Sunday, January 3, 2010

Causes Of Multiple Sclerosis

Up to now, multiple sclerosis is still idiopathic. This means that, although research for its cause is currently and continuously being done, its definite cause still has not been discovered. However, a variety of probable causes has been found. It is through these probable causes that the medical diagnosis of multiple sclerosis can be established.

For starters, there is always the hereditary factor. The hereditary factor is present in almost all of the diseases. For instance, if a great great grandmother had multiple sclerosis, then there is a big chance that her descendants might have the disease as well.

Aside from heredity, the environment, according to researchers, also affects the pathogenesis of multiple sclerosis. An antigen or allergen commonly found in the environment could trigger a response from the body that later on leads to an immunocompromised system.

Multiple Sclerosis being an autoimmune disease

Research has it that multiple sclerosis is an autoimmune disease which means that the body’s personal immune system attacks its own cells. For reasons that are still unknown, the body’s immune cells show aggression towards and obliterate the myelin sheath that covers the neurons like an insulator inside the brain and the spinal cord.

This myelin sheath is responsible for the transmission and the prevention of unnecessary electrical activity that short circuits one cell from another cell. Once communication between the brain and the other parts of the body is disrupted, the transmission of sensations and control messages are not anymore normal. This pathophysiology is that of multiple sclerosis.

Plaques in multiple sclerosis

The progression of the disease’s symptoms is correlated with the development of new plaques within the parts of the brain that simultaneously control the affected areas. These plaques are developed from the demyelinated areas, which are basically the tiny round areas of gray neuron that no longer has a white myelin covering.

What makes multiple sclerosis more complicated is that, the pattern of the appearance of the plaques has absolutely no pattern. This makes multiple sclerosis completely unpredictable.

Inflammation of the myelin sheath

Normal cells are covered by a sheath that acts as an insulator. This sheath is made up of adipose substances that are called myelin. Myelin is very helpful in the correct and appropriate transmission of nerve impulses. Once this sheath is damaged from too much inflammation, multiple sclerosis occurs.

WBC action

T cells, which are special subsets of white blood cells, are important in the development of multiple sclerosis. Normally, the T cells are able distinguish between self and non-self. However, with multiple sclerosis, the T cells become weak when it comes to recognizing and differentiating self and non-self. In fact, in most multiple sclerosis cases, these lymphocytes recognize the healthy cells of the central nervous system as foreign and harmful and attack.

There is a BBB or a blood-brain barrier that serves as a tight barrier between the blood and the brain. This barrier is made up of endothelial cells that completely line the walls of the blood vessels. Since the auto-reactive T cells start attacking healthy cells and trigger an inflammatory process, they tend to cross the BBB, when they are not at all supposed to. This breaks down the BBB, thus, leading to multiple sclerosis.

No comments:

Post a Comment