The Effects of TGF-ß3, 17-ß Estradiol and Bisphenol A on Osteoprotegerin Production in Osteoblasts

Abstract

Bone metabolism is a complicated and challenging issue in both physiological and pathological states. The homeostasis of the tissue is majorly being managed by the competing activities of osteoblasts and osteoclasts. Osteoprotegerin (OPG) is a decoy receptor for RANKL and it inhibits osteoclast differentiation by binding RANKL and being produced primarily by osteoblasts. The decrease in OPG level causes excessive osteoclast activation which results in high bone resorption that overcomes new bone formation. Therefore, it is important to understand the mechanism of OPG production and identify its regulators. In this study, it was aimed to address the effects of TGF-ß3, 17-ß estradiol and bisphenol A (BPA), an endocrine disrupter, on OPG production from osteoblasts. For this purpose, hfOB cells were treated with TGF-ß3, 17-ß estradiol and BPA for 48 hours both alone and in combinations. The effects of these agents were evaluated by sandwich-ELISA. The analysis showed that TGF-ß3 and 17-ß estradiol treatment causes an increase in OPG levels when used in combination. It was also discovered that BPA exhibits antagonistic effect on OPG production when used along with TGF-ß3 and 17-ß estradiol.