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