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1.
Mol Neurobiol ; 60(2): 481-494, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36280654

RESUMO

Acute cerebral dysfunction is a pathological state common in severe infections and a pivotal determinant of long-term cognitive outcomes. Current evidence indicates that a loss of synaptic contacts orchestrated by microglial activation is central in sepsis-associated encephalopathy. However, the upstream signals that lead to microglial activation and the mechanism involved in microglial-mediated synapse dysfunction in sepsis are poorly understood. This study investigated the involvement of the NLRP3 inflammasome in microglial activation and synaptic loss related to sepsis. We demonstrated that septic insult using the cecal ligation and puncture (CLP) model induced the expression of NLRP3 inflammasome components in the brain, such as NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3), apoptosis-associated speck-like protein containing a C-terminal caspase recruitment domain (ASC), caspase-1, and IL-1ß. Immunostaining techniques revealed increased expression of the NLRP3 inflammasome in microglial cells in the hippocampus of septic mice. Meanwhile, an in vitro model of primary microglia stimulated with LPS exhibited an increase in mitochondrial reactive oxygen species (ROS) production, NLRP3 complex recruitment, and IL-1ß release. Pharmacological inhibition of NLRP3, caspase-1, and mitochondrial ROS all decreased IL-1ß secretion by microglial cells. Furthermore, we found that microglial NLRP3 activation is the main pathway for IL-1ß-enriched microvesicle (MV) release, which is caspase-1-dependent. MV released from LPS-activated microglia induced neurite suppression and excitatory synaptic loss in neuronal cultures. Moreover, microglial caspase-1 inhibition prevented neurite damage and attenuated synaptic deficits induced by the activated microglial MV. These results suggest that microglial NLRP3 inflammasome activation is the mechanism of IL-1ß-enriched MV release and potentially synaptic impairment in sepsis.


Assuntos
Encefalopatia Associada a Sepse , Sepse , Animais , Camundongos , Caspase 1/metabolismo , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos Endogâmicos NOD , Microglia/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sepse/complicações , Sepse/metabolismo , Encefalopatia Associada a Sepse/metabolismo
2.
Front Cell Infect Microbiol ; 12: 975931, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36093188

RESUMO

Chagas disease (CD), a neglected tropical disease caused by the protozoan parasite Trypanosoma cruzi, is an important public health problem mainly in Latin America, leading to approximately 12,000 annual deaths. Current etiological treatment for CD is limited to two nitro compounds, benznidazole (Bz) and nifurtimox (Nif), both presenting relevant limitations. Different approaches have been employed to establish more effective and safer schemes to treat T. cruzi infection, mostly based on drug repurposing and combination therapies. Amiodarone (AMD), an antiarrhythmic medicament of choice for patients with the chronic cardiac form of CD, is also recognized as a trypanocidal agent. Therefore, our aim is to investigate the combined treatment Bz + AMD on trypomastigote viability, control of T. cruzi intracellular form proliferation, and recovery of the infection-induced cytoskeleton alterations in cardiac cells. The combination of Bz + AMD did not improve the direct trypanocidal effect of AMD on the infective blood trypomastigote and replicative intracellular forms of the parasite. Otherwise, the treatment of T. cruzi-infected cardiac cells with Bz plus AMD attenuated the infection-triggered cytoskeleton damage of host cells and the cytotoxic effects of AMD. Thus, the combined treatment Bz + AMD may favor parasite control and hamper tissue damage.


Assuntos
Amiodarona , Doença de Chagas , Tripanossomicidas , Trypanosoma cruzi , Amiodarona/farmacologia , Amiodarona/uso terapêutico , Doença de Chagas/tratamento farmacológico , Doença de Chagas/parasitologia , Citoesqueleto , Humanos , Nitroimidazóis , Tripanossomicidas/farmacologia
3.
Sci Rep ; 11(1): 14029, 2021 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-34234237

RESUMO

Toxoplasma gondii is an opportunistic protozoan pathogen with a wide geographic distribution. The chronic phase of toxoplasmosis is often asymptomatic in humans and is characterized by tissue cysts throughout the central nervous system and muscle cells. T. gondii and other pathogens with tropism for the central nervous system are considered risk factors in the etiology of several neuropsychiatric disorders, such as schizophrenia and bipolar disorder, besides neurological diseases. Currently, it is known that cerebral toxoplasmosis increases dopamine levels in the brain and it is related to behavioral changes in animals and humans. Here we evaluate whether chronic T. gondii infection, using the cystogenic ME-49 strain, could induce behavioral alterations associated with neuropsychiatric disorders and glutamatergic neurotransmission dysfunction. We observed that the startle amplitude is reduced in the infected animals as well as glutamate and D-serine levels in prefrontal cortical and hippocampal tissue homogenates. Moreover, we did not detect alterations in social preference and spontaneous alternation despite severe motor impairment. Thus, we conclude that behavioral and cognitive aspects are maintained even though severe neural damage is observed by chronic infection of C57Bl/6 mice with the ME-49 strain.


