Ingredients from Litsea garrettii as Potential Preventive Agents against Oxidative Insult and Inflammatory Response

Figure 6

MPP inhibits LPS-induced inflammatory response in RAW 264.7 macrophages. (a) MPP had no cytotoxicity at doses ≤ 100 μM. Cells were treated with indicated doses of MPP for 48 h, and the cell viability was determined by MTT assay. (b and c) MPP inhibited the LPS-induced NF-κB nuclear translocation. After being pretreated with 25 μM MPP for B or indicated doses of MPP for C or didox (100 μM) for 1 h, cells were cotreated with LPS (1 μg/mL) for 1 h and then subjected to indirect fluorescence staining and immunoblot analysis. (c) MPP inhibited the NF-κB-dependent luciferase activity. After being cotransfected with NF-κB firefly luciferase and TK-Renilla luciferase, cells were pretreated with MPP (25 μM) or didox (100 μM) for 1 h and cotreated with LPS (1 μg/mL) for 16 h. (d) MPP inhibited the LPS-stimulated activation of NF-κB p65 subunit, IκB-α, iNOS, and COX-2. Cells were cotreated with indicated doses of MPP or didox (100 μM) and LPS for 16 h, and then the protein levels were measured by immunoblot analysis. (e) MPP inhibited the LPS-stimulated activation of inflammatory cytokines TNF-α and IL-1β. The concentrations of cytokines were detected using the ELISA kits. Values were presented as mean ± SD (). , treated versus control; , , , treated versus LPS. C: control.

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