• Archives of Pharmacal Research
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• v.29 no.8
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• pp.699-706
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• 2006

The present study evaluated antioxidant and neuroprotective activities of hesperidin, a flavanone mainly isolated from citrus fruits, and its aglycone hesperetin using cell-free bioassay system and primary cultured rat cortical cells. Both hesperidin and hesperetin exhibited similar patterns of 1,1-diphenyl-2-picrylhydrazyl radical scavenging activities. While hesperidin was inactive, hesperetin was found to be a potent antioxidant, inhibiting lipid peroxidation initiated in rat brain homogenates by $Fe^{2+}$ and L-ascorbic acid. In consistence with these findings, hesperetin protected primary cultured cortical cells against the oxidative neuronal damage induced by $H_2O_2$ or xanthine and xanthine oxidase. In addition, it was shown to attenuate the excitotoxic neuronal damage induced by excess glutamate in the cortical cultures. When the excitotoxicity was induced by the glutamate receptor subtype-selective ligands, only the N-methyl-D-aspartic acid-induced toxicity was selectively and markedly inhibited by hesperetin. Furthermore, hesperetin protected cultured cells against the $A_{{\beta}(25-35)}-induced$ neuronal damage. Hesperidin, however, exerted minimal or no protective effects on the neuronal damage tested in this study. Taken together, these results demonstrate potent antioxidant and neuroprotective effects of hesperetin, implying its potential role in protecting neurons against various types of insults associated with many neurodegenerative diseases.

• Korean Journal of Pharmacognosy
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• v.36 no.3 s.142
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• pp.224-228
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• 2005

Protective effects of various natural flavonoids on carbon tetrachloride $(CCl_4)-induced$ hepatotoxicity were investigated in primary cultured rat hepatocytes. Some of these flavonoids decreased the ALT and LDH releases induced by $CCl_4$ in A dose-dependent manner. Neohesperidin, hesperetin, baicalin, baicalein and quercetin inhibited $CCl_4-induced$ alanine aminotransferase (ALT) release. In addition, quercetin, quercitrin, neohesperidin, baicalin, baicalein and naringin reduced $CCl_4$ induced lactate dehydrogenase (LDH) leakage. Among these flavonoids, quercitrin, quercetin, baicalin and baicalein possessed potent protective effects and were selected for the further investigation on lipid peroxidation. These four flavonoids inhibited dose dependently $CCl_4-induced$ lipid peroxidation. Especially, the protective effects of quercetin and baicalein were similar to silybin as a well-known hepatoprotective agent. These results suggest that these four flavonoids have significant cytoprotective effects and possibility of therapeutic effect on chemical-induced liver diseases.

• Korean Journal of Heritage: History & Science
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• v.36
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• pp.87-104
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• 2003

The Chungdo-type Pottery Culture, distributed through the middle part of the Korean peninsula, is chronologically located in the very former stage of the advent of ancient states. It has two different traditions of pottery manufacturing technique which are totally different in choosing raw materials, shaping, fixing and firing. It seems that two different traditions had been selectively applied by pottery type. In order to understand this peculiar cultural aspect, the pottery typology needs to be different from those applied to cultures where pottery was made and used under the single manufacturing tradition. This study tries to find the new pottery typology which best fits for the understanding the chronology of the Chungdo-Type Pottery Culture. For this purpose, I examined existing typologies, recognized their problems, and then build a new typology. As a result, I found that the former typologies misinterpreted the relative frequencies of each pottery type as different function or region. In this article, I propose the new pottery typology as building a primary classification within each function and region, and then synthesizing all of primary classifications. This new typology eliminates the factors of function and region in understanding the chronology of the Chungdo-Type Pottery Culture, and assorts the regional distinction by comparing pottery types in each region.

