• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2018.10a
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• pp.448-451
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• 2018

The purpose of this study was to investigate the developmental process of myelination by neuron and Schwann cell cultures and the development of demyelination by herpes simplex virus-1 infection by electron microscopy and molecular biological analysis. The dorsal root ganglion (DRG) was isolated from the mouse embryo and Schwann cells and neuronal cells were cultured in vitro. Neuronal cells treated with mitotic inhibitors and purified Schwann cells were co-cultured together to induce myelination. The herpes simplex virus-1 was infected with the co-cultured cells, and the demyelination was induced. The myelin protein zero (MPZ) antibody, which means the presence of myelin formation, was used and electron microscopy was used to observe the development of myelin and dehydration.

• Journal of Ginseng Research
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• v.47 no.2
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• pp.319-328
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• 2023

Background: Demyelination has been observed in neurological disorders, motivating researchers to search for components for enhancing remyelination. Previously we found that Rb1, a major ginsenoside in Korean Red Ginseng (KRG), enhances myelin formation. However, it has not been studied whether Rb1 or KRG function in remyelination after demyelination in vivo. Methods: Mice were fed 0.2% cuprizone-containing chow for 5 weeks and returned to normal chow with daily oral injection of vehicle, KRG, or Rb1 for 3 weeks. Brain sections were stained with luxol fast blue (LFB) staining or immunohistochemistry. Primary oligodendrocyte or astrocyte cultures were subject to normal or stress condition with KRG or Rb1 treatment to measure gene expressions of myelin, endoplasmic reticulum (ER) stress, antioxidants and leukemia inhibitory factor (LIF). Results: Compared to the vehicle, KRG or Rb1 increased myelin levels at week 6.5 but not 8, when measured by the LFB⁺ or GST-pi⁺ area within the corpus callosum. The levels of oligodendrocyte precursor cells, astrocytes, and microglia were high at week 5, and reduced afterwards but not changed by KRG or Rb1. In primary oligodendrocyte cultures, KRG or Rb1 increased expression of myelin genes, ER stress markers, and antioxidants. Interestingly, under cuprizone treatment, elevated ER stress markers were counteracted by KRG or Rb1. Under rotenone treatment, reduced myelin gene expressions were recovered by Rb1. In primary astrocyte cultures, KRG or Rb1 decreased LIF expression. Conclusion: KRG and Rb1 may improve myelin regeneration during the remyelination phase in vivo, potentially by directly promoting myelin gene expression.

• Journal of The Korean Dental Society of Anesthesiology
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• v.11 no.1
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• pp.45-50
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• 2011

Bell's palsy is an isolated facial paralysis of sudden onset caused by a neuritis of the seventh nerve within the facial canal. It occurs often in the adult man with a history of recent exposure to local cold, such as sleeping next to an open window, or in some cases it occurs after infections of the nasopharynx or masticator spaces. Especially, this neuropathy have linked with the major collagen disorders (diabetes mellitus). A segmental demyelination develops rapidly, with vascultitis in microinfarcts and ischemia to the nerve segment. The authors experienced about the bizarre neurological symptom of Bell's palsy after inferior alveolar nerve block anesthesia and TMJ dislocation in diabetic mellitus. The early and correct consultation with the multiple medical and dental departments was important to prevent the inadequate care & medicolegal problems.

• Korean Journal of Veterinary Research
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• v.41 no.4
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• pp.591-596
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• 2001

The chicks from 6 field broiler farms revealed peripheral neuropathy including leg weakness, curled toes and drooped wings. Grossly distinctive enlargements of sciatic nerve, branchial nerve and lumbar nerve were observed in the chicks. Histologically nerve lesions consisted of demyelination of myelin sheaths, Schwann cell proliferation and swelling, and interstitial edema in the peripheral nerves of all birds examined. Axonal swelling and infiltration of small lymphocytes were observed, but not a primary lesion. After treatment of riboflavin, neurological disorder was markedly recovered. From these results, it is suggested that the peripheral nerve lesions in these cases were caused by dietary riboflavin deficiency.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.36 no.5
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• pp.360-365
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• 2010

Introduction: Mammalian tooth pulp is densely innervated by sensory nerves that are mostly C fibers and A delta fibers. However, there is evidence suggesting that many unmyelinated axons in the pulp are in fact parent meylinated axons. Immunohistochemical staining for neurofilament protein 200 kDa (NFP200) was performed to identify the demyelinated but parent myelinated axons. Materials and Methods: The pulp was removed from healthy premolars and 3rd molars extracted from juveniles and adults undergoing orthodontic treatment, and immunohistochemical staining were applied with NPF200 antibodies, which specifically dye myelinated axons. The specimens underwent an electron microscopy examination with diaminobenzidine (DAB) immunostaining after observation and analysis by fluorescence and confocal laser scanning microscopy. Results: The NPF200 immuno-positive axons in the radicular pulp areas were observed as bundles of many nerve fibers. Many small bundles were formed with fewer axons when firing to the coronal pulp areas and then reachrd a different direction. In the radicular pulp, unmyelinated axons and myelinated axons were present together. However, in the coronal pulp, unmyelinated axons were most common and NFP200 immuno-positive unmyelinated axons with a larger diameter than those in the radicular pulp were observed more frequently. On the other hand, most of the immuno-positive unmyelinated fibers were similar in size to that of typically well-known unmyelinated fibers. Conclusion: Myelinated fibers innervated to the dental pulp maintain their myelins in the radicular portion, but these fibers lost myelins in the coronal portion. After the loss of myelin, the size of the axoplasm also decreased.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.14 no.1
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• pp.54-59
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• 2014

Adrenoleukodystrophy is an X-linked genetic disease resulting from mutations in the ABCD1 gene. Cerebral adrenoleukodystrophy is one of the phenotypes of adrenoleukodystrophy and shows progressive demyelination of brain white matter and adrenal insufficiency. We report a nine year old male who presented with rapidly progressive cognitive and neurologic deterioration. He had abnormal findings in brain imaging and elevated very long chain fatty acid level in serum. Mutation analysis of ABCD1 revealed a c. 1252C>T (p.Arg418Trp) mutation which was previously known but not reported in Korea.

