Effect of Vitamin D Treatment on Serum Sclerostin Level.

Objective Sclerostin is an osteocyte-secreted endogenous inhibitor of Wnt signaling. Several systemic and local factors have been suggested as possible regulators of sclerostin expression by osteocytes. In this study, we examined the effect of vitamin D treatment on sclerostin levels. Subject and Methods 44 patients with diagnosis of vitamin D deficiency (25(OH)D≤20 ng/ml) were involved in the study. Patients had monthly intramuscular injection of 300.000 IU cholecalciferol for 3 consecutive months. Sclerostin, 25(OH)D, parathyroid hormone (PTH), calcium, phosphorus and alkaline phosphatase (ALP) levels were measured during the diagnosis and after the replacement of vitamin D. Results 8 male and 36 female patients were enrolled in the study. Minimum age, maximum age and average age were 21, 55 and 32.02±9.26 years, respectively. A statistically significant difference was observed between the pre-treatment and post-treatment values in 25(OH)D levels (p:0.001, 10.27±4.62 ng/ml and 51.40±14.62 ng/ml, respectively), PTH levels (p:0.001, 50.32±19.05 pg/ml and 33.97±13.12 pg/ml, respectively) and sclerostin levels (p:0.002, 858.98±351.63 pg/ml and 689.52±197.92 pg/ml, respectively). No statistically significant difference, however, was found between the pre-treatment and post-treatment calcium, phosphorus and ALP levels. Correlation analysis made on pre-treatment and post-treatment sclerostin levels and 25(OH)D, PTH, calcium, phosphorus and ALP levels revealed no statistically significant correlation. Conclusion Our findings show that the sclerostin level of patients with vitamin D deficiency decreases considerably through treatment. © Georg Thieme Verlag KG Stuttgart · New York.