• BMB Reports
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• 제50권1호
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• pp.25-30
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• 2017

In the central nervous system, viral infection can induce inflammation by up-regulating pro-inflammatory mediators that contribute to enhanced infiltration of immune cells into the central nervous areas. Celastrol is known to exert various regulatory functions, including anti-microbial activities. In this study, we investigated the regulatory effects and the mechanisms of action of celastrol against astrocytes activated with polyinosinic-polycytidylic acid (poly(I:C)), a synthetic dsRNA, as a model of pro-inflammatory mediated responses. Celastrol significantly inhibited poly(I:C)-induced expression of adhesion molecules, such as ICAM-1/VCAM-1, and chemokines, such as CCL2, CXCL8, and CXCL10, in CRT-MG human astroglioma cells. In addition, celastrol significantly suppressed poly(I:C)-induced activation of JNK MAPK and STAT1 signaling pathways. Furthermore, celastrol significantly suppressed poly(I:C)-induced activation of the $NF-{\kappa}B$ signaling pathway. These results suggest that celastrol may exert its regulatory activity by inhibiting poly(I:C)-induced expression of pro-inflammatory mediators by suppressing activation of JNK MAPK-STAT1/$NF-{\kappa}B$ in astrocytes.

• Biomolecules & Therapeutics
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• 제22권4호
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• pp.288-294
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• 2014

Mangostenone F (MF) is a natural xanthone isolated from Garcinia mangostana. However, little is known about the biological activities of MF. This study was designed to investigate the anti-inflammatory effect and underlying molecular mechanisms of MF in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. MF dose-dependently inhibited the production of NO, iNOS, and pro-inflammatory cytokines (TNF-${\alpha}$, IL-6, and IL-$1{\beta}$) in LPS-stimulated RAW264.7 macrophages. Moreover, MF decreased the NF-${\kappa}B$ luciferase activity and NF-${\kappa}B$ DNA binding capacity in LPS-stimulated RAW264.7 macrophages. Furthermore, MF suppressed the NF-${\kappa}B$ activation by inhibiting the degradation of $I{\kappa}B{\alpha}$ and nuclear translocation of p65 subunit of NF-${\kappa}B$. In addition, MF attenuated the AP-1 luciferase activity and phosphorylation of ERK, JNK, and p38 MAP kinases. Taken together, these results suggest that the anti-inflammatory effect of MF is associated with the suppression of NO production and iNOS expression through the down-regulation of NF-${\kappa}B$ activation and MAPK signaling pathway in LPS-stimulated RAW264.7 macrophages.

• BMB Reports
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• 제56권6호
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• pp.359-364
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• 2023

KAI1/CD82, a membrane tetraspanin protein, can prevent various cancers and retinal disorders through its anti-angiogenic and anti-metastatic capacity. However, little is known about its anti-inflammatory effect and molecular mechanism. Therefore, the present study aimed to inLPSvestigate effect of a recombinant protein of the large extracellular domain of human KAI1 (Gly 111-Leu 228, rhKAI1) on lipopolysaccharides (LPS)-stimulated RAW264.7 macrophage-like cells and mouse bone marrow-derived macrophages (BMDM) and to identify its underlying mechanism. Our data showed that rhKAI1 suppressed expression levels of classically macrophages (M1) phenotype-related surface markers F4/80+CD86+ in LPS-stimulated BMDM and RAW264.7 cells. In addition, LPS markedly increased mRNA expression and release levels of pro-inflammatory cytokines and mediators such as interleukin (IL)-1β, IL-6, tumor necrosis factor-α, cyclooxygenase-2, nitric oxide and prostaglandin E2, whereas these increases were substantially down-regulated by rhKAI1. Furthermore, LPS strongly increased expression of NF-κB p65 in the nuclei and phosphorylation of ERK, JNK, and p38 MAPK. However, nuclear translocation of NF-κB p65 and phosphorylation of JNK were greatly reversed in the presence of rhKAI1. Especially, rhKAI1 markedly suppressed expression of toll-like receptor (TLR4) and prevented binding of LPS with TLR4 through molecular docking predict analysis. Importantly, Glu 214 of rhKAI1 residue strongly interacted with Lys 360 of TLR4 residue, with a binding distance of 2.9 Å. Taken together, these findings suggest that rhKAI1 has an anti-inflammatory effect on LPS-polarized macrophages by interacting with TLR4 and down-regulating the JNK/NF-κB signaling pathway.

