• Journal of Life Science
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• v.17 no.10
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• pp.1447-1451
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• 2007

Through the screening of marine natural compounds that inhibit cancer cell proliferation, we previously reported that pectenotoxin-2 (PTX-2) isolated from marine sponges exhibits selective cytotoxicity against several cell lines in p53-deficient tumor cells compared to those with functional p53. However, the molecular mechanisms of its anti-proliferative action on malignant cell growth are not completely known. To further explore the mechanisms of its anti-cancer activity and to test whether the status of p53 in liver cancer cells correlates with their chemo-sensitivities to PTX-2, we used two well-known hepatocarcinoma cell lines, p53-deficient Hep3B and p53-wild type HepG2. We have demonstrated that PTX-2 markedly inhibits Hep3B cell growth and induces apoptosis whereas HepG2 cells are much more resistant to PTX-2 suggesting that PTX-2 seems to act by p53-independent cytotoxic mechanism. The apoptosis induced by PTX-2 in Hep3B cells was associated with the modulation of DNA fragmentation factor (DFF) family proteins, up-regulation of pro-apoptotic Bcl-2 family members such as Bax and Bcl-xS and activation of caspases (caspase-3, -8 and -9). Blockade of the caspase-3 activity by caspase-3 inhibitor, z-DEVD-fmk, prevented the PTX-2-induced growth inhibition in Hep3B cells. Moreover, treatment with PTX-2 also induced phosphorylation of AKT and extracellular-signal regulating kinase (ERK), but not c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MARK). Specific inhibitors of PI3K inhibitor (LY294002) and ERK1/2 inhibitor (PD98059) significantly blocks PTX-2-induced-anti-proliferative effects, whereas a JNK inhibitor (SP600125) and a p38 MAPK inhibitor (SB203580) have no significant effects demonstrating that the pro-apoptotic effect of PTX-2 mediated through activation of AKT and ERK signal pathway in Hep3B cells.

• Journal of Life Science
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• v.19 no.7
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• pp.949-955
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• 2009

Mucosal epithelia sense external stress signals and transmit them to the intracellular cascade responses. Ribotoxic stress-producing chemicals such as deoxynivalenol (DON) or other trichothecene mycotoxins have been linked with gastrointestinal inflammatory diseases by Fusarium-contamination. The purpose of this study was to test the hypothesis that DON evokes the epithelial sentinel signals of RNA-dependent protein kinase (PKR) and early growth response gene 1 (EGR-1), which together contribute to the pro-inflammatory cytokine interleukin 8 (IL-8) in human intestinal epithelial cells. PKR suppression by the dominant negative PKR expression attenuated DON-stimulated interleukin-8 production. Moreover, 1L-8 transcriptional activation by DON was also reduced by PKR inhibition in the human intestinal epithelial cells. Treatment with the PKR inhibitor also suppressed EGR-1 promoter activity, mRNA and protein induction, although mitogen-activated protein (MAP) kinases such as extracellular signal-regulated protein kinases (ERK) 1/2, p38, c-Jun N-terminal Kinase (INK) were little affected or even enhanced in presence of a PKR inhibitor. These patterns were also compared in the EGR-1-suppressed cells, which showed much more suppressed production of 1L-8. All things taken into consideration, DON-activated sentinel signals of EGR-1 via PKR mediated interleukin-8 production in human intestinal epithelial cells, which provide insight into the possible general mechanism associated with mucosal inflammation as an intestinal toxic insult by ribotoxic trichothecene mycotoxins.

