• Title/Summary/Keyword: Suppressive activity

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Antimalarial Effects of Areca catechu L.

  • Jiang, Jing-Hua;Jung, Suk-Yul;Kim, Youn-Chul;Shin, Sae-Ron;Yu, Seung-Taek;Park, Hyun
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.23 no.2
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    • pp.494-498
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    • 2009
  • The emergence and spread of drug-resistant malaria parasites is a serious public health problem in the tropical world. Useful antimalarial drugs such as chloroquine have resistance in the world now. Moreover, other antimalarialdrugs such as mefloquine, halofantrine, atovaquone, proguanil, artemether and lumefantrine retain efficacy but have limitations, one of which is their high cost. New antimalarial drugs are clearly needed now. Cytotoxicity assay and susceptibility assay were performed for the selectivity of herb extracts in vitro. On the basis of high selectivity, 4-day suppressive test and survival test were progressed in Plasmodium berghei-infected mice. The selectivity of Areca catechu L. (ACL) and butanol extract of ACL (ACL-BuOH extract) were 3.4 and 3.0 in vitro, respectively. Moreover in vivo, 4-day suppressive test showed 39.1 % inhibition effect after treated with 150 mg/kg/day ACL-BuOH to P. berghei-infected mice. Survival test also showed 60% survival rate with ACL-BuOH-treated group while all other group mice died. In this study, ACL and ACL-BuOH were investigated for antimalarial activity in vitro and in vivo and they showed a potent antimalarial activity. In particular,ACL-BuOH could specifically lead higher survival rate of mice in vivo. Therefore ACL-BuOH would be a candidate of antimalarial drugs.

Immunosuppressive effects and pathogenicity of a Korean isolate of reticuloendotheliosis virus in chickens (Reticuloendotheliosis virus의 닭에 대한 면역억제효과와 병원성)

  • Han, Myung-guk;Kim, Sun-joong
    • Korean Journal of Veterinary Research
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    • v.40 no.2
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    • pp.311-323
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    • 2000
  • Immunosuppressive effects of reticuloendotheliosis virus (REV) infection in chickens were investigated. Primary antibody responses to Newcastle disease virus (strain B1) and sheep red blood cells were significantly low in chickens inoculated with the local isolate 89-74 of REV compared to those of uninfected chickens. In chickens infected with REV strain T or 89-74, blastogenesis of spleen cells and peripheral blood lymphocytes (PBL) to concanavalin A (Con A) was severely suppressed. When specific pathogen free (SPF) chickens were inoculated with the isolate, the suppressive effect was observed up to 7 weeks of age while, in the contact infected chickens, the suppression was absent. Similar suppressive effects were observed in chickens inoculated with REV strain T at 2, 3 and 4 weeks of age. When spleen cells or PBL from uninfected chickens were co-cultured with spleen cells or PBL from chickens infected with REV at 1 day-old or 2 week-old, the blastogenesis of the normal cells was suppressed. The suppressive effect of PBL from REV-infected chickens on normal lymphocytes was abrogated by the treatment with trypsin. However the suppressive activity of the REV-infected PBL was not influenced at removing machrophage from the cell suspension by incubation in plastic petri dishes. In addition to the immunosuppression, chickens infected with the REV isolate showed abnormal feather development (nakanuke), anemia, paralysis and retarded growth. Three out of 11 chickens inoculated with the isolate at day-old died between 6 and 9 weeks of age by bacterial infections.

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Lactoferrin Induces Tolerogenic Bone Marrow-Derived Dendritic Cells

  • Hui-Won Park;Sun-Hee Park;Hyeon-Ju Jo;Tae-Gyu Kim;Jeong Hyun Lee;Seung-Goo Kang;Young-Saeng Jang;Pyeung-Hyeun Kim
    • IMMUNE NETWORK
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    • v.20 no.5
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    • pp.38.1-38.12
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    • 2020
  • Dendritic cells (DCs) are professional antigen-presenting cells (APCs) that initiate both T-cell responses and tolerance. Tolerogenic DCs (tDCs) are regulatory DCs that suppress immune responses through the induction of T-cell anergy and Tregs. Because lactoferrin (LF) was demonstrated to induce functional Tregs and has a protective effect against inflammatory bowel disease, we explored the tolerogenic effects of LF on mouse bone marrow-derived DCs (BMDCs). The expression of CD80/86 and MHC class II was diminished in LF-treated BMDCs (LF-BMDCs). LF facilitated BMDCs to suppress proliferation and elevate Foxp3+ induced Treg (iTreg) differentiation in ovalbumin-specific CD4+ T-cell culture. Foxp3 expression was further increased by blockade of the B7 molecule using CTLA4-Ig but was diminished by additional CD28 stimulation using anti-CD28 Ab. On the other hand, the levels of arginase-1 and indoleamine 2,3-dioxygenase-1 (known as key T-cell suppressive molecules) were increased in LF-BMDCs. Consistently, the suppressive activity of LF-BMDCs was partially restored by inhibitors of these molecules. Collectively, these results suggest that LF effectively causes DCs to be tolerogenic by both the suppression of T-cell proliferation and enhancement of iTreg differentiation. This tolerogenic effect of LF is due to the reduction of costimulatory molecules and enhancement of suppressive molecules.

