• IMMUNE NETWORK
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• 제11권6호
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• pp.383-389
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• 2011

Background: EY-6 is one of the newly synthesized indoledione derivatives to induce tumor cell-specific cell death. In this study, we investigated the mechanism of immunological death induced by EY-6 at mouse colon cancer cell as well as at the normal immune cell represented by dendritic cell. Methods: C57BL/6 mouse syngeneic colon cancer cell MC38 was treated with EY-6, and analyzed by MTT for viability test, flow cytometry for confirming surface expressing molecules and ELISA for detection of cytokine secretion. Normal myeloid-dendritic cell (DC) was ex vivo cultured from bone marrow hematopoietic stem cells of C57BL/6 mice with GM-CSF and IL-4 to analyze the DC uptake of dead tumor cells and to observe the effect of EY-6 on the normal DC. Results: EY-6 killed the MC38 tumor cells in a dose dependent manner (25, 50 and $100{\mu}M$) with carleticulin induction. And EY-6 induced the secretion of IFN-${\gamma}$ but not of TNF-${\alpha}$ from the MC38 tumor cells. EY-6 did not kill the ex-vivo cultured DCs at the dose killing tumor cells and did slightly but not significantly induced the DC maturation. The OVA-specific cross-presentation ability of DC was not induced by chemical treatment (both MHC II and MHC I-restricted antigen presentation). Conclusion: Data indicate that the EY-6 induced tumor cell specific and immunological cell death by modulation of tumor cell phenotype and cytokine secretion favoring induction of specific immunity eliminating tumor cells.

• 동의생리병리학회지
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• 제19권3호
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• pp.647-655
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• 2005

This study demonstrated anti-oxidative and neuroprotective effects of Rhei Rhizoma. Anti-oxidative effects were studied on BV-2 microglia cells damaged by $H_2O_2$ and nitric oxide. Neuroprotective effects were studied by using oxygen/glucose deprivation of the organotypic hippocampal slice cultures. The results obtained are as follows; The groups treated with 0.5 and 5 mg/ml of Puerariae Radix revealed significant decreases of neuronal cell death area and cell death area percentages in CA1 region of ischemic damaged hippocampus cultures during whole 48 hours of the experiment. The group treated with 50 mg/ml of Puerariae Radix demonstrated decreases of neuronal cell death area and cell death area percentages in CA1 region, but these were not significant statistically. The groups treated with 0.5 and 5 mg/ml of Puerariae Radix revealed significant decreases of neuronal cell death area and cell death area percentages in dentate gyrus of ischemic damaged hippocampus cultures during whole 48 hours of the experiment. The group treated with 50 mg/ml of Puerariae Radix demonstrated decreases of neuronal cell death area and cell death area percentages in dentate gyrus, but these were not significant statistically. The groups treated with 0.5 and 5 mg/ml of Puerariae Radix revealed significant decreases of TUNEL-positive cells in both CA1 region and dentate gyrus of ischemic damaged hippocampus cultures. The group treated with 50 mg/ml of Puerariae Radix demonstrated significant decrease of TUNEL-positive cells in CA1 region, but not in dentate gyrus of ischemic damaged hippocampus. The groups treated with 0.5 and 5 mg/ml of Puerariae Radix revealed significant decreases of LDH concentrations in culture media of ischemic damaged hippocampus cultures. The group treated with 50 mg/ml of Puerariae Radix demonstrated decrease of LDH concentrations in culture media, but it was not significant statistically. The groups treated with 0.5 and 5 mg/ml of Puerariae Radix revealed significant increases of cell viabilities of BV-2 microglia cells damaged by $H_2O_2$. The group treated with 50 mg/ml of Puerariae Radix demonstrated increase of cell viability of BV-2 microglia cells, but it was not significant statistically. The group treated with 0.5 mg/ml of Puerariae Radix revealed significant increase of cell viability of BV-2 microglia cells damaged by nitric oxide. The groups treated with 5 and 50 mg/ml of Puerariae Radix demonstrated increases of cell viabilities of BV-2 microglia cells, but these were not significant statistically. These results suggested that Puerariae Radix revealed neuroprotective effects through the control effect of apoptosis and oxidative damages.

