BMDCs, which was further confirmed by the appearance of GFP-positive cells in the BMT study. Variant analysis of BDNF mRNA also confirmed this finding. BDNF+/- mice showed a loss of function with delayed histological recovery and BDNF+/+→BDNF+/- BMT mice showed complete recovery both functionally and histologically. These results suggested that the attenuated recovery of the BDNF+/- mice was rescued by the transplantation of BMCs and that BDNF from BMDCs has an essential role in nerve repair.

  3. The Use of Fiber-Reinforced Scaffolds Cocultured with Schwann Cells and Vascular Endothelial Cells to Repair Rabbit Sciatic Nerve Defect with Vascularization

    OpenAIRE

    Hongyang Gao; Yang You; Guoping Zhang; Feng Zhao; Ziyi Sha; Yong Shen

    2013-01-01

    To explore the feasibility of biodegradable fiber-reinforced 3D scaffolds with satisfactory mechanical properties for the repair of long-distance sciatic nerve defect in rabbits and effects of vascularized graft in early stage on the recovery of neurological function, Schwann cells and vascular endothelial cells were cocultured in the fiber-reinforced 3D scaffolds. Experiment group which used prevascularized nerve complex for the repair of sciatic nerve defect and control group which only cul...

  4. Nerve Growth Factor Gene Therapy Activates Neuronal Responses in Alzheimer’s Disease

    Science.gov (United States)

    Tuszynski, Mark H.; Yang, Jennifer H.; Barba, David; U, H S.; Bakay, Roy; Pay, Mary M.; Masliah, Eliezer; Conner, James M.; Kobalka, Peter; Roy, Subhojit; Nagahara, Alan H.

    2016-01-01

    IMPORTANCE Alzheimer’s disease (AD) is the most common neurodegenerative disorder, and lacks effective disease modifying therapies. In 2001 we initiated a clinical trial of Nerve Growth Factor (NGF) gene therapy in AD, the first effort at gene delivery in an adult neurodegenerative disorder. This program aimed to determine whether a nervous system growth factor prevents or reduces cholinergic neuronal degeneration in AD patients. We present post-mortem findings in 10 subjects with survival times ranging from 1 to 10 years post-treatment. OBJECTIVE To determine whether degenerating neurons in AD retain an ability to respond to a nervous system growth factor delivered after disease onset. DESIGN, SETTING, AND PARTICIPANTS 10 patients with early AD underwent NGF gene therapy using either ex vivo or in vivo gene transfer. The brains of all eight patients in the first Phase 1 ex vivo trial and two patients in a subsequent Phase 1 in vivo trial were examined. MAIN OUTCOME MEASURES Brains were immunolabeled to evaluate in vivo gene expression, cholinergic neuronal responses to NGF, and activation of NGF-related cell signaling. In two cases, NGF protein levels were measured by ELISA. RESULTS Degenerating neurons in the AD brain respond to NGF. All patients exhibited a trophic response to NGF, in the form of axonal sprouting toward the NGF source. Comparing treated and non-treated sides of the brain in three patients that underwent unilateral gene transfer, cholinergic neuronal hypertrophy occurred on the NGF-treated side (P>0.05). Activation of cellular signaling and functional markers were present in two patients that underwent AAV2-mediated NGF gene transfer. Neurons exhibiting tau pathology as well as neurons free of tau expressed NGF, indicating that degenerating cells can be infected with therapeutic genes with resulting activation of cell signaling. No adverse pathological effects related to NGF were observed. CONCLUSIONS AND RELEVANCE These findings indicate that

  5. Bone marrow cells produce nerve growth factor and promote angiogenesis around transplanted islets

    Institute of Scientific and Technical Information of China (English)

    Naoaki; Sakata; Nathaniel; K; Chan; John; Chrisler; Andre; Obenaus; Eba; Hathout

    2010-01-01

    AIM:To clarify the mechanism by which bone marrow cells promote angiogenesis around transplanted islets.METHODS: Streptozotocin induced diabetic BALB/ c mice were transplanted syngeneically under the kidney capsule with the following: (1) 200 islets (islet group: n=12), (2) 1-5×106 bone marrow cells (bone marrow group: n=11), (3) 200 islets and 1-5×106 bone marrow cells (islet + bone marrow group: n= 13), or (4) no cells (sham group:n=5). All mice were evaluated for blood glucose, serum insulin, serum nerve...

  6. Enhancing nerve regeneration in the peripheral nervous system using polymeric scaffolds, stem cell engineering and nanoparticle delivery system

    Science.gov (United States)

    Sharma, Anup Dutt

    Peripheral nerve regeneration is a complex biological process responsible for regrowth of neural tissue following a nerve injury. The main objective of this project was to enhance peripheral nerve regeneration using interdisciplinary approaches involving polymeric scaffolds, stem cell therapy, drug delivery and high content screening. Biocompatible and biodegradable polymeric materials such as poly (lactic acid) were used for engineering conduits with micropatterns capable of providing mechanical support and orientation to the regenerating axons and polyanhydrides for fabricating nano/microparticles for localized delivery of neurotrophic growth factors and cytokines at the site of injury. Transdifferentiated bone marrow stromal cells or mesenchymal stem cells (MSCs) were used as cellular replacements for lost native Schwann cells (SCs) at the injured nerve tissue. MSCs that have been transdifferentiated into an SC-like phenotype were tested as a substitute for the myelinating SCs. Also, genetically modified MSCs were engineered to hypersecrete brain- derived neurotrophic factor (BDNF) and glial cell line-derived neurotrophic factor (GDNF) to secrete therapeutic factors which Schwann cell secrete. To further enhance the regeneration, nerve growth factor (NGF) and interleukin-4 (IL4) releasing polyanhydrides nano/microparticles were fabricated and characterized in vitro for their efficacy. Synergistic use of these proposed techniques was used for fabricating a multifunctional nerve regeneration conduit which can be used as an efficient tool for enhancing peripheral nerve regeneration.

  7. Respiratory-related hypoglossal nerve activity: influence of anesthetics.

    Science.gov (United States)

    Hwang, J C; St John, W M; Bartlett, D

    1983-09-01

    In decerebrate, vagotomized, paralyzed, and ventilated cats, phrenic and respiratory-related hypoglossal discharges were evident at normocapnic normoxia or hyperoxia. Both increased progressively in hypercapnia or hypoxia. With increasing drive, onset of inspiratory hypoglossal activity began earlier relative to phrenic onset; an early expiratory hypoglossal burst was also observed. Following subanesthetic doses of chloralose, halothane, ketamine, or pentobarbital, hypoglossal activity was depressed much more than phrenic discharge. In moderate hypercapnia or hypoxia, phrenic activity increased more than hypoglossal, whereas, at high drive, the latter rose more sharply in some cats. Electromyograms of the diaphragm and genioglossus were recorded in intact awake cats to determine if their responses and those of decerebrates are comparable. Respiratory-related genioglossal discharge was evident in normocapnia. We conclude that anesthesia suppresses hypoglossal motor activities much more than those of the bulbospinal-phrenic system. Data for decerebrate cats and unanesthetized cats or humans provide no evidence of a differential distribution of chemoreceptor afferents on hypoglossal and bulbospinal-phrenic neurons, as suggested by results in anesthetized animals. PMID:6629915

  8. Real-Time Assessment of Autonomic Nerve Activity During Adaptive Servo-Ventilation Support or Waon Therapy.

    Science.gov (United States)

    Imamura, Teruhiko; Kinugawa, Koichiro; Nitta, Daisuke; Komuro, Issei

    2016-07-27

    Adaptive servo-ventilation support and Waon therapy are recently developed non-pharmacological and noninvasive therapies for patients with heart failure refractory to guideline-directed medical therapy. These therapies decrease both preload and afterload, increase cardiac output, and appear to ameliorate autonomic nerve activity. However, the time course of autonomic nerve activity during these therapies remains unclear. We performed heart rate variability analysis using the MemCalc power spectral density method (MemCalc system; Suwa Trust Co, Tokyo) to assess autonomic nerve activity during adaptive servo-ventilation support and Waon therapy in two different cases and determined the time course of autonomic nerve activity during these therapies. During both therapies, we found a drastic increase in parasympathetic nerve activity and continuous suppression of sympathetic nerve activity. Heart rate variability analysis using the MemCalc method may be promising for the assessment of the efficacy of various treatments, including adaptive servo-ventilation support and Waon therapy, from the viewpoint of autonomic nerve activity. PMID:27385607

  9. Current progress in use of adipose derived stem cells inperipheral nerve regeneration

    Institute of Scientific and Technical Information of China (English)

    Shomari DL Zack-Williams; Peter E Butler; Deepak M Kalaskar

    2015-01-01

    Unlike central nervous system neurons; those in theperipheral nervous system have the potential for fullregeneration after injury. Following injury, recovery iscontrolled by schwann cells which replicate and modulatethe subsequent immune response. The level of nerverecovery is strongly linked to the severity of the initialinjury despite the significant advancements in imagingand surgical techniques. Multiple experimental modelshave been used with varying successes to augment thenatural regenerative processes which occur following nerveinjury. Stem cell therapy in peripheral nerve injury maybe an important future intervention to improve the bestattainable clinical results. In particular adipose derivedstem cells (ADSCs) are multipotent mesenchymal stemcells similar to bone marrow derived stem cells, which arethought to have neurotrophic properties and the ability todifferentiate into multiple lineages. They are ubiquitouswithin adipose tissue; they can form many structuresresembling the mature adult peripheral nervous system.Following early in vitro work; multiple small and largeanimal in vivo models have been used in conjunction withconduits, autografts and allografts to successfully bridgethe peripheral nerve gap. Some of the ADSC relatedneuroprotective and regenerative properties have beenelucidated however much work remains before a modelcan be used successfully in human peripheral nerve injury(PNI). This review aims to provide a detailed overview ofprogress made in the use of ADSC in PNI, with discussionon the role of a tissue engineered approach for PNI repair.

  10. Cerebrospinal Fluid Hypernatremia Elevates Sympathetic Nerve Activity and Blood Pressure via the Rostral Ventrolateral Medulla.

    Science.gov (United States)

    Stocker, Sean D; Lang, Susan M; Simmonds, Sarah S; Wenner, Megan M; Farquhar, William B

    2015-12-01

    Elevated NaCl concentrations of the cerebrospinal fluid increase sympathetic nerve activity (SNA) in salt-sensitive hypertension. Neurons of the rostral ventrolateral medulla (RVLM) play a pivotal role in the regulation of SNA and receive mono- or polysynaptic inputs from several hypothalamic structures responsive to hypernatremia. Therefore, the present study investigated the contribution of RVLM neurons to the SNA and pressor response to cerebrospinal fluid hypernatremia. Lateral ventricle infusion of 0.15 mol/L, 0.6 mol/L, and 1.0 mol/L NaCl (5 µL/10 minutes) produced concentration-dependent increases in lumbar SNA, adrenal SNA, and arterial blood pressure, despite no change in splanchnic SNA and a decrease in renal SNA. Ganglionic blockade with chlorisondamine or acute lesion of the lamina terminalis blocked or significantly attenuated these responses, respectively. RVLM microinjection of the gamma-aminobutyric acid (GABAA) agonist muscimol abolished the sympathoexcitatory response to intracerebroventricular infusion of 1 mol/L NaCl. Furthermore, blockade of ionotropic glutamate, but not angiotensin II type 1, receptors significantly attenuated the increase in lumbar SNA, adrenal SNA, and arterial blood pressure. Finally, single-unit recordings of spinally projecting RVLM neurons revealed 3 distinct populations based on discharge responses to intracerebroventricular infusion of 1 mol/L NaCl: type I excited (46%; 11/24), type II inhibited (37%; 9/24), and type III no change (17%; 4/24). All neurons with slow conduction velocities were type I cells. Collectively, these findings suggest that acute increases in cerebrospinal fluid NaCl concentrations selectively activate a discrete population of RVLM neurons through glutamate receptor activation to increase SNA and arterial blood pressure. PMID:26416846

  11. Phosphatidylinositol 3-Kinase Couples Localised Calcium Influx to Activation of Akt in Central Nerve Terminals.

    Science.gov (United States)

    Nicholson-Fish, Jessica C; Cousin, Michael A; Smillie, Karen J

    2016-03-01

    The efficient retrieval of synaptic vesicle membrane and cargo in central nerve terminals is dependent on the efficient recruitment of a series of endocytosis modes by different patterns of neuronal activity. During intense neuronal activity the dominant endocytosis mode is activity-dependent endocytosis (ADBE). Triggering of ADBE is linked to calcineurin-mediated dynamin I dephosphorylation since the same stimulation intensities trigger both. Dynamin I dephosphorylation is maximised by a simultaneous inhibition of its kinase glycogen synthase kinase 3 (GSK3) by the protein kinase Akt, however it is unknown how increased neuronal activity is transduced into Akt activation. To address this question we determined how the activity-dependent increases in intracellular free calcium ([Ca(2+)]i) control activation of Akt. This was achieved using either trains of high frequency action potentials to evoke localised [Ca(2+)]i increases at active zones, or a calcium ionophore to raise [Ca(2+)]i uniformly across the nerve terminal. Through the use of either non-specific calcium channel antagonists or intracellular calcium chelators we found that Akt phosphorylation (and subsequent GSK3 phosphorylation) was dependent on localised [Ca(2+)]i increases at the active zone. In an attempt to determine mechanism, we antagonised either phosphatidylinositol 3-kinase (PI3K) or calmodulin. Activity-dependent phosphorylation of both Akt and GSK3 was arrested on inhibition of PI3K, but not calmodulin. Thus localised calcium influx in central nerve terminals activates PI3K via an unknown calcium sensor to trigger the activity-dependent phosphorylation of Akt and GSK3.

  12. Visible light regulates neurite outgrowth of nerve cells

    OpenAIRE

    Higuchi, Akon; Watanabe, Toru; Noguchi, Yusuke; Chang, Yung; Chen, Wen-Yih; Matsuoka, Yuki

    2007-01-01

    The neurite outgrowth of PC12 cells on collagen-coated glass plates under light emitting diode (LED) irradiation at several wavelengths (i.e., 455, 470, 525, 600, 630, 880 and 945 nm) was investigated. No neurite outgrowth was observed during cultivation under irradiation from the lamp of an inverted light microscope through filters (yielding mixed light at ca. 525 nm and more than 800 nm), whereas neurite outgrowth was observed during cultivation in the dark. When these cells were irradiated...

  13. Common peroneal nerve dysfunction

    Science.gov (United States)

    ... toe-out movements Tests of nerve activity include: Electromyography (EMG, a test of electrical activity in muscles) Nerve ... Peroneal neuropathy. In: Preston DC, Shapiro BE, eds. Electromyography and Neuromuscular Disorders . 3rd ed. Philadelphia, PA: Elsevier; ...

  14. Biological conduits combining bone marrow mesenchymal stem cells and extracellular matrix to treat long-segment sciatic nerve defects

    Institute of Scientific and Technical Information of China (English)

    Yang Wang; Zheng-wei Li; Min Luo; Ya-jun Li; Ke-qiang Zhang

    2015-01-01

    The transplantation of polylactic glycolic acid conduits combining bone marrow mesenchymal stem cells and extracellular matrix gel for the repair of sciatic nerve injury is effective in some re-spects, but few data comparing the biomechanical factors related to the sciatic nerve are available. In the present study, rabbit models of 10-mm sciatic nerve defects were prepared. The rabbit models were repaired with autologous nerve, a polylactic glycolic acid conduit+bone marrow mesenchymal stem cells, or a polylactic glycolic acid conduit+bone marrow mesenchymal stem cells+extracellular matrix gel. After 24 weeks, mechanical testing was performed to determine the stress relaxation and creep parameters. Following sciatic nerve injury, the magnitudes of the stress decrease and strain increase at 7,200 seconds were largest in the polylactic glycolic acid conduit+bone marrow mesenchymal stem cells+extracellular matrix gel group, followed by the polylactic glycolic acid conduit+bone marrow mesenchymal stem cells group, and then the autologous nerve group. Hematoxylin-eosin staining demonstrated that compared with the poly-lactic glycolic acid conduit+bone marrow mesenchymal stem cells group and the autologous nerve group, a more complete sciatic nerve regeneration was found, including good myelination, regularly arranged nerve ifbers, and a completely degraded and resorbed conduit, in the polylac-tic glycolic acid conduit+bone marrow mesenchymal stem cells+extracellular matrix gel group. These results indicate that bridging 10-mm sciatic nerve defects with a polylactic glycolic acid conduit+bone marrow mesenchymal stem cells+extracellular matrix gel construct increases the stress relaxation under a constant strain, reducing anastomotic tension. Large elongations under a constant physiological load can limit the anastomotic opening and shift, which is ben-eifcial for the regeneration and functional reconstruction of sciatic nerve. Better regeneration was found with the

  15. Physical activity modulates nerve plasticity and stimulates repair after Achilles tendon rupture.

    Science.gov (United States)

    Bring, Daniel K-I; Kreicbergs, Andris; Renstrom, Per A F H; Ackermann, Paul W

    2007-02-01

    In a rat model of tendon rupture using semiquantitative methodology, healing was assessed according to the diameter of newly organized collagen and the occurrence of the sensory neuropeptides (SP, CGRP) in relation to different levels of physical activity. Normally, innervation of the Achilles tendon is confined to the paratenon. After rupture new nerve fibers grow into the tendon proper, but disappear after healing. In a first experiment to establish peak tissue and nerve regeneration after rupture, tendon tissues from freely moving rats were collected consecutively over 16 weeks. A peak increase in organized collagen and nerve ingrowth was observed between week 2 to 4 post rupture. Therefore, in a second experiment week 4 was chosen to assess the effect of physical activity on tendon healing in three groups of rats, that is, wheel running, plaster treated, and freely moving (controls). In the wheel-running group, the diameter of newly organized collagen was 94% ( p = 0.001) greater than that in the plaster-treated group and 48% ( p = 0.02) greater than that in the controls. Inversely, the neuronal occurrence of CGRP in the tendon proper was 57% ( p = 0.02) lower in the wheel-running group than that in the plaster-treated group and 53% ( p = 0.02) lower than that in the controls, suggesting an earlier neuronal in-growth and disappearance in the more active group. Physical activity speeds up tendon healing, which may prove to be linked to accelerated neuronal plasticity.

  16. Fractional cable equation models for anomalous electrodiffusion in nerve cells: infinite domain solutions.

    Science.gov (United States)

    Langlands, T A M; Henry, B I; Wearne, S L

    2009-12-01

    We introduce fractional Nernst-Planck equations and derive fractional cable equations as macroscopic models for electrodiffusion of ions in nerve cells when molecular diffusion is anomalous subdiffusion due to binding, crowding or trapping. The anomalous subdiffusion is modelled by replacing diffusion constants with time dependent operators parameterized by fractional order exponents. Solutions are obtained as functions of the scaling parameters for infinite cables and semi-infinite cables with instantaneous current injections. Voltage attenuation along dendrites in response to alpha function synaptic inputs is computed. Action potential firing rates are also derived based on simple integrate and fire versions of the models. Our results show that electrotonic properties and firing rates of nerve cells are altered by anomalous subdiffusion in these models. We have suggested electrophysiological experiments to calibrate and validate the models. PMID:19221755

  17. Monitoring of immune cell response to B cell depletion therapy and nerve root injury using SPIO enhanced MRI

    Science.gov (United States)

    Thorek, Daniel L.

    2009-12-01

    Magnetic resonance (MR) is a robust platform for non-invasive, high-resolution anatomical imaging. However, MR imaging lacks the requisite sensitivity and contrast for imaging at the cellular level. This represents a clinical impediment to greater diagnostic accuracy. Recent advances have allowed for the in vivo visualization of populations and even of individual cells using superparamagnetic iron oxide (SPIO) MR contrast agents. These nanoparticles, commonly manifested as a core of a single iron oxide crystal or cluster of crystals coated in a biocompatible shell, function to shorten proton relaxation times. In MR imaging these constructs locally dephase protons, resulting in a decrease in signal (hypointensity) localized to the region of accumulation of SPIO. In the context of immune cell imaging, SPIO can provide insight into the cellular migration patterns, trafficking, temporal dynamics and progression of diseases and their related pathological states. Furthermore, by visualizing the presence and activity of immune cells, SPIO-enabled cellular imaging can help evaluate the efficacy of therapy in immune disorders. This thesis examines the production, modification and application of SPIO in a range of in vitro and in vivo immune-response-relevant cellular systems. The role of different nanoparticle characteristics including diameter, surface charge and concentration are investigated in the labeling of T cells in culture. Following optimization of SPIO loading conditions for lymphocytes, the effect these particles have on the activation of primary B cells are elucidated. B cells are tracked using a variety of modalities, with and without the application of B cell depleting therapy. This is to evaluate the efficacy of SPIO as in vivo marker for B cell distribution. Unmodified SPIO were applied to monitor macrophage infiltration in a transient nerve root compression model, with implications for neck pain diagnosis and treatment. Nanoparticle accumulation and MR

  18. Effect of Human Cytomegalovirus Infection on Nerve Growth Factor Expression in Human Glioma U251 Cells

    Institute of Scientific and Technical Information of China (English)

    HAI-TAO WANG; BIN WANG; ZHI-JUN LIU; ZHI-QIANG BAI; LING LI; HAI-YAN LIU; DONG-MENG QIAN; ZHI-YONG YAN; XU-XIA SONG

    2009-01-01

    Objectives To explore the change of endogenic nerve growth factor (NGF) expression in human glioma cells infected with human cytomegalovirus (HCMV). Methods U251 cells were cultured in RPMI 1640 culture medium and infected with HCMV AD169 strain in vitro to establish a cell model of viral infection. Morphologic changes of U251 cells were observed under inverted microscope before and after infection with HCMV. Expression of NGF gene and protein of cells was detected by RT-PCR and Western blotting before and after infection with HCMV. Results The cytopathic effects of HCMV-infected cells appeared on day 5 after infection. However, differential NGF expression was evident on day 7. NGF expression was decreased significantly in U251 cells on day 7 after infection in comparison with control group (P<0.05). Conclusion HCMV can down-regulate endogenous NGF levels in human glioma cell line U251.

  19. A Novel Model for Acute Peripheral Nerve Injury in the Horse and Evaluation of the Effect of Mesenchymal Stromal Cells Applied In Situ on Nerve Regeneration: A Preliminary Study

    Science.gov (United States)

    Cruz Villagrán, Claudia; Schumacher, Jim; Donnell, Robert; Dhar, Madhu S.

    2016-01-01

    Transplantation of mesenchymal stromal cells (MSCs) to sites of experimentally created nerve injury in laboratory animals has shown promising results in restoring nerve function. This approach for nerve regeneration has not been reported in horses. In this study, we first evaluated the in vitro ability of equine bone marrow-derived MSCs (EBM-MSCs) to trans-differentiate into Schwann-like cells and subsequently tested the MSCs in vivo for their potential to regenerate a transected nerve after implantation. The EBM-MSCs from three equine donors were differentiated into SCLs for 7 days, in vitro, in the presence of specialized differentiation medium and evaluated for morphological characteristics, by using confocal microscopy, and for protein characteristics, by using selected Schwann cell markers (GFAP and S100b). The EBM-MSCs were then implanted into the fascia surrounding the ramus communicans of one fore limb of three healthy horses after a portion of this nerve was excised. The excised portion of the nerve was examined histologically at the time of transection, and stumps of the nerve were examined histologically at day 45 after transplantation. The EBM-MSCs from all donors demonstrated morphological and protein characteristics of those of Schwann cells 7 days after differentiation. Nerves implanted with EBM-MSCs after nerve transection did not show evidence of nerve regeneration at day 45. Examination of peripheral nerves collected 45 days after injury and stem cell treatment revealed no histological differences between nerves treated with MSCs and those treated with isotonic saline solution (controls). The optimal delivery of MSCs and the model suitable to study the efficacy of MSCs in nerve regeneration should be investigated. PMID:27695697

  20. Axon-Schwann cell interactions during peripheral nerve regeneration in zebrafish larvae

    OpenAIRE

    Ceci, Maria Laura; Mardones-Krsulovic, Camila; SÁNCHEZ, MARIO; Valdivia, Leonardo E.; Allende, Miguel L

    2014-01-01

    Background Peripheral nerve injuries can severely affect the way that animals perceive signals from the surrounding environment. While damage to peripheral axons generally has a better outcome than injuries to central nervous system axons, it is currently unknown how neurons re-establish their target innervations to recover function after injury, and how accessory cells contribute to this task. Here we use a simple technique to create reproducible and localized injury in the posterior lateral...

  1. Enhancement of Median Nerve Regeneration by Mesenchymal Stem Cells Engraftment in an Absorbable Conduit: Improvement of Peripheral Nerve Morphology with Enlargement of Somatosensory Cortical Representation.

    Directory of Open Access Journals (Sweden)

    Julia Teixeira Oliveira

    2014-10-01

    Full Text Available We studied the morphology and the cortical representation of the median nerve (MN, 10 weeks after a transection immediately followed by treatment with tubulization using a polycaprolactone (PCL conduit with or without bone marrow-derived mesenchymal stem cell (MSC transplant. In order to characterize the cutaneous representation of MN inputs in primary somatosensory cortex (S1, electrophysiological cortical mapping of the somatosensory representation of the forepaw and adjacent body parts was performed after acute lesion of all brachial plexus nerves, except for the MN. This was performed in ten adult male Wistar rats randomly assigned in 3 groups: MN Intact (n=4, PCL-Only (n=3 and PCL+MSC (n=3. Ten weeks before mapping procedures in animals from PCL-Only and PCL+MSC groups, animal were subjected to MN transection with removal of a 4-mm-long segment, immediately followed by suturing a PCL conduit to the nerve stumps with (PCL+MSC group or without (PCL-Only group injection of MSC into the conduit. After mapping the representation of the MN in S1, animals had a segment of the regenerated nerve processed for light and transmission electron microscopy. For histomorphometric analysis of the nerve segment, sample size was increased to 5 animals per experimental group. The PCL+MSC group presented a higher number of myelinated fibers and a larger cortical representation of MN inputs in S1 (3,383±390 fibers; 2.3 mm2, respectively than the PCL-Only group (2,226±575 fibers; 1.6 mm2. In conclusion, MSC-based therapy associated with PCL conduits can improve MN regeneration. This treatment seems to rescue the nerve representation in S1, thus minimizing the stabilization of new representations of adjacent body parts in regions previously responsive to the MN.

  2. Graphene-Based Interfaces Do Not Alter Target Nerve Cells.

    Science.gov (United States)

    Fabbro, Alessandra; Scaini, Denis; León, Verónica; Vázquez, Ester; Cellot, Giada; Privitera, Giulia; Lombardi, Lucia; Torrisi, Felice; Tomarchio, Flavia; Bonaccorso, Francesco; Bosi, Susanna; Ferrari, Andrea C; Ballerini, Laura; Prato, Maurizio

    2016-01-26

    Neural-interfaces rely on the ability of electrodes to transduce stimuli into electrical patterns delivered to the brain. In addition to sensitivity to the stimuli, stability in the operating conditions and efficient charge transfer to neurons, the electrodes should not alter the physiological properties of the target tissue. Graphene is emerging as a promising material for neuro-interfacing applications, given its outstanding physico-chemical properties. Here, we use graphene-based substrates (GBSs) to interface neuronal growth. We test our GBSs on brain cell cultures by measuring functional and synaptic integrity of the emerging neuronal networks. We show that GBSs are permissive interfaces, even when uncoated by cell adhesion layers, retaining unaltered neuronal signaling properties, thus being suitable for carbon-based neural prosthetic devices. PMID:26700626

  3. LEPTIN SIGNALING IN THE NUCLEUS TRACTUS SOLITARII INCREASES SYMPATHETIC NERVE ACTIVITY TO THE KIDNEY

    OpenAIRE

    Mark, Allyn L.; Agassandian, Khristofor; Morgan, Donald A.; Liu, Xuebo; Cassell, Martin D.; Rahmouni, Kamal

    2008-01-01

    The hypothalamic arcuate nucleus was initially regarded as the principal site of leptin action, but there is increasing evidence for functional leptin receptors (Ob-Rb) in extra-hypothalamic sites, including the nucleus tractus solitarii (NTS). We previously demonstrated that arcuate injection of leptin increases sympathetic nerve activity (SNA) to brown adipose tissue (BAT) and kidney. In this study, we tested the hypothesis that leptin signaling in the NTS affects sympathetic neural outflow...

  4. Skin sympathetic nerve activity in humans during exposure to emotionally-charged images: sex differences

    OpenAIRE

    Brown, Rachael; Macefield, Vaughan G.

    2014-01-01

    While it is known that anxiety or emotional arousal affects skin sympathetic nerve activity (SSNA), the galvanic skin response (GSR) is the most widely used parameter to infer increases in SSNA during stress or emotional studies. We recently showed that SSNA provides a more sensitive measure of emotional state than effector-organ responses. The aim of the present study was to assess whether there are gender differences in the responses of SSNA and other physiological parameters such as blood ...

  5. Modulation of muscle sympathetic nerve activity to muscle heating during dynamic exercise

    OpenAIRE

    Cook, Jonathan S.; Ray, Chester A.

    2009-01-01

    Previous studies from our laboratory have demonstrated that altering muscle temperature of the exercising forearm can elicit changes in muscle sympathetic nerve activity (MSNA) during ischemic isometric handgrip. The purpose of the current study was to determine the interactive effect of muscle temperature and blood flow on MSNA responses during dynamic handgrip (DHG). Eight subjects performed two bouts of graded DHG to fatigue followed by 2 min of postexercise muscle ischemia (PEMI). Local h...

  6. Excitatory and inhibitory effects of prolactin release activated by nerve stimulation in rat anterior pituitary

    Directory of Open Access Journals (Sweden)

    Gao Li-Zhi

    2009-12-01

    Full Text Available Abstract Background A series of studies showed the presence of substantial amount of nerve fibers and their close relationship with the anterior pituitary gland cells. Our previous studies have suggested that aside from the classical theory of humoral regulation, the rat anterior pituitary has direct neural regulation on adrenocorticotropic hormone release. In rat anterior pituitary, typical synapses are found on every type of the hormone-secreting cells, many on lactotrophs. The present study was aimed at investigating the physiological significance of this synaptic relationship on prolactin release. Methods The anterior pituitary of rat was sliced and stimulated with electrical field in a self-designed perfusion chamber. The perfusate was continuously collected in aliquots and measured by radioimmunoassay for prolactin levels. After statistic analysis, differences of prolactin concentrations within and between groups were outlined. Results The results showed that stimulation at frequency of 2 Hz caused a quick enhancement of prolactin release, when stimulated at 10 Hz, prolactin release was found to be inhibited which came slower and lasted longer. The effect of nerve stimulation on prolactin release is diphasic and frequency dependent. Conclusions The present in vitro study offers the first physiological evidence that stimulation of nerve fibers can affect prolactin release in rat anterior pituitary. Low frequency stimulation enhances prolactin release and high frequency mainly inhibits it.

  7. Substance P combined with epidermal stem cells promotes wound healing and nerve regeneration in diabetes mellitus

    Institute of Scientific and Technical Information of China (English)

    Fei-bin Zhu; Xiang-jing Fang; De-wu Liu; Ying Shao; Hong-yan Zhang; Yan Peng; Qing-ling Zhong; Yong-tie Li; De-ming Liu

    2016-01-01

    Exogenous substance P accelerates wound healing in diabetes, but the mechanism remains poorly understood. Here, we established a rat model by intraperitoneally injecting streptozotocin. Four wounds (1.8 cm diameter) were drilled using a self-made punch onto the back, bilateral to the vertebral column, and then treated using amniotic membrane with epidermal stem cells and/or substance P around and in the middle of the wounds. With the combined treatment the wound-healing rate was 100% at 14 days. With prolonged time, type I col-lagen content gradually increased, yet type III collagen content gradually diminished. Abundant protein gene product 9.5- and substance P-immunoreactive nerve ifbers regenerated. Partial nerve ifber endings extended to the epidermis. The therapeutic effects of combined substance P and epidermal stem cells were better than with amniotic membrane and either factor alone. Our results suggest that the com-bination of substance P and epidermal stem cells effectively contributes to nerve regeneration and wound healing in diabetic rats.

  8. Substance P combined with epidermal stem cells promotes wound healing and nerve regeneration in diabetes mellitus.

    Science.gov (United States)

    Zhu, Fei-Bin; Fang, Xiang-Jing; Liu, De-Wu; Shao, Ying; Zhang, Hong-Yan; Peng, Yan; Zhong, Qing-Ling; Li, Yong-Tie; Liu, De-Ming

    2016-03-01

    Exogenous substance P accelerates wound healing in diabetes, but the mechanism remains poorly understood. Here, we established a rat model by intraperitoneally injecting streptozotocin. Four wounds (1.8 cm diameter) were drilled using a self-made punch onto the back, bilateral to the vertebral column, and then treated using amniotic membrane with epidermal stem cells and/or substance P around and in the middle of the wounds. With the combined treatment the wound-healing rate was 100% at 14 days. With prolonged time, type I collagen content gradually increased, yet type III collagen content gradually diminished. Abundant protein gene product 9.5- and substance P-immunoreactive nerve fibers regenerated. Partial nerve fiber endings extended to the epidermis. The therapeutic effects of combined substance P and epidermal stem cells were better than with amniotic membrane and either factor alone. Our results suggest that the combination of substance P and epidermal stem cells effectively contributes to nerve regeneration and wound healing in diabetic rats.

  9. Interaction between dendritic cells and nerve fibres in lymphoid organs after oral scrapie exposure.

    Science.gov (United States)

    Dorban, Gauthier; Defaweux, Valérie; Demonceau, Caroline; Flandroy, Sylvain; Van Lerberghe, Pierre-Bernard; Falisse-Poirrier, Nandini; Piret, Joëlle; Heinen, Ernst; Antoine, Nadine

    2007-12-01

    In transmissible spongiform encephalopathies (TSEs), the infectious agent, called PrPsc, an abnormal isoform of the cellular prion protein, accumulates and replicates in lymphoid organs before affecting the nervous system. To clarify the cellular requirements for the neuroinvasion of the scrapie agent from the lymphoid organs to the central nervous system, we have studied, by confocal microscopy, the innervations within Peyer's patches, mesenteric lymph nodes and the spleen of mice in physiological conditions and after oral exposure to prion. Contacts between nerve fibres and PrPsc-associated cells, dendritic cells (DCs) and follicular dendritic cells (FDCs), were evaluated in preclinical prion-infected mice. Using a double immunolabelling strategy, we demonstrated the lack of innervation of PrPsc-accumulating cells (FDCs). Contacts between nerve fibers and PrPsc-propagating cells (DCs) were detected in T-cell zones and cell-trafficking areas. This supports, for the first time, the possible implication of dendritic cells in the prion neuroinvasion process. PMID:17823814

  10. Survival and migration of Schwann cells after the vascularized peripheral nerve grafted into spinal cord in rats

    Institute of Scientific and Technical Information of China (English)

    GUO Qing-shan; WANG Ai-min; WANG Xiao-jun; SUN Hong-zhen; DU Quan-yin

    2005-01-01

    Objective:To study the survival and ability of inducing axonal regeneration of the Schwann cells after the peripheral nerve being grafted into spinal cord. Methods:A total of 30 adult female Wistar rats were randomly divided into the VN (vascularized peripheral nerve) and PN (peripheral nerve) groups. A 5-mm spinal cord defect of the left posterior column was made at the T1-3 vertebral level. The defect was grafted with the vascularized or isolated peripheral nerve respectively. The survival and proliferation of the Schwann cells were assessed by histological and morphometric analysis 8 weeks after the operation. Results:In the VN group, the peripheral nerve grew into the cord with lots of Schwann cells survived and proliferated, and had more NF and S-100 positive fibers than in the PN group. Conclusion:The vascularized peripheral nerve enhances the survival and proliferation of the Schwann cells and prompts the regeneration of injured axon of the central nerve system to certain degree.

  11. What can we learn about neural control of the cardiovascular system by studying rhythms in sympathetic nerve activity?

    Science.gov (United States)

    Barman, Susan M

    2016-05-01

    Since the first recordings of sympathetic nerve activity in the 1930s, it was very clear that the activity was organized into bursts synchronized to the respiratory and cardiac cycles. Since the early studies, evidence has accumulated showing that sympathetic neural networks are quite complex and generate a variety of periodicities that range between ~0.04 and 10Hz, depending on the physiological state, type of nerve being analyzed, age of the subject, and the species. Despite the ubiquity of sympathetic rhythms, many investigators have failed to consider this oscillatory characteristic of sympathetic nerve activity and instead rely on simply quantifying changes in the level of activity to make decisions about the role of the sympathetic nervous system in mediating certain behaviors. This review highlights work that shows the importance of including an assessment of the frequency characteristics of sympathetic nerve activity. PMID:25681532

  12. Inhibition of guinea-pig and human sensory nerve activity and the cough reflex in guinea-pigs by cannabinoid (CB2) receptor activation

    OpenAIRE

    Patel, Hema J; Birrell, Mark A; Crispino, Natascia; Hele, David J.; Venkatesan, Priya; Barnes, Peter J; Yacoub, Magdi H.; Belvisi, Maria G.

    2003-01-01

    There is considerable interest in novel therapies for cough, since currently used agents such as codeine have limited beneficial value due to the associated side effects. Sensory nerves in the airways mediate the cough reflex via activation of C-fibres and RARs. Evidence suggests that cannabinoids may inhibit sensory nerve-mediated responses.We have investigated the inhibitory actions of cannabinoids on sensory nerve depolarisation mediated by capsaicin, hypertonic saline and PGE2 on isolated...

  13. An in vitro method for recording single unit afferent activity from mesenteric nerves innervating isolated segments of rat ileum.

    Science.gov (United States)

    Sharkey, K A; Cervero, F

    1986-04-01

    A technique has been developed for recording single unit afferent activity from mesenteric nerves in isolated segments of rat distal ileum in vitro. The preparation consists of a 3-cm segment of ileum, containing a single neurovascular bundle, held horizontally in an organ bath. One end of the segment is attached to a tension transducer to record changes in longitudinal tension of the gut muscle and the other is connected to a pressure transducer to record changes in intra-luminal pressure. Electromyographic activity of the smooth muscle is recorded using glass-insulated tungsten microelectrodes inserted in the wall of the gut. Afferent nerve activity is recorded with a monopolar platinum wire electrode from filaments of the mesenteric nerves that run between the artery and vein supplying the segment. This preparation permits the detailed analysis of the electrical activity of intestinal afferent nerve fibres correlated with mechanical and chemical events occurring naturally in the gut or imposed experimentally on it.

  14. Human umbilical cord mesenchymal stem cell-loaded amniotic membrane for the repair of radial nerve injury

    Institute of Scientific and Technical Information of China (English)

    Zhi Li; Hanjiao Qin; Zishan Feng; Wei Liu; Ye Zhou; Lifeng Yang; Wei Zhao; Youjun Li

    2013-01-01

    In this study, we loaded human umbilical cord mesenchymal stem cells onto human amniotic membrane with epithelial cells to prepare nerve conduits, i.e., a relatively closed nerve regeneration chamber. After neurolysis, the injured radial nerve was enwrapped with the prepared nerve conduit, which was fixed to the epineurium by sutures, with the cellon the inner surface of the conduit. Simultaneously, a 1.0 mL aliquot of human umbilical cord mesenchymal stem cellsuspension was injected into the distal and proximal ends of the injured radial nerve with 1.0 cm intervals. A total of 1.75 × 107 cells were seeded on the amniotic membrane. In the control group, patients received only neurolysis. At 12 weeks after celltransplantation, more than 80%of patients exhibited obvious improvements in muscular strength, and touch and pain sensations. In contrast, these improve-ments were observed only in 55-65% of control patients. At 8 and 12 weeks, muscular electro-physiological function in the region dominated by the injured radial nerve was significantly better in the transplantation group than the control group. After celltransplantation, no immunological rejec-tions were observed. These findings suggest that human umbilical cord mesenchymal stem cel-loaded amniotic membrane can be used for the repair of radial nerve injury.

  15. Primary, non-exophytic, optic nerve germ cell tumors.

    Science.gov (United States)

    DiLuna, Michael L; Two, Aimee M; Levy, Gillian H; Patel, Toral; Huttner, Anita J; Duncan, Charles C; Piepmeier, Joseph M

    2009-12-01

    Tumors of the optic chiasm are relatively uncommon and usually associated with phakomatoses such as neurofibromatosis. Even more rare is the presentation of a primary, non-exophytic, isolated optic chiasm germ cell tumor (GCT). These tumors have imaging characteristics nearly indistinguishable from optic chiasmatic gliomas (OCGs). Herein we describe two cases of young men who presented with similar findings of progressive, painless visual loss and hypothalamic-pituitary-adrenal axis dysfunction including diabetes insipidus. Brain imaging was non-diagnostic and suggestive of an OCG. Pathology demonstrated GCTs in each case highlighting the importance of biopsy confirmation of the diagnosis. Both patients underwent a pterional craniotomy and sub-frontal approach to the optic chiasm. The chiasm was diffusely enlarged and discolored in each case without evidence of sellar, suprasellar or perichiasmatic pathology. Pathology demonstrated a malignant mixed GCT in the first patient and a germinoma in the second. This case series highlights the importance of tissue biopsy for patients with progressive symptoms from optic chiasm tumors. Furthermore, this is the first report of a primary, non-exophytic malignant mixed GCT. As the treatment regimens differ widely between optic chiasm GCTs and chiasm gliomas, tissue diagnosis is important. PMID:19554263

  16. Co-transplantation of macaque autologous Schwann cells and human embryonic nerve stem cells in treatment of macaque Parkinson's disease

    Institute of Scientific and Technical Information of China (English)

    Ying Xia; Chengchuan Jiang; Zuowei Cao; Keshan Shi; Yang Wang

    2012-01-01

    Objective:To investigate the therapeutic effects of co-transplantation with Schwann cells (SCs) and human embryonic nerve stem cells (NSCs) on macaque Parkinson's disease (PD). Methods:Macaque autologous SCs and human embryonic NSCs were adopted for the treatment of macaque PD. Results: Six months after transplantation, positron emission computerized tomography showed that 18F-FP-β-CIT was significantly concentrated in the injured striatum in the co-transplanted group. Immunohistochemical staining of transplanted area tissue showed migration of tyroxine hydroxylase positive cells from the transplant area to the surrounding area was significantly increased in the co-transplanted group. Conclusions: Co-transplantation of SCs and NSCs could effectively cure PD in macaques. SCs harvested from the autologous peripheral nerves can avoid rejection and the ethics problems, so it is expected to be applied clinically.

  17. Bone Marrow-Derived Cells as a Therapeutic Approach to Optic Nerve Diseases

    Directory of Open Access Journals (Sweden)

    Louise A. Mesentier-Louro

    2016-01-01

    Full Text Available Following optic nerve injury associated with acute or progressive diseases, retinal ganglion cells (RGCs of adult mammals degenerate and undergo apoptosis. These diseases have limited therapeutic options, due to the low inherent capacity of RGCs to regenerate and due to the inhibitory milieu of the central nervous system. Among the numerous treatment approaches investigated to stimulate neuronal survival and axonal extension, cell transplantation emerges as a promising option. This review focuses on cell therapies with bone marrow mononuclear cells and bone marrow-derived mesenchymal stem cells, which have shown positive therapeutic effects in animal models of optic neuropathies. Different aspects of available preclinical studies are analyzed, including cell distribution, potential doses, routes of administration, and mechanisms of action. Finally, published and ongoing clinical trials are summarized.

  18. Bone Marrow-Derived Cells as a Therapeutic Approach to Optic Nerve Diseases

    Science.gov (United States)

    Mesentier-Louro, Louise A.; Zaverucha-do-Valle, Camila; Rosado-de-Castro, Paulo H.; Silva-Junior, Almir J.; Pimentel-Coelho, Pedro M.; Mendez-Otero, Rosalia; Santiago, Marcelo F.

    2016-01-01

    Following optic nerve injury associated with acute or progressive diseases, retinal ganglion cells (RGCs) of adult mammals degenerate and undergo apoptosis. These diseases have limited therapeutic options, due to the low inherent capacity of RGCs to regenerate and due to the inhibitory milieu of the central nervous system. Among the numerous treatment approaches investigated to stimulate neuronal survival and axonal extension, cell transplantation emerges as a promising option. This review focuses on cell therapies with bone marrow mononuclear cells and bone marrow-derived mesenchymal stem cells, which have shown positive therapeutic effects in animal models of optic neuropathies. Different aspects of available preclinical studies are analyzed, including cell distribution, potential doses, routes of administration, and mechanisms of action. Finally, published and ongoing clinical trials are summarized. PMID:26649049

  19. MR imaging and T2 measurements in peripheral nerve repair with activation of Toll-like receptor 4 of neurotmesis

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xiang; Zhang, Fang; Lu, Liejing; Li, Haojiang; Wen, Xuehua; Shen, Jun [Sun Yat-Sen University, Department of Radiology, Sun Yat-Sen Memorial Hospital, Guangzhou, Guangdong (China)

    2014-05-15

    To investigate the role of MR imaging in neurotmesis combined with surgical repair and Toll-like receptor 4 (TLR4) activation. Forty-eight rats received subepineurial microinjection of the TLR4 agonist lipopolysaccharide (LPS, n = 24) or phosphate buffered saline (PBS, n = 24) immediately after surgical repair of the transected sciatic nerve. Sequential fat-suppressed T2-weighted imaging and quantitative T2 measurements were obtained at 3, 7, 14 and 21 days after surgery, with histologic assessments performed at regular intervals. T2 relaxation times and histological quantification of the distal stumps were measured and compared. The distal stumps of transected nerves treated with LPS or PBS both showed persistent enlargement and hyperintense signal. T2 values of the distal stumps showed a rapid rise to peak level followed by a rapid decline pattern in nerves treated with LPS, while exhibiting a slow rise to peak value followed by a slow decline in nerves treated with PBS. Nerves treated with LPS exhibited more prominent macrophage recruitment, faster myelin debris clearance and more pronounced nerve regeneration. Nerves treated with TLR4 activation had a characteristic pattern of T2 value change over time. Longitudinal T2 measurements can be used to detect the enhanced repair effect associated with TLR4 activation in the surgical repair of neurotmesis. (orig.)

  20. Specific hunger- and satiety-induced tuning of guinea pig enteric nerve activity.

    Science.gov (United States)

    Roosen, Lina; Boesmans, Werend; Dondeyne, Marjan; Depoortere, Inge; Tack, Jan; Vanden Berghe, Pieter

    2012-09-01

    Although hunger and satiety are mainly centrally regulated, there is convincing evidence that also gastrointestinal motor activity and hormone fluctuations significantly contribute to appetite signalling. In this study, we investigated how motility and enteric nerve activity are set by fasting and feeding. By means of video-imaging, we tested whether peristaltic activity differs in ex vivo preparations from fasted and re-fed guinea pigs. Ca(2+) imaging was used to investigate whether the feeding state directly alters neuronal activity, either occurring spontaneously or evoked by (an)orexigenic signalling molecules. We found that pressure-induced (2 cmH(2)O) peristaltic activity occurs at a higher frequency in ileal segments from re-fed animals (re-fed versus fasted, 6.12 ± 0.22 vs. 4.84 ± 0.52 waves min(-1), P = 0.028), even in vitro hours after death. Myenteric neuronal responses were tuned to the feeding status, since neurons in tissues from re-fed animals remained hyper-responsive to high K(+)-evoked depolarization (P < 0.001) and anorexigenic molecules (P < 0.001), while being less responsive to orexigenic ghrelin (P = 0.013). This illustrates that the feeding status remains ‘imprinted' ex vivo. We were able to reproduce this feeding state-related memory in vitro and found humoral feeding state-related factors to be implicated. Although the molecular link with hyperactivity is not entirely elucidated yet, glucose-dependent pathways are clearly involved in tuning neuronal excitability. We conclude that a bistable memory system that tunes neuronal responses to fasting and re-feeding is present in the enteric nervous system, increasing responses to depolarization and anorexigenic molecules in the re-fed state, while decreasing responses to orexigenic ghrelin. Unlike the hypothalamus, where specific cell populations sensitive to either orexigenic or anorexigenic molecules exist, the enteric feeding state-related memory system is present at the functional level

  1. GD3+ cells in the adult rat optic nerve are ramified microglia rather than O-2Aadult progenitor cells.

    Science.gov (United States)

    Wolswijk, G

    1994-04-01

    The adult central nervous system (CNS) contains a population of adult oligodendrocyte-type-2 astrocyte (O-2A) progenitor cells (O-2Aadult progenitor cells). These cells may provide a source of the new oligodendrocytes that are needed to repair demyelinated lesions. In order to examine the role of O-2Aadult progenitor cells in the regeneration of the oligodendrocyte population following demyelinating damage, it is essential to be able to identify such cells unambiguously in sections of adult CNS tissue. The present study examined whether antibodies to the ganglioside GD3 specifically label O-2Aadult progenitor cells in cultures and sections of adult optic nerve, since previous studies on the developing CNS had suggested that O-2Aperinatal progenitor cells were GD3+ in vitro and in vivo. Evidence is presented indicating that, although O-2Aadult progenitor cells in vitro were labelled with the R24 mAb (an anti-GD3 mAb), all GD3+ cells in sections of adult optic nerve bound the OX-42 mAb and the B4 isolectin derived from Griffonia Simplicifolia, and thus were not O-2Aadult progenitor cells, but ramified microglia. The data suggest that O-2Aadult progenitor cells become GD3+ when placed in culture and that ramified microglia lose GD3-expression in vitro.

  2. [Biophysics of nerve excitation].

    Science.gov (United States)

    Kol'e, O R; Maksimov, G V

    2010-01-01

    The studies testifying to the presence of the interrelation between the physiological functions of the organism and physical and chemical processes in nerves are discussed. Changes in some physical and chemical parameters observed both upon elicited rhythmic exaltation of nerves and during the spontaneous rhythmic activity of neurons are analyzed. Upon rhythmic exaltation, a complex of physical and chemical processes is triggered, and reversible structural and metabolic rearrangements at the subcellular and molecular levels occur that do not take place during the generation of a single action potential. Thus, only in conditions of rhythmic exaltation of a nerve, it is possible to reveal those processes that provide exaltation of nerves in the organism. The future possibilities of the investigations combining the biophysical and physiological approaches are substantiated. Characteristic changes in physicochemical parameters are observed in nerves during the generation of a series of action potentials of different frequency and duration ("frequency dependence") under normal physiological conditions, as well as in extreme situations and in nerve pathology. The structural and metabolic rearrangements are directly related to the mode of rhythmic exaltation and proceed both in the course of rhythmic exaltation and after its termination. Participation and the basic components of the nervous fulcrum (an axon, Shwan cell, myelin, subcellular organelles) in the realization of rhythmic exaltation is shown. In the coordination of all processes involved in rhythmic exaltation, the main role is played by the systems of redistribution and transport of intercellular and endocellular calcium. The idea is put forward that myelin of nerve fibers is not only an isolator, but also an "intercellular depot" of calcium and participates in the redistribution of different ions. Thus, the rhythmic excitation is of great importance in the realization of some physiological functions, the

  3. Human primordial germ cells migrate along nerve fibers and Schwann cells from the dorsal hind gut mesentery to the gonadal ridge

    DEFF Research Database (Denmark)

    Møllgård, Kjeld; Jespersen, Åse; Lutterodt, Melissa Catherine;

    2010-01-01

    The aim of this study was to investigate the spatiotemporal development of autonomic nerve fibers and primordial germ cells (PGCs) along their migratory route from the dorsal mesentery to the gonadal ridges in human embryos using immunohistochemical markers and electron microscopy. Autonomic nerve...... PGCs arrive at the gonadal ridge between 29 and 33 days pc. In conclusion, our data suggest that PGCs in human embryos preferentially migrate along autonomic nerve fibers from the dorsal mesentery to the developing gonad where they are delivered via a fine nerve plexus....

  4. Respiratory modulation of sympathetic nerve activity is enhanced in male rat offspring following uteroplacental insufficiency.