Anti-Oxidative and Anti-Inflammatory Activities of Seven Medicinal Herbs including Tetrapanax papyriferus and Piper longum Linne (통초, 필발을 포함한 7종 한약재 추출물의 항산화 및 항염증 활성)

  • Jin, Kyong-Suk;Oh, You Na;Lee, Ji Young;Son, Byung Yil;Choi, Woobong;Lee, Eun-Woo;Kwon, Hyun Ju;Kim, Byung Woo
    • Microbiology and Biotechnology Letters
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    • v.41 no.2
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    • pp.253-262
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    • 2013
  • In this study, we analyzed the anti-oxidative and anti-inflammatory activities of seven medicinal herbs. All extracts of the tested herbs, Euryale ferox Salisbury, Echinops setifer Iljin, Amomum cardamomum Linne, Tetrapanax papyriferus, Illicium verum Hook. f., Typha orientalis Presl, and Piper longum Linne, exhibited potent anti-oxidative activity as confirmed by DPPH radical scavenging capacity. Lipopolysaccharide (LPS) induced nitric oxide (NO) production, in the RAW 264.7 cell line, was also ameliorated by all extracts' treatments in a dose dependent manner. NO suppressive activity originated from the inhibition of inducible nitric oxide synthase (iNOS) protein expression by the extracts. Three extracts, E. ferox S., I. verum Hook. f., and P. longum L., possessed suppressive activity against, not only iNOS, but also cycloxygenase 2 (COX-2) protein expression. These three extracts may then serve as potential candidates for non steroidal analgesic inflammation drugs (NSAIDs). Furthermore, all extracts induced anti-oxidative enzyme, heme oxygenase 1, protein expression. Taken together, these results provide an important new insight into the fact that various medicinal herbs possess potent anti-oxidative and anti-inflammatory activities and might be utilized as promising agents in the field of health products. Further studies for the identification of the active compounds from medicinal herbs are clearly needed.

Screening of Stat3 inhibitory effects of Korean herbal medicines in the A549 human lung cancer cell line

  • Park, Jong-Shik;Bang, Ok-Sun;Kim, Jinhee
    • Integrative Medicine Research
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    • v.3 no.2
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    • pp.67-73
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    • 2014
  • Background: The transcription factor signal transducer and activator of transcription 3 (Stat3)is constitutively activated in many human cancers. It promotes tumor cell proliferation,inhibits apoptosis, induces angiogenesis and metastasis, and suppresses antitumor hostimmune responses. Therefore, Stat3 has emerged as a promising molecular target for cancertherapies. In this study, we evaluated the Stat3-suppressive activity of 38 herbal medicinestraditionally used in Korea.Methods: Medicinal herb extracts in 70% ethanol were screened for their ability to suppressStat3 in the A549 human lung cancer cell line. A Stat3-responsive reporter assay system wasused to detect intracellular Stat3 activity in extract-treated cells, and Western blot analyseswere performed to measure the expression profiles of Stat3-regulated proteins.Results: Fifty percent of the 38 extracts possessed at least mild Stat3-suppressive activities(i.e., activity less than 75% of the vehicle control). Ethanol extracts of Bupleurum falcatumL., Taraxacum officinale Weber, Solanum nigrum L., Ulmus macrocarpa Hance, Euonymus alatusSieb., Artemisia capillaris Thunb., and Saururus chinensis (Lour.) Baill inhibited up to 75% of thevehicle control Stat3 activity level. A549 cells treated with these extracts also had reducedBcl-xL, Survivin, c-Myc, and Mcl-1 expression.Conclusion: Many medicinal herbs traditionally used in Korea contain Stat3 activity-suppressing substances. Because of the therapeutic impact of Stat3 inhibition, these resultscould be useful when developing novel cancer therapeutics from medicinal herbs.

TR4 Inhibits LXR-mediated Decrease of Lipid Accumulation in 3T3-L1 Adipocytes

  • Choi, Ho-Jung;Kim, Eung-Seok
    • Food Science of Animal Resources
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    • v.31 no.3
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    • pp.398-404
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    • 2011
  • TR4 has been suggested to play an important role in lipid metabolism in adipocytes. Although TR4 facilitates lipid accumulation during adipogenesis, the regulatory effect of TR4 on lipid storage in mature adipocytes remains unclear. We showed that TR4 inhibited the LXR agonist GW3965-mediated decrease of lipid accumulation in 3T3-L1 adipocytes. A reporter gene analysis revealed that TR4 suppressed LXR${\alpha}$ transcriptional activity, although LXR${\alpha}$ was unable to affect TR4 transcriptional activity. Moreover, adding TR4 resulted in reduced LXR${\alpha}$ binding to the LXR responsive element in a gel shift assay. Additionally, the suppressive effect of GW3965 on perilipin expression and lipid accumulation in 3T3-L1 adipocytes was abolished by TR4 overexpression. Taken together, our data demonstrate that TR4 plays an inhibitory role in LXR${\alpha}$-mediated suppression of lipid accumulation in 3T3-L1 adipocytes. This TR4 protective effect is mediated, in part, y blocking the suppressive effect of GW3965 on perilipin gene expression.

