• International Journal of Oral Biology
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• 제38권3호
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• pp.121-126
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• 2013

Tumor necrosis factor alpha ($TNF{\alpha}$) is a multifunctional inflammatory cytokine that regulates various cellular and biological processes. Increased levels of $TNF{\alpha}$ have been implicated in a number of human diseases including diabetes and arthritis. Sympathetic nervous system stimulation via the beta2-adrenergic receptor (${\beta}2AR$) in osteoblasts suppresses osteogenic activity. We previously reported that $TNF{\alpha}$ upregulates ${\beta}2AR$ expression in murine osteoblastic cells and that this modulation is associated with $TNF{\alpha}$ inhibition of osteoblast differentiation. In our present study, we explored whether $TNF{\alpha}$ induces ${\beta}2AR$ expression in human osteoblasts and then identified the downstream signaling pathway. Our results indicated that ${\beta}2AR$ expression was increased in Saos-2 and C2C12 cells by $TNF{\alpha}$ treatment, and that this increase was blocked by the inhibition of NF-${\kappa}B$ activation. Chromatin immunoprecipitation and luciferase reporter assay results indicated that NF-${\kappa}B$ directly binds to its cognate elements on the ${\beta}2AR$ promoter and thereby stimulates ${\beta}2AR$ expression. These findings suggest that the activation of $TNF{\alpha}$ signaling in osteoblastic cells leads to an upregulation of ${\beta}2AR$ and also that $TNF{\alpha}$ induces ${\beta}2AR$ expression in an NF-${\kappa}B$-dependent manner.

• BMB Reports
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• 제50권2호
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• pp.97-102
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• 2017

Patients with inflammatory bone disease or cancer exhibit an increased risk of fractures and delayed bone healing. The S100A4 protein is a member of the calcium-binding S100 protein family, which is abundantly expressed in inflammatory diseases and cancers. We investigated the effects of extracellular S100A4 on osteoblasts, which are cells responsible for bone formation. Treating primary calvarial osteoblasts with recombinant S100A4 resulted in matrix mineralization reductions. The expression of osteoblast marker genes including osteocalcin and osterix was also suppressed. Interestingly, S100A4 stimulated the nuclear factor-kappaB (NF-${\kappa}B$) signaling pathway in osteoblasts. More importantly, the ex vivo organ culture of mouse calvariae with recombinant S100A4 decreased the expression levels of osteocalcin, supporting the results of our in vitro experiments. This suggests that extracellular S100A4 is important for the regulation of bone formation by activating the NF-${\kappa}B$ signaling pathway in osteoblasts.

• Asian Pacific Journal of Cancer Prevention
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• 제17권3호
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• pp.1553-1564
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• 2016

Identification of novel therapeutics in glioblastoma remains crucial due to the devastating and infiltrative capacity of this malignancy. The current study was aimed to appraise effect of arsenic trioxide (ATO) in U87MG cells. The results demonstrated that ATO induced apoptosis and impeded proliferation of U87MG cells in a dose-dependent manner and also inhibited classical NF-${\kappa}B$ signaling pathway. ATO further upregulated expression of Bax as an important proapoptotic target of NF-${\kappa}B$ and also inhibited mRNA expression of survivin, c-Myc and hTERT and suppressed telomerase activity. Moreover, ATO significantly increased adhesion of U87MG cells and also diminished transcription of NF-${\kappa}B$ down-stream targets involved in cell migration and invasion, including cathepsin B, uPA, MMP-2, MMP-9 and MMP-14 and suppressed proteolytic activity of cathepsin B, MMP-2 and MMP-9, demonstrating a possible mechanism of ATO effect on a well-known signaling in glioblastoma dissemination. Taken together, here we suggest that ATO inhibits survival and invasion of U87MG cells possibly through NF-${\kappa}B$-mediated inhibition of survivin and telomerase activity and NF-${\kappa}B$-dependent suppression of cathepsin B, MMP-2 and MMP-9.

