Promoting Tracheal Fistula Healing by Using Designed Bioactive materials

Managing respiratory tract fistulas remains a formidable challenge. To address this, leveraging bio-nanomaterials in animal model systems offers a pathway toward understanding and enhancing fistula management. For example, we have developed nanozymes termed SHA-PtNPs, combining sodium hyaluronate's inherent bioactivities with platinum nanoparticles' enzyme-like properties, aiming to treat tracheal fistulas. Our findings indicate that the SHA layer effectively coats the Pt surface, conferring excellent properties such as improved dispersibility, small particle size (3.7 nm), stability, biocompatibility, and hemostasis. Notably, SHA-Pt nanozymes exhibit heightened catalase-like and superoxide dismutase-like activities compared to SHA alone, showcasing superior reactive oxide species scavenging and anti-inflammatory capabilities. Extensive in vitro analyses confirm these properties, demonstrating safe cell viability, proliferation, and blood compatibility within defined concentration ranges of SHA-PtNPs. Moving to in vivo studies using rabbit tracheal fistula models, the administration of SHA-PtNPs leads to significantly accelerated closure and improved quality of healed fistulas. This improvement is characterized by reduced inflammation, well-organized collagen fiber alignment, reepithelization, angiogenesis, and regeneration. This research marks a pivotal step in vivo, harnessing the synergistic potential of naturally sourced polysaccharides and nanozymes, offering a promising avenue toward respiratory tract fistula management.