• The Korean Journal of Physiology and Pharmacology
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• v.22 no.6
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• pp.617-625
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• 2018

Neddylation is a post-translational protein modification process. MLN4924 is a newly discovered pharmaceutical neddylation inhibitor that suppresses cancer growth with several cancer types. In our study, we first investigated the effect of MLN4924 on colon cancer cells (HCT116 and HT29). MLN4924 significantly inhibited the neddylation of cullin-1 and colon cancer cell growth in a time and dose-dependent manner. MLN4924 induced G2/M cell cycle arrest and apoptosis in HCT116 and HT29 cells. Moreover, MLN4924 also triggered autophagy in HCT116 and HT29 cells via suppressing the PI3K/AKT/mTOR pathway. Inhibiting autophagy by autophagy inhibitor 3-MA or ATG5 knockdown reversed the function of MLN4924 in suppressing colon cancer cell growth and cell death. Interestingly, MLN4924 suppresses colon cell growth in a xenograft model. Together, our finding revealed that blocking neddylation is an attractive colon cancer therapy strategy, and autophagy might act as a novel anti-cancer mechanism for the treatment of colon cancer by MLN4924.

• Journal of Ginseng Research
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• v.22 no.3
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• pp.216-221
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• 1998

We examined the anti-invasive activity of ginsenosides Rhl, Rha on the highly metastatic HT1080 human fibrosarcoma cell line. In vitro invasion assay showed ginsenoside Rhr reduced tumor cell invasion through a reconstituted basement membrane in a transwell chamber more than ginsenoside Rh1. Significant down-regulation of matrix metalloproteinase-9 (MMP-9) by ginsenosides Rh, and Rh2 was detected by Northern blot analysis. However, the expression of MMP-2 was not affected by Rh, and Rhr. The expression of tissue inhibitor of metalloproteinase-2 (TIMP-2) was increased by Rhl after 0.5, 1 or 3 day-treatment but reduced after 6 day-treatment. However, the expression of TIMP-2 was not changed by treatment with Rh2. Plasminogen activator inhibitor (PAI) and urokinase-type plasmlnogen activator (uPA) were not changed by treatment with Rh1 and Rh2 for 3 and 6 days. Quantitative gelatin-based zymography confirmed a markedly reduced expression of MMP-9 but MMP-2 after treatments with ginsenosides Rhl and Rha. These results suggest that down-regulation of MMP-9 contributes to the anti-invasive activity of ginsenosides Rhl and Rhr in the HT1080 cells.

• Korean Journal of Pharmacognosy
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• v.42 no.2
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• pp.175-181
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• 2011

Oxidative stress or accumulation of reactive oxygen species (ROS) leads neuronal cellular death and dysfunction, and it contributes to neuronal degenerative disease such as Alzheimer's disease, Parkinson's disease and stroke. Glutamate is one of the major excitatory neurotransmitter in the central nervous system (CNS). Glutamate contributes to fast synaptic transmission, neuronal plasticity, outgrowth and survival, behavior, learning and memory. In spite of these physiological functions, high concentration of glutamate causes neuronal cell damage, acute insults and chronic neuronal neurodegenerative diseases. Heme oxygenase-1 (HO-1) enzyme plays an important role of cellular antioxidant system against oxidant injury. NNMBS020, the water-insoluble fraction of the 70% EtOH extract of root barks of Dictamnus dasycarpus, showed dominant neuroprotective effects on glutamate-induced neurotoxicity in mouse hippocampal HT22 cells by induced the expression of HO-1 and increased HO activity. In mouse hippocampal HT22 cells, NNMBS020 makes the nuclear accumulation of Nrf2 and stimulates extracellular signal-regulated kinase (ERK) pathway. The ERK MAPK pathway inhibitor significantly reduced NNMBS020-induced HO-1 expression, whereas the JNK and p38 inhibitors did not. In conclusion, the water-insoluble fraction of the 70% EtOH extract of root barks of D. dasycarpus (NNMBS020) significantly protect glutamate-induced oxidative damage by induction of HO-1 via Nrf2 and ERK pathway in mouse hippocampal HT22 cells.

