2-Minute Neuroscience: Multiple Sclerosis

Описание: Multiple sclerosis is a central nervous system disorder that can create a variety of symptoms ranging from visual disturbances to paralysis. It is characterized by damage to myelin, the insulatory material that surrounds neurons. This damage is linked to disruptions in healthy neuronal function, which are thought to lead to the symptoms of the disease. Most researchers believe the myelin damage that occurs in multiple sclerosis is due to the cells of the immune system targeting myelin. Thus, most of the treatments for multiple sclerosis involve drugs that suppress the immune response in some way.

The MRI image in this video is courtesy of VoiceOfReason at English Wikipedia and can be seen here: https://upload.wikimedia.org/wikipedi...

TRANSCRIPT:

Welcome to 2 minute neuroscience, where I simplistically explain neuroscience topics in 2 minutes or less. In this installment I will discuss multiple sclerosis.

Multiple sclerosis, or MS, is a central nervous system disorder that involves the abrupt appearance of neurological symptoms, which usually occur for the first time between the ages of 20 and 50. The symptoms of MS vary from person to person, and almost any nervous system function can be disrupted in the disease. The most common initial symptoms involve visual disturbances, abnormal sensations, and weakness. The causes of the disease are not fully understood and are thought to involve genetic and environmental factors.

Multiple sclerosis is characterized by damage to the myelin sheaths surrounding the axons of neurons in the central nervous system. This myelin damage disrupts the conduction of action potentials along these axons, which is thought to cause many of the symptoms of the disease. The myelin damage can also lead to the deterioration of axons. The brains of MS patients can contain evidence of this damage in the form of plaques or lesions that are visible with some types of neuroimaging.

The reason these attacks on a patient’s myelin occur is not fully understood, but the damage in MS is most commonly attributed to an autoimmune attack. According to this hypothesis, the immune system in a patient with MS targets myelin, treating it as foreign. This autoimmune attack and the associated inflammatory response leads to damage to myelin, axons, and glial cells. What prompts the autoimmune attack is not known, however, and some have argued that MS is caused by a persistent infection instead.

Either way, MS seems to involve excessive immune system activation in some respect, and the drugs that have proven most successful in treating it act to reduce inflammatory or other immune responses.

REFERENCE:

Purves D, Augustine GJ, Fitzpatrick D, Hall WC, Lamantia AS, McNamara JO, White LE. Neuroscience. 4th ed. Sunderland, MA. Sinauer Associates; 2008.