• Title/Summary/Keyword: suppressive effects

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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.

The Relationship between Perceived Discrimination and Depression in Korean Canadian College Students: Moderating Effects of Coping Strategies, Cultural Identity and Bicultural Self-Efficacy (재캐나다 한국인 대학생의 지각된 차별감과 우울의 관계: 대처양식 및 문화 정체성과 이중문화 자기효능감의 조절효과)

  • Anna(OAN NA) Lee ;Sung Moon Lim
    • Korean Journal of Culture and Social Issue
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    • v.21 no.3
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    • pp.511-534
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    • 2015
  • The primary goal of the present study was to examine the moderating effects of coping strategies, cultural identity, and bicultural self-efficacy on the relationship between perceived discrimination and depressive symptoms of Korean Canadian college students. Data were collected from 214 Korean Canadian college students studying in Canada through an online and offline survey. A direct effect of perceived discrimination on depressive symptoms and the moderating effects of coping strategies on the relationship between perceived discrimination and depressive symptoms were examined by using hierarchical regression analysis. And three-way interaction of perceived discrimination, coping strategies, and cultural identity, and perceived discrimination, coping strategies, and bicultural self-efficacy on depressive symptoms were examined. Results from a hierarchical regression indicated that perceived discrimination significantly predicted depressive symptoms and this finding is in line with previous studies. Second, reflective, suppressive, and reactive coping strategies did not moderate the relationship between perceived discrimination and depressive symptoms. Third, the three-way interaction effect of perceived discrimination, suppressive coping strategy, and heritage identity predicted the depressive symptoms. Low heritage identity, high level of perceived discrimination and the frequent use of suppressive coping strategy increased the level of depressive symptoms. Fourth, the three-way interaction effect of perceived discrimination, coping strategies, and bicultural self-efficacy did not predict the depressive symptoms. Limitations and applied implications of the results are discussed.

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The Suppressive Effects of Daebangfung-tang against Disuse Muscle Atrophy in Gastrocnemius of Rats (대방풍탕의 흰 쥐 비복근 불용성 근위축에 대한 억제 효과)

  • Kim, Jae Hoon;Lee, Jung Hee;Lee, Cho In;Lee, Bong Hyo;Lee, Yun Kyu;Lee, Hyun-Jong;Kim, Jae Soo
    • Korean Journal of Acupuncture
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    • v.37 no.4
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    • pp.262-270
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    • 2020
  • Objectives : The aim of this study is to evaluate the effect of Daebangfung-tang (DBFT) on suppressing muscle atrophy followed by immobilization. Methods : Twenty young male Sprague-Dawley rats were randomized into two groups. The rats in experimental group (DBFT group) were orally administrated DBFT once a day for 2 weeks, and the rats in control group were given normal saline in the same manner. The immobilization on left leg was carried out using casting tape. The morphologies of gastrocnemius in both groups were assessed. The cross sectional area of them was measured by image analyzer. Immunohistochemical staining was implemented and the numbers of immunopositive cells implying the expression of TNF-α were measured and quantified. Results : DBFT represented the significant suppressive effects against the weight loss of the left gastrocnemius muscle and the reduction in cross sectional area of the left gastrocnemius muscle compared with normal saline. Also the treatment with DBFT significantly reduced the expression of TNF-α in gastrocnemius compared with normal saline. Conclusions : DBFT is thought to have the significant suppressive effect against muscle atrophy followed by immobilization.

Suppressive effects of Morus alba Linne Root Bark (MRAL) on activation of MC/9 mast cells (상백피에 의한 MC/9 비만세포의 활성 억제 조절 연구)

