• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제33권3호
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• pp.227-237
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• 2007

Microglial cell activation is known to contribute to neuropathic pain following spinal sensory nerve injuries. In this study, I investigated its mechanisms in the case of trigeminal sensory nerve injuries by which microglial cell and p38 mitogen-activated protein kinase (p38 MAPK) activation in the medullary dorsal horn (MDH) would contribute to the facial pain hypersensitivity following mandibular nerve transection (MNT). And also investigated the changes of trigeminal ganglion neurons and ERK, p38 MAPK manifestations. Activation of microglial cells was monitored at 1, 3, 7, 14, 28 and 60 day using immunohistochemical analyses. Microglial cell activation was primarily observed in the superficial laminae of the MDH. Microglial cell activation was initiated at postoperative 1 day, maximal at 3 day, maintained until 14 day and gradually reduced and returned to the basal level by 60 days after MNT. Pain hypersensitivity was also initiated and attenuated almost in parallel with microglial cell activation pattern. To investigate the contribution of the microglial cell activation to the pain hypersensitivity, minocycline, an inhibitor of microglial cell activation by means of p38 MAPK inhibition, was administered. Minocycline dose-dependently attenuated the development of the pain hypersensitivity in parallel with inhibition of microglial cell and p38 MAPK activation following MNT. Mandibular nerve transection induced the activation of ERK, but did not p38 MAPK in the trigeminal ganglion. These results suggest that microglial cell activation in the MDH and p38 MAPK activation in the hyperactive microglial cells play an important role in the development of facial neuropathic pain following MNT. The results also suggest that ERK activation in the trigeminal ganglion contributes microglial cell activation and facial neuropathic pain.

• 한국가금학회지
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• 제44권3호
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• pp.199-209
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• 2017

Mitogen-activated protein kinase (MAPK) signaling pathways play a key role in innate immunity, inflammation, cell proliferation, cell differentiation, and cell death. The main objective of this study was to investigate the expression level of candidate MAPK pathway genes in the intestinal mucosal layer of two genetically disparate chicken lines (Marek's disease-resistant line 6.3 and Marek's disease-susceptible line 7.2) induced with necrotic enteritis (NE). Using high-throughput RNA sequencing, we investigated 178 MAPK signaling pathway related genes that were significantly and differentially expressed between the intestinal mucosal layers of the NE-afflicted and control chickens. In total, 15 MAPK pathway genes were further measured by quantitative real-time PCR(qRT-PCR) and the results were consistent with the RNA-sequencing data. All 178 identified genes were annotated through Gene Ontology and mapped onto the KEGG chicken MAPK signaling pathway. Several key genes of the MAPK pathway, ERK1/2, JNK1-3, p38 MAPK, MAP2K1-4, $NF-{\kappa}B1/2$, c-Fos, AP-1, Jun-D, and Jun, were differentially expressed in the two chicken lines. Therefore, we believe that RNA sequencing and qRT-PCR analysis provide resourceful information for future studies on MAPK signaling of genetically disparate chicken lines in response to pathogens.

• Biomolecules & Therapeutics
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• 제24권1호
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• pp.25-32
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• 2016

Lichens have been known to possess multiple biological activities, including anti-proliferative and anti-inflammatory activities. Vascular cell adhesion molecule-1 (VCAM-1) may play a role in the development of atherosclerosis. Hence, VCAM-1 is a possible therapeutic target in the treatment of the inflammatory disease. However, the effect of lobaric acid on VCAM-1 has not yet been investigated and characterized. For this study, we examined the effect of lobaric acid on the inhibition of VCAM-1 in tumor necrosis factor-alpha (TNF-${\alpha}$)-stimulated mouse vascular smooth muscle cells. Western blot and ELISA showed that the increased expression of VCAM-1 by TNF-${\alpha}$ was significantly suppressed by the pre-treatment of lobaric acid ($0.1-10{\mu}g/ml$) for 2 h. Lobaric acid abrogated TNF-${\alpha}$-induced NF-${\kappa}B$ activity through preventing the degradation of $I{\kappa}B$ and phosphorylation of extracellular signal-regulated kinases (ERK), c-Jun N-terminal kinases (JNK), and p38 mitogen activated protein (MAP) kinase. Lobaric acid also inhibited the expression of TNF-${\alpha}$ receptor 1 (TNF-R1). Overall, our results suggest that lobaric acid inhibited VCAM-1 expression through the inhibition of p38, ERK, JNK and NF-${\kappa}B$ signaling pathways, and downregulation of TNF-R1 expression. Therefore, it is implicated that lobaric acid may suppress inflammation by altering the physiology of the atherosclerotic lesion.

