• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.6
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• pp.1640-1646
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• 2005

An oriental medicinal drugs Jahageo (JHG, Hominis placenta) were examined to determine its effects on the responsiveness of central nervous system neurons after injury. We found that JHG was involved in neurite outgrowth of DRG sensory axons. JHG treatment also increased expression of axonal growth-associated protein GAP-43 in DRG sensory neurons after sciatic nerve injury and in the injured spinal cord. JHG treatment during the spinal cord injury increased induction levels of cell division cycle 2 (Cdc2) protein in DRG as well as in the spinal cord. Histochemical investigation showed that induced Cdc2 in the injured spinal cord was found in non-neuronal cells. These results suggest that JHG regulates activities of non-neuronal cells such as oligodendrocyte and astrocyte in responses to spinal cord injury and protects neuronal responsiveness after axonal damage.

• Molecules and Cells
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• v.37 no.8
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• pp.613-619
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• 2014

The optic nerve often suffers regenerative failure after injury, leading to serious visual impairment such as glaucoma. The main inhibitory factors, including Nogo-A, oligodendrocyte myelin glycoprotein, and myelin-associated glycoprotein, exert their inhibitory effects on axonal growth through the same receptor, the Nogo-66 receptor (NgR). Oncomodulin (OM), a calcium-binding protein with a molecular weight of an ~12 kDa, which is secreted from activated macrophages, has been demonstrated to have high and specific affinity for retinal ganglion cells (RGC) and promote greater axonal regeneration than other known polypeptide growth factors. Protamine has been reported to effectively deliver small interference RNA (siRNA) into cells. Accordingly, a fusion protein of OM and truncated protamine (tp) may be used as a vehicle for the delivery of NgR siRNA into RGC for gene therapy. To test this hypothesis, we constructed OM and tp fusion protein (OM/tp) expression vectors. Using the indirect immunofluorescence labeling method, OM/tp fusion proteins were found to have a high affinity for RGC. The gel shift assay showed that the OM/tp fusion proteins retained the capacity to bind to DNA. Using OM/tp fusion proteins as a delivery tool, the siRNA of NgR was effectively transfected into cells and significantly down-regulated NgR expression levels. More importantly, OM/tp-NgR siRNA dramatically promoted axonal growth of RGC compared with the application of OM/tp recombinant protein or NgR siRNA alone in vitro. In addition, OM/tp-NgR siRNA highly elevated intracellular cyclic adenosine monophosphate (cAMP) levels and inhibited activation of the Ras homolog gene family, member A (RhoA). Taken together, our data demonstrated that the recombinant OM/tp fusion proteins retained the functions of both OM and tp, and that OM/tp-NgR siRNA might potentially be used for the treatment of optic nerve injury.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.5
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• pp.1303-1310
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• 2006

In oriental medicine, Samul-tang (SMT) has been used for the treatment of cardiovascular diseases and neuronal disorders. Here, possible effects of SMT on axonal regeneration after the spinal cord injury were examined. SMT treatment induced increases in regeneration-related proteins GAP-43, cell division cycle 2 (Cdc2) and phospho-Erk1/2 in the peripheral sciatic nerves after crush injury. Increased levels of Cdc2 and phospho-Erk1/2 were observe mostly in the gray matter area and some in the dorsomedial white matter. These increases correlated with increased cell numbers in affected areas. Moreover, axons of corticospinal tract (CST) showed increased sprouting in the injured spinal cord when administrated with SMT compared with saline-treated control. Thus, the present data indicate that SMT may be useful for identifying active components and for therapeutic application toward the treatment of spinal cord disorders after injury.

• Journal of Korean Medicine Rehabilitation
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• v.18 no.4
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• pp.39-61
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• 2008

