Ecotoxicidade de curto prazo de peptideos do SARS-CoV-2 e poluentes emergentes em larvas de Cloeon dipterum (EPHEMEROPTERA: BAETIDAE)

Abstract

The introduction of SARS-CoV-2 or its fragments into freshwater ecosystems, through domestic or hospital sewage, has raised concerns about its possible impacts on aquatic organisms. To investigate these effects, ephemeral larvae [Cloeon dipterum (L.), Ephemeroptera: Baetidae] were used as an experimental model, with the aim of evaluating the impacts of short exposure to peptides derived from SARS-CoV-2 (named PSPD-2001, PSPD 2002 and PSPD-2003, at a concentration of 266.2 ng/L) in combination with several emerging pollutants at environmental concentrations. After six days of exposure, an increase in the mortality of larvae exposed to SARS-CoV-2-derived peptides was observed, both alone and in combination with the pollutant mixture, and a reduction in body condition index compared to unexposed larvae. In the "PSPD" and "Mix + PSPD" groups, there was a decrease in the activity of the enzyme’s superoxide dismutase, catalase, in the DPPH radical scavenging activity and in the total thiol levels compared to the "control" group. In addition, it was identified the induction of nitrosative stress, indicated by increased nitrite production, and a reduction in acetylcholinesterase activity due to peptides derived from SARS-CoV-2. On the other hand, malondialdehyde levels in larvae exposed to the treatments were significantly lower than in unexposed larvae. The integrated biomarker response index values and the principal component analysis (PCA) results confirmed the similarity between the responses of animals exposed to SARS-CoV-2-derived peptides, both alone and in combination with the pollutant mixture. Although viral peptides did not exacerbate the effects of mixing pollutants, our study highlights the potential ecotoxicological risk associated with the presence of the novel coronavirus in aquatic environments. Therefore, it is important to explore this theme in other organisms and experimental contexts.