Characterization of distinct apoptotic changes induced by okadaic acid and yessotoxin in the BE(2)-M17 neuroblastoma cell line.
Apoptotic changes induced by okadaic acid and yessotoxin in BE(2)-M17 neuroblastoma cells have been evaluated and quantified by combining classical methods and fast and sensitive fluorimetric microplate assays. The phosphatase inhibitor okadaic acid induced rapid time- and dose-dependent apoptotic changes in this cell line, which were evident after 1h at concentrations equal or higher than 500 nM. Decreased mitochondrial membrane potential by okadaic acid (IC(50)=350 nM at 1h) was followed by cell detachment (IC(50)=400 nM at 1h), changes in total nucleic acids content (50% of controls after 1h with 1000 nM okadaic acid), caspase-3 activation (3- to 4-fold increase at 6h) and increased Annexin-V binding (1.5-fold at 6h). Yessotoxin induced similar changes in BE(2)-M17 cells, although significant differences were found in the time-course and degree of apoptotic events induced by this phycotoxin, indicating a lower potency for yessotoxin when compared with okadaic acid. This is the first report on apoptogenic activity of yessotoxin.
Leira
F
F
ANFACO-CECOPESCA, Campus Universitario de Vigo, 36310 Vigo, Spain. fleira@anfaco.cesga.es
Alvarez
C
C
Vieites
J M
JM
Vieytes
M R
MR
Botana
L M
LM
D017304:Annexin A5 / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3; D020169:Caspases / Q000096:biosynthesis; D002448:Cell Adhesion / Q000187:drug effects; D053938:DNA Fragmentation / Q000187:drug effects; D004273:DNA, Neoplasm / Q000032:analysis / Q000096:biosynthesis; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000633:toxicity*; D004988:Ethers, Cyclic / Q000633:toxicity*; D007425:Intracellular Membranes / Q000187:drug effects / Q000502:physiology; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D008928:Mitochondria / Q000187:drug effects / Q000502:physiology; D008978:Mollusk Venoms / Q000633:toxicity*; D009447:Neuroblastoma / Q000473:pathology; D019319:Okadaic Acid / Q000633:toxicity*; D035964:Oxocins; D012334:RNA, Neoplasm / Q000032:analysis / Q000096:biosynthesis; D014407:Tumor Cells, Cultured
D017304:Annexin A5; D004273:DNA, Neoplasm; D004791:Enzyme Inhibitors; D004988:Ethers, Cyclic; D008978:Mollusk Venoms; D035964:Oxocins; D012334:RNA, Neoplasm; D019319:Okadaic Acid; D053148:Caspase 3; D020169:Caspases; C066632:yessotoxin