Relevancy of blood specimen-molecular biomarkers in studying osteoporosis in postmenopausal women

Background. Osteoporosis is a bone disease characterized by low bone mass and micro-architectural weakening of bone tissue. It can be influenced, in part, by immunological activity. Therapeutically targeting immune factors that promote osteoporosis could protect a larger number of susceptible individuals, especially postmenopausal women, from this debilitating disease. The aim of the present study is to evaluate blood levels of gene expression for RANKL, RANK, OPG, OSCAR, and the transcription factors RORᵧt and FOXP3 (as representatives of Th17 and Treg cells, respectively) to determine their potential as biomarkers for detecting postmenopausal osteoporosis. Methods. A total of 88 postmenopausal women were included in this study: 43 women with osteoporosis (PO group), 45 women without osteoporosis (PNO group) as age-matched controls, and 40 young healthy females as baseline controls (YA group). Blood samples were collected from all participants to assess gene expression levels of the factors of interest using qRT-PCR. Results. There was a non-significant increase in RANKL expression in the PO group compared to the PNO and YA groups (PO=1.68, PNO=1.53, YA=1.0). The Th17 population was significantly elevated in the PO group compared to the YA group (PO=1.53, YA=1.0). No statistical differences were observed among the groups for the other genes. Conclusion. Th17 is a prominent osteoclastogenic marker detected in the blood. Although RANKL is a crucial factor in bone resorption, its expression level in the blood of postmenopausal women with osteoporosis appears to be inconclusive.