Lecoeur Hervé, Langonné Alain, Baux Ludwig, Rebouillat Dominique, Rustin Pierre, Prévost Marie-Christine, Brenner Catherine, Edelman Léna, Jacotot Etienne
Theraptosis Research Laboratory, Theraptosis S.A., Institut Pasteur, 75015 Paris, France.
Exp Cell Res. 2004 Mar 10;294(1):106-17. doi: 10.1016/j.yexcr.2003.10.030.
Mitochondrial membrane permeabilization (MMP) is a key event in necrotic and (intrinsic) apoptotic processes. MMP is controlled by a few major rate-limiting events, one of which is opening of the permeability transition pore (PTP). Here we develop a flow cytometry (FC)-based approach to screen and study inducers and blockers of MMP in isolated mitochondria. Fixed-time and real-time FC permits to co-evaluate and order modifications of mitochondrial size, structure and inner membrane (IM) electrochemical potential (DeltaPsi(m)) during MMP. Calcium, a major PTP opener, and alamethicin, a PTP-independent MMP inducer, trigger significant mitochondrial forward scatter (FSC) increase and side scatter (SSC) decrease, correlating with spectrophotometrically detected swelling. FC-based fluorescence detection of the DeltaPsi(m)-sensitive cationic lipophilic dye JC-1 permits to detect DeltaPsi(m) variations induced by PTP openers or specific inducers of inner MMP such as carbonylcyanide m-chlorophenylhydrazone (mClCCP). These simple, highly sensitive and quantitative FC-based methods will be pertinent to evaluate compounds for their ability to control MMP.