    Science.gov (United States)

    Menuet, C; Wlodek, M E; Fong, A Y; Allen, A M

    2016-06-01

    Sympathetic nerve activity to the cardiovascular system displays prominent respiratory-related modulation which leads to the generation of rhythmic oscillations in blood pressure called Traube-Hering waves. An amplification of this respiratory modulation of sympathetic activity is observed in hypertension of both genetic, the spontaneously hypertensive rat, and induced, chronic intermittent hypoxia or maternal protein restriction during gestation, origin. Male offspring of mothers with uteroplacental insufficiency, induced by bilateral uterine vessel ligation at 18 days of gestation, are also hypertensive in adulthood. In this study we examined whether these male offspring display altered respiratory modulation of sympathetic activity at pre-hypertensive ages compared to controls. Respiratory, cardiovascular and sympathetic parameters were examined using the working heart-brainstem preparation in 35 day old male rats that had reduced birth weight due to uteroplacental insufficiency. Whilst all respiratory parameters were not different between groups, we observed an enhanced respiratory-related burst of thoracic sympathetic nerve activity and amplified Traube-Hering waves in the growth-restricted group. This group also showed an increased sympathetic and bradycardic response to activation of peripheral chemoreceptors. The observations add support to the view that altered respiratory modulation of sympathetic activity represents a common mechanism involved in the development of several forms of hypertension. PMID:26593642

  5. Protective effects of Achyranthes bidentata polypeptides on retinal ganglion cells post-optic nerve crush in rats

    Institute of Scientific and Technical Information of China (English)

    Nan Hu; Qi Zhao; Fangling Zhang; Junfang Zhang; Xiaosong Gu

    2011-01-01

    Achyranthes bidentata polypeptides (ABPP) have been reported to inhibit apoptosis of retinal ganglion cells (RGCs).The present study investigated the protective effects of ABPP on RGCs in a rat model of optic nerve injury.With prolonged injury time,RGC densities were gradually decreased.ABPP (5 μg) significantly increased RGC densities and upregulated growth associated protein 43 expression in rats with optic nerve injury.Results demonstrate that ABPP can protect RGCs and promote axonal growth after optic nerve crush.

  6. Effects of vagus nerve stimulation on parafascicular nucleus neuronal activities in rats

    Institute of Scientific and Technical Information of China (English)

    Yizhe Meng; Jinju Jiao

    2008-01-01

    BACKGROUND: Vagal nerve fibers have many projections to the central nervous system. The anti-epileptic effects of vagus nerve stimulation (VNS) are associated with the thalamus, insular cortex, and other brain regions.OBJECTIVE: To validate the inhibitory effects of vagus nerve stimulation on firing activities of parafascicular nucleus (Pf) neurons in rats. DESIGN, TIME, AND SETTING: The experiment was performed in the Electrophysiological Laboratory of Department of Neurobiology, Liaoning Medical University between September 2006 and September 2007 with multiple-factor self-controlled design.MATERIALS: Twenty-two healthy adult male Sprague Dawley rats were obtained for this experiment. Main instruments: A320R constant electrical stimulation was made by United States World Precision Instruments, Spike2 Biological Signal Processing Systems was provided by British CED Company.METHODS: Under general anesthesia, the left cervical vagus nerve of rats was separated by approximately 1.0 cm. A stimulation electrode was deployed on the vagus nerve, with various settings for VNS parameters.MAIN OUTCOME MEASURES: ① Firing rates of Pf before and after various VNS parameters were measured according to effect (R) ≥ 20%: excited effect, R ≤ -20%: inhibited effect, -20% < R < 20%: no effect. ② Firing rates of excited Pf neurons after various VNS parameters were measured.RESULTS: ① One rat died prior to recording, another was recorded in the wrong brain location, but the remaining 20 rats were included in the final analysis. ② A total of 221 Pf neurons in healthy rats were recorded. The spontaneous firing rats were (6.70 ± 0.56) Hz and varied between 0.34-52.5 Hz. The spontaneous firing rates were significantly increased in 146 neurons (66.1%), increasing from (5.36 ± 0.59) Hz to (8.22 ± 0.81) Hz (P < 0.01). A total of 40 (18.1%) neurons did not respond, and 35 (15.8%) neurons were inhibited. ③ The excitation rates of Pf neurons did not increase with increasing

  7. Protective effects of soybean phospholipid liposome on glutamate-induced nerve cell injury in vitro

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    BACKGROUND: It has been previously reported that soybean phosphatide could reduce the cerebral ischemia damage obviously. Whether soybean phospholipid liposome (SPL) can protect cerebral cortical neurons cultured in vitro from glutamate (Glu)-induced neurotoxicity, particularly nerve cell membrane damage has not been fully investigated.OBJECTIVE: To study the protective effects of SPL on Glu-induced neurotoxicity of neurons in culture,and to discuss the possible mechanisms of neuroprotection.DESIGN: Randomized controlled trial.SETTING: Department of Biochemistry, Liaoning Medical University.MATERIALS: Twelve Sprague-Dawley rats, of either gender, aged 0 to 1 day, were involved in this study.Drugs and reagents: poly-L-lysine and L-glutamate were purchased from Sigma company (USA).METHODS: The study was carried out in the Department of Biochemistry of Jinzhou Medical University from November 2004 to June 2005. Glu(1×10-4 mol/L) was added to cortical neurons in injury group for 3 hours, while different concentrations of SPL (0.2, 0.4, 0.8, 1.6 g/L) were added at the same time in the SPL groups. Neurons in the normal control group were untouched.MAIN OUTCOME MEASURES: According to the instruction of reagent kit, lactate dehydrogenase(LDH) activity and nitric oxide(NO) content in the supematant fluid of the culture medium were assayed, and the activity of nitric oxide synthase (NOS) and superoxide dismutase(SOD),malonaldehyde (MDA) content in the neurocytes were also determined.RESULTS: ①Activities of LDH and NOS, as well as NO content in the supernatant fluid of injury group were significantly higher than those of normal control group (P < 0.01). Activities of LDH and NOS, and NO content in the supematant fluid of SPL groups were significantly lower than those of injury group (P < 0.01).②MDA content of the SPL groups was significantly lower than that of injury group (P < 0.01); SOD activity of neurons in the injury group was significantly lower than that in

  8. Somatic modulation of spinal reflex bladder activity mediated by nociceptive bladder afferent nerve fibers in cats.

    Science.gov (United States)

    Xiao, Zhiying; Rogers, Marc J; Shen, Bing; Wang, Jicheng; Schwen, Zeyad; Roppolo, James R; de Groat, William C; Tai, Changfeng

    2014-09-15

    The goal of the present study was to determine if supraspinal pathways are necessary for inhibition of bladder reflex activity induced by activation of somatic afferents in the pudendal or tibial nerve. Cats anesthetized with α-chloralose were studied after acute spinal cord transection at the thoracic T9/T10 level. Dilute (0.25%) acetic acid was used to irritate the bladder, activate nociceptive afferent C-fibers, and trigger spinal reflex bladder contractions (amplitude: 19.3 ± 2.9 cmH2O). Hexamethonium (a ganglionic blocker, intravenously) significantly (P < 0.01) reduced the amplitude of the reflex bladder contractions to 8.5 ± 1.9 cmH2O. Injection of lidocaine (2%, 1-2 ml) into the sacral spinal cord or transection of the sacral spinal roots and spinal cord further reduced the contraction amplitude to 4.2 ± 1.3 cmH2O. Pudendal nerve stimulation (PNS) at frequencies of 0.5-5 Hz and 40 Hz but not at 10-20 Hz inhibited reflex bladder contractions, whereas tibial nerve stimulation (TNS) failed to inhibit bladder contractions at all tested frequencies (0.5-40 Hz). These results indicate that PNS inhibition of nociceptive afferent C-fiber-mediated spinal reflex bladder contractions can occur at the spinal level in the absence of supraspinal pathways, but TNS inhibition requires supraspinal pathways. In addition, this study shows, for the first time, that after acute spinal cord transection reflex bladder contractions can be triggered by activating nociceptive bladder afferent C-fibers using acetic acid irritation. Understanding the sites of action for PNS or TNS inhibition is important for the clinical application of pudendal or tibial neuromodulation to treat bladder dysfunctions. PMID:25056352

  9. Human umbilical cord blood mononuclear cells and chorionic plate-derived mesenchymal stem cells promote axon survival in a rat model of optic nerve crush injury

    OpenAIRE

    CHUNG, SOKJOONG; RHO, SEUNGSOO; KIM, GIJIN; Kim, So-Ra; Baek, Kwang-Hyun; KANG, MYUNGSEO; Lew, Helen

    2016-01-01

    The use of mesenchymal stem cells (MSCs) in cell therapy in regenerative medicine has great potential, particularly in the treatment of nerve injury. Umbilical cord blood (UCB) reportedly contains stem cells, which have been widely used as a hematopoietic source and may have therapeutic potential for neurological impairment. Although ongoing research is dedicated to the management of traumatic optic nerve injury using various measures, novel therapeutic strategies based on the complex underly...

  10. Nitric oxide modulates bladder afferent nerve activity in the in vitro urinary bladder-pelvic nerve preparation from rats with cyclophosphamide induced cystitis.

    Science.gov (United States)

    Yu, Yongbei; de Groat, William C

    2013-01-15

    Effects of a nitric oxide (NO) donor (SNAP), NO substrate (l-arginine), and NO synthase inhibitor (l-NAME) on bladder afferent nerve (BAN) activity were studied in an in vitro bladder-pelvic nerve preparation from untreated or cyclophosphamide (CYP) treated rats. Distension of the bladder induced phasic bladder contractions (PBC) that were accompanied by multiunit afferent firing. Intravesical administration of SNAP (2mM) which did not change the amplitude of PBC significantly decreased peak afferent firing from 79 ± 15 spikes/s to 44 ± 8 spikes/s in CYP pretreated but not untreated preparations. In CYP treated preparations SNAP also decreased by 33-55% BAN firing induced by isotonic distension of the bladder at 10-40 cmH(2)O pressures. Electrical stimulation on the surface of the bladder elicited action potentials (AP) in BAN. SNAP significantly increased the voltage threshold by 75% (pbladder hyperactivity induced by pathological conditions. PMID:23063886

  11. The Use of Fiber-Reinforced Scaffolds Cocultured with Schwann Cells and Vascular Endothelial Cells to Repair Rabbit Sciatic Nerve Defect with Vascularization

    Directory of Open Access Journals (Sweden)

    Hongyang Gao

    2013-01-01

    Full Text Available To explore the feasibility of biodegradable fiber-reinforced 3D scaffolds with satisfactory mechanical properties for the repair of long-distance sciatic nerve defect in rabbits and effects of vascularized graft in early stage on the recovery of neurological function, Schwann cells and vascular endothelial cells were cocultured in the fiber-reinforced 3D scaffolds. Experiment group which used prevascularized nerve complex for the repair of sciatic nerve defect and control group which only cultured with Schwann cells were set. The animals in both groups underwent electromyography to show the status of the neurological function recovery at 4, 8, and 16 weeks after the surgery. Sciatic nerve regeneration and myelination were observed under the light microscope and electron microscope. Myelin sheath thickness, axonal diameter, and number of myelinated nerve fiber were quantitatively analyzed using image analysis system. The recovery of foot ulcer, the velocity of nerve conduction, the number of regenerating nerve fiber, and the recovery of ultrastructure were increased in the experimental group than those in the control group. Prevascularized tissue engineered fiber-reinforced 3D scaffolds for the repair of sciatic nerve defects in rabbits can effectively promote the recovery of neurological function.

  12. The use of fiber-reinforced scaffolds cocultured with Schwann cells and vascular endothelial cells to repair rabbit sciatic nerve defect with vascularization.

    Science.gov (United States)

    Gao, Hongyang; You, Yang; Zhang, Guoping; Zhao, Feng; Sha, Ziyi; Shen, Yong

    2013-01-01

    To explore the feasibility of biodegradable fiber-reinforced 3D scaffolds with satisfactory mechanical properties for the repair of long-distance sciatic nerve defect in rabbits and effects of vascularized graft in early stage on the recovery of neurological function, Schwann cells and vascular endothelial cells were cocultured in the fiber-reinforced 3D scaffolds. Experiment group which used prevascularized nerve complex for the repair of sciatic nerve defect and control group which only cultured with Schwann cells were set. The animals in both groups underwent electromyography to show the status of the neurological function recovery at 4, 8, and 16 weeks after the surgery. Sciatic nerve regeneration and myelination were observed under the light microscope and electron microscope. Myelin sheath thickness, axonal diameter, and number of myelinated nerve fiber were quantitatively analyzed using image analysis system. The recovery of foot ulcer, the velocity of nerve conduction, the number of regenerating nerve fiber, and the recovery of ultrastructure were increased in the experimental group than those in the control group. Prevascularized tissue engineered fiber-reinforced 3D scaffolds for the repair of sciatic nerve defects in rabbits can effectively promote the recovery of neurological function. PMID:24490158

  13. Adenoviral-mediated glial cell line-derived neurotrophic factor gene transfer has a protective effect on sciatic nerve following constriction-induced spinal cord injury.

    Science.gov (United States)

    Chou, An-Kuo; Yang, Ming-Chang; Tsai, Hung-Pei; Chai, Chee-Yin; Tai, Ming-Hong; Kwan, Aij-Li; Hong, Yi-Ren

    2014-01-01

    Neuropathic pain due to peripheral nerve injury may be associated with abnormal central nerve activity. Glial cell-line-derived neurotrophic factor (GDNF) can help attenuate neuropathic pain in different animal models of nerve injury. However, whether GDNF can ameliorate neuropathic pain in the spinal cord dorsal horn (SCDH) in constriction-induced peripheral nerve injury remains unknown. We investigated the therapeutic effects of adenoviral-mediated GDNF on neuropathic pain behaviors, microglial activation, pro-inflammatory cytokine expression and programmed cell death in a chronic constriction injury (CCI) nerve injury animal model. In this study, neuropathic pain was produced by CCI on the ipsilateral SCDH. Mechanical allodynia was examined with von Frey filaments and thermal sensitivity was tested using a plantar test apparatus post-operatively. Target proteins GDNF-1, GDNFRa-1, MMP2, MMP9, p38, phospho-p38, ED1, IL6, IL1β, AIF, caspase-9, cleaved caspase-9, caspase-3, cleaved caspase-3, PARP, cleaved PARP, SPECTRIN, cleaved SPECTRIN, Beclin-1, PKCσ, PKCγ, iNOS, eNOS and nNOS were detected. Microglial activity was measured by observing changes in immunoreactivity with OX-42. NeuN and TUNEL staining were used to reveal whether apoptosis was attenuated by GDNF. Results showed that administrating GDNF began to attenuate both allodynia and thermal hyperalgesia at day 7. CCI-rats were found to have lower GDNF and GDNFRa-1 expression compared to controls, and GDNF re-activated their expression. Also, GDNF significantly down-regulated CCI-induced protein expression except for MMP2, eNOS and nNOS, indicating that the protective action of GDNF might be associated with anti-inflammation and prohibition of microglia activation. Immunocytochemistry staining showed that GDNF reduced CCI-induced neuronal apoptosis. In sum, GDNF enhanced the neurotrophic effect by inhibiting microglia activation and cytokine production via p38 and PKC signaling. GDNF could be a good

  14. Facial Nerve Palsy: An Unusual Presenting Feature of Small Cell Lung Cancer

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    Ozcan Yildiz

    2011-01-01

    Full Text Available Lung cancer is the second most common type of cancer in the world and is the most common cause of cancer-related death in men and women; it is responsible for 1.3 million deaths annually worldwide. It can metastasize to any organ. The most common site of metastasis in the head and neck region is the brain; however, it can also metastasize to the oral cavity, gingiva, tongue, parotid gland and lymph nodes. This article reports a case of small cell lung cancer presenting with metastasis to the facial nerve.

  15. Involvement of TRPM2 in peripheral nerve injury-induced infiltration of peripheral immune cells into the spinal cord in mouse neuropathic pain model.

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    Kouichi Isami

    Full Text Available Recent evidence suggests that transient receptor potential melastatin 2 (TRPM2 expressed in immune cells plays an important role in immune and inflammatory responses. We recently reported that TRPM2 expressed in macrophages and spinal microglia contributes to the pathogenesis of inflammatory and neuropathic pain aggravating peripheral and central pronociceptive inflammatory responses in mice. To further elucidate the contribution of TRPM2 expressed by peripheral immune cells to neuropathic pain, we examined the development of peripheral nerve injury-induced neuropathic pain and the infiltration of immune cells (particularly macrophages into the injured nerve and spinal cord by using bone marrow (BM chimeric mice by crossing wildtype (WT and TRPM2-knockout (TRPM2-KO mice. Four types of BM chimeric mice were prepared, in which irradiated WT or TRPM2-KO recipient mice were transplanted with either WT-or TRPM2-KO donor mouse-derived green fluorescence protein-positive (GFP(+ BM cells (TRPM2(BM+/Rec+, TRPM2(BM-/Rec+, TRPM2(BM+/Rec-, and TRPM2(BM-/Rec- mice. Mechanical allodynia induced by partial sciatic nerve ligation observed in TRPM2(BM+/Rec+ mice was attenuated in TRPM2(BM-/Rec+, TRPM2(BM+/Rec-, and TRPM2(BM-/Rec- mice. The numbers of GFP(+ BM-derived cells and Iba1/GFP double-positive macrophages in the injured sciatic nerve did not differ among chimeric mice 14 days after the nerve injury. In the spinal cord, the number of GFP(+ BM-derived cells, particularly GFP/Iba1 double-positive macrophages, was significantly decreased in the three TRPM2-KO chimeric mouse groups compared with TRPM2(BM+/Rec+ mice. However, the numbers of GFP(-/Iba1(+ resident microglia did not differ among chimeric mice. These results suggest that TRPM2 plays an important role in the infiltration of peripheral immune cells, particularly macrophages, into the spinal cord, rather than the infiltration of peripheral immune cells into the injured nerves and activation of spinal

  16. Channels Active in the Excitability of Nerves and Skeletal Muscles across the Neuromuscular Junction: Basic Function and Pathophysiology

    Science.gov (United States)

    Goodman, Barbara E.

    2008-01-01

    Ion channels are essential for the basic physiological function of excitable cells such as nerve, skeletal, cardiac, and smooth muscle cells. Mutations in genes that encode ion channels have been identified to cause various diseases and disorders known as channelopathies. An understanding of how individual ion channels are involved in the…

  17. Functional recoveries of sciatic nerve regeneration by combining chitosan-coated conduit and neurosphere cells induced from adipose-derived stem cells.

    Science.gov (United States)

    Hsueh, Yuan-Yu; Chang, Ya-Ju; Huang, Tzu-Chieh; Fan, Shih-Chen; Wang, Duo-Hsiang; Chen, Jia-Jin Jason; Wu, Chia-Ching; Lin, Sheng-Che

    2014-02-01

    Suboptimal repair occurs in a peripheral nerve gap, which can be partially restored by bridging the gap with various biosynthetic conduits or cell-based therapy. In this study, we developed a combination of chitosan coating approach to induce neurosphere cells from human adipose-derived stem cells (ASCs) on chitosan-coated plate and then applied these cells to the interior of a chitosan-coated silicone tube to bridge a 10-mm gap in a rat sciatic nerve. Myelin sheath degeneration and glial scar formation were discovered in the nerve bridged by the silicone conduit. By using a single treatment of chitosan-coated conduit or neurosphere cell therapy, the nerve gap was partially recovered after 6 weeks of surgery. Substantial improvements in nerve regeneration were achieved by combining neurosphere cells and chitosan-coated conduit based on the increase of myelinated axons density and myelin thickness, gastrocnemius muscle weight and muscle fiber diameter, and step and stride lengths from gait analysis. High expressions of interleukin-1β and leukotriene B4 receptor 1 in the intra-neural scarring caused by using silicone conduits revealed that the inflammatory mechanism can be inhibited when the conduit is coated with chitosan. This study demonstrated that the chitosan-coated surface performs multiple functions that can be used to induce neurosphere cells from ASCs and to facilitate nerve regeneration in combination with a cells-assisted coated conduit. PMID:24360575

  18. Transgenic inhibition of astroglial NF-κB protects from optic nerve damage and retinal ganglion cell loss in experimental optic neuritis

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    Brambilla Roberta

    2012-09-01

    Full Text Available Abstract Background Optic neuritis is an acute, demyelinating neuropathy of the optic nerve often representing the first appreciable symptom of multiple sclerosis. Wallerian degeneration of irreversibly damaged optic nerve axons leads to death of retinal ganglion cells, which is the cause of permanent visual impairment. Although the specific mechanisms responsible for triggering these events are unknown, it has been suggested that a key pathological factor is the activation of immune-inflammatory processes secondary to leukocyte infiltration. However, to date, there is no conclusive evidence to support such a causal role for infiltrating peripheral immune cells in the etiopathology of optic neuritis. Methods To dissect the contribution of the peripheral immune-inflammatory response versus the CNS-specific inflammatory response in the development of optic neuritis, we analyzed optic nerve and retinal ganglion cells pathology in wild-type and GFAP-IκBα-dn transgenic mice, where NF-κB is selectively inactivated in astrocytes, following induction of EAE. Results We found that, in wild-type mice, axonal demyelination in the optic nerve occurred as early as 8 days post induction of EAE, prior to the earliest signs of leukocyte infiltration (20 days post induction. On the contrary, GFAP-IκBα-dn mice were significantly protected and showed a nearly complete prevention of axonal demyelination, as well as a drastic attenuation in retinal ganglion cell death. This correlated with a decrease in the expression of pro-inflammatory cytokines, chemokines, adhesion molecules, as well as a prevention of NAD(PH oxidase subunit upregulation. Conclusions Our results provide evidence that astrocytes, not infiltrating immune cells, play a key role in the development of optic neuritis and that astrocyte-mediated neurotoxicity is dependent on activation of a transcriptional program regulated by NF-κB. Hence, interventions targeting the NF-κB transcription

  19. NF-κB Regulates B-Cell-Derived Nerve Growth Factor Expression

    Institute of Scientific and Technical Information of China (English)

    Klaus Heese; Noriko Inoue; Tohru Sawada

    2006-01-01

    In the mammalian brain, four neurotrophins have been identified: nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3) and neurotrophin-4/5 (NT-4/5). NGF exerts an important role in the development and functions of the central and peripheral nervous system. However, it has recently been documented that several types of immune cells, such as mast cells, lymphocytes, basophils and eosinophils, produce,store and release NGF. Accumulating preclinical and clinical data indicate that dysfunctions of NGF and the other neurotrophins may contribute to impaired immune responses and concentration of NGF frequently correlates with disease severity. Thus, the aim of this study was to elucidate the potential signaling mechanisms of cytokineneurotrophins interactions contributing to increased NGF levels. Our data show that the transcription factorNF-κB plays a pivotal role in regulating B-cell-derived NGF expression.

  20. Analysis of protein phosphorylation in nerve terminal reveals extensive changes in active zone proteins upon exocytosis.

    Science.gov (United States)

    Kohansal-Nodehi, Mahdokht; Chua, John Je; Urlaub, Henning; Jahn, Reinhard; Czernik, Dominika

    2016-01-01

    Neurotransmitter release is mediated by the fast, calcium-triggered fusion of synaptic vesicles with the presynaptic plasma membrane, followed by endocytosis and recycling of the membrane of synaptic vesicles. While many of the proteins governing these processes are known, their regulation is only beginning to be understood. Here we have applied quantitative phosphoproteomics to identify changes in phosphorylation status of presynaptic proteins in resting and stimulated nerve terminals isolated from the brains of Wistar rats. Using rigorous quantification, we identified 252 phosphosites that are either up- or downregulated upon triggering calcium-dependent exocytosis. Particularly pronounced were regulated changes of phosphosites within protein constituents of the presynaptic active zone, including bassoon, piccolo, and RIM1. Additionally, we have mapped kinases and phosphatases that are activated upon stimulation. Overall, our study provides a snapshot of phosphorylation changes associated with presynaptic activity and provides a foundation for further functional analysis of key phosphosites involved in presynaptic plasticity. PMID:27115346

  1. Methylcobalamin promotes the differentiation of Schwann cells and remyelination in lysophosphatidylcholine-induced demyelination of the rat sciatic nerve

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    Shunsuke eNishimoto

    2015-08-01

    Full Text Available Schwann cells (SCs are constituents of the peripheral nervous system. The differentiation of SCs in injured peripheral nerves is critical for regeneration after injury. Methylcobalamin (MeCbl is a vitamin B12 analog that is necessary for the maintenance of the peripheral nervous system. In this study, we estimated the effect of MeCbl on SCs. We showed that MeCbl downregulated the activity of Erk1/2 and promoted the expression of the myelin basic protein in SCs. In a dorsal root ganglion neuron–SC coculture system, myelination was promoted by MeCbl. In a focal demyelination rat model, MeCbl promoted remyelination and motor and sensory functional regeneration. MeCbl promoted the in vitro differentiation of SCs and in vivo myelination in a rat demyelination model and may be a novel therapy for several types of nervous disorders.

  2. Acute electromyostimulation decreases muscle sympathetic nerve activity in patients with advanced chronic heart failure (EMSICA Study.

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    Marc Labrunée

    Full Text Available BACKGROUND: Muscle passive contraction of lower limb by neuromuscular electrostimulation (NMES is frequently used in chronic heart failure (CHF patients but no data are available concerning its action on sympathetic activity. However, Transcutaneous Electrical Nerve Stimulation (TENS is able to improve baroreflex in CHF. The primary aim of the present study was to investigate the acute effect of TENS and NMES compared to Sham stimulation on sympathetic overactivity as assessed by Muscle Sympathetic Nerve Activity (MSNA. METHODS: We performed a serie of two parallel, randomized, double blinded and sham controlled protocols in twenty-two CHF patients in New York Heart Association (NYHA Class III. Half of them performed stimulation by TENS, and the others tested NMES. RESULTS: Compare to Sham stimulation, both TENS and NMES are able to reduce MSNA (63.5 ± 3.5 vs 69.7 ± 3.1 bursts / min, p < 0.01 after TENS and 51.6 ± 3.3 vs 56.7 ± 3.3 bursts / min, p < 0, 01 after NMES. No variation of blood pressure, heart rate or respiratory parameters was observed after stimulation. CONCLUSION: The results suggest that sensory stimulation of lower limbs by electrical device, either TENS or NMES, could inhibit sympathetic outflow directed to legs in CHF patients. These properties could benefits CHF patients and pave the way for a new non-pharmacological approach of CHF.

  3. Neuroprotective Activity of Thioctic Acid in Central Nervous System Lesions Consequent to Peripheral Nerve Injury

    Directory of Open Access Journals (Sweden)

    Daniele Tomassoni

    2013-01-01

    Full Text Available Peripheral neuropathies are heterogeneous disorders presenting often with hyperalgesia and allodynia. This study has assessed if chronic constriction injury (CCI of sciatic nerve is accompanied by increased oxidative stress and central nervous system (CNS changes and if these changes are sensitive to treatment with thioctic acid. Thioctic acid is a naturally occurring antioxidant existing in two optical isomers (+- and (−-thioctic acid and in the racemic form. It has been proposed for treating disorders associated with increased oxidative stress. Sciatic nerve CCI was made in spontaneously hypertensive rats (SHRs and in normotensive reference cohorts. Rats were untreated or treated intraperitoneally for 14 days with (+/−-, (+-, or (−-thioctic acid. Oxidative stress, astrogliosis, myelin sheets status, and neuronal injury in motor and sensory cerebrocortical areas were assessed. Increase of oxidative stress markers, astrogliosis, and neuronal damage accompanied by a decreased expression of neurofilament were observed in SHR. This phenomenon was more pronounced after CCI. Thioctic acid countered astrogliosis and neuronal damage, (+-thioctic acid being more active than (+/−- or (−-enantiomers. These findings suggest a neuroprotective activity of thioctic acid on CNS lesions consequent to CCI and that the compound may represent a therapeutic option for entrapment neuropathies.

  4. Analysis of spatial relationships in three dimensions: tools for the study of nerve cell patterning

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    Raven Mary A

    2008-07-01

    Full Text Available Abstract Background Multiple technologies have been brought to bear on understanding the three-dimensional morphology of individual neurons and glia within the brain, but little progress has been made on understanding the rules controlling cellular patterning. We describe new matlab-based software tools, now available to the scientific community, permitting the calculation of spatial statistics associated with 3D point patterns. The analyses are largely derived from the Delaunay tessellation of the field, including the nearest neighbor and Voronoi domain analyses, and from the spatial autocorrelogram. Results Our tools enable the analysis of the spatial relationship between neurons within the central nervous system in 3D, and permit the modeling of these fields based on lattice-like simulations, and on simulations of minimal-distance spacing rules. Here we demonstrate the utility of our analysis methods to discriminate between two different simulated neuronal populations. Conclusion Together, these tools can be used to reveal the presence of nerve cell patterning and to model its foundation, in turn informing on the potential developmental mechanisms that govern its establishment. Furthermore, in conjunction with analyses of dendritic morphology, they can be used to determine the degree of dendritic coverage within a volume of tissue exhibited by mature nerve cells.

  5. Human umbilical cord blood stem cells and brain-derived neurotrophic factor for optic nerve injury:a biomechanical evaluation

    Institute of Scientific and Technical Information of China (English)

    Zhong-jun Zhang; Ya-jun Li; Xiao-guang Liu; Feng-xiao Huang; Tie-jun Liu; Dong-mei Jiang; Xue-man Lv; Min Luo

    2015-01-01

    Treatment for optic nerve injury by brain-derived neurotrophic factor or the transplantation of human umbilical cord blood stem cells has gained progress, but analysis by biomechanical indicators is rare. Rabbit models of optic nerve injury were established by a clamp. At 7 days after injury, the vitreous body received a one-time injection of 50 μg brain-derived neurotrophic factor or 1 × 106 human umbilical cord blood stem cells. After 30 days, the maximum load, max-imum stress, maximum strain, elastic limit load, elastic limit stress, and elastic limit strain had clearly improved in rabbit models of optical nerve injury after treatment with brain-derived neu-rotrophic factor or human umbilical cord blood stem cells. The damage to the ultrastructure of the optic nerve had also been reduced. These ifndings suggest that human umbilical cord blood stem cells and brain-derived neurotrophic factor effectively repair the injured optical nerve, im-prove biomechanical properties, and contribute to the recovery after injury.

  6. Immunobiology of Facial Nerve Repair and Regeneration

    Institute of Scientific and Technical Information of China (English)

    QUAN Shi-ming; GAO Zhi-qiang

    2006-01-01

    Immunobiological study is a key to revealing the important basis of facial nerve repair and regeneration for both research and development of clinic treatments. The microenvironmental changes around an injuried facial motoneuron, i.e., the aggregation and expression of various types of immune cells and molecules in a dynamic equilibrium, impenetrate from the start to the end of the repair of an injured facial nerve. The concept of "immune microenvironment for facial nerve repair and regeneration", mainly concerns with the dynamic exchange between expression and regulation networks and a variaty of immune cells and immune molecules in the process of facial nerve repair and regeneration for the maintenance of a immune microenvironment favorable for nerve repair.Investigation on microglial activation and recruitment, T cell behavior, cytokine networks, and immunological cellular and molecular signaling pathways in facial nerve repair and regeneration are the current hot spots in the research on immunobiology of facial nerve injury. The current paper provides a comprehensive review of the above mentioned issues. Research of these issues will eventually make immunological interventions practicable treatments for facial nerve injury in the clinic.

  7. Defective peripheral nerve development is linked to abnormal architecture and metabolic activity of adipose tissue in Nscl-2 mutant mice.

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    Karen Ruschke

    Full Text Available BACKGROUND: In mammals the interplay between the peripheral nervous system (PNS and adipose tissue is widely unexplored. We have employed mice, which develop an adult onset of obesity due to the lack the neuronal specific transcription factor Nscl-2 to investigate the interplay between the nervous system and white adipose tissue (WAT. METHODOLOGY: Changes in the architecture and innervation of WAT were compared between wildtype, Nscl2-/-, ob/ob and Nscl2-/-//ob/ob mice using morphological methods, immunohistochemistry and flow cytometry. Metabolic alterations in mutant mice and in isolated cells were investigated under basal and stimulated conditions. PRINCIPAL FINDINGS: We found that Nscl-2 mutant mice show a massive reduction of innervation of white epididymal and paired subcutaneous inguinal fat tissue including sensory and autonomic nerves as demonstrated by peripherin and neurofilament staining. Reduction of innervation went along with defects in the formation of the microvasculature, accumulation of cells of the macrophage/preadipocyte lineage, a bimodal distribution of the size of fat cells, and metabolic defects of isolated adipocytes. Despite a relative insulin resistance of white adipose tissue and isolated Nscl-2 mutant adipocytes the serum level of insulin in Nscl-2 mutant mice was only slightly increased. CONCLUSIONS: We conclude that the reduction of the innervation and vascularization of WAT in Nscl-2 mutant mice leads to the increase of preadipocyte/macrophage-like cells, a bimodal distribution of the size of adipocytes in WAT and an altered metabolic activity of adipocytes.

  8. Interfaces between dendritic cells, other immune cells, and nerve fibres in mouse Peyer's patches: potential sites for neuroinvasion in prion diseases.

    Science.gov (United States)

    Defaweux, Valérie; Dorban, Gauthier; Demonceau, Caroline; Piret, Joëlle; Jolois, Olivier; Thellin, Olivier; Thielen, Caroline; Heinen, Ernst; Antoine, Nadine

    2005-01-01

    In this study, we examined where immune cells and nerve fibres are located in mouse Peyer's patches, with a view to identifying potential sites for neuroinvasion by prions. Special attention was paid to dendritic cells, viewed as candidate transporters of infectious prion. Double immunofluorescence labellings with anti-CD11c antibody and marker for other immune cells (B cells, T cells, follicular dendritic cells) were carried out and analysed by confocal microscopy on Peyer's patch cryosections. To reveal the extensive ganglionated networks of the myenteric and submucosal plexi and the sparse meshworks of nerve strands, we used antibodies directed against different neurofilament subunits or against glial fibrillary acidic protein. In the suprafollicular dome, dendritic cells connect, via their cytoplasmic extensions, enterocytes with M cells of the follicle-associated epithelium. They are also close to B and T cells. Nerve fibres are detected in the suprafollicular dome, notably in contact with dendritic cells. Similar connections between dendritic cells, T cells, and nerve fibres are seen in the interfollicular region. Germinal centres are not innervated; inside them dendritic cells establish contacts with follicular dendritic cells and with B cells. After immunolabelling of normal prion protein, dendritic cells of the suprafollicular dome are intensely positive labelled. PMID:15816033

  9. Urokinase plasminogen receptor and the fibrinolytic complex play a role in nerve repair after nerve crush in mice, and in human neuropathies.

    Directory of Open Access Journals (Sweden)

    Cristina Rivellini

    Full Text Available Remodeling of extracellular matrix (ECM is a critical step in peripheral nerve regeneration. In fact, in human neuropathies, endoneurial ECM enriched in fibrin and vitronectin associates with poor regeneration and worse clinical prognosis. Accordingly in animal models, modification of the fibrinolytic complex activity has profound effects on nerve regeneration: high fibrinolytic activity and low levels of fibrin correlate with better nerve regeneration. The urokinase plasminogen receptor (uPAR is a major component of the fibrinolytic complex, and binding to urokinase plasminogen activator (uPA promotes fibrinolysis and cell movement. uPAR is expressed in peripheral nerves, however, little is known on its potential function on nerve development and regeneration. Thus, we investigated uPAR null mice and observed that uPAR is dispensable for nerve development, whereas, loss of uPAR affects nerve regeneration. uPAR null mice showed reduced nerve repair after sciatic nerve crush. This was a consequence of reduced fibrinolytic activity and increased deposition of endoneurial fibrin and vitronectin. Exogenous fibrinolysis in uPAR null mice rescued nerve repair after sciatic nerve crush. Finally, we measured the fibrinolytic activity in sural nerve biopsies from patients with peripheral neuropathies. We showed that neuropathies with defective regeneration had reduced fibrinolytic activity. On the contrary, neuropathies with signs of active regeneration displayed higher fibrinolytic activity. Overall, our results suggest that enforced fibrinolysis may facilitate regeneration and outcome of peripheral neuropathies.

  10. Evoked bioelectrical activity of efferent fibers of the sciatic nerve of white rats in experimental menopause

    Directory of Open Access Journals (Sweden)

    Rodinsky A.G.

    2016-03-01

    Full Text Available The aim of our work was analysis of the bioelectrical activity of efferent fibers of the sciatic nerve in experimental menopause condition. Experiments were performed on 25 female white rats, divided into experimental and control groups. Menopause was modeled by total ovariohysterectomy. In 120 days after modeling we had recorded evoked action potentials of fibers of isolated ventral root L5 induced by stimulation of sciatic nerve with rectangular pulses. Threshold, chronaxia, latency, amplitude and duration of the action potential (AP were analysed. Refractory phenomenon was investigated by applying paired stimuli at intervals of 2 to 20 ms. In the context of long-term hypoestrogenemy threshold of AP appearance was 55,32±7,69%, chronaxy – 115,09±2,67%, latent period – 112,62±1,74% as compared with the control animals (p<0.01. In conditions of paired stimuli applying the amplitude of response to the testing stimulus in animals with ovariohysterectomy at intervals 3 and 4 ms was 61,25±36,45% and 53,48±18,64% (p<0.05 respectively.

  11. Differentiation of mesenchymal stem cells into neuronal cells on fetal bovine acellular dermal matrix as a tissue engineered nerve scaffold

    Institute of Scientific and Technical Information of China (English)

    Yuping Feng; Jiao Wang; Shixin Ling; Zhuo Li; Mingsheng Li; Qiongyi Li; Zongren Ma; Sijiu Yu

    2014-01-01

    The purpose of this study was to assess fetal bovine acellular dermal matrix as a scaffold for supporting the differentiation of bone marrow mesenchymal stem cells into neural cells fol-lowing induction with neural differentiation medium. We performed long-term, continuous observation of cell morphology, growth, differentiation, and neuronal development using several microscopy techniques in conjunction with immunohistochemistry. We examined speciifc neu-ronal proteins and Nissl bodies involved in the differentiation process in order to determine the neuronal differentiation of bone marrow mesenchymal stem cells. The results show that bone marrow mesenchymal stem cells that differentiate on fetal bovine acellular dermal matrix display neuronal morphology with unipolar and bi/multipolar neurite elongations that express neuro-nal-speciifc proteins, includingβIII tubulin. The bone marrow mesenchymal stem cells grown on fetal bovine acellular dermal matrix and induced for long periods of time with neural differen-tiation medium differentiated into a multilayered neural network-like structure with long nerve ifbers that was composed of several parallel microifbers and neuronal cells, forming a complete neural circuit with dendrite-dendrite to axon-dendrite to dendrite-axon synapses. In addition, growth cones with filopodia were observed using scanning electron microscopy. Paraffin sec-tioning showed differentiated bone marrow mesenchymal stem cells with the typical features of neuronal phenotype, such as a large, round nucleus and a cytoplasm full of Nissl bodies. The data suggest that the biological scaffold fetal bovine acellular dermal matrix is capable of supporting human bone marrow mesenchymal stem cell differentiation into functional neurons and the subsequent formation of tissue engineered nerve.

  12. Leptin differentially increases sympathetic nerve activity and its baroreflex regulation in female rats: role of oestrogen.

    Science.gov (United States)

    Shi, Zhigang; Brooks, Virginia L

    2015-04-01

    Obesity and hypertension are commonly associated, and activation of the sympathetic nervous system is considered to be a major contributor, at least in part due to the central actions of leptin. However, while leptin increases sympathetic nerve activity (SNA) in males, whether leptin is equally effective in females is unknown. Here, we show that intracerebroventricular (i.c.v.) leptin increases lumbar (LSNA) and renal (RSNA) SNA and baroreflex control of LSNA and RSNA in α-chloralose anaesthetized female rats, but only during pro-oestrus. In contrast, i.c.v. leptin increased basal and baroreflex control of splanchnic SNA (SSNA) and heart rate (HR) in rats in both the pro-oestrus and dioestrus states. The effects of leptin on basal LSNA, RSNA, SSNA and HR were similar in males and pro-oestrus females; however, i.c.v. leptin increased mean arterial pressure (MAP) only in males. Leptin did not alter LSNA or HR in ovariectomized rats, but its effects were normalized with 4 days of oestrogen treatment. Bilateral nanoinjection of SHU9119 into the paraventricular nucleus of the hypothalamus (PVN), to block α-melanocyte-stimulating hormone (α-MSH) type 3 and 4 receptors, decreased LSNA in leptin-treated pro-oestrus but not dioestrus rats. Unlike leptin, i.c.v. insulin infusion increased basal and baroreflex control of LSNA and HR similarly in pro-oestrus and dioestrus rats; these responses did not differ from those in male rats. We conclude that, in female rats, leptin's stimulatory effects on SNA are differentially enhanced by oestrogen, at least in part via an increase in α-MSH activity in the PVN. These data further suggest that the actions of leptin and insulin to increase the activity of various sympathetic nerves occur via different neuronal pathways or cellular mechanisms. These results may explain the poor correlation in females of SNA with adiposity, or of MAP with leptin. PMID:25398524

  13. Maslinic Acid Protected PC12 Cells Differentiated by Nerve Growth Factor against β-Amyloid-Induced Apoptosis.

    Science.gov (United States)

    Yang, Yu-wan; Tsai, Chia-wen; Mong, Mei-chin; Yin, Mei-chin

    2015-12-01

    β-Amyloid peptide (Abeta) was used to induce apoptosis in PC12 cells differentiated by nerve growth factor, and the protective activities of maslinic acid (MA) at 2-16 μM were examined. Abeta treatment lowered Bcl-2 expression, raised Bax expression, and decreased cell viability. MA pretreatments decreased Bax expression, raised the Bcl-2/Bax ratio, and increased cell viability. MA pretreatments retained glutathione content and decreased subsequent Abeta-induced release of reactive oxygen species, tumor necrosis factor-α, interleukin (IL)-1β, and IL-6. Abeta treatment up-regulated protein expression of p47(phox), gp91(phox), mitogen-activated protein kinase, advanced glycation end product receptor (RAGE), and nuclear factor-κ B (NF-κB). MA pretreatments at 2-16 μM suppressed the expression of proteins including gp91(phox), p47(phox), p-p38, and NF-κB p65, at 4-16 μM down-regulated RAGE and NF-κB p50 expression, and at 8 and 16 μM reduced p-ERK1/2 expression. These novel findings suggest that maslinic acid is a potent compound against Abeta-induced cytotoxicity.

  14. Reconstruction of Multiple Facial Nerve Branches Using Skeletal Muscle-Derived Multipotent Stem Cell Sheet-Pellet Transplantation.

    Directory of Open Access Journals (Sweden)

    Kosuke Saito

    Full Text Available Head and neck cancer is often diagnosed at advanced stages, and surgical resection with wide margins is generally indicated, despite this treatment being associated with poor postoperative quality of life (QOL. We have previously reported on the therapeutic effects of skeletal muscle-derived multipotent stem cells (Sk-MSCs, which exert reconstitution capacity for muscle-nerve-blood vessel units. Recently, we further developed a 3D patch-transplantation system using Sk-MSC sheet-pellets. The aim of this study is the application of the 3D Sk-MSC transplantation system to the reconstitution of facial complex nerve-vascular networks after severe damage. Mouse experiments were performed for histological analysis and rats were used for functional examinations. The Sk-MSC sheet-pellets were prepared from GFP-Tg mice and SD rats, and were transplanted into the facial resection model (ST. Culture medium was transplanted as a control (NT. In the mouse experiment, facial-nerve-palsy (FNP scoring was performed weekly during the recovery period, and immunohistochemistry was used for the evaluation of histological recovery after 8 weeks. In rats, contractility of facial muscles was measured via electrical stimulation of facial nerves root, as the marker of total functional recovery at 8 weeks after transplantation. The ST-group showed significantly higher FNP (about three fold scores when compared to the NT-group after 2-8 weeks. Similarly, significant functional recovery of whisker movement muscles was confirmed in the ST-group at 8 weeks after transplantation. In addition, engrafted GFP+ cells formed complex branches of nerve-vascular networks, with differentiation into Schwann cells and perineurial/endoneurial cells, as well as vascular endothelial and smooth muscle cells. Thus, Sk-MSC sheet-pellet transplantation is potentially useful for functional reconstitution therapy of large defects in facial nerve-vascular networks.

  15. Human umbilical cord blood-derived mesenchymal stem cells promote regeneration of crush-injured rat sciatic nerves

    Institute of Scientific and Technical Information of China (English)

    Mi-Ae Sung; Jong-Ho Lee; Hun Jong Jung; Jung-Woo Lee; Jin-Yong Lee; Kang-Mi Pang; Sang Bae Yoo; Mohammad S. Alrashdan; Soung-Min Kim; Jeong Won Jahng

    2012-01-01

    Several studies have demonstrated that human umbilical cord blood-derived mesenchymal stem cells can promote neural regeneration following brain injury. However, the therapeutic effects of human umbilical cord blood-derived mesenchymal stem cells in guiding peripheral nerve regeneration remain poorly understood. This study was designed to investigate the effects of human umbilical cord blood-derived mesenchymal stem cells on neural regeneration using a rat sciatic nerve crush injury model. Human umbilical cord blood-derived mesenchymal stem cells (1 × 106) or a PBS control were injected into the crush-injured segment of the sciatic nerve. Four weeks after cell injection, brain-derived neurotrophic factor and tyrosine kinase receptor B mRNA expression at the lesion site was increased in comparison to control. Furthermore, sciatic function index, Fluoro Gold-labeled neuron counts and axon density were also significantly increased when compared with control. Our results indicate that human umbilical cord blood-derived mesenchymal stem cells promote the functional recovery of crush-injured sciatic nerves.

  16. The role of the chorda tympani nerve in the activation of the rat hypothalamic histaminergic system by leptin.

    Science.gov (United States)

    Morimoto-Ishizuka, T; Yamamoto, Y; Yamatodani, A

    2001-03-01

    A possible pathway through which leptin activates the histaminergic system was studied using in vivo microdialysis in rats. Intraperitoneal injection of leptin (1.3 mg/kg) caused a significant increase in hypothalamic histamine release, however, its intracerebroventricular injection (10 microg/rat) did not cause any significant changes in the release. Furthermore, leptin (1.3 mg/kg) had no effect on histamine release in rats whose chorda tympani nerves, a branch of the facial nerve which mediates taste information, were transected bilaterally. These findings indicate that leptin activates the histaminergic system by the peripheral signal inputs via the chorda tympani resulting in the suppression of food intake.

  17. ATP released by injured neurons activates Schwann cells

    Directory of Open Access Journals (Sweden)

    Samuele eNegro

    2016-05-01

    Full Text Available Injured nerve terminals of neuromuscular junctions (NMJs can regenerate. This remarkable and complex response is governed by molecular signals that are exchanged among the cellular components of this synapse: motor axon nerve terminal (MAT, perisynaptic Schwann cells (PSCs, and muscle fibre. The nature of signals that govern MAT regeneration is ill-known. In the present study the spider toxin α-Latrotoxin has been used as tool to investigate the mechanisms underlying peripheral neuroregeneration. Indeed this neurotoxin induces an acute, specific, localized and fully reversible damage of the presynaptic nerve terminal, and its action mimics the cascade of events that leads to nerve terminal degeneration in injured patients and in many neurodegenerative conditions. Here we provide evidence of an early release by degenerating neurons of ATP as alarm messenger, that contributes to the activation of a series of intracellular pathways within SCs that are crucial for nerve regeneration: Ca2+, cAMP, ERK1/2, and CREB. These results contribute to define the cross-talk taking place among degenerating nerve terminals and PSCs, involved in the functional recovery of the NMJ.

  18. Altered active zones, vesicle pools, nerve terminal conductivity, and morphology during experimental MuSK myasthenia gravis.

    Directory of Open Access Journals (Sweden)

    Vishwendra Patel

    Full Text Available Recent studies demonstrate reduced motor-nerve function during autoimmune muscle-specific tyrosine kinase (MuSK myasthenia gravis (MG. To further understand the basis of motor-nerve dysfunction during MuSK-MG, we immunized female C57/B6 mice with purified rat MuSK ectodomain. Nerve-muscle preparations were dissected and neuromuscular junctions (NMJs studied electrophysiologically, morphologically, and biochemically. While all mice produced antibodies to MuSK, only 40% developed respiratory muscle weakness. In vitro study of respiratory nerve-muscle preparations isolated from these affected mice revealed that 78% of NMJs produced endplate currents (EPCs with significantly reduced quantal content, although potentiation and depression at 50 Hz remained qualitatively normal. EPC and mEPC amplitude variability indicated significantly reduced number of vesicle-release sites (active zones and reduced probability of vesicle release. The readily releasable vesicle pool size and the frequency of large amplitude mEPCs also declined. The remaining NMJs had intermittent (4% or complete (18% failure of neurotransmitter release in response to 50 Hz nerve stimulation, presumably due to blocked action potential entry into the nerve terminal, which may arise from nerve terminal swelling and thinning. Since MuSK-MG-affected muscles do not express the AChR γ subunit, the observed prolongation of EPC decay time was not due to inactivity-induced expression of embryonic acetylcholine receptor, but rather to reduced catalytic activity of acetylcholinesterase. Muscle protein levels of MuSK did not change. These findings provide novel insight into the pathophysiology of autoimmune MuSK-MG.

  19. Leptin into the rostral ventral lateral medulla (RVLM augments renal sympathetic nerve activity and blood pressure

    Directory of Open Access Journals (Sweden)

    Maria J Barnes

    2014-08-01

    Full Text Available Leptin is a hormone released from adipose tissue. While this hormone normally acts to reduce feeding behavior and increase energy expenditure, in obesity, resistance to these effects occurs even though the hormone is released in large amounts. Although leptin no longer works to suppress feeding in the obese, leptin retains its potent effects on other autonomic functions such as blood pressure regulation. Leptin has been associated with hypertension and increased sympathetic autonomic activity. Therefore, leptin is emerging as a major contributor to the hypertensive state observed in obesity. Sympathetic control of blood pressure is maintained principally by autonomic reflex control circuits in the caudal brainstem. The rostral ventral-lateral medulla (RVLM is the primary regulator of the sympathetic nervous system, sending excitatory fibers to sympathetic preganglionic neurons to regulate sympathetic control over resistance vessels and blood pressure. Previous studies from our laboratory have shown that neurons in the ventral lateral medulla express leptin receptors (ObRb. Our present study using pseudo-rabies multi-synaptic retrograde tract tracing and immunohistochemical methods revealed that neurons within the RVLM that send sympathetic projections to the kidney express leptin receptors. Acute microinjection of leptin (1 and 3µg; 40nL into the RVLM evoked a significant increase in Mean Arterial Pressure (MAP and renal sympathetic nerve activity (RSNA. When the 3µg dose of leptin was preceded with a leptin antagonist, (SLAN-4; 1ng, it attenuated the cardiovascular response of leptin. Taken together, these data suggest that leptin’s actions within the RVLM may influence blood pressure and renal sympathetic nerve activity.

  20. Combined use of Y-tube conduits with human umbilical cord stem cells for repairing nerve bifurcation defects

    Directory of Open Access Journals (Sweden)

    Aikeremujiang Muheremu

    2016-01-01

    Full Text Available Given the anatomic complexity at the bifurcation point of a nerve trunk, enforced suturing between stumps can lead to misdirection of nerve axons, thereby resulting in adverse consequences. We assumed that Y-tube conduits injected with human umbilical cord stem cells could be an effective method to solve such problems, but studies focused on the best type of Y-tube conduit remain controversial. Therefore, the present study evaluated the applicability and efficacy of various types of Y-tube conduits containing human umbilical cord stem cells for treating rat femoral nerve defects on their bifurcation points. At 12 weeks after the bridging surgery that included treatment with different types of Y-tube conduits, there were no differences in quadriceps femoris muscle weight or femoral nerve ultrastructure. However, the Y-tube conduit group with longer branches and a short trunk resulted in a better outcome according to retrograde labeling and electrophysiological analysis. It can be concluded from the study that repairing a mixed nerve defect at its bifurcation point with Y-tube conduits, in particular those with long branches and a short trunk, is effective and results in good outcomes.

