• Title/Summary/Keyword: mitogenic activity

Search Result 99, Processing Time 0.027 seconds

Newly Identified TLR9 Stimulant, M6-395 Is a Potent Polyclonal Activator for Murine B Cells

  • Park, Mi-Hee;Jung, Yu-Jin;Kim, Pyeung-Hyeun
    • IMMUNE NETWORK
    • /
    • v.12 no.1
    • /
    • pp.27-32
    • /
    • 2012
  • Background: Toll-like receptors (TLRs) have been extensively studied in recent years. However, functions of these molecules in murine B cell biology are largely unknown. A TLR4 stimulant, LPS is well known as a powerful polyclonal activator for murine B cells. Methods: In this study, we explored the effect of a murine TLR9 stimulant, M6-395 (a synthetic CpG ODNs) on B cell proliferation and Ig production. Results: First, M6-395 was much more potent than LPS in augmenting B cell proliferation. As for Ig expression, M6-395 facilitated the expression of both TGF-${\beta}1$-induced germ line transcript ${\alpha}$ ($GLT{\alpha}$) and IL-4-induced $GLT{\gamma}1$ as levels as those by LPS and Pam3CSK4 (TLR1/2 agonist) : a certain Ig GLT expression is regarded as an indicative of the corresponding isotype switching recombination. However, IgA and IgG1 secretion patterns were quite different--these Ig isotype secretions by M6-395 were much less than those by LPS and Pam3CSK4. Moreover, the increase of IgA and IgG1 production by LPS and Pam3CSK4 was virtually abrogated by M6-395. The same was true for the secretion of IgG3. We found that this unexpected phenomena provoked by M6-395 is attributed, at least in part, to its excessive mitogenic nature. Conclusion: Taken together, these results suggest that M6-395 can act as a murine polyclonal activator but its strong mitogenic activity is unfavorable to Ig isotype switching.

Effects of Dangguijakyak-san Extract on Nitric Oxide Production and Cytokine Gene Expression in RAW 264.7 Macrophages Cell (당귀작약산이 마우스 대식세포주의 NO 생성 및 사이토카인 유전자 발현에 미치는 영향)

  • Shin Sang Woo;Lee Young Sun;Park Jong Hyun;Kwon Taeg Kyu;Suh Seong Il;Kwon Young Kyu
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.18 no.5
    • /
    • pp.1443-1448
    • /
    • 2004
  • The present study was conducted to evaluate the immunomodulatory effects of Dangguijakyak-san(당귀작약산). We investigated the effects of cell proliferation in mouse spleen cell and RAW 264.7 macrophages cells. Dangguijakyak-san enhanced mitogenic activity in the dose-response manner in mouse spleen cells and RAW 264.7 macrophages cells. In nitric oxide (NO) synthesis and iNOS mRNA expression by Dangguijakyak-san, Dangguijakyaksan alone had an effect on NO synthesis and iNOS mRNA expression in RAW 264.7 cells. NO production and iNOS mRNA expression which is excessively induced by LPS decreased after treatment of Dangguijakyak-san. The expressions of cytokine gene by Dangguijakyak-san investigated using reverse transcription polymerase chain reaction (RT-PCR). In RT-PCR, IL-1α, IL-1β and IL-6 mRNA expressions induced in Dangguijakyak-san-treated RAW 264.7 cells. These data indicate that 1) Dangguijakyak-san can modulate various immune response and 2) the immunomodulatory effects of Dangguijakyak-san may be, in part, associated with the regulation of NO synthesis, the expressions of these cytokine as well as the mitogenic effect on spleen cells and macrophages cells.

Immunomodulatory Effects of Aqueous-extracted Zingiberis rhizoma on Methorexate Induced Immune Suppression in Mouse Spleen Cell (건강 열수추출액이 Methotrexate에 의해 유도된 마우스 면역억제 조절에 미치는 영향)