• International Journal of Oral Biology
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• 제45권4호
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• pp.169-178
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• 2020

L-ascorbic acid (L-AA; vitamin C) induces apoptosis in cancer cells. This study aimed to elucidate the molecular mechanisms of L-AA-induced apoptosis in human laryngeal epidermoid carcinoma Hep-2 cells. L-AA suppressed the viability of Hep-2 cells and induced apoptosis, as shown by the cleavage and condensation of nuclear chromatin and increased number of Annexin V-positive cells. L-AA decreased Bcl-2 protein expression but upregulated Bax protein levels. In addition, cytochrome c release from the mitochondria into the cytosol and activation of caspase-9, -8, and -3 were enhanced by L-AA treatment. Furthermore, apoptosis-inducing factor (AIF) and endonuclease G (EndoG) were translocated into the nucleus during apoptosis of L-AA-treated Hep-2 cells. L-AA effectively inhibited the constitutive nuclear factor-κB (NF-κB) activation and attenuated the nuclear expression of the p65 subunit of NF-κB. Interestingly, L-AA treatment of Hep-2 cells markedly activated Akt and mitogen-activated protein kinase (MAPK; extracellular signal-regulated kinase 1/2, p38, and c-Jun N-terminal kinase [JNK]) and and LY294002 (Akt inhibitor), SB203580 (p38 inhibitor) or SP600125 (a JNK inhibitor) decreased the levels of Annexin V-positive cells. These results suggested that L-AA induces the apoptosis of Hep-2 cells via the nuclear translocation of AIF and EndoG by modulating the Bcl-2 family and MAPK/Akt signaling pathways.

• 한방안이비인후피부과학회지
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• 제25권3호
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• pp.1-12
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• 2012

Objectives : Fagopyrum esculentum(FE) has been used for removal of inflammation of internal organs and treatment of sore and ulcer by heat toxin in Korean herbal medicines. In this study, To investigated the protective effect of FE on allergic response, we determined whether FE inhibits allergic response. Methods : The effect of FE was analyzed by ELISA, RT-PCR and Western blot in RBL-2H3 cells. We investigated cell viability, ${\beta}$-hexosaminidase, as a marker of degranulation, cytokne, and intracellular ROS and MAPK and NF-${\kappa}B$ signaling. Results : We found that FE suppressed ${\beta}$-hexosaminidase release, the production of IL-4 and TNF-${\alpha}$ and intracellular ROS level in RBL-2H3 by the anti-DNP IgE plus DNP-HSA stimulation. FE also significantly inhibited cytokine mRNA expressions, such as IL-$1{\beta}$, IL-2, IL-3, IL-4, IL-5, IL-6, IL-13, TNF-${\alpha}$ and GM-CSF in RBL-2H3. In addition, PF suppressed the phospholyation of ERK1/2, JNK1/2, p38 and $I{\kappa}B{\alpha}$ and NF-${\kappa}B$ signal transduction pathway. Conclusions : Our results indicate that FE protects against allergic response and exerts an anti-inflammatory effect through the inhibition of degranulation and production of cytokines and ROS via the suppression MAPK and NF-${\kappa}B$ of signal transduction. Abbrevations : FE, Fagopyrum esculentum; RBL-2H3, rat basophilic leukemia cell line; ROS, reactive oxygen species; MAPK, Mitogen-activated protein kinase; $NF{\kappa}B$, nuclear factor ${\kappa}B$; $TNF{\alpha}$, Tumor necrosis factor alpha; GM-CSF, Granulocyte macrophage colony-stimulating factor; ERK, extracellular-signal-regulated kinase; JNK, c-Jun NH2-terminal kinase; p38, p38 MAP kinase; $I{\kappa}B{\alpha}$, inhibitory-kappa B alpha.

