Fig 5. Disulfiram impedes mitochondrial respiration.

Mitochondria were pre-incubated with disulfiram (100 μM) and the different states of respiration were measured. State 2 respiration was induced by the addition of pyruvate/malate (A), succinate (B), or palmitoyl-carnitine (C). The final concentration of pyruvate/malate, succinate, or palmitoyl-carnitine was 10 mM/2 mM, 5 mM, and 50 μM, respectively. State 3 (phosphorylating respiration) and state 4 (proton leak-dependent respiration) were induced by addition ADP (1 mM) and oligomycin (4 μg/mL) to the chamber. Antimycin A was then added to assess O₂ consumption not associated with the respiratory chain. All respiration values were corrected for O₂ consumption not associated with the electron transport chain. (D) Membrane potential determinations were conducted on mitochondria treated with disulfiram (100–500 μM) and TMRE (10 nM). The final concentration of pyruvate, succinate, or palmitoyl-carnitine was 50 μM. For experiments with pyruvate, malate was also included in the reaction mixture at a final concentration of 50 μM. In palmitoyl-carnitine expeirments, mitochondria were pre-incubated in basic medium containing 2 mM carnitine. * corresponds to significance when compared to state 4 control. # corresponds to significance when comparing control to disulfiram during state 3 or 4 respiration. n = 4, mean±SEM.