• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2002.05a
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• pp.75-75
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• 2002

• Korean Journal of Environmental Biology
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• v.21 no.3
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• pp.308-312
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• 2003

Various pesticides known or suspected to interfere with steroid hormone function were screened toy effects in leydig cells on catalytic activity and mRNA expression of aromatase. Dichlorodiphenyltrichloroethane (DDT) is a widespread environmental pollutant. In this study, we investigated the effect of DDT on testosterone production through aromatase activity and its molecular mechanism in testicular leydig cell, R2C by using radioimmunoassay (RIA). As the results, the potent leydig: cell activator LH increased testosterone production compared to the control. DDT exposure significantly decreased testosterone production in R2C cell. In addition, DDT was found to increase aromatase gene expression and activity in R2C cell in a dose dependent manner. In order to assess whether the suppressive effects of DDT on LH-inducible testosterone (T) production might be influenced by the ER, ICI 182.780 was used, and it was found that these inhibitory effects of DDT were antagonized by ICI 182.780, implying that the estrogen receptor (ER) mediates the suppressive effects of DDT. Furthermore, the inducible effects of DDT on aromatase gene expression might be influenced by the ER, ICI 182.780 was used, and it was found that these enhancing effects of DDT were antagonized by ICI 182.780, implying that the ER mediates the inducible effects of DDT. Our results indicated that DDT inhibition of luteinizing hormone (LH) -inducible T production in R2C cell is mediated through aromatase. However, the precise mechanisms by which DDT enhance in R2C cell remains unknown. The current study suggests the possibility that DDT might act as a modulator aromatase gene transcription.

• The Journal of Internal Korean Medicine
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• v.24 no.2
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• pp.290-299
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• 2003

Background : Nowadays many researches about it s cure are going on world widely since cancer is one of the most human health threatening diseases. In Chinese and North Korean medicine, Duchesnea india(Audra.) Foche. is practically used to treat many kinds of cancer, but in Korea it is rarely used. So, we need to scientifically identify anti-tumor effects of Duchesnea india(Audra.) Foche. Objective : We are aimed to identify anti-tumor effects of Duchesnea india(Audra.) Foche. on the stomach cancer cells through molecular biologic methods. Material & Methods : We used AGS as stomach cancer cells from American Type Culture Collection. We added the boiled extract of Duchesnea india(Audra.) Foche. $5{\mu}l$(Sample I), $10{\mu}l$(Sample II) to cultural media(ml)for 0,6, 12, 24, 48 hours. We measured the killing effect on stomach cancer cells through Tryphan blue exclusion test and the suppressive effect on viability of stomach cancer cells via MTT assay. the quantitative RT-PCR was used to examine their effect on the revelation of Bcl-2, Bcl-XL, and Bax, which are genes related to apoptosis. We measured change of mitochondria membrane permeability and membrane potential via flow cytometry. Result : 1. The killing effect on stomach cancer cells showed that each test groups killed more stomach cancer cells than the control group with a time(6 hours later) and density dependent manner, which was statistical significance. 2. The suppressive effect on viability of stomach cancer cells showed that each test groups had more suppressive effects on viability of stomach cancer cells than the control group with a time(6 hours later), which was statistical significance. 3. In the test about the revelation of genes related to apoptosis, the revelation of Bcl-2 and Bcl-XL decreased with a density manner which was statistical significance. but the revelation of Bax was not changed with statistical significance. 4. As a result of this test, Duchesnea india(Audra.) Foche. caused apoptosis by decreasing the absorbance of mitochondria with statistical significance. and also induced apoptosis by decreasing the membrane potential of mitochondria. Conclusion : This experiment showed that Duchesnea india(Audra.) Foche. has anti-tumor effect with statistical significance. This is in vitro experiment and basic experiment on Duchesnea india(Audra.) Foche. We hope more progressive researchs on Duchesnea india(Audra.) Foche. will go on and its anti-tumor effects will be more practically identified.

