Brain Cell Growth Is Spurred by Protein Absent in Brains of Mice

A protein that may partly explain why human brains are larger than those of other animals has been identified by scientists from two stem-cell labs at UC San Francisco, in research published in the November 13, 2014 issue of Nature.

Key experiments by the UCSF researchers revealed that the protein, called PDGFD, is made in growing brains of humans, but not in mice, and appears necessary for normal proliferation of human brain stem cells growing in a lab dish.

Researchers recently found that an immune-system protein called MHCI, or major histocompatibility complex class I, moonlights in the nervous system to help regulate the number of synapses, which transmit chemical and electrical signals between neurons.

When it comes to the brain, "more is better" seems like an obvious assumption. But in the case of synapses, which are the connections between brain cells, too many or too few can both disrupt brain function.

“With this information we hope to better understand the earliest stages in the development of this disease and gain information to guide prevention and treatment efforts.” -Sigan Hartley

The link between a protein typically associated with Alzheimer's disease and its impact on memory and cognition may not be as clear as once thought, according to a new study from the University of Wisconsin-Madison's Waisman Center. The findings are revealing more information about the earliest stages of the neurodegenerative disease.

A new study provides the most definitive characterization of the autism-like intellectual disability disorder Christianson syndrome and provides the first diagnostic criteria to help doctors and families identify and understand the condition. Initial evidence suggests CS could affect tens of thousands of boys worldwide.

Because the severe autism-like condition Christianson syndrome was first reported only in 1999 and some symptoms take more than a decade to appear, families and doctors urgently need fundamental information about it. A new study that doubles the number of cases now documented in the scientific literature provides the most definitive characterization of CS to date. The authors of the study propose the first diagnostic criteria for the condition. “We’re hoping that clinicians will use these criteria and that there will be more awareness among clinicians and the community about Christianson syndrome,” said Dr. Eric Morrow, assistant professor of biology and psychiatry and human behavior at Brown University and senior author of the study in press in Annals of Neurology. “We’re also hoping this study will impart an opportunity for families to predict what to expect for their child and what’s a part of the syndrome.”

New research also suggests common antibiotic might help treat the genetic defect

Researchers from UC Davis School of Medicine and Shriners Hospitals for Children – Northern California have identified a group of cells in the brain that they say plays an important role in the abnormal neuron development in Down syndrome. After developing a new model for studying the syndrome using patient-derived stem cells, the scientists also found that applying an inexpensive antibiotic to the cells appears to correct many abnormalities in the interaction between the cells and developing neurons. “We have developed a human cellular model for studying brain development in Down syndrome that allows us to carry out detailed physiological studies and screen possible new therapies,” said Wenbin Deng, associate professor of biochemistry and molecular medicine and principal investigator of the study. “This model is more realistic than traditional animal models because it is derived from a patient’s own cells.”