Reduced cellular process and developmental process genotoxicity of polystyrene nanoplastics in zebrafish embryogenesis using Aurelia aurita proteins

The effects of polystyrene nanoplastic (PS-NP) on the human body is a matter of global concern, as they are mainly absorbed through the food chain after release into the water ecosystem. In this study, mucin (Mu) was extracted from Aurelia aurita and its effect to reduce the toxicity of PS-NP present in water was verified. However, the effect of Mu on genotoxicity was not verified. Zebrafish embryos were exposed to PS-NP, Mu, and Mu + PS-NP to verify their effects on genotoxicity. Based on the subsequent phenotypic anomalies in the juvenile fish, mRNA sequencing (mRNA-seq) was employed to determine the changes in the levels of gene transcription induced by PS-NP. Compared with the control group, the experimental group exposed to Mu or PS-NP + Mu showed no specific variations in phenotypic anomalies. In contrast, the experimental group exposed to PS-NP alone showed effects, such as pericardial edema, yolk-sac edema, thicker yolk, tail deformity, and spinal curvature. Analyses of differentially expressed genes (DEGs) indicated that changes in gene expression occurred in 340, 16, and 17 genes in the PS-NP, Mu, and PS-NP + Mu groups, respectively. Our results showed that PS-NP induced changes in mRNA expression and had toxic effects that caused phenotypic anomalies in the zebrafish embryos. However, further studies are necessary to investigate the effects of different types of plastic and properties on genotoxicity and phenotypic anomalies in aquatic organisms. A trend of reduction was found in genotoxicity and phenotypic anomalies when the embryos were exposed to PS-NP together with Mu, suggesting that Mu extracted from Aurelia aurita could reduce the genotoxicity of PS-NP.