#1 Make Observation
What causes Alzheimer’s disease neurologically? This question came to my mind when I was watching the movie ‘The Notebook’ for the fifth time. Unusual for a guy, I love romantic genre movies and I was wondering why Alzheimer causes short and long term memory loss. I also had an interest on the Alzheimer’s disease after watching the movie ‘Rise of the Planet of the Apes’ where the protagonist tries to fix the neurology nerve system to heal his father’s Alzheimer.
#2 Ask Question
What causes Alzheimer’s disease neurologically?
#3 Create possible explanation
I think the core reason of the Alzheimer’s disease lie on the nerve pathway signal transmission. I think the nerve pathway signal transmission system is same as all of the body functional system and as it grows older and older, the functioning of the specific nerve pathway signal transmission for memories weakens and decreases. #4 Making predictions based on this model
If the problem of the Alzheimer’s disease is in the nerve pathway signal transmission, then the Alzheimer’s disease is indeed a neurological problem. If we can find out the way to re-ignite the signal or heal the receiving or sending parts of the neurological nerve signal system, then we will be able to delay the process of the disease or even fix it permanently.
#5 Test with controls
I do not know the system of the central neurological nerve system of the human nor the treatment of the Alzheimer’s disease. However, to find out numerous people with and without the disease should complete the cause of the Alzheimer’s disease. Run a MRI test on brain of the participants and compare the MRI results with the people with and without the Alzheimer’s disease. If it shows some difference showing the weakening or decreasing of the nerve pathway signal transmission then we can conclude that the neurological nerve pathway signal transmission is the cause of the Alzheimer’s disease. However, we can’t be sure that that is the only causes of the Alzheimer’s disease so we will have to create more experiments.
Alzheimer disease is a neurological disease and it is one of the many forms of dementia. The researches says that the Alzheimer’s disease is the most common form of dementia since its percentage is over half of the total dementia cases. My question was ‘what causes the Alzheimer’s disease neurologically?’ so I decided to first go research about the neuroscience of the human body since the Alzheimer’s disease is primarily the degenerating of the signal pathway system in the brain. The human have a special cell called the neurons in the nervous system and these cells communicate with other cells by synapses. This is the most basic difference between a normal cell and a neuron. Synapses signal can be either chemical or electrical and they are just membrane-to-membrane junctions with such molecular machinery that produces rapid transmission of signals. There isn’t just one neuron in human. In fact, there are hundreds of different types with different functions and shapes.
So all these information led me to an another question of ‘what kind of neurons are related to the Alzheimer’s disease?’ I found out that Alzheimer’s kills neurons due to the accumulation of proteins in the brain. That is why the Alzheimer’s diseases are called the neurodegenerative diseases. I couldn’t specifically find the exact neurons that are related to the Alzheimer’s disease but I found out that the Alzheimer’s kills these neurons in the brain by proteinaceous plaques. An article by ‘Journal of Neuroscience’ did a research on A-beta, a peptide that surrounds the dying neurons in certain regions of the brain. The research said they weren’t sure if the A-Beta is the protein that kills the neurons. A-Beta becomes toxic when it forms an oligomer. Oligomer means a molecule that consists of a few monomer units. A-Beta oligomers are bad for neurons because it causes the neurons to re-enter the cell cycle.
This is bad because once the brain neurons become adult cells, these are not supposed to divide. This is why neuronal cancers are very rare because the neurons cells don’t divide once it reaches adulthood. Then the articles went into deeper matters with mouse models so I stopped my research of A-Beta here. It says that the cause for the Alzheimer’s disease is essentially unknown and all of these researches are part of the hypotheses. There are many hypotheses including the cholinergic and the amyloid hypotheses. But the A-Beta is the most recent hypotheses in the field of science since the A-Beta theory was updated in 2009. Then, I took my TA’s advice and went to find the biology behind the transmission of nerve impulses. Neurons have a part called the dendrites and this is where the neuron fires a correct impulse to another neuron through the axon. Axon is a long projection that connects nerve cells. Just like a normal cell, the neurons have cell membranes as well.
