Pharmacological screening and enzymatic assays for apoptosis.
Mitochondria play a central role in the intrinsic pathway of apoptosis. In response to many pro-apoptotic stimuli, mitochondria undergo an irreversible process called mitochondrial membrane permeabilization (MMP). The detection of MMP in isolated mitochondria is most often based on assays that monitor either the loss of the inner transmembrane potential (DYm; classically with Rhodamine 123), permeability transition (PT, cyclosporin A-sensitive matrix swelling), or the release of critical pro-apoptotic intermembrane space effectors. To gain complementary information on MMP mechanisms, we have systematically used three additional assays optimized for the 96-well microplate format: (1) inner membrane permeability, (2) VDAC-associated NADH reductase activity, and (3) ATP/ADP translocase activity. We report that ad hoc combinations of ANT and VDAC ligands, carbonyl cyanide m-chlorophenylhydrazone (CCCP), mastoparan and Vpr52-96 peptide and PT inhibitors, permit to explore relationships between enzymatic functions of sessile mitochondrial proteins (i.e. ANT, VDAC) and MMP. These assays should be useful tools to investigate mitochondrial apoptosis, decipher the implication of inner and outer membrane permeabilization and provide a multi-parametric approach for drug discovery.
Belzacq-Casagrande
Anne-Sophie
AS
University of Versailles/SQY, PRES UniverSud Paris, CNRS UMR 8159, Versailles, France.
Martel
Cecile
C
Pertuiset
Claire
C
Borgne-Sanchez
Annie
A
Jacotot
Etienne
E
Brenner
Catherine
C
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D002118:Calcium / Q000494:pharmacology; D002463:Cell Membrane Permeability / Q000187:drug effects; D051379:Mice; D008930:Mitochondria, Liver / Q000187:drug effects / Q000648:ultrastructure; D008933:Mitochondrial Swelling / Q000187:drug effects; D054325:vpr Gene Products, Human Immunodeficiency Virus / Q000494:pharmacology
D054325:vpr Gene Products, Human Immunodeficiency Virus; C514912:vpr protein, Human immunodeficiency virus 1; D002118:Calcium