The transhydrogenation between NADH and NADP is coupled to respiration and ATP hydrolysis and functions as a proton pump across the membrane (By similarity). May play a role in reactive oxygen species (ROS) detoxification in the adrenal gland (By similarity). H(+)(in) + NAD(+) + NADPH = H(+)(out) + NADH + NADP(+) Homodimer. Widely expressed with expression most readily detectable in adrenal, heart, kidney, thyroid and adipose tissues. Higher levels of adrenocortical cell apoptosis and impaired glucocorticoid production are observed. In the N-terminal section; belongs to the AlaDH/PNT family. In the C-terminal section; belongs to the PNT beta subunit family.