Your Brain and Protein Power

As nerve cells develop, they grow connections and become integrated into neural networks that transmit electrochemical signals through the nervous system. Once these networks are established, a neuron’s capacity for growth and formation of new connections is diminished. This loss of neural plasticity is why an ageing or damaged brain is unable to repair itself by forming new connections.

But UBC researchers have discovered that neurons don’t lose their capacity for growth; rather, they are prevented from doing so. Researchers have pinpointed the agents involved in neural growth and suppression: the proteins calpain and cortactin. Cortactin activates neural growth, and calpain blocks cortactin once the neuron has developed and integrated into the nervous system.

The researchers were able to demonstrate in animal models that suppression of calpain results in greater neural plasticity. They are hopeful their discovery will lead to new treatments for neurological disorders and boost in the efficacy of treatments for other conditions.

Ana Mingorance-Le Meur, a postdoc in the department of Cellular and Physiological Sciences, is study lead along with professor Timothy O’Connor. “The maintenance of neuronal connections is an active process that requires constant repression of the formation of nerve sprouts by the protein calpain to avoid uncontrolled growth,” she says. “But a consequence of this role is that calpain limits
neural plasticity and the brain’s ability to repair itself. The next step is to find a way to enhance neural plasticity without interfering with the good connections that are already in place.” Mingorance-Le Meur is also a member of the Brain Research Centre at UBC and VCH Research Institute.

UBC Alumni’s Trek magazine Issue 23, Spring 2009 p 7