Plasma-activated hydrogel promotes postoperative colonic anastomotic leak healing

• Hyd@CAP demonstrates considerable potential for the prevention of anastomotic leak following gastrointestinal surgery. • Hyd@CAP exhibits excellent absorption capacity and surface adhesion properties. • Hyd@CAP exerts anti-inflammatory, antibacterial and pro-healing effects through the release of reactive oxygen and nitrogen species. • Inhibition of the mTOR signaling pathway is associated with prolonged healing time of postoperative anastomotic leak. • ROS/RNS further contribute to tissue repair by activating the mTOR signaling pathway. Colonic anastomotic leak (CAL) represents one of the most critical complications following gastrointestinal surgery, inducing severe intra-abdominal infections, adhesion formation and persistently high mortality rates. This complication imposes a substantial socioeconomic and healthcare burden. To address this challenge, cold atmospheric plasma (CAP)-loaded hydrogel was developed for intraperitoneal delivery of reactive species to anastomotic sites. An anastomotic leak (AL) model was established in SD rats via surgical intervention. For in vitro studies, apoptosis was induced in HCT116 cells by treatment with TNF-α. Apoptosis was assessed using flow cytometry and Western blotting. Inflammatory cytokine levels were measured by enzyme-linked immunosorbent assay (ELISA). Histological changes were evaluated via immunofluorescence staining and immunohistochemistry. The cold atmospheric plasma-activated hydrogel (Hyd@CAP) gradually formed effective coverage over the anastomotic sites, enabling sustained release reactive oxygen and nitrogen species (RONS). These reactive species collectively exerted multifunctional effects including antimicrobial, anti-inflammatory and tissue-reparative activities. Our research demonstrated consistent adhesive stability at anastomotic sites and significant reduction in adhesion scores. Transcriptomic analysis of anastomotic tissues revealed that Hyd@CAP accelerated regeneration and proliferation of intestinal epithelial cells by releasing RONS that further activated the mTOR signaling pathway, thereby exerting antimicrobial, anti-inflammatory and tissue-reparative effects. Hyd@CAP represents an emerging therapeutic strategy with potential applications in the management of AL following gastrointestinal surgery. Its efficacy has been preliminarily validated in a rat model of CAL, suggesting potential for early-phase clinical translation and possible extension to anastomotic repair throughout the entire gastrointestinal tract.