• 약학회지
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• 제51권4호
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• pp.270-276
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• 2007

Silybin is known to be a major active flavonoid component isolated from Silybum marianum, a hepatoprotective medicinal plant. In this study, we examined the immunomodulatory role of silybin on T cell and macrophage-mediated immune responses. To do this, the proliferation of splenic lymphocytes and CD8+ CTLL-2 cells under mitogenic stimulation with lipopolysaccharide (LPS), concanavalin (Con) A and interleukin (IL)-2 and the production of $TNF-{\alpha}$ and NO from LPS- and $IFN-{\gamma}$-activated macrophages was evaluated under silybin treatment. The mitogenic proliferation of splenic lymphocytes induced by LPS and Con A was strongly diminished by silybin in a dose-dependent manner. Moreover, the proliferation of CD8+ CTLL-2 cells was also negatively modulated by the compound. In contrast, silybin did not strongly suppress the proliferation of normal splenocytes and T cell line Sup-T1 cells, indicating that the inhibitory effect of silybin may be due to blocking only mitogenic responses of splenic lymphocytes. In addition, silybin inhibited $TNF-{\alpha}$ production in LPS-stimulated RAW264.7 cells. Effect of silybin however was distinct, according to NO-inducing stimuli. Thus, silybin only blocked NO production induced by $IFN-{\gamma}$ but not LPS and the inhibition was increased when PMA was co-treated with $IFN-{\gamma}$. Unlike NO inhibition, however, this compound protected the cytotoxic damage of RAW264.7 cells induced by both LPS and $IFN-{\gamma}$. Therefore, our data suggest that silybin may participate in host immune responses mediated by T cells and macrophages via regulating mitogenic proliferation, and the production of $TNF-{\alpha}$ and NO, depending on cellular stimuli.

• Molecules and Cells
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• 제20권3호
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• pp.378-384
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• 2005

Estrogen metabolites are carcinogenic. The comparative mitogenic activities of $17{\beta}$-estradiol (E2) and four metabolites, 2-hydroxyestradiol (2-OHE2), 4-hydroxyestradiol (4-OHE2), $16{\alpha}$-hydroxyestrone ($16{\alpha}$-OHE1) and 2-methoxyestradiol (2-ME), were determined in estrogen receptor(ER)-positive MCF-7 human breast cancer cells. Each of the E2 metabolites caused proliferation of the MCF-7 cells, but only E2 and $16{\alpha}$-OHE1 induced a greater than 20-fold increases in transcripts of the progesterone receptor (PR) gene, a classical ER-mediated gene. This suggests that the mitogenic action of E2 and $16{\alpha}$-OHE1 could result from their effects on gene expression via the ER. E2 metabolites altered the expression of E2-regulated proteins including heat shock proteins (Hsps). $16{\alpha}$-OHE1 and 2-ME as well as E2 increased levels of Hsp56, Hsp60, $Hsp90{\alpha}$ and Hsp110 transcripts, and the patterns of these inductions resembled that of PR. Hsp56 and Hsp60 protein levels were increased by all the E2 metabolites. Levels of the transcripts of 3 E2-upregulated proteins (XTP3-transactivated protein A, protein disulfide isomerase-associated 4 protein and stathmin 1) and an E2-downregulated protein (aminoacylase 1) were also affected by the E2 metabolites. These results suggest that the altered expression of Hsps (especially Hsp56 and Hsp60) by E2 metabolites such as E2, $16{\alpha}$-OHE1 and 2-ME could be closely linked to their mitogenic action.

• 한국동물학회지
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• 제33권3호
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• pp.266-275
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• 1990

Onocogene의 일종인 c-raf protein kinase는 세포질 속에 존재하는 serine / threonine-speccific protein이며, 이것은 mitogene signal에 의해 활성화된다. c-raf protein kinase의 구조와 기능은 protein kinase C와 매우 유사한 것으로 생각된다. 면역세포화학적으로 c-raf protein kinase의 signal transduction을 조사하기 위하여 EC-4 세포에 tumor promotor인 12-0-tet-radecanoylphorbol-13-acetae와 mitogenic gactor인 platelet-derived growth factor로 time-course에 따라서 처리하였다. Translocotion되는 c-raf는 먼저 perinuclear membrane에 모이고 그 후에 핵내로 이동되었다. 그런데 TPA와 PDGF로 처리한 c-raf의 translocotion은 각각의 다른 경로를 가짐을 알 수 있었다. TPA와 PAGF을 장기간 처리하였을 때, c-raf protein kinase의 down regulation이 유도됨을 알 수 있었다.

• Archives of Pharmacal Research
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• 제13권4호
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• pp.330-337
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• 1990

The crude polysaccharide from Panax ginseng prepared by hot water extration and precipiation with ethanol was further fractionated into neutral and acidic fractions by DEAE- cellulose ion exchange chromatography. The chemical compositions were 85.0% carbohydrorate and 15.0% protein for the neutral fraction, and 28.4% carbohydrate, 10.0% protein and 29.0% uronic acid for the acidic fraction. The acidic fraction was more effective in increasing of the ratio of spleen to body weight, the number of antibody secreting cells to SRBC and phagocytic activity of reticuloendothelial system, as well as antitumor activity against the solid form of sarcoma 180 in ICR mice than the neutral fraction. All polysaccharide fractions were mitogenic to cultured spleen cells of C57BL/6 mice. However, FA was different from FN in the co-mitogenicities with lectin mitogens. Both crude and acidic fractions potentiated remarkably the mitogenic activity of PHA-P or LPS in dose-dependent manner but neutral fraction enhanced only that of LPS. Three polysaccharide fractions had no effect on that of Con A. These results suggest that the acidic fraction may stimulate B and Td cells as well as macrophages while the neutral fraction may simulate only B cells and macropages.

