Benzo(a)pyrene-induced metabolic responses in Manila clam Ruditapes philippinarum by proton nuclear magnetic resonance ((1)H NMR) based metabolomics

Benzo(a)pyrene is an important polycyclic aromatic hydrocarbon (PAH) which causes carcinogenic, teratogenic and mutagenic effects in various species and the level of contamination of this toxic agent in the marine environment is of great concern. In this study, metabolic responses induced by two doses (0.02 and 0.2 μM) of BaP were characterized in the gill tissues of Manila clam Ruditapes philippinarum after exposure for 24, 48 and 96 h. The high dose (0.2 μM) of BaP induced the disturbances in energy metabolism and osmotic regulation based on the metabolic biomarkers such as succinate, alanine, glucose, glycogen, branched chain amino acids, betaine, taurine, homarine, and dimethylamine in clam gills after 24 h of exposure. In addition, hormesis induced by BaP was found in clams exposed to both doses of BaP. Overall, our results demonstrated the applicability of metabolomics for the elucidation of toxicological effects of marine environmental contaminants in a selected bioindicator species such as the Manila clam.