Page 3 of 5 FirstFirst 12345 LastLast
Results 21 to 30 of 42

Thread: Interesting SfN 2008 Presentations

  1. #21

    Howard Hughes Medical Institute

    I remembered some more.

    Next: Howard Hughes Medical Institute.

    Regulated release of neurotrophins by oligodendrocytes (Issa P Bagayogo)
    Recent literature suggests that oligodendrocytes (OLGs) not only myelinate cells, but also release trophic factors. For instance, brain-derived neurotrophic factor (BDNF) is expressed in OLGs and has been shown to enhance the survival and function of basal forebrain cholinergic neurons (Dai et al, J. Neuro 2003). Astrocytes, another glial cell population also express BDNF and in other studies are shown to release BDNF in a regulated manner (Society for Neuroscience 2007 conference, slide presentation # 655.2). To determine whether regulated release of BDNF also occurs in OLGs, differentiated OLG populations isolated from the cingulate and parietal cortices were stimulated with the neurotransmitter glutamate or glutamate receptor agonists to evaluate BDNF release. ELISA assays indicated that 10 minutes application of glutamate increases the amount of BDNF released by OLGs. Immunocytochemical and western blot analysis revealed that OLG lineage cells exhibit metabotropic glutamate receptors as well as ionotropic AMPA/Kainate and NMDA receptors. However, while ACPD, a metabotropic agonist, mimics the effects of glutamate on BDNF release, the ionotropic agonists kainate and NMDA do not, suggesting that AMPA/KA and NMDA receptors do not play a role in the release of BDNF in OLGs. In addition, the glutamate effect was blocked by a metabotropic antagonist, MCPG, further demonstrating that metabotropic receptors mediate glutamate actions. The PLC-pathway appears to be a key mediator of BDNF release. Short-term treatment of OLGs with the PLC activator m-3M3FBS induced robust release of BDNF. Furthermore, in the presence of PLC antagonist U73122, ACPD-induced release was completely blocked. Similar results were obtained using the IP3 inhibitor 2-APB and the intracellular calcium chelator BAPTA-AM, suggesting that intracellular calcium mobilization is required for BDNF release. Taken together, these results suggest that OLG lineage cells can secrete BDNF in a regulated manner, through the activation of metabotropic glutamate receptors and the PLC pathway.

    • Funded by:
    • NIH Grant HD23315
    • HHMI Research Training Fellowship For Medical Student 2005
    • HHMI Continued Support, Second Year of Research 2006


    Stress Inducible Protein 1 neurotrophic functions involve protein synthesis stimulation via the mTOR pathway (Glaucia Hajj)
    It is known that the control of protein synthesis is essential for neuronal development and that some neurotrophic factors, like BDNF, exert their functions through translational regulation. We have described that the co-chaperone Stress Inducible Protein 1 (STI1), promotes neuritogenesis through stimulation of the ERK1/2 pathway and protection against cell death in neurons through the activation of cAMP/PKA. Remarkably, STI1, which is a cytoplasmic protein, is secreted by astrocytes through a still unknown mechanism. The secreted STI1 is able to stimulate the phosphorylation of neuronal ERK1/2, suggesting that STI1 secretion is a physiological mechanism of promoting neuronal differentiation and survival. Because protein synthesis modulation is essential for these phenomena, we studied the ability of STI1 to control the translational machinery. The PI3K/mTOR signaling pathway is a classical regulator of the translational initiation. Interestingly, both PI3K and mTOR inhibitors abolished the neuritogenic and neuroprotective effects of STI1, suggesting that protein synthesis is a critical step for these processes. In accordance with the effect of PI3K inhibitor, AKT activation was elicited by STI1. Further confirming mTOR pathway activation, STI1 stimulated p70S6 Kinase and 4E-BP2 phosphorylation, direct targets of mTOR. p70S6K phosphorylation could be blocked by both mTOR and PI3K inhibitors. We also observed the phosphorylation of the translation initiation factor eIF4E, an ERK/MNK pathway target, upon STI1 treatment. Strikingly, STI1 increased protein synthesis in a dose dependent manner, an effect dependent on PI3K, mTOR and ERK. We then propose that STI1 could be a new neurotrophic factor that acts through regulation of the mTOR pathway.

    • Funded by:
    • FAPESP
    • HHMI
    • IBRO Travel Fellowship


    Neuronal interleukin-16 (NIL-16) exhibits nuclear translocation and is a precursor of IL-16, which signals via CD4 and p56lck and enhances neurite growth (Steven D. Fenster)
    In this study, we investigate functional parallels between pro-IL-16, a cytokine precursor expressed primarily in lymphocytes, and NIL-16, an isoform of pro-IL-16 found only in postmitoitic neurons of the hippocampus and cerebellum. In lymphocytes, cleavage of pro-IL-16 by caspase-3 yields two functionally distinct proteins: The secreted C-terminus corresponding to IL-16 functions as an immunoregulatory cytokine; whereas the remaining pro-domain translocates to the nucleus and regulates the expression of cell-cycle control proteins to induce cell-cycle arrest. In the immune system, cellular responses to IL-16 require CD4 receptors and p56lck activation. Here, we show that primary cerebellar neurons also express CD4, NIL-16 and p56lck mRNA, suggesting that neurons contain components of the known IL-16 signaling pathway. Consistent with a role for p56lck in the neuronal IL-16-signaling pathway, treatment of primary cerebellar neurons with recombinant IL-16 (500 nM) resulted in an increase in c-Fos positive neurons and this effect was inhibited by pretreatment with the p56lck inhibitor, 4-amino-6-hydroxyflavone (50 nM). For lymphocytes and other CD4-expressing cells, IL-16 functions as a chemoattractant and to modulate growth. We show that IL-16 may also modulate neurite growth: For low-density hippocampal neuronal cultures, IL-16 treatment (10-500 nM, 2-4 days in vitro) was associated with increased neurite length. Future studies will address the role of p56lck and the CD4 receptor in modulating IL-16-induced neurite outgrowth. Consistent with the possibility that NIL-16, similar to pro-IL-16, is capable of nuclear translocation, we show that NIL-16 is distributed throughout the cytoplasm when expressed in COS-7 cells; whereas following treatment with PAC-1 (800 nM), a caspase-3 activator, NIL-16 localizes to the nucleus. In neurons, caspase-3 activation was associated with enhanced cytosolic, rather than nuclear, clustering of NIL-16. Future studies will address the role of the nuclear translocation sequence and PDZ-domains in determining NIL-16 localization and the influence of NIL-16 on the expression of cell-cycle regulatory proteins, such as Skp2 and p27Kip1, known to be influenced by nuclear translocation of pro-IL-16 in lymphocytes.

    • Funded by:
    • HHMI 2004 Undergraduate Science Education Program


    A model for neuronal competition during development (Nikhil Sharma)
    We report that developmental competition between sympathetic neurons for survival is critically dependent on a sensitization process initiated by target innervation and mediated by a series of feedback loops. Target-derived nerve growth factor (NGF) promoted expression of its own receptor TrkA in mouse and rat neurons and prolonged TrkA-mediated signals. NGF also controlled expression of brain-derived neurotrophic factor and neurotrophin-4, which, through the receptor p75, can kill neighboring neurons with low retrograde NGF-TrkA signaling whereas neurons with high NGF-TrkA signaling are protected. Perturbation of any of these feedback loops disrupts the dynamics of competition. We suggest that three target-initiated events are essential for rapid and robust competition between neurons: sensitization, paracrine apoptotic signaling, and protection from such effects.

    • Funded by:
    • Woodrow Wilson Undergraduate Research Fellowship (N.S.)
    • NIH fellowship NS053187 (C.D.D.)
    • NIH grants NS34814 (D.D.G.)
    • NIH grants EY016281 (E.N.)
    • HHMI (D.D.G.)
    ...it's worse than we thought. it turns out the people at the white house are not secret muslims, they're nerds.

  2. #22

    Texas

    Next: Texas.

    Modulation of Notch signaling enhances CNS myelination in aggregate cultures (Hisami Koito)
    Myelination is essential for the development and function of the nervous system in vertebrates. Dysfunction of myelin or myelin-forming oligodendrocytes (OLs) in the CNS contributes to many neurological deficits associated with, for example, multiple sclerosis, cerebral palsy, schizophrenia, and Alzheimer’s diseases. However, the molecular mechanisms that control CNS myelination remain poorly understood. To address the question how CNS myelination is initiated and regulated, we developed an in vitro CNS myelination system in which cell aggregates prepared from rat E16 forebrains were co-cultured with oligodendrocyte precursors. The CNS cell aggregates were composed of progenitors of neurons, astrocytes and OLs, and were cultured in a serum-free medium for up to 4 weeks. Radial growth of axons was evident after 1 or 2 days in culture (DIV) and was extensive around 2 weeks. Glial progenitors migrated out of the aggregates and gradually differentiated into OLs and astrocytes over the course of culturing. Exogenous OL precursors were added to the aggregate cultures at DIV 10 to increase the number of OLs. Many OL processes aligned with axons and started to ensheath axons at DIV 18-22. Using this system, we examined the effect of several neurotrophic factors that have been reported previously to promote myelination. Both ciliary neurotrophic factor and leukemia inhibitor factor markedly promoted OL differentiation and survival but only moderately increased myelin formation. In contrast, γ-secretase inhibitor DAPT did not promote OL survival and differentiation, but significantly increased the population of ensheathing OLs and enhanced myelination in a concentration-dependent manner. Notch signaling has been implicated in regulating OL development and is subjected to γ-secretase regulation. The Notch ligand contactin/F3 appears to promote OL differentiation whereas Jagged1 inhibits OL differentiation. To examine whether DAPT promotes myelination by blocking the Notch signaling, the effect of soluble contactin1 and Jagged1 was studied. While contactin1 significantly increased the number of internodes, Jagged1 had no effect. Combination of contactin1 and DAPT resulted in further increases in myelin formation. These data suggest that modulation of Notch signaling pathways may provide a new strategy for promoting CNS myelination and myelin repair.

    • Funded by:
    • Startup Fund from Texas A&M University


    Microfluidic co-culture platform for studying cns axon-glia interaction (Jaewon Park)
    A circular design microfluidic compartmentalized co-culture platform that can be used for axon-glia interaction research has been fabricated by polydimethylsiloxane (PDMS) softlithography. The PDMS co-culture platform is composed of one open compartment for neuronal soma (soma compartment) and one closed co-centric ring compartment (axon/glia compartment) for axons and oligodendrocytes (OLs). Two compartments are connected through arrays of shallow microfluidic channels that function as axon-guiding structures as well as a physical barrier between the compartments. This allows only axons to cross the microchannels and form axonal network layer inside the axon/glia compartment, thus OLs loaded into the axon/glia compartment interact only with axons but not with dendrites or neuronal somata. Primary cortical neurons were cultured in the soma compartment for two weeks prior to the loading of OLs into the axon/glia compartment to allow axons to form extensive networks inside the axon/glia compartment. Cells were then co-cultured for two additional weeks. The microfluidic device showed successful fluidic isolation between the two compartments. The separation of neuronal cell bodies and dendrites from axons growing through the arrays of microchannels into the axon/glia compartment was verified by immunocytochemical labeling of cells. The proposed circular design showed excellent cell loading capability near the axon-guiding microchannels that increased the number of axons crossing the channels as well as excellent cell viability. More than 79 % of the axon/glia compartment was covered with axons after four weeks of culture. OLs cultured on top of the axonal networks interacted extensively with axons and differentiated rapidly into mature OLs. This novel microfluidic co-culture device will provide a significant technical improvement in studying CNS axon-glia interaction in vitro and offer a potential high-throughput screening platform for drug candidates that promote myelin repair.

    • Funded by:
    • Start up funds from Texas A&M University
    ...it's worse than we thought. it turns out the people at the white house are not secret muslims, they're nerds.

