RESUMO
Pseudobrickellia brasiliensis (Asteraceae) is a plant commonly known as arnica-do-campo and belongs to the native flora of the Brazilian Cerrado. The alcoholic extract of the plant has been used as an anti-inflammatory agent in folk medicine, but the biological mechanism of action has not been elucidated. The present study evaluated the composition of P. brasiliensis aqueous extract and its effects on pro-inflammatory cytokine production and lymphocyte proliferation. The extracts were prepared by sequential maceration of P. brasiliensis leaves in ethanol, ethyl acetate, and water. Extract cytotoxicity was evaluated by trypan blue exclusion assay, and apoptosis and necrosis were measured by staining with annexin V-FITC and propidium iodide. The ethanolic (ETA) and acetate (ACE) extracts showed cytotoxic effects. The aqueous extract (AQU) was not cytotoxic. Peripheral blood mononuclear cells stimulated with phorbol myristate acetate and ionomycin and treated with AQU (100 μg/mL) showed reduced interferon (IFN)-γ and tumor necrosis factor (TNF)-α expression. AQU also inhibited lymphocyte proliferative response after nonspecific stimulation with phytohemagglutinin. The aqueous extract was analyzed by liquid chromatography coupled with photodiode array detection and mass spectrometry. Quinic acid and its derivatives 5-caffeoylquinic acid and 3,5-dicaffeoylquinic acid, as well as the flavonoids luteolin and luteolin dihexoside, were detected. All these compounds are known to exhibit anti-inflammatory activity. Taken together, these findings demonstrate that P. brasiliensis aqueous extract can inhibit the pro-inflammatory cytokine production and proliferative response of lymphocytes. These effects may be related to the presence of chemical substances with anti-inflammatory actions previously reported in scientific literature.
Assuntos
Humanos , Anti-Inflamatórios/farmacologia , Asteraceae/química , Proliferação de Células/efeitos dos fármacos , Interferon gama/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Fator de Necrose Tumoral alfa/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Interferon gama/metabolismo , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Extratos Vegetais/química , Fatores de Tempo , Fator de Necrose Tumoral alfa/metabolismoRESUMO
T-cell based vaccines against human immunodeficiency virus (HIV) generate specific responses that may limit both transmission and disease progression by controlling viral load. Broad, polyfunctional, and cytotoxic CD4+T-cell responses have been associated with control of simian immunodeficiency virus/HIV-1 replication, supporting the inclusion of CD4+ T-cell epitopes in vaccine formulations. Plasmid-encoded granulocyte-macrophage colony-stimulating factor (pGM-CSF) co-administration has been shown to induce potent CD4+ T-cell responses and to promote accelerated priming and increased migration of antigen-specific CD4+ T-cells. However, no study has shown whether co-immunisation with pGM-CSF enhances the number of vaccine-induced polyfunctional CD4+ T-cells. Our group has previously developed a DNA vaccine encoding conserved, multiple human leukocyte antigen (HLA)-DR binding HIV-1 subtype B peptides, which elicited broad, polyfunctional and long-lived CD4+ T-cell responses. Here, we show that pGM-CSF co-immunisation improved both magnitude and quality of vaccine-induced T-cell responses, particularly by increasing proliferating CD4+ T-cells that produce simultaneously interferon-γ, tumour necrosis factor-α and interleukin-2. Thus, we believe that the use of pGM-CSF may be helpful for vaccine strategies focused on the activation of anti-HIV CD4+ T-cell immunity.
