Multiple Sclerosis (MS) XXXXXXXXX XXXXXXXXXXX XXXXXX Course: Biology 1407 Instructor: Dr. Nesterovitch Semester: Spring 2010 Houston Community College

Multiple Sclerosis: An Overview In this presentation, you will be given an overview of the disease, Multiple Sclerosis. The following topics will be covered: MS: What Is It? Possible Causes of MS Symptoms of MS Disease Courses of MS Methods of Diagnosis MS Research

MS: What Is It? An autoimmune disease (self attacks self) Attacks the Myelin Sheath that protects and insulates the axon portion of neuron cells

MS: What Is It? Axons are demyelinated and damaged Scar tissue (sclerosis) develops in the damaged areas Electrochemical signals normally travelling along the axons are hampered or blocked

MS: What Is It?

MS: What Is It? Attacks the Central Nervous System (CNS) only Brain Spinal chord Optic nerves Not evident in the Peripheral Nervous System.

Possible Causes of MS Immunologic: MS is believed to be an autoimmune response T-Cells attack the Myelin Exact markers or targets on Myelin are unknown Researchers have begun to identify the receptors on the T-Cells Could possibly lead to immunotherapy that targets specific receptor

Possible Causes of MS Immunologic: Weakness in Blood-Brain Barrier might play a role Allowing uncontrolled T-Cell release into the CNS

Possible Causes of MS Environmental MS Clusters (groups and/or time periods where higher rates of MS occurred) MS Clusters, and their associated environments, are under study but have not yielded conclusive evidence Hemispheric proximity MS is known to occur in higher rates farther from the equator. Possible link to Vitamin D/Sunlight exposure levels

Possible Causes of MS

Possible Causes of MS Genetics Not statistically a hereditary disease Yet a higher rate of disease contraction in direct family members (parents, siblings, children) of a diagnosed patient 1-3% in families compared to 0.1% in general population

Possible Causes of MS Genetics Increased frequency of specific Human Leukocyte Antigen (HLA) alleles found in MS patients compared to population HLA: genetically determined proteins that influence immune systems and are found on Chromosome 6

Possible Causes of MS Infectious No causal link established between viruses and the onset of MS Studies are being conducted, however, on certain viruses (observed to have some effect on Myelin on their own) that may be part of a combination of triggers that causes a patient to have MS Epstein-Barr Virus has been observed to have a closer relationship to MS in some patients, but no direct cause has been established.

Possible Causes of MS Summary of Possible Causes: To date, the exact cause of MS has not been established. It is thought that MS might arise from a combination of triggers, such as both environmental and viral. Scientists continue to work to establish causal factors while also focusing on treatments focusing on the known element: the immune response (attacking the self).

Symptoms of MS (more common) Numbness or weakness in limbs On one side of body or on whole of lower body Partial or complete loss of vision Usually in one eye at a time Pain often accompanies eye movement Double vision or blurring of vision Tingling or pain in parts of body

Symptoms of MS (more common) Electric shock sensation with certain head movements Lack of coordination or unsteady gait Fatigue Dizziness and vertigo Bladder or bowel dysfunction

Symptoms of MS (more common) Decrease in cognitive function performance Sexual dysfunction Emotional changes and depression Spasticity

Symptoms of MS (less common) Speech disorders Swallowing problems Headache Hearing loss Seizures and tremors Respiration/breathing problems Itching

Symptoms of MS Signs and symptoms of MS vary widely among patients, depending on the location of the affected nerve fibers in the CNS Some symptoms will come and go, while other symptoms are more lasting Increases in body temperature tend to trigger or worsen symptoms in MS patients

Symptoms Summary

Courses of MS Relapsing-remitting (RR) MS Primary-progressive (PP) MS MS symptoms are first observed as a series of symptomatic attacks followed by a remission period. After a period of stability, the symptoms later return Primary-progressive (PP) MS After initial attacks, the patient experiences clinical decline with no apparent remission phases

