Growing Brain Cells
Drugs that trigger the birth of neurons could provide the next generation of treatments for neurodegenerative diseases such as Parkinson’s

SOURCE: “Dopamine D₃ Receptor Agonist Delivery to a Model of Parkinson’s Disease Restores the
Nigrostriatal Pathway and Improves Locomotor Behavior”
J. M. Van Kampenand C. B. Eckman
Journal of Neuroscience 26(27): 7272-7280

Results: Scientists at the Mayo Clinic in Jacksonville, FL, found that a drug similar to ones used to treat Parkinson’s disease can spur growth of new neurons in the substantia nigra, the brain area damaged in the disease. In a study of rodents genetically engineered to model Parkinson’s disease, twice as much neurogenesis, or birth of new neurons, was seen in animals treated with the drug as in control animals. Many of the newly generated cells appeared to develop into dopamine-producing neurons–the kind that are lost in Parkinson’s. In addition, treated animals showed an 80 percent improvement in motor ability.

Why it matters: Current treatments for Parkinson’s disease replace or mimic dopamine, an important signaling molecule in the brain. But those treatments lose their effectiveness over time; boosting the brain’s ability to make more of the dopamine-­producing cells could provide a more effective strategy.

Methods: Scientists treated rodents with a compound that triggers a dopamine receptor, delivering it directly to their brains for up to eight weeks. They then tracked the birth and development of new neurons and monitored the rodents’ performance in motor tasks.

Next steps: The team is now testing drugs currently used to treat Parkinson’s disease to see if they also trigger neurogenesis and, if so, how best to deliver these compounds to maximize effectiveness. Ultimately, they hope to find compounds that will help replace cells lost in a range of neurodegenerative diseases, such as Alzheimer’s and Huntington’s.