It has been widely reported that intense oxidative stress-related processes in the brain are one of the main causal factors involved in the impairment in cognitive functions through two critical changes in the brain. First, a decrease in neurotransmitters, essential for memory and learning functions, for example, acetylcholine (ACh), as well as a decrease in level of natural antioxidants in the brain by activating microglia, a source of reactive oxygen species (ROS), has been reported. The formation of ROS and other free radicals during metabolism is an important and normal process that is ideally compensated by an elaborate endogenous antioxidant system. However, excessive radical production and their accumulation result in oxidative stress, which has been implicated in mechanisms responsible for oxidative injury of neurons by causing damage of cell structures, including lipids, membranes, and proteins. The central nervous system (CNS) is very susceptible to oxidative stress