Hi Joop,

Are you saying that methylation is the process which is involved in all the processes of degeneration or improvement of symptoms of PD?
I accept that carbidopa has a methyl group and levodopa hasn't, and this could be the reason why carbidopa can't pass a healthy BBB whilst levodopa can. I don't think that has any bearing on the BBB permeability theory however. How do you explain by methylation that whilst levodopa can pass a healthy BBB, dopamine can't. There is no methyl group involved here. The only difference is a molecule of carbon dioxide. The difference between the two compounds is very small, yet one can pass, the other can't.
What I am saying is substances or treatments which widen the permeability of the BBB cause an exacerbation of symptoms, such as stress or carbon monoxide etc. How can you explain it is due to methyl groups in cases such as these. Look at my list of questions and answers and try to give answers for all based on methyl groups.
Joop, you say, " You may conclude that damage of the BBB is the common factor, but that does not convince me yet."
I despair of convincing anyone, particularly the medical profession. How much evidence do people need.
1. Your Dutch professor Leenders has shown that PWP all have defective BBB's.
2. Every substance, or treatment I have examined that widens the permeability of the BBB causes an exacerbation of symptoms. Stress, carbon monoxide, pesticides, organophosphates, old age etc
3. Every substance or treatment that I have examined that reduces the permeability of the BBB causes an improvement in systems. curcumin, alpha lipoic acid, CDP choline, hypertension drugs etc.
4 The BBB is implicated in a number of neurological diseases, eg Alzheimers, MS and Chronic Fatigue Syndrome.
The medical profession could so easily and cheaply test this theory. The BBB permeability (BBBP) of a living person can be measured. So take a healthy person and measure his BBBP. Take a group of PWP with years since diagnosis of 1, 2,5, 8, 10, and 15 years, and measure their BBBP.
If you get a correlation, (the healthy person is lowest BBBP and the 15 year is highest, with the rest in ascending order), it is proven.
Then you also have a scientific method of diagnosing PD, instead of winding his arm around looking for cogwheel rigidity. This is the 21st century isn't it??? Then direct all your research to a way of repairing the BBB. Stop drilling holes in peoples heads!!
This project could surely be completed for below $0.5m. Yet hundreds of millions have been spent, and where are we?
There should be a film made in the "Carry on" series called "Carry on Suffering"!!!!
Joop, I am grateful for your input, and Rick and others, it feels as though I am not alone. At least you are putting thought into the matter, but I wish we could get somewhere. We are all getting older, and our BBBP is getting wider by the day.
Ron