• Journal of Life Science
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• v.33 no.6
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• pp.471-480
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• 2023

This study was designed to evaluate the anti-inflammatory effects of Rumohra adiantiformis extracts fermented with Bovista plumbea mycelium (B-RAE) in LPS-stimulated RAW 264.7 cells. The total polyphenol and total flavonoid content of B-RAE were 379.26±7.77 mg/g and 50.85±3.08 mg/g, respectively. The results of measuring the antioxidant activity of B-RAE showed that it scavenges 2, 2-diphenyl-1-picrylhydrazyl (DPPH), 2, 2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), and superoxide anion radical in a dose-dependent manner. B-RAE inhibited nitric oxide (NO) production in a dose-dependent manner without affecting cell viability. The gene expression of pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin-lβ (IL-1β), and IL-6 was measured using real time quantitative reverse transcription PCR (qRT-PCR). We found that, compared to the LPS-treated group, B-RAE significantly reduced the mRNA levels of the pro-inflammatory cytokines in a concentration-dependent manner. The expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), the phosphorylation of transcription factors such as nuclear factor-κB (NF-κB), and the mitogen-activated protein kinase (MAPK) signaling pathway proteins were assessed using Western blot analysis. We found that B-RAE significantly suppressed the expression of iNOS and COX-2, but their expression was increased by LPS treatment. In addition, the phosphorylation of NF-κB and IκB, which was increased by LPS treatment, was reduced with B-RAE treatment. The effect of B-RAE on the phosphorylation of the MAPK signaling pathway proteins was measured, and the phosphorylation of extracellular signal-regulated kinase (ERK) and the p38 MAPK proteins decreased in a dose-dependent manner, while the phosphorylation of c-Jun N-terminal kinase (JNK) increased. These anti-inflammatory effects of B-RAE may thus have been achieved through the high antioxidant activity, the inhibition of NO production through the suppression of iNOS and COX-2 expression, the inhibition of the NF-κB pathway, and the suppression of pro-inflammatory cytokine expression.

• The Korea Journal of Herbology
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• v.29 no.6
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• pp.117-123
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• 2014

Objectives : Sinhyowoldo-san (SHWDS) is said to be a traditional medicine used for shigellosis, abdominal pain, diarrhea. But mechanism of SHWDS mediated-modulation of immune function is not sufficiently understood. To ascertain the molecular mechanisms of SHWDS 70% EtOH extract on pharmacological and biochemical actions in inflammation, we researched the effect of pro-inflammatory mediators in phorbol-12-myristate-13-acetate (PMA)+ A23187-activated human mast cell line (HMC-1). Methods : In the present research, cell viability was measured by MTS assay. pro-inflammatory cytokine production was measured by performing enzyme-linked immunosorbent assay (ELISA), reverse transcription polymerase chain reaction (RT-PCR), and western blot analysis to analyze the activation of mitogen-activated protein kinases (MAPKs), nuclear factor kappa-light-chain-enhancer of activated B cells ($NF-{\kappa}B$). The investigation focused on whether SHWDS inhibited the expressions of interleukin-6 (IL-6), interleukin-8 (IL-8), MAPKs and $NF-{\kappa}B$ in PMA+A23187-activated HMC-1 cells. Results : SHWDS has no cytotoxicity at measured concentration (50, 100, and $250{\mu}g/ml$). SHWDS ($250{\mu}g/ml$) inhibits pro-inflammatory cytokine expression in PMA+ A23187-activated HMC-1 cells. Moreover, SHWDS inhibited cyclooxygenase (COX)-2 expression. In activated HMC-1 cells, SHWDS suppressed phosphorylation of extracellular signal-regulated kinase (ERK 1/2) and c-jun N-terminal Kinase (JNK 1/2). Then, SHWDS suppressed activation of nuclear factor $NF-{\kappa}B$ in nuclear, degradation of IkB ${\alpha}$ in cytoplasm. Conclusions : We propose that SHWDS has an anti-inflammatory therapeutic potential, which may result from inhibition of ERK 1/2, JNK 1/2 phosphorylation and $NF-{\kappa}B$ activation, thereby decreasing the expression of pro-inflammatory genes.

