Cytotoxicity of diatom-derived oxylipins in organisms belonging to different phyla.
The cytotoxicity of several saturated and unsaturated marine diatom-derived aldehydes and an oxo-acid have been screened in vitro and in vivo against different organisms, such as bacteria, algae, fungi, echinoderms, molluscs and crustaceans. Conjugated unsaturated aldehydes like 2E,4E-decadienal, 2E,4E-octadienal, 5E,7E-9-oxo-nonadienoic acid and 2E-decenal were active against bacteria and fungi and showed weak algicidal activity. By contrast, the saturated aldehyde decanal and the non-conjugated aldehyde 4Z-decenal had either low or no significant biological activity. In assays with oyster haemocytes, 2E,4E-decadienal exhibited a dose-dependent inhibition of cytoskeleton organisation, rate of phagocytosis and oxidative burst and a dose-dependent promotion of apoptosis. A maternal diatom diet that was rich in unsaturated aldehydes induced arrest of cell division and apoptotic cell degradation in copepod embryos and larvae, respectively. This wide spectrum of physiological pathologies reflects the potent cell toxicity of diatom-derived oxylipins, in relation to their non-specific chemical reactivity towards nucleophilic biomolecules. The cytotoxic activity is conserved across six phyla, from bacteria to crustaceans. Deregulation of cell homeostasis is supposed to induce the elimination of damaged cells through apoptosis. However, efficient protection mechanisms possibly exist in unicellular organisms. Experiments with a genetically modified yeast species exhibiting elevated membrane and/or cell wall permeability suggest that this protection can be related to the inability of the oxylipin compounds to enter the cell.
Max-Planck Institute, Hans-Knöll-Str. 8, D-07745 Jena, Germany.
Sven
S
Adolph
Stéphane
S
Bach
Marc
M
Blondel
Anne
A
Cueff
Marjolaine
M
Moreau
Georg
G
Pohnert
Serge André
SA
Poulet
Thomas
T
Wichard
Alga
A
Zuccaro
D000447:Aldehydes / Q000633:toxicity*; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D001419:Bacteria / Q000187:drug effects*; D001681:Biological Assay; D003599:Cytoskeleton / Q000187:drug effects; D017377:Diatoms / Q000737:chemistry*; D004121:Dimethyl Sulfoxide; D004305:Dose-Response Relationship, Drug; D056890:Eukaryota / Q000187:drug effects*; D005658:Fungi / Q000187:drug effects*; D007448:Invertebrates / Q000187:drug effects*; D008387:Marine Toxins / Q000633:toxicity*; D008856:Microscopy, Fluorescence; D010587:Phagocytosis / Q000187:drug effects; D016897:Respiratory Burst / Q000187:drug effects
D000447:Aldehydes; D008387:Marine Toxins; D004121:Dimethyl Sulfoxide