Screening Matrix Metalloproteinase Inhibitors From Traditional Chinese Medicinal Library

Matrix metalloproteinases (MMPs) are a family of zinc dependent endopeptinases known to degrade the components of the extracellular matrix (ECM), they have emerged as critical molecules that mediate the remodeling of ECM in both physiological and pathological conditions. Based on their substrate specificity and primary structure, the MMP family can be subdivided into six groups: collagenases, gelatinases, stromelysins, Matrilysins, membrane type (MT) and heterogeneous subgroup. MMPs can degrade ECM components, other proteases, clotting factors, chemotactic molecules, latent growth factors, growth-factor binding proteins, adhesion molecules, cell surface receptors etc. Thereby, MMPs mediste the synthesis and secretion of cytokine, growth factor, hormone, cell-cell adhesion molecules receptors and control cell migration, proliferation, morphogenesis and apoptosis and regulate tumor expansion, angiogenesis and dissemination. In vivo, it is important that the activity of these enzymes is kept under tight control. The activity of MMPs is controlled at the following three levels: transcription, activation of the latent proenzymes, and inhibition by their endogenous inhibitors, the TIMPs. The development of many diseases, such as tumor, rheumatoid arthritis, osteoarthritis and cardiovascular diseases, all relate to the abnormal of MMPs activities. Therefore, the regulation of MMPs activities is significant to the treatment of these diseases. From last 1990's, the development of MMPs inhibitors are more and more rapidly. According the different sources of MMPs inhibitors, they can divided into four groups: endogenous tissue inhibitors of metalloproteinases (TIMPs); matrix metalloproteinase inhibitors (MMPIs) that may be derived from natural resources such as herbs, plants, fruits, and other agriculture products; synthetic MMPs inhibitors; some small peptide screening from Phage display libraries. Currently, the research focus on the matrix metalloproteinase inhibitors (MMPIs ) that may be derived from natural resources such as herbs, plants, fruits, and other agriculture products and the synthesis MMPs inhibitors.However, because of the incomplete understanding of the function of MMPs, non-specific and side effects of MMPs inhibitors, although earlier studies can lead to highly effectively inhibit the activity of MMPs. and effectively prevent tumor growth and metastasis, but the results are not satisfactory clinical treatment of cancer, eventually led to the failure of the latter part of the clinical examination. Along with the continuous deepening of the understanding of MMPs function, the researching and screening MMPs inhibitors with high specificity and low toxicity are becoming increasingly important. According to the reports, currently, some research institutions have isolated new and potentially beneficial compounds which have been shown to exhibit some degree of MMPI activities from herbs, plants, fruits, and other agriculture products, but they are far less potent and specific than the TIMP family. These natural compounds include long chain fatty acids, epigallocatechin gallate (EGCG) and other polyphenols, flavonoids, and a variety of other natural compounds.In the guidance of the clinical application and the theories of traditional Chinese medicine, we intend to apply biochemistry, enzymology, and natural medicinal chemistry and cell biology methods, isolate and screen MMPs inhibitors with high specificity and low toxicity, develop new drug targeting to MMPs.According to the classification of traditional Chinese medicine (TCM), we choose 185 kinds of TCM to build a traditional Chinese medicinal Library. From185 kinds of TCM, we screen a total of 62 types of Chinese herbal extracts inhibited MMP-16. Of these, five have a strong inhibitory effect (IC50?1μg/ml), thirty three have less strong inhibitory effect (1μg/ml≤IC50≤30μg/ml), and other twenty two can inhibit MMP-16 at a high concentration (30μg/ml?IC50?60μg/ml). Three primary extracts (Stir-baked Fructus Gardeniae, Polygoni Multiflori Caulis, Ramulus Cinnamomi) was further extracted by organic reagents and obtained five extracts (petroleum ether extract, chloroform extract, ethyl acetate extract, n-butyl alcohol extractand final water extract) with each herb. The water extract of Stir-baked Fructus Gardeniae can suppress MMP-16 activity and influence HT1080 cell shape and morphology. The ethyl acetate extract, n-butyl alcohol extract and water extract of Polygoni Multiflori Caulis inhibit MMP-9, MMP-14 and MMP-16, and among these extract the n-butyl alcohol extract and water extract inhibit the form of pseudopodia. The n-butyl alcohol extract and water extract of Ramulus Cinnamomi suppress MMP-2, MMP-9 and MMP-16.The result show the TCM which can inhibit MMPs activities was widely used to treat the Inflammation-related diseases. We hypothesis there be some MMPs inhibitors in these TCM extracts, and these products may inhibit the activity of MMPs to achieve the goals of treatment. The isolation of MMPs inhibitors from TCM is significant to research the treatment mechanism of TCM. Meanwhile, it is more important to develop the new drug targeting to MMPs.