Diagnostic potential of increased Klotho and FGF23 protein concentrations after myocardial infarction in patients with acute coronary syndrome.

Background: Klotho is a transmembrane and secretory protein and acts as a co-receptor for fibroblast growth factor 23 (FGF23). This study aimed to analyse the concentration of Klotho and FGF23 proteins in patients with myocardial infarction (MI).

Methods: The study group comprised 129 patients diagnosed with acute coronary syndrome (ACS), who were referred for further invasive diagnostics (MI group). Blood samples were collected at 4 time points: at admission, and 6h, 24h, and between 24-48h post-admission. The criteria for the control subjects (n = 30) were no declaration of MI and ACS (non-MI group). Klotho and FGF23 concentrations in plasma were tested by ELISA at each time point.

Results: The concentration of soluble Klotho in the MI group was increased at admission, 6h and 24 h post-admission, and then normalized at 24-48h. Klotho concentration was also significantly increased in patients with ST-segment elevation MI (STEMI) only at admission, in comparison to non-ST-segment elevation MI (NSTEMI). The concentration of FGF23 in the MI group was higher at admission, 6h and 24h post-admission, and continued to increase after 24-48 h. There was an increase in FGF23 concentration in the STEMI group at 24-48h post-admission, in comparison to NSTEMI.

Conclusions: The concentrations of Klotho and FGF23 in plasma were higher in patients with MI and changed over time. Thus, Klotho and FGF23 may be recognized as new factors in the diagnosis and/or monitoring of ACS, as well as novel therapeutic targets.