• Journal of Korean Neurosurgical Society
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• v.30 no.6
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• pp.688-698
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• 2001

Objectives : Parkinson's disease is a well-known neurodegenerative disease characterized by dopaminergic cell death in the substantia nigra. The reactive gliosis by activated astrocytes and microglias is no more regarded as a simple sequel of neuronal cell death. Microglial activation takes place in a stereotypic pattern with graded morphologic and functional(resting, activated and phagocytic) changes. In Parkinson's disease animal model, the degree of microglial activation along the nigro-striatal dopaminergic tract has not been studied intensively. The purpose of this study was to elucidate the characteristics of microglial reaction and to grade its degree of activation at substantia nigra and corpus striatum using 6-hydroxydopamine induced rat model of Parkinson's disease. Methods : Using Sprague-Dawley rat, parkinsonian model was made by 6-hydroxydopamine(OHDA) induced destruction of medial and lateral substantia nigra(SN). The rat was sacrificed 3-, 5-, 7-, 14- and 21-day-after operation. For control group, we injected saline with same manner and sacrificed 3-day after operation. With immunohistochemistry, we examined dopaminergic neuronal cells and microglial expression using tyrosine hydroxylase (TH) and OX-42 antibodies, respectively. Also we performed in situ hybridization for osteopontin, a possible marker of subset in activated microglia. Results : 1) In lesioned side of substantia nigra and corpus striatum, the TH immunoreactivity was markedly decreased in whole experimental groups. 2) Using optical densitometry, microglia induced immunoreactivity of OX-42 was counted at SN and corpus striatum. At SN, it was increased significantly on the lesioned side in control and all time-dependent experimental groups. At striatum, it was increased significantly in post lesion 3-day group only(p <0.05). Compared to control group, immunoreactivity of OX-42 on lesioned side was increased in groups, except post lesion 21-day group, at SN. Only post lesion 3-day group showed significance at striatum(p <0.05). Compared to SN region, immunoreactivity of OX-42 was much weaker in striatum. 3) Microscopically, the microglias showed typically different activation pattern. At SN, numerous phagocytic microglias were found at pars compacta and reticularis of lesion side. At striatum, no phagocytic form was found and the intensity of staining was much weaker. 4) At SN, the immunoreactivity of osteopontin showed definite laterality and it was markedly increased at pars compacta of lesion side with relatively short duration time. At striatum, however, it was not detected by in situ hybridization technique. Conclusion : The nigral 6-OHDA induced rat model of Parkinson's disease revealed several characteristic patterns of microglial reaction. At SN, microglias was activated shortly after direct neuronal damage and maintained for about three weeks. In contrast, despite of sufficient dopaminergic insufficiency at striatum, activation of microglias was trivial, and distinguished 3 day later. Antegrade slow neuronal degeneration is major pathophysiology in striatal dopaminergic deficiency. So, the acuteness of neuronal damage and consequential degree of neuronal degeneration may be important factor for microglial activation in neurodegenerative diseases such as Parkinson's disease. Additionally, osteopontin may be a possible marker for several subsets of activated microglia, possibly the phagocytic form.

• 한국약용작물학회:학술대회논문집
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• 2012.05a
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• pp.179-180
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• 2012

• Journal of Life Science
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• v.28 no.11
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• pp.1332-1338
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• 2018

Activated microglia, induced by various pathogens, protect neurons and maintain homeostasis of the central nervous system (CNS). However, severe activation causes neurodegenerative disorders such as Alzheimer's disease and Parkinson's disease because of the secretion of various neurotoxic molecules, such as nitric oxide (NO), prostaglandin (PG), and pro-inflammatory cytokines. Because chronic microglial activation endangers neuronal survival, negative regulators of microglial activation have been identified as potential therapeutic candidates for treatment of many neurological diseases. One potential source of these regulators is Locusta migratoria, a grasshopper of the Acrididae, usually 4-6 cm in size, belonging to the family of large insects in Acrididae. This grasshopper is an edible insect resource that can be consumed by humans as protein source or used for animal feed. The aim of the present study was to examine the inhibitory effects of a L. migratoria ethanol extract (LME) on the production of inflammatory mediators in LPS-stimulated BV-2 microglia cells. The extract significantly inhibited the NO, iNOS, COX-2, and pro-inflammatory cytokine ($TNF-{\alpha}$, IL-6 and $IL-1{\beta}$) levels in BV-2 microglia cell. Because the inhibition of microglial activation may be an effective solution for treating brain disorders like Alzheimer's and Parkinson's diseases, these results suggest that LME may be a potential therapeutic agent for the treatment of brain disorders induced by neuroinflammation.

