• Toxicological Research
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• v.30 no.1
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• pp.19-25
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• 2014

Licochalcone (LC), a major phenolic retrochalcone from licorice, has anti-inflammatory activity. This study investigated the effects of licochalcone A (LCA) and licochalcone E (LCE) on Liver X receptor-${\alpha}$ ($LXR{\alpha}$)-mediated lipogenic gene expression and the molecular mechanisms underlying those effects. LCA and LCE antagonized the ability of $LXR{\alpha}$ agonists (T0901317 or GW3965) to increase sterol regulatory element binding protein-1c (SREBP-1c) expression and thereby inhibited target gene expression (e.g., FAS and ACC) in HepG2 cells. Moreover, treatment with LCA and LCE impaired $LXR{\alpha}/RXR{\alpha}$-induced CYP7A1-LXRE-luciferase (CYP7A1) transactivation. The AMPK-Sirt1 signaling pathway is an important regulator of energy metabolism and, therefore, a potential therapeutic target for metabolic diseases, including hepatic steatosis. We found here that LCE increased AMPK phosphorylation and Sirt1 expression. We conclude that LC inhibits SREBP-1c-mediated hepatic lipogenesis via activation of the AMPK/Sirt1 signaling pathway.

• The Korean Journal of Physiology and Pharmacology
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• v.26 no.6
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• pp.447-456
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• 2022

The present study was carried out to investigate the effect of Arctigenin on cell growth and the mechanism of cell death elicited by Arctigenin were examined in FaDu human pharyngeal carcinoma cells. To determine the apoptotic activity of Arctigenin in FaDu human pharyngeal carcinoma cells, cell viability assay, DAPI staining, caspase activation analysis, and immunoblotting were performed. Arctigenin inhibited the growth of cells in a dose-dependent manner and induced nuclear condensation and fragmentation. Arctigenin-treated cells showed caspase-3/7 activation and increased apoptosis versus control cells. FasL, a death ligand associated with extrinsic apoptotic signaling pathways, was up-regulated by Arctigenin treatment. Moreover, caspase-8, a part of the extrinsic apoptotic pathway, was activated by Arctigenin treatments. Expressions of anti-apoptotic factors such as Bcl-2 and Bcl-xL, components of the mitochondria-dependent intrinsic apoptosis pathway, significantly decreased following Arctigenin treatment. The expressions of pro-apoptotic factors such as BAX, BAD and caspase-9, and tumor suppressor -53 increased by Arctigenin treatments. In addition, Arctigenin activated caspase-3 and poly (ADP-ribose) polymerase (PARP) induced cell death. Arctigenin also inhibited the proliferation of FaDu cells by the suppression of p38, NF-κB, and Akt signaling pathways. These results suggest that Arctigenin may inhibit cell proliferation and induce apoptotic cell death in FaDu human pharyngeal carcinoma cells through both the mitochondria-mediated intrinsic pathway and the death receptor-mediated extrinsic pathway.

• Fisheries and Aquatic Sciences
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• v.26 no.2
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• pp.133-144
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• 2023

Auranofin is a US Food and Drug Administration (FDA)-approved anti-arthritis medication that functions as a thioredoxin reductase inhibitor. Spermidine, a polyamine present in marine algae, can exert various physiological functions. Herein, we examined the synergistic anticancer activity of auranofin and spermidine in hepatocellular carcinoma (HCC). Combined treatment with auranofin and spermidine suppressed cell viability more efficiently than either treatment alone in HCC Hep3B cells. The isobologram plotted by calculating the half maximal inhibitory concentration (IC₅₀) values of each drug indicated that the two drugs exhibited a synergistic effect. Based on the analysis of annexin V and cell cycle distribution, auranofin and spermidine markedly induced apoptosis in Hep3B cells. Moreover, auranofin and spermidine increased mitochondria-mediated apoptosis by promoting mitochondrial membrane potential (Δψm) loss. Auranofin and spermidine significantly increased reactive oxygen species (ROS) production in Hep3B cells, and the blocking ROS suppressed apoptosis induced by spermidine and auranofin. In addition, auranofin and spermidine reduced the expression of phosphorylated phosphatidylinositol-3 kinase (PI3K) and protein kinase B (Akt), and PI3K inhibitor accelerated auranofin- and spermidine-induced apoptosis. Using ROS scavenger and PI3K inhibitor, we revealed that ROS acts upstream of auranofin- and spermidine-induced apoptosis. Collectively, our study suggests that combination treatment with auranofin and spermidine could afford synergistic anticancer activity via ROS overproduction and reduced PI3K/Akt signaling pathway.

