• Journal of Photoscience
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• v.9 no.2
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• pp.229-232
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• 2002

There are two distinct UV-responsive signaling pathways in UV-irradiated mammalian cells, i.e., the DNA damage-dependent and -independent pathways. The former occurs in nucleus and results in growth arrest and apoptosis via post-translational modification of p53. The latter is initiated by oxidative stress and/or by damages in cell membrane or cytoplasm, which activate signaling cascade through intracellular molecules including mitogen activated protein kinases (MAPK). In normal human fibroblastic cells, all of MAPK family members, extracellular signal-related kinases (ERK), c-Jun N-terminal kinases (JNK) and p38, were rapidly phosphorylated following UV-irradiation. ERK phosphorylation was suppressed by an inhibitor of receptor tyrosine kinases (RTK). As ERK usually responds to mitogenic stimuli from RTK ligands, UV-induced ERK phosphorylation may be linked to the proliferation of survived cells. In contrast, phosphorylation of JNK and p38, as well as apoptosis, were modulated by the level of UV-generated oxidative stress Therefore, JNK and p38 may take part in oxidative stress-mediated apoptosis. Phosphorylation of p53 at Ser and Thr residues are essential for stabilization and activation of p53. Among several sites reported, we confirmed phosphorylation at Ser-15 and Ser-392 after UV-irradiation. Both of these were inhibited by a phosphoinositide 3-kinase inhibitor, presumably due to the shutdown of signals from DNA damage to p53. Phosphorylation at Ser-392 was also sensitive to an antioxidant and a p38 inhibitor, suggesting that Ser-392 of p53 is one of the possible points where DNA damage-dependent and -independent apoptic signals merge. Thus, MAPK pathway links UV-induced intracellular signals to the nuclear responses and modifies DNA damage-dependent cellular outcome, resulting in the determination of cell death.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.6
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• pp.547-551
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• 2013

We recently reported a Philyra pisum lectin (PPL) that exerts mitogenic effects on human lymphocytes, and its molecular characterization. The present study provides a more detailed characterization of PPL based on the results from a monosaccharide analysis indicating that PPL is a glycoprotein, and circular dichroism spectra revealing its estimated ${\alpha}$-helix, ${\beta}$-sheet, ${\beta}$-turn, and random coil contents to be 14.0%, 39.6%, 15.8%, and 30.6%, respectively. These contents are quite similar to those of deglycosylated PPL, indicating that glycans do not affect its intact structure. The binding properties to different pathogen-associated molecular patterns were investigated with hemagglutination inhibition assays using lipoteichoic acid from Gram-positive bacteria, lipopolysaccharide from Gram-negative bacteria, and both mannan and ${\beta}$-1,3-glucan from fungi. PPL binds to lipoteichoic acids and mannan, but not to lipopolysaccharides or ${\beta}$-1,3-glucan. PPL exerted no significant antiproliferative effects against human breast or bladder cancer cells. These results indicate that PPL is a glycoprotein with a lipoteichoic acid or mannan-binding specificity and which contains low and high proportions of ${\alpha}$-helix and ${\beta}$-structures, respectively. These properties are inherent to the innate immune system of P. pisum and indicate that PPL could be involved in signal transmission into Gram-positive bacteria or fungi.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.114-114
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• 2003

Epidermal growth factor (EGF) induces well-documented mitogenic and differentiating effects on murine and bovine preimplantation embryos. However, the effects of EGF on apoptosis and implantation-related gene expression in bovine embryos developing in vitro have not been evaluated. The objective of this study was to determine the effects of exogenous EGF in the presence and absence of BSA on the preimplantation development of bovine embryos. In addition, we measured cell number, apoptosis, and expression of apoptosis and implantation-related genes of the blastocysts that developed in these culture conditions. In vitro produced bovine embryos were randomly cultured in the same medium containing 0 or 10 ng/ml EGF in the presence and absence of 0.8% BSA. More 2-cell embryos developed into blastocysts at day 7 when BSA was present than when BSA was absent. The addition of 10 ng/$m\ell$ EGF into the medium did not significantly increase the developmental rate and the cell numbers per blastocyst. However, addition of EGF in the presence of 0.8% BSA significantly reduced the degree of apoptosis in the blastocysts (P<0.01). To investigate whether EGF modulates mRNA expression of apoptosis-related genes, mRNA was prepared from single blastocysts and each preparation was subjected to RT-PCR for Bcl-2 and Bax transcripts. EGF did not alter the relative abundance of Bax gene expression in the presence of BSA, but increase Bcl-2 (P<0.01) The relative abundance of Interferon tau expression was increased by EGF treatment in the presence of BSA. These results suggest that EGF and BSA synergistically enhance Bcl-2 and interferone tau gene expression, which may result in a net increase in viability in bovine embryos.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.1
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• pp.106-115
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• 2010

