The Role of Serum Osteopontin Levels in Egyptian Women With Postmenopausal Osteoporosis

Abstract

Background: Postmenopausal osteoporosis (PMO) is a debilitating disease induced by estrogen deficiency characterized by bone loss and bone micro-architecture degradation contributing to fragility fractures. Osteopontin (OPN) has been found to be involved in bone turnover by activating the resorption process. Objectives: This study aim to evaluate the relationship between serum OPN levels and bone mineral density (BMD) for identification of female individuals at high risk of osteoporotic fractures. Methods: A total of eighty eight postmenopausal women (PMW) were recruited in this study. Densitometry results addressed cases of the study into 3 groups: thirty with osteoporosis, thirty with osteopenia and twenty eight PMW without complications as a control group. Serum OPN was measured by using Enzyme-Linked immunosorbent assay (ELISA) kits and BMD was obtained at lumbar spine and femoral neck by dualenergy X-ray absorptiometry (DEXA). Results: Osteopontin levels were significantly higher in osteoporotic group compared to osteopenic and control groups (P ˂ 0.001). Negative correlation was found between BMD and OPN in osteoporotic group. By using the Receiver Operating Characteristic (ROC) curve, the cutoff level of ≥ 10.294 ng/mL for OPN was chosen for suggesting osteoporosis which yield a sensitivity of 66.67 % and specificity of 96.43 %. Also, there were a significant increase in serum ALP levels in osteoporotic and osteopenic groups compared to control group while serum Ca failed to show a significant difference between the studied groups. In addition, serum TAC showed a significant decrease in osteoporotic group compared to control group. Conclusion: These findings suggest that the circulating OPN might play role in the pathophysiology of PMO. Its blood concentration can be used as a sensitive monitoring indicator for the early detection of osteoporosis independently of BMD.

The Value of Osteopontin as a Diagnostic Biomarker in Postmenopausal Osteoporosis; A Review.

“…Studies have demonstrated that estrogen deficiency reduces bone formation and bone mass, these collagenous matrix protein ''Osteopontin''. Elevated OPN levels have been reported in patients with increased bone resorption, these data point toward a specific pathophysiological role of OPN in osteoporosis [20,21,30,60,62,69].…”