Objectives : The present study was performed to investigate whether acupuncture stimulation in the rats affected regeneration properties of the injured sciatic nerve. A differential effect of acupuncture stimulation on the one point near the spinal nerve root controlling sciatic nerve activity and the other point in the peripheral area subordinated by injured nerve was compared. Materials and Methods: Rat sciatic nerves were injured by crush, and the effects on axonal regeneration on injured sciatic nerves were evaluated by acupuncture stimulation at two different regions. In proximal acupuncture stimulation group, acupuncture stimulation was performed on Huatuo Jiaji(EX B2) points located from L5 to S1 vertebral levels to stimulate the nearest spinal nerve root that innervates sciatic nerves. In distal acupuncture stimulation group, acupuncture stimulation was performed on Zusanli(ST 36) and Weizhong(BL 40) points to stimulate at peripheral area dominated by injured sciatic nerves. Acupuncture stimulation was given every other days for 1 or 2 weeks. Sciatic nerve tissues collected from acupuncture stimulation experimental groups, injury control group, and intact animal group were used for protein analysis by Western blotting or Hoechst nuclear staining. To determine axonal regeneration, Dil fluorescence dye was injected into the sciatic nerve 0.5 cm distal to the injury site in individual animal groups and Dil-labeled cells by retrograde tracing were measured in the DRG at lumbar 5 or in the spinal cord. DRG sensory neurons prepared from individual animal groups were used to measure the extent of neurite outgrowth and for immunofluorescence staining with anti-GAP-43 antibody. Results : Animal groups given proximal or distal acupuncture stimulation showed upregulation of GAP-43 and Cdc2 protein levels in the sciatic nerve at 7 days after injury. Cdk2 protein levels were strongly induced by nerve injury, but did not show changes by acupuncture stimulation. Phospho-Erk1/2 protein levels were elevated by acupuncture stimulation above those present in the injury control animals. These increase in regeneration-associated protein levels appeared to be related with increase cell proliferation in the injured sciatic nerves. Hoechst 33258 staining of sciatic nerve tissue to visualize nuclei of individual cells showed increased Schwann cell number in the distal portion of the injured nerve 7 and 14 days after injury and further increases by acupuncture stimulation particularly at the proximal position. Measurement of axonal regeneration by retrograde tracing showed significantly increased Dil-labeled cells in proximal acupuncture stimulation group compared to distal acupuncture stimulation group and injury control group. Finally, an evaluation of axonal regeneration by retrograde tracing showed increased number of Dil labeled cells in the DRG at lumbar 5 or in the ventral horn of the spinal cord at lower thoracic level at 7 days after nerve injury. Conclusions : The present data show that the proximal acupuncture stimulation at Huatuo Jiaji(EX B2) points governing injured sciatic nerves was more effective for axonal regeneration than the distal acupuncture stimulation. Further studies on functional recovery or associated molecular mechanisms should be critical for developing animal models and clinical applications.

• Journal of Life Science
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• v.16 no.3 s.76
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• pp.464-471
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• 2006

Peripheral nerve injuries are a commonly encountered clinical problem and often result in severe functional deficits. In the present study, the effects of treadmill exercise on neurotrophin expressions and functional recovery following sciatic crushed nerve injury were investigated. Animals were randomly assigned into four groups: the sciatic nerve injury group, the sciatic nerve injury and 3-day-exercise, the sciatic nerve injury and 7-days-exercise, and the sciatic nerve injury and 14-days-exercise groups. Sciatic nerve injury was caused by crushing the right sciatic nerve for 30 s using a surgical clip. A the light-exercise was applied to each of the exercise group over the respective number of days. In the present results, we identified enhanced axonal re-growth in the distal stump of the sciatic nerve 3-14 days after crush injury with treadmill training. Dorsal root ganglion (DRG) neuron when cultured from animals with nerve injury and treadmill training showed more enhanced neurite outgrowth than that of sedentary animals. Nerve growth factor (NGF) protein levels in low-intensity treadmill training group were highly induced in the injured sciatic nerves 3, 7 and 14 days after injury compared with sedentary group, and brain-derived neurotrophin factor (BDNF) protein levels in treadmill exercise group were highly induced in the injured sciatic nerve 3 days after injury compared with sedentary group. Then, treadmill exercise increased neurotrophic factors induced in the regenerating nerves. We further demonstrate that motor functional recovery after sciatic nerve injury was promoted by treadmill exercise. Thus, the present data provide a new evidence that treadmill exercise enhanced neurotrophins expression and axonal regeneration after sciatic nerve injury in rats.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.1
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• pp.145-152
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• 2007

Following CNS injury, inhibitory influences at the site of axonal damage occur. Glial cells become reactive and form a glial scar, gliosis. Astrocyte-rich gliosis relates with up-regulation of GFAP and CD81, and eventually becomes physical and mechanical barrier to axonal regeneration. It is postulated that the astrocytic reaction is absent, regeneration of axons can occur. And it was reported that treatment with anti CD81 antibodies enhanced functional recovery in the rat with spinal cord injury. So in this current study, the author investigated the effect of the water extract of Persicae Semen on the regulation of GFAP and CD81 that increase when gliosis occurs. Persicae Semen decreased the expression of GFAP and CD81 in astrocyte cell by ELISA method. Persicae Semen decreased the RNA expression of CD81 and GFAP. The proteins that separate in whole cell were analaysed by western blot, and the expression of GFAP and CD81 was decreased. In vivo, rats brains were peformed cortical stab wound, the water extracts of Persicae Semen were injected for 7 days, 30 days. As a result, GFAP and CD81 expression were decreased in immunohistochemistry. These findings demonstrate that Persicae Semen decreases GFAP and CD81 expression. Accordingly, Persicae Semen could be a candidate for promotion of axon regeneration after CNS injury.

