Maria Rosaria Povino

Publications (2)8.42 Total impact

• Article: Dose-Dependent Short-Term Effects of Single High Doses of Oral Vitamin D(3) on Bone Turnover Markers.

  Maurizio Rossini, Silvano Adami, Ombretta Viapiana, Elena Fracassi, Luca Idolazzi, Maria Rosaria Povino, Davide Gatti
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  ABSTRACT: We investigated the short-term effects on bone turnover markers of high doses of vitamin D(3) in order to identify what initial therapeutic dose can be safely administered in vitamin D-deficient subjects. Thirty-seven elderly subjects [mean age 75 ± 3 (SD) years] were consecutively randomized to the administration of a single oral bolus of 600000, 300000, or 100000 IU vitamin D(3). Blood samples were taken at baseline and 1, 3, 7, 14, 30, 60, and 90 days after vitamin D(3) administration. Twenty-four subjects served as controls. No relevant changes in bone turnover markers [C-terminal telopeptides of type I collagen (sCTX) and bone-specific alkaline phosphatase (BAP)] were observed in the controls. In treated patients a dose-dependent effect on sCTX was observed. With the administration of 600,000 IU vitamin D(3) a significant increase of sCTX was observed already at day 1, and it was sustained for 2 months. The changes in sCTX with smaller doses were considerably lower and reached statistical significance only within the first 3 days with the 300,000 IU dose. BAP remained unchanged in patients given 300,000 and 600,000 IU vitamin D(3), while it significantly rose by 15-23 % throughout the observation period in patients given 100,000 IU. Our results indicate that the use of a vitamin D bolus exceeding 100,000 IU may be associated with acute increases of sCTX.
  Calcified Tissue International 09/2012; · 2.38 Impact Factor
• Article: Sclerostin and DKK1 in postmenopausal osteoporosis treated with denosumab.

  Davide Gatti, Ombretta Viapiana, Elena Fracassi, Luca Idolazzi, Carmela Dartizio, Maria Rosaria Povino, Silvano Adami, Maurizio Rossini
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  ABSTRACT: The bone mass benefits of antiresorbers in postmenopausal osteoporosis are limited by the rapid coupling of decreasing bone resorption with bone formation. Wnt signaling is involved in this coupling process during treatment with bisphosphonates, whereas its role during treatment with the anti-receptor activator of NF-κB ligand (RANKL) antibody denosumab is unknown. The study population includes patients participating in a placebo-controlled trial lasting 36 months: 19 women were on placebo and 24 on subcutaneous 60 mg denosumab every 6 months. All measured parameters (serum C-terminal telopeptide of type I collagen [sCTX], serum bone alkaline phosphatase [bAP], Dickkopf-1 [DKK1], and sclerostin) remained unchanged during the observation period in the placebo group. sCTX and bAP were significantly suppressed by denosumab treatment over the entire follow-up. Denosumab treatment was associated with significant (p < 0.05) increases (28% to 32%) in serum sclerostin over the entire study follow-up. Serum DKK1 significantly decreased within the first 6 months with a trend for further continuous decreases, which reached statistical significance (p < 0.05) versus placebo group from the 18th month onward. The changes in DKK1 were significantly and positively related with the changes in sCTX and bAP and negatively with hip bone mineral density (BMD) changes. The changes in sclerostin were significantly and negatively related only with those of bAP. The changes in bone turnover markers associated with denosumab treatment of postmenopausal osteoporosis is associated with significant increase in sclerostin similar to those seen after long-term treatment with bisphosphonates and significant decrease in DKK1. This latter observation might explain the continuous increase over 5 years in BMD observed during treatment of postmenopausal osteoporosis with denosumab. © 2012 American Society for Bone and Mineral Research.
  Journal of bone and mineral research: the official journal of the American Society for Bone and Mineral Research 06/2012; 27(11):2259-63. · 6.04 Impact Factor