|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1Department of Pathology, John D. Dingell Veterans Affairs Medical Center, and Departments of 2Pathology and 3Medicine, Wayne State University Medical School, Detroit, Michigan
Submitted 8 February 2006 ; accepted in final form 8 March 2006
To define better the subcellular mechanism of heat shock (HS)-induced cardioprotection, we examined the effect of HS, as well as selective expression of individual HS proteins (HSPs), on cell injury in neonatal rat ventricular myocytes (NRVM). HS was induced in NRVM by a rapid elevation of temperature to 42°C for 20 min followed by 2024 h of recovery at 37°C. Other NRVM were infected with a replication-deficient adenovirus encoding HSP27 or HSP70. On the same day, all groups were subjected to metabolic inhibition (MI). Cell injury was assayed by measurement of the percentage of total lactate dehydrogenase released, the percentage of cells staining with trypan blue, or TdT-mediated dUTP nick-end labeling, whereas cell signaling was assayed by immunoblot analysis and coimmunoprecipitation. Before MI, the viability of all treated groups did not differ significantly from control NRVM. HS resulted in a significant increase in HSP70 and HSP27 expression. Infection with either virus caused a significant increase in selective HSP content compared with control NRVM. HS protected NRVM from injury. Selective expression of HSP27 or HSP70 alone was not protective in NRVM, but dual infection with both viral vectors (HSP27 + HSP70) was protective. HS and HSP27 + HSP70 expression caused increased paxillin localization in the membrane fraction, which persisted in response to MI, compared with control NRVM. HS increased the integrin-paxillin-focal adhesion kinase interaction, whereas targeted inhibition of focal adhesion kinase activity abolished the integrin-paxillin association and resulted in an increase in cell death. HS and HSP27 + HSP70 expression increased the association of members of the focal adhesion complex and protected NRVM against irreversible injury. Cytoskeletal-based signaling pathways at focal adhesion junctions may represent a unique pathway of cardioprotection.
heat shock protein; neonatal rat ventricular myocytes; metabolic inhibition
This article has been cited by other articles:
![]() |
H. Wei and R. S. Vander Heide Heat stress activates AKT via focal adhesion kinase-mediated pathway in neonatal rat ventricular myocytes Am J Physiol Heart Circ Physiol, August 1, 2008; 295(2): H561 - H568. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |