Musculoskeletal System Commons^™

Sexually Dimorphic Effects Of Gpnmb Modulation On Vertebral Bone Mass Regulation And Intravertebral Disc Health, Hakem Altawil, Fayez Safadi

Williams Honors College, Honors Research Projects

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 …

Osteoprogenitor Cells From Non-Regenerative Bone Show Greater Resistance To Cellular Stress Than Those From Regenerative Bone, Joshua Broussard, Sylvia Culpepper, Tyrel Long, Alexander J. Trostle, Robert J. Tower, Mimi C. Sammarco, Jennifer Simkin

School of Medicine Faculty Publications

INTRODUCTION: Bone regeneration following injury depends on osteoprogenitor cells derived predominantly from the periosteum. Incomplete regeneration has been attributed to both cell-extrinsic factors (e.g., environment, inflammation, mechanical instability) and cell-intrinsic factors (e.g., impaired proliferation or differentiation of stem cells). In the digit amputation mouse model, amputation through the third phalanx (P3) supports complete regeneration, while amputation through the second phalanx (P2) results in callus formation and scarring. Periosteal cells are known to be the major contributing cell source for repair and regeneration. Yet the healing outcomes of P2 and P3 amputations are significantly different. This study tests whether P2 and …

Musculoskeletal Changes In Pregnancy: Implications For Long-Term Bone & Joint Health, Jaylyn Thompson, Clarence Julian Clark Ii, Nayarith Lopez, Aziza Ndaw

Rowan-Virtua Research Day

Pregnancy and lactation represent significant physiological challenges to maternal skeletal health, with substantial implications for both short and long-term musculoskeletal integrity. Research emphasizes that lactation induces notable skeletal adaptations, with up to 10% bone mineral density loss occurring in trabecular-rich regions such as the spine and hip (1,5). While most women experience substantial recovery post-weaning, the research indicates that recovery patterns vary significantly, with some women experiencing incomplete restoration of bone mass, potentially compromising long-term skeletal strength (3).

The underlying mechanisms driving these changes are primarily hormonal, with elevated parathyroid hormone-related protein (PTHrP) and decreased estrogen levels during lactation facilitating …

The Development And Evaluation Of A Method For Complete Collagenase I Digestion Of Bos Taurus Bone Samples, Reilly Price

Master of Science in Forensic Science Directed Research Projects

Current methods for processing aged forensic bone samples for DNA analysis involve pulverization and organic extraction, which further destroys already degraded DNA and uses large amounts of limited samples. Additionally, the success rates for this type of analysis vary widely as homogenization incorporates PCR inhibitors into the sample. Little research has explored how pulverization results in DNA damage in profiles obtained from skeletal remains. This study proposes an enzymatic digestion method to separate osteocytes from PCR inhibitors in the extracellular bone matrix to improve the quality and quantity of DNA isolated from aged bone samples. The technique described here used …

The Physiological Interaction Of Sleep Deprivation And Zoledronate On Distal Femur Trabecular Thickness Of Ovariectomized Rats, Erin Nolte, Frank Frisch, Oliver Lopez

Health Sciences and Kinesiology Faculty Articles

Osteoporosis, a disease resulting in an increased risk of fracture due to compromised bone, affects 1 in 3 postmenopausal women. Discontinuities in the microarchitecture of bone, such as trabeculae, are seen in postmenopausal osteoporosis. This study aimed to evaluate how sleep deprivation affects the distal femur trabecular thickness of estrogen-deficient rats treated with Zoledronate. 29 ovariectomized Wistar female rats were separated into 4 groups. The control group (C) was housed in standard housing with a 12-hour light/dark cycle and was given an intravenous injection of 0.45 mL of 0.9% saline. The Zoledronate group (Z) were also housed in standard conditions …

Evaluating Sex Related Differences In The Osteocyte Lacunar Canalicular Network Across The Lifespan: A Confocal Laser Scanning Microscopy Approach, Gina Tubo