• Journal of Microbiology and Biotechnology
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• v.17 no.10
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• pp.1717-1720
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• 2007

In the course of screening for nitric oxide inhibitors in activated microglial BV-2 cells, cyclo(dehydrohistidyl-L-tryptophyl) was isolated from solid-state fermentation cultures of an unidentified fungal strain, Fb956. Its structure was determined by spectroscopic methods including 2D NMR and chiral TLC analyses. Cyclo(dehydrohistidyl-L-tryptophyl) was found to have an inhibitory activity on nitric oxide production with an $IC_{50}$ of $6.5\;{\mu}M$ in activated BV-2 cells. The structure determination and biological activity of cyclo(dehydrohistidyl-L-tryptophyl) was reported for the first time in this study.

• Biomolecules & Therapeutics
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• v.29 no.5
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• pp.483-491
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• 2021

Parkinson's disease (PD) is a neurodegenerative disorder that involves the loss of dopaminergic neurons in the substantia nigra (SN). Matrix metalloproteinases-8 (MMP-8), neutrophil collagenase, is a functional player in the progressive pathology of various inflammatory disorders. In this study, we administered an MMP-8 inhibitor (MMP-8i) in Leucine-rich repeat kinase 2 (LRRK2) G2019S transgenic mice, to determine the effects of MMP-8i on PD pathology. We observed a significant increase of ionized calcium-binding adapter molecule 1 (Iba1)-positive activated microglia in the striatum of LRRK2 G2019S mice compared to normal control mice, indicating enhanced neuro-inflammatory responses. The increased number of Iba1-positive activated microglia in LRRK2 G2019S PD mice was down-regulated by systemic administration of MMP-8i. Interestingly, this LRRK2 G2019S PD mice showed significantly reduced size of cell body area of tyrosine hydroxylase (TH) positive neurons in SN region and MMP-8i significantly recovered cellular atrophy shown in PD model indicating distinct neuro-protective effects of MMP-8i. Furthermore, MMP-8i administration markedly improved behavioral abnormalities of motor balancing coordination in rota-rod test in LRRK2 G2019S mice. These data suggest that MMP-8i attenuates the pathological symptoms of PD through anti-inflammatory processes.

• Korean Journal of Pharmacognosy
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• v.50 no.4
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• pp.291-298
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• 2019

Phlox subulata is a perennial herbaceous flower and is a member of the Polemoniaceae family. This plant is known to resist to various stresses including salt, drought, heat, and cold stresses. In this investigation, we evaluated the ant-inflammatory effect of the methanolic extract of P.subulata(PSM) on lipopolysaccharide(LPS)-induced RAW264.7 macrophages and BV2 microglia. PSM reduced the production of nitric oxide(NO) in LPS-stimulated both RAW264.7 and BV2 cells, but did not affect to the production of prostaglandin E2(PGE₂). It inhibited the expression of inducible nitric oxide synthase(iNOS) and cyclooxygenase(COX)-2 in both cells. In addition, PSM suppressed the production of pro-inflammatory cytokines including interleukin(IL)-6 and tumor necrosis factor(TNF)-α. These inhibitory effects were contributed by inactivation of nuclear factor kappa B(NF-κB) and mitogen-activated protein kinases(MAPKs) pathways by PSM. Thus, these results suggested that P.subulata can be a candidate material to treat inflammatory diseases.

• Herbal Formula Science
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• v.25 no.4
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• pp.537-551
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• 2017

Objectives : Jinnoe-san (JNS) is a novel herbal formula consisting of five oriental medicinal herbs including Polygalae Radix, Prunellae Spica, Perillae Herba, Betulae Cortex, and Lonicerae Flos. In this study, we investigated the effects and molecular mechanism of JNS on Parkinson's disease in vitro model. Methods : The effects of JNS on 1-methyl-4-phenylpyridinium ($MPP^+$)-induced cell death in SH-SY5Y cells were evaluated with a cell viability assay, flow cytometry, and western blots analysis. The effects of JNS on lipopolysaccharide (LPS)-stimulated BV2 microglia were determined with a nitric oxide (NO) assay, enzyme linked immunosorbent assays, and western blots analysis. Result : $MPP^+$-induced cell death in SH-SY5Y cells was significantly reduced by JNS pre-treatment in a dose-dependent manner. JNS inhibited the production of reactive oxygen species, mitochondria dysfunction, and apoptosis induced by $MPP^+$ in SH-SY5Y cells. Furthermore, JNS significantly activated Akt and ERK in SH-SY5Y cells and the ability of JNS to prevent mitochondria dysfunction by $MPP^+$ was antagonized by pre-treatment of LY294002 and PD98059, an Akt and ERK inhibitor, respectively. In addition, JNS inhibited LPS-induced NO and $PGE_2$ production as well as iNOS expression and secretion of TNF-${\alpha}$, pro-inflammatory cytokines without affecting the cell viability. JNS also suppressed LPS-induced ERK activation. Conclusions : These results demonstrate that JNS has a protective effect on the dopaminergic neurons against $MPP^+$-induced neurotoxicity and anti-inflammatory effect on the LPS-stimulated microglia. These findings provide evidences for JNS to be considered as a new prescription for treating Parkinson's disease.

