The toxicity of malathion to Solea senegalensis was studied in a static renewal bioassay during its first month of larval life (between 4 and 30 dph). Through the use of different biomarkers and biochemical, cellular and molecular approaches (inhibition of cholinesterases [ChEs], changes in cytochrome P450-1A [CYP1A] and the study of histopathological alterations), the effects of three concentrations of malathion (1.56, 3.12, and 6.25 μg/L) have been analyzed. In subacute exposure, malathion inhibited cholinesterase activities (AChE, BChE, CbE) in a dose- and time-dependent manner, ranging the inhibition percentage from 20% to 90%. However, the expression levels of CYP1A and AChE transcripts or proteins were not modified. Additionally, exposure to malathion provoked histopathological alterations in several organ systems of Senegalese sole in a time- and dose dependent way, namely disruption of parenchymal architecture in the liver, epithelial desquamation, pyknotic nuclei and steatosis in the intestine, disorganization of supporting cartilage, and sings of hyperplasia and hypertrophy in the gills and degeneration of the epithelial cells from the renal tubules. Malathion exposure also provoked strong disorganization of cardiac fibers from the heart. The findings provide evidence that exposure to sublethal concentrations of malathion that provoked serious injury to the fish S. senegalensis, were below the expected environmental concentrations reported in many other ecosystems and different fish species,revealing a higher sensitivity for Solea senegalensis to malathion exposure, thus reinforcing its use as sentinel species for environmental pollution in coastal and estuarine environments.

中文翻译：

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塞内加尔鳎、塞内加尔鲥幼虫发育和变态过程中马拉硫磷的毒性：组织病理学障碍和对 B 型酯酶和 CYP1A 酶系统的影响

马拉硫磷对Solea senegalensis的毒性在幼虫生命的第一个月（4 到 30 dph 之间）在静态更新生物测定中进行了研究。通过使用不同的生物标志物和生化、细胞和分子方法（抑制胆碱酯酶 [ChEs]、细胞色素 P450-1A [CYP1A] 的变化和组织病理学改变的研究），三种浓度的马拉硫磷（1.56、3.12、和 6.25 μg/L) 进行了分析。在亚急性暴露中，马拉硫磷以剂量和时间依赖性方式抑制胆碱酯酶活性（AChE、BChE、CbE），抑制百分比从 20% 到 90%。然而，CYP1A 和 AChE 转录本或蛋白质的表达水平没有改变。此外，暴露于马拉硫磷会以时间和剂量依赖的方式在塞内加尔鳎的几个器官系统中引起组织病理学改变，即肝脏实质结构的破坏、上皮脱屑、小肠中的固缩核和脂肪变性、支持软骨的解体、鳃中的增生和肥大以及肾小管上皮细胞的退化。马拉硫磷暴露还引起心脏纤维的强烈紊乱。研究结果提供证据表明，暴露于亚致死浓度的马拉硫磷会对鱼类造成严重伤害 马拉硫磷暴露还引起心脏纤维的强烈紊乱。研究结果提供证据表明，暴露于亚致死浓度的马拉硫磷会对鱼类造成严重伤害 马拉硫磷暴露还引起心脏纤维的强烈紊乱。研究结果提供证据表明，暴露于亚致死浓度的马拉硫磷会对鱼类造成严重伤害小号。senegalensis，低于许多其他生态系统和不同鱼类物种报告的预期环境浓度，表明 Solea senegalensis 对马拉硫磷暴露具有更高的敏感性，从而加强了其作为沿海和河口环境污染的哨兵物种的用途。