28 research outputs found

    Trypanosoma cruzi Infection Induces Cellular Stress Response and Senescence-Like Phenotype in Murine Fibroblasts

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    Trypanosoma cruzi infects and replicates within a wide variety of immune and non-immune cells. Here, we investigated early cellular responses induced in NIH-3T3 fibroblasts upon infection with trypomastigote forms of T. cruzi. We show that fibroblasts were susceptible to T. cruzi infection and started to release trypomastigotes to the culture medium after 4 days of infection. Also, we found that T. cruzi infection reduced the number of fibroblasts in 3-day cell cultures, by altering fibroblast proliferation. Infected fibroblasts displayed distinctive phenotypic alterations, including enlarged and flattened morphology with a nuclei accumulation of senescence-associated heterochromatin foci. In addition, infection induced an overexpression of the enzyme senescence-associated β-galactosidase (SA-β-gal), an activation marker of the cellular senescence program, as well as the production of cytokines and chemokines involved with the senescence-associated secretory phenotype (SASP) such as IL-6, TNF-α, IL-1β, and MCP-1. Infected fibroblasts released increased amounts of stress-associated factors nitric oxide (NO) and reactive oxygen species (ROS), and the treatment with antioxidants deferoxamine (DFO) and N-acetylcysteine reduced ROS generation, secretion of SASP-related cytokine IL-6, SA-β-gal activity, and parasite load by infected fibroblasts. Taken together, our data suggest that T. cruzi infection triggers a rapid cellular stress response followed by induction of a senescent-like phenotype in NIH-3T3 fibroblasts, enabling them to act as reservoirs of parasites during the early stages of the Chagas disease

    All-Trans Retinoic Acid Promotes an M1- to M2-Phenotype Shift and Inhibits Macrophage-Mediated Immunity to Leishmania major

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    As key cells, able to host and kill Leishmania parasites, inflammatory monocytes/macrophages are potential vaccine and therapeutic targets to improve immune responses in Leishmaniasis. Macrophage phenotypes range from M1, which express NO-mediated microbial killing, to M2 macrophages that might help infection. Resistance to Leishmaniasis depends on Leishmania species, mouse strain, and both innate and adaptive immunity. C57BL/6 (B6) mice are resistant and control infection, whereas Leishmania parasites thrive in BALB/c mice, which are susceptible to develop cutaneous lesions in the course of infection with Leishmania major, but not upon infection with Leishmania braziliensis. Here, we investigated whether a deficit in early maturation of inflammatory monocytes into macrophages in BALB/c mice underlies increased susceptibility to L. major versus L. braziliensis parasites. We show that, after infection with L. braziliensis, monocytes are recruited to peritoneum, differentiate into macrophages, and develop an M1 phenotype able to produce proinflammatory cytokines in both B6 and BALB/c mice. Nonetheless, more mature macrophages from B6 mice expressed inducible NO synthase (iNOS) and higher NO production in response to L. braziliensis parasites, whereas BALB/c mice developed macrophages expressing an incomplete M1 phenotype. By contrast, monocytes recruited upon L. major infection gave rise to immature macrophages that failed to induce an M1 response in BALB/c mice. Overall, these results are consistent with the idea that resistance to Leishmania infection correlates with improved maturation of macrophages in a mouse-strain and Leishmania-species dependent manner. All-trans retinoic acid (ATRA) has been proposed as a therapy to differentiate immature myeloid cells into macrophages and help immunity to tumors. To prompt monocyte to macrophage maturation upon L. major infection, we treated B6 and BALB/c mice with ATRA. Unexpectedly, treatment with ATRA reduced proinflammatory cytokines, iNOS expression, and parasite killing by macrophages. Moreover, ATRA promoted an M1 to M2 transition in bone marrow-derived macrophages from both strains. Therefore, ATRA uncouples macrophage maturation and development of M1 phenotype and downmodulates macrophage-mediated immunity to L. major parasites. Cautions should be taken for the therapeutic use of ATRA, by considering direct effects on innate immunity to intracellular pathogens

    All-Trans Retinoic Acid Promotes an M1- to M2-Phenotype Shift and Inhibits Macrophage-Mediated Immunity to Leishmania major

