In this study, we showed an increase in renal NNMT expression and NNMT-mediated changes in renal NAD + metabolites in a mouse model of renal fibrosis; renal NAD + salvage pathway metabolites, such as NAM, NMN, and NAD + , were diminished, while degradation products of NAM, such as MNA, N-Me-2PY, and N-Me-4PY, were increased in renal fibrosis. This evidence concerns the gene NNMT and renal fibrosis.