• BMB Reports
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• v.32 no.4
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• pp.379-384
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• 1999

Taxol, a natural product with significant anti-tumor activity, stabilizes microtubules and arrests cells in the G2/M phase of the cell cycle. It has been reported that taxol has additional effects on the cell such as an increase in tyrosine phosphorylation of proteins and activation of mitogen-activated protein (MAP) kinase. This phosphorylated kinase translocates into the nucleus and phosphorylates its substrate c-jun, c-fos, ATF2, and ATF3. The MAP kinase family is comprised of key regulatory proteins that control the cellular response to both proliferation and stress signals. First examination was cytotoxicity and apoptosis-induced concentration with paclitaxel in HeLa cell. A half-maximal inhibition of cell proliferation ($IC_{50}$) occurred at 13 nM paclitaxel. When DNA fragmentation was analyzed by agarose gel electrophoresis, a nucleosomal ladder became evident 24 h after a taxol (50 nM) addition to the cells. In addition, an apoptotic body was detected by electron microscopy. Taxol-treated cells were arrested at the S phase at 10 nM. Treatment of 50 nM taxol activated the extracellular signal-regulated protein kinase (ERK1), and a fraction of the activated MAP kinases entered the nucleus. It was also discovered that nucleus substrates c-jun was phosphorylated and activated in the cell. The activated ERK1 could subsequently translocate into the nucleus and phosphorylate its substrate c-jun as well. This study suggests that taxol-induced apoptosis might be related with signal transduction via MAP kinases.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.4
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• pp.1120-1128
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• 2004

Zinc ion has both essential and toxic effects on mammalian cells. The results demonstrated that the ability of zinc to act as an inducer of apoptosis in C6 glial cells. Incubation with 0.2 mM ZnCl₂ caused cell death that was characterized as apoptosis by internucleosomal DNA fragmentation, formation of apoptotic bodies, nuclear fragmentation and breakdown of the mitochondrial membrane potential. ZnCl₂-induced apoptosis of C6 glial cells was prevented by the addition of Sibjeondaebo-Tang and antioxidants including reduced glutathione, N-acetyl-L-cysteine. We further confirmed that ZnCl₂ decreased the intracellular levels of GSH as well as generation of H₂O₂ in C6 glial cells. In 2D-electrophoresis, computer-assisted comparative analysis of the respective silver stained spot patterns revealed 3 groups with strongly decreased intensity by ZnCl₂. Whereas, 3 groups with increasing intensity were recovered by Sibjeondaebo-Tang. These results suggest that Sibjeondaebo-Tang may function as an antioxidant against free radicals and be applicable to the treatment of brain cells against oxidative stress.

• Journal of Life Science
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• v.8 no.1
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• pp.51-59
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• 1998

The apoptosis-inducing activity of ursolic acid (UA) was examined in mouse F9 teratocarcinoma cells on the bases of biochemical and morphological characteeristics. UA, pentacyclic trierpene acid, exhibits antitumor activities including inhibition of skin tumorigenesis, induction of tumor cell differentiation and antitumor promotion. Treatment with UA showed that the decrease of cell viability was dose-dependent. UA also induced genomic DNA fragmetation, a hallmark of apoptosis, indicating that the mechanism of UA-induced F9 cell death was through apoptosis. When the morphology of the F9 cells was examined by electron microscopy, the cells treated with UA showed the charcteristic morphological features of apoptosis such as chromatin condensation and nuclear fragmentation. DNA fragmentations by UA were inhibired by cycloheximide, which suggest that de novo protein synthesis was required for DNA fragmentation by UA. Inaddition, the expression of c-jun was increased, but those of c-myc and laminin B1 were decreased during apoptosis induced by UA in F9 cells. These results suggest that UA causes an apoptosis in F9 cells. Further, the increased expression of c-jun may be involved in the UA-induced apoptosis of f9 cells.

• Food Science and Biotechnology
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• v.16 no.4
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• pp.531-536
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• 2007

The aerial part of Artemisia iwayomogi Kitamura has traditionally been used for inflammation, infectious disease, cancer, pyretic, diuretic, liver protective effect, and choleretic purposes in Korea. We investigated that the essential oil induces apoptosis in KB cell as evidenced by Hoechst-33258 dye staining, flow cytometry (cell cycles), and DNA fragmentation for nuclear condensation and Western blotting for activation of caspases-3, -8, -9, Bax, Bcl-2, cytochrome c, and poly (ADP-ribose) polymerase (PARP) cleavage. In the present study, we found that the essential oil could induce apoptosis in KB cells, as characterized by DNA fragmentation, activation of caspase-3, -8, and -9, and PARP cleavage. The efficacious induction of apoptosis was observed as a dose-dependent. The essential oil-induced apoptotic cell death was accompanied by up-regulation of Bax and down-regulation of Bcl-2. The essential oil also caused the loss of mitochondrial membrane potential and cytochrome c release from mitochondria to cytosol. These findings indicate that mitochondrial pathways might be involved in the essential oil-induced apoptosis and enhance our understanding of the anticancer function of the essential oil in herbal medicine.

