Decrease in Brain Neurotransmitter Linked to Multiple Sclerosis
Multiple sclerosis is an autoimmune disease that is caused by damage to the protective covering that surrounds nerve cells, called myelin. Researchers are not sure what triggers the inflammation that causes the nerve damage, but scientists from the University of Illinois at Chicago have discovered that a decrease in a particular neurotransmitter, called noradrenaline, may be related to increased stress on the neurons.
Damage to Locus Coeruleus May Lead to Decreased Noradrenaline
Noradrenaline, also called norepinephrine, is released naturally by the nerve cells. It is often referred to as the “fight or flight” chemical, as it is responsible for the body’s reaction to stressful situations.
The UIC researchers focused their attention in an area of the brain called the locus coeruleus, located in the brain stem. This region is responsible for mediating many of the sympathetic effects during stress, including the release of noradrenaline. The area has also been studied for its potential role in Alzheimer’s and Parkinson’s diseases, as noradrenaline can act on certain brain receptors to increase working memory.
Douglas Feinstein, a research professor in anesthesiology at the UIC College of Medicine, and colleagues suspect that damage to the locus coeruleus causes a decreased in the production of noradrenaline. Because the neurotransmitter plays an important role as a immunosuppressant in the brain, lack of noradrenaline could lead to inflammation and stress on the neurons.
Noradrenaline is also known to help preserve the integrity of the blood-brain barrier. MS progression may involve the infiltration of white blood cells through this barrier.
"This is the first time that it has been demonstrated that there is stress involved to the neurons in the LC of MS patients, and that there is a reduction in brain noradrenaline levels," said Paul Polak, research specialist in the health sciences in anesthesiology and first author on the paper, published online in the journal Brain.
"There are a number of FDA-approved drugs that have been shown to raise levels of noradrenaline in the brain, and we believe that this type of therapeutic intervention could benefit patients with MS and other neurodegenerative diseases, and should be investigated," he added.
Brand names of norepinephrine reuptake inhibitors, which block the action of the norepinephrine transporter and leads to increased extracellular concentrations of noradrenaline, include Strattera, Vestra, and Vivalan.