RESUMO
Neospora caninum infection is an important cause of neuromuscular disease in dogs and abortion in cattle, leading to significant economic losses in beef and dairy industries. The protective immunity against apicomplexan parasites, specifically Toxoplasma gondii and N. caninum, is typically achieved by inducing an IL-12-driven Th1 immune response. IL-12 stimulates IFN-γ production, which activates Inducible Nitric Oxide Synthase (iNOS) and promotes consequent Nitric Oxide (NO) synthesis, classically described as one of the main effector mechanisms for parasite elimination. Here, we aimed to evaluate the role played by iNOS during N. caninum infection. Our results show that N. caninum infection in C57BL/6 wild type (WT) mice induce NO production in vivo and in vitro. In agreement, iNOS deficient mice, as well as WT mice treated with iNOS inhibitor aminoguanidine, succumbed during acute infection with a dose lethal to 50 % of the WT mice, and presented significant increase in parasite load when submitted to sub-lethal infection protocols. Interestingly, the lack of control of parasite proliferation observed in iNOS-/- mice was associated with notable CNS inflammation and increased production of the main systemic proinflammatory cytokines (IL-12, IFN-γ, IL-6, TNF and IL-17A). Taken together, our findings show that iNOS plays an important role in restricting N. caninum replication, while also modulates the inflammatory process induced by the infection.
Assuntos
Coccidiose/enzimologia , Neospora/imunologia , Óxido Nítrico Sintase Tipo II/fisiologia , Animais , Coccidiose/parasitologia , Coccidiose/patologia , Interferon gama/análise , Subunidade p40 da Interleucina-12/análise , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/deficiênciaRESUMO
BACKGROUND: In the present study, we examined the inhibitory effects of a methanolic extract, dichloromethane fraction, water layer, and polyhydroxylated sterols (1-4) isolated from the Vietnamese starfish Protoreaster nodosus on pro-inflammatory cytokine (IL-12 p40, IL-6, and TNF-α) production in LPS-stimulated bone marrow-derived dendritic cells (BMDCs) using enzyme-linked immunosorbent assays (ELISA). RESULTS: The methanolic extract and dichloromethane fraction exerted potent inhibitory effects on the production of all three pro-inflammatory cytokines, with IC50 values ranging from 0.60 ± 0.01 to 26.19 ± 0.64 µg/mL. Four highly pure steroid derivatives (1-4) were isolated from the dichloromethane fraction and water layer of P. nodosus. Potent inhibitory activities were also observed for (25S) 5α-cholestane-3ß,4ß,6α,7α,8ß,15α,16ß,26-octol (3) on the production of IL-12 p40 and IL-6 (IC50s = 3.11 ± 0.08 and 1.35 ± 0.03 µM), and for (25S) 5α-cholestane-3ß,6α,8ß,15α,16ß,26-hexol (1) and (25S) 5α-cholestane-3ß,6α,7α,8ß,15α,16ß,26-heptol (2) on the production of IL-12 p40 (IC50s = 0.01 ± 0.00 and 1.02 ± 0.01 µM). Moreover, nodososide (4) exhibited moderate inhibitory effects on IL-12 p40 and IL-6 production. CONCLUSION: This is the first report of the anti-inflammatory activity from the starfish P. nodosus. The main finding of this study is the identification oxygenated steroid derivatives from P. nodosus with potent anti-inflammatory activities that may be developed as therapeutic agents for inflammatory diseases.
Assuntos
Anti-Inflamatórios/análise , Células Dendríticas/efeitos dos fármacos , Subunidade p40 da Interleucina-12/farmacologia , Interleucina-6/farmacologia , Estrelas-do-Mar/química , Fator de Necrose Tumoral alfa/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Concentração Inibidora 50 , Subunidade p40 da Interleucina-12/análise , Interleucina-6/análise , Lipopolissacarídeos , Camundongos Endogâmicos C57BL , Cultura Primária de Células , Esteroides/administração & dosagem , Fator de Necrose Tumoral alfa/análise , VietnãRESUMO
BACKGROUND: In the present study, we examined the inhibitory effects of a methanolic extract, dichloromethane fraction, water layer, and polyhydroxylated sterols (1-4) isolated from the Vietnamese starfish Protoreaster nodosus on pro-inflammatory cytokine (IL-12 p40, IL-6, and TNF-α) production in LPS-stimulated bone marrow-derived dendritic cells (BMDCs) using enzyme-linked immunosorbent assays (ELISA). RESULTS: The methanolic extract and dichloromethane fraction exerted potent inhibitory effects on the production of all three pro-inflammatory cytokines, with IC50 values ranging from 0.60 ± 0.01 to 26.19 ± 0.64 µg/mL. Four highly pure steroid derivatives (1-4) were isolated from the dichloromethane fraction and water layer of P. nodosus. Potent inhibitory activities were also observed for (25S)5α-cholestane-3ß,4ß,6α,7α,8ß,15α,16ß,26-octol (3) on the production of IL-12 p40 and IL-6 (IC50s = 3.11 ± 0.08 and 1.35 ± 0.03 µM), and for (25S) 5α-cholestane-3ß,6α,8ß,15α,16ß,26-hexol (1) and (25S)5α-cholestane-3ß,6α,7α,8ß,15α,16ß,26-heptol (2) on the production of IL-12 p40 (IC50s = 0.01 ± 0.00 and and 1.02 ± 0.01 µM). Moreover, nodososide (4) exhibited moderate inhibitory effects on IL-12 p40 and IL-6 production. CONCLUSION: This is the first report of the anti-inflammatory activity from the starfish P. nodosus. The main finding of this study is the identification oxygenated steroid derivatives from P. nodosus with potent anti-inflammatory activities that may be developed as therapeutic agents for inflammatory diseases.