• Journal of English Language & Literature
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• v.56 no.1
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• pp.47-64
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• 2010

It is unfair that environmental pragmatism has been regarded as a mouthpiece for industrial expediency and business boosterism. John Dewey's radical pragmatism known as 'Instrumentalism' has provoked ecological fundamentalists' criticism more vehemently than any other pragmatic philosophies. However, most of the presumptive misunderstandings of such critics as Holmes Rolston, J. Baird Calliott, Erich Katz, C. A. Bowers and many others come from their limited or reduced reading of Deweyan pragmatism. The following three aspects of Deweyan pragmatism can work out in opening up a dialogical space with those eco-centrist thinkers mentioned above. First, the concept of Dewey's 'primary experience' can articulate the foundationalist view of nature, which is often found in aboriginal cultures. Second, as Andrew Light points out, ecological essentialism can share its metaphilosophical position with the pragmatist epistemology. While Anthony Weston pursues pluralism, admitting that the foundationalism might be one of the efficient approaches to nature, Eric Katz is also clearly attracted to the metaphilosophical element in Weston's argument that anyone who attempts to claim the 'inherent value' of non-human nature never possibly avoids a pitfall of anthropomorphism. Lastly, in a more comprehensive perspective, Dewey's pragmatism shows a philosophical complexity, what Larry A. Hickman calls 'post-postmodernism.' a dynamic interaction between modernism and postmodernism. Significantly enough, the environmental version of this complexity can procure a meeting ground between foundationalist ecology and the pragmatic view of nature.

• Animal Bioscience
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• v.35 no.11
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• pp.1787-1799
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• 2022

Objective: Choline deficiency, one main trigger for nonalcoholic fatty liver disease (NAFLD), is closely related to lipid metabolism disorder. Previous study in a choline-deficient model has largely focused on gene expression rather than gene structure, especially sparse are studies regarding to alternative splicing (AS). In modern life science research, primary hepatocytes culture technology facilitates such studies, which can accurately imitate liver activity in vitro and show unique superiority. Whereas limitations to traditional hepatocytes culture technology exist in terms of efficiency and operability. This study pursued an optimization culture method for duck primary hepatocytes to explore AS in choline-deficient model. Methods: We performed an optimization culture method for duck primary hepatocytes with multi-step digestion procedure from Pekin duck embryos. Subsequently a NAFLD model was constructed with choline-free medium. RNA-seq and further analysis by rMATS were performed to identify AS events alterations in choline-deficency duck primary hepatocytes. Results: The results showed E13 (embryonic day 13) to E15 is suitable to obtain hepatocytes, and the viability reached over 95% by trypan blue exclusion assay. Primary hepatocyte retained their biological function as well identified by Periodic Acid-Schiff staining method and Glucose-6-phosphate dehydrogenase activity assay, respectively. Meanwhile, genes of alb and afp and specific protein of albumin were detected to verify cultured hepatocytes. Immunofluorescence was used to evaluate purity of hepatocytes, presenting up to 90%. On this base, choline-deficient model was constructed and displayed significantly increase of intracellular triglyceride and cholesterol as reported previously. Intriguingly, our data suggested that AS events in choline-deficient model were implicated in pivotal biological processes as an aberrant transcriptional regulator, of which 16 genes were involved in lipid metabolism and highly enriched in glycerophospholipid metabolism. Conclusion: An effective and rapid protocol for obtaining duck primary hepatocytes was established, by which our findings manifested choline deficiency could induce the accumulation of lipid and result in aberrant AS events in hepatocytes, providing a novel insight into various AS in the metabolism role of choline.

