• Journal of Veterinary Science
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• v.21 no.3
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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.

• BMB Reports
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• v.45 no.2
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• pp.114-119
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• 2012

Salsolinol (1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline) is a compound derived from dopamine metabolism and is capable of causing dopaminergic neurodegeneration. Oxidative modification of neurofilament proteins has been implicated in the pathogenesis of neurodegenerative disorders. In this study, oxidative modification of neurofilament-L (NF-L) by salsolinol and the inhibitory effects of histidyl dipeptides on NF-L modification were investigated. When NF-L was incubated with 0.5 mM salsolinol, the aggregation of protein was increased in a time-dependent manner. We also found that the generation of hydroxyl radicals (${\bullet}OH$) was linear with respect to the concentrations of salsolinol as a function of incubation time. NF-L exposure to salsolinol produced losses of glutamate, lysine and proline residues. These results suggest that the aggregation of NF-L by salsolinol may be due to oxidative damage resulting from free radicals. Carnosine, histidyl dipeptide, is involved in many cellular defense processes, including free radical detoxification. Carnosine, and anserine were shown to significantly prevent salsolinol-mediated NF-L aggregation. Both compounds also inhibited the generation of ${\bullet}OH$ induced by salsolinol. The results indicated that carnosine and related compounds may prevent salsolinol-mediated NF-L modification via free radical scavenging.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.92.1-92.1
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• 2003

In our search for NF-kB inhibitors from natural resources, we have previously identified two structurally related dilignans, manassantin A and B as specific inhibitors of NF-kB activation from Saururus chinensis. However, their molecular mechanism of action remains unclear. We here demonstrate that manassantin A and B are potent inhibitors of NF-kB activation by the suppression of transciptional activity of RelA/p65 subunit of NF-kB. These compounds significantly inhibited the induced expression of NF-kB reporter gene by LPS or TNF-a in a dose-dependent manner. (omitted)

• Biomedical Science Letters
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• v.20 no.1
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• pp.14-24
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• 2014

Hypoxia is one of the main reasons for islet apoptosis after transplantation as well as during isolation. In this study, we attempted to determine the potential usefulness of NF-${\kappa}B$ inhibitor for suppression of hypoxia-induced ${\beta}$-cell apoptosis as well as the relationship between IP-10 induction and ${\beta}$-cell apoptosis in hypoxia. To accomplish this, we cultured the mouse pancreatic ${\beta}$-cell line MIN6 in hypoxia (1% $O_2$). Among several examined chemokines, only IP-10 mRNA expression was induced under hypoxia, and this induced IP-10 expression was due to NF-${\kappa}B$ activity. Since a previous study suggested that IP-10 mediates ${\beta}$-cell apoptosis, we measured hypoxia-induced IP-10 protein and examined the effect of anti-IP-10 neutralizing Ab on hypoxia-induced ${\beta}$-cell apoptosis. However, IP-10 protein was not detected, and anti-IP-10 neutralizing Ab did not rescue hypoxia-induced MIN6 apoptosis, indicating that there is no relationship between hypoxia-induced IP-10 mRNA expression and hypoxia-induced ${\beta}$-cell apoptosis. Since it was still not clear if NF-${\kappa}B$ functions as an apoptotic or anti-apoptotic mediator in hypoxia-induced ${\beta}$-cell apoptosis, we examined possible involvement of NF-${\kappa}B$ in hypoxia-induced ${\beta}$-cell apoptosis. Treatment with 1 ${\mu}M$ NF-${\kappa}B$ inhibitor suppressed hypoxiainduced apoptosis by more than 50%, while 10 ${\mu}M$ AP-1 or 4 ${\mu}M$ NF-AT inhibitor did not, indicating involvement of NF-${\kappa}B$ in hypoxia-induced ${\beta}$-cell apoptosis. Overall, these results suggest that IP-10 is not involved in hypoxia-induced ${\beta}$-cell apoptosis, and that NF-${\kappa}B$ inhibitor can be useful for ameliorating hypoxia-induced ${\beta}$-cell apoptosis.

