RESUMO
The receptor for colony stimulating factor 1 (CSF-1R) is important for the survival and function of myeloid cells that mediate pathology during experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). CSF-1 and IL-34, the ligands of CSF-1R, have similar bioactivities but distinct tissue and context-dependent expression patterns, suggesting that they have different roles. This could be the case in EAE, given that CSF-1 expression is up-regulated in the CNS, while IL-34 remains constitutively expressed. We found that targeting CSF-1 with neutralizing antibody halted ongoing EAE, with efficacy superior to CSF-1R inhibitor BLZ945, whereas IL-34 neutralization had no effect, suggesting that pathogenic myeloid cells were maintained by CSF-1. Both antiCSF-1 and BLZ945 treatment greatly reduced the number of monocyte-derived cells and microglia in the CNS. However, antiCSF-1 selectively depleted inflammatory microglia and monocytes in inflamed CNS areas, whereas BLZ945 depleted virtually all myeloid cells, including quiescent microglia, throughout the CNS. AntiCSF-1 treatment reduced the size of demyelinated lesions and microglial activation in the gray matter. Lastly, we found that bone marrowderived immune cells were the major mediators of CSF-1Rdependent pathology, while microglia played a lesser role. Our findings suggest that targeting CSF-1 could be effective in ameliorating MS pathology, while preserving the homeostatic functions of myeloid cells, thereby minimizing risks associated with ablation of CSF-1Rdependent cells.
Assuntos
Encefalomielite Autoimune Experimental , Fator Estimulador de Colônias de Macrófagos , Esclerose Múltipla , Animais , Benzotiazóis/farmacologia , Benzotiazóis/uso terapêutico , Sistema Nervoso Central/imunologia , Encefalomielite Autoimune Experimental/tratamento farmacológico , Encefalomielite Autoimune Experimental/imunologia , Fator Estimulador de Colônias de Macrófagos/antagonistas & inibidores , Fator Estimulador de Colônias de Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/imunologia , Células Mieloides/efeitos dos fármacos , Células Mieloides/metabolismo , Ácidos Picolínicos/farmacologia , Ácidos Picolínicos/uso terapêutico , Receptor de Fator Estimulador de Colônias de Macrófagos/antagonistas & inibidoresRESUMO
Multiple sclerosis (MS) is a chronic demyelinating disease of the central nervous system (CNS). MS and its animal model called experimental autoimmune encephalomyelitis (EAE) immunopathogenesis involve a plethora of immune cells whose activation releases a variety of proinflammatory mediators and free radicals. Vitamin D3 (VitD) is endowed with immunomodulatory and antioxidant properties that we demonstrated to control EAE development. However, this protective effect triggered hypercalcemia. As such, we compared the therapeutic potential of VitD and paricalcitol (Pari), which is a non-hypercalcemic vitamin D analog, to control EAE. From the seventh day on after EAE induction, mice were injected with VitD or Pari every other day. VitD, but not Pari, displayed downmodulatory ability being able to reduce the recruitment of inflammatory cells, the mRNA expression of inflammatory parameters, and demyelination at the CNS. Lower production of proinflammatory cytokines by lymph node-derived cells and IL-17 by gut explants, and reduced intestinal inflammation were detected in the EAE/VitD group compared to the EAE untreated or Pari groups. Dendritic cells (DCs) differentiated in the presence of VitD developed a more tolerogenic phenotype than in the presence of Pari. These findings suggest that VitD, but not Pari, has the potential to be used as a preventive therapy to control MS severity.
