Multiple sclerosis, which is abbreviated MS, is an inflammatory disease that involves the damage of the fatty myelin sheath surrounding brain axons, as well as the spinal cord. The damage results to the demyelination of the axon scarring including a wide range of symptoms. The disease is also referred to as encephalomyelitis disseminate or disseminated sclerosis (Compston and Coles). The first instance of the disease was reported by Jean-Martin Charcot in 1868. The onset of the disease is mainly seen young adults and is mainly common in women. MS has a prevalence of between 2 to 150 people in a population of 100,000 people. The meaning of the name multiple sclerosis is to scars especially in the white matter that is in the spinal cord, as well as brain mainly made of myelin.
Multiple sclerosis has an effect on the ability of the cells of the nerve that are located in the brain and the spinal cord to have effective communication with the other cells. Communication of the nerve cells occurs by sending electrical signals known as action potential through long fibers called axons. The axons are contained in an insulating material that is known as myelin. In a situation where the disease has occurred, the immune system in the body attacks the myelin s leading to their destruction. The loss of myelin reduces the efficacy of the axons in conducting signals. The mechanisms behind the disease process are well known although the real cause for the disease is unknown. Some of the main theories proposed include genetic factors and infections. There are environmental factors that have been identified as causes for the disease (Compston and Coles).
An individual having multiple sclerosis may undergo almost any of the neurological signs or symptoms such as sensational changes. The individual may loss sensitivity or tingling, numbness, prinking, weakness in the muscles, clonus, movement difficulties and muscle spasms. The individual may also experience coordination and balance difficulties speech problem or dysarthria and problems in swallowing also called dysphagia. The individual may also suffer from acute and chronic pain, visual problems, fatigue, and difficulties in the bladder and bowel (Compston and Coles). The patients also experience cognitive impairment that is of varying degrees and other emotional depression symptoms or even unstable moods.
Multiple sclerosis mainly appear in worsening periods of episodic acute also called relapses, bouts, attacks or relapses, progressive neurologic function deterioration or combination of the two. The occurrence of relapse in MS is usually unpredictable and may take place without giving any warning or the obvious inciting factors (Compston and Coles). There are, however, some attacks that start with some common triggers. The occurrence of relapses takes place in a more frequent way during the summer and spring. There is a possibility for the viral infections to increase relapse risk. These viral infections include influenza and cold. Stress is another factor that may trigger an attack with pregnancy having an effect on relapse susceptibility. There is an increase in the relapse risk after a woman has delivered (Compston and Coles). There is no evidence on pregnancy having an influence on long-term disability. In addition, no evidence exists on the fact that vaccination, physical trauma, or breasts are triggers of relapse (Compston and Coles).
There is a strong believe that MS is an immune-mediated disorder mainly by a complex interaction of the genetic of the individual and environmental insults that are not identified. There is a belief that the damage is due to the immune system of an individual which attacks the nervous system. Some of the targets of the immune response that may be attacked include the proteolipid protein (PLP) and myelin basic protein (MBP). However, the role of myelin basic protein in MS is still facing controversies since it is buried in the myelin sheath there the immune cells may not be able to recognize. In the recent studies, there are suggestions on the role of myelin lipid in the development of multiple sclerosis.
There has been an assumption that the target for myelin was a protein even when it is clear that the myelin sheath is composed of almost 80% lipid. Lipids are also known to be targets for other prominent autoimmune conditions affecting the nervous system such as Guillain-Barre Syndrome. Autoimmunity usually arises in situations where the immune cells that recognize foreign antigens start reacting with self antigens. When this occurs, the process is referred to as molecular mimicry (Wucherpfennig and Strominger).
The current research on MS is mainly directed to the treatment of the disease. Research is being done to get the most effective, tolerable and convenient treatment. There is also focus on the creation of treatments for the progressive subtypes, strategies for neuroprotection, as well as an effective treatment for the symptoms (Cohen). There are various treatments that may fight the attack or offer improved function that are investigation. Some of the agents that have promising ends include rituximab, alemtuzumab, dirucotide, daclizumab, and teriflunomide.
There is evidence that MS is related to the deficiency of vitamin D and has, therefore, been proposed as an agent of treating the disease. However, clinical trials on the agent have been scarce with no clear indication of any success. While there is low evidence that low dose of naltrexone may be beneficial, only results that were generated from a pilot study focusing on the primary progressive multiple sclerosis have been published (Cree, Kornyeyeva and Goodin).
The other are of research that has gained much interest is the area of disease biomarkers. This has been as a result of the lack of variable clinical MS presentation, as well as, the lack of tests for diagnosing test that can be performed in the laboratory in order to test the disease. This has lead to delays in getting diagnosis coupled by the failure to predict the diagnosis. Some of the new diagnostic methods that are being investigated include working with anti-myelin antibodies, of microarray analysis of gene expression, as well as the studies with cerebrospinal fluid and serum. However, none of these has yielded positive results that are reliable (Harris and Sadiq).
Research on evolution prediction is being done in order to help monitor the activity of the disease. Some of the disease activation biomarkers include osteopontin, interleukin-6, nitric oxide synthase, and fetuin-A (Harris and Sadiq). Since the progression of the disease leads to neurodegeneration, there are investigations that are focused on the roles of proteins that are indicative of axonal, neuronal, and glial loss like the neurofilaments and N-acetylaspartate. There are also biomarkers that are aimed at differentiating those who are responding to medication from those who are not responding (Harris and Sadiq).
There are various therapies that are under investigation for the treatment of multiple sclerosis. Some of these medications are aimed at improving the function, limit the progression and curtail attacks. Most of the treatments that are in clinical trials include those drugs that are being used in the treatment of other diseases. There is also research on a combination of medications that are currently being employed in the treatment of multiple sclerosis. More work is being done in understanding the disease in a better way that may result to the development of new treatments.
The other main research is focusing on the drugs that modify the disease course rather than targeting symptoms or the relapses recovery. There are numerous clinical trials that are underway where new treatments are being devised with some being tested in animal models. There have been reported detectable amount of Chlamydophila pneumoniae DNA in samples of cerebral fluid taken from the patients. This has resulted in the use of antimicrobial agents that fight against Chlamydophila pneumoniae (Sriram, Yao and Stratton).
The use of antioxidants has been linked with a reduction in the permeability, in the blood-brain barrier. Patients of MS who take the supplements have low uric acid levels, a natural antioxidant (Oztaş, Kiliç and Dural). It has been reported that an increase in the uric acid levels offer protection to the destruction of the blood-brain barrier through the scavenging of peroxynitrite. The presence of Peroxynitrite has been linked to the degradation of the axons degeneration thus its removal may offer protection to the axon when an attack takes place. Bilirubin has also been indicated to be a possible treatment due to its immunomodulatory properties (Liu, Li and Lu). A number of combined therapies have been tested including those of drugs that have been approved. Some of the combinations that have good results are the combination of Copaxone and Minocycline (Metz, Li and Traboulsee).
In conclusion, Multiple sclerosis as an inflammatory disease affects mainly the axons that are in the brain and the spinal cord. The disease causes demyelination slowing down the messaging of information between the brain and the rest of the body. Some of the symptoms include visual disturbances, coordination difficulties, weakness of the muscles and thinking problems. Numerous researches on the treatment and diagnosis of the disease is currently being done to improve the treatment as well as diagnosis techniques.
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