Melatonin can be neuroprotective against Parkinson's disease?

First, here is a link about neuroprotective properties of certain spices. Scroll down to 

Parkinson

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3183139/?tool=pubmed

For brain to optimally produce melatonin at night you need a very dark room (can 

not see your hand in front of face) It appears a sleep mask over eyes does help. 

Some earlier research had seemed to show light anywhere on body was a problem 

but this is in doubt now. Article below from life extension.

Melatonin may protect against Parkinson's disease

The theory that Parkinson's disease has an environmental cause has recently 

gained credence. A study published in the December 2000 issue of the journal 

Nature Neuroscience demonstrated that the pesticide Rotenone caused Parkinson's 

symptoms  when administered to rats. The article indicated that Rotenone may 

cause  the mitochondria, which are the power plants of the cells, to produce  

free radicals, thereby causing the damage that leads to Parkinson's  disease.

In a study published in the  January 1, 2001 issue of the Federation of American 

Societies for  Experimental Biology or FASEB journal, researchers injected the  

neurotoxin 6-hydroxydopamine (6-OHDA) into the right substantia nigra of  the 

brains of rats. This neurotoxin produces a loss of dopaminergic  cells, thereby 

creating an experimental model of Parkinson's in the  right hemisphere of the 

brain of the rats who received the injection, as  Parkinson's disease is 

characterized by a loss of these cells. The rats  exhibited a postural assymetry 

which causes rotation away from the the  undamaged side of the body, seen as 

circling behavior. Rats given  melatonin prior to administration of 6-OHDA did 

not demonstrate this  behavior. Analysis of the affected brain tissue in rats 

receiving 6-OHDA  who were not protected with melatonin showed a loss of complex 

1  activity of mitochondrial phosphorylation enzymes, a reduction of which  has 

been observed in the substantia nigra of Parkinson's disease  patients. However, 

the melatonin-treated rats were protected against  this loss. The researchers 

conclude that a deficit in mitochondrial  complex 1 could cause free 

radical-induced cell death in Parkinson's  disease, both directly and by 

decreased ATP synthesis and energy  failure, and that melatonin may be useful in  the

treatment of  neurodegenerative disorders in which free radicals play a role.