Opposite role of changes in mitochondrial membrane potential in different apoptotic processes

FEBS Letters

Franceschi, Claudio²  Pedrazzi, Jessica³  Salvioli, Stefano³  Pazienza, Teresa Loredana³  Barbi, Cristiana³  Cossarizza, Andrea³  Pinti, Marcello³  Dobrucki, Jurek¹  Moretti, Laura³  Bobyleva, Valentina³ 

[1] Laboratory of Confocal Microscopy and Image Analysis, Department of Biophysics, Jagiellonian University, Al. Mickiewicza 3, 31-120 Krakow, Poland;Department of Gerontological Sciences, INRCA, via Birarelli 8, 60121 Ancona, Italy;Department of Biomedical Sciences, Section of General Pathology, University of Modena and Reggio Emilia, via Campi 287, 41100 Modena, Italy

关键词: Mitochondrion;    Mitochondrial membrane potential;    Apoptosis;    Flow cytometry;    ΔΨ;    mitochondrial membrane potential;    JC-1;    5;    5′;    6;    6′-tetrachloro-1;    1′;    3;    3′-tetraethylbenzimidazolcarbocyanine iodide;    Val;    valinomycin;    TNF-α;    tumor necrosis factor-α;    PI;    propidium iodide;    CsA;    cyclosporin A;    MPT;    mitochondrial permeability transition;   

DOI  :  10.1016/S0014-5793(00)01266-7

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

We have studied the role of changes in mitochondrial membrane potential (ΔΨ) in two widely-used models of apoptosis, such as dexamethasone-treated rat thymocytes and U937 human cells treated with tumor necrosis factor-α and cycloheximide. To dissipate ΔΨ, we used low concentrations of valinomycin, unable per se to induce apoptosis, and demonstrated that the decline in ΔΨ exerts opposite effects in the two models. Indeed, in U937 cells, depolarization of mitochondria increased apoptosis, which decreased in rat thymocytes. This leads to the suggestion that disruption of ΔΨ plays opposite roles depending on the experimental model. In U937 cells, the drop of ΔΨ is a possible contributory cause for the apoptotic process; in rat thymocytes, it could be a limiting factor. We propose that these opposite effects could be due to the different ATP requirement of each apoptotic pathway.

【 授权许可】

Unknown