• Toxicological Research
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• v.22 no.3
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• pp.267-273
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• 2006

Tungtungmadic acid(3-caffeoyl, 4-dihydrocaffeoyl quinic acid: CDCQ) is a new chlorogenic acid derivative isolated from the Salicornia herbacea. The suppressive effects of CDCQ on the progress of acute carbon tetrachloride($CCl_4$)-induced hepatic fibrosis were investigated in mice. CDCQ significantly suppressed $CCl_4$-induced hepatic necrosis and inflammation, as determined by serum enzymatic activities of alanine and aspartate aminotransferase and serum TNF-$\alpha$ levels in a dose-dependent manner. In addition, increased hepatic lipid peroxidation and fibrosis after acute $CCl_4$ treatment were suppressed by the administration of CDCQ. CDCQ also significantly prevented the elevation of hepatic hydroxyproline and collagen content and ${\alpha}$-smooth muscle actin(${\alpha}$-SMA) expression in the liver of $CCl_4$-intoxicated mice. These results suggest that the suppressive effects of CDCQ against the acute $CCl_4$-induced hepatic fibrosis possibly related to its ability to block both hepatic inflammation and the activation of hepatic stellate cells.

• Journal of Applied Biological Chemistry
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• v.50 no.3
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• pp.155-159
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• 2007

The water extracts of root, stem, and leaf from Korean indigenous Acanthopanax divaritacus were examined for their suppressive effects against allergic inflammations such as lipoxygenase activity, ${\beta}-hexosaminidase$ release, inflammatory cytokine production, and serum IgE level. The root extract inhibited the release of ${\beta}-hexosaminidase$, a degranulation marker, from rat basophilic leukemia cells (RBL-2H3) much more potently than the stem and leaf extracts. The root extract also significantly reduced the expression of $TNF-{\alpha}\;and\;IL-1{\beta}$ in the RBL-2H3 cells challenged with antigen. Moreover, there was a significant fall in the serum IgE level by the treatment of the root extract. Taken together, the root extract could be the most potent inhibitor of allergic inflammation, suppressing ${\beta}-hexosaminidase$ release and inflammatory cytokine expression, as well as reducing the rise of serum IgE level.

• Research in Community and Public Health Nursing
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• v.26 no.1
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• pp.11-17
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• 2015

Purpose: This study was to ascertain whether there are differences in health care utilization and expenditure for Type I Medical Aid Beneficiaries before and after applying Copayment. Methods: This study was one-group pretest posttest design study using secondary data analysis. Data for pretest group were collected from claims data of the Korea National Health Insurance Corporation and data for posttest group were collected through door to-door interviews using a structured questionnaire. A total of 1,364 subjects were sampled systematically from medical aid beneficiaries who had applied for copayment during the period from December 12, 2007 to September 25, 2008. Results: There was no negative effect of copayment on accessibility to medical services, medication adherence (p=.94), and quality of life (p=.25). Some of the subjects' health behaviors even increased preferably after applying for copayment including flu prevention (p<.001), health care examination (p=.035), and cancer screening (p=.002). However, significant suppressive effects of copayment were found on outpatient hospital visiting days (p<.001) and outpatient medical expenditure (p<.001). Conclusion: Copayment does not seem to be a great influencing factor on beneficiaries' accessibility to medical services and their health behavior even though it has suppressive effects on outpatients' use of health care.

• Food Science and Biotechnology
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• v.16 no.1
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• pp.43-48
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• 2007

Collagen-induced arthritis (CIA) is a model for some types of human autoimmune rheumatoid arthritis (RA). In this study, we examined whether ethanol extract of potato (Solanum tuberosum) is efficacious against CIA in mice. Potato extracts (100 and 200 mg/kg) were orally administered to DBA/1J mice once daily for 49 day after initial immunization with type II collagen. Clinical assessment of disease and measurement of paw edema were conducted throughout the study. The production of CIA-related rheumatoid factor, anti-type II collagen antibody, and cytokines were examined in DBA/1J mice. Serum levels of AST, ALT, creatinine, and lipids were measured, and antioxidant enzyme activity in the spleen was also determined. The arthritis score and paw edema were markedly suppressed in the groups treated with potato extract. Levels of rheumatoid factor, anti-type II collagen antibody, interleukin (IL)-1, IL-6, LDL-cholesterol, and malondialdehyde in sera were also reduced by potato extract treatment. The activities of glutathione peroxidase and glutathione reductase were increased in the spleens of CIA mice treated with potato extract. These findings suggest that potato extract has suppressive effects on type II collagen-induced arthritis, an animal model for human RA.

