On the subjecct of oxidation causing neurodegeneration, somehow the results of the study i have pasted in below didn't make the headlines.
As I understand it, peroxynitrite begets nitrotyrosine via the process of oxidation. nitrotyrosine is neurotoxic. And basically, this April 2006 study found that the concentration of 3-nitrotyrosine in the cerebrospinal fluid of PWP treated with L-dopa was significantly higher than that of both healthy folk AND PWP not treated with L-dopa.
Eur J Neurol. 2006 Apr;13(4):346-50.
Cabergoline scavenges peroxynitrite enhanced by L-DOPA therapy in patients with Parkinson's disease.
Isobe C, Abe T, Kikuchi T, Murata T, Sato C, Terayama Y.
Department of Neurology, Iwate Medical University, Morioka, Iwate, Japan. [log in to unmask]
Long-term or high-dose L-DOPA therapy in patients with Parkinson's disease (PD) may accelerate degeneration of dopaminergic neurons, possibly by increasing oxidative stress. To investigate the effects of cabergoline on peroxynitrite-mediated oxidative damage caused by L-DOPA, the concentration of 3-nitrotyrosine in cerebrospinal fluid (CSF) of 18 PD patients was compared with that in 20 normal controls. The concentration of 3-nitrotyrosine in patients following L-DOPA therapy was significantly higher than in untreated PD patients and controls. On the other hand, the concentration in PD patients after cabergoline therapy was significantly lower than in PD patients after L-DOPA therapy alone. These data suggest that cabergoline scavenges peroxynitrite induced by L-DOPA in patients with PD.
PMID: 16643311 [PubMed - indexed for MEDLINE]
"M.Schild" <[log in to unmask]> wrote: Parkinson's and Alzheimer's research makes important progress
Wednesday, 28 Jun 2006 17:40
Parkinson's and Alzheimer's research makes important progress Parkinson's
and Alzheimer's research makes important progress
Scientists in the US have praised new research which has paved the way for
greater insights into the earliest stages of neurodegenerative diseases.
The brain disorders, which include Parkinson's, Alzheimer's and Lou Gehrig's
disease, have been linked to oxidative stress, cell damage caused during
metabolism when oxygen in the body assumes more chemically reactive forms.
Although scientists have not previously identified the precise connection
between oxidation and neurodegenerative diseases, researchers from the US
department of energy's Pacific Northwest National Laboratory and UCLA's David
Geffen school of medicine have found that damage is due to a byproduct of
oxidisation called nitration.
According to the research, many neurodegenerative diseases leave a biomarker,
or 'calling card', known as nitrotyrosine, which is made in the presence of
an oxidative molecule called peroxynitrate.
"Our study certainly suggests that the sensitivity of certain proteins to
peroxynitrite is an early contributor to neurodegeneration, but other factors
may also be involved," said Diana Bigelow, one of the study's authors.
The findings could be significant in that the biomarker could be used to
predict the earliest stages of brain impairment. Some scientists are hopeful
that if byproducts of disease are detected before symptoms occur then as-yet
incurable diseases could potentially be reversed.
Researchers will now explicitly study tissues with neurodegenerative disease
to test the findings.
http://www.inthenews.co.uk/news/news/science/parkinsons-and-alzheimers-research-makes-important-progress-$443550.htm
----------------------------------------------------------------------
To sign-off Parkinsn send a message to: mailto:[log in to unmask]
In the body of the message put: signoff parkinsn
---------------------------------
Do you Yahoo!?
----------------------------------------------------------------------
To sign-off Parkinsn send a message to: mailto:[log in to unmask]
In the body of the message put: signoff parkinsn
Everyone is raving about the all-new Yahoo! Mail Beta.
