Aquaculture is crucial to keep pace with the increasing fish demand, however, the industry faces its own sustainability challenges to attain such endeavor. Managing fish stress is crucial to avoid negative impacts on fish health/welfare, and ultimately, on the aquaculture productivity. In this study, an integrated proteomics and metabolomics characterization of the fish liver, a central organ during stress adaptation, was performed to provide a holistic assessment of the molecular stress response at different organizational levels. Widen our understanding into the physiological changes occurring in the fish organism during stress exposure/adaptation can leverage the industry with the scientific knowledge for forthcoming species-specific welfare assessment protocols.
Sparus aurata was exposed to a net handling challenge, along with fish reared under optimal conditions, as control. Nets were designed for the purpose, fitted inside the tanks and the fish were lifted and air-exposed for 1 min four times a week, during 1 &fraq12; months. Extracts from liver samples were prepared for further proteomics and metabolomics analysis by LC-MS/MS. Pairwise comparisons among identified proteins and metabolites, were achieved by a student’s t-test, p < 0.05; FDR controlled at 0.05. Integrative analysis of both data modalities was achieved by the Data Integration Analysis for Biomarker discovery using Latent components (DIABLO) algorithm.
A total of 326 proteins and 40 metabolites were differentially regulated between challenged and control fish, mostly implicated in cellular processes and metabolism related KEGG pathways, namely amino acid and carbohydrate metabolism, inflammatory response, protein folding processes, among others. A STITCH protein-metabolism interaction network revealed a coordinated response of the hepatic system to the challenge. Enrichment analysis of the variables selected by the DIABLO algorithm (Fig.1) revealed up-regulation of different pro-survival pathways such as the unfolded protein response (UPR), endocytosis, mTORC1 pathway, among others. These results shed light on the dynamics and extent of this species’ metabolic reprogramming under chronic stress, supporting future studies on stress markers’ discovery and fish welfare research.