Native PLGA nanoparticles attenuate disease pathology via multiple pathways in 5xFAD Alzheimer's model

<h4>Introduction</h4>Elevated amyloid beta (Aβ) levels and aggregation contribute to neurotoxicity and development of Alzheimer's disease (AD), the leading cause of dementia in the elderly. While we reported that native poly(D,L-lactic-co-glycolic acid) (PLGA) nanoparticles, clinically used in drug delivery, suppress Aβ aggregation/toxicity, their effects in adult 5xFAD mice with advanced Aβ pathology remain unknown.<h4>Methods</h4>We evaluated the effects of native PLGA in 8-month-old male 5xFAD mice via chronic intracerebroventricular (ICV) infusion using mini osmotic pumps. Cognitive function, amyloid level/burden, synaptic integrity, and neurodegenerative events were assessed along with transcript levels in brain tissues using bulk RNA sequencing (RNA-seq).<h4>Results</h4>PLGA treatment reversed cognitive deficits, reduced Aβ levels/deposits, and attenuated neurodegenerative events. These effects were associated with modulation of Aβ production, oxidative stress, and lysosomal Aβ clearance. RNA-seq revealed transcriptional changes related to vesicle trafficking, immune activity, and redox regulation.<h4>Discussion</h4>Native PLGA, by targeting different facets of the Aβ axis, offer unique therapeutic potential in treating AD-related pathology.