title: Antioxidant properties of xanthones from Calophyllum brasiliense: prevention of oxidative damage induced by FeSO₄.
abstract: BACKGROUND
  Reactive oxygen species (ROS) are important mediators in a number of degenerative diseases. Oxidative stress refers to the imbalance between the production of ROS and the ability to scavenge these species through endogenous antioxidant systems. Since antioxidants can inhibit oxidative processes, it becomes relevant to describe natural compounds with antioxidant properties which may be designed as therapies to decrease oxidative damage and stimulate endogenous cytoprotective systems. The present study tested the protective effect of two xanthones isolated from the heartwood of Calophyllum brasilienses against FeSO₄-induced toxicity.
  
  
  METHODS
  Through combinatory chemistry assays, we evaluated the superoxide (O₂·⁻), hydroxyl radical (OH·), hydrogen peroxide (H₂O₂) and peroxynitrite (ONO⁻) scavenging capacity of jacareubin (xanthone III) and 2-(3,3-dimethylallyl)-1,3,5,6-tetrahydroxyxanthone (xanthone V). The effect of these xanthones on murine DNA and bovine serum albumin degradation induced by an OH· generator system was also evaluated. Additionally, we investigated the effect of these xanthones on ROS production, lipid peroxidation and glutathione reductase (GR) activity in FeSO₄-exposed brain, liver and lung rat homogenates.
  
  
  RESULTS
  Xanthone V exhibited a better scavenging capacity for O₂·⁻, ONOO⁻ and OH· than xanthone III, although both xanthones were unable to trap H₂O₂. Additionally, xanthones III and V prevented the albumin and DNA degradation induced by the OH· generator system. Lipid peroxidation and ROS production evoked by FeSO₄ were decreased by both xanthones in all tissues tested. Xanthones III and V also prevented the GR activity depletion induced by pro-oxidant activity only in the brain.
  
  
  CONCLUSIONS
  Altogether, the collected evidence suggests that xanthones can play a role as potential agents to attenuate the oxidative damage produced by different pro-oxidants.
authors.affiliation: Departamento de Neuroquímica, Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez, Insurgentes Sur 3877, S,S,A,, México, DF 14269, México. veped@yahoo.com.mx.
authors.forename: Tonali
authors.initials: T
authors.lastname: Blanco-Ayala
authors.forename: Rafael
authors.initials: R
authors.lastname: Lugo-Huitrón
authors.forename: Elizabeth M
authors.initials: EM
authors.lastname: Serrano-López
authors.forename: Ricardo
authors.initials: R
authors.lastname: Reyes-Chilpa
authors.forename: Edgar
authors.initials: E
authors.lastname: Rangel-López
authors.forename: Benjamín
authors.initials: B
authors.lastname: Pineda
authors.forename: Omar Noel
authors.initials: ON
authors.lastname: Medina-Campos
authors.forename: Laura
authors.initials: L
authors.lastname: Sánchez-Chapul
authors.forename: Enrique
authors.initials: E
authors.lastname: Pinzón
authors.forename: Trejo-Solis
authors.initials: TS
authors.lastname: Cristina
authors.forename: Daniela
authors.initials: D
authors.lastname: Silva-Adaya
authors.forename: José
authors.initials: J
authors.lastname: Pedraza-Chaverrí
authors.forename: Camilo
authors.initials: C
authors.lastname: Ríos
authors.forename: Verónica Pérez
authors.initials: VP
authors.lastname: de la Cruz
authors.forename: Mónica
authors.initials: M
authors.lastname: Torres-Ramos
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D001923:Brain Chemistry / Q000187:drug effects; D029759:Calophyllum / Q000737:chemistry*; D004249:DNA Damage / Q000187:drug effects; D005296:Ferrous Compounds / Q000633:toxicity*; D005980:Glutathione Reductase / Q000378:metabolism; D007668:Kidney / Q000737:chemistry / Q000187:drug effects; D015227:Lipid Peroxidation / Q000187:drug effects; D008099:Liver / Q000737:chemistry / Q000187:drug effects; D008297:Male; D010084:Oxidation-Reduction / Q000187:drug effects; D018384:Oxidative Stress / Q000187:drug effects*; D051381:Rats; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000378:metabolism; D044004:Xanthones / Q000494:pharmacology*
chemical_list: D000975:Antioxidants; D005296:Ferrous Compounds; D017382:Reactive Oxygen Species; D044004:Xanthones; C020748:ferrous sulfate; D005980:Glutathione Reductase