Herein, the effect of dietary inclusion of insect (Tenebrio molitor) meal on hepatic pathways of apoptosis and autophagy in three farmed fish species, gilthead seabream (Sparus aurata), European seabass (Dicentrarchus labrax) and rainbow trout (Oncorhynchus mykiss), fed diets at 25%, 50% and 60% insect meal inclusion levels respectively, was investigated. Hepatic proteome was examined by liver protein profiles from the three fish species, obtained by two-dimensional gel electrophoresis. Although cellular stress was evident in the three teleost species following insect meal, inclusion by T. molitor, D. labrax and O. mykiss suppressed apoptosis through induction of hepatic autophagy, while in S. aurata both cellular procedures were activated. Protein abundance showed that a total of 30, 81 and 74 spots were altered significantly in seabream, European seabass and rainbow trout, respectively. Insect meal inclusion resulted in individual protein abundance changes, with less number of proteins altered in gilthead seabream compared to European seabass and rainbow trout. This is the first study demonstrating that insect meal in fish diets is causing changes in liver protein abundances. However, a species-specific response both in the above mentioned bioindicators, indicates the need to strategically manage fish meal replacement in fish diets per species.
Financial support for the trial on European sea bass was provided by the AQUAEXEL Project PROINSECTLIFE (Ref. No. 0013/03/05/15B), the AQUAEXEL Project INDIFISH (Ref. No. 0125/08/05/15/TNA), and by the University of Turin (ex 60%) Grant (Es. fn. 2014). NP (Scholarship Code: 1752) has been fnancially supported by the General Secretariat for Research and Technology (GSRT) of Greece and the Hellenic Foundation for Research and Innovation (HFRI) and MM by the Operational Programme “Human Resources Development, Education
and Lifelong Learning” in the context of the project “Strengthening Human Resources Research Potential via Doctorate Research” (MIS-5000432) as implemented by the State Scholarships Foundation (ΙΚΥ). Tanks to Evelyn Argo and Craig Pattinson (University of Aberdeen) for providing help with 2DE. EM was fnancially supported by Marine Alliance for Science and Technology Scotland (MASTS) visiting Fellowship.