• IMMUNE NETWORK
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• 제11권4호
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• pp.216-222
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• 2011

Background: The ligand for CD137 (CD137L; also called 4-1BBL) is mainly expressed on activated APCs such as dendritic cells, B cells and macrophages. Even though CD137L functions as a trigger of the CD137 signaling pathway for T cell activation and expansion, engagement of CD137L can deliver a signal leading to the production of proinflammatory cytokines in macrophages. Methods: We generated cell-permeable TAT-CD137L cytoplasmic domain fusion protein (TAT-CD137Lct) and examined its ability to initiate the CD137L reverse signaling pathway. Results: Treatment of TAT-CD137Lct induced the production of high levels of IL-6 and TNF-${\alpha}$ mRNAs and proteins in peritoneal macrophages. TAT-CD137Lct increased phosphorylation of Erk, p38 MAPK and Jnk, and activated transcription factors C/EBP and CREB. However, TAT-CD137Lct did not visibly affect the degradation of the inhibitor of NF-${\kappa}B$ ($IkB{\alpha}$). We further demonstrated that JNK activation was required for TAT-CD137Lct-induced production of TNF-${\alpha}$, while activation of Erk and p38 MAPK were involved in IL-6 and TNF-${\alpha}$ production. Conclusion: Our results suggest that TATCD137Lct is an effective activator for the CD137L reverse signaling pathway.

• Journal of Ginseng Research
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• 제45권2호
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• pp.354-360
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• 2021

Background: Protopanaxatriol (PPT) is a secondary intestinal metabolite of ginsenoside in ginseng. Although the effects of PPT have been reported in various diseases including cancer, diabetes and inflammatory diseases, the skin protective effects of PPT are poorly understood. Methods: HaCaT cells were treated with PPT in a dose-dependent manner. mRNA and protein levels which related to skin barrier and hydration were detected compared with retinol. Luciferase assay was performed to explore the relative signaling pathway. Western blot was conducted to confirm these pathways and excavated further signals. Results: PPT enhanced the expression of filaggrin (FLG), transglutaminase (TGM)-1, claudin, occludin and hyaluronic acid synthase (HAS) -1, -2 and -3. The mRNA expression levels of FLG, TGM-1, HAS-1 and HAS-2 were suppressed under NF-κB inhibition. PPT significantly augmented NF-κB-luc activity and upregulated Src/AKT/NF-κB signaling. In addition, PPT also increased phosphorylation of the mitogen-activated protein kinases (MAPKs) ERK, JNK and p38 and upstream MAPK activators (MEK and MKK). Furthermore, transcriptional activity of AP-1 and CREB, which are downstream signaling targets of MAPK, was enhanced by PPT. Conclusion: PPT improves skin barrier function and hydration through Src/AKT/NF-κB and MAPK signaling. Therefore, PPT may be a valuable component for cosmetics or treating skin disorders.

• 생명과학회지
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• 제32권11호
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• pp.899-907
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• 2022

Quercetin은 과일과 채소에 풍부한 플라보노이드 중의 하나로써, 항산화, 항염증, 항암, 항바이러스 활성 등 다양한 약리학적 활성을 가지고 있는 것으로 알려져 있다. 본 연구에서는 in vitro 모델에서 quercetin의 항염증 활성과 작용기전을 연구하였다. Quercetin은 LPS로 자극된 RAW264.7에서 세포 생존율에 영향 없이 NO 생산을 농도 의존적으로 저해하였고, iNOS와 COX-2 단백질의 발현을 억제하였다. 게다가, quercetin은 LPS로 유도된 p38, JNK, ERK의 인산화를 농도 의존적으로 저해하였고, NF-κB p65 단백질과 억제자인 IκBα 단백질의 인산화를 저해하였다. 이러한 결과는 quercetin의 항염증 활성이 MAPK 경로와 NF-κB를 조절함으로써 이루어진다는 것을 시사한다. Quercetin에 의해 4종류의 친 염증성 cytokine (CSF2, IL-1β, IL-6, TNF-α)의 발현 변화를 정량적 real-time PCR 방법으로 확인한 결과, 모든 cytokine 유전자의 발현이 감소됨을 확인하였다. 종합적으로, 본 연구결과는 플라보노이드 quercetin이 RAW264.7 세포에서 LPS로 유도된 염증반응을 MAPK 경로와 NF-κB경로를 통해 억제하고 친염증성 cytokine 유전자의 발현을 억제함으 로써 조절한다는 것을 제시한다.

