Imagine you're a cell.

Inside your body runs machinery that creates life itself. But as that machinery keeps running, day after day, you begin to get worn out - friction and processes that cause damage (here "free-radicals" - highly destructive little entities generated by biochemical processes, as well as pollutants, UV radiation and other sources) start to create havoc and you begin to lose battle to disease, old age and ultimately death.

In fact your battle would be over much sooner were it not for numerous mechanisms that you and other mammalian cells evolved over millions of years, as protection from injury that can result from your normal functional processes. The foremost among these internal protective systems is "Glutathione antioxidant system."

Glutathione, a small molecule composed of three amino acids - glycine, glutamate and cysteine - acts as your cellular Super-Mop, soaking up "free-radicals" (with help of sulfur-containing portion of cysteine molecule), protecting your cellular membranes and internal organs from cascading destruction they can cause.

Besides being major antioxidant that you produce as protection from "free-radicals," glutathione is also a very important detoxifying agent, enabling you to get rid of undesirable toxins and pollutants. If you were a liver, kidney or lung cell, you would contain high levels of glutathione, as you'd be exposed to greatest levels of toxins.

Glutathione also helps you dispose of many cancer- producing chemicals, heavy metals, drug metabolites etc. that invade pristine recesses of your cellular world. And Mother Nature (the first recycler) also designed you to use glutathione to recycle other well-known antioxidants such as vitamin C and vitamin E, keeping them in their active state.

Parkinson's Disease (PD), a devastating illness, occurs in one of every 100 people over 65.

It is a slowly progressing disease of nervous system that results in progressive destruction of brain cells (neurons) in an area of brain called substantia nigra. Death occurs usually as a result of secondary complications such as infection.

One of mechanisms known to destroy neurons is damage by free radicals or reactive oxygen species - destructive molecules produced by oxidation of neurotransmitter dopamine.

The Role of Dopamine

The cells of substantia nigra use dopamine - a chemical messenger between brain or nerve cells - to communicate with cells in another region of brain called striatum.

When nigral cells are lost, nigral dopamine levels fall, resulting in a decrease in striatal dopamine.

The typical symptoms of PD - motor function deficiencies characterized by muscle rigidity, jerky movements, rhythmic resting tremors - are result of low levels of striatal dopamine.

Most dopaminergic drugs used to treat PD, are aimed at temporarily replenishing or mimicking dopamine. They improve some symptoms, but do not restore normal brain function nor halt brain cell destruction.

Dopaminergic drugs are generally effective at first in reducing many PD symptoms, but over time they lose their effect.

They also cause severe side effects because they overstimulate nerve cells elsewhere in body and cause confusion, hallucinations, nausea and fluctuations in movement of limbs.

The Role of Antioxidants

When dopaminergic neurons are lost in course of Parkinson's disease, metabolism of dopamine is increased - which in turn increases formation of highly neurotoxic hydroxyl radicals.

The most important free radical scavenger in cells of substantia nigra is powerful brain antioxidant, glutathione. Glutathione levels in PD patients are low.

And as we age, levels of glutathione in dopaminergic neurons of substantia nigra decreases. This appears to hasten cell death and advance progression of PD.

At least 80 percent of substantia nigra cells are lost before symptoms of Parkinson's disease become apparent. This is why it becomes essential to protect or maintain these cells under oxidative stress.

How does Glutathione help in Parkinson's Disease?

Several factors explain why glutathione is so beneficial in Parkinson’s disease.

1. Glutathione increases sensitivity of brain to dopamine. So although glutathione doesn't raise dopamine levels, it allows dopamine in brain to be more effective.