Sunday, October 17, 2010

"Parkinson's Disease: Working Towards a Cure": Part 1-- The Basics

This is the first post from a three part series written by Andrew Greene, a graduate student at McGill University studying Parkinson's Disease. 

James Parkinson was a British apothecary-surgeon best known for his medical report entitled "An Essay on the Shaking Palsy." Published in 1817, it was a detailed description of the disorder that would one day be known as Parkinson's disease. The disease can bring on a variety of symptoms, many of which we're only just beginning to appreciate, but the best understood are the movement related effects. Typical symptoms include tremors of the limbs and difficulties performing movements, especially ones that have multiple parts, such as reaching out to a cup, grabbing it, and bringing it to your lips. There is presently no cure for Parkinson's disease, but there are a number of treatments available to at least temporarily alleviate the symptoms, and these will be discussed in detail in part 2.
Despite the fact that Parkinson's disease is primarily a movement disorder, the muscles themselves generally remain healthy. It's actually a part of the brain involved in coordinating movement that has traditionally been said to be most prominently affected by the disease. This part of the brain is called the substantia nigra, which means black substance, referring to its characteristic dark colour compared to surrounding brain regions. The substantia nigra is located near the center of the brain and contains neurons that secrete a chemical called dopamine. Dopamine is a type of neurotransmitter, which are a class of chemicals that neurons emit in order to communicate with each other.
Dopamine is best known for its role in the brain's reward system, in which it's used to provide feelings of pleasure and enjoyment in response to things such as food, sex, and certain drugs. However, dopamine released by the substantia nigra also plays a critical role in modulating the activity of the striatum, a brain region that is essential in planning and coordinating movements. The striatum is the origin of two neural pathways that exert opposite effects on movement. The first of these is the so called direct pathway, which is thought to facilitate and reinforce intended movements. The second is the indirect pathway, which is thought to be responsible for inhibiting unwanted or inappropriate motion. Dopamine released by the substantia nigra helps maintain a balance between these two pathways by increasing the activity of the former and decreasing the activity of the latter.
In Parkinson's disease the dopamine-emitting neurons of the substantia nigra die off, which tips the delicate balance between the direct and indirect pathways. The result is too much activity in the indirect, motion-inhibiting pathway and too little in the direct, motion-facilitating pathway, which ultimately makes it exceedingly difficult for a patient to move. Why dopamine-emitting neurons of the substantia nigra die in Parkinson's disease is not known, though research over the last few decades has gone a long way towards solving the mystery, as we'll see in Part 3. Uncovering the reasons for their death is the first step in learning how to stop these neurons from dying, leading to better treatments and hopefully even a cure.

Stay tuned for Part 2: Current Treatments and Part 3: Towards a Cure. Coming soon! 

2 comments:

  1. My Parkinsons disease symptoms started at the age of 54. My fingers on my left hand were stiff and were difficult to move. People noticed that my walk was not normal, I was often asked did I hurt. It was difficult getting up from` a chair and getting out of a car. I was diagnosed a year later, all medications my doctor prescribed did more harm than good. In November, 2016 I started on NewLife Herbal Clinic Parkinson disease natural herbal remedy treatment, my parkinsons symptoms including tremors, slowed movement, shaking deteriorated over the first 9 weeks of the PD herbal formula usage, i am now 59 with no trace of Parkinsons or tremors, visit the clinic website www. newlifeherbalclinic. com or email info@ newlifeherbalclinic. com. The PD herbal formula helped me in a way i just didn’t imagine, this is a breakthrough for all parkinsons disease patients.



    George Herrmann
    Winnipeg, Manitoba, Canada

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  2. Around age 60 I noticed that my handwriting was getting smaller and I was writing faster. I also noticed a small tremor in my right hand. The doctor went over my different symptoms and he suspected I'd either had a small stroke or the beginnings of Parkinson 's disease. After finding a neurologist and some testing I was diagnosed with the beginning stages of Parkinson’s disease. That was 4 years ago. I take Sinimet four times a day to control my symptoms, which include falling, imbalance, gait problems, swallowing difficulties, and slurring of speech,December 2017 our family doctor started me on Mbeki Herbal Clinic Parkinson’s Disease Herbal mixture, 5 weeks into treatment I improved dramatically. At the end of the full treatment course, the disease is totally under control. No case of dementia, hallucination, weakness, muscle pain or tremors.

    Visit Mbeki Herbal Clinic official website w ww.mbekiherbalclinic .com. I am strong again and able to go about daily activities.‌ This Herbal Formula is Incredible!!

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