Oxidative stress and apoptosis in neurodegeneration.

The pathogenesis of neurodegenerative diseases such as Parkinson's diseases, amyotrophic lateral sclerosis and Alzheimer's disease is unknown. These diseases are characterized by a slow, progressive loss of particular subsets of neurons. Much evidence has accumulated which supports the hypothesis that oxidative stress and damage by free radicals may play an important part in these diseases. In particular recent studies with the inherited form of amyotrophic lateral sclerosis have revealed mutations in the superoxide dismutase gene, which is one of the cell's main defence mechanisms against oxidative stress. These findings suggest a direct link between oxidative stress and the development of a neurodegenerative disease.