The influence of estrogen deficiency on the structural and mechanical properties of rat cortical bone

PeerJ

article

Anna Shipov¹  Paul Zaslansky²  Heinrich Riesemeier³  Gilad Segev¹  Ayelet Atkins⁴  Noga Kalish-Achrai¹  Stephen Weiner⁵  Ron Shahar¹ 

[1]Koret School of Veterinary Medicine, The Hebrew University of Jerusalem

[2]Department for Operative and Preventive Dentistry. Centrum für Zahn-, Mund- und Kieferheilkunde, Charité - Universitätsmedizin Berlin

[3]BAM Federal Institute for Materials Research and Testing

[4]Department of Chemistry and Bar Ilan Institute of Nanotechnology and Advanced Materials ,(BINA), Bar-Ilan University

[5]Department of Structural Biology, Weizmann Institute of Science

关键词: Estrogen;    Disorganized bone;    Rat;    Lacunae;    Ovariectomy;   

DOI  :  10.7717/peerj.10213

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

BackgroundPost-menopausal osteoporosis is a common health problem worldwide, most commonly caused by estrogen deficiency. Most of the information regarding the skeletal effects of this disease relates to trabecular bone, while cortical bone is less studied. The purpose of this study was to evaluate the influence of estrogen deficiency on the structure and mechanical properties of cortical bone.MethodsEight ovariectomized (OVH) and eight intact (control) Sprague Dawley rats were used.Structural features of femoral cortical bone were studied by light microscopy, scanning electron microscopy and synchrotron-based microcomputer-tomography and their mechanical properties determined by nano-indentation.ResultsCortical bone of both study groups contains two distinct regions: organized circumferential lamellae and disordered bone with highly mineralized cartilaginous islands. Lacunar volume was lower in the OVH group both in the lamellar and disorganized regions (182 ± 75 µm3 vs 232 ± 106 µm3, P < 0.001 and 195 ± 86 µm3 vs. 247 ± 106 µm3, P < 0.001, respectively). Lacunar density was also lower in both bone regions of the OVH group (40 ± 18 ×103 lacunae/mm3 vs. 47 ± 9×103 lacunae/mm3 in the lamellar region, P = 0.003 and 63 ± 18×103lacunae/mm3 vs. 75 ± 13×103 lacunae/mm3 in the disorganized region, P < 0.001). Vascular canal volume was lower in the disorganized region of the bone in the OVH group compared to the same region in the control group (P < 0.001). Indentation moduli were not different between the study groups in both bone regions.DiscussionChanges to cortical bone associated with estrogen deficiency in rats require high-resolution methods for detection. Caution is required in the application of these results to humans due to major structural differences between human and rat bone.

【 授权许可】

CC BY