Inhibitory activity of liposomal flavonoids during oxidative metabolism of human neutrophils upon stimulation with immune complexes and phorbol ester

Autor(es)

Landi-Librandi, Ana Paula ^[1] ; Caleiro Seixas Azzolini, Ana Elisa ^[1] ; de Oliveira, Carlos Alberto ^[2] ; Lucisano-Valim, Yara Maria ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Fac Ciencias Farmaceut Ribeirao Preto, Dept Fis & Quim, BR-14040903 Ribeirao Preto, SP - Brazil

^[2] Univ Fed Uberlandia, Ctr Ciencias Exatas & Tecnol, Inst Quim, BR-38400 Uberlandia, MG - Brazil

• Tipo de documento: Artigo Científico
• Fonte: DRUG DELIVERY; v. 19, n. 4, p. 177-187, MAY 2012.
• Citações Web of Science: 16

Resumo

Context and objective: The massive production of reactive oxygen species by neutrophils during inflammation may cause damage to tissues. Flavonoids act as antioxidants and have anti-inflammatory effects. In this study, liposomes loaded with these compounds were evaluated as potential antioxidant carriers, in attempt to overcome their poor solubility and stability. Materials and methods: Liposomes containing quercetin, myricetin, kaempferol or galangin were prepared by the ethanol injection method and analyzed as inhibitors of immune complex (IC) and phorbol ester-stimulated neutrophil oxidative metabolism by luminol (CLlum) and lucigenin-enhanced (CLluc) chemiluminescence (CL) assays. The mechanisms involved this activity of liposomal flavonoids, such as cytotoxicity and superoxide anion scavenging capacity, and their effect on phagocytosis of ICs were also investigated. Results and discussion: The results showed that the inhibitory effect of liposomal flavonoids on CLlum and CLluc is inversely related to the number of hydroxyl groups in the flavonoid B ring. Moreover, phagocytosis of liposomes by neutrophils does not seem to necessarily promote such activity, as the liposomal flavonoids are also able to reduce CL when the cells are pretreated with cytochalasin B. Under assessed conditions, the antioxidant liposomes are not toxic to the human neutrophils and do not interfere with IC-induced phagocytosis. Conclusion: The studied liposomes can be suitable carriers of flavonoids and be an alternative for the treatment of diseases in which a massive oxidative metabolism of neutrophils is involved. (AU)

• Processo FAPESP: 07/00161-3 - Estudo do efeito da composição de lipossomas contendo flavonóides na ativação do sistema complemento e no metabolismo oxidativo de neutrófilos humanos: implicações na estabilidade e aplicação deste sistema de liberação na terapia de doenças inflamatórias
• Beneficiário: Yara Maria Lucisano Valim
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 06/04398-5 - Estudo in vitro do efeito da ativação do Sistema Complemento na estabilidade de lipossomas de diferentes composições contendo flavonóides: seleção do sistema de liberação mais estável e avaliação da sua aplicabilidade na terapia de doenças inflamatórias.
• Beneficiário: Ana Paula Landi Librandi
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado