ABSTRACT
Plasma membrane calcium ATPases (PMCAs) are a family of transmembrane proteins responsible for the extrusion of cytosolic Ca2+ to the extracellular milieu. They are important players of the calcium homeostasis possibly implicated in some important diseases. The reference inhibitors of PMCA extruding activity are on one hand ortho-vanadate (IC50 in the 30 mM range), and on the other a series of 12- to 20-mer peptides named caloxins (IC50 in the 100 µM scale). As for all integral membrane proteins, biochemistry and pharmacology are difficult to study on isolated and/or purified proteins. Using a series of reference blockers, we assessed a pharmacological window with which we could study the functionality of PMCAs in living cells. Using this system, we screened for alternative versions of caloxins, aiming at shortening the peptide backbone, introducing non-natural amino acids, and overall trying to get a glimpse at the structure-activity relationship between those new peptides and the protein in a cellular context. We describe a short series of equipotent 5-residue long analogues with IC50 in the low µM range.
Subject(s)
Calcium , Plasma Membrane Calcium-Transporting ATPases , Calcium/metabolism , Cell Membrane/metabolism , Membrane Proteins/metabolism , Peptides/metabolism , Peptides/pharmacology , Plasma Membrane Calcium-Transporting ATPases/metabolism , Structure-Activity RelationshipABSTRACT
Melanin-concentrating hormone (MCH) is a 19 amino acid long peptide found in the brain of animals, including fishes, batrachians, and mammals. MCH is implicated in appetite and/or energy homeostasis. Antagonists at its receptor (MCH-R1) could be major tools (or ultimately drugs) to understand the mechanism of MCH action and to fight the obesity syndrome that is a worldwide societal health problem. Ever since the deorphanisation of the MCH receptor, we cloned, expressed, and characterized the receptor MCH-R1 and started a vast medicinal chemistry program aiming at the discovery of such usable compounds. In the present final work, we describe GPS18169, a pseudopeptide antagonist at the MCH-R1 receptor with an affinity in the nanomolar range and a Ki for its antagonistic effect in the 20 picomolar range. Its metabolic stability is rather ameliorated compared to its initial parent compound, the antagonist S38151. We tested it in an in vivo experiment using high diet mice. GPS18169 was found to be active in limiting the accumulation of adipose tissues and, correlatively, we observed a normalization of the insulin level in the treated animals, while no change in food or water consumption was observed.
Subject(s)
Anti-Obesity Agents/chemistry , Obesity/drug therapy , Receptors, Pituitary Hormone/antagonists & inhibitors , Adipose Tissue/drug effects , Alkynes/chemistry , Aminobutyrates/chemistry , Animals , Anti-Obesity Agents/pharmacology , Appetite/drug effects , Aspartic Acid/chemistry , Disease Models, Animal , Drug Discovery , Glutamic Acid/chemistry , Glycine/analogs & derivatives , Glycine/chemistry , HEK293 Cells , Hepatocytes/drug effects , Homeostasis/drug effects , Humans , Insulin/metabolism , Lactams/chemistry , Male , Mice , Mice, Inbred C57BL , Rats , Structure-Activity Relationship , Tissue Distribution , Triazoles/chemistryABSTRACT
Selective and potent inhibitors of activated thrombin activatable fibrinolysis inhibitor (TAFIa) have the potential to increase endogenous and therapeutic fibrinolysis and to behave like profibrinolytic agents without the risk of major hemorrhage, since they do not interfere either with platelet activation or with coagulation during blood hemostasis. Therefore, TAFIa inhibitors could be used in at-risk patients for the treatment, prevention, and secondary prevention of stroke, venous thrombosis, and pulmonary embolisms. In this paper, we describe the design, the structure-activity relationship (SAR), and the synthesis of novel, potent, and selective phosphinanes and azaphosphinanes as TAFIa inhibitors. Several highly active azaphosphinanes display attractive properties suitable for further in vivo efficacy studies in thrombosis models.
Subject(s)
Aza Compounds/pharmacology , Carboxypeptidase B2/antagonists & inhibitors , Cyclic P-Oxides/pharmacology , Fibrinolytic Agents/pharmacology , Phosphinic Acids/pharmacology , Protease Inhibitors/pharmacology , Animals , Aza Compounds/chemical synthesis , Aza Compounds/metabolism , Carboxypeptidase B2/metabolism , Catalytic Domain , Cyclic P-Oxides/chemical synthesis , Cyclic P-Oxides/metabolism , Fibrinolysis/drug effects , Fibrinolytic Agents/chemical synthesis , Fibrinolytic Agents/metabolism , Humans , Male , Molecular Docking Simulation , Molecular Structure , Phosphinic Acids/chemical synthesis , Phosphinic Acids/metabolism , Protease Inhibitors/chemical synthesis , Protease Inhibitors/metabolism , Protein Binding , Rats, Sprague-Dawley , Structure-Activity RelationshipABSTRACT
We have developed versatile methods toward the synthesis of a variety of piperidine/piperazine bridged isosteres of pridopidine. The compounds were assessed against the D2 receptor in agonist and antagonist modes and against the D4 receptor in agonist mode. hERG Binding and the ADME profiles were studied.
