• The Korean Journal of Malacology
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• v.30 no.3
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• pp.189-196
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• 2014

A significant production decrease has been witnessed for the Pacific oysters, Crassostrea gigas farmed in the western coastal waters of Korea, presumably by the loss of physiological viability. We evaluated the viability in terms of health indicators, the condition indices and hemocyte apoptosis rates of the oysters inhabiting two representative farming sites, Incheon and Taean each with different environmental variables. In our monthly measurements for the whole year 2013, the indicators were location specific. The condition indices of Incheon were highly variable, 1.67-8.58%, while those of Taean were less, 2.28-5.57%. The condition indices decreased during the spawning seasons, July and September in common. The two oysters exhibited also differed in the apoptotic activities of hemocyte, highly active, 4.03-30.15% for Incheon oysters and less active, 2.87-17.48% for Taean oysters. One thing we could identify was the two measurements were adverse during the critical seasons of spawning, reminiscent of being a useful tool for a health indicator for the oysters. Similar trend was also observed in the time when change in temperature was extreme. The findings in this study are highly indicative of health indicators for the oyster aquaculture.

• Journal of Microbiology and Biotechnology
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• v.27 no.6
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• pp.1163-1170
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• 2017

Clostridium difficile releases two exotoxins, toxin A and toxin B, which disrupt the epithelial cell barrier in the gut to increase mucosal permeability and trigger inflammation with severe diarrhea. Many studies have suggested that enteric nerves are also directly involved in the progression of this toxin-mediated inflammation and diarrhea. C. difficile toxin A is known to enhance neurotransmitter secretion, increase gut motility, and suppress sympathetic neurotransmission in the guinea pig colitis model. Although previous studies have examined the pathophysiological role of enteric nerves in gut inflammation, the direct effect of toxins on neuronal cells and the molecular mechanisms underlying toxin-induced neuronal stress remained to be unveiled. Here, we examined the toxicity of C. difficile toxin A against neuronal cells (SH-SY5Y). We found that toxin A treatment time- and dose-dependently decreased cell viability and triggered apoptosis accompanied by caspase-3 activation in this cell line. These effects were found to depend on the up-regulation of reactive oxygen species (ROS) and the subsequent activation of p38 MAPK and induction of $p21^{Cip1/Waf1}$. Moreover, the N-acetyl-$\text\tiny L$-cysteine (NAC)-induced down-regulation of ROS could recover the viability loss and apoptosis of toxin A-treated neuronal cells. These results collectively suggest that C. difficile toxin A is toxic for neuronal cells, and that this is associated with rapid ROS generation and subsequent p38 MAPK activation and $p21^{Cip1/Waf1}$ up-regulation. Moreover, our data suggest that NAC could inhibit the toxicity of C. difficile toxin A toward enteric neurons.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.7
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• pp.2939-2946
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• 2015

Many of the anti-cancer agents currently used have an origin in natural sources including plants. Aloe vera is one such plant being studied extensively for its diverse health benefits, including cancer prevention. In this study, the cytotoxic potential of Aloe vera crude extract (ACE) alone or in combination with cisplatin in human breast (MCF-7) and cervical (HeLa) cancer cells was studied by cell viability assay, nuclear morphological examination and cell cycle analysis. Effects were correlated with modulation of expression of genes involved in cell cycle regulation, apoptosis and drug metabolism by RT-PCR. Exposure of cells to ACE resulted in considerable loss of cell viability in a dose- and time-dependent fashion, which was found to be mediated by through the apoptotic pathway as evidenced by changes in the nuclear morphology and the distribution of cells in the different phases of the cell cycle. Interestingly, ACE did not have any significant cytotoxicity towards normal cells, thus placing it in the category of safe chemopreventive agent. Further, the effects were correlated with the downregulation of cyclin D1, CYP 1A1, CYP 1A2 and increased expression of bax and p21 in MCF-7 and HeLa cells. In addition, low dose combination of ACE and cisplatin showed a combination index less than 1, indicating synergistic growth inhibition compared to the agents applied individually. In conclusion, these results signify that Aloe vera may be an effective anti-neoplastic agent to inhibit cancer cell growth and increase the therapeutic efficacy of conventional drugs like cispolatin. Thus promoting the development of plant-derived therapeutic agents appears warranted for novel cancer treatment strategies.

