• 한국축산식품학회지
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• 제30권5호
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• pp.804-810
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• 2010

This study was performed to select protease-producing Bacillus sp. as a potential probiotic starter for fermented meat products. In order to isolate protease-producing bacterium from meju, measured the diameter of the clear zone on agar plate (TSA, 1% (w/v) skim milk) and analyzed for intracellular protease activity, then 10 Bacillus-like strains were isolated. Three Bacillus-like strains (P19, P27, and P33) among 10 strains were able to tolerate in acidic condition (TSB, pH 2.5, 2 h incubation). These 3 strains were showed antimicrobial activity against food-borne pathogenic bacteria. These vegetative cells of 3 strains were showed a survival rate of 0.04% to 0.08% under the artificial gastric acidic condition (TSB, pH 2.5 with 1% (w/v) pepsin), but spore-forming cells were 56.29% to 84.77%. Vegetative cells of 3 strains were the least bile-resistant, while spore-forming cells of 3 strains showed higher survival rate more than 76% under artificial bile condition (TSB, 0.1% (w/v) oxgall bile). In these strains, P27 strain was finally selected as a good probiotic strain. P27 strain was tentatively identified as Bacillus amyloliquefaciens by API CHB kit and 16S rDNA sequence analysis. The results of this study suggest that B. amyloliquefaciens P27 can be used as a potential probiotic starter for fermented meat product.

• Parasites, Hosts and Diseases
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• 제51권3호
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• pp.279-287
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• 2013

Autophagy is a process of cytoplasmic degradation of endogenous proteins and organelles. Although its primary role is protective, it can also contribute to cell death. Recently, autophagy was found to play a role in the activation of host defense against intracellular pathogens. The aims of our study was to investigate whether host cell autophagy influences Toxoplasma gondii proliferation and whether autophagy inhibitors modulate cell survival. HeLa cells were infected with T. gondii with and without rapamycin treatment to induce autophagy. Lactate dehydrogenase assays showed that cell death was extensive at 36-48 hr after infection in cells treated with T. gondii with or without rapamycin. The autophagic markers, LC3 II and Beclin 1, were strongly expressed at 18-24 hr after exposure as shown by Western blotting and RT-PCR. However, the subsequent T. gondii proliferation suppressed autophagy at 36 hr post-infection. Pre-treatment with the autophagy inhibitor, 3-methyladenine (3-MA), down-regulated LC3 II and Beclin 1. The latter was also down-regulated by calpeptin, a calpain inhibitor. Monodansyl cadaverine (MDC) staining detected numerous autophagic vacuoles (AVs) at 18 hr post-infection. Ultrastructural observations showed T. gondii proliferation in parasitophorous vacuoles (PVs) coinciding with a decline in the numbers of AVs by 18 hr. FACS analysis failed to confirm the presence of cell apoptosis after exposure to T. gondii and rapamycin. We concluded that T. gondii proliferation may inhibit host cell autophagy and has an impact on cell survival.

• Molecules and Cells
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• 제42권12호
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• pp.869-883
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• 2019

Interleukin (IL)-15 is an essential immune-modulator with high potential for use in cancer treatment. Natural IL-15 has a low biological potency because of its short half-life and difficulties in mass-production. IL-15Rα, a member of the IL-15 receptor complex, is famous for its high affinity to IL-15 and its ability to lengthen the half-life of IL-15. We have double-transfected IL-15 and its truncated receptor IL-15Rα into CT26 colon cancer cells to target them for intracellular assembly. The secreted IL-15:IL-15Rα complexes were confirmed in ELISA and Co-IP experiments. IL-15:IL-15Rα secreting clones showed a higher anti-tumor effect than IL-15 secreting clones. Furthermore, we also evaluated the vaccine and therapeutic efficacy of the whole cancer-cell vaccine using mitomycin C (MMC)-treated IL-15:IL-15Rα secreting CT26 clones. Three sets of experiments were evaluated; (1) therapeutics, (2) vaccination, and (3) long-term protection. Wild-type CT26-bearing mice treated with a single dose of MMC-inactivated secreted IL-15:IL-15Rα clones prolonged survival compared to the control group. Survival of MMC-inactivated IL-15:IL-15Rα clone-vaccinated mice (without any further adjuvant) exceeded up to 100%. This protection effect even lasted for at least three months after the immunization. Secreted IL-15:IL-15Rα clones challenging trigger anti-tumor response via CD4⁺ T, CD8⁺ T, and natural killer (NK) cell-dependent cytotoxicity. Our result suggested that cell-based vaccine secreting IL-15:IL-15Rα, may offer the new tools for immunotherapy to treat cancer.