• Korean Journal of Food Science and Technology
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• v.49 no.3
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• pp.331-337
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• 2017

To evaluate the antioxidant activity of hexane, ethyl acetate, and butanol fractions obtained from Agastache rugosa extract, we measured the total polyphenol levels, DPPH radical scavenging activity, and reducing power. The ethyl acetate fraction of A. rugosa (AREA) displayed high phenolic levels, potent DPPH radical scavenging effect, and powerful reducing power. In addition, we examined the ability of AREA to inhibit nitric oxide (NO) production in lipopolysaccharide (LPS)-activated BV-2 microglia. AREA suppressed NO production and inducible nitric oxide synthase (iNOS) expression and downregulated interleukin-6 (IL-6) mRNA level in LPS-stimulated BV-2 microglia. Furthermore, we detected rosmarinic acid in AREA by HPLC, which suggested that rosmarinic acid could be one of the bioactive materials responsible for the antioxidant and anti-inflammatory activities of AREA. These results suggested that AREA may be a good source of functional foods with antioxidant and anti-inflammatory activities.

• The Korea Journal of Herbology
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• v.23 no.3
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• pp.73-83
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• 2008

Objectives : The root of Zingiber officinale ROSC. (Zingiberis Rhizoma Recens; Ginger) has been widely used as one of folk remedies and food materials in many traditional preparations. Ginger is known as an effective appetite enhancer and anti-inflammatory agent. This study was performed to investigate the effect of ginger chloroform fraction (GCF) in microglia which play a central role on brain inflammation in neurodegenerative diseases. Methods : Dried ginger was extracted with 80% methanol, and then fractionated with chloroform. BV2 mouse microglial cells were cultured with different concentrations of GCF and then stimulated with LPS (1 ${\mu}g/m{\ell}$) at indicated times. The cell toxicity of GCF was determined by MTT assay. The concentrations of NO, PGE2 and cytokines were measured by Griess assay and enzyme-linked immunosorbant assay. The mRNA and protein expressions of iNOS, COX-2 and cytokines were determined by RT-PCR and Western blotting. The phosphorylation of three MAPKs (p38 MAPK, ERK1/2 and JNK) and $NF-{\kappa}B$ activation were determined by Western blotting. Results : GCF significantly inhibited LPS-induced production of inflammatory mediators, NO, $PGE_2$ and proinflammatory cytokines ($TNF-{\alpha}$ and $IL-1{\beta}$) in a dose-dependent manner. GCF attenuated LPS-induced expression of mRNA and protein of inflammatory enzymes, iNOS, COX-2 and proinflammatory cytokines through suppressing the phosphorylation of ERK1/2 and p38 MAPK and the activation of p65 $NF-{\kappa}B$ in BV2 cells. Conclusions : This study suggests that GCF may have an anti-inflammatory property through suppressing the inflammatory mediator production released by activated microglia after the brain injury.

• The Korean Journal of Physiology and Pharmacology
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• v.23 no.4
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• pp.281-289
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• 2019

Vascular endothelial growth factor (VEGF)-C and its receptor, vascular endothelial growth factor receptor (VEGFR)-3, are responsible for lymphangiogenesis in both embryos and adults. In epilepsy, the expression of VEGF-C and VEGFR-3 was significantly upregulated in the human brains affected with temporal lobe epilepsy. Moreover, pharmacologic inhibition of VEGF receptors after acute seizures could suppress the generation of spontaneous recurrent seizures, suggesting a critical role of VEGF-related signaling in epilepsy. Therefore, in the present study, the spatiotemporal expression of VEGF-C and VEGFR-3 against pilocarpine-induced status epilepticus (SE) was investigated in C57BL/6N mice using immunohistochemistry. At 1 day after SE, hippocampal astrocytes and microglia were activated. Pyramidal neuronal death was observed at 4 days after SE. In the subpyramidal zone, VEGF-C expression gradually increased and peaked at 7 days after SE, while VEGFR-3 was significantly upregulated at 4 days after SE and began to decrease at 7 days after SE. Most VEGF-C/VEGFR-3-expressing cells were pyramidal neurons, but VEGF-C was also observed in some astrocytes in sham-manipulated animals. However, at 4 days and 7 days after SE, both VEGFR-3 and VEGF-C immunoreactivities were observed mainly in astrocytes and in some microglia of the stratum radiatum and lacunosum-moleculare of the hippocampus, respectively. These data indicate that VEGF-C and VEGFR-3 can be upregulated in hippocampal astrocytes and microglia after pilocarpine-induced SE, providing basic information about VEGF-C and VEGFR-3 expression patterns following acute seizures.