Role of Oxidative Stress in the Onset of Alzheimer’s Disease

Alzheimer's disease (AD) is the most common of the dementia-related neurodegenerative diseases. Brain is one of the most vulnerable organs to oxidative stress as it consumes 20% of the oxygen supplied by the respiratory system in the human body. Neurodegenerative diseases are defined as progressive degeneration, malfunctioning, and death of the neurons. The pathological course of AD can be portrayed as initiation in a certain cell population and propagation to higher order connectivity as the disease progresses. Energy conversion is a fundamental process in living bodies. As a by-product of this energy conversion or electron transport reactions, our bodies produce superoxide anions, hydrogen peroxide, and hydroxyl radical, which are collectively called reactive oxygen species. The oxidative stress from metal-abeta interaction can arise in a number of ways. Metal interaction limits the availability of abeta. Abeta has antioxidant activity at low concentration, and with the sequestration of abeta in plaques, antioxidant defense system in AD brain is disturbed.