Phosphorylated dextran (P-Dex) is an acidic polysaccharide that functions as an immune adjuvant. P-Dex is known to regulate immune response by maintaining a balance between Th1 and Th2 cells in vitro, and thus may also be important in the control of allergic reactions. In the current study, we report the optimum conditions required for the efficient phosphorylation of dextran without toxicity. We found that when dextran was heated at 160${^{\circ}C}$ for 24 h in phosphate buffer (pH 5.0), the resulting P-Dex demonstrated the highest phosphorus content (6.8%). We also report that P-Dex enhances mitogenic activity in mouse splenocytes and induces expression of CD69 and CD86 on the surface of B cells and dendritic cells (DC) in vitro. Oral administration of P-Dex to ovalubmin (OVA)-immunized mice was found to reduce antigen-induced cell proliferation and suppress the expression of CD86 on Th2-inducing DC via exogenous OVA stimulation. P-Dex was also found to increase IL-10 expression in the splenocytes of treated mice. These findings suggest that oral administration of P-Dex increases immunological tolerance and improves the specificity of immunological response to specific antigens.

• The Journal of Internal Korean Medicine
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• v.30 no.3
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• pp.451-464
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• 2009

Background and Objective : Cyperus rotundus L. (CR) is a commonly used herbal medicine in Asian countries such as Korea, China and Japan. The present study was designated to evaluate the direct effects of CR on helper T cell activities and on Th1/Th2 lineage development in vitro. Materials and Methods : Spleen cells from 8 week BALB/c mice were cultured in CR extracts containing medium without activation for 24 hours and with activation for 48 hours. CD4+ T cells were isolated and analyzed for mRNA expression levels of INF-$\gamma$, IL-4, T-bet and GATA-3 by RT-PCR and secretion cytokines levels of INF-$\gamma$, IL-4, IL-5 and IL-10 by ELISA. Results : The results demonstrated that CR had no mitogenic effects on unstimulated CD4+ T cells, but augmented CD4+ T-cell proliferation upon activation with anti-CD3/anti-CD28 antibodies in a dose-dependent manner. CR treatment significantly increased CD4+ T cell population and the IFN-$\gamma$ expression was significantly enhanced, while IL-4 expression was significantly decreased. In addition, in vitro Th1/Th2 polarization experiments revealed that CR enhanced IFN-$\gamma$ secretion in Th1 cells, but reduced the IL-4 in Th2 cells in a dose-dependent manner. Conclusion : These results suggest that CR treatment could be a desirable alternative therapy for the prevention or correction of Th2 dominant pathological disorders, such as allergy and asthma.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.5
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• pp.1347-1355
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• 2004

In this study, the immunological effect of a traditional Korea herbal acupuncture, that has been widely used for the treatment of various immunological disorders including inflammation in Korea, was examined in vitro and in vivo. In our previous study demonstrated that BV increased the expression of IFN-γ mRNA, that plays pivotal role in T cell response. This study was designated to evaluate the effect of BV on helper T cell development by monitoring Th1/Th2 specific cytokine secretion patterns in artificially induced Th1/Th2 polarized condition and in vivo. The results demonstrated that BV didn't have mitogenic effects on the unstimulated CD4+ T cell, but increased the CD4+ T cell proliferation upon activation with anti-CD3/CD28 antibody. The Th1 cells were over-populated dramatically in Th1 driven condition with BV treatment, while the Th2 cells were increased slightly in Th2 skewed condition. Furthermore, under Th1-skewed conditions, the level of IFN-γ was considerably increased with BV treatment. Besides, the expression of T-bet, a transcription factor that plays pivotal role in Th1 lineage programming, was increased with BV treatment. The expressions of IFN-γ and T-bet were also significantly increased in vivo. The results that Th1 specific cytokine secretion were considerably increased and Th2 specific cytokine secretion were not significantly changed in vitro and in vivo indicated that BV enhances Th1 lineage development, Therefore, these results suggest that BV might be desirable agent for correction of Th1 dominant pathological disorders.

• Journal of Nutrition and Health
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• v.20 no.5
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• pp.350-366
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• 1987

