• Molecules and Cells
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• v.37 no.5
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• pp.418-425
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• 2014

Extracellular hypotonic stress can affect cellular function. Whether and how hypotonicity affects immune cell function remains to be elucidated. Macrophages are immune cells that play key roles in adaptive and innate in immune reactions. The purpose of this study was to investigate the role and underlying mechanism of hypotonic stress in the function of bone marrow-derived macrophages (BMDMs). Hypotonic stress increased endocytic activity in BMDMs, but there was no significant change in the expression of CD80, CD86, and MHC class II molecules, nor in the secretion of TNF-${\alpha}$ or IL-10 by BMDMs. Furthermore, the enhanced endocytic activity of BMDMs triggered by hypotonic stress was significantly inhibited by chloride channel-3 (ClC-3) siRNA. Our findings suggest that hypotonic stress can induce endocytosis in BMDMs and that ClC-3 plays a central role in the endocytic process.

• IMMUNE NETWORK
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• v.12 no.6
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• pp.253-260
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• 2012

${\alpha}$-Mangostin is a xanthon derivative contained in the fruit hull of mangosteen (Garcinia mangostana L.), and the administration of ${\alpha}$-Mangostin inhibited the growth of transplanted colon cancer, Her/CT26 cells which expressed Her-2/neu as tumor antigen. Although ${\alpha}$-Mangostin was reported to have inhibitory activity against sarco/endoplasmic reticulum $Ca^{2+}$ ATPase like thapsigargin, it showed different activity for autophagy regulation. In the current study, we found that ${\alpha}$-Mangostin induced autophagy activation in mouse intestinal epithelial cells, as GFP-LC3 transgenic mice were orally administered with 20 mg/kg of ${\alpha}$-Mangostin daily for three days. However, the activation of autophagy by ${\alpha}$-Mangostin did not significantly increase OVA-specific T cell proliferation. As we assessed ER stress by using XBP-1 reporter system and phosphorylation of $eIF2{\alpha}$, thapsigargin-induced ER stress was significantly reduced by ${\alpha}$-Mangostin. However, coadministration of thapsigargin with ${\alpha}$-Mangostin completely blocked the antitumor activity of ${\alpha}$-Mangostin, suggesting ER stress with autophagy blockade accelerated tumor growth in mouse colon cancer model. Thus the antitumor activity of ${\alpha}$-Mangostin can be ascribable to the autophagy activation rather than ER stress induction.

• Archives of Pharmacal Research
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• v.25 no.2
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• pp.158-164
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• 2002

In the course of searching immunomodulators from natural sources, the protein-bound polysaccharide, CM-Ala, has been isolated from the water extract of Chelidonium majus L. (Papaveraceae). The immunostimulatory characteristics have been investigated in several experiments such as generation of activated killer (AK) cells, proliferation of splenocytes, activation of macrophages and granulocyte macrophage-colony forming cell (GM-CFC) assay. Of the fractions obtained using Sephacryl S200 column chromatography, CM-Ala was the most effective fraction that augmented the cytotoxicity against Yac-1 tumor cells from 0.88% to 34.18% by culturing with splenocytes for 5 days. CM-Ala also enhanced nitric oxide production by two fold in peritoneal macrophages and exhibited antitumor activity. It showed mitogenic activity on both spleen cells and bone marrow cells. CM-Ala induced proliferation of splenocytes by 84 fold and increased GM-CFC numbers by 1.48 fold over than the non-treated. On the contrary, CM-Ala had cytotoxic activity to a diverse group of tumor cells. From the above results, we proposed that CM-Ala has a possibility of an effective antitumor immunostimulator.

• Archives of Pharmacal Research
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• v.25 no.4
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• pp.457-462
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• 2002

Oregonin, a diarylheptanoid derivative from Alnus hirsuta Turcz, Betulaceae, was evaluated for its antitumor activity. Oregonin, known to have an antitumor function, and is a novel immunomodulator, which may augment macrophage activity. MTT assays and NO production tests were performed in order to investigate the cytotoxicity of oregonin in tumor cells and to examine its influence on macrophage in detail. In this study, the tumoricidal activity was also evaluated by a MTT assay. The cytotoxicity measurements in the oregon in-treated group both in vitro and in vivo showed a significant difference from that of the control group. In vivo, oregonin significantly increased NO production in a dose-dependent manner, and in vitro, the thioglycolate-induced inflammatory macrophages increased NO production in a dose-dependent manner after incubation. These results suggest that oregonin reacts with both the inflammatory and non-inflammatory macrophages in a similar way.