  1. Nerve growth factor: role in growth, differentiation and controlling cancer cell development.

    Science.gov (United States)

    Aloe, Luigi; Rocco, Maria Luisa; Balzamino, Bijorn Omar; Micera, Alessandra

    2016-01-01

    Recent progress in the Nerve Growth Factor (NGF) research has shown that this factor acts not only outside its classical domain of the peripheral and central nervous system, but also on non-neuronal and cancer cells. This latter observation has led to divergent hypothesis about the role of NGF, its specific distribution pattern within the tissues and its implication in induction as well as progression of carcinogenesis. Moreover, other recent studies have shown that NGF has direct clinical relevance in certain human brain neuron degeneration and a number of human ocular disorders. These studies, by suggesting that NGF is involved in a plethora of physiological function in health and disease, warrant further investigation regarding the true role of NGF in carcinogenesis. Based on our long-lasting experience in the physiopathology of NGF, we aimed to review previous and recent in vivo and in vitro NGF studies on tumor cell induction, progression and arrest. Overall, these studies indicate that the only presence of NGF is unable to generate cell carcinogenesis, both in normal neuronal and non-neuronal cells/tissues. However, it cannot be excluded the possibility that the co-expression of NGF and pro-carcinogenic molecules might open to different consequence. Whether NGF plays a direct or an indirect role in cell proliferation during carcinogenesis remains to demonstrate. PMID:27439311

  2. Spinal cord T-cell infiltration in the spared nerve injury model of neuropathic pain: a time course study

    OpenAIRE

    Clarke C.

    2012-01-01

    Background : Numerous studies have shown that immune cells infiltrate the spinal cord after peripheral nerve injury and that they play a major contribution to sensory hypersensitivity in rodents. In particular, the role of monocyte-derived cells and T lymphocytes seems to be prominent in this process. This exciting new perspective in research on neuropathic pain opens many different areas of work, including the understanding of the function of these cells and how they impact on neural functio...

  3. Differential astroglial responses in the spinal cord of rats submitted to a sciatic nerve double crush treated with local injection of cultured Schwann cell suspension or lesioned spinal cord extract: implications on cell therapy for nerve repair Respostas astrocitárias na medula espinal do rato submetido ao esmagamento duplo do nervo ciático e tratado com injeção local de suspensão de células de Schwann cultivadas ou de extrato de medula espinal lesada: implicações na terapia celular para o reparo do nervo

    OpenAIRE

    João Gabriel Martins Dallo; Bernardo Vergara Reichert; José Benedito Ramos Valladão Júnior; Camila Silva; Bianca Aparecida de Luca; Beatriz de Freitas Azevedo Levy; Gerson Chadi

    2007-01-01

    PURPOSE: Reactive astrocytes are implicated in several mechanisms after central or peripheral nervous system lesion, including neuroprotection, neuronal sprouting, neurotransmission and neuropathic pain. Schwann cells (SC), a peripheral glia, also react after nerve lesion favoring wound/repair, fiber outgrowth and neuronal regeneration. We investigated herein whether cell therapy for repair of lesioned sciatic nerve may change the pattern of astroglial activation in the spinal cord ventral or...

  4. Effects of acute administration of selective serotonin reuptake inhibitors on sympathetic nerve activity

    Energy Technology Data Exchange (ETDEWEB)

    Tiradentes, R.V. [Departamento de Ciências Fisiológicas, Centro de Ciências da Saúde, Universidade Federal do Espírito Santo, Vitória, ES (Brazil); Centro Universitário do Espírito Santo, Colatina, ES (Brazil); Pires, J.G.P. [Centro Universitário do Espírito Santo, Colatina, ES (Brazil); Escola de Medicina da Empresa Brasileira de Ensino, Vitória, ES (Brazil); Silva, N.F. [Departamento de Morfologia, Centro de Ciências da Saúde, Universidade Federal do Espírito Santo, Vitória, ES (Brazil); Ramage, A.G. [Department of Neuroscience, Physiology and Pharmacology, University College London, London (United Kingdom); Santuzzi, C.H. [Departamento de Ciências Fisiológicas, Centro de Ciências da Saúde, Universidade Federal do Espírito Santo, Vitória, ES (Brazil); Centro Universitário do Espírito Santo, Colatina, ES (Brazil); Futuro, H.A. Neto [Escola de Medicina da Empresa Brasileira de Ensino, Vitória, ES (Brazil); Departamento de Morfologia, Centro de Ciências da Saúde, Universidade Federal do Espírito Santo, Vitória, ES (Brazil); Escola Superior de Ciências da Saúde, Santa Casa de Misericórdia de Vitória, Vitória, ES (Brazil)

    2014-05-30

    Serotonergic mechanisms have an important function in the central control of circulation. Here, the acute effects of three selective serotonin (5-HT) reuptake inhibitors (SSRIs) on autonomic and cardiorespiratory variables were measured in rats. Although SSRIs require 2-3 weeks to achieve their full antidepressant effects, it has been shown that they cause an immediate inhibition of 5-HT reuptake. Seventy male Wistar rats were anesthetized with urethane and instrumented to record blood pressure, heart rate, renal sympathetic nerve activity (RSNA), and respiratory frequency. At lower doses, the acute cardiovascular effects of fluoxetine, paroxetine and sertraline administered intravenously were insignificant and variable. At middle and higher doses, a general pattern was observed, with significant reductions in sympathetic nerve activity. At 10 min, fluoxetine (3 and 10 mg/kg) reduced RSNA by -33±4.7 and -31±5.4%, respectively, without changes in blood pressure; 3 and 10 mg/kg paroxetine reduced RSNA by -35±5.4 and -31±5.5%, respectively, with an increase in blood pressure +26.3±2.5; 3 mg/kg sertraline reduced RSNA by -59.4±8.6%, without changes in blood pressure. Sympathoinhibition began 5 min after injection and lasted approximately 30 min. For fluoxetine and sertraline, but not paroxetine, there was a reduction in heart rate that was nearly parallel to the sympathoinhibition. The effect of these drugs on the other variables was insignificant. In conclusion, acute peripheral administration of SSRIs caused early autonomic cardiovascular effects, particularly sympathoinhibition, as measured by RSNA. Although a peripheral action cannot be ruled out, such effects are presumably mostly central.

  5. Effect of an exo-polysaccharide from the culture broth of Hericium erinaceus on enhancement of growth and differentiation of rat adrenal nerve cells

    OpenAIRE

    Park, Young Shik; Lee, Hyun Soo; Won, Moo Ho; Lee, Jin Ha; Lee, Shin Young; Lee, Hyeon Yong

    2002-01-01

    It was found that an exo-biopolymer (M.W. 1,000,000, molar ratio of 1.5:1.7:1.2:0.6:0.9, glucose:galactose:xylose:mannose:fructose, purity 99%) purified from the liquid culture broth of Hericium erinaceus mycelium enhanced the growth of rat adrenal nerve cells. The polymer also improved the extension of the neurites of PC12 cell. Its efficacy was found to be higher than those from known nerve growth factors such as Nerve Growth Factor (NGF) and Brain-Derived Nerve Factor (BDNF). The effect of...

  6. Nerve biopsy

    Science.gov (United States)

    Biopsy - nerve ... A nerve biopsy is most often done on a nerve in the ankle, forearm, or along a rib. The health care ... feel a prick and a mild sting. The biopsy site may be sore for a few days ...

  7. The apolipoprotein A-I gene is actively expressed in the rapidly myelinating avian peripheral nerve

    OpenAIRE

    1989-01-01

    The expression of the apolipoprotein A-I (apo A-I) gene was investigated in the myelinating sciatic nerve. Hybridization analysis with an apo A-I cDNA probe obtained from a cDNA library of mRNA isolated from rapidly myelinating chick sciatic nerve indicated that apo A-I coding transcripts increase during development in the chick sciatic nerve in parallel with the increase of myelin lamellae. Substantial apo A-I-like immunoreactivity in chick sciatic nerve homogenates was detected by Western b...

  8. Expression patterns of cell cycle components in sporadic and neurofibromatosis type 1-related malignant peripheral nerve sheath tumors

    NARCIS (Netherlands)

    Agesen, Trude Holmeide; Florenes, Viva Ann; Molenaar, Willemina M.; Lind, Guro E.; Berner, Jeane-Marie; Plaat, Boudewijn E.C.; Komdeur, Rudy; Myklebost, Ola; van den Berg, Eva; Lothe, Ragnhild A.

    2005-01-01

    The molecular biology underlying the development of highly malignant peripheral nerve sheath tumors (MPNSTs) remains mostly unknown. In the present study, the expression pattern of 10 selected cell cycle components is investigated in a series of 15 MPNSTs from patients with (n = 9) or without (n = 5

  9. Conditional deletion of the Itgb4 integrin gene in Schwann cells leads to delayed peripheral nerve regeneration.

    NARCIS (Netherlands)

    Zee, C.E.E.M. van der; Kreft, M.; Beckers, G.; Kuipers, A.; Sonnenberg, A.

    2008-01-01

    Several different integrins participate in the complex interactions that promote repair of the peripheral nervous system. The role of the integrin alpha6beta4 in peripheral nerve regeneration was investigated in mice by cre-mediated deletion of the Itgb4 (beta4) gene in Schwann cells. After a crush

  10. Positive effects of bFGF modified rat amniotic epithelial cells transplantation on transected rat optic nerve.

    Directory of Open Access Journals (Sweden)

    Jia-Xin Xie

    Full Text Available Effective therapy for visual loss caused by optic nerve injury or diseases has not been achieved even though the optic nerve has the regeneration potential after injury. This study was designed to modify amniotic epithelial cells (AECs with basic fibroblast growth factor (bFGF gene, preliminarily investigating its effect on transected optic nerve.A human bFGF gene segment was delivered into rat AECs (AECs/hbFGF by lentiviral vector, and the gene expression was examined by RT-PCR and ELISA. The AECs/hbFGF and untransfected rat AECs were transplanted into the transected site of the rat optic nerve. At 28 days post transplantation, the survival and migration of the transplanted cells was observed by tracking labeled cells; meanwhile retinal ganglion cells (RGCs were observed and counted by employing biotin dextran amine (BDA and Nissl staining. Furthermore, the expression of growth associated protein 43 (GAP-43 within the injury site was examined with immunohistochemical staining.The AECs/hbFGF was proven to express bFGF gene and secrete bFGF peptide. Both AECs/hbFGF and AECs could survive and migrate after transplantation. RGCs counting implicated that RGCs numbers of the cell transplantation groups were significantly higher than that of the control group, and the AECs/hbFGF group was significantly higher than that of the AECs group. Moreover GAP-43 integral optical density value in the control group was significantly lower than that of the cell transplantation groups, and the value in the AECs/hbFGF group was significantly higher than that of the AECs group.AECs modified with bFGF could reduce RGCs loss and promote expression of GAP-43 in the rat optic nerve transected model, facilitating the process of neural restoration following injury.

  11. Activation of NTS A2a adenosine receptors differentially resets baroreflex control of renal vs. adrenal sympathetic nerve activity.

    Science.gov (United States)

    Ichinose, Tomoko K; O'Leary, Donal S; Scislo, Tadeusz J

    2009-04-01

    The role of nucleus of solitary tract (NTS) A(2a) adenosine receptors in baroreflex mechanisms is controversial. Stimulation of these receptors releases glutamate within the NTS and elicits baroreflex-like decreases in mean arterial pressure (MAP), heart rate (HR), and renal sympathetic nerve activity (RSNA), whereas inhibition of these receptors attenuates HR baroreflex responses. In contrast, stimulation of NTS A(2a) adenosine receptors increases preganglionic adrenal sympathetic nerve activity (pre-ASNA), and the depressor and sympathoinhibitory responses are not markedly affected by sinoaortic denervation and blockade of NTS glutamatergic transmission. To elucidate the role of NTS A(2a) adenosine receptors in baroreflex function, we compared full baroreflex stimulus-response curves for HR, RSNA, and pre-ASNA (intravenous nitroprusside/phenylephrine) before and after bilateral NTS microinjections of selective adenosine A(2a) receptor agonist (CGS-21680; 2.0, 20 pmol/50 nl), selective A(2a) receptor antagonist (ZM-241385; 40 pmol/100 nl), and nonselective A(1) + A(2a) receptor antagonist (8-SPT; 1 nmol/100 nl) in urethane/alpha-chloralose anesthetized rats. Activation of A(2a) receptors decreased the range, upper plateau, and gain of baroreflex-response curves for RSNA, whereas these parameters all increased for pre-ASNA, consistent with direct effects of the agonist on regional sympathetic activity. However, no resetting of baroreflex-response curves along the MAP axis occurred despite the marked decreases in baseline MAP. The antagonists had no marked effects on baseline variables or baroreflex-response functions. We conclude that the activation of NTS A(2a) adenosine receptors differentially alters baroreflex control of HR, RSNA, and pre-ASNA mostly via non-baroreflex mechanism(s), and these receptors have virtually no tonic action on baroreflex control of these sympathetic outputs.

  12. Sacral nerve stimulation increases activation of the primary somatosensory cortex by anal canal stimulation in an experimental model.

    LENUS (Irish Health Repository)

    Griffin, K M

    2011-08-01

    Sacral and posterior tibial nerve stimulation may be used to treat faecal incontinence; however, the mechanism of action is unknown. The aim of this study was to establish whether sensory activation of the cerebral cortex by anal canal stimulation was increased by peripheral neuromodulation.

  13. Muscle pain perception and sympathetic nerve activity to exercise during opioid modulation

    Science.gov (United States)

    Cook, D. B.; O'Connor, P. J.; Ray, C. A.

    2000-01-01

    The purpose of this experiment was to examine the effects of the endogenous opioid system on forearm muscle pain and muscle sympathetic nerve activity (MSNA) during dynamic fatiguing exercise. Twelve college-age men (24 +/- 4 yr) performed graded (1-min stages; 30 contractions/min) handgrip to fatigue 1 h after the ingestion of either 60 mg codeine, 50 mg naltrexone, or placebo. Pain (0-10 scale) and exertion (0-10 and 6-20 scales) intensities were measured during the last 15 s of each minute of exercise and every 15 s during recovery. MSNA was measured continuously from the peroneal nerve in the left leg. Pain threshold occurred earlier [1.8 +/- 1, 2. 2 +/- 1, 2.2 +/- 1 J: codeine, naltrexone, and placebo, respectively] and was associated with a lower rating of perceived exertion (RPE) (2.7 +/- 2, 3.6 +/- 2, 3.8 +/- 2: codeine, naltrexone, and placebo, respectively) in the codeine condition compared with either the naltrexone or placebo conditions. There were no main effects (i.e., drugs) or interaction (i.e., drugs x time) for either forearm muscle pain or RPE during exercise [pain: F (2, 22) = 0.69, P = 0.51]. There was no effect of drug on MSNA, heart rate, or blood pressure during baseline, exercise, or recovery. Peak exercise MSNA responses were 21 +/- 1, 21 +/- 2.0, and 21 +/- 2.0 bursts/30 s for codeine, naltrexone, and placebo conditions, respectively. Peak mean arterial pressure responses were 135 +/- 4, 131 +/- 3, and 132 +/- 4 mmHg for codeine, naltrexone, and placebo conditions, respectively. It is concluded that neither 60 mg codeine nor 50 mg naltrexone has an effect on forearm muscle pain, exertion, or MSNA during high- intensity handgrip to fatigue.

  14. Uterine autonomic nerve innervation plays a crucial role in regulating rat uterine mast cell functions during embryo implantation.

    Science.gov (United States)

    Yuan, Xue-Jun; Huang, Li-Bo; Qiao, Hui-Li; Deng, Ze-Pei; Fa, Jing-Jing

    2009-12-01

    To explore the potential mechanism of how uterine innervations would affect the uterine mast cell (MC) population and functions during the periimplantation. We herein first examined the consequence of uterine neurectomy on embryo implantation events. We observed that amputation of autonomic nerves innervating the uterus led to on-time implantation failure in rats. Exploiting MC culture and ELISA approaches, we then further analyzed the effect of neurectomy on cellular histamine levels and its release from uterine MCs, to elucidate the relation of the autonomic nerves and local cellular immunity in the uterine during early pregnancy. We observed that disconnection of autonomic nerve innervation significantly increased the population of uterine MCs. Most interestingly, these increased number of uterine MCs in neuroectomized rats contained a much reduced cellular level of histamine. Our subsequent challenge experiments revealed that uterine MCs in nerve amputated rats exhibited enhanced histamine releasing rate in response to substance P and antiIgE, suggesting loss of nerve innervation in the uterus not only increases the population of uterine MCs, but also facilitates the release of histamine from MCs, thus subsequently interfere with the normal implantation process. Collectively, our findings provide a new line of evidence supporting the concept that immune-neuro-endocrine network plays important role during pregnancy establishment and maintenance. PMID:19765668

  15. Mitochondrial energy metabolism changes during aging-mouse cranial nerve cells treated with various doses and forms of Fructus schizandrae

    Institute of Scientific and Technical Information of China (English)

    Hongyan Guo; Jinhe Li

    2008-01-01

    BACKGROUND: During the cellular aging process, the number of mitochondria, generation of adenosine triphosphate (ATP), activity of respiratory chain enzyme complex 1 and 4, and oxidation decrease. OBJECTIVE: To observe the effects of aqueous and spirituous extract, as well as polysaccharides from Fructus schizandrae (Magnolia Vine) on energy metabolism and mitochondrial anti-oxidation in cranial nerve cells of a D-gal-induccd aging mouse model.DESIGN, TIME AND SETTING: A randomized, controlled, animal study. The experiment was conducted at the Department of Biochemistry, Qiqihar Medical College between March and July 2006.MATERIALS: Fifty healthy, Kunming mice of both sexes, aged 2 3 months old and weighing 18-22 g, were used for the present study. Fructus schizandrae was purchased from the Medical College of Jiamusi University. Aqueous extracts, spirituous extracts, and polysaccharides from Fructus schizandrae were prepared. D-galactose (D-gal) is a product of the Second Reagent Factory, Shanghai City, China. Mn-superoxide dismutase (Mn-SOD) kit, malonaldehyde (MDA) kit, protein quantification kit, and inorganic phosphorus testing kit were purchased from Jian Cheng Bioeng. Co., China.METHODS: Fifty mice were randomly divided into five groups, with 10 mice in each group: young control, aging model, aqueous Fructus schizandrae extract, spirituous Fructus schizandrae extract, and Fructus schizandrae polysaccharides. Over a course of 30 days, mice in aging model, aqueous Fructus schizandrae extract, spirituous Fructus schizandrae extract, and Fructus schizandrae polysaccharides groups were injected subcutaneously with D-gal (100 mg/kg) into the nape of the neck daily, and administered intragastrically with an equal volume of sterile, warm water (aging model), aqueous Fructus schizandrae extract (2 g/kg), spirituous Fructus schizandrae extract (2 g/kg), or Fructus schizandrae polysaccharides (0.2 g/kg), respectively. Mice in the young control group were injected into

  16. Ratios between number of neuroglial cells and number and volume of nerve cells in the spinal ganglia of two species of reptiles and three species of mammals.

    Science.gov (United States)

    Ledda, M; De Palo, S; Pannese, E

    2004-02-01

    We studied the ratios between number of neuroglial (=satellite) cells and number and volume of neurons with which they are associated in the spinal ganglia of two species of reptiles (lizard and gecko) and three species of mammals (mouse, rat, and rabbit). In all five species, we found that the number of satellite cells associated with a nerve cell body increased with increasing volume of the latter. This result shows that there is a quantitative balance between neuroglia and nerve tissue in spinal ganglia. This balance seems to be maintained by a tight regulation of the number of satellite cells. We also found that the mean volume of nerve cell body corresponding to a satellite cell was lower for small neurons than for large ones. Since satellite cells metabolically support spinal ganglion neurons, the metabolic needs of small neurons are better satisfied than those of large ones. For a nerve cell body of a given size, the number of associated satellite cells did not differ between the lizard and gecko, nor between the mouse, rat, and rabbit. However, this number was significantly smaller in the reptiles than in the mammals. This result could be explained by the lower metabolic rate in the nervous system of poikilotherms than mammals, or could have a phylogenetic significance. These two interpretations are not mutually exclusive. PMID:14729453

  17. Stem Cell Ophthalmology Treatment Study (SCOTS for retinal and optic nerve diseases: a preliminary report

    Directory of Open Access Journals (Sweden)

    Jeffrey N Weiss

    2015-01-01

    Full Text Available In this report, we present the results of a single patient with optic neuropathy treated within the Stem Cell Ophthalmology Treatment Study (SCOTS. SCOTS is an Institutional Review Board approved clinical trial and is the largest ophthalmology stem cell study registered at the National Institutes of Health to date- www.clinicaltrials.gov Identifier NCT 01920867. SCOTS utilizes autologous bone marrow-derived stem cells in the treatment of optic nerve and retinal diseases. Pre- and post-treatment comprehensive eye exams were independently performed at the Wilmer Eye Institute at the Johns Hopkins Hospital, USA. A 27 year old female patient had lost vision approximately 5 years prior to enrollment in SCOTS. Pre-treatment best-corrected visual acuity at the Wilmer Eye Institute was 20/800 Right Eye (OD and 20/4,000 Left Eye (OS. Four months following treatment in SCOTS, the central visual acuity had improved to 20/100 OD and 20/40 OS.

  18. Effect of a Nerve Graft Substitute Single-walled Carbon Nanotubes on Rat Pheochromocytoma Cells

    Institute of Scientific and Technical Information of China (English)

    WU Qian; ZHANG Juan; HU Zheqin

    2015-01-01

    Carbon nanotubes (CNTs) were extensively explored for their beneficial use in nervous system tissue engineering. However, an important concern regarding the use of CNTs is their toxicity during the interaction between cells and the nano particles. The rat pheochromocytoma cell line (PC12) was co-cultured with three types of single-walled carbon nanotubes (SWNTs), purified raw SWNTs (C), hydroxyl purified SWNTs (C-OH) and carboxyl purified SWNTs (C-COOH) at 25 µg/mL and 100 µg/ml. The experimental results revealed that SWNTs at the concentration below 100 µg/mL did not affect the cell viability. Notably, powerful antioxidant system in nerous system tissue is able to counteract with the toxicity of CNTs, which is characterized by the prominently enhanced expression of main antioxidant enzymes (catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione-S-transferase (GST)). Therefore, we believe that CNTs can be good candidates for the fabrication of biomedical scaffolds for the nerve tissue repair.

  19. Light microscopic image analysis system to quantify immunoreactive terminal area apposed to nerve cells

    Science.gov (United States)

    Wu, L. C.; D'Amelio, F.; Fox, R. A.; Polyakov, I.; Daunton, N. G.

    1997-01-01

    The present report describes a desktop computer-based method for the quantitative assessment of the area occupied by immunoreactive terminals in close apposition to nerve cells in relation to the perimeter of the cell soma. This method is based on Fast Fourier Transform (FFT) routines incorporated in NIH-Image public domain software. Pyramidal cells of layer V of the somatosensory cortex outlined by GABA immunolabeled terminals were chosen for our analysis. A Leitz Diaplan light microscope was employed for the visualization of the sections. A Sierra Scientific Model 4030 CCD camera was used to capture the images into a Macintosh Centris 650 computer. After preprocessing, filtering was performed on the power spectrum in the frequency domain produced by the FFT operation. An inverse FFT with filter procedure was employed to restore the images to the spatial domain. Pasting of the original image to the transformed one using a Boolean logic operation called 'AND'ing produced an image with the terminals enhanced. This procedure allowed the creation of a binary image using a well-defined threshold of 128. Thus, the terminal area appears in black against a white background. This methodology provides an objective means of measurement of area by counting the total number of pixels occupied by immunoreactive terminals in light microscopic sections in which the difficulties of labeling intensity, size, shape and numerical density of terminals are avoided.

  20. Stem Cell Ophthalmology Treatment Study (SCOTS) for retinal and optic nerve diseases:a preliminary report

    Institute of Scientific and Technical Information of China (English)

    Jeffrey N Weiss; Steven Levy; Alexis Malkin

    2015-01-01

    In this report, we present the results of a single patient with optic neuropathy treated within the Stem Cell Ophthalmology Treatment Study (SCOTS). SCOTS is an Institutional Review Board approved clinical trial and is the largest ophthalmology stem cell study registered at the National Institutes of Health to date-www.clinicaltrials.gov Identifier NCT 01920867. SCOTS utilizes autologous bone marrow-derived stem cells in the treatment of optic nerve and retinal diseases. Pre-and post-treatment comprehensive eye exams were independently performed at the Wilmer Eye Institute at the Johns Hopkins Hospital, USA. A 27 year old female patient had lost vision approximately 5 years prior to enrollment in SCOTS. Pre-treatment best-corrected visual acuity at the Wilmer Eye Institute was 20/800 Right Eye (OD) and 20/4,000 Left Eye (OS). Four months following treatment in SCOTS, the central visual acuity had improved to 20/100 OD and 20/40 OS.

  1. Engraftment and Differentiation of Embryonic Stem Cell–Derived Neural Progenitor Cells in the Cochlear Nerve Trunk: Growth of Processes into the Organ of Corti

    OpenAIRE

    Corrales, C. Eduardo; Pan, Luying; Li, Huawei; Liberman, M. Charles; Heller, Stefan; Edge, Albert S. B.

    2006-01-01

    Hearing loss in mammals is irreversible because cochlear neurons and hair cells do not regenerate. To determine whether we could replace neurons lost to primary neuronal degeneration, we injected EYFP-expressing embryonic stem cell–derived mouse neural progenitor cells into the cochlear nerve trunk in immunosuppressed animals 1 week after destroying the cochlear nerve (spiral ganglion) cells while leaving hair cells intact by ouabain application to the round window at the base of the cochlea ...

  2. Neuritin 1 promotes retinal ganglion cell survival and axonal regeneration following optic nerve crush.

    Science.gov (United States)

    Sharma, T P; Liu, Y; Wordinger, R J; Pang, I-H; Clark, A F

    2015-01-01

    Neuritin 1 (Nrn1) is an extracellular glycophosphatidylinositol-linked protein that stimulates axonal plasticity, dendritic arborization and synapse maturation in the central nervous system (CNS). The purpose of this study was to evaluate the neuroprotective and axogenic properties of Nrn1 on axotomized retinal ganglion cells (RGCs) in vitro and on the in vivo optic nerve crush (ONC) mouse model. Axotomized cultured RGCs treated with recombinant hNRN1 significantly increased survival of RGCs by 21% (n=6-7, P<0.01) and neurite outgrowth in RGCs by 141% compared to controls (n=15, P<0.05). RGC transduction with AAV2-CAG-hNRN1 prior to ONC promoted RGC survival (450%, n=3-7, P<0.05) and significantly preserved RGC function by 70% until 28 days post crush (dpc) (n=6, P<0.05) compared with the control AAV2-CAG-green fluorescent protein transduction group. Significantly elevated levels of RGC marker, RNA binding protein with multiple splicing (Rbpms; 73%, n=5-8, P<0.001) and growth cone marker, growth-associated protein 43 (Gap43; 36%, n=3, P<0.01) were observed 28 dpc in the retinas of the treatment group compared with the control group. Significant increase in Gap43 (100%, n=5-6, P<0.05) expression was observed within the optic nerves of the AAV2-hNRN1 group compared to controls. In conclusion, Nrn1 exhibited neuroprotective, regenerative effects and preserved RGC function on axotomized RGCs in vitro and after axonal injury in vivo. Nrn1 is a potential therapeutic target for CNS neurodegenerative diseases. PMID:25719245

  3. Active skin perfusion and thermoregulatory response in the hand following nerve injury and repair in human upper extremities.

    Science.gov (United States)

    Deng, Aidong; Liu, Dan; Gu, Chen; Gu, Xiaosong; Gu, Jianhui; Hu, Wen

    2016-01-01

    Cutaneous vasoconstriction/vasodilatation occurs in response to whole body and local cooling/heating, and the vasomotor activities play a pivotal role in thermal control of the human body. The mechanisms underlying regulation of skin blood flow involve both neurogenic and humeral/local chemical influence, contributing to the initial response to thermal stimuli and the prolonged phase of response, respectively. Previous studies have suggested the impairment of cutaneous thermal regulation after nerve injury. However, the evidence regarding how the skin perfusion and thermoregulatory response evolve after nerve injury and repair remains limited. Here we observed, by utilizing laser-Doppler perfusion imaging, baseline skin perfusion and perfusion change in response to thermal stimuli after median and ulnar nerve injury, and the results showed that baseline perfusion in autonomous skin area profoundly decreased and active rewarming after clod stress dramatically diminished before sensory recovery of the skin became detectable. In addition, baseline cutaneous perfusion was recovered as the skin regained touch sensation, and exhibited positive correlation to touch sensibility of the skin. These data indicate that both active perfusion and thermoregulatory response of the skin are markedly compromised during skin denervation and can be recovered by re-innervation. This suggests the importance of timely repair of injured nerve, especially in the practice of replantation.

  4. Regulation of Nerve Growth Factor Release by Nitric Oxide through Cyclic GMP Pathway in Cortical Glial Cells

    OpenAIRE

    Xiong, Huabao; YAMADA, Kiyofumi; Jourdi, Hussam; KAWAMURA, MEIKO; TAKEI, NOBUYUKI; HAN, DAIKEN; Nabeshima, Toshitaka; Nawa, Hiroyuki

    1999-01-01

    In the present study, we found that S-nitroso-N-acetyl-dl-penicillamine, a spontaneous nitric oxide (NO) generator, dose-dependently inhibited basal nerve growth factor (NGF) release from mixed glial cells. To elucidate the function of endogenous NO in the regulation of NGF release, the mixed glial cells were stimulated with lipopolysaccharide (LPS) or LPS plus interfer-on-γ (IFNγ). The results showed that LPS alone induced NGF release and moderate NO production. However, costimulation with L...

  5. Altered nerve growth factor in fibroblasts from patients with familial dysautonomia.

    OpenAIRE

    Schwartz, J P; Breakefield, X O

    1980-01-01

    Nerve growth factor was measured in cultured human skin fibroblasts from controls and from patients with familial dysautonomia and dystonia musculoram deformans. Cells from these sources grown over a range of cell densities contained similar levels of beta-nerve growth factor as measured by radioimmunoassay. Results of bioassay demonstrated that the nerve growth factor from dysautonomic cells was only approximately 10% as active per ng of immunoreactive protein as that from control and dyston...

  6. Hypothalamic Nesfatin-1 Stimulates Sympathetic Nerve Activity via Hypothalamic ERK Signaling.

    Science.gov (United States)

    Tanida, Mamoru; Gotoh, Hitoshi; Yamamoto, Naoki; Wang, Mofei; Kuda, Yuhichi; Kurata, Yasutaka; Mori, Masatomo; Shibamoto, Toshishige

    2015-11-01

    Nesfatin-1 acts on the hypothalamus and regulates the autonomic nervous system. However, the hypothalamic mechanisms of nesfatin-1 on the autonomic nervous system are not well understood. In this study, we found that intracerebroventricular (ICV) administration of nesfatin-1 increased the extracellular signal-regulated kinase (ERK) activity in rats. Furthermore, the activity of sympathetic nerves, in the kidneys, liver, and white adipose tissue (WAT), and blood pressure was stimulated by the ICV injection of nesfatin-1, and these effects were abolished owing to pharmacological inhibition of ERK. Renal sympathoexcitatory and hypertensive effects were also observed with nesfatin-1 microinjection into the paraventricular hypothalamic nucleus (PVN). Moreover, nesfatin-1 increased the number of phospho (p)-ERK1/2-positive neurons in the PVN and coexpression of the protein in neurons expressing corticotropin-releasing hormone (CRH). Pharmacological blockade of CRH signaling inhibited renal sympathetic and hypertensive responses to nesfatin-1. Finally, sympathetic stimulation of WAT and increased p-ERK1/2 levels in response to nesfatin-1 were preserved in obese animals such as rats that were fed a high-fat diet and leptin receptor-deficient Zucker fatty rats. These findings indicate that nesfatin-1 regulates the autonomic nervous system through ERK signaling in PVN-CRH neurons to maintain cardiovascular function and that the antiobesity effect of nesfatin-1 is mediated by hypothalamic ERK-dependent sympathoexcitation in obese animals. PMID:26310564

  7. Reflex control of rat tail sympathetic nerve activity by abdominal temperature

    Science.gov (United States)

    Shafton, Anthony D; Kitchener, Peter; McKinley, Michael J; McAllen, Robin M

    2014-01-01

    The thermoregulatory reflex effects of warming and cooling in the abdomen were investigated in 4 urethane-anesthetized Sprague-Dawley rats. Animals were shaved and surrounded by a water-perfused silastic jacket. Skin temperature under the jacket was recorded by thermocouples at 3 sites and brain temperature was monitored by a thermocouple inserted lateral to the hypothalamus. A heat exchanger made from an array of silicon tubes in parallel loops was placed through a ventral incision into the abdomen; it rested against the intestinal serosa and the temperature of this interface was monitored by a thermocouple. Few- or multi-unit postganglionic activity was recorded from sympathetic nerves supplying tail vessels (tail SNA). Intra-abdominal temperature was briefly lowered or raised between 35–41 °C by perfusing the heat exchanger with cold or warm water. Warming the abdomen inhibited tail SNA while cooling it excited tail SNA in all 4 animals. We also confirmed that cooling the trunk skin activated tail SNA. Multivariate analysis of tail SNA with respect to abdominal, brain and trunk skin temperatures revealed that all had highly significant independent inhibitory actions on tail SNA, but in these experiments abdominal temperature had the weakest and brain temperature the strongest effect. We conclude that abdominal temperature has a significant thermoregulatory action in the rat, but its influence on cutaneous vasomotor control appears to be weaker than that of skin or brain temperatures.

  8. Biocompatibility evaluation of electrospun aligned poly(propylene carbonate) nanofibrous scaffolds with peripheral nerve tissues and cells in vitro

    Institute of Scientific and Technical Information of China (English)

    WANG Yu; ZHAO Zhe; ZHAO Bin; QI Hong-xu; PENG Jiang; ZHANG Li; XU Wen-jing; HU Ping; LU Shi-bi

    2011-01-01

    Background Peripheral nerve regeneration across large gaps is clinically challenging. Scaffold design plays a pivotal role in nerve tissue engineering. Recently, nanofibrous scaffolds have proven a suitable environment for cell attachment and proliferation due to similarities of their physical properties to natural extracellular matrix. Poly(propylene carbonate)(PPC) nanofibrous scaffolds have been investigated for vascular tissue engineering. However, no reports exist of PPC nanofibrous scaffolds for nerve tissue engineering. This study aimed to evaluate the potential role of aligned and random PPC nanofibrous scaffolds as substrates for peripheral nerve tissue and cells in nerve tissue engineering. Methods Aligned and random PPC nanofibrous scaffolds were fabricated by electrospinning and their chemical characterization were carried out using scanning electron microscopy (SEM). Dorsal root ganglia (DRG) from Sprague-Dawley rats were cultured on the nanofibrous substrates for 7 days. Neurite outgrowth and Schwann-cell migration from DRG were observed and quantified using immunocytochemistry and SEM. Schwann cells derived from rat sciatic nerves were cultured in electrospun PPC scaffold-extract fluid for 24, 48, 72 hours and 7 days. The viability of Schwann cells was evaluated by 3-[4,5-dimethyl(thiazol-2-yl)-2,5-diphenyl] tetrazolium bromide (MTT) assay. Results The diameter of aligned and random fibers ranged between 800 nm and 1200 nm, and the thickness of the films was approximately 10-20 μm. Quantification of aligned fiber films revealed approximately 90% alignment of all fibers along the longitudinal axis. However, with random fiber films, the alignment of fibers was random through all angle bins. Rat DRG explants were grown on PPC nanofiber films for up to 1 week. On the aligned fiber films, the majority of neurite outgrowth and Schwann cell migration from the DRG extended unidirectionally, parallel to the aligned fibers.However, on the random fiber films

  9. Direct conscious telemetry recordings demonstrate increased renal sympathetic nerve activity in rats with chronic kidney disease

    Directory of Open Access Journals (Sweden)

    Ibrahim M Salman

    2015-08-01

    Full Text Available Chronic kidney disease (CKD is associated with sympathetic hyperactivity and impaired blood pressure control reflex responses, yet direct evidence demonstrating these features of autonomic dysfunction in conscious animals is still lacking. Here we measured renal sympathetic nerve activity (RSNA and mean arterial pressure (MAP using telemetry-based recordings in a rat model of CKD, the Lewis Polycystic Kidney (LPK rat, and assessed responses to chemoreflex activation and acute stress. Male LPK and Lewis control animals (total n=16 were instrumented for telemetric recording of RSNA and MAP. At 12–13 weeks-of-age, resting RSNA and MAP, sympathetic and haemodynamic responses to both peripheral (hypoxia: 10% O2 and central chemoreflex (hypercapnia: 7% CO2 activation and acute stress (open-field exposure, were measured. As indicators of renal function, urinary protein (UPro and creatinine (Ucr levels were assessed. LPK rats had higher resting RSNA (1.2±0.1 vs. 0.6±0.1 µV, p<0.05 and MAP (151±8 vs. 97±2 mmHg, p<0.05 compared to Lewis. MAP was negatively correlated with Ucr (r=-0.80, p=0.002 and positively correlated with RSNA (r=0.66, p=0.014, with multiple linear regression modeling indicating the strongest correlation was with Ucr. RSNA and MAP responses to activation of the central chemoreflex and open-field stress were reduced in the LPK relative to the Lewis (all p<0.05. This is the first description of dual conscious telemetry recording of RSNA and MAP in a genetic rodent model of CKD. Elevated RSNA is likely a key contributor to the marked hypertension in this model, while attenuated RSNA and MAP responses to central chemoreflex activation and acute stress in the LPK indicate possible deficits in the neural processing of autonomic outflows evoked by these sympathoexcitatory pathways.

  10. Perinatal taurine exposure programs patterns of autonomic nerve activity responses to tooth pulp stimulation in adult male rats

    Science.gov (United States)

    Khimsuksri, Sawita; Wyss, J. Michael; Thaeomor, Atcharaporn; Paphangkorakit, Jarin; Jirakulsomchok, Dusit; Roysommuti, Sanya

    2016-01-01

    Perinatal taurine excess or deficit influences adult health and disease, especially relative to the autonomic nervous system. This study tests the hypothesis that perinatal taurine exposure influences adult autonomic nervous system control of arterial pressure in response to acute electrical tooth pulp stimulation. Female Sprague-Dawley rats were fed normal rat chow with 3% β-alanine (taurine depletion, TD), 3% taurine (taurine supplementation, TS) or water alone (control, C) from conception to weaning. Their male offspring were fed normal rat chow and tap water throughout the experiment. At 8–10 weeks of age, blood chemistry, arterial pressure, heart rate and renal sympathetic nerve activity were measured in anesthetized rats. Age, body weight, mean arterial pressure, heart rate, plasma electrolytes, blood urea nitrogen, plasma creatinine and plasma cortisol were not significantly different among the three groups. Before tooth pulp stimulation, low (0.3–0.5 Hz) and high frequency (0.5–4.0 Hz) power spectral densities of arterial pressure were not significantly different among groups, while the power spectral densities of renal sympathetic nerve activity were significantly decreased in TD compared to control rats. Tooth pulp stimulation did not change arterial pressure, heart rate, renal sympathetic nerve and arterial pressure power spectral densities in the 0.3–4.0 Hz spectrum or renal sympathetic nerve firing rate in any group. In contrast, perinatal taurine imbalance disturbed very low frequency power spectral densities of both arterial pressure and renal sympathetic nerve activity (below 0.1 Hz), both before and after the tooth pulp stimulation. The power densities of TS were most sensitive to ganglionic blockade and central adrenergic inhibition, while those of TD were sensitive to both central and peripheral adrenergic inhibition. The present data indicate that perinatal taurine imbalance can lead to aberrant autonomic nervous system responses in

  11. Dorsal root ganglion-derived Schwann cells combined with poly(lactic-co-glycolic acid)/chitosan conduits for the repair of sciatic nerve defects in rats

    OpenAIRE

    Zhao, Li; Qu, Wei; Wu, Yuxuan; Ma, Hao; Jiang, Huajun

    2014-01-01

    Schwann cells, nerve regeneration promoters in peripheral nerve tissue engineering, can be used to repair both the peripheral and central nervous systems. However, isolation and purification of Schwann cells are complicated by contamination with fibroblasts. Current reported measures are mainly limited by either high cost or complicated procedures with low cell yields or purity. In this study, we collected dorsal root ganglia from neonatal rats from which we obtained highly purified Schwann c...

  12. Effect of gabapentin on activation of glial cells in spinal cord after chronic constrictive injury to sciatic nerve in rats%加巴喷丁对神经病理性痛大鼠脊髓胶质细胞活化的影响

    Institute of Scientific and Technical Information of China (English)

    林福清; 杨小虎; 侯冷晨; 傅舒昆

    2010-01-01

    Objective To investigate the effect of gabapentin on the activation of glial cells in the spinal cord after chronic constrictive injury (CCI) to sciatic nerve in rats.Methods Twenty-four male SD rats weighing 180-220 g were randomly divided into 3 groups (n = 8 each): group Ⅰ sham operation (group S), group Ⅱ CCI and group Ⅲ gabapentin + CCI. Right sciatic nerve was exposed and 4 loose ligatures were placed with 6-0chromic catgut. Seven days after operation gabapentin 50 mg/kg in 5 ml was given by intragastric gavage twice a day for 5 days in group Ⅲ. Paw withdrawal threshold to mechanical stimulation with von Frey filaments was measured one day before (baseline) and at 7, 15 d after operation. The animals were killed at 15 d after operation. The lumbar segment L4-5 of the spinal cord was removed. Immunohistochemical double mark technique was used to detect the activation of astrocytes and microglias in the spinal cord. Results Paw withdrawal threshold to mechanical stimulation was significantly decreased on the 7th and 15th day after CCI operation in group CCI as compared with group S. After 5 day treatment with gabapentin, the withdrawal threshold to von Frey hair stimulation was significantly higher in group Ⅲ than in group Ⅱ . The activation of astrocytes and microglias in the spinal cord was significantly enhanced in group CCI as compared with group S. Treatment with gabapentin significantly inhibited CCI-induced activation of astrocytes and microglias in the spinal cord. ConclusionGabapentin reduces neuropathic pain by inhibiting activation of glial cells in the spinal cord.%目的 评价加巴喷丁对神经病理性痛大鼠脊髓胶质细胞活化的影响.方法 雄性SD大鼠24只,体重180~220 g,随机分为3组(n=8):假手术组(S组)、坐骨神经慢性压迫性损伤组(CCI组)和加巴喷丁组(G组).CCI组和G组采用坐骨神经慢性压迫性损伤法建立大鼠神经病理性痛模型;S组只暴露坐

  13. Skin sympathetic nerve activity in humans during exposure to emotionally-charged images: sex differences

    Directory of Open Access Journals (Sweden)

    Rachael eBrown

    2014-03-01

    Full Text Available While it is known that anxiety or emotional arousal affects skin sympathetic nerve activity (SSNA, the galvanic skin response (GSR is the most widely used parameter to infer increases in SSNA during stress or emotional studies. We recently showed that SSNA provides a more sensitive measure of emotional state than effector-organ responses. The aim of the present study was to assess whether there are gender differences in the responses of SSNA and other physiological parameters such as blood pressure, heart rate, skin blood flow and sweat release, while subjects viewed neutral or emotionally-charged images from the International Affective Picture System. Changes in SSNA were assessed using microneurography in twenty subjects (ten male and ten female. Blocks of positively-charged (erotica or negatively-charge images (mutilation were presented in a quasi-random fashion, following a block of neutral images, with each block containing fifteen images and lasting two minutes. Images of both erotica and mutilation caused significant increases in SSNA, with increases being greater for males viewing erotica and greater for females viewing mutilation. The increases in SSNA were often coupled with sweat release and cutaneous vasoconstriction; however, these markers were not significantly different than those produced by viewing neutral images and were not always consistent with the SSNA increases. We conclude that SSNA increases with both positively-charged and negatively-charged emotional images, yet sex differences are present.

  14. Skin sympathetic nerve activity in humans during exposure to emotionally-charged images: sex differences.

    Science.gov (United States)

    Brown, Rachael; Macefield, Vaughan G

    2014-01-01

    While it is known that anxiety or emotional arousal affects skin sympathetic nerve activity (SSNA), the galvanic skin response (GSR) is the most widely used parameter to infer increases in SSNA during stress or emotional studies. We recently showed that SSNA provides a more sensitive measure of emotional state than effector-organ responses. The aim of the present study was to assess whether there are gender differences in the responses of SSNA and other physiological parameters such as blood pressure, heart rate, skin blood flow and sweat release, while subjects viewed neutral or emotionally-charged images from the International Affective Picture System (IAPS). Changes in SSNA were assessed using microneurography in 20 subjects (10 male and 10 female). Blocks of positively-charged (erotica) or negatively-charge images (mutilation) were presented in a quasi-random fashion, following a block of neutral images, with each block containing 15 images and lasting 2 min. Images of both erotica and mutilation caused significant increases in SSNA, with increases being greater for males viewing erotica and greater for females viewing mutilation. The increases in SSNA were often coupled with sweat release and cutaneous vasoconstriction; however, these markers were not significantly different than those produced by viewing neutral images and were not always consistent with the SSNA increases. We conclude that SSNA increases with both positively-charged and negatively-charged emotional images, yet sex differences are present. PMID:24678303

  15. Neuropeptide Y acts in the paraventricular nucleus to suppress sympathetic nerve activity and its baroreflex regulation.

    Science.gov (United States)

    Cassaglia, Priscila A; Shi, Zhigang; Li, Baoxin; Reis, Wagner L; Clute-Reinig, Nicholas M; Stern, Javier E; Brooks, Virginia L

    2014-04-01

    Neuropeptide Y (NPY), a brain neuromodulator that has been strongly implicated in the regulation of energy balance, also acts centrally to inhibit sympathetic nerve activity (SNA); however, the site and mechanism of action are unknown. In chloralose-anaesthetized female rats, nanoinjection of NPY into the paraventricular nucleus of the hypothalamus (PVN) dose-dependently suppressed lumbar SNA (LSNA) and its baroreflex regulation, and these effects were blocked by prior inhibition of NPY Y1 or Y5 receptors. Moreover, PVN injection of Y1 and Y5 receptor antagonists in otherwise untreated rats increased basal and baroreflex control of LSNA, indicating that endogenous NPY tonically inhibits PVN presympathetic neurons. The sympathoexcitation following blockade of PVN NPY inhibition was eliminated by prior PVN nanoinjection of the melanocortin 3/4 receptor inhibitor SHU9119. Moreover, presympathetic neurons, identified immunohistochemically using cholera toxin b neuronal tract tracing from the rostral ventrolateral medulla (RVLM), express NPY Y1 receptor immunoreactivity, and patch-clamp recordings revealed that both NPY and α-melanocyte-stimulating hormone (α-MSH) inhibit and stimulate, respectively, PVN-RVLM neurons. Collectively, these data suggest that PVN NPY inputs converge with α-MSH to influence presympathetic neurons. Together these results identify endogenous NPY as a novel and potent inhibitory neuromodulator within the PVN that may contribute to changes in SNA that occur in states associated with altered energy balance, such as obesity and pregnancy. PMID:24535439

  16. Caspase-3 dependent nitrergic neuronal apoptosis following cavernous nerve injury is mediated via RhoA and ROCK activation in major pelvic ganglion.

    Science.gov (United States)

    Hannan, Johanna L; Matsui, Hotaka; Sopko, Nikolai A; Liu, Xiaopu; Weyne, Emmanuel; Albersen, Maarten; Watson, Joseph W; Hoke, Ahmet; Burnett, Arthur L; Bivalacqua, Trinity J

    2016-01-01

    Axonal injury due to prostatectomy leads to Wallerian degeneration of the cavernous nerve (CN) and erectile dysfunction (ED). Return of potency is dependent on axonal regeneration and reinnervation of the penis. Following CN injury (CNI), RhoA and Rho-associated protein kinase (ROCK) increase in penile endothelial and smooth muscle cells. Previous studies indicate that nerve regeneration is hampered by activation of RhoA/ROCK pathway. We evaluated the role of RhoA/ROCK pathway in CN regulation following CNI using a validated rat model. CNI upregulated gene and protein expression of RhoA/ROCK and caspase-3 mediated apoptosis in the major pelvic ganglion (MPG). ROCK inhibitor (ROCK-I) prevented upregulation of RhoA/ROCK pathway as well as activation of caspase-3 in the MPG. Following CNI, there was decrease in the dimer to monomer ratio of neuronal nitric oxide synthase (nNOS) protein and lowered NOS activity in the MPG, which were prevented by ROCK-I. CNI lowered intracavernous pressure and impaired non-adrenergic non-cholinergic-mediated relaxation in the penis, consistent with ED. ROCK-I maintained the intracavernous pressure and non-adrenergic non-cholinergic-mediated relaxation in the penis following CNI. These results suggest that activation of RhoA/ROCK pathway mediates caspase-3 dependent apoptosis of nitrergic neurons in the MPG following CNI and that ROCK-I can prevent post-prostatectomy ED. PMID:27388816

  17. 抗神经生长因子抗体对大鼠慢性坐骨神经压迫损伤模型的脊髓胶质细胞激活的抑制作用%Anti-nerve Growth Factor Antibody Inhibits the Spinal Cord Glial Cell Activation in Rats Model of Chronic Constriction Injury

    Institute of Scientific and Technical Information of China (English)

    李棋; 麻伟青; 王慧明; 董发团; 杨云丽; 李文锋

    2012-01-01

    Objective To investigate the effects of anti-nerve growth factor antibody (anti-NGF) on the pain behavior and the spinal astrocyte activation in rats model of chronic constriction sciatic nerve injury (CCI) . Methods Chronic sciatic nerve compression injury (chronic constriction injury, CCD model was prepared by surgery in rats. The experimental rats were randomly divided into four groups: the CCI + anti- NGF group (n = 8) . rats were given daily single intraperitoneal injection of anti-NGF (10 mg/kg) at 7th day after surgery; the CCI model + saline group (n = 8) : rats were given daily single intraperitoneal injection of saline at 7th day after surgery; sham operation anti-NGF group (n =8) and sham operation saline group (n =8) . Mechanical and thermal pain behavior were observed in every another day after surgery within 15 days. 15 days after surgery, rats in each group was perfused by 4% paraformaldehyde, the expression of astrocyte cell marker GFAP in rats'L4- 5- segment spinal cord was observed by immunohistochemical staining. Results Within 3 days after surgery, the CCI model + saline group's mechanical and thermal pain threshold decreased significantly and reached its peak after 7 days. At 7th day after surgery, a single dose of anti- NGF antibody intraperitoneal injection shortly alleviated the mechanical and thermal pain threshold decrease in CCI rats, continuously injection of anti-NGF 7 days significantly improved the mechanical and thermal pain threshold of CCI rats, which was higher than rats in CCI + saline group. The spinal GFAP expression in CCI + anti-NGF group was significantly lower than the CCI + saline group at 15th day after surgery. Conclusions Inrraperitoneal injection of anti-NGF antibody can effectively reverse the pain behavior of the CCI rat model. Continuous injection of anti-NGF can significantly improve the pain behavior in the CCI rat models. In the spinal cord of rats in CCI + anti- NGF group, GFAP expression is significantly lower

  18. Nerves and Anesthesia: A physics perspective on medicine

    CERN Document Server

    Heimburg, Thomas

    2014-01-01

    We present a recent theory for nerve pulse propagation and anesthesia and argue that both nerve activity and the action of anesthetics can be understood on the basis of simple physical laws. It was found experimentally that biological membranes melt from a solid state to a liquid state just below physiological temperature. Such melting processes have a profound influence on the physical properties of cell membranes. They make it possible for mechanical pulses (solitons) to travel along nerve axons. In these pulses, a region of solid phase travels in the liquid nerve membrane. These pulses display many properties associated with the action potential in nerves. Both general and local anesthetics lower melting temperatures of membranes. Thus, they make it more difficult to excite the nerve membrane. Since hydrostatic pressure increases melting temperatures, it counteracts anesthesia. This theory has the virtue of providing a simple explanation of the famous Meyer-Overton correlation, which states that the effect...

