Identification of the miR-210-3p-EFNA3-YAP axis and its targeted modulation via biomimetic supramolecular nanoparticles to promote ischemic flap survival.

Ischemic skin flaps are highly susceptible to distal necrosis because of insufficient perfusion, oxidative stress, and dysregulated cell death. Here, we investigated the role of Hippo/YAP signaling in ischemic flap survival and identified its upstream regulatory mechanism. Hippo pathway inactivation, characterized by reduced MST1/2 and LATS1/2 phosphorylation and enhanced YAP nuclear localization, was preferentially associated with viable flap regions. Mechanistically, ischemia-induced HIF-1α upregulated miR-210-3p, which suppressed ephrin-A3 (EFNA3), weakened the EFNA3-YAP interaction, and promoted YAP nuclear translocation. Re-expression of EFNA3 partially reversed miR-210-3p-induced YAP activation and cytoprotection, confirming its functional involvement. Mechanistically, ischemia-induced HIF-1α increased miR-210-3p expression, which suppressed EFNA3 and facilitated YAP nuclear localization. EFNA3 re-expression partially reversed miR-210-3p-induced YAP activation, supporting its functional involvement. MiR-210-3p treatment was further associated with reduced oxidative injury, lipid peroxidation, mitochondrial dysfunction, and ferroptosis-related molecular alterations, together with improved perfusion and flap survival. In vivo, miR-210-3p improved local perfusion and flap survival. We further developed a virus-inspired biomimetic nanoparticle for miR-210-3p delivery, which achieved protective effects comparable to AAV-mediated delivery in vitro and in vivo. These findings identify the miR-210-3p-EFNA3-YAP axis as an important regulator of ischemic tissue adaptation and provide a non-viral miRNA delivery strategy for ischemic flap repair.