Introduction
Multiple sclerosis (MS) is a devastating demyelinating disease affecting the central nervous system (CNS) and resulting in impaired motor and sensory function (Karussis, 2014, p. 134). MS is characterized by three main features: inflammation, and the resulting demyelination and axonal damage (Karussis, 2014, p. 134). An inflammatory response is initiated when T cells attack myelin, recognizing self-antigens as foreign (Karussis, 2014, p. 134). The inflammatory response propagates demyelination and axonal damage (Karussis, 2014, p. 135). A major cell involved in the pathogenesis of MS, oligodendrocytes (OLs) are responsible for creating myelin (Zhang et al., 2009, p. 19162). MS patients present with reduced numbers of OLs, resulting in less production of myelin and impaired speed of neural transmission (Karussis, 2014, p. 134). In initial stages of the disease, remyelination occurs; however, as MS progresses, OLs become less able to repair the damage (Zhang et al., 2009, p. 19162).
Notch1 and its ligand, Jagged1, have been identified as critical mediators of oligodendrocyte progenitor cell (OPC) recruitment and differentiation (Zhang et al., 2009, p. 19162). OPCs are recruited to demyelinated axons, where they differentiate into OLs, producing myelin to remyelinate CNS axons (Jurynczyk & Selmaj, 2010, p. 7). Notch1 receptors are found on OPCs and Jagged1 ligands are present on adjacent axons and glial cells (Woodhoo et al., 2009, p. 841). MS lesions have characteristically high numbers of Notch1 receptors; additionally, Jagged1 is also abundant in MS lesions (Stidworthy et al., 2004, pp. 1931-1934). Interactions between Notch1 and Jagged1 result in the failure of OPCs to differentiate into OLs, in turn impairing OPC...
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... p. 134). The Notch1/Jagged1 pathway is extensively involved in demyelination and, as such, is a therapeutic target for remyelination of CNS axons in individuals with MS (Zhang et al., 2009, p. 19162). Through a cascade of intracellular events, the binding of Jagged1 to Notch1 induces the suppression of transcription factors that prevent the differentiation of neural precursor cells to OPCs (Aparicio et al., 2013, p. 820). Consequently, the OPCs cannot undergo further maturation into OLs, resulting in impaired ability to repair demyelinated axons (Aparicio et al., 2013, p. 829). The Notch1/Jagged1 pathway is ideal as a therapeutic target for remyelination, as there are several steps that can be interfered with (Zhang et al., 2009, p. 19162). Impairment of the Notch1/Jagged1 pathway allows for OL maturation and the resulting remyelination (Perez et al., 2013, p. 273).
Oligodendrocyte- forms myelin sheath in the central nervous system cells, won’t repair damaged axons, exists in the CNS
Multiple sclerosis (MS) is a disease affecting the myelination of the central nervous system, leading to numerous issues regarding muscle strength, coordination, balance, sensation, vision, and even some cognitive defects. Unfortunately, the etiology of MS is not known, however, it is generally thought of and accepted as being an autoimmune disorder inside of the central nervous system (Rietberg, et al. 2004). According to a study (Noonan, et al. 2010) on the prevalence of MS, the disease affects more than 1 million people across the world, and approximately 85% of those that are affected will suffer from unpredictably occurring sessions of exacerbations and remissions. The report (Noonan, et al. 2010) found that the prevalence of MS was much higher in women than in men, and that it was also higher in non-Hispanic whites than in other racial or ethnic groups throughout the 3 regions of the United States that were studied.
Multiple sclerosis (MS) is generally thought to be an autoimmune disease that attacks the myelin sheaths, or oligodendrocytes that cover nerve axons in the central nervous system (PubMed Health 2013). This immune response causes inflammation, which triggers immune cells to destroy axons “along any area of the brain, optic nerve, and spinal cord” (PubMed Health 2013). When the myelin sheath “is damaged, nerve signals slow down or stop” thus hindering the propagation of action potentials and limiting function (PubMed Health 2013).
Emerging evidence implicates microglial play critical roles to the CNS development of the brain. Microglial are unique population arise from immature yolk-sac macrophages that migrate and colonize the developing brain (Ginhoux et al., 2010; Ransohoff and Cardona, 2010). Interestingly, microglial (or their precursor cells) are selectively integrating into proliferative neurogenic zone of the proliferation and regulating the size of neural precursor cell pool via phagocytose neural precursor cell upon completion of neurogenesis(Cunningham et al., 2013). Also, colonization of microglia in the developing brain almost concurs temporally with brain vascularisation, neuroepithelial-radial glia transformation, neuronal migration, and myelination. Recent advent of transgenic technology and pharmacology allowed the role of microglia during development and their correlation with neural development disorder to be investigated extensively. For instance, pharmacologically knockout or inactivation of embryonic microglia resulted in increases of neural precursor cells pool (Cunningham et al., 2013). Similar phenomenons were also observed in genetically knockout of microglial in mice. Colony stimulating factor 1R-deficient (Csf1r−/−) mice w...
Multiple sclerosis is a chronic degenerative disease of the central nervous system, in which the myelin that covers the nerves is somehow eaten away and scar tissue for multiple sclerosis in its place, interrupting the nerve’s signals. This disease has an unpredictable and uncontrollable course which leads to the loss of vision, hearing, speech, the ability to walk, control of bladder and bowels, sensitivity to touch, vibration and pain, potency and coordination of movements. The list of possibilities is lengthy and horrifying.