  3. #23

    Cooling, OPC

    Cooling, OPC.

    An electrophysiological characterisation of acute and chronic post-injury changes following spinal cord contusion injury in the adult rat (Meirion Davies)
    Spinal cord injury is a major neurological problem that often leads to permanent impairments in locomotor function. However, in humans and animal models, there is generally a period of limited, spontaneous functional recovery that occurs in the first few weeks following injury. Little is known about the physiological changes that occur during this period, and understanding these will be important for future studies aimed at enhancing or recapitulating spontaneous repair processes in a chronic spinal cord injury. Here, we attempt to characterize some of these changes. We have developed the novel technique of teased root functional axon counts to investigate the electrophysiological changes that occur over the acute post-injury phase in a clinically relevant model of spinal injury. Adult rats underwent a thoracic spinal cord contusion injury using the Infinite Horizons contusion device and were assessed for functional improvements, behaviourally and electrophysiologically, at 1, 2 and 4 weeks post-injury. We demonstrate that over the first month following injury, an increasing number of axons spared by the injury conduct across the lesion, with a concomitant increase in their conduction velocities. We also report positive correlations between locomotor performance and electrophysiological outcomes following injury. Finally, with the use of cooling, we present evidence for the existence of viable, possibly demyelinated, axons that are not conducting at physiological temperatures. Our findings are consistent with both ion channel redistribution and remyelination as the mechanisms underlying the recovery of conduction. We are currently applying these techniques to chronic contusion injuries. These results demonstrate the presence of viable but non-conducting spared axons following contusion injury which could represent an important population for therapeutic targeting.

    • Funded by:
    • Medical Research Council


    Exogenous LIF stimulates oligodendrocyte progenitor cell proliferation and remyelination in vivo (Benjamin E Deverman)
    The development of therapies that enhance the repair capabilities of the adult brain by stimulating the proliferation of endogenous neural stem and progenitor cells and/or directing their subsequent differentiation into functional neurons and glia is a relatively neglected area of current stem cell research. We have found that injection of an adenovirus expressing leukemia inhibitory factor (LIF) into the adult brain promotes neural stem cell (NSC) self-renewal and stimulates the proliferation oligodendrocyte progenitor cells (OPCs). Based on these findings, in particular the effect of LIF on OPCs, we hypothesized that if LIF could enhance the OPC response in the context of chronic demyelination it may, in turn, promote the generation of new oligodendrocytes and aid remyelination. To test this, we have been feeding mice a diet containing cuprizone for 12 weeks, a course of treatment that induces demyelination in the corpus callosum (CC), hippocampus, and cortex, and injecting the mice with either a LIF- or lacZ-expressing adenovirus (Ad-LIF or Ad-lacZ) in the lateral ventricle. Three weeks after adenovirus injection and removal of cuprizone from the diet, mice that received Ad-LIF exhibit an increase in the number of proliferating OPCs in the demyelinated hippocampus. Many of these OPCs survive and differentiate so that by 6 weeks after removal of cuprizone, the number of mature oligodendrocytes in LIF-treated mice is restored to near normal numbers in the CA3 region of the hippocampus, where LIF-induced Stat3 activation is the greatest. Remarkably, remyelination in the CA3 region is more extensive in LIF-treated mice and is accompanied by the reformation of nodal, paranodal, and juxtaparanodal domains on a subset of axons. Our findings that LIF can promote oligodendrocyte generation and remyelination in vivo taken together with its known ability to protect oligodendrocytes from death in the EAE model of MS, as well as following spinal cord injury, suggest that LIF has multiple activities that could be of therapeutic benefit for demyelinating diseases.

    • Funded by:
    • B. Deverman is supported by a fellowship from CIRM
    • National Institute of Neurological Disorders and Stroke


    Reactivated astrocytes in the contused spinal cord inhibit oligodendrocyte differentiation of adult oligodendrocyte precursor cells by increasing the expression of bone morphogenetic proteins (Xiaoxin Cheng)
    Promotion of remyelination is an important therapeutic strategy to facilitate functional recovery after traumatic spinal cord injury (SCI). Transplantation of neural stem cells or oligodendrocyte precursor cells (OPCs) has been used to enhance remyelination after SCI. However, the microenvironment in the injured spinal cord is inhibitory for oligodendrocyte (OL) differentiation of NSCs or OPCs. Identifying the inhibitory signaling for OL differentiation in the injured spinal cord could lead to new therapeutic strategies to enhance remyelination and functional recovery after SCI. In the present study, we examined the effects of reactive astrocytes from the injured spinal cord on OL differentiation of adult OPCs since gliosis is one of the dramatic changes after SCI. OPCs were purified from adult rat spinal cord by immunopanning with the O4 antibody. OPCs were co-cultured with astrocytes purified from the adult rat normal spinal cord (NSC) or injured spinal cord at 1 week (ISC1w) and 1 month (ISC1m) after contusion, respectively. After differentiation for three days, the percentage of O1+ OLs or GFAP+ astrocytes was significantly decreased and increased, respectively, from OPCs co-cultured with ISC1w- or ISC1m-astrocytes compared the control or NSC-astrocytes. Conditioned medium (CM) from ISC1w- and ISC1m-astrocytes also significantly inhibited OL differentiation of OPCs with concurrent promotion of astrocytes differentiation compared to NSC-astrocyte CM or control basal differentiation medium. Expression of bone morphogenetic protein (BMP) 2 and 4 was dramatically increased in ISC1w- or ISC1m-astrocytes. The concentration of BMP in CM of ISC1w- or ISC1m-astrocytes was also significantly increased. Application of noggin, a BMP receptors antagonist, rescued OL differentiation and blocked astrocyte differentiation of OPCs which were inhibited and induced by CM of ISC1w- or ISC1m-astrocytes, respectively. Our results confirmed that upregulated BMP2 and 4 in the active astrocytes are major inhibitors for OL differentiation of OPCs after SCI, suggesting that manipulation of BMP signaling in the endogenous or grafted NSCs or OPCs may be a useful therapeutic strategy to increase their OL differentiation and remyelination and enhance functional recovery after SCI.

    • Funded by:
    • NIH R01 NS061975
    • RR15576
    • KSCHIRT


    Interferon-gamma induces cell death of oligodendrocyte progenitor cells in injured spinal cord (Junichi Ito)
    Therapeutic approaches to acute spinal cord injury have been attempted to preserve neurons and glial cells from the secondary injury which is partially mediated by various inflammatory cytokines. In addition to mature cells in adult spinal cord, it has been reported that there are many oligodendrocyte progenitor cells (OPCs) reacting to the insults and that those cells have potential to restore the damaged tissue. Since these OPCs may also be susceptible to detrimental effects of inflammatory cytokines, here we examined cytokine-mediated cell death in OPCs population in injured spinal cord.
    Adult rats received a contusion injury produced by IH impactor (150 kdyn) at level of Th9 and the endogenous proliferating OPCs were labeled with GFP-carrying retrovirus that was injected to parenchyma two days after injury. The specimen of 7 days post-injury (dpi) revealed a significant decrease in the number of GFP-labeled NG2 expressing cells (proliferating OPCs) compared with the specimen of 4 dpi, indicating that those cells fell into cell death. To identify the cytokine that is responsible for cell death of OPCs, we performed in vitro cell survival assay. Various inflammatory cytokines, such as tumor necrosis factor-alpha, interleukin-1beta and interferon-gamma (IFNg), were applied to CG-4 cell culture (OPC cell line) and we found that IFNg was most potent to induce cell death within 48 hr incubation. Western blotting of the cell culture showed time-dependent increase of cleaved-caspase 3 expression in IFNg treated cells, suggesting that IFNg-induced cell death is mediated by apoptosis.
    To evaluate the significance of IFNg-induced cell death in spinal cord injury, first we examined expression of IFNg in mice spinal cord injury model and found IFNg was induced in injured cord with its peak at 14 dpi. Then, we utilized IFNg receptor deficient mice (IFNgR-/-) and create moderate thoracic spinal cord injury (IH impactor 60 kdyn) to those mice and control C57BL/6J mice. The endogenous OPCs are labeled by BrdU i.p. injection from 0 dpi to 2 dpi and specimens were collected on 7 dpi for histological evaluation. There were more BrdU positive glial progenitor remaining in IFNgR-/- goup compared with wild type mice and functional motor score of hind limbs were statistically better in the mutant mice.
    Taken together, we assume that the elevation of IFNg in injured spinal cords induces cell death in proliferating OPCs. The improvement of functional motor score in IFNgR-/- may be attributed partially to the better survival of OPCs and partially to other effects of IFNg. We propose that blockade of IFNg signaling could be a new therapeutic approach for acute spinal cord injury.

    • Funded by:
    • KAKENHI17300190
    ...it's worse than we thought. it turns out the people at the white house are not secret muslims, they're nerds.

  4. #24

    Chronic

    Promising chronic presentations not yet listed.

    Behavioral effects after preparation of a chronic cervical spinal contusion injury in preparation for delayed peripheral nerve grafting and application of Chondroitinase ABC (Harra R Sandrow)
    A previous study from our lab demonstrated that manipulating the contused cervical (C) spinal cord one week or one month after injury and apposing one end of a peripheral nerve graft (PNG) did not produce further functional impairment. Axons from the injured cord grew into the graft, but because the graft was not intended to aid in recovery, the distal end was left unapposed. As an advancement of this study the effects of two types of PN grafts on recovery of function in a chronic unilateral C5 contusion injury model were examined. After aspiration of cavity debris the lesion area was treated with glial-cell line-derived neurotrophic factor (GDNF) prior to grafting to enhance axonal growth. The first grafting approach used a pre-degenerated PN segment to span the lesion cavity 8 weeks after injury, followed by microinjection of chondroitinase ABC (ChABC) rostral and caudal to the site. The second approach used a PN segment to bridge a C5 contusion injury with an acute C7 dorsal quadrant lesion that had been treated with ChABC. There was a 3 week delay between apposition of proximal and distal ends of the PNG. Behavioral testing of each group was initiated 2 days following the C5 unilateral contusion and continued biweekly for 8 weeks to determine whether the deficit created was consistent among groups. Two days after the grafting surgery, behavioral testing resumed and is currently in progress for an eight week post grafting period. Functional recovery is being assessed with the forelimb locomotor scale (FLS) and BBB for the ipsilateral hindlimb. TreadScan is being used to measure gait parameters quantitatively. Grid-walk is a sensorimotor test used to measure the percentage of correct foot placements during a short period of time and the grooming test qualitatively grades the range of motion by the affected forelimb. There were no significant differences between groups in the FLS, BBB, grid and grooming among groups prior to the grafting surgery. All tests displayed an initial deficit 2 days or 1 week post injury followed by spontaneous recovery that plateaued by week 4 post SCI. Analysis of performance after the graft and ChABC microinjections is underway. The results of this study will go a long way towards defining the functional efficacy of a combination of treatments applied to a chronic injury situation.

