Oxidative stress and genotoxic responses to resin acids in Mediterranean mussels

This study represents the first attempt to investigate the genotoxic effects and oxidative stress of resin acids in Mediterranean mussels (Mytilus galloprovincialis Lmk). Mussels were exposed to 2.7 microM abietic acid (AA) and dehydroabietic acid (DHAA) for 6, 12, 18, and 24h. Gill and hepatopancreas conjugation activity, antioxidant defense system, lipid peroxidation (LPO), and DNA damage were determined as reduced glutathione (GSH), glutathione S-transferase (GST) activity, glutathione peroxidase (GPx) activity, catalase (CAT) activity, LPO, and DNA strand breaks. AA caused significant GST inhibition in mussel gills at 12, 18, and 24h. Activity of the antioxidant enzymes, namely, GPx and CAT, was inhibited at 24 and 18 h, respectively, in mussel gills. A significant increase in gill LPO was observed at 24h. The DNA integrity of mussel hepatopancreas significantly decreased after 12 and 24 h exposure to AA. A significant increase in LPO was observed after 6h exposure to DHAA, in either mussel gills or hepatopancreas. DNA integrity was significantly decreased in mussel hepatopancreas after 12 and 24 h exposure to DHAA. AA induced oxidative damage and genotoxicity in mussels, because it promoted increases in LPO in gills and DNA strand breaks in hepatopancreas. DHAA promoted oxidative damage and genotoxicity in mussels, as significant increases were observed in LPO in gills and hepatopancreas and in DNA strand breaks in hepatopancreas.