Crocetin Exerts Its Anti-inflammatory Property in LPS-Induced RAW264.7 Cells Potentially via Modulation on the Crosstalk between MEK1/JNK/NF-κB/iNOS Pathway and Nrf2/HO-1 Pathway

Figure 1

The effects of crocetin on nitric oxide production and iNOS expression. (a) The structure of crocetin. (b) The cytotoxicity assay of crocetin in RAW264.7 cells. Cytotoxicity assay was performed as described in Materials and Methods. (c) Crocetin inhibits LPS-induced NO release. RAW264.7 cells were treated with crocetin (10–20 μg/ml) for 1 h before starvation in serum-free medium for another 2.5 h and then exposed to 40 ng/ml LPS for an additional 12 h. The amount of NO in medium was measured as described in Materials and Methods. (d) Crocetin suppresses LPS-induced iNOS expression. RAW264.7 cells were pretreated with crocetin (10–20 μg/ml) for 1 h before starvation in serum-free medium for 2.5 h and then exposed to 40 ng/ml LPS for an additional 12 h of treatment. The expressions of proteins were detected by Western blot analysis using their corresponding antibodies. Data are presented as the of at least triplicate tests. and vs. LPS-treated cells.

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