• Title/Summary/Keyword: Activation factor

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ent-Kaurane Diterpenoids from Croton tonkinensis Inhibit LPS-induced Transcription Factor NF-${\kappa}{B}$ Activation and NO Production

  • Giang, Phan-Minh;Jin, Hui-Zi;Lee, Jung-Joon
    • Proceedings of the PSK Conference
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    • 2003.04a
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    • pp.120.1-120.1
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    • 2003
  • Nuclear factor-${\kappa}{B}$ (NF-${\kappa}{B}$) belongs to a group of homodimers and heterodimers of Rel/NF-${\kappa}{B}$ proteins that bind to DNA target sites, where they directly regulate gene transcription. The activation of NF-${\kappa}{B}$ has been shown to mediate inflammation and suppress apoptosis. Activated NF-${\kappa}{B}$ has been found n various inflammatory diseases such as rheumatoid arthritis, Atherosclerosis, asthma, nflammatory bowel disease, and Helicobacter pylori-associated gastritis and associated with cancer, cachexia, diabetes, euthyroid sick syndrome, and AIDS. (omitted)

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Endoplasmic Reticulum Stress Induces CAP2 Expression Promoting Epithelial-Mesenchymal Transition in Liver Cancer Cells

  • Yoon, Sarah;Shin, Boram;Woo, Hyun Goo
    • Molecules and Cells
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    • v.44 no.8
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    • pp.569-579
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    • 2021
  • Cyclase-associated protein 2 (CAP2) has been addressed as a candidate biomarker in various cancer types. Previously, we have shown that CAP2 is expressed during multi-step hepatocarcinogenesis; however, its underlying mechanisms in liver cancer cells are not fully elucidated yet. Here, we demonstrated that endoplasmic reticulum (ER) stress induced CAP2 expression, and which promoted migration and invasion of liver cancer cells. We also found that the ER stress-induced CAP2 expression is mediated through activation of protein kinase C epsilon (PKCε) and the promotor binding of activating transcription factor 2 (ATF2). In addition, we further demonstrated that CAP2 expression promoted epithelial-mesenchymal transition (EMT) through activation of Rac1 and ERK. In conclusion, we suggest that ER stress induces CAP2 expression promoting EMT in liver cancer cells. Our results shed light on the novel functions of CAP2 in the metastatic process of liver cancer cells.

Study on the Combustion Kinetics of the Imported Bituminous Coal (수입 유연탄의 연소특성에 관한 연구)

  • Oh C.S.;Jin G.T.;Choi I.S.;Hong S.S.
    • The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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    • v.16 no.4
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    • pp.415-420
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    • 1987
  • The combustion kinetics of the imported bituminous coal was studied in the interme-diated heating rate. The activation energy and the frequency factor were obtained by experi-ment of the coal weight loss depending on the combustion time with Ih. furnace. The experi-ments were performed in the heating rates of $1,5,10^{\circ}C/sec\;or\;20^{\circ}C/sec\;at\;the\;600-900^{\circ}C$ maximum temperature, The values of the activation energy(E) which were calculated from the experimental data existed in the range from 3000cal/g-mol to 15000cal/g-mol, and those of the frequency $factor(1nk_O)$ were in the range from 4.5cm/sec to 11.5cm/sec.

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Saccharina japonica Attenuates the Allergic Inflammation in vivo and in vitro

  • Soo-Yeon Lee;Su-Jin Kim
    • Biomedical Science Letters
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    • v.28 no.4
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    • pp.276-283
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    • 2022
  • Saccharina japonica (SJ), a brown algae, exerts various pharmacological effects, including anti-oxidant, immunemodulating and anti-cancer properties. This study aimed to determine the pharmacological mechanism of SJ on atopic dermatitis in vivo and in vitro. We investigated the pharmacological effects of SJ on 2, 4-dinitrochlrobenzene (DNCB)- induced atopic dermatitis clinical symptoms in mice. Additionally, we evaluated the effects of SJ on the inflammatory cytokine production and nuclear factor-κB (NF-κB) activation in HaCaT cells. The findings of this study demonstrated that SJ reduced the clinical symptoms of atopic dermatitis, such as skin dryness, erythema and eczematous, and serum histamine and IgE level in DNCB-induced atopic dermatitis model. Additionally, SJ inhibited the NF-κB activation in atopic dermatitis-like skin lesion and HaCaT cells. Collectively, this result suggests that SJ could be used as a therapeutic agent for skin inflammation, including atopic dermatitis.

