Metabolites of the phospholipase D pathway regulate H2O2-induced filamin redistribution in endothelial cells

✍ Scribed by Laurie E. Hastie; Wayne F. Patton; Herbert B. Hechtman; David Shepro

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 268 KB
• Volume: 68
• Category: Article
• ISSN: 0730-2312
• DOI: 10.1002/(sici)1097-4644(19980315)68:4<511::aid-jcb10>3.0.co;2-c

✦ Synopsis

Hypoxia/reoxygenation injury to cultured endothelial cells results in cytoskeletal rearrangement and second messenger activation related to increased monolayer junctional permeability. Cytoskeletal rearrangement by reactive oxygen species may be related to specific activation of the phospholipase D (PLD) pathway. Human umbilical vein endothelial cell monolayers are exposed to H 2 O 2 (100 µM) or metabolites of the PLD pathway for 1-60 min. Changes in cAMP levels, Ca 2ϩ levels, PIP 2 production, filamin distribution, and intercellular gap formation are then quantitated. H 2 O 2 -induced filamin translocation from the membrane to the cytosol occurs after 1-min H 2 O 2 treatment, while intercellular gap formation significantly increases after 15 min. H 2 O 2 and phosphatidic acid exposure rapidly decrease intracellular cAMP levels, while increasing PIP 2 levels in a Ca 2ϩ -independent manner. H 2 O 2 -induced cAMP decreases are prevented by inhibiting phospholipase D. H 2 O 2 -induced cytoskeletal changes are prevented by inhibiting phospholipase D, phosphatidylinositol-4-phosphate kinase, phosphoinositide turnover, or by adding a synthetic peptide that binds PIP 2 . These data indicate that metabolites produced downstream of H 2 O 2 -induced PLD activation may mediate filamin redistribution and F-actin rearrangement.