• Korean Journal of Environmental Agriculture
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• v.24 no.2
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• pp.146-152
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• 2005

The objective of present study was to investigate the effect of onion extracts on mercuryinduced cytotoxicity, lipid peroxidation and antioxidant enzyme activities in primary monolayer cultures of rat hepatocytes. Primary cultures of rat hepatocytes were incubated for 6 hr in the presence of various concentrations (0, 1, 5, 10, 30 or 50 ppm) of $HgCl_2$. Cytotoxicity and cell viability were determined by measuring glutamic oxaloacetic transaminase (GOT) activity, lactate dehydrogenase (LDH) activity and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) value. Lipid peroxidation w as evaluated using thiobarbituric acid reactive substances (TBARS) assay. Effects of onion extract on antioxidant system were determined by measuring catalase, glutathione peroxidase (GSH-Px), glutathione reductase (GSH-Rd) activities as well as DPPH free radical scavenging activity. $HgCl_2$ at the concentration of 10 ppm increased GOT activity and TBARS concentration but decreased %MTT reduction, whereas $HgCl_2$ at the concentration of 30 ppm increased LDH activity, representing that $HgCl_2$ caused cytotoxicity and lipid peroxidation in dose-dependent manner, $HgCl_2$ at the concentration of 30 ppm significantly decreased catalase, GSH-Px and GSH-Rd activities. When primary cultures of rat hepatocytes were incubated with various concentrations (0, 0.01, 0.05, 0.1 or 0.3 mg/ml) of onion extract for 6 hr in the presence of 30 ppm of $HgCl_2$, onion extracts at the concentration of 0.05 mg/ml decreased GOT activity, but increased %MTT reduction by 30 ppm of $HgCl_2$. $HgCl_2-induced$ LDH activity and TBARS concentration were decreased by onion extract at the concentration of 0.01 mg/ml. Taken together, onion extract prevented H$HgCl_2-induced$ hepatocyte injury and lipid peroxidation. Onion extracts at the concentration of 0.1 mg/ml almost or completely inhibited $HgCl_2-induced$ catalase and GSB-Px activities. GSH-Rd activity, however, was not affected by onion extract. Free radical scavengjing activity was increased as concentration of onion extract increased. Onion extract at the concentrion of 5 mg/ml possesed mote than 93% scavenging activity comparing to 100% radical scavenging activity by pyrogallol solution as a reference. These results demonstrate that onion extracts suppressed mercury-induced cytoctoxicity and lipid peroxidation by scavenging free radical and increasing catalase and GSH-Px activities.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.1
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• pp.9-14
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• 1999

Factors affecting gene gun-mediated expression of the human erythropoietin gene were investigated in primary cultured oviduct cells from laying hens. The human erythropoietin gene was transfected by a gene gun method at $1.25{\mu}g$ per dish, and cultured in a synthetic serum-free medium for 72 hrs. The concentration of human erythropoietin mRNA was determined by RNA : RNA solution hybridization. In experiment 1, the effect of changing the shooting pressure of DNA-coated microparticles with nitrogen gas was tested at 20 and $60kgf/cm^2$. The results showed that the erythropoietin mRNA concentration was significantly higher at 60 than $20kgf/cm^2$. In experiment 2, the effects of supplementing the medium with fetal calf serum at 10%, and raising the shooting pressure from 60 to $80kgf/cm^2$ on the cell number and erythropoietin gene expression were examined. Although supplementation with fetal calf serum significantly increased the cell numbes compared with no supplemented controls (p < 0.05), erythropoietin mRNA concentration per $10^3$ cells was not affected. Raising the shooting pressure from 60 to $80kgf/cm^2$ did not affect either of the parameters, In experiment 3, the effect of supplementing ascorbate 2-phosphate at 0.5 mM was tested. The results indicated that the ascorbate supplementation significantly increased the cell number (p < 0.05), and tended to increase erythropoietin mRNA concentration (p < 0.1). Thus, for human erythropoietin gene expression by using the gene gun method, shooting pressure with nitrogen gas should be sufficient at $60kgf/cm^2$ and supplementation with ascorbate phosphate would be useful to enhance not only the cell proliferation but also erythropoietin gene expression.

