Regular Article
Oxidants Depress the Synthesis of Phosphatidylinositol 4,5-Bisphosphate in Heart Sarcolemma

https://doi.org/10.1006/abbi.2000.2012Get rights and content

Abstract

Phosphatidylinositol 4,5-bisphosphate (PtdIns 4,5-P2) is the substrate for phosphoinositide–phospholipase C (PLC) and is required for the function of several cardiac cell plasma membrane (sarcolemma, SL) proteins. PtdIns 4,5-P2 is synthesized in the SL membrane by coordinated and successive actions of PtdIns 4-kinase and PtdIns 4-phosphate 5-kinase. These kinases and the generation of PtdIns 4,5-P2 may be a factor in the cardiac dysfunction during pathophysiological conditions of oxidative stress. Therefore, we examined the effects of different reactive oxygen species (ROS) on the kinases' activities and subsequent generation of PtdIns 4,5-P2. Exposure to the xanthine–xanthine oxidase–ROS generating system significantly reduced both SL kinase activities. Superoxide dismutase did not prevent this inhibition; however, catalase significantly prevented the xanthine–xanthine oxidase induced inhibition. Treatment of SL with hydrogen peroxide (H2O2) resulted in inhibition of both the kinases, which was prevented by catalase and dithiothreitol (DTT). Hypochlorous acid also inhibited both the kinases, which was prevented by DTT. Deferoxamine (an iron chelator) and mannitol (an •OH scavenger) did not modify the H2O2-induced depression of the kinases, eliminating any role of •OH. Furthermore, the IC50 of H2O2 on PtdIns 4-kinase and PtdIns 4-P 5-kinase was 27 and 81 μM, respectively. In addition, inclusion of reduced glutathione in the assay of the kinases in the absence of H2O2 did not affect the activities of the kinases; however, oxidized glutathione induced a significant depression. Also, a significant decline of the PtdIns 4-kinase and PtdIns 4-P 5-kinase activities due to changing of the redox ratio was observed. Thiol modifiers (N-ethylmaleimide, methyl methanethiosulfonate, or p-chloromercuriphenylsulfonic acid) were detected to depress the kinases' activities, which were substantially prevented by DTT. The results suggest that functionally critical thiol groups may be associated with PtdIns 4-kinase and PtdIns 4-P 5-kinase and that changes of their redox state by ROS can impair their activities, which may be an important factor in the oxidant-induced cardiac dysfunction.

References (52)

  • K.F. Tolias et al.

    Chem. Phys. Lipids

    (1999)
  • S.B. Lee et al.

    Curr. Opin. Cell Biol.

    (1995)
  • A. Toker

    Curr. Opin. Cell Biol.

    (1998)
  • H.W. De Jonge et al.

    J. Mol. Cell. Cardiol.

    (1995)
  • H. Kamata et al.

    Cell. Signal.

    (1999)
  • J.-I. Abe et al.

    Trends Cardiovasc. Med.

    (1998)
  • Y.J. Suzuki et al.

    J. Mol. Cell. Cardiol.

    (1999)
  • V. Panagia et al.

    Biochim. Biophys. Acta

    (1991)
  • M. Kaneko et al.

    Biochim. Biophys. Acta

    (1990)
  • J.T.A. Meij et al.

    Biochim. Biophys. Acta

    (1994)
  • S.-Y. Liu et al.

    Biochim. Biophys. Acta

    (1997)
  • P.R. van Iwaarden et al.

    Biochim. Biophys. Acta

    (1992)
  • X. Shan et al.

    Pharmacol. Ther.

    (1990)
  • B.E. Britigan et al.

    J. Biol. Chem.

    (1990)
  • L.E.S. Netto et al.

    J. Biol. Chem.

    (1996)
  • R.A. Josephson et al.

    J. Biol. Chem.

    (1991)
  • A. Beresewicz et al.

    J. Mol. Cell. Cardiol.

    (1991)
  • C.A. Ward et al.

    J. Mol. Cell. Cardiol.

    (1995)
  • M.A. Frohman et al.

    Chem. Phys. Lipids

    (1999)
  • N. Mesaeli et al.

    Mol. Cell. Biochem.

    (1992)
  • J.C. Gilbert et al.

    Circ. Res.

    (1991)
  • O.G. Loewe et al.

    Am. J. Physiol.

    (1988)
  • P.K. Singal et al.

    Cardiovasc. Res.

    (1998)
  • N.S. Dhalla et al.

    Cardiovasc. Res.

    (1998)
  • V. Panagia et al.

    Heart Failure Rev.

    (1997)

    • Cited by (0)

    1

    Present address: Division of Stroke and Vascular Disease, St. Boniface General Hospital Research Centre, Winnipeg, Manitoba, R2H 2A6, Canada.

    2

    To whom correspondence should be addressed at the Laboratory of Membrane Biology, Institute of Cardiovascular Sciences, St. Boniface General Hospital Research Centre, Room R3020, 351 Tache Ave., Winnipeg, MAN R2H 2A6, Canada. Fax: (204) 233-6723. E-mail: [email protected].

    View full text
    Copyright © 2000 Academic Press. All rights reserved.