Discovery of a new selective inhibitor of A Disintegrin And Metalloprotease 10 (ADAM-10) able to reduce the shedding of NKG2D ligands in Hodgkin's lymphoma cell models

Hodgkin's lymphoma (HL) is the most common malignant lymphoma in young adults in the western world. This disease is characterized by an overexpression of ADAM-10 with increased release of NKG2D ligands, involved in an impaired immune response against tumor cells. We designed and synthesized two new ADAM-10 selective inhibitors, 2 and 3 based on previously published ADAM-17 selective inhibitor 1. The most promising compound was the thiazolidine derivative 3, with nanomolar activity for ADAM-10, high selectivity over ADAM-17 and MMPs and good efficacy in reducing the shedding of NKG2D ligands (MIC-B and ULBP3) in three different HL cell lines at non-toxic doses. Molecular modeling studies were used to drive the design and X-ray crystallography studies were carried out to explain the selectivity of 3 for ADAM-10 over MMPs

Zinc binding and chelating compounds as inhibitors of bacterial metalloproteases and human matrix metalloproteases

Bacterial multi-drug resistance is a major health problem worldwide. Inhibition of bacterial virulence is suggested to be a promising strategy in the development of new antibacterial drugs. The present work has focused on identifying new inhibitors of the bacterial virulence factors thermolysin (TLN), pseudolysin (PLN, LasB) and aureolysin (ALN), which are all zinc metalloproteases (MPs) using enzyme kinetics studies and molecular modelling. A chemical group chelating the catalytic zinc ion of MPs, referred to as the zinc-binding group (ZBG) (e.g., phosphinate (PO2), carboxylate (COO-), thiolate (S-) and hydroxamic acid HONH-CO, sulfhydryl, etc.) is important for essential inhibition. The strategy in the present work was to use different compounds with a putative ZBG, including compounds with nitrogen as the zinc donor atom. The structure of the active site cleft of the virulence factors is very similar to that of the matrix metalloproteases (MMPs) and other human zinc MPs. Bacterial virulence inhibitors as drugs against bacterial infections should have limited effects on human endogenous zinc MPs. Therefore, we also tested their inhibition of human MMP-9 and MMP-14. Several compounds were found to inhibit the activity of the virulence factors, but most of the compounds also inhibited the human enzymes. However, the studies showed that the bisphosphonate-containing compound RC2 bound stronger to the bacterial virulence factors than to the human enzymes, while the catechol-containing compound BF471 was found to inhibit ALN. To our knowledge, this is the first reported small molecule inhibiting ALN. These compounds may be used as scaffolds to design new and potentially stronger inhibitors of bacterial virulence factors with therapeutic potential

Peptides and Peptidomimetics as Inhibitors of Enzymes Involved in Fibrillar Collagen Degradation

Collagen fibres degradation is a complex process involving a variety of enzymes. Fibrillar collagens, namely type I, II, and III, are the most widely spread collagens in human body, e.g., they are responsible for tissue fibrillar structure and skin elasticity. Nevertheless, the hyperactivity of fibrotic process and collagen accumulation results with joints, bone, heart, lungs, kidneys or liver fibroses. Per contra, dysfunctional collagen turnover and its increased degradation leads to wound healing disruption, skin photoaging, and loss of firmness and elasticity. In this review we described the main enzymes participating in collagen degradation pathway, paying particular attention to enzymes degrading fibrillar collagen. Therefore, collagenases (MMP-1, -8, and -13), elastases, and cathepsins, together with their peptide and peptidomimetic inhibitors, are reviewed. This information, related to the design and synthesis of new inhibitors based on peptide structure, can be relevant for future research in the fields of chemistry, biology, medicine, and cosmeceuticals

Synthesis, experimental evaluation and molecular modelling of hydroxamate derivatives as zinc metalloproteinase inhibitors

Manuscript. Published version available in European Journal of Medicinal Chemistry, Vol. 108, 27 January 2016, pp 141–153Enzymes of the M4 family of zinc-metalloproteinases are virulence factors secreted from gram-positive or gram-negative bacteria, and putative drug targets in the treatment of bacterial infections. In order to have a therapeutic value such inhibitors should not interfere with endogenous zinc-metalloproteinases. In the present study we have synthesised a series of hydroxamate derivatives and validated the compounds as inhibitors of the M4 enzymes thermolysin and pseudolysin, and the endogenous metalloproteinases ADAM-17, MMP-2 and MMP-9 using experimental binding studies and molecular modelling. In general, the compounds are stronger inhibitors of the MMPs than of the M4 enzymes, however, an interesting exception is LM2. The compounds bound stronger to pseudolysin than to thermolysin, and the molecular modelling studies showed that occupation of the S2’ subpocket by an aromatic group is favourable for strong interactions with pseudolysin