  • Lee, Ki Jeon;Kim, Bok Kyu;Kil, Ki Jung
    • The Korea Journal of Herbology
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    • v.28 no.1
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    • pp.33-42
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    • 2013
  • Objective : Morus alba Linne Root Bark (MRAL) is a medicinal herb in Korean Medicine, known for its anti-inflammatory and anti-allergic properties. However, its mechanisms of action and the cellular targets have not yet been found and the study was developed to investigate the allergic suppressive effect of MRAL. The purpose of this study is to investigate the allergic suppressive effects of MRAL on activation of MC/9 mast cells. Methods : Cytotoxic activity of MRAL (50, 100, 200, 400 ${\mu}g/mL$) on MC/9 mast cells measured using EZ-Cytox cell viability assay kit (WST reagent). The levels of interleukin-5 (IL-5), IL-13 and IL-4, IL-5, IL-6, IL-13 mRNA expression were measured by enzyme-linked immunosorbent assay (ELISA) and real-time PCR respectively. The expression of transcription factors such as GATA-1, GATA-2, NFAT, AP-1 and NF-${\kappa}B$ p65 DNA binding activity were measured by western blot and electrophoresis mobility shift assay (EMSA). Results : Our results indicated that MRAL (50 ${\mu}g/mL$, 100 ${\mu}g/mL$) significantly inhibited PMA/Ionomycin-induced production of IL-5 and IL-13 and the expression of IL-4, IL-5, IL-6 and IL-13 mRNA in MC/9 mast cells. Moreover, MRAL (50 ${\mu}g/mL$, 100 ${\mu}g/mL$) inhibited PMA/Ionomycin-induced GATA-1, GATA-2, NFAT-1, NFAT-2, c-Fos protein expression and NF-${\kappa}B$ p65 DNA binding activity in MC/9 mast cells. Conclusions : In conclusion, we suspect the anti-allergenic activities of MRAL, may be related to the regulation of transcription factors GATA-1, GATA-2, NFAT-1, NFAT-2, c-Fos and NF-${\kappa}B$ p65 DNA binding assay causing inhibition of Th2 cytokines IL-5 and IL-13 in mast cells.

Induction of Apoptosis by Realgar on Lung Cancer Cells(A549), Stomach Center Cells(KATO) and Neuroglioma Cells(SNU-1118, U-87MG, U-373MG) (시험관내 폐암(肺癌), 위암(胃癌) 및 신경교종(神經膠腫) 세포(細胞)에 대한 석웅황(石雄黃)의 항암효과(抗癌效果))

  • Bang, Dae-Geon;Kim, Jin-Sung;Ryu, Bong-Ha
    • The Journal of Internal Korean Medicine
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    • v.28 no.2
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    • pp.294-303
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    • 2007
  • Objectives : We are aimed to identify anti-tumor effects of realgar on some kinds of cancer cells through molecular biologic methods. Materials & Methods : We used 5 kinds of cancer cell lines: lung cancer cells(A549). stomach cancer cells(KATO) and neuroglioma cells(SUN-1118. U-87MG, U-373MG). We injected the boiled extracts of realgar $50{\mu}g$. $100{\mu}g$ to cultural media( ml )for 24 hours. We measured the killing effects on 5 kinds of cancer cells through inverted and fluorescence microscope, the suppressive effects on viability of those cells via XTT assay and the effects on the revelation of Bax and Bcl-2 proteins related to apoptosis by western blotting. Results : In the changes of morphology, the extracts of realgar showed more significant killing effects on all cancer cells. especially KATO, SNU-1118, U-87MG, U-373MG, than the control group with dose dependence, which was statistically significant. In XTT assay, the extracts of realgar showed more suppressive effects on viability of all cancer cells, especially KATO and U-373MG, than the control group with dose dependence, which was statistically significant. In the revelation of proteins related to apoptosis, the extracts of realgar increased the level of Bax and decreased that of Bcl-2 in all cancer cells with dose dependence. Conclusions : We identified that realgar had more anti-tumor effects on stomach cancer and neuroglioma than on lung cancer in the experiments above. However, these basic experiments were performed in vitro. We hope the anti-tumor effects of realgar will be practically identified through more progressive research.