Assuntos
Ácido Glutâmico/metabolismo , Transtornos Mentais/etiologia , Transtornos Mentais/metabolismo , Reflexo de Sobressalto , Serina/metabolismo , Toxoplasmose Cerebral/complicações , Toxoplasmose Cerebral/parasitologia , Animais , Comportamento Animal , Peso Corporal , Encéfalo/metabolismo , Encéfalo/parasitologia , Encéfalo/patologia , Hipocampo/metabolismo , Transtornos Mentais/diagnóstico , Transtornos Mentais/psicologia , Camundongos , Neurotransmissores/metabolismo , Córtex Pré-Frontal/metabolismo , Comportamento Social , Toxoplasma
5.
Parasitol Res ; 119(1): 291-298, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31820167

RESUMO

We describe three new coccidian species of the genus Eimeria Schneider 1875 (Apicomplexa: Eimeriidae) and redescribe and report Eimeria zygodontomyis Lainson and Shaw, 1990 in the montane grass mouse, Akodon montensis Thomas, 1913 from the Serra dos Órgãos National Park in southeastern Brazil. Sporulated oocysts of Eimeria zygodontomyis are ellipsoidal to cylindrical with a 0.6 (0.5-0.8) µm thick very delicate bi-layered wall; length × width (n = 49) 18.3 × 12.5 (16-20 × 11-13) µm; length/width ratio of 1.4 (1.2-1.6); 1 polar granule occasionally present; micropyle, residuum both absent. Sporocysts are ellipsoidal; length × width 8.5 × 5.2 (8-11 × 5-6) µm; length/width ratio of 1.5 (1.3-1.7) µm; Stieda body is prominent; sub-Stieda body is absent; sporocyst residuum is compact. Sporulated oocysts of Eimeria montensis n. sp. are spheroidal to subspheroidal with a 1.2 (1.0-1.4) µm thick bi-layered wall; outer layer lightly pitted; length × width (n = 30) 16.3 × 12.5 (15-17 × 13-15) µm; length/width ratio of 1.3 (1.0-1.4); 1 polar granule present; micropyle, residuum both absent. Sporocysts are ellipsoidal; length × width 7.2 × 5.1 (6-8 × 4-6) µm; length/width ratio of 1.4 (1.2-1.6); Stieda body is present, sub-Stieda body is absent; sporocyst residuum consists of small, scattered granules. Sporulated oocysts of Eimeria uricanensis n. sp. are ovoidal to pyriform with a 1.4 ( 1.3-1.6) µm thick bi-layered wall; outer layer lightly pitted; length × width (n = 40) 26.6 × 18.6 (23-30 × 17-20) µm; length/width ratio of 1.4 (1.3-1.6); 1 polar granule present; micropyle, residuum both absent. Sporocysts are ellipsoidal, length × width 13.3 × 8.0 (10-16 × 7-9) µm; length/width ratio of 1.7 (1.5-1.9); Stieda body, sub-Stieda body both absent; sporocyst residuum consists of a cluster of granules, forming a spheroid mass. Sporulated oocysts of Eimeria parnasiensis n. sp. are subspheroidal to ellipsoidal with a 1.8 ( 1.3-2.4) µm thick bi-layered wall; outer layer lightly pitted; length × width (n = 54) 28.2 × 21.9 (26-32 × 19-28) µm; length/width ratio of 1.3 (1.2-1.4); 1 polar granule present; micropyle is absent; oocyst residuum is present and consists of a cluster of granules of varying thickness. Sporocysts are ovoidal, tapering towards the Stieda body; length × width 12.2 × 7.6 (10-13 × 6-9) µm; length/width ratio of 1.6 (1.4-1.9); Stieda body is present; sub-Stieda body is absent; sporocyst residuum is present and consists of an aggregate of thin granules.


