biostudies-literatureDi Cintio FNextGenerationEU35128https://www.ebi.ac.uk/biostudies/studies/S-EPMC12508049biostudies-literatureUnknown15(1)Plastics pose a significant global threat to the ecosystems due to their accumulation and impact on human health. The degradation of plastics results in the formation of microplastics (MPs), small particles less than 5 mm in size, which are released into the environment. Polystyrene (PS) is a major chemical component of plastics, and exposure to PS-based microplastics (PS-MPs) has been linked to cellular damage. This study aimed to explore the effects of 1 μm PS-MPs on human gingival fibroblast cells (hGF). PS-MPs induced a limited cytotoxicity at the tested concentrations and time points. Confocal microscopy, TEM and flow cytometry revealed the uptake of PS-MPs in about 10% of hGF cells. Proteomics identified a profoundly altered proteostasis in PS-MPs treated cells. Enrichment analysis oScientific reportsPolystyrene microplastics are internalized by human gingival fibroblasts, enhance cell motility and induce molecular changes revealed through proteomic analysis.PMC12508049ECS00000041Di Cintio FRonci MRuggieri AGDi Carlo PSallese MDe Simone CPerrotti VfalsePolystyrene microplastics are internalized by human gingival fibroblasts, enhance cell motility and induce molecular changes revealed through proteomic analysis.Plastics pose a significant global threat to the ecosystems due to their accumulation and impact on human health. The degradation of plastics results in the formation of microplastics (MPs), small particles less than 5 mm in size, which are released into the environment. Polystyrene (PS) is a major chemical component of plastics, and exposure to PS-based microplastics (PS-MPs) has been linked to cellular damage. This study aimed to explore the effects of 1 μm PS-MPs on human gingival fibroblast cells (hGF). PS-MPs induced a limited cytotoxicity at the tested concentrations and time points. Confocal microscopy, TEM and flow cytometry revealed the uptake of PS-MPs in about 10% of hGF cells. Proteomics identified a profoundly altered proteostasis in PS-MPs treated cells. Enrichment analysis o2025-01-01T00:00:00Z2025 Oct2026-06-04T09:13:28.875Z2026-05-07T03:12:53.111ZS-EPMC125080494106256010.1038/s41598-025-19064-w