USDA-Agricultural Research Service, Edward T. Schafer Agricultural Research Center, Biosciences Research Laboratory, 1616 Albrecht Blvd N, Fargo, ND 58102, USA.
USDA-Agricultural Research Service, Edward T. Schafer Agricultural Research Center, Biosciences Research Laboratory, 1616 Albrecht Blvd N, Fargo, ND 58102, USA.
Sci Total Environ. 2022 Aug 25;836:155621. doi: 10.1016/j.scitotenv.2022.155621. Epub 2022 May 2.
Micro/nanoplastics (MP/NP) contaminate our food and drinking water but their impact on human health has not been well-documented. The liver is one of the first organs that ingested MP/NP encounter and it has a major role in the clearance of xenobiotics. Therefore, the effects of polystyrene MP/NP on liver HepG2 cells were studied. Cellular responses to particles of various sizes (50-5000 nm) and surface functionalization (aminated, carboxylated or non-functionalized) were determined at different concentrations (0.1-100 μg/mL) and exposure periods (1-24 h). Smaller sized particles were internalized by HepG2 cells more avidly than larger particles regardless of functionalization; the highest uptake being for 50 and 100 nm aminated particles at lower concentrations. Confocal microscopy images of cells corroborated quantitative uptake results. Aminated particles were more toxic to the cells than carboxylated or non-functionalized particles. Among aminated particles smaller particles (50 and 100 nm) were more detrimental to cell viability compared to larger particles (1000 or 5000 nm) with toxicity increasing with concentration. Treatment with the particles for 4 h increased intracellular concentrations of Caspase-3 by 1.5-2.8 fold, but 24 h exposure to the particles attenuated this increase in Caspase-3 concentrations. A slight trend of higher Caspase-3 concentration in cells treated with larger particles (500-5000 nm) compared to smaller particles (50-200 nm) was observed, indicating that larger particles are more likely to direct cells toward apoptotic cell death upon 4 h exposure. Exposure of cells to large PS particles (500-5000 nm) upregulated interleukin-8 and the effect was enhanced at 24 h. Overall, the study demonstrated that smaller aminated particles were most toxic to hepatocytes, but larger particles induced apoptotic cell death or an inflammatory response depending on the length of exposure.
微/纳米塑料（MP/NP）污染了我们的食物和饮用水，但它们对人类健康的影响尚未得到充分记录。肝脏是摄入 MP/NP 后首先接触到的器官之一，它在清除异源物质方面起着重要作用。因此，研究了聚苯乙烯 MP/NP 对 HepG2 细胞的肝脏的影响。在不同浓度（0.1-100 μg/mL）和暴露时间（1-24 h）下，研究了不同大小（50-5000nm）和表面功能化（氨基化、羧基化或非功能化）的颗粒对细胞的反应。无论功能化如何，较小尺寸的颗粒都比较大尺寸的颗粒更被 HepG2 细胞内化；在较低浓度下，氨基化的 50 和 100nm 颗粒的摄取量最高。细胞的共焦显微镜图像证实了定量摄取结果。氨基化颗粒比羧基化或非功能化颗粒对细胞更具毒性。在氨基化颗粒中，较小的颗粒（50 和 100nm）比较大的颗粒（1000 或 5000nm）对细胞活力更有害，毒性随浓度增加而增加。用颗粒处理 4 小时可使 Caspase-3 的细胞内浓度增加 1.5-2.8 倍，但 24 小时暴露于颗粒会降低 Caspase-3 浓度的增加。用较大颗粒（500-5000nm）处理的细胞中 Caspase-3 浓度略有升高的趋势，与较小颗粒（50-200nm）相比，这表明较大颗粒在 4 小时暴露后更有可能使细胞向凋亡性细胞死亡方向发展。细胞暴露于较大的 PS 颗粒（500-5000nm）会上调白细胞介素-8，24 小时后这种作用会增强。总的来说，该研究表明，较小的氨基化颗粒对肝细胞毒性最大，但较大的颗粒会根据暴露时间诱导凋亡性细胞死亡或炎症反应。
