Mitochondria are selective targets for the protective effects of heat shock against oxidative injury.
Heat shock (HS) proteins (HSPs) induce protection against a number of stresses distinct from HS, including reactive oxygen species. In the human premonocytic line U937, we investigated in whole cells the effects of preexposure to HS and exposure to hydrogen peroxide (H2O2) on mitochondrial membrane potential, mass, and ultrastructure. HS prevented H2O2-induced alterations in mitochondrial membrane potential and cristae formation while increasing expression of HSPs and the protein product of bcl-2. Protection correlated best with the expression of the 70-kDa HSP, hsp70. We propose that mitochondria represent a selective target for HS-mediated protection against oxidative injury.
Polla
B S
BS
Laboratoire de Physiologie Respiratoire, Unité de Formation et de Recherche Cochin Port-Royal, Paris, France.
Kantengwa
S
S
François
D
D
Salvioli
S
S
Franceschi
C
C
Marsac
C
C
Cossarizza
A
A
D017209:Apoptosis / Q000235:genetics; D002460:Cell Line; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics / Q000502:physiology*; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D007425:Intracellular Membranes / Q000502:physiology; D008564:Membrane Potentials; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology; D016877:Oxidants; D018384:Oxidative Stress; D011518:Proto-Oncogene Proteins / Q000235:genetics; D019253:Proto-Oncogene Proteins c-bcl-2
D018840:HSP70 Heat-Shock Proteins; D016877:Oxidants; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D006861:Hydrogen Peroxide