Hi, Mr X
I am suspicious of articles like the one you quote, especially when the organisation producing it seems to be in the business in selling dietary supplements!
But please interpret these comments as healthy scepticism rather than cynicism. The topic indeed deserves careful examination:
The article gives a lot of references and some of them are from serious scientific journals. So it does seem that PQQ does have an important role in the body. (It is a big jump, however, to go from the recognition that the compound is important for mitochondrial health and its anti-oxidant properties to proposing that it should be taken to cure diseases Parkinson's.)
It is certainly worth pursuing this further. The article was written more than 4 years ago (2010) and one wonders what has happened since. If researchers thought that it had legs then surely they will have done more work on it and there will be more recent scientific papers in the scientific literature. They would be worth ferreting out.
Do you (or the Parkinson's UK Research Team) have time do a bit more digging around (in PubMed, say) and see what you can find and report back here?