title: Toxicological responses to acute mercury exposure for three species of Manila clam Ruditapes philippinarum by NMR-based metabolomics.
abstract: The Manila clam (Ruditapes philippinarum) has been considered a good sentinel species for metal pollution monitoring in estuarine tidal flats. Along the Bohai coast of China, there are dominantly distributed three species of clams (White, Liangdao Red and Zebra in Yantai population) endowed with distinct tolerances to environmental stressors. In this study, adductor muscle samples were collected from both control and acute mercury exposed White, Liangdao Red and Zebra clams, and the extracts were analyzed by NMR-based metabolomics to compare the metabolic profiles and responses to the acute mercury exposure to determine the most sensitive clam species capable of acting as abioindicator for heavy metal pollution monitoring. The major abundant metabolites in the White clam sample were branched-chain amino acids (leucine, isoleucine and valine), lactate, arginine, aspartate, acetylcholine, homarine and ATP/ADP, while the metabolite profile of Zebra clam sample comprised high levels of glutamine, acetoacetate, betaine, taurine and one unidentified metabolite. For the Liangdao Red clam sample, the metabolite profile relatively exhibited high amount of branched-chain amino acids, arginine, glutamate, succinate, acetylcholine, homarine and two unassigned metabolites. After 48h exposure of 20μgL(-1) Hg(2+), the metabolic profiles showed significant differences between three clam species, which included increased lactate, succinate, taurine, acetylcholine, betaine and homarine and decreased alanine, arginine, glutamine, glutamate, acetoacetate, glycine and ATP/ADP in White clam samples, and elevated succinate, taurine and acetylcholine, and declined glutamine, glycine, and aspartate in Liangdao Red clam samples, while the increased branched-chain amino acids, lactate, succinate, acetylcholine and homarine, and reduced alanine, acetoacetate, glycine and taurine were observed in the Zebra clam samples. Overall, our findings showed that White clams could be a preferable bioindicator for the metal pollution monitoring based on the more sensitive metabolic changes in the adductor muscle compared with other two (Liangdao Red and Zebra) clam species.
authors.affiliation: Key Laboratory of Coastal Zone Environment Processes, CAS, Shandong Provincial Key Laboratory of Coastal Zone Environment Processes, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, 17, Chunhui Rd, Laishan District, Yantai 264003, Shandong Province, PR China.
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Liu
authors.forename: Linbao
authors.initials: L
authors.lastname: Zhang
authors.forename: Liping
authors.initials: L
authors.lastname: You
authors.forename: Ming
authors.initials: M
authors.lastname: Cong
authors.forename: Jianmin
authors.initials: J
authors.lastname: Zhao
authors.forename: Huifeng
authors.initials: H
authors.lastname: Wu
authors.forename: Chenghua
authors.initials: C
authors.lastname: Li
authors.forename: Dongyan
authors.initials: D
authors.lastname: Liu
authors.forename: Junbao
authors.initials: J
authors.lastname: Yu
mesh_terms: D000818:Animals; D049872:Bivalvia / Q000378:metabolism*; D004784:Environmental Monitoring / Q000379:methods; D016018:Least-Squares Analysis; D009682:Magnetic Resonance Spectroscopy; D008628:Mercury / Q000633:toxicity*; D055432:Metabolomics; D009132:Muscles / Q000187:drug effects* / Q000378:metabolism; D025341:Principal Component Analysis; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D014874:Water Pollutants, Chemical; D008628:Mercury