A microthrombus-driven fixed-point cleaved nanosystem for preventing post-thrombolysis recurrence via inhibiting ferroptosis

Thrombus-induced cardiovascular diseases threaten human health. Current treatment strategies often rely on urokinase plasminogen activator (uPA) for its efficacy, yet it has such limiting factors as short half-life, lack of thrombus targeting, and systemic side effects leading to unintended bleeding. In addition, thrombolytic interventions can trigger inflammation-induced damage at thrombus sites, which affects endothelial function. To address these challenges, Fer-1/uPA@pep-CREKA-Lipo (Fu@pep-CLipo) has been developed. This system achieves precise and efficient thrombolysis while enhancing the thrombus microenvironment and mitigating ischemia-reperfusion injury, with exceptional thrombus targeting ability via the strong affinity of the Cys-ArgGlu-Lys-Ala (CREKA) peptide for fibrin. The Cys-Nle-TPRSFL-DSPE (pep) could respond to the thrombus microenvironment and fixed-point cleavage. The uPA component linked to the liposome surface is strategically cleaved upon exposure to abundant thrombin at thrombus sites. Importantly, the inclusion of Fer-1 within Fu@pep-CLipo contributes to reactive oxygen species (ROS) scavenging and significantly improves the thrombus microenvironment. This innovative approach not only achieves highly efficient and precise thrombolysis but also positively influences the expression of eNOS protein while suppressing inflammatory factors like TNF-alpha and IL-6. This dual action contributes to improved thrombus inflammatory microenvironment and mitigated ischemiareperfusion injury.