Subject(s)
Drug Design , Piperazine/chemistry , Piperidines/chemistry , Animals , Bridged Bicyclo Compounds/chemical synthesis , Bridged Bicyclo Compounds/chemistry , Bridged Bicyclo Compounds/pharmacology , Crystallography, X-Ray , Dopamine Antagonists/chemical synthesis , Dopamine Antagonists/chemistry , Dopamine Antagonists/pharmacology , ERG1 Potassium Channel/metabolism , Humans , Magnetic Resonance Spectroscopy , Mice , Piperazine/chemical synthesis , Piperazine/pharmacology , Piperidines/chemical synthesis , Piperidines/pharmacology , Receptors, Dopamine D2/agonists , Receptors, Dopamine D4/agonists , Receptors, Dopamine D4/antagonists & inhibitors , Structure-Activity RelationshipABSTRACT
Plasminogen activator inhibitor-1 (PAI-1) is the main inhibitor of the tissue type and urokinase type plasminogen activators. High levels of PAI-1 are correlated with an increased risk of thrombotic events and several other pathologies. Despite several compounds with in vitro activity being developed, none of them are currently in clinical use. In this study, we evaluated a novel PAI-1 inhibitor, annonacinone, a natural product from the Annonaceous acetogenins group. Annonacinone was identified in a chromogenic screening assay and was more potent than tiplaxtinin. Annonacinone showed high potency ex vivo on thromboelastography and was able to potentiate the thrombolytic effect of tPA in vivo in a murine model. SDS-PAGE showed that annonacinone inhibited formation of PAI-1/tPA complex via enhancement of the substrate pathway. Mutagenesis and molecular dynamics allowed us to identify annonacinone binding site close to helix D and E and ß-sheets 2A.
Subject(s)
4-Butyrolactone/analogs & derivatives , Fibrinolytic Agents/administration & dosage , Plasminogen Activator Inhibitor 1/metabolism , 4-Butyrolactone/administration & dosage , 4-Butyrolactone/chemistry , 4-Butyrolactone/pharmacology , Animals , Binding Sites , Down-Regulation , Drug Evaluation, Preclinical , Fibrinolytic Agents/chemistry , Fibrinolytic Agents/pharmacology , Humans , Indoleacetic Acids/administration & dosage , Indoleacetic Acids/pharmacology , Mice , Models, Animal , Models, Molecular , Molecular Docking Simulation , Plasminogen Activator Inhibitor 1/chemistry , Plasminogen Activator Inhibitor 1/genetics , Protein Structure, Secondary , ThrombelastographyABSTRACT
The 1,5-benzothiazepine-4-one scaffold was earlier shown to provide efficient protease inhibitors. In this contribution, we describe its use in the design of factor VIIa/tissue factor inhibitors. A series containing a scaffold non-substituted on its aryl part led to compound 20 with an IC(50) of 2.16 microM. Following molecular modelling studies of this compound, a second series was prepared, which necessitated the synthesis of protected 7- or 8-substituted 1,5-benzothiazepine-4-one derivatives.
Subject(s)
Drug Delivery Systems/methods , Drug Design , Factor VIIa/antagonists & inhibitors , Thiazepines/chemical synthesis , Thromboplastin/antagonists & inhibitors , Drug Evaluation, Preclinical/methods , Factor VIIa/metabolism , Humans , Thiazepines/administration & dosage , Thiazepines/pharmacology , Thromboplastin/metabolismABSTRACT
A series of thieno[3,2-b]pyrroloazepinones derivatives related to Hymenialdisine were prepared and tested for CHK1 inhibitory activity. Nanomolar inhibitions were achieved when electron-withdrawing substituents were introduced at position 3 of the thiophene ring.
Subject(s)
Antineoplastic Agents/chemical synthesis , Azepines/chemical synthesis , Chemistry, Pharmaceutical/methods , Protein Kinases/metabolism , Pyrroles/chemical synthesis , Antineoplastic Agents/pharmacology , Azepines/pharmacology , Checkpoint Kinase 1 , Drug Design , Drug Screening Assays, Antitumor , Electrons , Humans , Inhibitory Concentration 50 , Models, Chemical , Molecular Structure , Neoplasms/drug therapy , Pyrroles/pharmacology , Structure-Activity Relationship , Thiophenes/chemistryABSTRACT
The synthesis and evaluation of inhibitors of activated protein C (aPC) are reported. This serine protease is partly responsible for the degradation of factor VIIIa, involved in the regulation of bleeding in hemophilia A. Benzamidine-containing derivatives were found to be potent aPC inhibitors, some of them showing selectivity against the procoagulant protease thrombin. Moreover, compound 1 significantly restored the generation of thrombin in hemophiliac plasma.
