• Biomedical Science Letters
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• v.19 no.1
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• pp.1-8
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• 2013

Parkin is known to be a tumor suppressor protein. Previously, we determined that parkin expression restores susceptibility to TNF-${\alpha}$-induced death of HeLa cells, a human cervical cancer cell line resistant to TNF-${\alpha}$-induced cell death. MMP-3 is a zinc-dependent protease recently reported to activate intracellular apoptotic signaling. In this study we examined the regulation of MMP-3 expression by parkin in TNF-${\alpha}$-treated HeLa cells. Furthermore, we investigated the signaling pathway involved in parkin-induced expression of MMP-3. We found that HeLa cells exhibit low levels of MMP-3 but is induced after introduction of the parkin gene into HeLa cells. Furthermore, MMP-3 expression increased further when parkin expressing cells were treated with TNF-${\alpha}$. Using chemical inhibitors of cell signaling pathways, we found that MEK-1 (PD98059), PI3K (LY294002), p38 MAPK (SB203580), and JNK inhibitors alleviated parkin-induced up-regulation of MMP-3. Finally, we show that TNF-${\alpha}$-induced cell death in parkin expressing cells is inhibited by using a MMP-3 inhibitor. These results suggest that parkin expression induces prolonged expression of MMP-3 via MEK-1, PI3K, MAPK, and JNK pathway in HeLa cells allowing the HeLa cells to become sensitive to TNF-${\alpha}$-induced cell death. These results implicate a role of MMP-3 in parkin-induced cell death in TNF-${\alpha}$ treated HeLa cells.

• Journal of Microbiology and Biotechnology
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• v.14 no.1
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• pp.81-89
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• 2004

Tumor necrosis factor-$\alpha$ (TNF-$\alpha$) and lymphotoxin-$\alpha$ (LT-$\alpha$, TNF-$\beta$) can initiate and perpetuate human diseases such as multiple sclerosis (MS), rheumatoid arthritis (RA), and insulin-dependent diabetes mellitus (IDDM). TNFs can be blocked by the use of soluble TNF receptors. However, since monomeric soluble receptors generally exhibit low affinity or function as agonists, the use of monomeric soluble receptors has been limited in the case of cytokines such as TNF-$\alpha$, TNF-$\alpha$, interleukin (IL)-1, IL-4, IL-6, and IL-13, which have adapted to a multi component receptor system. For these reasons, very high-affinity inhibitors were created for the purpose of a TNFs antagonist to bind the TNFR and trigger cellular signal by using the multistep polymerase chain reaction method. First, recombinant simple TNFR-Ig fusion proteins were constructed from the cDNA sequences encoding the extracellular domain of the human p55 TNFR (CD120a) and the human p75 TNFR (CD120b), which were linked to hinge and constant regions of human $IgG_1$ heavy chain, respectively using complementary primers (CP) encoding the complementary sequences. Then, concatameric TNFR-Ig fusion proteins were constructed using recombinant PCR and a complementary primer base of recombinant simple TNFR-Ig fusion proteins. For high level expression of recombinant fusion proteins, Chinese hamster ovary (CHO) cells were used with a retroviral expression system. The transfected cells produced the simple concatameric TNFR-Ig fusion proteins capable of binding TNF and inactivating it. These soluble versions of simple concantameric TNFR-Ig fusion proteins gave rise to multiple forms such as simple dimers and concatameric homodimers. Simple TNFR-1g fusion proteins were shown to have much more reduced TNF inhibitory activity than concatameric TNFR-Ig fusion proteins. Concatameric TNFR-Ig fusion proteins showed higher affinity than simple TNFR-Ig fusion proteins in a receptor inhibitor binding assay (RIBA). Additionally, concatameric TNFR-Ig fusion proteins were shown to have a progressive effect as a TNF inhibitor compared to the simple TNFR-Ig fusion proteins and conventional TNFR-Fc in cytotoxicity assays, and showed the same results for collagen induced arthritis (CIA) in mice in vivo.

• BMB Reports
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• v.50 no.11
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• pp.584-589
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• 2017

Intercellular adhesion molecule-1 (ICAM-1), which is induced by tumor necrosis factor (TNF)-${\alpha}$, contributes to the entry of immune cells into the site of inflammation in the skin. Here, we show that protein tyrosine phosphatase non-receptor type 21 (PTPN21) negatively regulates ICAM-1 expression in human keratinocytes. PTPN21 expression was transiently induced after stimulation with TNF-${\alpha}$. When overexpressed, PTPN21 inhibited the expression of ICAM-1 in HaCaT cells but PTPN21 C1108S, a phosphatase activity-inactive mutant, failed to inhibit ICAM-1 expression. Nuclear factor-${\kappa}B$ (NF-${\kappa}B$), a key transcription factor of ICAM-1 gene expression, was inhibited by PTPN21, but not by PTPN21 C1108S. PTPN21 directly dephosphorylated phospho-inhibitor of ${\kappa}B$ ($I{\kappa}B$)-kinase ${\beta}$ ($IKK{\beta}$) at Ser177/181. This dephosphorylation led to the stabilization of $I{\kappa}B{\alpha}$ and inhibition of NF-${\kappa}B$ activity. Taken together, our results suggest that PTPN21 could be a valuable molecular target for regulation of inflammation in the skin by dephosphorylating p-$IKK{\beta}$ and inhibiting NF-${\kappa}B$ signaling.

