My father had it in his 80s, and my nearly 100 year old mother started showing signs of Parkinson’s before she died.
I think the important thing about this animal trial is that they used the only form of the B-3 vitamin that can enter the neurons (nicotinamide riboside - not to be confused with niacin or niacinamide, or just nicotinamide or ribose). I have read encouraging anecdotal stories from people taking NR. NR has been given GRAS status “Generally Regarded as Safe” by the American NIH, and has Letter of No Objection from the USA FDA.
The trial was on laboratory grown cells and flies. That’s a heck of a leap to humans. The problem with vitB3 is that it is water soluble, and any excess in the body passes out in the urine.
It’s well known that B3 deficiency can cause dementia in the condition known as Pellagra, but there’s no evidence that B3 can improve dementia in those who aren’t deficient. It’s actually quite difficult to get B3 deficient eating a normal diet. And as I said earlier, taking extra B3 is fairly futile as it gets flushed down the toilet.
For these reasons, I suspect that although this is interesting, it won’t have a significant effect in treating PD.