• The Korean Journal of Pain
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• v.29 no.1
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• pp.3-11
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• 2016

A nerve block is an effective tool for diagnostic and therapeutic methods. If a diagnostic nerve block is successful for pain relief and the subsequent therapeutic nerve block is effective for only a limited duration, the next step that should be considered is a nerve ablation or modulation. The nerve ablation causes iatrogenic neural degeneration aiming only for sensory or sympathetic denervation without motor deficits. Nerve ablation produces the interruption of axonal continuity, degeneration of nerve fibers distal to the lesion (Wallerian degeneration), and the eventual death of axotomized neurons. The nerve ablation methods currently available for resection/removal of innervation are performed by either chemical or thermal ablation. Meanwhile, the nerve modulation method for interruption of innervation is performed using an electromagnetic field of pulsed radiofrequency. According to Sunderland's classification, it is first and foremost suggested that current neural ablations produce third degree peripheral nerve injury (PNI) to the myelin, axon, and endoneurium without any disruption of the fascicular arrangement, perineurium, and epineurium. The merit of Sunderland's third degree PNI is to produce a reversible injury. However, its shortcoming is the recurrence of pain and the necessity of repeated ablative procedures. The molecular mechanisms related to axonal regeneration after injury include cross-talk between axons and glial cells, neurotrophic factors, extracellular matrix molecules, and their receptors. It is essential to establish a safe, long-standing denervation method without any complications in future practices based on the mechanisms of nerve degeneration as well as following regeneration.

• The Journal of Korean Physical Therapy
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• v.12 no.3
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• pp.395-406
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• 2000

In general. it is known that central nervous system associated with nerve injury and regeneration in mature cann't regenerate, unlikely peripheral nervous system, due to various reasons. Although a lot of Patients arc suffered with central nervous system injury in the world, but there art a few resolution and researches and investigations. 'rho effect of central nervous system regeneration was partly revealed by many researchers. In this article, we describe about recovery (inclusive of axonal regeneration, remyelination, repair of spinal cord) and associated factors(inclusive of macrophage and autoimmune T-cell. neural stem cells. Nogo) after central nervous system injury.

• Journal of Haehwa Medicine
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• v.14 no.1
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• pp.201-211
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• 2005

Cdc2 kinase is a prototypical cyclin-dependent kinase critical for G2 to M phase cell cycle transition. Yet, its function in the nervous system is largely unknown. Here, we investigated possible role of Cdc2 in axonal regeneration using sciatic nerve system in rat. Cdc2 protein levels and activity were increased in the injured sciatic nerves 3 and 7 days after crush injury and then decreased to basal level 14 days later. Administration of Cdc2 kinase inhibitor roscovitine in vivo at the time of crush injury significantly inhibited axonal regeneration when regrowing axons were analyzed using retrograde tracers. Cdc2 protein levels in cultured Schwann cells which were prepared from sciatic nerves 7 days after crush injury were much higher compared with those from uninjured sciatic nerves, suggesting that Cdc2 protein expression was primarily induced in the Schwann cells. To further investigate Cdc2 function in Schwann cell, we examined changes in cultured Schwann cell proliferation and migration in culture system. Both the number of proliferating Schwann cells and the extent of neurite outgrowth from co-cultured DRG neurons were significantly decreased by Cdc2 inhibitor roscovitine treatment in DRG culture which was prepared from animals with sciatic nerve injury for 7 days. Also, Schwann cell migration in the injured sciatic nerve explant was significantly inhibited by roscovitine treatment. Taken together, the present data suggest that Cdc2 may be involved in peripheral nerve regeneration via Schwann cell proliferation and migration.

• Applied Microscopy
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• v.32 no.1
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• pp.67-80
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• 2002

This study was carried out to investigate the effects of deer antler extract on the regeneration of peripheral nerves. Sprague-Dawley male rats weighing about 300 gm were fed deer antler extract for 1, 2, and 3 weeks per oral (1.5 ml/100 gm B.W.), respectively, once a day and transected both sides of sciatic nerve of each leg. After keeping for 6 hours, sciatic nerves taken from proximal part of transected region were treated with conventional transmission electron microscopical method and then observed with electron microscope. The results obtained were summarized as follows; 1. Sciatic nerves of normal control group were not showing any sprouts and electron dense axolemmal projections were frequently observed. 2. Sciatic nerves of saline treated groups were showing axonal sprouts at the nodes of Ranvier. The length of them was usually short, and numerous vesicles, vacuoles and organelles including neurofilament were contained. The number of nodes of Ranvier containing sprouts from 100 longitudinal sectioned nerve fibers was 29 (29%) in 1 week treated group, 32 (32%) in 2 weeks treated group, and 30 (30%) in 3 weeks treated group, respectively. 3. Sciatic nerves of deer antler treated groups were showing axonal sprouts at the node of Ranvier as well. Although most of the sprouts were short, some sprouts of 2 weeks and 3 weeks treated groups were quite long. Sprouts usually contained numerous vesicles, vacuoles and cell organelles such as neurofilaments and mitochondria. The number of nodes of Ranvier containing sprouts from 100 longitudinal sectioned nerve fibers was 38 (38%) in 1 week treated group, 46 (46%) in 2 weeks treated group, and 48 (48%) in 3 weeks treated group respectively. The results described above explain pretreatment of deer antler extract improves the sprout formation of transected sciatic nerves, and then it suggests deer antler may be effective for the regeneration of peripheral nerves.