• The Korean Journal of Physiology and Pharmacology
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• 제10권4호
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• pp.173-180
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• 2006

Microglial activation is thought to play a role in the pathogenesis of many brain disorders. Therefore, understanding the response of microglia to noxious stimuli may provide insights into their role in disorders such as stroke and neurodegeneration. Many genes involved in this response have been identified individually, but not systematically. In this regards, the microarray system permitted to screen a large number of genes in biological or pathological processes. Therefore, we used microarray technology to evaluate the effect of oxygen glucose deprivation (OGD) and reperfusion on gene expression in microglia under ischemia-like and activating conditions. Primary microglial cultures were prepared from postnatal mice brain. The cells were exposed to 4 hrs of OGD and 1 h of reperfusion at $37^{\circ}C$. Isolated mRNA were run on GeneChips. After OGD and reperfusion, ＞2-fold increases of 90 genes and ＞2-fold decrease of 41 genes were found. Among the genes differentially increased by OGD and reperfusion in microglia were inflammatory and immune related genes such as prostaglandin E synthase, $IL-1{\beta}$, and $TNF-{\alpha}$. Microarray analysis of gene expression may be useful for elucidating novel molecular mediators of microglial reaction to reperfusion injury and provide insights into the molecular basis of brain disorders.

• BMB Reports
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• 제42권6호
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• pp.380-386
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• 2009

In neurodegenerative diseases, such as Alzheimer' and Parkinson', microglial cell activation is thought to contribute to CNS injury by producing neurotoxic compounds. Prothrombin and kringle-2 increase levels of NO and the mRNA expression of iNOS, IL-1$\beta$, and TNF-$\alpha$ in microglial cells. In contrast, the human prothrombin kringle-2 derived peptide NSA9 inhibits NO release and the production of pro-inflammatory cytokines such as IL-1$\beta$, TNF-$\alpha$, and IL-6 in LPS-activated EOC2 microglia. In this study, we investigated the anti-inflammatory effects of NSA9 in human prothrombin- and kringle-2-stimulated EOC2 microglia. Treatment with 20-100 ${\mu}M$ of NSA9 attenuated both prothrombin- and kringle-2-induced microglial activation. NO production induced by MAPKs and NF-$\kappa$B was similarly reduced by inhibitors of ERK (PD98059), p38 (SB203580), NF-$\kappa$B (N-acetylcysteine), and NSA9. These results suggest that NSA9 acts independently as an inhibitor of microglial activation and that its effects in EOC2 microglia are not influenced by the presence of kringle-2.

• International Journal of Oral Biology
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• 제40권2호
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• pp.71-77
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• 2015

The activation of glial cells in the spinal cord has been contribute to the initiation and maintenance of pain facilitation induced by peripheral inflammation and nerve injury. The present study investigated effects of botulinum toxin type A (BoNT-A), injected subcutaneously or intracisternally, on the expression of microglia and astrocytes in rats. Complete Freund's Adjuvant (CFA)-induced inflammation was employed as an orofacial chronic inflammatory pain model. A subcutaneous injection of $40{\mu}L$ CFA into the vibrissa pad was performed under 3% isoflurane anesthesia in SD rats. Immunohistochemical analysis for changes in Iba1 (a microglia marker) and GFAP (an astrocyte marker), were performed 5 days after CFA injection. Subcutaneous injection of CFA produced increases in Iba1 and GFAP expression, in the ipsilateral superficial lamia I and II in the medullary dorsal horn of rats. Subcutaneous treatment with BoNT-A attenuated the up-regulation of Iba1 and GFAP expressions induced by CFA injection. Moreover, intracisternal injection of BoNT-A also attenuated the up-regulated Iba1 and GFAP expressions. These results suggest that the anti-nociceptive action of BoNT-A is mediated by modulation activation of glial cells, including microglia and astrocyte.

