• The Journal of Korean Medicine
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• v.21 no.4
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• pp.64-72
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• 2000

Objectives : This study was designed to investigate the neuroprotective effect of Hwansodan(Huanshao-dan) on the apoptosis induced by withdrawal of neurotrophic support. Methods : PCl2 pheochromocytoma cells have been used extensively as a model for studying the cellular and molecular effects of neuronal cells. The viability of cells was measured by MTT assay. We used DNA fragmentation and caspase 3-like protease activation assay. Results : The water extract of Hwansodan(Huanshao-dan) significantly showed protective effects on serum and glucose deprivation-induced apoptotic death. Hwansodan(Huanshao-dan) also prevents DNA fragmentation and caspase 3-like protease activation, representing typical neuronal apoptotic phenomena in PCl2 pheochromocytoma cells and induces tyrosine phosphorylation of proteins around 44 kDa, which was identified as ERK1 with electrophoretic gel mobility shift by Western blot. In addition, MAPK kinase(MEK) inhibitor PD98059 and Ras inactivator, ${\alpha}-hydroxyfarnesylphosphonic$ acid attenuated the neuroprotective effects of Hwansodan(Huanshao-dan) in serum-deprived PCl2 cells. Conclusions : These results indicate that Ras/MEK/ERK signaling pathway plays a key role in neuroprotective effects of Hwansodan(Huanshao-dan) in serum-deprived PCl2 cells. Taken together, we suggest the possibility that Hwansodan(Huanshao-dan) might provide a neurotrophic-like activity in PCl2 cells.

• Development and Reproduction
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• v.26 no.2
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• pp.79-90
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• 2022

Krüppel-like factor 10 (KLF10) regulates various cellular functions, such as proliferation, differentiation and apoptosis, as well as the homeostasis of several types of tissue. In the present study, we attempted a loss-of-function analysis of zebrafish Klf11a and Klf11b, which constitute human KLF10 homologs. Embryos injected with klf11b-morpholino (MO) showed developmental retardation and cell death, whereas klf11a-MO-injected embryos showed normal development. In klf11b-MO-injected embryos, a dramatic increase in the amount of zebrafish p53 mRNA might be the cause of the increase in that of bax. The degree of apoptosis decreased in the klf11b-MO and p53-MO co-injected embryos. These findings imply that KLF10 is a negative regulator of p53-dependent transcription, suggesting that the KLF10/p53 complex may play an important role in apoptosis for maintenance of tissue homeostasis during embryonic development.

• Molecules and Cells
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• v.38 no.2
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• pp.145-150
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• 2015

Continuous intra- and extracellular stresses induce disorder of $Ca^{2+}$ homeostasis and accumulation of unfolded protein in the endoplasmic reticulum (ER), which results in ER stress. Severe long-term ER stress triggers apoptosis signaling pathways, resulting in cell death. Neural epidermal growth factor-like like protein 2 (NELL2) has been reported to be important in protection of cells from cell death-inducing environments. In this study, we investigated the cytoprotective effect of NELL2 in the context of ER stress induced by thapsigargin, a strong ER stress inducer, in Cos7 cells. Overexpression of NELL2 prevented ER stress-mediated apoptosis by decreasing expression of ER stress-induced C/EBP homologous protein (CHOP) and increasing ER chaperones. In this context, expression of anti-apoptotic Bcl-xL was increased by NELL2, whereas NELL2 decreased expression of pro-apoptotic proteins, such as cleaved caspases 3 and 7. This anti-apoptotic effect of NELL2 is likely mediated by extracellular signal-regulated kinase (ERK) signaling, because its inhibitor, U0126, inhibited effects of NELL2 on the expression of anti- and pro-apoptotic proteins and on the protection from ER stress-induced cell death.