• 대한한의학방제학회지
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• 제25권3호
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• pp.349-362
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• 2017

Objectives : We investigated whether the components of Ailanthus altissima induced apoptotic cell death in Jurkat acute lymphoblastic leukemia (ALL) cells. Methods : Regulation of cell proliferation is a complex process involving the regulated expression and/or modification of discrete gene products, which control transition between different stages of the cell cycle. Results : Upon treatments with Ailanthus altissima, the concentration-dependent inhibitions of cell viability were observed as compared to untreated control group. The capability of Ailanthus altissima to induce apoptosis was associated with proteolytic cleavage of specific target proteins such as poly(ADP-ribose)polymerase (PARP) and beta-catenin proteins suggesting the possible involvement of caspases. Ailanthus altissima also caused apoptosis as measured by cell morphology and DNA fragmentation. Conclusions : These results indicate that the increase of apoptotic cell death by Ailanthus altissima may be due to the inhibition of cell cycle in human Jurkat lymphocytes. Conclusively, these current and further findings will provide novel approaches to understanding and treating major diseases.

• BMB Reports
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• 제37권4호
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• pp.445-453
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• 2004

We identified apoptosis as being a significant mechanism of toxicity following the exposure of HeLa cell cultures to abrin holotoxin, which is in addition to its inhibition of protein biosynthesis by N-glycosidase activity. The treatment of HeLa cell cultures with abrin resulted in apoptotic cell death, as characterized by morphological and biochemical changes, i.e., cell shrinkage, internucleosomal DNA fragmentation, the occurrence of hypodiploid DNA, chromatin condensation, nuclear breakdown, DNA single strand breaks by TUNEL assay, and phosphatidylserine (PS) externalization. This apoptotic cell death was accompanied by caspase-9 and caspase-3 activation, as indicated by the cleavage of caspase substrates, which was preceded by mitochondrial cytochrome c release. The broad-spectrum caspase inhibitor, benzyloxycarbonyl-Val-Ala-Asp-fluoromethyl ketone (zVAD-fmk), prevented abrin-triggered caspase activation and partially abolished apoptotic cell death, but did not affect mitochondrial cytochrome c release. These results suggest that the release of mitochondrial cytochrome c, and the sequential caspase-9 and caspase-3 activations are important events in the signal transduction pathway of abrin-induced apoptotic cell death in the HeLa cell line.

• 동의생리병리학회지
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• 제18권1호
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• pp.236-242
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• 2004

Cerebral ischemia resulting from transient or permanent occlusion of cerebral arteries leads to neuronal cell death and eventually causes neurological impairments. Bee venom has been used for the treatment inflammatory disease. In the present study, the effects of bee venom on apoptosis and cell proliferation in the hippocampal dentate gyrus following transient global ischemia in gerbils were investigated using immunohistochemistry for cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2), caspase-3, and 5-bromo-2'-deoxyuridine (BrdU). It was shown that apoptotic cell death and cell proliferation in the hippocampal dentate gyrus were significantly increased following transient global ischemia in gerbils and that treatment of bee venom suppressed the ischemia-induced increase in apoptosis and cell proliferation in the dentate gyrus. The present results also showed that 1 mg/kg bee-venom treatment suppressed the ischemia-induced increasing apoptosis, cell proliferation, and COX-2 expression in the dentate gyrus. It is possible that the suppression of cell proliferation is due to the reduction of apoptotic cell death by treatment of bee venom. In the present study, bee venom was shown to prosses anti-apoptotic effect in ischemic brain disease, and this protective effect of bee venom against ischemia-induced neuronal cell death is closely associated with suppression on caspase-3 expression.

