title: Croton cajucara Benth. leaf extract scavenges the stable free radical DPPH and protects against oxidative stress induced by paraquat.
abstract: Antioxidant effects of extracts from Croton cajucara BENTH. leaves was investigated in different in vitro and in vivo models. Extracts showed inhibitory radical scavenging activity against the stable radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) (75%, 43% and 25% of the standard trolox at 1, 10 and 100 mg/ml, respectively; IC50 218 mg/ml). Percentage survival of Saccharomyces cerevisiae cells treated with 10 mM paraquat increased by 21% and 55%, when 1 mg/ml and 10 mg/ml concentrations of the extract, respectively, were added. The cytosolic concentration of TBARS increased in animals treated with paraquat (+283%), while values did not significantly differ from the controls in rats additionally receiving the leaf extract. Paraquat administration also induced a significant increase in hydroperoxide-initiated chemiluminiscence (+76%), that was partially prevented by the leaf extract (+31%). Liver SOD activity was a 158% higher in animals receiving paraquat as compared to the controls. This effect was abolished by administration of the leaf extract. Paraquat administration did not significantly modify the activity of GPx or catalase. Croton cajucara extract increased GPx and catalase activities in paraquat treated-animals by 342% and 70%, respectively. Our results confirm that Croton cajucara leaf extract present radical scavenging activity and reduce oxidative stress induced by paraquat, suggesting the beneficial use as a potential source of antioxidant agents of natural origin.
authors.affiliation: Laboratório de Estresse Oxidativo, Universidade Luterana do Brasil, Porto Alegre, Brazil.
authors.forename: Marcelo
authors.initials: M
authors.lastname: Tieppo
authors.forename: Marilene
authors.initials: M
authors.lastname: Porawski
authors.forename: Mirian
authors.initials: M
authors.lastname: Salvador
authors.forename: Andrea Janz
authors.initials: AJ
authors.lastname: Moreira
authors.forename: Pilar Sanzchez
authors.initials: PS
authors.lastname: Collado
authors.forename: Javier
authors.initials: J
authors.lastname: González-Gallego
authors.forename: Norma Possa
authors.initials: NP
authors.lastname: Marroni
mesh_terms: D000818:Animals; D001713:Biphenyl Compounds; D029802:Croton / Q000737:chemistry*; D016166:Free Radical Scavengers / Q000737:chemistry / Q000494:pharmacology*; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008163:Luminescent Measurements; D008297:Male; D016877:Oxidants / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects*; D010269:Paraquat / Q000037:antagonists & inhibitors* / Q000633:toxicity*; D010851:Picrates / Q000378:metabolism; D010936:Plant Extracts / Q000737:chemistry; D018515:Plant Leaves / Q000737:chemistry; D051381:Rats; D017208:Rats, Wistar; D012441:Saccharomyces cerevisiae / Q000187:drug effects; D013482:Superoxide Dismutase / Q000378:metabolism; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism
chemical_list: D001713:Biphenyl Compounds; D016166:Free Radical Scavengers; D016877:Oxidants; D010851:Picrates; D010936:Plant Extracts; D017392:Thiobarbituric Acid Reactive Substances; C004931:1,1-diphenyl-2-picrylhydrazyl; D013482:Superoxide Dismutase; D010269:Paraquat