A new study has proven promising for treating Down syndrome patients, based on positive reactions to treatment in mice that had memory deficits. The process of increasing levels of the neurotransmitter norepinephrine seemed to improve the thinking ability in mice, which could point to new treatments for Down syndrome patients.
The new study conducted by Dr. Ahmad Salehi of the Veterans Affairs Palo Alto Health Care System, was published in the journal Science Translational Medicine recently. During the study, researchers noticed the mice with Down syndrome-like actions, carried lower levels of norepinephrine in their brains and specifically in their locus coeruleus, than the mice exuding normal actions.
For the study, researchers infected mice with a condition similar to that of Down syndrome in humans and then treated them with drugs to raise the levels of neurotransmitter norepinephrine, which is currently in clinical trials to treat a chronic condition known as fibromyalgia in humans. During the study, when the mice brain levels of norepinephrine dropped, they failed to perform normal behaviors.
The engineered mice did not build nests when they were placed in an unfamiliar cage, something that mice normally do. When the mice were given drugs that boosted their levels of norepinephrine, within a few hours they began to build nests. However, the behavior did not last long before the mice regressed back to their Down syndrome-like behavior.
One in every 733 babies is born with Down syndrome in the United States. The disorder is the leading cause of retardation in children and occurs when an individual’s DNA consists of three rather than two of chromosome 21. The genetically engineered Down syndrome mice used in the study had and extra chromosome 16, but the mice exuded the same characteristics as humans with Down syndrome.