Aging is treated as a vital factor in the etiology of human disease (ES-2014-aging). It is also an important risk factor for AD and PD onset and progression. Biologically, aging is an inevitable biological process that is characterized by a progressive decline in physiological function, including cognition, and by the increased susceptibility to disease (RX-2013). Oxidative stress and mitochondrial malfunction are two interdependent mechanisms that play a central role in brain aging (RX-2013).
Oxidative stress in the aging brain
The brain is particularly vulnerable to oxidative damage as a consequence of its high levels of polyunsaturated fatty acids, high oxygen consumption, high content in transition metals, and poor antioxidant defenses. It has been reported that the aging brain is associated with the accumulation of markers of proteins, lipids, and DNA oxidative damage. It was shown that the aged brain is characterized by increased levels of protein carbonyls, 3-nitrotyrosine, thiobarbituric acid reactive substances (TBARS), and diminished content of cardiolipin and protein thiols (RX-2013).
Along with oxidative stress, mitochondrial dysfunction also contributes to the aging brain. The most …show more content…
Along with oxidative stress, mitochondrial dysfunction also contributes to a brain of aging (RX-2013). As producers and targets of ROS, Mitochondria play an important role in aging (Lenaz-2002). Increased oxidative damage to mitochondrial proteins, lipids and DNA happens in an oxidative damage process. Decreased activity of electron transport chain complexes and increased release of ROS also occur in aging (Remmen-2001). The most important functional deficits documented in aged brains are the loss of the mitochondrial membrane potential and mitochondrial oxidative phosphorylation (OXPHOS) capacity, decreased respiration and ATP synthesis, and increased susceptibility to MPTP opening