Cadmium induces an apoptotic response in sea urchin embryos.
Cadmium is a heavy metal toxic for living organisms even at low concentrations. It does not have any biological role, and since it is a permanent metal ion, it is accumulated by many organisms. In the present paper we have studied the apoptotic effects of continuous exposure to subacute/sublethal cadmium concentrations on a model system: Paracentrotus lividus embryos. We demonstrated, by atomic absorption spectrometry, that the intracellular amount of metal increased during exposure time. We found, using terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay, that long treatments with cadmium triggered a severe DNA fragmentation. We demonstrated, by immunocytochemistry on whole-mount embryos, that treatment with cadmium causes activation of caspase-3 and cleavage of death substrates alpha-fodrin and lamin A. Incubating the embryos since fertilization with Z-DEVD FMK, a caspase-3 inhibitor, we found, by immunocytochemistry, that cleavage by caspase-3 and cleavage of death substrates were inactivated.
Agnello
Maria
M
Dipartimento di Biologia Cellulare e dello Sviluppo "A. Monroy" Università degli Studi di Palermo, Viale delle Scienze ed.16, 90128 Palermo, Italy.
Filosto
Simone
S
Scudiero
Rosaria
R
Rinaldi
Anna M
AM
Roccheri
Maria C
MC
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D002104:Cadmium / Q000633:toxicity*; D002352:Carrier Proteins / Q000378:metabolism; D053148:Caspase 3 / Q000378:metabolism; D053938:DNA Fragmentation / Q000187:drug effects; D004625:Embryo, Nonmammalian / Q000166:cytology* / Q000187:drug effects* / Q000201:enzymology; D020287:In Situ Nick-End Labeling; D034882:Lamins / Q000378:metabolism; D008840:Microfilament Proteins / Q000378:metabolism; D012617:Sea Urchins / Q000166:cytology / Q000187:drug effects* / Q000196:embryology*; D013049:Spectrin
D002104:Cadmium; D002352:Carrier Proteins; D053148:Caspase 3; D034882:Lamins; D008840:Microfilament Proteins; D013049:Spectrin