    • Funded by:
    • NIH Grant NS26380


    In vivo imaging of sensory axons regenerating from PNS to CNS (Alessandro DiMaio)
    Intraspinal regeneration of adult sensory axons is primarily impeded at the dorsal root entry zone (DREZ) but the mechanisms remain unclear. To improve our understanding of these mechanisms, we have used a widefield fluorescence microscope and a confocal microscope for imaging dorsal root axons of Thy1-YFP transgenic mice (YFP-H: Feng et al., 2000). In YFP-H, ca. 150 neurons are fluorescently labeled in each dorsal root ganglion (DRG) and the labeled primary afferent axons are dispersed among unlabeled ones. YFP+ neurons are among the largest of DRG neurons, positive for RT-97 and negative for Calcitonin Gene Related Peptide (CGRP) staining. Imaging YFP+ axons after crushing a L5 rootlet in PNS (ca. 3mm away from DREZ), we found that responses of YFP+ axons to crush injury are generally uniform: 1) dying back of axons lasts for 1-2 days, 2) axons initiate their growth typically as one sprout, 3) axons extend ca. 1mm per day forming no lateral branches, 4) growing tips of extending axons are tapered in a spindle shape. Many axons fail to grow across the crush site. Nonetheless, these axons did not seem to be particularly ‘poor’ regenerators, as indicated by numerous but directionless sprouts continuously forming from such axons. We also found that axons reaching CNS area did not stop their extension exactly at the DREZ (defined as the boundary between astrocytes and Schwann cells). Indeed, preliminary analysis of the imaged axons and surrounding glial cells in wholemount preparations of spinal cords indicates that axons frequently extend along astrocytic processes but stop on contact with oligodendrocytes. We are continuing our analysis of the interactions between the imaged axons and glial cells in detail, and imaging chronic responses of axon tips and their dynamics at the DREZ. Time-lapse in vivo imaging should provide an unprecedented opportunity to understand why sensory axons fail to grow into CNS, providing important insights into strategies for improving intraspinal regeneration.

    • Funded by:
    • NIH NS 45091
    • VA Medical Research Service


    Role of reactive gliosis and analysis of Nerve Growth Factor treatment in a neuropathic pain rat model (Michele Papa)
    Neuropathic pain is a chronic debilitating condition characterized by lancinating or continuous burning-type pain, and typically associated with the occurrence of allodynia and/or hyperalgesia. In this study, we investigated the activity of NGF on inflammatory and neuronal markers in the spinal cord and the behaviour in a spared nerve injury (SNI), a model of neuropathic pain in the rat. Seven days after SNI, allodynic and hyperalgesic behaviour was investigated respectively by Von Frey filament test and thermal Plantar test. Rat recombinant NGF (125 ng/microL/h) or artificial cerebro spinal fluid (control group) was administered by intrathecal continuous infusion device (Alzet pump) for seven days on lumbar enlargement of spinal cord, a third group received recombinant NGF for seven days followed by a seven days CSF. NGF treated animals, one week later showed reduced allodynia and thermal hyperalgesia compared to control group. Molecular and morphological analysis were performed on lumbar spinal cord, and segments of the injured and naive sciatic nerve. Image computer assisted analysis of the expression of IBA-1 for microglial cells; S100beta, GFAP as macroglial markers; NeuN and GAD75 as neuronal markers; GLT and Glyt1 as glial transporters markers, PARPP and Edu as markers of death and cell division respectively were measured in the spinal cord of treated and control animals. In NGF treated animals expression of both neuronal markers NeuN and GAD75 compared to controls revealed a net increase. A net reduction of microglial Iba1 and macroglial GFAP expression in NGF treated animals compared to controls. NGF treatment induced a net increase of both glial transporters GLT and Glyt1. The interruption of NGF treatment determined a revert of all values. In conclusion, we hypothesize that NGF results critical in maintaining neurochemical homeostasis in the spinal cord of nociceptive neurons, and that supplementation may be beneficial in restoring and/or maintaining analgesia in chronic pain conditions.

    • Funded by:
    • Associazione Levi Montalcini


    Human umbilical cord blood stem cells mediate the upregulation of matrix metalloproteinase-2 in rats after spinal cord injury (Krishna Kumar Veeravalli)
    Matrix metalloproteinases (MMPs) play diverse roles in the spinal cord. The beneficial effects obtained by blocking MMPs with their inhibitors during the initial days after spinal cord injury (SCI) are lost when the treatment is extended to periods of wound healing and tissue remodeling. The ability of MMPs to support or inhibit normal cellular functions and participate in secondary pathogenesis likely depends on when and where MMPs are expressed and their overall activity. Stem cell therapy using human umbilical cord blood (hUCB) stem cells, which repair and replace damaged or lost cells, provides much promise for the treatment of SCI. Hence, in the present study, we aimed to investigate the regulation of several MMPs during the acute and chronic phases after SCI in rats as well as the changes in their regulation after treatment with hUCB. We also investigated the regulation of MMP-2, a dominant gelatinase expressed during wound healing, after injury and the changes in its expression/activity after treatment with hUCB in injured rats and in vitro in injured spinal neurons. Quantitative real-time PCR data, western blot analysis, gelatin zymography and immunohistochemical analysis of the spinal cord sections from control, injured and hUCB-treated rats revealed that hUCB treatment upregulated MMP-2 levels during the recovery phase following spinal cord injury. Immunocytochemical analysis and gelatin zymography revealed similar results in vitro when spinal neurons and co-cultures of spinal neurons and hUCB were injured with staurosporine and hydrogen peroxide. Based on the in vivo and in vitro evaluations performed in the present study, we conclude that treatment with hUCB increases MMP-2 levels during wound healing or the recovery phase following spinal cord injury in rats. The ability of hUCB to incorporate into the injured spinal cord and to increase MMP-2 levels in the injured cord during wound healing provides promise for the future treatment of patients with spinal cord injury.

    • Funded by:
    • NIH Grant CA75557, CA92393
    • NIH Grant CA95058, CA116708
    • NIH Grant NS47699, NS57529
    • NIH Grant NS61835
    • Caterpillar, Inc, OSF St. Francis, Inc.


    Human mesenchymal stem cells promote the functional recovery of rats with spinal cord injury (Jia-Wei Lin)
    Severe spinal cord injuries (SCI) often result in paraplegia or quadriplegia. Up to now, there are still no satisfactory therapeutic agents or strategies for treating SCI patients. In recent years, evidence indicates that stem cell therapy provides some hope for treating SCI. This study aimed to investigate the effect of immediate or delayed application of human mesenchymal stem cells (hMSCs) on the functional recovery of rats with spinal cord injury. We randomly assigned adult female Sprague-Dawley rats into the SCI + Vehicle group, and SCI + hMSCs group. Spinal cord injury was induced at the T10 of spinal cord by a force of 200 kdynes generated using an IH Impactor. Animals in the SCI + Vehicle group received vehicle injections into the lesion site immediately or 4 weeks after SCI. Animals in the SCI + hMSCs group received implantation of hMSCs into the lesion site immediately or 4 weeks after injury. The functional recovery of SCI rats was evaluated for 3 months using the BBB rating scale. Our results indicated that both immediate and delayed implantation of hMSCs into the lesion site promoted the functional recovery of SCI rats. Our findings strongly support the idea that stem cell therapy is an encouraging strategy for treating acute or chronic SCI.

    • Funded by:
    • Grant NSC 96-2320-B-038-022 (LYY)
    • ITRI Grant 95-TMU-IAC-050 (LYY)


    Effect of whole body chronic intermittent magnetic field exposure on nociceptive and non-nociceptive behavior in complete spinal cord injured rats (Suneel Kumar)
    A complete transection of spinal cord leads to irreversible motor paralysis, areflexia & sensory loss in the limbs below the level of injury, chronic pain and loss of bladder/bowel functions along with an increased susceptibility to respiratory and heart problems. Magnetic field (MF) is reported to increase 5-HT turnover, reduced pain, improved bladder/bowel control and promotes peripheral nerve regeneration. In the present study, we investigated the possible effect of chronic intermittent MF (17.96 μT, 50 Hz, 2d X 8 wks) exposure on nociceptive (hot plate test) and non-nociceptive responses (acetone test) in clinically relevant rat model of complete paraplegia. The SCI (at T13) was performed under ketamine anesthesia (60 mg/kg) on adult male Wistar rats (200-250 g) in accordance with the rules and regulations of Institutional Ethical Committee concerning the use and care of laboratory animals. They were divided into sham (n=7), SCI (n=8) and SCI + MF (n=8) group. Latency of paw withdrawal in the hot plate test decreased significantly at post-SCI wk 6 (p=0.04) and wk 8 (p=0.01) as compared to sham group whereas no change was observed in SCI+MF group over the period of 8 weeks. There was a significant increased in latency at wk 8 (p=0.001) in SCI+MF as compared to SCI group. In SCI group, there was a significant increase in behavioral scores of acetone test over the observation period of 8 wks (p=0.0001) whereas, in SCI+MF group, there was an increase till wk 4 (p=0.0001) and then the score decreased significantly (p=0.0001) as compared to SCI group. Bladder function starts improving from post-SCI day 10 and becomes fully functional at post-SCI day 21 in SCI group. In SCI+MF group, bladder function starts improving from post-SCI day 6 and becomes fully functional at post-SCI day 10. BBB scoring, done to observe locomotor recovery also indicated the facilitatory effect of MF exposure. On histological examination, cavities/tissue damage was found to be less in SCI+MF as compared to SCI group.
    The results suggest a significant recovery from post-SCI hypersensitivity and of bladder function by magnetic field exposure in spinal cord injured rats.

    • Funded by:
    • DST-196


    NADPH-d and Fos reactivity in the rat spinal cord following experimental spinal cord injury (hemisection) and embryonic neural stem cell transplantation (Gulgun Kayalioglu)
    In this study, the role of nitric oxide (NO) in neuropathic pain and the effect of embryonic neural stem cell (ENSC) transplantation on NO content in spinal cord neurons were investigated by administration of NO donor L-arginine and NO synthase inhibitor L-NAME in rats after spinal cord injury (SCI) as well as in rats with ENSC transplantation. For this purpose, 3 groups of Sprague-Dawley rats were used (n=30 each): control grup (laminectomy), SCI (hemisection at T12-T13 segment) and SCI + ENSCT. Animals were treated with L-NAME (75mg/kg/ip) and L-arginine (225 mg/kg/ip) 2 h before perfusion for acute and for 28 days daily for chronic groups and with physiological saline for acute and chronic control groups. Fos-immunohistochemistry and NADPH-d histochemistry were performed in spinal cord segments rostral and caudal to the injury site. Tail-flick latency time increased in both acute and chronic L-NAME groups and increased in acute and decreased in chronic L-arginine groups. The number of Fos-labelled neurons decreased in acute and chronic L-NAME and decreased in acute L-arginine groups. Following ENSC, the number of Fos labeled neurons did not change in acute L-NAME, but decreased in the chronic L-NAME groups. Fos-immunoreactive neurons decreased in acute and chronic L-arginine groups. The number of NADPH-d-reactive neurons decreased in acute L-NAME and increased in L-arginine groups with and without ENSC. In chronic L-NAME groups, the number of NADPH-d reactive neurons decreased in animals with and without ENSC, this decrease being more sigificant in animals with ENSC transplantation (p<0.05 and p<0.01, consequently). The results of this study confirms the role of NO in neuropathic pain and shows an improvement following ENSC transplantation, observed as a decrease in the number of Fos-immunoreactive (nociceptive) and NADPH-d-reactive (NO containing) spinal neurons in spinal cord segments rostral and caudal to SCI.