• Journal of electromagnetic engineering and science
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• v.15 no.3
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• pp.123-128
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• 2015

Previously, we investigated extremely low-frequency magnetic fields (ELF-MFs) on diverse DNA damage responses, such as phosphorylated H2AX (${\gamma}H2AX$), comet tail moments, and aneuploidy production in several non-tumorigenic epithelial or fibroblast cell lines. However, the effect of ELF-MF on DNA damage responses in neuronal cells may not be well evaluated. Here, we investigated the effects of ELF-MF on the DNA damage responses in HT22 non-tumorigenic mouse neuronal cells. Exposure to a 60-Hz, 2 mT ELF-MF did not produce any increased ${\gamma}H2AX$ expression, comet tail moments, or aneuploidy formation. However, 2 mT ELF-MF transiently increased the cell number. From the results, ELF-MF could affect the DNA damage responses differently, depending on the cell lines.

• Herbal Formula Science
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• v.22 no.2
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• pp.35-43
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• 2014

Objectives : The purpose of this study was to identify antiproliferative effects of Salviae miltiorrhizae Radix(SM) extracts against cancer cell lines. Methods : We used 2 kinds of cancer cell lines such as colon cancer cells(HT-29), human oral epitheloid carcinoma cells(KB). MTT assay was performed to examine the efficacy of SM extracts on the cytostaticity of cancer cells in proportion to time and doses. Apoptosis was evaluated by DNA laddering and DAPI nuclei staining. Results : The MTT absorbances against HT-29 and KB of SM extracts were significantly decresed. DNA ladders could be identified in KB of SM extracts. The morphological change were observed and number of cells were decreased by SM extracts. Conclusions : SM extracts is considered to be effective to induce apoptosis and inhibit cancer cell proliferation.

• BMB Reports
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• v.49 no.11
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• pp.617-622
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• 2016

Oxidative stress is closely associated with various diseases and is considered to be a major factor in ischemia. NAD(P)H: quinone oxidoreductase 1 (NQO1) protein is a known antioxidant protein that plays a protective role in various cells against oxidative stress. We therefore investigated the effects of cell permeable Tat-NQO1 protein on hippocampal HT-22 cells, and in an animal ischemia model. The Tat-NQO1 protein transduced into HT-22 cells, and significantly inhibited against hydrogen peroxide ($H_2O_2$)-induced cell death and cellular toxicities. Tat-NQO1 protein inhibited the Akt and mitogen activated protein kinases (MAPK) activation as well as caspase-3 expression levels, in $H_2O_2$ exposed HT-22 cells. Moreover, Tat-NQO1 protein transduced into the CA1 region of the hippocampus of the animal brain and drastically protected against ischemic injury. Our results indicate that Tat-NQO1 protein exerts protection against neuronal cell death induced by oxidative stress, suggesting that Tat-NQO1 protein may potentially provide a therapeutic agent for neuronal diseases.

• Journal of Korean Neurosurgical Society
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• v.46 no.4
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• pp.389-396
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• 2009

