• BMB Reports
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• 제35권4호
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• pp.371-376
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• 2002

The receptor activator of nuclear factor kappa B (RANK) is a member of the tumor necrosis factor (TNF) receptor superfamily. It plays a critical role in osteoclast differentiaion, lymph node organogenesis, and mammary gland development. The stimulation of RANK causes the activation of transcription factors NF-${\kappa}B$ and activator protein 1 (AP1), and the mitogen activated protein kinase (MAPK) c-Jun N-terminal kinase (JNK). In the signal transduction of RANK, the recruitment of the adaptor molecules, TNF receptor-associated factors (TRAFs), is and initial cytoplasmic event. Recently, the association of the MAPK kinase kinase, transforming growth factor-$\beta$-activated kinase 1 (TAK1), with TRAF6 was shown to mediate the IL-1 signaling to NF-${\kappa}B$ and JNK. We investigated whether or not TAK1 plays a role in RANK signaling. A dominant-negative form of TAK1 was discovered to abolish the RANK-induced activation of AP1 and JNK. The AP1 activation by TRAF2, TRAF5, and TRAF6 was also greatly suppressed by the dominant-negative TAK1. the inhibitory effect of the TAK1 mutant on RANK-and TRAF-induced NF-${\kappa}B$ activation was also observed, but less efficiently. Our findings indicate that TAK1 is involved in the MAPK cascade and NF-${\kappa}B$ pathway that is activated by RANK.

• 동의생리병리학회지
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• 제23권1호
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• pp.206-213
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• 2009

본 연구는 RBL-2H3 세포에서 고삼의 NF-${\kappa}B$ (p65) 활성 억제를 통한 과립감소와 전염증성 시토카인 억제 효과에 관한 것으로 주요 내용은 다음과 같다. 본 연구에서는 PMA와 A23187로 유발된 흰쥐 백혈병(RBL-2H3) 세포에서 고삼의 항알레르기 효과에 대하여 알아보았다. 고삼은 투여량에 따라 $\beta$-hexosaminidase의 방출과 TNF-$\alpha$, IL-4, COX-2 등의 생성과 발현을 억제하였다. 실험결과 고삼은 $NF-{\kappa}B$ (p65)의 조절을 통하여 항알레르기 효과를 나타내었는데 이는 $I{\kappa}B-{\alpha}$ 저해의 억제와 항염증 시토카인 발현 억제와도 관계가 있다는 내용이다.

• The Korean Journal of Physiology and Pharmacology
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• 제19권5호
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• pp.441-449
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• 2015

Flavonoids are plant pigments that have been demonstrated to exert various pharmacological effects including anti-cancer, anti-diabetic, anti-atherosclerotic, anti-bacterial, and anti-inflammatory activities. However, the molecular mechanisms in terms of exact target proteins of flavonoids are not fully elucidated yet. In this study, we aimed to evaluate the anti-inflammatory mechanism of scutellarein (SCT), a flavonoid isolated from Erigeron breviscapus, Clerodendrum phlomidis and Oroxylum indicum Vent that have been traditionally used to treat various inflammatory diseases in China and Brazil. For this purpose, a nitric oxide (NO) assay, polymerase chain reaction (PCR), nuclear fractionation, immunoblot analysis, a kinase assay, and an overexpression strategy were employed. Scutellarein significantly inhibited NO production in a dose-dependent manner and reduced the mRNA expression levels of inducible NO synthase (iNOS) and tumor necrosis factor (TNF)-${\alpha}$ in lipopolysaccharide (LPS)-activated RAW264.7 cells. In addition, SCT also dampened nuclear factor (NF)-${\kappa}B$-driven expression of a luciferase reporter gene upon transfection of a TIR-domain-containing adapter-inducing interferon-${\beta}$ (TRIF) construct into Human embryonic kidney 293 (HEK 293) cells; similarly, NF-${\kappa}B$ nuclear translocation was inhibited by SCT. Moreover, the phosphorylation levels of various upstream signaling enzymes involved in NF-${\kappa}B$ activation were decreased by SCT treatment in LPS-treated RAW264.7 cells. Finally, SCT strongly inhibited Src kinase activity and also inhibited the autophosphorylation of overexpressed Src. Therefore, our data suggest that SCT can block the inflammatory response by directly inhibiting Src kinase activity linked to NF-${\kappa}B$ activation.

