Photothermal and Photodynamic Therapies via NIR-Activated Nanoagents in Combating Alzheimer’s Disease

It is well established that the polymerization of amyloid-β peptides into fibrils/plaques is a critical step during the development of Alzheimer's disease (AD). Phototherapy, which includes photodynamic therapy and photothermal therapy, is a highly attractive strategy in AD treatment due to its merits of operational flexibility, noninvasiveness, and high spatiotemporal resolution. Distinct from traditional chemotherapies or immunotherapies, phototherapies capitalize on the interaction between photosensitizers or photothermal transduction agents and light to trigger photochemical reactions to generate either reactive oxygen species or heat effects to modulate Aβ aggregation, ultimately restoring nerve damage and ameliorating memory deficits. In this Review, we provide an overview of the recent advances in the development of near-infrared-activated nanoagents for AD phototherapies and discuss the potential challenges of and perspectives on this emerging field with a special focus on how to improve the efficiency and utility of such treatment. We hope that this Review will spur preclinical research and the clinical translation of AD treatment through phototherapy.