purine nucleotide catabolic process pyridine nucleotide catabolic process NAD+ metabolic process NAD+ catabolic process https://github.com/geneontology/go-ontology/issues/21577 https://github.com/geneontology/go-ontology/issues/29050 https://github.com/geneontology/go-ontology/issues/29666 NADH catabolic process reduced NAD catabolic process nicotinamide adenine dinucleotide catabolism oxidized NAD catabolic process NAD (oxidized) catabolic process reduced NAD catabolism GO:0019677 GO:0006737 NAD catabolism NAD catabolic process NAD (oxidized) catabolism The chemical reactions and pathways resulting in the breakdown of nicotinamide adenine dinucleotide (NAD+), a coenzyme that interconverts with its reduced form, NADH, in many redox and catabolic reactions. oxidized nicotinamide adenine dinucleotide catabolic process biological_process NAD degradation oxidized NAD catabolism reduced nicotinamide adenine dinucleotide catabolic process NAD (reduced) catabolic process NAD (reduced) catabolism oxidized nicotinamide adenine dinucleotide catabolism nicotinamide adenine dinucleotide catabolic process NADH catabolism reduced nicotinamide adenine dinucleotide catabolism NAD breakdown