title: Influence of cadmium on the morphology and functionality of haemocytes in the compound ascidian Botryllus schlosseri.
abstract: In order to get insights into the effects of cadmium (Cd) on cell morphology and functions, we exposed haemocytes of the colonial ascidian Botryllus schlosseri to sub-lethal concentrations of CdCl(2). Results indicate that Cd hampers haemocyte spreading and phagocytosis in a dose-dependent way, through the alteration of the actin cytoskeleton. In addition, the metal decreases the stability of the internal membranes, as revealed by the Neutral Red assay. The fraction of cells showing positivity for the lysosomal enzyme acid phosphatase is also reduced in the presence of Cd, whereas the number of cells responsive to the Annexin-V assay and showing chromatin condensation increases, suggesting a metal-dependent induction of apoptosis in exposed cells. As Cd is a known cause of oxidative stress, the decrease in the percentage of cells positive to the assay for superoxide anion, observed at low Cd concentrations, is indicative of the synthesis of metal-chelating molecules, such as metallothioneins, whereas, the increase at high Cd concentrations suggests a depletion of the cell reducing redox potential.
authors.affiliation: Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Palermo, Italy.
authors.forename: Nicola
authors.initials: N
authors.lastname: Franchi
authors.forename: Loriano
authors.initials: L
authors.lastname: Ballarin
mesh_terms: D008841:Actin Cytoskeleton / Q000187:drug effects / Q000378:metabolism; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D002104:Cadmium / Q000633:toxicity*; D002448:Cell Adhesion / Q000187:drug effects; D016923:Cell Death / Q000187:drug effects; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D002470:Cell Survival / Q000187:drug effects; D002843:Chromatin / Q000187:drug effects / Q000378:metabolism; D006434:Hemocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D008247:Lysosomes / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D008668:Metallothionein / Q000378:metabolism; D010084:Oxidation-Reduction / Q000187:drug effects; D018384:Oxidative Stress / Q000187:drug effects; D010587:Phagocytosis / Q000187:drug effects; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism; D013481:Superoxides / Q000378:metabolism; D014561:Urochordata / Q000187:drug effects* / Q000378:metabolism
chemical_list: D002843:Chromatin; D002104:Cadmium; D013481:Superoxides; D008668:Metallothionein; D010744:Phosphoric Monoester Hydrolases