• International Journal of Oral Biology
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• v.42 no.3
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• pp.137-142
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• 2017

To determine the effect of the tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$) in odontoclast formation, we administrated a $TNF-{\alpha}$ inhibitor in rats with diabetes rats with periodontitis. The rats included in the study were divided into three groups: control rats without diabetes or periodontitis (the C group), rats with periodontitis and diabetes (the PD group), and rats with periodontitis and diabetes treated by infliximab, the TNF inhibitor (the PD+infliximab group). The PD and PD+infliximab groups received intravenous administrations of streptozotocin (STZ, 50 mg/kg) to induce diabetes. After 7 days of STZ injections, the mandibular first molars were ligatured to induce periodontitis. The PD+infliximab group was intrapenitoneally administrated by infliximab (5 mg/kg). On days 3 and 20 after the ligature administration, odontoclast formation along root surfaces was evaluated by tartrate resistant acid phosphatase (TRAP) staining and cathepsin K immunohistochemistry. On day 3, the number of TRAP- and cathepsin K-positive cells increased more so in the PD group than in the C group. The PD+infliximab group showed a lower number of positive cells than the PD group. There was no difference in all the groups on day 20. On day 3, the cathepsin-K positive multinucleated and mononucleated cells were higher in the PD group than in the C group. The number of cathepsin-K positive multinucleated cells was lower in the PD+infliximab group than in the PD group. The PD group showed more cathepsin K-positive cells in the furcation and distal surfaces than the c group. The Cathepsin K-positive cells of the PD+infliximab group were lower than that of the PD group in furcation. These results suggest that $TNF-{\alpha}$ stimulates odontoclast formation in diabetes with periodontitis.

• Biomolecules & Therapeutics
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• v.20 no.1
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• pp.43-49
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• 2012

Stimulation of mast cells through the high affinity IgE receptor (Fc${\varepsilon}$RI) induces degranulation, lipid mediator release, and cytokine secretion leading to allergic reactions. Although various signaling pathways have been characterized to be involved in the Fc${\varepsilon}$RI-mediated responses, little is known about the precious mechanism for the expression of tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) in mast cells. Here, we report that rapamycin, a specific inhibitor of mammalian target of rapamycin (mTOR), reduces the expression of TNF-${\alpha}$ in rat basophilic leukemia (RBL-2H3) cells. IgE or specific antigen stimulation of RBL-2H3 cells increases the expression of TNF-${\alpha}$ and activates various signaling molecules including S6K1, Akt and p38 MAPK. Rapamycin specifically inhibits antigeninduced TNF-${\alpha}$ mRNA level, while other kinase inhibitors have no effect on TNF-${\alpha}$ mRNA level. These data indicate that mTOR signaling pathway is the main regulation mechanism for antigen-induced TNF-${\alpha}$ expression. TNF-${\alpha}$ mRNA stability analysis using reporter construct containing TNF-${\alpha}$ adenylate/uridylate-rich elements (AREs) shows that rapamycin destabilizes TNF-${\alpha}$ mRNA via regulating the AU-rich element of TNF-${\alpha}$ mRNA. The antigen-induced activation of S6K1 is inhibited by specific kinase inhibitors including mTOR, PI3K, PKC and $Ca^{2+}$chelator inhibitor, while TNF-${\alpha}$ mRNA level is reduced only by rapamycin treatment. These data suggest that the effects of rapamycin on the expression of TNF-${\alpha}$ mRNA are not mediated by S6K1 but regulated by mTOR. Taken together, our results reveal that mTOR signaling pathway is a novel regulation mechanism for antigen-induced TNF-${\alpha}$ expression in RBL-2H3 cells.

• Biomolecules & Therapeutics
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• v.19 no.4
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• pp.438-444
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• 2011

The mushroom Coriolus versicolor contains biologically active polysaccharides, most of which belong to the ${\beta}$-glucan group. Diverse physicochemical properties, due to different sources and isolated types of ${\beta}$-glucans, can induce distinct biological activities. We investigated the effects of ${\beta}$-glucans from C. versicolor on phagocytic activity, nitric oxide (NO), TNF-${\alpha}$ production, and signaling of dectin-1, a well-known ${\beta}$-glucan receptor, in macrophages. ${\beta}$-Glucans increased phagocytic activity and TNF-${\alpha}$ and NO-iNOS/eNOS production. Laminarin, a specific inhibitor of dectin-1, showed strong inhibitory effects on phagocytosis and subsequent TNF-${\alpha}$, iNOS, and eNOS production increased by ${\beta}$-glucans, indicating that ${\beta}$-glucans reacts with dectin-1 receptors. We examined whether the aforementioned cytokines were involved in the signaling pathway from the dectin-1 receptor to phagocytosis, and found that the inhibition of iNOS, eNOS, and TNF-${\alpha}$ receptors significantly decreased ${\beta}$-glucan-induced phagocytosis. In conclusion, our study showed that dectin-1 signaling, triggered by ${\beta}$-glucans, subsequently elicited TNF-${\alpha}$ and NO-iNOS/eNOS production, and that these molecules seem to act as secondary molecules that cause eventual phagocytosis by macrophages. These findings suggest that C. versicolor could be used as a nutritional medicine that may be useful in the treatment of infectious disease.

