Paige O. and Janelle H.
What is Multiple Sclerosis?
Your immune system attacks a fatty material called mylein, which covers your nerve fibers (in the CNS) for protection. Without this outer shell, your nerves become damaged and scar tissue may form.
The damage means your brain can no longer send signals through your body in the correct way. Your nerves also don’t function as normal, and cannot help you move and feel. As a result, you may have the following symptoms:
- Trouble walking
- Feeling tired
- Muscle weakness or spasms
- Blurred or double vision
- Numbness and tingling
- Sexual problems
- Poor bladder or bowel control
- Problems focusing or remembering
Often called the "Prime of Life" disease since it usually occurs between the ages of 20-40
"MS Overview and Outlook." WebMD. WebMD, n.d. Web. 13 Nov. 2015.
Genes: Chromosome 6 is affected by M.S. Chromosome 6 is identified as identifying cell functions and roles.
Local and Long Distance Signaling
- Paracrine signaling- A secreting cell acts on nearby target cells by discharging molecules of a local regulator into the extracellular fluid
- Synaptic Signaling- a nerve cell releases neurotransmitter molecules into a synapse, stimulating the target cell.
- Hormonal signaling-specialized endocrine cells secrete hormones into body fluids, often the blood. Hormones may reach virtually all body cells.
With multiple sclerosis, the signaling with the neurons (synaptic signaling) is where the disease forms and attacks the body. Mixed up signals from the neurons can lead to numbness and tingling, or even paralysis (as seen above in the symptoms listed). These symptoms and losses can be temporary or permanent.
"Chapter 11: Cell-to-Cell Signaling." Quizlet. N.p., n.d. Web. 13 Nov. 2015.
Normal Signal Transduction Pathway vs. MS Signal Transduction Pathway
Example: This effect is similar to Christmas lights. If there is a break in the cord then the whole strand of lights will not work
Extracellular Molecules in Signal Transduction
Communication by extracellular signals usually involves six steps:
(2) release of the signaling molecule by the signaling cell;
(3) transport of the signal to the target cell;
(4) detection of the signal by a specific receptor protein;
(5) a change in cellular metabolism, function, or development triggered by the receptor-signal complex
(6) removal of the signal, which often terminates the cellular response.
In animals, signaling by extracellular, secreted molecules can be classified into three types — endocrine, paracrine, or autocrine — based on the distance over which the signal acts.
Lodish H, Berk A, Zipursky SL, et al. Molecular Cell Biology. 4th edition. New York: W. H. Freeman; 2000. Section 20.1
How does this effect M.S?
In M.S, the paracrine signaling is what the disease is effecting. Neuroinflammation has been hypothesized by researchers to take place in the lower locus ceruleus part of the brain. This inflammation is associated with high levels of extracellular ATP which is released from activated cells or leaks from injured or dead cells in the central nervous system. The cells involved in M.S, such as neurons and immune cells, can sense this molecule, as well as other extracellular nucleotides. When extracellular nucleotides build up apoptosis of immune cells begins.
Cieślak, Marek, Filip Kukulski, and Michał Komoszyński. "Emerging Role of Extracellular Nucleotides and Adenosine in Multiple Sclerosis."Purinergic Signalling. Springer Netherlands, n.d. Web. 13 Nov. 2015.
"Neurotransmitters in M.S." ScienceDaily. ScienceDaily, n.d. Web. 17 Nov. 2015.
How cyclic AMP affects cellular biochemical pathwyas in MS
How do Cells Receive Signals?
"Cell Signaling." Nature.com. Nature Publishing Group, n.d. Web. 17 Nov. 2015.