ABSTRACT
A series of novel allosteric antagonists of the GLP-1 receptor (GLP-1R), exemplified by HTL26119, are described. SBDD approaches were employed to identify HTL26119, exploiting structural understanding of the allosteric binding site of the closely related Glucagon receptor (GCGR) (Jazayeri et al., 2016) and the homology relationships between GCGR and GLP-1R. The region around residue C3476.36b of the GLP-1R receptor represents a key difference from GCGR and was targeted for selectivity for GLP-1R.
Subject(s)
Glucagon-Like Peptide-1 Receptor/antagonists & inhibitors , Heterocyclic Compounds/chemistry , Allosteric Regulation/drug effects , Allosteric Site , Amino Acid Sequence , Drug Design , Molecular Docking Simulation , Molecular Structure , Protein Binding , Receptors, Glucagon/antagonists & inhibitors , Signal Transduction , Structure-Activity RelationshipABSTRACT
UNLABELLED: Acetaminophen-induced acute liver failure (AALF) is characterized both by activation of innate immune responses and susceptibility to sepsis. Circulating monocytes and hepatic macrophages are central mediators of inflammatory responses and tissue repair processes during human AALF. Secretory leukocyte protease inhibitor (SLPI) modulates monocyte/macrophage function through inhibition of nuclear factor kappa B (NF-κB) signaling. The aims of this study were to establish the role of SLPI in AALF. Circulating levels of SLPI, monocyte cluster of differentiation 163 (CD163), human leukocyte antigen-DR (HLA-DR), and lipopolysaccharide (LPS)-stimulated levels of NF-κBp65, tumor necrosis factor alpha (TNF-α) and interleukin (IL)-6 were determined in patients with AALF, chronic liver disease, and healthy controls. Immunohistochemistry and multispectral imaging of AALF explant tissue determined the cellular sources of SLPI and hepatic macrophage phenotype. The phenotype and function of monocytes and macrophages was determined following culture with recombinant human (rh)-SLPI, liver homogenates, and plasma derived from AALF patients in the presence and absence of antihuman (α)SLPI. Hepatic and circulatory concentrations of SLPI were elevated in AALF and immunohistochemistry revealed SLPI expression in biliary epithelial cells and within hepatic macrophages (h-mψ) in areas of necrosis. H-mψ and circulating monocytes in AALF exhibited an anti-inflammatory phenotype and functional characteristics; typified by reductions in NF-κBp65, TNF-α, and IL-6 and preserved IL-10 secretion following LPS challenge. Culture of healthy monocytes with AALF liver homogenates, plasma, or rhSLPI induced monocytes with strikingly similar anti-inflammatory characteristics which were reversed by inhibiting the activity of SLPI. CONCLUSION: SLPI is a pivotal mediator of anti-inflammatory responses in AALF through modulation of monocyte/macrophage function, which may account for the susceptibility to sepsis in AALF.
Subject(s)
Acetaminophen/adverse effects , Chemical and Drug Induced Liver Injury/physiopathology , Inflammation/prevention & control , Inflammation/physiopathology , Macrophages/physiology , Monocytes/physiology , Secretory Leukocyte Peptidase Inhibitor/physiology , Adolescent , Adult , Antigens, CD/blood , Antigens, Differentiation, Myelomonocytic/blood , Case-Control Studies , Chemical and Drug Induced Liver Injury/blood , HLA-DR Antigens/blood , Humans , Inflammation/blood , Interleukin-6/blood , Middle Aged , NF-kappa B/blood , Phenotype , Receptors, Cell Surface/blood , Secretory Leukocyte Peptidase Inhibitor/blood , Signal Transduction/physiology , Tumor Necrosis Factor-alpha/blood , Young AdultABSTRACT
A series of macrocyclic calcitonin gene-related peptide (CGRP) receptor antagonists identified using structure-based design principles, exemplified by HTL0028016 (1) and HTL0028125 (2), is described. Structural characterization by X-ray crystallography of the interaction of two of the macrocycle antagonists with the CGRP receptor ectodomain is described, along with structure-activity relationships associated with point changes to the macrocyclic antagonists. The identification of non-peptidic/natural product-derived, macrocyclic ligands for a G protein coupled receptor (GPCR) is noteworthy.
