Project description:Rationale Microplastics are a pressing global concern and inhalation of microplastic fibers has been associated with interstitial and bronchial inflammation in flock workers. However, how microplastic fibers affect the lungs is unknown. Objectives Our aim was to assess the effects of 12x31 µm nylon 6,6 (nylon) and 15x52 µm polyethylene terephthalate (polyester) textile microplastic fibers on lung epithelial growth and differentiation. Methods We used human and murine alveolar and airway-type organoids as well as air-liquid interface cultures derived from primary lung epithelial progenitor cells and incubated these with either nylon or polyester fibers or nylon leachate. In addition, mice received one dose of nylon fibers or nylon leachate and 7 days later organoid-forming capacity of isolated epithelial cells was investigated. Results We observed that nylon microfibers, more than polyester, inhibited developing airway organoids and not established ones. This effect was mediated by components leaching from nylon. Epithelial cells isolated from mice exposed to nylon fibers or leachate, also formed fewer airway organoids, suggesting long-lasting effects of nylon components on epithelial cells. Part of these effects were recapitulated in human air-liquid interface cultures. Transcriptome analysis revealed upregulation of Hoxa5 post-exposure to nylon fibers. Inhibiting Hoxa5 protein during nylon exposure restored airway organoid formation, confirming Hoxa5's pivotal role in the effects of nylon. Conclusions These results suggest that components leaching from nylon 6,6 may especially harm developing airways and/or airways undergoing repair and we strongly encourage to characterize both hazard of and exposure to microplastic fibers in more detail.
Project description:The freshwater mussel Dreissena bugensis was exposed for nine days to different microplastic particles, in detail, to three petroleum-based polymers (polyamide (PA), polyethylene terephthalate (PET), polystyrene (PS)), to one bio-based polymer (polylactic acid (PLA)) and to ground mussel shells (MS), serving as a natural particle control (size range: 20-75 µm;1000 p ml-1). Behavior endpoints were analyzed with hall sensor based real-time valvometry. Additionally, biochemical alterations of ROS detoxifying enzymes were analyzed, and a proteomic profiling on digestive gland tissue was performed.
