Drug Therapy May Cut Learning Problems In Down Kids
A U.S. study has raised hopes of developing a drug therapy to reverse the learning problems associated with Down syndrome, according to a published report in the journal of Science Translational Medicine. Down syndrome, a genetic disorder caused by an extra copy of chromosome 21, is associated with deficits in the memory centers, which make it difficult for the brain to store and use experiences in order to form new memories. The study pinpoints the brain deficits and suggests a possible way to tackle them.
During the study, researchers from Stanford University and the Lucile Packard Children’s Hospital worked on mice genetically engineered to mimic Down syndrome. When placed in an unfamiliar cage, the genetically engineered mice failed to start building new nests. The researchers discovered that cells in the hippocampus area of the genetically engineered animals’ brain were starved of noradrenaline, a chemical that helps nerve cells communicate with each other. The lack of noradrenaline seems to be due to the deterioration of the locus coeruleus, an area of the brain, which usually communicates with the hippocampus during the formation of memories, caused by the APP gene contained on the extra chromosome 21. The researchers found that when levels of the chemical were artificially boosted, it had an almost instant positive effect on the animals’ behavior—they started nest building, and improved their performance on other tests as well.
Researchers suspect the best approach for raising chemical levels may be to focus in tandem on noradrenaline and another brain chemical that has been implicated in Down syndrome, acetylcholine. A lead researcher involved with the study, Dr. Ahmad Salehi, said the study suggested that an early intervention with the right drugs might help children with Down syndrome to collect and make sense of information.