Abstract
BACKGROUND: 'Taikong blue' lavender, a space-bred cultivar of Lavandula angustifolia, is one of the main lavender essential oil production crops in Xinjiang Province, China. Several cases of local usage indicated that 'Taikong blue' lavender essential oil (TLEO) had excellent anti-inflammatory and antioxidant properties for skin problems. However, to date, substantial data on these functions are lacking. In this study, we aimed to investigate the composition and bioactivities of TLEO and the potential underlying mechanisms through LPS-induced inflammatory models of HaCaT and RAW264.7 cells. METHODS: The composition of TLEO was determined by GC‒MS. To study the anti-inflammatory and antioxidative properties of TLEO, we induced HaCaT and RAW264.7 cells by LPS. TLEO (0.001%-0.1%, v/v) was used to treat inflamed cells with dexamethasone (DEX, 10 μg/mL) as the standard drug. A variety of tests were carried out, including biochemical assays, ELISA, RT‒PCR, and western blotting. Docking of components was performed to predict potential ligands. RESULTS: The GC‒MS analysis revealed that 53 compounds (> 0.01%) represented 99.76% of the TLEO, and the majority of them were esters. TLEO not only reduced the levels of oxidative stress indicators (NO, ROS, MDA, and iNOS at the mRNA and protein levels) but also protected the SOD and CAT activities. According to the RT‒PCR, ELISA, and Western blot results, TLEO decreased inflammation by inhibiting the expression of TNF-α, IL-1β, IL-6, and key proteins (IκBα, NF-кB p65, p50, JNK, and p38 MAPK) in MAPK-NF-кB signaling. Molecular docking results showed that all of the components (> 1% in TLEO) were potent candidate ligands for further research. CONCLUSION: The theoretical evidence for TLEO in this study supported its use in skin care as a functional ingredient for cosmetics and pharmaceutics.