FIGURE 1

Emodin suppresses inflammatory response and oxidative stress in vitro and in vivo. (A) The chemical structure of emodin. (B) Emodin inhibits the production of inflammatory factors TNF-α, IL-6, MCP-1, and MIP-2 in LPS-induced RAW264.7 cells. RAW264.7 cells were pretreated with emodin (30, 35, or 40 μM) for 2 h and then treated with LPS (100 ng/ml) for 18 h. The levels of TNF-α, IL-6, MCP-1, and MIP-2 in supernatant were measured by ELISA. (C) Emodin inhibits oxidative stress in LPS-induced RAW264.7 cells. RAW264.7 cells were pretreated with emodin (30, 35, or 40 μM) for 2 h and then treated with LPS (100 ng/ml) for 18 h. The cells were collected and the ROS production was determined by flow cytometric analysis. Data are presented as mean ± SEM, n = 3. ^***p < 0.001 compared with the control group, ^###p < 0.001 compared with the LPS group. (D) Protective effects of emodin on zebrafish challenged by LPS. 3 dpf zebrafish larvae were yolk-microinjected with LPS (0.5 mg/ml), and then treated with emodin (0.05 μM) or DEX (5 μg/ml). Survival of zebrafish larvae was assessed within 72 h. PBS-microinjected zebrafish larvae were served as the negative control. Data are presented as mean ± SEM. ^***p < 0.001 compared with the PBS group, ^###p < 0.001 compared with the LPS group.