• Asian Pacific Journal of Cancer Prevention
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• 제13권4호
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• pp.1657-1662
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• 2012

Fucosyltransferase IV (FUT4) has been implicated in cell adhesion, motility, and tumor progression in human epidermoid carcinoma A431 cells. We previously reported that it promotes cell proliferation through the ERK/MAPK and PI3K/Akt signaling pathways; however, the molecular mechanisms underlying FUT4-induced cell invasion remain unknown. In this study we determined the effect of FUT4 on expression of matrix metalloproteinase (MMP)-12 induced by EGF in A431 cells. Treatment with EGF resulted in an alteration of cell morphology and induced an increase in the expression of MMP-12. EGF induced nuclear translocation of nuclear factor kB (NF-${\kappa}B$) and resulted in phosphorylation of $IkB{\alpha}$ in a time-dependent manner. In addition, ERK1/2 and p38 MAPK were shown to play a crucial role in mediating EGF-induced NF-${\kappa}B$ translocation and phosphorylation of $I{\kappa}B{\alpha}$ when treated with the MAPK inhibitors, PD98059 and SB203580, which resulted in increased MMP-12 expression. Importantly, we showed that FUT4 up-regulated EGF-induced MMP-12 expression by promoting the phosphorylation of ERK1/2 and p38 MAPK, thereby inducing phosphorylation/degradation of $I{\kappa}B{\alpha}$, NF-${\kappa}B$ activation. Base on our data, we propose that FUT4 up-regulates expression of MMP-12 via a MAPK-NF-${\kappa}B$-dependent mechanism.

• 한국식품과학회지
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• 제38권6호
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• pp.829-834
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• 2006

HIV 감염 후 AIDS로의 진행과정에서 cytokines의 변화는 필수적인 결과로서 나타나게 된다. 본 연구에서는 AIDS 동물모델을 사용하여 Pyc Cytokines발현에 미치는 영향과 조절 매개체로서 $NF-{\kappa}B$의 관련성 및 작용 기작 확인에 초점을 두었다. LP-BM5 retrovirus에 감염된 C57BL/6 생쥐를 이용하여12주간에 걸친 실험에서Pyc 투여는 Th1과 Th2 cytokines의 혈중농도를 조절하여 murine AIDS로의 진행을 억제하는 데 역할을 하는 것으로 사료된다. 특히 Th2 cytokines의 mRNA 발현을 억제함에 따라 Th1 cytokines의 혈중농도는 상대적으로 증가한 것으로 사료된다. 이러한 결과는 Pyc가 Th2 cytokines을 선택적으로 transcription level에서 조절하고 있음을 의미하고 있다. 또한 Th2 cytokines mRNA 발현 조절은 $NF-{\kappa}B$의 활성화에 의한 것으로 추정된다. 본 연구는 AIDS 동물모델에서 $NF-{\kappa}B$의 조절을 통한 cytokines의 발현 조절의 가능성을 제시함과 동시에 Pyc의 역할에 대해 자료를 제시하고 있다. 또한 향후 murine AIDS 진행 억제제로서의 Pyc의 기작에 대한 일면을 보인 것에 의의를 두고자 한다.

• The Korean Journal of Physiology and Pharmacology
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• 제25권3호
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• pp.217-225
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• 2021

Neuropathic pain (NP) that contributes to the comorbidity between pain and depression is a clinical dilemma. Neuroinflammatory responses are known to have potentially important roles in the initiation of NP and depressive mood. In this study, we aimed to investigate the effects of paeoniflorin (PF) on NP-induced depression-like behaviors by targeting the hippocampal neuroinflammation through the toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB) signaling pathway. We used a murine model of NP caused by unilateral sciatic nerve cuffing (Cuff). PF was injected intraperitoneally once a day for a total of 14 days. Pain and depression-like behavior changes were evaluated via behavioral tests. Pathological changes in the hippocampus of mice were observed by H&E staining. The levels of proinflammatory cytokines in the hippocampus were detected using ELISA. Activated microglia were measured by immunohistochemical staining. The TLR4/NF-κB signaling pathway-associated protein expression in the hippocampus was detected by western blotting. We found that the PF could significantly alleviate Cuff-induced hyperalgesia and depressive behaviors, lessen the pathological damage to the hippocampal cell, reduce proinflammatory cytokines levels, and inhibit microglial over-activation. Furthermore, PF downregulated the expression levels of TLR4/NF-κB signaling pathway-related proteins in the hippocampus. These results indicate that PF is an effective drug for improving the comorbidity between NP and depression.

• 약학회지
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• 제58권1호
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• pp.1-6
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• 2014

We examined whether silibinin and resveratrol affect airway mucin production, degradation of $I{\kappa}B$ and translocation of NF-${\kappa}B$ p65 induced by TNF-${\alpha}$ in NCI-H292 cells. Cells were pretreated with each agent for 30 min and then stimulated with TNF-${\alpha}$ for 24 h or the indicated periods. The two compounds suppressed TNF-${\alpha}$-induced airway mucin production, degradation of $I{\kappa}B$ and translocation of NF-${\kappa}B$ p65. This result suggests that silibinin and resveratrol can regulate the production of mucin induced by TNF-${\alpha}$ through the inactivation of NF-${\kappa}B$ pathway in airway epithelial cells.

