Laboratory of Biomarkers of Aquatic Contamination and Immunochemistry, Department of Biochemistry, Federal University of Santa Catarina, UFSC, Florianópolis, SC, Brazil.
Aquaculture Pathology Research, NEPAQ, Federal University of Santa Catarina, Florianópolis, SC, Brazil.
Chemosphere. 2018 Oct;209:307-318. doi: 10.1016/j.chemosphere.2018.06.094. Epub 2018 Jun 15.
Exposure of aquatic organisms to polycyclic aromatic hydrocarbons (PAH), such as phenanthrene (PHE), may increase the production of reactive oxygen species (ROS) and cause changes in the biotransformation systems. In addition, changes in water temperature can cause adverse effects in the organisms. Estuarine species, like the oyster Crassostrea brasiliana, can adapt and tolerate temperature variation. To evaluate the influence of temperature on biological responses of C. brasiliana exposed to PHE, oysters were maintained at three temperatures (18, 24 and 32 °C) for 15 days and co-exposed afterwards to 100 μg.L of PHE for 24 and 96 h. Levels of PHE in the water and oyster tissues were determined, respectively after 24 and 96 h. In addition, thermal stress, biotransformation and oxidative stress-related genes were analyzed in oyster gills, together with the activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferases (GST) and levels of lipid peroxidation. Oyster accumulated significant levels of PHE. HSP70-like transcripts were affected by PHE exposure only at 32 °C. Transcript levels of cytochrome P450 isoforms (CYP2-like2 and CYP2AU1) were down-regulated in oysters exposed to PHE for 24 h at 32 °C. GSTΩ-like transcript levels were also down-regulated in the PHE-exposed group at 32 °C. After 96 h, CYP2-like2 transcripts were higher in the PHE exposed groups at 32 °C. Oysters kept at 18 °C showed higher levels of SOD-like transcripts, together with higher GST, GPx and G6PDH activities, associated to lower levels of lipoperoxidation. In general the biological responses evaluated were more affected by temperature, than by co-exposure to PHE.
水生生物暴露于多环芳烃（PAH），如菲（PHE），可能会增加活性氧（ROS）的产生，并导致生物转化系统的变化。此外，水温的变化会对生物产生不利影响。河口物种，如牡蛎 Crassostrea brasiliana，可以适应和耐受温度变化。为了评估温度对暴露于 PHE 的 C. brasiliana 生物反应的影响，将牡蛎分别在 18、24 和 32°C 下维持 15 天，然后在 24 和 96 小时后暴露于 100μg.L 的 PHE。在 24 和 96 小时后分别测定水中和牡蛎组织中的 PHE 水平。此外，还分析了牡蛎鳃中与热应激、生物转化和氧化应激相关的基因，以及超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、谷胱甘肽过氧化物酶（GPx）、谷胱甘肽-S-转移酶（GST）的活性和脂质过氧化水平。牡蛎积累了显著水平的 PHE。HSP70 样转录物仅在 32°C 下受到 PHE 暴露的影响。在 32°C 下，暴露于 PHE 24 小时的 CYP2 样 2 和 CYP2AU1 同工型的细胞色素 P450 转录物水平下调。在 32°C 下，暴露于 PHE 的 GSTΩ 样转录物水平也下调。96 小时后，在 32°C 下暴露于 PHE 的组中 CYP2 样 2 转录物水平较高。在 18°C 下保存的牡蛎显示出更高水平的 SOD 样转录物，同时具有更高的 GST、GPx 和 G6PDH 活性，与更低的脂质过氧化水平相关。一般来说，与 PHE 共暴露相比，温度对评估的生物反应影响更大。
