Royal Jelly-Loaded LDH Nanostructures: A Novel Topical Therapy for Atopic Dermatitis via Inflammasome Suppression in Mice

Abstract

Purpose: Atopic dermatitis (AD) is a chronic autoimmune disease of the skin, resulting from immune dysregulation and inflammasome activation. This study aimed to develop and evaluate a topical formulation of layered double hydroxide (LDH) nanostructures loaded with royal jelly (RJ) for its therapeutic effects on AD in a mouse model. Methods: LDH nanostructures were synthesized, and characterized by nanoparticle specific tests. The RJ-loaded nanostructures were incorporated into a carbomer-based gel, and sustained release of RJ was measured using a Franz diffusion cell. AD was induced in female BALB/c mice using 2, 4-dinitrochlorobenzene (DNCB)-induced AD. The mice were then divided into six groups: control, Free-RJ (100 mg/kg), Free-LDH, and RJ-loaded LDH at different doses (50, 100, and 200 mg/kg). Results: Treatment with RJ-loaded LDH nanostructures significantly diminished the expression of inflammasome-related genes (NLRP3, Caspase-1, IL-1β, and IL-18) in spleen cells in a dose-dependent manner. Serum levels of IL-1β, IL-18, and IgE were also significantly decreased, and histopathological analysis revealed reduced epidermal thickening and inflammation in the treated groups. Conclusion: These findings suggest that RJ-loaded LDH nanostructures enhance RJ's anti-inflammatory and immunomodulatory effects, offering a promising topical therapeutic strategy for AD management.

Keywords: Atopic dermatitis, Royal jelly, Layered double hydroxide nanostructures, Anti-inflammatory, Topical delivery