  19. Hydrogen-rich saline promotes survival of retinal ganglion cells in a rat model of optic nerve crush.

    Directory of Open Access Journals (Sweden)

    Jing-chuan Sun

    Full Text Available OBJECTIVE: To investigate the effect of molecular hydrogen (H2 in a rat model subjected to optic nerve crush (ONC. METHODS: We tested the hypothesis that after optic nerve crush (ONC, retinal ganglion cell (RGC could be protected by H₂. Rats in different groups received saline or hydrogen-rich saline every day for 14 days after ONC. Retinas from animals in each group underwent measurements of hematoxylin and eosin (H&E staining, cholera toxin beta (CTB tracing, gamma synuclein staining, and terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling (TUNEL staining 2 weeks post operation. Flash visual evoked potentials (FVEP and pupillary light reflex (PLR were then tested to evaluate the function of optic nerve. The malondialdehyde (MDA level in retina was evaluated. RESULTS: H&E, gamma synuclein staining and CTB tracing showed that the survival rate of RGCs in hydrogen saline-treated group was significantly higher than that in saline-treated group. Apoptosis of RGCs assessed by TUNEL staining were less observed in hydrogen saline-treated group. The MDA level in retina of H₂ group was much lower than that in placebo group. Furthermore, animals treated with hydrogen saline showed better function of optic nerve in assessments of FVEP and PLR. CONCLUSION: These results demonstrated that H₂ protects RGCs and helps preserve the visual function after ONC and had a neuroprotective effect in a rat model subjected to ONC.

  20. Retinal nerve fiber layer and ganglion cell complex thickness in patients with type 2 diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Mehmet Demir

    2014-01-01

    Full Text Available Aim: The aim of the following study is to evaluate the retinal nerve fiber layer (RNFL and ganglion cell complex (GCC thickness in patients with type 2 diabetes mellitus (DM. Materials and Methods: Average, inferior, and superior values of RNFL and GCC thickness were measured in 123 patients using spectral domain optical coherence tomography. The values of participants with DM were compared to controls. Diabetic patients were collected in Groups 1, 2 and 3. Group 1 = 33 participants who had no diabetic retinopathy (DR; Group 2 = 30 participants who had mild nonproliferative DR and Group 3 = 30 participants who had moderate non-proliferative DR. The 30 healthy participants collected in Group 4. Analysis of variance test and a multiple linear regression analysis were used for statistical analysis. Results: The values of RNFL and GCC in the type 2 diabetes were thinner than controls, but this difference was not statistically significant. Conclusions: This study showed that there is a nonsignificant loss of RNFL and GCC in patients with type 2 diabetes.

  1. Microencapsulation improves inhibitory effects of transplanted olfactory ensheathing cells on pain after sciatic nerve injury

    Institute of Scientific and Technical Information of China (English)

    Hao Zhao; Qing Li; Bao-lin Yang; Zeng-xu Liu; Qing Yu; Wen-jun Zhang; Keng Yuan; Hui-hong Zeng; Gao-chun Zhu; De-ming Liu

    2015-01-01

    Olfactory bulb tissue transplantation inhibits P2X2/3 receptor-mediated neuropathic pain. However, the olfactory bulb has a complex cellular composition, and the mechanism underlying the action of puriifed transplanted olfactory ensheathing cells (OECs) remains unclear. In the present study, we microencapsulated OECs in alginic acid, and transplanted free and microen-capsulated OECs into the region surrounding the injured sciatic nerve in rat models of chronic constriction injury. We assessed mechanical nociception in the rat models 7 and 14 days after surgery by measuring paw withdrawal threshold, and examined P2X2/3 receptor expression in L4–5 dorsal root ganglia using immunohistochemistry. Rats that received free and microencap-sulated OEC transplants showed greater withdrawal thresholds than untreated model rats, and weaker P2X2/3 receptor immunoreactivity in dorsal root ganglia. At 14 days, paw withdrawal threshold was much higher in the microencapsulated OEC-treated animals. Our results conifrm that microencapsulated OEC transplantation suppresses P2X2/3 receptor expression in L4–5 dorsal root ganglia in rat models of neuropathic pain and reduces allodynia, and also suggest that transplantation of microencapsulated OECs is more effective than transplantation of free OECs for the treatment of neuropathic pain.

  2. Dorsal root ganglion-derived Schwann cells combined with poly(lactic-co-glycolic acid)/chitosan conduits for the repair of sciatic nerve defects in rats.

    Science.gov (United States)

    Zhao, Li; Qu, Wei; Wu, Yuxuan; Ma, Hao; Jiang, Huajun

    2014-11-15

    Schwann cells, nerve regeneration promoters in peripheral nerve tissue engineering, can be used to repair both the peripheral and central nervous systems. However, isolation and purification of Schwann cells are complicated by contamination with fibroblasts. Current reported measures are mainly limited by either high cost or complicated procedures with low cell yields or purity. In this study, we collected dorsal root ganglia from neonatal rats from which we obtained highly purified Schwann cells using serum-free melanocyte culture medium. The purity of Schwann cells (> 95%) using our method was higher than that using standard medium containing fetal bovine serum. The obtained Schwann cells were implanted into poly(lactic-co-glycolic acid)/chitosan conduits to repair 10-mm sciatic nerve defects in rats. Results showed that axonal diameter and area were significantly increased and motor functions were obviously improved in the rat sciatic nerve tissue. Experimental findings suggest that serum-free melanocyte culture medium is conducive to purify Schwann cells and poly(lactic-co-glycolic acid)/chitosan nerve conduits combined with Schwann cells contribute to restore sciatic nerve defects.

  3. Dorsal root ganglion-derived Schwann cells combined with poly(lactic-co-glycolic acid)/chitosan conduits for the repair of sciatic nerve defects in rats

    Institute of Scientific and Technical Information of China (English)

    Li Zhao; Wei Qu; Yuxuan Wu; Hao Ma; Huajun Jiang

    2014-01-01

    Schwann cells, nerve regeneration promoters in peripheral nerve tissue engineering, can be used to repair both the peripheral and central nervous systems. However, isolation and puriifcation of Schwann cells are complicated by contamination with ifbroblasts. Current reported measures are mainly limited by either high cost or complicated procedures with low cell yields or purity. In this study, we collected dorsal root ganglia from neonatal rats from which we obtained highly puriifed Schwann cells using serum-free melanocyte culture medium. The purity of Schwann cells (> 95%) using our method was higher than that using standard medium containing fetal bovine serum. The obtained Schwann cells were implanted into poly(lactic-co-glycolic acid)/chi-tosan conduits to repair 10-mm sciatic nerve defects in rats. Results showed that axonal diameter and area were signiifcantly increased and motor functions were obviously improved in the rat sciatic nerve tissue. Experimental ifndings suggest that serum-free melanocyte culture medium is conducive to purify Schwann cells and poly(lactic-co-glycolic acid)/chitosan nerve conduits combined with Schwann cells contribute to restore sciatic nerve defects.

  4. Tumors of the optic nerve

    DEFF Research Database (Denmark)

    Lindegaard, Jens; Heegaard, Steffen

    2009-01-01

    A variety of lesions may involve the optic nerve. Mainly, these lesions are inflammatory or vascular lesions that rarely necessitate surgery but may induce significant visual morbidity. Orbital tumors may induce proptosis, visual loss, relative afferent pupillary defect, disc edema and optic...... atrophy, but less than one-tenth of these tumors are confined to the optic nerve or its sheaths. No signs or symptoms are pathognomonic for tumors of the optic nerve. The tumors of the optic nerve may originate from the optic nerve itself (primary tumors) as a proliferation of cells normally present...... in the nerve (e.g., astrocytes and meningothelial cells). The optic nerve may also be invaded from tumors originating elsewhere (secondary tumors), invading the nerve from adjacent structures (e.g., choroidal melanoma and retinoblastoma) or from distant sites (e.g., lymphocytic infiltration and distant...

  5. The Effects of Phrenic Nerve Degeneration by Axotomy and Crush on the Electrical Activities of Diaphragm Muscles of Rats.

    Science.gov (United States)

    Alkiş, Mehmet Eşref; Kavak, Servet; Sayır, Fuat; Him, Aydin

    2016-03-01

    The aim of this study was to investigate the effect of axotomy and crush-related degeneration on the electrical activities of diaphragm muscle strips of experimental rats. In the present study, twenty-one male Wistar-albino rats were used and divided into three groups. The animals in the first group were not crushed or axotomized and served as controls. Phrenic nerves of the rats in the second and third groups were crushed or axotomized in the diaphragm muscle. Resting membrane potential (RMP) was decreased significantly in both crush and axotomy of diaphragm muscle strips of experimental rats (p crush and axotomy rats (p Crushing or axotomizing the phrenic nerves may produce electrical activities in the diaphragm muscle of the rat by depolarization time and half-repolarization time prolonged in crush and axotomy rats. PMID:26972299

  6. Engrafted human induced pluripotent stem cell-derived anterior specified neural progenitors protect the rat crushed optic nerve.

    Directory of Open Access Journals (Sweden)

    Leila Satarian

    Full Text Available BACKGROUND: Degeneration of retinal ganglion cells (RGCs is a common occurrence in several eye diseases. This study examined the functional improvement and protection of host RGCs in addition to the survival, integration and neuronal differentiation capabilities of anterior specified neural progenitors (NPs following intravitreal transplantation. METHODOLOGY/PRINCIPAL FINDINGS: NPs were produced under defined conditions from human induced pluripotent stem cells (hiPSCs and transplanted into rats whose optic nerves have been crushed (ONC. hiPSCs were induced to differentiate into anterior specified NPs by the use of Noggin and retinoic acid. The hiPSC-NPs were labeled by green fluorescent protein or a fluorescent tracer 1,1' -dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI and injected two days after induction of ONC in hooded rats. Functional analysis according to visual evoked potential recordings showed significant amplitude recovery in animals transplanted with hiPSC-NPs. Retrograde labeling by an intra-collicular DiI injection showed significantly higher numbers of RGCs and spared axons in ONC rats treated with hiPSC-NPs or their conditioned medium (CM. The analysis of CM of hiPSC-NPs showed the secretion of ciliary neurotrophic factor, basic fibroblast growth factor, and insulin-like growth factor. Optic nerve of cell transplanted groups also had increased GAP43 immunoreactivity and myelin staining by FluoroMyelin™ which imply for protection of axons and myelin. At 60 days post-transplantation hiPSC-NPs were integrated into the ganglion cell layer of the retina and expressed neuronal markers. CONCLUSIONS/SIGNIFICANCE: The transplantation of anterior specified NPs may improve optic nerve injury through neuroprotection and differentiation into neuronal lineages. These NPs possibly provide a promising new therapeutic approach for traumatic optic nerve injuries and loss of RGCs caused by other diseases.

  7. Matured Hop Bittering Components Induce Thermogenesis in Brown Adipose Tissue via Sympathetic Nerve Activity.

    Directory of Open Access Journals (Sweden)

    Yumie Morimoto-Kobayashi

    Full Text Available Obesity is the principal symptom of metabolic syndrome, which refers to a group of risk factors that increase the likelihood of atherosclerosis. In recent decades there has been a sharp rise in the incidence of obesity throughout the developed world. Iso-α-acids, the bitter compounds derived from hops in beer, have been shown to prevent diet-induced obesity by increasing lipid oxidation in the liver and inhibition of lipid absorption from the intestine. Whereas the sharp bitterness induced by effective dose of iso-α-acids precludes their acceptance as a nutrient, matured hop bittering components (MHB appear to be more agreeable. Therefore, we tested MHB for an effect on ameliorating diet-induced body fat accumulation in rodents. MHB ingestion had a beneficial effect but, compared to iso-α-acids and despite containing structurally similar compounds, acted via different mechanisms to reduce body fat accumulation. MHB supplementation significantly reduced body weight gain, epididymal white adipose tissue weight, and plasma non-esterified free fatty acid levels in diet-induced obese mice. We also found that uncoupling protein 1 (UCP1 expression in brown adipose tissue (BAT was significantly increased in MHB-fed mice at both the mRNA and protein levels. In addition, MHB administration in rats induced the β-adrenergic signaling cascade, which is related to cAMP accumulation in BAT, suggesting that MHB could modulate sympathetic nerve activity innervating BAT (BAT-SNA. Indeed, single oral administration of MHB elevated BAT-SNA in rats, and this elevation was dissipated by subdiaphragmatic vagotomy. Single oral administration of MHB maintained BAT temperature at a significantly higher level than in control rats. Taken together, these findings indicate that MHB ameliorates diet-induced body fat accumulation, at least partly, by enhancing thermogenesis in BAT via BAT-SNA activation. Our data suggests that MHB is a useful tool for developing functional

  8. Nerve growth factor alters the sensitivity of rat masseter muscle mechanoreceptors to NMDA receptor activation.

    Science.gov (United States)

    Wong, Hayes; Dong, Xu-Dong; Cairns, Brian E

    2014-11-01

    Intramuscular injection of nerve growth factor (NGF) into rat masseter muscle induces a local mechanical sensitization that is greater in female than in male rats. The duration of NGF-induced sensitization in male and female rats was associated with an increase in peripheral N-methyl-d-aspartate (NMDA) receptor expression by masseter muscle afferent fibers that began 3 days postinjection. Here, we investigated the functional consequences of increased NMDA expression on the response properties of masseter muscle mechanoreceptors. In vivo extracellular single-unit electrophysiological recordings of trigeminal ganglion neurons innervating the masseter muscle were performed in anesthetized rats 3 days after NGF injection (25 μg/ml, 10 μl) into the masseter muscle. Mechanical activation threshold was assessed before and after intramuscular injection of NMDA. NMDA injection induced mechanical sensitization in both sexes that was increased significantly following NGF injection in the male rats but not in the female rats. However, in female but not male rats, further examination found that preadministration of NGF induced a greater sensitization in slow Aδ-fibers (2-7 m/s) than fast Aδ-fibers (7-12 m/s). This suggests that preadministration of NGF had a different effect on slowly conducting mechanoreceptors in the female rats compared with the male rats. Although previous studies have found an association between estrogenic tone and NMDA activity, no correlation was observed between NMDA-evoked mechanical sensitization and plasma estrogen level. This study suggests NGF alters NMDA-induced mechanical sensitization in the peripheral endings of masseter mechanoreceptors in a sexually dimorphic manner.

  9. Long-term delivery of nerve growth factor by encapsulated cell biodelivery in the Göttingen minipig basal forebrain

    DEFF Research Database (Denmark)

    Fjord-Larsen, L; Kusk, P; Tornøe, Jens;

    2010-01-01

    Nerve growth factor (NGF) prevents cholinergic degeneration in Alzheimer's disease (AD) and improves memory in AD animal models. In humans, the safe delivery of therapeutic doses of NGF is challenging. For clinical use, we have therefore developed an encapsulated cell (EC) biodelivery device......, capable of local delivery of NGF. The clinical device, named NsG0202, houses an NGF-secreting cell line (NGC-0295), which is derived from a human retinal pigment epithelial (RPE) cell line, stably genetically modified to secrete NGF. Bioactivity and correct processing of NGF was confirmed in vitro. Ns...

  10. Effects of collagen membranes enriched with in vitro-differentiated N1E-115 cells on rat sciatic nerve regeneration after end-to-end repair

    Directory of Open Access Journals (Sweden)

    Fornaro Michele

    2010-02-01

    Full Text Available Abstract Peripheral nerves possess the capacity of self-regeneration after traumatic injury but the extent of regeneration is often poor and may benefit from exogenous factors that enhance growth. The use of cellular systems is a rational approach for delivering neurotrophic factors at the nerve lesion site, and in the present study we investigated the effects of enwrapping the site of end-to-end rat sciatic nerve repair with an equine type III collagen membrane enriched or not with N1E-115 pre-differentiated neural cells. After neurotmesis, the sciatic nerve was repaired by end-to-end suture (End-to-End group, end-to-end suture enwrapped with an equine collagen type III membrane (End-to-EndMemb group; and end-to-end suture enwrapped with an equine collagen type III membrane previously covered with neural cells pre-differentiated in vitro from N1E-115 cells (End-to-EndMembCell group. Along the postoperative, motor and sensory functional recovery was evaluated using extensor postural thrust (EPT, withdrawal reflex latency (WRL and ankle kinematics. After 20 weeks animals were sacrificed and the repaired sciatic nerves were processed for histological and stereological analysis. Results showed that enwrapment of the rapair site with a collagen membrane, with or without neural cell enrichment, did not lead to any significant improvement in most of functional and stereological predictors of nerve regeneration that we have assessed, with the exception of EPT which recovered significantly better after neural cell enriched membrane employment. It can thus be concluded that this particular type of nerve tissue engineering approach has very limited effects on nerve regeneration after sciatic end-to-end nerve reconstruction in the rat.

  11. Negative impact of AQP-4 channel inhibition on survival of retinal ganglion cells and glutamate metabolism after crushing optic nerve.

    Science.gov (United States)

    Nishikawa, Yuko; Oku, Hidehiro; Morishita, Seita; Horie, Taeko; Kida, Teruyo; Mimura, Masashi; Fukumoto, Masanori; Kojima, Shota; Ikeda, Tsunehiko

    2016-05-01

    The purpose of this study was to determine whether inhibition of aquaporin 4 (AQP4) is neuroprotective or neurodestructive after crushing the optic nerve of rats. The left optic nerves of rats were crushed, and TGN-020 (5.0 mg/kg, crush TGN-020) or its vehicle (DMSO, crush placebo) was injected intraperitoneally just after the crushing. As controls, the left optic nerves were exposed but not touched in other rats (sham controls). The retinal damages were determined by the density of retinal ganglion cells (RGCs) and the ratio of BAX/Bcl-2 on day 7. The glutamate level in the optic nerve on day 1 after the crushing was determined. The expressions of glutamine synthetase, glutamate-aspartate transporter (GLAST), and AQP4 were determined on day 3 by immunoblotting. The effects of AQP4 inhibition on the glutamate-induced changes of AQP4 expression and on the glutamate uptake were determined for optic nerve astrocytes in culture. The results showed that the density of RGCs was 2040 ± 91.3 cells/mm(2) (n = 6) in the sham control, and it was significantly decreased to 1072 ± 134.3 cells/mm(2) after crushing the optic nerve (P crush placebo, n = 7; Fisher). An intraperitoneal injection of TGN-020 led to a further significant (P = 0.02, Fisher) decrease of the density of RGCs to 743 ± 371 cells/mm(2) (crush TGN-020, n = 7). The mRNA level of BAX/Bcl-2 ratio was 0.37 ± 0.05 in the sham control (n = 6) which was significantly increased to 0.88 ± 0.10 after crushing the optic nerve (placebo crush, n = 7; P = 0.0001, Scheffe). TGN-020 also significantly increased the BAX/Bcl-2 ratio to 1.29 ± 0.4 (n = 6) from the crush placebo group (P = 0.04, Scheffe). Immunoblotting showed similar changes in the protein levels. The glutamate level in the optic nerve was significantly increased to 53.7 ± 6.0 μM/mg/protein on day 1 (n = 4) from the sham control level of 45.9 ± 3.1 μM/mg/protein (n = 4; P = 0.04, t test). TGN-020

  12. Feasibility of Human Amniotic Fluid Derived Stem Cells in Alleviation of Neuropathic Pain in Chronic Constrictive Injury Nerve Model.

    Directory of Open Access Journals (Sweden)

    Chien-Yi Chiang

    Full Text Available The neurobehavior of neuropathic pain by chronic constriction injury (CCI of sciatic nerve is very similar to that in humans, and it is accompanied by a profound local inflammation response. In this study, we assess the potentiality of human amniotic fluid derived mesenchymal stem cells (hAFMSCs for alleviating the neuropathic pain in a chronic constriction nerve injury model.This neuropathic pain animal model was conducted by four 3-0 chromic gut ligatures loosely ligated around the left sciatic nerve in Sprague-Dawley rats. The intravenous administration of hAFMSCs with 5x105 cells was conducted for three consecutive days.The expression IL-1β, TNF-α and synaptophysin in dorsal root ganglion cell culture was remarkably attenuated when co-cultured with hAFMSCs. The significant decrease of PGP 9.5 in the skin after CCI was restored by administration of hAFMSCs. Remarkably increased expression of CD 68 and TNF-α and decreased S-100 and neurofilament expression in injured nerve were rescued by hAFMSCs administration. Increases in synaptophysin and TNF-α over the dorsal root ganglion were attenuated by hAFMSCs. Significant expression of TNF-α and OX-42 over the dorsal spinal cord was substantially attenuated by hAFMSCs. The increased amplitude of sensory evoked potential as well as expression of synaptophysin and TNF-α expression was alleviated by hAFMSCs. Human AFMSCs significantly improved the threshold of mechanical allodynia and thermal hyperalgesia as well as various parameters of CatWalk XT gait analysis.Human AFMSCs administration could alleviate the neuropathic pain demonstrated in histomorphological alteration and neurobehavior possibly through the modulation of the inflammatory response.

  13. Effect of alpha lipoic acid on retinal ganglion cell survival in an optic nerve crush model

    Science.gov (United States)

    Liu, Ruixing; Wang, Yanling; Pu, Mingliang

    2016-01-01

    Purpose This study was conducted to determine whether alpha lipoic acid (ALA) promotes the survival of retinal ganglion cells (RGCs) in a rat model of optic nerve crush (ONC) injury and to investigate the neuroprotective mechanisms of ALA in the retina in this ONC injury model. Methods Adult male Sprague-Dawley rats (180–220 g) were subjected to ONC injury surgery. ALA (63 mg/kg) was injected intravenously 1 day before or after the ONC injury. Animals were euthanized after 10 days, and the number of ganglion cells positive for RNA-binding protein with multiple splicing (Rbpms), which is an RGC marker, were counted on the whole mount retinas. In addition, immunofluorescence and immunoblotting were performed to examine the localization and levels of erythropoietin receptor (EPOR) and neurotrophin-4/5 (NT4/5) in the retinas in all experimental groups. To determine whether the EPO/EPOR signaling pathway was involved in the ALA antioxidant pathway, the rats were subjected to ruxolitinib (INCB018424, 0.25 mg/kg, bid, intraperitoneal, i.p.) treatment after the animals were injected intravenously with ALA 1 day before ONC injury. Results The average number of Rbpms-positive cells/mm2 in the control group (sham-operated group), the ONC group, the ALA-ONC group, and the ONC-ALA group retinas was 2219±28, 418±8, 848±22, and 613±18/mm2, respectively. The ALA-ONC and ONC-ALA groups showed a statistically significantly increased RGC survival rate compared to the ONC group. There were statistical differences in the RGC survival rates between the ALA-ONC (39%) and ONC-ALA groups (28%; p<0.05). Immunofluorescent labeling showed that EPOR and NT4/5 expression was significant in the retinal ganglion cell layer (GCL). At the same time, western blot analysis revealed that ALA induced upregulation of EPOR protein and NT4/5 protein expression in the retina after ONC injury. However, INCB018424 reversed the protective effects of ALA on the ONC retinas. Conclusions ALA has

  14. Augmented supraorbital skin sympathetic nerve activity responses to symptom trigger events in rosacea patients.

    Science.gov (United States)

    Metzler-Wilson, Kristen; Toma, Kumika; Sammons, Dawn L; Mann, Sarah; Jurovcik, Andrew J; Demidova, Olga; Wilson, Thad E

    2015-09-01

    Facial flushing in rosacea is often induced by trigger events. However, trigger causation mechanisms are currently unclear. This study tested the central hypothesis that rosacea causes sympathetic and axon reflex-mediated alterations resulting in trigger-induced symptomatology. Twenty rosacea patients and age/sex-matched controls participated in one or a combination of symptom triggering stressors. In protocol 1, forehead skin sympathetic nerve activity (SSNA; supraorbital microneurography) was measured during sympathoexcitatory mental (2-min serial subtraction of novel numbers) and physical (2-min isometric handgrip) stress. In protocol 2, forehead skin blood flow (laser-Doppler flowmetry) and transepithelial water loss/sweat rate (capacitance hygrometry) were measured during sympathoexcitatory heat stress (whole body heating by perfusing 50°C water through a tube-lined suit). In protocol 3, cheek, forehead, forearm, and palm skin blood flow were measured during nonpainful local heating to induce axon reflex vasodilation. Heart rate (HR) and mean arterial pressure (MAP) were recorded via finger photoplethysmography to calculate cutaneous vascular conductance (CVC; flux·100/MAP). Higher patient transepithelial water loss was observed (rosacea 0.20 ± 0.02 vs. control 0.10 ± 0.01 mg·cm(-2)·min(-1), P MAP changes were not different between groups during sympathoexcitatory stressors or local heating. SSNA during early mental (32 ± 9 and 9 ± 4% increase) and physical (25 ± 4 and 5 ± 1% increase, rosacea and controls, respectively) stress was augmented in rosacea (both P < 0.05). Heat stress induced more rapid sweating and cutaneous vasodilation onset in rosacea compared with controls. No axon reflex vasodilation differences were observed between groups. These data indicate that rosacea affects SSNA and that hyperresponsiveness to trigger events appears to have a sympathetic component. PMID:26133800

  15. Role of endothelin-1 in mediating changes in cardiac sympathetic nerve activity in heart failure.

    Science.gov (United States)

    Abukar, Yonis; May, Clive N; Ramchandra, Rohit

    2016-01-01

    Heart failure (HF) is associated with increased sympathetic nerve activity to the heart (CSNA), which is directly linked to mortality in HF patients. Previous studies indicate that HF is associated with high levels of plasma endothelin-1 (ET-1), which correlates with the severity of the disease. We hypothesized that blockade of endothelin receptors would decrease CSNA. The effects of intravenous tezosentan (a nonselective ETA and ETB receptor antagonist) (8 mg·kg(-1)·h(-1)) on resting levels of CSNA, arterial pressure, and heart rate were determined in conscious normal sheep (n = 6) and sheep with pacing-induced HF (n = 7). HF was associated with a significant decrease in ejection fraction (from 74 ± 2% to 38 ± 1%, P < 0.001) and a significant increase in resting levels of CSNA burst incidence (from 56 ± 11 to 87 ± 2 bursts/100 heartbeats, P < 0.01). Infusion of tezosentan for 60 min significantly decreased resting mean aterial pressure (MAP) in both normal and HF sheep (-8 ± 4 mmHg and -4 ± 3 mmHg, respectively; P < 0.05). This was associated with a significant decrease in CSNA (by 25 ± 26% of control) in normal sheep, but there was no change in CSNA in HF sheep. Calculation of spontaneous baroreflex gain indicated significant impairment of the baroreflex control of HR after intravenous tezosentan infusion in normal animals but no change in HF animals. These data suggest that endogenous levels of ET-1 contribute to the baseline levels of CSNA in normal animals, but this effect is absent in HF.

  16. Chitosan/silk fibroin-based, Schwann cell-derived extracellular matrix-modified scaffolds for bridging rat sciatic nerve gaps.

    Science.gov (United States)

    Gu, Yun; Zhu, Jianbin; Xue, Chengbin; Li, Zhenmeiyu; Ding, Fei; Yang, Yumin; Gu, Xiaosong

    2014-02-01

    Extracellular matrix (ECM) plays a prominent role in establishing and maintaining an ideal microenvironment for tissue regeneration, and ECM scaffolds are used as a feasible alternative to cellular and molecular therapy in the fields of tissue engineering. Because of their advantages over tissue-derived ECM scaffolds, cultured cell-derived ECM scaffolds are beginning to attract attention, but they have been scarcely studied for peripheral nerve repair. Here we aimed to develop a tissue engineered nerve scaffold by reconstituting nerve cell-derived ECM with natural biomaterials. A protocol was adopted to prepare and characterize the cultured Schwann cell (SC)-derived ECM. A chitosan conduit and silk fibroin (SF) fibers were prepared, cultured with SCs for ECM deposition, and subjected to decellularization, followed by assembly into a chitosan/SF-based, SC-derived ECM-modified scaffold, which was used to bridge a 10 mm rat sciatic nerve gap. The results from morphological analysis as well as electrophysiological examination indicated that regenerative outcomes achieved by our developed scaffold were similar to those by an acellular nerve graft (namely a nerve tissue-derived ECM scaffold), but superior to those by a plain chitosan/SF scaffold. Moreover, blood and histopathological parameters confirmed the safety of scaffold modification by SC-derived ECM. Therefore, a hybrid scaffold based on joint use of acellular and classical biomaterials represents a promising approach to nerve tissue engineering. PMID:24360577

  17. Neural Stem Cell Affinity of Chitosan and Feasibility of Chitosan-Based Porous Conduits as Scaffolds for Nerve Tissue Engineering

    Institute of Scientific and Technical Information of China (English)

    WANG Aijun; AO Qiang; HE Qing; GONG Xiaoming; GONG Kai; GONG Yandao; ZHAO Nanming; ZHANG Xiufang

    2006-01-01

    Neural stem cells (NSCs) are currently considered as powerful candidate seeding cells for regeneration of both spinal cords and peripheral nerves. In this study, NSCs derived from fetal rat cortices were co-cultured with chitosan to evaluate the cell affinity of this material. The results showed that NSCs grew and proliferated well on chitosan films and most of them differentiated into neuron-like cells after 4 days of culture. Then, molded and braided chitosan conduits were fabricated and characterized for their cytotoxicity, swelling, and mechanical properties. Both types of conduits had no cytotoxic effects on fibroblasts (L929 cells) or neuroblastoma (Neuro-2a) cells. The molded conduits are much softer and more flexible while the braided conduits possess much better mechanical properties, which suggests different potential applications.

  18. Central muscarinic cholinergic activation alters interaction between splenic dendritic cell and CD4+CD25- T cells in experimental colitis.

    Directory of Open Access Journals (Sweden)

    Peris Munyaka

    Full Text Available BACKGROUND: The cholinergic anti-inflammatory pathway (CAP is based on vagus nerve (VN activity that regulates macrophage and dendritic cell responses in the spleen through alpha-7 nicotinic acetylcholine receptor (a7nAChR signaling. Inflammatory bowel disease (IBD patients present dysautonomia with decreased vagus nerve activity, dendritic cell and T cell over-activation. The aim of this study was to investigate whether central activation of the CAP alters the function of dendritic cells (DCs and sequential CD4+/CD25-T cell activation in the context of experimental colitis. METHODS: The dinitrobenzene sulfonic acid model of experimental colitis in C57BL/6 mice was used. Central, intracerebroventricular infusion of the M1 muscarinic acetylcholine receptor agonist McN-A-343 was used to activate CAP and vagus nerve and/or splenic nerve transection were performed. In addition, the role of α7nAChR signaling and the NF-kB pathway was studied. Serum amyloid protein (SAP-A, colonic tissue cytokines, IL-12p70 and IL-23 in isolated splenic DCs, and cytokines levels in DC-CD4+CD25-T cell co-culture were determined. RESULTS: McN-A-343 treatment reduced colonic inflammation associated with decreased pro-inflammatory Th1/Th17 colonic and splenic cytokine secretion. Splenic DCs cytokine release was modulated through α7nAChR and the NF-kB signaling pathways. Cholinergic activation resulted in decreased CD4+CD25-T cell priming. The anti-inflammatory efficacy of central cholinergic activation was abolished in mice with vagotomy or splenic neurectomy. CONCLUSIONS: Suppression of splenic immune cell activation and altered interaction between DCs and T cells are important aspects of the beneficial effect of brain activation of the CAP in experimental colitis. These findings may lead to improved therapeutic strategies in the treatment of IBD.

  19. Pro-nerve growth factor induces autocrine stimulation of breast cancer cell invasion through tropomyosin-related kinase A (TrkA) and sortilin protein.

    Science.gov (United States)

    Demont, Yohann; Corbet, Cyril; Page, Adeline; Ataman-Önal, Yasemin; Choquet-Kastylevsky, Genevieve; Fliniaux, Ingrid; Le Bourhis, Xuefen; Toillon, Robert-Alain; Bradshaw, Ralph A; Hondermarck, Hubert

    2012-01-13

    The precursor of nerve growth factor (proNGF) has been described as a biologically active polypeptide able to induce apoptosis in neuronal cells, via the neurotrophin receptor p75(NTR) and the sortilin receptor. Herein, it is shown that proNGF is produced and secreted by breast cancer cells, stimulating their invasion. Using Western blotting and mass spectrometry, proNGF was detected in a panel of breast cancer cells as well as in their conditioned media. Immunohistochemical analysis indicated an overproduction of proNGF in breast tumors, when compared with benign and normal breast biopsies, and a relationship to lymph node invasion in ductal carcinomas. Interestingly, siRNA against proNGF induced a decrease of breast cancer cell invasion that was restored by the addition of non-cleavable proNGF. The activation of TrkA, Akt, and Src, but not the MAP kinases, was observed. In addition, the proNGF invasive effect was inhibited by the Trk pharmacological inhibitor K252a, a kinase-dead TrkA, and siRNA against TrkA sortilin, neurotensin, whereas siRNA against p75(NTR) and the MAP kinase inhibitor PD98059 had no impact. These data reveal the existence of an autocrine loop stimulated by proNGF and mediated by TrkA and sortilin, with the activation of Akt and Src, for the stimulation of breast cancer cell invasion.

  20. Chitosan crosslinked flat scaffolds for peripheral nerve regeneration.

    Science.gov (United States)

    Fregnan, F; Ciglieri, E; Tos, P; Crosio, A; Ciardelli, G; Ruini, F; Tonda-Turo, C; Geuna, S; Raimondo, S

    2016-01-01

    Chitosan (CS) has been widely used in a variety of biomedical applications, including peripheral nerve repair, due to its excellent biocompatibility, biodegradability, readily availability and antibacterial activity. In this study, CS flat membranes, crosslinked with dibasic sodium phosphate (DSP) alone (CS/DSP) or in association with the γ-glycidoxypropyltrimethoxysilane (CS/GPTMS_DSP), were fabricated with a solvent casting technique. The constituent ratio of crosslinking agents and CS were previously selected to obtain a composite material having both adequate mechanical properties and high biocompatibility. In vitro cytotoxicity tests showed that both CS membranes allowed cell survival and proliferation. Moreover, CS/GPTMS_DSP membranes promoted cell adhesion, induced Schwann cell-like morphology and supported neurite outgrowth from dorsal root ganglia explants. Preliminary in vivo tests carried out on both types of nerve scaffolds (CS/DSP and CS/GPTMS_DSP membranes) demonstrated their potential for: (i) protecting, as a membrane, the site of nerve crush or repair by end-to-end surgery and avoiding post-operative nerve adhesion; (ii) bridging, as a conduit, the two nerve stumps after a severe peripheral nerve lesion with substance loss. A 1 cm gap on rat median nerve was repaired using CS/DSP and CS/GPTMS_DSP conduits to further investigate their ability to induce nerve regeneration in vivo. CS/GPTMS_DSP tubes resulted to be more fragile during suturing and, along a 12 week post-operative lapse of time, they detached from the distal nerve stump. On the contrary CS/DSP conduits promoted nerve fiber regeneration and functional recovery, leading to an outcome comparable to median nerve repaired by autograft. PMID:27508969

  1. Peripheral nerve pathology, including aberrant Schwann cell differentiation, is ameliorated by doxycycline in a laminin-α2-deficient mouse model of congenital muscular dystrophy

    OpenAIRE

    Homma, Sachiko; Beermann, Mary Lou; Miller, Jeffrey Boone

    2011-01-01

    The most common form of childhood congenital muscular dystrophy, Type 1A (MDC1A), is caused by mutations in the human LAMA2 gene that encodes the laminin-α2 subunit. In addition to skeletal muscle deficits, MDC1A patients typically show a loss of peripheral nerve function. To identify the mechanisms underlying this loss of nerve function, we have examined pathology and cell differentiation in sciatic nerves and ventral roots of the laminin-α2-deficient (Lama2−/−) mice, which are models for MD...

  2. Discrepancy between magnetic resonance imaging and cranial nerve neuropathies associated with the involvement of diffuse large B-cell lymphoma(DLBL)

    OpenAIRE

    Yutaka, TSUTSUMI; Asako, N A K A T A; Souichi,SHIRA TORI; Hiroaki, Y A M ATO; Nobuyuki, EHIRA; Hiroe, K A N A MORI; Takahito, K A W A MURA; Taro, NISHIO; Nobutaka, OGURA

    2007-01-01

    An 83-year-old female developed diffuse large B-cell lymphoma(DLBL) of the left nasal cavity. Complete remission was achieved after two courses of Rituximab and CHOP(R-CHOP) . During the fourth course of R-CHOP, sensory disturbance and palsy of the left face developed. Left trigeminal nerve swelling was observed in magnetic resonance imaging(MRI) followed by double vision in the left eye, and MRI revealed swelling of both trigeminal nerves but not of the abducens nerve. Although the swelling ...

  3. Degenerative Nerve Diseases

    Science.gov (United States)

    Degenerative nerve diseases affect many of your body's activities, such as balance, movement, talking, breathing, and heart function. Many of these diseases are genetic. Sometimes the cause is a medical ...

  4. A simple model of radial nerve injury in the rhesus monkey to evaluate peripheral nerve repair

    OpenAIRE

    Wang, Dong; Huang, Xijun; Fu, Guo; Gu, Liqiang; Liu, Xiaolin; WANG, HONGGANG; Hu, Jun; Yi, Jianhua; Niu, Xiaofeng; Zhu, Qingtang

    2014-01-01

    Current research on bone marrow stem cell transplantation and autologous or xenogenic nerve transplantation for peripheral nerve regeneration has mainly focused on the repair of peripheral nerve defects in rodents. In this study, we established a standardized experimental model of radial nerve defects in primates and evaluated the effect of repair on peripheral nerve injury. We repaired 2.5-cm lesions in the radial nerve of rhesus monkeys by transplantation of autografts, acellular allografts...

  5. Immobilization of cells via activated cell walls

    Energy Technology Data Exchange (ETDEWEB)

    Markt, M.; Kas, J.; Valentova, O.; Demnerova, K.; Vodrazka, Z.

    1986-10-01

    Cell walls of Saccharomyces cerevisiae and S. uvarum were activated by periodate oxidation of vicinal diol groups in cell wall polysaccharides. The aldehyde groups thus generated allow the yeast cells to be covalently bound to modified bead cellulose or macroporous glycidyl methacrylate supports, or to enzymes such as glucose oxidase and catalase. 6 references.

  6. Long-term administration of scopolamine interferes with nerve cell proliferation, differentiation and migration in adult mouse hippocampal dentate gyrus, but it does not induce cell death

    Institute of Scientific and Technical Information of China (English)

    Bing Chun Yan; Yun Lyul Lee; Il-Jun Kang; Moo-Ho Won; Joon Ha Park; Bai Hui Chen; Jeong-Hwi Cho; In Hye Kim; Ji Hyeon Ahn; Jae-Chul Lee; In Koo Hwang; Jun Hwi Cho

    2014-01-01

    Long-term administration of scopolamine, a muscarinic receptor antagonist, can inhibit the survival of newly generated cells, but its effect on the proliferation, differentiation and migration of nerve cells in the adult mouse hippocampal dentate gyrus remain poorly understood. In this study, we used immunohistochemistry and western blot methods to weekly detect the biological behaviors of nerve cells in the hippocampal dentate gyrus of adult mice that received intraperito-neal administration of scopolamine for 4 weeks. Expression of neuronal nuclear antigen (NeuN;a neuronal marker) and Fluoro-Jade B (a marker for the localization of neuronal degeneration) was also detected. After scopolamine treatment, mouse hippocampal neurons did not die, and Ki-67 (a marker for proliferating cells)-immunoreactive cells were reduced in number and reac hed the lowest level at 4 weeks. Doublecortin (DCX; a marker for newly generated neurons)-im-munoreactive cells were gradually shortened in length and reduced in number with time. After scopolamine treatment for 4 weeks, nearly all of the 5-bromo-2′-deoxyuridine (BrdU)-labeled newly generated cells were located in the subgranular zone of the dentate gyrus, but they did not migrate into the granule cell layer. Few mature BrdU/NeuN double-labeled cells were seen in the subgranular zone of the dentate gyrus. These ifndings suggest that long-term administration of scopolamine interferes with the proliferation, differentiation and migration of nerve cells in the adult mouse hippocampal dentate gyrus, but it does not induce cell death.

  7. Non-thermal influence of a weak microwave on nerve fiber activity

    CERN Document Server

    Shneider, M N

    2014-01-01

    This paper presents a short selective review of the non-thermal weak microwave field impact on a nerve fiber. The published results of recent experiments are reviewed and analyzed. The theory of the authors is presented, according to which there are strongly pronounced resonances in the range of about 30-300 GHz associated with the excitation of ultrasonic vibrations in the membrane as a result of interactions with the microwave radiation. These forced vibrations create acoustic pressure, which may lead to the redistribution of the protein transmembrane channels, thus changing the threshold of the action potential excitation in the axons of the neural network. The problem of surface charge on the bilayer lipid membrane of the nerve fiber is discussed. Various experiments for observing the effects considered are also discussed.

  8. Neuroregenerative effects of olfactory ensheathing cells transplanted in a multi-layered conductive nanofibrous conduit in peripheral nerve repair in rats

    OpenAIRE

    Kabiri, Mahboubeh; Oraee-Yazdani, Saeed; Shafiee, Abbas; Hanaee-Ahvaz, Hana; Dodel, Masumeh; Vaseei, Mohammad; Soleimani, Masoud

    2015-01-01

    Background The purpose of this study was to evaluate the efficacy of a multi-layered conductive nanofibrous hollow conduit in combination with olfactory ensheathing cells (OEC) to promote peripheral nerve regeneration. We aimed to harness both the topographical and electrical cues of the aligned conductive nanofibrous single-walled carbon nanotube/ poly (L-lactic acid) (SWCNT/PLLA) scaffolds along with the neurotrophic features of OEC in a nerve tissue engineered approach. Results We demonstr...

  9. Activation of Satellite Glial Cells in Rat Trigeminal Ganglion after Upper Molar Extraction

    International Nuclear Information System (INIS)

    The neurons in the trigeminal ganglion (TG) are surrounded by satellite glial cells (SGCs), which passively support the function of the neurons, but little is known about the interactions between SGCs and TG neurons after peripheral nerve injury. To examine the effect of nerve injury on SGCs, we investigated the activation of SGCs after neuronal damage due to the extraction of the upper molars in rats. Three, 7, and 10 days after extraction, animals were fixed and the TG was removed. Cryosections of the ganglia were immunostained with antibodies against glial fibrillary acidic protein (GFAP), a marker of activated SGCs, and ATF3, a marker of damaged neurons. After tooth extraction, the number of ATF3-immunoreactive (IR) neurons enclosed by GFAP-IR SGCs had increased in a time-dependent manner in the maxillary nerve region of the TG. Although ATF3-IR neurons were not detected in the mandibular nerve region, the number of GFAP-IR SGCs increased in both the maxillary and mandibular nerve regions. Our results suggest that peripheral nerve injury affects the activation of TG neurons and the SGCs around the injured neurons. Moreover, our data suggest the existence of a neuronal interaction between maxillary and mandibular neurons via SGC activation

  10. Activation of stretch-activated channels and maxi-K+ channels by membrane stress of human lamina cribrosa cells.

    LENUS (Irish Health Repository)

    Irnaten, Mustapha

    2009-01-01

    The lamina cribrosa (LC) region of the optic nerve head is considered the primary site of damage in glaucomatous optic neuropathy. Resident LC cells have a profibrotic potential when exposed to cyclical stretch. However, the mechanosensitive mechanisms of these cells remain unknown. Here the authors investigated the effects of membrane stretch on cell volume change and ion channel activity and examined the associated changes in intracellular calcium ([Ca(2+)](i)).

  11. Neuroprotective activity of thioctic acid in central nervous system lesions consequent to peripheral nerve injury.

    OpenAIRE

    Daniele Tomassoni; Francesco Amenta; Lorenzo Di Cesare Mannelli; Carla Ghelardini; Nwankwo, Innocent E.; Alessandra Pacini; Seyed Khosrow Tayebati

    2013-01-01

    Peripheral neuropathies are heterogeneous disorders presenting often with hyperalgesia and allodynia. This study has assessed if chronic constriction injury (CCI) of sciatic nerve is accompanied by increased oxidative stress and central nervous system (CNS) changes and if these changes are sensitive to treatment with thioctic acid. Thioctic acid is a naturally occurring antioxidant existing in two optical isomers (+)- and (−)-thioctic acid and in the racemic form. It has been proposed for tre...

  12. Morphological features of allogenic nerve segment in rats after subcutaneous embedment

    Institute of Scientific and Technical Information of China (English)

    Mingtang Gao; Dianming Jiang

    2006-01-01

    microscope ( × 17 000).MAIN OUTCOME MEASURES: Gross shape, optical and electron microscope results of nerve segments of rats between two groups at 2 weeks after subcutaneous embedment.RESULTS: ① Results of gross observation: Appearance of nerve segment was similar between 2 groups. ②Results of optical observation: medullary sheath denaturation, axonotmesis, vascular engorgement, desmoplasia of adventitia and infiltration of inflammatory cells were all found in both 2 groups. Inflammatory reaction was a little more severe in the allogenic nerve embedment group than in the autologous nerve embedment groups.③Results of electron microscope: Similar cataplasia and denaturation of medullary sheath and cataplasia of Schwann cell were all found in the 2 groups.CONCLUSION: Some inflammatory reaction occurs after allogenic nerve embedment, but the activity of Schwann cell is similar to that of peripheral nerve after autologous nerve embedment.

  13. Repair of sciatic nerve defects with tissue engineered nerves constructed with marrow stromal cells%骨髓间充质细胞构建组织工程神经修复坐骨神经缺损

    Institute of Scientific and Technical Information of China (English)

    何红云; 邓仪昊; 佟晓杰; 成家茂; 杜赵康

    2009-01-01

    BACKGROUND: Schwann calls are seed cells for constructing tissue engineered peripheral nerves. But their in vitro isolation, culture and purification are difficult. Acellular nerve allografts (ANA) have a great effect on repairing peripheral nerve defects, and it can induce marrow stromal cells (MSCs) into Schwann-like calls. Accordingly, MSCs can be used as seed calls theoretically in constructing tissue engineered peripheral nerves, instead of Schwann cells OBJECTIVE: To observe the repairing effect of tissue engineered peripheral nerves constructed with MSCs on sciatic nerve defects and to assess the feasibility of repairing peripheral nerve defects with MSCs as seed calls. DESIGN, TIME AND SE'I-rlNG: A randomized control animal experiment was conducted in the laboratory of Basic Medicine Collage of Dali Collage from July to December in 2008.MATERIALS: A total of 30 SD rats were divided randomly into 3 groups, with 10 in each group. In MSCs+ ANA group, end-to-end anastomosis were performed with 10/0 non traumatic suture to broken ends of rat sciatic nerves and tissue engineered nerves cultured using MSCs combined with ANA; In ANA group, ANA were bridged to broken ends of sciatic nerves; In METHODS: The 10ram sciatic nerve defects in rats were repaired using MSCs-constructed tissue engineered peripheral nerves, whose repairing effects were evaluated at week 12 post transplant through sciatic function index (SFI), gastrocnemius wet weight recovery rate, S-100 immunohistochemical staining and electron microscope observation, etc. MAIN OUTCOME MEASURES: Morphological changes of calls were observed during the culture of compounds; SFI and gastrocnemius wet weight recovery rates were detected after transplantation; New myelinization, axon growth and nerve fiber distdbuUon were observed with toluidine blue staining; Schwann calls growth and nerve fiber regeneration were observed with transmission electron microscope combined with S-100 protein immunohistochemical

  14. Inhibitory Activity of Yokukansankachimpihange against Nerve Growth Factor-Induced Neurite Growth in Cultured Rat Dorsal Root Ganglion Neurons

    Directory of Open Access Journals (Sweden)

    Chiaki Murayama

    2015-08-01

    Full Text Available Chronic pruritus is a major and distressing symptom of many cutaneous diseases, however, the treatment remains a challenge in the clinic. The traditional Chinese-Japanese medicine (Kampo medicine is a conservative and increasingly popular approach to treat chronic pruritus for both patients and medical providers. Yokukansankachimpihange (YKH, a Kampo formula has been demonstrated to be effective in the treatment of itching of atopic dermatitis in Japan although its pharmacological mechanism is unknown clearly. In an attempt to clarify its pharmacological actions, in this study, we focused on the inhibitory activity of YKH against neurite growth induced with nerve growth factor (NGF in cultured rat dorsal root ganglion (DRG neurons because epidermal hyperinnervation is deeply related to itch sensitization. YKH showed approximately 200-fold inhibitory activity against NGF-induced neurite growth than that of neurotropin (positive control, a drug used clinically for treatment of chronic pruritus. Moreover, it also found that Uncaria hook, Bupleurum root and their chemical constituents rhynchophylline, hirsutine, and saikosaponin a, d showed inhibitory activities against NGF-induced neurite growth, suggesting they should mainly contribute to the inhibitory activity of YKH. Further study on the effects of YKH against epidermal nerve density in “itch-scratch” animal models is under investigation.

  15. Differential sensitivity of myosin-heavy-chain-typed fibers to distinct aggregates of nerve-mediated activation.

    Science.gov (United States)

    Dunn, S E; Michel, R N

    1999-02-01

    We studied the regulatory effects of nerve-mediated activity on the early expression of embryonic and adult myosin heavy chains (MHC) within inactive though still innervated rat plantaris and soleus muscle fibers. To this end, we stimulated motor nerves that were quiescent following treatment with tetrodotoxin (TTX) with paradigms designed to partition the influence of neural activation frequency and assessed the selective expression and accumulation of MHCs within muscle fibers using an array of specific antibodies. We show rapid de novo expression of IIx MHC within select soleus fibers in response to high-frequency activation for more than 0.01% of daily time. High-frequency aggregates were also the most effective in preventing the TTX-induced reexpression of embryonic MHCs within specific fibers. Only configurations that included high-frequency trains for more than 0.01% of daily time or combined with 10 Hz stimulation preserved the size of select fibers, used as a measure of the net cellular content of MHC. The effectiveness of this preservation varied according to the muscle type and MHC expressed, and, in a subset of fibers, was influenced by contractile loading status. Our results demonstrate that distinct subsets of MHC-typed fibers are differentially sensitive to the neural activation cues mediating the cellular expression of these proteins.

  16. Inhibitory Activity of Yokukansankachimpihange against Nerve Growth Factor-Induced Neurite Growth in Cultured Rat Dorsal Root Ganglion Neurons.

    Science.gov (United States)

    Murayama, Chiaki; Watanabe, Shimpei; Nakamura, Motokazu; Norimoto, Hisayoshi

    2015-01-01

    Chronic pruritus is a major and distressing symptom of many cutaneous diseases, however, the treatment remains a challenge in the clinic. The traditional Chinese-Japanese medicine (Kampo medicine) is a conservative and increasingly popular approach to treat chronic pruritus for both patients and medical providers. Yokukansankachimpihange (YKH), a Kampo formula has been demonstrated to be effective in the treatment of itching of atopic dermatitis in Japan although its pharmacological mechanism is unknown clearly. In an attempt to clarify its pharmacological actions, in this study, we focused on the inhibitory activity of YKH against neurite growth induced with nerve growth factor (NGF) in cultured rat dorsal root ganglion (DRG) neurons because epidermal hyperinnervation is deeply related to itch sensitization. YKH showed approximately 200-fold inhibitory activity against NGF-induced neurite growth than that of neurotropin (positive control), a drug used clinically for treatment of chronic pruritus. Moreover, it also found that Uncaria hook, Bupleurum root and their chemical constituents rhynchophylline, hirsutine, and saikosaponin a, d showed inhibitory activities against NGF-induced neurite growth, suggesting they should mainly contribute to the inhibitory activity of YKH. Further study on the effects of YKH against epidermal nerve density in "itch-scratch" animal models is under investigation. PMID:26287150

  17. Nerve growth factor injected into the gastric ulcer base incorporates into endothelial, neuronal, glial and epithelial cells: implications for angiogenesis, mucosal regeneration and ulcer healing.

