Abstract
Effects of CV-2619 and ubiquinone-10 (Q-10) on the energy metabolism of red blood cells (RBC) of Sprague Dawley rats were studied in the presence or absence of NaF. NaF (0.3-10 mM) dose-dependently decreased the ATP and lactate contents of the RBC. In the presence of NaF (1.5 DIM), ATP content decreased to about 30% of the control. Phosphofructokinase (PFK) was markedly activated, while glyceraldehydephosphate dehydrogenase (GAPDH) and enolase were inhibited by NaF. Thus, the decrease in ATP by NaF might be attributed to retarded glycolysis due to inhibition of the latter two enzymes. The decrease in ATP by NaF (1.5 mM) was dose-dependently inhibited by CV-2619 (0.3-30 μM). Inhibition of enolase and activation of PFK by NaF were still noted even in the presence of CV-2619. Inhibition of GAPDH by NaF, however, was released by CV-2619. Q-10 (1-100μM) did not affect the ATP levels decreased by NaF. It could be concluded that CV-2619 counteracted the NaF-induced decrease in the ATP level by accelerating the glycolytic flux through the GAPDH step, which was a rate-limiting one in the presence of NaF. Q-10, however, had no effect on the glycolytic flux.
