Disease of the Central Nervous System By Eric Nauman Multiple Sclerosis Disease of the Central Nervous System By Eric Nauman

Multiple Sclerosis MS affects the Central Nervous System Immune System malfunctions and attacks myelin Becomes inflamed and detaches from nerve cells Glial cells that produce myelin are also destroyed Scar tissue develops where myelin has been removed The scar tissue is called sclerosis Sclerosis forms on multiple areas of CNS

Central Nervous System Contains the brain and spinal cord Nerve cells are called neurons Neurons are made up of cell body and axons Axons are long extensions of the cell body Transmit impulses and are covered by myelin sheath Nerve impulse Action Potential Nodes of Ranvier

Georgia State University Department of Biology Nerve Cell Georgia State University Department of Biology www.gsu.edu

Myelin Creates a sheath around the axons of cells in the nervous system Made of 80% lipids and 20% proteins Myelin is produced by oligodendrocytes or glial cells Glial cells make up 90% of the cells in CNS while nerve cells make up remaining 10%

Function of Myelin Myelin Insulates the nerves Acts as the insulation on wires Contains ions of the action potential and preserves the impulse Increases speed of nerve impulses Myelinated axons transmit impulses up to 60 times faster than non-myelinated Losing myelin is like stripping the insulation off an electrical wire

Immune System Immune system is made to attack myelin Immune response is driven by a type of white blood cell called a Lymphocyte Thymic or T-Lymphocytes Helper T-Lymphocytes Cytolytic T-Lymphocytes Suppressor T-Lymphocytes B-Lymphocytes antibodies altmed.creighton.edu

Autoimmune Responses Properly functioning immune system must be able to distinguish self from non-self In multiple sclerosis the immune system is used to attack cells of the body Autoimmune Response- an immune response by the body to its own tissues Leads into autoimmune disease Becomes self sustaining Causes structural and functional damage to the body

What Causes Autoimmune Response? The Causes are unknown but there are many theories Malfunctioning immune system caused by genetics Infection by a microorganism Infection by a virus Others believe a combination of several Viral infection early in life leads to genetic mutation and immune malfunction

Genetics of Multiple Sclerosis Multiple sclerosis is thought to be genetically related Genes affect risk and course disease takes Entire genome screened 60 genomeric regions related to MS Chromosome 6 is thought to be linked to MS

Statistics 300,000 Americans and 2.5 million people around the world have multiple sclerosis Caucasians are more at risk than other races More common in temperate climates Women are 3 times more likely to develop MS Symptoms begin showing ages 20 to 40 Relatives of MS patients are at higher risk MS is not directly inherited from parent to child

Types of Multiple Sclerosis Relapsing Remitting 85% of patients have this form Flare ups followed by periods of recovery Primary Progressive Slow and steady progression of symptoms Recovery periods are rare Progressive Relapsing One of the most aggressive forms of MS Steady worsening of Symptoms Secondary Progressive Half of patients with relapsing remitting will develop this type within 10 years Steady Progression of Symptoms

Symptoms Early symptoms of MS include: Later symptoms include: Numbness in 1 or more limbs Partial paralysis Double or blurred vision in 1 eye Later symptoms include: Loss of coordination Loss of ability to walk or stand upright Loss of bladder or bowel control Mental symptoms: Depression, Forgetfulness, Loss of Concentration

Diagnosis Multiple Sclerosis is hard to diagnose There are no definitive lab tests for MS MRI and examination of cerebrospinal fluid Poser Criteria for diagnosis of Multiple Sclerosis Bases on laboratory tests and evidence of flare ups and attacks 4 criteria Clinically definite MS, laboratory supported MS, clinically probable MS, and laboratory supported MS

Treatments No cure for MS Disease Modifying Drugs Beta Interferons Glatiramer Mitoxantron Drugs used to fight symptoms Alternatives to Drugs Plasmaphoresis

Prognosis Most MS patients confined to a wheelchair within 15 years Life expectancy 25 to 35 years after onset of symptoms Many deaths of MS patients result from complications due to secondary symptoms Difficulty swallowing Asphyxiation