Assuntos
Coccidiose/veterinária , Eimeria/classificação , Doenças dos Roedores/parasitologia , Sigmodontinae/parasitologia , Animais , Brasil , Coccidiose/parasitologia , Eimeria/citologia , Fezes/parasitologia , Oocistos/citologia , Parques Recreativos
6.
Artigo em Inglês | MEDLINE | ID: mdl-31828046

RESUMO

Toxoplasma gondii is the causative agent of toxoplasmosis, a parasitic disease with a wide global prevalence. The parasite forms cysts in skeletal muscle cells and neurons, although no evident association with inflammatory infiltrates has been typically found. We studied the impact of T. gondii infection on the myogenic program of mouse skeletal muscle cells (SkMC). The C2C12 murine myoblast cell line was infected with T. gondii tachyzoites (ME49 strain) for 24 h followed by myogenic differentiation induction. T. gondii infection caused a general decrease in myotube differentiation, fusion and maturation, along with decreased expression of myosin heavy chain. The expression of Myogenic Regulatory Factors Myf5, MyoD, Mrf4 and myogenin was modulated by the infection. Infected cultures presented increased proliferation rates, as assessed by Ki67 immunostaining, whereas neither host cell lysis nor apoptosis were significantly augmented in infected dishes. Cytokine Bead Array indicated that IL-6 and MCP-1 were highly increased in the medium from infected cultures, whereas TGF-ß1 was consistently decreased. Inhibition of the IL-6 receptor or supplementation with recombinant TGF-ß failed to reverse the deleterious effects caused by the infection. However, conditioned medium from infected cultures inhibited myogenesis in C2C12 cells. Activation of the Wnt/ß-catenin pathway was impaired in T. gondii-infected cultures. Our data indicate that T. gondii leads SkMCs to a pro-inflammatory phenotype, leaving cells unresponsive to ß-catenin activation, and inhibition of the myogenic differentiation program. Such deregulation may suggest muscle atrophy and molecular mechanisms similar to those involved in myositis observed in human patients.


Assuntos
Interações Hospedeiro-Patógeno , Desenvolvimento Muscular , Fatores de Regulação Miogênica/metabolismo , Toxoplasma/fisiologia , Toxoplasmose/metabolismo , Animais , Biomarcadores , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Imunofluorescência , Expressão Gênica , Genes Reporter , Camundongos , Mioblastos Esqueléticos/metabolismo , Mioblastos Esqueléticos/parasitologia , Fatores de Regulação Miogênica/genética , Toxoplasmose/parasitologia , Via de Sinalização Wnt
7.
Exp Parasitol ; 207: 107789, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31669169

RESUMO

American visceral leishmaniasis is caused by the protozoan Leishmania infantum. The control of the disease depends on the magnitude of the Th1 cell response and IL-10 producing regulatory T cells. Administration of chemokine, such as CXCL10, has shown promising results in the leishmaniasis treatment. Previous studies from our group have shown that CXCL10 induces a reduction in parasite burden in the spleen and a decrease in IL-10 and TGF-ß production in L. infantum-infected BALB/c mice. This work investigated whether CXCL10-treatment reduces IL-10 + Treg cell populations (CD4+CD25+Foxp3+ and Tr1) and induces morphological changes in the spleen. BALB/c mice were infected and treated or not with CXCL10 on the 1st, 3rd and 7th days of infection. CXCL10-treatment was able to reduce the parasite load in the spleen in L. infantum-infected BALB/c mice and this decrease in the number of parasites correlated with the decrease in size of this organ in treated animals compared to untreated animals. 7, 23, and 45 days post-treatment (p.t.), the phenotype and frequency of IL-10 + Treg cells were evaluated by flow cytometry, and the morphological changes of the spleen were analyzed by optical microscopy. After 7 and 23 days p.t., CXCL10-treated animals showed a significant reduction of CD25-Foxp3-IL-10+ (Tr1) cells in the spleen when compared to untreated animals, whereas CD4+CD25+Foxp3+IL-10+ Treg cells reduced later at 23rd and 45th days p.t. Furthermore, while untreated animals showed a significant positive correlation between IL-10 production and Tr1 cells, in CXCL10-treated group this correlation was negative. Thus, these findings show that treatment with CXCL10 chemokine in L. infantum-infected BALB/c mice results in suppression of IL10+ Treg (Foxp3+ and Tr1) cells in the spleen, associated with a reduction in parasite load and splenomegaly.


Assuntos
Quimiocina CXCL10/uso terapêutico , Leishmaniose Visceral/tratamento farmacológico , Leishmaniose Visceral/imunologia , Baço/imunologia , Linfócitos T Reguladores/efeitos dos fármacos , Adjuvantes Imunológicos/uso terapêutico , Animais , Quimiocina CXCL10/administração & dosagem , Quimiocina CXCL10/farmacologia , Cricetinae , Citometria de Fluxo , Fatores de Transcrição Forkhead/imunologia , Humanos , Injeções Intraperitoneais , Leishmania infantum/efeitos dos fármacos , Leishmania infantum/imunologia , Leishmania infantum/patogenicidade , Masculino , Mesocricetus , Camundongos , Camundongos Endogâmicos BALB C , Tamanho do Órgão/efeitos dos fármacos , Tamanho do Órgão/imunologia , Carga Parasitária , Baço/parasitologia , Baço/patologia , Linfócitos T Reguladores/imunologia , Virulência
8.
Rev Bras Parasitol Vet ; 27(1): 42-51, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29641790

