A team of scientists have discovered that selenium, a micronutrient, can help boost the antioxidant system on the heels of stroke in animals and suggests that a similar treatment could be used to limit brain damage in patients. Stroke is a leading cause of disability and death in the United States, occurring once every 40 seconds. Few treatments are available to limit brain damage after a stroke. Researchers at the Burke Neurological Institute (BNI) in White Plains, an academic affiliate of Weill Cornell Medicine, have delivered selenium directly to the brain in doses that exceed nutritional requirements in order to build resilience to the effects of stroke by turning on the body’s natural defenses. Animals that received selenium had much less neuronal damage, and were functionally much healthier than their littermates not exposed to the micronutrient. Selenium is an essential nutrient found in Brazil nuts, eggs, fish, chicken and brown rice.
The findings will be published in the May 16th issue of Cell and provide the first example of how a nutrient can be embedded in a drug to drive a broad program of cellular defenses that can tackle the many facets of stroke-induced injury.
“We were amazed to find that delivery of selenium to the brain in the absence of selenium deficiency could flip a switch to turn on the body’s defense mechanisms in combatting both ischemic or hemorrhagic stroke,” said Rajiv Ratan M.D., Ph.D., Director of the Burke Neurological Institute and senior author on the study. “We developed a peptide that allows us to turn on these defense mechanisms in any organ of the body, including the brain, providing hope not only for treatment of neurological conditions but also those afflicting other organs like the kidney or the liver. We worked as a team with collaborators from around the country to develop this exciting approach.”
This study explains how the specifically engineered selenium peptide (SelPep), which Dr. Ratan’s laboratory developed, creates a wide therapeutic window to deliver selenium to the entire body safely. A cassette of genes called the “selenome” are activated and protect and repair the brain.
An estimated one billion people worldwide are selenium-deficient, suggesting the strategy might also be used to normalize selenium in those individuals. There are at least 25 known proteins (selenoproteins) that assist the brain with motor function, coordination, memory, and cognition. Remarkably, systematic (whole body) administration of this peptide inhibits nerve cell death and improves function when delivered in hemorrhagic or ischemic stroke models. The knowledge of how this adaptive system works will provide a better understanding of how this nutrient works to protect the brain and offers hope for patients who have neurological impairments caused by stroke, Parkinson’s disease, ALS and other neurological diseases.