Trevisan Rafael, Flores-Nunes Fabrício, Dolores Euler S, Mattos Jacó J, Piazza Clei E, Sasaki Sílvio T, Taniguchi Satie, Montone Rosalinda C, Bícego Márcia C, Dos Reis Isis M M, Zacchi Flávia L, Othero Bárbara N M, Bastolla Camila L V, Mello Danielle F, Fraga Ana Paula M, Wendt Nestor, Toledo-Silva Guilherme, Razzera Guilherme, Dafre Alcir L, de Melo Cláudio M R, Bianchini Adalto, Marques Maria R F, Bainy Afonso C D
Department of Aquaculture, Federal University of Santa Catarina, Florianópolis, Brazil.
Department of Biochemistry, Federal University of Santa Catarina, Florianópolis, Brazil.
Environ Toxicol Chem. 2017 Jul;36(7):1833-1845. doi: 10.1002/etc.3543. Epub 2016 Aug 12.
Urban sewage is a concerning issue worldwide, threatening both wildlife and human health. The present study investigated protein oxidation in mangrove oysters (Crassostrea brasiliana) exposed to seawater from Balneário Camboriú, an important tourist destination in Brazil that is affected by urban sewage. Oysters were exposed for 24 h to seawater collected close to the Camboriú River (CAM1) or 1 km away (CAM2). Seawater from an aquaculture laboratory was used as a reference. Local sewage input was marked by higher levels of coliforms, nitrogen, and phosphorus in seawater, as well as polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), linear alkylbenzenes (LABs), and fecal steroid in sediments at CAM1. Exposure of oysters to CAM1 caused marked bioaccumulation of LABs and decreased PAH and PCB concentrations after exposure to both CAM1 and CAM2. Protein thiol oxidation in gills, digestive gland, and hemolymph was evaluated. Lower levels of reduced protein thiols were detected in hemolymph from CAM1, and actin, segon, and dominin were identified as targets of protein thiol oxidation. Dominin susceptibility to oxidation was confirmed in vitro by exposure to peroxides and hypochlorous acid, and 2 cysteine residues were identified as potential sites of oxidation. Overall, these data indicate that urban sewage contamination in local waters has a toxic potential and that protein thiol oxidation in hemolymph could be a useful biomarker of oxidative stress in bivalves exposed to contaminants. Environ Toxicol Chem 2017;36:1833-1845. © 2016 SETAC.
城市污水是一个全球关注的问题，对野生动物和人类健康都构成威胁。本研究调查了暴露于巴西重要旅游目的地巴拉那瓜里乌市受城市污水影响的海水中的巴西红树林牡蛎（巴西蚶）的蛋白质氧化情况。牡蛎被暴露于靠近坎波里乌河采集的海水（CAM1）或1公里外的海水（CAM2）中24小时。来自水产养殖实验室的海水用作对照。当地污水排放的特征是海水中大肠菌群、氮和磷含量较高，以及CAM1沉积物中的多环芳烃（PAHs）、多氯联苯（PCBs）、直链烷基苯（LABs）和粪便类固醇。牡蛎暴露于CAM1导致LABs显著生物累积，并且在暴露于CAM1和CAM2后PAH和PCB浓度降低。对鳃、消化腺和血淋巴中的蛋白质巯基氧化进行了评估。在来自CAM1的血淋巴中检测到较低水平的还原型蛋白质巯基，并且肌动蛋白、丝氨酸蛋白酶抑制剂和dominin被鉴定为蛋白质巯基氧化的靶点。通过暴露于过氧化物和次氯酸在体外证实了dominin对氧化的敏感性，并且鉴定出2个半胱氨酸残基为潜在的氧化位点。总体而言，这些数据表明当地水域的城市污水污染具有潜在毒性，并且血淋巴中的蛋白质巯基氧化可能是暴露于污染物的双壳贝类氧化应激的有用生物标志物。《环境毒理学与化学》2017年；36:1833 - 1845。© 2016 SETAC。
