NNT (Nicotinamide Nucleotide Transhydrogenase): Nicotinamide Nucleotide Transhydrogenase (NNT) is an enzyme found in the inner mitochondrial membrane that plays a crucial role in regenerating NADPH from NADH. This process is vital for maintaining the cellular redox balance and protecting cells against oxidative stress. Deficiencies in NNT can compromise mitochondrial function and heighten susceptibility to oxidative damage, contributing to metabolic disorders and chronic illnesses.