Subject(s)
Receptors, Calcitonin Gene-Related Peptide , Receptors, G-Protein-Coupled , Calcitonin Receptor-Like Protein/chemistry , Calcitonin Receptor-Like Protein/metabolism , Crystallography, X-Ray , Ligands , Receptors, Calcitonin Gene-Related Peptide/chemistry , Receptors, Calcitonin Gene-Related Peptide/metabolism , Receptors, G-Protein-Coupled/metabolismABSTRACT
Inhibition of the aspartyl protease BACE-1 has the potential to deliver a disease-modifying therapy for Alzheimer's disease. Herein, is described a series of potent inhibitors based on an hydroxyethylamine (HEA) transition state mimetic template. These inhibitors interact with the non prime side of the enzyme using a novel edge-to-face interaction with Arg-296.
Subject(s)
Amyloid Precursor Protein Secretases/antagonists & inhibitors , Arginine/chemistry , Ethylamines/chemistry , Protease Inhibitors/chemistry , Alzheimer Disease/drug therapy , Amyloid Precursor Protein Secretases/chemistry , Amyloid Precursor Protein Secretases/metabolism , Animals , Binding Sites , Computer Simulation , Crystallography, X-Ray , Ethylamines/chemical synthesis , Ethylamines/therapeutic use , Protease Inhibitors/chemical synthesis , Protease Inhibitors/therapeutic use , Rats , Structure-Activity RelationshipABSTRACT
Inhibition of the aspartyl protease BACE-1 has the potential to deliver a disease-modifying therapy for Alzheimer's disease. We have recently disclosed a series of transition-state mimetic BACE-1 inhibitors showing nanomolar potency in cell-based assays. Amongst them, GSK188909 (compound 2) had favorable pharmacokinetics and was the first orally bioavailable inhibitor reported to demonstrate brain amyloid lowering in an animal model. In this Letter, we describe the reasons that led us to favor a second generation of inhibitors for further in vivo studies.
Subject(s)
Aspartic Acid Endopeptidases/antagonists & inhibitors , Protease Inhibitors/chemistry , Thiazines/chemistry , Administration, Oral , Alzheimer Disease/drug therapy , Amyloid beta-Peptides/metabolism , Animals , Aspartic Acid Endopeptidases/metabolism , Binding Sites , Computer Simulation , Ethylamines/chemical synthesis , Ethylamines/chemistry , Ethylamines/pharmacology , Humans , Mice , Protease Inhibitors/pharmacokinetics , Rats , Structure-Activity Relationship , Thiazines/chemical synthesis , Thiazines/pharmacokineticsABSTRACT
Our first generation of hydroxyethylamine transition-state mimetic BACE-1 inhibitors allowed us to validate BACE-1 as a key target for Alzheimer's disease by demonstrating amyloid lowering in an animal model, albeit at rather high doses. Finding a molecule from this series which was active at lower oral doses proved elusive and demonstrated the need to find a novel series of inhibitors with improved pharmacokinetics. This Letter describes the discovery of such inhibitors.
Subject(s)
Aspartic Acid Endopeptidases/antagonists & inhibitors , Ethylamines/chemistry , Protease Inhibitors/chemistry , Administration, Oral , Alzheimer Disease/drug therapy , Amyloid beta-Peptides/metabolism , Animals , Aspartic Acid Endopeptidases/metabolism , Binding Sites , Computer Simulation , Crystallography, X-Ray , Ethylamines/chemical synthesis , Ethylamines/pharmacology , Humans , Mice , Protease Inhibitors/chemical synthesis , Protease Inhibitors/pharmacology , Rats , Structure-Activity Relationship , Thiazines/chemistry , Thiazines/pharmacologyABSTRACT
Our first generation of hydroxyethylamine BACE-1 inhibitors proved unlikely to provide molecules that would lower amyloid in an animal model at low oral doses. This observation led us to the discovery of a second generation of inhibitors having nanomolar activity in a cell-based assay and with the potential for improved pharmacokinetic profiles. In this Letter, we describe our successful strategy for the optimization of oral bioavailability and also give insights into the design of compounds with the potential for improved brain penetration.