• 한국식생활문화학회지
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• 제38권3호
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• pp.176-183
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• 2023

In this study, we investigated the effect of the extracts of Cyrtomium fortunei J.Sm. (CFJ) on lipopolysaccharide (LPS) induced inflammation in mouse BV-2 microglial cells. Nitric oxide (NO) production and cell viability were measured using the Griess reagent and the (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) (MTT) assay. Inflammatory cytokines were detected by quantitative polymerase chain reaction (qPCR) in BV-2 microglial cells with and without CFJ extracts. Subsequently, mitogen-activated protein kinases (MAPKs) and antioxidant markers were assessed by western blot analysis. It was found that the CFJ extract significantly decreased the production of pro-inflammatory cytokines (interleukin [IL]-6, tumor necrosis factor [TNF]-α, and IL-1β) and NO in BV-2 microglial cells that were stimulated with LPS. In addition, the expression levels of the phosphorylation of the MAPK family (p38, c-Jun N-terminal kinases [JNK], and extracellular-signal regulated kinase [ERK]) were reduced by CFJ. Also, treatment with CFJ significantly increased the activities of superoxide dismutase type 1(SOD1) and Catalase in BV-2 microglial cells. Our results indicate that CFJ has a potent suppressive effect on the pro-inflammatory responses of activated BV-2 microglia. Therefore, CFJ has the potential to be an effective treatment for neurodegenerative diseases, as it can inhibit the production of inflammatory mediators in activated BV-2 microglial cells.

• 대한본초학회지
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• 제24권4호
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• pp.173-179
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• 2009

Objectives : In this study, the effects of different fractions isolated from modified Boyanghwanotang(mBHT) extract on LPS-induced inflammation in BV2 microglial cells were investigated. Methods : mBHT was extracted with water, and then fractionated with n-hexane, methylene chloride, ethylacetate and n-butanol. BV2 cells, a mouse microglia line were incubated with different concentrations of each fraction of mBHT for 30 min, and then stimulated with LPS for 24 h. Cell toxicity was determined by MTT assay. The concentration of nitric oxide (NO) was measured in culture medium by Griess reagent assay. The expression of inducible nitric oxide synthease (iNOS) protein was determined by Western blot. Results : Four fractions of mBHT were significantly inhibited LPS-induced NO productions in BV2 cells in a dose-dependent manner. The methylene chloride fraction of mBHT was most strongly inhibited the NO production compared with those of the others. The methylene chloride fraction of mBHT was also suppressed LPS-induced iNOS expression comparison of other fractions at same concentration ($50\;{\mu}g/ml$) in BV2 cells. Conclusions : The results showed that the methylene chloride fraction of mBHT may have an strong anti-inflammatory property through the inhibition of NO production and iNOS expression in activated microglia, and could a therapeutic potential for the treatment of various brain inflammatory diseases.

• BMB Reports
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• 제49권12호
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• pp.687-692
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• 2016

We recently reported the anti-inflammatory effects of 3-(naphthalen-2-yl(propoxy)methyl)azetidine hydrochloride (KHG26792) on the ATP-induced activation of the NFAT and MAPK pathways through the P2X7 receptor in microglia. To further investigate the underlying mechanism of KHG26792, we studied its protective effects on hypoxia-induced toxicity in microglia. The administration of KHG26792 significantly reduced the hypoxia-induced expression and activity of caspase-3 in BV-2 microglial cells. KHG26792 also reduced hypoxia-induced inducible nitric oxide synthase protein expression, which correlated with reduced nitric oxide accumulation. In addition, KHG26792 attenuated hypoxia-induced protein nitration, reactive oxygen species production, and NADPH oxidase activity. These effects were accompanied by the suppression of hypoxia-induced protein expression of hypoxia-inducible factor 1-alpha and NADPH oxidase-2. Although the clinical relevance of our findings remains to be determined, these data results suggest that KHG26792 prevents hypoxia-induced toxicity by suppressing microglial activation.

