ABSTRACT
GPR40/FFAR1 is a G-protein-coupled receptor expressed in pancreatic ß-cells and enteroendocrine cells. GPR40 activation stimulates secretions of insulin and incretin, both of which are the pivotal regulators of glycemic control. Therefore, a GPR40 agonist is an attractive target for the treatment of type 2 diabetes mellitus. Using the reported biaryl derivative 1, we shifted the hydrophobic moiety to the terminal aryl ring and replaced the central aryl ring with piperidine, generating 2-(4,4-dimethylpentyl)phenyl piperidine 4a, which had improved potency for GPR40 and high lipophilicity. We replaced the hydrophobic moiety with N-alkyl-N-aryl benzamides to lower the lipophilicity and restrict the N-alkyl moieties to the presumed lipophilic pocket using the intramolecular π-π stacking of cis-preferential N-alkyl-N-aryl benzamide. Among these, orally available (3S)-3-cyclopropyl-3-(2-((1-(2-((2,2-dimethylpropyl)(6-methylpyridin-2-yl)carbamoyl)-5-methoxyphenyl)piperidin-4-yl)methoxy)pyridin-4-yl)propanoic acid (SCO-267) effectively stimulated insulin secretion and GLP-1 release and ameliorated glucose tolerance in diabetic rats via GPR40 full agonism.
Subject(s)
Benzamides/therapeutic use , Diabetes Mellitus, Experimental/drug therapy , Hypoglycemic Agents/therapeutic use , Piperidines/therapeutic use , Receptors, G-Protein-Coupled/agonists , Animals , Benzamides/chemical synthesis , Benzamides/pharmacokinetics , CHO Cells , Cricetulus , Hypoglycemic Agents/chemical synthesis , Hypoglycemic Agents/pharmacokinetics , Male , Mice, Inbred ICR , Molecular Structure , Piperidines/chemical synthesis , Piperidines/pharmacokinetics , Rats, Sprague-Dawley , Structure-Activity RelationshipABSTRACT
We investigated the gastrointestinal absorption characteristics of oral sustained-release formulations in microminipigs, dogs, and monkeys in order to clarify the similarities in absorption properties between these animals and humans. Time profiles of oral absorption of nifedipine and valproic acid were calculated from the plasma concentration-time profiles of the drugs by a deconvolution method. The curves for both drugs in microminipigs were close to or slightly higher than those in humans, whereas those in monkeys were lower. Furthermore, the plasma concentration-time profiles of the drugs were subjected to non-compartmental analysis. The fractions of a dose absorbed into the portal vein (FaFg) in microminipigs ranged from 50 to 100% of the human values, whereas those in monkeys were less than half the human values. In addition, the other absorption-related parameters for the sustained-release formulation in microminipigs, as well as monkeys, were comparable to those in humans. In conclusion, the oral absorption properties of microminipigs and humans were similar regarding the sustained-release formulations. Therefore, microminipig is a suitable animal model to estimate the oral absorption of sustained-release formulations in humans.
Subject(s)
Delayed-Action Preparations/pharmacokinetics , Intestinal Absorption , Models, Animal , Swine, Miniature , Administration, Intravenous , Administration, Oral , Animals , Delayed-Action Preparations/administration & dosage , Dogs , Humans , Macaca fascicularis , Male , Nifedipine/administration & dosage , Nifedipine/blood , Nifedipine/pharmacokinetics , Swine , Valproic Acid/administration & dosage , Valproic Acid/blood , Valproic Acid/pharmacokineticsABSTRACT
Intracellular DNA triggers interferon release during the innate immune response. Cyclic GMP-AMP synthase (cGAS) senses intracellular double-stranded DNA not only in response to viral infection but also under autoimmune conditions. Measuring the levels of cyclic GMP-AMP (cGAMP) as a second messenger of cGAS activation is important to elucidate the physiological and pathological roles of cGAS. Therefore, we generated monoclonal antibodies against cGAMP using hybridoma technology to test antibody specificity and establish methods to detect intracellular cGAMP. The resulting cGAMP-specific antibody enabled the development of a time-resolved fluorescence energy transfer assay with a quantifiable range of 0.1 nM to 100 nM cGAMP. Using this assay, we detected cellular and tissue cGAMP. We confirmed that the cGAMP antibody successfully targeted intracellular cGAMP through immunocytochemical analyses. These results demonstrated that the cGAMP antibody is a powerful tool that allows determining cGAS involvement in autoimmunity and disease pathology at the cell and tissue levels.
