Treating aerobic vaginitis with the sprayable nanozyme dressing to improve pregnancy outcomes

Aerobic vaginitis (AV) is characterized by an abnormal vaginal microbiome accompanied by increased inflammatory responses, and well-known to be associated with high risk of preterm delivery. Local therapy offers a simple manner for the targeted treatment of AV, and nevertheless, the treatment effect is not satisfactory due to various factors. Herein, we present a novel sprayable nanozyme dressing with high anti-microbial and anti-inflammation capabilities for AV treatment, which is proved to improve pregnancy outcomes. The dressing is constituted of nanoenzyme, gelatin and nano-chitosan gel, which can be conveniently administrated in the form of a dry powder and formulate a dense hydrogel barrier at the site of action. Due to the natural characteristics of nano-chitosan, it can be electrostatically adsorbed on the surface of bacterial biofilm for sterilization, so viscous hydrogels have inherent antibacterial activity. The cerium oxide nanozyme wrapped in this dressing possesses the multiple enzyme-like properties with outstanding free radical scavenging activity and anti-inflammatory effects. It is worth mentioning that this dressing has shown significant therapeutic effects in the practical performances of AV mice. The dressing exhibited the significant anti-microbial effects, suggesting its high activity even in acidic environment. Moreover, the inflammatory responses are alleviated by promoted tissue repair, reduced proinflammatory cytokines and modulation of vaginal microbiome. More importantly, the treated mice displayed the restored reproductive function and the increased pregnancy rate. These results indicated that the present sprayable nanozyme dressing may be an ideal candidate for local therapy of AV as well as other gynecological diseases.