The Phycotoxin Domoic Acid as a Potential Factor for Oxidative Alterations Enhanced by Climate Change

Abstract

Harmful algal blooms (HAB) threaten aquatic and marine ecosystems and wildlife through the creation of hypoxic conditions, and through the toxins they produce. Climate change is creating conditions that increase the impact of HAB on the aquatic ecosystems, rising the frequency of these events. Domoic acid (DA) is a marine phycotoxin produced during HAB of the diatoms Pseudonitzchia sp. It was described that DA causes production of reactive oxygen species (ROS), neurological dysfunction, DNA damage, lipid peroxidation, energy depletion, mitochondrial damage and cell death in animals and humans. However, the information about the effect of this phycotoxin on the non-toxin producing phytoplankton community is scarce or null in relation to oxidative stress measurements. The hypothesis of this opinion article is that DA produced by HAB, might favor the generation of reactive species, that through diffusion to the extracellular environment modifies the oxidative metabolism of non-toxin-producing marine phytoplankton. This feature opens the possibility that not only the phytoplankton community, but also the rest of the food web might be deeply affected if, due to global warming, HAB magnitude and frequency continue increasing.