• IMMUNE NETWORK
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• 제4권2호
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• pp.116-122
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• 2004

Background: LIGHT (TNFSF14) is a member of tumor necrosis factor superfamily and is the ligand for TR2 (TNFRSF14/HVEM). LIGHT is known to have proinflammatory roles in atherosclerosis. Methods: To find out the expression pattern of LIGHT in atherosclerotic plaques, immunohistochemical analysis was performed on human carotid atherosclerotic plaque specimens. LIGHT induced atherogenic events using human monocytic cell line THP-1 were also investigated. Results: Immunohistochemical analysis revealed expression of LIGHT and TR2 in foam cell rich regions in the atherosclerotic plaques. Double immunohistochemical analysis further confirmed the expression of LIGHT in foam cells. Stimulation of THP-1 cells, which express TR2, with either recombinant LIGHT or immobilized anti-TR2 monoclonal antibody induced interleukin-8 and matrix metalloproteinase(MMP)-9. Electrophoretic mobility shift assay demonstrated that LIGHT induces nuclear localization of transcription factor, nuclear factor $(NF)-{\kappa}B$. LIGHT induced activation of MMP-9 is mediated by $NF-{\kappa}B$, since treatment of THP-1 cells with the $NF-{\kappa}B$ inhibitor PDTC (pyrrolidine dithiocarbamate) completely blocked the activation of MMP-9. Conclusion: These data indicate that LIGHT is expressed in foam cells in atherosclerotic plaques and is involved in atherogenesis through activation of pro-atherogenic cytokine IL-8 and destabilization of plaque by inducing matrix degrading enzyme.

• Natural Product Sciences
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• 제24권1호
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• pp.28-35
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• 2018

Pulegone is a naturally occurring organic compound obtained from essential oils from a variety of plants. The aim of this study was to investigate the anti-inflammatory effects through the inhibitory mechanism of inducible nitric oxide synthase (iNOS), cyclooxygenase (COX-2), nuclear factor kappa B ($NF-{\kappa}B$), mitogen-activated protein kinases (MAPK) pathways and the activation of nuclear factor erythroid 2-related factor 2 (Nrf2)/ heme oxygenase (HO)-1 pathways in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Results revealed that pulegone significantly inhibited NO production as well as iNOS and COX-2 expressions. Meanwhile, western blot analysis showed that pulegone down-regulated LPS-induced $NF-{\kappa}B$ and MAPKs activation in RAW 264.7 cells. Furthermore, the selected compound suppressed LPS-induced intracellular ROS production in RAW 264.7 cells, while the expression of stress response gene, HO-1, and its transcriptional activator, Nrf-2 was upregulated upon pulegone treatment. Taking together, these findings provided that pulegone inhibited the LPS-induced expression of inflammatory mediators via the down-regulation iNOS, COX-2, $NF-{\kappa}B$, and MAPKs signaling pathways as well as up-regulation of Nrf-2/HO-1 indicating that pulegone has a potential therapeutic and preventive application in various inflammatory diseases.

• BMB Reports
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• 제50권2호
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• pp.103-108
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• 2017

Heme oxygenase (HO-1) catalyzes heme to carbon monoxide (CO), biliverdin/bilirubin, and iron and is known to prevent the pathogenesis of several human diseases. We assessed the beneficial effect of heme degradation products on osteoclastogenesis induced by receptor activator of NF-${\kappa}B$ ligand (RANKL). Treatment of RAW264.7 cells with CORM-2 (a CO donor) and bilirubin, but not with iron, decreased RANKL-induced osteoclastogenesis, with CORM-2 having a more potent anti-osteogenic effect. CORM-2 also inhibited RANKL-induced osteoclastogenesis and osteoclastic resorption activity in marrow-derived macrophages. Treatment with hemin, a HO-1 inducer, strongly inhibited RANKL-induced osteoclastogenesis in wild-type macrophages, but was ineffective in $HO-1^{+/-}$ cells. CORM-2 reduced RANKL-induced NFATc1 expression by inhibiting IKK-dependent NF-${\kappa}B$ activation and reactive oxygen species production. These results suggest that CO potently inhibits RANKL-induced osteoclastogenesis by inhibiting redox-sensitive NF-${\kappa}B$-mediated NFATc1 expression. Our findings indicate that HO-1/CO can act as an anti-resorption agent and reduce bone loss by blocking osteoclast differentiation.

