Mechanisms of Cyanotoxin Toxicity—Carcinogenicity, Anticancer Potential, and Clinical Toxicology

Abstract

Cyanoprokaryotes are distributed worldwide and they produce various bioactive compounds, including cyanotoxins. The major route of human exposure to cyanotoxins is the oral intake by using contaminated drinking water, by incidental intake of contaminated water during recreational and professional activities, and by consuming contaminated food or dietary supplements prepared from cyanobacteria. The prolonged chronic exposure to low concentrations of cyanotoxins provokes cell damage and may increase the risk for cancer development. Due to the variety of cyanotoxin chemical structures, different mechanisms of their toxic effects are known. At the same time, some of the natural compounds produced by cyanoprokaryotes have anticancer potential and are promising sources for the development of novel drugs. This chapter is dedicated to the target mechanisms behind the effects of the widely distributed cyanotoxins with an impact on human health, microcystins, nodularins, and cylindrospermopsin.

Contribution of Cyanotoxins to the Ecotoxicological Role of Lichens

“…A significant part of species within the Nostocales produce structurally diverse biologically active strain-specific secondary metabolites, mainly polyketides and non-ribosomal peptides. A number of them also exert different types and levels of toxicity and the cyclic pentapeptide nodularins and cyclic heptapeptide microcystins are the most widespread cyanotoxins in freshwater and brackish toxic blooms in various climatic regimes worldwide [47,48]. Often an individual strain is characterized by the ability to produce several classes of metabolically active compounds [49].…”