A Multitarget Nanosystem Loaded with Donepezil for Alzheimer's Disease Treatment by Activating Mitophagy and Reshaping the Inflammatory Microenvironment.

A paradigm shift from single-target interventions toward multitarget synergistic actions is increasingly recognized as a promising therapeutic approach for Alzheimer's disease (AD). Given this, an oxidative stress-responsive nanocomposite, RuO2-TPP/Don@BSA (RDB), was developed to enable effective AD therapy via a "cocktail strategy". Utilizing bovine serum albumin (BSA), the system crosses the blood-brain barrier (BBB) through gp60 receptor-mediated endocytosis. Within the AD brain microenvironment, RDB undergoes disulfide bond cleavage in response to elevated H2O2 levels, thereby releasing donepezil (Don) and RuO2-TPP in a stimuli-responsive manner. Meanwhile, RuO2-TPP escapes from lysosomes, targets mitochondria, and interrupts the oxidative stress cascade, further repairing mitochondrial dysfunction and activating mitophagy. Moreover, RDB promotes the polarization of microglia from the pro-inflammatory M1 phenotype to the anti-inflammatory M2 phenotype, thereby reshaping the inflammatory microenvironment of AD. Finally, RDB demonstrated significant efficacy in APP/PS1 transgenic AD mice, markedly reducing hippocampal expression of GFAP and Iba-1, concomitant with a notable improvement in cognitive dysfunction. In summary, these findings establish RDB as a multitarget synergistic therapeutic system that offers a promising strategy for the treatment of AD.