Introduction to oxidative stress and mitochondrial dysfunction.

Oxidative stress and mitochondrial dysfunction are discussed in this article. Mitochondria are the major producers of free radicals and the major target of oxidative damage. Oxidative stress is simply the elevation of free radicals (reactive oxygen species/reactive nitrogen species) found in cells that accumulate to higher than normal levels. Excessive or inappropriate oxidative stress damages cells and tissues, specifically mitochondria, cell membranes, DNA, proteins, and lipids.