Tumor necrosis factor-alpha and tumor necrosis factor receptor-1 in postmenopausal osteoporosis: relation to serum estradiol

ABSTRACT

To measure serum levels of TNF-alpha and TNFR-1 in women with postmenopausal osteoporosis and correlate them with serum level of estradiol. This study was conducted on 26 postmenopausal females. They were divided according to their BMD into two groups. Group [I] consisted of 16 patients with osteoporosis [T score < -2.5] and group [II] consisted of 10 patients with osteopenia [T score -1 to -2.5]. Ten healthy postmenopausal women with normal range of BMD [T score >-1] served as control group. The serum levels of TNF-alpha TNFR-1 were measured with ELISA and serum estradiol was determined with electrochemiluminescence immunoassay [ECLIA]. Bone mineral density was measured with dual-energy x-ray absorptiometry. Serum estradiol level was significantly lower in both osteoporotic [7.88 +/- 3.14pg/ml] and osteopenic patients [8.54 +/- 3.99 pg/ml] as compared to controls [13.62 +/- 4.57 pg/ml]. Serum level of TNF-alpha and TNFR-1 were insignificantly highest among osteoporotic patients as compared to osteopenic patients and controls. There was no significant correlation between estradiol and TNF-alpha or TNFR-1 [r=0.12, p>0.05 and r=0.07, p>0.05] respectively. A significant negative correlation was found between femoral BMD of patients and serum TNF-alpha [r=-0.43, p<0.05] and TNFR-1 [r=-0.47, p<0.05]. TNF-alpha also showed significant positive correlation with weight [r= 0.41, p<0.05] as well as the BMI [r=0.44, p<0.05]. TNF-alpha has a role in the pathogenesis of postmenopausal osteoporosis, which seems to be independent of estradiol and may thus be a novel target for therapy in resistant cases of postmenopausal osteoporosis