The first time I heard of Parkinson’s disease was when I watched an interview of Michael J. Fox. I was a huge Back to the Future trilogy fan. I remember seeing his tremors, and learning about the disease. It wasn’t until my great-uncle had been diagnosed did it become personal. It very difficult for people to see those you love suffer with something they can’t control. It’s important that we learn about this disease, so we can find a cure.
Parkinson’s disease is a neurodegenerative disorder. It is the second most common one behind Alzheimer’s disease. It is characterized by the loss of dopamine neurons in the substantia nigra, a specific area in the brain. The figure below highlights this area and compares a healthy brain and a brain with Parkinson’s disease. The disease has both motor and non-motor symptoms. The motor symptoms include rigidity, tremors, and posture change. I had known about these but was surprised about the non-motor symptoms. Some of those symptoms are olfactory deficits, constipation, rapid eye-movement, sleep behavior disorder, and depression. The medical field believes that if they could give an early diagnosis if they can recognize these symptoms as a part of Parkinson’s disease.
After some research, it seems like Parkinson’s is more like a combination of diseases under one name. I’ll highlight a couple of the important pathways that contribute to Parkinson’s disease. Glutamate excitotoxicity is one route. Glutamate is a neurotransmitter that allows calcium to enter. When there is too much glutamate, too much calcium enters. This leads to the mitochondria, the organelle that helps with energy production, becoming stressed (oxidation stress). This causes neurodegeneration. Another pathway includes the accumalation of proteins. Mutations can cause proteins to be folded incorrectly and enzymes not to work properly. This causes the proteins to tangle together and there isn’t anything to clean it up. This can cause oxidative stress just like the glutamate pathway, and leads to neurodegereation. The last pathway I’ll talk about is inflammation. When the brain experiences trauma, it becomes inflamed. The brain tries to fix itself, it can causes oxidative stress too.
To prevent Parkinson’s disease and treat the symptoms, research has gone into neuroprotection. These involve dopamine agonist, antioxidants, MAO inhibitors, and agents that affect mitochondrial function. They all try to prevent the initiation of the pathways that I previously highlighted. One interesting neuroprotector is estrogen. Men are more likely to have Parkinson’s than women, and this is due to estrogen. Estrogen has possible antioxidant effects and can inhibit glutamate receptors. While estrogen seems like a great treatment, it can increase the chance of breast cancer and coronary heart disease. Many people suffer from this disease, and we’re just beginning to understand it. We must continue this research and look for a solution for those who suffer with this disease.
Resources:
https://moodle.cord.edu/pluginfile.php/390935/mod_resource/content/2/bipolar.pdf
http://neurochemistry2014.pbworks.com/w/page/88087888/Parkinson%20disease%3A%20from%20pathology%20to%20molecular%20disease%20mechanisms
http://www.healthcentral.com/ency/408/guides/000051_1.html
A Look at Parkinson's Disease