Assuntos
Antioxidantes/administração & dosagem , Colecalciferol/administração & dosagem , Encefalomielite Autoimune Experimental/prevenção & controle , Ergocalciferóis/administração & dosagem , Fatores Imunológicos/administração & dosagem , Profilaxia Pós-Exposição/métodos , Animais , Antioxidantes/farmacologia , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/imunologia , Colecalciferol/farmacologia , Citocinas/metabolismo , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Encefalomielite Autoimune Experimental/sangue , Encefalomielite Autoimune Experimental/imunologia , Ergocalciferóis/farmacologia , Feminino , Fatores Imunológicos/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Esclerose Múltipla/imunologia , Esclerose Múltipla/prevenção & controle , Índice de Gravidade de Doença , Transdução de Sinais/efeitos dos fármacos , Resultado do TratamentoRESUMO
The objective of our study was to evaluate the association between peptidylarginine deiminase 4 (PAD4) concentration and its polymorphisms with mortality in patients with septic shock. We prospectively evaluated 175 patients aged over 18 years with septic shock upon intensive care unit (ICU) admission. However, 48 patients were excluded. Thus, 127 patients were enrolled in the study. At the time of the patients' enrollment, demographic information was recorded. Blood samples were taken within the first 24 hours of the patient's admission to determine serum PAD4 concentrations and its polymorphism PADI4_89 [rs11203366], PADI4_94 [rs2240340] and PADI4_104 [rs1748033]. The mean age was 63.3 ± 15.2 years, 56.7% were male, PAD4 concentration was 4.62 (2.48-6.20) ng/mL and the ICU mortality rate was 67.7%. The patients who died in the ICU had higher APACHE II and Sequential Organ Failure Assessment (SOFA) scores. In addition, PAD4 concentration was higher in patients who died during ICU stay. However, there were no differences regarding PADI4 polymorphisms and ICU mortality. In the logistic regression models, PAD4 concentrations were associated with ICU mortality when adjusted for APACHE II score and lactate (OR: 1.477; CI 95%: 1.186-1.839; P < .001), and when adjusted for age, gender and APACHE II score (OR: 1.392; CI 95%: 1.145-1.692; P < .001). In conclusion, PAD4 concentration, but not PADI4_89, PADI4_94 and PADI4_104 polymorphisms, is associated with ICU mortality in septic shock patients.
Assuntos
Polimorfismo de Nucleotídeo Único , Desiminases de Arginina em Proteínas/genética , Choque Séptico/genética , Choque Séptico/mortalidade , APACHE , Idoso , Feminino , Expressão Gênica , Mortalidade Hospitalar/tendências , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Proteína-Arginina Desiminase do Tipo 4 , Desiminases de Arginina em Proteínas/sangue , Choque Séptico/sangue , Choque Séptico/patologia , Análise de SobrevidaRESUMO
Staphylococcus aureus is the most common agent of septic arthritis (SA) that is a severe, rapidly progressive and erosive disease. In this work we investigated the clinical, histopathological and immunological characteristics of the SA triggered by an enterotoxin C producer S. aureus strain. The effect of a ß-lactamic antibiotic over disease evolution and cytokine production was also evaluated. After confirmation that ATCC 19095 SEC(+) strain preserved its ability to produce enterotoxin C, this bacteria was used to infect C57BL/6 male mice. Body weight, clinical score and disease prevalence were daily evaluated during 14 days. Cytokine production by splenocytes, cytokine mRNA expression in arthritic lesions, transcription factors mRNA expression in inguinal lymph nodes and histopathological analysis were performed 7 and 14 days after infection. ATCC 19095 SEC(+) strain caused a severe arthritis characterized by weight loss, high clinical scores and a 100% disease prevalence. Histopathological analysis revealed inflammation, pannus formation and bone erosion. Arthritis aggravation was associated with elevated production of pro-inflammatory cytokines, higher local mRNA expression of these cytokines and also higher mRNA expression of T-bet, ROR-γ and GATA-3. Disease control by cloxacillin was associated with decreased production of pro-inflammatory cytokines but not of IL-10. These findings indicate that the ATCC 19095 SEC(+) strain is able to initiate a severe septic arthritis in mice associated with elevated cytokine production that can be, however, controlled by cloxacillin.
