Sex-specific compromised bone healing in female rats might be associated with a decrease in mesenchymal stem cell quantity

Strube, Patrick, Mehta, Manav, Baerenwaldt, Anne, Trippens, Jessica, Wilson, Cameron J., Ode, Andrea, Perka, Carsten, Duda, Georg N., & Kasper, Grit (2009) Sex-specific compromised bone healing in female rats might be associated with a decrease in mesenchymal stem cell quantity. Bone, 45(6), pp. 1065-1072.

View at publisher

Abstract

Introduction

The clinically known importance of patient sex as a major risk factor for compromised bone healing is poorly reflected in animal models. Consequently, the underlying cellular mechanisms remain elusive. Because mesenchymal stem cells (MSCs) are postulated to regulate tissue regeneration and give rise to essential differentiated cell types, they may contribute to sex-specific differences in bone healing outcomes.

Methods

We investigated sex-specific variations in bone healing and associated differences in MSC populations. A 1.5 mm osteotomy gap in the femora of 8 male and 8 female 12-month-old Sprague-Dawley rats was stabilized by an external fixator. Healing was analyzed in terms of biomechanical testing, bridging and callus size over time (radiography at 2, 4, and 6 weeks after surgery), and callus volume and geometry by μCT at final follow-up. MSCs were obtained from bone marrow samples of an age-matched group of 12 animals (6 per gender) and analyzed for numbers of colony-forming units (CFUs) and their capacity to differentiate and proliferate. The proportion of senescent cells was determined by β-galactosidase staining.

Results

Sex-specific differences were indicated by a compromised mechanical competence of the callus in females compared with males (maximum torque at failure, p = 0.028). Throughout the follow-up, the cross-sectional area of callus relative to bone was reduced in females (p ≤ 0.01), and the bridging of callus was delayed (p 2weeks = 0.041). μCT revealed a reduced callus size (p = 0.003), mineralization (p = 0.003) and polar moment of inertia (p = 0.003) in female animals. The female bone marrow contained significantly fewer MSCs, represented by low CFU numbers in both femora and tibiae (p femur = 0.017, p tibia = 0.010). Functional characteristics of male and female MSCs were similar.

Conclusion

Biomechanically compromised and radiographically delayed bone formation were distinctive in female rats. These differences were concomitant with a reduced number of MSCs, which may be causative for the suboptimal bone healing.

Impact and interest:

23 citations in Scopus
Search Google Scholar™
21 citations in Web of Science®

Citation counts are sourced monthly from Scopus and Web of Science® citation databases.

These databases contain citations from different subsets of available publications and different time periods and thus the citation count from each is usually different. Some works are not in either database and no count is displayed. Scopus includes citations from articles published in 1996 onwards, and Web of Science® generally from 1980 onwards.

Citations counts from the Google Scholar™ indexing service can be viewed at the linked Google Scholar™ search.

ID Code: 67013
Item Type: Journal Article
Refereed: Yes
Additional Information: cited By (since 1996)15
Keywords: Bone defect, Bone healing, Gender, MSCs, Sex
DOI: 10.1016/j.bone.2009.08.005
ISSN: 8756-3282
Subjects: Australian and New Zealand Standard Research Classification > BIOLOGICAL SCIENCES (060000) > BIOCHEMISTRY AND CELL BIOLOGY (060100) > Cell Development Proliferation and Death (060103)
Australian and New Zealand Standard Research Classification > BIOLOGICAL SCIENCES (060000) > PHYSIOLOGY (060600) > Animal Physiology - Cell (060602)
Australian and New Zealand Standard Research Classification > MEDICAL AND HEALTH SCIENCES (110000) > CLINICAL SCIENCES (110300) > Orthopaedics (110314)
Divisions: Current > Schools > School of Chemistry, Physics & Mechanical Engineering
Current > Institutes > Institute of Health and Biomedical Innovation
Current > QUT Faculties and Divisions > Science & Engineering Faculty
Copyright Owner: Copyright 2009 Elsevier Inc.
Deposited On: 10 Feb 2014 23:27
Last Modified: 28 Sep 2015 00:00

Export: EndNote | Dublin Core | BibTeX

Repository Staff Only: item control page