Figure 2.

Mitochondrial and cytosolic NAD pools communicate via MAS

(A) Summarized data showing time-dependent changes of mitochondrial (mt-SoNar, blue) or cytosolic (ct-SoNar, red) NAD⁺/NADH ratio in response to acute addition of 1 mM pyruvate. n = 5 rats.

(B) Mitochondrial or cytosolic NAD⁺/NADH ratio in response to acute addition of 20 mM glucose. n = 4–5 rats. ∗p < 0.05 versus control (value is set as 1.0).

(C) Changes of mitochondrial or cytosolic NAD⁺/NADH ratio in response to acute addition of 5 μM rotenone. n = 4-5 rats. ∗p < 0.05 versus control (value is set as 1.0).

(D) Schematic model showing the regulation of mitochondrial and cytosolic NAD pools and their connection via MAS.

(E and F) Effects of 400 μM AOA and/or 1 μM FCCP preincubation on pyruvate-induced changes of NAD⁺/NADH ratio in the mitochondria (E) or cytosol (F) of adult cardiomyocytes. n = 4–6 rats. ∗p < 0.05 versus control (value is set as 1.0); ^#p < 0.05 versus pyruvate + FCCP.

(G) Effects of AOA on cytosolic or mitochondrial NAD⁺/NADH ratios in adult cardiomyocytes (ACM) or A549 cells. n = 4–5. ∗p < 0.05 versus control (value is set as 1.0).

(H) Summarized data showing time-dependent changes of cytosolic NAD⁺/NADH ratio in adult cardiomyocytes or A549 cells by 1 mM pyruvate with or without 400 μM AOA preincubation. n = 4–5.

(I) Effects of AOA on the recovery rate of cytosolic NAD⁺/NADH ratio after the pyruvate-induced peak changes in adult cardiomyocytes or A549 cells. n = 4–5. ^#p < 0.05 versus −AOA.

Data are presented as mean ± SEM.