In vitro approaches to evaluate palytoxin-induced toxicity and cell death in intestinal cells.
Palytoxin isolated from the genus Palythoa is the most potent marine toxin known. The aim of the present study was to quantify palytoxin-induced cellular injury in the human intestinal cell line Caco-2. Cellular damage was measured by evaluating cell proliferation, cell membrane permeability, cell morphology and apoptotic markers. Furthermore, changes in F-actin were studied after exposure of cells to increasing amounts of palytoxin. The results show that cell proliferation decreased in a concentration-dependent manner with a mean IC(50) value of about 0.1 nM. A noticeable increase of cell detachment correlated with cell rounding and F-actin depolymerization was observed in palytoxin-treated cells. Moreover LDH was released from the cells in a dose and time dependent manner, although under these conditions there was no propidium iodide uptake. On the other hand, palytoxin impaired mitochondrial activity but other apoptotic markers, such as DNA fragmentation or caspases activation, were not observed. The results obtained in this paper suggest that the effects of palytoxin in Caco-2 cells were very potent and unspecific, since a primary necrosis and a secondary apoptosis seem to occur under these conditions.
Valverde
I
I
ANFACO-CECOPESCA, Campus Univ de Vigo, Vigo 36310, Spain.
Lago
J
J
Vieites
J M
JM
Cabado
A G
AG
D000178:Acrylamides / Q000378:metabolism / Q000633:toxicity*; D000199:Actins / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects; D018938:Caco-2 Cells; D020169:Caspases / Q000378:metabolism; D002448:Cell Adhesion / Q000187:drug effects; D002463:Cell Membrane Permeability / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D003064:Cnidarian Venoms; D053938:DNA Fragmentation; D004305:Dose-Response Relationship, Drug; D020895:Enterocytes / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D006801:Humans; D007413:Intestinal Mucosa / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008564:Membrane Potentials / Q000187:drug effects; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D009336:Necrosis / Q000139:chemically induced; D000095702:Polyether Toxins
D000178:Acrylamides; D000199:Actins; D020169:Caspases; D003064:Cnidarian Venoms; D007770:L-Lactate Dehydrogenase; C010272:palytoxin; D000095702:Polyether Toxins