Original Article

Biomechanical properties of osteoporotic rat femurs after different hormonal treatments: genistein, estradiol, and estradiol/progesterone

¹ Department of Orthopaedics and Traumatology, Dicle University, 2100 Diyarbakır, Turkey
² Department of Mechanical Engineering, TOBB University of Economics and Technology, 06560 Ankara, Turkey
³ Department of Orthopaedics, Göztepe Training and Research Hospital, 34888 İstanbul, Turkey
⁴ Department of Orthopaedics and Traumatology, Yenimahalle Training and Research Hospital, 0637 Ankara, Turkey

^* Corresponding author: ibrahimazboy@gmail.com

Received: 8 October 2015
Accepted: 22 March 2016

Abstract

Introduction: The purpose of the study is to compare the effects of genistein, estradiol, estradiol/progesterone combination on the bone mineral density and biomechanical properties of ovariectomized rats’ bone.

Methods: 50 female adult Sprague-Dawley rats were divided into five groups. Bilaterally ovaeriectomy were performed in all groups except the sham-operated group. Groups were a sham-operated group and a control group (water was given), estradiol treated group (17-β estradiol 0.015 mg/kg per day), genistein treated group (genistein 10 mg/kg per day), and an estradiol/progesterone combination group (17-β estradiol 0.015 mg/kg plus drosperinone 0.028 mg/kg per day). The water or hormones were implemented in relevant groups for eight weeks by orogasthric catheter. The bone mineral density and biomechanical properties of the femur were analyzed.

Results: Genistein, estradiol, and estradiol/progesterone groups increased bone mineral density significantly compared to the control group. In diaphysis and metaphysis bending test, all groups had higher peak load values than the control group. There were statistically significant differences between the estrogen/progesterone group and control group in diaphysis bending with regard to peak load. There were statistically significant differences between the estradiol and control groups in metaphysis bending with regard to peak load. In axial rotation test, all groups had higher peak torque values than the control groups.

Conclusions: Genistein, estradiol and estrogen/progesterone combination improved the biomechanical properties of the ovariectomized rat bone. Genistein which has less side effects may be considered as an alternative in the treatment of postmenopausal osteoporosis.