• 대한한방내과학회지
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• 제35권3호
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• pp.298-308
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• 2014

Objectives: In this study we made an effort to investigate the protective effect of SSMT on the N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) -induced cytotoxicity of SH-SY5Y cells. Methods: The cell viability was assessed by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MMT) assay. The fluorescence intensity was measured by using a dye and then with propidium iodide (PI) DNA flow cytometry analysis of the effects on the cell cycle of the SH-SY5Y cells and were used to measure the fluorescence of intracellular reactive oxygen species generation by MPTP. Results: Pretreatment of SSMT significantly suppressed MPTP-induced cytotoxicity, which was revealed as apoptosis characterized by the reduction of cell viability, the increase of ROS production, and the loss of mitochondrial membrane potential in SH-SY5Y cells. Conclusions: These findings suggest that SSMT exerts neuroprotective effects on human neuroblastoma SH-SY5Y cells by MPTP-induced dopaminergic neurodegeneration.

• BMB Reports
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• 제50권2호
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• pp.60-70
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• 2017

Glaucoma is characterized by a slow and progressive degeneration of the optic nerve, including retinal ganglion cell (RGC) axons in the optic nerve head (ONH), leading to visual impairment. Despite its high prevalence, the biological basis of glaucoma pathogenesis still is not yet fully understood, and the factors contributing to its progression are currently not well characterized. Intraocular pressure (IOP) is the only modifiable risk factor, and reduction of IOP is the standard treatment for glaucoma. However, lowering IOP itself is not always effective for preserving visual function in patients with primary open-angle glaucoma. The second messenger cyclic adenosine 3',5'-monophosphate (cAMP) regulates numerous biological processes in the central nervous system including the retina and the optic nerve. Although recent studies revealed that cAMP generated by adenylyl cyclases (ACs) is important in regulating aqueous humor dynamics in ocular tissues, such as the ciliary body and trabecular meshwork, as well as cell death and growth in the retina and optic nerve, the functional role and significance of cAMP in glaucoma remain to be elucidated. In this review, we will discuss the functional role of cAMP in aqueous humor dynamics and IOP regulation, and review the current medications, which are related to the cAMP signaling pathway, for glaucoma treatment. Also, we will further focus on cAMP signaling in RGC growth and regeneration by soluble AC as well as ONH astrocytes by transmembrane ACs to understand its potential role in the pathogenesis of glaucoma neurodegeneration.

• Journal of Microbiology and Biotechnology
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• 제25권10호
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• pp.1640-1647
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• 2015

We recently reported that the antimicrobial peptide Lumbricusin (NH₂-RNRRWCIDQQA), isolated from the earthworm, increases cell proliferation in neuroblastoma SH-SY5Y cells. Here, we investigated whether Lumbricusin has neurotropic activity in mouse neural stem cells (MNSCs) and a protective effect in a mouse model of Parkinson's disease (PD). In MNSCs isolated from mouse brains, Lumbricusin treatment significantly increased cell proliferation (up to 12%) and reduced the protein expression of p27^Kip1 through proteasomal protein degradation but not transcriptional regulation. Lumbricusin inhibited the 6-OHDA-induced apoptosis of MNSCs, and also showed neuroprotective effects in a mouse PD model, ameliorating the motor impairments seen in the pole, elevated body swing, and rotation tests. These results suggest that the Lumbricusin-induced promotion of neural cell proliferation via p27^Kip1 degradation has a protective effect in an experimental PD model. Thus, the antimicrobial peptide Lumbricusin could possibly be developed as a potential therapeutic agent for the treatment of PD.

• The Korean Journal of Physiology and Pharmacology
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• 제10권4호
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• pp.167-172
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• 2006

In the present study, we developed a simple method to predict the neuronal cell death in the mouse hippocampus and striatum following transient global forebrain ischemia by evaluating both cerebral blood flow and the plasticity of the posterior communicating artery (PcomA). Male C57BL/6 mice were anesthetized with halothane and subjected to bilateral occlusion of the common carotid artery (BCCAO) for 30 min. The regional cerebral blood flow (rCBF) was measured by laser Doppler flowmetry. The plasticity of PcomA was visualized by intravascular perfusion of India ink solution. When animals had the residual cortical microperfusion less than 15% as well as the smaller PcomA whose diameter was less than one third compared with that of basilar artery, neuronal damage in the hippocampal subfields including CA1, CA2, and CA4, and in the striatum was consistently observed. Especially, when mice met these two criteria, marked neuronal damage was observed in CA2 subfield of the hippocampus. In contrast, after transient BCCAO, neuronal damage was consistently produced in the striatum, dependent more on the degree of rCBF reduction than on the plasticity of PcomA. The present study provided simple and highly reproducible criteria to induce the neuronal cell death in the vulnerable mice brain areas including the hippocampus and striatum after transient global forebrain ischemia.

