Micro- and nano-plastics activation of oxidative and inflammatory adverse outcome pathways

Abstract

Microplastics (MPs) and nanoplastics (NPs) have attracted considerable attention in the recent years as potential threats to the ecosystem and public health. This review summarizes current knowledge of pathological events triggered by micro- and nano-plastics (MP/NPs) with focus on oxidative damages at different levels of biological complexity (molecular, cellular, tissue, organ, individual and population). Based on published information, we matched the apical toxicity endpoints induced by MP/NPs with key event (KE) or adverse outcomes (AO) and categorized them according to the Adverse Outcome Pathway (AOP) online knowledgebase. We used existing AOPs and applied them to highlight formal mechanistic links between identified KEs and AOs in two possible scenarios: first from ecological, and second from public health perspective. Ecological perspective AOP based literature analysis revealed that MP/NPs share formation of reactive oxygen species as their molecular initiating event, leading to adverse outcomes such as growth inhibition and behavior alteration through oxidative stress cascades and inflammatory responses. Application of AOP on literature data related to public health perspective of MP/NPs showed that oxidative stress and its responding pathways, including inflammatory responses, could play the role of key events. However insufficient information prevented precise definitions of AOPs at this level. To overcome this knowledge gap, further mammalian model and epidemiological studies are necessary to support development and construction of detailed AOPs with public health focus.

Stress Response of Mouse Embryonic Fibroblasts Exposed to Polystyrene Nanoplastics

“…When PS nanoplastics are in endosomes, they can be released into the cytoplasm by endosomal escape. PS nanoplastics in the cytoplasm can interfere with normal cellular function, putting cells under stress conditions such as oxidative or inflammatory stress [ 6 ]. Alternatively, PS nanoplastic-containing (PS-containing) endosomes can be fused with lysosomes, but it is unlikely that PS nanoplastics are degraded in the lysosomal compartment.…”

Lung organoids and microplastic fibers: a new exposure model for emerging contaminants

“…To investigate the possible changes in the inflammatory cytokine expression in hAOs after MPF exposure, gene expression analysis by qRT-PCR was performed as described above at the end of the coculture with the highest MPF concentration using the primers listed in Table S2. Considering that the exposure of MPFs could induce oxidative stress in human tissues (Hu and Palić 2020), we analyzed the expression of genes involved in oxidative stress pathways reported in relation to MPF exposure, including superoxide dismutase family genes (SOD1 and SOD2), glutathione detox-related genes (GSTA1 and GPX1), catalase (CAT), and ROS-controlling genes (NOX2, COX1, and ND1). In addition, the capacity of our 3D structures to respond to standard inflammatory stimuli was evaluated after treatment with poly(I:C) (50 μg mL −1 ) as a positive control.…”

Microplastics: A Threat for Male Fertility

“…Based on the trends of that period, the researchers estimated that by 2050 the amount of plastic waste in landfills and the environment would reach 12,000 million tons. Nonetheless, the potential dangers of escalating plastics pollution, particularly MPs pollution, have remained largely ignored by governments and policy makers [ 15 , 16 ].…”