RESUMO

Helminth parasites have been studied as potential accumulators for different pollutants. Echinostoma paraensei is a foodborne trematode whose vertebrate host, the rodent Nectomys squamipes, is naturally exposed to environmental pesticides. However, little information exists regarding the pesticide's effects on helminths. This study investigated the morphological effects on the trematode, E. paraensei, after experimental Roundup® herbicide exposure, in concentrations below those recommended for agricultural use. After two hours of exposure, scanning electron microscopy (SEM) showed changes to the tegument, such as furrowing, shrinkage, peeling, spines loss on the peristomic collar, and histopathological evidence of altered cells in the cecum and acinus vitelline glands with vacuoles and structural changes to the muscular layers. Glycidic content was decreased, primarily in the connective tissue. As E. paraensei is an intestinal parasite of the semi-aquatic wild rodent, N. squamipes, it is predisposed to pesticide exposure resulting from agricultural practices. Therefore, we emphasize the need to evaluate its impact on helminth parasites, due to their pivotal role in regulating host populations.


Assuntos
Echinostoma/anatomia & histologia , Echinostoma/efeitos dos fármacos , Glicina/análogos & derivados , Herbicidas/farmacologia , Animais , Echinostoma/ultraestrutura , Glicina/farmacologia , Microscopia Eletrônica de Varredura
9.
Acta Parasitol ; 63(2): 287-298, 2018 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-29654686

RESUMO

Balantioides coli is a ciliated protozoon that inhabits the intestine of pigs, non-human primates and humans. Light microscopy studies have described over 50 species of the genus Balantioides but their validity is in doubt. Due to the limited information about this genus, this study is aimed to identify morphological characteristics of Balantioides coli isolated using fluorescence microscopy and both scanning (SEM) and transmission electron microscopy (TEM). Trophozoites isolated from the feces of pig and macaque were washed and subjected to centrifugation. These cells were fixed with paraformaldehyde for immunofluorescence. Other aliquots of these trophozoites were fixed with glutaraldehyde, post fixed with osmium tetroxide and processed for SEM and TEM. Immunofluorescence studies revealed microtubules with a longitudinal distribution to the main axis of the parasite and in the constitution of cilia. SEM demonstrated a high concentration of cilia covering the oral apparatus and a poor presence of such structures in cytopyge. TEM revealed in the plasma membrane, several associated structures were observed to delineate the cellular cortex and mucocysts. The cytoskeleton of the oral region was observed in detail and had an organization pattern consisting of microtubules, which formed files and nematodesmal networks. Organelles such as hydrogenosomes like and peroxisomes were observed close to the cortex. Macronuclei were observed, but structures that were consistent with micronuclei were not identified. Ultrastructural morphological analysis of isolates confirms its similarity to Balantioides coli. In this study were identified structures that had not yet been described, such as hydrogenosomes like and cytoskeletal structures.


Assuntos
Parasitos/anatomia & histologia , Parasitos/ultraestrutura , Primatas/parasitologia , Suínos/parasitologia , Trofozoítos/ultraestrutura , Animais , Membrana Celular/ultraestrutura , Fezes/parasitologia , Humanos , Intestinos/parasitologia , Microscopia Eletrônica de Varredura/métodos , Microscopia Eletrônica de Transmissão/métodos , Microtúbulos/ultraestrutura , Organelas/ultraestrutura , Parasitos/isolamento & purificação , Peroxissomos/ultraestrutura , Infecções Protozoárias em Animais/parasitologia , Trofozoítos/isolamento & purificação
10.
Rev. bras. parasitol. vet ; 27(1): 41-50, Jan.-Mar. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-899316

RESUMO

Abstract Helminth parasites have been studied as potential accumulators for different pollutants. Echinostoma paraensei is a foodborne trematode whose vertebrate host, the rodent Nectomys squamipes, is naturally exposed to environmental pesticides. However, little information exists regarding the pesticide's effects on helminths. This study investigated the morphological effects on the trematode, E. paraensei, after experimental Roundup® herbicide exposure, in concentrations below those recommended for agricultural use. After two hours of exposure, scanning electron microscopy (SEM) showed changes to the tegument, such as furrowing, shrinkage, peeling, spines loss on the peristomic collar, and histopathological evidence of altered cells in the cecum and acinus vitelline glands with vacuoles and structural changes to the muscular layers. Glycidic content was decreased, primarily in the connective tissue. As E. paraensei is an intestinal parasite of the semi-aquatic wild rodent, N. squamipes, it is predisposed to pesticide exposure resulting from agricultural practices. Therefore, we emphasize the need to evaluate its impact on helminth parasites, due to their pivotal role in regulating host populations.