• 한국한의학연구원논문집
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• 제6권1호
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• pp.89-98
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• 2000

Cerebral ischemia, the most prevalent form of clinical stroke, is a medical problem of the first magnitude. Substantial efforts are being made to develop drugs which will protect the brain from the neurodegeneration followed by an ischemic stroke. A key factor in this process is the development of animal models that mimic the neuropathological consequences of stroke. Recently, there is increasing an evidence that free radical is involved in the mechanisms of ischemic brain damage. We investigated the macro scale gene expression analysis on the global ischemia induced by 4-vessel occlusion in Wister rats. The recent availability of microarrays provides an attractive strategy for elaborating an unbiased molecular profile of large number of genes during ischemic injury. This experimental approach offers the potential to identify molecules or cellular pathways not previously associated with ischemia. Ischemia was induced by 4-vessel occlusion for 10 minutes and reperfused again. RNA from sham control brain and time-dependent ischemed brain were hybridized to microarrays containing 4,000 rat genes. 589 genes were found to be at least 2 fold regulated at one or more time points. These survey data provide the foundation studies that should provide convincing proof for ischemia and oxidative stress on gene expression.

• 한국의학물리학회지:의학물리
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• 제30권4호
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• pp.139-149
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• 2019

Purpose: With neurodegeneration, the signal intensity of the cerebrospinal fluid (CSF) in the brain increases. The objective of this study was to evaluate chemical exchange saturation transfer (CEST) signals with and without the contribution of CSF signals in elderly human brains using two different 3T magnetic resonance imaging (MRI) sequences Methods: Full CEST signals were acquired in ten subjects (Group I) with a three-dimensional (3D)-segmented gradient-echo echo-planar imaging (EPI) sequence and in ten other subjects (Group II) with a 3D gradient and spin-echo (GRASE) sequence using two different 3T MRI systems. The segmented tissue compartments of gray and white matter were used to mask the CSF signals in the full CEST images. Two sets of magnetization transfer ratio asymmetry (MTR_asym) maps were obtained for each offset frequency in each subject with and without masking the CSF signals (masked and unmasked conditions, respectively) and later compared using paired t-tests. Results: The region-of-interest (ROI)-based analyses showed that the MTR_asym values for both the 3D-segmented gradient-echo EPI and 3D GRASE sequences were altered under the masked condition compared with the unmasked condition at several ROIs and offset frequencies. Conclusions: Depending on the imaging sequence, the MTR_asym values can be overestimated for some areas of the elderly human brain when CSF signals are unmasked. Therefore, it is necessary to develop a method to minimize this overestimation in the case of elderly patients.

• Journal of Genetic Medicine
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• 제11권1호
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• pp.22-26
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• 2014

Maple syrup urine disease (MSUD) is a disorder that involves the metabolism of branched chain amino acids, arising from a defect in branched-chain ${\alpha}$-keto acid dehydrogenase complex. Mutations have been identified in the BCKDHA, BCKDHB, or DBT genes, which encode different subunits of the BCKDH complex. Although encephalopathy and progressive neurodegeneration are its major manifestations, the severity of the disease may range from the severe classic type to milder intermediate variants. We report two Korean siblings with the milder intermediate MSUD who were diagnosed with MSUD by a combination of newborn screening tests using tandem mass spectrometry and family genetic screening for MSUD. At diagnosis, the patients' plasma levels were elevated for leucine, isoleucine, valine, and alloisoleucine, and branched-chain ${\alpha}$-keto acids and branched-chain ${\alpha}$-hydroxy acids were detected in their urine. BCKDHA, BCKDHB, and DBT analysis was performed, and two novel mutations were identified in BCKDHB. Our patients were thought to have the milder intermediate variant of MSUD, rather than the classic form. Although MSUD is a typical metabolic disease with poor prognosis, better outcomes can be expected if early diagnosis and prompt management are provided, particularly for milder forms of the disease.

