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PubMed · 10978743

Membrane permeabilization induced by discodermin A, a novel marine bioactive peptide.

K Sato·K Horibe·K Amano·M Mitusi-Saito·M Hori·S Matsunaga·N Fusetani·H Ozaki·H Karaki
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Abstract

The effects of discodermin A (DC-A), a novel marine bioactive peptide extracted from sea sponge Discodermia kiiensis, on the vascular smooth muscle cells and tissues were examined. Analysis with a confocal laser microscope showed that DC-A (0.1-30 microM) permeabilized the plasma membrane of A10 cells to the non-permeable fluorescent agents, ethidium homodimer-1 (MW = 857) and calcein (MW = 623), in a concentration-dependent manner. In the vascular tissue treated with 30 microM DC-A, addition of a micromolar concentration of Ca(2+) evoked a sustained contraction in the presence of ATP, suggesting that DC-A increased the permeability of the membrane to Ca(2+) and ATP. DC-A at higher concentrations (30 microM) significantly increased the leakage of lactate dehydrogenase (140 kD) from the vascular tissue. These results suggest that DC-A has a permeabilizing effect on the plasma membrane possibly by interacting with plasma membrane phospholipids with its six successive hydrophobic amino acid residues at N-terminal.

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Adenosine TriphosphateAmphibian ProteinsAnimalsAntimicrobial Cationic PeptidesCalciumCell Membrane PermeabilityCells, CulturedEthidiumFluoresceinsFluorescent DyesMuscle, Smooth, VascularRabbitsRatsJournal ArticleResearch Support, Non-U.S. Gov't

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K Sato, K Horibe, K Amano, M Mitusi-Saito, M Hori, S Matsunaga, N Fusetani, H Ozaki, H Karaki. Membrane permeabilization induced by discodermin A, a novel marine bioactive peptide.. https://doi.org/10.1016/s0041-0101(00)00123-9

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