文献类型： 外文期刊

作者： Pu, Yan ¹ ; Guo, Jie ² ; Yang, Hao ² ; Zhong, Liqiao ² ; Tian, Huiwu ² ; Deng, Huatang ² ; Duan, Xinbin ² ; Liu, Shaoping ² ; Chen, Daqing ¹ ;

作者机构： 1.Southwest Univ, Sch Life Sci, Key Lab Freshwater Fish Reprod & Dev Minist Educ, Chongqing 400715, Peoples R China

2.Chinese Acad Fishery Sci, Yangtze River Fisheries Res Inst, Fishery Resources & Environm Sci Expt Stn Uppermid, Minist Agr & Rural Affairs, Wuhan 430223, Peoples R China

3.Nanjing Agr Univ, Wuxi Fisheries Coll, Wuxi 214081, Peoples R China

4.Southwest Univ, Coll Fisheries, Fisheries & Aquaculture Biotechnol Lab, Chongqing 400715, Peoples R China

关键词： Mercury; Growth; Growth hormone/insulin-like growth factor; (GH/IGF) axis; Oxidative stress Hypophthalmichthys molitrix

期刊名称：ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY （ 影响因子：7.129； 五年影响因子：7.284 ）

ISSN： 0147-6513

年卷期： 2022 年 236 卷

页码：

收录情况： SCI

摘要： Mercury (Hg) is a global environmental contaminant, and excessive mercury levels in water can adversely affect the growth of fish. Silver carp (Hypophthalmichthys molitrix) is one of the important freshwater aquaculture fish in China, and its natural resources have been critically declining. However, the effects of Hg2+ exposure on the growth hormone/insulin-like growth factor (GH/IGF) axis and its toxic mechanism are still unclear. In this study, we systematically evaluated the bioaccumulation, histomorphology, antioxidant status, hormone levels, and GH/ IGF axis toxicity of juvenile silver carp after exposure to environmental-related concentrations of Hg2+ (0, 0.05, 0.5, 5, and 50 mu g/L) for 28 days. Results showed that the Hg2+ bioaccumulation in the liver increased with a rise in Hg2+ concentration and time of exposure. The body length (BL), body weight (BW), weight growth rate (WGR) and specific growth rate (SGR) all decreased after Hg2+ exposure. The serum levels of growth hormones (GH and IGF) and thyroid hormones (T3 and T4) were significantly decreased, and the expressions of GH/IGF axis-related genes were significantly downregulated after 7, 14, and 28 days of Hg2+ exposure. Correlations between the growth parameters and growth hormones or expression of genes in GH/IGF axis further suggested that environmentally relevant concentrations of Hg2+ could have adverse effects on growth. In addition, with increasing Hg(2+ )exposure, superoxide activities of dismutase (SOD), catalase (CAT), and glutathione S-transferase (GST)and levels of reduced glutathione (GSH) and malondialdehyde (MDA) were significantly increased, whereas the activity of glutathione peroxidase (GPx) significantly decreased and oxidative stress-related gene significantly changed. Liver lesions were mainly characterized by inflammatory cell infiltration, hepatocyte necrosis and fat vacuolation after exposure to Hg2+. Taken together, the results indicate that Hg2+ exposure leads to growth inhibition and oxidative stress in juvenile silver.