A Peritoneum-Inspired Biomimetic Asymmetric Patch for Functional Repair and Anti-Adhesion in Abdominal Wall Defects

Poor repair outcomes of abdominal wall soft tissue defects often lead to hernia recurrence and tissue adhesion, thereby increasing the medical burden. An ideal repair material should simultaneously fulfill the requirements of anti-adhesion properties, wet tissue adhesion capability, biodegradability, and the ability to promote functional tissue regeneration. Herein, inspired by the natural abdominal wall architecture, we designed a biomimetic Janus-structured repair patch, denoted as PS-PDH. This patch integrates a biodegradable poly(4-hydroxybutyrate) (P4HB) electrospun fibrous membrane with a glutathione-responsive degradable poly(sulfobetaine methacrylate) (PSBMA) hydrogel via polydopamine (PDA). It exhibits excellent asymmetric adhesive properties: the fibrous side facilitates cell adhesion and proliferation, while the hydrogel side effectively resists cell and protein adhesion. Furthermore, PS-PDH possesses robust mechanical properties, enabling it to adapt to dynamic tissue deformation. Notably, the patch effectively scavenges free radicals and intracellular reactive oxygen species (ROS), while promoting macrophage polarization from the pro-inflammatory M1 to the pro-regenerative M2 phenotype. In a mouse full-thickness abdominal wall defect model, PS-PDH effectively prevented postoperative adhesion and fibrosis, modulated the inflammatory microenvironment, and promoted functional muscle and vascular regeneration. Therefore, this biomimetic Janus-structured patch offers a reliable and highly clinically translatable strategy for the functional repair of abdominal wall soft tissue defects.