Nanomedicine study with rabbits hints at possible breakthrough for cerebral palsy: US researchers
By Kerry Sheridan, AFP
April 20, 2012, 12:28 am TWN
WASHINGTON--A new treatment helped rabbits born with cerebral palsy regain near-normal mobility, offering hope of a potential breakthrough in treating humans with the incurable disorder, researchers said Wednesday.
The method, part of the growing field of nanomedicine, worked by delivering an anti-inflammatory drug directly into the damaged parts of the brain via tiny tree-like molecules known as dendrimers.
Baby rabbits treated within six hours of birth showed "dramatic improvement in motor function" by the fifth day of life, said lead author Sujatha Kannan of the National Institute of Child Health and Human Development Perinatology Research Branch.
The study appears in the journal Science Translational Medicine.
Rabbits who were born immobile due to cerebral palsy were moving around at "almost ... normal healthy levels by day five," said an accompanying article in the same journal by Chicago pediatrician Sidhartha Tan.
The drug was one that is commonly used to treat people who overdose on acetaminophen, known as N-acetyl-L-cystine or NAC, and was given at a 10 times smaller amount.
However, it was successful because the nanodelivery method allowed it to cross the blood-brain barrier and swiftly shut down inflammation in the brain.
Kannan said her team used rabbits because, like humans, their brains develop some before birth and some after birth, whereas most other animals are born with their motor abilities already formed.
"An advantage of that is we can test therapies and look at the improvement in motor function using this kind of animal model," she said.
While experts say it may be many years before it will be known if this approach can be used in human babies, the research shows an important proof of concept that some type of early intervention can reverse brain damage.
"The importance of this work is that it indicates that there is a window in time, immediately after birth, when neuroinflammation can be identified and when treatment with a nanodevice can reverse the features of cerebral palsy," said co-author Roberto Romero, an obstetrician at the National Institute of Child Health and Human Development.
Cerebral palsy affects about 750,000 children and adults in the United States, and its prevalence rate is about 3.3 per 1,000 births, according to Romero.