Toxicity and genotoxicity evaluation of Passiflora alata Curtis (Passifloraceae)

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.

To evaluate the acute and sub-acute toxicity and genotoxicity of an aqueous spray-dried extract (PA) of Passiflora alata (2.6% flavonoids).

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.

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 3h after treatment. The effect of lower doses (12.5, 25 and 50mg/kg, p.o.) was evaluated at 3, 6 and 24h after treating. Only PA 50mg/kg (p.o.) induced significant damage at 3 and 6h. The maximum damage induction was observed at 6h. When the animals received PA 12.5, 25 or 50mg/kg/day during 3 days (i.e., 72h treatment) DNA damage (comet and micronucleus tests) increased significantly in a dose-dependent manner.

In conclusion Passiflora alata presented genotoxic effect and deserves further toxicity evaluation in order to guarantee its safety for human use.