Saenen Nelly D, Witters Margo S, Hantoro Inneke, Tejeda Inés, Ethirajan Anitha, Van Belleghem Frank, Smeets Karen
Centre for Environmental Sciences, Hasselt University, Agoralaan Building D, 3590 Diepenbeek, Belgium.
Food Technology Department, Soegijapranata Catholic University, Jl. Pawiyatan Luhur IV/1, Bendan Duwur, Semarang 50234, Indonesia.
Antioxidants (Basel). 2023 Mar 17;12(3):739. doi: 10.3390/antiox12030739.
Currently, we lack crucial knowledge on how the physicochemical properties of particles affect cellular health, resulting in an important gap in our understanding of the human toxicity of microplastics (MPs). Our aim was to evaluate the impact of the size and the shape of MPs on uptake and the intracellular effects in a human epithelial colorectal adenocarcinoma (Caco-2) cell line. Spherical (200 nm and 2 µm) and fibre-/fragment-shaped (8.9 ± 10.1 µm by 1.14 ± 0.97 µm) polystyrene microplastics (PS-MPs) were used to study their uptake and the potential to induce redox and mitochondrial stress responses after 24 h of exposure. We demonstrated the cellular uptake of both spherical and fibre-/fragment-shaped MPs in a size-dependent manner. In response to 2 µm spheres, we observed differential expressions of redox-related genes, including , , and . All PS-MPs decreased the intracellular HO levels, which can be attributed to mitochondrial stress responses, such as increased mitochondrial DNA content, footprint, and morphology. Altogether, we demonstrated uptakes and changes in redox and mitochondrial parameters for all PS-MPs, with the 200 nm spheres showing the most profound effects. This suggests that the induction of defensive responses in Caco-2 cells mainly correlates with the number of particles taken up.
目前，我们缺乏关于颗粒的物理化学性质如何影响细胞健康的关键知识，这导致我们在理解微塑料（MPs）对人类的毒性方面存在重要差距。我们的目的是评估MPs的大小和形状对人上皮结直肠癌（Caco-2）细胞系的摄取及细胞内效应的影响。使用球形（200 nm和2 µm）以及纤维/碎片状（长8.9 ± 10.1 µm，宽1.14 ± 0.97 µm）的聚苯乙烯微塑料（PS-MPs）来研究其摄取情况以及暴露24小时后诱导氧化还原和线粒体应激反应的潜力。我们证明了球形和纤维/碎片状MPs均以大小依赖的方式被细胞摄取。对于2 µm的球体，我们观察到了氧化还原相关基因的差异表达，包括 、 和 。所有PS-MPs均降低了细胞内的HO水平，这可归因于线粒体应激反应，如线粒体DNA含量、足迹和形态的增加。总之，我们证明了所有PS-MPs的摄取情况以及氧化还原和线粒体参数的变化，其中直径200 nm的球体显示出最显著的影响。这表明在Caco-2细胞中诱导的防御反应主要与摄取的颗粒数量相关。
