FIG. 1.

Synthetic triterpenoid, CDDO-Me potently reduces levels of circulating IL-12p70 and IFN-γ (A) and levels of IL-6, IL-17, and IL-23 (B) in response to in vivo lipopolysaccharide (LPS) challenge. Cytokine levels were measured from plasma collected 5 h after mice (n = 6 mice per group) were challenged with LPS (300 μg IP). Mice were pretreated with low-dose LPS (25–50 μg intraperitoneal injection for 2 consecutive days prior to LPS challenge, Days -3 and -2), with vehicle alone (DMSO 100 μL, Day -2) or with the synthetic triterpenoid, CDDO-Me (100 nmol IP, Day -2). Mice did not receive any pretreatment on Day -1 (rest). All LPS challenges occurred 48 h (Day 0) after the last pretreatment (LPS, DMSO, or CDDO-Me) was administered. Untreated, age-matched control mice (none) were similarly challenged with LPS on Day 0. Cytokine levels (mean ± SEM) for each experimental group from 1 of 3 independent experiments are shown. Indicated P values (unpaired, 2-tailed t-tests) are for mean comparisons between groups pretreated with either low-dose LPS (LPS) or synthetic triterpenoid (CDDO-Me) and their respective control group (none or DMSO, respectively) unless otherwise indicated. NS = not statistically significant (P > 0.05).