Subject(s)
Antibodies, Monoclonal/immunology , Autoimmune Diseases of the Nervous System/metabolism , Fluorescence Resonance Energy Transfer , Immunohistochemistry , Neoplasms/metabolism , Nervous System Malformations/metabolism , Nucleotides, Cyclic/metabolism , Nucleotidyltransferases/metabolism , Animals , Antibody Specificity , Autoimmune Diseases of the Nervous System/genetics , Autoimmune Diseases of the Nervous System/immunology , Autoimmunity , Biomarkers/metabolism , Caco-2 Cells , Disease Models, Animal , Enzyme Activation , Exodeoxyribonucleases/deficiency , Exodeoxyribonucleases/genetics , HEK293 Cells , HL-60 Cells , High-Throughput Screening Assays , Humans , Mice, Inbred C57BL , Mice, Knockout , Neoplasms/immunology , Nervous System Malformations/genetics , Nervous System Malformations/immunology , Nucleotides, Cyclic/immunology , Nucleotidyltransferases/genetics , Phosphoproteins/deficiency , Phosphoproteins/genetics , Predictive Value of Tests , Reproducibility of ResultsABSTRACT
PURPOSE: Intranasal administration enhances drug delivery to the brain by allowing targeted-drug delivery. Here, we investigated the properties that render a compound suitable for intranasal administration, and the differences between rodents and non-human primates in delivery to the brain. METHODS: The delivery of 10 low-permeable compounds to the brain, including substrates of efflux drug transporters expressed in the blood-brain barrier (didanosine, metformin, zolmitriptan, cimetidine, methotrexate, talinolol, ranitidine, atenolol, furosemide, and sulpiride) and two high-permeable compounds (ropinirole and midazolam) was evaluated following intranasal and intravenous administration in rats. Six of the 12 compounds (metformin, cimetidine, methotrexate, talinolol, sulpiride, and ropinirole) were also evaluated in monkeys, which have a similar nasal cavity anatomical structure to humans. RESULTS: In rats, most of the low-permeable compounds displayed an obvious increase in the brain/plasma concentration ratio (Kp) by intranasal administration (despite their substrate liability for efflux drug transporters); this was not observed with the high-permeable compounds. Similarly, intranasal administration increased Kp for all low-permeable compounds in monkeys. CONCLUSIONS: Compound permeability is a key determinant of Kp increase by intranasal administration. This route of administration is more beneficial for low-permeable compounds and enhances their delivery to the brain in rodents and non-human primates.
Subject(s)
Blood-Brain Barrier/metabolism , Brain/metabolism , Drug Delivery Systems/methods , Pharmaceutical Preparations/administration & dosage , Administration, Intranasal , Animals , Macaca fascicularis , Male , Membranes, Artificial , Olfactory Bulb/metabolism , Permeability , Pharmacokinetics , Rats , Rats, Sprague-DawleyABSTRACT
G-protein-coupled receptor 52 (GPR52) is classified as an orphan Gs-coupled G-protein-coupled receptor. GPR52 cancels dopamine D2 receptor signaling and activates dopamine D1/N-methyl-d-aspartate receptors via intracellular cAMP accumulation. Therefore, GPR52 agonists are expected to alleviate symptoms of psychotic disorders. A novel series of 1-(benzothiophen-7-yl)-1H-pyrazole as GPR52 agonists was designed and synthesized based on compound 1b. Compound 1b has been reported by our group as the first orally active GPR52 agonist, but high lipophilicity and poor aqueous solubility still remained as issues for candidate selection. To resolve these issues, replacement of the benzene ring at the 7-positon of compound 1b with heterocylic rings, such as pyrazole and pyridine, was greatly expected to reduce lipophilicity to levels for which calculated logD values were lower than that of compound 1b. While evaluating the pyrazole derivatives, introduction of a methyl substituent at the 3-position of the pyrazole ring led to increased GPR52 agonistic activity. Moreover, additional methyl substituent at the 5-position of the pyrazole and further introduction of hydroxy group to lower logD led to significant improvement of solubility while maintaining the activity. As a result, we identified 3-methyl-5-hydroxymethyl-1H-pyrazole derivative 17 (GPR52 EC50â¯=â¯21â¯nM, Emaxâ¯=â¯103%, logDâ¯=â¯2.21, Solubility at pH 6.8â¯=â¯21⯵g/mL) with potent GPR52 agonistic activity and good solubility compared to compound 1b. Furthermore, this compound 17 dose-dependently suppressed methamphetamine-induced hyperlocomotion in mice.
