FGF23 and Marchiafava-Bignami disease: Adenine mice displayed elevated serum phosphate, intact parathyroid hormone (iPTH) and FGF23, and decreased 1,25-dihydroxyvitamin D3 (1,25 (OH)2D3) (Fig. 2A) - the characteristic serological changes of CKD-MBD that causally related to bone damage.