A Novel Injectable Selenium-Containing Hydrogel with Antioxidant, Antibacterial, and Anti-Inflammatory Properties for Topical Treatment of Allergic Rhinitis

Allergic rhinitis (AR) is a prevalent inflammatory condition with complex pathophysiology and limited treatment options. Given the current lack of drugs with significant therapeutic effects, it is necessary to develop a hydrogel that can effectively control the nasal inflammation in AR. An injectable and self-healing disulfide bond hydrogel was prepared by cross-linking L-selenocysteine (L-CySe) with carboxymethyl cellulose (CMC). The microstructure, porosity, swelling property, degradability, rheology and mechanical properties of the L-CySe/CMC (SeC) hydrogel were characterized. The antioxidant and antimicrobial activities were evaluated in vitro . The air-liquid interface (ALI) of human nasal epithelial cells stimulated by IL-4. The murine AR model was created by using ovalbumin (OVA). The histopathology of mice and ALI model was analyzed by hematoxylin and eosin (H&E) staining, PAS and Sirius red staining for eosinophils. The levels of OVA-specific IgE (OVA-sIgE) and type 2 cytokines were detected by using ELISA. The biosafety of SeC hydrogel was confirmed by hemolysis, Cell Counting 8 Kit (CCK-8 kit), Live/Dead staining and histopathological examination. SeC hydrogel features a uniform porous structure (porosity of 60.26%), an appropriate swelling/degradation curve, excellent mechanical strength (compressive modulus of 24.74 kPa), and rapid self-healing ability. In both models, it demonstrated a powerful free radical scavenging capacity (>66%), broad-spectrum antibacterial activity (>97% inhibition), and significant anti-inflammatory effects. Hydrogels have good blood compatibility (hemolysis rate <5%) and no cell and organ toxicity. In ALI stimulated by IL-4, it reduced epithelial thickness and inhibits goblet cell proliferation. In AR mice, it alleviated nasal symptoms, reduced epithelial thickening, eosinophil infiltration, goblet cell proliferation, and decreased the levels of OVA-sIgE and type 2 cytokines (IL-4, IL-5, IL-13). SeC hydrogel provides an effective and promising treatment strategy for the effective treatment of allergic rhinitis by taking advantage of its synergistic antioxidant, antibacterial and anti-inflammatory properties. • A novel injectable selenium-containing hydrogel is developed for allergic rhinitis treatment. • The selenium-containing hydrogel exhibits excellent self-healing, injectability, and biodegradability. • It demonstrates potent antioxidant and broad-spectrum antibacterial activities. • It shows good biocompatibility and biosafety in both in vitro and in vivo studies. • The hydrogel alleviates allergic symptoms and inflammation in an allergic rhinitis mouse model.