Cells were treated with compounds 1 and 2 at indicated concentrations. immunoblotting. Compound 1 was shown to be slightly more active to inhibit MMP-2 and -9, however, compound 2 showed more regular dose-dependency during inhibition. In conclusion, this study suggested that GL-3 and oleonuezhenide were notable natural origin potent MMP inhibitors and could serve as lead compounds for development of anti-invasive MMP inhibitors against tumor metastasis. fructus, MAPK, MMP 1. Introduction Matrix metalloproteinases (MMPs) are a family of Zn2+ dependent endopeptidases with more than 20 members which take roles in several diseases and complications such as chronic inflammation, periodontitis, chronic obstructive pulmonary disease, arteriosclerosis and arthritis [1,2,3]. MMPs are also known to be crucial in the progression, metastasis and invasion Rabbit Polyclonal to RPL26L of the tumor cells owing to their ability to degrade and regenerate extracellular matrix [4,5]. This ability to degrade and reshape the extracellular matrix made MMPs also a key factor in the aging process of the skin and forming of the wrinkles which are mostly due to impaired collagen production and structure [6,7]. In particular, the secondary tumor growth where metastatic cancer cells from malignant tumors travel through the body via lymphatic system is closely-linked with the actions of several MMPs around the extracellular matrix of the target tissue for invasion [8,9]. It is mainly observed through MMP-mediated degradation of basement membrane proteins. The degrees of expression of two Trimebutine maleate members of the MMP family, MMP-2 (gelatinase-A, 72 kDa) and MMP-9 (gelatinase-B, 92 kDa) were identified to be in closely related relationship with the metastasis and invasion ability of tumor cells, particularly secondary tumor growth [10,11]. As such, the primary cause of death in cancer patients is due to the secondary tumor growth rather than early diagnosed initial tumors. Hence, obtaining a material that inhibits the enzymatic activity and/or production of MMPs is regarded as an important strategy towards overcoming cancer growth and linked mortality. For this reason, considerable efforts were directed into MMP inhibitory research and development [12,13,14]. Most of the reported MMP inhibitors are of synthetic origin and found through chemical synthesis pathways, however, research on MMP inhibitors from natural products has only been of increasing interest recently [15,16,17]. (Waxleaf privet) is an evergreen broad-leaved tree that is natively distributed in the western and southern coastal regions of Korea as well as the islands reachable from those shores. The small black oval fruit of this tree is a part of traditional folk medicine practices to cure liver and kidney problems and to treat hair whitening although it is also found to be toxic if consumed abundantly . Studies revealed several bioactive properties of the fruits such as antioxidant, anti-inflammatory, vascular relaxation, whitening and osteogenic stimulation effects [19,20,21]. In the process of developing a natural origin MMP inhibitor from terrestrial and marine plants, fruits of the and respectively [22,23]. Chemical structures of these compounds were readily determined by a combination of spectroscopic analysis and comparison with data described in the literature (Physique 1). Their NMR spectral data (available in the Supplementary Material) were well matched with Trimebutine maleate those reported in the same NMR solvent . Open in a Trimebutine maleate separate window Physique 1 Chemical structures of isolated compounds GL-3 (1) and oleonuezhenide (2). 2.2. Inhibition of MMP-2 and MMP-9 Enzymatic Activity Prior to in vitro assays, biocompatibility of the isolated compounds GL-3 (1) and oleonuezhenide (2) was tested via evaluation of their toxic presence in HT-1080 human fibrosarcoma cell line. Cells treated with compounds 1 and 2 showed viability above 80% of untreated control cells at the concentrations 10, 50 and 100 M (Physique 2). Further assays were conducted using these dose range and therefore, any MMP inhibitory effect of the compounds was defined not from cellular toxicity produced via compounds but other pathways stated. Open in a separate window Physique 2 Effect of (a) GL-3 (1) and (b) oleonuezhenide (2) around the viability of HT-1080 human fibrosarcoma cells evaluated by MTT assay. Cell viability was given percentage of untreated control cells (Con). Values are mean SD of three impartial experiments. aCc Means with different letters are significantly different at 0.05 level. MMPs are involved in the metabolic pathways associated with cancer cell metastasis, oxidative stress,.