Transcript Multiple Sclerosis

Christiane’s part
In Multiple Sclerosis (or "MS") a loss of
the nerves' axon coating myelin
prohibits the nerve axons from
efficiently conducting action and
synaptic potentials. Scar tissue (called
plaques or lesions) forms at the points
where demyelination occurs in the brain
and spinal cord, hence the name
"Multiple Sclerosis” or "many scars” The
demyelination found in MS is thought to
be caused by an autoimmune process, in
which the body's immune system attacks
its own healthy tissue
 In MS, an unknown trigger activates helper T-cells whose antigen specific receptors
recognize central nervous system myelin as an antigen. While what exactly
activates these T-cells is unknown, but there is speculation that the trigger may be
environmental or viral. Once triggered, the activated T-cells reproduce clones that
have the same myelin-specific activation. All of the activated T-cells then release
cytokines and adhesion molecules that enable the T-cells to adhere to and cross
over the blood-brain barrier, which normally prohibits the flow of substances into
the brain
 The proteins in these T-cells bind to myelin fragments on microglial cells and
undergo a secondary activation, after which they multiply and release more
cytokines, further invading the nervous system and inflaming and damaging the
blood-brain barrier. The greatly weakened barrier becomes easily permeable,
allowing additional immune system cells, such as B-cells and cytotoxic T-cells to
cross over. Once through the barrier, B-cells produce antibodies which bind to the
oligodendracytes (the cells of the CNS which create myelin) and the myelin itself.
Associated macrophages procede to destroy the myelin and may also damage the
oligodendracytes
 By lowering the rate at which the axonal membrane absorbs nerve impulses,
myelin acts as an insulator, allowing NS potentials to travel rapidly through the
nervous system and maintain communication between the brain and the rest of the
body. This communication between the brain and the rest of the CNS and
peripheral nerves is a central component of the proper functioning of the body's
sensory and motor capabilities. As the myelin is destroyed, the CNS loses some of
its ability to send signals throughout the body, causing the debilitating symptoms
of MS
 MS has its most striking effect on motor and sensory neurons, which generally have
long axons carrying information between the brain, spinal cord, and the rest of the
body. Because these axons are longer, they have a greater need for the insulation
myelin provides and are therefore most strikingly affected by its destruction. The
most common symptoms and effects of MS demonstrate sensory or motor neuron
failure
 Coordination, speech, and bladder control are adversely affected when there is a
breakdown of the function of motor neurons that carry signals from the brain and
spinal cord to the muscles, which normally perform these functions.
 https://www.youtube.com/watch?v=Naecv3h868c
 Scientists researching treatments, forms of prevention and cures for MS are looking
at two different areas: the possible causes of MS and ways to repair the damage to
myelin and nerve cells. Determining the cause or trigger for MS will help to both
better understand the disease and develop refined treatments and determine ways
to avoid or prevent the disease before it occurs. Reversing or eliminating the
diseases effects will, of course, help those who already suffer from MS.
 Physical therapy and medications that suppress the immune system can help with
symptoms and slow disease progression
 Corticosteroids, such as oral prednisone and intravenous methylprednisolone, are
prescribed to reduce nerve inflammation. Side effects may include insomnia,
increased blood pressure, mood swings and fluid retention.
 Plasma exchange (plasmapheresis). The liquid portion of part of your blood
(plasma) is removed and separated from your blood cells. The blood cells are then
mixed with a protein solution (albumin) and put back into your body. Plasma
exchange may be used if your symptoms are new, severe and haven't responded to
steroids.
 No therapies have shown benefit for slowing the progression of primary-
progressive MS
 Many of the disease-modifying therapies used to treat MS carry significant health
risks. Selecting the right therapy for you will depend on careful consideration of
many factors, including duration and severity of disease, effectiveness of previous
MS treatments, other health issues, cost, and child-bearing status.
 Beta interferons. These medications are among the most commonly prescribed
medications to treat MS. They are injected under the skin or into muscle and can
reduce the frequency and severity of relapses.
 Physical therapy. A physical or occupational therapist can teach you stretching
and strengthening exercises and show you how to use devices to make it easier to
perform daily tasks. Physical therapy along with the use of a mobility aid when
necessary can also help manage leg weakness and other gait problems often
associated with MS.
 Muscle relaxants. You may experience painful or uncontrollable muscle stiffness
or spasms, particularly in your legs. Muscle relaxants such as baclofen (Lioresal)
and tizanidine (Zanaflex) may help.
 Medications to reduce fatigue.
 Other medications. Medications also may be prescribed for depression, pain,
sexual dysfunction, and bladder or bowel control problems that are associated with
MS.
 Activities such as exercise, meditation, yoga, massage, eating a healthier diet,
acupuncture and relaxation techniques may help boost overall mental and physical
well-being, but there are few studies to back up their use in managing symptoms of
MS.