Gartanin enhances TRAIL-mediated liver cancer cell death through DR5 upregulation and autophagy activation

  • Dong-Oh Moon
    • Journal of Applied Biological Chemistry
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    • v.66
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    • pp.53-59
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    • 2023
  • Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has no effect on normal cells, but selectively can induce apoptosis in tumor cells. Gartanin, a xanthone compound in mangosteen, has been shown to inhibit cancer cell growth by arresting the cell cycle and inducing autophage. In this study, we revealed that gartanin can sensitize TRAIL-induced human liver cancer cell death. We also found that gartanin enhances DR5 expression, a death receptor for TRAIL. This effect appears to be related to CHOP activation associated with the response of endoplasmic reticulum stress. Gartanin treatment also inhibited p62 protein expression and cleaved LC3 to activate autophagy flux, which is related with TRAIL-induced cell death. Pretreatment with autophagy flux inhibitor, LY294002, inhibited gartanin-induced DR5 expression. In summary, our results reveal that the combined treatment of gartanin and TRAIL can be a valuable tool for cancer treatment.

The Anti-Inflammatory Activity of Eucommia ulmoides Oliv. Bark. Involves NF-κB Suppression and Nrf2-Dependent HO-1 Induction in BV-2 Microglial Cells

  • Kwon, Seung-Hwan;Ma, Shi-Xun;Hwang, Ji-Young;Ko, Yong-Hyun;Seo, Ji-Yeon;Lee, Bo-Ram;Lee, Seok-Yong;Jang, Choon-Gon
    • Biomolecules & Therapeutics
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    • v.24 no.3
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    • pp.268-282
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    • 2016
  • In the present study, we investigated the anti-inflammatory properties of Eucommia ulmoides Oliv. Bark. (EUE) in lipopolysaccharide (LPS)-stimulated microglial BV-2 cells and found that EUE inhibited LPS-mediated up-regulation of pro-inflammatory response factors. In addition, EUE inhibited the elevated production of pro-inflammatory cytokines, mediators, and reactive oxygen species (ROS) in LPS-stimulated BV-2 microglial cells. Subsequent mechanistic studies revealed that EUE suppressed LPS-induced phosphorylation of mitogen-activated protein kinases (MAPKs), phosphoinositide-3-kinase (PI3K)/Akt, glycogen synthase $kinase-3{\beta}$ ($GSK-3{\beta}$), and their downstream transcription factor, nuclear factor-kappa B ($NF-{\kappa}B$). EUE also blocked the nuclear translocation of $NF-{\kappa}B$ and inhibited its binding to DNA. We next demonstrated that EUE induced the nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) and upregulated heme oxygenase-1 (HO-1) expression. We determined that the significant up-regulation of HO-1 expression by EUE was a consequence of Nrf2 nuclear translocation; furthermore, EUE increased the DNA binding of Nrf2. In contrast, zinc protoporphyrin (ZnPP), a specific HO-1 inhibitor, blocked the ability of EUE to inhibit NO and $PGE_2$ production, indicating the vital role of HO-1. Overall, our results indicate that EUE inhibits pro-inflammatory responses by modulating MAPKs, PI3K/Akt, and $GSK-3{\beta}$, consequently suppressing $NF-{\kappa}B$ activation and inducing Nrf2-dependent HO-1 activation.

Korean Red Ginseng mitigates spinal demyelination in a model of acute multiple sclerosis by downregulating p38 mitogen-activated protein kinase and nuclear factor-κB signaling pathways

  • Lee, Min Jung;Chang, Byung Joon;Oh, Seikwan;Nah, Seung-Yeol;Cho, Ik-Hyun
    • Journal of Ginseng Research
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    • v.42 no.4
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    • pp.436-446
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    • 2018
  • Background: The potential therapeutic values of Korean Red Ginseng extract (KRGE) in autoimmune disorders of nervous system have not been fully investigated. Methods: We used an acute experimental autoimmune encephalomyelitis animal model of multiple sclerosis and determined the effects and mechanism of KRGE on spinal myelination. Results: Pretreatment with KRGE (100 mg/kg, orally) for 10 days before immunization with myelin basic protein $(MBP)_{68-82}$ peptide exerted a protective effect against demyelination in the spinal cord, with inhibited recruitment and activation of immune cells including microglia, decreased mRNA expression of detrimental inflammatory mediators (interleukin-6, interferon-${\gamma}$, and cyclooxygenase-2), but increased mRNA expression of protective inflammatory mediators (insulin-like growth factor ${\beta}1$, transforming growth factor ${\beta}$, and vascular endothelial growth factor-1). These results were associated with significant downregulation of p38 mitogen-activated protein kinase and nuclear factor-${\kappa}B$ signaling pathways in microglia/macrophages, T cells, and astrocytes. Conclusion: Our findings suggest that KRGE alleviates spinal demyelination in acute experimental autoimmune encephalomyelitis through inhibiting the activation of the p38 mitogen-activated protein kinase/nuclear factor-${\kappa}B$ signaling pathway. Therefore, KRGE might be used as a new therapeutic for autoimmune disorders such as multiple sclerosis, although further investigation is needed.

