RESUMEN
OBJECTIVES: The aim of this work was to study the effects of P. major against the oxidative damage of isolated rat liver mitochondria. METHODS: The extracts were obtained using methanol (MeOH), ethyl acetate (EAc), dichloromethane (DCM), and hexane (Hex) as solvents. KEY FINDINGS: Hex, DCM, and EAc totally, and MeOH partially, inhibited ROS generation and lipid peroxidation of membranes induced by Fe(2+) or t-BOOH. However, only MeOH was able to prevent the t-BOOH-induced glutathione and NAD(P)H oxidation. All extracts chelated Fe(2+) and reduced DPP Hradicals. EPR analysis revealed that P. major exhibited potent scavenger activity for hydroxyl radicals. CONCLUSIONS: The potent antioxidant activity exhibited by P. major was able to prevent oxidative mitochondrial damage, contributing to the understanding of its hepatoprotective action against ROS-mediated toxicity.
Asunto(s)
Antioxidantes/farmacología , Radical Hidroxilo/metabolismo , Hígado/efectos de los fármacos , Mitocondrias Hepáticas/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/farmacología , Plantago , Animales , Compuestos de Bifenilo/metabolismo , Quelantes/farmacología , Depuradores de Radicales Libres/farmacología , Glutatión/metabolismo , Hierro/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Hígado/metabolismo , Masculino , Mitocondrias Hepáticas/metabolismo , NADP/metabolismo , Picratos/metabolismo , Ratas , Ratas Wistar , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Baccharis dracunculifolia DC (Asteraceae) is the main botanical source used by honeybees to produce Brazilian green propolis whose hepatoprotective properties have been already described. In this work we investigated the protective effects of the glycolic extract of B. dracunculifolia (GEBd) against oxidative stress in isolated rat liver mitochondria (RLM). The GEBd was prepared by fractionated percolation using propylene glycol as solvent. The total phenols and flavonoids, which are substances with recognized antioxidant action, were quantified in GEBd and the phytochemical analysis was carried out by HPLC. GEBd exhibited significant scavenger activity towards DPPH radicals and superoxide anions in a concentration-dependent manner, and also a Fe2+ chelating activity. GEBd decreased the basal H2O2 generation and the Fe2+- or t-BuOOH-induced ROS production in isolated mitochondria. Lipid oxidation of mitochondrial membranes, protein thiol groups and GSH oxidation were also prevented by GEBd. This shows that B. dracunculifolia exhibit potent antioxidant activity protecting liver mitochondria against oxidative damage and such action probably contribute to the antioxidant and hepatoprotective effects of green propolis.