Assuntos
Antibacterianos/farmacologia , Artrite Infecciosa/tratamento farmacológico , Cloxacilina/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/patogenicidade , Animais , Artrite Experimental/tratamento farmacológico , Artrite Experimental/microbiologia , Artrite Experimental/patologia , Artrite Infecciosa/imunologia , Artrite Infecciosa/microbiologia , Artrite Infecciosa/patologia , Citocinas/genética , Citocinas/metabolismo , Enterotoxinas/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Staphylococcus aureus/metabolismo , Fatores de Transcrição/genéticaRESUMO
BACKGROUND: Bacterial superantigens are potent T cell activators that can activate T cells with specificity for antigens of the central nervous system (CNS). In this study, we compared the effect of two S. aureus strains on experimental autoimmune encephalomyelitis (EAE) development. C57BL/6 female mice were infected with S. aureus ATCC 51650, which produces toxic shock syndrome toxin 1 (TSST-1+) or S. aureus ATCC 43300, which does not produce toxins (TOX-). Three days later, the animals were subjected to EAE induction by immunization with myelin oligodendrocyte glycoprotein (MOG). The weight variation, disease incidence and clinical score were recorded daily. Cytokines and Foxp3+ regulatory T cells in the brain were evaluated during the acute disease phase. Cytokines and Foxp3+ regulatory T cells in the spleen and histopathological analysis of the CNS were assessed during the chronic stage. RESULTS: Previous infection with both strains similarly decreased the clinical score; however, only the TSST-1+ strain clearly diminished inflammation in the CNS. The infections also modulated cytokine production in the spleen and CNS. Reduced production of IL-5 and IL-10 was detected in MOG-stimulated spleen cultures in the TOX- and TSST-1+ infected groups, respectively. In S. aureus stimulated cultures, there was an increased production of IFN-γ and IL-10 in both infected groups and an increased level of IL-5 in the TSST-1+ group. CNS infiltrating cell cultures from previously infected mice produced less IL-17 in response to MOG and more IFN-γ in response to S. aureus stimulation. CONCLUSIONS: These results indicated that both strains attenuated clinical EAE manifestations, but only TSST-1 clearly decreased CNS inflammation.
Assuntos
Toxinas Bacterianas/imunologia , Encéfalo/imunologia , Encéfalo/patologia , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/terapia , Infecções Estafilocócicas/imunologia , Staphylococcus aureus/imunologia , Animais , Toxinas Bacterianas/uso terapêutico , Encefalomielite Autoimune Experimental/patologia , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Infecções Estafilocócicas/patologia , Staphylococcus aureus/classificaçãoRESUMO
BACKGROUND: Staphylococcus aureus is the most common agent of septic arthritis that is a severe, rapidly progressive and destructive joint disease. Superantigens produced by S. aureus are considered the major arthritogenic factors. In this study, we compared the arthritogenic potential of five superantigen-producing staphylococcal strains. METHODS: Male C57BL/6 mice were intravenously infected with ATCC 19095 SEC+, N315 ST5 TSST-1+, S-70 TSST-1+, ATCC 51650 TSST-1+ and ATCC 13565 SEA+ strains. Clinical parameters as body weight, arthritis incidence and clinical score were daily evaluated. Joint histopathological analysis and spleen cytokine production were evaluated at the 14th day after infection. RESULTS: Weight loss was observed in all infected mice. ATCC 19095 SEC+, N315 ST5 TSST-1+ and S-70 TSST-1+ were arthritogenic, being the highest scores observed in ATCC 19095 SEC+ infected mice. Intermediate and lower clinical scores were observed in N315 ST5 TSST-1+ and S-70 TSST-1+ infected mice, respectively. The ATCC 13565 SEA+ strain caused death of 85% of the animals after 48 h. Arthritis triggered by the ATCC 19095 SEC+ strain was characterized by accentuated synovial hyperplasia, inflammation, pannus formation, cartilage destruction and bone erosion. Similar joint alterations were found in N315 ST5 TSST-1+ infected mice, however they were strikingly more discrete. Only minor synovial proliferation and inflammation were triggered by the S-70 TSST-1+ strain. The lowest levels of TNF-α, IL-6 and IL-17 production in response to S. aureus stimulation were found in cultures from mice infected with the less arthritogenic strains (S-70 TSST-1+ and ATCC 51650 TSST-1+). The highest production of IL-17 was detected in mice infected with the most arthritogenic strains (ATCC 19095 SEC+ and N315 ST5 TSST-1+). CONCLUSIONS: Together these results demonstrated that S. aureus strains, isolated from biological samples, were able to induce a typical septic arthritis in mice. These results also suggest that the variable arthritogenicity of these strains was, at least in part, related to their differential ability to induce IL-17 production.
