title: Antioxidant response of the hard shelled mussel Mytilus coruscus exposed to reduced pH and oxygen concentration.
abstract: Ocean acidification (OA) and hypoxic events are increasing worldwide problems, their interactive effects have not been well clarified, although their co-occurrence is prevalent. The East China Sea (the Yangtze River estuary area) suffers from not only coastal hypoxia but also pH fluctuation, representing an ideal study site to explore the combined effect of OA and hypoxia on marine bivalves. We experimentally evaluated the antioxidant response of the mussel Mytilus coruscus exposed to three pH levels (8.1, 7.7 and 7.3) at two dissolved oxygen (DO) levels (2.0mgL-1and 6.0mgL-1) for 72h. Activities of superoxide dismutase, catalase, glutathione peroxidase, acid phosphatase, and alkaline phosphatase and levels of malondialdehyde were measured in gills and hemolymph. All enzymatic activities in hemolymph and gills followed a similar pattern throughout the experiment duration. Generally, low DO showed greater effects on enzyme activities than elevated CO2. Significant interactions between DO, pH and time were only observed at superoxide dismutase and catalase in both tissues. PCA revealed positive relationships between most enzyme activities in both gills and hemolymph with the exception of alkaline phosphatase activity and the level of malondialdehyde in the hemolymph. Overall, our results suggested that decreased pH and low DO induced similar antioxidant responses in the hard shelled mussel, and showed an additive effect on most enzyme activities. The evaluation of multiple environmental stressors, a more realistic scenario than single ones, is crucial to predict the effect of future global changes on coastal species and our results supply some insights on the potential combined effects of reduced pH and DO on marine bivalves.
authors.affiliation: College of Fisheries and Life Science, Shanghai Ocean University, 999 Huchenghuan Road, Shanghai 201306, China; Key Laboratory of East China Sea and Oceanic Fishery Resources Exploitation, Ministry of Agriculture of China, East China Sea Fisheries Research Institute, Chinese Academy of Fisheries Sciences, Shanghai 20090, China. Electronic address: 416597727@qq.com.
authors.forename: Yanming
authors.initials: Y
authors.lastname: Sui
authors.affiliation: College of Fisheries and Life Science, Shanghai Ocean University, 999 Huchenghuan Road, Shanghai 201306, China; Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai 201306, China; Department of Integrative Ecophysiology, Alfred-Wegener-Institute Helmholtz Center for Polar, and Marine Research, Bremerhaven 27570, Germany. Electronic address: mhhu@shou.edu.cn.
authors.forename: Menghong
authors.initials: M
authors.lastname: Hu
authors.affiliation: College of Fisheries and Life Science, Shanghai Ocean University, 999 Huchenghuan Road, Shanghai 201306, China.
authors.forename: Yueyong
authors.initials: Y
authors.lastname: Shang
authors.affiliation: College of Fisheries and Life Science, Shanghai Ocean University, 999 Huchenghuan Road, Shanghai 201306, China.
authors.forename: Fangli
authors.initials: F
authors.lastname: Wu
authors.affiliation: College of Fisheries and Life Science, Shanghai Ocean University, 999 Huchenghuan Road, Shanghai 201306, China.
authors.forename: Xizhi
authors.initials: X
authors.lastname: Huang
authors.affiliation: Department of Biological and Environmental Sciences, University of Gothenburg, The Sven Lovén Centre for Marine Sciences - Kristineberg, Fiskebäckskil 45178, Sweden.
authors.forename: Sam
authors.initials: S
authors.lastname: Dupont
authors.affiliation: Department of Integrative Ecophysiology, Alfred-Wegener-Institute Helmholtz Center for Polar, and Marine Research, Bremerhaven 27570, Germany.
authors.forename: Daniela
authors.initials: D
authors.lastname: Storch
authors.affiliation: Department of Integrative Ecophysiology, Alfred-Wegener-Institute Helmholtz Center for Polar, and Marine Research, Bremerhaven 27570, Germany.
authors.forename: Hans-Otto
authors.initials: HO
authors.lastname: Pörtner
authors.affiliation: College of Fisheries and Life Science, Shanghai Ocean University, 999 Huchenghuan Road, Shanghai 201306, China; Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai 201306, China.
authors.forename: Jiale
authors.initials: J
authors.lastname: Li
authors.affiliation: College of Fisheries and Life Science, Shanghai Ocean University, 999 Huchenghuan Road, Shanghai 201306, China; Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai 201306, China. Electronic address: wqlv@shou.edu.cn.
authors.forename: Weiqun
authors.initials: W
authors.lastname: Lu
authors.affiliation: College of Fisheries and Life Science, Shanghai Ocean University, 999 Huchenghuan Road, Shanghai 201306, China; Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai 201306, China; Department of Integrative Ecophysiology, Alfred-Wegener-Institute Helmholtz Center for Polar, and Marine Research, Bremerhaven 27570, Germany. Electronic address: youjiwang2@gmail.com.
authors.forename: Youji
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D002245:Carbon Dioxide / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D002681:China; D005880:Gills / Q000187:drug effects / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000378:metabolism; D006458:Hemolymph / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D049878:Mytilus / Q000187:drug effects* / Q000201:enzymology; D018384:Oxidative Stress; D010100:Oxygen / Q000378:metabolism*; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D000975:Antioxidants; D002245:Carbon Dioxide; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D000469:Alkaline Phosphatase; D010100:Oxygen
keywords: Acidification; Antioxidant response; Hypoxia; Multiple stresses; Mytilus coruscus; pH