ACTA ENDOCRINOLOGICA (BUC)

Background. sRANKL (soluble receptor activator of nuclear factor-kB ligand) and OPG (osteoprotegerin) represent a novel cytokine system with pleiotropic effects on bone remodeling.\r\nAim. The aim of this study was to assess the implications of serum levels of sRANKL, OPG and E2 (estradiol) in the process of bone remodeling of postmenopausal women with osteoporosis.\r\nMethods. The study was performed on 74 patients with postmenopausal osteoporosis, divided into two groups of patients according to the duration of estrogenic deprivation, compared with a control group (n= 20 postmenopausal women without osteoporosis). The serum levels of the enunciated markers were measured by ELISA technique.\r\nResults. In the group I (n= 48, bellow 15 yrs of estrogenic deprivation) the serum levels of sRANKL were 67.63?3.55 pg/mL (p<0.002), those of OPG were 42.15?0.55 pg/mL (p<0.002) and the levels of E2 were 28.32?1.78 pg/mL (p<0.004). In the group II (n= 26, over 15 yrs of estrogenic deprivation) the serum levels of sRANKL were 49.26?2.85 pg/mL (p<0.003), those of OPG 27.78?1.04 pg/mL (p<0.003) and the serum levels of E2 were 19.66?1.23 pg/mL (p<0.002). In the control group (n=20), the serum levels of sRANKL were 32.48?3.03 pg/mL, those of OPG 38.05?4.89 pg/mL and the serum levels of E2 were 43.07?4.04 pg/mL.\r\nConclusions. The serum levels of sRANKL are significantly higher in postmenopausal women with osteoporosis versus postmenopausal women without osteoporosis, attesting osteoclasts activation. The serum levels of OPG in postmenopausal women with osteoporosis were increased in group I, suggesting the osteoblastic activation and decreased in group II, probably secondary to the stimulation of osteoblastic apoptosis.

Aim. To assess the levels of s BGP and BAP and correlate them with the rate of bone remodelling.\r\nPatients and Methods. The study was performed on 74 cases with postmenopausal osteoporosis, divided into two groups, according to the duration of estrogenic deprivation, compared with a control group (n= 20, postmenopausal women without osteoporosis). The serum levels of the discussed markers were measured by ELISA technique. BMD was measured using the DXA technique with the assessment of T score.\r\nResults. In the group I: BGP were 20.12?0.87ng/mL (p<0.03), those of BAP 13.76?0.6&#956;g/mL (p<0.001) and sT spine were -3.63?0.65DS (p<0.001). In the group II: BGP were 15.12?1.55ng/mL (p<0.05), those of BAP 11.88?0.38&#956;g/mL (p<0.001) and sT spine were -3.78?0.36DS (p<0.001). The control group presented: BGP of 16.22?1.62ng/mL, those of BAP of 8.68?0.44&#956;g/mL and sT spine of -1.78?0.11DS. The serum levels of BGP in postmenopausal osteoporosis cases were increased in group I (suggesting an osteoblastic activation) and decreased in group II (probably secondary to the stimulation of osteoblastic apoptosis). The serum levels of BAP are significantly increased\r\nin postmenopausal osteoporosis versus control group, attesting osteoblastic activation.\r\nConclusion. Bone resorption begins gradually to outrun a new bone formation rhythm associated with low BMD.