• Molecular & Cellular Toxicology
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• v.1 no.3
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• pp.196-202
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• 2005

Nitric oxide (NO) is a small, diffusible, and highly reactive molecule, which plays dichotomous regulatory roles under physiological and pathological conditions. NO promotes apoptosis in some cells, and inhibits apoptosis in other cells. In the present study, we attempted to characterize the NO signaling pathway and cellular response in PC12 cells treated with cytokines. $IFN{\gamma}\;and\;TNF{\alpha}$ treatment resulted in a synergistic increase of nitrite accumulation, with the induction of inducible nitric oxide synthase (iNOS) in the PC12 cells. Moreover, as nitrite concentration increased, cell viability decreased. In order to explore MAP kinase involvement in nitric oxide production resultant from $IFN{\gamma}\;and\;TNF{\alpha}$ stimulation, we measured the activation of MAP kinase using specific MAP kinase inhibitors. PC12 cells pretreated with SB203580, a p38 MAP kinase-specific inhibitor, resulted in the inhibition of iNOS expression and NO production. However, PD98059, an ERK/MAP kinase-specific inhibitor, was not observed to exert such an effect. In addition, Stat1 activated by $IFN{\gamma}\;and\;TNF{\alpha}$ was interacted with p38 MAPK. These data suggest that p38 MAP kinase mediates cytokine-mediated iNOS expression in the PC12 cells, and Jak/Stat pathway interferes with p38 MAPK signaling pathway.

• Archives of Pharmacal Research
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• v.23 no.4
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• pp.332-337
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• 2000

This study describes the synthesis, in vitro evaluation and molecular modeling study of novel compounds for the inhibition of TNF-$\alpha$production, Among these compounds, 2-[3-(cyclopentyloxy)-4-methoxyphenyl]-1-isoindolinone (9) was selected as a lead compound and its pyridine derivative 10 was more potent in activity and safer than rolipram.

• Journal of Microbiology and Biotechnology
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• v.30 no.12
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• pp.1810-1818
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• 2020

Inhibitor K562 (IK) protein was first isolated from the culture medium of K562 cells, a leukemia cell line, and is an inhibitory regulator of interferon-γ-induced major histocompatibility complex class II expression. Recently, exogenous truncated IK (tIK) protein showed potential as a therapeutic agent for inflammation-related diseases. In this study, we designed a novel putative anti-inflammatory peptide derived from tIK protein based on homology modeling of the human interleukin-10 (hIL-10) structure, and investigated whether the peptide exerted inhibitory effects against pro-inflammatory cytokines such as IL-17 and tumor necrosis factor-α (TNF-α). The peptide contains key residues involved in binding hIL-10 to the IL-10 receptor, and exerted strong inhibitory effects on IL-17 (43.8%) and TNF-α (50.7%). In addition, we used circular dichroism spectroscopy to confirm that the peptide is usually present in a random coil configuration in aqueous solution. In terms of toxicity, the peptide was found to be biologically safe. The mechanisms by which the short peptide derived from human tIK protein exerts inhibitory effects against IL-17 and TNF-α should be explored further. We also evaluated the feasibility of using this novel peptide in skincare products.

• Fisheries and Aquatic Sciences
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• v.22 no.3
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• pp.7.1-7.10
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• 2019

Sargassum serratifolium ethanolic extract has been known for strong antioxidant and anti-inflammatory properties. We prepared hexane fraction from the ethanolic extract of S. serratifolium (HSS) to improve biological activities. In this study, we investigated the effects of HSS on the inhibition of tumor necrosis factor (TNF)-${\alpha}$-induced monocyte adhesion to human umbilical vein endothelial cells (HUVECs). We found that HSS suppressed the production of cell adhesion molecules such as intracellular adhesion molecule-1 and vascular cell adhesion molecule-1 in TNF-${\alpha}$-induced HUVECs. Moreover, TNF-${\alpha}$-induced production of monocyte chemoattractant protein 1 and keratinocyte chemoattractant was inhibited by HSS treatment. HSS suppressed TNF-${\alpha}$-induced nuclear factor kappa B ($NF-{\kappa}B$) activation via preventing proteolytic degradation of inhibitor ${\kappa}B-{\alpha}$. HSS induced the production of heme oxygenase 1 via translocation of Nrf2 into the nucleus in TNF-${\alpha}$-treated HUVECs. Overall, HSS alleviated vascular inflammation through the downregulation of $NF-{\kappa}B$ activation and the upregulation of Nrf2 activation in TNF-${\alpha}$-induced HUVECs. These results indicate that HSS may be used as therapeutic agents for vascular inflammatory disorders.