Avaliação da atividade da isatina-3-N4-benziltiossemicarbazona (IBTC) como antioxidante na proteção da LDL contra a oxidação

Detalhes bibliográficos
Ano de defesa: 2012
Autor(a) principal: Barcelos, Rômulo Pillon
Orientador(a): Não Informado pela instituição
Banca de defesa: Não Informado pela instituição
Tipo de documento: Dissertação
Tipo de acesso: Acesso aberto
Idioma: por
Instituição de defesa: Universidade Federal de Santa Maria
BR
Bioquímica
UFSM
Programa de Pós-Graduação em Ciências Biológicas: Bioquímica Toxicológica
Programa de Pós-Graduação: Não Informado pela instituição
Departamento: Não Informado pela instituição
País: Não Informado pela instituição
Palavras-chave em Português:
LDL
Link de acesso: http://repositorio.ufsm.br/handle/1/11203
Resumo: Several lines of evidence support the hypotheses that the oxidation of low density lipoprotein (LDL) is a proatherogenic factor. Oxidative stress is one of the causes of the overproduction of reactive species that increase the formation of oxidized LDL. Thiosemicarbazones are compounds used in anticancer, antiviral and antifungal therapy; however, their redox activities have been controversial. Thus, we tested, in vitro, the possible antioxidant activity of a thiosemicarbazone derivate, the isatin-3-N4-benzilthiosemicarbazone (IBTC). We measured the conjugated diene formation in serum and LDL induced by two oxidant agents, 2,2-azobis(2-amidinopropane dihydrochloride) (AAPH) and Cu2+, as well as the loss of tryptophan fluorescence in LDL induced by Cu2+. The total reactive antioxidant potential (TRAP), Thiobarbituric acid reactive substances (TBARS) formation in human LDL and plasma and in different rat tissues was also assessed. The toxicity of IBTC was measured using aortic slices viability assay. The results show that IBTC reduced the formation of conjugated dienes AAPH and Cu2+- induced increased in a dose-dependent manner the lag phase. IBTC also prevented the tryptophan fluorescence loss, and reduced the TBARS formation in LDL, plasma and rat tissues, showing no toxicity to aortic slices. These data indicate that IBTC is a good antioxidant and a promising antiatherogenic agent for further studies in vivo.