• Title/Summary/Keyword: NF-kB activation

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A Methanol Extract of Adansonia digitata L. Leaves Inhibits Pro-Inflammatory iNOS Possibly via the Inhibition of NF-κB Activation

  • Ayele, Yihunie;Kim, Jung-Ah;Park, Eunhee;Kim, Ye-Jung;Retta, Negussie;Dessie, Gulelat;Rhee, Sang-Ki;Koh, Kwangoh;Nam, Kung-Woo;Kim, Hee Seon
    • Biomolecules & Therapeutics
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    • v.21 no.2
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    • pp.146-152
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    • 2013
  • This study examined the total polyphenol content of eight wild edible plants from Ethiopia and their effect on NO production in Raw264.7 cells. Owing to its relatively high polyphenol concentration and inhibition of NO production, the methanol extract of Adansonia digitata L. leaf (MEAD) was subjected to detailed evaluation of its antioxidant and anti-inflammatory effects. Antioxidant effects were assessed by measuring free-radical-scavenging activity using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and oxygen-radical-absorbance capacity (ORAC) assays, while anti-inflammatory effects were assessed by measuring inducible nitric oxide synthase (iNOS) expression in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. In the ORAC assay, MEAD was 10.2 times more potent than vitamin C at eliminating peroxyl radicals. In DPPH assay, MEAD also showed a strong ROS scavenging effect. MEAD significantly inhibited iNOS activity ($IC_{50}=28.6{\mu}g/ml$) of LPS-stimulated Raw264.7 cells. We also investigated the relationship between iNOS expression and nuclear factor kappa B (NF-${\kappa}B$) activation. MEAD inhibited $I{\kappa}B{\alpha}$ degradation and NF-${\kappa}B$ translocation from the cytosol to the nucleus in LPS-induced RAW264.7 cells without significant cytotoxic effects, as confirmed by MTT assay. These results suggest that MEAD inhibits anti-inflammatory iNOS expression, which might be related to the elimination of peroxyl radicals and thus the inhibition of $I{\kappa}B{\alpha}$-mediated NF-${\kappa}B$ signal transduction.

Inhibitory Effect of NAD(P)H:Quinone Oxidoreductase 1 on the Activation of Macrophages (NQO1 (NAD(P)H:quinone oxidoreductase 1)에 의한 대식세포 활성화 억제)

  • Hong, Ji;Zhang, Peng;Yoon, I Na;Kim, Ho
    • Journal of Life Science
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    • v.27 no.8
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    • pp.873-878
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    • 2017
  • We previously reported that NAD(P)H:quinone oxidoreductase 1 (NQO1)-knockout (KO) mice exhibited spontaneous inflammation in the gut. We also found that NQO1-KO mice showed highly increased inflammatory responses compared with NQO1-WT control mice when subjected to DSS-induced experimental colitis. In a Clostridium difficile toxin-induced mouse enteritis model, NQO1-KO mice were also sensitive compared with NQO1-WT mice. Moreover, numerous studies have shown that NQO1 is functionally associated with immune regulation. Here, we assessed whether NQO1 defects can alter macrophage activation. We found that peritoneal macrophages isolated from NQO1-KO mice produced more IL-6 and $TNF-{\alpha}$ than those isolated from NQO1-WT mice. Moreover, the dicumarol-induced inhibition of NQO1 significantly increased IL-6 and $TNF-{\alpha}$ production in peritoneal macrophages isolated from NQO1-WT mice, as well as in the cultured mouse macrophage cell line, RAW264.7. These results indicate that NQO1 may negatively regulate the activation of macrophages. Knockout or chemical inhibition of NQO1 markedly reduced the expression of $I{\kappa}B$ (inhibitor of $NF{\kappa}B$) in both mouse peritoneal macrophages and RAW264.7 cells. Finally, RAW264.7 cells treated with dicumarol exhibited morphological changes reflecting macrophage activation. Our results suggest that NQO1 may suppress the $NF{\kappa}B$ pathways in macrophages, thereby suppressing the activation of these cells. Thus, immunosuppressive activity may be among the many possible functions of NQO1.

Proinflammatory Cytokine and Nitric Oxide Production by Human Macrophages Stimulated with Trichomonas vaginalis

