The longitudinal effects of ovariectomy on the morphometric, densitometric and mechanical properties in the murine tibia: A comparison between two mouse strains

A thorough assessment of any prospective animal model of human disease is necessary before the substantial investment of resources into a preclinical study of potential therapies. Oestrogen-deficiency and related bone loss following ovariectomy is a common animal model of osteoporosis. In this study we quantified the effects of ovariectomy on the tibia bone morphometric, densitometric and mechanical properties in two common mouse strain, C57BL/6 and BALB/c, using in vivo microCT and micro-finite element analysis to 10 weeks following surgery. Results show persistent trabecular bone loss and inhibition of cortical bone thickening in C57BL/6 mice that was not apparent or otherwise transient in BALB/c. This difference in the bony response to ovariectomy between the mouse strains suggest that BALB/c may be most useful in short-term and C57BL/6 most useful in long term investigations of anti-osteoporotic therapies. This research helped to inform the selection of C57BL/6 in a MULTISIM study on the combined effects of anabolic treatments, PTH(1-34) and mechanical loading, for low bone mass that is currently ongoing within our laboratory.

Left: Mean percentage change, from 14 weeks baseline, in trabecular bone volume fraction (BV/TV) in ovariectomized C57BL/6 (BL6-OVX) and BALB/c (BaC-OVX) compared with non-operated control groups (CTRL).
Right: 3D microCT images of tibia metaphyseal trabecular bone at 14 and 24 weeks.

Roberts, .B C., Giorgi, M., Oliviero, S., Wang, N., Boudiffa, M., Dall’Ara, E. (2019), “The longitudinal effects of ovariectomy on the morphometric, densitometric and mechanical properties in the murine tibia: a comparison between two mouse strains”, Bone, 127, pp 260-270.

URL: https://doi.org/10.1016/j.bone.2019.06.024