HMP Pathway Simplified: NADPH Role & G6PD Deficiency Explained Diabetes causes inhibition of glucose 6 phosphate dehydrogenase via activation of PKA, which contributes to oxidative stress in rat kidney cortex American Journal of Physiology Renal Physiology American Physiological Society Glucose 6 phosphate dehydrogenase deficiency Knowledge @ AMBOSS In G6PD deficiency (XR), we have increased oxidative damage to RBCs, leading to intravascular hemolysis with decreased serum haptoglobin. We have decreased NADPH production, which means decreased conversion of oxidized ( S S ) glutathione Glucose 6 Phosphate Dehydrogenase Deficiency (G6PD)