  • Han, Ik-Hwan;Goo, Sung-Young;Park, Soon-Jung;Hwang, Se-Jin;Kim, Yong-Seok;Yang, Michael Sungwoo;Ahn, Myoung-Hee;Ryu, Jae-Sook
    • Parasites, Hosts and Diseases
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    • v.47 no.3
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    • pp.205-212
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    • 2009
  • Trichomonas vaginalis commonly causes vaginitis and perhaps cervicitis in women and urethritis in men and women. Macrophages are important immune cells in response to T. vaginalis infection. In this study, we investigated whether human macrophages could be involved in inflammation induced by T. vaginalis. Human monocyte-derived macrophages (HMDM) were co-cultured with T. vaginalis. Live, opsonized-live trichomonads, and T. vaginalis Iysates increased proinflammatory cytokines, such as TNF-${\alpha}$, IL-$1{\beta}$, and IL-6 by HMDM. The involvement of nuclear factor (NF)-${\kappa}B$ signaling pathway in cytokine production induced by T. vaginalis was confirmed by phosphorylation and nuclear translocation of p65 NF-${\kappa}B$. In addition, stimulation with live T. vaginalis induced marked augmentation of nitric oxide (NO) production and expression of inducible NO synthase (iNOS) levels in HMDM. However, trichomonad-induced NF-${\kappa}B$ activation and TNF-${\alpha}$ production in macrophages were significantly inhibited by inhibition of iNOS levels with L-NMMA (NO synthase inhibitor). Moreover, pretreatment with NF-${\kappa}B$ inhibitors (PDTC or Bay11-7082) caused human macrophages to produce less TNF-${\alpha}$. These results suggest that T. vaginalis stimulates human macrophages to produce proinflammatory cytokines, such as IL-1, IL-6, and TNF-${\alpha}$, and NO. In particular, we showed that T. vaginalis induced TNF-${\alpha}$ production in macrophages through NO-dependent activation of NF-${\kappa}B$, which might be closely involved in inflammation caused by T. vaginalis.

The Preventive and Curative Effect of Cyanidin-3β-D-Glycoside and Its Metabolite Protocatechuic Acid Against TNBS-induced Colitis in Mice

  • Jang, Se-Eun;Choi, Jong-Ryul;Han, Myung Joo;Kim, Dong-Hyun
    • Natural Product Sciences
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    • v.22 no.4
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    • pp.282-286
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    • 2016
  • Cyanidin-$3{\beta}$-D-glycoside (C3G), which is widely distributed in herbal medicines and functional foods, exhibits anti-inflammatory, anti-oxidant, and anti-scratching behavioral effects. Orally administered C3G is metabolized to protocatechuic acid (PA) by gut microbiota. Therefore, we compared the anti-colitic effect of C3G to that of PA in mice with 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis. Orally administered C3G and PA preventively and curatively ameliorated TNBS-induced colitis parameters, including macroscopic colitis score, colon shortening, and increase of myeloperoxidase activity. Treatment with C3G or PA also inhibited the expression of cyclooxygenase-2, inducible NO synthatase, $IL-1{\beta}$, IL-6, and $TNF-{\alpha}$ and the activation of $NF-{\kappa}B$ in the colon of mice with TNBS-induced colitis. Furthermore, these also inhibited lipopolysaccharide-induced $NF-{\kappa}B$ activation and $TNF-{\alpha}$ expression in peritoneal macrophages. The anti-colitic effect of PA was more effective than C3G. Orally administered PA more potently attenuate colitis than C3G by inhibiting $NF-{\kappa}B$ activation and the anti-colitic efficacy of C3G may be dependent on the biotransformation of C3G to PA by gut microbiota.

Fentanyl Increases Colorectal Carcinoma Cell Apoptosis by Inhibition of NF-κB in a Sirt1-dependent Manner

  • Zhang, Xiu-Lai;Chen, Min-Li;Zhou, Sheng-Li
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.22
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    • pp.10015-10020
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    • 2014
  • Background: Fentanyl is used as an analgesic to treat pain in a variety of patients with cancer and recently it has become considered to also act as an antitumor agent. The study present was designed to investigate the effects of fentanyl on colorectal cancer cell growth and plausible mechanisms. Materials and Methods: The human colorectal carcinoma cell line HCT116 was subcutaneously injected into nude mice. The viability of HCT116 was tested by MTT assay, and apoptosis by flow cytometry and caspase-3 activity. The expression of Sirt1 and NF-${\kappa}B$ were evaluated by Western blotting and the levels of Sirt1 and NF-${\kappa}B$ by fluorescence method. SiRNA was used to silence and Ad-Sirt1 to overexpress Sirt1. Results: Our data showed that fentanyl could inhibit tumor growth, with increased expression of Sirt1 and down-regulation of Ac-p65 in tumors. Compared with control cells without treatment, HCT116 cells that were incubated with fentanyl had a higher apoptotic rate. Moreover, fentanyl could increase expression and activity of Sirt1 and inhibitor expression and activity of NF-${\kappa}B$, which might be mechanisms of fentanyl action. Conclusions: Fentanyl increased colorectal carcinoma cell apoptosis by inhibition of NF-${\kappa}B$ activation in a Sirt1-dependent manner.

