Topical Application of Frankincense Oil Extract Potently Ameliorates Psoriasis-like Dermatitis in Mice via Anti-Inflammatory and Skin Barrier-Protective Effects

Frankincense, a traditional Chinese medicinal resin with well-documented skin barrier-protective and anti-inflammatory properties, has elusive underlying mechanisms in psoriasis-like dermatitis. This study aimed to elucidate its therapeutic potential and molecular targets by investigating frankincense oil extract (FOE) and three key constituents (linalool, α-pinene and 1-octanol) in a classic imiquimod-induced murine psoriasis model, with clinical first-line topical drugs (calcipotriol, tapinarof and dithranol) used as positive controls. Phenotypically, FOE and its constituents significantly ameliorated core psoriasis symptoms (desquamation, erythema, epidermal thickening and splenomegaly) at an efficacy comparable to that of positive controls. FOE suppressed epidermal hyperproliferation and dermal inflammatory infiltration, attenuated the abnormally elevated epidermal expression of TRPV3, β-catenin and COX-2, and increased the expression of the barrier protein K10. Taken together, these findings suggest that FOE restores impaired epidermal barrier function by regulating TRPV3, β-catenin, COX-2 and K10 expression, providing a novel mechanistic basis for the clinical application of traditional frankincense in psoriasis and identifying promising targets for antipsoriatic-drug development.