Avaliação das atividades hepatoprotetora e antioxidante; e da toxicidade aguda do extrato aquoso das folhas de apeiba tibourbou aubl (tiliaceae) em ratos (rattus norvegicus) e camundongos (mus musculus)

Abstract

Liver performs many biological functions, especially the metabolism detoxification of xenobiotics and endogenous substances. However, this makes it a target for toxicants, which damage the liver’s production, mostly of reactive oxygen substances. In this context, the present study aimed to investigate, in vivo, the hepatoprotective and antioxidant activities of Apeiba tibourbou Aubl (Tiliaceae), and acute toxicity in vivo (mice and rats). Acute toxicity was measured with the aqueous extract from the leaves of Apeiba tibourbou (EAT) in mice (300 and 2000 mg.kg -1 , p.o.) and rats (2000 mg.kg -1 , p.o.). Hepatoprotective and anti-oxidant activities were performed in mice pretreated with EAT (400, 200, 100, 50 or 25 mg.kg-1 , p.o.) and 18 mg.kg-1 (p.o.) rosmarinic acid (RA), and subsequently exposed to CCl4:oil olive oil (1:1, 2 mg.kg -1 , i.p). The markers (AST, ALT, ALP and GGT and MDA) were measured in plasma, and (MDA) in liver lysate. The EAT, the acute toxicity test showed no signs of intoxication and even physiological changes, with LD50 (median lethal dose) estimated greater than 2000 mg.kg -1 (GHS Class 5 of the OECD). In the hepatoprotective test, higher doses (400 and 200 mg.kg -1 ) did not protect the liver from aggression produced by CCl4. However, lowest doses (50 or 25 mg.kg -1 ), in particular of 50 mg.kg -1 decreased by 31.50% and 20.63% concentration of AST and ALT, respectively, while the dose of 25 mg.kg -1 decreased by 57.18% compared to the GGT positive control. In lysate of the liver, the EAT showed only moderate antioxidant effect at the dose of 50 mg.kg -1 . Rosmarinic acid demonstrated antioxidant activity and hepatoprotective. In conclusion, the EAT in low doses, was able to protect the liver from damage caused by CCl4, showed antioxidant activity and has moderate trend in high doses, possibly be potentiator and/ or inducing liver damage.