Research and collaboration

In vertebrates, fish early life stages are among the most sensitive to developmental toxicity caused by polycyclic aromatic hydrocarbons (PAHs), which includes detoxification enzymes induction (CYP1A), hemorrhaging, cardiovascular defects, pericardial and yolk sac edemas, craniofacial deformities, growth attenuation, etc. The cardiovascular tissue is the most sensitive to PAHs, and all the aforementioned symptoms are caused by the activation of the aryl hydrocarbon receptor (AhR). However, the mechanisms involved downstream of the AhR activation by PAHs are still unclear. Moreover, some weak AhR agonists such as phenanthrene can also produce cardiovascular defects via unknown AhR-independent mechanisms. Complex mixtures of PAHs can also alter the toxicity normally observed with single compounds: fluoranthene, for example, is a CYP1A inhibitor which can amplify the toxicity of AhR-agonistic PAHs such as retene or pyrene.

Our research is focused on understanding the mechanisms of toxicity by which different PAHs and their binary mixtures can cause cardiovascular toxicity in developing fish. We are using the rainbow trout (Oncorhynchus mykiss) as our model species. One of the tool we are using to try to achieve this goal are OMICs, i.e. the combined use of transcriptomics, proteomics and metabolomics. The use of OMICS can lead to strong evidence of which pathways are altered by PAHs, and thus help us choosing candidate proteins involved in their mechanisms of toxicity. We have several active collaborations in Finland and in Norway to help us achieve the different aspects of the OMICs tools we are using.

Another aspect of our research is focused on the effects of different PAHs and their binary mixtures on various morphometric parameters of the early life stages of the rainbow trout, such as growth, yolk sac consumption and blue sac disease (BSD) symptoms. Another huge focus of our research is put on studying the mechanical behavior of the heart (heart rate and its regularity) following exposure to those PAHs.

Some of our recent results can be found on those two posters which were presented during the last European SETAC meeting in May 2018, in Rome:

Assessment of the developmental cardiotoxicity of individual PAHs using integrated OMICS.

Induction of developmental cardiotoxicity in rainbow trout (Oncorhynchus mykiss) following PAH mixture exposure. New insights using an integrated OMICs approach.