Chapter One - The Mechanistic Complexities of Phycotoxins: Toxicology of Azaspiracids and Yessotoxins

Azaspiracids and yessotoxins (YTX) are marine toxins that still pose a scientific problem with regard to their mechanism of action. Azaspiracids are toxins that were linked to anionic channels, hERK potassium channels, c-Jun-N-terminal protein kinase kinases, adhesion proteins, and calcium pools. Their mechanism of action, although unknown, causes apoptosis. YTX are less well understood, the primary unclear aspect being whether or not they are in fact toxins, since there are no reports of a human intoxication. Possible targets of YTX have been proposed to be adhesion proteins, phosphodiesterases, PKC, the AKAP complex, or calcium pools. It is unclear if this toxin causes apoptosis, autophagia, or both, depending on the cell type. Also, the mechanism of action has been proposed as a basis for several possible therapeutic uses, as anticancer or anti-Alzheimer’s drug.