LPS-induced systemic inflammation.

Eight-week-old mice were injected i.p. with echinatin (20 or 40 mg/kg) for 1 hour and were then injected i.p. with LPS (20 mg/kg) (0111:B4; MilliporeSigma). After 2 hours, the mice were sacrificed, and the serum samples were collected; 10 mL of ice-cold PBS was used to wash the peritoneal cavities. The levels of plasma IL-1β and TNF-α were measured by ELISA. The polymorphonuclear neutrophils in peritoneal lavage fluid was analyzed by flow cytometry by staining Ly6G and CD11b. For endotoxic shock model, 8-week-old mice were injected with echinatin (20 or 40 mg/kg) i.p. for 1 hour and then injected with LPS (20 mg/kg) i.p. Mice were monitored for lethality for 3 days.