Acute Administration of Intranasal Insulin to Improve Outcome After Spinal Cord Injury

Over 12,000 new spinal cord injuries (SCI) occur every year in the United States alone, leading to permanent functional problems. While young adults have the highest risk of SCI, the average age of injury is steadily increasing as our population ages, and the average age of a SCI is now 45 years old. Our data indicates that the injury response differs in young adult and middle-aged rodent SCI models, suggesting that different therapies (doses, administration times, targets) may be needed for the different populations. However, there are no therapies that alleviate post-injury motor impairments or address the differences in aging populations. We and others have found that insulin delivered via an intranasal route is able to reach the spinal cord via the cerebrospinal fluid and can improve outcomes after injury, similar to improvements seen after brain injury or in Alzheimer's disease. Intranasal insulin can directly penetrate central nervous system tissue without altering in blood glucose or blood insulin levels. Our objective is to therefore determine the optimal dose and treatment regimen to improve motor recovery after spinal cord injury in young adult and middle-aged populations. Ultimately, this proposal will provide an acute therapeutic for spinal cord injured patients by improving neuron survivability and reducing inflammation. Because intranasal insulin administration has already been deemed safe for use in humans by the FDA and is currently in clinical trials for treatment of Alzheimer's dDisease, the translation of this therapy for SCI will be relatively rapid. This therapy will therefore offer our service members an opportunity to improve their quality of life.