Toxicity and genotoxicity evaluation of Passiflora alata Curtis (Passifloraceae)

Abstract Passiflora alata is an official species of Brazilian Pharmacopoeia and its aerial parts are used as medicinal plant by local population as well as constitutes many phytomedicines commercialized in Brazil as sedative. Aims of study To evaluate the acute and sub-acute toxicity and genotoxicity of an aqueous spray-dried extract (PA) of Passiflora alata (2.6% flavonoids). Materials and methods The acute and the sub-acute toxicity was evaluated in mice and rats, respectively. Behavioural, biochemical, hematological, histological and urine parameters were considered. Genotoxicity was assessed by using micronucleus test performed in peripheral blood and bone marrow cells and comet assay in peripheral blood leukocytes. Results Mice deaths were not observed up to 4800 mg/kg, p.o. , single dose. Rats treated with aqueous extract at dose of 300 mg/kg, p.o. , for 14 days did not present biochemical, hematological or histopathological significant alterations when compared to control group. However, these rats showed signs of irritability and did not show weight gain. In addition, mice acutely treated with extract 150, 300 and 600 mg/kg, p.o. , presented DNA damage determined by comet assay in peripheral blood cells 3 h after treatment. The effect of lower doses (12.5, 25 and 50 mg/kg, p.o. ) was evaluated at 3, 6 and 24 h after treating. Only PA 50 mg/kg ( p.o. ) induced significant damage at 3 and 6 h. The maximum damage induction was observed at 6 h. When the animals received PA 12.5, 25 or 50 mg/kg/day during 3 days (i.e., 72 h treatment) DNA damage (comet and micronucleus tests) increased significantly in a dose-dependent manner. Conclusion In conclusion Passiflora alata presented genotoxic effect and deserves further toxicity evaluation in order to guarantee its safety for human use.