Liu Yuxin, Møller Peter, Roursgaard Martin
Department of Public Health, Section of Environmental Health, University of Copenhagen, Øster Farimagsgade 5A, Copenhagen DK-1014, Denmark.
Department of Public Health, Section of Environmental Health, University of Copenhagen, Øster Farimagsgade 5A, Copenhagen DK-1014, Denmark.
Mutat Res Genet Toxicol Environ Mutagen. 2025 Apr;903:503865. doi: 10.1016/j.mrgentox.2025.503865. Epub 2025 Mar 5.
Plastic is used extensively worldwide. However, plastic particles that are less than 1000 nm (i.e. nanoplastics) may be hazardous to human cells. Nanoplastics might be manufactured intentionally or be formed in the environment by degradation of larger plastic items. Ingestion and inhalation are the two most common routes of human exposure to nanoplastics, indicating that epithelial cells have direct exposure. However, immune cells will also interact with particles during tissue inflammation. An assessment of published studies suggests that polystyrene (PS) particles generate higher levels of DNA damage in immune cells compared to epithelial cells, although it has not been formally studied under the same experimental condition. To investigate this, we assessed cytotoxicity, oxidative stress and DNA strand breaks in lung epithelial (A549) cells, intestinal epithelial (Caco-2) cells, and two monocytes (THP-1 and U937) after exposure to amine-functionalized polystyrene particles (PS-NH) with declared particle size of 240 nm. No cytotoxicity or intracellular reactive oxygen species production were found at concentrations up to 200 µg/mL. Exposure to PS-NH was associated with glutathione depletion in A549 cells. However, there was no increase in the level of DNA strand breaks, measured by the comet assay, in any of the cell lines under standard assay conditions. Diethyl maleate treatment was used to render cells susceptible to oxidative stress. By itself, diethyl maleate treatment led to approximately 50 % glutathione depletion and increased DNA strand breaks, but additional DNA damage was not observed in cells by PS-NH exposure in A549, Caco-2, THP-1 and U937 cells.
塑料在全球被广泛使用。然而，小于1000纳米的塑料颗粒（即纳米塑料）可能对人体细胞有害。纳米塑料可能是有意制造的，也可能是在环境中由较大塑料物品降解形成的。摄入和吸入是人类接触纳米塑料的两种最常见途径，这表明上皮细胞会直接接触到纳米塑料。然而，在组织炎症期间免疫细胞也会与颗粒相互作用。对已发表研究的评估表明，与上皮细胞相比，聚苯乙烯（PS）颗粒在免疫细胞中产生的DNA损伤水平更高，尽管尚未在相同实验条件下进行正式研究。为了对此进行研究，我们评估了暴露于宣称粒径为240纳米的胺功能化聚苯乙烯颗粒（PS-NH）后，肺上皮（A549）细胞、肠上皮（Caco-2）细胞以及两种单核细胞（THP-1和U937）的细胞毒性、氧化应激和DNA链断裂情况。在浓度高达200微克/毫升时未发现细胞毒性或细胞内活性氧的产生。暴露于PS-NH与A549细胞中的谷胱甘肽消耗有关。然而，在标准检测条件下，通过彗星试验测量，任何细胞系中的DNA链断裂水平均未增加。使用马来酸二乙酯处理使细胞易受氧化应激影响。马来酸二乙酯处理本身导致约50%的谷胱甘肽消耗并增加了DNA链断裂，但在A549、Caco-2、THP-1和U937细胞中，PS-NH暴露并未使细胞出现额外的DNA损伤。
