Molecular Mechanisms Underlying Alzheimer’s Disease Pathogenesis: Comprehensive Overview

Alzheimer’s disease (AD) is a progressive, multifactorial neurodegenerative disorder ranking first as cause of dementia in the elderly. It is characterized by the progressive deterioration of the central nervous system, leading to impaired cognitive function and reduced ability to perform daily activities. Pathological hallmarks of AD include the accumulation of β-amyloid plaques and neurofibrillary tangles which ultimately cause neuronal death and synaptic loss. The vast majority of AD cases are sporadic, with aging representing the primary non-modifiable risk factor contributing to disease susceptibility and progression. However, several factors encompassing genetic predisposition, systemic inflammation, chronic diseases, infections, traumatic brain injury, lifestyle factors, and environmental exposures may affect AD onset. This work aims to describe and discuss the main molecular pathways involved in AD pathophysiology and to examine how these mechanisms cross-interact in promoting neurodegeneration and disease progression.