• Preventive Nutrition and Food Science
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• v.16 no.1
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• pp.18-23
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• 2011

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by neuronal loss and extracellular senile plaques containing $\beta$-amyloid peptide (A$\beta$). The deposition of the A$\beta$ peptide following proteolytic processing of amyloid precursor protein (APP) by $\beta$-secretase (BACE1) and $\gamma$-secretase is a critical feature in the progression of AD. Among the plant extracts tested, the ethanol extract of Petasites japonicus leaves showed novel protective effect on B103 neuroblastoma cells against neurotoxicity induced by A$\beta$, as well as a strong suppressive effect on BACE1 activity. Ethanol extracts of P. japonicus leaves were sequentially extracted with methylene chloride, ethyl acetate and butanol and evaluated for potential to inhibit BACE1, as well as to suppress A$\beta$-induced neurotoxicity. Exposure to A$\beta$ significantly reduced cell viability and increased apoptotic cell death. However, pretreatment with ethyl acetate fraction of P. japonicus leaves prior to A$\beta$ (50 ${\mu}M$) significantly increased cell viability (p<0.01). In parallel, cell apoptosis triggered by A$\beta$ was also dramatically inhibited by ethyl acetate fraction of P. japonicus leaves. Moreover, the ethyl acetate fraction suppressed caspase-3 activity to the basal level at 30 ppm. Taken together, these results demonstrated that P. japonicus leaves appear to be a useful source for the inhibition and/or prevention of AD by suppression of BACE1 activity and attenuation of A$\beta$ induced neurocytotoxicity.

• Molecules and Cells
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• v.37 no.7
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• pp.540-546
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• 2014

Several types of genetic and epigenetic regulation have been implicated in the development of drug resistance, one significant challenge for cancer therapy. Although changes in the expression of non-coding RNA are also responsible for drug resistance, the specific identities and roles of them remain to be elucidated. Long non-coding RNAs (lncRNAs) are a type of ncRNA (> 200 nt) that influence the regulation of gene expression in various ways. In this study, we aimed to identify differentially expressed lncRNAs in 5-fluorouracil-resistant colon cancer cells. Using two pairs of 5-FU-resistant cells derived from the human colon cancer cell lines SNU-C4 and SNU-C5, we analyzed the expression of 90 lncRNAs by qPCR-based profiling and found that 19 and 23 lncRNAs were differentially expressed in SNU-C4R and SNU-C5R cells, respectively. We confirmed that snaR and BACE1AS were down-regulated in resistant cells. To further investigate the effects of snaR on cell growth, cell viability and cell cycle were analyzed after transfection of siRNAs targeting snaR. Down-regulation of snaR decreased cell death after 5-FU treatment, which indicates that snaR loss decreases in vitro sensitivity to 5-FU. Our results provide an important insight into the involvement of lncRNAs in 5-FU resistance in colon cancer cells.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.5
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• pp.668-674
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• 2014

The objective of the present study was to investigate the protective and free radical scavenging effects of conventionally and organically cultivated kale juices against oxidative damage in $LLC-PK_1$ cells. The DPPH, NO, $O_2{^-}$, and ${\cdot}OH$ radical scavenging activities of organically cultivated kale were higher than those of conventionally cultivated kale juice. Oxidative damage induced by AAPH (2,2'-azobis(2-amidinopropane) dihydrochloride), SNP (sodium nitroprusside), pyrogallol, and SIN-1 (3-morpholinosydnonimine) led to loss of cell viability and increased lipid peroxidation in LLC-PK1 cells, whereas treatment with vegetable juices, especially organically cultivated kale juices, significantly increased cell viability and inhibited lipid peroxidation in a dose-dependent manner (P<0.05). These results suggest that organically cultivated kale juices have protective roles against oxidative stress induced by free radicals.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.11
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• pp.1501-1508
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• 2004

