Cervical vertebrae for early bone loss evaluation in osteoporosis mouse models

Area of Science:

• Osteoporosis research
• Animal models for skeletal diseases
• Bone biology and biomechanics

Background:

• Osteoporosis (OP) is a prevalent skeletal disease in aging populations, necessitating effective animal models for study.
• Traditional ovariectomy (OVX) or orchiectomy (ORX) models often use lumbar vertebrae, which are not primary weight-bearing in quadrupeds.
• Cervical vertebrae, bearing higher stress in quadrupedal animals, may offer a more sensitive assessment for OP.

Purpose of the Study:

• To compare the utility of murine cervical vertebrae versus lumbar vertebrae for assessing osteoporosis progression.
• To evaluate early-stage bone changes in response to gonadectomy in mice.
• To determine if cervical vertebrae provide a more sensitive model for osteoporosis research.

Main Methods:

• Establishment of ovariectomy (OVX) and orchiectomy (ORX) mouse models.
• Assessment of serum hormone levels and bone biomarkers.
• Micro computed tomography (micro-CT) for bone quantity and quality analysis.
• Histomorphological analysis and micro-indentation for mechanical property evaluation.

Main Results:

• Gonadectomy successfully induced osteoporosis, evidenced by reduced hormone levels and increased bone resorption markers.
• Early-stage (one month post-gonadectomy) bone mineral density (BMD) reduction was significantly greater in cervical vertebrae (16.1-21.7%) compared to lumbar vertebrae (5-7.4%).
• At six months, cervical vertebrae consistently showed greater BMD loss and inferior biomechanical properties (Vickers hardness, elastic modulus) than lumbar vertebrae in OVX and ORX mice.

Conclusions:

• The mouse cervical spine serves as a more sensitive indicator for early-stage osteoporosis evaluation compared to lumbar vertebrae.
• This study introduces a novel mouse model utilizing cervical vertebrae for enhanced assessment of bone remodeling in osteoporosis.
• Cervical vertebrae are recommended for more accurate and earlier detection of OP-related bone changes in animal studies.