RÉSUMÉ
Aim: To explore the mechanism of the antiinflammatory effect of essential oils of Schizonepeta tenuifolia Briq. (EOST) by investigating the regulatory effect on NLRP3 inflammasome pathway. Methods: EOST (0. 226, 0. 452 g · kg-1) were continuously administered for five days. Thirty minutes after the last administration, the mice were intraperitoneally injected with LPS (0.015 g · kg-1, 10 mL · kg-1) to construct endotoxin poisoning, and relevant indicators for sample determination were taken 12 h after modeling. Determination of NO level in lung tissues by Griess method was performed. The expressions of NLRP3, ASC, caspase-1, IL-1β, iNOS and p65 mRNA in lung tissues were detected by qPCR. The expressions of P2X7R and Cathepsin B protein in lung tissues were assessed using immunohistochemistry. The NLRP3, caspase-1(p20), Pro-caspase-1, COP-1 protein ex pressions were detected by Western blot. Results: 0.226 g · kg-1 EOST could down-regulate the expressions of Cathepsin B and NLRP3 proteins in lung tissues of mice; 0.452 g · kg-1 EOST significantly reduced NO level, the expressions of NLRP3, iNOS, p65, IL-1β mRNA and P2X7R protein in lung tissues of mice; EOST (0.226, 0.452 g · kg-1) markedly reduced the. caspase-1 (p20) protein level and significantly increased COP1 protein level. Conclusions: The protective effect of EOST on endotoxin poisoning mice is closely related to its anti-inflammatory effects, which involves the inhibition of activation of NLRP3 inflammasome.