• Biomolecules & Therapeutics
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• 제26권2호
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• pp.210-217
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• 2018

Neuroinflammation is an immune response within the central nervous system against various proinflammatory stimuli. Abnormal activation of this response contributes to neurodegenerative diseases such as Parkinson disease, Alzheimer's disease, and Huntington disease. Therefore, pharmacologic modulation of abnormal neuroinflammation is thought to be a promising approach to amelioration of neurodegenerative diseases. In this study, we evaluated the synthetic flavone derivative 3',4'-dihydroxyflavone, investigating its anti-neuroinflammatory activity in BV2 microglial cells and in a mouse model. In BV2 microglial cells, 3',4'-dihydroxyflavone successfully inhibited production of chemokines such as nitric oxide and prostaglandin $E_2$ and proinflammatory cytokines such as tumor necrosis factor alpha, interleukin 1 beta, and interleukin 6 in BV2 microglia. It also inhibited phosphorylation of mitogen-activated protein kinase (MAPK) and nuclear factor $(NF)-{\kappa}B$ activation. This indicates that the anti-inflammatory activities of 3',4'-dihydroxyflavone might be related to suppression of the proinflammatory MAPK and $NF-{\kappa}B$ signaling pathways. Similar anti-neuroinflammatory activities of the compound were observed in the mouse model. These findings suggest that 3',4'-dihydroxyflavone is a potential drug candidate for the treatment of microglia-related neuroinflammatory diseases.

• 대한본초학회지
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• 제31권5호
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• pp.1-6
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• 2016

Objectives : Nardostachys jatamansi (NJ) is a medicinal herb that has been reported in various traditional systems of medicine for its use in antispasmodic, a digestive stimulant, skin diseases. Previous studies have already reported that NJ effectively protects against inflammation. However, the active compound in NJ is unknown. Therefore, in the present study, we analyzed effects of a compound, 8α-hydroxy pinoresinol (HP), isolated from NJ against lipopolysaccharide (LPS) induced inflammation in RAW 264.7 cells.Methods : To examine the anti-inflammatory effect of HP against LPS, intraperitoneally pre-treat the HP (100, 200, 500 and 1,000 nM) 1 h prior to LPS challenges. LPS was stimulated with 500 ng/ml in RAW 264.7 cells. To identify the anti-inflammatory effect of HP, we measured inflammatory mediators such as inducible nitric oxide synthase (iNOS) and its derivative nitric oxide (NO), cyclooxygenase-2 (COX-2), prostaglandin E2 (PGE2). Also we evaluated molecular mechanisms including mitogen-activated protein kinases (MAPKs) and nuclear factor-kappaB (NF-κB) activation by western blot.Results : The HP inhibited production of inflammatory mediators, such as iNOS and its derivative NO, COX-2 and PGE2 in LPS- induced inflammationin RAW 264.7 cells. Additionally, HP also inhibited activation of p38 pathway signaling but not extracellularsignal-regulatedkinase (ERK), c-jun NH2-terminal kinase (JNK), and NF-κB.Conclusion : Our results suggest that HP has anti-inflammatory functions through the dephosphorylation of p38 and HP can provide beneficial strategy for prevention and therapy of inflammation.

• 대한본초학회지
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• 제26권3호
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• pp.23-29
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• 2011

Objective : The purpose of this study was to investigate the anti-inflammatory effects of aqueous extract from Scolopendrae Corpus (SC) on lipopolysaccharide (LPS)-induced inflammatory response. Methods : To evaluate the anti-inflammatory effects of SC, we examined the inflammatory mediators such as nitric oxide (NO) and pro-inflammatory cytokines (TNF-a, inteleukin (IL)-$1{\beta}$ and IL-6) on RAW 264.7 cells. We also examined molecular mechanisms such as mitogen-activated protein kinases (MAPKs) and inhibitory kappa B a ($I{\kappa}$-Ba) using western blot. Furthermore, we also investigated the effect of SC on LPS-induced endotoxin shock. Results : Extract from SC itself had not any cytotoxic effect in RAW 264.7 cells. Aqueous extract from SC inhibited LPS-induced NO production and iNOS expression. SC pre-treatment also inhibited IL-$1{\beta}$, IL-6 production in RAW 264.7 cells. To investigate inhibitory effects of SC on inflammatory mediators, activation of MAPKs was examined. SC inhibited the phosphorylation of p38 kinases (p38), c-Jun $NH_2$-terminal kinase (JNK) and also the degradation of $I{\kappa}$-$B{\alpha}$ in RAW 264.7 cells stimulated with LPS. Furthermore, SC administration reduced LPS-induced endotoxin shock. Conclusion : SC down-regulated LPS-induced production of inflammatory mediators through inhibition of activation of p38, JNK and degradation of $I{\kappa}$-$B{\alpha}$. Taken together, our results suggest that SC may be a beneficial drug against inflammatory diseases such as sepsis.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2018년도 춘계학술대회 및 임시총회
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• pp.11-11
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• 2018