    Science.gov (United States)

    Tanigawa, T; Ahluwalia, A; Watanabe, T; Arakawa, T; Tarnawski, A S

    2015-08-01

    A previous study has demonstrated that locally administered growth factors such as epidermal growth factor, basic fibroblast growth factor and hepatocyte growth factor can accelerate healing of experimental gastric ulcers in rats. That study indicates that locally administered growth factors can exert potent biological effects resulting in enhanced gastric ulcers healing. However, the fate of injected growth factors, their retention and localization to specific cellular compartments have not been examined. In our preliminary study, we demonstrated that local injection of nerve growth factor to the base of experimental gastric ulcers dramatically accelerates ulcer healing, increases angiogenesis - new blood vessel formation, and improves the quality of vascular and epithelial regeneration. Before embarking on larger, definitive and time sequence studies, we wished to determine whether locally injected nerve growth factor is retained in gastric ulcer's tissues and taken up by specific cells during gastric ulcer healing. Gastric ulcers were induced in anesthetized rats by local application of acetic acid using standard methods; and, 60 min later fluorescein isothiocyanate-labeled nerve growth factor was injected locally to the ulcer base. Rats were euthanized 2, 5 and 10 days later. Gastric specimens were obtained and processed for histology. Unstained paraffin sections were examined under a fluorescence microscope, and the incorporation of fluorescein isothiocyanate-labeled nerve growth factor into various gastric tissue cells was determined and quantified. In addition, we performed immunostaining for S100β protein that is expressed in neural components. Five and ten days after ulcer induction labeled nerve growth factor (injected to the gastric ulcer base) was incorporated into endothelial cells of blood vessels, neuronal, glial and epithelial cells, myofibroblasts and muscle cells. This study demonstrates for the first time that during gastric ulcer healing

  18. Image features of two rare mediastinal tumors: schwannoma of intrathoracic phrenic nerve and clear cell chondrosarcoma of the rib

    Institute of Scientific and Technical Information of China (English)

    Ting-Kai Leung; Chien-Jui Cheng; Chi-Ming Lee; Li-Kuo Shen; Hung-Jung Wang; Ya-Yen Chen

    2005-01-01

    @@ The current report focuses on two patients of the same age who presented similar appearances on initial anteroposterior chest images. Follow-up images showed superoanterior and superoposterior mediastinal lesions. The first patient with noninvasive cystic thymoma was suspected before surgery, while the pathologic diagnosis was intrathoracic phrenic nerve schwannoma. The second patient was with an asymmetric, dumbbell-shaped paravertebral tumor over T3 and T4 on the left side. The preoperative diagnostic images were interpreted as showing a neurogenic tumor. However, the pathologic report was cell chondrosarcoma.

  19. Use of hybrid chitosan membranes and human mesenchymal stem cells from the Wharton jelly of umbilical cord for promoting nerve regeneration in an axonotmesis rat model

    Institute of Scientific and Technical Information of China (English)

    Andrea G(a)rtner; Yuri Nakamura; Satoshi Hayakawa; Akiyoshi Osakah; Beatriz Porto; Ana Lúcia Luís; Artur SP Varej(a)o; Ana Colette Maurício; Tiago Pereira; Maria Jo(a)o Sim(o)es; Paulo AS Armada-da-Silva; Miguel L Fran(c)a; Rosa Sousa; Simone Bompasso; Stefania Raimondo; Yuki Shirosaki

    2012-01-01

    Many studies have been dedicated to the development of scaffolds for improving post-traumatic nerve regeneration.The goal of this study was to assess the effect on nerve regeneration,associating a hybrid chitosan membrane with non-differentiated human mesenchymal stem cells isolated from Wharton's jelly of umbilical cord,in peripheral nerve reconstruction after crush injury.Chromosome analysis on human mesenchymal stem cell line from Wharton's jelly was carried out and no structural alterations were found in metaphase.Chitosan membranes were previously tested in vitro,to assess their ability in supporting human mesenchymal stem cell survival,expansion,and differentiation.For the in vivo testing,Sasco Sprague adult rats were divided in 4 groups of 6 or 7 animals each:Group 1,sciatic axonotmesis injury without any other intervention (Group 1-Crush); Group 2,the axonotmesis lesion of 3 mm was infiltrated with a suspension of 1 250- 1 500 human mesenchymal stem cells (total volume of 50 μL) (Group 2-CrushCell); Group 3,axonotmesis lesion of 3 mm was enwrapped with a chitosan type Ⅲ membrane covered with a monolayer of non-differentiated human mesenchymal stem cells (Group 3-CrushChitlllCell) and Group 4,axonotmesis lesion of 3 mm was enwrapped with a chitosan type Ⅲ membrane (Group 4-CrushChitlll).Motor and sensory functional recovery was evaluated throughout a healing period of 12 weeks using sciatic functional index,static sciatic index,extensor postural thrust,and withdrawal reflex latency.Stereological analysis was carried out on regenerated nerve fibers.Results showed that infiltration of human mesenchymal stem cells,or the combination of chitosan membrane enwrapment and human mesenchymal stem cell enrichment after nerve crush injury provide a slight advantage to post-traumatic nerve regeneration.Results obtained with chitosan type Ⅲ membrane alone confirmed that they significantly improve post-traumatic axonal regrowth and may represent a very promising

  20. Solid state theory of competitive diffusion of associated Na+ and K+ in cells by free cation and vacancy (hole) mechanisms, with application to nerve.

    Science.gov (United States)

    Cope, F W

    1977-01-01

    If, as recent evidence indicates, most cell potassium is associated with macromolecular fixed charge, then diffusion of potassium ions in cells might occur by (1) diffusion of the small fraction of free potassium in cell water (analogous to electrons in the conduction band of a semiconductor) or by (2) diffusion of vacancies on association sites (analogous to holes in a semiconductor). Derivations of the Fick first law of diffusion predict that partial substitution of sodium for potassium in the cell produces opposite effects on the effective diffusion constant of potassium for those mechanisms. Application of that substitution to nerve data suggests that rubidium ions diffuse by a free cation result when the nerve is clamped at its resting potential, but by a vacancy mechanism when the nerve is clamped at zero voltage. PMID:613332

  1. Motion sickness is associated with an increase in vestibular modulation of skin but not muscle sympathetic nerve activity.

    Science.gov (United States)

    Klingberg, Danielle; Hammam, Elie; Macefield, Vaughan G

    2015-08-01

    We have previously shown that sinusoidal galvanic vestibular stimulation (sGVS), delivered bilaterally at frequencies of 0.08-2.00 Hz, causes a pronounced modulation of muscle sympathetic nerve activity (MSNA) and skin sympathetic nerve activity (SSNA), together with robust frequency-dependent illusions of side-to-side motion. At low frequencies of sGVS (≤0.2 Hz), some subjects report nausea, so we tested the hypothesis that vestibular modulation of MSNA and SSNA is augmented in individuals reporting nausea. MSNA was recorded via tungsten microelectrodes inserted into the left common peroneal nerve in 22 awake, seated subjects; SSNA was recorded in 14 subjects. Bipolar binaural sGVS (±2 mA, 100 cycles) was applied to the mastoid processes at 0.08, 0.13, and 0.18 Hz. Nausea was reported by 21 out of 36 subjects (58 %), but across frequencies of sGVS there was no difference in the magnitude of the vestibular modulation of MSNA in subjects who reported nausea (27.1 ± 1.8 %) and those who did not (30.4 ± 2.9 %). This contrasts with the significantly greater vestibular modulation of SSNA with nausea (41.1 ± 2.0 vs. 28.7 ± 3.1 %) and indicates an organ-specific modulation of sympathetic outflow via the vestibular system during motion sickness. PMID:26025612

  2. Vagus Nerve through α7 nAChR Modulates Lung Infection and Inflammation: Models, Cells, and Signals

    Directory of Open Access Journals (Sweden)

    Haiya Wu

    2014-01-01

    Full Text Available Cholinergic anti-inflammatory pathway (CAP bridges immune and nervous systems and plays pleiotropic roles in modulating inflammation in animal models by targeting different immune, proinflammatory, epithelial, endothelial, stem, and progenitor cells and signaling pathways. Acute lung injury (ALI is a devastating inflammatory disease. It is pathogenically heterogeneous and involves many cells and signaling pathways. Here, we emphasized the research regarding the modulatory effects of CAP on animal models, cell population, and signaling pathways that involved in the pathogenesis of ALI. By comparing the differential effects of CAP on systemic and pulmonary inflammation, we postulated that a pulmonary parasympathetic inflammatory reflex is formed to sense and respond to pathogens in the lung. Work targeting the formation and function of pulmonary parasympathetic inflammatory reflex would extend our understanding of how vagus nerve senses, recognizes, and fights with pathogens and inflammatory responses.

  3. The effects of functional magnetic nanotubes with incorporated nerve growth factor in neuronal differentiation of PC12 cells

    Energy Technology Data Exchange (ETDEWEB)

    Xie Jining; Chen Linfeng; Varadan, Vijay K [Nanomaterials and Nanotubes Research Laboratory, College of Engineering, University of Arkansas, Fayetteville, AR 72701 (United States); Yancey, Justin; Srivatsan, Malathi [Department of Biological Sciences, Arkansas State University, State University, AR 72467 (United States)], E-mail: jxie@uark.edu, E-mail: msrivatsan@astate.edu

    2008-03-12

    In this in vitro study the efficiency of magnetic nanotubes to bind with nerve growth factor (NGF) and the ability of NGF-incorporated magnetic nanotubes to release the bound NGF are investigated using rat pheochromocytoma cells (PC12 cells). It is found that functional magnetic nanotubes with NGF incorporation enabled the differentiation of PC12 cells into neurons exhibiting growth cones and neurite outgrowth. Microscope observations show that filopodia extending from neuron growth cones were in close proximity to the NGF-incorporated magnetic nanotubes, at times appearing to extend towards or into them. These results show that magnetic nanotubes can be used as a delivery vehicle for NGF and thus may be exploited in attempts to treat neurodegenerative disorders such as Parkinson's disease with neurotrophins. Further neurite outgrowth can be controlled by manipulating magnetic nanotubes with external magnetic fields, thus helping in directed regeneration.

  4. An effective technique for isolating adult activated Schwann cells

    Institute of Scientific and Technical Information of China (English)

    Jifei Zhang; Lianhong Jin; Yuzhen Zhao

    2006-01-01

    BACKGROUND: Schwann cells (SCs) are neuroglial cells of peripheral nerve and play a key role in repairing peripheral nerve injury; therefore, it provides an important evidence for transplantation of SCs which are characterized by active proliferation and adult high-purity in vitro after nerve injury in clinic, and also develops a new therapeutic way for nerve injury.OBJECTIVE: To investigate an effective technique for isolating adult activated Schwann cells.DESIGN: Controlled observational study.SETTING: Mudanjiang Medical College.MATERIALS: The experiment was completed at the Department of Medical Genetics of Harbin Medical University from March 2003 to April 2005. Health female Wistar rats, aged 2 months, weighting 150-160 g, were randomly divided into 3 groups with 5 in each group.METHODS: The right sciatic nerves from 15 Wistar rats were exposed and transected at the mid thigh under pentobarbital anesthesia (4 mg/kg, I.p). Seven days later, the distal segments of the predegenerated nerves were removed and used to produce adult Schwann cell cultures. The distal segment of the predegenerated nerve, 20 mm in length, was resected. The nerve was cut into pieces 1 mm in length and incubated for 3 hours under CO2 at 37 ℃ with an enzyme mixture of 0.05% collagenase/dispase. Rats were divided into 3 groups:① Group 1: The nerve fragments were explanted in poly-L-lysine and laminin-coated dishes with BS medium from the 1st to the 6th day. On the 6th day, the fragments were removed into a new poly-L-lysine-laminin-coated dish and the BS medium was changed to BS with 10% FBS. The nerve fragments were replaced repeatedly in the same way in new dishes on the 12th and the 18th days. ②Group 2: For the first 3 days, the nerve fragments were fed with BS with 10% FBS. This medium was changed to BS medium on the third day. The nerve fragments were removed to another dish on day 6 and BS medium was changed to BS with 25 mL/L FBS. Hereafter the culture method was the same as

  5. 骨髓间充质干细胞向神经细胞的分化%Bone marrow mesenchymal stem cells differentiation into nerve cells

    Institute of Scientific and Technical Information of China (English)

    安秀峰; 黄汉昌; 姜招峰

    2013-01-01

    近年来,骨髓间充质干细胞逐渐成为神经科学领域的研究热点,广泛用于治疗神经退行性疾病,其原因是;骨髓间充质干细胞可在诱导物存在下定向分化为有功能的神经元细胞,并能成功表达神经标志蛋白.结合近几年的研究进展,主要从骨髓间充质干细胞的临床试验和应用;激光辐射、氧气含量和神经细胞对骨髓间充质干细胞分化为神经细胞的影响;microRNA、Notch信号通路和Wnt信号通路对骨髓间充质干细胞分化为神经细胞的调节作用等三方面进行阐述.%For the past few years, bone marrow mesenchymal stem cells have gradually become a research focus in the field of neuroscience, and have been widely used in the treatment of neurodegenerative diseases. It is just because that it can differentiate into functional neuron and express neural marker proteins successfully when inducer exists. Combined with the recent research progress, this paper will introduce the bone marrow mesenchymal stem cells from the following three aspects: firstly, the clinical trial and application of bone marrow mesenchymal stem cells; secondly, the effects of laser radiation, oxygen content and the nerve cells on the process of bone marrow mesenchymal stem cells differentiate into nerve cells; thirdly, microRNA, Notch signal pathway and Wnt signal pathway regulate the process of bone marrow mesenchymal stem cells differentiating into nerve cells.

  6. Hypoxia-Induced Upregulation of miR-132 Promotes Schwann Cell Migration After Sciatic Nerve Injury by Targeting PRKAG3.

    Science.gov (United States)

    Yao, Chun; Shi, Xiangxiang; Zhang, Zhanhu; Zhou, Songlin; Qian, Tianmei; Wang, Yaxian; Ding, Fei; Gu, Xiaosong; Yu, Bin

    2016-10-01

    Following peripheral nerve injury, hypoxia is formed as a result of defects in blood supply at the injury site. Despite accumulating evidence on the effects of microRNAs (miRNAs) on phenotype modulation of Schwann cells (SCs) after peripheral nerve injury, the impact of hypoxia on SC behaviors through miRNAs during peripheral nerve regeneration has not been estimated. In this study, we confirmed our previous microarray data on the upregulation of miR-132 after sciatic nerve injury in rats and observed that overexpression of miR-132 significantly promoted cell migration of primary cultured SCs. Interestingly, hypoxia-increased expression of miR-132 also enhanced SC migration while inhibition of miR-132 suppressed hypoxia-induced increase in SC migration. miR-132 downregulated PRKAG3 through binding to its 3'-UTR, and PRKAG3 knockdown compromised the reducing effect of miR-132 inhibition on SC migration under normal or hypoxia condition. Moreover, in vivo injection of miR-132 agomir into rats with sciatic nerve transection accelerated SC migration from the proximal to distal stump. Overall, our results suggest that the hypoxia-induced upregulation of miR-132 could promote SC migration and facilitate peripheral nerve regeneration.

  7. Relation of Na+, K(+)-ATPase to delayed motor nerve conduction velocity: effect of aldose reductase inhibitor, ADN-138, on Na+, K(+)-ATPase activity.

    Science.gov (United States)

    Hirata, Y; Okada, K

    1990-06-01

    The role of sorbitol, myo-inositol, and Na+, K(+)-adenosine triphosphatase (ATPase) activity on motor nerve conduction velocity (MNCV) in streptozotocin (STZ)-diabetic rats was studied. Reduction of MNCV and Na+, K(+)-ATPase in caudal nerves appeared after 3 weeks of diabetes, and at this time treatment with aldose reductase inhibitor (ARI), ADN-138 and 1% myo-inositol supplement was begun. One percent myo-inositol supplement for 3 weeks resulted in a significant increase in myo-inositol levels in diabetic nerves, but left MNCV and sorbitol levels unchanged. In contrast, treatment with ADN-138 for 3 weeks reduced sorbitol levels in diabetic nerves and resulted in significant increases in MNCV and Na+, K(+)-ATPase in the nerves. Since ADN-138 did not restore myo-inositol levels, the increase in Na+, K(+)-ATPase levels by ADN-138 treatment was independent of myo-inositol levels. Also, nerve Na+ levels in ADN-138-treated rats were reduced and the ratio of K+ to Na+ was raised, while 1% myo-inositol supplement did not affect them. These results suggest that treatment with ADN-138 elevates MNCV through a series of processes: ARI----reduction of sorbitol level----increase in Na+, K(+)-ATPase activity----correction of K+, Na+ imbalance----increase in MNCV.

  8. Effects of lower body positive pressure on muscle sympathetic nerve activity response [correction of respopnse] to head-up tilt.

    Science.gov (United States)

    Fu, Q; Iwase, S; Niimi, Y; Kamiya, A; Kawanokuchi, J; Cui, J; Mano, T

    2001-07-01

    The benefits of lower body positive pressure (LBPP) are generally accepted for clinical treatment in medical emergencies caused by massive bleeding to maintain the systemic blood pressure. They are also used by NASA post spaceflight for preventing orthostatic hypotension in the astronauts. However, controversy still exists concerning the mechanisms underlying LBPP benefits. The purpose of this study was to test the hypothesis that the baroreflex-mediated enhancement in sympathetic activity would be attenuated by LBPP during an orthostatic challenge in humans. Specifically, we studied 1) the sympathetic activity responses by the microneurographic technique, using direct intraneural measurement of muscle sympathetic nerve activity (MSNA); and 2) the contributions of preload and afterload to the chances in MSNA response during orthostasis on application of LBPP. To accomplish these issues, MSNA was recorded microneurographically along with noninvasive measurement of the cardiovascular variables in all the subjects during exposure to a 70 degrees HUT with 30-mm Hg LBPP.

  9. Progesterone and peripheral nerve regeneration

    Institute of Scientific and Technical Information of China (English)

    Fei Fan; Haichao Li; Yuwei Wang; Yanglin Zheng; Lianjun Jia; Zhihui Wang

    2006-01-01

    OBJECTIVE: To explore the effect of progesterone on peripheral nerve regeneration.DATA SOURCES: An online search of Medline and OVID databases was under taken to identify articles about progesterone and peripheral nerve regeneration published in English between January 1990 and June 2004 by using the keywords of "peripheral nerve, injury, progesterone, regeneration".STUDY SELECTION: The data were primarily screened, those correlated with progesterone and peripheral nerve regeneration were involved, and their original articles were further searched, the repetitive studies or reviews were excluded.DATA EXTRACTION: Totally 59 articles about progesterone and peripheral nerve regeneration were collected, and 26 of them were involved, the other 33 excluded ones were the repetitive studies or reviews.DATA SYNTHESIS: Recent researches found that certain amount of progesterone could be synthetized in peripheral nervous system, and the expression of progesterone receptor could be found in sensory neurons and Schwann cells. After combined with the receptor, endogenous and exogenous progesterone can accelerate the formation of peripheral nerve myelin sheath, also promote the axonal regeneration.CONCLUSION: Progesterone plays a role in protecting neurons, increasing the sensitivity of nerve tissue to nerve growth factor, and accelerating regeneration of nerve in peripheral nerve regeneration, which provides theoretical references for the treatment of demyelinated disease and nerve injury, as well as the prevention of neuroma, especially that the in vivo level of progesterone should be considered for the elderly people accompanied by neuropathy and patients with congenital luteal phase defect, which is of positive significance in guiding the treatment.

  10. Effects of huperzine A on secretion of nerve growth factor in cultured rat cortical astrocytes and neurite outgrowth in rat PC12 cells

    Institute of Scientific and Technical Information of China (English)

    Li-li TANG; Rui WANG; Xi-can TANG

    2005-01-01

    Aim: To study the effects of huperzine A (HupA) on neuritogenic activity and the expression of nerve growth factor (NGF). Methods: After being treated with 10 μmol/L HupA, neurite outgrowth of PC12 cells was observed and counted under phase-contrast microscopy. Mitogenic activity was assayed by [3H]thymidine incorporation. Cell cytotoxicity was evaluated by lactate dehydrogenase (LDH)release. AChE activity, mRNA and protein expression were measured by the Ellman's method, RT-PCR, and Western blot, respectively. NGF mRNA and protein levels were determined by RT-PCR and ELISA assays. Results: Treatment of PC 12 cells with 10 μmol/L HupA for 48 h markedly increased the number of neuritebearing cells, but caused no significant alteration in cell viability or other signs of cytotoxicity. In addition to inhibiting AChE activity, 10 μmol/L HupA also increased the mRNA and protein levels of this enzyme. In addition, following 2 h exposure of the astrocytes to 10 μmol/L HupA, there was a significant up-regulation of mRNA for NGF and P75 low-affinity NGF receptor. The protein level of NGF was also increased after 24 h treatment with HupA. Conclusion: Our findings demonstrate for the first time that HupA has a direct or indirect neurotrophic activity, which might be beneficial in treatment of neurodegenerative disorders such as Alzheimer disease.

  11. Neurogenesis in an early protostome relative: progenitor cells in the ventral nerve center of chaetognath hatchlings are arranged in a highly organized geometrical pattern.

    Science.gov (United States)

    Perez, Yvan; Rieger, Verena; Martin, Elise; Müller, Carsten H G; Harzsch, Steffen

    2013-05-01

    Emerging evidence suggests that Chaetognatha represent an evolutionary lineage that is the sister group to all other Protostomia thus promoting these animals as a pivotal model for our understanding of bilaterian evolutionary history. We have analyzed the proliferation of neuronal progenitor cells in the developing ventral nerve center (VNC) of Spadella cephaloptera hatchlings. To that end, for the first time in Chaetognatha, we performed in vivo incorporation experiments with the S-phase specific mitosis marker bromodeoxyuridine (BrdU). Our experiments provide evidence for a high level of mitotic activity in the VNC for ca. 3 days after hatching. Neurogenesis is carried by presumptive neuronal progenitor cells that cycle rapidly and most likely divide asymmetrically. These progenitors are arranged in a distinct grid-like geometrical pattern including about 35 transverse rows. Considering Chaetognaths to be an early offshoot of the protostome lineage we conclude that the presence of neuronal progenitor cells with asymmetric division seems to be a feature that is rooted deeply in the Metazoa. In the light of previous evidence indicating the presence of serially iterated peptidergic neurons with individual identities in the chaetognath VNC, we discuss if these neuronal progenitor cells give rise to distinct lineages. Furthermore, we evaluate the serially iterated arrangement of the progenitor cells in the light of evolution of segmentation. PMID:23483730

  12. Ammodytoxin, a neurotoxic secreted phospholipase A2, can act in the cytosol of the nerve cell

    International Nuclear Information System (INIS)

    Recent identification of intracellular proteins that bind ammodytoxin (calmodulin, 14-3-3 proteins, and R25) suggests that this snake venom presynaptically active phospholipase A2 acts intracellularly. As these ammodytoxin acceptors are cytosolic and mitochondrial proteins, the toxin should be able to enter the cytosol of a target cell and remain stable there to interact with them. Using laser scanning confocal microscopy we show here that Alexa-labelled ammodytoxin entered the cytoplasm of the rat hippocampal neuron and subsequently also its nucleus. The transport of proteins into the nucleus proceeds via the cytosol of a cell, therefore, ammodytoxin passed the cytosol of the neuron on its way to the nucleus. Although it is not yet clear how ammodytoxin is translocated into the cytosol of the neuron, our results demonstrate that its stability in the cytosol is not in question, providing the evidence that the toxin can act in this cellular compartment

  13. Augmented activity of the pelvic nerve afferent mediated by TRP channels in dextran sulfate sodium (DSS)-induced colitis of rats.

    Science.gov (United States)

    Makimura, Yukitoshi; Ito, Koichi; Kuwahara, Masayoshi; Tsubone, Hirokazu

    2012-08-01

    Enteritis has been recognized as a major symptom in domestic animals and human patients suffering from feed and food poisonings. The aim of the present study was to clarify the excitatory mechanism of the pelvic nerve afferent which may influence the occurrence of enteritis in response to nociceptive chemical stimuli of the colon in normal and abnormal rats with colitis induced by dextran sulfate sodium (DSS). The pelvic nerve afferent activity was markedly increased by colonic instillation of solution (0.5 ml) of acetic acid (5-25%) and capsaicin (100 μg/ml). The nerve activity was augmented by colonic instillation of capsaicin to a greater extent in rats with DSS-induced colitis than in normal control rats. This augmented activity by capsaicin was more prominent at one day (DSS-1) than at 8 day (DSS-8) after the administration of DSS. The increased nerve activity caused by capsaicin in DSS-1 and DSS-8 was significantly inhibited by pretreatment with ruthenium red, which is a nonselective inhibitor of TRP channels of unmyelinated C-fibers (nociceptors). In conclusion, it was elucidated that the nociceptive function of the pelvic nerve was largely elevated at one day after DSS-induced colitis and such increased function was mostly mediated by TRP channels.

  14. Loss of Ab-nerve endings associated with the Merkel cell-neurite complex in the lesional oral mucosa epithelium of lichen planus and hyperkeratosis

    Institute of Scientific and Technical Information of China (English)

    Daniela Caldero n Carrio n; Yu ksel Korkmaz; Britta Cho; Marion Kopp; Wilhelm Bloch; Klaus Addicks; Wilhelm Niedermeier

    2016-01-01

    The Merkel cell-neurite complex initiates the perception of touch and mediates Ab slowly adapting type I responses. Lichen planus is a chronic inflammatory autoimmune disease with T-cell-mediated inflammation, whereas hyperkeratosis is characterized with or without epithelial dysplasia in the oral mucosa. To determine the effects of lichen planus and hyperkeratosis on the Merkel cell-neurite complex, healthy oral mucosal epithelium and lesional oral mucosal epithelium of lichen planus and hyperkeratosis patients were stained by immunohistochemistry (the avidin-biotin-peroxidase complex and double immunofluorescence methods) using pan cytokeratin, 20 (K20, a Merkel cell marker), and neurofilament 200 (NF200, a myelinated Ab- and Ad-nerve fibre marker) antibodies. NF200-immunoreactive (ir) nerve fibres in healthy tissues and in the lesional oralmucosa epitheliumof lichen planus and hyperkeratosis were counted and statistically analysed. In the healthy oral mucosa, K20-positive Merkel cells with and without close association to the intraepithelial NF200-ir nerve fibres were detected. In the lesional oral mucosa of lichen planus and hyperkeratosis patients, extremely rare NF200-ir nerve fibres were detected only in the lamina propria. Compared with healthy tissues, lichen planus and hyperkeratosis tissues had significantly decreased numbers of NF200-ir nerve fibres in the oral mucosal epithelium. Lichen planus and hyperkeratosis were associated with the absence of Ab-nerve endings in the oral mucosal epithelium. Thus, we conclude that mechanosensation mediated by the Merkel cell-neurite complex in the oral mucosal epithelium is impaired in lichen planus and hyperkeratosis.

  15. Characteristic element of matrix attachment region mediates vector attachment and enhances nerve growth factor expression in Chinese hamster ovary cells.

    Science.gov (United States)

    Wang, X Y; Zhang, J H; Sun, Q L; Yao, Z Y; Deng, B G; Guo, W Y; Wang, L; Dong, W H; Wang, F; Zhao, C P; Wang, T Y

    2015-01-01

    Preliminary studies have suggested that a characteristic element of the matrix attachment region (MAR) in human interferon-β mediates the adhesion of vectors to Chinese hamster ovary (CHO) cells. In this study, we investigated if vector adhesion increased nerve growth factor (NGF) expression in CHO cells. The MAR characteristic element sequence of human interferon-β was inserted into the multiple-cloning site of the pEGFP-C1 vector. The target NGF gene was inserted upstream of the MAR characteristic element sequence to construct the MAR/NGF expression vector. The recombinant plasmid was transfected into CHO cells and stable monoclonal cells were selected using G418. NGF mRNA and protein expression was detected by reverse transcriptase-polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. Plasmid reduction experiments were used to determine the state of transfected plasmid in mammalian cells. The insertion of MAR into the vector increased NGF expression levels in CHO cells (1.93- fold) compared to the control. The recombinant plasmid expressing the MAR sequence was digested into a linear space vector. The inserted MAR and NGF sequences were consistent with those inserted into the plasmid before recombination. Therefore, we concluded that the MAR characteristic element mediates vector adhesion to CHO cells and enhances the stability and efficiency of the target gene expression. PMID:26345852

  16. Comparison of Central Corneal Thickness and Retinal Nerve Fiber Layer Thickness and Ganglion Cell Complex in Patients with Ocular Hypertension

    Directory of Open Access Journals (Sweden)

    Gamze Mumcu Taşlı

    2013-12-01

    Full Text Available Purpose: To evaluate the correlation of retinal nerve fiber layer thickness (RNFLT with ganglion cell complex and central corneal thickness (CCT measurements in patients with ocular hypertension and healthy subjects. Material and Method: Seventy-six eyes of 38 patients with ocular hypertension and 76 eyes of 38 healthy subjects were included in this study. Both groups were stratified by CCT into 579 µm (p0.05. In the control group, there was no significant correlation between CCT and RNFLT (average, superior average, inferior average measurements (p>0.05. There was no significant correlation between CCT and average, superior average, inferior average ganglion cell complex in both groups. Discussion: Ocular hypertension patients with CCT <550 µm may represent patients who have very early undetected glaucoma. This may in part explain the higher risk of these patients for progression to glaucoma. (Turk J Ophthalmol 2013; 43: 385-90

  17. A NEW MODEL AND IMPROVED CABLE FUNCTION FOR REPRESENTING THE ACTIVATING PERIPHERAL NERVES BY A TRANSVERSE ELECTRIC FIELD DURING MAGNETIC STIMULATION

    Institute of Scientific and Technical Information of China (English)

    Yu Hui; Zheng Chongxun; Wang Haiyan; Wang Yi

    2005-01-01

    Objective Previous studies of peripheral nerves activation during magnetic stimulation have focused almost exclusively on the cause of high external parallel electric field along the nerves, whereas the effect of the transverse component has been ignored. In the present paper, the classical cable function is modified to represent the excitation of peripheral nerves stimulated by a transverse electric field during magnetic stimulation. Methods Responses of the Ranvier nodes to a transverse-field are thoroughly investigated by mathematic simulation. Results The simulation demonstrates that the excitation results from the net inward current driven by an external field. Based on a two-stage process, a novel model is introduced to describe peripheral nerves stimulated by a transverse-field. Based on the new model, the classical cable function is modified. Conclusion Using this modified cable equation, the excitation threshold of peripheral nerves in a transverse field during MS is obtained. The modified cable equation can be used to represent the response of peripheral nerves by an arbitrary electric field.

  18. Activation of Growth-associated Protein by Intragastric Brazilein in Motor Neuron of Spinal Cord Connected with Injured Sciatic Nerve in Mice

    Institute of Scientific and Technical Information of China (English)

    CAO Jian; LI Li-sen; LIU Biao; LIU Hao-yu; ZHANG Hui; ZHAO Ming-ming; YIN Wei-tian

    2011-01-01

    The purpose of this study is to explore the expression of growth-associated protein(GAP-43) in spinal cord segments connected with injured sciatic nerve by the treatment with brazilein in mice. Unilateral sciatic nerve interruption and anastomosis were performed. Physiological saline(blank group), high dose, middle dose and low dose of brazilein were administrated intragastrically to healthy adult BALB/c mice in separate groups. L4-6 spinal segments connected with the sciatic nerve were harvested. Real-time PCR(Polymerase chain reaction) and Western blot analysis were performed to detect the expression of GAP-43 in spinal segments. Histological staining on myelin and the electrophysiology were performed to examine the sciatic nerve recovery. GAP-43 was activated in spinal cord L4-6 connected with injured sciatic nerve. In the survival time of 12 h, 24 h, 3 d, 5 d, 7 d and 14 d, GAP-43 expression in the motor neurons of spinal cord of the high dose group and that in the middle dose group were significantly higher than those on the low dose and blank groups. Myelin in the high dose group and that in the middle dose group were more mature and the potential amplitude and MNCV(motor nerve conduction velocity) in the high and middle dose groups were obviously higher than those in the low dose group and blank group. Brazilein facilitates the expression of GAP-43 in neurons in spinal cord L4-6 segments connected with injured sciatic nerve, which promotes nerve regeneration.

  19. Activation of p90 Rsk1 is sufficient for differentiation of PC12 cells

    DEFF Research Database (Denmark)

    Silverman, Eran; Frödin, Morten; Gammeltoft, Steen;

    2004-01-01

    We investigated the role of Rsk proteins in the nerve growth factor (NGF) signaling pathway in PC12 cells. When rat Rsk1 or murine Rsk2 proteins were transiently expressed, NGF treatment (100 ng/ml for 3 days) caused three- and fivefold increases in Rsk1 and Rsk2 activities, respectively. Increas...

  20. Differential gene expression in proximal and distal nerve segments of rats with sciatic nerve injury during Wallerian degeneration

    Institute of Scientific and Technical Information of China (English)

    Nan Jiang; Huaiqin Li; Yi Sun; Dexin Yin; Qin Zhao; Shusen Cui; Dengbing Yao

    2014-01-01

    Wallerian degeneration is a subject of major interest in neuroscience. A large number of genes are differentially regulated during the distinct stages of Wallerian degeneration: transcription factor activation, immune response, myelin cell differentiation and dedifferentiation. Although gene expression responses in the distal segment of the sciatic nerve after peripheral nerve injury are known, differences in gene expression between the proximal and distal segments remain unclear. In the present study in rats, we used microarrays to analyze changes in gene expression, biological processes and signaling pathways in the proximal and distal segments of sciatic nerves under-going Wallerian degeneration. More than 6,000 genes were differentially expressed and 20 types of expression tendencies were identiifed, mainly between proximal and distal segments at 7-14 days after injury. The differentially expressed genes were those involved in cell differentiation, cytokinesis, neuron differentiation, nerve development and axon regeneration. Furthermore, 11 biological processes were represented, related to responses to stimuli, cell apoptosis, inlfammato-ry response, immune response, signal transduction, protein kinase activity, and cell proliferation. Using real-time quantitative PCR, western blot analysis and immunohistochemistry, microarray data were veriifed for four genes: aquaporin-4, interleukin 1 receptor-like 1, matrix metallopro-teinase-12 and periaxin. Our study identiifes differential gene expression in the proximal and distal segments of a nerve during Wallerian degeneration, analyzes dynamic biological changes of these genes, and provides a useful platform for the detailed study of nerve injury and repair during Wallerian degeneration.

  1. Increased encapsulated cell biodelivery of nerve growth factor in the brain by transposon-mediated gene transfer.

    Science.gov (United States)

    Fjord-Larsen, L; Kusk, P; Emerich, D F; Thanos, C; Torp, M; Bintz, B; Tornøe, J; Johnsen, A H; Wahlberg, L U

    2012-10-01

    Nerve growth factor (NGF) is a potential therapeutic agent for Alzheimer's disease (AD) as it has positive effects on the basal forebrain cholinergic neurons whose degeneration correlates with the cognitive decline in AD. We have previously described an encapsulated cell biodelivery device, NsG0202, capable of local delivery of NGF by a genetically modified human cell line, NGC-0295. The NsG0202 devices have shown promising safety and therapeutic results in a small phase 1b clinical study. However, results also show that the NGF dose could advantageously be increased. We have used the sleeping beauty transposon expression technology to establish a new clinical grade cell line, NGC0211, with at least 10 times higher NGF production than that of NGC-0295. To test whether encapsulation of this cell line provides a relevant dose escalation step in delivering NGF for treatment of the cognitive decline in AD patients, we have validated the bioactivity of devices with NGC0211 and NGC-0295 cells in normal rat striatum as well as in the quinolinic acid striatal lesion model. These preclinical animal studies show that implantation of devices with NGC0211 cells lead to significantly higher NGF output, which in both cases correlate with highly improved potency.

  2. Hierarchical structural health monitoring system combining a fiber optic spinal cord network and distributed nerve cell devices

    Science.gov (United States)

    Minakuchi, Shu; Tsukamoto, Haruka; Takeda, Nobuo

    2009-03-01

    This study proposes novel hierarchical sensing concept for detecting damages in composite structures. In the hierarchical system, numerous three-dimensionally structured sensor devices are distributed throughout the whole structural area and connected with the optical fiber network through transducing mechanisms. The distributed "sensory nerve cell" devices detect the damage, and the fiber optic "spinal cord" network gathers damage signals and transmits the information to a measuring instrument. This study began by discussing the basic concept of the hierarchical sensing system thorough comparison with existing fiber optic based systems and nerve systems in the animal kingdom. Then, in order to validate the proposed sensing concept, impact damage detection system for the composite structure was proposed. The sensor devices were developed based on Comparative Vacuum Monitoring (CVM) system and the Brillouin based distributed strain sensing was utilized to gather the damage signals from the distributed devices. Finally a verification test was conducted using prototype devices. Occurrence of barely visible impact damage was successfully detected and it was clearly indicated that the hierarchical system has better repairability, higher robustness, and wider monitorable area compared to existing systems utilizing embedded optical fiber sensors.

  3. Secretion of nerve growth factor, brain-derived neurotrophic factor, and glial cell-line derived neurotrophic factor in co-culture of four cell types in cerebrospinal fluid-containing medium

    Institute of Scientific and Technical Information of China (English)

    Sanjiang Feng; Minghua Zhuang; Rui Wu

    2012-01-01

    The present study co-cultured human embryonic olfactory ensheathing cells, human Schwann cells, human amniotic epithelial cells and human vascular endothelial cells in complete culture medium- containing cerebrospinal fluid. Enzyme linked immunosorbent assay was used to detect nerve growth factor, brain-derived neurotrophic factor, and glial cell line-derived neurotrophic factor secretion in the supernatant of co-cultured cells. Results showed that the number of all cell types reached a peak at 7–10 days, and the expression of nerve growth factor, brain-derived neurotrophic factor, and glial cell line-derived neurotrophic factor peaked at 9 days. Levels of secreted nerve growth factor were four-fold higher than brain-derived neurotrophic factor, which was three-fold higher than glial cell line-derived neurotrophic factor. Increasing concentrations of cerebrospinal fluid (10%, 20% and 30%) in the growth medium caused a decrease of neurotrophic factor secretion. Results indicated co-culture of human embryonic olfactory ensheathing cells, human Schwann cells, human amniotic epithelial cells and human vascular endothelial cells improved the expression of nerve growth factor, brain-derived neurotrophic factor, and glial cell line-derived neurotrophic factor. The reduction of cerebrospinal fluid extravasation at the transplant site after spinal cord injury is beneficial for the survival and secretion of neurotrophic factors from transplanted cells.

  4. Mechanism of sphingosine 1-phosphate- and lysophosphatidic Acid-induced up-regulation of adhesion molecules and eosinophil chemoattractant in nerve cells.

    LENUS (Irish Health Repository)

    Costello, Richard W

    2011-05-01

    The lysophospholipids sphingosine 1-phosphate (S1P) and lysophosphatidic acid (LPA) act via G-protein coupled receptors S1P(1-5) and LPA(1-3) respectively, and are implicated in allergy. Eosinophils accumulate at innervating cholinergic nerves in asthma and adhere to nerve cells via intercellular adhesion molecule-1 (ICAM-1). IMR-32 neuroblastoma cells were used as an in vitro cholinergic nerve cell model. The G(i) coupled receptors S1P(1), S1P(3), LPA(1), LPA(2) and LPA(3) were expressed on IMR-32 cells. Both S1P and LPA induced ERK phosphorylation and ERK- and G(i)-dependent up-regulation of ICAM-1 expression, with differing time courses. LPA also induced ERK- and G(i)-dependent up-regulation of the eosinophil chemoattractant, CCL-26. The eosinophil granule protein eosinophil peroxidase (EPO) induced ERK-dependent up-regulation of transcription of S1P(1), LPA(1), LPA(2) and LPA(3), providing the situation whereby eosinophil granule proteins may enhance S1P- and\\/or LPA- induced eosinophil accumulation at nerve cells in allergic conditions.

  5. Mechanism of sphingosine 1-phosphate- and lysophosphatidic Acid-induced up-regulation of adhesion molecules and eosinophil chemoattractant in nerve cells.

    LENUS (Irish Health Repository)

    Costello, Richard W

    2012-02-01

    The lysophospholipids sphingosine 1-phosphate (S1P) and lysophosphatidic acid (LPA) act via G-protein coupled receptors S1P(1-5) and LPA(1-3) respectively, and are implicated in allergy. Eosinophils accumulate at innervating cholinergic nerves in asthma and adhere to nerve cells via intercellular adhesion molecule-1 (ICAM-1). IMR-32 neuroblastoma cells were used as an in vitro cholinergic nerve cell model. The G(i) coupled receptors S1P(1), S1P(3), LPA(1), LPA(2) and LPA(3) were expressed on IMR-32 cells. Both S1P and LPA induced ERK phosphorylation and ERK- and G(i)-dependent up-regulation of ICAM-1 expression, with differing time courses. LPA also induced ERK- and G(i)-dependent up-regulation of the eosinophil chemoattractant, CCL-26. The eosinophil granule protein eosinophil peroxidase (EPO) induced ERK-dependent up-regulation of transcription of S1P(1), LPA(1), LPA(2) and LPA(3), providing the situation whereby eosinophil granule proteins may enhance S1P- and\\/or LPA- induced eosinophil accumulation at nerve cells in allergic conditions.

  6. Regulation of Schwann cell proliferation and migration by miR-1 targeting brain-derived neurotrophic factor after peripheral nerve injury

    Science.gov (United States)

    Yi, Sheng; Yuan, Ying; Chen, Qianqian; Wang, Xinghui; Gong, Leilei; Liu, Jie; Gu, Xiaosong; Li, Shiying

    2016-01-01

    Peripheral nerve injury is a global problem that causes disability and severe socioeconomic burden. Brain-derived neurotrophic factor (BDNF) benefits peripheral nerve regeneration and becomes a promising therapeutic molecule. In the current study, we found that microRNA-1 (miR-1) directly targeted BDNF by binding to its 3′-UTR and caused both mRNA degradation and translation suppression of BDNF. Moreover, miR-1 induced BDNF mRNA degradation primarily through binding to target site 3 rather than target site 1 or 2 of BDNF 3′-UTR. Following rat sciatic nerve injury, a rough inverse correlation was observed between temporal expression profiles of miR-1 and BDNF in the injured nerve. The overexpression or silencing of miR-1 in cultured Schwann cells (SCs) inhibited or enhanced BDNF secretion from the cells, respectively, and also suppressed or promoted SC proliferation and migration, respectively. Interestingly, BDNF knockdown could attenuate the enhancing effect of miR-1 inhibitor on SC proliferation and migration. These findings will contribute to the development of a novel therapeutic strategy for peripheral nerve injury, which overcomes the limitations of direct administration of exogenous BDNF by using miR-1 to regulate endogenous BDNF expression. PMID:27381812

  7. CDNA microarray analysis of nerve growth factor-regulated gene expression profile in rat PC12 cells.

    Science.gov (United States)

    Lee, Kyung-Hee; Ryu, Chun Jeih; Hong, Hyo Jeong; Kim, Jiyoung; Lee, Eunjoo H

    2005-04-01

    Nerve growth factor (NGF)-driven differentiation of PC12 cells into neuronal-like cells provides a representative model system for studying neuronal differentiation processes. Despite of extensive research, gene regulation associated with the differentiation program in PC12 cells still needs to be elucidated. We used cDNA microarray analysis to characterize the response of PC12 cells to NGF at mRNA expression. Forty-six genes were reproducibly influenced by 2-fold or more after NGF treatment for 5 days. Twenty-five of the regulated transcripts were matched to genes which have known functions. Among the microarray results confirmed with real-time reverse transcriptase assay, several genes have not previously known to be modulated by NGF. The results mostly reflected changes in molecules regulating neural plasticity, cytoskeletal organization, and lipid metabolism, which include neuritin, PDZ protein Mrt1, lipoprotein lipase, tropomodulin 1 and rhoB. These observed genetic changes may provide new information about molecular mechanisms underlying NGF-promoted differentiation of PC12 cells. PMID:16076023

  8. Post-embryonic nerve-associated precursors to adult pigment cells: genetic requirements and dynamics of morphogenesis and differentiation.

    Directory of Open Access Journals (Sweden)

    Erine H Budi

    2011-05-01

    Full Text Available The pigment cells of vertebrates serve a variety of functions and generate a stunning variety of patterns. These cells are also implicated in human pathologies including melanoma. Whereas the events of pigment cell development have been studied extensively in the embryo, much less is known about morphogenesis and differentiation of these cells during post-embryonic stages. Previous studies of zebrafish revealed genetically distinct populations of embryonic and adult melanophores, the ectotherm homologue of amniote melanocytes. Here, we use molecular markers, vital labeling, time-lapse imaging, mutational analyses, and transgenesis to identify peripheral nerves as a niche for precursors to adult melanophores that subsequently migrate to the skin to form the adult pigment pattern. We further identify genetic requirements for establishing, maintaining, and recruiting precursors to the adult melanophore lineage and demonstrate novel compensatory behaviors during pattern regulation in mutant backgrounds. Finally, we show that distinct populations of latent precursors having differential regenerative capabilities persist into the adult. These findings provide a foundation for future studies of post-embryonic pigment cell precursors in development, evolution, and neoplasia.

  9. The Evaluation of Nerve Growth Factor Over Expression on Neural Lineage Specific Genes in Human Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Mortazavi Yousef

    2016-07-01

    Full Text Available Objective Treatment and repair of neurodegenerative diseases such as brain tumors, spinal cord injuries, and functional disorders, including Alzheimer’s disease, are challenging problems. A common treatment approach for such disorders involves the use of mesenchymal stem cells (MSCs as an alternative cell source to replace injured cells. However, use of these cells in hosts may potentially cause adverse outcomes such as tumorigenesis and uncontrolled differentiation. In attempt to generate mesenchymal derived neural cells, we have infected MSCs with recombinant lentiviruses that expressed nerve growth factor (NGF and assessed their neural lineage genes. Materials and Methods In this experimental study, we cloned the NGF gene sequence into a helper dependent lentiviral vector that contained the green fluorescent protein (GFP gene. The recombinant vector was amplified in DH5 bacterial cells. Recombinant viruses were generated in the human embryonic kidney 293 (HEK-293 packaging cell line with the helper vectors and analyzed under fluorescent microscopy. Bone marrow mesenchymal cells were infected by recombinant viruses for three days followed by assessment of neural differentiation. We evaluated expression of NGF through measurement of the NGF protein in culture medium by ELISA; neural specific genes were quantified by real-time polymerase chain reaction (PCR. Results We observed neural morphological changes after three days. Quantitative PCR showed that expressions of NESTIN, glial derived neurotrophic factor (GDNF, glial fibrillary acidic protein (GFAP and Microtubule-associated protein 2 (MAP2 genes increased following induction of NGF overexpression, whereas expressions of endogenous NGF and brain derived neural growth factor (BDNF genes reduced. Conclusion Ectopic expression of NGF can induce neurogenesis in MSCs. Direct injection of MSCs may cause tumorigenesis and an undesirable outcome. Therefore an alternative choice to overcome this

  10. Altered Active Zones, Vesicle Pools, Nerve Terminal Conductivity, and Morphology during Experimental MuSK Myasthenia Gravis

    OpenAIRE

    Patel, Vishwendra; Oh, Anne; Voit, Antanina; Sultatos, Lester G.; Babu, Gopal J.; Wilson, Brenda A.; Ho, Mengfei; McArdle, Joseph J.

    2014-01-01

    Recent studies demonstrate reduced motor-nerve function during autoimmune muscle-specific tyrosine kinase (MuSK) myasthenia gravis (MG). To further understand the basis of motor-nerve dysfunction during MuSK-MG, we immunized female C57/B6 mice with purified rat MuSK ectodomain. Nerve-muscle preparations were dissected and neuromuscular junctions (NMJs) studied electrophysiologically, morphologically, and biochemically. While all mice produced antibodies to MuSK, only 40% developed respiratory...

  11. Vestibular modulation of muscle sympathetic nerve activity by the utricle during sub-perceptual sinusoidal linear acceleration in humans.

    Science.gov (United States)

    Hammam, Elie; Hau, Chui Luen Vera; Wong, Kwok-Shing; Kwok, Kenny; Macefield, Vaughan G

    2014-04-01

    We assessed the capacity for the vestibular utricle to modulate muscle sympathetic nerve activity (MSNA) during sinusoidal linear acceleration at amplitudes extending from imperceptible to clearly perceptible. Subjects (n = 16) were seated in a sealed room, eliminating visual cues, mounted on a linear motor that could deliver peak sinusoidal accelerations of 30 mG in the antero-posterior direction. Subjects sat on a padded chair with their neck and head supported vertically, thereby minimizing somatosensory cues, facing the direction of motion in the anterior direction. Each block of sinusoidal motion was applied at a time unknown to subjects and in a random order of amplitudes (1.25, 2.5, 5, 10, 20 and 30 mG), at a constant frequency of 0.2 Hz. MSNA was recorded via tungsten microelectrodes inserted into muscle fascicles of the common peroneal nerve. Subjects used a linear potentiometer aligned to the axis of motion to indicate any perceived movement, which was compared with the accelerometer signal of actual room movement. On average, 67% correct detection of movement did not occur until 6.5 mG, with correct knowledge of the direction of movement at ~10 mG. Cross-correlation analysis revealed potent sinusoidal modulation of MSNA even at accelerations subjects could not perceive (1.25-5 mG). The modulation index showed a positive linear increase with acceleration amplitude, such that the modulation was significantly higher (25.3 ± 3.7%) at 30 mG than at 1.25 mG (15.5 ± 1.2%). We conclude that selective activation of the vestibular utricle causes a pronounced modulation of MSNA, even at levels well below perceptual threshold, and provides further evidence in support of the importance of vestibulosympathetic reflexes in human cardiovascular control. PMID:24504198

  12. Cbl negatively regulates JNK activation and cell death

    Institute of Scientific and Technical Information of China (English)

    Andrew A Sproul; Zhiheng Xu; Michael Wilhelm; Stephen Gire; Lloyd A Greene

    2009-01-01

    Here, we explore the role of Cbl proteins in regulation of neuronal apoptosis. In two paradigms of neuron apopto-sis--nerve growth factor (NGF) deprivation and DNA damage--cellular levels of c-Cbl and Cbl-b fell well before the onset of cell death. NGF deprivation also induced rapid loss of tyrosine phosphorylation (and most likely, activa-tion) of c-Cbl. Targeting e-Cbl and Cbl-b with siRNAs to mimic their loss/inactivation sensitized neuronal cells to death promoted by NGF deprivation or DNA damage. One potential mechanism by which Cbl proteins might affect neuronal death is by regulation of apoptotic c-Jun N-terminal kinase (JNK) signaling. We demonstrate that Cbl pro-teins interact with the JNK pathway components mixed lineage kinase (MLK) 3 and POSH and that knockdown of Cbl proteins is sufficient to increase JNK pathway activity. Furthermore, expression of c-Cbl blocks the ability of MLKs to signal to downstream components of the kinase cascade leading to JNK activation and protects neuronal cells from death induced by MLKs, but not from downstream JNK activators. On the basis of these findings, we propose that Cbls suppress cell death in healthy neurons at least in part by inhibiting the ability of MLKs to activate JNK signaling. Apoptotic stimuli lead to loss of Cbl protein/activity, thereby removing a critical brake on JNK acti-vation and on cell death.

  13. A distal Schwann cell-specific enhancer mediates axonal regulation of the Oct-6 transcription factor during peripheral nerve development and regeneration.

    NARCIS (Netherlands)

    W.J. Mandemakers (Wim); R. Zwart (Ronald); M.M. Jaegle (Martine); E.T. Walbeehm (Erik); P. Visser (Pim); F.G. Grosveld (Frank); D. Meijer (Daniëlle)

    2000-01-01

    textabstractThe POU domain transcription factor Oct-6 is a major regulator of Schwann cell differentiation and myelination. During nerve development and regeneration, expression of Oct-6 is under the control of axonal signals. Identification of the cis-acting elements n

  14. Regulation of Axolotl (Ambystoma mexicanum) Limb Blastema Cell Proliferation by Nerves and BMP2 in Organotypic Slice Culture.

