Chicago - US researchers have reversed the symptoms of mental retardation and autism in mice by inhibiting an enzyme that affects the connections between brain cells, researchers said on Wednesday.
In a series of experiments on mice, the MIT investigators showed that they could undo the brain damage seen in a condition called Fragile X syndrome by inhibiting a key brain chemical called PAK.
In humans, Fragile X syndrome (FXS) is the leading cause of mental retardation and the most common genetic cause of autism - the complex and devastating developmental disorder that is now being diagnosed in increasing numbers of children.
Continues Below ↓
The study raises the intriguing possibility that the brain damage seen in children with the condition can be rolled back and identifies a specific target for potential drug therapies.
"It opens up a new avenue for drug research to treat this condition," said Susumu Tonegawa, a neuroscientist at the Massachusetts Institute of Technology in Cambridge, Massachusetts, and lead author of the paper.
MIT researchers began by creating a batch of mice that had been genetically modified to have Fragile X, a condition in which the neurons of the brain are structurally abnormal and functionally impaired compared to regular nerve cells.
These transgenic mice had many of the behavioural problems seen in kids with the condition: hyperactivity, attention deficits, repetitive behaviours and poor social skills.
The investigators then cross-bred these mice with another batch of mice that had been genetically modified to inhibit the activity of the PAK (p21-activated kinase) enzyme which is instrumental in shaping the formation of neuronal connections in the brain.
The researchers knew that when PAK was inactivated, the mice developed neurons that had short, fat dendritic spines, with a higher-than-usual capacity for relaying the electrical impulses that pass between brain cells.
Continues...
|
StumbleUpon
Reddit
Digg
Delicious
Newsvine
Facebook
muti
Twitter