• The Korean Journal of Physiology and Pharmacology
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• v.12 no.5
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• pp.281-286
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• 2008

Although the interaction between gp130 and the ErbB family has frequently been shown in cancer cells, the mechanism of this interaction remains unclear and controversial. In the present study, we found that specific tyrphostin inhibitors of ErbB2 (AG825 and AG879), but not ErbB1 inhibitor (AG1478), suppressed IL-6-induced tyrosine phosphorylation of STAT3 in schwannoma cells. However, biochemical evidence for transactivation of ErbB2 by IL-6 was not observed. Additionally, the inhibition of ErbB2 expression, with either a specific RNAi or transfection of an ErbB2 mutant lacking the intracellular domain did not inhibit the IL-6-induced tyrosine phosphorylation of STAT3. Thus, it seems that tyrphostins, which are known as specific inhibitors of the ErbB2 kinase, may have non-specific suppressive effects on the IL-6/STAT3 pathway.

• Toxicological Research
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• v.16 no.4
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• pp.317-323
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• 2000

The immunosuppressive effects of thirty nine chemicals chosen by their potential toxicity were evaluated using a three-step testing method. The immunotoxicity test method developed in this study consisted of three simple assays of lymphoproliferation, mixed leukocyte response, and interleukin (IL)-2 production. The first step was mitogen-induced proliferation assay. Ten chemicals showed the inhibitory effects on the mitogen (lipopolysaccharide or concanavalin A)-induced proliferation in dose-dependent manners. The second step was mixed lymphocyte response. This step crosschecked the growth-suppressive effects detected at the first step. All of 10 chemicals, which showed suppression of lymphoproliferation, also exhibited the suppressive effects on the mixed lymphocyte response in the similar range of chemical concentration. The third step was planned to determine whether or not this growth suppression was mediated through an early activation of T-cell, which could be represented with IL-2 production. Six out of 10 chemicals decreased the interleukin-2 production in the similar concentration range used in the step 1 and 2. These results suggest that those 6 chemicals might have their targets on the signal transduction path-way toward the IL-2 production. In the meantime the other 4 chemicals might have their targets after the IL-2 production signal. Taken all together, the three-step test would be simple, fast, and efficient to deter-mine whether or not the chemical has immunosuppressive effects.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.1
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• pp.39-49
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• 2007

Rheumatoid arthritis is an autoimmune disease involving multiple joint. In order to access the suppressive effects of JTT on rheumatoid arthritis and it's effects on immune system we investigated whether JTT could suppress the disease progression of collagen-induced arthritis. DBA/1 mice were immunized with bovine type II collagen. After a second collagen immunization, mice were treated with DW, JTT (200 or 400 mg/kg) or methotrexate (MTX, 30 mg/kg) as a positive control. Oral administration of JTT significantly suppressed the progression of CIA, which extend is comparable to that of MTX. Histological examination reveled that JTT inhibited infiltration of inflammatory cells into affected paw joint and bone erosion and cartilage destruction were greatly reduced compared with control. Total cell number of spleen, lymph node and peripheral blood were significantly reduced. The absolute number of CD19$^+$, CD3$^+$/CD69$^+$, CD4$^+$/CD25$^+$ cell in spleen from JTT treated mice were significantly decreased. The absolute number of CD19$^+$, CD3$^+$, CD3$^+$/CD69$^+$, CD4$^+$, CD4$^+$/CD25$^+$ CD8$^+$, CD49b, CD3/CD49b cells in draining lymph node were significantly increased compared with control. In peripheral blood mononuclear cells of JTT treated mice, the absolute number of CD4$^+$, CD4$^+$/CD25$^+$, CD3$^+$/CD69$^+$ cells were significantly decreased compared with control, while that of CD49b$^+$ was slightly increased. Infiltration of CD3$^+$ cells and CD11b$^+$/Gr-1$^+$ cells into paw joint was significantly reduced in JTT treated mice. The levels of pathologic cytokines including TNF-a and IL-6 in serum were significantly decreased by oral treatment with JTT The levels of IFN-g in the culture supernatant of splenocyte stimulated with CD3$^+$/CD28$^+$ or collagen were dramatically decreased, while the levels of IL-4 was increased under CD3$^+$/CD28$^+$ or collagen stimulation. Rheumatoid factors including IgG, IgM and collagen specific antibody were present much lower in the serum of JTT treated mice than control. Taken together, JTT has suppressive effects on rheumatoid arthritis by modulating immune system, and has potential to use anti-rheumatic arthritic agent in human.