Resumo Helmintos parasitos tem sido estudados como acumuladores potenciais para diferentes poluentes. O trematódeo E. paraensei tem como hospedeiro vertebrado o roedor Nectomys squamipes naturalmente exposto a pesticidas no meio ambiente. No entanto, pouca informação está disponível sobre os efeitos dos pesticidas em helmintos parasitos. O presente estudo investigou, em condições experimentais, os efeitos morfológicos no trematódeo E. paraensei após a exposição ao herbicida Roundup®, em concentrações abaixo das recomendadas para a utilização agrícola. A microscopia eletrônica de varredura (MEV) mostrou após duas horas de exposição, alterações no tegumento, como enrugamento, contração e descamação com perda de espinhos no colar peristômico e análise histopatológica evidenciou células do ceco alteradas, as glândulas vitelínicas com vacúolos e mudanças estruturais nas camadas musculares. Diminuição do conteúdo glicídico, principalmente no tecido conjuntivo, também foi observado. Considerando a predisposição à exposição a pesticidas agrícolas de N. squamipes infectado por E. paraensei, são necessários estudos para avaliar o impacto de tais resíduos frente aos helmintos e seus hospedeiros.


Assuntos
Animais , Echinostoma/anatomia & histologia , Echinostoma/efeitos dos fármacos , Glicina/análogos & derivados , Herbicidas/farmacologia , Microscopia Eletrônica de Varredura , Echinostoma/ultraestrutura , Glicina/farmacologia
11.
Parasitol Res ; 117(2): 371-376, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29230581

RESUMO

A total of 53 specimens of the montane grass mouse, Akodon montensis Thomas, 1913 were collected in the Serra dos Órgãos National Park (SONP) in November 2014 and July 2015. The fecal material was analyzed, and a prevalence of 7.5% was recorded for a new coccidian species of the genus Eimeria Schneider, 1875, with part of its endogenous development recorded in the small intestine. The oocysts of a new coccidian species of genus Eimeria are ellipsoidal to subspherical. The wall is bi-layered, c. 1.5 µm (1.3-1.6 µm) thick, outer layer rough. Oocyst (n = 126) mean length is 25.3 µm (21.0-28.0 µm), with a width of 20.2 µm (17.0-22.0 µm) and mean length/width (L:W) ratio of 1.3 (1.2-1.4). Polar granule is present, with the oocyst residuum as a large spherical to subspherical globule. Sporocyst shape (n = 126) is ellipsoidal, with a mean length of 11.8 µm (9.3-14.4 µm), width of 7.9 µm (6.7-9.3 µm), and mean L:W ratio of 1.5 (1.4-1.7). Sporocysts with nipple-like Stieda body and sub-Stieda body are absent. A sporocyst residuum formed by several globules, usually along the sporocyst wall. This is the first record of Eimeria in the montane grass mouse from Brazil.


Assuntos
Coccidiose/veterinária , Eimeria/classificação , Sigmodontinae/parasitologia , Animais , Brasil , Coccidiose/parasitologia , Eimeria/isolamento & purificação , Fezes/parasitologia , Masculino , Oocistos
12.
Mem Inst Oswaldo Cruz ; 112(8): 561-568, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28767981

RESUMO

BACKGROUND: Visceral leishmaniasis (VL) caused by Leishmania infantum is characterised by the loss of the ability of the host to generate an effective immune response. Chemokines have a direct involvement in the pathogenesis of leishmaniasis, causing a rapid change in the expression of these molecules during infection by Leishmania. OBJECTIVES: Herein, it was investigated the role of CXCL10 in controlling infection by L. infantum. METHODS: RAW 264.7 macrophages were infected with L. infantum in vitro and treated or not with CXCL10 (25, 50 and 100 ng/mL). Parasite load, as well as nitric oxide (NO), IL-4 and IL-10 production were assessed at 24 and 48 h after infection. In vivo, BALB/c mice were infected and treated or not with CXCL10 (5 µg/kg) at one, three and seven days of infection. Parasite load, IFN-g, IL-4, TGF-ß and IL-10 were evaluated one, seven and 23 days post treatment. FINDINGS: In vitro, CXCL10 reduced parasitic load, not dependent on NO, and inhibited IL-10 and IL-4 secretion. In vivo, CXCL10 was able to reduce the parasite load in both liver and spleen, four weeks after infection, representing a higher decrease in the number of parasites in these organs, also induced IFN-γ at day 23 after treatment, correlating with the decrease in parasite load, and reduced IL-10 and TGF-ß. MAIN CONCLUSIONS: This study suggests a partial protective role of CXCL10 against L. infantum, mediated by IFN-g, not dependent on NO, and with suppression of IL-10 and TGF-ß. These data may provide information for the development of new approaches for future therapeutic interventions for VL.


