Protective Effects of Statins against Alzheimer Disease

Alzheimer disease (AD) is a common neurodegenerative disorder, characterized by memory impairment, dementia, and diminished cognitive function. This disease affects more than 20 million people worldwide. Amyloid beta (A beta) plaques and neurofibrillary tangles (NFTs) are important pathological markers of AD. Multiple studies have indicated a potential association between elevated cholesterol levels and increased risk of AD, suggesting that lowering the cholesterol level could be a viable strategy for AD treatment or prevention. Statins, potent inhibitors of cholesterol synthesis, are widely used in clinical practice to decrease the plasma levels of LDL cholesterol in patients with hyperlipidemia. Statins are known to play a neuroprotective role in limiting A beta pathology through cholesterol-lowering therapies. In addition to A beta plaques and neurofibrillary tangles, the brains of AD patients exhibit signs of oxidative stress, neuroinflammatory responses, and synaptic disruption. Consequently, compounds with antioxidant, anti-inflammatory, and/or neuroprotective properties could be beneficial components of AD treatment strategies. In addition to lowering LDL cholesterol, statins have demonstrated therapeutic efficacy in various forms, including antioxidant, anti-inflammatory, and neuroprotective effects. These properties of statins are potential mechanisms underlying their beneficial effects in treating neurodegenerative diseases. Therefore, this review was conducted to provide an overview of the protective effects of statins against AD.