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1.
Eur J Nutr ; 53(3): 779-92, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24061349

RESUMO

INTRODUCTION: Neutrophils provide the first line of defense of the innate immune system by phagocytosing, killing and digesting bacteria and fungi. During this process, neutrophils produce reactive oxygen species (ROS), which in excess, can damage the cells themselves and surrounding tissues. The carotenoid fucoxanthin (Fc) has been studied concerning its antioxidant and anti-inflammatory actions. Vitamin c (Vc) also demonstrates potent antioxidant action. This study aimed to evaluate the effect of Fc (2 µM) in association with Vc (100 µM) on functional parameters of human neutrophils in vitro. MATERIALS AND METHODS: We evaluated the migration and phagocytic capacity, intracellular calcium mobilization, ROS production (O2(·)⁻, H2O2, HOCl), myeloperoxidase activity, profile of antioxidant enzymes, phosphorylation of p38 MAPK and p65 NFκB subunit, GSH/GSSG ratio and release of pro-inflammatory cytokines (TNF-α and IL-6) in neutrophils under different stimuli. RESULTS: We verified an increase in phagocytic capacity for all treatments, together with an increase in intracellular calcium only in cells treated with Fc and Fc + Vc. ROS production was reduced by all treatments, although Vc was a better antioxidant than Fc. Phosphorylation of the p-65 subunit of NFκB was reduced in cells treated with Fc + Vc and release of TNF-α and IL-6 was reduced by all treatments. These findings indicate that the regulation of inflammatory cytokines by neutrophils is not exclusively under the control of the NFκB pathway. Fc reduced the activity of some antioxidant enzymes, whereas Vc increased GR activity and the GSH/GSSG ratio. CONCLUSION: In conclusion, the results presented in this study clearly show an immunomodulatory effect of the carotenoid fc alone or in combination with Vc on the function of human neutrophils.


Assuntos
Anti-Inflamatórios não Esteroides/metabolismo , Antioxidantes/metabolismo , Ácido Ascórbico/metabolismo , Ativação de Neutrófilo , Neutrófilos/imunologia , Fagocitose , Xantofilas/metabolismo , Adulto , Sinalização do Cálcio , Movimento Celular , Células Cultivadas , Suplementos Nutricionais , Feminino , Humanos , Masculino , Neutrófilos/citologia , Neutrófilos/metabolismo , Fosforilação , Processamento de Proteína Pós-Traducional , Espécies Reativas de Oxigênio/metabolismo , Fator de Transcrição RelA/metabolismo , Adulto Jovem
2.
Int Immunopharmacol ; 14(4): 690-7, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23085288

RESUMO

During normal B- and T-cell life, processes including activation, proliferation, signaling pathways and apoptosis are markedly dependent on ROS generation. However, these cells can also suffer the effect of oxidant overproduction. Thus, the purpose of the present study was to examine the possible pro-oxidant effects of MGO/high glucose and antioxidant effects of astaxanthin associated with vitamin C on some oxidative and antioxidant parameters of human lymphocytes in vitro. Lymphocytes from healthy subjects were treated with 20mM of glucose and 30 µM MGO followed or not by the addition of the antioxidants astaxanthin (2 µM) and vitamin C (100 µM) for up to 24h. We examined superoxide dismutase (SOD), catalase, glutathione peroxidase, glutathione reductase, and glucose-6-phosphate dehydrogenase (G6PDH) activities, GSH/GSSG ratio and total thiol and carbonyl content. Oxidative parameters included superoxide anion, hydrogen peroxide and nitric oxide production. The association of astaxanthin and vitamin C proved to be a powerful antioxidant in human lymphocytes as showed by the marked reduction in superoxide anion, and hydrogen peroxide production as well as increased GSH content, GSH/GSSG ratio, GPx and GR activities. The antioxidant association showed to be more potent than their individual application. High glucose and methylglyoxal did not promote oxidative stress in human lymphocytes, since neither the oxidative parameters nor the antioxidant defense system was altered. According to these results, new therapies with the association of astaxanthin and vitamin C may be helpful to improve the immune function of patients with exacerbated production of ROS.


Assuntos
Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Glucose/farmacologia , Linfócitos/efeitos dos fármacos , Adolescente , Adulto , Antioxidantes/metabolismo , Células Cultivadas , Relação Dose-Resposta a Droga , Feminino , Glucose/administração & dosagem , Humanos , Linfócitos/metabolismo , Masculino , Estresse Oxidativo , Espécies Reativas de Nitrogênio , Espécies Reativas de Oxigênio , Xantofilas/farmacologia , Adulto Jovem
3.
Toxicol In Vitro ; 26(7): 1181-90, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22750055

RESUMO

The purpose of the present study was to find out whether co-treatment of human neutrophils with high glucose and methylglyoxal (MGO) can alter the biochemical parameters of human neutrophils. We also examined if astaxanthin associated with vitamin C can improve those biochemical parameters. Neutrophils from healthy subjects were treated with 20mM of glucose and 30 µM MGO followed or not by the addition of the antioxidants astaxanthin (2 µM) and vitamin C (100 µM). MGO/high glucose treatment reduced the phagocytic capacity and the G6PDH, total/SOD and GR activities. Additionally, there was an increase in the activity of myeloperoxidase (MPO) with consequent increase in the hypochlorous acid production, CAT activity and in the release of IL-6 cytokine without changes in intracellular calcium mobilization. Our study also shows that the association of astaxanthin with vitamin C greatly improved neutrophil phagocytic capacity, decreasing all reactive oxygen species measured, pro-inflammatory IL-1ß and TNF-α release, MPO activity and HClO production. The combination of astaxanthin with vitamin C alone has more antioxidant and anti-inflammatory effects than when they were in the presence of MGO/high glucose. Injury to the function of neutrophils due to high glucose and methylglyoxal appears not to involve oxidative stress or calcium release. The association of antioxidants astaxanthin and vitamin C promoted a significant improvement in the function of neutrophils and in the redox status.


Assuntos
Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Fibrinolíticos/farmacologia , Neutrófilos/efeitos dos fármacos , Catalase/metabolismo , Membrana Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Combinação de Medicamentos , Feminino , Glucose/farmacologia , Glucosefosfato Desidrogenase/metabolismo , Humanos , Interleucina-6/metabolismo , Masculino , Neutrófilos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Peroxidase/metabolismo , Fagocitose/efeitos dos fármacos , Carbonilação Proteica/efeitos dos fármacos , Aldeído Pirúvico/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Xantofilas/farmacologia , Adulto Jovem
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