Location: Food Animal Metabolism Research
Title: Effect of polystyrene micro/nanoplastic size and surface functionalization on uptake and viability of gastric cellsAuthor
Banerjee, Amrita | |
Billey, Lloyd | |
Shelver, Weilin |
Submitted to: Society of Environmental Toxicology and Chemistry (SETAC)
Publication Type: Abstract Only Publication Acceptance Date: 9/1/2021 Publication Date: 11/18/2021 Citation: Banerjee, A., Billey, L.O., Shelver, W.L. 2021. Effect of polystyrene micro/nanoplastic size and surface functionalization on uptake and viability of gastric cells. Society of Environmental Toxicology and Chemistry Abstracts. Abstract. Interpretive Summary: Technical Abstract: Micro/nanoplastics (MP/NP) pollution in the environment is ubiquitous. These anthropogenic pollutants have been detected in human food and beverages, but safety information of MP/NP contaminated food is scarce. To understand the consequences of oral exposure to MP/NP, the uptake and toxicity of these particles were studied in SNU-1 human gastric cells using 50, 100, 200, 500, 1000 or 5000 nm sized and surface functionalized (animated, carboxylated) or non-functionalized polystyrene particles, as model MP/NP. Cellular uptake of 50 nm particles after 4 h treatment, was significantly higher than 1000 nm particles (p < 0.001), regardless of surface functionalization, as determined using flow cytometry and confocal laser scanning microscopy. Among the 50 nm particles, aminated beads localized in or around plasma membrane and were taken up significantly more (14% of total dose) than carboxylated (5.4%) or non-functionalized particles (4.7%) (p < 0.001). Moreover, cellular viability studies performed using alamarBlue® assay indicated that the 50 nm aminated particles were cytotoxic at a lower concentration (=7.5 µg/mL) than other particles (=10 µg/mL). After 4 h treatment, the intracellular pool of Caspase-8 (an indicator of early apoptosis) was significantly higher in cells treated with 5000 nm particles compared to cells treated with same surface functionalized 50 – 200 nm particles (p < 0.05). However, 50 nm particles induced a significantly higher proportion of cells to undergo late stage apoptosis and necrosis in 4 h compared to 1000 and 5000 nm particles, as determined by the Annexin V – propidium iodide apoptosis-necrosis assay (p < 0.01). As observed with cellular uptake and viability studies, the 50 nm aminated particles, caused significantly higher percentage of cells to undergo apoptosis-necrosis (29.2%) compared to 50 nm carboxylated (16.8%) or non-functionalized particles (14%) (p < 0.01). Overall, uptake and toxicity of polystyrene particles were highest for 50 nm, especially amine surface functionalized particles. This study demonstrated that polystyrene MP/NP can be toxic to gastric cells, which is particle size, dose and surface functionalization dependent. |