• 생약학회지
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• 제48권2호
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• pp.155-159
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• 2017

Cudrania tricuspidata Bureau (Moraceae) is a traditional oriental medicine that has been widely used as anti-oxidant, anti-inflammatory and immunomodulatory in Korea. This study was performed that the 70% ethanol extract of the roots of C. tricuspidata (CTE) suppressed receptor activator of NF-${\kappa}B$ ligand (RANKL)-induced osteoclastogenesis, actin ring formation in RAW 264.7 cell lines. CTE significantly inhibited the JNK/mitogen-activated protein kinase (MAPK) signaling pathway without affecting ERK and p38 signaling in RANKL-stimulated RAW 264.7 cells. Also, CTE inhibited RANKL-induced expression of c-Fos, an upstream activator of NFATc1. Consequently, CTE suppresses osteoclast differentiation by inhibiting RANKL induced MAPK signaling pathways and disrupts the actin rings in mature osteoclasts. Thus, CTE can be used for the development of osteoporosis treatment drug with a natural material.

• 한국식품과학회지
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• 제50권5호
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• pp.555-563
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• 2018

보리는 높은 비율로 식이섬유를 함유하고 있어, 일반적으로 영양학적으로는 전곡 형태로의 섭취가 추천되고 있지만, 조직감과 소화율을 고려하여 발효물 형태의 소비가 바람직한 것으로 판단되고 있다. 본 연구는 효소당화 후, 효모 및 유산균 발효를 거쳐 조제한 보리발효물로부터 조다당 BF-CP를 분리하고, 대식세포에 대한 면역증강 효과 및 세포 내 신호전달을 규명하여 기능성 소재로의 이용방안을 모색하기 위해 계획되었다. BF-CP 획분의 일반화학적 특성을 분석한 결과 70.7% 글루코스 11.4% 자일로스 및 9.0% 아라비노스를 포함하여 91.1%의 중성당으로 이루어진 중성다당이었다. BF-CP는 RAW 264.7 대식세포주에서 농도의존적으로 IL-6, $TNF-{\alpha}$와 같은 사이토카인 및 NO의 생산능을 유도하는 등 높은 대식세포 활성능을 나타냈다. 또한 qPCR 분석을 통해, BF-CP 획분을 대식세포주에 처리하였을 때, 처리 농도에 비례하여 IL-6, $TNF-{\alpha}$ 및 iNOS의 mRNA 유전자 발현을 증가시킴을 확인할 수 있었다. 한편 Western blot을 활용한 신호전달 단백질 추적실험에서 BF-CP 획분을 대식세포주에 처리하였을 때, JNK, ERK 및 p38과 같은 MAPK 경로와 $NF-{\kappa}B$ 경로의 관련 단백질을 인산화시킴이 확인되었으며 그 활성은 BF-CP 농도에 의존적이었다. 이상의 결과로부터 보리발효물 유래 다당 BF-CP는 MAPK와 $NF-{\kappa}B$ 경로를 통해 대식세포를 활성화시키며, 이를 통하여 NO, IL-6 및 $TNF-{\alpha}$와 같은 면역활성화 관련 물질의 생산을 높은 비율로 유도시킨다는 것을 최종 확인할 수 있었다.