Williams Honors College, Honors Research Projects

Bone is a dynamic tissue with the ability to remodel itself. This capability is facilitated via communication mechanisms through the osteocyte-lacunar-canalicular (LCN) network. Osteocytes are bone cells housed in small, hollow spaces called lacunae. Lacunae are linked by canals called canaliculi. A diminished network can lead to the inability to form bone following breakdown. A decrease in osteocyte-LCN density has been shown to correlate with aging (Ashique et al. 2017). This decline leads to the development of osteoporosis. Osteoporosis preferentially affects women. Prior studies have shown that women older than 50 are four times more likely to be osteoporotic when …

Activin Receptor Type 2a (Acvr2a) Functions Directly In Osteoblasts As A Negative Regulator Of Bone Mass, Brian C. Goh, Vandana Singhal, Angelica J. Herrera, Ryan E. Tomlinson, Soohyun Kim, Marie-Claude Faugere, Emily L. Germain-Lee, Thomas L. Clemens, Se-Jin Lee, Douglas J. Digirolamo

Internal Medicine Faculty Publications

Bone and skeletal muscle mass are highly correlated in mammals, suggesting the existence of common anabolic signaling networks that coordinate the development of these two anatomically adjacent tissues. The activin signaling pathway is an attractive candidate to fulfill such a role. Here, we generated mice with conditional deletion of activin receptor (ACVR) type 2A, ACVR2B, or both, in osteoblasts, to determine the contribution of activin receptor signaling in regulating bone mass. Immunohistochemistry localized ACVR2A and ACVR2B to osteoblasts and osteocytes. Primary osteoblasts expressed activin signaling components, including ACVR2A, ACVR2B, and ACVR1B (ALK4) and demonstrated increased levels of phosphorylated Smad2/3 upon …

The Role Of Osteocyte Estrogen Receptor Beta (Erβ) In Regulating The Skeletal Response To Mechanical Loading, Julia P. Townsend, Russell P. Main

The Summer Undergraduate Research Fellowship (SURF) Symposium

Estrogen’s biological functions are mediated by estrogen binding to estrogen receptors (ER). Understanding what role both ERα and ERβ have in bone maintenance and formation can contribute to possible treatment of osteoporosis. This study examined osteocyte specific deletion of ERβ in mice. The cross of ERβ-floxed mice with DMP1-8kb-Cre mice provided both experimental knockout mice as well as littermate control mice. At 24 weeks of age the left tibiae of all mice were mechanically loaded five days per week for two weeks to induce bone formation. Analysis of cortical bone was conducted using microcomputed tomography (microCT) to measure load-induced changes …

Segmental Musculoskeletal Examinations Using Dual-Energy X-Ray Absorptiometry (Dxa): Positioning And Analysis Considerations, Nicolas H. Hart, Sophia Nimphius, Tania Spiteri, Jodie L. Cochrane, Robert U. Newton

Research outputs 2014 to 2021

Musculoskeletal examinations provide informative and valuable quantitative insight into muscle and bone health. DXA is one mainstream tool used to accurately and reliably determine body composition components and bone mass characteristics in-vivo. Presently, whole body scan models separate the body into axial and appendicular regions, however there is a need for localised appendicular segmentation models to further examine regions of interest within the upper and lower extremities. Similarly, in-consistencies pertaining to patient positioning exist in the litera-ture which influence measurement precision and analysis out-comes highlighting a need for standardised procedure. This paper provides standardised and reproducible: 1) positioning and analysis …

Nanosized Hydroxyapatite And Other Calcium Phosphates: Chemistry Of Formation And Application As Drug And Gene Delivery Agents, Vuk Uskoković, Dragan Uskoković

Pharmacy Faculty Articles and Research

The first part of this review looks at the fundamental properties of hydroxyapatite (HAP), the basic mineral constituent of mammalian hard tissues, including the physicochemical features that govern its formation by precipitation. A special emphasis is placed on the analysis of qualities of different methods of synthesis and of the phase transformations intrinsic to the formation of HAP following precipitation from aqueous solutions. This serves as an introduction to the second part and the main subject of this review, which relates to the discourse regarding the prospects of fabrication of ultrafine, nanosized particles based on calcium phosphate carriers with various …