Griffith School of Environment and Science and the Australian Rivers Institute, Griffith University, Gold Coast Campus, QLD, 4222, Australia.
Department of Environment and Science, Queensland Government, Ecosciences Precinct, Dutton Park QLD, 4102, Australia.
Environ Res. 2023 Jan 1;216(Pt 1):114352. doi: 10.1016/j.envres.2022.114352. Epub 2022 Sep 20.
All seven species of sea turtle are facing increasing pressures from human activities that are impacting their health. Changes in circulating blood proteins of an individual, or all members of a population, can provide an early indicator of adverse health outcomes. Non-targeted measurement of all detectable proteins in a blood sample can indicate physiological changes. In the context of wildlife toxicology, this technique can provide a powerful tool for discovering biomarkers of chemical exposure and effect. This study presents a non-targeted examination of the protein abundance in sea turtle plasma obtained from three geographically distinct foraging populations of green turtles (Chelonia mydas) on the Queensland coast. Relative changes in protein expression between sites were compared, and potential markers of contaminant exposure were investigated. Blood plasma protein profiles were distinct between populations, with 85 out of the 116 identified proteins differentially expressed (p < 0.001). The most strongly dysregulated proteins were predominantly acute phase proteins, suggestive of differing immune status between the populations. The highest upregulation of known markers of immunotoxicity, such as pentraxin fusion and complement factor h, was observed in the Moreton Bay turtles. Forty-five different organohalogens were also measured in green turtle plasma samples as exposure to some organohalogens (e.g., polychlorinated biphenyls) has previously been identified as a cause for immune dysregulation in marine animals. The few detected organohalogens were at very low (pg/mL) concentrations in turtles from all sites, and are unlikely to be the cause of the proteome differences observed. However, the changes in protein expression may be indicative of exposure to other chemicals or environmental stressors. The results of this study provide important information about differences in protein expression between different populations of turtles, and guide future toxicological and health studies on east-Australian green sea turtles.
所有七种海龟都面临着来自人类活动的日益增加的压力，这些压力正在影响它们的健康。个体或所有种群的循环血液蛋白的变化可以提供不良健康结果的早期指标。非靶向性测量血液样本中所有可检测的蛋白质可以指示生理变化。在野生动物毒理学中，该技术可以为发现化学暴露和效应的生物标志物提供强大的工具。本研究对来自昆士兰海岸三个地理位置不同的觅食绿海龟（Chelonia mydas）种群的海龟血浆中的蛋白质丰度进行了非靶向性检查。比较了不同地点之间蛋白质表达的相对变化，并研究了潜在的污染物暴露标志物。种群之间的血液血浆蛋白谱明显不同，有 116 种鉴定出的蛋白质中有 85 种表达差异（p<0.001）。最强烈失调的蛋白质主要是急性期蛋白，提示种群之间的免疫状态不同。在莫顿湾海龟中观察到免疫毒性的已知标志物（如 pentraxin 融合蛋白和补体因子 h）的上调幅度最高。还在绿海龟血浆样本中测量了 45 种不同的有机卤化物，因为先前已经确定一些有机卤化物（如多氯联苯）的暴露是海洋动物免疫失调的原因。在所有地点的海龟中，检测到的有机卤化物数量非常少（pg/mL），不太可能是观察到的蛋白质组差异的原因。然而，蛋白质表达的变化可能表明暴露于其他化学物质或环境胁迫剂。本研究的结果提供了有关不同种群海龟之间蛋白质表达差异的重要信息，并指导了未来对东澳大利亚绿海龟的毒理学和健康研究。
