Gurjit Mandair, Ph.D.

Staff Scientist

gmandair@umich.edu

Age-related Changes to Human Bone Properties

Age-related decline in bone strength increases the risk of fragility fractures. However, it is unclear if the decline in bone mechanical properties with age is caused by regional variations in bone mass, porosity, or composition. In collaboration with the Jepsen Lab (University of Michigan), we use a fiber-optic Raman probe to study changes in mineral and matrix properties of human bone tissues.  We also characterize the collagen cross-link profile in digested bone by HPLC with fluorescence detection. Furthermore, we examine how these compositional traits are related to bone mechanics and height-adjusted bone robustness measurements.

Lab Member(s): Gurjit Mandair, Morgan Bolger, Genevieve Romanowicz, Jepsen Lab

Role of AGEs in Bone with Age and Diabetes

Advanced glycation end products (AGEs) increase with age in bone, but is exacerbated in patients with diabetes. The role of AGEs on the material properties of diabetic bone and fragility fractures have yet to be clarified. We use in vitro glycation and diabetic rodent models to form AGEs in bone and then quantify the major AGEs formed by using HPLC. We also use Raman spectroscopy to understand how specific AGEs formed in vitro or in vivo perturb the secondary structure of bone collagen.

Lab Member(s): Gurjit Mandair, Genevive Romanowicz, Morgan Bolger

Radiotherapy-induced Changes to Bone Composition

Cancer patients receiving radiotherapy for soft tissue sarcomas are often at risk of post-irradiation (post-RTx) bone fragility fractures, but our understanding of the mechanisms of irradiation bone injury is rudimentary. In collaboration with the Damon Lab (UPSTATE Medical University, New York), a pre-clinical mouse model of limited field hindlimb irradiation is used to evaluate spatial and progressive changes to irradiated tibias. We use Raman microscopy to evaluate spatial and progressive post-RTx changes to cortical bone composition.

Lab Member(s): Gurjit Mandair