Specific metabolic signatures of fish exposed to cyanobacterial blooms

Abstract With the increasing impact of the global warming, occurrences of cyanobacterial blooms in aquatic ecosystems are becoming a main ecological concern around the world. Due to their capacity to produce potential toxic metabolites, interactions between the cyanobacteria/cyanotoxin complex and the other freshwater organisms have been widely studied in the past years. Non-targeted metabolomic analyses have the powerful capacity to study a high number of metabolites at the same time and thus to understand in depth the molecular interactions between various organisms in different environmental scenario and notably during cyanobacterial blooms. In this way during summer 2015, liver metabolomes of two fish species, sampled in peri-urban lakes of the île-de-France region containing or not high concentrations of cyanobacteria, were studied. The results suggest that similar metabolome changes occur in both fish species exposed to cyanobacterial blooms compared to them not exposed. Metabolites implicated in protein synthesis, protection against ROS, steroid metabolism, cell signaling, energy storage and membrane integrity/stability have shown the most contrasted changes. Furthermore, it seems that metabolomic studies will provide new information and research perspectives in various ecological fields and notably concerning cyanobacteria/fish interactions but also a promising tool for environmental monitoring of water pollutions.