• Journal of Physiology & Pathology in Korean Medicine
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• v.34 no.6
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• pp.334-340
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• 2020

Nypa fruticans Wurmb. (NF) has been used as a folk remedy to treat inflammatory diseases in Asia. In this study, we aimed to investigate the protective effect of NF water extract on cerulein-induced acute pancreatitis (AP). To measure the protective effects of NF on AP, AP was induced via intraperitoneal injection of cerulein (50 ㎍/kg) hourly for 6 h in mice. NF water extract (100, 250, or 500 mg/kg) or saline was administrated to intraperitoneal injection 1 h before the first injection of cerulein. The mice were sacrificed at 6 h after the final injection of the cerulein. Pancreas, and blood sample were taken for further analysis. Administration of NF water extract inhibited the pancreatic injury, the elevation of pancreatic weight/ body weight ratio, and the elevation of serum digestive enzymes such as amylase and lipase during cerulein-induced AP in mice. Also, pancreas MPO activity, which represents neutrophil infiltration, was inhibited by administration of NF water extract. Taken together, administration of NF water extract reduces the severity of cerulein-induced AP, which suggests a clinical basis that NF could be a potential agent to prevent AP.

• Journal of Acupuncture Research
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• v.23 no.2
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• pp.61-72
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• 2006

Objectives : Human chondrocytes co-treated with Buthus martensi Karsch herbal acupuncture solution(BMK-HAS) extract produced significantly less NO compared with chondrocytes stimulated with $IL-1{\beta}$ alone Methods : Activation and translocation of and NF-kB DNA binding activity were determined by Western blotting and specific enzyme-linked immunosorbent assay. Results : The inhibition of NO production correlated with the suppression of induction and expression of nuclear factor-kB (NF-kB) and activation protein-1 (AP-1)-dependent gene. BMK-HAS inhibited the activation and translocation of NF-kB to the nucleus, indicating that BMK-HAS inhibits the $IL-1{\beta}-induced$ production of NO in human chondrocytes by interfering with the activation of NF-kB through a novel mechanism. In addition, BMK-HAS reduced prostaglandin E2 (PGE2)production in mouse peritoneal macrophages stimulated with lipopolysaccharide, whereas no influence on the activity of inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2) or cyclooxygenase-1 (COX-1) was observed. My data, therefore, suggest that BMK-HAS may be a therapeutically effective inhibitor of $IL-1{\beta}-induced$ inflammatory effects that are dependent on NF-kB activation in human OA chondrocytes. Conclusion : The results indicate that BMK-HAS exerts anti-inflammatory effects related to the inhibition of neutrophil functions and of NO and PGE2 production, which could be due to a decreased expression of iNOS and COX-2 through the transcription factors NF-kB and AP-1.

• Journal of Microbiology and Biotechnology
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• v.29 no.8
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• pp.1316-1323
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• 2019

Middle East respiratory syndrome coronavirus (MERS-CoV) is a newly emerging coronavirus which is zoonotic from bats and camels. Its infection in humans can be fatal especially in patients with preexisting conditions due to smoking and chronic obstructive pulmonary disease (COPD). Among the 25 proteins encoded by MERS-CoV, 5 accessory proteins seem to be involved in viral evasion of the host immune responses. Here we report that ORF4a, ORF4b, and ORF8b proteins, alone or in combination, effectively antagonize nuclear factor kappa B ($NF-{\kappa}B$) activation. Interestingly, the inhibition of $NF-{\kappa}B$ by MERS-CoV accessory proteins was mostly at the level of pattern recognition receptors: melanoma differentiation-associated gene 5 (MDA5). ORF4a and ORF4b additively inhibit MDA5-mediated activation of $NF-{\kappa}B$ while that of retinoic acid-inducible gene 1 (RIG-I) is largely not perturbed. Of note, ORF8b was found to be a novel antagonist of MDA5-mediated $NF-{\kappa}B$ activation. In addition, ORF8b also strongly inhibits Tank-binding kinase 1 (TBK1)-mediated induction of $NF-{\kappa}B$ signaling. Taken together, MERS-CoV accessory proteins are involved in viral escape of $NF-{\kappa}B$-mediated antiviral immune responses.