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    Submitted by Sandra Infurna ([email protected]) on 2018-02-08T13:54:27Z No. of bitstreams: 1 flavia_gomes_etal_IOC_2017.pdf: 2075160 bytes, checksum: c2d3310b10a694168677721b82bc5c17 (MD5)Approved for entry into archive by Sandra Infurna ([email protected]) on 2018-02-08T14:06:59Z (GMT) No. of bitstreams: 1 flavia_gomes_etal_IOC_2017.pdf: 2075160 bytes, checksum: c2d3310b10a694168677721b82bc5c17 (MD5)Made available in DSpace on 2018-02-08T14:06:59Z (GMT). No. of bitstreams: 1 flavia_gomes_etal_IOC_2017.pdf: 2075160 bytes, checksum: c2d3310b10a694168677721b82bc5c17 (MD5) Previous issue date: 2017Universidade Federal do Rio de Janeiro. Instituto de BiofĂ­sica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil.Universidade Federal do Rio de Janeiro. Instituto de BiofĂ­sica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil.Universidade Federal do Rio de Janeiro. Instituto de BiofĂ­sica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil.Universidade Federal do Rio de Janeiro. Instituto de BiofĂ­sica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil / Universidade Federal do Rio de Janeiro. Instituto de Microbiologia Paulo de GĂłes. Rio de Janeiro, RJ, Brasil.Universidade Federal do Rio de Janeiro. Instituto de BiofĂ­sica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil / Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ, Brasil.Universidade Federal do Rio de Janeiro. Instituto de BiofĂ­sica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil.Universidade Federal do Rio de Janeiro. Instituto de BiofĂ­sica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil / Conselho Nacional de Desenvolvimento CientĂ­fico e TecnolĂłgico. Instituto Nacional para Pesquisa Translacional em SaĂşde e Ambiente na RegiĂŁo AmazĂ´nica. Rio de Janeiro, RJ, Bbrasil.Universidade Federal do Rio de Janeiro. Instituto de BiofĂ­sica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil.As key cells, able to host and kill Leishmania parasites, inflammatory monocytes/macrophages are potential vaccine and therapeutic targets to improve immune responses in Leishmaniasis. Macrophage phenotypes range from M1, which express NO-mediated microbial killing, to M2 macrophages that might help infection. Resistance to Leishmaniasis depends on Leishmania species, mouse strain, and both innate and adaptive immunity. C57BL/6 (B6) mice are resistant and control infection, whereas Leishmania parasites thrive in BALB/c mice, which are susceptible to develop cutaneous lesions in the course of infection with Leishmania major, but not upon infection with Leishmania braziliensis. Here, we investigated whether a deficit in early maturation of inflammatory monocytes into macrophages in BALB/c mice underlies increased susceptibility to L. major versus L. braziliensis parasites. We show that, after infection with L. braziliensis, monocytes are recruited to peritoneum, differentiate into macrophages, and develop an M1 phenotype able to produce proinflammatory cytokines in both B6 and BALB/c mice. Nonetheless, more mature macrophages from B6 mice expressed inducible NO synthase (iNOS) and higher NO production in response to L. braziliensis parasites, whereas BALB/c mice developed macrophages expressing an incomplete M1 phenotype. By contrast, monocytes recruited upon L. major infection gave rise to immature macrophages that failed to induce an M1 response in BALB/c mice. Overall, these results are consistent with the idea that resistance to Leishmania infection correlates with improved maturation of macrophages in a mouse-strain and Leishmania-species dependent manner. All-trans retinoic acid (ATRA) has been proposed as a therapy to differentiate immature myeloid cells into macrophages and help immunity to tumors. To prompt monocyte to macrophage maturation upon L. major infection, we treated B6 and BALB/c mice with ATRA. Unexpectedly, treatment with ATRA reduced proinflammatory cytokines, iNOS expression, and parasite killing by macrophages. Moreover, ATRA promoted an M1 to M2 transition in bone marrow-derived macrophages from both strains. Therefore, ATRA uncouples macrophage maturation and development of M1 phenotype and downmodulates macrophage-mediated immunity to L. major parasites. Cautions should be taken for the therapeutic use of ATRA, by considering direct effects on innate immunity to intracellular pathogens

    Trypanosoma cruzi Infection Induces Cellular Stress Response and Senescence-Like Phenotype in Murine Fibroblasts