According to National Multiple Sclerosis Society, Multiple Sclerosis (MS) is an unpredictable, often disabling disease of the central nervous system (CNS) that disrupts the flow of information within the brain, and between the brain and body. The central nervous system (CNS) comprises of the brain and the spinal cord. CNS is coated and protected by myelin sheath that is made of fatty tissues (Slomski, 2005). The inflammation and damage of the myelin sheath causing it to form a scar (sclerosis). This results in a number of physical and mental symptoms, including weakness, loss of coordination, and loss of speech and vision. The way the disease affect people is always different; some people experience only a single attack and recover quickly, while others condition degenerate over time (Wexler, 2013). Hence, the diagnosis of MS is mostly done by eliminating the symptoms of other diseases. Multiple sclerosis (MS) affects both men and women, but generally, it is more common in women more than men. The disease is most usually diagnosed between ages 20 and 40, however, it can occur at any age. Someone with a family history of the disease is more likely to suffer from it. Although MS is not
Multiple Sclerosis (MS) is a complicated chronic deteriorating disease that has an effect on the central nervous system (CNS). This disease causes destruction of the myelin around the nerve fibers. “The exact etiology of Multiple Sclerosis is unknown; however, it is thought to be an immune mediated disease. MS is characterized by CNS inflammation, demyelination, and axonal loss” (Compston & Coles, 2008). Typically, it is described by early relapses and remissions of neurological signs of the CNS. This is known as relapsing-remitting MS (RRMS). MS can be identified by a variety of known risk factors. Multiple Sclerosis can be brought on by a mixture of inherited and environmental risk factors such as smoking or an exposure to a virus like Epstein Barr. The inflammatory process has an interesting role on the central nervous system.
Primarily, the term MS refers to a chronic disorder that attacks the central nervous system (CNS). It is most common in temperate continents such as Europe and Australia with Asiatic and African continents having a lower risk of the disease (Wiley Online Library, 2013). A search organised by the Multiple Sclerosis Society (2013) has estimated that there are 127,000 people living with MS in the United Kingdom. Further research by Chipps, Clanin, and Campbell (1992, pp. 158-167) shows that MS disorder more likely affects women than men with its symptoms occurring between the ages of 20 and 40 in most cases and is quite uncommon in childhood and old age. The nerve cells known as neurons in the brain constantly transmit and receive signals. They invoke emotions, activities and cognition that constitute the day to day experiences of humans. Under normal circumstances, these signals travel on a protected insulation path known as the myelin sheath. This insulation is vital as it enables signals to reach their target. In Multiple Sclerosis, the myelin sheath gets disintegrated causing the nerve fibre to be damaged leading to a disruption in the abili...
Multiple sclerosis is a chronic disease of the central nervous system. It is understood as an autoimmune disease, a condition where the body’s immune system mistakenly attacks normal tissues. In Multiple Sclerosis, the patient’s own cells & antibodies attack the fatty myelin sheath that protects and insulates nerve fibres in the brain and spinal cord, the two components of the CNS. This ultimately causes damage to the nerve cells and without the insulation the myelin sheath provides, nerve communication is disrupted. Hence, Multiple Sclerosis is characterized by symptoms that reflect central nervous system involvement (Luzzio, 2014).
Multiple sclerosis is an autoimmune disease that involves the different areas of the central nervous system, the brain, and spinal cord. It damages the myelin sheath, the material that surrounds and protects the
Multiple Sclerosis is a nervous system disease that affects the spinal cord and the brain by damaging the myelin sheaths that protects nerve cells. Destroyed myelin prevents messages from communicating and sending properly from the brain, through the spinal cord, to internal body parts. In the United States, more than 350,000 people are diagnosed with this disease. Anyone can get this disease, but it is more common among Caucasian women. MS symptoms begin between the ages 20-40 and are caused by nerve lesions being present in multiple areas of the Central Nervous System, symptoms differ on the lesion’s location.
Sharp, J., Frame, J., Siegenthaler, M., Nistor, G., Keirstead, H.S. (2010). Human Embryonic Stem Cell-Derived Oligodendrocyte Progenitor Cell Transplants Improve Recovery after Cervical Spinal Cord Injury: Stem Cells, 28, 152 – 163.
Multiple Sclerosis (MS) is a chronic, progressive, unpredictable disease that affects the central nervous system. It is thought to be an immune-mediated disorder, MS causes the immune system to attack the healthy tissue in the central nervous system. This particular disease is most common further from the equator, in places such as North America, Southern parts of Australia, and Northern Europe. Some researchers believe if you live close to the equator, your chances of developing MS significantly decreases. This is due to high levels of vitamin D, also known as the sunshine vitamin. Multiple Sclerosis can affect any age group, but is most common in people aged 20-50. Children as young as 2 can be diagnosed. Women are more susceptible to developing MS than men
Multiple Sclerosis (MS) is a debilitating autoimmune disease. The Central Nervous System (CNS) is attacked by the immune system; creating lesions that interrupt the correct signaling of nerves, spinal cord, and brain (Frankel, & James, 2011). Inhibiting development of this disease is crucial for maintaining quality of life and fatigue for individuals with MS. There has been vast amount of research on the effect of various exercise training programs, and their benefits for MS (Motl, & Gosney, 2008, Krupp, 2003, Chen, Fan, Hu, Yang, & Li, 2013). Balance, aerobic, and strength training have been the main focus of most researchers; causing an interest in what training mode is most effective for improving quality of life and lower fatigue. It is critical to examine and contrast the effectiveness of a variety of exercise programs, because if training is completed effectively it can drastically improve quality of life and fatigue for individuals with MS.
damaged or lost cells, and enabling the new neurons to integrate effectively into the brain,