• BMB Reports
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• v.45 no.9
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• pp.496-508
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• 2012

Fas-associated protein with death domain (FADD), an adaptor that bridges death receptor signaling to the caspase cascade, is indispensible for the induction of extrinsic apoptotic cell death. Interest in the non-apoptotic function of FADD has greatly increased due to evidence that FADD-deficient mice or dominant-negative FADD transgenic mice result in embryonic lethality and an immune defect without showing apoptotic features. Numerous studies have suggested that FADD regulates cell cycle progression, proliferation, and autophagy, affecting these phenomena. Recently, programmed necrosis, also called necroptosis, was shown to be a key mechanism that induces embryonic lethality and an immune defect. Supporting these findings, FADD was shown to be involved in various necroptosis models. In this review, we summarize the mechanism of extrinsic apoptosis and necroptosis, and discuss the in vivo and in vitro roles of FADD in necroptosis induced by various stimuli.

• Fisheries and Aquatic Sciences
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• v.18 no.1
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• pp.35-44
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• 2015

We previously identified Streptomyces griseus as an anti-cancer agent (Kim et al., 2014). In this study, we isolated compounds from S. griseus and evaluated their anticancer effect and toxicity in vitro and in vivo. Preparative centrifugal partition chromatography (CPC) was used to obtain three compounds, cyclo($_{\small{L}}$-[4-hydroxyprolinyl]-$_{\small{L}}$-leucine], cyclo($_{\small{L}}$-Phe-trans-4-hydroxy-$_{\small{L}}$-Pro) and phenethyl acetate (PA). We chose PA, which had the highest anticancer activity, as a target compound for further experiments. PA induced the formation of apoptotic bodies, DNA fragmentation, DNA accumulation in $G_0/G_1$ phase, and reactive oxygen species (ROS) formation. Furthermore, PA treatment increased Bax/Bcl-xL expression, activated caspase-3, and cleaved poly-ADP-ribose polymerase (PARP) in HL-60 cells. Simultaneous evaluation in vitro and in vivo, revealed that PA exhibited no toxicity in Vero cells and zebrafish embryos. We revealed, for the first time, that PA generates ROS, and that this ROS accumulation induced the Bcl signaling pathway.

• Fisheries and Aquatic Sciences
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• v.17 no.3
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• pp.305-311
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• 2014

Dieckol is a polyphenol compound isolated from brown algae that has anti-oxidant, anti-inflammatory, and anti-tumor activity. We examined the anti-angiogenic effects of dieckol in endothelial cells under hypoxic conditions. Treatment with $CoCl_2$, a hypoxic mimetic agent, increased proliferation, adhesion, migration, and tube formation in HUVECs, as well as vessel sprouting in rat aortic rings, which correlated well with increased expression of hypoxia-inducible factor 1-alpha ($HIF1{\alpha}$) and ${\beta}1$-integrin. Dieckol suppressed $CoCl_2$-induced adhesion, migration, and tube formation in HUVECs and vessel sprouting in rat aortic rings. Dieckol treatment decreased $CoCl_2$-induced overexpression of $HIF1{\alpha}$ and its downstream signaling molecules, including ${\beta}1$-integrin/Fak, Akt/eNOS, and p38 MAPK. These results suggest that dieckol is a novel angiogenesis inhibitor and a potential treatment for angiogenesis-dependent diseases in humans, such as malignant tumors.

• Journal of Microbiology and Biotechnology
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• v.27 no.7
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• pp.1359-1366
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• 2017

(E)-2-Methoxy-4-(3-(4-methoxyphenyl)prop-1-en-1-yl)phenol (MMPP), derived from butenal, is a recently synthesized Maillard reaction product. Owing to its novelty, little is known about the function of MMPP. In this study, we elucidated the effects of MMPP on apoptosis in cervical cancer by using the HeLa cervical cancer cell line, which is widely used in cancer research. We observed that MMPP was cytotoxic to HeLa cells and induced activation of caspase-3, -8, and -9, without affecting the expression of the viral oncogenes E6 and E7. In particular, the expression of the death receptors DR5 and FAS was significantly increased by MMPP treatment. There were no significant alterations of mitochondrial intrinsic factors. Taking all these results together, our findings show that MMPP primarily induces apoptosis in HeLa cervical cancer cells via the extrinsic apoptotic signaling pathway, accompanied by an enhanced expression of death receptors.

