Insect larvae oil: a high value excipient for lipid-based nanocarriers to tackle atopic dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin disorder with a complex pathogenesis involving epidermal barrier dysfunction and aberrant lipid composition, particularly ceramides and fatty acids (FA). Conventional management options, such as topical glucocorticoids (GC), often lead to adverse effects upon prolonged usage, necessitating the exploration of alternative therapeutic strategies. This study investigated the potential of utilizing novel nanotechnology-based formulations to enhance the topical management of AD. Specifically, we explored the use of solid lipid nanoparticles (SLN) formulated with insect larvae oil as a carrier for dexamethasone (DEX), a representative GC, and as an adjunctive emollient to support skin barrier repair. The lipidic fraction of Black Soldier Fly larvae biomass, holding a rich blend of FA, holds substantial potential as a novel ingredient to tackle skin barrier impairment. Through systematic optimization using Box-Behnken Design, insect larvae oil-based SLN demonstrated favorable physicochemical properties for topical application and satisfactory stability over 2 months. Notably, these SLN exhibited a favorable drug release kinetics, delivering the total DEX payload within a therapeutically relevant timeframe. Furthermore, these SLN showed ability to permeate human keratinocytes without pronounced toxicity, suggesting their potential utility in enhancing drug delivery and cellular uptake. Overall, our findings suggest that insect larvae oil is a promising natural and sustainable ingredient for the development of nanotechnology-driven approaches to AD management, offering a potential avenue for addressing the unmet needs in this challenging dermatologic condition.