Phoenix, Arizona is the home of the Barrow Neurological Institute, which is housed at St. Joseph’s Hospital and Medical Center. Barrow researchers have identified new indications of stem cell activity in the brain. This new stem cell activity presents an exciting new window into how brain injuries affect newborn babies and potential target for treating neurological diseases or brain trauma.
The leader of this study is Dr. Nader Sanai, who is the director of Barrow’s Brain Tumor Research Center. Collaborators in this study included researchers from University of California San Francisco and the University of Valencia in Spain. Dr, Sanai’s research group examined human neural stem cells in a region of the brain called the subventricular zone. Brain stem cells reside in a part of the brain called the subventricular zone, a structure that is rather rich in neural stem cells.
According to Dr. Sanai and coworjers, in the first few months of life, young, migrating neurons born in the subventricular zone primarily move to the “prefrontal cortex.”
However, after the first year of life, the subventricular zone of the brain decreases, slowing down substantially after 18 months of life and stopping altogether at 2 years of age. These data settle conflict with prior reports that suggested that human neural stem cell cells remain highly active into adulthood. According the Dr. Sanai: “In the first few months of life, we identified streams of newly generated cells from the subventricular portion of the brain moving toward the frontal cortex. The existence of this new pathway, which has no known counterpart in all other studied vertebrates, raises questions about the mechanics of how the human brain develops and has evolved.”
This study could have important implications for understanding neonatal brain diseases that sometimes cause death or devastating, life-long brain damage. Such conditions include germinal matrix hemorrhages, which are the most common type of brain hemorrhage that occurs in infants; and perinatal hypoxic – ischaemic injuries, exposure to low oxygen and decreased blood flow that can lead to diseases such as cerebral palsy and seizure disorders. Such oxygen deprivation could potentially adversely affect the neural stem cell populations in the neonatal brain and kill them off, prevent them from migrating, or simply turn them off. This would prevent maturation of the brain as the infant grows and subsequent brain immaturity or abnormalities.