More importantly, LCN2 administration to CPD mice increased bone Fgf23 mRNA and both serum cFGF23 and iFGF23 levels to similar levels observed in control Col4a3KO mice (Fig. 3m–o), showing that increased LCN2 levels contribute to increased FGF23 production in CKD. Here, LCN2 is linked to chronic kidney disease.