Department of Aquatic Life Medicine, Pukyong National University, Busan, 608-737, Republic of Korea.
West Sea Fisheries Research Institute, National Institute of Fisheries Science, Taean, Republic of Korea; Department of Aquatic Life and Medical Science, Sun Moon University, Assn-si, Republic of Korea.
Fish Shellfish Immunol. 2021 Apr;111:119-126. doi: 10.1016/j.fsi.2021.01.010. Epub 2021 Jan 24.
There are few reports of dietary Cu (copper) toxicity to Korean bullhead, Pseudobagrus fulvidraco, and little is known about recovery from dietary Cu exposure. In this study, P. fulvidraco (mean length 16.9 ± 1.38 cm, and mean weight 53.2 ± 1.22 g) were exposed for 4 weeks to dietary Cu concentration of 0 (control), 700, 900, and 1100 mg Cu kg dry feed to establish maximum tolerable levels of dietary Cu. All fish were then fed the dietary EGCG (Epigallocatechin gallate) concentration of 100 and 500 mg EGCG kg dry feed for a further 2 weeks to assess recovery. We were measured bioaccumulation (in the intestine, liver, and gill tissue), antioxidant enzymes (SOD and CAT) and immune responses (lysozyme and phagocytosis). The Cu exposure induced a significant accumulation in the intestine, liver, and gill tissues and the highest accumulation was observed in intestinal tissues (17-34 fold), but dietary EGCG exposure decreased (about 0.8-fold) Cu concentration in each tissue (ANOVA, P < 0.05). In antioxidant enzymes, SOD and CAT significantly increased by approximately 1.6-fold by dietary Cu exposure in the liver and gill tissue, respectively, but dietary EGCG exposure decreased SOD and CAT by about 1.1-fold, respectively (ANOVA, P < 0.05). For immune responses, lysozyme and phagocytosis in the blood significantly were decreased by approximately 1.5-fold, respectively, by dietary Cu exposure, but dietary EGCG exposure increased lysozyme and phagocytosis by about 1.1-fold, respectively (ANOVA, P < 0.05). During recovery period, bioaccumulation, antioxidant enzymes (SOD and CAT activity), and immune response (lysozyme and phagocytosis activity) tended to alleviate the significant changes by Cu exposure, and the tendency to return normal state was observed in high level of EGCG. The result of this study indicate that Cu exposure to P. fulvidraco affects bioaccumulation, antioxidant enzymes, and immune responses, and high level of EGCG were effective to alleviate the toxic effects of Cu exposure.
目前关于铜（Cu）毒性对韩国七鳃鳗（Pseudobagrus fulvidraco）的影响的报道较少，人们对其从 Cu 暴露中恢复的过程也知之甚少。在本研究中，采用平均体长为 16.9±1.38cm、平均体重为 53.2±1.22g 的七鳃鳗幼鱼，在为期 4 周的时间里，分别投喂 0（对照）、700、900 和 1100mg/kg 干饲料 Cu 的饲料，以确定饲料中 Cu 的最大耐受水平。随后，所有的鱼均投喂 100 和 500mg/kg 干饲料的 EGCG（表没食子儿茶素没食子酸酯）饲料 2 周，以评估其恢复情况。我们测量了生物累积（在肠道、肝脏和鳃组织中）、抗氧化酶（SOD 和 CAT）和免疫反应（溶菌酶和吞噬作用）。Cu 暴露会导致肠道、肝脏和鳃组织中 Cu 的显著积累，在肠道组织中的积累最高（17-34 倍），但 EGCG 暴露会使每种组织中的 Cu 浓度降低（约 0.8 倍）（方差分析，P<0.05）。在抗氧化酶方面，肝脏和鳃组织中的 SOD 和 CAT 分别因 Cu 暴露而显著增加了约 1.6 倍，但 EGCG 暴露使 SOD 和 CAT 分别降低了约 1.1 倍（方差分析，P<0.05）。对于免疫反应，Cu 暴露使血液中的溶菌酶和吞噬作用分别显著降低了约 1.5 倍，但 EGCG 暴露使溶菌酶和吞噬作用分别增加了约 1.1 倍（方差分析，P<0.05）。在恢复期间，生物累积、抗氧化酶（SOD 和 CAT 活性）和免疫反应（溶菌酶和吞噬作用活性）的变化趋势表明，Cu 暴露的显著变化得到了缓解，而且在高 EGCG 水平下，这些变化有恢复正常状态的趋势。本研究结果表明，Cu 暴露会影响七鳃鳗的生物累积、抗氧化酶和免疫反应，而高浓度的 EGCG 可以有效缓解 Cu 暴露的毒性作用。
