de Moraes Alencastre Sarah Hoffman, Vassallo Dalton Valentim, Wiggers Giulia Alessandra, Miguel-Castro Marta, Ávila Renata Andrade, Dos Santos Leonardo, Schereider Ingridy Reinholz Grafites
Health Science Center of Vitória - EMESCAM, Vitória, ES, Brazil.
Department of Physiological Sciences, Health Sciences Center, Universidade Federal Do Espírito Santo, Av. Marechal Campos 1468, Vitória, ES, 29040-091, Brazil.
Cardiovasc Toxicol. 2025 Jun 25. doi: 10.1007/s12012-025-10032-4.
Mercury exposure triggers localized oxidative stress, playing a central role in its detrimental effects, because toxic levels of ROS induce lipid peroxidation, promote protein oxidation and nitration, and nucleic acid oxidation and damage. Egg white hydrolysate (EWH), a functional food, is a protein extract that has promising capabilities against metal-induced cardiovascular damage. However, its potential in preventing the acute effects of mercury exposure remains unexplored. This study evaluated the preventive efficacy of 3 days, a short-term EWH treatment against the subsequent acute exposure to HgCl in isolated left ventricle papillary muscles. Male Wistar rats were divided into four groups: Control, EWH, HgCl and EWH + HgCl. Animals received filtered water or EWH (1 g/kg/day) via oral gavage for 3 days as pre-treatment. Subsequently, papillary muscles were isolated, and then HgCl and EWH + HgCl groups were exposed to 6 nM HgCl for 60 min. Results revealed that acute HgCl exposure impaired force generation, positive and negative time derivatives of force, indicating contractile dysfunction. Notably, these effects were absent in the EWH + HgCl group. Furthermore, HgCl exposure depressed post-rest potentiation, inotropic response protocols to calcium and isoproterenol while the EWH + HgCl group exhibited comparable responses to the control group. Besides that, the increase in ROS levels induced by HgCl in vitro was prevented by EWH pre-treatment. In conclusion, EWH demonstrated a cardioprotective effect by preserving contractile function, maintaining physiological inotropic responses, and preventing ROS accumulation with a remarkably brief 3-day pre-treatment period, highlighting its potential against the deleterious effects of acute mercury exposure, particularly in unavoidable or unpredictable exposures.
汞暴露会引发局部氧化应激，在其有害影响中起核心作用，因为有毒水平的活性氧会诱导脂质过氧化、促进蛋白质氧化和硝化以及核酸氧化和损伤。蛋清水解物（EWH）作为一种功能性食品，是一种蛋白质提取物，具有对抗金属诱导的心血管损伤的潜力。然而，其预防汞暴露急性影响的潜力尚未得到探索。本研究评估了短期（3天）EWH治疗对离体左心室乳头肌随后急性暴露于HgCl₂的预防效果。雄性Wistar大鼠分为四组：对照组、EWH组、HgCl₂组和EWH + HgCl₂组。动物通过口服灌胃接受过滤水或EWH（1 g/kg/天），持续3天作为预处理。随后，分离乳头肌，然后HgCl₂组和EWH + HgCl₂组暴露于6 nM HgCl₂ 60分钟。结果显示，急性HgCl₂暴露损害了力的产生、力的正负时间导数，表明收缩功能障碍。值得注意的是，这些影响在EWH + HgCl₂组中不存在。此外，HgCl₂暴露降低了静息后增强、对钙和异丙肾上腺素的变力反应方案，而EWH + HgCl₂组表现出与对照组相当的反应。除此之外，EWH预处理可预防HgCl₂在体外诱导的活性氧水平升高。总之，EWH通过保留收缩功能、维持生理变力反应以及在仅3天的预处理期内预防活性氧积累，显示出心脏保护作用，突出了其对抗急性汞暴露有害影响的潜力，特别是在不可避免或不可预测的暴露中。
