• 제목/요약/키워드: EMSA

검색결과 94건 처리시간 0.032초

Scrophularia Buergeriana inhibits the Production of NO through the Suppression of NF-kB adivity in LPS-stimulated Mouse Peritoneal Macrophages

  • Ha Mi Suk;Kim Young Hee;Ko Woo Shin;Kim Han Do
    • 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.

류마토이드 관절염 환자 골막세포에 대한 계혈등의 면역반응 (Immunity Responses of the Spatholubus Suberectus Dunn to the Synovial Cells Isolated from Patients with Rheumatoid Arthritis)

  • 서해경;오민석;김동희
    • 동의생리병리학회지
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    • 제17권3호
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    • pp.780-786
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    • 2003
  • This study was carried out to know the immunity responses of the Spatholubus suberectus Dunn(hereinafter referred to STSD) to the synovial cells isolated from patients with rheumatoid arthritis. Various experiments were performed in vitro to analyse the immunity effects of STSD. Gene expression and production of pro-inflammatory cytokines such as IL-1β, IL-6, TNF-α, iNOS and COX-2 were determined by RT-PCR and ELISA kit. And also the binding activity of NF-kB and AP-1 were measured by Electromobility shift assay (EMSA) and the production of ROS was measured by flow cytometry. The results were obtained as follows 1. The gene expression and production of pro-inflammatory cytokines IL-1β, IL-6, TNF-α were reduced significantly. 2. The gene expression of iNOS and COX-2 were reduced. 3. The binding activity of NF-kB and AP-1 were inhibited. 4. The production of ROS in human synovial cells was reduced significantly. Comparison of the results for this study showed that STSD had immunomodulatory effects of suppressing or enhancing. So we expect that STSD should be used as a effective drugs for not only rheumatoid arthritis but also another auto-immune disease. Therefore we have to survey continuously in looking for the effective substance and mechanism in the future.

Effects of Takrisodokyeum Water Extracts on LNCaP Prostate Cancer Cells

  • Park, Kwan-Woo;Kim, Song-Baeg;Choi, Chang-Min;Ryu, Do-Gon;Kwon, Kang-Beom
    • 동의생리병리학회지
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    • 제23권5호
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    • pp.1154-1160
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    • 2009
  • Androgen receptors (AR) play a crucial role in the development and progression of prostate cancer. Many studies have suggested that prostate cancer cell proliferation is inhibited by AR downregulation, and it has been reported that Takrisodokyeum (TRSDY) induced apoptotic cell death and suppressed tumorigenesis in human leukemia cells. Therefore, this study was conducted to elucidate the mechanism by which TRSDY affects cell growth and AR expression in androgen-dependent prostate cancer cells (LNCaP cells). We investigated the proliferation and apoptosis of LNCaP cells using MTT and DNA fragmentation assays. In addition, we used western blot analysis to assess the effects of TRSDY on the expression of the AR target gene, prostate-specific antigen (PSA). Furthermore, the mechanism of AR downregulation by TRSDY was investigated using EMSA to analyze the binding activity of AR to androgen response elements (ARE). TRSDY significantly suppressed proliferation and induced apoptosis in LNCaP cells. In addition, TRSDY-induced apoptotic cell death was accompanied by activation of caspase-3 and cleavage of its substrate, poly(ADP-ribose) polymerase. TRSDY also inhibited the constitutively expressed- or 5a-dihydrotestosterone (DHT)-induced AR/PSA protein levels. However, these effects were mediated by inhibition of the binding of AR to ARE. TRSDY-mediated AR/PSA downregulation contributes to the inhibition of cell proliferation and the induction of apoptosis in LNCaP human prostate cancer cells. Our findings suggest that TRSDY may be used as a chemopreventive or chemotherapeutic agent for the treatment of prostate cancer.