Subject(s)
Aspartic Acid Endopeptidases/antagonists & inhibitors , Ethylamines/chemistry , Protease Inhibitors/chemistry , ATP Binding Cassette Transporter, Subfamily B, Member 1/genetics , ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , Amyloid beta-Peptides/metabolism , Animals , Aspartic Acid Endopeptidases/metabolism , Biological Availability , Dogs , Ethylamines/chemical synthesis , Ethylamines/pharmacokinetics , Mice , Mice, Knockout , Protease Inhibitors/chemical synthesis , Protease Inhibitors/pharmacokinetics , Rats , Structure-Activity RelationshipABSTRACT
BACE-1 inhibition has the potential to provide a disease-modifying therapy for the treatment of Alzheimer's disease. Optimization of a first generation of BACE-1 inhibitors led to the discovery of novel hydroxyethylamines (HEAs) bearing a tricyclic nonprime side. These derivatives have nanomolar cell potency and are orally bioavailable.
Subject(s)
Amyloid Precursor Protein Secretases/antagonists & inhibitors , Benzothiadiazines/chemical synthesis , Cyclic S-Oxides/chemical synthesis , Ethylamines/chemical synthesis , Administration, Oral , Animals , Benzothiadiazines/pharmacokinetics , Benzothiadiazines/pharmacology , Biological Availability , Cyclic S-Oxides/pharmacokinetics , Cyclic S-Oxides/pharmacology , Dogs , Ethylamines/pharmacokinetics , Ethylamines/pharmacology , Models, Molecular , Rats , Structure-Activity RelationshipABSTRACT
Inhibition of the aspartyl protease BACE-1 has the potential to deliver a disease-modifying therapy for Alzheimer's disease. Herein, is described the lead generation effort which resulted, with the support of X-ray crystallography, in the discovery of potent inhibitors based on a hydroxy ethylamine (HEA) transition-state mimetic. These inhibitors were capable of lowering amyloid production in a cell-based assay.
Subject(s)
Alzheimer Disease/metabolism , Aspartic Acid Endopeptidases/antagonists & inhibitors , Combinatorial Chemistry Techniques , Ethylamines/chemical synthesis , Ethylamines/pharmacology , Alzheimer Disease/drug therapy , Amyloid beta-Protein Precursor/antagonists & inhibitors , Crystallography, X-Ray , Ethylamines/chemistry , Molecular Structure , Structure-Activity RelationshipABSTRACT
This article is focusing on further optimization of previously described hydroxy ethylamine (HEA) BACE-1 inhibitors obtained from a focused library with the support of X-ray crystallography. Optimization of the non-prime side of our inhibitors and introduction of a 6-membered sultam substituent binding to Asn-294 as well as a fluorine in the C-2 position led to derivatives with nanomolar potency in cell-based assays.
Subject(s)
Alzheimer Disease/metabolism , Aspartic Acid Endopeptidases/antagonists & inhibitors , Combinatorial Chemistry Techniques , Ethylamines/chemical synthesis , Ethylamines/pharmacology , Alzheimer Disease/drug therapy , Amyloid beta-Protein Precursor/antagonists & inhibitors , Animals , Asparagine/chemistry , Crystallography, X-Ray , Disease Models, Animal , Ethylamines/chemistry , Fluorine/chemistry , Mice , Molecular Structure , Nanotechnology , Structure-Activity RelationshipABSTRACT
This paper describes the discovery of non-peptidic, potent, and selective hydroxy ethylamine (HEA) inhibitors of BACE-1 by replacement of the prime side of a lead di-amide 2. Inhibitors with nanosmolar potency and high selectivity were identified. Depending on the nature of the P(1)(') and P(2)(') substituents, two different binding modes were observed in X-ray co-crystal structures.
Subject(s)
Alzheimer Disease/metabolism , Amyloid Precursor Protein Secretases/antagonists & inhibitors , Aspartic Acid Endopeptidases/antagonists & inhibitors , Combinatorial Chemistry Techniques , Ethylamines/chemical synthesis , Ethylamines/pharmacology , Alzheimer Disease/drug therapy , Amyloid beta-Protein Precursor/antagonists & inhibitors , Crystallography, X-Ray , Ethylamines/chemistry , Humans , Molecular Structure , Stereoisomerism , Structure-Activity RelationshipABSTRACT
We describe here the identification and characterization of 2 novel inhibitors of the fibroblast growth factor receptor (FGFR) family of receptor tyrosine kinases. The compounds exhibit selective inhibition of FGFR over the closely related VEGFR2 receptor in cell lines and in vivo. The pharmacologic profile of these inhibitors was defined using a panel of human tumor cell lines characterized for specific mutations, amplifications, or translocations known to activate one of the four FGFR receptor isoforms. This pharmacology defines a profile for inhibitors that are likely to be of use in clinical settings in disease types where FGFR is shown to play an important role.