Non-targeted metabolomics reveals alterations in liver and plasma of gilt-head bream exposed to oxybenzone

Abstract

The extensive use of the organic UV filter oxybenzone has led to its ubiquitous occurrence in the aquatic environment, causing an ecotoxicological risk to biota. Although some studies reported adverse effects, such as reproductive toxicity, further research needs to be done in order to assess its molecular effects and mechanism of action. Therefore, in the present work, we investigated metabolic perturbations in juvenile gilt-head bream (Sparus aurata) exposed over 14 days via the water to oxybenzone (50 mg/L). The non-targeted analysis of brain, liver and plasma extracts was performed by means of UHPLC-qOrbitrap MS in positive and negative modes with both C18 and HILIC separation. Although there was no mortality or alterations in general physiological parameters during the experiment, and the metabolic profile of brain was not affected, the results of this study showed that oxybenzone could perturb both liver and plasma metabolome. The pathway enrichment suggested that different pathways in lipid metabolism (fatty acid elongation, α-linolenic acid metabolism, biosynthesis of unsaturated fatty acids and fatty acid metabolism) were significantly altered, as well as metabolites involved in phenylalanine and tyrosine metabolism. Overall, these changes are signs of possible oxidative stress and energy metabolism modification. Therefore, this research indicates that oxybenzone has adverse effects beyond the commonly studied hormonal activity, and demonstrates the sensitivity of metabolomics to assess molecular-level effects of emerging contaminants.

FELLA: an R package to enrich metabolomics data

“…To demonstrate its usefulness outside human studies, FELLA is applied to two datasets from a gilt-head bream study [20] and a mouse model of non-alcoholic fatty liver disease [21]. The complete analyses can be respectively found in Additional files 3 and 4, whereas their respective R workspaces are saved in Additional files 6 and 7.…”

“…A study of the consequences of the oxybenzone contaminant on gilt-head bream [20] found five dysregulated KEGG metabolites in their liver and eleven in their plasma. The study justified its findings through literature and complemented them with insights provided by FELLA .…”

“…Among the suggested metabolites, “Tyrosine” is of particular help to explain the connection between the affected metabolites (see Fig. 2 from [20]).…”

“…Seven pathways are suggested, from which “Linoleic acid metabolism”, “Biosynthesis of unsaturated fatty acids”, “alpha-Linolenic acid metabolism”, “Glycerophospholipid metabolism” and “Glycine, serine and threonine metabolism” were used to build a comprehensive picture of the metabolic changes in the original manuscript (Fig. 3 from [20]). Such figure brings a structured overview that narrows down the core processes, also backed up by prior publications.…”

Shedding Light on the Bacterial Resistance to Toxic UV Filters: A Comparative Genomic Study

“…Their occurrence was reported in freshwater and marine environments from the surface microlayer 2 , water column 3,4 to sediments [5][6][7] , along with their bioaccumulation and biomagni cation properties 8 . UV lters toxicity was demonstrated on a broad range of organisms [9][10][11][12][13][14][15] , including bacteria 16 , yet UV lters toxicity mechanisms remain unclear. Bacteria are an interesting ecotoxicological model as they are easy to handle, constitute a major part of the marine biomass 17 , and support essential function in marine ecosystems 18 .…”