Assuntos
Artrite Infecciosa/microbiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/imunologia , Animais , Antígenos de Bactérias/imunologia , Artrite Infecciosa/imunologia , Humanos , Interleucina-17/imunologia , Interleucina-6/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Infecções Estafilocócicas/imunologia , Staphylococcus aureus/isolamento & purificação , Superantígenos/imunologiaRESUMO
A prime-boost strategy conserving BCG is considered the most promising vaccine to control tuberculosis. A boost with a DNA vaccine containing the mycobacterial gene of a heat shock protein (pVAXhsp65) after BCG priming protected mice against experimental tuberculosis. However, anti-hsp65 immunity could worsen an autoimmune disease due to molecular mimicry. In this investigation, we evaluated the effect of a previous BCG or BCG/pVAXhsp65 immunization on experimental autoimmune encephalomyelitis (EAE) development. Female Lewis rats were immunized with BCG or BCG followed by pVAXhsp65 boosters. The animals underwent EAE induction and were daily evaluated for weight loss and clinical score. They were euthanized during recovery phase to assess immune response and inflammatory infiltration at the central nervous system. Previous immunization did not aggravate or accelerate clinical score or weight loss. In addition, this procedure clearly decreased inflammation in the brain. BCG immunization modulated the host immune response by triggering a significant reduction in IL-10 and IFN-γ levels induced by myelin basic protein. These data indicated that vaccination protocols with BCG or BCG followed by boosters with pVAXhsp65 did not trigger a deleterious effect on EAE evolution.
Assuntos
Vacina BCG/imunologia , Encefalomielite Autoimune Experimental/imunologia , Mycobacterium bovis/imunologia , Tuberculose Bovina/prevenção & controle , Animais , Vacina BCG/administração & dosagem , Encéfalo/imunologia , Encéfalo/metabolismo , Encéfalo/patologia , Bovinos , Encefalomielite Autoimune Experimental/metabolismo , Encefalomielite Autoimune Experimental/patologia , Feminino , Interferon gama/biossíntese , Interleucina-10/biossíntese , Ratos , Medula Espinal/imunologia , Medula Espinal/metabolismo , Medula Espinal/patologiaRESUMO
Epidemiological and experimental studies support the idea that helminth infections can induce a protective effect against the development of autoimmune and allergic diseases. In this study we characterized the immune response induced by Strongyloides venezuelensis infection in C57BL/6 mice and then evaluated the effect of a previous contact with this helminth in the outcome of type 1 diabetes. Animals were initially infected with 2000 L3 larvae from S. venezuelensis and euthanized 22 days later. An acute phase, identified by a high amount of eggs per gram of feces, was established between days 7 and 9 post-infection. Recovery from infection was associated with a Th2 polarized response characterized by a significant level of serum IgG1 specific antibodies and also a significant production of IL-5 and IL-10 by spleen cells stimulated with S. venezuelensis soluble antigen. Immunization with soluble S. venezuelensis antigen associated with complete Freund's adjuvant followed by infection with S. venezuelensis protected mice from diabetes development induced by streptozotocin. Protection was characterized by a higher body weight gain, lower glycemic levels, much less severe insulitis and preserved insulin production. Together, these results indicate that S. venezuelensis contributed to protect C57BL/6 mice against experimental diabetes induced by streptozotocin.
Assuntos
Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Tipo 1/complicações , Strongyloides/imunologia , Estrongiloidíase/imunologia , Células Th2/imunologia , Animais , Anticorpos Anti-Helmínticos/sangue , Glicemia/metabolismo , Citocinas/metabolismo , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Tipo 1/imunologia , Fezes/parasitologia , Insulina/análise , Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Contagem de Ovos de Parasitas , Ratos , Ratos Wistar , Baço/imunologia , Estreptozocina , Estrongiloidíase/complicaçõesRESUMO
Experimental autoimmune encephalomyelitis (EAE) is an artificially induced demyelination of the central nervous system (CNS) that resembles multiple sclerosis in its clinical, histopathological, and immunological features. Activated Th1 and Th17 cells are thought to be the main immunological players during EAE development. This study was designed to evaluate peripheral and local contribution of IL-17 to acute and chronic EAE stages. C57BL/6 mice were immunized with MOG plus complete Freund's adjuvant followed by pertussis toxin. Mice presented an initial acute phase characterized by accentuated weight loss and high clinical score, followed by a partial recovery when the animals reached normal body weight and smaller clinical scores. Spleen cells stimulated with MOG produced significantly higher levels of IFN- γ during the acute period whereas similar IL-17 levels were produced during both disease stages. CNS-infiltrating cells stimulated with MOG produced similar amounts of IFN- γ but, IL-17 was produced only at the acute phase of EAE. The percentage of Foxp3+ Treg cells, at the spleen and CNS, was elevated during both phases. The degree of inflammation was similar at both disease stages. Partial clinical recovery observed during chronic EAE was associated with no IL-17 production and presence of Foxp3+ Treg cells in the CNS.
