Regular Articles
Ischemic Loss of Sarcolemmal Dystrophin and Spectrin: Correlation with Myocardial Injury

https://doi.org/10.1006/jmcc.2001.1380Get rights and content

Abstract

Sarcolemmal blebbing and rupture are prominent features of irreversible ischemic myocardial injury. Dystrophin and spectrin are sarcolemmal structural proteins. Dystrophin links the transmembrane dystroglycan complex and extracellular laminin receptors to intracellular F-actin. Spectrin forms the backbone of the membrane skeleton confering an elastic modulus to the sarcolemmal membrane. An ischemic loss of membrane dystrophin and spectrin, in ischemically pelleted rabbit cardiomyocytes or in vivo 30–45 min permanently ischemic, LAD-ligated hearts, was detected by immunofluorescence with monoclonal antibodies. Western blots of light and heavy microsomal vesicles and Triton-extracted membrane fractions from ischemic myocytes demonstrated a rapid loss of dystrophin coincident with sub-sarcolemmal bleb formation, subsequent to a hypotonic challenge. The loss of spectrin from purified sarcolemma of autolysed rabbit heart, and both isolated membrane vesicles and Triton solubilized membrane fractions of ischemic cardiomyocytes correlated linearly with the onset of osmotic fragility as assessed by membrane rupture, subsequent to a hypotonic challenge. In contrast to the ischemic loss of dystrophin and spectrin from the membrane, the dystrophin-associated proteins, α -sarcoglycan and β -dystroglycan and the integral membrane protein, sodium-calcium exchanger, were maintained in the membrane fraction of ischemic cells as compared to oxygenated cells. Preconditioning protected cells, but did not significantly alter ischemic dystrophin or spectrin translocation. This previously unrecognized loss of sarcolemmal dystrophin and spectrin may be the molecular basis for sub-sarcolemmal bleb formation and membrane fragility during the transition from reversible to irreversible ischemic myocardial injury.

References (66)

  • SC Armstrong et al.

    Comparison of in vitro preconditioning responses of isolated pig and rabbit cardiomyocytes: effects of a protein phosphatase inhibitor, fostriecin

    J Mol Cell Cardiol

    (1997)
  • EK Iliodromitis et al.

    The PKC activator PMA preconditions rabbit heart in the presence of adenosine receptor blockade: Is 5-nucleotidase important?

    J Mol Cell Cardiol

    (1998)
  • Y Liu et al.

    Evidence that translocation of protein kinase C is a key event during ischemic preconditioning of rabbit myocardium

    J Mol Cell Cardiol

    (1994)
  • C Weinbrenner et al.

    Phosphorylation of tyrosine 182 of p38 mitogen-activated protein kinase correlates with the protection of preconditioning in the rabbit heart

    J Mol Cell Cardiol

    (1997)
  • H Ishihara et al.

    Calyculin A and okadaic acid: Inhibitors of protein phosphatase activity

    Biochem Biophys Res Comm

    (1989)
  • SC Armstrong et al.

    Phosphorylation state of hsp27 and p38 MAPK during preconditioning and protein phosphatase inhibitor protection of rabbit cardiomyocytes

    J Mol Cell Cardiol

    (1999)
  • SC Armstrong et al.

    Differential translocation or phosphorylation of alpha B crystallin cannot be detected in ischemically preconditioned rabbit cardiomyocytes

    J Mol Cell Cardiol

    (2000)
  • E Takashi et al.

    Pathologic assessment of myocardial cell necrosis and apoptosis after ischemia and reperfusion with molecular and morphological markers

    J Mol Cell Cardiol

    (2000)
  • Jennings, RB, Murry, C, Reimer, KA, Myocardial effects of brief periods of ischemia followed by reperfusion, In...
  • RB Jennings et al.

    Ischemic tissue injury

    Am J Pathol

    (1975)
  • MD Sage et al.

    Cytoskeletal injury and subsarcolemmal bleb formation in dog heart during in vitro total ischemia

    Am J Pathol

    (1988)
  • CJ Steenbergen et al.

    Volume regulation and plasma membrane injury in aerobic, anaerobic and ischemic myocardium in vitro. Effect of osmotic swelling on plasma membrane integrity

    Circ Res

    (1985)
  • CJ Steenbergen et al.

    Cytoskeletal damage during myocardial ischemia: Changes in vinculin immunofluorescence staining during totalin vitro ischemia in canine heart

    Circ Res

    (1987)
  • CE Ganote et al.

    Cellular swelling and irreversible myocardial injury: Effects of polyethylene glycol and mannitol in perfused rat hearts

    Am J Pathol

    (1977)
  • CE Ganote et al.

    Irreversible injury of isolated adult rat myocytes: Osmotic fragility during metabolic inhibition

    Am J Path

    (1988)
  • CE Ganote et al.

    Cytoskeletal lesions in anoxic myocardial injury: A conventional and high voltage electron microscopic and immunofluorescence study

    Amer J Pathol

    (1987)
  • CE Ganote et al.

    Ischemia and the myocyte cytoskeleton: Review and speculation

    Cardiovas Res

    (1993)
  • K Ohlendieck

    Towards an understanding of the dystrophin-glycoprotein complex: linkage between the extracellular matrix and the membrane cytoskeleton in muscle fibers

    Euro J Cell Biol

    (1996)
  • K Ohlendieck et al.

    Dystrophin–glycoprotein complex is highly enriched in isolated skeletal muscle sarcolemma

    J Cell Biol

    (1991)
  • A Menke et al.

    Decreased osmotic stability of dystrophin-less muscle cells from mdx mouse

    Nature

    (1991)
  • Y Ikeda et al.

    Altered membrane proteins and permeability correlate with cardiac dysfunction in cardiomyopathic hamsters

    Am J Physiol (Heart Circ Physiol)

    (2000)
  • V Bennett et al.

    The spectrin-based membrane skeleton and micro-scale organization of the plasma membrane

    Annu Rev Cell Biol

    (1993)
  • K Burridge et al.

    Nonerythrocyte spectrins: actin-membrane attachment proteins occurring in many cell types

    J Cell Biol

    (1982)
  • Cited by (0)

    Please address all correspondence to: Stephen C. Armstrong, Department of Pathology, P.O. Box 70568, James H. Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, USA. Tel: 423-439-6210; Fax: 423-439-8060;E-mail: [email protected]

    View full text