This research was designed to study the effect of Korean dietary lipids on the lipid metabolism and the immune function in young rats . The three different lipid sources were compared lard, perilla oil and fish oil. Three different levels of lipid in the diet, 2%, 15% and 30%,on the weight basis, were included. After four weeks feeding, the rats were sacrified and blood sample was collected to analyze for the total lipid, TG and cholesterol contents in serum. The HDL fraction in serum was seperated by the electrophoresis of lipoproteins. The immune responses were measured by the blastogenesis of spleen lymphocyte stimulated by PHA and in serum were measured. The following results were obtained. Lower body weight gain was shown in 30% lipid diet fed group on the isocaloric basis. In concerning the different dietary lipid sources, there were significantly lower boyd weight gain in fish oil than in perilla seed oil and lard group in 30% lipid groups. Deposition of body fat expressed by epididymal fat pad in serum were significantly different among perilla seed oil, lard and fish oil groups. Perilla seed oil group showed lowest level of total lipid and TG in serum regardless of dietary fat level. The feeding perilla seed oil to rats was resulted in lower serum cholesterol levels than lard in all three levels of fats tested. The HDL fraction was elevated in perilla seed oil group at the high fat level. The stimulating responses of lymphycotes by PHA did not seem to be influenced by different dietary fat sources. However, conA mitogenic responses was significantly increased in perilla seed oil group. The lower level of perilla seed oil (2%, 15%) showed slightly higher responses of ConA, indicating that lower level of perilla seed oil might have stimulatory response on the immune response. The number of antibody forming cells of spleen against SRBC was increased in 30% fat level for all the three kind of fats. However, no effect has been found in plaque forming cell response by the differences in dietary fat sources. There were no significant differences in serum IgG and IgA levels in all dietary groups.

• Korean Journal of Poultry Science
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• v.39 no.1
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• pp.17-25
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• 2012

Coccidiosis control programs such as vaccines or in-feed anticoccidials are commonly practiced in the poultry industry to improve growth performance and health of commercial broiler chickens. In this study, we assessed the effects of various coccidiosis control programs (e.g., in ovo vaccination, synthetic chemicals, and antibiotic ionophores) on immune status of broiler chickens vaccinated against infectious bronchitis virus and Newcastle disease virus (ND) and raised on an Eimeria-contaminated used litter. In general, the levels of ${\alpha}$-1-acid glycoprotein, an acute phase protein, were altered by the treatments when measured at 34 days of age. Splenocyte subpopulations and serum antibody titers against ND were altered by various coccidiosis control programs. In-ovo-vaccinated chickens exhibited highest mitogenic response when their spleen cells were stimulated with concanavalin A (Con A) at 7 days of age. It is clear from this study that the type of coccidiosis control program influenced various aspects of innate and adaptive immune parameters of broiler chickens. Further studies will be necessary to delineate the underlying relationship between the type of coccidiosis control program and host immune system and to understand the role of other external environmental factors such as gut microbiota on host-pathogen interaction in various disease control programs.

• Biomolecules & Therapeutics
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• v.19 no.3
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• pp.288-295
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• 2011

Amyloid beta ($A{\beta}$)-induced neurotoxicity is a major pathological mechanism of Alzheimer's disease (AD). In this study, we investigated the inhibitory effect of L-theanine, a component of green tea (Camellia sinensis) on $A{\beta}_{1-42}$-induced neurotoxicity and oxidative damages of macromolecules. L-theanine inhibited $A{\beta}_{1-42}$-induced generation of reactive oxygen species, and activation of extracellular signal-regulated kinase and p38 mitogenic activated protein kinase as well as the activity of nuclear factor kappa-B. L-theanine also signifi cantly reduced oxidative protein and lipid damage, and elevated glutathione level. Consistent with the reduced neurotoxic signals, L-theanine (10-50 ${\mu}g$/ml) concomitantly attenuated $A{\beta}_{1-42}$ (5 ${\mu}M$)-induced neurotoxicity in SK-N-MC and SK-N-SH human neuroblastoma cells. These data indicate that L-theanine on $A{\beta}$-induced neurotoxicity prevented oxidative damages of neuronal cells, and may be useful in the prevention and treatment of neurodegenerative disease like AD.

• The Journal of Internal Korean Medicine
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• v.28 no.4
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• pp.681-693
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• 2007

Background and Objective : Atractylodes japonica (AJ) is a commonly-used herbal medicine in Asian countries such as Korea, China and Japan. The present study was designated to evaluate the direct effects of AJ on helper T cell activities and on Th1/Th2 lineage development in vitro. Materials and Methods : Spleen cells from 8-week BALB/c mice were cultured in CR extracts containing medium without activation for 24 hours and with activation for 48 hours. CD4+ T cells were isolated and analyzed for mRNA expression levels of INF-$\gamma$, IL-4, T-bet and GATA-3 by RT-PCR and secretion cytokines levels of INF-$\gamma$, IL-2, IL-4, IL-5 and IL-10 by ELISA. Results : The results demonstrated that AJ had no mitogenic effects on unstimulated CD4+ T cells, but augmented CD4+T-cell proliferation upon activation with anti-CD3/anti-CD28 antibodies in a dose-dependent manner. AJ treatment significantly increased CD4+ T cell population and IFN-$\gamma$ expression was significantly enhanced, while IL-4 expression significantly decreased. In addition, in vitro Th1/Th2 polarization experiments revealed that AJ enhanced IFN-$\gamma$ secretion in Th1 cells, but reduced the IL-4 in Th2 cells in dose-dependent manner. Conclusion : These results suggest that AJ treatment could be a desirable alternative therapy for the prevention or correction of Th2 dominant pathological disorders, such as allergy and asthma.