Assuntos
Sistema Nervoso Central/metabolismo , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/metabolismo , Regulação da Expressão Gênica , Interleucina-17/metabolismo , Animais , Feminino , Fatores de Transcrição Forkhead/metabolismo , Adjuvante de Freund , Inflamação , Interferon gama/metabolismo , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Esclerose Múltipla/imunologia , Baço/citologia , Células Th1/citologia , Células Th17/citologiaAssuntos
Suplementos Nutricionais , Vitamina D/farmacologia , Animais , Cálcio/sangue , Citocinas/metabolismo , Células Dendríticas/efeitos dos fármacos , Feminino , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Especificidade da Espécie , Linfócitos T Reguladores/efeitos dos fármacosRESUMO
Cellular immunity is critical for protection against tuberculosis, but its integrity is compromised during undernutrition. The present study was designed to evaluate if the attenuated mycobacterium BCG is a safe vaccine for undernourished individuals. An experimental model of undernutrition was established by subjecting BALB/c mice to dietary restriction. These animals received 70% of the amount of food consumed by the healthy control group and exhibited physiological alterations compatible with malnutrition, including body weight loss, reduced levels of triglycerides and glucose, and reduced lymphocyte numbers. Undernourished mice were immunized with BCG, and the mycobacterial loads in lymph nodes, spleen, liver, lungs, and thymus were determined. A much higher proportion of undernourished mice exhibited bacterial dissemination to the lymph nodes, spleen and liver. In addition, only undernourished animals had bacteria in the lungs and thymus. Concomitant with higher mycobacterial loads and more widespread BCG dissemination in undernourished mice, production of TNF-α, IFN-γ, and IL-10 was also diminished in these mice. Taken together, these results indicate that BCG infection is more severe in undernourished mice. Whether a similar phenomenon exists in undernourished children or not remains to be thoroughly investigated.
Assuntos
Vacina BCG/administração & dosagem , Desnutrição/imunologia , Tuberculose/imunologia , Animais , Vacina BCG/efeitos adversos , Carga Bacteriana , Citocinas/metabolismo , Modelos Animais de Doenças , Comportamento Alimentar , Humanos , Desnutrição/complicações , Camundongos , Camundongos Endogâmicos BALB C , Tuberculose/complicações , VacinaçãoRESUMO
GATA-binding factor 1 (GATA1) is a transcription factor that governs the development and function of multiple hematopoietic cell lineages. GATA1 is expressed in hematopoietic stem and progenitor cells (HSPCs) and is essential for erythroid lineage commitment; however, whether it plays a role in hematopoietic stem cell (HSC) biology and the development of myeloid cells, and what that role might be, remains unclear. We initially set out to test the role of eosinophils in experimental autoimmune encephalomyelitis (EAE), a model of central nervous system autoimmunity, using mice lacking a double GATA-site (ΔdblGATA), which lacks eosinophils due to the deletion of the dblGATA enhancer to Gata1, which alters its expression. ΔdblGATA mice were resistant to EAE, but not because of a lack of eosinophils, suggesting that these mice have an additional defect. ΔdblGATA mice with EAE had fewer inflammatory myeloid cells than the control mice, suggesting that resistance to EAE is caused by a defect in myeloid cells. Naïve ΔdblGATA mice also showed reduced frequency of CD11b+ myeloid cells in the blood, indicating a defect in myeloid cell production. Examination of HSPCs revealed fewer HSCs and myeloid cell progenitors in the ΔdblGATA bone marrow (BM), and competitive BM chimera experiments showed a reduced capacity of the ΔdblGATA BM to reconstitute immune cells, suggesting that reduced numbers of ΔdblGATA HSPCs cause a functional deficit during inflammation. Taken together, our data show that GATA1 regulates the number of HSPCs and that reduced GATA1 expression due to dblGATA deletion results in a diminished immune response following the inflammatory challenge.
