Serum sirtuin 1 is independently associated with intact PTH among patients with chronic kidney disease

Background: Sirtuin 1 is involved in the pathogenesis of age-related diseases. Purpose: The aim of the study was to assess the clinical and diagnostic value of serum sirtuin 1 concentration in patients with CKD. Patients and Methods: The serum sirtuin 1 level was evaluated using ELISA kit in 100 CKD patients stratified for five stages and in a control group of 24 healthy volunteers. Results: Serum sirtuin 1 concentration was higher in the CKD group compared with the control group (p< 0.05). Sirtuin 1 correlated with conventional CKD biomarkers and eGFR equations, intact parathyroid hormone (iPTH) and age (all p< 0.05). Statins, AT 1 receptor antagonists and β-blockers use were associated with decreased sirtuin concentration (p< 0.05). Sirtuin 1 was able to distinguish CKD from control group with high sensitivity and specificity (93% and 87%, respectively; AUC=0.954). Surprisingly, after adjustment only iPTH concentration was an independent predictor of sirtuin 1 level. Conclusion: The association between sirtuin 1, eGFR equations and iPTH indicates its possible usefulness as a kidney function marker. In terms of iPTH being the only independent predictor of circulating sirtuin 1 it can be considered as an indirect cardiovascular risk biomarker regardless of renal function and provide additional information for patient management. Alternatively, sirtuin 1 is recognized as protective against vascular disease, and we demonstrated a positive correlation with iPTH, which may be related to accumulation of (7-84)-PTH having opposite biological effects to full-length PTH. Further studies are needed to explore the interplay between sirtuin 1, PTH and CKD-related vascular calcification as well as to assess its prognostic value in observational studies.