College
Buchtel College of Arts and Sciences
Date of Last Revision
2026-05-07 06:09:21
Major
Biomedical Science
Honors Course
BIOL 499
Number of Credits
4
Degree Name
Bachelor of Science
Date of Expected Graduation
Spring 2026
Abstract
Osteoporosis and vertebral degeneration are major contributors to musculoskeletal morbidity, yet the molecular mechanisms regulating vertebral bone and intervertebral disc (IVD) homeostasis remain incompletely understood. GPNMB (osteoactivin) has been identified as a regulator of bone remodeling, though its role in spine health is unclear. This study evaluated the effects of GPNMB deficiency on lumbar vertebral bone microarchitecture and IVD integrity in a sex-dependent context.
Six-month-old male and female wild-type (WT) and GPNMB knockout (KO) mice were analyzed using micro–computed tomography (µCT) of lumbar vertebrae (L4–L6) and histological assessment of the L5–L6 IVD. KO males exhibited increased bone volume fraction, bone surface density, and trabecular number, alongside decreased trabecular thickness and separation, indicating a shift toward a more numerous but thinner trabecular network. KO females showed a milder phenotype, with increased bone surface-to-volume ratio and reduced trabecular thickness. Cortical bone deficits were most pronounced in KO males, while females exhibited greater cortical bone volume overall. Histological analysis revealed increased IVD degeneration in KO males compared to WT males, with no differences observed in females.
These findings suggest that GPNMB plays a critical, sex-dependent role in vertebral bone and disc homeostasis.
Research Sponsor
Brian Bagatto
First Reader
Fayez F. Safadi
Second Reader
Michael DiSabato
Honors Faculty Advisor
Brian Bagatto
Proprietary and/or Confidential Information
No
Community Engaged Scholarship
Yes
Recommended Citation
Altawil, Hakem and Safadi, Fayez, "Sexually dimorphic effects of GPNMB modulation on vertebral bone mass regulation and intravertebral disc health" (2026). Williams Honors College, Honors Research Projects. 2195.
https://ideaexchange.uakron.edu/honors_research_projects/2195
Included in
Amino Acids, Peptides, and Proteins Commons, Biological Phenomena, Cell Phenomena, and Immunity Commons, Cells Commons, Disease Modeling Commons, Genetic Phenomena Commons, Medical Cell Biology Commons, Medical Molecular Biology Commons, Musculoskeletal Diseases Commons, Musculoskeletal System Commons, Orthopedics Commons, Physiological Processes Commons, Rheumatology Commons