• 생명과학회지
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• 제29권4호
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• pp.436-441
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• 2019

연은 아시아 국가에서 음식과 약재로 널리 사용되는 재료이다. 본 연구에서는 연의 잎(leaf, NL), 자육(seed, NS), 자방(seedpod, NSP)으로부터 에탄올 추출물을 제조하고 이들의 항염증 활성과 작용기전을 규명하였다. 이들의 항염증 활성을 연구하기 위하여 LPS로 자극된 RAW 264.7 세포에서 nitric oxide (NO) 생산을 측정하였다. NL, NS, NSP는 세포 생존율에 영향을 주지 않으면서, 농도의존적으로 NO의 생산을 현저하게 저해하였으며, iNOS 및 COX-2와 같은 pro-inflammatory 중재자들의 단백질 발현을 감소시켰다. 또한, NL, NS, NSP는 MAPKs 단백질의 인신화를 감소시키고 $NF-{\kappa}B$ p65의 핵으로의 이동을 저해함으로써, 세 추출물에 의한 항염증 활성은 MAPKs 경로와 $NF-{\kappa}B$ 경로를 조절함으로써 이루어짐을 제시한다. 게다가, ROS의 생성이 세 추출물에 의해서 모두 저해되었으며, HO-1의 발현과 HO-1의 전사조절인자인 Nrf2의 핵으로의 이동이 증가되었다. 결론적으로, 이러한 연구 결과는 연의 다양한 부위의 추출물인 NL, NS 그리고 NSP는 항염증 활성을 가지고 있으며, MAPKs, $NF-{\kappa}B$, Nrf2/HO-1 등 다양한 신호경로를 통해 조절할 수 있음을 제시한다.

• 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.

• IMMUNE NETWORK
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• 제3권4호
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• pp.310-319
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• 2003

Inflammatory mediators has been recognized as an important role in the pathogenesis of rheumatoid arthritis (RA). IL-17 is increasingly recognized as an important regulator of immune and inflammatory responses, including induction of proinflammatory cytokines and osteoclastic bone resorption. Evidence of the expression and proinflammatory activity of IL-17 has been demonstrated in RA synovium and in animal models of RA. However, the signaling pathways that regulate IL-17 production remain unknown. In the present study, we investigated the role of the phosphatidylinositol 3 kinase (PI3K)-Akt pathway in the regulation of IL-17 production in RA. PBMC were separated from RA (n=24) patients, and stimulated with various agents (anti CD3, anti CD28, PHA, ConA, IL-15). IL-17 levels were determined by sandwich ELISA and RT-PCR. The production of IL-17 was significantly increased in cells treated with anti-CD3 antibody, PHA, IL-15 or MCP-1 (P<0.05). ConA also strongly induced IL-17 production (P<0.001), whereas TNF-alpha, IL-1beta, IL-18 or TGF-beta did not. IL-17 was detected in the PBMC of patients with osteoarthritis (OA) but their expression levels were much lower than those of RA PBMC. Anti-CD3 antibody activated the PI3K-Akt pathway and activation of the PI3K-Akt pathway resulted in a pronounced augmentation of nuclear factor kappaB ($NF-{\kappa}B$). IL-17 production by activated PBMC in RA is completely or partially blocked in the presence of $NF-{\kappa}B$ inhibitor PDTC and PI3K-Akt inhibitor, wortmannin and LY294002, respectively. Whereas the inhibition of AP-1 and extracellular signal-regulated kinase (ERK)1/2 did not affect IL-17 production. These results provide new insight into that PI3K/Akt and $NF-{\kappa}B$ dependent signal transduction pathway could be involved in the overproduction of key inflammatory cytokine, IL-17 in rheumatoid arthritis.

• 동의생리병리학회지
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• 제26권3호
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• pp.344-350
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• 2012

