Effect of osteoporosis induced by ovariectomy on vertebral bone defect/fracture in rat.

Geng-Yang Shen,Hui Ren,Ting Qiu,Zhi-Dong Yang,Xiao-Bing Jiang,Zhen-Song Yao,Jin-Jing Huang,Xiang Yu,Zhi-Da Zhang,Wen-Hua Zhao,De Liang,Jing-Jing Tang

doi:10.18632/oncotarget.20611

Abstract

Osteoporotic vertebral fracture (OVF) is a worldwide health concern and lacks sufficient basic studies. Suitable animal models should be the foundation for basic study and treatment of OVF. There have been few studies on the development of animal models of osteoporotic vertebral bone defects. OVF models using various animal species should be developed to evaluate the therapeutic strategy in preclinical testing. We developed an OVF model in rats. Rat osteoporosis was induced by ovariectomy (OVX), and 3 months after OVX, a 3 mm diameter hemispheric vertebral bone defect was developed in lumbar vertebra 6 (L6). Sagittal plain X-rays of the rats, their bone quantity, bone microarchitecture, and histomorphology were analyzed: 3 months after OVX, rats showed significantly lower bone quantity, relative bone volume, and total volume bone mineral density. After the vertebral bone defect had developed for 16 weeks, no significant indication of self-healing could be observed from the sagittal plain X-rays, three-dimensional images, and histomorphology. These results indicate that the rat model of osteoporotic vertebral bone defect, induced by OVX and a 3 mm diameter hemispheric vertebral bone defect, can sufficiently mimic OVF patients in clinic and provide a sound basis for subsequent studies.

Highlights

Osteoporotic vertebral fracture (OVF), one of the most common complications of osteoporosis (OP), is associated with considerable disability and expense and increased risk of mortality [1, 2]; they are often asymptomatic when they first occur, with many cases going undiagnosed for a considerable time [3,4,5]
To verify the OP rat model, the levels of bone mineral density (BMD) and bone mineral content (BMC) were detected by dual-energy X-ray absorptiometry (DXA)
Suitable animal models are the foundation for studies of OVF treatment; for instance, they could allow access to new biological materials that could promote fracture healing through vertebroplasty or kyphoplasty [14, 15]

Summary

Introduction

Osteoporotic vertebral fracture (OVF), one of the most common complications of osteoporosis (OP), is associated with considerable disability and expense and increased risk of mortality [1, 2]; they are often asymptomatic when they first occur, with many cases going undiagnosed for a considerable time [3,4,5]. Basic studies of the development of animal models of osteoporotic vertebral bone defects that can sufficiently mimic OVF patients in clinical settings remain limited. The US Food and Drug Administration (FDA) established guidelines in 1994 indicating that novel protocols against OP should be evaluated using at least two animal species in preclinical testing. In response to this need for an effective animal model for the study of therapeutic strategies for the repair of OVF, such as biomaterial interventions, we developed an osteoporotic vertebral bone defect model in rats.

Methods

Results

Conclusion