• Journal of the Korean Society of Food Culture
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• v.36 no.2
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• pp.235-245
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• 2021

Lindera glauca Blume has been used in Korean traditional medicine to treat the symptoms of paralysis, abdominal pain, speech disorders, extravasations, contusions, and pain caused by rheumatoid arthritis. We investigated the effect of L. glauca Blume extracts on the proliferation of colorectal cancer cells in vitro using HCT116 human colorectal cancer cell lines. We also investigated its mechanism of action. For this purpose, we used the MTT assay, western blotting, DNA fragmentation analysis, and flow cytometry. HCT116 cells were cultured in several concentrations of ethanol extracts of L. glauca Blume root (0, 50, 100 ㎍/mL). In this study, colon cancer cell growth was inhibited by L. glauca Blume root extract in a dose-dependent manner. It was associated with induction of apoptosis as assessed by nuclear fragmentation and cell cycle analysis. Apoptosis was assessed using western blotting for TNF-α, IL-6, NF-κB, Caspase-3, PARP, Bax, Bcl-2, and SIRT1. The extract also dose-dependently upregulated the expression Bax, the pro-apoptotic gene and downregulated the expression of the anti-apoptotic gene Bcl-2. Furthermore, the extract enhanced Caspase-3 activity in a dose-dependent manner. Our findings provide evidence that L. glauca Blume extract may mediate its anti-proliferative effect via the modulation of apoptosis.

• Journal of Embryo Transfer
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• v.10 no.1
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• pp.45-51
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• 1995

In order to determine the optimum condition and timing for in vitro maturation of oocytes to metaphase of meiosis II (M II), the immatured follicular oocytes were recovered by puncturing the large(1.0~1.5 mm in diameter) and small(<1.0 mm in diameter) follicles in the ovaries of rabbits treated intramuscularly with a single dose of 100 TU PMSG 68 hours previously. The follicular oocytes were classified into three grades by the attachment of cumulus cells. The Grade I and II follicular oocytes from large follicles were cultured in BO-DM medium with 10% FCS, 35 $\mu$g /nl of FSH, 10 $\mu$g /ml of LH and 1 $\mu$g /ml of estradiol-17$\beta$ at 39t in a 5% $CO_2$ incubator for 11 to 23 hours. In 3 hours interval during the culture period, the oocytes were harvested and their cumulus cells were removed with hyaluronidase. The denuded oocytes were stained with Hoechst 33342 dye and their meiotic status and extrusion of the first polar body (PB) were examined under a fluorescence microscope. Also the fragmentation of the first PB and the distance between the first PB and nucleus were examined. The results obtained were as follows: 1. The mean recovery rate of follicular oocytes from the large and small follicles was 59. 9 and 31.3%, respectively. The mean number of oocytes recovered per rabbit and the Grade I percentage were 14.6 and 94.4% in large follicles, but 2.1 and 61.1% in small follicles, respectively. All the parameters examined were different significantly (p<0.05) between both the folliclular size. 2. Most of the follicular oocytes(86.8%) were matured in vitro to M II phase in 14 hours in Grade I oocytes, but the significantly(p<0.05) less oocytes(45.5%) were matured in Grade II oocytes. 3. The first PB was extruded in most of the oocytes(94.7%) in 14 hours of culture with the fragmentation rate of 29.6%, but the fragmentation rate of the first PB increased significantly (p<0.05) as the culture period for maturation was longer to 20 hours(63.5%). 4. The distance between the first PB and nucleus was increased linearly (p<0.05) as the maturation time passed from 14(7.1$\mu$rn) to 23 hours(58.4$\mu$m). 5. From the above results it was concluded that the optimum time for in vitro maturation culture might be 14 hours in the follicular oocytes from rabbit primed with PMSG for 68 hours, expecially when these follicular oocytes were used for recipient cytoplasms in embryo cloning.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.16 no.4
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• pp.411-420
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• 2018

This study presents a revised crackling core model for the description of $UO_2$ sphere oxidation in air atmosphere. For close reproduction of the sigmoid behavior exhibited in $UO_2$ to $U_3O_8$ conversion, the fragmentation effect contributing to the increased reactive surface area and the concept of variable grain conversion time were considered in the model development. Under the assumptions of two-step successive reaction of $UO_2{\rightarrow}U_3O_7{\rightarrow}U_3O_8$ and final grain conversion time equivalent to ten times the initial grain conversion time, the revised model showed good agreement with the experimental data measured at 599 - 674 K and a lowest deviation when compared with Nucleation and Growth model and AutoCatalytic Reaction model. The evaluated activation energy at 100% conversion to $U_3O_8$, $57.6kJ{\cdot}mol^{-1}$, was found to be closer to the experimentally extrapolated value than to the value determined in AutoCatalytic Reaction model, $48.6kJ{\cdot}mol^{-1}$.