Assuntos
Fator de Transcrição GATA1 , Células-Tronco Hematopoéticas , Doenças Neuroinflamatórias , Animais , Camundongos , Diferenciação Celular , Regulação da Expressão Gênica , Células-Tronco Hematopoéticas/metabolismo , Fator de Transcrição GATA1/metabolismoRESUMO
Candidiasis may affect the central nervous system (CNS), and although Candida albicans is predominant, non-albicans Candida species can also be associated with CNS infections. Some studies have suggested that Candida infections could increase the odds of multiple sclerosis (MS) development. In this context, we investigated whether systemic infection by non-albicans Candida species would affect, clinically or immunologically, the severity of experimental autoimmune encephalomyelitis (EAE), which is an animal model used to study MS. For this, a strain of C. glabrata, C. krusei, and C. parapsilosis was selected and characterized using different in vitro and in vivo models. In these analysis, all the strains exhibited the ability to form biofilms, produce proteolytic enzymes, and cause systemic infections in Galleria mellonella, with C. glabrata being the most virulent species. Next, C57BL/6 mice were infected with strains of C. glabrata, C. krusei, or C. parapsilosis, and 3 days later were immunized with myelin oligodendrocyte glycoprotein to develop EAE. Mice from EAE groups previously infected with C. glabrata and C. krusei developed more severe and more prevalent paralysis, while mice from the EAE group infected with C. parapsilosis developed a disease comparable to non-infected EAE mice. Disease aggravation by C. glabrata and C. krusei strains was concomitant to increased IL-17 and IFN-γ production by splenic cells stimulated with fungi-derived antigens and with increased percentage of T lymphocytes and myeloid cells in the CNS. Analysis of interaction with BV-2 microglial cell line also revealed differences among these strains, in which C. krusei was the strongest activator of microglia concerning the expression of MHC II and CD40 and pro-inflammatory cytokine production. Altogether, these results indicated that the three non-albicans Candida strains were similarly able to reach the CNS but distinct in terms of their effect over EAE development. Whereas C. glabrata and C. Krusei aggravated the development of EAE, C. parapsilosis did not affect its severity. Disease worsening was partially associated to virulence factors in C. glabrata and to a strong activation of microglia in C. krusei infection. In conclusion, systemic infections by non-albicans Candida strains exerted influence on the experimental autoimmune encephalomyelitis in both immunological and clinical aspects, emphasizing their possible relevance in MS development.
RESUMO
Myocardial infarction has a high mortality rate worldwide. Therefore, clinical intervention in cardiac remodeling after myocardial infarction is essential. Açai pulp is a natural product and has been considered a functional food because of its antioxidant/anti-inflammatory properties. The aim of the present study was to analyze the effect of açai pulp supplementation on cardiac remodeling after myocardial infarction in rats. After 7 days of surgery, male Wistar rats were assigned to six groups: sham animals fed standard chow (SA0, n = 14), fed standard chow with 2% açai pulp (SA2, n = 12) and fed standard chow with 5% açai pulp (SA5, n = 14), infarcted animals fed standard chow (IA0, n = 12), fed standard chow with 2% açai pulp (IA2, n = 12), and fed standard chow with 5% açai pulp (IA5, n = 12). After 3 months of supplementation, echocardiography and euthanasia were performed. Açai pulp supplementation, after myocardial infarction, improved energy metabolism, attenuated oxidative stress (lower concentration of malondialdehyde, P = 0.023; dose-dependent effect), modulated the inflammatory process (lower concentration of interleukin-10, P<0.001; dose-dependent effect) and decreased the deposit of collagen (lower percentage of interstitial collagen fraction, P<0.001; dose-dependent effect). In conclusion, açai pulp supplementation attenuated cardiac remodeling after myocardial infarction in rats. Also, different doses of açai pulp supplementation have dose-dependent effects on cardiac remodeling.
Assuntos
Euterpe , Infarto do Miocárdio , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Suplementos Nutricionais , Masculino , Infarto do Miocárdio/tratamento farmacológico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Ratos , Ratos Wistar , Remodelação VentricularRESUMO
Strongyloides venezuelensis is a parasitic nematode that has been used as a model to study human and animal strongyloidiasis. In this study, we compared the sensitivity between traditional methodologies and PCR assay to characterize the dynamics of S. venezuelensis infection and its migration route in Lewis rats subcutaneously infected with 4000 L3. The dynamics of the infection was determined by counting the number of eggs and by detecting parasite deoxyribonucleic acid in faeces samples. Both techniques similarly detected the infection at day 6 after larvae inoculation. However, PCR performed with the genus primer showed higher sensitivity during the recovery phase. Histological analysis and PCR assay were then used to follow parasite tissue migration. S. venezuelensis migration route included the muscular fibers below the skin, the pulmonary alveoli and the small intestine vilosities. The sensitivity of these two techniques to detect parasite's presence in these tissues was statistically similar.