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    Submitted by Sandra Infurna ([email protected]) on 2019-02-05T14:21:19Z No. of bitstreams: 1 alexandre2_morrot_etal_IOC_2018.pdf: 2547165 bytes, checksum: 3c339420d50f9918dcac548b2244b769 (MD5)Approved for entry into archive by Sandra Infurna ([email protected]) on 2019-02-05T14:36:28Z (GMT) No. of bitstreams: 1 alexandre2_morrot_etal_IOC_2018.pdf: 2547165 bytes, checksum: 3c339420d50f9918dcac548b2244b769 (MD5)Made available in DSpace on 2019-02-05T14:36:28Z (GMT). No. of bitstreams: 1 alexandre2_morrot_etal_IOC_2018.pdf: 2547165 bytes, checksum: 3c339420d50f9918dcac548b2244b769 (MD5) Previous issue date: 2018Universidade Federal do Rio de Janeiro. Instituto de BiofĂ­sica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil / Universidade Federal do Rio de Janeiro. Instituto de Microbiologia Paulo de GĂłes. Departamento de Imunologia. Rio de Janeiro, RJ, Brasil.Universidade Federal do Rio de Janeiro. Instituto de BiofĂ­sica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil.Universidade Federal do Rio de Janeiro. Instituto de BiofĂ­sica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil / Universidade Federal do Rio de Janeiro. Instituto de Microbiologia Paulo de GĂłes. Departamento de Imunologia. Rio de Janeiro, RJ, Brasil.Universidade Federal do Rio de Janeiro. Faculdade de Medicina. Rio de Janeiro, RJ, Brasil / Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. LaboratĂłrio de Imunoparasitologia. Rio de Janeiro, RJ, Brasil.Universidade Federal do Rio de Janeiro. Instituto de BiofĂ­sica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil.Universidade Federal do Rio de Janeiro. Instituto de BiofĂ­sica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil.Universidade Federal do Rio de Janeiro. Instituto de BiofĂ­sica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil / Instituto Nacional para Pesquisa Translacional em SaĂşde e Ambiente na RegiĂŁo AmazĂ´nica. Conselho Nacional de Desenvolvimento CientĂ­fico e TecnolĂłgico. Rio de Janeiro, RJ, Brasil.Universidade Federal do Rio de Janeiro. Instituto de BiofĂ­sica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil / Universidade Federal do Rio de Janeiro. Instituto de Microbiologia Paulo de GĂłes. Departamento de Imunologia. Rio de Janeiro, RJ, Brasil.Trypanosoma cruzi infects and replicates within a wide variety of immune and non-immune cells. Here, we investigated early cellular responses induced in NIH-3T3 fibroblasts upon infection with trypomastigote forms of T. cruzi. We show that fibroblasts were susceptible to T. cruzi infection and started to release trypomastigotes to the culture medium after 4 days of infection. Also, we found that T. cruzi infection reduced the number of fibroblasts in 3-day cell cultures, by altering fibroblast proliferation. Infected fibroblasts displayed distinctive phenotypic alterations, including enlarged and flattened morphology with a nuclei accumulation of senescence-associated heterochromatin foci. In addition, infection induced an overexpression of the enzyme senescence-associated β-galactosidase (SA-β-gal), an activation marker of the cellular senescence program, as well as the production of cytokines and chemokines involved with the senescence-associated secretory phenotype (SASP) such as IL-6, TNF-α, IL-1β, and MCP-1. Infected fibroblasts released increased amounts of stress-associated factors nitric oxide (NO) and reactive oxygen species (ROS), and the treatment with antioxidants deferoxamine (DFO) and N-acetylcysteine reduced ROS generation, secretion of SASP-related cytokine IL-6, SA-β-gal activity, and parasite load by infected fibroblasts. Taken together, our data suggest that T. cruzi infection triggers a rapid cellular stress response followed by induction of a senescent-like phenotype in NIH-3T3 fibroblasts, enabling them to act as reservoirs of parasites during the early stages of the Chagas disease

    Cellular Stress and Senescence Induction during <i>Trypanosoma cruzi</i> Infection

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    Chagas disease (CD) is a neglected tropical disease caused by Trypanosoma cruzi infection that, despite being discovered over a century ago, remains a public health problem, mainly in developing countries. Since T. cruzi can infect a wide range of mammalian host cells, parasite–host interactions may be critical to infection outcome. The intense immune stimulation that helps the control of the parasite’s replication and dissemination may also be linked with the pathogenesis and symptomatology worsening. Here, we discuss the findings that support the notion that excessive immune system stimulation driven by parasite persistence might elicit a progressive loss and collapse of immune functions. In this context, cellular stress and inflammatory responses elicited by T. cruzi induce fibroblast and other immune cell senescence phenotypes that may compromise the host’s capacity to control the magnitude of T. cruzi-induced inflammation, contributing to parasite persistence and CD progression. A better understanding of the steps involved in the induction of this chronic inflammatory status, which disables host defense capacity, providing an extra advantage to the parasite and predisposing infected hosts prematurely to immunosenescence, may provide insights to designing and developing novel therapeutic approaches to prevent and treat Chagas disease

