Domingues I, Oliveira R, Soares A M V M, Amorim M J B
Departamento de Biologia & CESAM, Universidade de Aveiro, Campus de Santiago, CEP 3810-193, Aveiro, Portugal.
Laboratório de Genética Toxicológica, Departamento de Genética e Morfologia, Instituto de Ciências Biológicas, Universidade de Brasília, Asa Norte, Brasília, DF, 70910-900, Brazil.
Ecotoxicology. 2016 Apr;25(3):491-9. doi: 10.1007/s10646-015-1607-5. Epub 2016 Jan 14.
Ivermectin (IVM) is a broad acting antihelmintic used in various veterinary pharmaceuticals. It has been shown that IVM enters the aquatic compartment and adversely affects organisms including fish. This study is based on the hypothesis that long term exposure to IVM affects fish and thus, the main objective was to assess the chronic effects of 0.25 and 25 µg IVM/L to zebrafish using multiple endpoints representative of several levels of biological organization: weight, behaviour (swimming and feeding) and subcellular markers including biomarkers for oestrogenicity (vitellogenin-VTG), oxidative stress (catalase-CAT and glutathione-S-transferase-GST) and neurotransmission (cholinesterase-ChE). Concentrations as low as 0.25 µg IVM/L disrupted the swimming behaviour, causing fish to spend more time at the bottom of aquaria. Such reduction of the swimming performance affected the feeding ability which is likely responsible for the weight loss. The effects on weight were gender differentiated, being more pronounced in males (0.25 µg IVM/L) than in females (25 µg IVM/L). Fish exposed to 25 µg/L exhibited darker coloration and mild curvature of the spine. No effects on VTG and AChE were observed, but a reduction on CAT and GST levels was observed in fish exposed to 25 µg IVM/L, although these alterations probably only reflect the general condition of the fish which was significantly compromised at this concentration. Despite that predicted environmental concentrations of IVM are below 0.25 µg/L, the behavioural effects may be translated into important ecological impacts, e.g. at predator-prey interactions where fish competitive advantage can be decreased. Future work should address the link between behaviour disruption and population fitness. The current study was based on a one experiment and multiple endpoint (anchored) approach, allowing the results to be integrated and linked towards a mechanistic understanding.
伊维菌素（IVM）是一种广泛应用于各种兽用药品的抗蠕虫药。研究表明，IVM进入水生环境并对包括鱼类在内的生物产生不利影响。本研究基于长期接触IVM会影响鱼类这一假设，因此，主要目的是使用代表生物组织多个水平的多个终点指标，评估0.25和25μg IVM/L对斑马鱼的慢性影响：体重、行为（游泳和摄食）以及亚细胞标志物，包括雌激素活性生物标志物（卵黄蛋白原-VTG）、氧化应激标志物（过氧化氢酶-CAT和谷胱甘肽-S-转移酶-GST）和神经传递标志物（胆碱酯酶-ChE）。低至0.25μg IVM/L的浓度就会扰乱游泳行为，使鱼在水族箱底部停留的时间更长。游泳能力的下降影响了摄食能力，这可能是体重减轻的原因。对体重的影响存在性别差异，在雄性（0.25μg IVM/L）中比在雌性（25μg IVM/L）中更明显。暴露于25μg/L的鱼体色变深，脊柱出现轻度弯曲。未观察到对VTG和AChE的影响，但在暴露于25μg IVM/L的鱼中观察到CAT和GST水平降低，尽管这些变化可能仅反映了在此浓度下鱼的整体状况受到了显著损害。尽管预测的IVM环境浓度低于0.25μg/L，但行为影响可能会转化为重要的生态影响，例如在捕食者-猎物相互作用中，鱼类的竞争优势可能会降低。未来的工作应解决行为破坏与种群适应性之间的联系。本研究基于单实验和多终点（锚定）方法，使结果能够整合并联系起来，以实现机理理解。
