Objective To explore the pro-inflammation resolution and protective effects of reactive oxygen species (ROS)-responsive liposomes modified with a cardiac-targeted peptide and loaded with resolvin D1 (RvD1, C-LP-RvD1) on myocardial ischemia-reperfusion (MI/R) injury.

Methods The C-LP-RvD1 nanoliposomes were constructed, characterized physically and chemically, and evaluated for in vitro release. Non-targeting peptide-modified drug-loaded liposomes (LP-RvD1) were served as controls. Apoptotic adult mouse cardiomyocytes (AMCMs) were used to verify in vitro targeted binding capacity of C-LP-RvD1. In MI/R mice models, the in vivo distribution and cardiac enrichment of C-LP-RvD1 were assessed. Levels of specialized pro-resolving mediator (SPM) and inflammatory factors in cardiac tissue homogenates and cell culture supernatants were measured using enzyme-linked immunosorbent assay (ELISA). Cardiac function and fibrosis remodeling were evaluated via echocardiography and Masson staining four weeks after treatment. Biosafety was evaluated in healthy mice injected by C-LP-RvD1.

Results The C-LP-RvD1 exhibited good nanoscale uniformity and stability, with ROS-triggered accelerated release characteristics. In vitro experiments showed that C-LP-RvD1 had higher binding capacity to apoptotic AMCMs than LP-RvD1, with significantly higher SPM levels (P＜0.01) and lower inflammatory factor levels (P＜0.05). In vivo experiments indicated enhanced cardiac enrichment of C-LP-RvD1 in MI/R injured hearts, with higher local myocardial SPM levels and lower inflammatory factor levels compared to LP-RvD1 (P＜0.05). Four weeks after treatment, compared with LP-RvD1, the C-LP-RvD1 mice group showed improved cardiac function indicators and reduced ventricular fibrosis remodeling ratio (P＜0.05). Safety evaluation revealed no significant systemic inflammation, immunogenicity, or coagulation abnormalities in healthy mice, with liver and kidney function and major organ histology showing no notable damage.

Conclusions C-LP-RvD1 improves effective delivery of RvD1 to MI/R injured hearts through injury-targeted enrichment and ROS-responsive release, promoting inflammation resolution and suppressing excessive inflammation, thereby improving cardiac function and reducing adverse remodeling, with favorable biosafety.