Objective : Triptolide (TP) has been reported to suppress the expression of mitogen-activated protein kinase (MAPK) phosphatase-1 (MKP-1), of which main function is to inactivate the extracellular signal-regulated kinase-1/2 (ERK-1/2), the p38 MAPK and the c-Jun N-terminal kinase-1/2 (JNK-1/2), and to exert antiproliferative and pro-apoptotic activities. However, the mechanisms underlying antiproliferative and pro-apoptotic activities of TP are not fully understood. The purpose of this study was to examine whether the down-regulation of MKP-1 expression by TP would account for antiproliferative activity of TP in immortalized HT22 hippocampal cells. Methods : MKP-1 expression and MAPK phosphorylation were analyzed by Western blot. Cell proliferation was assessed by $^3H$-thymidine incorporation. Small interfering RNA (siRNA) against MKP-1, vanadate (a phosphatase inhibitor), U0126 (a specific inhibitor for ERK-1/2), SB203580 (a specific inhibitor for p38 MAPK), and SP600125 (a specific inhibitor for JNK-1/2) were employed to evaluate a possible mechanism of antiproliferative action of TP. Results : At its non-cytotoxic dose, TP suppressed MKP-1 expression, reduced cell growth, and induced persistent ERK-1/2 activation. Similar growth inhibition and ERK-1/2 activation were observed when MKP-1 expression was blocked by MKP-1 siRNA and its activity was inhibited by vanadate. The antiproliferative effects of TP, MKP-1 siRNA, and vanadate were significantly abolished by U0126, but not by SB203580 or SP600125. Conclusion : Our findings suggest that TP inhibits the growth of immortalized HT22 hippocampal cells via persistent ERK-1/2 activation by suppressing MKP-1 expression. Additionally, this study provides evidence supporting that MKP-1 may play an important role in regulation of neuronal cell growth.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.6
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• pp.1470-1474
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• 2008

This study was performed to examine the anti-metastatic effect of ethanol extract of Samguikoeui-Tang (SGKE), a formula consisting of four oriental herbs, in highly-metastatic HT1080 human fibrosarcoma cells. SGKE significantly inhibited the adhesion of HT1080 cells to matrigel at nontoxic concentrations in a dose-dependent manner, while it did not exert cytotoxicity against HT1080 cells up to the concentration of 100 ${\mu}g$/ml. Also, SGKE depressed the activity of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) by gelatin zymography. However, SGKE did not affect the mRNA expression of MMP-2 and TIMP-2, an inhibitor of MMP-2, by RT-PCR analysis. In addition, the effect of SGKE on HT1080 cell invasion was determined using Boyden chamber assay. SGKE suppressed the invasion of HT1080 cells in a dose-dependent manner. Taken together, these results suggest that SGKE has an anti-metastatic effect via inhibition of MMP-2 and -9 activities.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.5
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• pp.1334-1336
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• 2006

Effects of twenty-three aqueous herbal extracts used in oriental medicines on heme oxygenase (HO)-1 expression were estimated in a mouse hippocampal cell line, HT22. HO-1 is one of the cytoprotective enzymes activated various stimuli, and Western blot analysis was used for evaluated HO-1 expression. Six aqueous extracts such as Rhei Rhizoma, Paeoniae Radix, Uncariae Ramulus et Uncus, Theae Folium, Prunellae Spica, and Coptidis Rhizoma significantly increased HO-1 expression in HT22 cells at the concentration of 300 ${\mu}$g/ml. In Addition, four aqueous extracts including Eucommiae Cortex, Moutan Cortex Radicis, Ginseng Radix Rubra, and Scutellariae Radix moderately increased HO-1 expression. These results would be usefulfor the isolation and identification of their neuroprotective principles.

• Environmental Analysis Health and Toxicology
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• v.19 no.3
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• pp.279-286
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• 2004

Although numerous studies have shown that cadmium disturbs the normal biological processes in central nervous system, the mechanism of toxicity is not well understood. The present study has investigated the effect of cadmium on oxidative stress, Na$^{+}$K$^{+}$ ATPase activity and the aggregation of amyloid beta peptide ($\beta$-amyloid) in neuronal cell line, HT22 cell. LC$_{5}$ and LC$_{50}$ of cadmium for HT22 cell resulted from MTT assay was 4.1 uM and 9.5 uM, respectively. Cadmium (2 to 8 uM) dose-dependently increased the lipid peroxidation and decreased the content of glutathione. Cadmium 4 uM showed a significant decrease in Na$^{+}$/K $^{+}$ ATPase activity as compared with control group. The aggregation of $\beta$-amyloid was accelerated in a dose-dependent manner by the treatment with 2 to 8 uM cadmium. These results suggest that the neurotoxicity of cadmium can be mediated by the increase in oxidative stress and decrease in Na$^{+}$/K$^{+}$ ATPase activity.se activity.