We are flooding GregD's thread with the BBB posts so I thought I would open a separate thread, so as not to hijack his. All are welcome to put as much information as we can find on the link between BBB porosity and PD and other neurological diseases.
In GregD's thread, I gave evidence that Parkies all show disruption of the BBB, (Prof Leenders in Holland) and that a process or treatment like stress increases the porosity of the BBB and makes symptoms worse, whilst a tightening of the BBB with for example curcumin, improves symptoms.

One report I found states, "Alzheimer’s disease may be due to a breakdown in the blood brain barrier."

http://en.wikipedia.org/wiki/Blood-brain_barrier
Alzheimers Disease
New evidence indicates that disrupton of the blood brain barrier in AD patients allows beta amyloid containing blood plasma to enter the brain where the A beta adheres perferentially to the surface of astrocytes. These findings have led to hypothesize that (1) breakdown of the blood-brain barrier allows access of neuron-binding autoantibodies and soluble exogenous Aβ42 to brain neurons and (2) binding of these autoantibodies to neurons triggers and/or facilitates the internalization and accumulation of cell surface-bound Aβ42 in vulnerable neurons through their natural tendency to clear surface-bound autoantibodies via endocytosis. Eventually the astrocyte is overwhelmed, dies, ruptures, and disintegrates, leaving behind the insoluble Aβ42 plaque. Thus Alzheimer’s disease may be due to a breakdown in the blood brain barrier. [4]
Another report cites damage to the BBB is the cause of MS.
http://en.wikipedia.org/wiki/Blood-brain_barrier
"stabilization of the blood-brain barrier integrity
Some diseases, such as MS, begin with the BBB breakdown"

In the report below,it suggests that
" Wouldn't repairing the blood-brain barrier help to "cure" MS?
http://serendip.brynmawr.edu/bb/neur...3/Johnson.html


" Earlier studies have revealed the relative permeability of the molecule (MTPT), through the blood-brain barrier and its ability to induce Parkinson-like symptoms in rats."
http://209.85.165.104/search?q=cache...k&ct=clnk&cd=3


So what determines who gets Alzheimers, who gets MS and who gets PD? Is one section damaged which gives PD whilst another gives AZ? Does a damaged section of the BBB admit a compound which causes MS, whilst another damaged section causes PD by admiting a different toxin.
Is it related to time scale in how long the BBB has been "leaky", ie a very long history of low porosity leakage,l letting in small molecule toxins may give PD, whilst a short term major damage may open the floodgates and admit larger molecules which can cause AZ. It matters whether the compound has an electrical charge, and the size of the molecule.

There does seem to be a strong link between the BBB permeability and neurological disease. Can we find other evidence on what effect a compound or treatment has on the porosity of the BBB, and what is it's effect on PD.
The final goal will be to find a treatment which closes the BBB long term and effectively cures PD. Lets start searching.
Ron