    Science.gov (United States)

    Lehrberg, Jeffrey; Gardiner, David M

    2015-01-01

    We have modified and optimized the technique of organotypic slice culture in order to study the mechanisms regulating growth and pattern formation in regenerating axolotl limb blastemas. Blastema cells maintain many of the behaviors that are characteristic of blastemas in vivo when cultured as slices in vitro, including rates of proliferation that are comparable to what has been reported in vivo. Because the blastema slices can be cultured in basal medium without fetal bovine serum, it was possible to test the response of blastema cells to signaling molecules present in serum, as well as those produced by nerves. We also were able to investigate the response of blastema cells to experimentally regulated changes in BMP signaling. Blastema cells responded to all of these signals by increasing the rate of proliferation and the level of expression of the blastema marker gene, Prrx-1. The organotypic slice culture model provides the opportunity to identify and characterize the spatial and temporal co-regulation of pathways in order to induce and enhance a regenerative response. PMID:25923915

  15. Bridging the gap between postembryonic cell lineages and identified embryonic neuroblasts in the ventral nerve cord of Drosophila melanogaster

    Directory of Open Access Journals (Sweden)

    Oliver Birkholz

    2015-03-01

    Full Text Available The clarification of complete cell lineages, which are produced by specific stem cells, is fundamental for understanding mechanisms, controlling the generation of cell diversity and patterning in an emerging tissue. In the developing Central Nervous System (CNS of Drosophila, neural stem cells (neuroblasts exhibit two periods of proliferation: During embryogenesis they produce primary lineages, which form the larval CNS. After a phase of mitotic quiescence, a subpopulation of them resumes proliferation in the larva to give rise to secondary lineages that build up the CNS of the adult fly. Within the ventral nerve cord (VNC detailed descriptions exist for both primary and secondary lineages. However, while primary lineages have been linked to identified neuroblasts, the assignment of secondary lineages has so far been hampered by technical limitations. Therefore, primary and secondary neural lineages co-existed as isolated model systems. Here we provide the missing link between the two systems for all lineages in the thoracic and abdominal neuromeres. Using the Flybow technique, embryonic neuroblasts were identified by their characteristic and unique lineages in the living embryo and their further development was traced into the late larval stage. This comprehensive analysis provides the first complete view of which embryonic neuroblasts are postembryonically reactivated along the anterior/posterior-axis of the VNC, and reveals the relationship between projection patterns of primary and secondary sublineages.

  16. Regulation of Axolotl (Ambystoma mexicanum) Limb Blastema Cell Proliferation by Nerves and BMP2 in Organotypic Slice Culture.

    Science.gov (United States)

    Lehrberg, Jeffrey; Gardiner, David M

    2015-01-01

    We have modified and optimized the technique of organotypic slice culture in order to study the mechanisms regulating growth and pattern formation in regenerating axolotl limb blastemas. Blastema cells maintain many of the behaviors that are characteristic of blastemas in vivo when cultured as slices in vitro, including rates of proliferation that are comparable to what has been reported in vivo. Because the blastema slices can be cultured in basal medium without fetal bovine serum, it was possible to test the response of blastema cells to signaling molecules present in serum, as well as those produced by nerves. We also were able to investigate the response of blastema cells to experimentally regulated changes in BMP signaling. Blastema cells responded to all of these signals by increasing the rate of proliferation and the level of expression of the blastema marker gene, Prrx-1. The organotypic slice culture model provides the opportunity to identify and characterize the spatial and temporal co-regulation of pathways in order to induce and enhance a regenerative response.

  17. Regulation of Axolotl (Ambystoma mexicanum Limb Blastema Cell Proliferation by Nerves and BMP2 in Organotypic Slice Culture.

    Directory of Open Access Journals (Sweden)

    Jeffrey Lehrberg

    Full Text Available We have modified and optimized the technique of organotypic slice culture in order to study the mechanisms regulating growth and pattern formation in regenerating axolotl limb blastemas. Blastema cells maintain many of the behaviors that are characteristic of blastemas in vivo when cultured as slices in vitro, including rates of proliferation that are comparable to what has been reported in vivo. Because the blastema slices can be cultured in basal medium without fetal bovine serum, it was possible to test the response of blastema cells to signaling molecules present in serum, as well as those produced by nerves. We also were able to investigate the response of blastema cells to experimentally regulated changes in BMP signaling. Blastema cells responded to all of these signals by increasing the rate of proliferation and the level of expression of the blastema marker gene, Prrx-1. The organotypic slice culture model provides the opportunity to identify and characterize the spatial and temporal co-regulation of pathways in order to induce and enhance a regenerative response.

  18. The Effect of Electrospun Gelatin Fibers Alignment on Schwann Cell and Axon Behavior and Organization in the Perspective of Artificial Nerve Design.

    Science.gov (United States)

    Gnavi, Sara; Fornasari, Benedetta Elena; Tonda-Turo, Chiara; Laurano, Rossella; Zanetti, Marco; Ciardelli, Gianluca; Geuna, Stefano

    2015-01-01

    Electrospun fibrous substrates mimicking extracellular matrices can be prepared by electrospinning, yielding aligned fibrous matrices as internal fillers to manufacture artificial nerves. Gelatin aligned nano-fibers were prepared by electrospinning after tuning the collector rotation speed. The effect of alignment on cell adhesion and proliferation was tested in vitro using primary cultures, the Schwann cell line, RT4-D6P2T, and the sensory neuron-like cell line, 50B11. Cell adhesion and proliferation were assessed by quantifying at several time-points. Aligned nano-fibers reduced adhesion and proliferation rate compared with random fibers. Schwann cell morphology and organization were investigated by immunostaining of the cytoskeleton. Cells were elongated with their longitudinal body parallel to the aligned fibers. B5011 neuron-like cells were aligned and had parallel axon growth when cultured on the aligned gelatin fibers. The data show that the alignment of electrospun gelatin fibers can modulate Schwann cells and axon organization in vitro, suggesting that this substrate shows promise as an internal filler for the design of artificial nerves for peripheral nerve reconstruction.

  19. Effects of transcutaneous electrical nerve stimulation (TENS) on cognition, behavior, and the rest-activity rhythm in children with attention deficit hyperactivity disorder, combined type

    NARCIS (Netherlands)

    Jonsdottir, S; Bouma, A; Sergeant, JA; Scherder, EJA; Bouma, J.M.

    2004-01-01

    Objective. The aim of this study was to examine the effects of transcutaneous electrical nerve stimulation (TENS) on cognition, behavior, and the rest-activity rhythm in children with attention deficit hyperactivity disorder, combined type (ADHD-CT). Methods. Twenty-two children diagnosed with ADHD-

  20. Enhanced sympathetic nerve activity induced by neonatal colon inflammation induces gastric hypersensitivity and anxiety-like behavior in adult rats.

    Science.gov (United States)

    Winston, John H; Sarna, Sushil K

    2016-07-01

    Gastric hypersensitivity (GHS) and anxiety are prevalent in functional dyspepsia patients; their underlying mechanisms remain unknown largely because of lack of availability of live visceral tissues from human subjects. Recently, we demonstrated in a preclinical model that rats subjected to neonatal colon inflammation show increased basal plasma norepinephrine (NE), which contributes to GHS through the upregulation of nerve growth factor (NGF) expression in the gastric fundus. We tested the hypothesis that neonatal colon inflammation increases anxiety-like behavior and sympathetic nervous system activity, which upregulates the expression of NGF to induce GHS in adult life. Chemical sympathectomy, but not adrenalectomy, suppressed the elevated NGF expression in the fundus muscularis externa and GHS. The measurement of heart rate variability showed a significant increase in the low frequency-to-high frequency ratio in GHS vs. the control rats. Stimulus-evoked release of NE from the fundus muscularis externa strips was significantly greater in GHS than in the control rats. Tyrosine hydroxylase expression was increased in the celiac ganglia of the GHS vs. the control rats. We found an increase in trait but not stress-induced anxiety-like behavior in GHS rats in an elevated plus maze. We concluded that neonatal programming triggered by colon inflammation upregulates tyrosine hydroxylase in the celiac ganglia, which upregulates the release of NE in the gastric fundus muscularis externa. The increase of NE release from the sympathetic nerve terminals concentration dependently upregulates NGF, which proportionately increases the visceromotor response to gastric distention. Neonatal programming concurrently increases anxiety-like behavior in GHS rats. PMID:27151940

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

    Institute of Scientific and Technical Information of China (English)

    FANG Huang; WANG Junfang; CHEN Anmin

    2006-01-01

    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 Dubecco-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 immunocytochemical staining. At the same time, rats were subjected to behavioral tests by using the open-field BBB scoring system. Immunocytochemical 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 astrocytes. MSCs and NGF can promote axonal regeneration and improve functional recovery. There might exist a synergistic effect between MSCs and NGF.

  2. Supramolecular assembly of biological molecules purified from bovine nerve cells: from microtubule bundles and necklaces to neurofilament networks

    International Nuclear Information System (INIS)

    With the completion of the human genome project, the biosciences community is beginning the daunting task of understanding the structures and functions of a large number of interacting biological macromolecules. Examples include the interacting molecules involved in the process of DNA condensation during the cell cycle, and in the formation of bundles and networks of filamentous actin proteins in cell attachment, motility and cytokinesis. In this proceedings paper we present examples of supramolecular assembly based on proteins derived from the vertebrate nerve cell cytoskeleton. The axonal cytoskeleton in vertebrate neurons provides a rich example of bundles and networks of neurofilaments, microtubules (MTs) and filamentous actin, where the nature of the interactions, structures, and structure-function correlations remains poorly understood. We describe synchrotron x-ray diffraction, electron microscopy, and optical imaging data, in reconstituted protein systems purified from bovine central nervous system, which reveal unexpected structures not predicted by current electrostatic theories of polyelectrolyte bundling, including three-dimensional MT bundles and two-dimensional MT necklaces

  3. Direct Gene Transfer into Rabbit Peripheral Nerve in vivo

    Institute of Scientific and Technical Information of China (English)

    张世强; 张经歧; 张英泽; 刘玲

    2001-01-01

    Exogenous gene suture was used to achieve peripheral nerve anastomoses to probe into the feasibility that the sites of anastomoses of nerves directly transfer gene and thus enable gene to be expressed at the sites of anastomoses under the condition that perfect nerve anastomoses are ensured. PCMVβ plasmid containing cytomegalovirus promoter (CMV promoter) and Escherichia coli (E.coli) β-Galactosidase (β-Gal) structural gene (lacZ gene) was conducted. A soaked medical 8-0nylon suture was used to perform epineurial repair of rabbit sciatic nerve. In the control group a suture soaked in sucrose PBS was used, while in the experimental group a suture soaked in PCMVβ plasmid solution was applied. The sites of anastomoses of nerves by stages were taken out, and β-Gal histochemical staining was performed and β-Gal enzyme activity was assayed with 5-bromo-4-chloro-3-indolyl-β-D-galactoside. Results showed that the sites of anastomoses of nerves were taken out 2 days, 7 days, 14 days and 30 days respectively after the operation. The β-Gal histochemical stains at the sites of anastomoses showed no indigo positive cells at different stages in the control group, whereas displayed indigo positive cells in the experimental group. In the control group, no β-Gal enzyme activity was detected at different stages after operation, but in the experimental group, β-Gal enzyme activity could be detected from the 3rd day to the 30th day after operation. It was concluded that by using exogenous gene suture, exogenous gene could be transferred to the sites of peripheral nerve and expressed the exogenous gene expression products with bioactivity, which provided the feasibility of using gene therapy to accelerate the recovery of nerve function.

  4. Peptide functionalized polyhydroxyalkanoate nanofibrous scaffolds enhance Schwann cells activity

    NARCIS (Netherlands)

    Masaeli, E.; Wieringa, P.A.; Morshed, M.; Nasr-Esfahani, M.H.; Sadri, S.; Blitterswijk, van C.A.; Moroni, L.

    2014-01-01

    Interactions between Schwann cells (SCs) and scaffolds are important for tissue development during nerve regeneration, because SCs physiologically assist in directing the growth of regenerating axons. In this study, we prepared electrospun scaffolds combining poly (3-hydroxybutyrate) (PHB) and poly

  5. Cutaneous nerve entrapment syndrome

    Institute of Scientific and Technical Information of China (English)

    DongFuhui

    2004-01-01

    The cutaneous nerve entrapment syndrome is named that, the cutaneous nerve's functional disorder caused by some chronic entrapment, moreover appears a series of nerve's feeling obstacle,vegetative nerve function obstacle, nutrition obstacle, even motor function obstacle in various degree.

  6. Nerve biopsy (image)

    Science.gov (United States)

    Nerve biopsy is the removal of a small piece of nerve for examination. Through a small incision, a sample ... is removed and examined under a microscope. Nerve biopsy may be performed to identify nerve degeneration, identify ...

  7. BDNF Increases Survival and Neuronal Differentiation of Human Neural Precursor Cells Cotransplanted with a Nanofiber Gel to the Auditory Nerve in a Rat Model of Neuronal Damage

    Directory of Open Access Journals (Sweden)

    Yu Jiao

    2014-01-01

    Full Text Available Objectives. To study possible nerve regeneration of a damaged auditory nerve by the use of stem cell transplantation. Methods. We transplanted HNPCs to the rat AN trunk by the internal auditory meatus (IAM. Furthermore, we studied if addition of BDNF affects survival and phenotypic differentiation of the grafted HNPCs. A bioactive nanofiber gel (PA gel, in selected groups mixed with BDNF, was applied close to the implanted cells. Before transplantation, all rats had been deafened by a round window niche application of β-bungarotoxin. This neurotoxin causes a selective toxic destruction of the AN while keeping the hair cells intact. Results. Overall, HNPCs survived well for up to six weeks in all groups. However, transplants receiving the BDNF-containing PA gel demonstrated significantly higher numbers of HNPCs and neuronal differentiation. At six weeks, a majority of the HNPCs had migrated into the brain stem and differentiated. Differentiated human cells as well as neurites were observed in the vicinity of the cochlear nucleus. Conclusion. Our results indicate that human neural precursor cells (HNPC integration with host tissue benefits from additional brain derived neurotrophic factor (BDNF treatment and that these cells appear to be good candidates for further regenerative studies on the auditory nerve (AN.

  8. Minocycline is cytoprotective in human trabecular meshwork cells and optic nerve head astrocytes by increasing expression of XIAP, survivin, and Bcl-2

    Directory of Open Access Journals (Sweden)

    Marcus Kernt

    2010-06-01

    Full Text Available Marcus Kernt, Aljoscha S Neubauer, Kirsten H Eibl, Armin Wolf, Michael W Ulbig, Anselm Kampik, Cristoph HirneissDepartment of Ophthalmology, Ludwig-Maximilians-University, Munich, GermanyIntroduction: Primary open-angle glaucoma (POAG is one of the leading causes of blindness. Activation of optic nerve head astrocytes (ONHA and loss of trabecular meshwork cells (TMC are pathognomonic for this neurodegenerative disease. Oxidative stress and elevated levels of transforming growth factor beta (TGFβ play an important role in the pathogenesis of POAG. This study investigates the possible antiapoptotic and cytoprotective effects of minocycline on TMC and ONHA under oxidative stress and increased TGFβ levels.Methods: TMC and ONHA were treated with minocycline 1–150 μM. Possible toxic effects and IC50 were evaluated after 48 hours. Cell proliferation and viability were examined in order to assess the protective effects of minocycline on TMC and ONHA. Expression of Bcl-2, XIAP, and survivin, as well as their mRNA expression, were assessed by real time polymerase chain reaction (RT-PCR and Western Blot analysis 48 hours after treatment with minocycline alone and additional incubation with TGFβ-2 or oxidative stress.Results: Minocycline 1–75 μM showed no toxic effects on TMC and ONHA. Under conditions of oxidative stress, both TMC and ONHA showed an increase in viability and an ability to proliferate when treated with minocycline 20–40 μM. RT-PCR and Western blotting yielded an overexpression of Bcl-2, XIAP, and survivin when TMC or ONHA were treated with minocycline 20–40 μM under conditions of oxidative stress and when additionally incubated with TGFβ-2.Conclusion: Minocycline up to 75 μM does not have toxic effects on TMC and ONHA. Treatment with minocycline 20–40 μM led to increased viability and proliferation under oxidative stress and TGFβ-2, as well as overexpression of Bcl-2, XIAP, and survivin. This protective pathway may help

  9. Increased production of omega-3 fatty acids protects retinal ganglion cells after optic nerve injury in mice.

    Science.gov (United States)

    Peng, Shanshan; Shi, Zhe; Su, Huanxing; So, Kwok-Fai; Cui, Qi

    2016-07-01

    Injury to the central nervous system causes progressive degeneration of injured axons, leading to loss of the neuronal bodies. Neuronal survival after injury is a prerequisite for successful regeneration of injured axons. In this study, we investigated the effects of increased production of omega-3 fatty acids and elevation of cAMP on retinal ganglion cell (RGC) survival and axonal regeneration after optic nerve (ON) crush injury in adult mice. We found that increased production of omega-3 fatty acids in mice enhanced RGC survival, but not axonal regeneration, over a period of 3 weeks after ON injury. cAMP elevation promoted RGC survival in wild type mice, but no significant difference in cell survival was seen in mice over-producing omega-3 fatty acids and receiving intravitreal injections of CPT-cAMP, suggesting that cAMP elevation protects RGCs after injury but does not potentiate the actions of the omega-3 fatty acids. The observed omega-3 fatty acid-mediated neuroprotection is likely achieved partially through ERK1/2 signaling as inhibition of this pathway by PD98059 hindered, but did not completely block, RGC protection. Our study thus enhances our current understanding of neural repair after CNS injury, including the visual system.

  10. Effect of Aβ1-40 on membrane permeability and intracellular free Ca2+ of nerve cells

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The effects of soluble and fibrillar Aβ1-40 on membrane permeability and intracellular free Ca2+ of nerve cells were investigated by the laser confocal microscopy. Results indicate that: i) Effects of soluble and fibrillar Aβ1-40 on cell membrane permeability are both concentration-de- pendent. Soluble Aβ1-40 increases membrane permeability only at concentration of 3 ?mol/L, while the toxic effect of fibrillar Aβ1-40 is much stronger, its evident effect begins from 1 ?mol/L. When its concentration rose to 3 ?mol/L, not only the membrane permeability increased, but also the nuclear membrane broke seriously. ii) Both soluble and fibrillar Aβ1-40 at high concentrations increased the intracellular free Ca2+, and the increased amplitudes are concentration-dependent. However, the fibrillar one induces the increase of intracellular Ca2+ much quicker and synchronously. These results indicate that some correlation exists between the neurotoxicity of high concentration soluble and fibrillar Aβ1-40 and the change of physico-chemical properties and intracellular Ca ion imbalance.

  11. Activation of axonal Kv7 channels in human peripheral nerve by flupirtine but not placebo - therapeutic potential for peripheral neuropathies: results of a randomised controlled trial

    OpenAIRE

    Fleckenstein, Johannes; Sittl, Ruth; Averbeck, Beate; Lang, Philip M; Irnich, Dominik; Richard W Carr

    2013-01-01

    Background: Flupirtine is an analgesic with muscle-relaxing properties that activates Kv7 potassium channels. Kv7 channels are expressed along myelinated and unmyelinated peripheral axons where their activation is expected to reduce axonal excitability and potentially contribute to flupirtine’s clinical profile. Trial design: To investigate the electrical excitability of peripheral myelinated axons following orally administered flupirtine, in-vitro experiments on isolated peripheral nerve s...

  12. Activation of axonal Kv7 channels in human peripheral nerve by flupirtine but not placebo - therapeutic potential for peripheral neuropathies: results of a randomised controlled trial

    OpenAIRE

    Fleckenstein, Johannes; Sittl, Ruth; Averbeck, Beate; Lang, Philip M; Irnich, Dominik; Richard W Carr

    2013-01-01

    Background Flupirtine is an analgesic with muscle-relaxing properties that activates Kv7 potassium channels. Kv7 channels are expressed along myelinated and unmyelinated peripheral axons where their activation is expected to reduce axonal excitability and potentially contribute to flupirtine’s clinical profile. Trial design To investigate the electrical excitability of peripheral myelinated axons following orally administered flupirtine, in-vitro experiments on isolated peripheral nerve segme...

  13. Nitric oxide impacts on angiotensin AT2 receptor modulation of high-pressure baroreflex control of renal sympathetic nerve activity in anaesthetized rats

    OpenAIRE

    Abdulla, M H; Johns, E. J.

    2013-01-01

    Aim Nitric oxide (NO) interacts with the local brain renin-angiotensin system to modulate sympathetic outflow and cardiovascular homoeostasis. This study investigated whether NO influenced the ability of angiotensin AT2 receptor activation to modify the high-pressure baroreceptor regulation of renal sympathetic nerve activity (RSNA) and heart rate (HR). Methods Anaesthetized (chloralose/urethane) rats were prepared to allow generation of baroreflex gain curves for RSNA or HR following intrace...

  14. Skeletal muscle reflex-mediated changes in sympathetic nerve activity are abnormal in spontaneously hypertensive rats

    OpenAIRE

    Mizuno, Masaki; Murphy, Megan N.; Mitchell, Jere H.; Smith, Scott A.

    2011-01-01

    In hypertension, the blood pressure response to exercise is exaggerated. We demonstrated previously that this heightened pressor response to physical activity is mediated by an overactive skeletal muscle exercise pressor reflex (EPR), with important contributions from its metaboreflex and mechanoreflex components. However, the mechanisms driving the abnormal blood pressure response to EPR activation are largely unknown. Recent evidence in humans suggests that the muscle metaboreflex partially...

  15. Delayed peripheral nerve repair: methods, including surgical ′cross-bridging′ to promote nerve regeneration

    Directory of Open Access Journals (Sweden)

    Tessa Gordon

    2015-01-01

    Full Text Available Despite the capacity of Schwann cells to support peripheral nerve regeneration, functional recovery after nerve injuries is frequently poor, especially for proximal injuries that require regenerating axons to grow over long distances to reinnervate distal targets. Nerve transfers, where small fascicles from an adjacent intact nerve are coapted to the nerve stump of a nearby denervated muscle, allow for functional return but at the expense of reduced numbers of innervating nerves. A 1-hour period of 20 Hz electrical nerve stimulation via electrodes proximal to an injury site accelerates axon outgrowth to hasten target reinnervation in rats and humans, even after delayed surgery. A novel strategy of enticing donor axons from an otherwise intact nerve to grow through small nerve grafts (cross-bridges into a denervated nerve stump, promotes improved axon regeneration after delayed nerve repair. The efficacy of this technique has been demonstrated in a rat model and is now in clinical use in patients undergoing cross-face nerve grafting for facial paralysis. In conclusion, brief electrical stimulation, combined with the surgical technique of promoting the regeneration of some donor axons to ′protect′ chronically denervated Schwann cells, improves nerve regeneration and, in turn, functional outcomes in the management of peripheral nerve injuries.

  16. Effect of oblique nerve grafting on peripheral nerve regeneration in rats.

    Science.gov (United States)

    Kotulska, Katarzyna; Marcol, Wiesław; Larysz-Brysz, Magdalena; Tendera, Zofia; Malinowska-Kołodziej, Izabela; Slusarczyk, Wojciech; Jedrzejowska-Szypułka, Halina; Lewin-Kowalik, Joanna

    2006-01-01

    Current methods of peripheral nerve repair are to rejoin cut nerve stumps directly or to bridge large gaps with autologous nerve grafts. In both cases the surface of nerve stump endings is typically cut perpendicularly to the long axis of the nerve. The outcome of such operations, however, is still not satisfactory. In this study, we examine the effect of oblique nerve cutting and grafting on morphological as well as functional features of regeneration. In adult rats, sciatic nerve was cut and rejoined either directly or using an autologous graft, at 90 degrees or 30 degrees angle. Functional regeneration was assessed by walking track analysis during 12-week follow-up. Afterwards muscle weight was measured and histological studies were performed. The latter included nerve fibers and Schwann cells counting, as well as visualization of scar formation and epineural fibrosis. Nerves cut obliquely and rejoined showed better functional recovery than perpendicularly transected. Similar effect was observed after oblique grafting when compared to perpendicular one. Numbers of nerve fibers growing into the distal stump of the nerve as well as the number of Schwann cells were significantly higher in obliquely than in perpendicularly operated nerves. Moreover, growing axons were arranged more regularly following oblique treatment. These data indicate that joining or grafting the nerve stumps at acute angle is a more profitable method of nerve repair than the standard procedure performed at right angle. PMID:17066410

  17. Safety profile of bone marrow mononuclear stem cells in the rehabilitation of patients with posttraumatic facial nerve paralysis-a novel modality (phase one trial).

    Science.gov (United States)

    Aggarwal, Sushil Kumar; Gupta, Ashok Kumar; Modi, Manish; Gupta, Rijuneeta; Marwaha, Neelam

    2012-08-01

    Objectives The objectives of this study were to study the safety profile and role of mononuclear stem cells in the rehabilitation of posttraumatic facial nerve paralysis not improving with conventional treatment. Study Design This is a prospective nonrandomized controlled trial. Study Setting This study is conducted at Postgraduate Institute of Medical Education and Research (PGIMER), Chandigarh between July, 2007 and December, 2008. Patients We included eight patients of either sex aged between 18 and 60 years of posttraumatic facial nerve paralysis not improving with conventional treatment presented to PGIMER, Chandigarh between July 2007 and December 2008. Methods All patients underwent preoperative electroneuronography (ENoG), clinical photography, and high-resolution computed tomography (HRCT) temporal bone. All patients then underwent facial nerve decompression and stem cell implantation. Stem cells processing was done in well-equipped bone marrow laboratory. Postoperatively, all patients underwent repeat ENoG and clinical photography at 3 and 6 months to assess for objective and clinical improvement. Clinical improvement was graded according to modified House-Brackmann grading system. Intervention Done All patients of posttraumatic facial nerve paralysis who were not improving with conventional surgical treatment were subjected to facial nerve decompression and stem cell implantation. Main Outcome Measures All patients who were subjected to stem cell implantation were followed up for 6 months to assess for any adverse effects of stem cell therapy on human beings; no adverse effects were seen in any of our patients after more than 6 months of follow-up. Results Majority of the patients were male, with motor vehicle accidents as the most common cause of injury in our series. Majority had longitudinal fractures on HRCT temporal bone. The significant improvement in ENoG amplitude was seen between preoperative and postoperative amplitudes on

  18. Regeneração de nervos periféricos: terapia celular e fatores neurotróficos Peripheral nerve regeneration: cell therapy and neurotrophic factors

    Directory of Open Access Journals (Sweden)

    Alessandra Deise Sebben

    2011-01-01

    surgical intervention is rare. Many surgical techniques can be used for nerve repair. Among these, the tubulization technique can be highlighted: this allows regenerative factors to be introduced into the chamber. Cell therapy and tissue engineering have arisen as an alternative for stimulating and aiding peripheral nerve regeneration. Therefore, the aim of this review was to provide a survey and analysis on the results from experimental and clinical studies that used cell therapy and tissue engineering as tools for optimizing the regeneration process. The articles used came from the LILACS, Medline and SciELO scientific databases. Articles on the use of stem cells, Schwann cells, growth factors, collagen, laminin and platelet-rich plasma for peripheral nerve repair were summarized over the course of the review. Based on these studies, it could be concluded that the use of stem cells derived from different sources presents promising results relating to nerve regeneration, because these cells have a capacity for neuronal differentiation, thus demonstrating effective functional results. The use of tubes containing bioactive elements with controlled release also optimizes the nerve repair, thus promoting greater myelination and axonal growth of peripheral nerves. Another promising treatment is the use of platelet-rich plasma, which not only releases growth factors that are important in nerve repair, but also serves as a carrier for exogenous factors, thereby stimulating the proliferation of specific cells for peripheral nerve repair.

  19. Ionic channels and hormone release from peptidergic nerve terminals.

    Science.gov (United States)

    Lemos, J R; Nordmann, J J

    1986-09-01

    Although there is considerable evidence that depolarization of nerve cell terminals leads to the entry of Ca2+ and to the secretion of neurohormones and neurotransmitters, the details of how ionic currents control the release of neuroactive substances from nerve terminals are unknown. The small size of most nerve terminals has precluded direct analysis of membrane ionic currents and their influence on secretion. We now report that it is possible, using patch-clamp techniques, to study stimulus--secretion coupling in isolated peptidergic nerve terminals. Sinus gland terminals from Cardisoma are easily isolated following collagenase treatment and appear morphologically and electrically very similar to non-dissociated nerve endings. We have observed two types of single-channel currents not previously described. The first ('f') channel is activated by intracellular Na+ and the second ('s') by intracellular Ca2+. Both show little selectivity between Na+ and K+. In symmetrical K+, these cation channels have mean conductances of 69 and 213 pS, respectively. Furthermore, at least three types of Ca2+ channels can be reconstituted from nerve terminal membranes prepared from sinus glands. Nerve terminals can also be isolated from the rat neural lobe. These neurosecretosomes release oxytocin and vasopressin, in response to membrane depolarization, only in the presence of external Ca2+. The depolarization of the nerve endings is associated with an increase in intracellular free Ca2+ concentration and this increase, measured using a fluorescent indicator, is abolished by Ca2+ channel blockers. Channels similar in their properties to the f and s channels also exist in rat neural lobe endings. Since these channels have not been found in other neurones or neuronal structures they may be unique to peptidergic nerve terminals.

  20. Changes in brain-derived neurotrophic factor expression after transplanting microencapsulated sciatic nerve cells of rabbits into injured spinal cord of rats

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    BACKGROUND: Changes of brain-derived neurotrophic factor (BDNF) expression reflect function of nerve cells; meanwhile, they play a significant role in researching interventions on plerosis of nerve injury.OBJECTIVE: To observe and compare the effects on changes of BDNF expression in rats with spinal cord injury between microencapsulated sciatic nerve cells of rabbits and only transplanting sciatic nerve cells of rabbits.DESIGN: Randomized controlled animal study.SETTING: Medical School of Jiujiang College.MATERIALS: The experiment was carried out in the Medical Science Researching Center, Jiujiang College from May 2004 to May 2006. A total of 90 healthy adult SD rats, weighing 250 - 300 g, of either gender; and 10 rabbits, weighing 2.0 - 2.5 kg, of either gender, were provided by Jiangxi Experimental Animal Center.METHODS: Sciatic nerve tissue of rabbits was separated to make cell suspension. After centrifugation,suspension was mixed with 15 g/L alginate saline solution and ejaculated to 20 mmol/L barium chloride saline solution by double-cavity ejaculator. The obtained cell microcapsules were suspended in saline. Rats were randomly divided into microencapsulated group, only suspension group, and only injured group with 30 animals in each group. After anesthesia, T10 spinous process and vertebra lamina of rats in the former two groups were exposed. Spinal cord tissue in 2-mm length was removed from rats by spinal cord right hemi-section. The gelatin sponges with the size of 2 mm × 2 mm × 2 mm were grafted as filing cage,and absorbed 10 μμ L microencapsulated sciatic nerve cells of rabbit in the microencapsulated group and 10 μ L sciatic nerve cells of rabbits in the only suspension group; respectively. No graft was placed in the only injured group.MAIN OUTCOME MEASURES: On the 1st, 3rd, 7th, 14th and 28th days after operation,immunohistochemistry (SABC technique) was used to detect distribution and amount of positive-reactive neurons in BDNF of spinal cord

  1. Contralateral Metabolic Activation Related to Plastic Changes in the Spinal Cord after Peripheral Nerve Injury in Rats

    OpenAIRE

    Ran Won; Bae Hwan Lee

    2015-01-01

    We have previously reported the crossed-withdrawal reflex in which the rats with nerve injury developed behavioral pain responses of the injured paw to stimuli applied to the contralateral uninjured paw. This reflex indicates that contralateral plastic changes may occur in the spinal cord after unilateral nerve injury. The present study was performed to elucidate the mechanisms and morphological correlates underlying the crossed-withdrawal reflex by using quantitative 14C-2-deoxyglucose (2-DG...

  2. Development of polydimethylsiloxane substrates with tunable elastic modulus to study cell mechanobiology in muscle and nerve.

    Directory of Open Access Journals (Sweden)

    Rachelle N Palchesko

    Full Text Available Mechanics is an important component in the regulation of cell shape, proliferation, migration and differentiation during normal homeostasis and disease states. Biomaterials that match the elastic modulus of soft tissues have been effective for studying this cell mechanobiology, but improvements are needed in order to investigate a wider range of physicochemical properties in a controlled manner. We hypothesized that polydimethylsiloxane (PDMS blends could be used as the basis of a tunable system where the elastic modulus could be adjusted to match most types of soft tissue. To test this we formulated blends of two commercially available PDMS types, Sylgard 527 and Sylgard 184, which enabled us to fabricate substrates with an elastic modulus anywhere from 5 kPa up to 1.72 MPa. This is a three order-of-magnitude range of tunability, exceeding what is possible with other hydrogel and PDMS systems. Uniquely, the elastic modulus can be controlled independently of other materials properties including surface roughness, surface energy and the ability to functionalize the surface by protein adsorption and microcontact printing. For biological validation, PC12 (neuronal inducible-pheochromocytoma cell line and C2C12 (muscle cell line were used to demonstrate that these PDMS formulations support cell attachment and growth and that these substrates can be used to probe the mechanosensitivity of various cellular processes including neurite extension and muscle differentiation.

  3. Development of polydimethylsiloxane substrates with tunable elastic modulus to study cell mechanobiology in muscle and nerve.

    Science.gov (United States)

    Palchesko, Rachelle N; Zhang, Ling; Sun, Yan; Feinberg, Adam W

    2012-01-01

    Mechanics is an important component in the regulation of cell shape, proliferation, migration and differentiation during normal homeostasis and disease states. Biomaterials that match the elastic modulus of soft tissues have been effective for studying this cell mechanobiology, but improvements are needed in order to investigate a wider range of physicochemical properties in a controlled manner. We hypothesized that polydimethylsiloxane (PDMS) blends could be used as the basis of a tunable system where the elastic modulus could be adjusted to match most types of soft tissue. To test this we formulated blends of two commercially available PDMS types, Sylgard 527 and Sylgard 184, which enabled us to fabricate substrates with an elastic modulus anywhere from 5 kPa up to 1.72 MPa. This is a three order-of-magnitude range of tunability, exceeding what is possible with other hydrogel and PDMS systems. Uniquely, the elastic modulus can be controlled independently of other materials properties including surface roughness, surface energy and the ability to functionalize the surface by protein adsorption and microcontact printing. For biological validation, PC12 (neuronal inducible-pheochromocytoma cell line) and C2C12 (muscle cell line) were used to demonstrate that these PDMS formulations support cell attachment and growth and that these substrates can be used to probe the mechanosensitivity of various cellular processes including neurite extension and muscle differentiation.

  4. Perfusion of isolated carotid sinus with hydrogen sulfide attenuated the renal sympathetic nerve activity in anesthetized male rats.

    Science.gov (United States)

    Guo, Q; Wu, Y; Xue, H; Xiao, L; Jin, S; Wang, R

    2016-07-18

    The purpose of the present study was to define the indirect central effect of hydrogen sulfide (H(2)S) on baroreflex control of sympathetic outflow. Perfusing the isolated carotid sinus with sodium hydrosulfide (NaHS), a H(2)S donor, the effect of H(2)S was measured by recording changes of renal sympathetic nerve activity (RSNA) in anesthetized male rats. Perfusion of isolated carotid sinus with NaHS (25, 50, 100 micromol/l) dose and time-dependently inhibited sympathetic outflow. Preconditioning of glibenclamide (20 micromol/l), a ATP-sensitive K(+) channels (K(ATP)) blocker, the above effect of NaHS was removed. With 1, 4-dihydro-2, 6-dimethyl-5-nitro-4-(2-[trifluoromethyl] phenyl) pyridine-3-carboxylic acid methyl ester (Bay K8644, 500 nmol/l) pretreatment, which is an agonist of L-calcium channels, the effect of NaHS was eliminated. Perfusion of cystathionine gamma-lyase (CSE) inhibitor, DL-propargylglycine (PPG, 200 micromol/l), increased sympathetic outflow. The results show that exogenous H(2)S in the carotid sinus inhibits sympathetic outflow. The effect of H(2)S is attributed to opening K(ATP) channels and closing the L-calcium channels.

  5. Perfusion of isolated carotid sinus with hydrogen sulfide attenuated the renal sympathetic nerve activity in anesthetized male rats.

    Science.gov (United States)

    Guo, Q; Wu, Y; Xue, H; Xiao, L; Jin, S; Wang, R

    2016-07-18

    The purpose of the present study was to define the indirect central effect of hydrogen sulfide (H(2)S) on baroreflex control of sympathetic outflow. Perfusing the isolated carotid sinus with sodium hydrosulfide (NaHS), a H(2)S donor, the effect of H(2)S was measured by recording changes of renal sympathetic nerve activity (RSNA) in anesthetized male rats. Perfusion of isolated carotid sinus with NaHS (25, 50, 100 micromol/l) dose and time-dependently inhibited sympathetic outflow. Preconditioning of glibenclamide (20 micromol/l), a ATP-sensitive K(+) channels (K(ATP)) blocker, the above effect of NaHS was removed. With 1, 4-dihydro-2, 6-dimethyl-5-nitro-4-(2-[trifluoromethyl] phenyl) pyridine-3-carboxylic acid methyl ester (Bay K8644, 500 nmol/l) pretreatment, which is an agonist of L-calcium channels, the effect of NaHS was eliminated. Perfusion of cystathionine gamma-lyase (CSE) inhibitor, DL-propargylglycine (PPG, 200 micromol/l), increased sympathetic outflow. The results show that exogenous H(2)S in the carotid sinus inhibits sympathetic outflow. The effect of H(2)S is attributed to opening K(ATP) channels and closing the L-calcium channels. PMID:26988151

  6. Arterial baroreceptor reflex control of renal sympathetic nerve activity following chronic myocardial infarction in male, female, and ovariectomized female rats.

    Science.gov (United States)

    Pinkham, Maximilian I; Whalley, Gillian A; Guild, Sarah-Jane; Malpas, Simon C; Barrett, Carolyn J

    2015-07-15

    There is controversy regarding whether the arterial baroreflex control of renal sympathetic nerve activity (SNA) in heart failure is altered. We investigated the impact of sex and ovarian hormones on changes in the arterial baroreflex control of renal SNA following a chronic myocardial infarction (MI). Renal SNA and arterial pressure were recorded in chloralose-urethane anesthetized male, female, and ovariectomized female (OVX) Wistar rats 6-7 wk postsham or MI surgery. Animals were grouped according to MI size (sham, small and large MI). Ovary-intact females had a lower mortality rate post-MI (24%) compared with both males (38%) and OVX (50%) (P renal SNA. As a result, the male large MI group (49 ± 6 vs. 84 ± 5% in male sham group) and OVX large MI group (37 ± 3 vs. 75 ± 5% in OVX sham group) displayed significantly reduced arterial baroreflex range of control of normalized renal SNA (P renal SNA was unchanged regardless of MI size. In males and OVX there was a significant, positive correlation between left ventricle (LV) ejection fraction and arterial baroreflex range of control of normalized renal SNA, but not absolute renal SNA, that was not evident in ovary-intact females. The current findings demonstrate that the arterial baroreflex control of renal SNA post-MI is preserved in ovary-intact females, and the state of left ventricular dysfunction significantly impacts on the changes in the arterial baroreflex post-MI.

  7. A functional model and simulation of spinal motor pools and intrafascicular recordings of motoneuron activity in peripheral nerve

    Directory of Open Access Journals (Sweden)

    Mohamed N. Abdelghani

    2014-11-01

    Full Text Available Decoding motor intent from recorded neural signals is essential for the development of effective neural-controlled prostheses. To facilitate the development of online decoding algorithms we have developed a software platform to simulate neural motor signals recorded with peripheral nerve electrodes, such as longitudinal intrafascicular electrodes (LIFEs. The simulator uses stored motor intent signals to drive a pool of simulated motoneurons with various spike shapes, recruitment characteristics, and firing frequencies. Each electrode records a weighted sum of a subset of simulated motoneuron activity patterns. As designed, the simulator facilitates development of a suite of test scenarios that would not be possible with actual data sets because, unlike with actual recordings, in the simulator the individual contributions to the simulated composite recordings are known and can be methodically varied across a set of simulation runs. In this manner, the simulation tool is suitable for iterative development of real-time decoding algorithms prior to definitive evaluation in amputee subjects with implanted electrodes. The simulation tool was used to produce data sets that demonstrate its ability to capture some features of neural recordings that pose challenges for decoding algorithms.

  8. Enteric plexuses of two choline-acetyltransferase transgenic mouse lines: chemical neuroanatomy of the fluorescent protein-expressing nerve cells.

    Science.gov (United States)

    Wilhelm, Márta; Lawrence, J Josh; Gábriel, Robert

    2015-02-01

    We studied cholinergic circuit elements in the enteric nervous system (ENS) of two distinct transgenic mouse lines in which fluorescent protein expression was driven by the choline-acetyltransferase (ChAT) promoter. In the first mouse line, green fluorescent protein was fused to the tau gene. This construct allowed the visualization of the fiber tracts and ganglia, however the nerve cells were poorly resolved. In the second mouse line (ChATcre-YFP), CRE/loxP recombination yielded cytosolic expression of yellow fluorescent protein (YFP). In these preparations the morphology of enteric neurons could be well studied. We also determined the neurochemical identity of ENS neurons in muscular and submucous layers using antibodies against YFP, calretinin (CALR), calbindin (CALB), and vasoactive intestinal peptide (VIP). Confocal microscopic imaging was used to visualize fluorescently-conjugated secondary antibodies. In ChATcre-YFP preparations, YFP was readily apparent in somatodendritic regions of ENS neurons. In the myenteric plexus, YFP/CALR/VIP staining revealed that 34% of cholinergic cells co-labeled with CALR. Few single-stained CR-positive cells were observed. Neither YFP nor CALR co-localized with VIP. In GFP/CALB/CALR staining, all co-localization combinations were represented. In the submucosal plexus, YFP/CALR/VIP staining revealed discrete neuronal populations. However, in separate preparations, double labeling was observed for YFP/CALR and CALR/VIP. In YFP/CALR/CALB staining, all combinations of double staining and triple labeling were verified. In conclusion, the neurochemical coding of ENS neurons in these mouse lines is consistent with many observations in non-transgenic animals. Thus, they provide useful tools for physiological and pharmacological studies on distinct neurochemical subtypes of ENS neurons. PMID:25592616

  9. Potential genotoxic effects of GSM-1800 exposure on human cutaneous and nerve cells

    International Nuclear Information System (INIS)

    Introduction The GSM-1800 signal has been in use for several years in Europe and questions raised about its potential biological effects, in view of the fact that, with respect to GSM-900, the increase in the carrier frequency corresponds to a more superficial absorption in the tissues. Consequently, the skin becomes an even more important target for the absorption of the radiofrequency radiation (R.F.R.) emitted by mobile phones. Nevertheless, brain tissues remain a critical target. Cells In order to determine whether R.F.R. at 1800 MHz could behave as a genotoxic agent, skin and brain cells were exposed to a 217-Hz-modulated GSM-1800 signal and assayed using the comet assay: (1) normal human epidermal keratinocytes (N.H.E.K.) and dermal fibroblasts (N.H.D.F.) which are cutaneous cells from epidermis and dermis respectively, and (2) the S.H. -S.Y.5.Y. and C.H.M.E.-5 human cell lines, which are neuroblastoma and micro-glial cells, respectively. Exposure The R.F.R. exposure system that was used in these experiments was manufactured by I.T. I.S. (Zurich, Switzerland). It consists in two shorted waveguides allowing to run exposed and sham conditions at the same time in the same culture incubator, at 37 Celsius degrees, 5% CO2. It is controlled by a software, which provides blind conditions until completion of data analysis. The specific absorption rate (S.A.R.) used was 2 W/kg, corresponding to the public exposure limit recommended by I.C.N.I.R.P. and the exposure duration was 48 hours. Comet assay At the end of the exposure, cells were removed from their Petri dish by trypsin/EDTA treatment, counted and 5 x 104 cells were used to detect DNA damage including single DNA breaks. Positive controls were performed using hydrogen peroxidase (1%, 1 hour). The genotoxic effects were detected using the alkaline comet assay kit (Trevigen slides) following the supplier procedure. Under these conditions, 6 independent experiments were performed for each cell type (2 Petri dishes

  10. Leptin into the rostral ventral lateral medulla (RVLM) augments renal sympathetic nerve activity and blood pressure

    OpenAIRE

    Barnes, Maria J.; David Harry McDougal

    2014-01-01

    Leptin is a hormone released from adipose tissue. While this hormone normally acts to reduce feeding behavior and increase energy expenditure, in obesity, resistance to these effects occurs even though the hormone is released in large amounts. Although leptin no longer works to suppress feeding in the obese, leptin retains its potent effects on other autonomic functions such as blood pressure regulation. Leptin has been associated with hypertension and increased sympathetic autonomic activ...

  11. Leptin into the rostral ventral lateral medulla (RVLM) augments renal sympathetic nerve activity and blood pressure

    OpenAIRE

    Barnes, Maria J.; McDougal, David H.

    2014-01-01

    Leptin is a hormone released from adipose tissue. While this hormone normally acts to reduce feeding behavior and increase energy expenditure, in obesity, resistance to these effects occurs even though the hormone is released in large amounts. Although leptin no longer works to suppress feeding in the obese, leptin retains its potent effects on other autonomic functions such as blood pressure regulation. Leptin has been associated with hypertension and increased sympathetic autonomic activity...

  12. Maintained inspiratory activity during proportional assist ventilation in surfactant-depleted cats early after surfactant instillation: phrenic nerve and pulmonary stretch receptor activity

    Directory of Open Access Journals (Sweden)

    Schaller Peter

    2006-03-01

    Full Text Available Abstract Background Inspiratory activity is a prerequisite for successful application of patient triggered ventilation such as proportional assist ventilation (PAV. It has recently been reported that surfactant instillation increases the activity of slowly adapting pulmonary stretch receptors (PSRs followed by a shorter inspiratory time (Sindelar et al, J Appl Physiol, 2005 [Epub ahead of print]. Changes in lung mechanics, as observed in preterm infants with respiratory distress syndrome and after surfactant treatment, might therefore influence the inspiratory activity when applying PAV early after surfactant treatment. Objective To investigate the regulation of breathing and ventilatory response in surfactant-depleted young cats during PAV and during continuous positive airway pressure (CPAP early after surfactant instillation in relation to phrenic nerve activity (PNA and the activity of PSRs. Methods Seven anesthetized, endotracheally intubated young cats were exposed to periods of CPAP and PAV with the same end-expiratory pressure (0.2–0.5 kPa before and after lung lavage and after surfactant instillation. PAV was set to compensate for 75% of the lung elastic recoil. Results Tidal volume and respiratory rate were higher with lower PaCO2 and higher PaO2 during PAV than during CPAP both before and after surfactant instillation (p Conclusion PSR activity and the control of breathing are maintained during PAV in surfactant-depleted cats early after surfactant instillation, with a higher ventilatory response and a lower breathing effort than during CPAP.

  13. Regulation of Schwann cell proliferation in cultured segments of the adult rat sciatic nerve

    DEFF Research Database (Denmark)

    Svenningsen, Åsa Fex; Kanje, M

    1998-01-01

    of Schwann cells. Removal of extracellular Ca2+ by addition of EGTA to the culture medium suppressed [3H] thymidine incorporation as did the calmodulin inhibitor 48/80. The Ca2+ ionophore A23187 increased incorporation. Staurosporin, an inhibitor of protein kinase C (PKC), suppressed [3H] thymidine...

  14. Potentiation of nerve growth factor-induced neurite outgrowth in PC12 cells by ifenprodil: the role of sigma-1 and IP3 receptors.

    Directory of Open Access Journals (Sweden)

    Tamaki Ishima

    Full Text Available In addition to both the α1 adrenergic receptor and N-methyl-D-aspartate (NMDA receptor antagonists, ifenprodil binds to the sigma receptor subtypes 1 and 2. In this study, we examined the effects of ifenprodil on nerve growth factor (NGF-induced neurite outgrowth in PC12 cells. Ifenprodil significantly potentiated NGF-induced neurite outgrowth, in a concentration-dependent manner. In contrast, the α1 adrenergic receptor antagonist, prazosin and the NMDA receptor NR2B antagonist, Ro 25-6981 did not alter NGF-induced neurite outgrowth. Potentiation of NGF-induced neurite outgrowth mediated by ifenprodil was significantly antagonized by co-administration of the selective sigma-1 receptor antagonist, NE-100, but not the sigma-2 receptor antagonist, SM-21. Similarly, ifenprodil enhanced NGF-induced neurite outgrowth was again significantly reduced by the inositol 1,4,5-triphosphate (IP(3 receptor antagonists, xestospongin C and 2-aminoethoxydiphenyl borate (2-APB treatment. Furthermore, BAPTA-AM, a chelator of intracellular Ca(2+, blocked the effects of ifenprodil on NGF-induced neurite outgrowth, indicating the role of intracellular Ca(2+ in the neurite outgrowth. These findings suggest that activation at sigma-1 receptors and subsequent interaction with IP(3 receptors may mediate the pharmacological effects of ifenprodil on neurite outgrowth.

  15. Stimulation of the greater occipital nerve increases metabolic activity in the trigeminal nucleus caudalis and cervical dorsal horn of the cat.

    Science.gov (United States)

    Goadsby, P J; Knight, Y E; Hoskin, K L

    1997-10-01

    Patients with primary headache syndromes often describe a distribution of pain that involves both frontal and occipital parts of the head. Such a distribution of pain does not respect the cutaneous sensory innervation of the head which would divide it into anterior (trigeminally innervated) and posterior (spinal nerve root innervated) regions. Studies of pain-producing intracranial structures, such as the superior sagittal sinus, have demonstrated that second order neurons as caudal as C2 are activated after either electrical or mechanical stimulation. For this study cats were anaesthetised with halothane (during surgery) and alpha-chloralose (60 mg/kg, i.p., then 20 mg/kg intravenous maintenance), paralysed (gallamine 6 mg/kg) and ventilated. The greater occipital nerve was isolated bilaterally and stimulated unilaterally using hook electrodes with stimuli of 100 V at 0.3 Hz. Metabolic activity in the caudal brain stem and upper cervical cord was measured using 2-deoxyglucose autoradiography and quantitative densitometry. Stimulation of the greater occipital nerve increased metabolic activity by 220% ipsilateral to stimulation and by a lesser amount contralaterally. Increases in metabolic activity were seen in the dorsal horn at the level of C1 and C2 as might be predicted from the cervical origin of the nerve. Neuronal activation appeared contiguous with the trigeminal nucleus caudalis and was in the same distribution as is seen when trigeminally-innervated structures are stimulated. These data suggest that the well recognised clinical phenomenon of pain at the front and back of the head and in the upper neck are likely to be a consequence of overlap of processing of nociceptive information at the level of the second order neurons. PMID:9414053

  16. A simple model of radial nerve injury in the rhesus monkey to evaluate peripheral nerve repair.

    Science.gov (United States)

    Wang, Dong; Huang, Xijun; Fu, Guo; Gu, Liqiang; Liu, Xiaolin; Wang, Honggang; Hu, Jun; Yi, Jianhua; Niu, Xiaofeng; Zhu, Qingtang

    2014-05-15

    Current research on bone marrow stem cell transplantation and autologous or xenogenic nerve transplantation for peripheral nerve regeneration has mainly focused on the repair of peripheral nerve defects in rodents. In this study, we established a standardized experimental model of radial nerve defects in primates and evaluated the effect of repair on peripheral nerve injury. We repaired 2.5-cm lesions in the radial nerve of rhesus monkeys by transplantation of autografts, acellular allografts, or acellular allografts seeded with autologous bone marrow stem cells. Five months after surgery, regenerated nerve tissue was assessed for function, electrophysiology, and histomorphometry. Postoperative functional recovery was evaluated by the wrist-extension test. Compared with the simple autografts, the acellular allografts and allografts seeded with bone marrow stem cells facilitated remarkable recovery of the wrist-extension functions in the rhesus monkeys. This functional improvement was coupled with radial nerve distal axon growth, a higher percentage of neuron survival, increased nerve fiber density and diameter, increased myelin sheath thickness, and increased nerve conduction velocities and peak amplitudes of compound motor action potentials. Furthermore, the quality of nerve regeneration in the bone marrow stem cells-laden allografts group was comparable to that achieved with autografts. The wrist-extension test is a simple behavioral method for objective quantification of peripheral nerve regeneration. PMID:25206757

  17. A simple model of radial nerve injury in the rhesus monkey to evaluate peripheral nerve repair

    Institute of Scientific and Technical Information of China (English)

    Dong Wang; Qingtang Zhu; Xijun Huang; Guo Fu; Liqiang Gu; Xiaolin Liu; Honggang Wang; Jun Hu; Jianhua Yi; Xiaofeng Niu

    2014-01-01

    Current research on bone marrow stem cell transplantation and autologous or xenogenic nerve transplantation for peripheral nerve regeneration has mainly focused on the repair of peripher-al nerve defects in rodents. In this study, we established a standardized experimental model of radial nerve defects in primates and evaluated the effect of repair on peripheral nerve injury. We repaired 2.5-cm lesions in the radial nerve of rhesus monkeys by transplantation of autografts, acellular allografts, or acellular allografts seeded with autologous bone marrow stem cells. Five months after surgery, regenerated nerve tissue was assessed for function, electrophysiology, and histomorphometry. Postoperative functional recovery was evaluated by the wrist-extension test. Compared with the simple autografts, the acellular allografts and allografts seeded with bone marrow stem cells facilitated remarkable recovery of the wrist-extension functions in the rhesus monkeys. This functional improvement was coupled with radial nerve distal axon growth, a higher percentage of neuron survival, increased nerve fiber density and diameter, increased myelin sheath thickness, and increased nerve conduction velocities and peak amplitudes of compound motor action potentials. Furthermore, the quality of nerve regeneration in the bone marrow stem cells-laden allografts group was comparable to that achieved with autografts. The wrist-extension test is a simple behavioral method for objective quantification of peripheral nerve regeneration.

