Optical Bioimaging Laboratory, Department of Biomedical Engineering, College of Design and Engineering, National University of Singapore, Singapore 117576, Singapore.
School of Electronic Information and Electrical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
Environ Int. 2024 May;187:108679. doi: 10.1016/j.envint.2024.108679. Epub 2024 Apr 20.
Microplastics (MP) and nanoplastics (NP) pollutions pose a rising environmental threat to humans and other living species, given their escalating presence in essential resources that living subjects ingest and/or inhale. Herein, to elucidate the potential health implications of MP/NP, we report for the first time by using label-free hyperspectral stimulated Raman scattering (SRS) imaging technique developed to quantitatively monitor the bioaccumulation and metabolic toxicity of MP/NP within live zebrafish larvae during their early developmental stages. Zebrafish embryos are exposed to environmentally related concentrations (3-60 μg/ml) of polystyrene (PS) beads with two typical sizes (2 μm and 50 nm). Zebrafish are administered isotope-tagged fatty acids through microinjection and dietary intake for in vivo tracking of lipid metabolism dynamics. In vivo 3D quantitative vibrational imaging of PS beads and intrinsic biomolecules across key zebrafish organs reveals that gut and liver are the primary target organs of MP/NP, while only 50 nm PS beads readily aggregate and adhere to the brain and blood vessels. The 50 nm PS beads are also found to induce more pronounced hepatic inflammatory response compared to 2 μm counterparts, characterized by increased biogenesis of lipid droplets and upregulation of arachidonic acid detected in zebrafish liver. Furthermore, Raman-tagged SRS imaging of fatty acids uncovers that MP/NP exposure significantly reduces yolk lipid utilization and promotes dietary lipid storage in zebrafish, possibly associated with developmental delays and more pronounced food dilution effects in zebrafish larvae exposed to 2 μm PS beads. The hyperspectral SRS imaging in this work shows that MP/NP exposure perturbs the development and lipid metabolism in zebrafish larvae, furthering the understanding of MP/NP ingestions and consequent toxicity in different organs in living species.
微塑料（MP）和纳米塑料（NP）污染对人类和其他生物物种构成了日益严重的环境威胁，因为它们在生物摄取和/或吸入的基本资源中的存在不断增加。在此，为了阐明 MP/NP 的潜在健康影响，我们首次使用无标记的高光谱受激拉曼散射（SRS）成像技术报告，该技术旨在定量监测 MP/NP 在活体斑马鱼幼虫早期发育阶段的生物积累和代谢毒性。将斑马鱼胚胎暴露于环境相关浓度（3-60μg/ml）的两种典型尺寸（2μm和50nm）的聚苯乙烯（PS）珠中。通过微注射和饮食摄入向斑马鱼给予同位素标记的脂肪酸，以进行体内脂质代谢动力学的追踪。PS 珠和内在生物分子在关键斑马鱼器官中的体内 3D 定量振动成像表明，肠道和肝脏是 MP/NP 的主要靶器官，而只有 50nm PS 珠容易聚集并粘附在大脑和血管上。与 2μm PS 珠相比，还发现 50nm PS 珠诱导更明显的肝炎症反应，其特征是脂质滴的生物发生增加和检测到的花生四烯酸在斑马鱼肝脏中的上调。此外，脂肪酸的拉曼标记 SRS 成像揭示，MP/NP 暴露显著降低了蛋黄脂质的利用，并促进了斑马鱼的饮食脂质储存，这可能与暴露于 2μm PS 珠的斑马鱼幼虫的发育延迟和更明显的食物稀释效应有关。本工作中的高光谱 SRS 成像表明，MP/NP 暴露会干扰斑马鱼幼虫的发育和脂质代谢，进一步了解不同物种中 MP/NP 的摄取和随之而来的毒性。