    • Funded by:
    • TUBITAK (Scientific and Technological Research Council of Turkey) Grant SBAG104S330


    Functional Electrical Stimulation (FES) decreases cell proliferation after spinal cord injury (Jurate Lasiene)
    Functional Electrical Stimulation (FES) is a clinical therapy used to restore limb and organ function as well as to treat pain and prevent sore formation resulting from spinal cord injury (SCI) and other neurological disorders. An artificial source provides targeted muscles with the electrical stimulation needed to elicit a contractile response. Beneficial motor and sensory behavior effects have been demonstrated with FES treatment; however neural correlates and changes in the CNS have never been explored. In the present study we describe the effects of FES on proliferation, distribution, and phenotypic fate of dividing cells after spinal cord injury. C57/Bl6 mice either 84 weeks (chronic) or 9 days (acute) after moderate T9 contusion injury had electrodes surgically implanted in the vastus lateralis muscle group bilaterally (2 per muscle) and stimulated with an EMS-6500 portable stimulator at 50 Hz, on/off pulses, every 2 seconds for 2 one-hour periods (morning and evening) each day for 14 days. Age-matched SCI controls and FES animals received daily BrdU (5-bromo-2-deoxyuridine) injections for 14 days and were sacrificed one day after the injections were completed. BrdU+ cells were counted using the fractionator method at 1mm intervals 5mm caudal and rostral to the lesion epicenter. We observed different patterns of cell proliferation for chronic and acute animals. Proliferating cells in acute FES and control animal cords were in Gaussian distribution with most mitotic cells concentrated at the lesion epicenter while in chronic SCI cords BrdU+ cells were about equally distributed along the extent of the cord. Both acute and chronic FES animals demonstrated a considerable drop in proliferating cells throughout the cord. In addition, there were significantly fewer BrdU+ cells in chronic vs. acute conditions. Most BrdU+ cells were found to be Olig2+, while less than 7% were S100B+ and less than 1% were GFAP+. Despite cellular changes we did not observe significant behavioral changes as judged with Basso Mouse Scale (BMS). Currently, we are evaluating the proportion of the cells positive for microglial marker Iba-1. We are also analyzing the extend of serotonergic (5-HT) and calcitonin gene related peptide (CGRP) fiber branching. We conclude that FES surprisingly reduces glial progenitor proliferation after SCI without significantly affecting progenitor commitment to astrocytic lineage.

    • Funded by:
    • NIH R01 NS46724-01A1
    • IRP foundation
    ...it's worse than we thought. it turns out the people at the white house are not secret muslims, they're nerds.

  5. #25

    Whoa!

    This deserves a post of its own. Thank you, Canada!

    Pre-clinical and clinical development of a drug treatment for Central Pattern Generator (CPG) activation and 'reflex' stepping induction (Pierre Guertin)
    Since 2001, we mainly focused on developing a technological platform aimed at efficiently screening and identifying molecules that are capable of CPG activation and ‘reflex’ stepping generation in vivo. That platform is composed on a spinal cord-transected (Tx) mouse model, a standardized protocol with no stimuli that may modify the results and increase variability (no weight support, no tail/perineal pinching, no training), and a sensitive approach (ACOS, Spinal Cord 43, 2005) to ease quantitative assessment of drug-induced leg movements in Tx mice (reviewed in, J Neurosci Res, in press). A plethora of serotonergic, glutamatergic, adrenergic and dopaminergic ligands were tested over the years. Although, a few drugs were found to induce locomotor-like movements (LM - rhythmic flexions and extensions involving at least one joint), none were capable to generate weight-bearing stepping per se. Based upon some earlier in vitro and in vivo work (e.g., Neurosci Lett 358, 2004), we began testing drug combinations. Combining some of our best leads led to the discovery of a powerful cocktail capable of inducing full weight-bearing stepping during 45 min in untrained/non-stimulated Tx mice (manuscript in prep). Administered 3X/wk for 5 wks, this patent protected cocktail called Spinalon displayed evidence of safety and preliminary evidence of utility (e.g., robust locomotor effects, partially restoration of serum lipid profile, immune cell count and muscle size after 5 wks). Ongoing tests are currently assessing fully efficacy/utility of regular treatments in Tx mice. The 1st pilot test in patients was done recently. A monoplegic man who received (p.o.) Spinalon every 2 days for 2 wks showed no atypical side effects providing 1st preliminary evidence of safety in men (Spinal Cord, in press). Other patients in Canada and Morocco were recently recruited. The 1st multi-center trials (PI/IIa) is expected for Q4-2008. If safety data are found, subsequent trials will aim at clearly determining efficacy (PIIb-rhythmic EMGs/stepping/cycling) and utility in Multiple Sclerosis and motor-complete SCI patients (PIIb-III-prevention of secondary health complications).

    • Funded by:
    • CIHR
    • FRSQ
    • IFP
    ...it's worse than we thought. it turns out the people at the white house are not secret muslims, they're nerds.

  6. #26
    The Canadian guys are also working on ejaculation!

    If the Spinalon works this could be awsome, not a cure but could be great for therapy and general well being. And possibly it could be functional as longs as you can initiate when you want the CPG to kick in.

    http://www.neurospinathera.com/pipeline2a.html

  7. #27
    good work
    Han: "We are all ready to win, just as we are born knowing only life. It is defeat that you must learn to prepare for"

  8. #28

    Promising

    Thanks everyone. I'm back with more promising presentations.

    Transplantation of mesenchymal stem cells and olfactory ensheathing glia improves functional recovery in rats by sparing the spinal cord tissue after a contusion lesion (Takashi Amemori)
    Stem and progenitor cells from various sources are currently recognized as having considerable potential for the treatment of spinal cord injury (SCI). Mesenchymal stem cells (MSCs) can improve functional outcome in rats with SCI by producing trophic factors and cytokines. Olfactory ensheathing glia (OEG) can facilitate regeneration following SCI by providing guiding strands and molecules of the extracellular matrix for axonal ingrowth. In our study, MSCs and OEG were transplanted together to examine their additive and synergistic effects on SCI. MSCs were isolated from the femurs and OEG were obtained from the lamina propria of the olfactory mucosa of 4-week-old Wistar rats. As a model of SCI, a balloon compression lesion at level 8-9 of the thoracic vertebra was used in adult male Wistar rats weighing 270-330g. MSCs and/or OEG (300,000 cells) were implanted into the lesion one week after SCI (MSCs and OEG, n=14; MSCs alone, n=16; OEG alone, n=15); the control group (n=12) was injected only with saline. Hindlimb locomotor activity was assessed weekly by the BBB test for two months. All transplanted groups recovered their hindlimb gait sufficiently to support their weight (BBB scores: MSCs and OEG, 9.18 ± 0.43; MSCs alone, 8.94 ± 0.42; OEG alone, 9.30 ± 0.46), but the control animals never showed any weight support by their hindlimbs (BBB score: 7.08 ± 0.24). Morphometric measurements of the lesions (an area 2 mm long) showed a similar increase in spared white matter volume in all three transplanted groups when compared with control rats. The increase in spared gray mater was higher in MSC-grafted rats when compared to OEG-grafted and control animals. Although animals transplanted with MSCs or OEG alone showed significant differences in the BBB test as well as in the volume of the spared white and grey matter compared to controls, no significant differences were found in the results of the BBB test and the volume of the spared white matter between the transplanted groups. We can conclude that both MSCs and OEG have the ability to improve motor activity by sparing the white and gray matter, but their co-transplantation does not provide additional benefits compared to the transplantation of MSCs or OEG alone.

    • Funded by:
    • AVOZ50390703
    • LC554
    • 1M0538
    • 1A8697-5
    • GACR309/1246

    Intrathecal IgG delivery enhances behavioural recovery and promotes axonal sparing following moderately severe cervical spinal cord injury (Sherri L Robins)
    Spinal cord injury (SCI) is a devastating condition that can be accompanied by high levels of morbidity and mortality, while also severely reducing the quality of life to affected individuals. Current treatment options for clinicians and patients offer a low degree of efficacy and are often accompanied by undesirable complications, making the development of novel, clinically relevant therapeutic strategies a necessary goal. The inflammatory response to SCI is highly complex and dynamic, contributing to both secondary injury mechanisms and wound repair pathways. It has proven difficult to target the deleterious aspects of the inflammatory response, while at the same time preserving or accentuating the beneficial elements. Using a moderately severe clip compression injury model in adult female Wistar rats, the objective of this study was to evaluate the inflammatory and neuroprotective effects of delayed intrathecal delivery of IgG following SCI. At either 0, 8 or 24 hours after a C7-T1 35g clip compression injury, a subarachnoid catheter was inserted at the site of injury and a mini-osmotic pump containing either IgG or BSA in saline was implanted under the animal’s skin, delivering the IgG or BSA for 7 days. Animals for Western Blot and real-time PCR analysis of immune cell infiltration and levels of inflammatory mediators were sacrificed at 7 days, while long term behavioural and neuroanatomical observations were carried out over a six week time line. BBB open field scoring, inclined plane assessment, neuropathic pain testing and FluroGold retrograde labelling of brain stem nuclei were used to evaluate the neuroprotective effects of IgG treatment. A significant improvement in behavioural recovery and neuroanatomical preservation was observed with both 8 and 24 hour post-injury delayed IgG treatment, as compared to BSA controls. It is postulated that IgG treatment offers beneficial immune modulating effects such as altering inflammatory cell activity and cytokine expression that contribute to its neuroprotective effects. Given the clinically valid time line of administration in this study and the current clinical use of IgG to treat various neuropathies, these findings show the potential for IgG administration to be a valid and translatable therapeutic strategy for SCI patients.

    • Funded by:
    • Krembil Chair in Neural Repair and Regeneration
    • PSI Foundation Grant


    352.Spinal Cord: Therapeutic Strategies II.

    Combining polymer scaffolds seeded with neurotrophin-3 overexpressing human neural stem cells and matrix modification by chondroitinase ABC promote recovery of motor function and enhance axonal regrowth in the hemisected thoracic Spinal Cord (Dong Hoon Hwang)
    We have previously shown that implantation of polymer scaffolds seeded with human neural stem cells (hNSCs) genetically modified to secrete neurotrophin-3 (NT3-hNSCs) promote recovery of motor function and enhance motor evoked potentials of contralateral gastrocnemius after spinal cord injury (SCI). Transplanted NT3-hNSCs contained within the scaffold survived well and frequently migrated to the adjacent host spinal cord. However, axonal growth through the scaffold could not be achieved. We hypothesized that chondroitin sulfate proteoglycans (CSPGs) at the scaffold-host tissue interface could be a barrier to the migration of grafted cells and severely restrict axonal growth through the scaffold. The present study aimed to assess the effects of digestion of CSPGs on migration of grafted NT3-hNSCs, axonal growth, and recovery of motor function following SCI. Multiporous polycaprolactone (PCL, MW 2000) sponge seeded with NT3-hNSCs was implanted after T7 hemisection injury. Either penicillinase or chondroitinase ABC was continuously infused at the implantation site with an Alzet 2004 osmotic pump. The longest extent of migration was increased by chondroitinase ABC by 5-fold compared to animals with control penicillinase infusion. The enzymatic digestion of CSPGs induced outgrowth of growth associated protein-43 (GAP-43) positive fibers into the PCL scaffold. Chondroitinase treatment improved the quality of open field locomotion and accuracy of hindlimbs placement on grid walk. We also examined recovery of transcranial magnetic motor evoked potential (MMEP). The hemisection injury completely abolished MMEP responses in both hindlimbs. Only contralateral MMEPs were recovered in the animals with implantation of PCL with NT3-hNSCs combined with penicillinase. In contrast, eighty percent of the rats with chondroitinase treatment showed successful recovery of both hindlimbs MMEPs. These results indicate that the application of chondroitinase enhanced the therapeutic benefits of PCL scaffold seeded with NT3-hNSCs. A successful strategy for spinal cord repair sould be a combination of multiple approaches including adequate scaffold, NSCs, growth factors, and modification of extracellular matrix. Our study demonstrates feasibility and efficacy of the combinatorial strategy.