• Biomolecules & Therapeutics
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• 제20권6호
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• pp.544-549
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• 2012

To examine the neuroprotective effects of ginsenoside R0, we investigated the effects of ginsenoside R0 in PC12 cells under an anoxic or oxidative environment with Edaravone as a control. PC12 neuroendocrine cells were used as a model target. Anoxic damage or oxidative damage in PC12 cells were induced by adding sodium dithionite or hydrogen peroxide respectively in cultured medium. Survival ratios of different groups were detected by an AlamarBlue assay. At the same time, the apoptosis of PC12 cells were determined with flow cytometry. The putative neuroprotective effects of ginsenoside R0 is thought to be exerted through enhancing the activity of antioxidant enzymes Superoxide dismutases (SOD). The activity of SOD and the level of malondialdehyde (MDA) and intracellular reactive oxygen species (ROS), were measured to evaluate the protective and therapeutic effects of ginsenoside R0. Ginsenoside R0 treated cells had a higher SOD activity, lower MDA level and lower ROS, and their survival ratio was higher with a lower apoptosis rate. It is suggested that ginsenoside R0 has a protective effect in the cultured PC12 cells, and the protection efficiency is higher than Edaravone. The protective mechanisms of these two are different. The prevent ability of ginsenoside R0 is higher than its repair ability in neuroprotection in vitro.

• 한국수정란이식학회지
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• 제31권1호
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• pp.39-46
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• 2016

Cryopreservation has been applied successfully in many mammalian species. Nevertheless, pig embryos, because of their greater susceptibility to cryoinjuries, have shown a reduced developmental competence. The aim of this study was to evaluate the survival status of vitrified-warmed porcine embryos. Forced blastocoele collapse (FBC) and non-FBC blastocysts are vitrified and concomitantly cultured in culture media which were supplemented with/without fetal bovine serum (FBS). Porcine vitrified-warmed embryos were examined in four different methods: group A, non-FBC without FBS; group B, non-FBC with FBS; group C, FBC without FBS; group D, FBC with FBS. After culture, differences in survival rates of blastocysts derived from vitrified-warmed porcine embryos were found in group A~D (39.5 (A) vs 52.5 (B) and 54.8 (C) vs 66.7% (D), respectively, p<0.05). Reactive oxygen species (ROS) level of survived blastocysts was lower in group D than that of another groups (p<0.05). Moreover, total cell number of survived blastocysts was higher in group D than that of other groups (p<0.05). Otherwise, group D showed significantly lower number of apoptotic cells than other groups ($2.0{\pm}1.5$ vs $3.2{\pm}2.1$, $2.8{\pm}1.9$, and $2.7{\pm}1.6$, respectively, p<0.05). Taken together, these results showed that FBS/FBC improves the developmental competence of vitrified porcine embryos by modulating intracellular levels of ROS and the apoptotic index during the vitrification/warming procedure. Therefore, we suggest that FBS and FBC are effective treatment techniques during the vitrification/warming procedures of porcine blastocysts.

• Animal cells and systems
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• 제11권1호
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• pp.39-50
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• 2007

Tau plays a role in numerous neuronal processes, such as vesicle transport, microtubule-plasma membrane interaction and intracellular localization of proteins. SUMO (Small Ubiquitin-like Modifier) modification (SUMOylation) appears to regulate diverse cellular processes including nuclear transport, signal transduction, apoptosis, autophagy, cell cycle control, ubiquitin-dependent degradation, as well as gene transcription. We noticed that putative SUMOylation site is localized at $^{340}K$ of $Tau(^{339}VKSE^{342})$ with the consensus sequence information (${\Phi}KxE$ ; where ${\Phi}$ represents L, I, V or F and x is any amino acid). In this report, we demonstrated that $^{340}K$ of Tau is the SUMOylation site and that a point mutant of Tau S214E (an analog of the phospho $^{214}S$ Tau) promotes its SUMOylation at $^{340}K$ and its nuclear or nuclear vicinity localization, by co-immunoprecipitation and confocal microscopy analysis. Further, we demonstrate that the Tau S214E (neither Tau S214A nor Tau K340R) mutant increases its protein stability. However, the SUMOylation at $^{340}K$ of Tau did not influence cell survival, as determined by FACS analysis. Therefore, our results suggested that the phosphorylation of Tau on $^{214}S$ residue promotes its SUMOylation on $^{340}K$ residue and nuclear vicinity localization, and increases its stability, without influencing cell survival.