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Immunologic Mechanism of Experimental and Therapeutic Ultraviolet B Responses

  • Lew, Wook
    • IMMUNE NETWORK
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    • v.2 no.2
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    • pp.65-71
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    • 2002
  • The immunological mechanism of the responses to ultraviolet (UV) B radiation in mouse models were investigated by the suppression of contact hypersensitivity (CHS) and delayed type hypersensitivity (DTH), and susceptibility to infection. However, there are some differences in immune suppression according to the different models as well as the irradiation protocols. Therefore, this review focused on the differences in the suppressive effects on CHS and DTH, and susceptibility to infection in relation to the different in vivo models. Recent advances in cytokine knockout mice experiments have the reexamination of the role of the critical cytokines in UVB-induced immune suppression, which was investigated previously by blocking antibodies. The characteristics of the suppressor cells responsible for UVB-induced tolerance were determined. The subcellular mechanism of UVB-induced immune suppression was also explained by the induction of apoptotic cells through the Fas and Fas-ligand interaction. The phagocytosis of the apoptotic cells is believed to induce the production of the immune suppressive cytokine like interleukin-10 by macrophages. Therefore, the therapeutic UVB response to a skin disease, such as psoriasis, by the depletion of infiltrating T cells could be considered in the extension line of apoptosis and immune suppression.

Suppressive Effect of Acanthopanax sessiliflorus Extract on the DNA and Cell Damage by Dieldrin (Dieldrin에 의한 DNA와 세포 손상에 대한 오가피 추출물의 억제효과)

  • Ryu, A-Reum;Kim, Ji-Hae;Lee, Mi-Young
    • Korean Journal of Medicinal Crop Science
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    • v.20 no.4
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    • pp.245-250
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    • 2012
  • Dieldrin, one of the organochlorine pesticides (OCPs), induced the damages in neuroblastoma cells and DNA damages in lymphocytes. The ethanol extracts of A. sessiliflorus leaves were examined for the suppressive effects on the dieldrin-induced cell damages. Moreover, the extract was used to test whether it might inhibit the oxidative DNA damage of lymphocytes using Comet assay. The cell and DNA damage by dieldrin were suppressed in vitro upon treating A. sessiliflorus extract. This result suggests that A. sessiliflorus extract might be useful to reduce dieldrin toxicity.

Antioxidant and immuno-enhancing effects of Echinacea purpurea (American herb) in vivo

  • Gu, Yeun-Hwa;Maenaka, Toshihiro;Saito, Kiyoto;Yamashita, Takenori;Choi, In-Suk;Terai, Kaoru;Ahn, Kyoo-Seok
    • Advances in Traditional Medicine
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    • v.5 no.1
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    • pp.48-56
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    • 2005
  • We studied the protective effect of Echinacea purpurea against radiation by evaluating changes in the peripheral blood cell count and peripheral blood antioxidant activity. Echinacea purpurea administration had a suppressive effect on radiation-induced leukopenia, especially on lymphocytes and monocytes and resulted in a faster recovery of blood cell counts. Mouse peripheral blood antioxidant activity was increased by Echinacea purpurea, and a relationship between the suppressive effect on radiation-induced leukopenia and the antioxidant effect was suggested.

Health Promoting Effects of Lactoferrin from Milk

  • Shimizu, Hirohiko;Ando, Kunio;Hoshino, Tatsuo
    • Journal of Dairy Science and Biotechnology
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    • v.24 no.2
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    • pp.21-24
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    • 2006
  • The ubiquitous presence of lactoferrin(LF) receptor in human as reported by the research group of Prof. Bo Lonnerdal, Univ. California (Suzuki, Y. A.,2001) encouraged us to search for the unknown physiological roles of Lf. Under the collaboration with Prof. Etsumori Harada, Tottori Univ., and his research group, we have found two novel biological activities of LF as the control of the lipid metabolism and the effect on the central nervous system. Relating to the lipid metabolism, LF could, in animal experiments, reduce triglyceride and total cholesterol both in blood and liver (Takeuchi, T et αl., 2003). LF increased plasms HDL-C and lowered LDL-C. In the central nervous system, LF showed anti-nociceptive activity mediated by ${\mu}$-opioid receptor in the rat spinal cord (Hayashida, K. et al., 2003). LF enhanced analgesic action of morphine synergistically via nitric oxide synthesis (Hayashida, K., et al., 2003) LF showed opioid-mediated suppressive effect on distress induced by maternal separation in rat pups (Takeuchi, T., et al., 2003).

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