Reactive oxygen species (ROS)-responsive size-reducible nanoassemblies for deeper atherosclerotic plaque penetration and enhanced macrophage-targeted drug delivery

Nanoparticle-based therapeutics represent potential strategies for treating atherosclerosis; however, the complex plaque microenvironment poses a barrier for nanoparticles to target the dysfunctional cells. Here, we report reactive oxygen species (ROS)-responsive and size-reducible nanoassemblies, formed by multivalent host-guest interactions between beta-cyclodextrins (beta-CD)-anchored discoidal recombinant high-density lipoprotein (NPST3) and hyaluronic acid-ferrocene (HA-Fc) conjugates. The HA-Fc/NPST3 nanoassemblies have extended blood circulation time, specifically accumulate in atherosclerotic plaque mediated by the HA receptors CD44 highly expressed in injured endothelium, rapidly disassemble in response to excess ROS in the intimal and release smaller NPST3, allowing for further plaque penetration, macrophage-targeted cholesterol efflux and drug delivery. In vivo pharmacodynamicses in atherosclerotic mice shows that HA-Fc/NPST3 reduces plaque size by 53%, plaque lipid deposition by 63%, plaque macrophage content by 62% and local inflammatory factor level by 64% compared to the saline group. Meanwhile, HA-Fc/NPST3 alleviates systemic inflammation characterized by reduced serum inflammatory factor levels. Collectively, HA-Fc/NPST3 nanoassemblies with ROS-responsive and size-reducible properties exhibit a deeper penetration in atherosclerotic plaque and enhanced macrophage targeting ability, thus exerting effective cholesterol efflux and drug delivery for atherosclerosis therapy.

Automated summary

Nanoparticle-based therapeutics show potential for treating atherosclerosis, but the complex plaque microenvironment hinders their targeting ability. In this study, we developed reactive oxygen species (ROS)-responsive and size-reducible nanoassemblies to overcome this barrier. These nanoassemblies specifically accumulated in atherosclerotic plaque, rapidly disassembled in response to excess ROS, and released smaller nanoparticles for deeper penetration and targeted drug delivery. In vivo studies demonstrated that the nanoassemblies reduced plaque size, lipid deposition, macrophage content, and local inflammatory factor levels, while also alleviating systemic inflammation. Overall, the ROS-responsive and size-reducible nanoassemblies exhibit enhanced targeting ability and provide an effective approach for atherosclerosis therapy.