Polydopamine nanoparticle-mediated mild photothermal therapy for inhibiting atherosclerotic plaque progression by regulating lipid metabolism of foam cells

Since apoptosis of foam, cells can induce plaque instability, reducing intracellular lipid content while protecting foam cells from apoptosis is beneficial for the safe and efficient therapy of atherosclerosis. In this study, osteopontin-coupled polydopamine (PDA-OPN) nanoparticles were synthesized and applied to target mild photothermal therapy (PTT) of atherosclerosis. The results from laser confocal microscopy indicate that PDA-OPN nanoparticles can be specially recognized and absorbed by foam cells. Under near-infrared laser irradiation, the mild photothermal generated by PDA-OPN decreases intracellular lipid accumulation but does not induce cell apoptosis. In vivo treatments demonstrate that mild PTT can substantially reduce plaque area and improve plaque stability by upregulating the expression of plaque fibrosis in ApoE^-/- mice. Our findings reinforce that the PDA-OPN nanoparticle-mediated mild PTT can inhibit atherosclerotic progression, which provides new insights for developing safe and effective treatment methods for atherosclerosis.