Curcumin inhibits IL1 alpha and TNF-alpha induction of AP-1 and NF-kB DNA-binding activity in bone marrow stromal cells.

We have previously demonstrated that anti-inflammatory and antioxidant compound curcumin (diferuloyl-methane) inhibits the expression of monocyte chemoattractant protein-1 (MCP-1/JE) in bone marrow stromal cells by suppressing the transcriptional activity of the MCP-1/JE gene. Since both AP-1 (TRE) and NF-kB (kB) binding motifs are present in the promoter of MCP-1/JE gene, we examined the effect of curcumin on IL1 alpha- and TNF-alpha-induced activation of ubiquitous transcription factors AP-1 and NF-kB by electrophoretic mobility shift assay and Western blotting. IL1 alpha and TNF-alpha rapidly induced both AP-1 and NF-kB DNA binding activities in +/+(-)1.LDA11 stromal cells. However, treatment of these cells with curcumin blocked the activation of AP-1 and NF-kB by both cytokines. These data suggest that inhibition of MCP-1/JE transcription by curcumin involves blocking of AP-1 and NF-kB activation by IL1 alpha or TNF-alpha.