Activation of pannexin-1 mediates triglyceride-induced macrophage cell death

  • Jung, Byung Chul;Kim, Sung Hoon;Lim, Jaewon;Kim, Yoon Suk
    • BMB Reports
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    • v.53 no.11
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    • pp.588-593
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    • 2020
  • The accumulation of triglycerides (TGs) in macrophages induces cell death, a risk factor in the pathogenesis of atherosclerosis. We had previously reported that TG-induced macrophage death is triggered by caspase-1 and -2, therefore we investigated the mechanism underlying this phenomenon. We found that potassium efflux is increased in TG-treated THP-1 macrophages and that the inhibition of potassium efflux blocks TG-induced cell death as well as caspase-1 and -2 activation. Furthermore, reducing ATP concentration (known to induce potassium efflux), restored cell viability and caspase-1 and -2 activity. The activation of pannexin-1 (a channel that releases ATP), was increased after TG treatment in THP-1 macrophages. Inhibition of pannexin-1 activity using its inhibitor, probenecid, recovered cell viability and blocked the activation of caspase-1 and -2 in TG-treated macrophages. These results suggest that TG-induced THP-1 macrophage cell death is induced via pannexin-1 activation, which increases extracellular ATP, leading to an increase in potassium efflux.

Thermal Analysis and Equivalent Lifetime Prediction of Insulation Material for Nuclear Power Cable (원전 케이블용 절연재료의 열분석과 등가수명)

  • Kim, Ji-Yeon;Yang, Jong-Suk;Park, Kyeung-Heum;Seong, Baek-Yong;Bang, Jeong-Hwan;Park, Dae-Hee
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.29 no.1
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    • pp.17-22
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    • 2016
  • The activation energy of a material is an important factor that significantly affects the lifetime and can be used to develop a degradation model. In this study, a thermal analysis was carried out to evaluate and collect quantitative data on the degradation of insulation materials like EPR and CSP used for nuclear power plant cables. The activation energy was determined from the relationship between log ${\beta}$ and 1/T based on the Flynn.Wall.Ozawa method, by a TGA test. The activation energy was also derived from the relationship between ln(t) and 1/T based on isothermal analysis, by an OIT test. The activation energy of EPR derived from thermal analysis was used to calculate the accelerated aging time corresponding to the number of years of use, employing the Arrhenius equation, and determine the elongation corresponding to the accelerated aging time.

Effects of Curcumin on the Microglial Activation (Curcumin이 microglia의 활성화에 미치는 영향)

  • 정기경;이상진;이선우;강석연;김태균;강주혜;홍성렬;주일로;김승희
    • YAKHAK HOEJI
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    • v.44 no.5
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    • pp.448-454
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    • 2000
  • Microglia, brain resident macrophages, play a central role in the inflammatory responses of the brain and are activated in brain injuries and several neurodegenerative diseases such as Alzheimer's and Parkinson's disease, thereby aggravating the course of these diseases. In this study, the effects of plantderived compounds such as curcumin or gingerol on the microglial activation were examined. Microglial cultures were prepared from 2~3 week mixed primary glial cultures obtained from the cerebral cortex of 1~2 day old rats and identified by immunocytochemistry using microglial-specific antibody OX-42. Microglia were activated by lipopolysaccharide (LPS) and interferon-${\gamma}$ (IFN-${\gamma}$) and the effect of curcumin or 6-gingerol on the microglial activation was examined. Specific parameters measured to monitor microglial activation were nitric oxide (NO), prostaglandin E$_2$(PGE$_2$) and tumor necrosis factor-$\alpha$ (TNF-$\alpha$) release. Curcumin (1~10 $\mu$M) inhibited NO release induced by LPS and IFN-${\gamma}$ in a dose-dependent manner whereas 6-gingerol (2~20 $\mu$M) did not have any effect on LPS/IFN-${\gamma}$-induced NO release. The levels of PGE$_2$and TNF-$\alpha$ induced by LPS and IFN-${\gamma}$ were also inhibited by 1~10 $\mu$M curcumin in a dose-dependent manner. These results showed that curcumin could modulate microglial activation.

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