Pregnancy and age differentially affect stiffness, injury susceptibility, and composition of murine uterosacral ligaments.

Pelvic organ prolapse is a debilitating condition that diminishes quality of life, and it has been linked to pregnancy and aging. Injury of the uterosacral ligaments (USLs), which provide apical support to the pelvic organs, is a major cause of uterine prolapse. In this study, we examined the effect of pregnancy and age on the apparent elastic modulus, susceptibility to collagen damage, and extracellular matrix (ECM) composition of the murine USL.

Altered post-fracture systemic bone loss in a mouse model of osteocyte dysfunction.

Femur fracture leads to loss of bone at uninjured skeletal sites, which may increase risk of subsequent fracture. Osteocytes, the most abundant bone cells, can directly resorb bone matrix and regulate osteoclast and osteoblast activity, but their role in systemic bone loss after fracture remains poorly understood. In this study we used a transgenic (TG+) mouse model that overexpresses human B-cell lymphoma 2 (BCL-2) in osteoblasts and osteocytes.

Controlled Mechanical Property Gradients Within a Digital Light Processing Printed Hydrogel-Composite Osteochondral Scaffold.

Tissue engineered scaffolds are needed to support physiological loads and emulate the micrometer-scale strain gradients within tissues that guide cell mechanobiological responses. We designed and fabricated micro-truss structures to possess spatially varying geometry and controlled stiffness gradients. Using a custom projection microstereolithography (μSLA) system, using digital light projection (DLP), and photopolymerizable poly(ethylene glycol) diacrylate (PEGDA) hydrogel monomers, three designs with feature sizes < 200 μm were formed: (1) uniform structure with 1 MPa structural modulus ( ) designed to match equilibrium modulus of healthy articular cartilage, (2)  = 1 MPa gradient structure designed to vary strain with depth, and (3) osteochondral bilayer with distinct cartilage (  = 1 MPa) and bone (  = 7 MPa) layers.

Multi-scale cortical bone traits vary in females and males from two mouse models of genetic diversity.

Understanding the genetic basis of cortical bone traits can allow for the discovery of novel genes or biological pathways regulating bone health. Mice are the most widely used mammalian model for skeletal biology and allow for the quantification of traits that cannot easily be evaluated in humans, such as osteocyte lacunar morphology. The goal of our study was to investigate the effect of genetic diversity on multi-scale cortical bone traits of 3 long bones in skeletally-mature mice.