Effects of pentoxifylline and alendronate on fracture healing in ovariectomy-induced osteoporosis in rats

Document Type : Original Article


1 Department of Basic Sciences, School of Allied Medical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran

2 Department of Biology and Anatomical Sciences, School of Medicine, Shahid Beheshti University of Medical Science, Tehran, Iran

3 Cellular and Molecular Research Center, Shahrekord University of Medical Sciences, Shahrekord, Iran

4 Department of Statistics, Faculty of Sciences, University of Qom, Qom, Iran

5 Department of Internal Medicine, Aurora Medical Center- Bay Area, Marinette, Wisconsin, USA

6 Price Institute of Surgical Research, University of Louisville, Noveratech LLC of Louisville, Louisville, USA

7 Department of Anatomy, School of Medicine, Tehran Medical Sciences Branch, Islamic Azad University, Tehran, Iran

8 Cellular and Molecular Biology Research Center, Department of Biology and Anatomical Sciences, Shahid Beheshti University of Medical Science, Tehran, Iran


Osteoporosis is determined by decreased bone strength that increases the threat of fractures. The aim of this study was to evaluate the effects of pentoxifylline (PTX) and alendronate (ALN), on the stereological parameters, and gene expression in callus of fracture in an experimental rat model of ovariectomy-induced osteoporosis (OVX). The OVX was induced in 90 female rats. Fourteen weeks later, a complete fracture on the right femur was made. Rats were divided into five groups: 1) control: no treatment; 2) sham: received daily distilled water; 3) daily 3.00 mg kg-1 ALN subcutaneously (SC); 4) daily 200 mg kg-1 PTX (SC) and 5) daily PTX (SC) + ALN (same doses). The osteoclast count was significantly lower in all treatment groups, at 21 and 56 days post-surgery, compared to the control and sham groups. The PTX significantly increased total callus volume at 21 and 56 days post-surgery, compared to the other groups. The PTX+ALN treatment significantly increased both cortical bone volume on day 21, and osteocyte and osteoblast numbers on day 56, compared to the control and sham groups. It can be concluded that PTX and ALN have antiresorptive effects, in OVX rats. Also, PTX has increased the extracellular matrix on both 21 and 56 days after surgery, compared to the other groups. PTX+ALN elevated cortical bone volume on day 21, and osteocyte and osteoblast numbers compared to the control and sham groups on day 56.


Main Subjects


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Volume 10, Issue 2
June 2019
Pages 93-100
  • Receive Date: 12 March 2018
  • Revise Date: 01 July 2018
  • Accept Date: 01 August 2018
  • First Publish Date: 01 June 2019