Assuntos
Animais , Feminino , Humanos , Vacinas contra a AIDS/imunologia , Antígenos Virais/imunologia , /imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/administração & dosagem , HIV-1 , Imunidade Celular/imunologia , Vacinas de DNA/imunologia , Adjuvantes Imunológicos/administração & dosagem , /efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Movimento Celular/imunologia , Sequência Conservada/imunologia , ELISPOT , Citometria de Fluxo , Vetores Genéticos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Infecções por HIV/prevenção & controle , Antígenos HLA-DR/imunologia , Interferon gama/efeitos dos fármacos , Interferon gama/metabolismo , /metabolismo , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Camundongos Endogâmicos BALB C , Plasmídeos , Ligação Proteica/imunologia , Fator de Necrose Tumoral alfa/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Scutellaria baicalensis Georgi is one of the important medicinal herbs widely used for the treatment of various inflammatory diseases in Asia. Baicalin (BA) is a bioactive anti-inflammatory flavone found abundantly in Scutellaria baicalensis Georgi. To explore the therapeutic potential of BA, we examined the effects of systemic administration of the flavone (5 and 10 mg/kg, ip) on relapsing/remitting experimental autoimmune encephalomyelitis (EAE) induced by proteolipid protein 139-151 in SJL/J mice, an experimental model of multiple sclerosis. The mice treated with PBS or BA at day -1 and for 3 consecutive days were observed daily for clinical signs of disease up to 60 days after immunization. In the PBS-EAE group, neurological scores were: incidence (100 percent), mean day of onset (8.0 ± 0.73), peak clinical score (3.0 ± 0.4), and cumulative disease index (141.8 ± 19.4). In the BA-EAE group (5 or 10 mg kg-1 day-1, respectively), incidence (95 or 90 percent), mean day of onset (9.0 ± 0.80 or 9.2 ± 0.75; P = 0.000), peak clinical score (2.2 ± 0.3 or 2.0 ± 0.3; P = 0.000), and cumulative disease index (75.9 ± 10.1 or 62.9 ± 8.4; P = 0.000) decreased, accompanied by the histopathological findings (decrease of dense mononuclear infiltration surrounding vascellum) for the spinal cord. Additionally, the in vitro effects of BA (5, 10, and 25 µM) on mononuclear cells collected from popliteal and inguinal lymph nodes of day-10 EAE mice were evaluated using an MTT reduction assay for cell proliferation, and ELISA to measure IFN-g and IL-4 cytokines. Compared with the control group, BA caused an increase in IL-4 (EAE-DMSO: 3.56 ± 0.42 pg/mL vs EAE-BA (5, 10, and 25 µM): 6.03 ± 1.1, 7.83 ± 0.65, 10.54 ± 1.13 pg/mL, respectively; P < 0.001); but inhibited IFN-g (EAE-DMSO: 485.76 ± 25.13 pg/mL vs EAE-BA (5, 10, and 25 µM): 87.08 ± 9.24, 36.27 ± 5.44, 19.18 ± 2.93 pg/mL, respectively; P < 0.001) and the proliferation of mononuclear cells (EAE-DMSO:...
Assuntos
Animais , Feminino , Camundongos , Anti-Inflamatórios não Esteroides/uso terapêutico , Encefalomielite Autoimune Experimental/tratamento farmacológico , Flavonoides/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/patologia , Interferon gama/efeitos dos fármacos , Interferon gama/imunologia , /imunologia , Índice de Gravidade de Doença , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologiaRESUMO
Antecedentes: Es importante el uso con fines terapéuticos de inmunomoduladores que funcionen como inductores de la sintesis de interferón natural (IFN-n), principalmente si se considera el costo y toxicidad del interferón recombinante. En este trabajo, se estudia el efecto que la aplicación de uno de estos inductores, el ácido ribonucleico de transferencia (RNAt), tuvo sobre los niveles séricos del interferón gamma (IFN-ç) y del factor de necrosis tumoral alfa (TNF-Ó). Objetivos: Determinar la concentración del INF-ç y el TNF-Ó en el plasma de sujetos a quienes se les aplicó un RNAt de origen fúngico como inductor de la síntesis de IFN-n. Material y Métodos: A nueve voluntarios sanos se les administró por vía IM 200 mg del RNAt, y se valoró en plasma de sangre venosa antes y dos horas después de la apliación del RNAt, la concentración del IFN-ç y del TNF-Ó por la técnica de ELISA. Resultados: Se observó que los niveles de IFN-ç y del TNF-Ó se incrementaron de 267.83 ñ 208.03 a 2230 ñ 2088.73 pg/mL, y de 48.92 ñ 88.07 a 261.65 ñ 80.61 pg/mL respectivamante (Prom. ñ D.S, p < 0.05), a las dos horas de la administración de RNAt. Conclusión: Con la administración del RNAt se observa una tendencia de incremento en la concentración de IFN-ç y del TNF-Ó, en el plasma de sujetos normales