  • Lee, Young-Sun;Lee, Geum-Hong;Kim, Sang-Chan;Kwon, Young-Kyu;Shin, Sang-Woo
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.20 no.4
    • /
    • pp.896-901
    • /
    • 2006
  • Zingiberis rhizoma(ZB) has been used to treat a various condition and disease in traditional oriental medicine. The present study was conducted to evaluate the immunomodulatory effect of aqueous-extracted ZB(ZBE) on methotrexate (MTX)-induced immune suppression in mouse spleen cells. In spleen cell proliferation assay, ZBE enhanced mitogenic activity in mouse spleen cells. In RT-PCR, ZBE induced IL-2, IFNr and IL-6 cytokine gene expression in mouse spleen cells. In spite of MTX treatment, IL-2, IFNr and IL-6 gene expressions sustained in MTX treated spleen cells. CD45R/B220, pan B marker was slightly increased in ZBE treated mouse spleen cells. IL-6, B cell tropical cytokine, production was induced by ZBE-treated mouse spleen cells and IL-6 production was sustained on MTX-ZBE co-cultured cells. ZBE administration enhanced suNival of S-180 bearing mouse. These data indicate that ZBE has a protective effect of immune suppression caused by MTX, and ZBE may be enhance cellular and humoral function by regulate cytokine gene expression as well as the mitogenic effect on spleen cells.

Merlin, a regulator of Hippo signaling, regulates Wnt/β-catenin signaling

  • Kim, Soyoung;Jho, Eek-hoon
    • BMB Reports
    • /
    • v.49 no.7
    • /
    • pp.357-358
    • /
    • 2016
  • Merlin, encoded by the NF2 gene, is a tumor suppressor that exerts its function via inhibiting mitogenic receptors at the plasma membrane. Although multiple mutations in Merlin have been identified in Neurofibromatosis type II (NF2) disease, its molecular mechanism is not fully understood. Here, we show that Merlin interacts with LRP6 and inhibits LRP6 phosphorylation, a critical step for the initiation of Wnt signaling. We found that treatment of Wnt3a caused phosphorylation of Merlin by PAK1, leading to detachment of Merlin from LRP6 and allowing the initiation of Wnt/β-catenin signaling. A higher level of β-catenin was found in tissues from NF2 patients. Enhanced proliferation and migration caused by knockdown of Merlin in glioblastoma cells were inhibited by suppression of β-catenin. Conclusively, these results suggest that sustained Wnt/β-catenin signaling activity induced by abrogation of Merlin-mediated inhibition of LRP6 phosphorylation might be a cause of NF2 disease.

Factors Influencing Satellite Cell Activity during Skeletal Muscle Development in Avian and Mammalian Species

  • Nierobisz, Lidia S;Mozdziak, Paul E
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.21 no.3
    • /
    • pp.456-464
    • /
    • 2008
  • Avian and mammalian skeletal muscles exhibit a remarkable ability to adjust to physiological stressors induced by growth, exercise, injury and disease. The process of muscle recovery following injury and myonuclear accretion during growth is attributed to a small population of satellite cells located beneath the basal lamina of the myofiber. Several metabolic factors contribute to the activation of satellite cells in response to stress mediated by illness, injury or aging. This review will describe the regenerative properties of satellite cells, the processes of satellite cell activation and highlight the potential role of satellite cells in skeletal muscle growth, tissue engineering and meat production.

Studies on Lectins from Mushrooms(II) - Screening of Bioactive Substance, Lectins, from Korean Wild Mushrooms. (버섯류의 렉틴 성분 개발연구 (II) - 야생 버섯류의 생리활성 물질, 렉틴 성분 검색)

  • 전경희;김무경;정시련
    • YAKHAK HOEJI
    • /
    • v.31 no.4
    • /
    • pp.213-218
    • /
    • 1987
  • Twenty species of higher fungi growing in the wild were collected and studied extensively for their lectin activities by using erythrocytes of human, rabbit and mouse blood. In total, 14 species demonstrated hemagglutination with some kinds of erythrocytes. Of twenty species, eight (Boletus edulis, B. splendidus, Clavaria zollingeri, Lactaritis subzonarius, L. volemus, Russula cutefracta, Pholiota squarrosa, and P. aspera) were shown lymphoagglutination with murine splenic lymphocytes. Protein contents were estimated from the crude lectin fraction. Above mentioned eight species contained relatively high amounts of proteins than other mushrooms. Since these species had coincidently, hiig emagglutinating activity as well, we could define them as lectin-containeing mushrooms. Some species also contained mitogenic lectins toward murine splenic lymphocytes.