Assuntos
Animais , Camundongos , Estrelas-do-Mar/química , Células Dendríticas/efeitos dos fármacos , Interleucina-6/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Subunidade p40 da Interleucina-12/farmacologia , Anti-Inflamatórios/análise , Esteroides/administração & dosagem , Vietnã , Ensaio de Imunoadsorção Enzimática , Sobrevivência Celular/efeitos dos fármacos , Lipopolissacarídeos , Interleucina-6/análise , Fator de Necrose Tumoral alfa/análise , Concentração Inibidora 50 , Subunidade p40 da Interleucina-12/análise , Cultura Primária de Células , Camundongos Endogâmicos C57BLRESUMO
In recent years, better diagnostics for tuberculosis (TB) has received increasing attention, especially the diagnosis of tuberculous pleural effusion, which is difficult and at present the main tool in TPE diagnostic is pleural effusion smear and culture, but unfortunately, sensitivities are low, therefore better TPE diagnostic tools are needed. The aim of this study was to find a diagnostic algorithm to assess the progress in TPE diagnostic at the Hospital Vargas de Caracas, that permits identification of the majority of patients, at a satisfactory cost-benefit ratio, evaluating the levels of IFN-gamma and IL-12p40 in pleural effusion and serum, as well as the antibody reactivity in order to compare it with microbiological tests. A total of 60 individuals with pleural effusion were studied; 20 patients with tuberculous pleural effusion (TPE) formed the patient group and 40 patients with non-tuberculous pleural effusion (NTPE) formed the control group. The levels of IFN-gamma and IL-12p40 in effusion and serum and class and subclasses of IgG reactivity to Mycobacterium tuberculosis antigens were measured by ELISA. The utility of these methods for diagnosis of TPE was evaluated using receiver operating characteristic (ROC) curve analysis. The results of the 11 immunological methods evaluated showed that the anti-PPD IgG2 method was able to reach the highest specificity of 95% (CI: 88.3-101.8), positive predictive value (PPV) = 75 (at 30% sensitivity); while that the overall sensitivity of methods was between 95% and 30%, of these, two methods reached higher sensitivities; increased levels of pleural IFN-gamma, with a sensitivity of 95% (CI: 85.5-104.5) with the highest negative predictive value (NPV) = 97, (at 82.5% specificity), followed by decreased levels of serum IL-12p40 with a sensitivity of 95% (CI: 85.5-104.5), NPV = 95.2 (at 50% specificity). In contrast, microbiological methods showed that smear had a sensitivity of only 20%, while smear plus culture had, a sensitivity of 70%. Considering that TPE represents approximately 15 percent of all the TB clinically diagnosed at the Hospital Vargas de Caracas, in those patients with preliminary microbiology negativity in the effusion, the combined analysis of pleural IFN-gamma and anti-PPD IgG2 could represent a fast and effective diagnostic algorithm for improving the diagnosis previous to obtain culture results. In this way treatment against TB could be initiated or the need to cytological and pleural biopsy could be considered.
Assuntos
Técnicas Imunológicas , Interferon gama/análise , Subunidade p40 da Interleucina-12/análise , Derrame Pleural/diagnóstico , Tuberculose Pleural/diagnóstico , Adolescente , Adulto , Idoso , Algoritmos , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Análise Custo-Benefício , Estudos Transversais , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/classificação , Imunoglobulina G/imunologia , Técnicas Imunológicas/economia , Interferon gama/sangue , Subunidade p40 da Interleucina-12/sangue , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/imunologia , Derrame Pleural/imunologia , Derrame Pleural/metabolismo , Valor Preditivo dos Testes , Curva ROC , Sensibilidade e Especificidade , Tuberculose Pleural/imunologia , Tuberculose Pleural/metabolismo , Venezuela , Adulto JovemRESUMO
AIM: Capsular polysaccharides play an important role in the virulence of Gram-positive and Gram-negative bacteria. In Porphyromonas gingivalis, six serotypes have been described based on capsular antigenicity and its pathogenicity has been correlated both in vitro and in animal models. This study aimed to investigate the differential response of human dendritic cells (DCs) when stimulated with different P. gingivalis capsular serotypes. MATERIALS AND METHODS: Using different multiplicity of infection (MOI) of the encapsulated strains K1-K6 and the non-encapsulated K(-) strain of P. gingivalis, the mRNA expression levels for interleukin (IL)-1beta, IL-2, IL-5, IL-6, IL-10, IL-12, IL-13, interferon (IFN)-gamma, tumour necrosis factor (TNF)-alpha, and TNF-beta in stimulated DCs were quantified by real-time reverse transcription-polymerase chain reaction. RESULTS: All P. gingivalis capsular serotypes induced a T-helper type 1 (Th1) pattern of cytokine expression. K1- and K2-stimulated DCs expressed higher levels of IL-1beta, IL-6, IL-12p35, IL-12p40, and IFN-gamma and at lower MOI than DCs stimulated with the other strains. CONCLUSIONS: These results demonstrate a differential potential of P. gingivalis capsular serotypes to induce DC responses and a higher capacity of strains K1 W83 and K2 HG184 than other K serotypes to trigger cytokine expression.