Previously, we showed that Dangguisoo-san (DGSS), an herbal formula that has been traditionally used for the treatment of blood stagnation, is also applicable for inflammatory lung diseases. Activation of Nrf2, an anti-inflammatory transcription factor, and suppression of NF-${\kappa}B$, a pro-inflammatory transcription factor, were suggested as an underlying mechanism. However, the constituents responsible for these activities remain unidentified. To this end, we prepared the water extracts of the 9 constituents of DGSS and tested for their effect on Nrf2 by using an Nrf2-Luciferase reporter cell line and western blot analysis. Results show that Carthamus tinctorius L.(CT), one of the 9 constituents of DGSS, strongly activated Nrf2. Similarly, when measured the effect of the 9 constituents on NF-${\kappa}B$ by using an NF-${\kappa}B$-Luciferase reporter cell line and western blotting for nuclear p65, indicative of activated NF-${\kappa}B$, most constituents were capable of suppressing NF-${\kappa}B$ in various degrees. However, CT and Cyperus rotundus L. (CR) strongly suppressed NF-${\kappa}B$ activity elicited by LPS. Of note, CT activated Nrf2 and suppressed NF-${\kappa}B$ strongly as well. Our results contributes to corroborating the anti-inflammatory effects of DGSS by identifying CT and CR as two major herbs responsible for activating Nrf2 and suppressing NF-${\kappa}B$. These results suggest that CT and CR represent some of the effects of DGSS in the regulation of inflammation.

• BMB Reports
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• 제42권11호
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• pp.758-763
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• 2009

Cancer-associated antigen (CAGE) induces the expression of matrix metalloproteinase-2 (MMP-2) by activating Akt, which in turn interacts with inhibitory kappa kinase $\beta$ ($I{\kappa}K{\beta}$) to activate nuclear factor ${\kappa}B$ (NF-${\kappa}B$). Akt and p38 mitogen activated protein kinase (p38 MAPK) are necessary for CAGE-mediated induction of the AP-1 subunit JunB, whereas extracellular regulated kinase (ERK) is necessary for the induction of fos-related antigen-1 (Fra-1). Induction of MMP-2 by CAGE requires activator of protein-1 (AP-1) to be bound. Specific binding of JunB to MMP-2 promoter sequences was shown by chromatin immunoprecipitation (ChIP) analysis.

• 대한한의학방제학회지
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• 제27권1호
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• pp.7-16
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• 2019

Objectives : Hemistepta lyrata Bunge (Bunge) has been used for treating wound, hemorrhage, fever in Korean traditional medicine. Present study investigated anti-inflammatory effect of H. lyrata chloroform extract (HLE) and its molecular mechanism involved. Methods : To assess anti-inflammatory effect of HLE, production of nitric oxide (NO) and expressions of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and pro-inflammatory cytokines were measured on lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Moreover, nuclear factor-${\kappa}B$ (NF-${\kappa}B$) signaling pathway was examined to elucidate its molecular mechanism. Results : Pretreatment of HLE inhibited NO production in a concentration dependent manner. HLE also decreased expression of iNOS and COX-2, and alleviated expressions of pro-inflammatory cytokines in LPS-stimulated RAW 264.7 cells. Moreover, HLE pretreatment inhibited phosphorylation of inhibitory-${\kappa}B{\alpha}$ and p65. Conclusions : These results suggest that HLE exhibits anti-inflammatory effect via inhibition of NF-${\kappa}B$.

• 한국식생활문화학회지
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• 제33권4호
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• pp.337-344
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• 2018

Germinated brown rice (GBR, Orysa sartiva L.) has been reported to have anti-obesity and anti-inflammatory effects. However, the mechanisms underlying these effects in adipocytes are not fully understood. Therefore, this study was conducted to explore the anti-inflammatory mechanisms of GBR on lipopolysaccharide (LPS)-stimulated 3T3-L1 adipocytes. 3T3-L1 adipocytes were pretreated with GBR extracts (0-20 mg/mL) 1 h before LPS stimulation. The mRNA expression of adipokines and Toll-like receptor 4 (TLR4) were measured by RT-PCR. The protein expressions of TLR4-related molecules were detected by western blotting and nuclear factor-${\kappa}B$ ($NF-{\kappa}B$) activation was measured. Our results showed that GBR extract dose-dependently inhibited mRNA expression of LPS-induced tumor necrosis factor-${\alpha}$ ($TNF-{\alpha}$), interleukin-6 (IL-6), and monocyte chemoattractant protein-1 (MCP-1). GBR extract was found to inhibit LPS-induced mRNA expression of TLR4 and protein expression of both myeloid differentiation factor 88 (MyD88) and TNF receptor-associated factor 6 (TRAF6). Furthermore, GBR extract significantly inhibited extracellular receptor-activated kinase (ERK) phosphorylation and $NF-{\kappa}B$ activation. These results suggest that GBR extract has the anti-inflammatory effects on LPS-induced inflammation via inhibition of TLR4 signaling, includingthe ERK and $NF-{\kappa}B$ signaling pathways, in adipocytes.