Klotho is upregulated in human cardiomyopathy independently of circulating Klotho levels.

Klotho is an antiaging protein which exerts known cardioprotection. In kidney, trans-membrane Klotho acts as essential co-receptor of fibroblast growth factor 23 (FGF23). In the heart, soluble Klotho (sKlotho) protects from systolic dysfunction independently of FGF23.

FGF23 is associated with disease severity and prognosis in chronic heart failure.

Background: Elevated levels of fibroblast growth factor 23 (FGF23) are associated with incident heart failure in individuals with or without chronic kidney disease. We aimed to investigate the association between serum FGF23 concentrations and disease severity and long-term outcome in patients with stable heart failure.

Materials And Methods: Serum levels of C-term FGF23 (Ct-FGF23) concentrations, inorganic phosphate (Pi ), parathormone (PTH) and 25-hydroxyvitamin D (25(OH)D) were measured in 208 patients with nonischaemic heart failure (age 48 ± 15 years; 70% male; NYHA Class I 27·8%, NYHA Class II 43·4%, NYHA Class III/IV 28·8%; LV-EF 34 ± 15%; eGFR ≥60 mL/min/1·73 m(2) in 86%).