Published this morning in the Proceedings of the National Academy of Sciences and entitled "Chronic stress, glucocorticoid receptor resistance, inflammation, and disease risk", and edited by Bruce S. McEwen of Rockefeller University (a true heavyweight in the field). All the pieces suddenly fit and PD is shown to be a result of chronic stress acting on the immune system to damage and disrupt the nervous and GI systems.
It will take years to sort it all out, but the main point from a PWP view is that, as many suspected, it is inflammation that we must counter.
The one dollar explanation-
1) We are exposed to an immune challenge as a fetus, child, or young adult that "primes" or sensitizes our most primitive immune defenders. As a result of this, our immune system reacts at the least provocation and ignores orders to shut down. Over a dozen chemicals are produced that are intended to defend us for short periods but which instead harm us over long periods. We go through life with a slow fire burning in our head.
2) Once ignited, this fire can flame up if it encounters certain "fuels". Most of us have heard of PWP who had the flu in the months leading up to diagnosis. The challenge to the immune system turned up the fire. Other fuels that you may have heard of include stress, herbicides, pesticides, mercury, manganese, and other familiar names. Once the system is primed and the fire started, it is easy to keep the flame going.
3) This fire is a chemical blaze of a dozen or more substances - chemokines and more exotic chemicals produced by our own bodies. Designed for short term exposure, when things go chronic they do damage.
4) But it isn't just that damage that we must deal with. Most of the chemicals are themselves neuroactive. They are neurotransmitters and to a certain extent take over our brains? Ever wonder why you want to stay in bed when you have the flu? A part of you that knows that you chance of survival is greatest if you stay put to minimize energy consumption and the odds of meeting a predator. And so you are ordered to do so. Some of our symptoms can improve with anti-inflammatories. It will require that they be "special" so that they can get past the blood brain barrier. Also that they be fat soluble so that they can access as much of the central nervous system as possible.
5) In light of the above, some things make sense that didn't before. So many things looked like causes because there were causes - but only if the system was primed. Stress fans the flames by years of over producing cortisol in a doomed attempt to quench the fire, with the result that our receptors respond less well and more hormone is produced. Very much like insulin and diabetes.
I am encouraged more by this report than I can say - and the darned thing never even mentions PD outright. But it is written right there on the page as plain as day. Take time to educate yourself. Your neuro knows even less than you do and you have to be your own endo. We are not in Kansas anymore and have to think in terms of multiple disciplines. But, damn, things sure look brighter than they did yesterday.