Stroke, the third leading cause of death in adults in the United States, occurs when blood flow to the brain is interrupted. Deprived of oxygen, brain cells die within minutes, causing inflammation and further damage to tissue surrounding the site where blood flow is obstructed.
In the study, a research team led by Byron Ford, PhD, of the MSM Neuroscience Institute and Department of Anatomy and Neurobiology and CBN, examined the effects of administering neuregulin-1 to rats after surgically induced strokes. The scientists discovered the compound reduced cell death by 90 percent compared to rats that did not receive it. Neuregulin-1 also protected neurons from damage even when administered as long as 13 hours after the stroke's onset.
In DNA microarray analysis of the affected brain tissue, Ford and his team determined neuregulin-1 produces its protective effects by turning on or off nearly 1,000 genes that regulate cell death and inflammation. Neuregulin-1 also blocks the production of free radicals, compounds that have been implicated in cell injury and aging.
Currently, a drug called TPA is the only available stroke treatment, and must be administered within three hours of stroke onset to be effective. "The biggest potential benefit of neuregulin-1 is that its therapeutic window is much longer than TPA, potentially up to 48 hours," said Ford. "It also appears to easily cross the blood-brain barrier and does not produce any obvious side effects in rats."
Ford has filed two provisional patents for the uses of neuregulin-1 as a stroke treatment and promoting the growth of endogenous neural stem cells to replace damaged neurons.
Ford was recently awarded a five-year R01 grant from the National Institute of Neurological Disorders to begin pre-clinical studies of neuregulin-1 as a stroke therapy. As part of this project, Ford will test neuregulin-1 in additional animal models and conduct imaging studies to determine the optimal therapeutic window for the compound to be protective. He also intends to better characterize the molecular processes involved in the stroke process to facilitate the development of novel therapies for stroke.
In collaboration with CBN colleague Kerry Ressler, MD, PhD, an Emory University researcher, Ford also is studying the function of neuregulin-1 in the brain's fear mechanisms and its possible connection with schizophrenia. Schizophrenia, which is characterized by a dysfunction of the brain's fear mechanisms, has been linked to a mutation in the neuregulin-1 gene. Other studies have found that schizophrenics have lower than normal brain levels of neuregulin-1.
Co-authors of Ford's latest stroke study include graduate student DaJoie Croslan, postdoctoral fellow Adalynn Harris, PhD, and research assistant Gregory Ford, all of the MSM Department of Anatomy and Neurobiology, and Zhenfeng Xu, MD/PhD, a postdoctoral fellow at Johns Hopkins University.
Founded in 1975, the Morehouse School of Medicine (MSM) provides medical education to those who seek to increase access to health care and to eliminate health disparities among the nation's underserved individuals and communities. MSM is separate from Morehouse College.
The Neuroscience Institute at MSM was the first institute devoted to the study of the nervous system and its disorders at a Historically Black College or University. Its success gave rise to the NIH-funded Specialized Neuroscience Research Programs located at minority-serving institutions across the nation.
CBN, a National Science Foundation Science and Technology Center, is a research and education consortium of eight metro Atlanta colleges and universities. More than 90 neuroscientists lead the interdisciplinary research program to understand the neurobiology of complex social behaviors. CBN studies have led to a breakthrough treatment for anxiety-related disorders and new understanding of the neurochemicals vasopressin and oxytocin in social behavior. In addition to research, CBN has a comprehensive education program designed to improve science literacy and attract more women and underrepresented minorities to neuroscience programs. The center is supported by more than $53 million in grants from NSF and the Georgia Research Alliance.