Ragusa Maria Antonietta, Costa Salvatore, Cuttitta Angela, Gianguzza Fabrizio, Nicosia Aldo
Department of Biological, Chemical, and Pharmaceutical Sciences and Technologies, University of Palermo, viale delle Scienze, Ed. 16, 90128, Palermo, Sicily, Italy.
National Research Council-Institute for Marine and Coastal Environment (IAMC-CNR), Laboratory of Molecular Ecology and Biotechnology, Detached Unit of Capo Granitola, Torretta Granitola, Trapani, Sicily, Italy.
Chemosphere. 2017 Aug;180:275-284. doi: 10.1016/j.chemosphere.2017.04.030. Epub 2017 Apr 10.
Among sulfonamides, sulfamethoxazole represents one of the most widely employed. A considerable amount of sulfamethoxazole is introduced into the marine environment after utilization in aquaculture. The cytotoxicity of sulfamethoxazole relies mainly on arylhydroxylamine metabolites and it is associated with the production of reactive oxygen species. Cadmium represents a metal largely employed in several anthropic activities and it is toxic for all living organisms even at low concentrations. Since it is not degraded, cadmium irreversibly accumulates into cells. In order to understand the mechanisms of response to changes in the chemical environment, we investigated by light microscopy observations and RT-qPCR assays the impact of sulfamethoxazole and cadmium in P. lividus sea urchin embryos. During development, embryos were exposed to sulfamethoxazole amount comparable to that usually used in aquaculture procedures and/or sublethal levels of cadmium chloride. Impairment of development and biomarkers for inflammation, detoxification, metal scavenging and cell death were inspected. Even though treatment with sulfamethoxazole apparently did not affect development, it stimulated a remarkable molecular response to oxidative stress. Moreover, combined exposure seriously compromised development and the defense mechanisms to cadmium were blocked. This study leads to the conclusion that coexposure to sulfamethoxazole and cadmium induces neutralizing effects on sea urchin embryos. Thus, in marine areas nearby aquaculture farms, where sulfamethoxazole discharge represents an important environmental contaminant, cadmium occurrence may alter population dynamics of P. lividus.
在磺胺类药物中，磺胺甲恶唑是应用最为广泛的药物之一。大量磺胺甲恶唑在水产养殖中使用后被引入海洋环境。磺胺甲恶唑的细胞毒性主要依赖于芳基羟胺代谢物，并且与活性氧的产生有关。镉是一种在多种人类活动中大量使用的金属，即使在低浓度下对所有生物也具有毒性。由于镉不会降解，它会不可逆地在细胞中积累。为了了解对化学环境变化的响应机制，我们通过光学显微镜观察和RT-qPCR分析研究了磺胺甲恶唑和镉对紫海胆胚胎的影响。在发育过程中，胚胎暴露于与水产养殖程序中通常使用的量相当的磺胺甲恶唑和/或亚致死水平的氯化镉中。检查了发育受损情况以及炎症、解毒、金属清除和细胞死亡的生物标志物。尽管用磺胺甲恶唑处理显然没有影响发育，但它刺激了对氧化应激的显著分子反应。此外，联合暴露严重损害了发育，并且对镉的防御机制被阻断。这项研究得出的结论是，磺胺甲恶唑和镉的共同暴露对海胆胚胎产生中和作用。因此，在水产养殖场附近的海域，磺胺甲恶唑排放是一种重要的环境污染物，镉的存在可能会改变紫海胆的种群动态。