• Journal of Acupuncture Research
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• 제22권2호
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• pp.133-139
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• 2005

Cobrotoxin, a venom of Vipera lebetina turanica, is a group of basic peptidescomposed of 233 amino acids with six disulfide bonds formed by twelve cysteins. NF-kB is activated by subsequent release of inhibitory IkB and translocation of p50. Since sulfhydryl group is present in kinase domain of p50 subunit of NF-kB, cobrotoxin could modify NF-kB activity by protein-protein interaction. We therefore examined effect of cobrotoxin on NF-kB activities in lipopolysaccharide (LPS) and sodium nitroprusside (SNP)-stimulated Raw 264.7 mouse macrophages. Cobrotoxin suppressed the LPS and SNP-induced release of IkB and p50 translocation resulted in inhibition of DNA binding activity of NF-kB. Inhibition of NF-kB resulted in reduction of the LPS and SNP-induced production of inflammatory mediators NO and PGE2 generation. The inhibitory effect of cobrotoxin on the NF-kB activity were blocked by addition of reducing agents dithiothreitol and glutathione. These results demonstrate that cobrotoxin inhibits activation of NF-kB, and suggest that pico to nanomolar range of cobrotoxin could inhibit the expression of genes in the NF-kB signal pathway.

• The Korean Journal of Physiology and Pharmacology
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• 제5권1호
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• pp.55-63
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• 2001

In macrophages, lipopolysaccharide (LPS) alone or in combination with $interferon-{\gamma}\;(IFN-{\gamma})$ has been shown to release a nitric oxide (NO) through the increase of the transcription of the inducible nitric oxide synthase (iNOS) gene. To investigate the exact intracellular signaling pathway of the regulation of iNOS gene transcription by LPS plus $IFN-{\gamma},$ the effects of protein tyrosine kinase (PTK) inhibitor and protein kinase C (PKC) inhibitors on NO production, iNOS mRNA expression, nuclear $factor-_{\kappa}B\;(NF-_{\kappa}B)$ binding activity and the promoter activity of iNOS gene containing two $NF-_{\kappa}B$ sites have been examined in a mouse macrophage RAW 264.7 cells. LPS or $IFN-{\gamma}$ stimulated NO production, and their effect was enhanced synergistically by mixture of LPS and $IFN-{\gamma}.$ The PTK inhibitor such as tyrphostin reduced LPS plus $IFN-{\gamma}-induced$ NO production, iNOS mRNA expression and $NF-_{\kappa}B$ binding activity. In contrast, PKC inhibitors such as H-7, Ro-318220 and staurosporine did not show any effect on them. In addition, transfection of RAW 264.7 cells with iNOS promoter linked to a CAT reporter gene revealed that tyrphostin inhibited the iNOS promoter activity through the $NF-_{\kappa}B$ binding site, whereas PKC inhibitors did not. Taken together, these suggest that PTK, but not PKC pathway, is involved in the regulation of the iNOS gene transcription through the $NF-_{\kappa}B$ sites of iNOS promoter in RAW 264.7 macrophages by LPS plus $IFN-{\gamma}$.

• Journal of Veterinary Science
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• 제21권3호
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• pp.50.1-50.16
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• 2020

Background: Porcine parvovirus (PPV) is a single-stranded DNA virus that causes porcine reproductive failure. It is of critical importance to study PPV pathogenesis for the prevention and control of the disease. NS1, a PPV non-structural protein, is participated in viral DNA replication, transcriptional regulation, and cytotoxicity. Our previous research showed that PPV can activate nuclear factor kappa B (NF-κB) signaling pathway and then up-regulate the expression of interleukin (IL)-6. Objectives: Herein, the purpose of this study is to determine whether the non-structural protein NS1 of PPV also has the same function. Methods: Real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR), enzyme-linked immunosorbent assay, western blot, immunofluorescence assay and small interfering RNA (siRNA) were used. Results: Our findings demonstrated that PPV NS1 protein can up-regulate the expression levels of IL-6 and tumor necrosis factor-alpha in a dose-dependent manner. Moreover, PPV NS1 protein was found to induce the phosphorylation of IκBα, then leading to the phosphorylation and nuclear translocation of NF-κB. In addition, the NS1 protein activated the upstream pathways of NF-κB. Meanwhile, TLR2-siRNA assay showed TLR2 plays an important role in the activation of NF-κB signaling pathway induced by PPV-NS1. Conclusions: These findings indicated that PPV NS1 protein induced the up-regulated of IL-6 expression through activating the TLR2 and NF-κB signaling pathways. In conclusion, these findings provide a new avenue to study the innate immune mechanism of PPV infection.