When the neuron is not transmitting impulse, the reason is in its cell membrane. When the neuron cell is polarized, that is when the neuron is inactive. The outside of the cell contains excess sodium ions and the inside of the cell contains excess potassium ions. However, the inside of the cell is negative due to other negatively charged protein and nucleic acid molecules inside the cell. There are Na+/K+ pumps on the membranes and it is permeable! When the neuron gets stimulated, the sodium ions flow in to the cell and the neuron gets depolarized. When the neuron reaches the complete depolarization, impulse is transmitted through the axon and thus makes the cell active. When the impulse fires from a neuron, the other neuron at the end of the axon depolarizes and calcium ions are allowed to enter the cell. Then a chemical called a neurotransmitter is released into the synapse. The neurotransmitter then binds to proteins on the neuron membrane to receive the impulse.
The proteins are the receptors of the many different neurotransmitter and the neurotransmitters does have specific receptor proteins. It is logical that when the neurons die from proteins of the Alzheimer’s disease, the synapses and impulse decreases and decreases. Therefore, I began to have questions about the effect and the symptoms of the Alzheimer’s disease due to the death of many neurons. Alzheimer’s disease equals the loss of neurons and synapses in the cerebral cortex. The most common effect and symptom of the Alzheimer’s disease is the loss of memory and mental skills. The chance of getting an Alzheimer’s disease is higher for older populations. The symptoms advance as the time passes. The speed of the progress of the disorder differs from person to person but most of them start with forgetfulness. It is probably the neuron transmission failure. As the brain neuron dies, the mental state of the human weakens and decreases.
When the Alzheimer’s disease attacks the frontal lobe of the brain, the person’s mood swing can be dangerously unstable. It is because the frontal lobe controls the feeling and the behavior of a person. The person can also have problems with washing and cleaning him/herself because another function of the frontal lobe of the brain is to plan things based on what is wrong and what is right. Also 40% of the Alzheimer’s patients have low appetite in food and have significant weight loss because as the neuron dies, the olfactory and taste nerves fails. All of these symptoms are all directly connected to the problems with the brain neurons. So my first starting question of ‘what causes Alzheimer’s disease neurologically?’ was answered. A simple but sophisticated disruption of a tiny neuron cells in the brain causes the Alzheimer’s disease.
Then I began to think if there are any treatment researches going on in the field of biology. I found one research that caught my eyes and it was stem cells. Professor Kim of the Chung-Ang University in South Korea successfully restored a mouse’s brain function by transplanting a human nerve stem cell. He was able to transplant a stem cell containing acetylcholine, a neurotransmitter, and the articles said that the mouse restored its brain function to a normal state. Professor Kim’s work is also announced in an international journal called ‘Cell Transplantation.’ #7 Repeat (Modify, extend or reject)
‘What is the specific molecule (possibly a protein) that affects the neuron of the brains so it causes the Alzheimer’s disease neurologically?’ and ‘How will transplanting stem cell containing a neurotransmitter called ‘Acetycholine’ affect the human Alzheimer’s disease?’ These are my two refined questions after my exploration of the Alzheimer’s disease.
Reference and Citation
http://scienceblogs.com/purepedantry/2009/02/12/how-does-alzheimers-kill-neuro/ (Authors: N.H. Varvel, K. Bhaskar, A.R. Patil, S.W. Pimplikar, K. Herrup, B.T. Lamb)
http://voices.yahoo.com/the-dreadful-effects-alzheimers-disease-116725.html?cat=70 (Publisher: Carl Kolchack, freelance article writer)
http://blog.naver.com/vitaminmd?Redirect=Log&logNo=110133967592 (Publisher: Vitamin MD)
http://www.medworld.co.kr/news/articleView.html?idxno=63612 (Youn Sang Yong Reporter)