Oxidative stress, aging and the proteasomal system

Oxygen free radicals and other oxidants. al-e causing potential danger for intracellular proteins during the lifetime of cells and organisms. Therefor e, protein oxidation is one of the natural consequences of aerobic life. Th e degradation of non-functional, oxidized proteins is an essential part of the antioxidant defenses of cells. The major proteolytic system responsible for the removal of oxidized cytosolic proteins is the proteasomal system. This system consists of the 20S 'core' proteasome and a multitude of variou s regulators. It is known that certain components of this system are regula ted during oxidative stress and aging. One of the highlights of age-related changes of cellular metabolism is the accumulation of oxidized proteins. T he question whether the accumulation of oxidized proteins during aging is d ue to a malfunction of the intracellular proteolytic machinery of the cell remains still unsolved. The information available about an age-related decl ine of the proteasomal system is very contradictory. The current literature about the proteasomal system, the regulation of this system during oxidati ve stress and the age-related changes are in the focus of this review.