    • Funded by:
    • the 21st Century Frontier Research Fund of the Ministry of Science & Technology (SC-3111), Republic of Korea.
    • the Korea Research Foundation Grant (KRF-2006-311-E00439)


    Sustained delivery of thermally stabilized chABC after spinal cord injury promotes axonal sprouting (Hyun-Jung Lee)
    Chondrotin sulfate proteoglycans (CSPGs) are upregulated and accumulate around the lesion site after spinal cord injury (SCI), and are major inhibitors of regeneration. To overcome CSPG-mediated inhibition, modification or digestion of CSPGs with chondroitinase ABC (chABC) has been explored. ChABC digests glycosaminoglycan chains on CSPGs and enhances sprouting and regeneration when delivered to the lesion site. However, chABC has a crucial limitation; it is thermally unstable and at 37ºC, its enzymatic activity is significantly attenuated within 72 hours1. Therefore multiple or continuous infusions with an indwelling catheter are necessary to maintain enzymatic functionality for periods of 2 weeks or longer and, are invasive and clinically problematic. Here, to overcome these limitations, we enhanced the thermal stability of chABC by adding a protein stabilizer, trehalose, and demonstrated that chABC maintained its enzymatic activity for 4 weeks at 37 ºC in vitro.
    Next, using dorsal over hemisection injury at T10 in adult rats, thermally stabilized chABC was delivered by a minimally invasive hydrogel scaffold2 carrying chABC loaded lipid microtubules at the lesion site immediately following injury. To determine effectiveness of topical delivery of thermally stabilized chABC, animal groups treated with single injection/gel scaffold implantation of chABC, chABC/trehalose and penicillinase were included as controls. Two weeks after surgery the enzymatic functionality of released chABC was examined by CS-56, WFA and 3B3 imuunostaining. Axonal sprouting was examined by NF160 and 5-HT immunostaining.
    The results demonstrated that- a) thermal stability of enzymatic activity of chABC was greatly enhanced; b) thermally stabilized chABC was successfully delivered slowly and locally without a catheter; c) released chABC was effective in vivo, and significant differences of CSPG digestion were observed; and d) axonal sprouting was enhanced in the animal groups treated with chABC-gel scaffold. We suggest that significant improvement of the thermal stability and delivery effectiveness of chABC could be combined with other therapies or agents to treat SCI.
    Acknowledgment to NIH R01 NS043486
    1. Tester NJ, Plaas AH & Howland DR. J Neurosci Res 85(5):1110-8 (2007).
    2. Jain A, Kim YT, McKeon RJ & Bellamkonda RV. Biomaterials 27:497-504 (2006).

    • Funded by:
    • NIH R01 NS043486


    Implantation of polymer scaffolds with NT-3 secreting human neural stem cells improves locomotor recovery following canine spinal cord injury (Young Mi Kang)
    Stem cell-based cell therapy holds promise to enhance functional recovery following spinal cord injury (SCI). Most evidence that transplantation of neural stem cells can produce beneficial outcomes after SCI has been derived from rodent models. Before being translated to human patients, it would be needed to examine the therapeutic effects in larger animal models where weight-bearing locomotion should be much more challenging. The present study tested whether a combinatorial strategy centering on human neural stem cells (hNSCs) improves locomotor function in a canine hemisection SCI model. We sought to enhance therapeutic efficacy by ectopic expression of NT-3 in the hNSCs. Polymer scaffolds were implanted to facilitate the delivery of hNSCs and bridge the large lesion cavity. NT-3 overexpressing hNSCs (F3.NT3) were produced by retroviral transduction of the immortalized hNSC line (F3) with human NT-3 cDNA. F3.NT3 cells were seeded into a predesigned poly(lactic-co-glycolic acid)(PLGA 65:35) scaffolds, and the PLGA scaffolds with hNSCs (PLGA-F3.NT3) were implanted immediately after left hemisection at T11 in female dogs weighing 20-30 kg. The PLGA scaffold seemed to nicely fill the lesion cavity, showing a varying degree of biodegradation by 12 weeks. Dogs with PLGA-F3.NT3 showed significant improvement in the quality of hindlimbs locomotion compared to the animals with control animals (SCI only or implantation of PLGA only). Survival of grafted cells was confirmed at 2 weeks, and some of the grafted cells migrated out to the contralateral white matter. In contrast, we could not detect surviving hNSCs in any of the animals at 12 weeks. Implantation of PLGA-F3.NT3 was associated with a decrease in the deposition of chondroitin sulfate proteoglycans along the interface between the residual spinal cord and scaffolds. There were very few regenerating axons into the scaffold in both groups. However, the ventral horns caudal to the hemisected region were more profusely innervated by serotonergic axons in animals with PLGA-F3.NT3. These findings raise a possibility that implantation of PLGA-F3.NT3 can produce beneficial motor outcomes by promoting axonal remodeling below the lesion. This study suggests that the therapeutic strategy combining multidisciplinary approaches can be feasible and effective for spinal cord repair in larger species.

    • Funded by:
    • This work was supported in part by the 21st Century Frontier Research Fund of the Ministry of Science & Technology (SC-3111)


    Neural differentiation of transplanted allogenic umbilical cord blood-derived stem cells in acute spinal cord injury model dogs (Ohkyeong Kweon)
    Regeneration of central nervous system is highly limited after injury. Recently, cell transplantation therapy with adult mesenchymal stem cells (MSCs) has been regarded as a good therapeutics for regenerative medicine. These obtained cells can differentiate into the neuronal phenotypes in ischemic or damaged brain and spinal cord. It was reported that improvement of limb function of spinal cord injured dogs was demonstrated by transplantation of mesenchymal stem cells from canine cord blood (cUCB-MSCs) [Lim, J. H., Byeon, Y. E., Ryu, H. H., Jeong, Y. H., Lee, Y. W., Kim, W. H., Kang, K. S., Kweon, O. K. Transplantation of canine umbilical cord blood-derived mesenchymal stem cells in experimentally induced spinal cord injured dogs. J Vet Sci 2007;8:275-282]. There is no study on the neural differentiation of cUCB-MSC in vivo.
    Ten s were injected into SCI site. bbbbbbbbeagle dogs were used (7.41 ± 0.85 kg). The extradural compression of spinal cord was performed using the balloon catheter for 12 hours. All the dogs showed hind limb paralysed after compression. cUCB-MSC were produced by culture and proliferation of mononucleated cells and characterization by FACS analysis. In the all group, GFP labeled lenti-viral vector inserted stem cells were injected into the site of spinal cord injury (SCI). Dogs were assigned, randomly, into five groups, two dogs every group, according to the duration after cell transplantation; 4 days, 1week, 2 weeks, 4 weeks and 8 weeks. At all timepoint, we traced the cUCB-MSC injected immunohistochemically. Behavioral assessment was performed to evaluate functional recovery of the hind limbs by using the 15-point scoring system (Olby score). MR images were obtained.
    Olby scores increased from 0 at the treatment to 3.67 at 2 weeks after treatment, 5.5 at 4 weeks and 8.5 at 8 weeks, respectively. The hyperintense lesion in T2W sagittal plane of MRI is larger than histological lesion at 4 and 7 days but the sizes became similar between hyper intense and histological lesions after 4 weeks. GFP labeled lenti-viral vector inserted stem cells were positive with GFAP, NF160, Tuj-1, Nestin, MAP2 and oligodendrocyte in injured lesion. It means that cUCB-MSC implanted differentiated into nerve cells astrocyte, neuron and oligodendrocyte.
    In conclusion, functional improvement after transplantation of cUCB-MSC were observed in acute SCI model dogs. Immuno-fluorescence staining showed the differentiation of cUCB-MSC into nerve cells. It was suggested that neural differentiation of cUCB-MSC transplanted might play a role for the improvement of neurological function of SCI dogs.

    • Funded by:
    • BK21 Program for Veterinary Science and Seoul R&BD Program 10548


    Behavioral effects after preparation of a chronic cervical spinal contusion injury in preparation for delayed peripheral nerve grafting and application of Chondroitinase ABC (Harra R Sandrow)
    A previous study from our lab demonstrated that manipulating the contused cervical (C) spinal cord one week or one month after injury and apposing one end of a peripheral nerve graft (PNG) did not produce further functional impairment. Axons from the injured cord grew into the graft, but because the graft was not intended to aid in recovery, the distal end was left unapposed. As an advancement of this study the effects of two types of PN grafts on recovery of function in a chronic unilateral C5 contusion injury model were examined. After aspiration of cavity debris the lesion area was treated with glial-cell line-derived neurotrophic factor (GDNF) prior to grafting to enhance axonal growth. The first grafting approach used a pre-degenerated PN segment to span the lesion cavity 8 weeks after injury, followed by microinjection of chondroitinase ABC (ChABC) rostral and caudal to the site. The second approach used a PN segment to bridge a C5 contusion injury with an acute C7 dorsal quadrant lesion that had been treated with ChABC. There was a 3 week delay between apposition of proximal and distal ends of the PNG. Behavioral testing of each group was initiated 2 days following the C5 unilateral contusion and continued biweekly for 8 weeks to determine whether the deficit created was consistent among groups. Two days after the grafting surgery, behavioral testing resumed and is currently in progress for an eight week post grafting period. Functional recovery is being assessed with the forelimb locomotor scale (FLS) and BBB for the ipsilateral hindlimb. TreadScan is being used to measure gait parameters quantitatively. Grid-walk is a sensorimotor test used to measure the percentage of correct foot placements during a short period of time and the grooming test qualitatively grades the range of motion by the affected forelimb. There were no significant differences between groups in the FLS, BBB, grid and grooming among groups prior to the grafting surgery. All tests displayed an initial deficit 2 days or 1 week post injury followed by spontaneous recovery that plateaued by week 4 post SCI. Analysis of performance after the graft and ChABC microinjections is underway. The results of this study will go a long way towards defining the functional efficacy of a combination of treatments applied to a chronic injury situation.

    • Funded by:
    • NIH Grant NS26380


    Feasibility of dynamic entrainment with ankle mechanical perturbation to treat human locomotor deficits (Jooeun Ahn)
    Despite advances in cellular and molecular therapies, sensory-motor training is required to assist recovery after neurological injury such as stroke or spinal cord injury (SCI). Human-interactive robots can deliver sensory-motor treatment safely and numerous studies have shown their effectiveness for upper-limb therapy. To treat the lower extremity, we introduced Anklebot, a machine that can simultaneously apply ankle torques in plantar/dorsi-flexion and inversion/eversion. Here, we describe initial attempts to explore how it might be used for locomotion therapy and contrast it to the approach of most current therapeutic robots for locomotion.
    Though it is generally accepted that a central pattern generator (CPG) underlies mammalian locomotion, much of the coordination required to walk emerges from the natural gravito-inertial dynamics of the limbs. As Anklebot was carefully designed to allow the expression of natural dynamics, we tested whether it might be applied to assist the recovery of dynamic walking, possibly recruiting and entraining residual CPGs in the lumbar cord. Analysis indicated that, with suitable control, Anklebot can offset the essential energy loss due to foot-ground collision and stabilize the limit cycle underlying sagittal-plane locomotion. It may simultaneously assist lateral (frontal-plane) balance. Difficult to train on a treadmill, this is an essential component of normal locomotion, especially important during turns.
    To test whether Anklebot could entrain the locomotor limit-cycle in practice, in a pilot experiment, we perturbed the gait of unimpaired human subjects by applying torque to the ankle at various frequencies. With a properly designed perturbation, 8 subjects out of 10 exhibited entrained gaits: they adapted their gait frequencies and synchronized their ankle actuation with the mechanical perturbation supplied by the robot. Entraining human gait with periodic torque from a robot may provide an approach to walking therapy that is uniquely supportive of normal biological function. Based on a patient’s performance, a robot may entrain the patient’s walking frequency and gradually “drag” it towards a normal walking frequency. By controlling robotic torque frequency and amplitude, assistance may be adjusted continuously to promote patient participation, an essential element of successful upper-extremity neuro-restoration. This is difficult to accomplish with most current robots for locomotor therapy, which impose limb kinematic patterns. Moreover, this dynamic approach may be able to promote recovery with minimal involvement of supraspinal input, especially important for rehabilitation after SCI.

