The widespread use of bisphenol A (BPA) in polycarbonate plastics and epoxy resins has made it a prevalent environmental pollutant in aquatic ecosystems. BPA poses a significant threat to marine and freshwater wildlife due to its documented endocrine-disrupting effects on various species. Manufacturers are increasingly turning to other bisphenol compounds as supposedly safer alternatives.
View Article and Find Full Text PDFFish early life stages are well known for their sensitivity to crude oil exposure. However, the effect of crude oil exposure on adults and their gametes during their spawning period is not well studied. Polar cod, a key arctic fish, may be at risk for crude oil exposure during this potentially sensitive life stage.
View Article and Find Full Text PDFLipid metabolism is essential in maintaining energy homeostasis in multicellular organisms. In vertebrates, the peroxisome proliferator-activated receptors (PPARs, NR1C) regulate the expression of many genes involved in these processes. Atlantic cod () is an important fish species in the North Atlantic ecosystem and in human nutrition, with a highly fatty liver.
View Article and Find Full Text PDFSoil samples randomly taken from major e-waste sites in West Africa (Nigeria, Benin and Ghana) were examined for an extensive range of organic contaminants. Cytotoxicity measurements and assessment of activation of xeno-sensing receptors from fish (Atlantic cod) were employed as a battery of in vitro biological assays to explore the quality and toxicity profile of West African e-waste soil. The concentrations of the measured contaminants of emerging concerns (CECs) and persistent organic pollutants (POPs) in the e-waste soil differs significantly from the reference soil with chemical profiles typically dominated by legacy polybrominated diphenyl ethers (PBDEs) (405.
View Article and Find Full Text PDFArctic and sub-arctic pelagic organisms can be exposed to effluents and spills from offshore petroleum-related activities and thus it is important to understand how they respond to crude oil related contaminants such as polycyclic aromatic hydrocarbons (PAHs). The copepod species Calanus finmarchicus, Calanus glacialis and Calanus hyperboreus represent key links in the arctic marine food web. We performed a transcriptome analysis of the three species exposed to phenanthrene (Phe) and benzo[a]pyrene (BaP) representing low and high molecular weight PAHs, respectively.
View Article and Find Full Text PDFToxicity mediated by per- and polyfluoroalkyl substances (PFAS), and especially perfluoroalkyl acids (PFAAs), has been linked to activation of peroxisome proliferator-activated receptors (Ppar) in many vertebrates. Here, we present the primary structures, phylogeny, and tissue-specific distributions of the Atlantic cod (Gadus morhua) gmPpara1, gmPpara2, gmPparb, and gmPparg, and demonstrate that the carboxylic acids PFHxA, PFOA, PFNA, as well as the sulfonic acid PFHxS, activate gmPpara1 in vitro, which was also supported by in silico analyses. Intriguingly, a binary mixture of PFOA and the non-activating PFOS produced a higher activation of gmPpara1 compared to PFOA alone, suggesting that PFOS has a potentiating effect on receptor activation.
View Article and Find Full Text PDFUnlabelled: The Antarctic ecosystem is progressively exposed to anthropogenic contaminants, such as polycyclic aromatic hydrocarbons (PAHs). So far, it is largely unknown if PAHs leave a mark in the physiology of high-Antarctic fish. We approached this issue via two avenues: first, we examined the functional response of the aryl hydrocarbon receptor (Ahr), which is a molecular initiating event of many toxic effects of PAHs in biota.
View Article and Find Full Text PDFThe aim of the present study was to investigate effects of per- and polyfluoroalkyl substances (PFAS), both single compounds and a mixture of these, using precision-cut liver slices (PCLS) from Atlantic cod (Gadus morhua). PCLS were exposed for 48 h to perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA) and perfluorononanoate (PFNA) (10, 50 and 100 μM), and three mixtures of these at equimolar concentrations (10, 50 and 100 μM). Transcriptomic responses were assessed using RNA sequencing.
View Article and Find Full Text PDFPolycyclic aromatic hydrocarbons (PAHs) are among the most toxic and bioavailable components found in petroleum and represent a high risk to aquatic organisms. The aryl hydrocarbon receptor (Ahr) is a ligand-activated transcription factor that mediates the toxicity of 2,3,7,8-tetrachlorodibenzo--dioxin (TCDD) and other planar aromatic hydrocarbons, including certain PAHs. Ahr acts as a xenosensor and modulates the transcription of biotransformation genes in vertebrates, such as cytochrome P450 1A ().
View Article and Find Full Text PDFPhoto-enhanced toxicity of crude oil is produced by exposure to ultraviolet (UV) radiation. Atlantic cod (Gadus morhua) embryos were exposed to crude oil with and without UV radiation (290-400 nm) from 3 days post fertilization (dpf) until 6 dpf. Embryos from the co-exposure experiment were continually exposed to UV radiation until hatching at 11 dpf.
View Article and Find Full Text PDFVitamin D receptor (VDR) mediates the biological function of the steroid hormone calcitriol, which is the metabolically active version of vitamin D. Calcitriol is important for a wide array of physiological functions, including calcium and phosphate homeostasis. In contrast to mammals, which harbor one VDR encoding gene, teleosts possess two orthologous vdr genes encoding Vdr alpha (Vdra) and Vdr beta (Vdrb).
