Chemoprotective effects of Ulva lactuca (green seaweed) aqueous-ethanolic extract against subchronic exposure to benzo(a)pyrene by CYP1A1 inhibition in mice.

The protective effect of the supplementation with an aqueous-ethanolic extract obtained from Ulva lactuca (Delile) green seaweed on benzo[a] pyrene-induced damage in mice was evaluated. Animals were treated with oral doses of U. lactuca extract (100 and 400 mg/kg) for 9 weeks. They were exposed to 50 mg/kg of oral doses of benzo(a)pyrene starting from the second week and up to the fifth week. Groups treated with benzo(a)pyrene only (second to fifth weeks), sunflower oil (vehicle, 9 weeks), or U. lactuca extract (100 and 400 mg/kg, 9 weeks) were also included in the study. The treatment with 400 mg/kg of the extract ameliorated the oxidative damage, decreased IL-1β and TNF-α levels, and favorably regulated the antioxidant defenses compared with benzo(a)pyrene-exposed group. The benzo(a)pyrene-induced DNA damage was also reduced, as it was evidenced by the lower micronucleus formation in U. lactuca extract-supplemented animals. The extract protected the hepatic tissue, and it reduced the liver activity/expression of CYP1A1. These results altogether suggested a chemoprotective effect of U. lactuca extract against benzo(a)pyrene-induced-toxicity in mice, probably associated with an inhibitory effect of carcinogen bioactivation.