Lipid and Polymeric Nanoparticles in Neurodegenerative Diseases: Progress and Challenges in Alzheimer’s, Parkinson’s, and Huntington’s Diseases

Neurodegenerative diseases (NDs) such as Alzheimer’s, Parkinson’s, and Huntington’s disease are progressive and currently incurable conditions characterized by the deterioration of neuronal structure and function. Its incidence is increasing, primarily driven by global aging, and it represents a significant public health concern. Traditional therapies offer only symptomatic relief and are unable to halt or reverse the underlying neurodegenerative processes. One of the key challenges in developing effective treatments is the presence of biological barriers, such as the blood–brain barrier (BBB), which limits drug delivery to the central nervous system (CNS), namely the brain. Nanotechnology has emerged as a promising tool to overcome these obstacles. Nanoparticles (NPs), due to their small size, biocompatibility, and versatility, can be engineered to cross the BBB, protect therapeutic agents from degradation, and deliver them precisely to target sites in the brain. This work explores the current advances in lipid and polymeric-based nanoparticle (LNPs and PNPs, respectively) drug delivery systems (DDS) and their application in preclinical studies for the treatment of the NDs previously mentioned. The presented studies suggest that this strategy holds great potential, offering new perspectives and emerging strategies to improve therapeutic outcomes for NDs, and promote neuroprotection of the brain.