Topical Low-Dose Talc Is Associated with Early Histological Changes in Airway Anastomotic Healing: A Pilot Rat Study

Optimal healing of tracheal anastomosis remains a critical determinant of surgical success. While talc is widely used as a sclerosing agent in pleurodesis, its potential influence on airway anastomotic repair has not been investigated. This pilot study aimed to explore whether localized low-dose talc application may modulate early healing responses in a rat tracheal anastomosis model. Six male Sprague–Dawley rats were randomly assigned to control (n=3) or talc-treated (n=3) groups. All animals underwent 50% anterior tracheal incision and end-to-end repair. The treatment group received approximately 10 mg of medical-grade sterile talc applied topically to the anastomotic line. The predefined primary endpoint was a semi-quantitative histological healing score assessing epithelial integrity, inflammatory infiltration, and fibrosis at postoperative day 14. Secondary exploratory analyses included oxidative stress markers (MDA, SOD, GSH), serum cytokines (IL-6, IL-1β, TNF-α), and tracheal PI3K/Akt/mTOR protein levels measured by ELISA. Compared with controls, talc-treated animals demonstrated improved histological healing scores, characterized by better-preserved epithelial architecture and reduced inflammatory infiltration. Collagen deposition appeared more organized and less excessive in the treatment group. Antioxidant markers (SOD and GSH) were increased, while serum pro-inflammatory cytokine levels were reduced. Elevated PI3K/Akt/mTOR protein levels were observed, consistent with activation of regenerative signaling pathways. Given the small sample size, statistical analyses were considered exploratory. In this pilot rat model, localized low-dose talc application was associated with histological and molecular findings consistent with enhanced early tracheal anastomotic healing. These preliminary findings are hypothesis-generating and require validation in larger, adequately powered studies with long-term functional airway assessment before any translational implications can be considered.