Phospholipase A(2) subclasses in acute respiratory distress syndrome
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Kitsiouli, E.
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Πανεπιστήμιο Ιωαννίνων. Σχολή Θετικών Επιστημών. Τμήμα Χημείας
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Kitsiouli, E.
(EN)
phospholipases A(2), (PLA(2)) catalyse the cleavage of fatty acids esterified at the sn-2 position of glycerophospholipids. In acute lung injury-acute respiratory distress syndrome (ALI-ARDS) several distinct isoenzymes appear in lung cells and fluid Some are capable to trigger molecular events leading to enhanced inflammation and lung damage and others have a role in lung surfactant recycling preserving lung function Secreted forms (groups sPLA(2)-IIA, -V, -X) can directly hydrolyze surfactant phospholipids Cytosolic PLA(2) (cPLA(2)-IVA) requiring Ca(2+) has a preference for arachidonate, the precursor of etcosanoids which participate in the inflammatory response in the lung. Ca(2+) independent intracellular PLA(2)s (iPLA(2)) take part in surfactant phospholipids turnover within alveolar cells Acidic Ca(2+) -independent PLA(2) (aiPLA(2)). of lysosomal origin. has additionally antioxidant properties, (peroxiredoxin VI activity). and participates in the formation of dipalmitoyl-phosphatidylcholine in lung surfactant. PAF-AH degrades PAF. a potent mediator of inflammation, and oxidatively fragmented phospholipids but also leads to toxic metabolites. Therefore, the regulation of PLA(2) isoforms could be a valuable approach for ARDS treatment. (C) 2009 Elsevier B.V All rights reserved.
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