Inhibitory Effect of Mori Ramulus on Oxidative Stress Induced by High Glucose in LLC-$PK_1$ Cells (고농도 포도당에 노출된 마우스 신장상피세포에서 상지(桑枝)의 산화 스트레스 억제 효과)

  • Jang, Soo-Young;Shin, Hyeon-Cheol
    • The Journal of Internal Korean Medicine
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    • v.32 no.1
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    • pp.56-67
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    • 2011
  • Objectives : Recent etiological studies show that oxidative stress might play a major role in the diabetes and its complications. Mori Ramulus (MR) has been known to have antioxidative, anti-inflammatory and antidiabetic effects. The methanol extract of MR was tested for its effectiveness in LLC-PK1 cells exposed to high glucose. Methods : The cytoprotective effect of MR was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The antioxidative effect was measured in terms of generation amount of ${\cdot}O_2^-$ by 2',7'-dichlorodihydrofluorescein diacetate (DCFDA), NO by 4,5-diaminofluorescein (DAF-2), $ONOO^-$ by dihydrorhodamine 123 (DHR 123) in the high glucose -treated LLC-$PK_1$ cells. Western blotting was performed using anti-AGE, anti-RAGE, anti-MAPKs(ERK1/2, JNK, p38), anti-PI3K, anti-Akt, and anti-NF-${\kappa}$B (p50, p65) respectively. Results : MR extract reduced cell death and inhibited the generation of ${\cdot}O_2^-$, NO, $ONOO^-$ in the high glucose-treated LLC-$PK_1$ cells. MR inhibited the expression of AGE, RAGE, MAPKs, PI3K, and Akt by means of decreasing NF-${\kappa}$B activation. MR also inhibited NF-${\kappa}$B activation itself. Conclusions : These results indicate MR has cytoprotective, antioxidative, and anti-inflammatory effects. Therefore it is suggested that MR might prevent and cure diabetes and its complications.

The Inactivation of ERK1/2, p38 and NF-kB Is Involved in the Down-Regulation of Osteoclastogenesis and Function by A2B Adenosine Receptor Stimulation

  • Kim, Bo Hyun;Oh, Ju Hee;Lee, Na Kyung
    • Molecules and Cells
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    • v.40 no.10
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    • pp.752-760
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    • 2017
  • A2B adenosine receptor (A2BAR) is known to be the regulator of bone homeostasis, but its regulatory mechanisms in osteoclast formation are less well-defined. Here, we demonstrate the effect of A2BAR stimulation on osteoclast differentiation and activity by RANKL. A2BAR was expressed in bone marrow-derived monocyte/macrophage (BMM) and RANKL increased A2BAR expression during osteoclastogenesis. A2BAR stimulation with its specific agonist BAY 60-6583 was sufficient to inhibit the activation of ERK1/2, p38 MAP kinases and $NF-{\kappa}B$ by RANKL as well as it abrogated cell-cell fusion in the late stage of osteoclast differentiation. Stimulation of A2BAR suppressed the expression of osteoclast marker genes, such as c-Fos, TRAP, Cathepsin-K and NFATc1, induced by RANKL, and transcriptional activity of NFATc1 was also inhibited by stimulation of A2BAR. A2BAR stimulation caused a notable reduction in the expression of Atp6v0d2 and DC-STAMP related to cell-cell fusion of osteoclasts. Especially, a decrease in bone resorption activity through suppression of actin ring formation by A2BAR stimulation was observed. Taken together, these results suggest that A2BAR stimulation inhibits the activation of ERK1/2, p38 and $NF-{\kappa}B$ by RANKL, which suppresses the induction of osteoclast marker genes, thus contributing to the decrease in osteoclast cell-cell fusion and bone resorption activity.

Anti-inflammatory Effect of Fructus Chaenomelis(FC) (목과(木瓜)의 항염(抗炎) 및 면역반응(免疫反應)에 대한 실험적(實驗的) 연구(硏究))

  • Lee, Su-Jeong;Kim, Song-Baeg;Choe, Chang-Min;Lee, Key-Sang;Cho, Han-Baek
    • The Journal of Korean Obstetrics and Gynecology
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    • v.21 no.4
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    • pp.36-48
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    • 2008
  • Purpose: The purpose of this study is to investigate anti-inflammatory effect and immune responses of aqueous extract from Fructus Chaenomelis (FC). Methods: We studied anti-inflammatory effect by means of examining the production of NO(nitric oxide) and expressions of pro-inflammatory cytokine (TNF-$\alpha$(tumor necrosis factor-alpha), IL(Interleukin)-6, IL-12) in the LPS-induced peritoneal macrophages of mice. Also, The western blot analysis has been done to look into the mechanism of anti-inflammatory effect. Results: 1. The FC extract did not have any cytotoxicity in the peritoneal macrophages. 2. The FC extract inhibits the productions of NO, IL-6. IL-12 in the LPS-stimulated peritoneal macrophages of mice, but not of TNF-$\alpha$. 3. The FC extract inhibits the activation of NF-${\kappa}B$(nuclear factor-kappa B) by keeping $I{\kappa}B-\alpha$(inhibitory kappa B-alpha) from degradating, but not of MAPKs(mitogen-activated protein kinases) such as ERK(extracelluar signa 1-regulated kinase), JNK(c-Jun N-terminal kinase), p38. Conclusion: These results show that FC extract inhibits the production of pro-inflammatory cytokines such as IL-6. IL-12. NO by inhibiting NF-${\kappa}B$ activation in the peritoneal macrophages of mice. In conclusion, this experiment suggests that FC extract may be effective for the treatment of acute and chronic inflammation including genitourinary infection.

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