Sudachitin Inhibits Matrix Metalloproteinase-1 and -3 Production in Tumor Necrosis Factor-α-Stimulated Human Periodontal Ligament Cells

Sudachitin, a polymethoxylated flavonoid found in the skin of Citrus sudachi, is a biologically active substance. The aim of this study was to examine whether sudachitin could be used to inhibit the expression of matrix metalloproteinase (MMP)-1 and MMP-3, which are involved in the destruction of periodontal tissues in periodontal lesions, in tumor necrosis factor (TNF)-α-stimulated human periodontal ligament cells (HPDLC). Sudachitin suppressed TNF-α-induced MMP-1 and MMP-3 production in HPDLC. On the other hand, it enhanced tissue inhibitor of metalloproteinase (TIMP)-1 expression. The level of Akt phosphorylation in the TNF-α-stimulated HPDLC was decreased by sudachitin treatment. Moreover, an Akt inhibitor reduced MMP-1 and MMP-3 production and increased TIMP-1 production. These findings indicate that sudachitin reduces MMP-1 and MMP-3 production in TNF-α-stimulated HPDLC by inhibiting the Akt pathway.