• Journal of Environmental Science International
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• v.13 no.4
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• pp.413-420
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• 2004

The objectives of present study were to investigate the effects of benzo[a]pyrene(BaP) on cytotoxicity, lipid peroxidation and antioxidant enzymes in rat hepatocyte primary culture. Primary cultures of rat hepatocytes were incubated for 24 hr, 48 hr or 72 hr in the presence of various concentrations (0, 10, 20, 30, 50 or 100 $\mu.$ M) of BaP. Cytotoxicity and cell viability were determined by measuring glutamic oxaloacetic transaminase(GOT) activity, lactate dehydrogenase(LDH) activity and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide(MIT) value. Lipid peroxidation was evaluated using thiobarbituric acid reactive substances(TBARS) assay. Effects on antioxidant system were determined by measuring glutathione peroxidase(GPx) activity, glutathione reductase(GR) activity and glutathione concentration. Activities of GOT and LDH, MTT value as well as TBARS concentration were not affected by up to 100 $\muM$ of BaP for 24 hr incubation. However, BaP at the concentration of 50 $\muM$ for 48 hr incubation or at the concentration of 30 $\muM$ for 72 hr incubation began to increase LDH activity and TBARS concentration but decrease MTT value, representing that BaP caused cytotoxicity and decreased cell viability in dose- and time-dependent manners. GPx activity began to be decreased by BaP at the concentration of 50 $\muM$ for 72 hr incubation. Whereas, GR activity began to be decreased by BaP at the concentration of 20 $\muM$ for 72 hr incubation. Glutathione concentration began to be decreased by BaP at the concentration of 20 $\muM$ for 72 hr incubation and was further reduced to 90% by 100 $\muM$ of BaP. These results demonstrate that BaP caused cytoctoxicity and decreased cell viability by increasing lipid peroxidation and decreasing glutathione concentration as well as activities of GPx and GR.

• Journal of Life Science
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• v.22 no.5
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• pp.621-626
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• 2012

$Drosophila$ $melanogaster$ has been used as a useful model to study development and disease. In this study, we established the primary culture method of $Drosophila$ in the intestine to understand how intestinal stem cells (ISCs) mediate tissue repair during infection and disease. To obtain intestinal cells, we separated intestines from adult flies and isolated single cells by enzymatic treatment. The survival of cultured cells was measured using MTS-analysis. The maximum growth rate of the cells was observed on the 9th day after seeding. In addition, the presence of ISCs and enteroendocrine cells was confirmed by delta and prospero staining. Accordingly, we supposed that $Drosophila$ $melanogaster$ gut cells established in this study are probably useful in studies about intestinal stem cell regulation and various diseases occurring in the intestine.

• YAKHAK HOEJI
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• v.51 no.2
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• pp.115-125
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• 2007

The aim of this study was to investigate the protective activities of daidzin, daidzein, genistein or puerarin, active isoflavonoids of Puerariae Radix, on the hepatocyte injury induced by carbon tetrachloride (CCl$_4$, 10 mM), tert-butyl hydroperoxide (TBH, 0.5 mM) and D-galactosamine (GalN, 30 mM). Primary cultures of rat hepatocytes (18 hr cultured) were treated with CCl$_4$, TBH or GalN and various concentrations (0.1, 1, 10 and 100 ${\mu}$M) of daidzin, daidzein, genistein or puerarin. CCl$_4$ significantly increased the levels of lactate dehydrogenase (LDH), alanine aminotransferase (ALT) and aspartate aminotransferase (AST). The increase in LDH level was attenuated by daidzein, genistein and puerarin. Puerarin also inhibited the increase in AST level induced by CCl$_4$. The increases in LDH and ALT levels induced by TBH were significantly attenuated by daidzin and genistein treatments. GalN markedly increased the levels of LDH, ALT and AST These increases were significantly attenuated by daidzein. Daidzin also inhibited the increases in LDH and AST levels induced by GalN. The increases in LDH and ALT levels were attenuated by genistein and puerarin, respectively. These results suggest that daidzin and daidzein possess hepatoprotective activities.