• Fisheries and Aquatic Sciences
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• v.15 no.1
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• pp.29-36
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• 2012

Osteosarcoma is the most common primary malignancy of bone, and patients often develop pulmonary metastasis. The mechanisms underlying osteosarcoma metastasis remain to be elucidated. Recently, anti-inflammatory agents were shown to be useful in the treatment of tumor progression. We previously isolated a natural anti-inflammatory peptide from the seahorse Hippocampus kuda bleeler. Here, we examined the antitumor metastatic activity of this peptide and investigated its mechanism. The peptide significantly inhibited 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced invasive migration of human osteosarcoma MG-63 cells. Its inhibitory effect on invasive migration was associated with reduced expression of matrix metalloproteinases (MMP1 and MMP2). In addition, TPA stimulation increased intracellular reactive oxygen species (ROS) generation and small GTPase Rac1 expression, whereas the peptide decreased ROS generation and Rac1 activation. Taken together, these results suggest that the peptide inhibits invasive migration of MG-63 osteosarcoma cells by inhibiting MMP1 and MMP2 expression through downregulation of Rac1-ROS signaling.

• Journal of Microbiology and Biotechnology
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• v.32 no.8
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• pp.1034-1040
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• 2022

Fas-associated death domain (FADD) is an adapter molecule that bridges the interaction between receptor-interacting protein 1 (RIP1) and aspartate-specific cysteine protease-8 (caspase-8). As the primary mediator of apoptotic cell death, caspase-8 has two N-terminal death-effector domains (DEDs) and it interacts with other proteins in the DED subfamily through several conserved residues. In the tumor necrosis receptor-1 (TNFR-1)-dependent signaling pathway, apoptosis is triggered by the caspase-8/FADD complex by stimulating receptor internalization. However, the molecular mechanism of complex formation by the DED proteins remains poorly understood. Here, we found that direct DED-DED interaction between FADD and caspase-8 and the structure-based mutations (Y8D/I128A, E12A/I128A, E12R/I128A, K39A/I128A, K39D/I128A, F122A/I128A, and L123A/I128A) of caspase-8 disrupted formation of the stable DED complex with FADD. Moreover, the monomeric crystal structure of the caspase-8 DEDs (F122A/I128A) was solved at 1.7 Å. This study will provide new insight into the interaction mechanism and structural characteristics between FADD and caspase-8 DED subfamily proteins.

• Journal of Life Science
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• v.30 no.6
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• pp.532-541
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• 2020

In this study, we describe the inhibition of adipocyte differentiation by the lactic acid bacteria (LAB) fermentation product of Chrysanthemum indicum L. (CI) extract to control obesity. Preparation of LAB-fermented products was performed to overcome the cytotoxicity of CI extract. During fermentation and 3T3-L1 cell line experiment, cytotoxicity was not induced in the CI fermentation products over 1 day in culture. Fermented materials from highly proliferative cultures were selected for treatment of 3T3-L1 cells and for comparison with unfermented control groups. Cell survival and undifferentiated cell populations were decreased differentiation population in all experimental groups compared with controls, as measured using fluorescence-activated cell sorting analysis. Akt pathway activity increased upon treatment with these fermented extracts in 3T3-L1 cells. Gli2 depleted at the protein level in association with adipocyte differentiation. LAB KCTC 3115- and 3109-fermented extract treatment caused controlled Gli2 protein accumulation. Moreover, KCTC 3115 and 3109 were found to reduce C/EBPα and FAS was depleted, whereas pACC was increased at the protein level upon treatment with the fermentation products of each of the four LAB used in this study. With Lactococcus lactis subsp. lactis KCTC 3115 fermentation, the regulation of adipose differentiation and hedgehog signaling were also suppressed, thereby inhibiting the differentiation of progenitor cells. The basis for the activation of hedgehog signaling may provide insights into the treatment of obesity and the inhibition of adipocyte differentiation.