A Combinatorial Virtual Screening Approach Driving the Synthesis of 2,4-Thiazolidinedione-Based Molecules as New Dual mPGES-1/5-LO Inhibitors.

Dual inhibition of microsomal prostaglandin E2 synthase-1 (mPGES-1) and 5-lipoxygenase (5-LO), two key enzymes involved in pro-inflammatory eicosanoid biosynthesis, represents a new strategy for treating inflammatory disorders. Herein we report the discovery of 2,4-thiazolidinedione-based mPGES-1/5-LO dual inhibitors following a multidisciplinary protocol, involving virtual combinatorial screening, chemical synthesis, and validation of the biological activities for the selected compounds. Following the multicomponent-based chemical route for the decoration of the 2,4-thiazolidinedione core, a large library of virtual compounds was built (∼2.0×104 items) and submitted to virtual screening. Nine selected molecules were synthesized and biologically evaluated, disclosing among them four compounds able to reduce the activity of both enzymes in the mid- and low- micromolar range of activities. These results are of interest for further expanding the chemical diversity around the 2,4-thiazolidinedione central core, facilitating the identification of novel anti-inflammatory agents endowed with a promising and safer pharmacological profile.

Glucopyranosylbianthrones from the Algerian Asphodelus tenuifolius: Structural Insights and Biological Evaluation on Melanoma Cancer Cells.

Two new glucopyranosylbianthrones (1 and 2) were isolated from the aerial part of the plant Asphodelus tenuifolius, collected in Southwest Algeria. The 2D structures of 1 and 2 were defined by NMR analysis, HRESIMS data, and comparison with literature data. The comparison of experimental and calculated electronic circular dichroism and NMR data led to characterization of the ( M) and ( P) atropisomeric forms of the glucopyranosylbianthrones, asphodelins (1) and (2), respectively. The in vitro activities of these two metabolites were evaluated in human melanoma A375 cells, and both the compounds inhibited cell proliferation in a concentration-dependent manner, with IC50 values of 20.6 ± 0.8 and 23.2 ± 1.1 µM, respectively. Considering their biological profile, an inverse virtual screening approach was employed to identify and suggest putative anticancer interacting targets.

Identification by Inverse Virtual Screening of magnolol-based scaffold as new tankyrase-2 inhibitors.

The natural product magnolol (1) and a selection of its bioinspired derivatives 2-5, were investigated by Inverse Virtual Screening in order to identify putative biological targets from a panel of 308 proteins involved in cancer processes. By this in silico analysis we selected tankyrase-2 (TNKS2), casein kinase 2 (CK2) and bromodomain 9 (Brd9) as potential targets for experimental evaluations. The Surface Plasmon Resonance assay revealed that 3-5 present a good affinity for tankyrase-2, and, in particular, 3 showed an antiproliferative activity on A549 cells higher than the well-known tankyrase-2 inhibitor XAV939 used as reference compound.

Design, synthesis, and biological activity of hydroxamic tertiary amines as histone deacetylase inhibitors.

Herein we describe the design, synthesis, and biological evaluation of new hydroxamic tertiary amines as histone deacetylase (HDAC) inhibitors. These compounds have allowed us to clarify the influence of cap group dimension and hydrophobicity on HDAC inhibitory activity. This report also reveals the recognition pattern between the linear compounds and the histone deacetylase-like protein (HDLP) model receptor, and discusses the synthesis and in vitro evaluation of HDAC inhibitory activity in HeLa cell nuclear extracts. We obtained good qualitative agreement between experimental results and theoretical predictions, confirming that appropriately substituted hydroxamic tertiary amines are potential active HDAC inhibitors.

Anti-inflammatory and analgesic activity of a novel inhibitor of microsomal prostaglandin E synthase-1 expression.

In a previous study, we reported a new gamma-hydroxybutenolide derivative, 4-benzo[b]thiophen-2-yl-3-bromo-5-hydroxy-5H-furan-2-one (BTH), as inhibitor of microsomal prostaglandin E synthase-1 (mPGES-1) expression in lypopolysaccharide (LPS) stimulated RAW 264.7 and TPH-1 cells, without affecting cyclooxygenase-2 (COX-2). In this study, we evaluated the in vivo effect of BTH on some acute and chronic inflammatory animal models in relation to its inhibitory profile on mPGES-1 expression. In the zymosan-induced mouse air pouch model, BTH produced a dose-dependent inhibition of prostaglandin E(2) (PGE(2)) production and mPGES-1 protein expression in pouch exudates without any effect on COX-2 protein expression. This behavior was confirmed in the chronic model of collagen-induced arthritis, where administration of BTH (5 mg/kg) clearly reduced PGE(2) and mPGES-1 expression in joint tissues, whereas COX-2 was unaffected. These effects were accompanied by the suppression of clinical and histopathological manifestations of disease such as the loss of proteoglycan, and the destruction of surface cartilage. Other enzymes participating in the metabolism of arachidonic acid, such as prostaglandin I(2) synthase, tromboxane A(2) synthase or 5-lipoxygenase were unaffected by this compound. The acetic acid-induced hyperalgesia model in LPS-sensitized mice showed a dose-dependent analgesic effect of BTH, exerting an ED(50) value of 6.2 mg/kg. Our data suggest that inhibition of mPGES-1 protein expression in acute and chronic inflammatory models by BTH, could provide a potential therapeutic target and a pharmacological tool to discern the role of the inducible enzymes COX-2 and mPGES-1 in inflammatory pathologies.