Differential Gene Expression Induced by Acute Exposure to Water Accommodated Fraction (WAF) and Chemically Enhanced WAF (CEWAF) of Light Crude Oil and Nokomis 3-F4 in Limulus polyphemus Larvae

Abstract

In 2018 we evaluated at 48 h and 96 h, the gene expression profile of larvae of Limulus polyphemus exposed to 10% and 100% of water-accommodated fraction (WAF) of light crude oil (API 35), and 10% and 100% of a chemically enhanced WAF (CEWAF) with the dispersant Nokomis 3-F4® in a static-acute (96 h) bioassay. Alkanes and PAHs concentrations were higher in CEWAF than in WAF stock solutions. Under the proved conditions, the expression profile of genes associated to detoxification processes (glutathione S-transferase and glutathione peroxidase), stress (heat shock protein), innate immunity (tumor necrosis factor receptor-associated factor 4 traf4), cell death (apoptosis inhibitor 5) and DNA repairing (E3 ubiquitin protein ligase), showed a deregulation at 48 h followed by an upregulation at 96 h, with exception of glutathione peroxidase, heat shock protein and innate immunity that remained low in CEWAF. In conclusion, by using genes that have been proposed as biomarkers to pollutants exposure, L. polyphemus larvae showed an early activation of genes related to the immune system, antioxidant, heat shock and NER.

Keywords: Acute toxicity; Gene expression; Light crude oil; Limulus polyphemus; Nokomis 3-F4.