Department of Biology, Ecology and Earth Science, University of Calabria, Via P. Bucci 4/B, Rende, Cosenza, 87036, Italy.
Department of Biology, Arcadia University450 S Easton Rd, Glenside, PA, 19038, Boyer 340 2155172389, United States.
Aquat Toxicol. 2019 Jun;211:193-201. doi: 10.1016/j.aquatox.2019.04.009. Epub 2019 Apr 12.
Lead is one of the most alarming toxic pollutants for the environment due to its acute toxicity and high bioaccumulation tendency. Despite legislative efforts, world lead production has more than doubled since the early 1970s to 2016. Due to extensive exploitation and human activity, the coastal and estuarine regions belong to marine environments that are mostly and more rapidly deteriorated by pollutants including lead. A limited number of studies examined the effects of lead in fishes, compared to other aquatic models and even fewer studies have been dedicated to seawater fishes especially regarding Pb adsorption and accumulation in specific organs. Fish gills, key compartments involved in several crucial functions such as gas exchange, osmoregulation, and excretion, are also the organs in which Pb is mainly accumulated. Herein, we investigated the morphofunctional and ultrastructural modifications in the gills of a marine teleost (Thalassoma pavo) after acute exposure (48, 96, 192 h) to three lead concentrations. We showed that pathological alterations can be detected in all the examined samples. The most common modifications observed were: the curling of the lamellae and the dilation of their apical tips, the lamellar edema, the proliferation and the hypertrophy of CCs, the progressive epithelial disorganization with detachment of the epithelium from connective tissue. This study also demonstrates that there is a weak influence on the expression pattern of Na/K-ATPase and AQP3 biomarker enzymes while high metallothioneins expression has been observed. The described alterations may adversely affect gas exchange and ionic balance, with a long chain of cascading effects. This is the first evidence of the effects exerted by lead on gills of seawater fishes that highlights the harmful properties of this metal, even at low concentration.
铅是对环境最具警示性的有毒污染物之一，因为它具有急性毒性和高生物累积倾向。尽管立法努力，自 20 世纪 70 年代初以来，世界铅产量增加了一倍以上，达到 2016 年的水平。由于广泛的开发和人类活动，沿海和河口地区属于海洋环境，这些环境受到包括铅在内的污染物的影响最大且最快。与其他水生模型相比，少数研究检查了鱼类中的铅的影响，甚至更少的研究专门针对海水鱼类，特别是关于 Pb 在特定器官中的吸附和积累。鱼类的鳃是参与气体交换、渗透调节和排泄等几个关键功能的关键部位，也是主要积累 Pb 的器官。在此，我们研究了海洋硬骨鱼（Thalassoma pavo）在急性暴露（48、96、192 h）于三种铅浓度下后鳃的形态功能和超微结构变化。我们表明，可以在所有检查的样本中检测到病理变化。观察到的最常见的变化是：鳃片卷曲和其顶端的扩张，鳃片水肿，CC 的增殖和肥大，上皮与结缔组织分离的渐进性上皮组织紊乱。这项研究还表明，Na/K-ATPase 和 AQP3 生物标志物酶的表达模式受到微弱影响，而高金属硫蛋白的表达已被观察到。描述的变化可能会对气体交换和离子平衡产生不利影响，从而产生一系列级联效应。这是铅对海水鱼类鳃的影响的第一个证据，突出了这种金属的有害特性，即使在低浓度下也是如此。
