Monoterpenes and Diterpenes in Combating Alzheimer Disease, Mechanisms, and Clinical Insights: A Comprehensive Review

Alzheimer disease (AD), as the leading cause of dementia and cognitive decline, requires innovative drug solutions addressing its multifaceted nature. To combat this complex disease, researchers explored various strategies, such as antioxidant mechanisms, promoting non-amyloidogenic pathways in amyloid precursor protein (APP) processing, inhibiting amyloid beta formation and polymerization, metal chelation, and cholinesterase inhibition. These diverse approaches aim to enhance AD’s neuro-protecting, cognitive-enhancing, and mood-modulating potential. Traditional medicine and pharmacy use plant secondary metabolites to mitigate AD side effects. Monoterpenes and diterpenes, characterized by their low molecular weight, exhibit valuable biological properties and clinical applications. Recent research has focused on their anti-AD properties. This study comprehensively reviews monoterpenes’ and diterpenes’ potential effects and mechanisms in addressing AD pathology. Additionally, clinical studies in this field are scrutinized, shedding light on the promising role of these secondary metabolites in managing AD.