• 생약학회지
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• 제46권3호
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• pp.195-202
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• 2015

Cnidium monnieri (L). Cussion is used as a tonic agent in traditional oriental medicine. However, the molecular mechanism of mast cell-mediated anti-inflammatory modulation has not been fully understood. The aim of the present study was to demonstrate the effects of Cnidium monnieri (L). Cussion eathyl acetate fraction on the expression of pro-inflammatory cytokines, as well as to elucidate its mechanism of action in the human mast cell line (HMC-1). Cells were stimulated with phorbol 12-myristate 13-acetate (PMA) plus A23187 in the presence or absence of Cnidium monnieri (L). Cussion eathyl acetate fraction. Cnidium monnieri (L). Cussion eathyl acetate fraction significantly inhibited the PMA plus A23187-induction of inflammatory cytokines such as tumor necrosis factor (TNF)-$\alpha$, interleukin (IL)-6 and IL-8. Moreover, EtOAc fraction attenuated cyclooxygenase (COX)-2 expression. In activated HMC-1 cells, phosphorylation of extra-signal response kinase (ERK) 1/2 decreased after treatment with EtOAc fraction. Moreover EtOAc fraction inhibited PMA plus A23187-induced nuclear factor (NF)-${\kappa}B$ activation, $I{\kappa}B$ degradation. EtOAc fraction suppressed the expression of TNF-$\alpha$, IL-6, IL-8 through a decrease in the ERK 1/2, as well as activation of NF-${\kappa}B$. These results indicated that Cnidium monnieri (L). Cussion EtOAc fraction exerted a regulatory effect on inflammatory reactions mediated by mast cells.

• 동의생리병리학회지
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• 제16권6호
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• pp.1284-1290
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• 2002

Scrophularia buergeriana Miquel (Scrophulariaceae) has been used as an anti-inflammatory drug in the folk medicine recipe and been proved its anti-inflammatory effect in the oriental medicine. Since nitric oxide (NO) and superoxide anion (O/sub 2//sup -/) are ones of the major inflammatory parameters, we studied the effect of aqueous extracts of Scrophularia buergeriana (SB) on NO and O/sub 2//sup -/ production in lipopolysaccharide (LPS)-stimulated mouse peritoneal macrophages. NO, O/sub 2//sup -/production and inducible NO synthase (iNOS) level were significantly reduced in LPS-activated macrophages by SB compared to those without. Electrophoretic mobility shift assay (EMSA) indicated that SB blocked the activation of NF-kB, which was considered to be a potential transcription factor for the iNOS expression. SB also blocked degradation of IkBα. Furthermore, IkB kinase alpha (IKKα), which phosphorylates serine residues of IkB directly, is inhibited by SB. These results suggest that SB could exert its anti-inflammatory actions by suppressing the activation of NF-kB through inhibition of IKK activity.

• Biomolecules & Therapeutics
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• 제23권1호
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• pp.39-44
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• 2015