  • PDF

Inhibitory Effect of Scutellaria barbata Don Water-extracts on Growth and DNA Incorporation of Human Cancer Cells

  • Kim, Dong-Il
    • The Journal of Korean Medicine
    • /
    • v.27 no.4
    • /
    • pp.162-173
    • /
    • 2006
  • The water-extracts of Scutellaria barbata Don (SBDE) were isolated from Chinese medicinal plant sources. The extracts showed strong growth-inhibitory activity and cancer chemopreventive activity on the growth and DNA incorporation of MG63 human osteosarcoma and K562 human leukemia cell lines. The growth of human cancer cells was inhibited in the presence of the extracts (20, 50 and 100 ${\mu}$g/ml), and the effects were concentration-dependent and incubation time-dependent up to 8 days. When 50 ${\mu}$g/ml of the extracts was added to the media of MG63 and K562, cell growth after 8 days or 6 days of incubation was retarded by 93.2 to 97.3% of the control group. Morphological changes of MG63 and K562 cell lines were observed. As the concentration of the extracts increased up to 50 ${\mu}$g/ml, degree of cell aggregation decreased. Moreover, the DNA incorporation of the cells which were labeled with [3H] thymidine was significantly reduced after 3 days of incubation at $37^{\circ}C$ with the extract. Therefore, it is suggested that the extract is highly effective on inhibition of cancer cell growth. The extract also inhibited gene expression of IGF-II in transcriptional level. Since IGF-II works as a mitogenic effector on MG63 and K562 cell lines, these results suggest that the growth inhibition is in part mediated through the inhibition of IGF-II gene expression.

  • PDF

In Vitro Studies on Phytochemical Content, Antioxidant, Anticancer, Immunomodulatory, and Antigenotoxic Activities of Lemon, Grapefruit, and Mandarin Citrus Peels

  • Diab, Kawthar AE
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.17 no.7
    • /
    • pp.3559-3567
    • /
    • 2016
  • Background: In recent years, there has been considerable research on recycling of agro-industrial waste for production of bioactive compounds. The food processing industry produces large amounts of citrus peels that may be an inexpensive source of useful agents. Objective: The present work aimed to explore the phytochemical content, antioxidant, anticancer, antiproliferation, and antigenotxic activities of lemon, grapefruit, and mandarin peels. Materials and Methods: Peels were extracted using 98% ethanol and the three crude extracts were assessed for their total polyphenol content (TPC), total flavonoid content (TFC), and antioxidant activity using DPPH (1, 1-diphenyl-2-picrylhydrazyl). Their cytotoxic and mitogenic proliferation activities were also studied in human leukemia HL-60 cells and mouse splenocytes by CCK-8 assay. In addition, genotoxic/antigenotoxic activity was explored in mouse splenocytes using chromosomal aberrations (CAs) assay. Results: Lemon peels had the highest of TPC followed by grapefruit and mandarin. In contrast, mandarin peels contained the highest of TFC followed by lemon and grapefruit peels. Among the extracts, lemon peel possessed the strongest antioxidant activity as indicated by the highest DPPH radical scavenging, the lowest effective concentration 50% ($EC_{50}=42.97{\mu}g\;extract/mL$), and the highest Trolox equivalent antioxidant capacity (TEAC=0.157). Mandarin peel exhibited moderate cytotoxic activity ($IC_{50}=77.8{\mu}g/mL$) against HL-60 cells, whereas grapefruit and lemon peels were ineffective anti-leukemia. Further, citrus peels possessed immunostimulation activity via augmentation of proliferation of mouse splenocytes (T-lymphocytes). Citrus extracts exerted non-cytotoxic, and antigenotoxic activities through remarkable reduction of CAs induced by cisplatin in mouse splenocytes for 24 h. Conclusions: The phytochemical constituents of the citrus peels may exert biological activities including anticancer, immunostimulation and antigenotoxic potential.

Cancer Chemoprevention by Tea Polyphenols Through Modulating Signal Transduction Pathways