View Article and Find Full Text PDFA luciferase reporter gene-based bioassay battery consisting of stress-activated receptors from fish, complemented with traditional fish cell-based bioassays, were used to assess the toxicity of marine sediment samples from the Byfjorden area around the city of Bergen (Norway). The reporter assays covered a wide range of cellular signalling and metabolic pathways, representing different molecular initiating events in the adverse outcome pathway framework. Cytotoxicity, generation of reactive oxygen-species, and induction of 7-ethoxyresorufin-O-deethylase activity were analysed using fish liver and gill cell lines.
View Article and Find Full Text PDFPolar cod (Boreogadus saida) is a key species in the arctic marine ecosystem vulnerable to effects of pollution, particularly from petroleum related activities. To facilitate studying the effects of those pollutants, we adapted a precision-cut liver slice culture protocol for this species. Using this system on board a research vessel, we studied gene expression in liver slice after exposure to the polycyclic aromatic hydrocarbon (PAH) benzo[a]pyrene (BaP), ethynylestradiol (EE2), and their mixtures, to map their molecular targets and examine possible anti-estrogenic effects of BaP.
View Article and Find Full Text PDFHow an organism copes with chemicals is largely determined by the genes and proteins that collectively function to defend against, detoxify and eliminate chemical stressors. This integrative network includes receptors and transcription factors, biotransformation enzymes, transporters, antioxidants, and metal- and heat-responsive genes, and is collectively known as the chemical defensome. Teleost fish is the largest group of vertebrate species and can provide valuable insights into the evolution and functional diversity of defensome genes.
View Article and Find Full Text PDFThe aim of the present study was to investigate effects of defined mixtures of polycyclic aromatic hydrocarbons (PAHs) and perfluoroalkyl substances (PFASs), at low, environmentally relevant (1× = L), or high (20× = H) doses, on biological responses in Atlantic cod (Gadus morhua). To this end, farmed juvenile cod were exposed at day 0 and day 7 via intraperitoneal (i.p.
View Article and Find Full Text PDFThe aryl hydrocarbon receptor (Ahr) is a ligand-activated transcription factor that mediates the toxicity of dioxins and dioxin-like compounds (DLCs) in vertebrates. Two clades of the Ahr family exist in teleosts (Ahr1 and Ahr2), and it has been demonstrated that Ahr2 is the main protein involved in mediating the toxicity of dioxins and DLCs in most teleost species. Recently, we characterized the Atlantic cod (Gadus morhua) Ahr1a and Ahr2a receptors.
View Article and Find Full Text PDFThe aryl hydrocarbon receptor (Ahr) is a ligand-activated transcription factor that mediates the toxicity of halogenated and polycyclic aromatic hydrocarbons in vertebrates. Atlantic cod ( ) has recently emerged as a model organism in environmental toxicology studies, and increased knowledge of Ahr-mediated responses to xenobiotics is imperative. Genome mining and phylogenetic analyses revealed two Ahr-encoding genes in the Atlantic cod genome, and .
View Article and Find Full Text PDFScreening has revealed that modern-day feeds used in Atlantic salmon aquaculture might contain trace amounts of agricultural pesticides. To reach slaughter size, salmon are produced in open net pens in the sea. Uneaten feed pellets and undigested feces deposited beneath the net pens represent a source of contamination for marine organisms.
View Article and Find Full Text PDFThe dopaminergic effect of PAH and PFAS mixtures, prepared according to environmentally relevant concentrations, has been studied in juvenile female Atlantic cod ( Gadus morhua). Benzo[a]pyrene, dibenzothiophene, fluorene, naphthalene, phenanthrene, and pyrene were used to prepare a PAH mixture, while PFNA, PFOA, PFOS, and PFTrA were used to prepare a PFAS mixture. Cod were injected intraperitoneally twice, with either a low (1×) or high (20×) dose of each compound mixture or their combinations.
View Article and Find Full Text PDFThe aim of this study was to assess whether fish in Kollevåg, a sheltered bay on the western coast of Norway, previously utilized as a waste disposal site, could be affected by environmental contaminants leaking from the waste. Farmed, juvenile Atlantic cod (Gadus morhua) were caged for six weeks at three different locations in Kollevåg bay and at one reference location. Sediments and cod samples (bile and liver) were analyzed for polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), brominated flame retardants (BFRs), per-and polyfluoroalkyl substances (PFASs) and polycyclic aromatic hydrocarbon (PAH) metabolites, revealing a contamination gradient at the four stations.
View Article and Find Full Text PDFThe serum IgM concentration of ballan wrasse is relatively high, estimated to approximately 13 mg/ml in adult wild fish of 800 g. The present study revealed an unusual high abundance of IgM mRNA in the gut of ballan wrasse. Initially, transcripts encoding IgM, IgT, IgD, TCRα, TCRδ and CD3ε were quantified by RT-qPCR in several tissues of wild caught fish (approx.
View Article and Find Full Text PDF