The Protective Effects of Terpinen-4-ol on LPS-Induced Acute Lung Injury via Activating PPAR-γ

Terpinen-4-ol, the major constituent of tea tree oil, has been reported to have anti-inflammatory effect. However, whether terpinen-4-ol could attenuate LPS-induced inflammation in lung tissues remains unclear. In the present study, we aimed to investigate the protective effects of terpinen-4-ol on LPS-induced acute lung injury (ALI) in mice. Terpinen-4-ol could inhibit LPS-induced ALI as confirmed by the decreased lung histopathological changes, MPO activity, and lung W/D ratio caused by terpinen-4-ol. The production of TNF- and IL-1 in the BALF was suppressed by the treatment of terpinen-4-ol. Western blot analysis showed that terpinen-4-ol significantly attenuated LPS-induced phosphorylation of IB and NF-B p65. Furthermore, the expression of PPAR- was dose-dependently upregulated by the treatment of terpinen-4-ol. In conclusion, the results of this study indicated that terpinen-4-ol inhibited LPS-induced ALI via activating PPAR-, which subsequently attenuated LPS-induced NF-B activation and inflammatory response.