  18. The Morphofunctional Effect of the Transplantation of Bone Marrow Stromal Cells and Predegenerated Peripheral Nerve in Chronic Paraplegic Rat Model via Spinal Cord Transection

    OpenAIRE

    Vinnitsa Buzoianu-Anguiano; Sandra Orozco-Suárez; Elisa García-Vences; Sara Caballero-Chacón; Gabriel Guizar-Sahagún; Luis Chavez-Sanchez; Israel Grijalva

    2015-01-01

    Functional recovery following spinal cord injury (SCI) is limited by poor axonal and cellular regeneration as well as the failure to replace damaged myelin. Employed separately, both the transplantation of the predegenerated peripheral nerve (PPN) and the transplantation of bone marrow stromal cells (BMSCs) have been shown to promote the regrowth and remyelination of the damaged central axons in SCI models of hemisection, transection, and contusion injury. With the aim to test the effects of ...

  19. Distribution of nitric oxide synthase, nerve growth factor receptor and interstitial cells of Cajal in hirschsprung s disease and its significance

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Objective To investigate the distribution of nitric oxide synthase (NOS), nerve growth factor receptor (NGFR) and interstitial cells of Cajal (ICCs) in Hirschsprung's disease (HD). Methods The distribution of NOS, NGFR and ICCs was studied by using NADPH diaphorase histochemistry, immunohistochemistry with a monoclonal antibody to human NGFR and the specific polyclonal antibody against c-kit in 8 normal controls and 10 cases of HD. Results NOS and NGFR were abundantly present in the myenteric plexus and in ...

  20. Medroxyprogesterone Acetate Modulates Remodeling, Immune Cell Census, and Nerve Fibers in the Cervix of a Mouse Model for Inflammation-induced Preterm Birth

    OpenAIRE

    Yellon, Steven M.; Ebner, Charlotte A.; Elovitz, Michal A.

    2008-01-01

    To determine whether a progestational agent can modify inflammation-induced preterm cervical ripening, mice on day 15 of gestation were given an intrauterine injection of (1) saline, (2) lipopolysaccharide, (3) an intramuscular injection of medroxyprogesterone acetate alone prior to lipopolysaccharide, or (4) medroxyprogesterone acetate alone. Cervices were obtained 6 hours later, then fixed, sectioned, and processed to stain collagen structure or to identify immune cells or nerve fibers. Cer...

  1. Demonstration of immunochemical identity between the nerve growth factor-inducible large external (NILE) glycoprotein and the cell adhesion molecule L1

    DEFF Research Database (Denmark)

    Bock, E; Richter-Landsberg, C; Faissner, A;

    1985-01-01

    The nerve growth factor-inducible large external (NILE) glycoprotein and the neural cell adhesion molecule L1 were shown to be immunochemically identical. Immunoprecipitation with L1 and NILE antibodies of [3H]fucose-labeled material from culture supernatants and detergent extracts of NGF......]methionine-labeled early post-natal cerebellar cell cultures or [3H]fucose-labeled NGF-treated PC12 cells, all immunoreactivity for NILE antibody could be removed by pre-clearing with L1 antibody and vice versa....

  2. Schwannomatosis of the sciatic nerve

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Tetsuji; Maruyama, Shigeki; Mizuno, Kosaku [Dept. of Orthopaedic Surgery, Kobe University School of Medicine (Japan)

    2001-02-01

    A 52-year-old woman with schwannomatosis in the left sciatic nerve is presented. The patient had no stigmata of neurofibromatosis (NF) type 1 or 2. Cutaneous or spinal schwannomas were not detected. Magnetic resonance (MR) imaging of the sciatic nerve revealed more than 15 tumors along the course of the nerve. Histological examination revealed schwannomas consisting of Antoni A and B areas. Immunohistochemical study showed most cells reacting intensely for S-100 protein. The patient underwent conservative follow-up treatment due to the minimal symptoms. The relationship of the disease with NF-2 and plexiform schwannoma is discussed. (orig.)

  3. elPBN neurons regulate rVLM activity through elPBN-rVLM projections during activation of cardiac sympathetic afferent nerves.

    Science.gov (United States)

    Guo, Zhi-Ling; Longhurst, John C; Tjen-A-Looi, Stephanie C; Fu, Liang-Wu

    2016-08-01

    The external lateral parabrachial nucleus (elPBN) within the pons and rostral ventrolateral medulla (rVLM) contributes to central processing of excitatory cardiovascular reflexes during stimulation of cardiac sympathetic afferent nerves (CSAN). However, the importance of elPBN cardiovascular neurons in regulation of rVLM activity during CSAN activation remains unclear. We hypothesized that CSAN stimulation excites the elPBN cardiovascular neurons and, in turn, increases rVLM activity through elPBN-rVLM projections. Compared with controls, in rats subjected to microinjection of retrograde tracer into the rVLM, the numbers of elPBN neurons double-labeled with c-Fos (an immediate early gene) and the tracer were increased after CSAN stimulation (P stimulation of CSAN increased the activity of elPBN cardiovascular neurons, which was attenuated (n = 6, P stimulation (n = 5, P stimulation activates cardiovascular neurons in the elPBN and rVLM sequentially through a monosynaptic (glutamatergic) excitatory elPBN-rVLM pathway. PMID:27225950

  4. Size of the Optic Nerve Head and Its Relationship with the Thickness of the Macular Ganglion Cell Complex and Peripapillary Retinal Nerve Fiber Layer in Patients with Primary Open Angle Glaucoma

    Directory of Open Access Journals (Sweden)

    Nobuko Enomoto

    2015-01-01

    Full Text Available Purpose. To evaluate the relationships among the optic nerve head (ONH area, macular ganglion cell complex (mGCC thickness, circumpapillary retinal nerve fiber layer (cpRNFL thickness, and visual field defects in patients with primary open angle glaucoma (POAG. Methods. This retrospective study included 90 eyes of 90 patients with POAG. The ONH area, rim area, mGCC thickness, and cpRNFL thickness were measured using optical coherence tomography. Mean deviation (MD was measured using standard automated perimetry. The relationships among clinical factors including age, refraction, the ONH area, the rim area, the mGCC thickness, the cpRNFL thickness, and MD were evaluated using correlation coefficients and multiple regression analyses. Results. The significant correlation of the ONH area with refraction (r=0.362, P<0.001, the mGCC thickness (r=0.225, P=0.033, and the cpRNFL thickness (r=0.253, P=0.016 was found. Multiple regression analysis showed that the ONH area, rim area, and MD were selected as significant contributing factors to explain the mGCC thickness and cpRNFL thickness. No factor was selected to explain MD. Conclusions. The ONH area, in other words, the disc size itself may affect the mGCC thickness and cpRNFL thickness in POAG patients.

  5. Electroacupuncture-Induced Cholinergic Nerve Activation Enhances the Hypoglycemic Effect of Exogenous Insulin in a Rat Model of Streptozotocin-Induced Diabetes

    Directory of Open Access Journals (Sweden)

    Yu-Chen Lee

    2011-01-01

    Full Text Available The aim of this study is to explore the mechanisms by which electroacupuncture (EA enhances the hypoglycemic effect of exogenous insulin in a streptozotocin- (STZ- diabetic rats. Animals in the EA group were anesthetized and subjected to the insulin challenge test (ICT and EA for 60 minutes. In the control group, rats were subjected to the same treatment with the exception of EA stimulation. Blood samples were drawn to measure changes in plasma glucose, free fatty acids (FFA, and insulin levels. Western blot was used to assay proteins involved in insulin signaling. Furthermore, atropine, hemicholinium-3 (HC-3, and Eserine were used to explore the relationship between EA and cholinergic nerve activation during ICT. EA augmented the blood glucose-lowering effects of EA by activating the cholinergic nerves in STZ rats that had been exposed to exogenous insulin. This phenomenon may be related to enhancement of insulin signaling rather than to changes in FFA concentration.

  6. Changes in baroreflex control of renal sympathetic nerve activity in high-fat-fed rats as a predictor of hypertension.

    Science.gov (United States)

    Fardin, Núbia M; Oyama, Lila M; Campos, Ruy R

    2012-08-01

    There is evidence that obesity is associated with increased sympathetic activity and hypertension. However, the mechanisms responsible for these changes are not fully understood. Therefore, the aim of the present study was to evaluate the cardiovascular function and the baroreceptor reflex control of renal sympathetic nerve activity (rSNA) in rats exposed to a high-fat diet over different periods (10 and 20 weeks) compared to control rats. Serum leptin levels were assessed for all time points. Male Wistar rats weighing 150-180 g were used. Four groups of rats were studied: control 10 weeks (Ct10), obese 10 weeks (Ob10), control 20 weeks (Ct20), and obese 20 weeks (Ob20). Blood pressure (BP) and rSNA were recorded in urethane-anesthetized rats (1.4 g/kg, intravenous).The sensitivity of rSNA responses to baroreceptor reflex was assessed by changes in BP induced by increasing doses of phenylephrine or sodium nitroprusside. Significant and progressive increases in serum leptin levels were found in the obese rats, but not in the control rats. No changes in basal BP or rSNA were found in the Ob10 and Ob20 groups; however, a significant impairment in the baroreceptor sensitivity was observed in the Ob20 group for phenylephrine (slope Ob20: -0.78 ± 0.12 vs. Ct20: -1.00 ± 0.08 potential per second (pps)/mm Hg, P sodium nitroprusside (slope Ob20: -0.82 ± 0.09 vs. 1.13 ± 0.13 pps/mm Hg, P < 0.05). The results suggest that the baroreceptor dysfunction that controls the rSNA is an initial change in the obesity induced in high-fat-fed rats, which might be a predictor of sympathoexcitation and hypertension associated to obesity. PMID:22257982

  7. Region-specific changes in sympathetic nerve activity in angiotensin II-salt hypertension in the rat.

    Science.gov (United States)

    Osborn, John W; Fink, Gregory D

    2010-01-01

    It is now well accepted that many forms of experimental hypertension and human essential hypertension are caused by increased activity of the sympathetic nervous system. However, the role of region-specific changes in sympathetic nerve activity (SNA) in the pathogenesis of hypertension has been difficult to determine because methods for chronic measurement of SNA in conscious animals have not been available. We have recently combined indirect, and continuous and chronic direct, assessment of region-specific SNA to characterize hypertension produced by administration of angiotensin II (Ang II) to rats consuming a high-salt diet (Ang II-salt hypertension). Angiotensin II increases whole-body noradrenaline (NA) spillover and depressor responses to ganglionic blockade in rats consuming a high-salt diet, but not in rats on a normal-salt diet. Despite this evidence for increased 'whole-body SNA' in Ang II-salt hypertensive rats, renal SNA is decreased in this model and renal denervation does not attenuate the steady-state level of arterial pressure. In addition, neither lumbar SNA, which largely targets skeletal muscle, nor hindlimb NA spillover is changed from control levels in Ang II-salt hypertensive rats. However, surgical denervation of the splanchnic vascular bed attenuates/abolishes the increase in arterial pressure and total peripheral resistance, as well as the decrease in vascular capacitance, observed in Ang II-salt hypertensive rats. We hypothesize that the 'sympathetic signature' of Ang II-salt hypertension is characterized by increased splanchnic SNA, no change in skeletal muscle SNA and decreased renal SNA, and this sympathetic signature creates unique haemodynamic changes capable of producing sustained hypertension. PMID:19717492

  8. Effect of cortisol on muscle sympathetic nerve activity in Pima Indians and Caucasians

    DEFF Research Database (Denmark)

    Vozarova, Barbora; Weyer, Christian; Snitker, Soren;

    2003-01-01

    . Although glucocorticoids inhibit SNS activity, Pima Indians are not hypercortisolemic compared with Caucasians. This does not exclude the possibility that the SNS is more responsive to an inhibitory effect of cortisol in the former than in the latter group. We measured fasting plasma ACTH and cortisol...... (metyrapone) followed by cortisol replacement (hydrocortisone) on plasma ACTH, cortisol, and MSNA. There were no ethnic differences in fasting plasma ACTH or cortisol, but MSNA adjusted for percent body fat was lower in Pimas than in Caucasians (P cortisol...... to a tonic inhibitory effect of cortisol. However, an acute release of cortisol is likely to more effectively contain sympathoexcitation during stress in Pima Indians than in Caucasians, which may be an important mechanism of cardioprotection in this Native American population....

  9. Sciatic nerve regeneration using a nerve growth factor-containing fibrin glue membrane

    Institute of Scientific and Technical Information of China (English)

    Shengzhong Ma; Changliang Peng; Shiqing Wu; Dongjin Wu; Chunzheng Gao

    2013-01-01

    Our previous findings confirmed that the nerve growth factor-containing fibrin glue membrane pro-vides a good microenvironment for peripheral nerve regeneration;however, the precise mechanism remains unclear. p75 neurotrophin receptor (p75NTR) plays an important role in the regulation of pe-ripheral nerve regeneration. We hypothesized that a nerve growth factor-containing fibrin glue membrane can promote neural regeneration by up-regulating p75NTR expression. In this study, we used a silicon nerve conduit to bridge a 15 mm-long sciatic nerve defect and injected a mixture of nerve growth factor and fibrin glue at the anastomotic site of the nerve conduit and the sciatic nerve. Through RT-PCR and western blot analysis, nerve growth factor-containing fibrin glue membrane significantly increased p75NTR mRNA and protein expression in the Schwann cells at the anasto-motic site, in particular at 8 weeks after injection of the nerve growth factor/fibrin glue mixture. These results indicate that nerve growth factor-containing fibrin glue membrane can promote pe-ripheral nerve regeneration by up-regulating p75NTR expression in Schwann cells.

  10. Promoting Nerve Regeneration in a Neurotmesis Rat Model Using Poly(DL-lactide-ε-caprolactone Membranes and Mesenchymal Stem Cells from the Wharton’s Jelly: In Vitro and In Vivo Analysis

    Directory of Open Access Journals (Sweden)

    T. Pereira

    2014-01-01

    Full Text Available In peripheral nerves MSCs can modulate Wallerian degeneration and the overall regenerative response by acting through paracrine mechanisms directly on regenerating axons or upon the nerve-supporting Schwann cells. In the present study, the effect of human MSCs from Wharton’s jelly (HMSCs, differentiated into neuroglial-like cells associated to poly (DL-lactide-ε-caprolactone membrane, on nerve regeneration, was evaluated in the neurotmesis injury rat sciatic nerve model. Results in vitro showed successful differentiation of HMSCs into neuroglial-like cells, characterized by expression of specific neuroglial markers confirmed by immunocytochemistry and by RT-PCR and qPCR targeting specific genes expressed. In vivo testing evaluated during the healing period of 20 weeks, showed no evident positive effect of HMSCs or neuroglial-like cell enrichment at the sciatic nerve repair site on most of the functional and nerve morphometric predictors of nerve regeneration although the nociception function was almost normal. EPT on the other hand, recovered significantly better after HMSCs enriched membrane employment, to values of residual functional impairment compared to other treated groups. When the neurotmesis injury can be surgically reconstructed with an end-to-end suture or by grafting, the addition of a PLC membrane associated with HMSCs seems to bring significant advantage, especially concerning the motor function recovery.

  11. Taurolidine and congeners activate hTRPA1 but not hTRPV1 channels and stimulate CGRP release from mouse tracheal sensory nerves.

    Science.gov (United States)

    Kichko, Tatjana I; Pfirrmann, Rolf W; Reeh, Peter W

    2016-02-01

    Taurolidine has long been in clinical use as an antimicrobial irrigation that does not impede wound healing. It can even be administered intravenously (30 g/day) to treat sepsis or to exert newly recognized antineoplastic actions. Only one irritant effect is reported, that is, to temporarily induce burning pain of unknown origin when applied to body cavities or peripheral veins. The structure of the molecule suggested the chemoreceptor channel TRPA1 as a potential target, which was verified measuring stimulated CGRP release from sensory nerves of the isolated mouse trachea and calcium influx in hTRPA1-transfected HEK293 cells. With both methods, the concentration-response relationship of taurolidine exceeded the threshold value below 500 μmol/L and 100 μmol/L, respectively, and reached saturation at 1 mmol/L. The clinical 2% taurolidine solution did not evoke greater or longer lasting responses. The reversible tracheal response was abolished in TRPA1(-/-) but retained in TRPV1(-/-) mice. Consistently, hTRPV1-HEK showed no calcium influx as a response, likewise native HEK293 cells and hTRPA1-HEK deprived of extracellular calcium did not respond to taurolidine 1 mmol/L. The metabolite taurultam and its oxathiazine derivative, expected to cause less burning pain, showed weak tracheal irritancy only at 10 mmol/L, acting also through hTRPA1 but not hTRPV1. In conclusion, taurolidine, its metabolite, and a novel derivative showed no unspecific cellular effects but selectively, concentration-dependently and reversibly activated the irritant receptor TRPA1 in CGRP-expressing, thus nociceptive, neurons. The clinical solution of 2% taurolidine (~70 mmol/L) can, thus, rightly be expected to cause transient burning pain and neurogenic inflammation. PMID:26977296

  12. Substance P combined with epidermal stem cells promotes wound healing and nerve regeneration in diabetes mellitus

    OpenAIRE

    Fei-bin Zhu; Xiang-jing Fang; De-wu Liu; Ying Shao; Hong-yan Zhang; Yan Peng; Qing-ling Zhong; Yong-tie Li; De-ming Liu

    2016-01-01

    Exogenous substance P accelerates wound healing in diabetes, but the mechanism remains poorly understood. Here, we established a rat model by intraperitoneally injecting streptozotocin. Four wounds (1.8 cm diameter) were drilled using a self-made punch onto the back, bilateral to the vertebral column, and then treated using amniotic membrane with epidermal stem cells and/or substance P around and in the middle of the wounds. With the combined treatment the wound-healing rate was 100% at 14 da...

  13. Experimental study of acellular nerve and adipose derived stem cells in repairing of nerve defects%去细胞神经复合脂肪干细胞修复神经缺损的实验研究

    Institute of Scientific and Technical Information of China (English)

    高嵩涛; 蔡启卿; 姚伟涛; 王家强; 王鑫; 张鹏

    2015-01-01

    异体神经构建的组织工程化神经能有效地修复大鼠坐骨神经缺损。%Objective To investigate the efficacy of allogenic acellular nerve scaffold and adipose derived stem cells (ADSCs)⁃differentiated Schwann⁃like in repairing the sciatic nerve defect of rats. Methods Thirty healthy F344 inbred rats were randomly divided into two groups (n=15 each). In these groups,a 10⁃mm sciatic nerve defect was bridged with different grafts:allogenic acellular nerve(from SD rat)scaffold in Group A,and allogenic acellular nerve scaffold seeded with Schwann⁃like cells differentiated from ADSCs in Group B. After 6 and 12 weeks,the both groups were compared for recovery rate of sciatic functional index (SFI%) and the neural electrophysiology (NEP) which included recovery rates of motor nerve conduction velocity (MNCV) of sciatic nerve, compound muscle action potential (CAMP) of gastrocnemius,regenerated myelinated fiber counts,nerve fiber diameter and myelin sheath thickness,as well as histological changes with myelin regeneration under light microscopy and transmission electron microscopy,so as to evaluate the experimental efficacy. Results At 6 and 12 weeks after operation,the Group B appeared advantageous over Group A in SFI%(at 6 weeks,52.38 ± 7.12 vs 46.32 ± 5.13;at 12 weeks,79.99 ± 10.33 vs 72.73 ± 8.06),MNCV recovery rate(at 6 weeks,51.12 ± 8.15 vs 42.54 ± 6.33;at12 weeks,75.93 ± 5.95 vs 69.34 ± 9.13),CAMP recovery rate(at 6 weeks,45.38 ± 4.12 vs 40.52 ± 4.15;at 12 weeks,75.98 ± 10.99 vs 68.24 ± 9.45),regenerated myelinated nerve fiber count recovery rate(at 6 weeks, 44.29±7.52 vs 38.45±6.28;at 12 weeks,77.06±11.54 vs 67.89±11.87),nerve fiber diameter recovery rate (at 6 weeks,43.58 ± 4.87 vs 40.11 ± 4.32;at 12 weeks,83.23 ± 6.32 vs 76.37 ± 9.38),myelin sheath thickness recovery rate(at 6 weeks,46.41±4.35 vs 41.33±4.58;at 12 weeks,83.96±8.31 vs 77.62±7.98) (all P<0.05). Light microscopy revealed that the diameter and number of

  14. Effects of three days of dry immersion on muscle sympathetic nerve activity and arterial blood pressure in humans.

    Science.gov (United States)

    Iwase, S; Sugiyama, Y; Miwa, C; Kamiya, A; Mano, T; Ohira, Y; Shenkman, B; Egorov, A I; Kozlovskaya, I B

    2000-03-15

    The present study was performed to determine how sympathetic function is altered by simulated microgravity, dry immersion for 3 days, and to elucidate the mechanism of post-spaceflight orthostatic intolerance in humans. Six healthy men aged 21-36 years old participated in the study. Before and after the dry immersion, subjects performed head-up tilt (HUT) test to 30 degrees and 60 degrees (5 min each) with recordings of muscle sympathetic nerve activity (MSNA, by microneurography), electrocardiogram, and arterial blood pressure (Finapres). Resting MSNA was increased after dry immersion from 23.7+/-3.2 to 40.9+/-3.0 bursts/min (p<0.005) without significant changes in resting heart rate (HR). MSNA responsiveness to orthostasis showed no significant difference but HR response was significantly augmented after dry immersion (p<0. 005). A significant diastolic blood pressure fall at 5th min of 60 degrees HUT was observed in five orthostatic tolerant subjects despite enough MSNA discharge after dry immersion. A subject suffered from presyncope at 2 min after 60 degrees HUT. He showed gradual blood pressure fall 10 s after 60 degrees HUT with initially well-maintained MSNA response and then with a gradually attenuated MSNA, followed by a sudden MSNA withdrawal and abrupt blood pressure drop. In conclusion, dry immersion increased MSNA without changing MSNA response to orthostasis, and resting HR, while increasing the HR response to orthostasis. Analyses of MSNA and blood pressure changes in orthostatic tolerant subjects and a subject with presyncope suggested that not only insufficient vasoconstriction to sympathetic stimuli, but also a central mechanism to induce a sympathetic withdrawal might play a role in the development of orthostatic intolerance after microgravity exposure.

  15. Arterial baroreceptor reflex control of renal sympathetic nerve activity following chronic myocardial infarction in male, female, and ovariectomized female rats.

    Science.gov (United States)

    Pinkham, Maximilian I; Whalley, Gillian A; Guild, Sarah-Jane; Malpas, Simon C; Barrett, Carolyn J

    2015-07-15

    There is controversy regarding whether the arterial baroreflex control of renal sympathetic nerve activity (SNA) in heart failure is altered. We investigated the impact of sex and ovarian hormones on changes in the arterial baroreflex control of renal SNA following a chronic myocardial infarction (MI). Renal SNA and arterial pressure were recorded in chloralose-urethane anesthetized male, female, and ovariectomized female (OVX) Wistar rats 6-7 wk postsham or MI surgery. Animals were grouped according to MI size (sham, small and large MI). Ovary-intact females had a lower mortality rate post-MI (24%) compared with both males (38%) and OVX (50%) (P < 0.05). Males and OVX with large MI, but not small MI, displayed an impaired ability of the arterial baroreflex to inhibit renal SNA. As a result, the male large MI group (49 ± 6 vs. 84 ± 5% in male sham group) and OVX large MI group (37 ± 3 vs. 75 ± 5% in OVX sham group) displayed significantly reduced arterial baroreflex range of control of normalized renal SNA (P < 0.05). In ovary-intact females, arterial baroreflex control of normalized renal SNA was unchanged regardless of MI size. In males and OVX there was a significant, positive correlation between left ventricle (LV) ejection fraction and arterial baroreflex range of control of normalized renal SNA, but not absolute renal SNA, that was not evident in ovary-intact females. The current findings demonstrate that the arterial baroreflex control of renal SNA post-MI is preserved in ovary-intact females, and the state of left ventricular dysfunction significantly impacts on the changes in the arterial baroreflex post-MI. PMID:25994953

  16. Catheter Ablation of Atrial Fibrillation Raises the Plasma Level of NGF-β Which Is Associated with Sympathetic Nerve Activity

    OpenAIRE

    Park, Jae Hyung; Hong, Sung Yu; Wi, Jin; Lee, Da Lyung; Joung, Boyoung; Lee, Moon Hyoung; Pak, Hui-Nam

    2015-01-01

    Purpose The expression of nerve growth factor-β (NGF-β) is related to cardiac nerve sprouting and sympathetic hyper innervation. We investigated the changes of plasma levels of NGF-β and the relationship to follow-up heart rate variability (HRV) after radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF). Materials and Methods This study included 147 patients with AF (117 men, 55.8±11.5 years, 106 paroxysmal AF) who underwent RFCA. The plasma levels of NGF-β were quantified usin...

  17. Microarray and synchronization of neuronal differentiation with pathway changes in the Kyoto Encyclopedia of Genes and Genomes (KEGG) databank in nerve growth factor-treated PC12 cells.

    Science.gov (United States)

    Lin, Chih-Ming; Feng, Wayne

    2012-08-01

    The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway database creates networks from interrelations between molecular biology and underlying chemical elements. This allows for analysis of biologic networks, genomic information, and higher-order functional information at a systems level. We performed microarray experiments and used the KEGG database, systems biology analysis, and annotation of pathway function to study nerve growth factor (NGF)-induced differentiation of PC12 cells. Cells were cultured to 70%-80% confluence, treated with NGF for 1 or 3 hours (h), and RNA was extracted. Stage 1 data analysis involved analysis of variance (ANOVA), and stage 2 involved cluster analysis and heat map generation. We identified 2020 NGF-induced PC12 genes (1038 at 1 h and 1554 at 3 h). Results showed changes in gene expression over time. We compared these genes with 6035 genes from the KEGG database. Cross-matching resulted in 830 genes. Among these, we identified 395 altered genes (155 at 1 h and 301 at 3 h; 2-fold increase from 1 h to 3 h). We identified 191 biologic pathways in the KEGG database; the top 15 showed correlations with neuronal differentiation (mitogen-activated protein kinase [MAPK] pathway: 35 genes at 1 h, 54 genes at 3 h; genes associated with axonal guidance: 12 at 1 h, 26 at 3 h; Wnt pathway: 16 at 1 h, 25 at 3 h; neurotrophin pathway: 4 at 1 h, 14 at 3 h). Thus, we identified changes in neuronal differentiation pathways with the KEGG database, which were synchronized with NGF-induced differentiation.

  18. Improving the Catalytic Activity of Hyperthermophilic Pyrococcus horikoshii Prolidase for Detoxification of Organophosphorus Nerve Agents over a Broad Range of Temperatures

    Directory of Open Access Journals (Sweden)

    Casey M. Theriot

    2011-01-01

    Full Text Available Prolidases hydrolyze Xaa-Pro dipeptides and can also cleave the P-F and P-O bonds found in organophosphorus (OP compounds, including the nerve agents soman and sarin. Ph1prol (PH0974 has previously been isolated and characterized from Pyrococcus horikoshii and was shown to have higher catalytic activity over a broader pH range, higher affinity for metal, and increased thermostability compared to P. furiosus prolidase, Pfprol (PF1343. To obtain a better enzyme for OP nerve agent decontamination and to investigate the structural factors that may influence protein thermostability and thermoactivity, randomly mutated Ph1prol enzymes were prepared. Four Ph1prol mutants (A195T/G306S-, Y301C/K342N-, E127G/E252D-, and E36V-Ph1prol were isolated which had greater thermostability and improved activity over a broader range of temperatures against Xaa-Pro dipeptides and OP nerve agents compared to wild type Pyrococcus prolidases.

  19. The involvement of NF-κB in PDT-induced death of crayfish glial and nerve cells

    Science.gov (United States)

    Berezhnaya, E. V.; Neginskaya, M. A.; Kovaleva, V. D.; Rudkovskii, M. V.; Uzdensky, A. B.

    2015-03-01

    Photodynamic therapy (PDT) is used for selective destruction of cells, in particular, for treatment of brain tumors. However, photodynamic treatment damages not only tumor cells, but also healthy neurons and glial cells. To study the possible role of NF-κB in photodynamic injury of neurons and glial cells, we investigated the combined effect of photodynamic treatment and NF-κB modulators: activator betulinic acid, or inhibitors parthenolide and CAPE on an isolated crayfish stretch receptor consisting of a single neuron surrounded by glial cells. A laser diode (670 nm, 0.4 W/cm2) was used as a light source. The inhibition of NF-κB during PDT increased the duration of neuron firing and glial necrosis and decreased neuron necrosis and glial apoptosis. The activation of NF-κB during PDT increased neuron necrosis and glial apoptosis and decreased glial necrosis. The difference between the effects of NF-κB modulators on photosensitized neurons and glial cells indicates the difference in NF-κB-mediated signaling pathways in these cell types. Thus, NF-κB is involved in PDT-induced shortening of neuron firing, neuronal and glial necrosis, and apoptosis of glial cells.

  20. Effects of nerve growth factor and heart cell conditioned medium on neurite regeneration of aged sympathetic neurons in culture.

    Science.gov (United States)

    Uchida, Y; Tomonaga, M

    1985-11-25

    The effects of nerve growth factor (NGF) and heart-cell-conditioned medium (HCM) on the neurite regeneration of aged sympathetic neurons were investigated in culture. Investigation of HCM was carried out by two different methods: one was the use of whole HCM on collagen substratum, which reflected component(s) effective in solution (HCM-S); the other was the use of polyornithine (PORN)-binding component(s) (P-HCM). Superior cervical ganglion neurons prepared from male mice from 6 to 30 months of age were cultured in MEM-10% FCS on collagen or gelatin-PORN substratum for 3 days. The number of neurons with neurites and the length of neurites were quantified as neurite production and elongation, respectively. Neuronal survival was not affected by addition of NGF, HCM-S or P-HCM. Neurite production of early adult neurons was enhanced by NGF, HCM-S or P-HCM. In contrast, neurite production of aged neurons was enhanced by only HCM-S, but not NGF or P-HCM. HCM-S did not promote neurite elongation in neurons at any age. Neurite elongation of early adult neurons was enhanced by NGF or P-HCM. Neurite elongation of aged neurons was enhanced by P-HCM. However, responsiveness of NGF for neurite elongation varied according to substrata. No age-related difference was found in neurite production and elongation in the absence of NGF, HCM-S or P-HCM. These results indicate that responsiveness of aged sympathetic neurons is various in different growth factors. PMID:3840716

  1. IL-10 and NOS2 modulate antigen-specific reactivity and nerve infiltration by T cells in experimental leprosy.

    Directory of Open Access Journals (Sweden)

    Deanna A Hagge

    2014-09-01

    Full Text Available Although immunopathology dictates clinical outcome in leprosy, the dynamics of early and chronic infection are poorly defined. In the tuberculoid region of the spectrum, Mycobacterium leprae growth is restricted yet a severe granulomatous lesion can occur. The evolution and maintenance of chronic inflammatory processes like those observed in the leprosy granuloma involve an ongoing network of communications via cytokines. IL-10 has immunosuppressive properties and IL-10 genetic variants have been associated with leprosy development and reactions.The role of IL-10 in resistance and inflammation in leprosy was investigated using Mycobacterium leprae infection of mice deficient in IL-10 (IL-10-/-, as well as mice deficient in both inducible nitric oxide synthase (NOS2-/- and IL-10 (10NOS2-/-. Although a lack of IL-10 did not affect M. leprae multiplication in the footpads (FP, inflammation increased from C57Bl/6 (B6cells responding to M. leprae cell wall, membrane, and cytosol antigens and ML2028 (Ag85B were significantly increased in the evolved granuloma in NOS2-/- FP compared to B6 and IL-10-/- during early and peak phases. In 10NOS2-/- FP, CD4+CD44+ and especially CD8+CD44+ responses were augmented even further to these antigens as well as to ML0380 (GroES, ML2038 (bacterioferritin, and ML1877 (EF-Tu. Moreover, fragmented nerves containing CD4+ cells were present in 10NOS2-/- FP.The 10NOS2-/- strain offers insight on the regulation of granuloma formation and maintenance by immune modulators in the resistant forms of leprosy and presents a new model for investigating the pathogenesis of neurological involvement.

  2. Upregulated gene expression of local brain-derived neurotrophic factor and nerve growth factor after intracisternal administration of marrow stromal cells in rats with traumatic brain injury

    Institute of Scientific and Technical Information of China (English)

    胡德志; 周良辅; 朱剑虹; 毛颖; 吴雪海

    2005-01-01

    Objective: To examine the effects of rat marrow stromal cells (rMSCs) on gene expression of local brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) after injection of rMSCs into Cistern Magnum of adult rats subjected to traumatic brain injury(TBI).Results: Group cell transplantation had higher BDNF and NGF gene expressions than Group saline control during a period of less than 3 weeks (P<0.05).Conclusions: rMSCs transplantation via Cistern Magnum in rats subjected to traumatic brain injury can enhance expressions of local brain NGF and BDNF to a certain extent.

  3. Transcompartmental reversal of single fibre hyperexcitability in juxtaparanodal Kv1.1-deficient vagus nerve axons by activation of nodal KCNQ channels.

    Science.gov (United States)

    Glasscock, Edward; Qian, Jing; Kole, Matthew J; Noebels, Jeffrey L

    2012-08-15

    Kv1.1 channels cluster at juxtaparanodes of myelinated axons in the vagus nerve, the primary conduit for parasympathetic innervation of the heart. Kcna1-null mice lacking these channels exhibit neurocardiac dysfunction manifested by atropine-sensitive atrioventricular conduction blocks and bradycardia that may culminate in sudden death. To evaluate whether loss of Kv1.1 channels alters electrogenic properties within the nerve, we compared the intrinsic excitability of single myelinated A- and Aδ-axons from excised cervical vagus nerves of young adult Kcna1-null mice and age-matched, wild-type littermate controls. Although action potential shapes and relative refractory periods varied little between genotypes, Kv1.1-deficient large myelinated A-axons showed a fivefold increase in susceptibility to 4-aminopyridine (4-AP)-induced spontaneous ectopic firing. Since the repolarizing currents of juxtaparanodal Kv1 channels and nodal KCNQ potassium channels both act to dampen repetitive activity, we examined whether augmenting nodal KCNQ activation could compensate for Kv1.1 loss and reverse the spontaneous hyperexcitability in Kv1.1-deficient A-axons. Application of the selective KCNQ opener flupirtine raised A-axon firing threshold while profoundly suppressing 4-AP-induced spontaneous firing, demonstrating a functional synergy between the two compartments. We conclude that juxtaparanodal Kv1.1-deficiency causes intrinsic hyperexcitability in large myelinated axons in vagus nerve which could contribute to autonomic dysfunction in Kcna1-null mice, and that KCNQ openers reveal a transcompartmental synergy between Kv1 and KCNQ channels in regulating axonal excitability. PMID:22641786

  4. Breathing Pattern and Lung Mechanics during Assisted Ventilation Response of Slowly Adapting Pulmonary Stretch Receptors and Effects on Phrenic Nerve Activity in Cats with Normal and Surfactant Depleted Lungs

    OpenAIRE

    Sindelar, Richard

    2001-01-01

    Different modes of assisted ventilation were investigated in cats before and after lung lavage and after instillation of surfactant. The activity of single units of slowly adapting pulmonary stretch receptors (PSRs) in the vagal nerve and the integrated phrenic nerve activity were recorded. The instantaneous impulse frequency (fimp) of PSRs was calculated and related to transpulmonary pressure (Ptp), tidal volume (Vt) and the calculated energy storage of the lung (ΣP*ΔV). Respiratory rate (RR...

  5. Chitosan Conduit for Peripheral Nerve Regeneration

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Chitosan, the N-deacetylated form of chitin, has good biocompatibility and biodegradability.This paper investigates the feasibility of using chitosan conduits for peripheral nerve regeneration.Cell culture experiments were used to test the material's cytotoxicity and affinity to nerve cells.Conduit implantation experiments were used to study the degradation of the material and the regeneration of injured sciatic nerves.The primary results indicate that chitosan has good mechanical properties, biocompatibility, and biodegradability and it may be a promising biomaterial for peripheral nerve regeneration.

  6. Polymeric Nerve Conduits with Contact Guidance Cues Used in Nerve Repair

    Institute of Scientific and Technical Information of China (English)

    G DAI; X NIU; J YIN

    2016-01-01

    In the modern life, the nerve injury frequently happens due to mechanical, chemical or thermal accidents. In the trivial injuries, the peripheral nerves can regenerate on their own; however, in most of the cases the clinical treatments are required, where relatively large nerve injury gaps are formed. Currently, the nerve repair can be accomplished by direct suture when the injury gap is not too large;while the autologous nerve graft working as the gold standard of peripheral nerve injury treatment for nerve injuries with larger gaps. However, the direct suture is limited by heavy tension at the suture sites, and the autologous nerve graft also has the drawbacks of donor site morbidity and insufifcient donor tissue. Recently, artiifcial nerve conduits have been developed as an alternative for clinical nerve repair to overcome the limitations associated with the above treatments. In order to further improve the efifciency of nerve conduits, various guidance cues are incorporated, including physical cues, biochemical signals, as well as support cells. First, this paper reviewed the contact guidance cues applied in nerve conduits, such as lumen ifllers, multi-channels and micro-patterns on the inner surface. Then, the paper focused on the polymeric nerve conduits with micro inner grooves. The polymeric nerve conduits were fabricated using the phase inversion-based ifber spinning techniques. The smart spinneret with grooved die was designed in the spinning platform, while different spinning conditions, including flow rates, air-gap distances, and polymer concentrations, were adjusted to investigate the inlfuence of fabrication conditions on the geometry of nerve conduits. The inner groove size in the nerve conduits can be precisely controlled in our hollow ifber spinning process, which can work as the efifcient contact guidance cue for nerve regeneration.

  7. Relevance of Memory Information and Inherent Frequency of Nerve Cells%记忆信息与大脑神经元固有频率的关联性

    Institute of Scientific and Technical Information of China (English)

    钟振余

    2016-01-01

    大脑记忆按事件方式储存,每个树突的固有频率就是记忆事件应有的信息元素.神经元表面成千上万个不同形态的树突树树棘所代表的信息集合就是一个记忆事件的信息储存总和.不同类型的信息内容储存在不同的脑区,同一瞬间储存在不同脑区的事件信息,通过突触机制关联成一个整体事件.记忆的读取遵循电波的谐振原理,通过突触关联的记忆电波可让肌体感知到类同于初始意识体验时曾经有过的意识状态.神经元的生存必须以稳定为前提,神经元不可以成为外来信息的传导介质,所以,颅内神经元群之间的信息交换只能以电波传播为主.%This paper aims to examine the information elements of a memory event to be stored in thousands of thorns of varied dendrites in the surface of nerve cells in different blocks of the brain in the sense of all the natural solid objects characteristic of inherent frequency. The elements memorized at the same time can be linked by synapses to a complete event, and the electric memory wave linked in the activated synapses in resonance enables the muscular motor to perceive the similar state of initial conscious experience. The traditional view suggested that signals ignited by the neurons encoded first in the lower nerve system, and then transmitted to the processing system of higher hierarchy to shape consciousness. In contrast, nerve cells couldn't be transmitters since they were assumed to exist in a stable condition. The transmission of information among the cell clusters were mainly conducted by electric wave, assisted by nerve fibers that work as an alarm and trigger of the transmission.

  8. Quantification of Oligodendrocyte Progenitor Cells in Human and Cat Optic Nerve:Implications for Endogenous Repair in Multiple Sclerosis

    Institute of Scientific and Technical Information of China (English)

    ALISON JENNINGS; WILLIAM CARROLL

    2010-01-01

    促进来源于少突胶质祖细胞(OP)的少突胶质细胞髓鞘再生,提高内源性修复是改善多发性硬化运动障碍的重要方法之一,其重要前提是明确人类中枢神经系统中有丰富的可分化为少突胶质细胞的OP细胞,而这需要有对中枢神经系统中的OP细胞进行鉴定的可靠方法.本研究采用多种方法对猫和人的视神经进行染色,根据相关结果获取可用于研究人尸体解剖标本OP细胞表达的抗原表型.OP细胞又被称为NG2细胞,广泛表达NG2蛋白,属于一个独立的胶质细胞亚型,由于其表达OP细胞系的转录因子Olig1和Olig2,因此与少突胶质细胞相关.虽然NG2细胞形态多样,与轴索及其它胶质细胞紧密联系,但所有NG2细胞都可以作为OP细胞进行分化,补充局部丢失的少突胶质细胞.研究发现,在人和猫的视神经及猫脊髓的白质和灰质中,NG2细胞在神经胶质细胞中所占比例不足5%,与少突胶质细胞的比例为1∶10.本研究结果显示,NG2细胞数量特别是相对少突胶质细胞不充足,这可对促进多发硬化内源性修复的方法提供线索.%In multiple sclerosis (MS),one strategy to reduce disability is enhancement of endogenous repair by remyelinating oligodendrocytes derived from oligodendrocyte progenitor cells (OP).An important prerequisite is determining the abundance of OP relative to oligodendrocytes in normal human central nervous system (CNS),which,in turn,requires reliable OP identification.To achieve this,cat and human optic nerves (ON) were subjected to varied preparation protocols,and the resultant neuroglial staining profiles correlated to generate an antigenic phenotype for OP applicable to human autopsy specimens.OP,interchangeably called NG2cells due to universal NG2 expression,were shown to comprise a separate class of neuroglial cells,related to oligodendrocytes by expression of the oligodendrocyte lineage transcription factors,Olig1 and Olig2.Despite their

  9. Role of angiotensin AT2 receptors and nitric oxide in the cardiopulmonary baroreflex control of renal sympathetic nerve activity in anaesthetised rats

    OpenAIRE

    Abdulla, Mohammed H.; Johns, Edward J.

    2013-01-01

    This study investigated the role of AT2 receptor activation and the possible interaction with nitric oxide (NO) in low-pressure baroreceptor regulation of renal sympathetic nerve activity (RSNA). Renal sympatho-inhibition to a saline volume expansion (VEP, 0.25% bwt/min I.V. for 30 min) was studied following intracerebroventricular (i.c.v.) saline, CGP42112 (CGP, AT2 agonist), PD123319 (PD, AT2 antagonist) and losartan (AT1 antagonist), and then in combination with L-NAME (NO synthase inhibit...

  10. Mechanisms of cell propulsion by active stresses

    Energy Technology Data Exchange (ETDEWEB)

    Carlsson, A E, E-mail: aec@wustl.edu [Department of Physics, Washington University, Campus Box 1105, One Brookings Drive, St. Louis, MO 63130 (United States)

    2011-07-15

    The mechanisms by which cytoskeletal flows and cell-substrate interactions interact to generate cell motion are explored by using a simplified model of the cytoskeleton as a viscous gel containing active stresses. This model yields explicit general results relating cell speed and traction forces to the distributions of active stress and cell-substrate friction. It is found that (i) the cell velocity is given by a function that quantifies the asymmetry of the active-stress distribution, (ii) gradients in cell-substrate friction can induce motion even when the active stresses are symmetrically distributed, (iii) the traction-force dipole is enhanced by protrusive stresses near the cell edges or contractile stresses near the center of the cell and (iv) the cell velocity depends biphasically on the cell-substrate adhesion strength if active stress is enhanced by adhesion. Specific experimental tests of the calculated dependences are proposed.

  11. A cell type-specific allele of the POU gene Oct-6 reveals Schwann cell autonomous function in nerve development and regeneration

    NARCIS (Netherlands)

    M. Ghazvini (Mehrnaz); W.J. Mandemakers (Wim); M.M. Jaegle (Martine); M. Piirsoo (Marko); M. Koutsourakis (Manousos); X. Smit (Xander); D.N. Meijer (Dies); M.J.F. Driegen (Siska); F.G. Grosveld (Frank)

    2002-01-01

    textabstractWhile an important role for the POU domain transcription factor Oct-6 in the developing peripheral nerve has been well established, studies into its exact role in nerve development and regeneration have been hampered by the high mortality rate of newborn Oct-6 mutant an

  12. A cell type-specific allele of the POU gene Oct-6 reveals Schwann cell autonomous function in nerve development and regeneration.

    NARCIS (Netherlands)

    M. Ghazvini (Mehrnaz); W.J. Mandemakers (Wim); M.M. Jaegle (Martine); M. Piirsoo (Marko); M. Koutsourakis (Manousos); X. Smit (Xander); F.G. Grosveld (Frank); D.N. Meijer (Dies); M.J.F. Driegen (Siska)

    2002-01-01

    textabstractWhile an important role for the POU domain transcription factor Oct-6 in the developing peripheral nerve has been well established, studies into its exact role in nerve development and regeneration have been hampered by the high mortality rate of newborn Oct-6 mutant animals. In this stu

  13. A silk sericin/silicone nerve guidance conduit promotes regeneration of a transected sciatic nerve.

    Science.gov (United States)

    Xie, Hongjian; Yang, Wen; Chen, Jianghai; Zhang, Jinxiang; Lu, Xiaochen; Zhao, Xiaobo; Huang, Kun; Li, Huili; Chang, Panpan; Wang, Zheng; Wang, Lin

    2015-10-28

    Peripheral nerve gap defects lead to significant loss of sensory or motor function. Tissue engineering has become an important alternative to nerve repair. Sericin, a major component of silk, is a natural protein whose value in tissue engineering has just begun to be explored. Here, the first time use of sericin in vivo is reported as a long-term implant for peripheral nerve regeneration. A sericin nerve guidance conduit is designed and fabricated. This conduit is highly porous with mechanical strength matching peripheral nerve tissue. It supports Schwann cell proliferation and is capable of up-regulating the transcription of glial cell derived neurotrophic factor and nerve growth factor in Schwann cells. The sericin conduit wrapped with a silicone conduit (sericin/silicone double conduits) is used for bridging repair of a 5 mm gap in a rat sciatic nerve transection model. The sericin/silicone double conduits achieve functional recovery comparable to that of autologous nerve grafting as evidenced by drastically improved nerve function and morphology. Importantly, this improvement is mainly attributed to the sericin conduit as the silicone conduit alone only produces marginal functional recovery. This sericin/silicone-double-conduit strategy offers an efficient and valuable alternative to autologous nerve grafting for repairing damaged peripheral nerve. PMID:26332703

  14. The cell biology of T-dependent B cell activation

    DEFF Research Database (Denmark)

    Owens, T; Zeine, R

    1989-01-01

    The requirement that CD4+ helper T cells recognize antigen in association with class II Major Histocompatibility Complex (MHC) encoded molecules constrains T cells to activation through intercellular interaction. The cell biology of the interactions between CD4+ T cells and antigen-presenting cells...

  15. Inflammatory cytokines in degeneration, regeneration and maintenance of sciatic nerve

    OpenAIRE

    Yokoyama, Shigeru

    2011-01-01

    Inflammatory cytokines play important roles in a variety of pathophysiological changes associated with traumatic injury and demyelinating disorders in the peripheral nervous system. After sciatic nerve injury, proinflammatory cytokines such as interleukin 1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNFα) are produced by and act on neurons, Schwann cells, and infiltrating inflammatory cells at the lesion site. Underlying these processes is receptor-mediated activation of intr...

  16. Immediate versus delayed primary nerve repair in the rabbit sciatic nerve.

    Science.gov (United States)

    Piskin, Ahmet; Altunkaynak, Berrin Zühal; Çitlak, Atilla; Sezgin, Hicabi; Yazιcι, Ozgür; Kaplan, Süleyman

    2013-12-25

    It is well known that peripheral nerve injury should be treated immediately in the clinic, but in some instances, repair can be delayed. This study investigated the effects of immediate versus delayed (3 days after injury) neurorrhaphy on repair of transected sciatic nerve in New Zealand rabbits using stereological, histomorphological and biomechanical methods. At 8 weeks after immediate and delayed neurorrhaphy, axon number and area in the sciatic nerve, myelin sheath and epineurium thickness, Schwann cell morphology, and the mechanical property of nerve fibers did not differ obviously. These results indicate that delayed neurorrhaphy do not produce any deleterious effect on sciatic nerve repair. PMID:25206663

  17. Effects of perindopril on cardiac sympathetic nerve activity in patients with congestive heart failure: comparison with enalapril

    Energy Technology Data Exchange (ETDEWEB)

    Kasama, Shu; Toyama, Takuji; Suzuki, Tadashi; Kurabayashi, Masahiko [Gunma University School of Medicine, Department of Cardiovascular Medicine, Maebashi, Gunma (Japan); Kumakura, Hisao; Takayama, Yoshiaki; Ichikawa, Shuichi [Cardiovascular Hospital of Central Japan, Department of Internal Medicine, Gunma (Japan)

    2005-08-01

    The production of aldosterone in the heart is suppressed by the angiotensin-converting enzyme (ACE) inhibitor perindopril in patients with congestive heart failure (CHF). Moreover, perindopril has been reported to have more cardioprotective effects than enalapril. Forty patients with CHF [left ventricular ejection fraction (LVEF) <45%; mean 33{+-}7%] were randomly assigned to perindopril (2 mg/day; n=20) or enalapril (5 mg/day; n=20). All patients were also treated with diuretics. The delayed heart/mediastinum count (H/M) ratio, delayed total defect score (TDS) and washout rate (WR) were determined from {sup 123}I-meta-iodobenzylguanidine (MIBG) images, and plasma brain natriuretic peptide (BNP) concentrations were measured before and 6 months after treatment. The left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV) and LVEF were also determined by echocardiography. After treatment, in patients receiving perindopril, TDS decreased from 39{+-}10 to 34{+-}9 (P<0.01), H/M ratios increased from 1.62{+-}0.27 to 1.76{+-}0.29 (P<0.01), WR decreased from 50{+-}14% to 42{+-}14% (P<0.05) and plasma BNP concentrations decreased from 226{+-}155 to 141{+-}90 pg/ml (P<0.0005). In addition, the LVEDV decreased from 180{+-}30 to 161{+-}30 ml (P<0.05) and the LVESV decreased from 122{+-}35 to 105{+-}36 ml (P<0.05). Although the LVEF tended to increase, the change was not statistically significant (from 33{+-}8% to 36{+-}12%; P=NS). On the other hand, there were no significant changes in these parameters in patients receiving enalapril. Plasma BNP concentrations, {sup 123}I-MIBG scintigraphic and echocardiographic parameters improved after 6 months of perindopril treatment. These findings indicate that perindopril treatment can ameliorate the cardiac sympathetic nerve activity and the left ventricular performance in patients with CHF. (orig.)