• 대한치과교정학회지
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• 제27권6호
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• pp.955-961
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• 1997

흡연의 주성분중의 하나인 니코틴은 인체내에 다양한 전신적 및 국소적인 질환의 원인으로 보고 되어지고 있다. 전신적인 질환에 있어 특히, 호흡기와 순환기 조직세포에 대한 세포분열효과가 많은 연구의 초점이 되어왔으며, 국소적인 효과에 대한 연구에서는 조직파괴나 치료후 치유지연에 대해 보고하고 있다. Platelet-Derived Growth Factor(PDGF)와 Insulin-like Growth Factor(IGF)는 치주인대세포의 세포분열을 촉진하는 주요 성장인자로 알려져있다. 본 연구의 목적은 니코틴이 사람의 치주인대세포에 미치는 세포분열효과를 알아보기 위하여 니코틴 처리된 치주인대세포로부터 추출한 PDGF-${\alpha}\;and\;{\beta}$ receptor 및 IGF-l 수용기의 mRNA변화를 Northern분석을 이용해 확인해 보고자 함이다. 실험군은 각기 다른 농도의 니코틴(100ng/ml, 1000mg/ml)과 배양액내 혈청농도($1\%,\;10\%$)로 나누었으며 이를 각각 니코틴 처리 시간에 따라 분류하였다. 본연구의 결과로 $10\%$ 혈청의 배양액과 100ng/ml 니코틴 농도군에서 모든 성장인자 수용체의 mRNA가 증가됨을 보였으며 이는 흡연자의 체내 축적 가능한 니코틴 농도에서 치주인대세포의 세포분열을 촉진한다는 추측을 가능케 한다.

• Journal of Photoscience
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• 제9권2호
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• pp.433-435
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• 2002

In the present study, we investigated the actions of sphingosine-I-phosphate (SPP) in Mel-Ab melanocytes. We observed the cytoprotective effect of SPP on UVB-induced cell death. Following exposure of cells to UVB, a significant protective effect was seen in cultures pretreated with SPP. Since SPP is well known as a mitogenic agent, it is possible that the mitogenic effect of SPP may contribute to cell survival. Surprisingly, we found that SPP inhibited DNA-synthesis significantly. We were next interested in the regulation of the extracellular signal-regulated protein kinase (ERK) and Akt pathways by SPP. We clearly observed that SPP potently stimulated the phosphorylation of both ERK and Akt against UVB-induced cell death. Based on these results, we conclude that SPP may show its cytoprotective effect through ERK and Akt activation.

• Journal of Ginseng Research
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• 제13권2호
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• pp.215-222
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• 1989

A macromolecular fraction from fresh ginseng root containing mainly polysaccharide showed mild mitogenic activity in human cord blood lymphocytes. 2) When lymphocytes were transformed by Con A or PHA, this fraction could greatly enhance the activity of these lectin mitogens, thus showing a potentiation effect. 3) Although this macromolerular fraction contains saponin and is susceptible to trypsin digestion, it is probably a peptido-glycan in nature on account of its important carbohydrate content and thermal stability. 4) This fraction could not support cancer cell (EAT, K562) growth : its inhibitory effect on these cells remains to be explored.

• Journal of Microbiology and Biotechnology
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• 제9권2호
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• pp.163-167
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• 1999

An acidic polysaccharide H-III was extracted from fruiting bodies of Lyophyllum shimeji with hot water. Acid hydrolysis and gas chromatography analysis showed that the polysaccharide was almost exclusively composed of glucose with a very small amount of mannose and galactose. Uronic acid of 8.36% was also detected in H-Ill. Its molecular weight was estimated to be $1{\times} 10^6 Da.\;By\;^{13}C-NMR$ analysis, some repeating units of disaccharide were detected in the polymer H-III. The polysaccharide showed a strong mitogenic activity in a dose-dependent manner.

• 약학회지
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• 제39권3호
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• pp.252-259
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• 1995

Isolation, purification and characterization of biophysicochemical properties of the three new lectins, MLA-I, MLA-II, MLA-III from the hemolymph of Meretrix lusoria have been reported previously. A series of immunochemical studies were investigated in this work. The three lectins were revealed as having partial identity each other by immunodiffusim and immunoelectrophoresis. These results suggest that MLA lectins are isolectins having similar biophysicochemical properties. Particularly, MLA-I proved to be a potent mitogen for murine splenic as well as human peripheral lymphocytes, and the optimum mitogenic dose were 62.5 and 1.95 $\mu\textrm{g}$/ml, respectively.

• 약학회지
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• 제39권3호
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• pp.260-267
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• 1995

A lectin from the edible mushroom, Lentinus edodes, was purified through physiological saline extraction, ammonium sulfate fractionation and column chromatographies. On polyacrylamide gel electrophoresis, 0.05M fraction from hydroxyapatite column exhibited adjacent four sharp bands. The partially purified lectin agglutinated the erythrocytes of rabbit, mouse and rat, but not agglutinated human erythrocytes. The lectin's mitogenic effects were tested by its application to human and murine splenic lymphocytes. The results showed that the 0.05M fraction from hydroxyapatite was mitogenic, and the optimal dose of Lentinus edodes lectin was slightly lower than Con A by the culture with murine splenic and human peripheral lymphocytes. Meanwhile, its ability to agglutinate transformed cells was tested by its administration to continuous cell lines L1210 and HeLa cells. The leetin was found to be an agglutinin of tumor cell lines tested by L1210 and HeLa cells.