Subject(s)
Pyrazoles/pharmacology , Receptors, G-Protein-Coupled/agonists , Thiophenes/pharmacology , Animals , Dose-Response Relationship, Drug , Drug Design , Humans , Locomotion/drug effects , Male , Methamphetamine , Mice , Mice, Inbred ICR , Molecular Structure , Pyrazoles/chemical synthesis , Pyrazoles/chemistry , Structure-Activity Relationship , Thiophenes/chemical synthesis , Thiophenes/chemistryABSTRACT
We identified novel potent inhibitors of p38 MAP kinase using structure-based design strategy. X-ray crystallography showed that when p38 MAP kinase is complexed with TAK-715 (1) in a co-crystal structure, Phe169 adopts two conformations, where one interacts with 1 and the other shows no interaction with 1. Our structure-based design strategy shows that these two conformations converge into one via enhanced protein-ligand hydrophobic interactions. According to the strategy, we focused on scaffold transformation to identify imidazo[1,2-b]pyridazine derivatives as potent inhibitors of p38 MAP kinase. Among the herein described and evaluated compounds, N-oxide 16 exhibited potent inhibition of p38 MAP kinase and LPS-induced TNF-α production in human monocytic THP-1 cells, and significant in vivo efficacy in rat collagen-induced arthritis models. In this article, we report the discovery of potent, selective and orally bioavailable imidazo[1,2-b]pyridazine-based p38 MAP kinase inhibitors with pyridine N-oxide group.
Subject(s)
Drug Design , Protein Kinase Inhibitors/chemical synthesis , Pyridazines/chemistry , p38 Mitogen-Activated Protein Kinases/antagonists & inhibitors , Animals , Anti-Inflammatory Agents/chemical synthesis , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Arthritis/drug therapy , Arthritis/etiology , Cell Line , Disease Models, Animal , Enzyme Activation/drug effects , Female , Humans , Molecular Dynamics Simulation , Monocytes/cytology , Monocytes/drug effects , Monocytes/metabolism , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/therapeutic use , Protein Structure, Tertiary , Pyridazines/pharmacology , Pyridazines/therapeutic use , Rats , Rats, Inbred Lew , Structure-Activity Relationship , Tumor Necrosis Factor-alpha/metabolism , p38 Mitogen-Activated Protein Kinases/metabolismABSTRACT
In addition to their potent antidiabetic effects, glucagon-like peptide-1 (GLP-1) analogs lower body weight in humans. Hence, agonistic targeting of the GLP-1 receptor could be a valid approach to target obesity. However, quantitative analyses of the pharmacokinetic/pharmacodynamic (PK/PD) relationship between GLP-1 analogs and their antiobesity effect have not been reported in either animals or humans. Therefore, the present study was performed to establish a mechanism-based PK/PD model of GLP-1 receptor agonists using the GLP-1 analog exenatide for the development of promising new antiobesity drugs. Exenatide was administered to high-fat diet-induced obese C57BL/6J mice via subcutaneous bolus and continuous infusion. Food intake and body-weight reductions were observed and depended on the plasma concentrations of exenatide. The homeostatic feedback model, in which food intake is assumed to be regulated by appetite control signals, described the relationship among the plasma concentration-time profile of exenatide, food intake, and body weight. The estimated IC50 of exenatide against food intake was 2.05 pM, which is similar to the reported KD value of exenatide in rat brain and the estimated EC50 value for augmentation of insulin secretion in humans. The PK/PD model simulation indicated that subcutaneous infusion would show a stronger effect on body-weight reduction than bolus dosing would. This novel, quantitative PK/PD model could be used for antiobesity research and development of GLP-1 analogs, GLP-1 secretagogues, GLP-1 degradation inhibitors, and combinations thereof by allowing the estimation of appropriate pharmacokinetic profiles and dosing regimens.