• Genomics & Informatics
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• 제21권1호
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• pp.2.1-2.14
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• 2023

Microglia, similar to peripheral macrophages, are the primary immune cells of the central nervous system (CNS). Microglia exist in the resting state in the healthy CNS, but can be activated and polarized into either M1 or M2 subtypes for immune defense and the maintenance of CNS homeostasis by multiple stimuli. Several long noncoding RNAs (lncRNAs) mediate human inflammatory diseases and neuropathologies by regulating their target genes. However, the function of common lncRNAs that contribute to microglial activation remains unclear. Thus, we used bioinformatic approaches to identify common lncRNAs involved in microglial activation in vitro. Our study identified several lncRNAs as common regulators of microglial activation. We identified 283 common mRNAs and 53 common lncRNAs during mouse M1 microglial activation processes, whereas 26 common mRNAs and five common lncRNAs were identified during mouse M2 microglial activation processes. A total of 648 common mRNAs and 274 common lncRNAs were identified during the activation of human M1 microglia. In addition, we identified 1,920 common co-expressed pairs in mouse M1 activation processes and 25 common co-expressed pairs in mouse M2 activation processes. Our study provides a comprehensive understanding of common lncRNA expression profiles in microglial activation processes in vitro. The list of common lncRNAs identified in this study provides novel evidence and clues regarding the molecular mechanisms underlying microglial activation.

• International Journal of Oral Biology
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• 제45권2호
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• pp.33-41
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• 2020

Neuroinflammation is known as the main mechanism implicated in the advancement of neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease. The main feature of neuroinflammation is associated with the activation of microglia. The activated microglia increase proinflammatory cytokine production and induce progressive neuronal cell death. Citrus flavonoids show neuroprotective effects that are associated with the anti-inflammatory action of flavonoids in neurodegenerative diseases. Among these citrus flavonoids, kaempferol, naringin, and nobiletin show inhibitory effects on nuclear factor-κB and mitogen-activated protein kinase signaling pathways that can modulate inflammatory conditions in microglial cells. In the present review, we present the anti-inflammatory activities of citrus flavonoids and therapeutic potential of flavonoids as neuroprotective agents.

• 동의생리병리학회지
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• 제19권2호
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• pp.416-425
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• 2005

This study demonstrated neuroprotective and anti-oxidative effects of Puerariae Radix for cerebral ischemia. Neuroprotective effects were studied by using oxygen/glucous deprivation of the organotypic hippocampal slice cultures to complement limitations of in vivo and in vitro models for cerebral ischemia study. Anti-oxidative effects were studied on BV-2 microglia cells damaged by $H_2O_2$ and nitric oxide. The results obtained are as follows; The groups treated with 0.5 and $5{\mu}g/m{\ell}$ of Puerariae Radix revealed significant decreases of neuronal cell death area and cell death area percentages in CA1 region of ischemic damaged hippocampus cultures during whole 48 hours of the experiment. The groups treated with 0.5 and $5{\mu}g/m{\ell}$ of Puerariae Radix revealed significant decreases of neuronal cell death area and cell death area percentages in DG region of ischemic damaged hippocampus cultures during whole 48 hours of the experiment. The groups treated with 0.5 and $5{\mu}g/m{\ell}$ of Puerariae Radix revealed significant decreases of TUNEL-positive cells in both CA1 region and DG region of ischemic damaged hippocampus cultures. The group treated with $50\;{\mu}g/m{\ell}$ of Puerariae Radix demonstrated significant decrease of TUNEL-positive cells in CA1 region. The groups treated with 0.5 and $5{\mu}g/m{\ell}$ of Puerariae Radix revealed significant decreases of LDH concentrations in culture media of ischemic damaged hippocampus cultures. The groups treated with 0.5 and $5{\mu}g/m{\ell}$ of Puerariae Radix revealed significant increases of cell viabilities of BV-2 microglia cells damaged by $H_2O_2$. The group treated with $5{\mu}g/m{\ell}$ of Puerariae Radix revealed significant increase of cell viability of BV-2 microglia cells damaged by nitric oxide. These results suggested that Puerariae Radix of cerebral ischemic revealed neuroprotective effects through the control effect of apoptosis and oxidative damages.

• 대한한의학방제학회지
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• 제25권4호
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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.