Assuntos
Quimiocina CXCL10/uso terapêutico , Citocinas/imunologia , Leishmania infantum , Leishmaniose Visceral/tratamento farmacológico , Macrófagos/efeitos dos fármacos , Animais , Interferon gama/análise , Interleucina-10/biossíntese , Interleucina-4/biossíntese , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/parasitologia , Fígado/parasitologia , Fígado/patologia , Macrófagos/metabolismo , Macrófagos/parasitologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico/biossíntese , Tamanho do Órgão , Baço/metabolismo , Baço/parasitologia , Baço/patologia , Fatores de Tempo , Fator de Crescimento Transformador beta/análise
13.
Mem. Inst. Oswaldo Cruz ; 112(8): 561-568, Aug. 2017. graf
Artigo em Inglês | LILACS | ID: biblio-894865

RESUMO

BACKGROUND Visceral leishmaniasis (VL) caused by Leishmania infantum is characterised by the loss of the ability of the host to generate an effective immune response. Chemokines have a direct involvement in the pathogenesis of leishmaniasis, causing a rapid change in the expression of these molecules during infection by Leishmania. OBJECTIVES Herein, it was investigated the role of CXCL10 in controlling infection by L. infantum. METHODS RAW 264.7 macrophages were infected with L. infantum in vitro and treated or not with CXCL10 (25, 50 and 100 ng/mL). Parasite load, as well as nitric oxide (NO), IL-4 and IL-10 production were assessed at 24 and 48 h after infection. In vivo, BALB/c mice were infected and treated or not with CXCL10 (5 μg/kg) at one, three and seven days of infection. Parasite load, IFN-g, IL-4, TGF-β and IL-10 were evaluated one, seven and 23 days post treatment. FINDINGS In vitro, CXCL10 reduced parasitic load, not dependent on NO, and inhibited IL-10 and IL-4 secretion. In vivo, CXCL10 was able to reduce the parasite load in both liver and spleen, four weeks after infection, representing a higher decrease in the number of parasites in these organs, also induced IFN-γ at day 23 after treatment, correlating with the decrease in parasite load, and reduced IL-10 and TGF-β. MAIN CONCLUSIONS This study suggests a partial protective role of CXCL10 against L. infantum, mediated by IFN-g, not dependent on NO, and with suppression of IL-10 and TGF-β. These data may provide information for the development of new approaches for future therapeutic interventions for VL.


Assuntos
Animais , Masculino , Camundongos , Tamanho do Órgão/fisiologia , Interleucina-4/biossíntese , Interleucina-10/biossíntese , Leishmania infantum , Quimiocina CXCL10/uso terapêutico , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/parasitologia , Leishmaniose Visceral/tratamento farmacológico , Fígado/patologia , Macrófagos/efeitos dos fármacos , Citocinas/imunologia , Interferon gama/análise , Camundongos Endogâmicos BALB C
14.
Braz. j. microbiol ; 48(1): 118-124, Jan.-Mar. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-839334

RESUMO

Abstract Staphylococcus spp. play an important role in the etiology of bovine mastitis. Staphylococcus aureus is considered the most relevant species due to the production of virulence factors such as slime, which is required for biofilm formation. This study aimed to evaluate biofilm production and its possible relation to beta-lactamic resistance in 20 S. aureus isolates from bovine mastitic milk. The isolates were characterized by pheno-genotypic and MALDI TOF-MS assays and tested for genes such as icaA, icaD, bap, agr RNAIII, agr I, agr II, agr III, and agr IV, which are related to slime production and its regulation. Biofilm production in microplates was evaluated considering the intervals determined along the bacterial growth curve. In addition, to determine the most suitable time interval for biofilm analysis, scanning electron microscopy was performed. Furthermore, genes such as mecA and blaZ that are related to beta-lactamic resistance and oxacillin susceptibility were tested. All the studied isolates were biofilm producers and mostly presented icaA and icaD. The Agr type II genes were significantly prevalent. According to the SEM, gradual changes in the bacterial arrangement were observed during biofilm formation along the growth curve phases, and the peak was reached at the stationary phase. In this study, the penicillin resistance was related to the production of beta-lactamase, and the high minimal bactericidal concentration for cefoxitin was possibly associated with biofilm protection. Therefore, further studies are warranted to better understand biofilm formation, possibly contributing to our knowledge about bacterial resistance in vivo.