• Journal of Korean Medicine Rehabilitation
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• v.19 no.2
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• pp.103-112
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• 2009

Objectives : This study was to evaluate the pharmacological effect of Korea Red Ginseng aqueous extract (KRGE) on serum-deprived apoptosis of neuronal-like pheochromocytoma PC12 cells and to investigate its underlying action mechanism. Methods : KRGE was prepared by extracting Korea Red Ginseng with hot water and concentrating using a vacuum evaporator. Cell viability was determined after incubation of cells with KRGE or chemical inhibitor in serum-deprived medium for 60 h by counting intact nuclei following lysing of the cell membrane. Caspase activities were measured using chromogenic substrates and signal-associated protein phosphorylation and cytochrome c release were determined by Western blot analyses using their specific antibodies. Results : Serum deprivation induced PC12 cell death, which was accompanied by typical morphological features of apoptotic cell, such as nuclear fragmentation, caspase-3 activation, and cytochrome c release. This apoptotic cell death was significantly inhibited by KRGE and caspase-3 inhibitor, but not by the addition of NMA, ODQ, and PD98059. KRGE promoted phosphorylation of Akt and Bad, and this phosphorylation was inhibited by the PI3K inhibitor LY92004. In addition, this inhibitor also reversed KRGE-mediated protection of PC 12 cells from serum deprivation. These results suggested that KRGE protects PC12 cells from serum deprivation-induced apoptosis through the activation of PI3K/Akt-dependent Bad phosphorylation and cytochrome c release, resulting in caspase-3 activation. Conclusions : KRGE should be considered as a potential therapeutic drug for brain diseases including stroke induced by apoptosis of neuronal cells.

• Journal of Oriental Neuropsychiatry
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• v.10 no.2
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• pp.47-57
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• 1999

Recently, essential oils are used for aromatherapy. Most essential oils are said to be anti-bacterial; some may be anti-viral or anti-fungal. I investigated the effects of peppermint pure essential oil on the heat shock-induced apoptosis in human astrocyte cell line CCF-STTGI. In previous studies, heat shock has been reported to induce the apoptosis or programmed cell death through the activation of caspase-3. We studied the heat shock-induced apoptosis through flow cytometry, DNA electrophoresis, and giemsa staining. Interestingly, these events were inhibited by pretreatment of peppermint pure essential oils in CCF-STTGl cells. Peppermint oil also inhibited the heat shock-induced apoptosis in primary cultured rat astrocytes. In addition, this Peppermint essential oil inhibited the heat shock-induced activation of caspase-3. These results suggest that peppermint pure essential oils may modulate the apoptosis through the activation of the interleukin-I -converting enzyme-like protease.

• BMB Reports
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• v.44 no.9
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• pp.584-589
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• 2011

The mammalian ste20-like kinase (MST) pathway is important in the regulation of apoptosis and cell cycle and emerges as a novel tumor suppressor pathway. MST-induced phosphorylation of Salvador homolog 1 (SAV1), which is a scaffold protein, has not been evaluated in detail. We performed a mass spectrometric analysis of the SAV1 protein that was co-expressed with MST2. Phosphorylation was detected at Thr-26, Ser-27, Ser-36 and Ser-269. Although single or double mutations had little effects, the mutation of all four residues in SAV1 to Ala (SAV1-4A) had inhibitory effects on the MST pathway. MST2-mediated induction of SAV1-4A protein levels, SAV1-4A interaction with MST2 and the self-dimerization of SAV1-4A were weaker compared to those of wild-type SAV1. SAV1-4A inhibited MST2- and K-RasG12V-induced cell death of MCF7 cells. These results suggest that MST-mediated phosphorylation of four residues within SAV1 may be important in the induction of cell death by the MST pathway.

• Korean Journal of Veterinary Pathology
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• v.2 no.1
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• pp.37-46
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• 1998

It has been known that $\gamma$-irradiation usually induces cell death in regenerating stem cell in normal tissues like skin, intestine and hematopoietic organ. The experiment were carried out to evaluate the early response of radiation injury in radiosensitive and intermediate radiosensitive tissues in feeding and starving rats with the doses of 3.5 and 7.0 Gy. The results of the study showed that the histological phenomenon was apoptosis in the doses of the radiation as the early response of tissue injury. Apoptosis were showed organ-specific and cellular specific responses suggesting that the selection of apoptosis be exactly focused on highly renewal organs and cells. It was interesting that the rats starved for 72 hours prior to irradiation induced less apoptosis in liver than fed rats. As for cellular responses it appeared that apoptotic cells were mostly distributed in ductal or periportal cells in liver of feeding rats unlikely in liver of Starving rots which showed no difference in zonal distribution. In salivary gland apoptotic cells in fed rats were highly induced in intercalating and ductal cell population than in acinar cell population although unlikely in starved rats. This study showed the value of apoptosis using the detection system of TUNEL for evaluating cellular damage after radiation injury and the diminished effect of starvation on cell damage after ionizing irradiation.