    Axl receptor induces efferocytosis, dampens M1 macrophage responses and promotes heart pathology in Trypanosoma cruzi infection

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    The tyrosine kinase receptor Axl induces efferocytosis, disrupts M1 responses, and promotes parasite infection and heart pathology in experimental Chagas disease

    Infection with Leishmania major Induces a Cellular Stress Response in Macrophages

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    Made available in DSpace on 2015-05-27T13:39:43Z (GMT). No. of bitstreams: 2 license.txt: 1914 bytes, checksum: 7d48279ffeed55da8dfe2f8e81f3b81f (MD5) marise_nunesetal_IOC_2014.pdf: 991260 bytes, checksum: 9a761dfc21ca56fafd41c0c53b2b8169 (MD5) Previous issue date: 2014Universidade Federal do Rio de Janeiro. Instituto de Biofísica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil.Universidade Federal do Rio de Janeiro. Instituto de Biofísica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil.Universidade Federal do Rio de Janeiro. Instituto de Biofísica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil.Universidade Federal do Rio de Janeiro. Instituto de Biofísica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil.National Institute of Health. Laboratory of Parasitic Diseases. Bethesda, MA, USA.Universidade Federal do Rio de Janeiro. Instituto de Biofísica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil.Universidade Federal do Rio de Janeiro. Instituto de Biofísica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil.Universidade Federal do Rio de Janeiro. Instituto de Biofísica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ, Brasil.Universidade Federal do Rio de Janeiro. Instituto de Biofísica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil.We investigated early cellular responses induced by infection with Leishmania major in macrophages from resistant C57/BL6 mice. Infection increased production of reactive oxygen species by resident, but not inflammatory peritoneal macrophages. In addition, infection increased activation of stress-activated protein kinases/c-Jun N-terminal kinases (SAPK/JNK) in resident, but not in inflammatory peritoneal macrophages. Infection also increased expression of membrane and soluble FasL, but infected macrophages remained viable after 48 h. Infection increased secretion of cytokines/chemokines TNF-α, IL-6, TIMP-1, IL-1RA, G-CSF, TREM, KC, MIP-1α, MIP-1β, MCP-1, and MIP-2 in resident macrophages. Addition of antioxidants deferoxamine and N-acetylcysteine reduced ROS generation and JNK activation. Addition of antioxidants or JNK inhibitor SP600125 reduced secretion of KC. Furthermore, treatment with antioxidants or JNK inhibitor also reduced intracellular parasite replication. These results indicated that infection triggers a rapid cellular stress response in resident macrophages which induces proinflammatory signals, but is also involved in parasite survival and replication in host macrophages

    Influence of composition and continuous casting parameters on the cracking of b-microalloyed high Mn steel grades

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    B-1 cells can be differentiated from B-2 cells because they are predominantly located in the peritoneal and pleural cavities and have distinct phenotypic patterns and activation properties. A mononuclear phagocyte derived from B-1 cells (B-1CDP) has been described. As the B-1CDP cells migrate to inflammatory/infectious sites and exhibit phagocytic capacity, the microbicidal ability of these cells was investigated using the Leishmania major infection model in vitro. The data obtained in this study demonstrate that B-1CDP cells are more susceptible to infection than peritoneal macrophages, since B-1CDP cells have a higher number of intracellular amastigotes forms and consequently release a larger number of promastigotes. Exacerbated infection by L. major required lipid bodies/PGE2 and IL-10 by B-1CDP cells. Both infection and the production of IL-10 were decreased when PGE2 production was blocked by NSAIDs. The involvement of IL-10 in this mechanism was confirmed, since B-1CDP cells from IL-10 KO mice are more competent to control L. major infection than cells from wild type mice. These findings further characterize the B-1CDP cells as an important mononuclear phagocyte that plays a previously unrecognized role in host responses to L. major infection, most likely via PGE2-driven production of IL-10

    Effect of JNK inhibitor on release of KC, JNK activity and intramacrophagic parasite growth.

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    <p>(A) Resident macrophages were infected or not with <i>L. major</i> in the presence of solvent or the indicated MAPK inhibitors. The levels of KC were determined by ELISA after 20 h of infection. (B) Macrophages were infected or not in the presence of solvent or JNK inhibitor SP600125. After 4 h, the levels of JNK and p-JNK were determined by western blotting. (C) Macrophages were infected overnight and cultured for additional 3 d in the presence of solvent or MAPK inhibitors. Intracellular load of parasites was evaluated. Results are mean and SE of the number of extracellular promastigotes produced. *<i>P</i><0.05, compared to treatment with solvent.</p
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