Courses of MS Secondary-progressive (SP) MS Begins with a RR MS course and then follows with a PP MS course Progressive-relapsing (PR) MS Begins with a progressive path interspersed with higher acute attacks This course is rare in the patient population

Courses of MS Approximately 20% of diagnosed patients have a benign form of the disease After the initial acute attacks, the symptoms never return, and the patients have fully functional lives A small percentage experience swift decline leading to significant disability or death soon after onset. Overall, however, MS is rarely fatal, and patients have a fairly normal life expectancy

Methods of Diagnosis Note: One method alone is not a final determination of a MS diagnosis, but instead a combination of methods is used to rule out the possibility of other diseases

Methods of Diagnosis Medical history Investigating family history, places and dates of travel, birthplace, etc.

Methods of Diagnosis Neurologic exam Testing functions of speech, vision, balance, and other motor skills and sensory functions Evaluating mental and emotional changes

Methods of Diagnosis Magnetic Resonance Imaging (MRI) Searching for locations, growth patterns, and timeline of scarring and lesions

Methods of Diagnosis Visual Evoked Potential (VEP) Used to find impaired electrochemical response times along the optic nerve pathways Slowed or impaired responses signify demyelination along the nerve fibers

Methods of Diagnosis Cerebrospinal Fluid analysis Measuring levels of: Immune response antibodies Proteins called oligoclonal bands Breakdown proteins from damaged Myelin

Current MS Treatments There is no cure for MS Due to risks and side effects, many MS patients do not use currently offered medications Steroids, such as prednisone, are used by some patients to reduce severity and duration of attacks Not recommended for long term use due to possible side effects of weight gain, acne, seizures, and psychosis

Current MS Treatments Three forms of beta interferon are currently FDA-approved and have been observed to: Reduce the number of exacerbations of attacks Reduce the time and severity of attacks May slow the progression of physical disability Possibly decreases myelin destruction Side effects of beta interferon: fever, chills, sweating, muscle aches, fatigue, depression, injection-site skin reactions

MS Research An organization called the Myelin Repair Foundation sums up the areas of current MS research. After reading each research area in the following slides, refer to the corresponding number in the chart following the listed research areas.

MS Research “Understanding how oligodendrocytes are normally generated from neural stem cells and how multiple sclerosis perturbs this process.”

MS Research “Understanding the underlying mechanism of myelination and how it is perturbed in multiple sclerosis.”

MS Research “Understanding how nodes of Ranvier and paranodes are normally formed and how they are perturbed in multiple sclerosis.” “Understanding the immune response in multiple sclerosis and how inflammation affects myelin repair. “

MS Research “Understanding how the Blood-Brain Barrier is affected in multiple sclerosis and its role in the disease.” “Development of better animal models for study of multiple sclerosis and remyelination.”

MS Research

MS Research Research goals: Promote myelin repair at targeted locations Gain control of the immune response that is currently damaging myelin Prevent inflammation during myelin repair Fortify the Blood-Brain Barrier

Conclusions Multiple Sclerosis is a disease that is rarely fatal yet causes years of pain and discomfort for most patients. The cause of MS in a patient is unknown. A combination of triggers is a possibility. The current treatments for MS focus on symptom management. Research scientists are aggressively pursuing several pathways to possible cures and treatments for the disease.

References/Bibliography National Multiple Sclerosis Society www.nationalmssociety.org Multiple Sclerosis: Hope Through Research. National Institute of Neurological Disorders and Stroke http://www.ninds.nih.gov The Merck Manuals: Online Medical Library http://www.merck.com/mmpe/index.html

References/Bibliography Multiple Sclerosis and Epstein-Barr Virus. Lynn I. Levin, PhD, MPH; Kassandra L. Munger, MSc; Mark V. Rubertone, MD, MPH; Charles A. Peck, MD; Evelyne T. Lennette, PhD; Donna Spiegelman, DSc; Alberto Ascherio, MD, DrPH. Journal of the American Medical Association. 2003; 289: 1533-1536  The Mayo Clinic www.mayoclinic.com The Myelin Repair Foundation www.myelinrepair.org