ABSTRACT
Obesity and insulin resistance are primary risk factors for Non-Alcoholic Fatty Liver Disease (NAFLD). NAFLD is generally exhibited by non-progressive simple steatosis. However, a significant subset of patient's progress to nonalcoholic steatohepatitis (NASH) that is defined by the presence of steatosis, inflammation and hepatocyte injury with fibrosis. Unfortunately, there are no approved therapies for NAFLD or NASH and therefore therapeutic approaches are urgently needed. Niclosamide is an U.S. Food and Drug Administration (FDA)-approved anthelmintic drug that mediates its effect by uncoupling oxidative phosphorylation. Niclosamide and its salt forms, Niclosamide Ethanolamine (NEN), and Niclosamide Piperazine (NPP) have shown efficacy in murine models of diet induced obesity characterized by attenuation of the prominent fatty liver disease phenotype and improved glucose metabolism. While the exact mechanism(s) underlying these changes remains unclear, the ability to uncouple oxidative phosphorylation leading to increased energy expenditure and lipid metabolism or attenuation of PKA mediated glucagon signaling in the liver have been proposed. Unfortunately, niclosamide has very poor water solubility, leading to low oral bioavailability. This, in addition to mitochondrial uncoupling activity and potential genotoxicity have reduced enthusiasm for its clinical use. More recently, salt forms of niclosamide, NEN and NPP, have demonstrated improved oral bioavailability while retaining activity. This suggests that development of safer more effective niclosamide derivatives for the treatment of NAFLD and Type 2 Diabetes may be possible. Herein we explored the ability of a series of N-substituted phenylbenzamide derivatives of the niclosamide salicylanilide chemotype to attenuate hepatic steatosis using a novel phenotypic in vitro model of fatty liver and the high fat diet-fed mouse model of diet induced obesity. These studies identified novel compounds with improved pre-clinical properties that attenuate hepatic steatosis in vitro and in vivo. These compounds with improved drug properties may be useful in alleviating symptoms and protection against disease progression in patients with metabolic syndrome and NAFLD.
Subject(s)
Anti-Obesity Agents/pharmacology , Benzamides/pharmacology , Diet, High-Fat/adverse effects , Non-alcoholic Fatty Liver Disease/drug therapy , Obesity/drug therapy , Animals , Anti-Obesity Agents/chemistry , Anti-Obesity Agents/pharmacokinetics , Benzamides/chemistry , Benzamides/pharmacokinetics , Cell Respiration/drug effects , Cells, Cultured , Disease Models, Animal , Dose-Response Relationship, Drug , Drug Evaluation, Preclinical , Escherichia coli/drug effects , Hepatocytes/drug effects , Hepatocytes/metabolism , High-Throughput Screening Assays , Humans , Lipogenesis/drug effects , Liver/drug effects , Liver/metabolism , Male , Mice , Microsomes, Liver/drug effects , Microsomes, Liver/metabolism , Non-alcoholic Fatty Liver Disease/metabolism , Obesity/metabolism , Rats, Sprague-Dawley , Salmonella typhimurium/drug effectsABSTRACT
Starting from a weak omeprazole screening hit, replacement of the pyridine with a 1,3-benzodioxole moiety, modification of the thioether linkage, and substitution of the benzimidazole pharmacophore led to the discovery of nanomolar BRS-3 agonists.
Subject(s)
Omeprazole/chemistry , Receptors, Bombesin/agonists , Baculoviridae/metabolism , Benzimidazoles/chemistry , Brain/metabolism , Chemistry, Pharmaceutical/methods , Chlorofluorocarbons, Methane/chemistry , Drug Design , Drug Evaluation, Preclinical , Humans , Kinetics , Models, Chemical , Pyridines/chemistry , Receptors, Bombesin/chemistry , Sulfides/chemistryABSTRACT
A novel series of potent substituted anilinoquinolines were discovered as c-fms inhibitors. The potency could be manipulated upon modification of the C4 aniline and C7 aryl functionality. Pharmacokinetic analysis identified a metabolically stable analog suitable for further investigative work.
