Mercury (Hg) is among the most deleterious contaminant in the aquatic environment and presents a serious risk to humans and ecosystems. This study evaluated the effects of Hg on oxidative stress biomarkers, DNA integrity and histological structure of the respiratory tree of Holothuria forskali exposed to different concentrations of mercury chloride HgCl2 (0.04, 0.08 and 0.16 mg L-1) for 96 h. Exposure of H. forskali to Hg led to oxidative stress with an increase in Malondialdehyde (MDA), hydrogen peroxide (H2O2), advanced oxidation protein product (AOPP) and protein carbonyls (PCO) levels in the treated groups. Alteration of the antioxidant system was also confirmed by the significant increase in glutathione (GSH), nonprotein thiol (NPSH) and vitamin C contents. Moreover, the enzymatic activity of superoxide dismutase (SOD), Glutathione peroxidase (GPX) and Catalase (CAT) increased significantly. Our research revealed that total Metallothionein (MTs) content enhanced in a dose-dependent manner. Interestingly, the exposure to this metal provoked a decrease in Acetylcholinesterase (AChE) activity. Hg genotoxicity was further evidenced by a random DNA degradation that was observed in the treated groups. The histopathological findings confirmed the biochemical results. Overall, our results indicated that mercury-induced genotoxicity, oxidative damage and histopathological injuries in the respiratory tree of H. forskali.

中文翻译：

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汞破坏海参呼吸树（Holothuria forskali）的氧化还原状态，上调金属硫蛋白并诱导遗传毒性。

汞是水生环境中最有害的污染物之一，对人类和生态系统构成了严重的风险。本研究评估了汞对暴露于不同浓度的氯化汞HgCl2（0.04、0.08和0.16 mg L-1）96 h的Holothuria forskali呼吸树的氧化应激生物标志物，DNA完整性和组织学结构的影响。Forskali暴露于Hg会导致氧化应激，导致治疗组丙二醛（MDA），过氧化氢（H2O2），高级氧化蛋白产物（AOPP）和蛋白羰基（PCO）含量增加。谷胱甘肽（GSH），非蛋白硫醇（NPSH）和维生素C含量的显着增加也证实了抗氧化剂系统的改变。此外，超氧化物歧化酶（SOD）的酶促活性 谷胱甘肽过氧化物酶（GPX）和过氧化氢酶（CAT）显着增加。我们的研究表明，总金属硫蛋白（MTs）含量呈剂量依赖性增加。有趣的是，暴露于这种金属导致乙酰胆碱酯酶（AChE）活性降低。在治疗组中观察到的随机DNA降解进一步证明了Hg的遗传毒性。组织病理学结果证实了生化结果。总的来说，我们的结果表明，汞引起的遗传毒性，福克斯卡利呼吸树的氧化损伤和组织病理学损伤。在治疗组中观察到的随机DNA降解进一步证明了Hg的遗传毒性。组织病理学结果证实了生化结果。总的来说，我们的结果表明，汞引起的遗传毒性，福克斯卡利呼吸树的氧化损伤和组织病理学损伤。在治疗组中观察到的随机DNA降解进一步证明了Hg的遗传毒性。组织病理学结果证实了生化结果。总的来说，我们的结果表明，汞引起的遗传毒性，福克斯卡利呼吸树的氧化损伤和组织病理学损伤。