Emerging role of antioxidants in Alzheimer's disease: Insight into physiological, pathological mechanisms and management

Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by memory loss, cognitive decline, impairment in activities of daily living, and loss of independent function. Cognitive decline and brain shrinkage, particularly hippocampal atrophy, are associated with the accumulation of tau proteins. They cause inflammation, amyloid plaque deposition, neuronal loss, temporofrontal cortex atrophy, aberrant protein fragment clusters, and twisted fiber bundles. Given the significant role of oxidative processes in neurodegeneration, it is logical to consider the potential of antioxidants in the treatment of AD. Several antioxidants, including glutathione, astaxanthin, ascorbyl palmitate, catalase, and molecular hydrogen, play important roles in AD. Antioxidants interact with free radicals to neutralize them. Several studies have suggested that oxidative stress or damage is involved in the development of AD via different mechanisms and pathways. Thus, new approaches are needed to reduce the extent of oxidative damage that may be therapeutically effective against AD. Although certain antioxidants have exhibited notable benefits in animal models, their efficacy in human clinical trials has been limited, casting doubt regarding the efficacy of antioxidant treatments for AD. Therefore, a more focused and precise strategy that incorporates antioxidants is essential for slowing or stopping AD progression. The integrated role of antioxidants in reducing inflammation must be considered, because the link between inflammation and AD is undeniable. Therefore, the present study aimed to elucidate the role of antioxidants in AD, with the goal of aiding researchers in developing effective and potentially enhanced antioxidant-based therapeutic strategies.