  18. Differentiation of immortal cells inhibits telomerase activity.

    OpenAIRE

    Sharma, H W; Sokoloski, J A; Perez, J.R.; Maltese, J Y; Sartorelli, A C; Stein, C A; Nichols, G; Khaled, Z.; Telang, N T; Narayanan, R.

    1995-01-01

    Telomerase, a ribonucleic acid-protein complex, adds hexameric repeats of 5'-TTAGGG-3' to the ends of mammalian chromosomal DNA (telomeres) to compensate for the progressive loss that occurs with successive rounds of DNA replication. Although somatic cells do not express telomerase, germ cells and immortalized cells, including neoplastic cells, express this activity. To determine whether the phenotypic differentiation of immortalized cells is linked to the regulation of telomerase activity, t...

  19. Application of alcian blue in the electron microscopic study of mouse and human cerebral cortex nerve cells.

    Science.gov (United States)

    Castejón, H V; Castejón, O J; Viloria, M E

    1976-01-01

    Alcian blue is a cationic dye which has been used in the histochemical field for the demonstration of polyanions especially carboxylated and sulphated. The results obtained in neurons when this dye was applied to human and mouse cerebral cortex and studied with the electron microscope are the object of the present report. The CNS of normal adult mice was fixed by vascular perfusion with 2% glutaraldehyde-0.1 M sodium cacodylate-0.1 M sucrose at pH = 6.8 followed by the same fixative with the addition of 0.5% alcian blue. After perfusion, brain cortex was taken out, sectioned into small blocks and immersed in a fresh similar mixture and subsequently in OSO4. Blocks were dehydrated and embedded in araldite. Ultrathin sections were doubly stained with uranyl and lead salts. Human brain cortex taken from patients with cerebral edema was fixed by immersion with 6.5% glutaraldehyde-0.1 M sodium phosphate, pH = 7.4 followed by embedding in warm agar and sectioning in slices of 30 mum thickness which were impregnated by immersion in a mixture of 1% alcian blue-acetate buffer-3% glutaraldehyde at pH = 3.5 for 9 to 15 h at 4 degrees C and subsequently immersed in 1% buffered OSO4-0.1 M sucrose, pH = 7.4 for 2 h at 4 degrees S. Sections were dehydrated and embedded in araldite. Ultrathin sections were doubly stained by uranyl and lead salts. We have denominated the complete procedure in both instances GABOUL technique. The submicroscopic study of both tissues, at nerve cells, revealed the presence of an electron dense homogeneous substance thoroughly dispersed at the hyaloplasmic matrix of perikarya, processes and even synaptic endings. This substance was more evident around free and attached ribosomes, GOLGI apparatus, complex vesicles, dense bodies, microtubules, subsurface cisternae and synaptic vesicles. Canaliculi of endoplasmic reticulum and even the perinuclear cistern also showed a moderate content. It is suggested that this electron dense substance, being

  20. Effect of ultraviolet blood irradiation and oxygenation on nerve function and function of the red blood cell membrane pump in patients with acute cerebral infarction

    Institute of Scientific and Technical Information of China (English)

    Jiaquan Wang; Chun Mao; Kaifu Ma; Shiqing Wang

    2006-01-01

    BACKGROUND: Ultraviolet blood irradiation and oxygenation (UBIO) has obtained better clinical effect in treating acute cerebral infarction, but the mechanism underlying this effect remains unclear.OBJECTIVE: To observe the effect of UBIO on the nerve function and activities of K+-Na+-ATPase and Ca2+-Mg2+-ATPase activities on the red blood cell (RBC) membrane of patients with acute cerebral infarction.DESIGN: A randomized and controlled study.SETTING: Department of Neurology, Xiangfan Central Hospital.PARTICIPANTS: From January 2000 to December 2001, excluding those above 70 years old, 58 cases of 700 patients with acute cerebral infarction admitted in the Department of Neurology, Xiangfan Central Hospital, were recruited and divided into two groups according to the random number table: UBIO treated group (n=28), including 17 males and 11 females, aged 40-68 years; and control group (n=30), including 20males and 10 females, aged 44-69 years. All the patients agreed to participate in the therapeutic program and detected items. The general informations were comparable without obvious differences between the two groups (P > 0.05).METHODS: ① The patients in both groups received routine treatments, besides, those in the UBIO treated group were given UBIO treatment by using the XL-200 type therapeutic apparatus produced in Shijiazhuang, whose ultraviolet wave was set at 253.7 nm with the energy density of 0.568 J/m2 per second, UBIO treatment started from the second day after admission, once every other day, with a single course consisting of 5-7 treatments. ② In the UBIO treated group, the venous blood was sampled before and after the first, third and the completion of the treatment course respectively, the venous blood was taken at each corresponding time point in the control group. After centrifugation of the blood at 10 000 rounds per minute,the RBC membrane was separated and then the activities of K+-Na+-ATPase and Ca2+-Mg2+-ATPase were detected by means of

  1. Hypothalamic Paraventricular and Arcuate Nuclei Contribute to Elevated Sympathetic Nerve Activity in Pregnant Rats: Roles of Neuropeptide Y and α-Melanocyte-Stimulating Hormone.

    Science.gov (United States)

    Shi, Zhigang; Cassaglia, Priscila A; Gotthardt, Laura C; Brooks, Virginia L

    2015-12-01

    Pregnancy increases sympathetic nerve activity (SNA), but the mechanisms are unknown. Here, we investigated the contributions of the hypothalamic paraventricular and arcuate nuclei in α-chloralose-anesthetized pregnant and nonpregnant rats. Baseline arterial pressure (AP) was lower, and heart rate (HR), lumbar sympathetic activity, and splanchnic SNA were higher in pregnant rats compared with nonpregnant rats. Inhibition of the paraventricular nucleus via bilateral muscimol nanoinjections decreased AP and HR more in pregnant rats than in nonpregnant rats and decreased lumbar SNA only in pregnant rats. Similarly, after arcuate muscimol nanoninjections, the decreases in AP, HR, and lumbar, renal, and splanchnic sympathetic nerve activities were greater in pregnant rats than in nonpregnant rats. Major arcuate neuronal groups that project to the paraventricular nucleus express inhibitory neuropeptide Y (NPY) and excitatory α-melanocyte-stimulating hormone. Inhibition of paraventricular melanocortin 3/4 receptors with SHU9119 also decreased AP, HR, and lumbar SNA in pregnant rats but not in nonpregnant rats. Conversely, paraventricular nucleus NPY expression was reduced in pregnant animals, and although blockade of paraventricular NPY Y1 receptors increased AP, HR, and lumbar sympathetic activity in nonpregnant rats, it had no effects in pregnant rats. Yet, the sympathoinhibitory, depressor, and bradycardic effects of paraventricular NPY nanoinjections were similar between groups. In conclusion, the paraventricular and arcuate nuclei contribute to increased basal SNA during pregnancy, likely due in part to decreased tonic NPY inhibition and increased tonic α-melanocyte-stimulating hormone excitation of presympathetic neurons in the paraventricular nucleus.

  2. Hypothalamic Paraventricular and Arcuate Nuclei Contribute to Elevated Sympathetic Nerve Activity in Pregnant Rats: Roles of Neuropeptide Y and α-Melanocyte-Stimulating Hormone.

    Science.gov (United States)

    Shi, Zhigang; Cassaglia, Priscila A; Gotthardt, Laura C; Brooks, Virginia L

    2015-12-01

    Pregnancy increases sympathetic nerve activity (SNA), but the mechanisms are unknown. Here, we investigated the contributions of the hypothalamic paraventricular and arcuate nuclei in α-chloralose-anesthetized pregnant and nonpregnant rats. Baseline arterial pressure (AP) was lower, and heart rate (HR), lumbar sympathetic activity, and splanchnic SNA were higher in pregnant rats compared with nonpregnant rats. Inhibition of the paraventricular nucleus via bilateral muscimol nanoinjections decreased AP and HR more in pregnant rats than in nonpregnant rats and decreased lumbar SNA only in pregnant rats. Similarly, after arcuate muscimol nanoninjections, the decreases in AP, HR, and lumbar, renal, and splanchnic sympathetic nerve activities were greater in pregnant rats than in nonpregnant rats. Major arcuate neuronal groups that project to the paraventricular nucleus express inhibitory neuropeptide Y (NPY) and excitatory α-melanocyte-stimulating hormone. Inhibition of paraventricular melanocortin 3/4 receptors with SHU9119 also decreased AP, HR, and lumbar SNA in pregnant rats but not in nonpregnant rats. Conversely, paraventricular nucleus NPY expression was reduced in pregnant animals, and although blockade of paraventricular NPY Y1 receptors increased AP, HR, and lumbar sympathetic activity in nonpregnant rats, it had no effects in pregnant rats. Yet, the sympathoinhibitory, depressor, and bradycardic effects of paraventricular NPY nanoinjections were similar between groups. In conclusion, the paraventricular and arcuate nuclei contribute to increased basal SNA during pregnancy, likely due in part to decreased tonic NPY inhibition and increased tonic α-melanocyte-stimulating hormone excitation of presympathetic neurons in the paraventricular nucleus. PMID:26483343

  3. Telomerase activity in plasma cell dyscrasias

    OpenAIRE

    Xu, D; Zheng, C.; Bergenbrant, S; Holm, G; Björkholm, M.; Yi, Q; Gruber, A

    2001-01-01

    Activation of telomerase is essential for in vitro cellular immortalization and tumorigenesis. In the present study, we investigated telomerase activation and its implications in plasma cell dyscrasias including monoclonal gammopathy of undetermined significance (MGUS), multiple myeloma (MM) and plasma cell leukaemia (PCL). All 5 patients with MGUS exhibited normal levels of telomerase activity in their plasma cells. Elevated telomerase activity was found in the samples from 21/27 patients wi...

  4. Leptin acts in the forebrain to differentially influence baroreflex control of lumbar, renal, and splanchnic sympathetic nerve activity and heart rate.

    Science.gov (United States)

    Li, Baoxin; Shi, Zhigang; Cassaglia, Priscila A; Brooks, Virginia L

    2013-04-01

    Although leptin is known to increase sympathetic nerve activity (SNA), we tested the hypothesis that leptin also enhances baroreflex control of SNA and heart rate (HR). Using α-chloralose anesthetized male rats, mean arterial pressure (MAP), HR, lumbar SNA (LSNA), splanchnic SNA (SSNA), and renal SNA (RSNA) were recorded before and for 2 hours after lateral cerebroventricular leptin or artificial cerebrospinal fluid administration. Baroreflex function was assessed using a 4-parameter sigmoidal fit of HR and SNA responses to slow ramp (3-5 minutes) changes in MAP, induced by intravenous infusion of nitroprusside and phenylephrine. Leptin (3 μg) increased (P<0.05) basal LSNA, SSNA, RSNA, HR, and MAP, and the LSNA, SSNA, RSNA, and HR baroreflex maxima. Leptin also increased gain of baroreflex control of LSNA and RSNA, but not of SSNA or HR. The elevations in HR were eliminated by pretreatment with methscopalamine, to block parasympathetic nerve activity; however, after cardiac sympathetic blockade with atenolol, leptin still increased basal HR and MAP and the HR baroreflex maximum and minimum. Leptin (1.5 μg) also increased LSNA and enhanced LSNA baroreflex gain and maximum, but did not alter MAP, HR, or the HR baroreflex. Lateral cerebroventricular artificial cerebrospinal fluid had no effects. Finally, to test whether leptin acts in the brain stem, leptin (3 μg) was infused into the 4th ventricle; however, no significant changes were observed. In conclusion, leptin acts in the forebrain to differentially influence baroreflex control of LSNA, RSNA, SSNA, and HR, with the latter action mediated via suppression of parasympathetic nerve activity. PMID:23424232

  5. Cell division activity during apical hook development

    NARCIS (Netherlands)

    Raz, V.; Koornneef, M.

    2001-01-01

    Growth during plant development is predominantly governed by the combined activities of cell division and cell elongation. The relative contribution of both activities controls the growth of a tissue. A fast change in growth is exhibited at the apical hypocotyl of etiolated seedlings where cells gro

  6. Autocrine fibronectin from differentiating mesenchymal stem cells induces the neurite elongation in vitro and promotes nerve fiber regeneration in transected spinal cord injury.

    Science.gov (United States)

    Zeng, Xiang; Ma, Yuan-Huan; Chen, Yuan-Feng; Qiu, Xue-Cheng; Wu, Jin-Lang; Ling, Eng-Ang; Zeng, Yuan-Shan

    2016-08-01

    Extracellular matrix (ECM) expression is temporally and spatially regulated during the development of stem cells. We reported previously that fibronectin (FN) secreted by bone marrow mesenchymal stem cells (MSCs) was deposited on the surface of gelatin sponge (GS) soon after culture. In this study, we aimed to assess the function of accumulated FN on neuronal differentiating MSCs as induced by Schwann cells (SCs) in three dimensional transwell co-culture system. The expression pattern and amount of FN of differentiating MSCs was examined by immunofluorescence, Western blot and immunoelectron microscopy. The results showed that FN accumulated inside GS scaffold, although its mRNA expression in MSCs was progressively decreased during neural induction. MSC-derived neuron-like cells showed spindle-shaped cell body and long extending processes on FN-decorated scaffold surface. However, after blocking of FN function by application of monoclonal antibodies, neuron-like cells showed flattened cell body with short and thick neurites, together with decreased expression of integrin β1. In vivo transplantation study revealed that autocrine FN significantly facilitated endogenous nerve fiber regeneration in spinal cord transection model. Taken together, the present results showed that FN secreted by MSCs in the early stage accumulated on the GS scaffold and promoted the neurite elongation of neuronal differentiating MSCs as well as nerve fiber regeneration after spinal cord injury. This suggests that autocrine FN has a dynamic influence on MSCs in a three dimensional culture system and its potential application for treatment of traumatic spinal cord injury. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1902-1911, 2016. PMID:26991461

  7. Uptake and metabolism of fructose by rat neocortical cells in vivo and by isolated nerve terminals in vitro

    OpenAIRE

    Hassel, Bjørnar; Elsais, Ahmed; Frøland, Anne Sofie; Taubøll, Erik; Gjerstad, Leif; Quan, Yi; Dingledine, Ray; Rise, Frode

    2015-01-01

    Fructose reacts spontaneously with proteins in the brain to form advanced glycation end products (AGE) that may elicit neuroinflammation and cause brain pathology, including Alzheimer’s disease. We investigated whether fructose is eliminated by oxidative metabolism in neocortex. Injection of [14C]fructose or its AGE-prone metabolite [14C]glyceraldehyde into rat neocortex in vivo led to formation of 14C-labeled alanine, glutamate, aspartate, GABA, and glutamine. In isolated neocortical nerve t...

  8. Imatinib mesylate inhibits cell growth of malignant peripheral nerve sheath tumors in vitro and in vivo through suppression of PDGFR-β

    International Nuclear Information System (INIS)

    Malignant peripheral nerve sheath tumors (MPNSTs) are highly aggressive and associated with poor prognosis. Basic research to develop new treatment regimens is critically needed. The effects of imatinib mesylate on MPNSTs were examined in six human MPNST cell lines and in a xenograft mouse model. The results showed expression of platelet-derived growth factor receptor-β and suppression of its phosphorylation by imatinib mesylate in all six cell lines. Imatinib mesylate effectively suppressed MPNST cell growth in vitro at concentrations similar to those used clinically (1.46 − 4.6 μM) in three of six cell lines. Knockdown of PDGFR-β by transfection with a specific siRNA also caused significant reduction in cell proliferation in the sensitive cell lines, but not in the resistant cell lines. Furthermore, imatinib mesylate also significantly suppressed colony formation within soft agar and tumor growth in xenograft models using two of the three sensitive MPNST cell lines. There was excellent agreement between in vitro and in vivo sensitivity to imatinib mesylate, suggesting possible selection of imatinib-sensitive tumors by in vitro analysis. The results suggest that imatinib mesylate may be useful in the treatment of MPNST patients and in vitro studies may help select cells that are sensitive to imatinib mesylate in vivo

  9. An effect of wrapping peripheral nerve anastomosis with pedicled muscle flap on nerve regeneration in experiment

    Directory of Open Access Journals (Sweden)

    Naumenko L.Yu.

    2010-01-01

    Full Text Available Despite intrinsic capacity of peripheral nerves to regenerate, functional outcomes of peripheral nerves injury remain poor. Nerve ischemia, intra-/perineurial fibrosis and neuroma formation contribute a lot to that. Several authors demonstrated beneficial effects of increased vascularization at the site of injury on peripheral nerves regeneration. The use of highly vascularized autologous tissues (greater omentum as a source of peripheral nerves neovascularization shows promising re-sults. We proposed a surgical technique in which injured peripheral nerves anastomosis was wrapped in a pedicled muscular flap and performed morphological assessment of the efficacy of such technique with the aid of immunohistochemistry. 14 rats (which underwent sciatic nerve transection were operated according to proposed technique. Another 14 rats, in which only end-to-end nerve anastomosis (without muscular wrapping was performed served as controls. Morphological changes were evaluated at 3 weeks and 3 months periods. Higher blood vessel and axon counts were observed in experimental groups at both checkpoints. There was also an increase in Schwann cells and macrophages counts, and less collagen content in pe-ripheral nerves of experimental groups. Axons in neuromas of experimental groups showed a higher degree of arrangement. We conclude that proposed surgical technique provides better vascularisation of injured peripheral nerves, which is beneficial for nerve regeneration.

  10. Neuronal injury external to the retina rapidly activates retinal glia, followed by elevation of markers for cell cycle re-entry and death in retinal ganglion cells.

    Directory of Open Access Journals (Sweden)

    Alba Galan

    Full Text Available Retinal ganglion cells (RGCs are neurons that relay visual signals from the retina to the brain. The RGC cell bodies reside in the retina and their fibers form the optic nerve. Full transection (axotomy of the optic nerve is an extra-retinal injury model of RGC degeneration. Optic nerve transection permits time-kinetic studies of neurodegenerative mechanisms in neurons and resident glia of the retina, the early events of which are reported here. One day after injury, and before atrophy of RGC cell bodies was apparent, glia had increased levels of phospho-Akt, phospho-S6, and phospho-ERK1/2; however, these signals were not detected in injured RGCs. Three days after injury there were increased levels of phospho-Rb and cyclin A proteins detected in RGCs, whereas these signals were not detected in glia. DNA hyperploidy was also detected in RGCs, indicative of cell cycle re-entry by these post-mitotic neurons. These events culminated in RGC death, which is delayed by pharmacological inhibition of the MAPK/ERK pathway. Our data show that a remote injury to RGC axons rapidly conveys a signal that activates retinal glia, followed by RGC cell cycle re-entry, DNA hyperploidy, and neuronal death that is delayed by preventing glial MAPK/ERK activation. These results demonstrate that complex and variable neuro-glia interactions regulate healthy and injured states in the adult mammalian retina.

  11. Active cell mechanics: Measurement and theory.

    Science.gov (United States)

    Ahmed, Wylie W; Fodor, Étienne; Betz, Timo

    2015-11-01

    Living cells are active mechanical systems that are able to generate forces. Their structure and shape are primarily determined by biopolymer filaments and molecular motors that form the cytoskeleton. Active force generation requires constant consumption of energy to maintain the nonequilibrium activity to drive organization and transport processes necessary for their function. To understand this activity it is necessary to develop new approaches to probe the underlying physical processes. Active cell mechanics incorporates active molecular-scale force generation into the traditional framework of mechanics of materials. This review highlights recent experimental and theoretical developments towards understanding active cell mechanics. We focus primarily on intracellular mechanical measurements and theoretical advances utilizing the Langevin framework. These developing approaches allow a quantitative understanding of nonequilibrium mechanical activity in living cells. This article is part of a Special Issue entitled: Mechanobiology.

  12. Hippocampal plasticity after a vagus nerve injury in the rat

    Institute of Scientific and Technical Information of China (English)

    Giulia Ronchi; Vitaly Ryu; ong ling; Krzysztof Czaja

    2012-01-01

    Stimulation of the vagus nerve has been previously reported to promote neural plasticity and neurogenesis in the brain. Several studies also revealed plastic changes in the spinal cord after injuries to somatosensory nerves originating from both the brachial and lumbo-sacral plexuses. However, the neurogenic responses of the brain to the injury of the viscerosensory innervation are not as yet well understood. In the present study, we investigated whether cells in the dentate gyrus of the hippocampus respond to a chemical and physical damage to the vagus nerve in the adult rat. Intraperitoneal capsaicin administration was used to damage non-myelinated vagal afferents while subdiaphragmatic vagotomy was used to damage both the myelinated and non-myelinated vagal afferents. The 5-bromo-2-deoxyuridine (BrdU) incorporation together with cell-specific markers was used to study neural proliferation in subgranular zone, granule cell layer, molecular layer and hilus of the dentate gyrus. Microglia activation was determined by quantifying changes in the intensity of fluorescent staining with a primary antibody against ionizing calcium adapter-binding molecule 1. Results revealed that vagotomy decreased BrdU incorporation in the hilus 15 days after injury compared to the capsaicin group. Capsaicin administration decreased BrdU incorporation in the granular cell layer 60 days after the treatment. Capsaicin decreased the number of doublecortin-expressing cells in the dentate gyrus, whereas vagotomy did not alter the expression of doublecortin in the hippocampus. Both the capsaicin- and the vagotomy-induced damage to the vagus nerve decreased microglia activation in the hippocampus at 15 days after the injury. At 30 days post injury, capsaicin-treated and vagotomized rats revealed significantly more activated microglia. Our findings show that damage to the subdiaphragmatic vagus in adult rats is followed by microglia activation and long-lasting changes in the dentate gyrus

  13. Genetically-increased taste cell population with Gα-gustducin-coupled sweet receptors is associated with increase of gurmarin-sensitive taste nerve fibers in mice

    Directory of Open Access Journals (Sweden)

    Katsukawa Hideo

    2009-12-01

    Full Text Available Abstract Background The peptide gurmarin is a selective sweet response inhibitor for rodents. In mice, gurmarin sensitivity differs among strains with gurmarin-sensitive C57BL and gurmarin-poorly-sensitive BALB strains. In C57BL mice, sweet-responsive fibers of the chorda tympani (CT nerve can be divided into two distinct populations, gurmarin-sensitive (GS and gurmarin-insensitive (GI types, suggesting the existence of two distinct reception pathways for sweet taste responses. By using the dpa congenic strain (dpa CG whose genetic background is identical to BALB except that the gene(s controlling gurmarin sensitivity are derived from C57BL, we previously found that genetically-elevated gurmarin sensitivity in dpa CG mice, confirmed by using behavioral response and whole CT nerve response analyses, was linked to a greater taste cell population co-expressing sweet taste receptors and a Gα protein, Gα-gustducin. However, the formation of neural pathways from the increased taste cell population to nerve fibers has not yet been examined. Results Here, we investigated whether the increased taste cell population with Gα-gustducin-coupled sweet receptors would be associated with selective increment of GS fiber population or nonselective shift of gurmarin sensitivities of overall sweet-responsive fibers by examining the classification of GS and GI fiber types in dpa CG and BALB mice. The results indicated that dpa CG, like C57BL, possess two distinct populations of GS and GI types of sweet-responsive fibers with almost identical sizes (dpa CG: 13 GS and 16 GI fibers; C57BL: 16 GS and 14 GI fibers. In contrast, BALB has only 3 GS fibers but 18 GI fibers. These data indicate a marked increase of the GS population in dpa CG. Conclusion These results suggest that the increased cell population expressing T1r2/T1r3/Gα-gustducin in dpa CG mice may be associated with an increase of their matched GS type fibers, and may form the distinct GS sweet reception

  14. Cell death sensitization of leukemia cells by opioid receptor activation

    Science.gov (United States)

    Friesen, Claudia; Roscher, Mareike; Hormann, Inis; Fichtner, Iduna; Alt, Andreas; Hilger, Ralf A.; Debatin, Klaus-Michael; Miltner, Erich

    2013-01-01

    Cyclic AMP (cAMP) regulates a number of cellular processes and modulates cell death induction. cAMP levels are altered upon stimulation of specific G-protein-coupled receptors inhibiting or activating adenylyl cyclases. Opioid receptor stimulation can activate inhibitory Gi-proteins which in turn block adenylyl cyclase activity reducing cAMP. Opioids such as D,L-methadone induce cell death in leukemia cells. However, the mechanism how opioids trigger apoptosis and activate caspases in leukemia cells is not understood. In this study, we demonstrate that downregulation of cAMP induced by opioid receptor activation using the opioid D,L-methadone kills and sensitizes leukemia cells for doxorubicin treatment. Enhancing cAMP levels by blocking opioid-receptor signaling strongly reduced D,L-methadone-induced apoptosis, caspase activation and doxorubicin-sensitivity. Induction of cell death in leukemia cells by activation of opioid receptors using the opioid D,L-methadone depends on critical levels of opioid receptor expression on the cell surface. Doxorubicin increased opioid receptor expression in leukemia cells. In addition, the opioid D,L-methadone increased doxorubicin uptake and decreased doxorubicin efflux in leukemia cells, suggesting that the opioid D,L-methadone as well as doxorubicin mutually increase their cytotoxic potential. Furthermore, we found that opioid receptor activation using D,L-methadone alone or in addition to doxorubicin inhibits tumor growth significantly in vivo. These results demonstrate that opioid receptor activation via triggering the downregulation of cAMP induces apoptosis, activates caspases and sensitizes leukemia cells for doxorubicin treatment. Hence, opioid receptor activation seems to be a promising strategy to improve anticancer therapies. PMID:23633472

  15. Erythropoietin enhances nerve repair in anti-ganglioside antibody-mediated models of immune neuropathy.

    Directory of Open Access Journals (Sweden)

    Gang Zhang

    Full Text Available Guillain-Barré syndrome (GBS is a monophasic immune neuropathic disorder in which a significant proportion of patients have incomplete recovery. The patients with incomplete recovery almost always have some degree of failure of axon regeneration and target reinnervation. Anti-ganglioside antibodies (Abs are the most commonly recognized autoimmune markers in all forms of GBS and specific Abs are associated with the slow/poor recovery. We recently demonstrated that specific anti-ganglioside Abs inhibit axonal regeneration and nerve repair in preclinical models by activation of small GTPase RhoA and its downstream effectors. The objective of this study was to determine whether erythropoietin (EPO, a pleiotropic cytokine with neuroprotective and neurotrophic properties, enhances nerve regeneration in preclinical cell culture and animal models of autoimmune neuropathy/nerve repair generated with monoclonal and patient derived Abs. Primary neuronal cultures and a standardized sciatic crush nerve model were used to assess the efficacy of EPO in reversing inhibitory effects of anti-ganglioside Abs on nerve repair. We found that EPO completely reversed the inhibitory effects of anti-ganglioside Abs on axon regeneration in cell culture models and significantly improved nerve regeneration/repair in an animal model. Moreover, EPO-induced proregenerative effects in nerve cells are through EPO receptors and Janus kinase 2/Signal transducer and activator of transcription 5 pathway and not via early direct modulation of small GTPase RhoA. These preclinical studies indicate that EPO is a viable candidate drug to develop further for neuroprotection and enhancing nerve repair in patients with GBS.

  16. Ganglion cell complex and retinal nerve fiber layer measured by fourier-domain optical coherence tomography for early detection of structural damage in patients with preperimetric glaucoma

    Directory of Open Access Journals (Sweden)

    Rolle T

    2011-07-01

    Full Text Available Teresa Rolle, Cristina Briamonte, Daniela Curto, Federico Maria GrignoloEye Clinic, Section of Ophthalmology, Department of Clinical Physiopathology, University of Torino, Torino, ItalyAims: To evaluate the capability of Fourier-domain optical coherence tomography (FD-OCT to detect structural damage in patients with preperimetric glaucoma.Methods: A total of 178 Caucasian subjects were enrolled in this cohort study: 116 preperimetric glaucoma patients and 52 healthy subjects. Using three-dimensional FD-OCT, the participants underwent imaging of the ganglion cell complex (GCC and the optic nerve head. Sensitivity, specificity, likelihood ratios, and predictive values were calculated for all parameters at the first and fifth percentiles. Areas under the curves (AUCs were generated for all parameters and were compared (Delong test. For both the GCC and the optic nerve head protocols, the OR logical disjunction (Boolean logic operator was calculated.Results: The AUCs didn’t significantly differ. Macular global loss volume had the largest AUC (0.81. Specificities were high at both the fifth and first percentiles (up to 97%, but sensitivities were low, especially at the first percentile (55%–27%.Conclusion: Macular and papillary diagnostic accuracies did not differ significantly based on the 95% confidence interval. The computation of the Boolean OR operator has been found to boost diagnostic accuracy. Using the software-provided classification, sensitivity and diagnostic accuracy were low for both the retinal nerve fiber layer and the GCC scans. FD-OCT does not seem to be decisive for early detection of structural damage in patients with no functional impairment. This suggests that there is a need for analysis software to be further refined to enhance glaucoma diagnostic capability.Keywords: OCT, RNFL, GCC, diagnostic accuracy 

  17. 同种异体神经复合体修复兔坐骨神经缺损的研究%Planting fetus rabbit schwann cells into the extracted acellular nerve graft of homogeneity in repairing rabbit sciatic nerve defect

    Institute of Scientific and Technical Information of China (English)

    杨小华; 韩金豹; 张沉冰; 田德虎; 韩久卉

    2009-01-01

    Objective To plant fetus rabbit Schwann cells that were cultured and purified in vitro into the chemically extracted acellular nerve graft of homogeneity and made it into bridging complex. Then transplant the bridging complex into the rabbit defective sciatic nerve. The experiment was designed to investigate the effect of the nerve allografts on the functional recovery and the condition of nerve regeneration. Methods 48 adult healthy New-Zealand albino rabbits,weighing 1.5-2.0 kg,were randomly divided into 2 groups with 24 rabbits each group,based on different grafts. The bridging complex were composed of Schwann cell, then transplanted it to repair defective sciatic nerve of the experiment group rabbit. The control group did not transplant Schwann cells. The sciatic nerve of lower left limb was cut in order to emerge 2cm nerves defect for each rabbit,then was transplated with different grafts. Observed the ulcers on the feet of the rabbit 4,8 and 16 weeks after operation. To observe sciatic nerve regeneration and myelination by light microscope. To observe the information of nerve regeneration and myelination and the ultrastructural change of the mitochondrion, the microtubule, the microfilament and Schwann cells by electron microscope. Make use of the analytical system on picture to treat the number of regenerated nerve fiber and the axon diameter and the thickness of myelin sheath of medullated nerve fibers,then measured the wet weight of the triceps surae. Then analyzed them in statistics. Results After operation, the immunological rejection was not found in the operating field. The experimental group was better than the control group in healing of ulcers, after 4,8,16 weeks,the number of regenerated nerve fiber and the axon diameter and the thickness of myelin sheath of medullated nervefibers (906.25 ± 30.68,1726.25 ±51. 89,2825.13 ± 22.79) , (5.35 ± 0.62,5.46 ±0.38,5.59 ±0.80), (1.65 ±0.37,1.75 ±0.41,1.83 ±0.49) (P 0.05). But after 8 and 16 weeks

  18. Lactobacilli Differentially Activate Natural Killer Cells

    DEFF Research Database (Denmark)

    Fink, Lisbeth Nielsen; Christensen, Hanne Risager; Frøkiær, Hanne

    bacteria on regulatory functions of NK-cells. Here, we have investigated how human gut flora-derived non-pathogenic lactobacilli affect NK cells in vitro, by measuring proliferation and IFN-gamma production of human peripheral blood NK cells upon bacterial stimulation. CD3-CD56+ NK cells were isolated from...... having engulfed bacteria, stimulated the growth of the NK cells. In contrast, a Lactobacillus paracasei strain caused the NK cells to proliferate only in the presence of monocytes. These results demonstrate that various lactobacilli have the capacity to activate NK cells in vitro, in a monocyte dependent...

  19. Assessment of central chemosensitivity and cardiac sympathetic nerve activity using I-123 MIBG imaging in central sleep apnea syndrome in patients with dilated cardiomyopathy

    International Nuclear Information System (INIS)

    Iodine-123 m-iodobenzylguanidine (MIBG) imaging has been used to study cardiac sympathetic function in various cardiac diseases. Central sleep apnea syndrome (CSAS) occurs frequently in patients with chronic heart failure (CHF) and is reported to be associated with a poor prognosis. One of the mechanisms of its poor prognosis may be related to impaired cardiac sympathetic activity. However, the relationship between chemosensitivity to carbon dioxide, which is reported to correlate with the severity of CSAS, and cardiac sympathetic activity has not been investigated. Therefore, this study was undertaken to assess cardiac sympathetic function and chemosensitivity to carbon dioxide in CHF patients. The oxygen desaturation index (ODI) was evaluated in 21 patients with dilated cardiomyopathy (male/female: 19/2, left ventricular ejection fraction (LVEF)5 times/h underwent polysomnography. Patients with an apnea hypopnea index >15/h but without evidence of obstructive apnea were defined as having CSAS. Early (15 min) and delayed (4 hr) planar MIBG images were obtained from these patients. The mean counts in the whole heart and the mediastinum were obtained. The heart-to-mediastinum count ratio of the delayed image (H/M) and the corrected myocardial washout rate (WR) were also calculated. The central chemoreflex was assessed with the rebreathing method using a hypercapnic gas mixture (7% CO2 and 93% O2). Ten of the 21 patients had CSAS. The H/M ratio was similar in patients both with and without CSAS (1.57±0.18 vs. 1.59±0.14, p=0.82). However, the WR was higher in patients with CSAS than in patients without CSAS (40±8% vs. 30±12%, p<0.05). ODI significantly correlated with central chemosensitivity to carbon dioxide. Moreover, there was a highly significant correlation between WR and central chemosensitivity (r=0.65, p<0.05). However, there was no correlation between ODI and the WR (r=0.36, p=0.11). Cardiac sympathetic nerve activity in patients with CHF and CSAS is

  20. Sciatic nerve regeneration in rats by a promising electrospun collagen/poly(ε-caprolactone nerve conduit with tailored degradation rate

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    Jiang Xinquan

    2011-07-01

    Full Text Available Abstract Background To cope with the limitations faced by autograft acquisitions particularly for multiple nerve injuries, artificial nerve conduit has been introduced by researchers as a substitute for autologous nerve graft for the easy specification and availability for mass production. In order to best mimic the structures and components of autologous nerve, great efforts have been made to improve the designation of nerve conduits either from materials or fabrication techniques. Electrospinning is an easy and versatile technique that has recently been used to fabricate fibrous tissue-engineered scaffolds which have great similarity to the extracellular matrix on fiber structure. Results In this study we fabricated a collagen/poly(ε-caprolactone (collagen/PCL fibrous scaffold by electrospinning and explored its application as nerve guide substrate or conduit in vitro and in vivo. Material characterizations showed this electrospun composite material which was made of submicron fibers possessed good hydrophilicity and flexibility. In vitro study indicated electrospun collagen/PCL fibrous meshes promoted Schwann cell adhesion, elongation and proliferation. In vivo test showed electrospun collagen/PCL porous nerve conduits successfully supported nerve regeneration through an 8 mm sciatic nerve gap in adult rats, achieving similar electrophysiological and muscle reinnervation results as autografts. Although regenerated nerve fibers were still in a pre-mature stage 4 months postoperatively, the implanted collagen/PCL nerve conduits facilitated more axons regenerating through the conduit lumen and gradually degraded which well matched the nerve regeneration rate. Conclusions All the results demonstrated this collagen/PCL nerve conduit with tailored degradation rate fabricated by electrospinning could be an efficient alternative to autograft for peripheral nerve regeneration research. Due to its advantage of high surface area for cell attachment, it

  1. Expression of apolipoprotein E during nerve degeneration and regeneration

    OpenAIRE

    Ignatius, M J; Gebicke-Härter, P J; Skene, J H; Schilling, J W; Weisgraber, K H; Mahley, R. W.; Shooter, E M

    1986-01-01

    A 37-kDa glycoprotein has been described recently, whose synthesis is dramatically increased after injury of the rat sciatic and optic nerves. Cells in the nerve sheath, distal to the site of injury, produce and secrete large amounts of this protein, so that by 3 weeks after injury, it represents 2-5% of the total soluble extracellular protein in the regenerating sciatic nerve sheath, although it fails to accumulate in damaged optic nerve. Results presented here reveal extensive homology betw...

  2. Nerve conduction velocity

    Science.gov (United States)

    ... to measure the speed of the nerve signals. Electromyography (recording from needles placed into the muscles) is ... Often, the nerve conduction test is followed by electromyography (EMG). In this test, needles are placed into ...

  3. A preconditioning nerve lesion inhibits mechanical pain hypersensitivity following subsequent neuropathic injury

    Directory of Open Access Journals (Sweden)

    Wu Ann

    2011-01-01

    Full Text Available Abstract Background A preconditioning stimulus can trigger a neuroprotective phenotype in the nervous system - a preconditioning nerve lesion causes a significant increase in axonal regeneration, and cerebral preconditioning protects against subsequent ischemia. We hypothesized that a preconditioning nerve lesion induces gene/protein modifications, neuronal changes, and immune activation that may affect pain sensation following subsequent nerve injury. We examined whether a preconditioning lesion affects neuropathic pain and neuroinflammation after peripheral nerve injury. Results We found that a preconditioning crush injury to a terminal branch of the sciatic nerve seven days before partial ligation of the sciatic nerve (PSNL; a model of neuropathic pain induced a significant attenuation of pain hypersensitivity, particularly mechanical allodynia. A preconditioning lesion of the tibial nerve induced a long-term significant increase in paw-withdrawal threshold to mechanical stimuli and paw-withdrawal latency to thermal stimuli, after PSNL. A preconditioning lesion of the common peroneal induced a smaller but significant short-term increase in paw-withdrawal threshold to mechanical stimuli, after PSNL. There was no difference between preconditioned and unconditioned animals in neuronal damage and macrophage and T-cell infiltration into the dorsal root ganglia (DRGs or in astrocyte and microglia activation in the spinal dorsal and ventral horns. Conclusions These results suggest that prior exposure to a mild nerve lesion protects against adverse effects of subsequent neuropathic injury, and that this conditioning-induced inhibition of pain hypersensitivity is not dependent on neuroinflammation in DRGs and spinal cord. Identifying the underlying mechanisms may have important implications for the understanding of neuropathic pain due to nerve injury.

  4. Effect of low-frequency transcutaneous electrical nerve stimulation on the action potential of spinal cord posterior horn cells in rats after peripheral nerve injury%低频电疗对白鼠周围神经损伤后脊髓后角神经细胞活动电位的影响

    Institute of Scientific and Technical Information of China (English)

    崔松彪; 赵和荣; 吴光; 朴虎男; 许梅花

    2006-01-01

    度刺激所引发的脊髓后角神经细胞的膜电位明显高于注射前[每10 s(174.5±0.41),(235.4±1.41)次,P<0.01].结论:低频电刺激能有效抑制被无害刺激所引发的脊髓后角神经细胞的活动电位,且静脉注射纳洛酮(8 mg/kg)可使之逆转到治疗前的水平,说明低频电疗可能是刺激中枢神经系统使其分泌内源鸦片物质,作用于脊髓后角细胞使其活性降低,从而达到缓解疼痛的目的.%BACKGROUND: Up to now, few studies related to the mechanism of low-frequency transcutaneous electrical nerve stimulation (TENS) in relieving pain, and the effect of low-frequency TENS on the activity potential of dorsal horn cells in rats after peripheral nerve injury. OBJECTIVE: To observe the effects of low-frequency TENS on the activity potential of dorsal horn cells induced by mechanical allodynia and thermal allodynia by using animal models of peripheral nerve injury, and observe the efficacy after interfering of naloxone. DESIGN: A randomized control animal study. SETTING: Department of Neurology, Affiliated Hospital of Medical College, Yanbian University. MATERIALS: The experiment was carried out in the central laboratory of Medical College, Yanbian University between February and October 2004. Eighty male Sprague-Dawley rats were used, and 60 random selected ones were operated to separate sciatic nerve, two branch tibial nerves and sural nerves of sciatic nerve were amputated after ligation, and peroneal nerve was left as the experimental group; the other 20 rats were placed at the origin after sciatic nerve was separated, and then the skin was sutured as the control group. METHODS: ① Pain detection (Behavioral test): At 1 week postoperatively, the rats were given mechanical allodynia and thermal allodynia once every 5 seconds for 10 times, and then the frequency of foot withdrawal was detected (0%-40% for mild pain, 40%-70% for moderate pain; 70% and above for severe pain). ② The spontaneous

  5. Measurement of myeloid cell immune suppressive activity.

    Science.gov (United States)

    Dolcetti, Luigi; Peranzoni, Elisa; Bronte, Vincenzo

    2010-11-01

    This unit presents simple methods to assess the immunosuppressive properties of immunoregulatory cells of myeloid origin, such as myeloid-derived suppressor cells (MDSCs), both in vitro and in vivo. These methods are general and could be adapted to test the impact of different suppressive populations on T cell activation, proliferation, and cytotoxic activity; moreover they could be useful to assess the influence exerted on immune suppressive pathways by genetic modifications, chemical inhibitors, and drugs.

  6. Three-Dimensional Gastrointestinal Organoid Culture in Combination with Nerves or Fibroblasts: A Method to Characterize the Gastrointestinal Stem Cell Niche.

    Science.gov (United States)

    Pastuła, Agnieszka; Middelhoff, Moritz; Brandtner, Anna; Tobiasch, Moritz; Höhl, Bettina; Nuber, Andreas H; Demir, Ihsan Ekin; Neupert, Steffi; Kollmann, Patrick; Mazzuoli-Weber, Gemma; Quante, Michael

    2016-01-01

    The gastrointestinal epithelium is characterized by a high turnover of cells and intestinal stem cells predominantly reside at the bottom of crypts and their progeny serve to maintain normal intestinal homeostasis. Accumulating evidence demonstrates the pivotal role of a niche surrounding intestinal stem cells in crypts, which consists of cellular and soluble components and creates an environment constantly influencing the fate of stem cells. Here we describe different 3D culture systems to culture gastrointestinal epithelium that should enable us to study the stem cell niche in vitro in the future: organoid culture and multilayered systems such as organotypic cell culture and culture of intestinal tissue fragments ex vivo. These methods mimic the in vivo situation in vitro by creating 3D culture conditions that reflect the physiological situation of intestinal crypts. Modifications of the composition of the culture media as well as coculturing epithelial organoids with previously described cellular components such as myofibroblasts, collagen, and neurons show the impact of the methods applied to investigate niche interactions in vitro. We further present a novel method to isolate labeled nerves from the enteric nervous system using Dclk1-CreGFP mice. PMID:26697073

  7. Three-Dimensional Gastrointestinal Organoid Culture in Combination with Nerves or Fibroblasts: A Method to Characterize the Gastrointestinal Stem Cell Niche

    Directory of Open Access Journals (Sweden)

    Agnieszka Pastuła

    2016-01-01

    Full Text Available The gastrointestinal epithelium is characterized by a high turnover of cells and intestinal stem cells predominantly reside at the bottom of crypts and their progeny serve to maintain normal intestinal homeostasis. Accumulating evidence demonstrates the pivotal role of a niche surrounding intestinal stem cells in crypts, which consists of cellular and soluble components and creates an environment constantly influencing the fate of stem cells. Here we describe different 3D culture systems to culture gastrointestinal epithelium that should enable us to study the stem cell niche in vitro in the future: organoid culture and multilayered systems such as organotypic cell culture and culture of intestinal tissue fragments ex vivo. These methods mimic the in vivo situation in vitro by creating 3D culture conditions that reflect the physiological situation of intestinal crypts. Modifications of the composition of the culture media as well as coculturing epithelial organoids with previously described cellular components such as myofibroblasts, collagen, and neurons show the impact of the methods applied to investigate niche interactions in vitro. We further present a novel method to isolate labeled nerves from the enteric nervous system using Dclk1-CreGFP mice.

  8. Comparison of two screening bioassays, based on the frog sciatic nerve and yeast cells, for the assessment of herbicide toxicity.

    Science.gov (United States)

    Papaefthimiou, Chrisovalantis; Cabral, Maria de Guadalupe; Mixailidou, Christina; Viegas, Cristina A; Sá-Correia, Isabel; Theophilidis, George

    2004-05-01

    Two different test systems, one based on the isolated sciatic nerve of an amphibian and the other on a microbial eukaryote, were used for the assessment of herbicide toxicity. More specifically, we determined the deleterious effects of increasing concentrations of herbicides of different chemical classes (phenoxyacetic acids, triazines, and acetamides), and of 2,4-dichlorophenol (2,4-DCP), a degradation product of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D), on electrophysiological parameters and the vitality of the axons of the isolated sciatic nerve of the frog (Rana ridibunda) and on the growth curve of the yeast Saccharomyces cerevisiae based on microtiter plate susceptibility assays. The no-observed-effect-concentration (NOEC), defined as the maximum concentration of the tested compound that has no effect on these biological parameters, was estimated. In spite of the different methodological approaches and biological systems compared, the NOEC values were identical and correlated with the lipophilicity of the tested compounds. The relative toxicity established here, 2,4-DCP > alachlor, metolachlor > metribuzin > 2,4-D, 2-methyl-4-chlorophenoxyacetic acid (MCPA), correlates with the toxicity indexes reported in the literature for freshwater organisms. Based on these results, we suggest that the relatively simple, rapid, and low-cost test systems examined here may be of interest as alternative or complementary tests for toxicological assessment of herbicides. PMID:15180372

  9. Release of relaxin-like gonad-stimulating substance from starfish radial nerves by lonomycin.

    Science.gov (United States)

    Mita, Masatoshi

    2013-07-01

    In starfish, the peptide hormone gonad-stimulating substance (GSS) secreted from nervous tissue stimulates oocyte maturation to induce 1-methyladenine (1-MeAde) production by ovarian follicle cells. Recently, GSS was purified from radial nerves of the starfish Asterina pectinifera and identified as a relaxin-like peptide. This study examines the mechanism of GSS secretion from radial nerves. When radial nerves isolated from A. pectinifera were incubated in artificial seawater containing ionomycin as a calcium ionophore, GSS release increased in a dose-dependent manner; 50% activity of GSS release was obtained with approximately 10 µM ionomycin. Another calcium ionophore, A23187, also stimulated GSS release from radial nerves. In contrast, membrane permeable cyclic AMP and cyclic GMP analogs failed to induce GSS release. These results suggest that GSS secretion is induced by intracellular Ca(2+) as a second messenger.

  10. Arachidonic Acid Derivatives and Their Role in Peripheral Nerve Degeneration and Regeneration

    Directory of Open Access Journals (Sweden)

    Carlos Rodrigo Camara-Lemarroy

    2012-01-01

    Full Text Available After peripheral nerve injury, a process of axonal degradation, debris clearance, and subsequent regeneration is initiated by complex local signaling, called Wallerian degeneration (WD. This process is in part mediated by neuroglia as well as infiltrating inflammatory cells and regulated by inflammatory mediators such as cytokines, chemokines, and the activation of transcription factors also related to the inflammatory response. Part of this neuroimmune signaling is mediated by the innate immune system, including arachidonic acid (AA derivatives such as prostaglandins and leukotrienes. The enzymes responsible for their production, cyclooxygenases and lipooxygenases, also participate in nerve degeneration and regeneration. The interactions between signals for nerve regeneration and neuroinflammation go all the way down to the molecular level. In this paper, we discuss the role that AA derivatives might play during WD and nerve regeneration, and the therapeutic possibilities that arise.

  11. Arachidonic Acid Derivatives and Their Role in Peripheral Nerve Degeneration and Regeneration

    Science.gov (United States)

    Camara-Lemarroy, Carlos Rodrigo; Gonzalez-Moreno, Emmanuel Irineo; Guzman-de la Garza, Francisco Javier; Fernandez-Garza, Nancy Esthela

    2012-01-01

    After peripheral nerve injury, a process of axonal degradation, debris clearance, and subsequent regeneration is initiated by complex local signaling, called Wallerian degeneration (WD). This process is in part mediated by neuroglia as well as infiltrating inflammatory cells and regulated by inflammatory mediators such as cytokines, chemokines, and the activation of transcription factors also related to the inflammatory response. Part of this neuroimmune signaling is mediated by the innate immune system, including arachidonic acid (AA) derivatives such as prostaglandins and leukotrienes. The enzymes responsible for their production, cyclooxygenases and lipooxygenases, also participate in nerve degeneration and regeneration. The interactions between signals for nerve regeneration and neuroinflammation go all the way down to the molecular level. In this paper, we discuss the role that AA derivatives might play during WD and nerve regeneration, and the therapeutic possibilities that arise. PMID:22997489

  12. Optic Nerve Pit

    Science.gov (United States)

    ... Conditions Frequently Asked Questions Español Condiciones Chinese Conditions Optic Nerve Pit What is optic nerve pit? An optic nerve pit is a ... may be seen in both eyes. How is optic pit diagnosed? If the pit is not affecting ...

  13. Nerve lesioning with direct current

    Science.gov (United States)

    Ravid, E. Natalie; Shi Gan, Liu; Todd, Kathryn; Prochazka, Arthur

    2011-02-01

    Spastic hypertonus (muscle over-activity due to exaggerated stretch reflexes) often develops in people with stroke, cerebral palsy, multiple sclerosis and spinal cord injury. Lesioning of nerves, e.g. with phenol or botulinum toxin is widely performed to reduce spastic hypertonus. We have explored the use of direct electrical current (DC) to lesion peripheral nerves. In a series of animal experiments, DC reduced muscle force by controlled amounts and the reduction could last several months. We conclude that in some cases controlled DC lesioning may provide an effective alternative to the less controllable molecular treatments available today.

  14. Activated protein C modulates the proinflammatory activity of dendritic cells

    Directory of Open Access Journals (Sweden)

    Matsumoto T

    2015-05-01

    Full Text Available Takahiro Matsumoto,1,2* Yuki Matsushima,1* Masaaki Toda,1 Ziaurahman Roeen,1 Corina N D'Alessandro-Gabazza,1,5 Josephine A Hinneh,1 Etsuko Harada,1,3 Taro Yasuma,4 Yutaka Yano,4 Masahito Urawa,1,5 Tetsu Kobayashi,5 Osamu Taguchi,5 Esteban C Gabazza1 1Department of Immunology, Mie University Graduate School of Medicine, Tsu, Mie Prefecture, 2BONAC Corporation, BIO Factory 4F, Fukuoka, 3Iwade Research Institute of Mycology, 4Department of Endocrinology, Diabetes and Metabolism, 5Department of Pulmonary and Critical Care Medicine, Mie University Graduate School of Medicine, Tsu, Mie Prefecture, Japan *These authors contributed equally to this work Background: Previous studies have demonstrated the beneficial activity of activated protein C in allergic diseases including bronchial asthma and rhinitis. However, the exact mechanism of action of activated protein C in allergies is unclear. In this study, we hypothesized that pharmacological doses of activated protein C can modulate allergic inflammation by inhibiting dendritic cells. Materials and methods: Dendritic cells were prepared using murine bone marrow progenitor cells and human peripheral monocytes. Bronchial asthma was induced in mice that received intratracheal instillation of ovalbumin-pulsed dendritic cells. Results: Activated protein C significantly increased the differentiation of tolerogenic plasmacytoid dendritic cells and the secretion of type I interferons, but it significantly reduced lipopolysaccharide-mediated maturation and the secretion of inflammatory cytokines in myeloid dendritic cells. Activated protein C also inhibited maturation and the secretion of inflammatory cytokines in monocyte-derived dendritic cells. Activated protein C-treated dendritic cells were less effective when differentiating