Catalyzes the conversion of monodehydroascorbate to ascorbate, oxidizing NADH in the process. Ascorbate is a major antioxidant against reactive oxygen species (ROS) and nitric oxide (NO) (PubMed:24376554, PubMed:27652777). Can use NADPH as electron donor, but possesses lower activity compared to NADH as electron donor (PubMed:27652777). H(+) + 2 monodehydro-L-ascorbate radical + NADH = 2 L-ascorbate + NAD(+) Down-regulated during senescence. Belongs to the FAD-dependent oxidoreductase family.