Hepatoprotective effect of green propolis is related with antioxidant action in vivo and in vitro

Abstract

Niraldo Paulino, Aguinaldo P. Barbosa, Amarilis S. Paulino, Maria C. Marcucci

Objective: Propolis is a natural product produced by bees. In this study, the free radical scavenger and hepatoprotective activity of green propolis extract (G1) was investigated. Methods: In vitro experiments on guinea pig isolated trachea tissues and in vivo study on rat liver tissues were performed. Hepatic damage was induced by oral administration of carbon tetrachloride (CCl4) to rats. Hepatoprotective effect was monitored by histological analysis of neutrophil margination (NM) on liver, aspartate and alanine transaminases (AST, ALT), and gamma-glutamil transferase (γ-GT) activity. Results: Chemical constitution of G1 by high performance liquid chromatography analysis resulted in the presence of phenolic compounds. G1 produced a reduction of the relative activity of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. G1 also exhibited high superoxide radical and potent hydroxyl radical scavenging activity. On guinea pig isolated trachea tissues, G1 inhibited the superoxide radical-induced contraction in vitro. After CCl4 administration, AST, ALT and ?-GT activities were found to be increased; these levels were reduced with G1 treatment. Conclusion: Taken together, our results suggest a potent antioxidant effect of G1, related with hepatoprotective action on liver damage induced by CCl4.