Fig. 2.
APC- and DNP- induced mitochondrial depolarization in cardiomyocytes is reversed by pyruvate. Mitochondrial membrane potential was assessed by fluorescence of flavoproteins (FPs) and TMRE. A: the ability of pyruvate to increase the ΔΨm was demonstrated after the addition of 250 μM pyruvate. Following a transient FP oxidation and a decrease in ΔΨm, pyruvate induced a sustained FP reduction and mitochondrial hyperpolarization. B and C: APC and DNP (200 nM) increased FP and decreased TMRE fluorescence intensities compared with control. Addition of low concentration of pyruvate (2 μM) reversed the effects of APC and DNP, while pyruvate alone slightly hyperpolarized mitochondria. Data are means ± SE; n = 7–8/group. *P < 0.05 vs. Ctrl; #P < 0.05 APC or DNP vs. APC + Pyr or DNP + Pyr, respectively.