• Food Science and Preservation
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• v.24 no.8
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• pp.1149-1157
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• 2017

Inflammation is the first response of the immune system to infection or irritation in our body. The use of medicinal plants has been widely applied as an alternative source for drug development. One of marine natural resources, the anti-inflammatory effect of Ishige sinicola ethanol extract (ISEE), was evaluated by using LPS-induced RAW 264.7 cell and mice model. As a result, the production of nitric oxide (NO) and pro-inflammatory cytokines (IL-6, IL-$1{\beta}$, TNF-${\alpha}$) were inhibited with increasing concentration of ISEE without any cytotoxicity. Furthermore, ISEE suppressed the expression of not only inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), nuclear factor-kappa B (NF-${\kappa}B$) p65, and mitogen-activated protein kinases (MAPKs), including extracellular signal-regulated kinase (ERK) 1/2, p38, and c-Jun N-terminal kinase (JNK) in a dose-dependent manner. In mice ear edema test, the formation of edema was reduced at the highest dosage of ISEE and the reduction of the number of infiltrated mast cells was observed in histological analysis. These results indicate that ISEE has a potent anti-inflammatory activity and can be used as a pharmaceutical material for many kinds of inflammatory disease.

• Journal of Life Science
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• v.32 no.11
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• pp.865-871
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• 2022

Tenebrio molitor larvae is well known as edible insect. Then, although it has been widely studied that Tenebrio molitor larvae has various bioactive functions such as antioxidant, anti-wrinkle, and anticancer. Nevertheless, antioxidant effects of Tenebrio molitor larvae water extract (TMH) has not been well described in Adult Retina Pigment Epithelial cell line (ARPE-19). In this study, we demonstrated that antioxidant effects of TMH against H₂O₂-induced oxidative stress in ARPE-19. Thus, we selected for our studies and performed a series of dose-response assay to determine the working concentration that lead to a consistent and high degree of cytotoxicity, which we defined as the level of H₂O₂ that killed 40% of the ARPE-19 cells. ARPE-19 cells were pre-treated with various concentrations of TMH (0.1 up to 2 mg/ml) before exposure to 300 µM H₂O₂. As we expected, TMH effectively prevented ARPE-19 cells from 300 µM H₂O₂-induced cell death in a dose-dependent manner. Furthermore, TMH inhibited the phosphorylation of mitogen-activated protein kinases (MAPKs) such as extracellular signal regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38. Overall, the inhibitory effects of TMH on H₂O₂-induced apoptosis and oxidative stress were associated with the protection cleaved caspase-3, Bax, Bcl-2, and HO-1. The TMH suppressed H₂O₂-induced cell membrane leakage and oxidative stress in ARPE-19 cells. Thus, these results suggest that the TMH plays an important role in antioxidant effect in ARPE-19.

• Journal of Life Science
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• v.33 no.4
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• pp.305-314
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• 2023

Ultraviolet B (UVB) irradiation causes skin diseases by inducing cellular oxidative stress, photoaging, and inflammation. This study aimed to investigate the protective effects of morin against UVB-induced oxidative stress in normal human dermal fibroblasts (NHDFs). Morin has been reported to be a potential therapeutic candidate for oxidative stress-mediated diseases, neurodegenerative diseases, and inflammation. Since morin has been identified as a potential antioxidant, we speculated that morin could alleviate UVB-induced apoptosis in NHDFs. Cell viability and intracellular reactive oxygen species (ROS) levels were measured using the MTT assay, H2DCFDA, and the DHE staining method, respectively. Lipid peroxidation and protein carbonyl formation were tested using ELISA kits. DNA fragmentation and comet assay were used to assess DNA damage. Apoptotic bodies were analyzed using Hoechst 33342 staining and TUNEL assay. The expression of apoptosis-related proteins was examined using Western blot analysis. Morin showed a cyto-protective effect by scavenging UVB-induced ROS, increasing the expression of antioxidant-related proteins and inhibiting UVB-induced oxidative alterations such as lipid peroxidation, protein carbonylation, and DNA damage. Morin protects against UVB-induced cell apoptosis by inhibiting Bcl-2-associated X protein, caspase-9, and caspase-3 expression, while increasing the expression of the anti-apoptotic protein Bcl-2. These effects of morin were conferred through decreased phosphorylation of p38 and c-Jun N-terminal kinase 1/2. The results demonstrated that morin may be developed as a preventive/therapeutic drug to be used to prevent UVB-induced skin damage.