• Animal cells and systems
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• v.5 no.2
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• pp.145-151
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• 2001

p62 is a phosphotyrosine-independent ligand of the SH2 domain of $p56^{Ick}$, a T-cell specific Src family tyrosine kinase. Recently p62 has been shown to interact with a number of proteins, such as $PKC\varsigma$ and ubiquitin, and implicated in important cellular functions such as cell proliferation. Since the two p62 interacting proteins, $p56^{Ick}$ and $PKC\varsigma$, have been reported to play roles in cell death, 1 have addressed the potential role of p62 during apoptosis in Jurkat cells in this study. Herein 1 show that p62 was specifically cleaved into two peptides by a caspase-3-like activity during Fas-receptor mediated apoptosis in Jurkat cells. This cleavage generated two fragments with molecular weights of about 35 kDa that differed in subcellular localizations. The N-terminal cleaved fragment was present in the detergent-insoluble fraction whereas the C-terminal fragment was found in the detergent-soluble fraction. In addition, the C-terminal fragment appeared to be subjected to further degradation as apoptosis prolonged. Moreover, overexpression of p62 in Jurkat cells attenuated the Fas receptor mediated apoptosis, suggesting that p62 is involved in apoptotic signal transduction pathway in lymphocytes.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2003.10a
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• pp.176-176
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• 2003

Methylmercury is known to have devastating effects on the mammalian nervous system. When human neuroblastoma SH-SY5Y cells were treated with methylmercury at sublethal concentrations (6.25 uM), up-regulated genes (39) ＆ down-regulated genes (19) were identified by human 8k cDNA microarray. These genes are related with microtubule process, signal transduction pathway and cell death (apoptosis), Apoptosis-associated genes, HSP70, CDK inhibitor 1, FOS-like antigen were up-regulated and microtubule related genes like villin and dynein down-regultaed. To confirm the presence of apoptosis in cultured SH-SY5Y cells treated 6.25 and 1 uM methylmercury, we applied Annexin V-FITC assay followed by flow cytometric measurements after 6 and 24h. Studies on transcriptional and molecular effect by methylmercury may provide an insight into the neurotoxic effects of methylmercury in human neuronal cells and a possibility to develop more efficient and exact monitoring system of heavy metals as ubiquitous environmental pollutants.

• Journal of Life Science
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• v.26 no.4
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• pp.431-438
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• 2016

The tumour necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is considered a promising anticancer agent due to its unique ability to induce cancer cell death having only negligible effects on normal cells. However, many cancer cells tend to be resistant to TRAIL. In this study, we investigated the effects and molecular mechanisms of sodium butyrate (SB), a histone deacetylase inhibitor, in sensitizing TRAIL-induced apoptosis in 5637 human bladder cancer cells. Our results indicated that co-treatment with SB and TRAIL significantly increased the apoptosis induction, compared with treatment with either agent alone. Co-treatment with SB and TRAIL effectively increased the cell-surface expression of death receptor (DR) 5, but not DR4, which was associated with the inhibition of cellular Fas-associated death domain (FADD)-like interleukin-1β-converting enzyme (FLICE) inhibitory protein (c-FLIP). Furthermore, the activation of caspases (caspase-3, -8 and -9) and degradation of poly(ADP-ribose) were markedly increased in 5637 cells co-treated with SB and TRAIL; however, the synergistic effect was perfectly attenuated by caspase inhibitors. We also found that combined treatment with SB and TRAIL effectively induced the expression of pro-apoptotic Bax, cytosolic cytochrome c and cleave Bid to truncated Bid (tBid), along with down-regulation of anti-apoptotic Bcl-xL expression. These results collectively suggest that a combined regimen of SB plus TRAIL may offer an effective therapeutic strategy for safely and selectively treating TRAIL-resistant bladder cancer cells.