    • Funded by:
    • Samsung Scholarship
    • New York State Center of Research Exellence, CO19772
    • Eric P. and Evelyn E. Newman Fund


    Passive exercise alters stretch reflex properties in rats with spinal cord transection (M. K Garrison)
    Objective: Spasticity or a hyper-excitable stretch reflex (SR) is one of the major motor impairments causing patients with spinal cord injury (SCI) to locomote abnormally, and treatments that reduce spasticity have been linked to improved gait in humans with SCI. This study examined the effects of passive exercise on the SR in a rat transection model of SCI. A novel approach using a windup protocol was used to quantify the changes in spasticity post transection as well as to distinguish the effects of passive exercise on the SR.
    Methods: Sixteen adult Sprague-Dawley rats were divided into two experimental groups. After a T10 spinal transection, 8 animals underwent daily passive exercise to the hind limbs and 8 animals were untreated. SRs were tested weekly. A rapid, 600 deg/sec, repeated stretch (10 repetitions at 1, 2.5, and 4 Hz) was applied to the ankle by a custom built actuator. The torque and electromyographic (EMG) responses to these imposed perturbations were measured and used as the dependent variables.
    Results: While involuntary motor responses to the imposed stretch were noted in some animals as early as week one, a windup response to the repeated stretches was not consistently present until week 7 in the transection only animals. Windup was significant at all frequencies for EMG and at 1 and 2.5 Hz for torque. At 2.5Hz, peak plantar flexion torque demonstrated a 2-fold increase and gastrocnemius peak EMG a 5-fold increase over the first stretch. The passive exercise group showed a trend toward windup over weeks 3-5 but this was absent by week 7. Retention testing in this group, after stopping exercise for 3 weeks, revealed the presence of windup at levels similar to the non-exercised animals.
    Conclusions: Windup of the SR in transected rats emerges by 7 weeks post transection. Six weeks of daily passive exercise was found to eliminate the windup of the SR in the exercise group. These effects were plastic as a return of the windup was evidenced after cessation of exercise for 3 weeks. These data are consistent with the findings of H-reflex changes in transected rats following a passive exercise program. The novel windup protocol used in this study provides a minimally invasive means for longitudinal assessment of spasticity.

    • Funded by:
    • NIH Grant # P20 RR-16460 from the IDeA Networks of Biomedical Research Excellence (INBRE) Program of the National Center for Research Resources
    • NCRR award RR20146 to the Center for Translational Neuroscience


    A new assessment method of transplanted Schwann cell viability in the spinal cord by co-transplanting two different protein-tag marker expressing cells (Shinya Hoshikawa)
    Transplantation of Schwann cells (SC) is one approach to spinal cord repair that could potentially enhance the growth and myelination of endogenous axons. However, Poor survival of cells transplanted into the CNS is a widespread problem and limits their therapeutic potential. Therefore, we hypothesized that gene transfer of anti-apoptotic proteins such as Bcl-2 families to the transplanted SC could suppress their apoptotic cell death after grafted into injured spinal cord. One of the obstacles to examining such hypothesis is the difficulty in comparing rats received control SC with candidate gene transferred SC due to limited reproducibility of transplantation procedures. In order to avoid this problem, we designed a novel approach so that we could compare control cells with experimental cells in the same tissue specimen.
    We prepare retrovirus expressing Bcl-xL and a protein-tag DsRed and control retrovirus expressing other protein-tag, EGFP. Using pMX-PREP retrovirus vector, gene-transduced SC could be selected by puromycin. SC were infected with either of retrovirus in vitro separately and purified by puromycin selection. We transplanted gene-transduced SC into a one-week-old moderately contused adult rat thoracic spinal cords. To assess the survival of transplanted gene-transduced SC, DsRed-Bcl-xL expressing SC were “co-transplanted” together with the same number of only EGFP expressing SC (control). Histological analysis one week after transplantation revealed that DsRed-Bcl-xL expressing SC were observed more frequently than control cells at the grafting site. These results suggest that
    overexpression of Bcl-xL enhanced cell survival in the case of SC transplantation into the injured spinal cord. It appears that overexpression of Bcl-xL in the transplanted SC may lead to new therapeutic approaches of spinal cord injury. In conclusion, we demonstrate that 1) co-transplantation of two different protein-tag marker expressing SC is an efficacious new method for assessment of transplanted cell viability, 2) overexpression of Bcl-xL in the transplanted SC enhanced cell survival in injured spinal cord.

    • Funded by:
    • Grant-in-Aid for Scientific Research of The Ministry of Education,Culuture,Sports,Science and Technology


    Effect of whole body chronic intermittent magnetic field exposure on nociceptive and non-nociceptive behavior in complete spinal cord injured rats (Suneel Kumar)
    A complete transection of spinal cord leads to irreversible motor paralysis, areflexia & sensory loss in the limbs below the level of injury, chronic pain and loss of bladder/bowel functions along with an increased susceptibility to respiratory and heart problems. Magnetic field (MF) is reported to increase 5-HT turnover, reduced pain, improved bladder/bowel control and promotes peripheral nerve regeneration. In the present study, we investigated the possible effect of chronic intermittent MF (17.96 μT, 50 Hz, 2d X 8 wks) exposure on nociceptive (hot plate test) and non-nociceptive responses (acetone test) in clinically relevant rat model of complete paraplegia. The SCI (at T13) was performed under ketamine anesthesia (60 mg/kg) on adult male Wistar rats (200-250 g) in accordance with the rules and regulations of Institutional Ethical Committee concerning the use and care of laboratory animals. They were divided into sham (n=7), SCI (n=8) and SCI + MF (n=8) group. Latency of paw withdrawal in the hot plate test decreased significantly at post-SCI wk 6 (p=0.04) and wk 8 (p=0.01) as compared to sham group whereas no change was observed in SCI+MF group over the period of 8 weeks. There was a significant increased in latency at wk 8 (p=0.001) in SCI+MF as compared to SCI group. In SCI group, there was a significant increase in behavioral scores of acetone test over the observation period of 8 wks (p=0.0001) whereas, in SCI+MF group, there was an increase till wk 4 (p=0.0001) and then the score decreased significantly (p=0.0001) as compared to SCI group. Bladder function starts improving from post-SCI day 10 and becomes fully functional at post-SCI day 21 in SCI group. In SCI+MF group, bladder function starts improving from post-SCI day 6 and becomes fully functional at post-SCI day 10. BBB scoring, done to observe locomotor recovery also indicated the facilitatory effect of MF exposure. On histological examination, cavities/tissue damage was found to be less in SCI+MF as compared to SCI group.
    The results suggest a significant recovery from post-SCI hypersensitivity and of bladder function by magnetic field exposure in spinal cord injured rats.

    • Funded by:
    • DST-196

    Functional recovery after spinal cord injury in mice through activation of microglia and dendritic cells following IL-12 administration (Shigeki Ohta)
    We have previously reported that thetransplantation of dendritic cells (DCs) brings about functional recovery after spinal cord injury (SCI) in mice through the activation of endogenous microglia/macrophages and neural stem/progenitor cells. In this study, the effect of interleukin-12 (IL-12), which is secreted from DCs, was evaluated for the treatment of SCI in mice. Administration of IL-12 into the injured site significantly increased the number of activated microglia/macrophages and DCs as well as the expression of brain-derived neurotrophic factor (BDNF) surrounding the lesion site. Immunohistochemical analyses showed that de novo neurogenesis and remyelination were induced by IL-12 treatment. Furthermore, an open field test using Basso-Beattie-Brenham (BBB) scoring revealed a significant improvement of locomotor function in mice treated with IL-12. These results suggest that IL-12 administration into the injured spinal cord results in a functional recovery through the activation of microglia/macrophages and DCs.

    • Funded by:
    • KAKENHI18500299


    Respective roles of 5-HT1A and 5-HT7 receptors in the promoting action of 8-OH-DPAT on locomotor recovery after spinal cord transection in rodents (Florence Cotel)
    Complete transection of the spinal cord at mid-thoracic level induces a loss of locomotor activity in hind limbs. Although both descending and ascending pathways are definitively disrupted, previous studies showed that locomotor movements of hind limbs can be promoted by appropriate treatments of spinal animals (cats, rats, mice). This "spinal locomotion" supports the idea that lumbar spinal cord contains a neuronal network able to generate the muscular locomotor pattern (the so-called Central Pattern Generator for locomotion - CPG). A key element in the process of recovery is the stimulation of specific monoaminergic receptors, notably some 5-HT receptors involved in modulatory control of spinal neurons and CPG network. In the rat, reinnervation of the lumbar spinal cord by 5-HT fibers and terminals from transplanted embryonic raphe neurons promoted recovery of typical locomotor rhythmic movements of hind limbs (Orsal et al., Prog Brain Res 137:213-30, 2002). This effect of locally released 5-HT could be mimicked by chronic treatment with the agonist 8-OH-DPAT (daily injections at 0.25 mg/kg during at least one month; Antri et al., Eur J Neurosci 18:1963-72, 2003). Because 8-OH-DPAT is known to act as a mixed agonist of both 5-HT1A and 5-HT7 receptors, our aim was to investigate whether only one or both of these receptor types mediate its locomotor promoting effect in spinal rats and mice. For that, we assessed the capacity to induce locomotor recovery of one month chronic treatment with 8-OH-DPAT injected once a day) when 5-HT1A receptors were inhibited or absent, in three conditions: 1) in adult spinal rats, treatment (0,25 mg/kg/day) preceded or not by daily ip injections of a specific 5-HT1A receptor antagonist (WAY 100635 at the daily dose 0,25 mg/kg 2) in adult spinal rats continuously treated with WAY 100635 delivered from an osmotic minipump; 3) in adult spinal 5-HT1A-/- mice (Sv129) (8-OH-DPAT: 0,44 mg/kg/day, recalculated dose adapted to mice according to the size principles). Direct assessment of the possible role of 5-HT7 receptors in 5-HT-induced recovery of hind limb locomotion in spinal animals is currently underway using selective 5-HT7 receptor antagonists and 5-HT7-/- mutants.

    • Funded by:
    • ANR (Agence Nationale pour la Recherche)
    • IRME/FRM (Institut pour la Recherche sur la Moelle epinière et l'Encéphale)


    Injury-induced differential expression of chondroitin sulphate proteoglycans in two spinal cord regions with distinct growth-inhibitory properties (Laurent Christian Waselle)
    Robust axonal growth and guidance by both attractive and repulsive cues is required to establish selective neuronal connectivity during development. In the adult, stable fibre patterns are necessary to maintain normal CNS function. This is in part achieved by the presence of chondroitin sulphate proteoglycans (CSPGs), extracellular matrix molecules that are widely expressed throughout the developing and adult CNS. Following CNS injury, CSPGs are increased at the site of the lesion and are thought to contribute to the lack of functional recovery by restricting CNS regeneration and plasticity. In vitro studies have previously demonstrated the potential of CSPGs to prevent neurite outgrowth. Furthermore, we have recently provided the first direct in vivo evidence for the contribution of the CSPGs Neurocan and Brevican to regeneration failure in the dorsal root entry zone (DREZ) following dorsal root injury. In the dorsal root lesion model, sensory axons regenerate through the peripheral dorsal root, but stop growing when they reach the DREZ. This lesion leads to a glial reaction and to disintegration of axons and myelin sheaths (Wallerian degeneration) downstream of the lesion, i. e. in the DREZ and dorsal column (DC) of the spinal cord. Recent studies in the rat indicate that the DC is less inhibitory to axonal growth after injury than the DREZ. In view of these results, we used the laser capture microdissection technology to harvest the DREZ and DC regions after dorsal root lesion, followed by RNA purification, amplification by multiplex-PCR, and temporal and quantitative analysis of mRNA expression by real-time PCR to identify transcripts preferentially expressed in the DREZ. Our results show that Neurocan mRNA expression is increased from 12 hours to 15 days post-lesion in both regions, whereas Brevican, Versican V1 and Versican V2 are only increased in the DREZ and not the DC. This indicates that these latter proteoglycans may be key molecules rendering the DREZ highly non-permissive. The development of therapeutic strategies to selectively decrease the expression of CSPGs by RNA interference and/or inhibit their synthesis, may provide novel tools to promote CNS regeneration and repair following spinal cord or brachial plexus injury.

