You aren't supposed to understand it. I'm aiming it at folks who actually have budgets and labs in hopes of shaking loose the darned dopamine fixation that has trapped PD research forso many years. This is the core of what Anne Frobert and I were working on. There's a lot more that I will be putting up from time to time, but this is the heart of it as I see it.
The nutshell version is that the bacterial toxin LPS sometimes gets past the fetal defense system at a bad time. This affects the immune and stress systems of the grown up in a way that creates a self-sustaining loop that eventually damages the brain and exhausts the endocrine system (sort of an adrenal fatigue) as well as interfering with neurofunction.
The immune component should respond to the right anti-inflammatory mix. The endocrine or stress component may be tougher. That is why someone with a real lab needs to look at this approach. It isn't original with me nor Anne. The bits and pieces have been in the literature for a long time. It's just that when something is spread across three or four disciplines, things get overlooked. I may be spitting in the wind, but it wouldn't be the first time.