Assuntos
Strongyloides/fisiologia , Estrongiloidíase/parasitologia , Animais , Encéfalo/parasitologia , DNA de Helmintos/análise , Fezes/parasitologia , Feminino , Intestino Delgado/parasitologia , Pulmão/parasitologia , Masculino , Músculo Esquelético/parasitologia , Contagem de Ovos de Parasitas , Reação em Cadeia da Polimerase , Ratos , Ratos Endogâmicos Lew , Sensibilidade e Especificidade , Pele/parasitologia , Strongyloides/genética , Strongyloides/isolamento & purificação , Fatores de Tempo , Vísceras/parasitologiaRESUMO
Peptides are molecules that have emerged as crucial candidates for the development of anticancer drugs. Spider venoms are a rich source of peptides (venom peptides - VPs) with biological effects. VPs have been tested as adjuvants in the activation of cells of the immune system with the aim of improving immunotherapies for the treatment of neoplasms. In the present study, the effects of SNX-482, a peptide from the African tarantula Hysterocrates gigas, on macrophages were described. The results showed that the peptide activated M0-macrophages, increasing costimulatory molecules (CD40, CD68, CD80, CD83, CD86) involved in antigen presentation, and also augmenting the checkpoint molecules PD-L1, CTLA-4 and FAS-L; these effects were not concentration-dependent. SNX-482 also increased the release of IL-23 and upregulated the expression of ccr4, ifn-g, gzmb and pdcd1, genes important for the anticancer response. The pretreatment of macrophages with the peptide did not interfere in the modulation of T cells, and macrophages previously polarized to M1 and M2 profile did not respond to SNX-482. These findings represent the expansion of knowledge about the use of VPs in drug discovery, pointing to a potential new candidate for anticancer immunotherapy. Considering that most immunotherapies target the adaptive system, the modulation of macrophages (an innate immune cell) by SNX-482 is especially relevant.
Assuntos
Adjuvantes Imunológicos/farmacologia , Ativação de Macrófagos/efeitos dos fármacos , Venenos de Aranha/química , Aranhas/química , Animais , Antígenos CD/imunologia , Linhagem Celular Tumoral , Polaridade Celular , Citocinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Expressão Gênica , Ativação de Macrófagos/imunologia , Camundongos , Neoplasias/genética , Neoplasias/imunologia , Venenos de Aranha/farmacologiaRESUMO
BACKGROUND: A DNA vaccine (pVAXhsp65) containing the gene of a heat-shock protein (hsp65) from Mycobacterium leprae showed high immunogenicity and protective efficacy against tuberculosis in BALB/c mice. A possible deleterious effect related to autoimmunity needed to be tested because hsp65 is highly homologous to the correspondent mammalian protein. In this investigation we tested the effect of a previous immunization with DNAhsp65 in the development of experimental autoimmune encephalomyelitis (EAE), a rat model of multiple sclerosis. METHODS: Female Lewis rats were immunized with 3 pVAXhsp65 doses by intramuscular route. Fifteen days after the last DNA dose the animals were evaluated for specific immunity or submitted to induction of EAE. Animals were evaluated daily for weight loss and clinical score, and euthanized during the recovery phase to assess the immune response and inflammatory infiltration at the central nervous system. RESULTS: Immunization with pVAXhsp65 induced a specific immune response characterized by production of IgG(2b) anti-hsp65 antibodies and IFN-gamma secretion. Previous immunization with pVAXhsp65 did not change EAE clinical manifestations (weight and clinical score). However, the vaccine clearly decreased brain and lumbar spinal cord inflammation. In addition, it downmodulated IFN-gamma and IL-10 production by peripheral lymphoid organs. CONCLUSION: Our data demonstrated that this vaccine does not trigger a deleterious effect on EAE development and also points to a potential protective effect.
Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/prevenção & controle , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Anticorpos Antibacterianos/biossíntese , Proteínas de Bactérias/imunologia , Chaperonina 60/imunologia , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/metabolismo , Feminino , Imunoglobulina G/biossíntese , Inflamação/imunologia , Inflamação/metabolismo , Inflamação/prevenção & controle , Ratos , Ratos Endogâmicos Lew , Vacinas de DNA/administração & dosagem , Vacinas de DNA/imunologiaRESUMO
More sensitive methodologies are necessary to improve strongyloidiasis diagnosis. This study compared the sensitivities of the McMaster modified technique and polymerase chain reaction (PCR) assays, both performed in faecal samples. Lewis rats were subcutaneously infected with 4,000, 400 or 40 infective third-stage larvae, considered as high, moderate or low infection, respectively. Seven days later, they were euthanized to count adult nematodes recovered from the small intestine. Stool samples were used to count the number of eggs per gram (EPG) of faeces and to detect parasite DNA by PCR performed with a species and a genus primer pair. The sensitivity of these assays depended upon parasite burden and the primer specificity. All assays presented 100% sensitivity at the highest parasite load. In the moderate infection, EPG and PCR with the genus primer maintained 100% specificity, whereas PCR sensitivity with the species primer decreased to 77.7%. In low infection, the sensitivity was 60% for EPG, 0% for PCR with the species primer and 90% for PCR done with the genus primer. Together, these results suggest that PCR with a genus primer can be a very sensitive methodology to detect Strongyloides venezuelensisin faeces of Lewis rats infected with very low parasite burden.
Assuntos
Fezes/parasitologia , Contagem de Ovos de Parasitas , Reação em Cadeia da Polimerase , Strongyloides , Estrongiloidíase/diagnóstico , Animais , DNA de Helmintos/análise , Feminino , Genótipo , Masculino , Ratos , Ratos Endogâmicos Lew , Sensibilidade e Especificidade , Strongyloides/genética , Strongyloides/isolamento & purificaçãoRESUMO
Multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE) are neuroinflammatory diseases of the central nervous system (CNS), where leukocytes and CNS resident cells play important roles in disease development and pathogenesis. The antimalarial drug chloroquine (CQ) has been shown to suppress EAE by modulating dendritic cells (DCs) and Th17 cells. However, the mechanism of action by which CQ modulates EAE is far from being elucidated. Here, we comprehensively analyzed the CNS of CQ and PBS-treated EAE mice to identify and characterize the cells that are affected by CQ. Our results show that leukocytes are largely modulated by CQ and have a reduction in the expression of inflammatory markers. Intriguingly, CQ vastly modulated the CNS resident cells astrocytes, oligodendrocytes (OLs) and microglia (MG), with the latter producing IL-10 and IL-12p70. Overall, our results show a panoramic view of the cellular components that are affect by CQ and provide further evidence that drug repurposing of CQ will be beneficial to MS patients.
RESUMO
Multiple sclerosis (MS) is a progressive disease of the central nervous system (CNS) that involves damage to the myelin sheath surrounding axons. MS therapy is based on immunomodulatory drugs that reduce disease recurrence and severity. Vitamin D is a hormone whose immunomodulatory ability has been widely demonstrated, including in experimental autoimmune encephalomyelitis (EAE), which is an animal model of CNS inflammation. In this study, we evaluated the potential of very early intervention with the active form of vitamin D (1,25-dihydroxyvitamin D3) to control neuroinflammation during EAE development. EAE was induced in C57BL/6J mice and 1,25-dihydroxyvitamin D3 administration began 1 day after disease induction. This procedure decreased prevalence, clinical score, inflammation, and demyelination. It also reduced MHCII expression in macrophages and microglia as well as the level of oxidative stress and messenger RNA (mRNA) expression for NLRP3, caspase-1, interleukin (IL)-1ß, CX3CR1, CCL17, RORc and Tbx21 at the CNS. Otherwise, mRNA expression for ZO-1 increased at the lumbar spinal cord. These effects were accompanied by the stabilization of blood-spinal cord barrier permeability. The results of this study indicate that early intervention with 1,25-dihydroxyvitamin D3 can control the neuroinflammatory process that is the hallmark of EAE and MS immunopathogenesis and should thus be explored as an adjunct therapy for MS patients.