• The Korean Journal of Physiology and Pharmacology
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• 제22권6호
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• pp.689-696
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• 2018

Increasing evidence implicates changes in $[Ca^{2+}]_i$ and oxidative stress as causative factors in amyloid beta ($A{\beta}$)-induced neuronal cell death. Cyanidin-3-glucoside (C3G), a component of anthocyanin, has been reported to protect against glutamate-induced neuronal cell death by inhibiting $Ca^{2+}$ and $Zn^{2+}$ signaling. The present study aimed to determine whether C3G exerts a protective effect against $A{\beta}_{25-35}$-induced neuronal cell death in cultured rat hippocampal neurons from embryonic day 17 fetal Sprague-Dawley rats using MTT assay for cell survival, and caspase-3 assay and digital imaging methods for $Ca^{2+}$, $Zn^{2+}$, MMP and ROS. Treatment with $A{\beta}_{25-35}$ ($20{\mu}M$) for 48 h induced neuronal cell death in cultured rat pure hippocampal neurons. Treatment with C3G for 48 h significantly increased cell survival. Pretreatment with C3G for 30 min significantly inhibited $A{\beta}_{25-35}$-induced $[Zn^{2+}]_i$ increases as well as $[Ca^{2+}]_i$ increases in the cultured rat hippocampal neurons. C3G also significantly inhibited $A{\beta}_{25-35}$-induced mitochondrial depolarization. C3G also blocked the $A{\beta}_{25-35}$-induced formation of ROS. In addition, C3G significantly inhibited the $A{\beta}_{25-35}$-induced activation of caspase-3. These results suggest that cyanidin-3-glucoside protects against amyloid ${\beta}$-induced neuronal cell death by reducing multiple apoptotic signals.

• Annals of Clinical Neurophysiology
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• 제8권1호
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• pp.63-70
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• 2006

Background: Testosterone is reported to have neuroprotective effect in various neurological diseases. Recently, the mechanism involved in nitric oxide (NO)-mediated motor neuron death is under extensive investigation. The Cu/Zn-superoxide dismutase (SOD1) mutations has been implicated in selective motor neuron death of amyotrophic lateral sclerosis (ALS) and it is said to play an important role in NO-mediated motor neuron death. However, neuroprotective effect of testosterone on motor neuron exposed to NO has rarely been studied. Methods: Motor neuron-neuroblastoma hybrid cells expressing wild-type or mutant (G93A or A4V) SOD gene were treated with $200{\mu}M$ S-nitrosoglutathione. After 24 hr, cell viability was measured by MTT assay. To see the neuroprotective effect of testosterone, pretreatment with 1 nM testosterone was done 1 hr before S-nitroglutathione treatment. To study the mechanism of protective effect, $20{\mu}M$ flutamide (androgen receptor antagonist) was also pretreated with testosterone 1 hr before S-nitroglutathione treatment. Results: S-nitrosoglutathione showed significant neurotoxic effect in all three cell lines. Percentage of cell death was somewhat different in each cell line. 1 nM testosterone showed neuroprotective effect in G93A and wild-type cell line. In A4V cell line, testosterone did not showed neuroprotective effect. The neuroprotective effect of testosterone was reversed by $20{\mu}M$ flutamide. Conclusions: These results indicate that testosterone induces neuroprotection in NO-mediated motor neuron death directly through the androgen receptor. This neuroprotective effect of testosterone varies according to the types of SOD1 gene mutation. These data suggest that testosterone may be of therapeutic value against ALS.

