作为一种重金属, 铜在水中对水生生物具有毒性, 会引起氧化应激和脂肪沉积。然而, 目前尚无有效的饮食策略来预防铜暴露造成的损害。本研究通过对铜暴露的大口黑鲈（Micropterus salmoides）在鱼肽水解（HFP）预处理后对其铜累积、抗氧化酶、脂肪合成酶、脂质代谢相关基因表达水平和代谢途径进行综合评估。结果表明，添加1%（P < 0.05）、3%（P < 0.01）和5%（P < 0.05）的HFP显著降低了大口黑鲈中的铜累积。鱼肽水解物补充显著降低了总抗氧化能力（P < 0.01）和过氧化氢酶（P < 0.01）的活性，以及还原型谷胱甘肽（P < 0.01）和丙二醛（P < 0.05）的含量。添加3%（P < 0.05）和5% HFP（P < 0.05）的鱼中脂肪酸合酶浓度显著降低。同样，饲喂3%（P < 0.05）和5%（P < 0.01）HFP的鱼显著降低了葡萄糖-6-磷酸脱氢酶的浓度。血清代谢组学分析显示，添加1%、3%和5% HFP的鱼获得了85、144和207个差异代谢物。差异代谢物主要是脂质和类脂类分子, 与脂质代谢途径相关。添加3% HFP（P < 0.01）和5% HFP（P < 0.001）的鱼中脂肪酸合酶（P < 0.01）、类固醇调节元件结合蛋白-1c（P < 0.05）、肝X受体（P < 0.001）、过氧化物酶体增殖活化γ（P < 0.01）、载脂蛋白B（P < 0.001）和脂肪酸结合蛋白1的表达水平（P < 0.01）显著下调, 肉碱棕榈酰转移酶1α（P < 0.01）、激素敏感组织脂解酶（P < 0.001）和载脂蛋白A 1（P < 0.05）的表达水平显著上调。此外, 添加3% HFP（P < 0.01）和5% HFP（P < 0.001）的鱼中B细胞淋巴瘤-2基因的表达水平也显著上调, 并呈剂量依赖效应。综上所述, 本研究证实了HFP补充与大口黑鲈铜暴露引起的氧化应激、酶活性和相关代谢途径以及细胞凋亡密切相关, 总体上缓解了铜暴露引起的脂肪沉积的现象。版权所有 © 2023. 由Elsevier Inc.发表。

As a heavy metal, copper is toxic to aquatic organisms in water, causing oxidative stress and lipid deposition. However, there is currently no effective dietary strategy to prevent damage caused by copper exposure. Here, copper bioaccumulation, antioxidant enzymes, lipogenic enzymes, lipid metabolism-related gene expression levels and metabolic pathways were synthesized and evaluated in copper-exposed largemouth bass (Micropterus salmoides) after hydrolysis fish peptides (HFP) pretreatment. The results showed that supplementation with 1% (P < 0.05), 3% (P < 0.01) and 5% (P < 0.05) HFP significantly reduced the copper bioaccumulation in largemouth bass. Hydrolysis fish peptides supplementation significantly reduced the activities of total antioxidant capacity (P < 0.01) and catalase (P < 0.01) and the contents of glutathione (P < 0.01) and malondialdehyde (P < 0.05). Fatty acid synthetase concentration was significantly reduced in fish supplemented with 3% (P < 0.05) and 5% HFP (P < 0.05). Similarly, fish fed 3% (P < 0.05) and 5% (P < 0.01) HFP significantly reduced the glucose-6-phosphate dehydrogenase concentration. Serum metabolomics revealed that 85, 144 and 207 differential metabolites were obtained in fish supplemented with 1%, 3% and 5% HFP, respectively. The differential metabolites were mainly lipids and lipid-like molecules, which were associated with the lipid metabolism pathways. The expression levels of fatty acid synthase (P < 0.01), sterol regulatory element binding protein-1c (P < 0.05), liver X receptor (P < 0.001), peroxisome proliferator activated γ (P < 0.01), apolipoprotein B (P < 0.001) and fatty acid-binding protein 1 (P < 0.01) were significantly down-regulated and the expression levels of carnitine palmitoyltransferase 1α (P < 0.01), hormone-sensitive lipase (P < 0.001), apolipoprotein A 1 (P < 0.05) were significantly up-regulated in fish fed with 3% HFP. Additionally, supplementation with 3% (P < 0.01) and 5% (P < 0.001) HFP significantly up-regulated the expression level of B-cell lymphoma-2 with a dose-dependent effect. In conclusion, our study confirmed that HFP supplementation was closely associated with oxidative stress, enzymatic activities and related pathways of lipid metabolism, and apoptosis, and in general alleviated lipid deposition caused by copper exposure in largemouth bass.Copyright © 2023. Published by Elsevier Inc.