    • Funded by:
    • Swiss National Science Foundation
    • Novartis Foundation
    • IRP Foundation
    • NCCR "Neural Plasticity and Repair"
    ...it's worse than we thought. it turns out the people at the white house are not secret muslims, they're nerds.

  9. #29

    Promising

    More:

    Peripheral nerve grafts and aFGF after spinal cord hemisection promoting recovery of lower limb functions in nonhuman primates (Chaolin Ma)
    Our work aimed to develop a novel approach in treating spinal cord injured subjects. Two monkeys received spinal cord hemisection surgeries. One of them, as a control, received only right unilateral surgical hemi-section at the T8 spine level (5 mm gap). Another one, as a treatment, in addition to the same surgery as the first monkey, was transplanted of 4 sural nerve segments to the injured spinal cord site to provide structural support and stimulate nerve re-growth. A fibrin-based mixture, containing nerve aFGF was used to stabilize the peripheral nerve grafts and fill the damage site. Both monkeys received exercise training and physical therapy after spinal cord surgery. They were also trained to perform bipedal locomotion on a motorized treadmill. Functional performance, muscle control and motorcortex activities were evaluated to assess the effect of the novel treatment strategy. The preliminary results showed that the control subject, without the repair treatment, lost his ability to move his lower limbs (the left leg due to secondary injury), with no EMG signals present in either leg and no functional recovery observed after three months. For the second monkey who received the repair, functional recovery started to appear in the third week with a significant qualitative improvement in muscle control and locomotion ability started in 10 weeks. These preliminary results showed a great potential for an effective spinal cord repair and injury treatment.

    • Funded by:
    • Taipei Veterans General Hospital


    Mesenchymal stem cells for the treatment of spinal cord injury in adult rat: effect on functional recovery and endogenous progenitor cells (Renaud Quertainmont)
    Ependymal and sub-ependymal cells are known to be neural progenitors in adult spinal cord and thus represent an interesting source of endogenous stem cells to recruit after spinal cord injury. On the other hand, it has been shown that mesenchymal stem cells (MSC) are able to differentiate into neural cells and to express the neural stem cell marker Nestin under specific conditions.
    The first aim of our work is to study the effect of a transplantation of MSC on the recruitment, stimulation of proliferation and differentiation of ependymal/sub-ependymal cells, in a model of thoracic spinal cord compression injury. We will also compare the effects of two different phenotypes of MSC (the one expressing Nestin and the one negative for Nestin), and follow the fate of these transplanted cells, as well as their effect on axonal regeneration and locomotor recovery.
    In this optic, the spinal cord of adult female Wistar rats was injured, using the micro-balloon compression model. One week after injury, rats received intraveinous injection of cultured BrdU pre-labelled MSC. Control animals received culture medium only or were not injected. In order to label the ependymal cells, the fluorescent lipophilic marker DiI was injected in the two lateral ventricules seven days before injury. Control rats received daily intra-peritoneal injection of BrdU during 3 days in order to label proliferating endogenous cells after injury. Locomotor recovery was regularly assessed using BBB and placing response tests. Animals were sacrificed 28 days after injury. Spinal cords were processed for several immunofluorescent stainings in order to determine the fate and proliferation of both ependymal progenitors and transplanted MSC.
    Our first results show a beneficial effect of the transplantation of MSC/nestin + on functional recovery. After injury, we demonstrated an important cell proliferation in the lesion site and in ependymal cells (Ki67 staining), that gradually decreases after 7 days. However, BrdU ependymal cells were still present 28 days after injury, confirming that these cells proliferate following an injury. Nestin expression increased around the ependymal canal and decreased after 7 days. These Nestin expressing cells seem to have a glial phenotype as they co-express GFAP.
    Our results confirm the presence of immature cells around the ependymal canal and the proliferating capacity for these cells after injury. They also demonstrate the beneficial effect of MSC transplant on locomotor recovery after compression lesion. Ongoing work is focused on further characterization of transplanted cells, and their possible fusion with endogenous ependymal cells.

    • Funded by:
    • European 6th Research Framework Programme, Rescue (FP6


    Systemic administration of ghrelin inhibits apoptotic cell death followed improvement of functional recovery after spinal cord injury (Jeeyoun Lee)
    Traumatic spinal cord injury (SCI) induces massive cell death leading to permanent neurological deficits, and no satisfactory treatment is currently available. Recent evidence indicates that ghrelin, an endogenous ligand for the GH secretagogue receptor, exerts neuroprotective effects in hypothalamic neuronal cells during oxygen-glucose deprivation. In addition, administration of ghrelin significantly reduced infarct volume and apoptosis of hippocampal and cortical neurons after ischemia/reperfusion in rat. In this study, we examined the protective effect of ghrelin on apoptotic cell death and functional recovery after SCI. Rats received a moderate, weight-drop contusion injury to the spinal cord and were treated with the vehicle or ghrelin (80 μg/kg) immediately after SCI and then treated with the vehicle or ghrelin at a same dose every 6 h for 1 day. Ghrelin treatment significantly improved functional recovery after SCI as determined by the Basso-Beattie-Bresnahan locomotor open field test, inclined plane test, grid walk and foot print analysis. Administration of ghrelin also reduced the lesion size at 35 days after SCI when compared to vehicle-treated controls. In addition, myelin and axonal loss after SCI were significantly inhibited by ghrelin treatment. Furthermore, ghrelin treatment inhibited neuron and oligodendrocyte apoptosis by inhibition of caspase-3 activation after SCI, and these effects were mediated by ghrelin receptor (GHSR-1a). These results suggest that ghrelin may represent a potential therapeutic agent for acute SCI in humans.

    • Funded by:
    • Korea government (MOST) M1041200011-07N1200-01110
    • Seoul R & BD Program 10524
    • Post BK21 Program


    Aerobic training during inpatient rehabilitation from cervical SCI: Program development and feasibility (Amira E Tawashy)
    Literature addressing the need for people with spinal cord injury (SCI) to adopt habitual exercise as part of a healthy lifestyle is abundant. However, no aerobic training guidelines exist for individuals undergoing inpatient rehabilitation. Further, despite their increased risk of cardiovascular disease, little research has targeted individuals with tetraplegia. This is particularly concerning given the well known disruption to sympathetic cardiovascular control following cervical level SCIs. This abstract addresses both the development and the preliminary feasibility results of an aerobic exercise program for individuals undergoing inpatient rehabilitation from motor-complete, cervical SCIs.
    We developed a circuit class that 1) increased heart rate and 2) minimized muscle fatigue (thereby facilitating aerobic activity). Six timed activity stations (including arm ergometry, boxing, sliding motion, and wheeling) were performed two-three times/week. Both exercise duration and exercise intensity gradually increased over the 3 month program. (1) Duration: Activity stations initially consisted of three minutes exercise followed by two minutes rest (18 cumulative minutes or exercise) and gradually increased to 4.5 minutes exercise followed by 30 seconds of rest (27 cumulative minutes of exercise). (2) Intensity: Target work rates (heart rate as determined from initial VO2 peak tests and/or corresponding level on Borg RPE scale) were initially set to 50%HR reserve (10-12 on the Borg RPE scale) and increased to 70%-80%HRR (16-18 on the Borg RPE scale).
    Three subjects (injury level: C5, C6, and C8; age:21, 23 and 48 years) have participated in the program thus far. Within one month, subject 1 (injury level: C5) was able to complete 21 cumulative exercise minutes, and subjects 2 and 3 (injury levels: C6, C8 respectively) were able to complete 27 cumulative exercise minutes. Average exertion over the session reached: Subject 1: 94%HRR (average 107bpm), Subject 2: 54 %HRR (average 110bpm), and Subject 3: 71%HRR (average 130bpm).
    Preliminary results suggest that despite setbacks common to inpatient rehabilitation from cervical SCI (e.g. illness, exhaustion, low mood), individuals can sustain an intense aerobic training program. Further, participants can maintain target work rates without over-bearing fatigue or compromised participation in daily rehabilitation.

    • Funded by:
    • Canadian Institute for Health Research (for career scientist award to JJE)
    • Michael Smith Foundation for Health Research (for career scientist award to JJE)


    HP012 inhibits apoptotic cell death of neuron and oligodendrocyte and improves functional recovery after spinal cord injury (Youn J Moon)
    Spinal cord injury (SCI) causes a permanent neurological disability and inflammation has been known to play an important role in the pathogenesis after injury. In inflammatory processes, microglia are activated and produce a variety of pro-inflammatory factors such as tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), cyclooxygenase-2 (COX-2) and reactive oxygen species (ROS) including nitric oxide (NO), which leads to neuronal and oligodendroglial apoptosis. In this study, we examined the neuroprotective effect of HP012, an extract of flavonoids from Scutellaria Baicalensis Georgi, after SCI. Using primary microglia, HP012 treatment significantly inhibited the expression of LPS-induced inflammatory mediators such as TNF-α, IL-1β, COX-2, and iNOS. Furthermore, ROS production including NO was significantly attenuated by HP012 treatment. To examine the neuroprotective effect of HP012 after SCI, rats were received a moderate contusion injury at T9 spinal cord and administered orally with HP012 at a dose of 100 mg/kg beginning at 2 h after injury and then further administered once a day for 2 weeks. HP012 significantly inhibited apoptotic cell death of both neuron and oligodendrocyte, and improved functional recovery after SCI. In addition, HP012 reduced the size of lesion cavity, extents of loss of axon and myelin at 35 days after SCI. Also, HP012 inhibited the expression of proinflammatory cytokines and protein carbonylation by ROS after SCI. Taken together, our data showed that HP012 significantly inhibited apoptotic cell death by inhibiting inflammation and oxidative stress after injury and the possibility that HP012 can be used as a potential therapeutic agent for acute SCI.

    • Funded by:
    • Korea government (MOST) M1041200011-07N1200-01110
    • Seoul R & BD Program 10524
    • Post BK21 Program


    GDNF modifies astrogliotic responses at graft-host interfaces allowing robust axonal regeneration into Schwann cell-seeded guidance channels grafted into hemisected adult rat spinal cords (Ling-Xiao Deng)
    Previously, we reported that glial cell line-derived neurotrophic factor (GDNF) enhanced axonal regeneration and myelination when co-administered within Schwann cell (SC)-seeded guidance channels implanted into a T9 hemisected spinal cord (Iannotti et al. Exp Neurol. 183:379-393, 2003). However, the mechanism by which GDNF mediates such effects remained unclear. Here we report that the GDNF effect on axonal growth may result from, at least in part, modifications of reactive astrocytes making these cells changing their properties from regenerative inhibitory to regenerative facilitative. We found that transplantation of guidance channels containing lenti-virus transfected SCs over-expressing GDNF promoted robust axonal regeneration into the graft environment, compared to non-GDNF treated control in this model. Moreover, GDNF-treatment smoothed the graft-host interfaces resulting in a significant decrease of reactive gliosis at these interfaces. Remarkably, GDNF treatment promoted migration of host astrocytes into the graft environment and these cells lined up longitudinally along regenerative axons implying that the migrated astrocytes play a functional role in facilitating directional growth of regenerated axons. In an in vitro confrontation assay, GDNF treatment significantly smoothed the interface between SC and astrocyte monolayers and enhanced migration of astrocytes onto the SC monolayer, confirming the in vivo experiments. However, GDNF did not promote migration of astrocytes in the absence of SCs in a scratch wound healing assay suggesting that GDNF-mediated migration of astrocytes into a SC-graft environment may result from a decrease of adhesion between astrocytes and SCs. Lastly, reduced astrocytic hypertrophy, glial fibrillary acidic protein (GFAP) and chondroitin sulfate proteoglycan (CSPG) expressions were found in vitro coculture system as well as in vivo at the graft-host interface confirming the reduction of astrogliosis after GDNF treatment. Together, our study demonstrates a novel role of GDNF on modification of astrogliosis at the graft-host interfaces and indicates that properties of host astrocytes can be modified from inhibitory to permissive to create a favourable environment for robust axonal regeneration.

