Homocysteine is a link between Parkinson’s disease and depression
 

A study finds out that high levels of homocysteine make a patient with Parkinson’s disease more likely to suffer from depression.
We already know that elevated levels of the amino acid homocysteine are a risk factor for dementia and Alzheimer’s disease. And high levels are also linked to impaired cognition, even if people don’t actually have dementia. Those with Parkinson’s disease are at risk of elevated homocysteine because of the drugs they take.

Researchers at the University of Texas Southwestern Medical Center report on how high homocysteine affects Parkinson’s patients...about one third of a group of 97 patients had elevated levels. These patients were more depressed than those with normal homocysteine and were more likely to have impaired cognition. The higher levels of homocysteine were linked to medication and is something that perhaps should be taken into account when planning treatment.

http://www.tele-management.ca/2013/0...nd-depression/

I FIND that interesting, i experience mental fatigue in the afternoons now, and taking an extra C/L doesn't help at all, but my motor symptoms are managed ok, just mentally feel worse. once that "fatigue" starts it doesn't go away until the next day after i've not taken C/L for 8-10 hrs. might just be a coincidence, might not even be called cognition. need to pursue this a little bit. i assume i'm taking enough b vitamins to minimize homocysteine. but this started after i had to increase my C/L to 800mg/day. seems to be some cause and affect, but of course hard to test, have to take some C/L, if i wait too long in the A.M, to take my first dose get similar mental fatigue.

mutations in methylation pathway genes
 

I wonder how much mutations in MTHFR, MTRR, and other methylation pathway genes are related to this finding. Could simply trying to "fix" these deficiencies (ie taking folate, B12, B6) help?

going that route...
 

Olsen, we are currently trying this route...and have ordered the B complex and probiotic from Dr. Lynch, we have so many of the symptoms of this (although I have to say the symptoms of MTHFR read like a PD handbook!)

Here is his site:

http://mthfr.net

There is a ton of info. on there, and not just about the two main MTHFR mutations 1298 and 677. I personally believe this is all related somehow, as the links just continue to increase...one day we'll tie it all together, I hope.

This is a very common issue, I think I read 40% of the population has it, conservatively, other reports put it as high as 60%.