Tolfenamic acid (TA) is a traditional non-steroid anti-inflammatory drug (NSAID) and has been broadly used for the treatment of migraines. Nuclear factor kappa B (NF-${\kappa}B$) is a sequence-specific transcription factor and plays a key role in the development and progression of inflammation and cancer. We performed the current study to investigate the underlying mechanisms by which TA suppresses inflammation focusing on NF-${\kappa}B$ pathway in TNF-${\alpha}$ stimulated human normal and cancer cell lines and lipopolysaccharide (LPS)-stimulated mouse macrophages. Different types of human cells (HCT116, HT-29 and HEK293) and mouse macrophages (RAW264.7) were pre-treated with different concentrations of TA and then exposed to inflammatory stimuli such as TNF-${\alpha}$ and LPS. Transcriptional activity of NF-${\kappa}B$, $l{\kappa}B-{\alpha}$-degradation, p65 translocation and mitogen-activated protein kinase (MAPK) activations were measured using luciferase assay and Western blots. Pre-treatment of TA repressed TNF-${\alpha}$- or LPS-stimulated NF-${\kappa}B$ transactivation in a dose-dependent manner. TA treatment reduced degradation of $l{\kappa}B-{\alpha}$ and subsequent translocation of p65 into nucleus. TA significantly down-regulated the phosphorylation of c-Jun N-terminal kinase (JNK). However, TA had no effect on NF-${\kappa}B$ signaling and JNK phosphorylation in HT-29 human colorectal cancer cells. TA possesses anti-inflammatory activities through suppression of JNK/NF-${\kappa}B$ pathway in different types of cells.

• BMB Reports
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• 제49권1호
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• pp.57-62
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• 2016

Up-regulation of adhesion molecules plays an important role in the infiltration of leukocytes into the skin during the development of various inflammatory skin diseases, such as atopic dermatitis. In this study, we investigated the modulatory effects of 2,3-dimethoxy-2′-hydroxychalcone (DMHC) on tumor necrosis factor (TNF)-α-induced intercellular adhesion molecule-1 (ICAM-1) expression and monocyte adhesiveness, as well as the molecular mechanisms underlying its action in the HaCaT human keratinocyte cell line. Pre-treating HaCaT cells with DMHC significantly suppressed TNF-α-induced ICAM-1 expression and subsequent monocyte adhesiveness. DMHC inhibited TNF-α-induced activation of NF-ᴋB. In addition, DMHC induced HO-1 expression as well as NRF2 activation. Furthermore, HO-1 knockdown using siRNA reversed the inhibitory effect of DMHC on TNF-α-induced ICAM-1 expression and adhesion of monocytes to keratinocytes. These results suggest that DMHC may inhibit TNF-α-induced ICAM-1 expression and adhesion of monocytes to keratinocytes by suppressing the signaling cascades leading to NF-ᴋB activation and inducing HO-1 expression in keratinocytes. [BMB Reports 2016; 49(1): 57-62]

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제34권1호
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• pp.28-35
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• 2008

Purpose: The nitric oxide (NO) release by inducible nitric oxide synthase (iNOS) is the key events in macrophage response to lipopolysaccharide (LPS) which is suggested to be a crucial mediator for inflammatory and innate immune responses. NO is an important mediator involved in many host defense action and may also lead to a harmful host response to bacterial infection. However, given the importance of iNOS in a variety of pathophysiological conditions, control of its expression and signaling events in response to LPS has been the subject of considerable investigation. Materials and Methods: The Raw264.7 macrophage cell line was used to observe LPS-stimulated iNOS expression. The expression of iNOS is observed by Western blot analysis and real-time RT-PCR. Protein kinase C $(PKC)-{\alpha}$ overexpressing Raw264.7 cells are established to determine the involvement of $PKC-{\alpha}$ in LPS-mediated iNOS expression. $NF-{\kappa}B$ activity is measured by $I{\kappa}B{\alpha}$ degradation and $NF-{\kappa}B$ luciferase activity assay. Results: We found that various PKC isozymes regulate LPS-induced iNOS expression at the transcriptional and translational levels. The involvement of $PKC-{\alpha}$ in LPS-mediated iNOS induction was further confirmed by increased iNOS expression in $PKC-{\alpha}$ overexpressing cells. $NF-{\kappa}B$ dependent transactivation by LPS was observed and $PKC-{\alpha}$ specific inhibitory peptide abolished this activation, indicating that $NF-{\kappa}B$ activation is dependent on $PKC-{\alpha}$. Conclusion: Our data suggests that $PKC-{\alpha}$ is involved in LPS-mediated iNOS expression and that its downstream target is $NF-{\kappa}B$. Although $PKC-{\alpha}$ is a crucial mediator in the iNOS regulation, other PKC isozymes may contribute LPS-stimulated iNOS expression. This finding is needed to be elucidated in further study.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2020년도 추계국제학술대회
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• pp.3-13
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• 2020