Subject(s)
Aniline Compounds/chemistry , Quinolines/chemical synthesis , Quinolines/pharmacology , Receptor, Macrophage Colony-Stimulating Factor/antagonists & inhibitors , Animals , Binding Sites , Cell Line , Drug Evaluation, Preclinical , Drug Stability , Inhibitory Concentration 50 , Models, Animal , Models, Molecular , Molecular Structure , Quinolines/chemistry , Rats , Structure-Activity RelationshipABSTRACT
We report a systematic analysis of the P1' and P2' substrate specificity of TNF-alpha converting enzyme (TACE) using a peptide library and a novel analytical method, and we use the substrate specificity information to design novel reverse hydroxamate inhibitors. Initial truncation studies, using the amino acid sequence around the cleavage site in precursor-TNF-alpha, showed that good turnover was obtained with the peptide DNP-LAQAVRSS-NH2. Based on this result, 1000 different peptide substrates of the form Biotin-LAQA-P1'-P2'-SSK(DNP)-NH2 were prepared, with 50 different natural and unnatural amino acids at P1' in combination with 20 different amino acids at P2'. The peptides were pooled, treated with purified microsomal TACE, and the reaction mixtures were passed over a streptavidin affinity column to remove unreacted substrate and the N-terminal biotinylated product. C-terminal cleavage products not binding to streptavidin were subjected to liquid chromatography/mass spectrometry analysis where individual products were identified and semiquantitated. 25 of the substrates were resynthesized as discrete peptides and assayed with recombinant TACE. The experiments show that recombinant TACE prefers lipophilic amino acids at the P1' position, such as phenylglycine, homophenylalanine, leucine and valine. At the P2' position, TACE can accommodate basic amino acids, such as arginine and lysine, as well as certain non-basic amino acids such as citrulline, methionine sulfoxide and threonine. These substrate preferences were used in the design of novel reverse hydroxamate TACE inhibitors with phenethyl and 5-methyl-thiophene-methyl side-chains at P1', and threonine and nitro-arginine at P2'.
Subject(s)
Drug Evaluation, Preclinical/methods , Metalloendopeptidases/antagonists & inhibitors , Metalloendopeptidases/metabolism , Protease Inhibitors/chemistry , Protease Inhibitors/pharmacology , Protein Interaction Mapping/methods , ADAM Proteins , ADAM17 Protein , Binding Sites , Biotin/chemistry , Chromatography, Liquid/methods , Drug Design , Image Processing, Computer-Assisted , Mass Spectrometry/methods , Metalloendopeptidases/genetics , Models, Molecular , Peptide Library , Peptides/chemistry , Peptides/pharmacology , Protein Conformation , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Structure-Activity Relationship , Substrate Specificity , Tumor Necrosis Factor-alpha/metabolismABSTRACT
The synthesis of a novel series of 3-phenylprop-2-ynylamines as selective mammalian squalene epoxidase inhibitors is described. Structure activity relationship studies led to the discovery of compound 19, 1-[3-(3,5-dichlorophenyl)-prop-2-ynyl]-3- methylpiperidine hydrochloride with an IC50 of 2.8 +/- 0.6 microM against rat liver squalene epoxidase. Against 23 strains of fungal squalene epoxidase compound 19 was found to be inactive.
Subject(s)
Amines/chemistry , Amines/pharmacology , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Oxygenases/antagonists & inhibitors , Amines/chemical synthesis , Animals , Benzene Derivatives/chemistry , Benzene Derivatives/pharmacology , Enzyme Inhibitors/chemical synthesis , Female , Inhibitory Concentration 50 , Rats , Rats, Sprague-Dawley , Squalene Monooxygenase , Structure-Activity RelationshipABSTRACT
The design of rigid cyclic analogues derived from cinnamamide 1, (E)-N-cyclopropyl-3-(3-fluorophenyl)prop-2-enamide, and beta-methylcinnamamide 2, (E)-N-cyclopropyl-3-(3-fluorophenyl)but-2-enamide, has led to the discovery of the potent, centrally acting muscle relaxant (E)-2-(4,6-difluoro-1-indanylidene)acetamide, 17. Compound 17 also possesses potent antiinflammatory and analgesic activity. This paper describes the synthesis and the muscle relaxant, antiinflammatory, and analgesic structure-activity relationships of 17 and 67 of its analogues. Compound 17 has been taken into phase I clinical trials.
Subject(s)
Acetamides/chemical synthesis , Analgesics/chemical synthesis , Anti-Inflammatory Agents, Non-Steroidal/chemical synthesis , Indans/chemical synthesis , Muscle Relaxants, Central/chemical synthesis , Acetamides/chemistry , Acetamides/pharmacology , Analgesics/chemistry , Analgesics/pharmacology , Animals , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Hypnotics and Sedatives/chemical synthesis , Hypnotics and Sedatives/chemistry , Hypnotics and Sedatives/pharmacology , Indans/chemistry , Indans/pharmacology , Mice , Monoamine Oxidase/metabolism , Monoamine Oxidase Inhibitors/chemical synthesis , Monoamine Oxidase Inhibitors/chemistry , Monoamine Oxidase Inhibitors/pharmacology , Muscle Relaxants, Central/chemistry , Muscle Relaxants, Central/pharmacology , Rats , Rats, Inbred Lew , Rats, Wistar , Stereoisomerism , Structure-Activity RelationshipABSTRACT
Extension of the structure-activity relationship studies that led to the discovery of the nonsedating potent muscle relaxant, antiinflammatory, and analgesic agent (E)-2-(4,6-difluoro-1-indanylidene)acetamide, 1, has given rise to (E)-2-(4-chloro-6-fluoro-1-indanylidene)-N-methylacetamide, 2. Compound 2 is a potent antiinflammatory and analgesic agent without centrally acting muscle relaxant activity.