• BMB Reports
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• 제37권2호
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• pp.185-191
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• 2004

Tissue transglutaminase (tTGase) regulates various biological processes, including extracellular matrix organization, cellular differentiation, and apoptosis. Here we report the protective role of tTGase in the cell death that is induced by the tumor necrosis factor $\alpha$ (TNF-$\alpha$) and ceramide, a product of the TNF-$\alpha$ signaling pathway, in human neuroblastoma SH-SY5Y cells. Treatment with retinoic acid (RA) induced the differentiation of the neuroblastoma cells with the formation of extended neurites. Immunostaining and Western blot analysis showed the tTGase expression by RA treatment. TNF-$\alpha$ or $C_2$ ceramide, a cell permeable ceramide analog, induced cell death in normal cells, but cell death was largely inhibited by the RA treatment. The inhibition of tTGase by the tTGase inhibitors, monodansylcadaverine and cystamine, eliminated the protective role of RA-treatment in the cell death that is caused by TNF-$\alpha$ or $C_2$-ceramide. In addition, the co-treatment of TNF-$\alpha$ and cycloheximide ecreased the protein level of tTGase and cell viability in the RA-treated cells, supporting the role of tTGase in the protection of cell death. DNA fragmentation was also induced by the co-treatment of TNF-$\alpha$ and cycloheximide. These results suggest that tTGase expressed by RA treatment plays an important role in the protection of cell death caused by TNF-$\alpha$ and ceramide.

• 대한한의학회지
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• 제29권1호
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• pp.95-105
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• 2008

Objectives : Although herbal medicines containing flavonoids have been reported to exert anti-tumor activities, it has not been explored whether Hwang-Jeong (Polygonati sibirici Rhizoma, PsR) exerts anti-tumor activity in human glioma. The present study was therefore undertaken to examine the effect of PsR on cell viability and to determine its underlying mechanism in A172 human glioma cells. Methods : Cell viability was estimated by MTT assay. Reactive oxygen species generation and mitochondrial membrane potential were measured by the fluorescence dyes. The phosphorylation of kinases was evaluated by western blot analysis and caspase activity was estimated using colorimetric assay kit. Results : PsR resulted in loss of cell viability in a dose- and time-dependent manner. PsR did not increase reactive oxygen species (ROS) generation and the PsR-induced cell death was also not affected by antioxidants, suggesting that ROS generation is not involved in loss of cell viability. Western blot analysis showed that PsR treatment caused rapid reduction in phosphorylation of extracellular signal-regulated kinase (ERK) without changes in p38 and Jun-NH2-terminal kinase (JNK). U0126, an inhibitor of ERK, increased the PsR-induced cell death, but inhibitors of p38 and JNK did not affect the cell death. PsR induced depolarization of mitochondrial membrane potential. Caspase activity was not stimulated by PsR and caspase inhibitors did not prevent the PsR-induced cell death. Conclusion : Taken together, these findings suggest that PsR results in human glioma cell death through caspaseindependent mechanisms involving down-regulation of ERK.

• Journal of Photoscience
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• 제9권2호
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• pp.509-511
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• 2002

In this study, we investigated apoptotic cell death induced by photodynamic therapy using 5-aminolaevulinic acid (ALA-PDT) in human promyelocytic leukemia cells (HL-60). ALA-PDT induced apoptosis in HL-60 cells as confirmed by DNA agarose gel electrophoresis and nuclear staining with Hoechst 33342. The apoptotic cell death was inhibited by addition of broad-spectrum caspase inhibitor Z-Asp-CH$_2$-DCB, indicating that the apoptotic cell death was induced in a caspase-dependent manner. Actually, western blotting analysis revealed that caspase-3 was processed as early as 1.5 h after ALA-PDT. Cytoplasmic cytochrome c released from mitochondria was detected by western blotting. However, inhibitor of caspase-9, a cysteine protease located in the downstream of cytochrome c release, was not able to reduce the apoptotic cell death. Therefore, the mitochondrial apoptotic pathway was not involved in the ALA-PDT-induced apoptosis. On the other hand, it was found that ALA-PDT-induced apoptosis was clearly inhibited by pretreatment of caspase-8 inhibitor. These data suggest that caspase-8-mediated apoptotic pathway is important in ALA-PDT-induced cell death.