Anti-metalloproteinase-9 Activities of Selected Indonesian Zingiberaceae Rhizome Extracts in Lipopolysaccharide-induced Human Vascular Endothelial Cells In Vitro

Atherosclerosis arises from chronic inflammation triggered by bacterial infection that activates degradation process by matrix metalloproteinases (MMPs). Zingiberaceae, a group of tropical food crops grown in Indonesia and other Southeast Asia regions, has been traditionally used for food coloring, seasoning, culinary, and medicinal purposes. However, its efficacy as natural vascular protection has not been explored. Our previous studies demonstrated that Kaempferia pandurata Roxb. possesed MMP-2 and MMP-9 inhibitory effects in human gingival and oral epithelial cells induced by Porphyromonas gingivalis, suggesting its potential therapeutic for natural periodontal therapy. Here, we examined the effects of 10 Indonesian Zingiberaceae rhizome extracts on inhibition of MMP-9 expression in human vascular endothelial cells treated with lipopolysaccharide (LPS) in vitro by conducting gelatin zymogram, Western blotting, and RT-PCR assays. LPS (2µg/ml) significantly elevated the expression of MMP-9 secretion, protein, and mRNA in vascular endothelial cells. Selected Zingiberaceae exctracts (1 and 5µg/ml), i.e. Curcuma xanthorrhiza, C. aeruginosa, C. mangga, C. longa, Kaempferia galanga, Alpinia galanga, and Zingiberaceae officinale, effectively attenuated the expression of MMP-9 secretion, protein, and mRNA in LPS-induced vascular endothelial cells. Furthermore, MMP-9 expression was specifically blocked by MAPK inhibitors, i.e. PD98059 (ERK1/2 inhibitor), SB203580 (p38 inhibitor), SP600125 (JNK inhibitor), and PI3K inhibitor (LY294002), indicating that MAPK and PI3K signaling pathways are involved in regulation of MMP-9 gene expression in LPS-induced vascular endothelial cells. These results suggest that selected Indonesian Zingiberaceae rhizomes with potent MMP-9 inhibitory activity may have potentials on prevention and protection of vascular diseases particularly atherosclerosis.