• 동의신경정신과학회지
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• 제23권1호
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• pp.129-143
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• 2012

Objectives : To evaluate the neuroprotective effects of the essential oil from Sohaphwangwon (SH), a Chinese traditional medicinal prescription in a Parkinson's disease mouse model. Methods : 1. The neuroprotective effect of SH on primary neuronal cells was examined by using 1-methyl-4-phenylpyridinium ion (MPP+). 2. The neuroprotective effect of SH was examined in a Parkinson's disease mouse model. C57BL/6 mice treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP, 30 mg/kg/day), intraperitoneal (i.p.) for 5 days. SH inhalation was applied before MPTP treatment for 7 days and continued until 12 days after the first MPTP treatment. 3. To find out the intracellular target signal molecule(s) regarding the neuroprotective effect of SH essential oil, brain-derived neurotropic factor (BDNF) and synaptic protein SNAP25 were examined by Western blot analysis. Results : 1. MPP+ induced a concentration-dependent decrease in cell viability. However, in the presence of 3 and 5 ug/ml of SH, MPP+-induced cell death was significantly reduced. 2. SH inhalation in MPTP mice led to the restoration of behavioral impairment and rescued tyrosine hydroxylase (TH)-positive dopaminergic neurodegeneration. 3. In SH / MPTP mice, BDNF and SNAP25 increased. Conclusions : This experiment suggests that the neuroprotective effect of SH essential oil is mediated by the expression of BDNF. Furthermore, SH essential oil may serve as a potential preventive or therapeutic agent regarding Parkinson's disease.

• Advances in Traditional Medicine
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• 제1권1호
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• pp.55-63
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• 2000

Soeumin Sibjeundaibo-tang (SJDBT) and Soyangin Sibimijihwang-tang (SMJHT) have been used traditionally to improve the systemic blood circulation and biological energy production in the patients with circulatory and neuronal diseases. The object of this study is to determine the protective effects of SJDBT and SMJHT extracts on the spontaneous and glutamate-induced neuronal damages in cultured cells derived from mice cerebral cortex. At 14 days after beginning the cultures, the activity of lactate dehydrogenase released into the culture media was significantly decreased by treatment of cerebroneuronal cells with SJDBT and SMJHT (0.1 mg/ml) for 7 days. By comparison with the normal cells, cerebroneuronal morphology was dramatically changed by treatment of glutamate (1 mM) for 12 hrs, and this was conspicuously recovered by pretreatment of cerebroneural cells with SJDBT and SMJHT (0.1-1.0 mg/ml) for 2 days. Moreover, glutamated-induced DNA fragmentation was also protected by pretreatment of cerebroneuronal cells with those extracts. These results suggest that naturally occurring and glutamate-induced degeneration of cultured cerebrocortical cells may be related, in part, to the process of apoptotic cell death. The pharmacological properties of SJDBT and SMJHT extracts to improve cerebroneuronal degeneration may be considered as one of useful medicines that can prevent cerebrocortical impairments resulted from age-dependent and excitotoxicity-induced neuronal degeneration in human brain.

• Archives of Pharmacal Research
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• 제28권9호
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• pp.1073-1078
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• 2005

A presenilin 2 mutation is believed to be involved in the development of Alzheimer's disease. In addition, transgenic mice with a presenilin 2 mutation have been reported to have learning and memory impairments. In this study, exposing PC12 cells expressing mutant presenilin 2 to $50{\mu}M\;A{\beta}_{25-35},\;30mM$ L-glutamate and $50{\mu}M\;H_2O_2$ caused a significant increase in acetylcholine esterase activity. An in vivo study revealed high levels of this enzyme activity in the mutant presenilin 2 transgenic brains compared with the wild type presenilin 2 transgenic and non-transgenic samples. These results suggest that a mutant presenilin 2-induced neurodegeneration in Alzheimer's disease might be involved in the increase in acetylcholinesterase activity. These findings might help in the development of an appropriate therapeutic intervention targeting mutant presenilin 2-induced Alzheimer's disease.