Nanomedicine and Neurodegeneration: Targeting Alzheimer’s Disease Pathology and Drug Delivery Challenges

Alzheimer’s disease (AD) is a progressive neurological disorder and the leading cause of dementia in older adults, characterized by memory loss, cognitive dysfunction, and behavioural disturbances. The disease is associated with the abnormal buildup of beta-amyloid plaques and hyperphosphorylated tau tangles, along with oxidative stress, mitochondrial impairment, neurotransmitter imbalances, and neuroinflammation. Genetic factors, particularly the presence of the APOE- ε4 allele, further increase disease susceptibility. Despite the availability of FDA-approved drugs targeting cholinergic and glutamatergic systems, current treatments provide only symptomatic relief and do not halt disease progression. One of the major challenges in AD therapy is the limited ability of drugs to cross the blood-brain barrier (BBB). Nanotechnology presents a promising alternative by enabling the targeted delivery of therapeutic agents across the BBB with improved bioavailability and minimal systemic side effects. This review discusses the underlying mechanisms of AD and recent advancements in Nano formulations such as liposomes, polymeric nanoparticles, dendrimers, and lipid-based carriers for delivering anti-amyloid, anti-tau, and antioxidant therapies. These innovative approaches may offer new hope in managing and potentially modifying the course of Alzheimer’s disease.