Crossing the blood–brain barrier: nanoparticle-based strategies for neurodegenerative disease therapy

Neurodegenerative conditions, including Alzheimer's, Parkinson's, amyotrophic lateral sclerosis, and Huntington's disease, represent a critical medical challenge due to their increasing prevalence, severe consequences, and absence of curative treatments. Beyond the need for a deeper understanding of the fundamental mechanisms underlying neurodegeneration, the development of effective treatments is hindered by the blood–brain barrier, which poses a major obstacle to delivering therapeutic agents to the central nervous system. This review provides a comprehensive analysis of the current landscape of nanoparticle-based strategies to overcome the blood–brain barrier and enhance drug delivery for the treatment of neurodegenerative diseases. The nanocarriers reviewed in this work encompass a diverse array of nanoparticles, including polymeric nanoparticles (e.g. micelles and dendrimers), inorganic nanoparticles (e.g. superparamagentic iron oxide nanoparticles, mesoporous silica nanoparticles, gold nanoparticles, selenium and cerium oxide nanoparticles), lipid nanoparticles (e.g. liposomes, solid lipid nanoparticles, nanoemulsions), as well as quantum dots, protein nanoparticles, and hybrid nanocarriers. By examining recent advancements and highlighting future research directions, we aim to shed light on the promising role of nanomedicine in addressing the unmet therapeutic needs of these diseases.