• Tuberculosis and Respiratory Diseases
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• v.65 no.6
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• pp.476-486
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• 2008

Background: TRAIL (TNF-related apoptosis inducing ligand) is a newly identified member of the TNF gene family which appears to have tumor-selective cytotoxicity due to the distinct decoy receptor system. TRAIL has direct access to caspase machinery and induces apoptosis regardless of p53 phenotype. Therefore, TRAIL has a therapeutic potential in lung cancer which frequently harbors p53 mutation in more than 50% of cases. However, it was shown that TRAIL also could activates $NF-{\kappa}B$ in some cell lines which might inhibit TRAIL-induced apoptosis. This study was designed to investigate whether TRAIL can activate $NF-{\kappa}B$ in lung cancer cell lines relatively resistant to TRAIL-induced apoptosis and inhibition of $NF-{\kappa}B$ activation using proteasome inhibitor MG132 which blocks $I{\kappa}B{\alpha}$ degradation can sensitize lung cancer cells to TRAIL-induced apoptosis. Methods: A549 (wt p53) and NCI-H1299 (null p53) lung cancer cells were used and cell viability test was done by MTT assay. Apoptosis was confirmed with Annexin V assay followed by FACS analysis. To study $NF-{\kappa}B$-dependent transcriptional activation, a luciferase reporter gene assay was used after making A549 and NCI-H1299 cells stably transfected with IgG ${\kappa}-NF-{\kappa}B$ luciferase construct. To investigate DNA binding of $NF-{\kappa}B$ activated by TRAIL, electromobility shift assay was used and supershift assay was done using anti-p65 antibody. Western blot was done for the study of $I{\kappa}B{\alpha}$ degradation. Results: A549 and NCI-H1299 cells were relatively resistant to TRAIL-induced apoptosis showing only 20~30% cell death even at the concentration 100 ng/ml, but MG132 ($3{\mu}M$) pre-treatment 1 hour prior to TRAIL addition greatly increased cell death more than 80%. Luciferase assay showed TRAIL-induced $NF-{\kappa}B$ transcriptional activity in both cell lines. Electromobility shift assay demonstrated DNA binding complex of $NF-{\kappa}B$ activated by TRAIL and supershift with p65 antibody. $I{\kappa}B{\alpha}$ degradation was proven by western blot. MG132 completely blocked both TRAIL-induced $NF-{\kappa}B$ dependent luciferase activity and DNA binding of $NF-{\kappa}B$. Conclusion: This results suggest that inhibition of $NF-{\kappa}B$ can be a potentially useful strategy to enhance TRAIL-induced tumor cell killing in lung cancer.

• Biomolecules & Therapeutics
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• v.23 no.5
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• pp.428-433
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• 2015

Acetylshikonin, a natural naphthoquinone derivative compound, has been used for treatment of inflammation and cancer. In the present study, we have investigated whether acetylshikonin could regulate the NF-${\kappa}B$ signaling pathway, thereby leading to suppression of tumorigenesis. We observed that acetylshikonin significantly reduced proliferation of several cancer cell lines, including human pancreatic PANC-1 cancer cells. In addition, acetylshikonin inhibited phorbol 12-myristate 13-acetate (PMA) or tumor necrosis-${\alpha}$ (TNF-${\alpha}$)-induced NF-${\kappa}B$ reporter activity. Proteome cytokine array and real-time RT-PCR results illustrated that acetylshikonin inhibition of PMA-induced production of cytokines was mediated at the transcriptional level and it was associated with suppression of NF-${\kappa}B$ activity and matrix metalloprotenases. Finally, we observed that an exposure of acetylshikonin significantly inhibited the anchorage-independent growth of PANC-1 cells. Together, our results indicate that acetylshikonin could serve as a promising therapeutic agent for future treatment of pancreatic cancer.

• Journal of Life Science
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• v.12 no.1
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• pp.55-60
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• 2002

The differentiation of skeletal muscle precursor cells in culture is marked by the transcriptional activation of muscle-specific genes and the morphological differentiation of myoblast into multinucleate myotube. In this study, we examined the effect of TSA (Trichostatin A) on WF-kB DNA binding activity and muscle cell fusion in the process of myogenesis. Under TSA treatment, C2C12 myoblast could not fuse to myotube and its NF-kB DNA binding activity was also blocked. To investigate whether these phenomenons were affected by TSA in direct or not, differentiation media (DM) used to differentiate cells without TSA was concentrated and added to C2C12 myoblast with TSA simultaneously. C2C12 myoblast was fused to myotube and NF-kB DNA binding activity was recovered. These results suggest that TSA affects on the differentiation of myoblast, perhaps through several factors, by inhibiting myoblst fusion and blocking NF-kB DNA binding activity.