Subject(s)
Anti-Obesity Agents , Glucagon-Like Peptide-1 Receptor/agonists , Models, Biological , Obesity/drug therapy , Peptides , Venoms , Animals , Anti-Obesity Agents/pharmacokinetics , Anti-Obesity Agents/pharmacology , Anti-Obesity Agents/therapeutic use , Body Weight/drug effects , Diet, High-Fat , Exenatide , Infusions, Subcutaneous , Injections, Subcutaneous , Male , Mice, Inbred C57BL , Obesity/metabolism , Peptides/pharmacokinetics , Peptides/pharmacology , Peptides/therapeutic use , Venoms/pharmacokinetics , Venoms/pharmacology , Venoms/therapeutic useABSTRACT
With the aim to find a novel long-lasting potassium-competitive acid blocker (P-CAB) that would perfectly overcome the limitations of proton pump inhibitors (PPIs), we tried various approaches based on pyrrole derivative 1b as a lead compound. As part of a comprehensive approach to identification of a new drug, we explored excellent compounds that have low lipophilicity by introducing a polar hetero-aromatic group at position 5 of the pyrrole ring. Among the compounds synthesized, fluoropyrrole derivative 37c, which has a 2-F-3-Py group at the fifth position, lower pKa, and much lower ClogP and logD values than 1b dose, showed potent gastric-acid suppressive action resulting from gastric H+,K+-ATPase inhibition in animal models. Its maximum intragastric pH elevation effect was strong in rats, and its duration of action was much longer than that of either lansoprazole or lead compound 1b in dogs. Therefore, compound 37c can be considered a promising new P-CAB with long duration of action.
Subject(s)
Ether-A-Go-Go Potassium Channels/antagonists & inhibitors , Gastric Acid/metabolism , H(+)-K(+)-Exchanging ATPase/metabolism , Proton Pump Inhibitors/pharmacology , Pyrroles/pharmacology , Administration, Oral , Animals , Cell Survival/drug effects , Dogs , Dose-Response Relationship, Drug , Ether-A-Go-Go Potassium Channels/metabolism , HEK293 Cells , Hep G2 Cells , Humans , Hydrogen-Ion Concentration , Molecular Structure , Proton Pump Inhibitors/administration & dosage , Proton Pump Inhibitors/chemistry , Pyrroles/administration & dosage , Pyrroles/chemistry , Rats , Structure-Activity RelationshipABSTRACT
Centrally acting noradrenaline reuptake inhibitor (NRI) is reportedly effective for patients with stress urinary incontinence (SUI) by increasing urethral closure in the clinical Phase IIa study with esreboxetine. Noradrenaline transporters are expressed in both central and peripheral nervous systems and the contribution of each site to efficacy has not been clarified. This report describes the development of a series of peripheral-selective 7-phenyl-1,4-oxazepane NRIs to investigate the contribution of the peripheral site to increasing urethral resistance in rats. (6S,7R)-1,4-Oxazepane derivative 7 exhibited noradrenaline transporter inhibition with high selectivity against inhibitions of serotonin and dopamine transporters. A replacement of hydroxyl with acetamide group contributed to enhancement of peripheral selectivity by increasing molecular polarity. Compound 12, N-{[(6S,7R)-7-(3,4-dichlorophenyl)-1,4-oxazepan-6-yl]methyl}acetamide 0.5 fumarate, which showed effectively no brain penetration in rats, increased urethral resistance in a dose-dependent manner and exhibited a maximal effect on par with esreboxetine. These results demonstrate that the urethral resistance-increasing effects of NRI in rats are mainly caused by the inhibition of noradrenaline transporters in the peripheral sites.
Subject(s)
Drug Design , Heterocyclic Compounds/chemistry , Serotonin and Noradrenaline Reuptake Inhibitors/chemical synthesis , Animals , Cerebral Cortex/metabolism , Dopamine Plasma Membrane Transport Proteins/chemistry , Dopamine Plasma Membrane Transport Proteins/metabolism , Female , Heterocyclic Compounds/chemical synthesis , Heterocyclic Compounds/therapeutic use , Humans , Molecular Conformation , Morpholines/therapeutic use , Norepinephrine Plasma Membrane Transport Proteins/chemistry , Norepinephrine Plasma Membrane Transport Proteins/metabolism , Rats , Rats, Sprague-Dawley , Serotonin Plasma Membrane Transport Proteins/chemistry , Serotonin Plasma Membrane Transport Proteins/metabolism , Serotonin and Noradrenaline Reuptake Inhibitors/chemistry , Serotonin and Noradrenaline Reuptake Inhibitors/therapeutic use , Stereoisomerism , Structure-Activity Relationship , Urinary Incontinence, Stress/drug therapyABSTRACT
G-protein-coupled receptor 52 (GPR52) is an orphan Gs-coupled G-protein-coupled receptor. GPR52 inhibits dopamine D2 receptor signaling and activates dopamine D1/N-methyl-d-aspartate receptors via intracellular cAMP accumulation, and therefore, GPR52 agonists may have potential as a novel class of antipsychotics. A series of GPR52 agonists with a bicyclic core was designed to fix the conformation of the phenethyl ether moiety of compounds 2a and 2b. 3-[2-(3-Chloro-5-fluorobenzyl)-1-benzothiophen-7-yl]-N-(2-methoxyethyl)benzamide 7m showed potent activity (pEC50 = 7.53 ± 0.08) and good pharmacokinetic properties. Compound 7m significantly suppressed methamphetamine-induced hyperactivity in mice after oral administration of 3 mg/kg without disturbance of motor function.