Structural Features of Polyphenolic Compounds in Their NO Inhibitory Activities

  • Kim, Byung-Hun;Lee, Yong-Gyu;Kim, Tae-Woong;Cho, Jae-Youl
    • Biomolecules & Therapeutics
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    • v.17 no.1
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    • pp.79-85
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    • 2009
  • Polyphenolic compounds are reported to have various pharmacological activities such as anti-oxidative, anti-cancerous, anti-inflammatory and anti-aging effects. Although numerous papers explore their functional roles in many different cellular actions, not many studies handle their structural features in anti-inflammatory responses. In this study, therefore, we examined structural role of substituted transstilbenes in their NO inhibitory and NF-${\kappa}B$ suppressive activities. Of 10 compounds tested, 4 compounds (cinnamic acid, resveratrol, piceatannol and curcumin) displayed NO inhibitory activities in a dose-dependent manner. Similarly, these compounds blocked LPS-induced cytotoxicity of RAW264.7 cells. All NO inhibitory compounds also inhibited $I{\kappa}B{\alpha}$ phosphorylation, a hallmark for NF-${\kappa}B$ activation. However, these inhibitory compounds exhibited distinct suppressive pattern in tumor necrosis factor (TNF)-${\alpha}$- or phorbol-12-myristate-13-acetate (PMA)-induced NF-${\kappa}B$ and AP-1 activation. According to structure-activity relationship study, polarity and size of ring B seem to be important for diminishing NO production. Therefore, our data suggest that substituted trans-stilbenes can be developed as novel anti-inflammatory drug or further developed as lead compounds for another improvement.

A Suppressive Component on Phagocytosis of Murine Peritoneal Macrophage in Aurantii immaturi pericarpium (청피에 함유된 복강 마크로파지의 탐식작용 억제 성분)

  • Eun, Jae-Soon;Kim, Dae-Keun;So, June-No;Zee, Ok-Pyo
    • YAKHAK HOEJI
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    • v.42 no.6
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    • pp.567-571
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    • 1998
  • The phagocytic activity of murine peritoneal macrophage, was determined by lucigenin chemiluminescence and engulfment of fluorescein-conjugated E. coli particle. The acti vity-guided fractionation upon the methylenechloride fraction of Aurantii immaturi pericarpium led to the isolation of a flavonoid, isosinensetin, as a suppressive component of phagocytosis. Isosinensetin suppressed the lucigenin chemiluminescence and the engulfment of fluorescein-conjugated E. coli particles and enhanced the production of nitric oxide in murine peritoneal macrophage.

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The effect of Propolis on Endotoxin-induced thrombosis (Endotoxin에 의한 혈전증에 미치는 Propolis의 효과)

  • 정춘식;정주희;정기화
    • Biomolecules & Therapeutics
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    • v.8 no.3
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    • pp.223-227
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    • 2000
  • Propolis, a natural resinous compound collected from honey bees, contains many biochemical constituents and has been used for traditional medicines as early as 300 B .C. Recently, it has been reported to possess many biological activities such as antibacterial, antiviral, fungicidal, local anaesthetic, immunostimulating, antiinflammatory and free radical scavenging properties. To investigate activities of chrysin, one of propolis effective compounds for blood coagulation system was injected endotoxin (4000 EU/kg, i.v.) in rats at 1 hr after administered chrysin (20 mg/kg, p.o.). This study was resulted that chrysin has antiplatelet aggregation activity in vitro, delay of blood clotting time and prothrombin time, and reduction of fibrinogen and FDP in vivo. Chrysin has increased SOD activity, GSH content and GST activity, and decreased MDA content in liver. The result suggests that the antithrombosis effect of chrysin is suppressive activity for a blood coagulation system and antioxidative activity.

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Effect of Carthamus tinctorius L. Semen on Endotoxin-induced Thrombosis in Rats (Endotoxin에 의한 혈전증에 미치는 홍화자의 효과)

  • 송금람;정기화
    • Biomolecules & Therapeutics
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    • v.9 no.4
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    • pp.258-262
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    • 2001
  • In the advanced age, cardiovascular disease is more serious than any other disease. Especially, the thrombus causes the serious disease like apoplexia, carebri and myocardial infarction. Thrombosis is caused by the injury of endothelium and the alterations in normal blood flow. To investigate activities of Carthamus tinctorius L. Semen butanol fraction for blood coagulation system, endotoxin (4000EU/kg) was injected (i..v) to rats at 1hr after administration of Carthamus tinctorius L. Semen butanole fraction (500 mg/kg, p.o.). Carthamus tinctorius L. Semen butanol fraction was found to have antiplatelet activity in vitro. In vivo it showed a delay of blood clotting time, and prothrombin time, and reduction of fibrinogen and FDP It also increased SOD activity, and decreased MDA content. These results suggest that the antithrombosis effect of Carthamus tinctorius L. Semen butanol frac tion results from suppressive activity for a blood coagulation system and antioxidative activity.

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