Long thought of as mere bystanders, astrocytes are crucial for the survival and well-being of motor neurons, which control voluntary muscle movements. In fact, defective astrocytes can lay waste to motor neurons and are the main suspects in the muscle-wasting disease amyotrophic lateral sclerosis (ALS).

Scientists report a dramatic success in what may be the first documented rescue of a congenital brain disorder by transplantation of human neural stem cells. The research, published by Cell Press in the June issue of the journal Cell Stem Cell, may lead the way to new strategies for treating certain hereditary and perinatal neurological disorders.

Most cells in the human brain are not nerve cells, but supporting cells (glial cells). They serve as a framework for nerve cells and play an important role in the wound reaction that occurs with injuries to the brain.

When human umbilical cord blood cells (UCBC) were injected into aged laboratory animals, researchers at the University of South Florida (USF) found improvements in the microenvironment of the hippocampus region of the animals’ brains and a subsequent rejuvenation of neural stem/progenitor cells.

Boosted by physical and mental exercise, neural stem cells continue to sprout new neurons throughout life, but the exact function of these newcomers has been the topic of much debate. Removing a genetic master switch that maintains neural stem cells in their proliferative state finally gave researchers at the Salk Institute for Biological Studies some definitive answers.