Bone Abstracts

Circulating microRNAs (miRNAs) are currently being investigated as novel biomarkers for osteoporosis and osteoporotic fractures. The aim of the present study was to investigate the differential expression of specific circulating micro RNAs known to regulate bone metabolism and homeostasis in postmenopausal osteoporotic women with and without vertebral fractures. For the analysis, miRNAs were isolated from the serum of 24 osteoporotic patients with at least one moderate vertebral fracture and 24 osteoporotic women without vertebral fractures. Twenty postmenopausal women with normal BMD and with no previous history of any kind of fracture were also included in the analysis as controls. From the 14 miRNAs that were selected we identified seven miRs, namely miR-21, miR-23a, miR-124, miR-2861, miR-29a, miR-29b, miR-29c that were significantly deregulated in the serum of osteoporotic patients compared to controls. Two of them (miR-124 and miR-2861) were significantly upregulated while miR-21, miR23a, miR29a, miR29b and miR-29c demonstrated a significantly lower expression in the serum of osteoporotic patients compared to controls. In the sub-group analysis in the osteoporotic group of patients, miR-21, miR-29a, miR-29b and miR-29c were significantly lower in osteoporotic fractured patients compared to osteoporotic patients without fractures. MiR-218, was upregulated in the fractured osteoporotic patients compare to non-fractured, but without reaching statistical significance. This study shows that the expression pattern of specific miRNAs in the serum of osteoporotic patients at increased risk for vertebral fractures may be used as a diagnostic tool for further optimizing fracture risk assessment.