• 대한약침학회지
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• 제22권3호
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• pp.154-159
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• 2019

Objectives: Toxoplasmosis is a worldwide health problem that caused by intracellular apicomplexan parasite, Toxoplasma gondii (T. gondii). Considering that the available drugs for toxoplasmosis have serious host toxicity, the aim of the current study was to survey the in vitro and in vivo anti-Toxoplasma activity of Zea mays (Z. mays) and Eryngium caucasicum (E. caucasicum) extracts. Methods: Four concentrations (5, 10, 25, and $50mg\;mL^{-1}$) of Z. mays and E. caucasicum methanolic extracts for 30, 60, 120, and 180 min were incubated with infected macrophages and then the viability of RH strain of T. gondii tachyzoites was evaluated by trypan blue staining method. Also, we evaluated the survival rate of acutely infected mice with the extracts (100 and $200mg\;kg^{-1}\;day^{-1}$) intraperitoneally for 5 days after infection with $2{\times}104$ tachyzoites of T. gondii. Results: The anti-Toxoplasma effect of the methanolic extracts were extremely significant compared to the negative control group in all exposure times (P < 0.05). The Z. mays (10, 25 and $50mg\;mL^{-1}$) killed 100% of the parasites after 180 and 120 min exposure, respectively. Also, high toxoplasmacidal activity was observed with E. caucasicum extract. Furthermore, treatment of experimentally infected mice with the Z. mays (100, $200mg\;kg^{-1}\;day^{-1}$) and E. caucasicum ($100mg\;kg^{-1}\;day^{-1}$) significantly increased their survival rate compared to untreated infected control (P < 0.05). Conclusion: These extracts are promising candidates for further medicine development on toxoplasmosis. However, further investigations are necessary to clarify effective fractions of the Z. mays and E. caucasicum extracts and the mechanisms of action.

• Journal of Medicine and Life Science
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• 제17권2호
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• pp.41-46
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• 2020

Metformin, a predominantly prescribed anti-diabetic drug for decades, has gained new insights for its anti-tumor activity in a variety of cancer cells. Our previous studies also showed the obvious pro-apoptotic activity of metformin and the underlying action mechanisms in hepatocellular carcinoma cells. Together with apoptosis, autophagy is a crucial intracellular process to determine the survival or death of cells under some stressful environments. The present study aimed to determine the role of autophagy in metformin-induced death of H4IIE hepatocellular carcinoma cells. Metformin blocked the formation of autophagosome and the expression of LC3A, generally described as a biomarker of autophagy. Inhibition of AMPK reversed the metformin-induced blockade of autophagy. Antioxidant (NAC) suppressed the metformin-induced cell death but not affected LC3A. The inhibition of protein kinase C totally restored the metformin-suppressed expression of LC3A. In summary, our present study suggests that autophagy is an anti-apoptotic player in metformin-induced apoptosis in H4IIE cells.

• BMB Reports
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• 제45권8호
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• pp.482-487
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• 2012

To identify the novel inhibitors of endoplasmic reticulum stress-induced cell death, we performed a high throughput assay with a chemical library containing a total of 3,280 bioactive small molecules. Cyclosporine A and bromocriptine were identified as potent inhibitors of thapsigargiin-induced cell death (cut-off at $4{\sigma}$ standard score). However, U74389G, the potent inhibitor of lipid peroxidation had lower activity in inhibiting cell death. The inhibition effect of cyclosporine A and bromocriptine was specific for only thapsigargin-induced cell death. The mechanism of inhibition by these compounds was identified as modification of the expression of glucose regulated protein-78 (GRP-78/Bip) and inhibition of phosphorylation of p38 mitogen activated protein kinase (MAPK). However, these compounds did not inhibit the same events triggered by tunicamycin, which was in agreement with the cell survival data. We suggest that the induction of protective unfolded protein response by these compounds confers resistance to cell death. In summary, we identified compounds that may provide insights on cell death mechanisms stimulated by ER stress.

• Applied Microscopy
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• 제43권3호
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• pp.117-121
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• 2013

Mitochondrion is an important intracellular organelle controlling energy production essential for cell survival. In addition, it is closely related to cellular apoptosis and necrosis. Linear, branched, circular, and ball-shaped mitochondria have been reported. Recent research suggests that mitochondrial morphology may reflect functional status of the cell. In this study, we investigated the density and ratio of the each morphological categories of mitochondria in a few normal cultured cells; astrocyte, HeLa and COS7 cells, of which metabolic activities are different, with high voltage electron microscopy. The absolute number and relative number per unit area of mitochondria was largest in astrocyte. But, the proportion of different mitochondrial shape was similar among cells. These results shows the numerical profiles but not morphological profiles of mitochondria are related to the metabolic activity of each cell line.