• Proceedings of the PSK Conference
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• 2000.10a
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• pp.179.2-179.2
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• 2000

• Proceedings of the PSK Conference
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• 2001.04a
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• pp.166.2-167
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• 2001

• Proceedings of the Korean Society of Life Science Conference
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• 2007.10a
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• pp.87.1-87.1
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• 2007

See Full Text

• Journal of Life Science
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• v.16 no.2 s.75
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• pp.360-364
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• 2006

Fibrin clots of blood vessels are one of the serious factor caused cardiovascular disease. The development of a antithrombotic and thrombolysis solvent is necessary to prevent and treat these diseases. It has been reported that a strong fibrin-specific fibrinolytic enzyme was produced from a Korean fermented soybean paste similar to Japanese miso. We have been screened the known or novel fibrinolytic enzymes by activity-based and sequence-based screening from soil DNA metagenome library containing all kinds of environmental genomic DNA. The activity-based screening was determined the protease activity on 0.5% skim milk. For sequence-based screening, we designed a set of primer expanding gene sequence of fibrinolytic enzyme, performed PCR and selected clones showing the expected size of amplicons from metagenome library. Transformation of the gene encoding fibrinolytic enzyme was carried out with commercial vectors and their transformants were selected. Finally, we found 15 positive clones from metagenome library. Then each of sequences were analyzed and identified as similar or known the clones of nattokinase. We are going to perform full sequence of each clones, ligate with expression vector, transform into competent cells and then determine activity of expressed enzymes.

• Archives of Pharmacal Research
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• v.18 no.6
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• pp.396-401
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• 1995

As a part of trials to develop the antitumor agent from tannins isolated from plants, the antitumor activity of peduculagin, an ellagitannin, isolated from Alnus hirsuta var. microphylla was examined in vitro and in vivo. In vitro, the cytotoxicity was determined by 0.4% typanblue dye exclusion method. peduculagin showed the dose-dependent cytotoxicity against human chronic myelogenous leukemia (K-562), human promyelocytic leukemia (HL-60), mouse lymphoid neoplasm (P388), mouse lymphocytic leukemia (L1210) and mouse sarcoma 180(S180) cell lines. $ED_{50}\; values\; (ED_{50})$ of each cell line were 5.30, 0.92, 2.78, 9.35 and $1.38 \mug/ml$ respectively. The most sensitive cell line was HL-60. In vivo, pedunculagin was administered to ICR mouse with the doses of 50 and $100{\;}{\mu}g/ml$intraperitoneally once at 20 days before S180 inoculation. peduculagin showed the antitumor activity and its T/C ratio (%) was 120.82% in the group of both concentrations.

• IMMUNE NETWORK
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• v.4 no.2
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• pp.94-99
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• 2004

Background: We previously reported that ginsan, a polysaccharide extracted from Panax ginseng had an immunostimulatory activity such as mitogenic activity, activation of macrophages and killer cells, and production of a variety of cytokines which resulted in antitumor and antiseptic effects. We further purified $\alpha$-(1$\longrightarrow$6)-glucan and $\beta$-(2$\longrightarrow$6)-fructan from the ginsan with size exclusion and ion-exchange column chromatography successively. In this study, we performed the structure-based activity of ginsan by comparison with known polysacchrides such as $\beta$-glucan, curdlan, laminarin, levan, dextran, lentinan and OK-432. Methods: To investigate the immunostimulatory activity of several polysaccharide compounds, we investigated the stimulation of lymphocytes proliferation, the generation of activated killer cells and the secretion of nitrites from activated macrophages. Results: Of polysaccharides tested, curdlan and ginsan stimulated lymphocyte proliferation, suggesting that the molecular weight and composition of polysaccharide are dependent on the mitogenic activity. The production of nitric oxide was significantly increased in curdlan, levan, ginsan and its fraction, indicating that fructan has also capacity to activate macrophages and may devote to kill pathogens. In addition, the activation of macrophages was seemed to be independent of molecular weight of polysaccharide. The generation of AK cells was exhibited in order of curdlan, OK-432> F1, ginsan, F3> levan> etc. The AK activity may be dependent on molecular weight and composition of polysaccharides. Conclusion: Unfortunately, purified polysaccharide from ginsan were less active on immunostimulatory activity than mixed compounds of polysaccharides. From the viewpoint of structure and activity relationships, we found several characteristic features.