Assuntos
Animais , Feminino , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia , Biofilmes , Resistência beta-Lactâmica , Mastite Bovina/microbiologia , Antibacterianos/farmacologia , Staphylococcus aureus/ultraestrutura , Proteínas de Bactérias/genética , Bovinos , Testes de Sensibilidade Microbiana , Transativadores/genética , Proteoma , Fatores de Virulência/genética , Proteômica/métodos , Estudos de Associação Genética
15.
Braz J Microbiol ; 48(1): 118-124, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27913076

RESUMO

Staphylococcus spp. play an important role in the etiology of bovine mastitis. Staphylococcus aureus is considered the most relevant species due to the production of virulence factors such as slime, which is required for biofilm formation. This study aimed to evaluate biofilm production and its possible relation to beta-lactamic resistance in 20 S. aureus isolates from bovine mastitic milk. The isolates were characterized by pheno-genotypic and MALDI TOF-MS assays and tested for genes such as icaA, icaD, bap, agr RNAIII, agr I, agr II, agr III, and agr IV, which are related to slime production and its regulation. Biofilm production in microplates was evaluated considering the intervals determined along the bacterial growth curve. In addition, to determine the most suitable time interval for biofilm analysis, scanning electron microscopy was performed. Furthermore, genes such as mecA and blaZ that are related to beta-lactamic resistance and oxacillin susceptibility were tested. All the studied isolates were biofilm producers and mostly presented icaA and icaD. The Agr type II genes were significantly prevalent. According to the SEM, gradual changes in the bacterial arrangement were observed during biofilm formation along the growth curve phases, and the peak was reached at the stationary phase. In this study, the penicillin resistance was related to the production of beta-lactamase, and the high minimal bactericidal concentration for cefoxitin was possibly associated with biofilm protection. Therefore, further studies are warranted to better understand biofilm formation, possibly contributing to our knowledge about bacterial resistance in vivo.


Assuntos
Antibacterianos/farmacologia , Biofilmes , Mastite Bovina/microbiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia , Resistência beta-Lactâmica , Animais , Proteínas de Bactérias/genética , Bovinos , Feminino , Estudos de Associação Genética , Testes de Sensibilidade Microbiana , Proteoma , Proteômica/métodos , Staphylococcus aureus/ultraestrutura , Transativadores/genética , Fatores de Virulência/genética
16.
Inflamm Res ; 65(11): 869-879, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27379721

RESUMO

OBJECTIVE AND DESIGN: ß-Caryophyllene (BCP) is a sesquiterpene that binds to the cannabinoid 2 (CB2) receptor and exerts anti-inflammatory effects. In this study, we investigated the anti-inflammatory effect of BCP and another CB2 agonist, GP1a in inflammatory experimental model induced by Mycobacterium bovis (BCG). METHODS: C57Bl/6 mice were pretreated orally with BCP (0.5-50 mg/kg) or intraperitonealy with GP1a (10 mg/kg) 1 h before the induction of pleurisy or pulmonary inflammation by BCG. The direct action of CB2 agonists on neutrophils function was evaluated in vitro. RESULTS: ß-Caryophyllene (50 mg/kg) impaired BCG-induced neutrophil accumulation in pleurisy without affecting mononuclear cells or the production of TNF-α and CCL2/MCP-1. However, BCP inhibited CXCL1/KC, leukotriene B4 (LTB4), IL-12, and nitric oxide production. GP1a had a similar effect to BCP. Preincubation of neutrophils with BCP (10 µM) impaired chemotaxis toward LTB4 and adhesion to endothelial cells stimulated with TNF-α, and both, BCP and GP1a, impaired LTB4-induced actin polymerization. CONCLUSION: These results suggest that the CB2 receptor may represent a new target for modulating the inflammatory reaction induced by mycobacteria.


Assuntos
Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Receptor CB2 de Canabinoide/agonistas , Sesquiterpenos/farmacologia , Sesquiterpenos/uso terapêutico , Tuberculose Pulmonar/tratamento farmacológico , Actinas/metabolismo , Animais , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Citocinas/imunologia , Dinoprostona/metabolismo , Macrófagos/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Mycobacterium bovis , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Neutrófilos/fisiologia , Óxido Nítrico/metabolismo , Pleurisia/tratamento farmacológico , Pleurisia/imunologia , Pneumonia/tratamento farmacológico , Pneumonia/imunologia , Sesquiterpenos Policíclicos , Tuberculose Pulmonar/imunologia
17.
Parasitol Res ; 115(7): 2853-61, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27075305

