Mognetti Barbara, Cecone Claudio, Fancello Katia, Saraceni Astrid, Cottone Erika, Bovolin Patrizia
Department of Life Sciences and Systems Biology, University of Turin, Via Accademia Albertina 13, 10123 Turin, Italy.
SUSPLAS@UniTo, Sustainable Plastic Scientific Hub, University of Turin, 10100 Turin, Italy.
Int J Mol Sci. 2025 Mar 22;26(7):2899. doi: 10.3390/ijms26072899.
The inevitable exposure of humans to micro/nanoplastics has become a pressing global environmental issue, with growing concerns regarding their impact on health. While the direct effects of micro/nanoplastics on human health remain largely unknown, increasing attention is being given to their potential role as carriers of environmental pollutants and organic substances. This study investigates the direct toxicity of 500 nm polystyrene nanoplastics (NPs) on human hepatocytes (HepG2) in vitro, both alone and in combination with cadmium (Cd), a hazardous heavy metal and a prevalent environmental pollutant. One-hour exposure to 100 µg/mL of NPs causes a significant increase in ROS production (+25% compared to control) but cell viability remains unaffected even at concentrations much higher than environmental levels. Interestingly, NPs significantly reduce Cd cytotoxicity at LC concentrations (cell viability compared to control: 55.4% for 50 µM Cd, 66.9% for 50 µM Cd + 10 µg/mL NPs, 68.4% for 50 µM Cd + 100 µg/mL NPs). Additionally, NPs do not alter the cellular lipid content after short-term exposure (24 h). However, when Cd and fatty acids are added to the medium, NPs appear to sequester fatty acids, reducing their availability and impairing their uptake by cells in a dose-dependent manner. We confirmed by Dynamic Light Scattering and Scanning Electron Microscopy the interaction between NPs, Cd and free fatty acids. Although polystyrene NPs exhibited minimal cytotoxicity in our experimental model, collectively our findings suggest that predicting the effects of cell exposure to NPs is extremely challenging, due to the potential interaction between NPs, environmental pollutants and specific components of the biological matrix.
人类不可避免地接触到微塑料/纳米塑料已成为一个紧迫的全球环境问题，人们越来越关注它们对健康的影响。虽然微塑料/纳米塑料对人类健康的直接影响在很大程度上仍不为人知，但它们作为环境污染物和有机物质载体的潜在作用正受到越来越多的关注。本研究调查了500纳米聚苯乙烯纳米塑料（NPs）对人肝细胞（HepG2）的体外直接毒性，包括单独作用以及与镉（Cd）联合作用，镉是一种有害重金属和普遍存在的环境污染物。暴露于100µg/mL的NPs 1小时会导致活性氧生成显著增加（与对照组相比增加25%），但即使在远高于环境水平的浓度下，细胞活力仍未受影响。有趣的是，在LC浓度下，NPs能显著降低镉的细胞毒性（与对照组相比的细胞活力：50µM镉为55.4%，50µM镉 + 10µg/mL NPs为66.9%，50µM镉 + 100µg/mL NPs为68.4%）。此外，短期暴露（24小时）后，NPs不会改变细胞脂质含量。然而，当向培养基中添加镉和脂肪酸时，NPs似乎会螯合脂肪酸，以剂量依赖的方式降低其可用性并损害细胞对其的摄取。我们通过动态光散射和扫描电子显微镜证实了NPs、镉和游离脂肪酸之间的相互作用。尽管聚苯乙烯NPs在我们的实验模型中表现出最小的细胞毒性，但总体而言，我们的研究结果表明，由于NPs、环境污染物和生物基质的特定成分之间可能存在相互作用，预测细胞暴露于NPs的影响极具挑战性。
