Preclinical studies demonstrated that klotho has cardio protective effect. One important biological function of Klotho is to maintain mineral homeostasis, which is both fibro blast growth factor-23 (FGF23)-dependent and FGF23-independent.

Aims: to study the relation between serum soluble klotho (sKlotho) and the following cardiovascular parameters; valvular calcification, vascular calcification, pulmonary hypertension (PH) and left ventricular hypertrophy (LVH). Also, we studied the relation between sklotho andbone mineral density (BMD) as well as serum ferritin.

Methods: 40 hemodialysis (HD) patients were recruited from Minia University Hospital dialysis center as well as 20 healthy controls participated in this study. sklotho,  FGF-23, sclerostin, 25-OH-D, iPTH, and ferrit in were measured. High resolution peripheral quantitative computed tomography (HR-pQCT) was used to measure BMD. Multi-detector computed tomography (MDCT) was used to detect aortic calcification. Transthoracic echocardiography was used to detect LVH, PH, and valvular calcifications.

Results: sklotho level was significantly lower in HD patients than controls. In significant deffirences in sklotho levels between patients with and without PH and between patients with and without LVH. However, patients with higher sklotho had a trend toward protection from valvular and vascular calcification. There was a positive correlation between sklotho and  25-OH- D (r = 0.359, p = 0.023), and serum corrected total calcium (r = 0.956, p < 0.001). Mean while, there was a negative correlation between sklotho and BMD (r = -0.425, p = 0.006), FGF-23 (r = -0.375, p = 0.017),  sclerostin (r = -0.445, p = 0.004), phosphorus (r = -0.859, p< 0.001). We found also that sklothois negatively correlated with serum ferritin in healthy controls and this correlation was disrupted in HD patients.

Conclusions: Higher sklotho was associated with decreased BMD, and a trend toward absence ofaortic and valvular calcifications in HD patients.

Keywords: sklotho, PH, LVH, aortic and valvular calcifications, BMD.

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Hesham K H Keryakos

Division of Nephrology, Department of Internal Medicine,

Faculty of Medicine, Minia, Egypt

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