title: Effect of dermaseptin on erythrocytes.
abstract: Dermaseptin, an antimicrobial peptide participating in the host defence against pathogens, interacts with the membrane of target cells, leading to membrane permeabilization and eventual cell lysis. Dermaseptin has previously been shown to trigger haemolysis. Prior to haemolysis, erythrocytes may enter suicidal death or eryptosis, which is characterized by cell shrinkage and by cell membrane scrambling leading to phosphatidylserine exposure at the erythrocyte surface. Triggers of eryptosis include increase in cytosolic Ca²⁺ activity [(Ca²⁺)](i) and formation of ceramide. This study explored whether dermaseptin modifies [Ca²⁺](i) and elicits eryptosis. Cell volume has been estimated from forward scatter, phosphatidylserine exposure from annexin-V binding, haemolysis from haemoglobin release, ceramide formation from binding of fluorescent antibodies and [Ca²⁺](i) from Fluo3-fluorescence. A 48-hr exposure to dermaseptin (50 μM) was followed by a significant increase in [Ca²⁺](i), a significant increase ceramide abundance, a significant decrease in forward scatter and a significant increase in annexin-V binding. The annexin-V binding after dermaseptin treatment was significantly blunted but not abrogated in the nominal absence of extracellular Ca²⁺. Dermaseptin triggers eryptosis, an effect at least partially due to entry of extracellular Ca²⁺.
authors.affiliation: Physiologisches Institut, der Universität Tübingen, Tübingen, Germany.
authors.forename: Majed
authors.initials: M
authors.lastname: Abed
authors.forename: Kousi A L
authors.initials: KA
authors.lastname: Zoubi
authors.forename: Michael
authors.initials: M
authors.lastname: Theurer
authors.forename: Florian
authors.initials: F
authors.lastname: Lang
mesh_terms: D029845:Amphibian Proteins / Q000494:pharmacology*; D017304:Annexin A5 / Q000378:metabolism; D023181:Antimicrobial Cationic Peptides / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D002118:Calcium / Q000378:metabolism*; D002462:Cell Membrane / Q000187:drug effects; D048429:Cell Size / Q000187:drug effects; D002518:Ceramides / Q000378:metabolism; D003600:Cytosol / Q000187:drug effects / Q000378:metabolism; D004912:Erythrocytes / Q000187:drug effects*; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D010718:Phosphatidylserines / Q000378:metabolism
chemical_list: D029845:Amphibian Proteins; D017304:Annexin A5; D023181:Antimicrobial Cationic Peptides; D002518:Ceramides; D010718:Phosphatidylserines; C070905:dermaseptin; D002118:Calcium