Camellia japonica oil suppressed asthma occurrence via GATA-3IL-4 pathway and its effective and major component is oleic acid

Background In December 2016, WHO released a report stating that in 2015 there were 383,000 deaths caused by asthma and 235 million people suffering from asthma. As there are many adverse effects associated with the currently-used asthma drugs, new anti-asthmatic drugs need to be developed. Purpose In order to find new drug candidates with safe and low side effects, the anti-asthmatic function and mechanism of C. japonica oil were evaluated, and its active ingredients were analyzed for use in an ovalbumin asthma murine model. Study design and methods The study consisted of six groups: control; ovalbumin group; and dexamethasone group as a positive control; and 10, 100, and 500 mg/kg C. japonica oil treatment groups. In order to measure the anti-asthmatic effect of C. japonica oil, WBC and differential cell count in BALF, IgE in serum, morphological changes in pulmonary system, and gene and protein levels such as IFN-γ, IL-12p40, IL-4, IL-5, IL-6, TNF-α, and IL-6 were all evaluated. Results C. japonica oil had an anti-asthmatic effect and significantly controlled eosinophil in BALF, Th2-related factors such as GATA-3 that is Th2 cell transcription factor, IL-4, IL-5, and IL-13, and TNF-α in the lung. It also dose-dependently modulated inflammatory cells, T-bet, IL-12p40, and IL-6. Oleci acid was the major gradient (52.89%) in C. japonica oil and also had anti-asthmatic effects such as the downregulation of inflammatory cells, WBC, and eosinophil in BALF, IgE in serum, and morphological changes in the lung. Conclusion We concluded that C. japonica oil is a new anti-asthmatic drug candidate and that oleic acid is the major anti-asthmatic ingredient in C. japonica oil.