In vivo Evaluation of the Antipsoriatic Effect of Alginate Hydrogel with Lavandin Essential Oil and Its Main Components after Topical Application

Abstract

Abstract The essential oils obtained from Lavandula species possess antibacterial, antifungal, anti-inflammatory, and antioxidant activities. In our study, lavandin oil was hydrodestillated from Lavandula × intermedia (Lamiaceae), and new alginate-based hydrogel formulations containing lavandin oil, linalool, and linalyl acetate were prepared for the first time. Using the gas chromatography (GC) and gas chromatography - mass spectrometry (GC-MS) methods fifty eight components of obtained essential oil were identified. Subsequently, the antipsoriatic activity of the created formulations was investigated by applying an imiquimod-induced mouse model. Alginate-based hydrogels were used as carriers for lavandin oil, linalool, and linalyl acetate. Pharmaceutical properties, such as viscosity and adhesiveness, which influence the contact time of the formulation to the skin, were also analysed using a viscometer and texture analyser, respectively. In addition, the histopathological examination of imiquimod-induced psoriasis-like mice ear skin stained with H&E (haematoxylin and eosin) was conducted after applying the examined formulations. Additionally, the impact of lavandin oil, linalool, and linalyl acetate on the expression of CD3 (cluster of differentiation 3), CD68 (monoclonal mouse anti-human), and Ki67 (marker of proliferation Ki-67) were studied. Histopathological studies showed that alginate-based hydrogels with lavandin oil, linalool, and linalyl acetate decreased the mice ears’ oedema and the analysed psoriasis symptoms (parakeratosis epidermal thickening, hypertrophy of the spinous layer, inflammatory infiltrates, Munro's microabscesses, Kogoj's micro-pustules, and dermal papillae oedema). The prepared formulations inhibited proliferation of the cells (Ki67 staining method) and expression of CD3 and CD68. The most potent activity against the inflammation in psoriasis was the preparation containing 5% lavandin oil. The presented results suggest that the topical application of lavandin oil may be efficient against psoriasis due to the inhibition of cell proliferation and reduction in many T-cells, macrophages, and lymphocytes in mice ear skin with inflammation induced by imiquimod.