Mei has found that two genes, important for human development and implicated in other disorders including cancer and seizures, normally enable a healthy balance of brain cell excitation and inhibition. In 2007, Mei’s lab showed neuregulin-1 and its receptor, ErbB4, promote ‘inhibition’ at the site of inhibitory synapses in the brain by increasing release of GABA, a major inhibitory neurotransmitter. Seven years earlier, he led a team that showed that the gene pair ‘suppresses’ synapses between neurons where the neurotransmitter glutamate excites cells to action. “According to our model, it inhibits,” Mei says of neuregulin-1.
Schizophrenia has been labeled a degenerative disease where neurons die and a developmental disease where the wiring is laid wrong. Mei’s research shows problems in neuron communication, likely also are to blame. “It’s a complex disease,” says Mei in which neuregulin-1 expression is off balance, possibly the result of mutations in the neuregulin-1 gene.
Neuregulin-1 actually has about six known types, and type I is expressed in higher levels in the pre-frontal cortex of schizophrenics, the portion of the brain critical to cognition, learning and working memory. That 2004 finding by National Institute of Mental Health scientists shifted the focus toward type I and Mei toward development of an animal model that also expresses high levels of type I neuregulin. Most studies, including his, use models in which the genes are knocked out.
“Dr. Mei exemplifies the kind of individual we try to single out for the Distinguished Investigator Award: an outstanding scientist, representing the very best in the field, with an important body of work behind him, and currently pursuing innovative and promising research,” says Geoff Birkett, NARSAD president.
MEDICA.de; Source: Medical College of Georgia