Lu Jie, Yao Tuo, Yu Gang, Ye Lingtong
Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, China.
Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, China.
Sci Total Environ. 2023 Dec 15;904:166277. doi: 10.1016/j.scitotenv.2023.166277. Epub 2023 Aug 14.
Zinc Oxide nanoparticles (ZnO NPs), due to their ubiquitous use in industrial and consumer applications, present potential risks to marine ecosystems and biota, especially oysters. The physiological and immunological health of marine species is highly dependent on salinity levels. However, the combined impact of lowered salinity and exposure to ZnO NPs, particularly on key marine species like oysters, is an area that requires more research. Our study aimed to examine these concurrent stressors' impacts on phenotypic markers, gill and hepatopancreas physiological indices, and hemocyte immune parameters of Crassostrea hongkongensis. We subjected six oyster cohorts to varied ZnO NPs concentrations and salinity levels over 21 days. Our findings reveal that individual exposure to ZnO NPs or diminished salinity disrupts oyster physiology, impacting metabolism, antioxidant capacity, immune response, and energy distribution through distinct mechanisms. Remarkably, low salinity constituted a more significant threat than isolated ZnO NPs. However, when confronted with combined stressors, oysters exhibited a compensatory response, attenuating individual stressors' detrimental effects. This adaptation was characterised by reduced apoptosis rates, increased calcium ion concentration in mature hemocytes, and a restoration of conditioned indices, hepatopancreas alkaline phosphatase, and gill catalase activity to baseline levels. Principal Component Analysis and Integrated Biomarker Responses validated this compensatory phenomenon. Partial Least Squares Pathway Model analysis underscored these stressors' profound implications on oyster health, primarily driven by stressor exposure rather than mere zinc concentrations, despite acknowledging zinc's immunosuppressive impact on oyster immunity. Our research emphasises the importance of assessing multiple stressors' cumulative effects on aquatic species' ecological resilience, accentuating the need for comprehensive analyses incorporating functional specificity among diverse organs and immune components, including gill, hepatopancreas, and the critical hemocytes.
氧化锌纳米颗粒（ZnO NPs）因其在工业和消费应用中的广泛使用，对海洋生态系统和生物群，尤其是牡蛎，存在潜在风险。海洋物种的生理和免疫健康高度依赖于盐度水平。然而，盐度降低和接触ZnO NPs的综合影响，特别是对牡蛎等关键海洋物种的影响，是一个需要更多研究的领域。我们的研究旨在考察这些同时存在的应激源对香港巨牡蛎的表型标记、鳃和肝胰腺生理指标以及血细胞免疫参数的影响。我们将六个牡蛎组在21天内暴露于不同浓度的ZnO NPs和盐度水平下。我们的研究结果表明，单独暴露于ZnO NPs或盐度降低都会扰乱牡蛎的生理机能，通过不同机制影响新陈代谢、抗氧化能力、免疫反应和能量分配。值得注意的是，低盐度构成的威胁比单独的ZnO NPs更大。然而，当面对复合应激源时，牡蛎表现出一种补偿反应，减轻了单个应激源的有害影响。这种适应性表现为凋亡率降低、成熟血细胞中钙离子浓度增加，以及条件指数、肝胰腺碱性磷酸酶和鳃过氧化氢酶活性恢复到基线水平。主成分分析和综合生物标志物反应验证了这种补偿现象。偏最小二乘路径模型分析强调了这些应激源对牡蛎健康的深远影响，尽管认识到锌对牡蛎免疫力有免疫抑制作用，但这种影响主要是由应激源暴露而非仅仅是锌浓度驱动的。我们的研究强调了评估多种应激源对水生物种生态恢复力的累积影响的重要性，突出了需要进行综合分析，纳入不同器官和免疫成分（包括鳃、肝胰腺和关键血细胞）之间的功能特异性。