RESUMO

Toxoplasma gondii is an obligate intracellular protozoan parasite, the causative agent of toxoplasmosis, one of the most widespread zoonoses in the world. During the host immune response, tissue cysts are formed, allowing the maintenance of the parasite within the host cell. Autophagy, a degradation process of cellular components, is critical for cellular homeostasis. Recently, it has been proposed that autophagy participates in host-pathogen interactions. Autophagic inducers (rapamycin or glucose plus serum deprivation) inhibited infection and parasite proliferation in a clinically relevant model of primary skeletal muscle cells (SkMC). The ultrastructural analysis showed in SkMC submitted to autophagic stimuli the presence of structures suggestive of autophagosomes close to the parasitophorous vacuole containing degraded parasites. Fluorescence microscopy results pointed out the increase in LC3 puncta in these cells after incubation with autophagic inducers. In the present study, SkMC autophagy controlled the proliferation of tachyzoites inside the cell, data reinforced by ultrastructural evidences and increased LC3 expression.


Assuntos
Autofagia/efeitos dos fármacos , Interações Hospedeiro-Patógeno , Proteínas Associadas aos Microtúbulos/metabolismo , Músculo Esquelético/parasitologia , Toxoplasma/ultraestrutura , Toxoplasmose/parasitologia , Animais , Autofagossomos/efeitos dos fármacos , Autofagossomos/ultraestrutura , Biomarcadores/metabolismo , Células Cultivadas , Feminino , Glucose/metabolismo , Camundongos , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Músculo Esquelético/citologia , Músculo Esquelético/fisiologia , Músculo Esquelético/ultraestrutura , Sirolimo/farmacologia , Toxoplasma/fisiologia , Toxoplasmose/tratamento farmacológico , Toxoplasmose/imunologia , Vacúolos/parasitologia , Vacúolos/fisiologia , Vacúolos/ultraestrutura
19.
In. Araújo-Jorge, Tania Cremonini de; Barbosa, Helene Santos; Oliveira, Ricardo Lourenço de. Uma escola para a ciência e a saúde: 111 anos de ensino no Instituto Oswaldo Cruz. Rio de Janeiro, Fiocruz, 2012. p.62-69, ilus, tab.
Monografia em Português | LILACS | ID: lil-653122

RESUMO

A segunda fase do ensino no Instituto Oswaldo Cruz coincide com o turbulento período que se seguiu ao "Massacre de Manguinhos". A criação da Fundação Instituto Oswaldo Cruz mudou profundamente o regime administrativo do IOC, fusionando a outras três instituições (ENSP, IFF e INERU). O ensino no Instituto manteve a filosofia de Oswaldo Cruz de integrar pesquisa e ensino para enfrentar os principais problemas de saúde pública. Neste sentido, os programas de pós-graduação expandiram-se e consolidaram-se com lugar de destaque no sistema de ensino superior do país.


Assuntos
História do Século XX , História do Século XXI , Academias e Institutos/história , Ciência/história , Universidades , Educação em Saúde/história , Capacitação Profissional , Saúde Pública/história , Brasil
20.
In. Araújo-Jorge, Tania Cremonini de; Barbosa, Helene Santos; Oliveira, Ricardo Lourenço de. Uma escola para a ciência e a saúde: 111 anos de ensino no Instituto Oswaldo Cruz. Rio de Janeiro, Fiocruz, 2012. p.52-61, ilus, tab.
Monografia em Português | LILACS | ID: lil-653123

RESUMO

A vocação para o ensino e a formação de recursos humanos para a ciência e a saúde está presente desde a criação do Instituto Soroterápico Federal de Manguinhos, em 25 de maio de 1900. Com o objetivo inicial de produzir soros e vacinas para combater a peste bubônica na virada do século, o Instituto foi a primeira iniciativa científico-tecnológica do país, e também deu início a uma longa tradição de formação de pesquisadores e profissionais para a Saúde e a Ciência, antes da criação da pós-graduação no Brasil, tal como se conhece hoje. Por isso se fala de tríade estrutural da Fundação Oswaldo Cruz: dessas três vertentes, e assim são o desenvolvimento tecnológico, a informação e a comunicação em ciência e saúde, a assistência e os serviços de laboratórios de referência, a cooperação nacional e internacional. Referência em qualquer tema desde que a pesquisa realizada seja de qualidade e que nela se formem pessoas, com o sentido de retorno desses conhecimentos para a sociedade.


Assuntos
História do Século XX , Academias e Institutos/história , Ciência/história , Universidades , Educação em Saúde/história , Capacitação Profissional , Saúde Pública/história , Brasil
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