• Korean Journal of Animal Reproduction
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• v.18 no.3
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• pp.217-228
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• 1994

These experiments were carried out to establish the optimal condition of electrostimulatin inducing cell fusion and oocyte activation for nuclear transplantation in mouse embryos. Eggs selected for cell fusion or activation by electrostimulation were equilibrated for 5~10 min. in 0.3M sucrose solution and electrostimulated for 60$\mu$sec using 1 pulse of 60, 70, 80, 90 or 100 volts DC with electrodes 0.2 mm apart. Then they were cultured in 20${mu}ell$ dropsof Tyrode's solution. The results of these experiments are as follows : 1. When one pulse of 60, 70, 80, 90 or 100 volts DC for 60$\mu$sec were applied to 2-cell embryos for fusion of blastomeres, fusion rates were 50.0, 81.7, 91.7, 100 and 100%, respectively ; and developmental rates of fused embryos to blastocyst were 76.7 to 81.5%. Higher fusion rates were observed in 90V and 100V. 2. The average cell number in fused embryos developed to blastocyst was about half of the cell number in diploid controls; and the cell number decreased with increasing of voltages. 3. When pulse numbers were increased, fusion rates improved, but developmental rates were not signficiantly different from the group for which the number of pulse was not increased. And the cell number of blastocyst decreased even more. 4. Oocytes aged for 6hrs after ovulation were electrostimulated for oocyte activation by the same method used for cell fusion. Rates of oocyte activated by electrostimulation were 45.3 to 60.4%, and fragmentation rates were 7.5~15.1%. The lysis rates were 17.0~34.0%. The results of these experiments indicate that the optimal condition for achieving cell fusion and activation is 1 pulse, duration 60$\mu$sec in 90 Volt. The results also show that this condition is suitable for nuclear transplantation using mouse eggs.

• Clinical and Experimental Reproductive Medicine
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• v.50 no.3
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• pp.177-184
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• 2023

Objective: Reconstructed oocytes after polar body genome transfer constitute a potential therapeutic option for patients with a history of embryo fragmentation and advanced maternal age. However, the rescue of genetic material from the first polar body (PB1) through introduction into the donor cytoplasm is not yet ready for clinical application. Methods: Eighty-five oocytes were obtained following in vitro maturation (IVM) and divided into two groups: PB1 nuclear transfer (PB1NT; n=54) and control (n=31). Following enucleation and PB1 genomic transfer, PB1 fusion was assessed. Subsequently, all fused oocytes underwent intracytoplasmic sperm injection (ICSI) and were cultured in an incubator under a time-lapse monitoring system to evaluate fertilization, embryonic morphokinetic parameters, and cleavage patterns. Results: Following enucleation and fusion, 77.14% of oocytes survived, and 92.59% of polar bodies (PBs) fused. However, the normal fertilization rate was lower in the PB1NT group than in the control group (56.41% vs. 92%, p=0.002). No significant differences were observed in embryo kinetics between the groups, but a significant difference was detected in embryo developmental arrest after the four-cell stage, along with abnormal cleavage division in the PB1NT group. This was followed by significant between-group differences in the implantation potential rate and euploidy status. Most embryos in the PB1NT group had at least one abnormal cleavage division (93.3%, p=0.001). Conclusion: Fresh PB1NT oocytes successfully produced normal zygotes following PB fusion and ICSI in IVM oocytes. However, this was accompanied by low efficiency in developing into cleavage embryos, along with an increase in abnormal cleavage patterns.

• Journal of Life Science
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• v.21 no.5
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• pp.753-760
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• 2011

In the present study, the effects of paprika extract and its components including vitamin C, lycopene and beta-carotene on cell death in ultraviolet B (UVB)-exposed HaCaT cells were investigated. The cell viability upon treatment for 24 hr with either paprika extract or vitamin C alone was similar to or greater than that of the untreated control. However, the viability of the cells treated with lycopene or beta-carotene decreased to about 20% of that in the untreated control. When UVB-exposed cells were post-incubated for 24 hr in medium containing paprika extract or vitamin C, cell viability increased in a concentration dependent manner as compared to those post-incubated in a normal growth medium. In contrast, post-incubation of UVB-exposed cells with lycopene or beta-carotene decreased cell viability in a concentration dependent manner as compared to those post-incubated in a normal growth medium. The nuclear fragmentation analysis showed that paprika extract or vitamin C decreases UVB-induced apoptosis. The apoptotic nuclear fragmentation resulting from UVB exposure was also protected by the paprika extract or vitamin C post-incubation. However, the UVB-induced apoptotic nuclear fragmentation of the cells treated with lycopene or beta-carotene increased in a concentration dependent manner. Western blot analysis showed that either paprika extract or vitamin C treatment alone did not significantly change the level of p53 and GADD45 protein. Interestingly, post-incubation of UVB-exposed cells with paprika extract or vitamin C decreased the p53 and GADD45 protein level as compared to those post-incubated in a normal growth medium. In contrast, incubation of UVB-exposed or non-irradiated cells with lycopene or beta-carotene increased the p53 and GADD45 protein levels in a concentration dependent manner as compared to those incubated in a normal growth medium. All these results suggest that paprika extract and vitamin C help the survival of the UVB-exposed cells, while lycopene and beta-carotene potentiate the apoptotic death of UVB-exposed cells, in accordance with the respective changes in p53 and GADD45 protein levels.