Cryphonectria parasitica, chestnut blight fungus, has a characteristic of decreasing pathogenicity when infected with Cryphonectria hypovirus 1. C. parasitica is known to be one of the most representative model systems used to observe the interaction between viruses, plants and fungi. The mitogen-activated protein kinase (MAPK) pathway, which is well conserved in various organisms ranging from yeast to humans, functions in relaying phosphorylation-dependent signals within MAPK cascades to diverse cellular functions involved in the regulation of pheromone, cell wall integrity, and osmotolerance in filamentous fungi. Several genes in the MAPK pathway were revealed to be regulated by hypovirus, or to be involved in pathogenicity in C. parasitica. Among these pathways, the CWI pathway has aroused interest because CpBck1, an ortholog of yeast Bck1 (a CWI MAPKKK), was previously reported to be involved in cell wall integrity and sectorization. Interestingly, sporadic sectorization was observed in the CpBck1 mutant and sectored phenotypes were stably inherited in the progeny that were successively transferred from sectored mycelia. In this study, we analyzed the biological function of CpSlt2, downstream gene of CpBck1, to confirm whether the sectorization phenomenon occurred in the specific single gene or cell wall integrity (CWI) pathway. As results, the CpSlt2-null mutant exhibited marked changes in colonial growth, near absence of conidiation and aerial hyphae, abnormal pigmentation, CWI-related phenotypic defects, and dramatically impaired virulence. As cultivation of the mutant strains progressed, the majority of the colonies showed sporadic sectorization and mycelia from the sectored area stably maintained the sectored phenotype. These results suggest that the unique sectorization is CWI pathway-specific, though the components in the same CWI pathway have common and specific functions.

• Environmental Analysis Health and Toxicology
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• 제21권3호
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• pp.275-282
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• 2006

In order to get insight into the mechanism of cadmium (Cd)-induced brain injury, we investigated the effects of Cd on the induction of COX-2 in bEnd.3 mouse brain endothelial cells. Cd induced COX-2 expression and $PGE_2$ release, which were attenuated by thiol-reducing antioxidant N-acetylcysteine (NAC) indicating oxidative components might contribute to these events. Indeed, Cd increased cellular reactive oxygen species (ROS) level and DNA binding activity of nuclear factor-kB (NF-kB), an oxidative stress sensitive transcription factor. Cd-induced $PGE_2$ production and COX-2 expression were significantly attenuated by Bay 11 7082, a specific inhibitor of NF-kB and by SB203580, a specific inhibitor of p38 mitogen activated protein kinase (MAPK). These data suggest that Cd induces COX-2 expression through activation of NF-kB and p38 MAPK, the oxidative stress-sensitive signaling molecules, in brain endothelial cells.

• IMMUNE NETWORK
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• 제13권6호
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• pp.283-288
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• 2013

The pro-inflammatory cytokines tumor necrosis factor-${\alpha}$ (TNF${\alpha}$) and interleukin (IL)-$1{\beta}$ are crucial mediators involved in chronic inflammatory diseases. Inflammatory signal pathways regulate inflammatory cytokine expression-mediated by p38 mitogen activated protein kinase (p38MAPK). Therefore, considerable attention has been given to p38MAPK as a target molecule for the development of a novel anti-inflammatory therapeutics. BIRB 796, one of p38MAPK inhibitor, is a candidate of therapeutic drug for chronic inflammatory diseases. In this study, we investigated the effect of BIRB 796 on inflammatory cytokine productions by lipopolysaccharide (LPS) in different immune cell types. BIRB 796 reduced LPS-mediated IL-8 production in THP-1 cells but not in Raw 264.7 cells. Further analysis of signal molecules by western blot revealed that BIRB 796 sufficiently suppressed LPS-mediated phosphorylation of p38MAPK in both cell types whereas it failed to block inhibitor of kappa B (I-${\kappa}B$) degradation in Raw 264.7 cells. Taken together, these results suggest that the anti-inflammatory function of BIRB 796 depends on cell types.

• The Korean Journal of Physiology and Pharmacology
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• 제16권6호
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• pp.431-436
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• 2012

Dioscorea species continue to be used in traditional Chinese medicine, and represent a major source of steroid precursors for conventional medicine. In the previous study, We isolated glycoprotein (GDB) from Dioscorea batatas, characterized, and demonstrated immunostimulating activity in C57BL/6 mice. The aim of this study was to investigate the mechanism whereby GDB activates macrophages. Macrophages activation by GDB was investigated by analyzing the effects of GDB on nitric oxide (NO) production, iNOS expression, mitogen activated protein kinase (MAPK) phosphorylation, and transcription factor activation. In the presence of IFN-${\gamma}$, GDB strongly stimulated macrophages to express iNOS and produce NO. Furthermore, the activation of p38 was synergistically induced by GDB plus IFN-${\gamma}$, but SB203580 (a p38 inhibitor) inhibited GDB plus IFN-${\gamma}$-induced p38 activation. This study indicates that GDB is an important activator of macrophages. Furthermore, due to the critical role that macrophage activation plays in innate immune response, the activation effects of GDB on macrophages suggest that GDB may be a useful immunopotentiating agent.