Inhibitory antibodies designed for matrix metalloproteinase modulation

The family of matrix metalloproteinases (MMPs) consists of a set of biological targets that are involved in a multitude of severe pathogenic events such as different forms of cancers or arthritis. Modulation of the target class with small molecule drugs has not led to the anticipated success until present, as all clinical trials failed due to unacceptable side effects or a lack of therapeutic outcome. Monoclonal antibodies offer a tremendous therapeutic potential given their high target selectivity and good pharmacokinetic profiles. For the treatment of a variety of diseases there are already antibody therapies available and the number is increasing. Recently, several antibodies were developed for the selective inhibition of single MMPs that showed high potency and were therefore investigated in in vivo studies with promising results. In this review, we highlight the progress that has been achieved toward the design of inhibitory antibodies that successfully modulate MMP-9 and MMP-14

Embelin inhibits TNF-α converting enzyme and cancer cell metastasis: molecular dynamics and experimental evidence

BACKGROUND: Embelin, a quinone derivative, is found in the fruits of Embelia ribes Burm (Myrsinaceae). It has been shown to have a variety of therapeutic potentials including anthelmintic, anti-tumor, anti-diabetic, anti-bacterial and anti-inflammation. Inflammation is an immunological response to external harmful stimuli and is regulated by an endogenous pyrogen and pleiotropic pro-inflammatory cytokine, tumor necrosis factor alpha (TNF-α). TNF-α production has been implicated in a variety of other human pathologies including neurodegeneration and cancer. Several studies have shown that the anti-inflammatory activity of embelin is mediated by reduction in TNF-α. The latter is synthesized as a membrane anchored protein (pro-TNF-α); the soluble component of pro-TNF-α is then released into the extracellular space by the action of a protease called TNF-α converting enzyme (TACE). TACE, hence, has been proposed as a therapeutic target for inflammation and cancer. METHODS: We used molecular docking and experimental approaches to investigate the docking potential and molecular effects of embelin to TACE and human cancer cell characteristics, respectively. RESULTS: We demonstrate that embelin is a potential inhibitor of TACE. Furthermore, in vitro studies revealed that it inhibits malignant properties of cancer cells through inactivation of metastatic signaling molecules including MMPs, VEGF and hnRNP-K in breast cancer cells. CONCLUSION: Based on the molecular dynamics and experimental data, embelin is proposed as a natural anti-inflammatory and anticancer drug

Selective Arylsulfonamide Inhibitors of ADAM-17: Hit Optimization and Activity in Ovarian Cancer Cell Models

Activated Leukocyte Cell Adhesion Mol. (ALCAM) is expressed at the surface of epithelial ovarian cancer (EOC) cells and is released in a sol. form (sALCAM) by ADAM-17-mediated shedding. This process is relevant to EOC cell motility and invasiveness, which is reduced by inhibitors of ADAM-17. In addn., ADAM-17 plays a key role in EGFR signalling and thus may represent a useful target in anticancer therapy. Herein we report our hit optimization effort to identify potent and selective ADAM-17 inhibitors, starting with previous mol. 1. A new series of secondary sulfonamido-based hydroxamates was designed and synthesized. The biol. activity of the newly synthesized compds. was tested in vitro on isolated enzymes and human EOC cell lines. The optimization process led to compd. 21, which showed an IC50 of 1.9 nM on ADAM-17 with greatly increased selectivity. This compd. maintained good inhibitory properties on sALCAM shedding in several in vitro assays

Differential expression of ADAMTS -1, -4, -5 and TIMP -3 in rat spinal cord at different stages of acute experimental autoimmune encephalomyelitis

Experimental autoimmune encephalomyelitis (EAE) is an animal model of inflammatory demyelination, a pathological event common to multiple sclerosis (MS). During CNS inflammation there are alterations in the extracellular matrix (ECM). A Disintegrin and Metalloproteinase with Thrombospondin motifs (ADAMTS) -1, -4 and -5 are proteases present in the CNS, which are able to cleave the aggregating chondroitin sulphate proteoglycans, aggrecan, phosphacan, neurocan and brevican. It is therefore important to investigate changes in their expression in different stages of EAE induction. We have investigated expression of ADAMTS-1, -4, -5 and Tissue inhibitor of metalloproteinase (TIMP) -3, by real-time RT-PCR. We have also examined protein expression of ADAMTS-1, -4 and -5 by western blotting and immunocytochemistry in spinal cord from animals at different stages of disease progression. Our study demonstrated a decrease in ADAMTS-4 mRNA and protein expression. TIMP-3 was decreased at the mRNA level although protein levels were increased in diseased animals compared to controls. Our study identifies changes in ADAMTS expression during the course of CNS inflammation which may contribute to ECM degradation and disease progression.</p