Environmental monitoring by gene expression biomarkers in Barbus graellsii: Laboratory and field studies

Evaluation of environmental impact on natural populations of the Mediterranean killifish Aphanius fasciatus by quantitative RNA biomarkers

“…ß-naphthoflavone appeared as a weak, but steady inducer of CYP1A. The transient effect of Cd (and other heavy metals) in liver MT transcript abundance has been observed in different systems (Gonzalez et al, 2005;Quirós et al, 2007b). In natural fish populations, metal chronic exposure usually results in elevated MT mRNA levels in kidney and other tissues, but not necessarily in the liver (Hayes et al, 2004;Navarro et al, 2009;Quirós et al, 2007b;Tom et al, 1999).…”

“…This gene, and the enzymatic activity associated to its protein product, EROD, are classic markers of exposure to dioxin-like pollutants, like dioxins, other organochlorine compounds and polycyclic aromatic hydrocarbons (van der Oost et al, 2003;Whyte et al, 2000). Hepatic CYP1A mRNA abundance has been directly correlated to the presence of organic pollutants in different fish species (Jarque et al, 2010;Quirós et al, 2007b;Roberts et al, 2005;Roling et al, 2004). In contrast, metals tend to suppress, rather than induce, CYP1A expression (Bruschweiler et al, 1996).…”

“…In this context, markers based on RNA quantification methods, such qRT-PCR, provide a suitable alternative, as they only require minute amounts of sample Rotchell and Ostrander, 2003;Valasek and Repa, 2005). These techniques have proved their usefulness for monitoring of different types of environmental pollutants, like estrogens (Barucca et al, 2006;Garcia-Reyero et al, 2004;George et al, 2004), metals (Cheung et al, 2004;Navarro et al, 2009;Tom et al, 2004), and organic substances (Eljarrat et al, 2008;Quirós et al, 2007a;Quirós et al, 2007b). It is clear that biomarkers based on mRNA levels only reflect the initial steps of a cascade of events linking environmental insults to ecological impact (van der Oost et al, 2003).…”

“…In this work, we develop mRNA markers for monitoring A. fasciatus exposure to different kinds of pollutants, using known DNA sequences from evolutionarily related species (mainly Cyprinodonts and Percomorphs). Genes used in this analysis included the main metal-responsive metallothionein (MT) gene (Cheung et al, 2004;Navarro et al, 2009;Schlenk et al, 1995;Tom et al, 2004;Van Cleef-Toedt et al, 2001), the egg-forming, liver-expressed vitellogenin (Vtg), a known marker for estrogens (Barucca et al, 2006;Denslow et al, 2001;Garcia-Reyero et al, 2004), the dioxin-like responsive Cytochrome P4501A (CYP1A, Chung-Davidson et al, 2004;Craft et al, 2001;Quirós et al, 2007a;Quirós et al, 2007b), the oxidative stress-related gene Superoxide dismutase (SOD, Cho et al, 2006;Gonzalez et al, 2006;Pandey et al, 2003), and the protein chaperone HSP70, which are involved in the processing of missfolded proteins due to different kinds of stress (Carnevali and Maradonna, 2003;Maradonna and Carnevali, 2007;Schroder et al, 2000;Varo et al, 2002). In addition, probes for two housekeeping genes (ß actin and the elongation translation factor EF1)…”

Multi-biomarker responses as indication of contaminant effects in Gambusia affinis from impacted rivers by municipal effluents

“…Cytochrome P4501A (CYP1A) plays an important role in catalyzing oxidative metabolism of organic pollutants and has been used as a specific biomarker for exposure to aryl hydrocarbon receptor (AhR) agonists in fish such as PAHs and polychlorobiphenyls (PCBs) (Olivares et al, 2010;Maes et al, 2013). Both ethoxyresorufin O-deethylase activity (EROD) and CYP1A mRNA expression have been successfully used as common biomarkers for exposure to PAHs and PCBs in fish (Corsi et al, 2003;Quiró et al, 2007). Additionally, the inhibition of AChE activity is a specific biomarker for exposure to carbamate and organophosphorus pesticides (Corsi et al, 2003).…”