In this study the effect of extenders and temperatures on sperm viability and fertilizing capacity of boar sperm during long-term storage was investigated. Acrosomal integrity, membrane integrity, motility and hypo-osmotic resistance were evaluated by fluorescence and light microscopy. An in vitro fertilization test was performed to assess the fertilizing capacity of stored spermatozoa. The five diluents tested were ranked according to their ability to maintain sperm functional parameters and Zorlesco (ZO) extender with BSA or with PVA instead of BSA produced the best results. Zorlesco extender substituted with PVA (ZO+PVA) was found to maintain motility both at 15 and 20$^{\circ}C$. within 5 days of storage, but the quality of semen stored at 15$^{\circ}C$ decreased thereafter as compared to semen stored at 20$^{\circ}C$ Semen stored at 5$^{\circ}C$ demonstrated rapid loss of motility already within 24 h. Both fertilization and cleavage of semen stored at 20$^{\circ}C$ in ZO substituted with PVA instead of BSA did not change significantly until day 8 of storage. It is therefore concluded that PVA can be used to substitute for BSA and 20$^{\circ}C$ was more suitable than 15$^{\circ}C$ for boar semen storage, and in vitro fertilizing capacity of spermatozoa was maintained for at least 8 days in ZO+PVA at 20$^{\circ}C$.

• The Journal of Internal Korean Medicine
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• v.28 no.3
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• pp.544-559
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• 2007

Objectives : This study was designed to evaluate the anti-diabetes and vasoelasticity effects of Mori Folium and Aurantii Fructus in streptozotocin-induced type II diabetes mellitus model. Methods : The anti-diabetic effect of Mori Folium and Aurantii Fructus on rats induced with diabetes by streptozotocin was investigated through analyses of changes in body weight, blood glucose, urine volume of rats, viability of human umbilical vein endothelial cells(HUVECs), and elasticity of descending thoracic aorta in rats. The subjects in this study were divided into four groups(n=15): a normal group without any treatment (Con), a normal group with Mori Folium and Aurantii Fructus treatment(Con+P), a diabetes group induced by streptozotocin(STZ), and a Mori Folium and Aurantii Fructus treatment group under diabetes induced by streptozotocin(STZ+P). Rats were administered streptozotocin to induce diabetes. Results : The study showed that Mori Folium and Aurantii Fructus significantly reduced highly increased blood glucose levels(p<0.01) and prevented the diabetic rats from weight loss(p<0.01) and polyurea(p<0.05), Mori Folium and Aurantii Fructus also recovered decreased viability of HUVECs(p<0.01) and damaged elasticity of aorta induced by the streptozotocin (p<0.01). Conclusions: It was concluded from the results that Mori Folium and Aurantii Fructus have a distinct anti-diabetes effect and they also prevent damage of blood vessel induced by diabetes. resulting in prevention of cardiovascular diseases ascribed to diabetes.

• Journal of Wetlands Research
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• v.18 no.3
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• pp.282-285
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• 2016

Peregrine falcon (Falco peregrinus) are listed as endangered species and Natural monument #323 in Korea, and this study examined the possibility of extinct of peregrine falcon in Jang Hang wetland near Han river using with the application of Population Viability Analysis (PVA) technique. In Jang Hang wetland areas population was monitored during 1999-2005 averaging 10.8 individuals and PVA analysis was done for the 5 years (2015-2020) using the average population size. Using the initial population was estimated 20% of extinct rate during the time. This estimation was quite low considering water pollution and loss of habitat. Also PVA only used population size lacking in other life history information. Nonetheless falcon population can be in risk of extinction if the current construction of crossovers in the river, cement bank are maintained. Long term information regarding life history needs essential.

• Preventive Nutrition and Food Science
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• v.13 no.2
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• pp.90-94
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• 2008

The protective effect of chungkukjang from Sunchang province against oxidative stress was evaluated in the cellular system using LLC-$PK_1$ renal epithelial cells. The LLC-$PK_1$ cells showed decrease in cell viability and elevation in lipid peroxidation by the treatment with the generators of nitric oxide (NO) and superoxide anion ($O_2^-$) produced by sodium nitrouprusside and pyrogallol, respectively. However, the methanol extract of chungkukjang significantly inhibited cellular loss and lipid peroxidation in a dose-dependent manner; in particular K chungkukjang (KC) exerted the strongest protective effect. In addition, the protective effect of chungkukjang from 3-morpholinosydnonimine, as a source of peroxynitrite, with simultaneous generations of NO and $O_2^-$, was also studied. Treatment with chungkukjangs significantly preserved the cell viability and inhibited lipid peroxidation caused by SIN-1 with dose-dependence. The present study suggests that chungkukjang from Sunchang province, especially KC, would have protective potential from oxidative stress induced by free radicals under cellular oxidative damage.