Free Radical Effects -

Free Radicals Parkinsons Disease

Parkinson's disease, or paralysis agitans, is a progressively disabling condition featuring shaking of the hands with 'pill rolling' finger movements, rigidity of muscles, slowness of speech and movements, difficulty in getting started in walking, tottering steps, a mask like face and tiny handwriting. It is due to the degeneration of certain cells in the central part of the brain known as the 'substantial nigra' that produce a substance called 'dopamine', and it is treated with the drug levodopa and other substances that stimulate dopamine receptors in the brain. The substance that stimulate dopamine receptors in the brain. The cause of the changes in the brain cells is unknown, but in the late 1980s it became clear that various oxidative processes involving the formation of free radicals were involved.

A large trail was therefore started in 1987 to see whether vitamin E indorses of 2,000 mg per day could delay the progress of the disease. Eight hundred patients with Parkinson's disease were involved in the trial, which was conducted simultaneously in a large number of different hospitals and research departments in America and Canada. The patients were divided into four groups, one of which received the vitamin E. the trial report was published in 1993 in the New England Journal of Medicine.

Unhappily, the trial showed no evidence of any beneficial effect of vitamin E on the progress of the disease. According to the researchers, this disappointing result might have been due to the fact that adequate amounts of the vitamin were unable to pass the 'blood-brain barrier' to reach the cells of the substantial nigra. It was also suggested that a negative result with vitamin E did not necessarily imply that other antioxidants might also be ineffective. They suggested that trials of these were still warranted. There were no significant adverse effects attributable to the dosage of the vitamin. One of the groups in the trial was treated with another drug, selegiline ( Elderpryl). This group did enjoy worthwhile benefit in terms of slowing of the disease.

Medical research can benefit from its failures as well as its successes. This major study teaches that theoretical ideas about free radicals are not always borne out in practice. The demonstration that free radicals are the cause of a particular kind of cell damage does not necessarily mean that any one particular antioxidant taken by mouth will prevent such damage. The antioxidant has to be appropriate and it has to get to the site of free radical damage.