Pseudomonas aeruginosa is a ubiquitous gram-negative bacterium causing serious infections. The P. aeruginosa T3SS is a syringe-like apparatus on the bacterial surface, with 4 effector toxins: ExoS, ExoT, ExoY, and ExoU. Here, we investigated the effect of ExoS and ExoT of the T3SS of P. aeruginosa K strain (PAK). The type three secretion system (T3SS) is a major virulence system of Pseudomonas aeruginosa (P. aeruginosa). The effector protein Exotoxin S (ExoS) produced by P. aeruginosa is secreted into the host cells via the T3SS. For the purpose of screening the inhibitors with regard to ExoS secretion, we developed the sandwich-type enzyme-linked immunosorbent assay (ELISA) system. PAK clinical strains induce proinflammatory cytokine production through the T3SS, and this involves NF-κB activation in pneumonia mouse models. We tried to confirm the role of the NF-κB transcription factor in ExoS- and ExoT-induced pneumonia mouse models. pro-inflammatory cytokines induction in response to ExoS and ExoT infection relied on NF-κB activation. Our findings highlight the roles of natural poduct in inhibiting proinflammatory cytokine expression during ExoS and ExoT exposure in PAK infections, paving the way for a novel therapeutic approach for the treatment of pulmonary infections.

• Nutrition Research and Practice
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• 제10권3호
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• pp.251-258
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• 2016

BACKGROUND/OBJECTIVES: Several pharmacological properties of red rice extract have been reported including anti-oxidant, anti-tumor, and reduced cancer cell invasion. This study was conducted to evaluate the anti-inflammatory effects of red rice extract on the production of inflammatory mediators in lipopolysaccharide (LPS)-induced Raw 264.7 macrophages. MATERIALS/METHODS: Pro-inflammatory cytokines including tumor necrosis factor-${\alpha}$ and interleukin-6 were determined by ELISA and cyclooxygenase-2 and inducible nitric oxide synthase expression was evaluated using western blot analysis. In addition, the signaling pathway controlling the inflammatory cascade such as nuclear factor kappa B ($NF-{\kappa}B$), activator proteins-1 (AP-1), and mitogen-activated protein kinase (MAPK) was determined. RESULTS: Our results showed that red rice polar extract fraction (RR-P), but not non-polar extract fraction, inhibited interleukin-6, tumor necrosis factor-${\alpha}$, and nitric oxide production in LPS-induced Raw 264.7 cells. RR-P also reduced the expression of inflammatory enzymes, inducible nitric oxide synthase, and cyclooxygenase-2. In addition, activation of AP-1 and $NF-{\kappa}B$ transcription factor in the nucleus was abrogated by RR-P. RR-P inhibited the phosphorylation of extracellular signaling-regulated kinase 1/2, c-Jun NH2-terminal kinase, and p38 MAPK signaling responsible for the expression of inflammatory mediators in LPS-stimulated Raw 264.7 cells. Based on chemical analysis, high amounts of proanthocyanidin and catechins were detected in the RR-P fraction. However, only proanthocyanidin reduced $NF-{\kappa}B$ and AP-1 activation in LPS-activated Raw 264.7 cells. CONCLUSION: These observations suggest that the anti-inflammatory properties of RR-P may stem from the inhibition of pro-inflammatory mediators via suppression of the AP-1, $NF-{\kappa}B$, and MAPKs pathways.