Hepatoprotective properties from the seaweed Bryothamnion triquetrum (S.G.Gmelin) M.A.Howe against CCl4-induced oxidative damage in rats

Context: Seaweeds are seen as a traditional food and folk medicine by different coastal countries. The red seaweed Bryothamnion triquetrum is a widely distributed species that grows in shallow waters, and different authors have demonstrated a possible application of the seaweeds as a source of natural antioxidants and relative diseases. Aims: To evaluate the hepatoprotective properties on CCl4-induced oxidative stress in rats that were associated with the antioxidant activity from the polyphenol-rich fractions of the red seaweed Bryothamnion triquetrum. Methods: Polyphenols were determined by Folin-Cioacalteu. Antioxidant activity from phenolic compounds-rich fractions was measured by different assays (DPPH, Reducing power, β-Carotene/linoleic acid assay and Inhibition of lipoperoxidation). Aqueous extract from B. triquetrum was administered during 20 days to rats and submitted CCl4-Induced oxidative damage. The peroxidation and hepatic damage (TBARS, ASAT and ALAT), antioxidant metabolite and enzymes (glutathione, catalase and superoxide dismutase) were evaluated. Also, it was evaluated the expression of antioxidant enzymes by RT-PCR. Results: The antioxidant activity determined by different assays with polyphenolic fractions. Free Phenolic Acid was more active: DPPH, 20 µg 87%; Reducing power OD = 0.490, 20 µg ; β-carotene/linoleic acid 1 µg 53%, and inhibition of lipid peroxidation 0.250 µg 100%. Rats treated displayed lower liver TBARS, ASAT and ALAT than CCl4-treated group and catalase activity was increased. It was demonstrated expression of catalase. Conclusions: Data suggest that Bryothamnion triquetrum protects the liver against oxidative stress by modulating its antioxidant enzymes and oxidative status with potential use as phytodrug or functional food.