Subject(s)
Antipsychotic Agents/chemical synthesis , Benzamides/chemical synthesis , Receptors, G-Protein-Coupled/agonists , Thiophenes/chemical synthesis , Administration, Oral , Animals , Antipsychotic Agents/pharmacokinetics , Antipsychotic Agents/pharmacology , Benzamides/pharmacokinetics , Benzamides/pharmacology , Brain/metabolism , CHO Cells , Cricetulus , Humans , Male , Methamphetamine/pharmacology , Mice, Inbred ICR , Models, Molecular , Motor Activity/drug effects , Structure-Activity Relationship , Thiophenes/pharmacokinetics , Thiophenes/pharmacologyABSTRACT
We recently reported the discovery of octahydropyrrolo[1,2-a]pyrazine A as a lead compound for an inhibitor of apoptosis proteins (IAP) antagonist. To develop IAP antagonists with favorable PK profiles, we designed novel tri-cyclic compounds, octahydro-1H-cyclopropa[4,5]pyrrolo[1,2-a]pyrazines 1 and 2 based on co-crystal structural analysis of A with cellular IAP-1 (cIAP-1). The additional cyclopropane moiety was used to block the predicted metabolic site of compound A without detriment to the binding affinity for cIAP. Compounds 1 and 2 were stereoselectively synthesized via intermediates 4a and 5b', which were obtained by Simmons-Smith cyclopropanation of ethylester 3a and silyl ether 3b'. Compounds 1 and 2 showed strong growth inhibition in MDA-MB-231 breast cancer cells and improved metabolic stability in comparison to A. Compound 2 exhibited significant in vivo PD effects to increase tumor necrosis factor-alpha mRNA in a dose dependent manner.
Subject(s)
Drug Design , Inhibitor of Apoptosis Proteins/antagonists & inhibitors , Pyrazines/chemistry , Pyrroles/chemical synthesis , Animals , Benzopyrans/chemical synthesis , Benzopyrans/pharmacokinetics , Benzopyrans/therapeutic use , Binding Sites , Breast Neoplasms/drug therapy , Cell Line, Tumor , Crystallography, X-Ray , Female , Half-Life , Humans , Inhibitor of Apoptosis Proteins/metabolism , Mice , Molecular Dynamics Simulation , Protein Structure, Tertiary , Pyrazines/chemical synthesis , Pyrazines/pharmacokinetics , Pyrazines/therapeutic use , Pyrroles/chemistry , Pyrroles/pharmacokinetics , Pyrroles/therapeutic use , RNA, Messenger/metabolism , Stereoisomerism , Transplantation, Heterologous , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/metabolismABSTRACT
In our pursuit of developing a novel and potent potassium-competitive acid blocker (P-CAB), we synthesized pyrrole derivatives focusing on compounds with low log D and high ligand-lipophilicity efficiency (LLE) values. Among the compounds synthesized, the compound 13e exhibited potent H(+),K(+)-ATPase inhibitory activity and potent gastric acid secretion inhibitory action in vivo. Its maximum efficacy was more potent and its duration of action was much longer than those of proton pump inhibitors (PPIs). Therefore, compound 13e (1-[5-(2-fluorophenyl)-1-(pyridin-3-ylsulfonyl)-1H-pyrrol-3-yl]-N-methylmethanamine fumarate, TAK-438) was selected as a drug candidate for the treatment of gastroesophageal reflux disease (GERD), peptic ulcer, and other acid-related diseases.