• Molecules and Cells
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• v.38 no.11
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• pp.1013-1021
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• 2015

Most of the axons in the vertebrate nervous system are surrounded by a lipid-rich membrane called myelin, which promotes rapid conduction of nerve impulses and protects the axon from being damaged. Multiple sclerosis (MS) is a chronic demyelinating disease of the CNS characterized by infiltration of immune cells and progressive damage to myelin and axons. One potential way to treat MS is to enhance the endogenous remyelination process, but at present there are no available treatments to promote remyelination in patients with demyelinating diseases. Sulfasalazine is an anti-inflammatory and immune-modulating drug that is used in rheumatology and inflammatory bowel disease. Its anti-inflammatory and immunomodulatory properties prompted us to test the ability of sulfasalazine to promote remyelination. In this study, we found that sulfasalazine promotes remyelination in the CNS of a transgenic zebrafish model of NTR/MTZ-induced demyelination. We also found that sulfasalazine treatment reduced the number of macrophages/microglia in the CNS of demyelinated zebrafish larvae, suggesting that the acceleration of remyelination is mediated by the immunomodulatory function of sulfasalazine. Our data suggest that temporal modulation of the immune response by sulfasalazine can be used to overcome MS by enhancing myelin repair and remyelination in the CNS.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2019.05a
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• pp.528-532
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• 2019

The dorsal root ganglion (DRG) was isolated from mouse embryos and Schwann cells and neuronal cells were cultured in vitro. The neurons and Schwann cells were cultured separately and the two kinds of cells were cultured together for three weeks. Generation of myelination was confirmed by transmission electron microscope and confocal microscope using a myelinaion protein, myelin protein zero (MPZ) antibody. The sindbis virus was infected for three days in the myelinated culture cells and then demyelination was carried out. The process of demyelination was also confirmed by transmission electron microscopy and confocal microscopy using myelin protein zero (MPZ) antibody. The study was supported by a Basic Research Program through the National Research Foundation (NRF) funded by the Ministry of Science and Technology, ICT and Future Plans (NRF-2016R1A2B4016552 and 2017R1A2B3005753).

• Annals of Clinical Neurophysiology
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• v.25 no.2
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• pp.84-92
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• 2023

Background: Clinical spectrum of immunoglobulin M (IgM) monoclonal gammopathy varies from IgM monoclonal gammopathy of unknown significance (IgM-MGUS) to hematological malignancies. We evaluated the clinical features, electrophysiological characteristics, and prognosis of patients with peripheral neuropathy associated with IgM monoclonal gammopathy (PN-IgM MG). Methods: We retrospectively evaluated 25 patients with PN-IgM MG. Peripheral neuropathy was classified as axonal, demyelinating, or undetermined, based on electrophysiological studies. We classified the enrolled patients into the IgM-MGUS and malignancy groups, and compared the clinical and electrophysiological features between the groups. Results: Fifteen patients had IgM-MGUS and 10 had hematologic malignancies (Waldenström's macroglobulinemia: two and B-cell non-Hodgkin's lymphoma: eight). In the electrophysiological evaluation, the nerve conduction study (NCS) criteria for demyelination were met in 86.7% of the IgM-MGUS group and 10.0% of the malignancy group. In particular, the distal latencies of the motor NCS in the IgM-MGUS group were significantly prolonged compared to those in the malignancy group (median, 9.1 ± 5.1 [IgM-MGUS], 4.2 ± 1.3 [malignancy], p = 0.003; ulnar, 5.4 ± 1.9 [IgM-MGUS], 2.9 ± 0.9 [malignancy], p = 0.001; fibular, 9.3 ± 5.1 [IgM-MGUS], 3.8 ± 0.3 [malignancy], p = 0.01; P-posterior tibial, 8.3 ± 5.4 [IgM-MGUS], 4.4 ± 1.0 [malignancy], p = 0.04). Overall treatment responses were significantly worse in the malignancy group than in the IgM-MGUS group (p = 0.004), and the modified Rankin Scale score at the last visit was higher in the malignancy group than in the IgM-MGUS group (2.0 ± 1.1 [IgM-MGUS], 4.2 ± 1.7 [malignancy], p = 0.001), although there was no significant difference at the initial assessment. Conclusions: The risk of hematological malignancy should be carefully assessed in patients with PN-IgM MG without electrophysiological demyelination features.

• Korean Journal of Biological Psychiatry
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• v.2 no.2
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• pp.301-305
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• 1995

Subcortical dementia may occur as a complication of cerebral malaria via deep white matter demyelination with encephalitis and diffuse small vessel vasculitis. In subcortical dementia, impairment in attention and frontal executive function are predominant. Patients are often inert, indifferent, and uninterested. They appear characteristically 'slowed up' with a marked deficit in the retrieval of information. Changes in mood, personality, and social conduct are very common. We describe a case of subcortical dementia, who has definite changes in brain MRI after cerebral malaria.