Department of Rheumatology and Immunology, The First People's Hospital of Changzhou (The Third Affiliated Hospital of Soochow University), Changzhou, 213003, China.
School of Pharmacy, Changzhou University, Changzhou, 213164, China.
Sci Rep. 2024 Jul 15;14(1):16329. doi: 10.1038/s41598-024-67289-y.
Microplastics (MPs) are defined as plastic particles smaller than 5 mm in size, and nanoplastics (NPs) are those MPs with a particle size of less than 1000 nm or 100 nm. The prevalence of MPs in the environment and human tissues has raised concerns about their potential negative effects on human health. Macrophages are the major defence against foreign substances in the intestine, and can be polarized into two types: the M1 phenotype and the M2 phenotype. However, the effect of NPs on the polarization of macrophages remains unclear. Herein, we selected polystyrene, one of the most plastics in the environment and controlled the particle sizes at 50 nm and 500 nm respectively to study the effects on the polarization of macrophages. We used mouse RAW264.7 cell line models in this macrophage-associated study. Experiments on cell absorption showed that macrophages could quickly ingest polystyrene nanoplastics of both diameters with time-dependent uptake. Compared to the untreated group and 10 μg/mL treatment group, macrophages exposed to 50 μg/mL groups (50 nm and 500 nm) had considerably higher levels of CD86, iNOS, and TNF-α, but decreased levels of aCD206, IL-10, and Arg-1. According to these findings, macrophage M1 and M2 polarization can both be induced and inhibited by 50 μg/mL 50 nm and 500 nm polystyrene nanoplastics. This work provided the first evidence of a possible MPs mode of action with appropriate concentration and size through the production of polarized M1, providing dietary and environmental recommendations for people, particularly those with autoimmune and autoinflammatory illnesses.
微塑料（MPs）被定义为粒径小于 5 毫米的塑料颗粒，而纳米塑料（NPs）则是粒径小于 1000 纳米或 100 纳米的 MPs。MPs 在环境和人体组织中的普遍存在引起了人们对其对人类健康潜在负面影响的关注。巨噬细胞是肠道中抵御外来物质的主要防御细胞，可以极化为两种类型：M1 表型和 M2 表型。然而，NPs 对巨噬细胞极化的影响尚不清楚。在此，我们选择了聚苯乙烯作为环境中最常见的塑料之一，并分别将粒径控制在 50nm 和 500nm，以研究其对巨噬细胞极化的影响。我们使用了小鼠 RAW264.7 细胞系模型进行这项与巨噬细胞相关的研究。细胞摄取实验表明，巨噬细胞可以快速摄取两种直径的聚苯乙烯纳米塑料，并随着时间的推移呈时间依赖性摄取。与未经处理组和 10μg/mL 处理组相比，暴露于 50μg/mL 组（50nm 和 500nm）的巨噬细胞中 CD86、iNOS 和 TNF-α 的水平显著升高，而 aCD206、IL-10 和 Arg-1 的水平则降低。根据这些发现，50μg/mL 的 50nm 和 500nm 聚苯乙烯纳米塑料可以诱导和抑制巨噬细胞 M1 和 M2 极化。这项工作首次提供了通过产生极化的 M1 来介导 MPs 作用模式的证据，为人们，特别是患有自身免疫和自身炎症性疾病的人们提供了饮食和环境方面的建议。