  • Lin, Jen-Kun
    • Archives of Pharmacal Research
    • /
    • v.25 no.5
    • /
    • pp.561-571
    • /
    • 2002
  • The action mechanisms of several chemopreventive agents derived from herbal medicine and edible plants have become attractive issues in cancer research. Tea is the most widely consumed beverage worldwide. Recently, the cancer chemopreventive actions of tea have been intensively investigated. It have been demonstrated that the active principles of tea were attributed to their tea polyphenols. Recently, tremendous progress has been made in elucidating the molecular mechanisms of cancer chemoprevention by tea and tea polyphenols. The suppression of various tumor biomarkers including growth factor receptor tyrosine kinases, cytokine receptor kinases, P13K, phosphatases, ras, raf, MAPK cascades, NㆍFB, IㆍB kinase, PKA, PKB, PKC, c-jun, c-fos, c-myc, cdks, cyclins, and related transducing proteins by tea polyphenols has been studied in our laboratory and others. The IㆍB kinase (IKK) activity in LPS-activated murine macrophages (RAW 264.7 cells) was found to be inhibited by various tea polyphenols including (-) epigallocatechin-3-gallate (EGCG), theaflavin (TF-1), theaflavin-3-gal-late (TF-2) and theaflavin-3,3'-digallate (TF-3). TF-3 inhibited IKK activity in activated macrophages more strongly than did the other tea polyphenols. TF-3 inhibited both IKK1 and IKK2 activity and prevented the degradation of IㆍBㆍand IㆍBㆍin activated macrophage cells. The results suggested that the inhibition of IKK activity by TF-3 and other tea polyphenols could occur by a direct effect on IKKs or on upstream events in the signal transduction pathway. TF-3 and other tea polyphenols blocked phosphorylation of IB from the cytosolic fraction, inhibited NFB activity and inhibited increases in inducible nitric oxide synthase levels in activated macrophage. TF-3 and other tea polyphenols also inhibited strongly the activities of xanthine oxidase, cyclooxygenase, EGF-receptor tyrosine kinase and protein kinase C. These results suggest that TF-3 and other tea polyphenols may exert their cancer chemoprevention through suppressing tumor promotion and inflammation by blocking signal transduction. The mechanisms of this inhibition may be due to the blockade of the mitogenic and differentiating signals through modulating EGFR function, MAPK cascades, NFkB activation as wll as c-myc, c-jun and c-fos expression.

THE EFFECT OF TRANSFORMING GROWTH $FACTOR-B_1$ ON THE PROLIFERATION RATE OF HUMAN PERIODONTAL LIGAMENT CELLS AND HUMAN GINGIVAL FIBROBLASTS. (변형성장인자-${\beta}_1$이 치주인대세포와 치은섬유아세포의 증식에 미치는 영향)

  • Cho, Eun-Kyeung;Lee, Jae-Mok;Suh, Jo-Young
    • Journal of Periodontal and Implant Science
    • /
    • v.25 no.3
    • /
    • pp.720-732
    • /
    • 1995
  • The use of transforming growth $factor-{\beta}1$ which functions as a potent biologic mediator regulating numerous activities of wound healing has been suggested for the promotion of periodontal regeneration. The mitogenic effects of transforming growth $factor-{\beta}1$ on human periodontal ligament cells and human gingival fibroblasts were evaluated by determining the incorporation of $[^3H]-thymidine$ into DNA of the cells dose-dependently. Cells were prepared with primary cultured fibroblasts and periodontal ligament cells from humans, and used in experiments were the fourth or sixth subpassage. Cells were seeded with serum free Dulbecco's modified Eagle medium containing 0.1% bovine serum albumine. The added concentrations of transforming growth $factor-{\beta}1$ were 0.25, 0.5, 1, 2.5, 5ng/ml and transforming growth $factor-{\beta}1$ were added to the quiescent cells for 24hours, 48hours, 72hours. They were labeled with lnCi/ml $[^3H]$ thymidine for the last 24hour of the each culture. The results were presented as the mean counts per minute (CPM) per well and S.D. of four determinations. The results were as follows. : The DNA synthetic activity of human gingival fibroblasts was increased dose-dependently by transforming growth $factor-{\beta}1$ at 24 hours, 48 hours and 72 hours. The maximum mitogenic effects were at the 48 hour application of transforming growth $factor-{\beta}1$. The DNA synthetic activity was generally more decreased at the 72 hour application than at the 48 hour the application of transforming growth $factor-{\beta}1$. The DNA synthetic activity of human periodontal ligament cells was increased dose-dependently by transforming growth $factor-{\beta}1$ at 24 hours and 48 hours. But the DNA synthetic activity was decreased at 5ng/ml of the 72 hour application. The maximum mitogenic effects were also at the 48 hour application of transforming growth $factor-{\beta}1$. The DNA synthetic activity of human periodontal ligament cells was generally more decreased at the 72 hour application than at the 48 hour application of transforming growth $factor-{\beta}1$. In the comparision of DNA synthetic activity between the human gingival fibroblasts and human periodontal ligament cells, the human gingival fibroblasts had more activity than the human periodontal ligament cells at all time application with the concentration of transforming growth $factor-{\beta}1$. In conclusion, transforming growth $factor-{\beta}1$ has an important roles in the stimulation of DNA synthesis in human periodontal ligament cells and human gingival fibroblasts, which means an increase in collagen synthesizing cells and thus, may be useful for clinical application in periodontal regenerative procedures.

  • PDF