Public Dissemination Event

El Puerto de Santa María, 3rd October 2019

Microalgal extracts as epigenetic regulators of fish plasticity

Abstract:

 

Carlos Carballo (1,2); Ana Patricia Mateus (3,4); Lalia Mantecón (5); Deborah M. Power (3); and Manuel Manchado (1,6)

 

1 IFAPA Centro El Toruño, Junta de Andalucía, Camino Tiro Pichón s/n, 11500 El Puerto de Santa María, Cádiz, Spain

2 Universidad de Málaga, Departamento de Microbiologia, Campus de Teatinos, 29071, Málaga, Spain

3 Centre of Marine Sciences (CCMAR), Universidade do Algarve, Campus de Gambelas, 8005-139, Faro, Portugal

4 Escola Superior de Saúde da Universidade do Algarve, Campus de Gambelas, 8005-139, Faro, Portugal

5 Fitoplanton Marino S.L., 11500, El Puerto de Santa María, Spain

6 “Crecimiento Azul", Centro IFAPA El Toruño, Unidad Asociada al CSIC”

 

ABSTRACT

Epigenetic reprograming of larvae plasticity is an innovative way to modulate fish performance that can be exploited in aquaculture. Although microalgae are mainly used as a larval feed in this industry, they contain a plethora of bioactive compounds that might be useful to modulate fish plasticity. However, this potential use remains still unexplored. In this study we evaluate the potential capacity of marine microalgae extracts to modify plasticity of early larval stages in fish. Hatched larvae of the flatfish sole were immersed in whole-cell extracts of four microalgae for two hours. Expression profiles at 4 h determined a significant down-regulation of DNA methyltransferases in embryos treated with Nannochloropsis gaditana extract (Nano) indicating a shift in larval reprogramming. To evaluate the possible effects on fish performance, three tests were carried out: a) Monitoring of growth in fish larvae and in juveniles using a longitudinal approach. In both cases, Nano-treated larvae grew faster than the controls; b) Thermal tolerance test in post-larvae and juveniles. Nano-treated and T-iso-treated fish showed a higher survival after a heat shock. This effect was not evident after a cold-shock; c) Immune system training in post-larvae. Steady-state levels of immune related genes of Nanno-treated and controls responded differently when supplied with a microalgal extract enriched product or yeast beta-glucans or after a challenge with LCDV. Nanno-treated larvae were highly susceptible to anoxia and underwent metabolic reprogramming and this enhanced the expression of the antiviral genes and pro-inflammatory cytokines and the transcript levels interact with yeast beta glucans. All these data indicate a novel use of microalgal extracts to benefit fish larval plasticity.

 

Acknowledgements

This research has been funded by the project Algae4A&B from the UE H2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 691102 and the project SoleAlgae FEDER Andalucía PP.AVA.AVA201601.9. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript