Centro de Investigación Esquel de Montaña y Estepa Patagónica (CIEMEP), CONICET-UNPSJB, Roca 780, 9200 Esquel, Argentina; Facultad de Ciencias Naturales y Ciencias de la Salud, Universidad Nacional de la Patagonia San Juan Bosco (UNPSJB), 9200 Esquel, Chubut, Argentina.
Centro de Investigación Esquel de Montaña y Estepa Patagónica (CIEMEP), CONICET-UNPSJB, Roca 780, 9200 Esquel, Argentina; Facultad de Ciencias Naturales y Ciencias de la Salud, Universidad Nacional de la Patagonia San Juan Bosco (UNPSJB), 9200 Esquel, Chubut, Argentina.
Comp Biochem Physiol C Toxicol Pharmacol. 2019 Mar;217:32-40. doi: 10.1016/j.cbpc.2018.11.019. Epub 2018 Nov 27.
Environmental impairment resulted from urbanizations can produce damage on freshwater species including strong physiological effects at individual or population level. The multixenobiotic resistance (MXR) is a defence mechanism which has been demonstrated in several aquatic organisms. The key mediators of MXR activity are ATP-binding cassette (ABC) proteins like P-glycoprotein (P-gp). This system protects aquatic organisms against the accumulation of xenobiotics by extruding them from cells in an energy-dependent manner. MXR has been pointed out as relevant in the ecotoxicological context and has been proposed as a biomarker for pollution assessment. Since fish species are common target in freshwater biomonitoring programs, the purpose of the study was to evaluate the MXR mechanism in native Hatcheria macraei (Patagonian catfish) and exotics Salmo trutta (brown trout), Oncorhynchus mykiss (rainbow trout) and Oncorhynchus tshawytscha (Chinook salmon) freshwater fishes widespread in Argentine Patagonia. We characterized the MXR mechanism using a combination of functional assays and Western blot analysis. Our results in different tissues such as liver, gills, muscle and epidermis indicate that the fishes studied have different species-specific levels of MXR activity, being gills and liver the tissues with greater detoxifying activity. Induction of MXR transport activity was also identified in liver tissue from rainbow trout from urban stream suggesting their suitability in the biomonitoring of aquatic environments subjected to urban contaminants.
城市化导致的环境损害会对包括淡水物种在内的生物造成损害，包括个体和种群水平的强烈生理影响。多药耐药（MXR）是一种已在几种水生生物中得到证实的防御机制。MXR 活性的关键介质是 ATP 结合盒（ABC）蛋白，如 P-糖蛋白（P-gp）。该系统通过以能量依赖的方式将外来物质从细胞中排出，从而保护水生生物免受外来物质的积累。MXR 在生态毒理学方面被认为是相关的，并已被提议作为污染评估的生物标志物。由于鱼类是淡水生物监测计划中的常见目标，因此本研究的目的是评估原生 Hatcheria macraei（巴塔哥尼亚猫鱼）和外来种 Salmo trutta（褐鳟）、Oncorhynchus mykiss（虹鳟）和 Oncorhynchus tshawytscha（奇努克鲑鱼）在阿根廷巴塔哥尼亚广泛分布的淡水鱼类中的 MXR 机制。我们使用功能测定和 Western blot 分析相结合的方法来表征 MXR 机制。我们在不同组织（如肝脏、鳃、肌肉和表皮）的研究结果表明，研究中的鱼类具有不同的物种特异性 MXR 活性水平，鳃和肝脏是具有更大解毒活性的组织。从城市溪流中的虹鳟鱼肝脏组织中也鉴定出了 MXR 转运活性的诱导，表明它们适合用于监测受到城市污染物影响的水生环境。
