Larimichthys crocea is a suitable bioindicator for monitoring short-term Cd discharge along the coast: An experimental study. (April 2020)

• Record Type: Journal Article
• Authors: Zhu, Qin-Ling; Zhang, Xiao-Lin; Hu, Wei; Zhang, Jian-She; Zheng, Jia-Lang
• Is Part Of: Environmental pollution. Volume 259(2020)
• Publication Date: 2020-04
• Subjects: Biomarker -- Fish -- Pancreatic secretion -- Antioxidant response -- Cadmium; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2019.113849
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: The present study evaluated the feasibility of using a marine cage fish Larimichthys crocea as a model for monitoring short-time Cd discharge near the sewage outlet. Fish were exposed to 0, 20, 100, 500 and 2500 μg/L for 6 h. Cd concentrations in gills, and left and right lobes of hepatopancreas were examined as well as activity levels of antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), glutathion-S-transferase (GST), glutathione reductase (GR), lipid peroxidation, glutathione (GSH) and mRNA levels of 19 genes encoding these enzymes. Cd concentrations increased at 100, 500 and 2500 μg/L Cd in gill and at 2500 μg/L Cd in hepatopancreas. Lipid peroxidation increased and GSH levels declined in gills at 2500 μg/L Cd. On the contrary, oxidative damage was not observed in hepatopancreas but GSH levels increased at all tested concentrations of Cd in the left lobe and at 20 μg/L Cd in the right lobe. The enhanced antioxidant response was confirmed in gills due to the increased activity levels of antioxidant enzymes and the up-regulated mRNA levels of most genes. However, disordered antioxidant response was observed in hepatopancreas, showing a dose- and lobe-dependent effect. RNA-seq and q-PCR analyses were performed to investigate differently expressed genes between both lobes under different concentrations of Cd. The most significantly enriched pathway term was pancreatic secretion, where the right lobe showed higher mRNA levels of 18 genes encoding pancreatic digestive enzymes than the left one under Cd stress. Interestingly, both lobes had the same mRNA levels of digestive enzyme genes and antioxidant genes in fish without Cd exposure. Overall, Larimichthys crocea is very sensitive to environmental exposure to cadmium. The present study for the first time investigates Cd-induced antioxidant response in Larimichthys crocea, also is the first to find lobe-dependent effects in fish. Graphical abstract: Image 1 Highlights: Cd-induced effects were firstly investigated in Larimichthys crocea . Transcriptional and physiological responses to Cd were assessed in fish. ROS-scavenging and pancreatic secretion pathways were sensitively responsive to Cd. Lobe-dependent effects induced by Cd were firstly found in fish. Larimichthys crocea is a promising bioindicator for monitoring short-term Cd discharge.