Nanopollutants (nZnO) exacerbate hypoxia-induced cellular damage and impair cellular adaptation mechanisms in Mytilus edulis

This is a dataset of cellular and molecular stress-related biomarkers in the gills and the digestive gland of the Baltic Sea blue mussels Mytilus edulis exposed to short-term and long-term hypoxia and subsequent reoxygenation in the presence or absence of nZnO. The grey shaded cells show missing values or statistical outliers not used in further statistical analyses. 

Abstract. The rising application of zinc oxide nanoparticles (nZnO) in industrial and medical fields raises concerns regarding their impact on coastal ecosystems. The Baltic Sea, characterized by severe eutrophication, simultaneously confronts hypoxia and nZnO contamination, yet the interactions between these stressors remain insufficiently studied. This study investigates the combined effects of nZnO exposure and fluctuating dissolved oxygen regimes (specifically short- and long-term hypoxia and subsequent reoxygenation) on Mytilus edulis, a sentinel species in these ecosystems. By assessing a range of cellular and molecular markers, including oxidative stress, oxygen sensing, protein quality control, stress response, apoptosis, and inflammation, we reveal that nZnO exacerbates hypoxia-induced oxidative damage and significantly impairs recovery during reoxygenation. While M. edulis is resilient to short-term hypoxia and rapidly recovers even from a prolonged hypoxia-induced stress, nZnO exposure delays the restoration of redox balance, disrupts cellular stress responses, and alters the regulation of key protein-folding and apoptotic pathways. These findings demonstrate a synergistic interaction between nZnO and hypoxia, heightening the organism's vulnerability to environmental stress and suggesting risks for marine organisms in nanoparticle-polluted, hypoxia-prone coastal regions.