Inulin stimulates NO synthesis via activation of PKC-$\alpha$ and protein tyrosine kinase, resulting in the activation of NF-$textsc{k}$B by IFN-ν-primed RAW 264.7 cells

  • Koo, Hyun-Na;Hong, Seung-Heon;Kim, Hyung-Min
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 2003년도 Annual Meeting of KSAP : International Symposium on Pharmaceutical and Biomedical Sciences on Obesity
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    • pp.78-78
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    • 2003
  • Inulin, an active component of Chicorium intybus root, has been shown to stimulate the growth of bifidobacteria, and inhibit colon carcinogenesis. NO mediates a number of the host-defense functions of activated macrophages, including antimicrobial and tumoricidal activity. We examined the effect of inulin on the synthesis of NO in RAW 264.7 cells. Inulin alone had no effect, whereas inulin with IFN-ν synergistically increased the NO production and inducible NO synthase (iNOS) expression in RAW 264.7 cells. Synergy between IFN-ν and inulin was mainly dependent on inulin-induced TNF-${\alpha}$ secretion. Also, protein kinase C (PKC)-${\alpha}$ was involved in the inulin-induced NO production. Inulin-mediated NO production was inhibited by the protein tyrosine kinase (PTK) inhibitor, tyrphostin AG126. Since iNOS gene transcriptions have been shown to be under the control of the NF -$\kappa$B/Rel family of transcription factors, we assessed the effect of inulin on NF -$\kappa$B/Rel using an EMSA. Inulin produced strong induction of NF-$\kappa$B/Rel binding, whereas AP-l binding was slightly induced in RAW 264.7 cells. Inulin stimulated phosphorylation and degradation of I$\kappa$B-${\alpha}$. These results suggest that in IFN-ν-primed RAW 264.7 cells inulin might stimulate NO synthesis via activation of PKC-${\alpha}$ and PTK, resulting in the activation of NF-$\kappa$B.

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Epigenetic and Glucocorticoid Receptor-Mediated Regulation of Glutathione Peroxidase 3 in Lung Cancer Cells

  • An, Byung Chull;Jung, Nak-Kyun;Park, Chun Young;Oh, In-Jae;Choi, Yoo-Duk;Park, Jae-Il;Lee, Seung-won
    • Molecules and Cells
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    • 제39권8호
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    • pp.631-638
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    • 2016
  • Glutathione peroxidase 3 (GPx3), an antioxidant enzyme, acts as a modulator of redox signaling, has immunomodulatory function, and catalyzes the detoxification of reactive oxygen species (ROS). GPx3 has been identified as a tumor suppressor in many cancers. Although hyper-methylation of the GPx3 promoter has been shown to down-regulate its expression, other mechanisms by which GPx3 expression is regulated have not been reported. The aim of this study was to further elucidate the mechanisms of GPx3 regulation. GPx3 gene analysis predicted the presence of ten glucocorticoid response elements (GREs) on the GPx3 gene. This result prompted us to investigate whether GPx3 expression is regulated by the glucocorticoid receptor (GR), which is implicated in tumor response to chemotherapy. The corticosteroid dexamethasone (Dex) was used to examine the possible relationship between GR and GPx3 expression. Dex significantly induced GPx3 expression in H1299, H1650, and H1975 cell lines, which exhibit low levels of GPx3 expression under normal conditions. The results of EMSA and ChIP-PCR suggest that GR binds directly to GRE 6 and 7, both of which are located near the GPx3 promoter. Assessment of GPx3 transcription efficiency using a luciferase reporter system showed that blocking formation of the GR-GRE complexes reduced luciferase activity by 7-8-fold. Suppression of GR expression by siRNA transfection also induced down-regulation of GPx3. These data indicate that GPx3 expression can be regulated independently via epigenetic or GR-mediated mechanisms in lung cancer cells, and suggest that GPx3 could potentiate glucocorticoid (GC)-mediated anti-infla-mmatory signaling in lung cancer cells.

Lonicera Japonioa Inhibits the Production of NO through the Suppression of NF-kB Activity in LPS-stimulated Mouse Peritoneal Macrophages

