A phenyl ethanoid,
salidroside (SAL), and two
secoiridoids, 8(E)-nuezhenide (NZD) and
ligustroside (LIG), were isolated from fruits of Ligustrumjaponicum, used as traditional
folk medicine, and their chemical structures were elucidated by the comparison of spectral data with published literature.
Matrix metalloproteinases (
MMPs) are major
enzymes that play crucial roles in the
metastasis and invasive behavior of
tumors. In particular, MMP-2 and MMP-9, regulated by the MAPK signaling pathways, including p38, ERK and JNK, are known to play a key role in the degradation of the basement membrane. In the present study, the effects of SAL, NZD and LIG on the expression of MMP-2 and -9 were examined in
phorbol 12-myristate 13-acetate (PMA)-induced HT 1080 cells. All the compounds significantly lowered the amount of MMP-2 and MMP-9 released, as determined by
gelatin zymography and ELISA. In addition, the
mRNA and
protein expression levels of MMP-2 and MMP-9 were significantly suppressed, as measured by RT-PCR and Western blotting. According to the Western blotting assay, SAL and LIG effectively reduced the expression of MMP-2 in a dose-dependent manner. NZD lowered the expression of MMP-9 in a similar way. The phosphorylation of p38, ERK and JNK was also significantly suppressed by these compounds. These findings suggest that all the compounds regulate the release and expression of MMP-2 and MMP-9 via MAPK signaling pathways.