ABSTRACT
Sarm1 (sterile α and TIR motif-containing protein-1) is a NADase enzyme that is highly expressed in
the nervous system. The Sarm1 enzyme serves as a metabolic biosensor and is activated in response to
injury, inflammation, and oxidative stress. Based on a screen of thousands of candidates in 2013, Sarm1 was
identified as the central executioner of nerve axon degeneration. Since this time, Sarm1 has also been shown
to modulate nerve function through regulation of MAPK signaling and metabolite turnover. In response to this
pivotal discovery, Sarm1 inhibitors are now being developed for clinical management of neurodegenerative
disease. Specific to bone - nerve damage, dysfunction and clinical neuropathy have all been related to fracture
risk and impaired bone health in diverse conditions including spinal cord injury, anorexia, chemotherapy,
multiple sclerosis and diabetes. However, the molecular mechanisms underlying these relationships remain
unclear, limiting our options for therapeutic intervention. Recently, we discovered that knockout of Sarm1
prevents bone fragility in diabetic mice. Our central hypothesis is that neural Sarm1 activation restricts bone
formation, leading to decreased bone mass and strength. Conversely, we hypothesize that targeted Sarm1
inhibition can be used to simultaneously promote bone and nerve health in states of chronic Sarm1 activation,
such as diabetes. To test this hypothesis, we will pursue two specific aims. First, we will isolate the role of
Sarm1-dependent neuropathy in the progression of skeletal disease. Second, we will target the function of
Sarm1 to restore bone health in vivo. When complete, this work will define the mechanisms linking nerve
damage to impaired bone health through Sarm1. We will also determine if Sarm1 inhibition is a strategy that
can be used to support bone formation in settings of skeletal disease. Our long-term goal is to promote lifelong
health and healthy aging by developing strategies to prevent or to reverse nerve and bone damage across
diverse disease states, beginning in childhood and adolescence and continuing throughout the lifespan.