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bioRxiv · 10.1101/2021.01.11.425914

An insight into neurotoxic and toxicity of spike fragments SARS-CoV-2 by exposure environment: A threat to aquatic health?

Charlie-Silva, I.·Araujo, A.·Guimaraes, A.·Veras, F.·Braz, H.·Pontes, L.·Jorge, R.·Belo, M.·Fernandes, B.·Nobrega, R. H.·Galdino, G.·Condino-Neto, A.·Galindo-Villegas, J.·Machodo-Santelli, G.·Sanches, P.·Rezende, R.·Cilli, E.·Malafaia, G.
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Abstract

The Spike protein (S protein) is a critical component in the infection of the new coronavirus (SARS-CoV-2). The objective of this work was to evaluate whether peptides from S protein could cause negative impact in the aquatic animals. The aquatic toxicity of SARS-CoV-2 spike protein peptides derivatives has been evaluated in tadpoles (n = 50 tadpoles / 5 replicates of 10 animals) from species Physalaemus cuvieri (Leptodactylidae). After synthesis, purification, and characterization of peptides (PSDP2001, PSDP2002, PSDP2003) an aquatic contamination has been simulatedwith these peptides during 24 hours of exposure in two concentrations (100 and 500 ng/mL). The control group ("C") was composed of tadpoles kept in polyethylene containers containing de-chlorinated water. Oxidative stress, antioxidant biomarkers and neurotoxicity activity were assessed. In both concentrations, PSPD2002 and PSPD2003 increased catalase and superoxide dismutase antioxidants enzymes activities, as well as oxidative stress (nitrite levels, hydrogen peroxide and reactive oxygen species). All three peptides also increased acetylcholinesterase activity in the highest concentration. These peptides showed molecular interactions in silico with acetylcholinesterase and antioxidant enzymes. Aquatic particle contamination of SARS-CoV-2 has neurotoxics effects in P. cuvieri tadpoles. These findings indicate that the COVID-19 can constitute environmental impact or biological damage potential. HIGHLIGHTSO_LISARS-CoV-2 spike protein peptides (PSDP) were synthesized, purified, and characterized by solid phase peptide synthesis. C_LIO_LIPSDP peptides promoted REDOX imbalance and acute neurotoxicity in tadpoles (Physalaemus cuvieri) C_LIO_LIIn silico studies have shown interactionsbetween peptides and acetylcholinesterase and antioxidant enzymes C_LIO_LIAquatic particle contamination of SARS-CoV-2 can constitute additional environmental damage C_LI GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=106 SRC="FIGDIR/small/425914v1_ufig1.gif" ALT="Figure 1"> View larger version (49K): org.highwire.dtl.DTLVardef@1b86f96org.highwire.dtl.DTLVardef@1a6225corg.highwire.dtl.DTLVardef@19d953org.highwire.dtl.DTLVardef@10af7ff_HPS_FORMAT_FIGEXP M_FIG C_FIG

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Charlie-Silva, I., Araujo, A., Guimaraes, A., Veras, F., Braz, H., Pontes, L., Jorge, R., Belo, M., Fernandes, B., Nobrega, R. H., Galdino, G., Condino-Neto, A., Galindo-Villegas, J., Machodo-Santelli, G., Sanches, P., Rezende, R., Cilli, E., Malafaia, G.. 2021-01-13. An insight into neurotoxic and toxicity of spike fragments SARS-CoV-2 by exposure environment: A threat to aquatic health?. https://doi.org/10.1101/2021.01.11.425914

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