title: In vitro and in vivo determination of antioxidant activity and mode of action of isoquercitrin and Hyptis fasciculata.
abstract: Reactive oxygen species (ROS) are thought to underline the process of ageing and the pathogenicity of various diseases, such as neurodegenerative disorders and cancer. The use of traditional medicine is widespread and plants still present a large source of natural antioxidants that might serve as leads for the development of novel drugs. In this paper, the alcoholic extract from leaves of Hyptis fasciculata, a Brazilian medicinal plant, and isoquercitrin, a flavonoid identified in this species, showed to be active as 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavengers. The extract of Hyptis fasciculata and isoquercitrin were also able to increase tolerance of the eukaryotic microorganism Saccharomyces cerevisiae to both hydrogen peroxide and menadione, a source of superoxide. Cellular protection was correlated with a decrease in oxidative stress markers, such as levels of ROS, protein carbonylation and lipid peroxidation, confirming the antioxidant potential of Hyptis fasciculata and isoquercitrin.
authors.affiliation: Departamento de Bioquímica, Instituto de Química, UFRJ, Rio de Janeiro, Brazil. carmelita@iq.ufrj.br
authors.forename: C G
authors.initials: CG
authors.lastname: Silva
authors.forename: R J
authors.initials: RJ
authors.lastname: Raulino
authors.forename: D M
authors.initials: DM
authors.lastname: Cerqueira
authors.forename: S C
authors.initials: SC
authors.lastname: Mannarino
authors.forename: M D
authors.initials: MD
authors.lastname: Pereira
authors.forename: A D
authors.initials: AD
authors.lastname: Panek
authors.forename: J F M
authors.initials: JF
authors.lastname: Silva
authors.forename: F S
authors.initials: FS
authors.lastname: Menezes
authors.forename: E C A
authors.initials: EC
authors.lastname: Eleutherio
mesh_terms: D000975:Antioxidants / Q000494:pharmacology*; D001713:Biphenyl Compounds; D002478:Cells, Cultured; D020441:Ginkgo biloba / Q000737:chemistry; D006861:Hydrogen Peroxide / Q000494:pharmacology; D031331:Hyptis / Q000737:chemistry*; D015227:Lipid Peroxidation / Q000187:drug effects; D016877:Oxidants / Q000494:pharmacology; D010636:Phenols / Q000032:analysis / Q000494:pharmacology; D010851:Picrates; D035261:Plant Components, Aerial; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D010946:Plants, Medicinal / Q000737:chemistry; D050050:Protein Carbonylation / Q000187:drug effects; D011794:Quercetin / Q000031:analogs & derivatives* / Q000494:pharmacology; D012441:Saccharomyces cerevisiae / Q000187:drug effects; D024483:Vitamin K 3 / Q000494:pharmacology; D014815:Vitamins / Q000494:pharmacology
chemical_list: D000975:Antioxidants; D001713:Biphenyl Compounds; D016877:Oxidants; D010636:Phenols; D010851:Picrates; D010936:Plant Extracts; D014815:Vitamins; C016527:isoquercitrin; D024483:Vitamin K 3; D011794:Quercetin; D006861:Hydrogen Peroxide; C004931:1,1-diphenyl-2-picrylhydrazyl