  • 김영희;김한도
    • 한방안이비인후피부과학회지
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    • 제17권1호
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    • pp.163-171
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    • 2004
  • The flowers of Lonicera japonica Thunb. (Caprifoliaceae) has been used as anti-inflammatory drug in the folk medicine recipe and been proved its anti-inflammatory effect in the oriental medicine. However, the action mechanism of Lonicera japonica that exhibits anti-inflammatory effects has not been determined. Since nitric oxide (NO) is one of the major inflammatory parameter, we studied the effect of aqueous extracts of Lonicera japonica (AELJ) on NO production in lipopolysaccharide (LPS)-stimulated mouse peritoneal macrophages. NO and inducible NO synthase (iNOS) level were significantly reduced in LPS-stimulated macrophages by AELJ compared to those without Electrophoretic mobility shift assay (EMSA) indicated that AELJ blocked the activation of nuclear factor kappa B (NF-kB), which was considered to be a potential transcription factor for the iNOS expression. AELJ also blocked the phosphorylation and degradation of inhibitor of kappa B-alpha (IkB-${\alpha}$). Furthermore, IkB kinase alpha (IKK${\alpha}$), which is known to phosphorylate serine residues of IkB directly, is inhibited by AELJ in vivo and in vitro. These results suggest that AELJ could exert its anti-inflammatory actions by suppressing the synthesis of NO through inhibition of NF-kB activity.

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Melittin이 NF-${\kappa}$B의 불활성화를 통한 DU-145 전립선 암세포의 성장 및 세포자멸사 유도에 미치는 영향 (Melittin Inhibits DU -145 Human Refractory Prostate Cancer Cell Growth Through Induction of Apoptosis Via Inactivation of NF-${\kappa}$B)

  • 최철훈;송호섭
    • Journal of Acupuncture Research
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    • 제26권3호
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    • pp.39-48
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    • 2009
  • 목적 : 이 연구는 봉약침의 주요성분인 멜리틴이 NF-${\kappa}$B의 활성억제를 통하여 세포자멸사를 유도하고, 전립선 암세포주인 DU-145 세포의 성장을 억제하는지를 확인하고 멜리틴의 NF-${\kappa}$B 활성억제기전을 살펴보고자 하였다. 방법 : 멜리틴을 처리한 후 DU-145의 성장억제를 관찰하기 위해 WST-1 assay를 시행하였고, 세포자멸 사의 관찰에는 DAPI stairung assay를 통한 세포형태관찰을 시행하였으며, 염증관련유전자 발현 관찰에는 western blot analysis를 시행하였고, 세포자멸사와 연관된 NF-${\kappa}$B의 활성 변화를 관찰하기 위해 EMSA와 luciferase assay를 시행하였으며, DU-145에서 멜리틴과 NF-${\kappa}$B의 상호작용을 관찰하기 위해 transient transfection assay를 시행 시 세포생존율과 NF-${\kappa}$B의 활성 변동을 측정하였다. 결과 : DU-145 세포에 멜리틴을 처리한 후, 전립선암세포의 성장, 세포자멸사의 유발, 염중관련유전자 발현 및 NF-${\kappa}$B의 활성, NF-${\kappa}$B의 p50 치환 후 NF-${\kappa}$B의 활성과 DU-145 세포 증식에 미치는 영향을 관찰하여 다음과 같은 결과를 얻었다. 1. DU-145 세포에서 멜리틴을 처리한 후 세포자멸사가 유도되어 세포성장이 억제되었다. 2. DU-145 세포에서 멜리틴을 처리한 후 염증관련유전자 발현 및 NF-${\kappa}$B의 활성에 유의한 감소를 나타내었다. 3. DU-145 세포에서 NF-${\kappa}$B의 p50와 IKK들을 치환하여 작용기를 없애고 멜리틴을 처리하였을 경우에도 세포활성 및 NF-${\kappa}$B의 활성의 유의한 감소를 나타내었다.

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Synergistic Effects of Bee Venom and Natural Killer Cells on B16F10 Melanoma Cell Growth Inhibition through IL-4-mediated Apoptosis

  • Sin, Dae Chul;Kang, Mi Suk;Song, Ho Sueb
    • Journal of Acupuncture Research
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    • 제34권1호
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    • pp.1-9
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    • 2017
  • Objectives : We investigated the synergistic effects of bee venom (BV) and natural killer (NK) cells on B16F10 melanoma cell apoptosis mediated by IL-4. Methods : We performed a cell viability assay to determine whether BV can enhance the inhibitory effect of NK-92MI cells on the growth of B16F10 melanoma cells, and western blot analysis to detect changes in the expression of IL-4, $IL-4R{\alpha}$, and other apoptosis-related proteins. EMSA was performed to observe the activity of STAT6. To confirm that the inhibitory effect of BV and NK cells was mediated by IL-4, the above tests were repeated after IL-4 silencing by siRNA (50 nM). Results : B16F10 melanoma cells co-cultured with NK-92MI cells and simultaneously treated by BV ($5{\mu}g/ml$) showed a higher degree of proliferation inhibition than when treated by BV ($5{\mu}g/ml$) alone or co-cultured with NK-92MI cells alone. Expression of IL-4, $IL-4R{\alpha}$, and that of other pro-apoptotic proteins was also enhanced after co-culture with NK-92MI cells and simultaneous treatment with BV ($5{\mu}g/ml$). Furthermore, the expression of anti-apoptotic bcl-2 decreased, and the activity of STAT6, as well as the expression of STAT6 and p-STAT6 were enhanced. IL-4 silencing siRNA (50 nM) in B16F10 cells, the effects of BV treatment and NK-92MI co-culture were reversed. Conclusion : These results suggest that BV could be an effective alternative therapy for malignant melanoma by enhancing the cytotoxic and apoptotic effect of NK cells through an IL-4-mediated pathway.

Cooperative transcriptional activation of ATP-binding cassette sterol transporters ABCG5 and ABCG8 genes by nuclear receptors including Liver-X-Receptor

  • Back, Su Sun;Kim, Jinsu;Choi, Daehyung;Lee, Eui Sup;Choi, Soo Young;Han, Kyuhyung
    • BMB Reports
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    • 제46권6호
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    • pp.322-327
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    • 2013
  • The ATP-binding cassette transporters ABCG5 and ABCG8 form heterodimers that limit absorption of dietary sterols in the intestine and promote cholesterol elimination from the body through hepatobiliary secretion. To identify cis-regulatory elements of the two genes, we have cloned and analyzed twenty-three evolutionary conserved region (ECR) fragments using the CMV-luciferase reporter system in HepG2 cells. Two ECRs were found to be responsive to the Liver-X-Receptor (LXR). Through elaborate deletion studies, regions containing putative LXREs were identified and the binding of $LXR{\alpha}$ was demonstrated by EMSA and ChIP assay. When the LXREs were inserted upstream of the intergenic promoter, synergistic activation by $LXR{\alpha}/RXR{\alpha}$ in combination with GATA4, $HNF4{\alpha}$, and LRH-1, which had been shown to bind to the intergenic region, was observed. In conclusion, we have identified two LXREs in ABCG5/ABCG8 genes for the first time and propose that these LXREs, especially in the ECR20, play major roles in regulating these genes.

Human Cytomegalovirus Inhibition of Interferon Signal Transduction

  • Daniel M. Miller
    • 미생물학회지
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    • 제38권4호
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    • pp.203-203
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    • 2002
  • Cytomegalovirus (CMV), a beta-herpesvirus with worldwide distribution, exhibits host persistence, a distinguishing characteristic of all herpesviruses. This persistence is dependent upon restricted gene expression in infected cells as well as the ability of productively infected cells to escape from normal cell-mediated anti-viral immunosurveillance. Type I (IFN-α/β) and type II (IFN-γ) interferons are major components of the innate defense system against viral infection. They are potent inducers of MHC class I and II antigens and of antigen processing proteins. Additionally, IFNS mediate direct antiviral effects through induction effector molecules that block viral infection and replications such as 2′, 5-oligoadenylate synthetase (2, 5-OAS). IFNS function through activation of well-defined signal transduction pathways that involve phosphorylation of constituent proteins and ultimate formation of active transcription factors. Recent studies have shown that a number of diverse viruses, including CMV, EBV, HPV mumps and Ebola, are capable of inhibiting IFN-mediated signal transduction through a variety of mechanisms. As an example, CMV infection inhibits the ability of infected cells Is transcribe HLA class I and II antigens as well as the antiviral effector molecules 2, 5-OAS and MxA I. EMSA studies have shown that IFN-α and IFN-γ are unable to induce complete signal transduction in the presence of CMV infection, phenomena that are associated with specific decreases in JAKl and p48. Viral inhibition of IFN signal transduction represents a new mechanistic paradigm for increased viral survival, a paradigm predicting widespread consequences in the case of signal transduction factors common to multiple cytokine pathways.