    • Funded by:
    • NIH grants NS36350
    • NIH grants NS52290
    • NIH grants NS50243
    • NIH grants NS09923


    Co-transplantation of adult neural progenitor cells with cells of mesenchymal origin for oligodendrogia replacement after spinal cord injury (Beatrice Sandner)
    The loss of oligodendroglia and the resulting demyelination represents one of the key problems inhibiting recovery from spinal cord injury. The transplantation of adult neural progenitor cells (NPC) might be a promising oligodendroglia replacement strategy. After transplantation into the acutely injured spinal cord, NPC readily survive, however, only a relatively minor proportion of grafted NPC differentiates into oligodendroglia. In vitro, oligodendroglial differentiation can be strongly enhanced by co-cultivating mesenchymal stem cells (MSC) with NPC. The aim of the present study was to investigate whether co-transplantation of NPC with MSC into the injured spinal cord will significantly enhance oligodendroglial differentiation of NPC in vivo. For both syngenic cell isolation and the in vivo experiments adult female Fischer 344 rats were taken. NPC were isolated from the subventricular zone, MSC from the femur and fibroblasts (FF) from skin biopsies. Before transplantation, NPC were prelabeled with BrdU. Rats received cervical tungsten wire knife dorsal column transections. Immediately thereafter, a) 0.6 x 105 MSC/µl (MSC), b) 1.8 x 105 NPC/µl (NPC), c) 0.3 x 105 MSC/µl + 1.2 x 105 NPC/µl (MSC/NPC) or 0.3 x 105 FF/µl + 1.2 x 105 NPC/µl (FF/NPC) were transplanted directly into the lesion site. Six weeks post-operatively, only FF or MSC containing grafts replaced the cystic lesion defect. Vast detection of BrdU positive nuclei indicated robust survival of NPC within respective grafts. Surprisingly, the quantification of immunohistochemical markers for oligodendroglia, namely APC and GST-pi showed a shift of NPC differentiation towards an oligodendroglial phenotype in FF/NPC grafts, but not in MSC/NPC grafts. Furthermore, it seems that the endogenous gliogenesis is also shifted towards an oligodendroglial phenotype, which has to be confirmed by thorough quantitative analysis. Ongoing studies investigate whether the promotion of oligodendroglial differentiation enhances remyelination within and outside of FF/NPC co-grafts. At this point, the combination of NPC with fibroblasts rather than MSC induces oligodendroglial differentiation in vivo as a potential strategy for oligodendroglial replacement and remyelination after spinal cord injury.

    • Funded by:
    • Bavarian State Ministry of Sciences, Research and the Arts, “ForNeuroCell” grant


    Promotion of axonal regeneration by over-expressing a NGF-soluble Nogo receptor fusion protein (Xuenong Bo)
    Nogo receptor (NgR) mediates the inhibitory effects of the three known myelin-associated proteins (MAPs), Nogo, myelin associated glycoprotein, and oligodendrocyte myelin glycoprotein, on axon regeneration in the central nervous system. A truncated soluble form of NgR (sNgR) has been reported to block the effects of MAPs and promote axon regeneration. In this study, we fused the sNgR to nerve growth factor (NGF) and used NGF to target sNgR to the intercellular space in order to neutralize MAPs. NGF in NGF-sNgR fusion protein was still biologically active as it could induce the differentiation of PC12 cells in vitro and the sprouting of calcitonin gene related peptide containing axons when delivered to spinal cord using lentiviral vector (LV). In vitro study showed that secreted NGF-sNgR was able to reduce the inhibition of MAPs on neurite outgrowth of dissociated sensory neurons. In a dorsal column injury model, sensory axons were shown to grow into the lesion cavity in animals injected with LV/NGF-sNgR near the lesion sites, while in groups injected with LV/GFP or LV/NGF-GFP regenerating sensory axons terminated before they reached the lesion cavity. In combination with a peripheral nerve conditioning lesion, some sensory axons were able to grow across the lesion cavity and into the spinal cord rostral to the lesion in the LV/NGF-sNgR injected animals. The results indicate that NGF-sNgR fusion protein can reduce the inhibition of MAPs and promote sensory axon regeneration.
    Supported by The Royal Society, UK and Stryker Corporation.

    • Funded by:
    • The Royal Society
    • Stryker corporation


    A combination therapy to repair the injured spinal cord (Masanori Sasaki)
    Spinal cord injury (SCI) results in motor and sensory dysfunction below the level of injury, in part because of a disruption of descending motor signals transmitted from the brain to the spinal cord. We and others have previously demonstrated that pyramidal neurons in the primary motor cortex (M1) are lost after SCI. Therefore rescuing injured cortical neurons represents an important therapeutic approach in the treatment of paralysis after SCI. Orally administered phenytoin (PHT) can promote spinal cord motor axon sparing in various injury models, and transplantation of olfactory ensheathing cell (OEC) can reduce loss of M1 neurons after axotomizing SCI (Sasaki et al., 2006). In the present study, we examined the ability of a combination therapy with OEC transplant and PHT treatment to further improve motor function in rats with SCI. In three experimental groups (SCI+PHT chow+OEC, SCI+PHT chow+DMEM, SCI+normal chow+DMEM), the individual and synergistic effects of OEC transplants and PHT treatment were assessed. A dorsal transection lesion at T9 was produced in the spinal cord of rats given PHT chow with an ophthalmic scalpel. Immediately after the transection, OECs (1.5 x 105 cells) or DMEM were transplanted via a glass micropipette. Fluorogold (FG) was injected into the epicenter of the lesion cavity to identify injured corticospinal tract (CST) neurons. The animals were perfused at 1 and 4 weeks after the transplantation. Stereologic quantification was performed on the brains of transplanted rats at 1 and 4 weeks after SCI to determine neuronal density in M1. Quantitative analysis of FG+ backfilled cells demonstrated an increase number of surviving CST neurons in the M1 cortex following SCI for both the SCI+PHT chow+OEC group and the SCI+PHT chow+DMEM group. The SCI+PHT chow+OEC group, however, demonstrated a stronger effect suggesting the benefit of combining treatments. Motor evoked potential (MEP) recordings demonstrated increased response latency in stimulus-evoked motor activity for all SCI animals. Stimulus threshold for eliciting motor activity was decreased for PHT and OEC treated animals, compared to untreated SCI animals. Basso, Beattie, and Bresnahan (BBB) locomotor rating scale and Rotorod testing showed that locomotor recovery was greater for both SCI+PHT chow+OEC group and SCI+PHT chow+DMEM group. Our data suggests that the combination of OEC transplants and PHT treatment can contribute to functional recovery after SCI.

    • Funded by:
    • NIH Grant NS043432
    • Department of Veterans Affairs
    • National Multiple Sclerosis Society: RG2135; CA1009A10
    • Mike Utley Foundation
    • PVA Research Foundation #2469


    Glial-derived neurotrophic factor-expressing mesenchymal stem cells survive transplantation ino the contused spinal cord without differentiating into neural cells (Gemma E Rooney)
    The aim of this study was to assess the feasibility of transplanting mesenchymal stem cells (MSCs), genetically modified to express glial-derived neurotrophic factor (GDNF), to the contused rat spinal cord and to subsequently assess their neural differentiation potential.
    MSCs expressing green fluorescent protein (GFP) were transduced with a retroviral vector to express the neurotrophin GDNF. The transduction protocol was optimized by using GFP-expressing retroviral constructs; approximately 90% of MSCs were transduced successfully after G418 selection. GDNF-transduced MSCs secreted growth factor into the media (~12 ng/mL secreted into the supernatant 2 weeks after transduction). Injuries were established using an impactor device which applied a specific and reproducible force to the exposed spinal cord. GDNF-expressing MSCs were transplanted rostral and caudal to the site of injury. Spinal cord sections were analyzed 2 and 6 weeks after transplantation.
    GDNF-transduced MSCs were shown to engraft, survive and express the therapeutic gene up to 6 weeks post-transplantation, while maintaining an undifferentiated phenotype. In conclusion, transplanted MSCs have limited capacity for the replacement of neural cells lost as a result of spinal cord trauma. However they provide excellent opportunities for local delivery of neurotrophic factors into the injured tissue. This study underlines the therapeutic benefits associated with cell transplantation and provides a good example of the use of MSCs for gene delivery.

    • Funded by:
    • Science Foundation Ireland Centres for Science, Engineering and Technology award
    • A.J.W. was supported by the Walton fellowship from Science Foundation Ireland
    • G.E.R. was supported by the Irish Research Council for Science and Engineering Technology.


    Treatment with Glivec enhances function in experimental spinal cord injury (Mathew B Abrams)
    Traumatic injury to the spinal cord results in sensorimotor functional impairment below the level of the injury for which there is currently no cure. The initial mechanical insult triggers a secondary wave of damage that progressively exacerbates functional impairment. This phase has been attributed to many factors, among them the inflammatory response. Experimental approaches aimed at inhibiting/attenuating the inflammatory response have yielded moderate improvements in sensorimotor function. Experimentally, it is reported that Glivec, a specific tyrosine kinase inhibitor, attenuate the activation of inflammatory cells thought to contribute to exacerbate functional impairment in spinal cord injury. Therefore, the objective of this research was to determine whether treatment with Glivec improves locomotor function in an experimental model of severe spinal cord injury. We found that treatment with Glivec significantly enhanced hindlimb locomotor function. Interestingly, the functional enhancement was also associated with a significant reduction in injury-induced weight loss and a significant reduction in urinary retention volume. These results suggest the therapeutic potential of immunomodulatory therapies in spinal cord injury.

    • Funded by:
    • AFA
    • Swedish Research Council
    • Swedish Brain Foundation
    • Karolinska Institute
    ...it's worse than we thought. it turns out the people at the white house are not secret muslims, they're nerds.

  10. #30
    While I'm at it, some non-SfN news:

    Repair of thoracic spinal cord injury by chitosan tube implantation in adult rats.
    Li X, Yang Z, Zhang A, Wang T, Chen W.


    Beijing Institute for Neuroscience, Capital Medical University, Beijing 100069, China; Department of Bioengineering, Beijing University of Aeronautics and Astronautics, Beijing 100083, China.

    Spinal cord injury (SCI) is a common outcome of traffic accidents and trauma with severe consequences. There has been no cure for such a condition. We performed experiments to evaluate the feasibility of implanting a chitosan tube filled with semifluid type I collagen into the site of surgically induced SCI to facilitate functional recovery. After a segment of the spinal cord, 4mm in length and 2/3 of the spinal cord across its width, at the ninth thoracic level of an adult rat was dissected and removed, the biodegradable chitosan tube was implanted into the lesioned site. One year later, we found that axons from the proximal spinal cord regenerated, traversed the dissected area inside the tube and reentered the distal spinal cord, leading to functional restoration of the essentially paralyzed hind limbs. The nerve regeneration and functional recovery were confirmed by immunohistochemistry, electron microscopy, nerve tracing and Basso-Beattie-Bresnahan behavioral evaluation. Such beneficial outcomes were not observed in the control groups, in which either no tube was implanted or the implanted tube had no collagen filling. We conclude that the newly designed tube implant promotes both axon regeneration and functional recovery following SCI. A similar approach may have clinical implications in humans.
    ...it's worse than we thought. it turns out the people at the white house are not secret muslims, they're nerds.

Similar Threads

  1. 2008 DAM2DAM Thumbs Up! Bike Tour
    By manouli in forum Cure
    Replies: 1
    Last Post: 09-06-2008, 08:51 PM
  2. The 3rd International Rare Neuroimmunologic Disorders Symposium
    By jlubin in forum Tranverse Myelitis, Multiple Sclerosis, Non-traumatic SCI
    Replies: 5
    Last Post: 08-23-2008, 11:37 PM
  3. Replies: 0
    Last Post: 11-22-2001, 09:31 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •