Publications by authors named "Gerald E Hunsberger"

8 Publications

  • Page 1 of 1

Pharmacological properties of revefenacin (TD-4208), a novel, nebulized long-acting, and lung selective muscarinic antagonist, at human recombinant muscarinic receptors and in rat, guinea pig, and human isolated airway tissues.

Pharmacol Res Perspect 2018 06 30;6(3):e00400. Epub 2018 Apr 30.

Theravance Biopharma U.S, Inc South San Francisco CA USA.

Revefenacin (TD-4208) is a novel, long-acting, and lung-selective muscarinic cholinergic receptor (mAChR) antagonist in development as a nebulized inhalation solution for the treatment of chronic obstructive pulmonary disease (COPD) patients. This study evaluated the pharmacology of revefenacin at human recombinant mAChRs and in airway tissues from rats, guinea pigs, and humans. At human recombinant mAChRs, revefenacin displayed high affinity (pK = 8.2-9.8) and behaved as a competitive antagonist (pKI, apparent = 9.4-10.9) at the five human recombinant mAChRs. Kinetic studies demonstrated that revefenacin dissociated significantly slower from the hM ( = 82 minutes) compared to the hM ( = 6.9 minutes) mAChR at 37°C, thereby making it kinetically selective for the former subtype. Similarly, in functional studies, revefenacin-mediated antagonism of acetylcholine (ACh)-evoked calcium mobilization responses were reversed less rapidly at hM compared to the hM mAChR. In isolated tracheal tissues from rat and guinea pig and isolated bronchial tissues from humans, revefenacin potently antagonized mAChR-mediated contractile responses. Furthermore, the antagonistic effects of revefenacin in rat, guinea pig, and human airway tissues were slowly reversible ( of 13.3, >16, and >10 hours, respectively). These data demonstrate that revefenacin is a potent, high affinity, and selective functional mAChR antagonist with kinetic selectivity for the hM receptor and produces potent and long-lasting antagonism of mAChR-mediated contractile responses in rat, guinea pig, and human airway tissue. These data suggest that revefenacin has the potential to be a potent once-daily dosed inhaled bronchodilator in COPD patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/prp2.400DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5927803PMC
June 2018

Danirixin: A Reversible and Selective Antagonist of the CXC Chemokine Receptor 2.

J Pharmacol Exp Ther 2017 08 13;362(2):338-346. Epub 2017 Jun 13.

GSK R&D, King of Prussia PA

CXC chemokine receptor 2 (CXCR2) is a key receptor in the chemotaxis of neutrophils to sites of inflammation. The studies reported here describe the pharmacological characterization of danirixin, a CXCR2 antagonist in the diaryl urea chemical class. Danirixin has high affinity for CXCR2, with a negative log of the 50% inhibitory concentration (pIC) of 7.9 for binding to Chinese hamster ovary cell (CHO)-expressed human CXCR2, and 78-fold selectivity over binding to CHO-expressed CXCR1. Danirixin is a competitive antagonist against CXCL8 in Ca-mobilization assays, with a K (the concentration of antagonist that binds 50% of the receptor population) of 6.5 nM and antagonist potency (pA) of 8.44, and is fully reversible in washout experiments over 180 minutes. In rat and human whole-blood studies assessing neutrophil activation by surface CD11b expression following CXCL2 (rat) or CXCL1 (human) challenge, danirixin blocks the CD11b upregulation with pICs of 6.05 and 6.3, respectively. Danirixin dosed orally also blocked the influx of neutrophils into the lung in vivo in rats following aerosol lipopolysaccharide or ozone challenge, with median effective doses (EDs) of 1.4 and 16 mg/kg respectively. Thus, danirixin would be expected to block chemotaxis in disease states in which neutrophils are increased in response to inflammation, such as pulmonary diseases. In comparison with navarixin, a CXCR2 antagonist from a different chemical class, the binding characterization of danirixin is distinct. These observations may offer insight into the previously observed clinical differences in induction of neutropenia between these compounds.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1124/jpet.117.240705DOI Listing
August 2017

Transient receptor potential vanilloid 4 activation constricts the human bronchus via the release of cysteinyl leukotrienes.

J Pharmacol Exp Ther 2014 Apr 6;349(1):118-25. Epub 2014 Feb 6.

Respiratory Therapy Area, GlaxoSmithKline Pharmaceuticals, King of Prussia, Pennsylvania (M.A.M., M.A.L., G.E.H.); and Johns Hopkins Medical Institutions, Johns Hopkins University, Baltimore, Maryland (B.J.U.).

Prior studies have demonstrated that the ion channel transient receptor potential vanilloid 4 (TRPV4) is functionally expressed in airway smooth muscle cells and that TRPV4 single nucleotide polymorphisms are associated with airflow obstruction in patients with chronic obstructive pulmonary disease. We sought to use isometric tension measurements in ex vivo airways to determine whether short-term pharmacological activation of TRPV4 with the potent agonist GSK1016790 [N-((1S)-1-{[4-((2S)-2-{[(2,4-dichlorophenyl)sulfonyl]amino}-3-hydroxypropanoyl)-1-piperazinyl]carbonyl}-3-methylbutyl)-1-benzothiophene-2-carboxamide] would constrict human bronchial tissue. As predicted, transient receptor potential vanilloid 4 activation in the human airway produces contractions that are blocked by the nonselective transient receptor potential channel blocker ruthenium red. Moreover, the novel TRPV4-selective blocker GSK2334775 [(R)-6-(methylsulfonyl)-3-((4-(pyrrolidin-1-yl)piperindin-1-yl)methyl)-N-(2,2,2,-trifluoro-1-phenylethyl)-2-(3-(trifluoromethyl)phenyl)quinoline-4-carboxamide] inhibited these contractions over a concentration range consistent with its in vitro potency against recombinant and native TRPV4-containing channels. Surprisingly, TRPV4-dependent contractions were also blocked by a 5-lipoxygenase inhibitor and two structurally distinct cysteinyl leukotriene 1 receptor antagonists. In aggregate, our results fail to support the hypothesis that TRPV4 in airway smooth muscle cells regulates airway contractility short term. Rather, we provide pharmacological evidence that TRPV4 activation causes human airway constriction that is entirely dependent upon the production of cysteinyl leukotrienes. Together, these data identify a novel mechanism by which TRPV4 activation may contribute to pathologic remodeling and inflammation, in addition to airflow obstruction, in the diseased human respiratory tract.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1124/jpet.113.210203DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3965887PMC
April 2014

Design, synthesis and structure-activity relationship of N-substituted tropane muscarinic acetylcholine receptor antagonists.

Bioorg Med Chem Lett 2012 May 15;22(9):3366-9. Epub 2012 Feb 15.

GlaxoSmithKline, 709 Swedeland Road, King of Prussia, PA 19406, USA.

A novel series of N-substituted tropane derivatives was characterized as potent muscarinic acetylcholine receptor antagonists (mAChRs). Kinetic washout studies showed that the N-endosubstituted analog 24 displayed much slower reversibility at mAChRs than the methyl-substituted parent molecule darotropium. In addition, it was shown that this characteristic appeared to translate into enhanced which duration of action in a mouse model of bronchonstriction.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bmcl.2012.02.015DOI Listing
May 2012

Optimized procedures for producing biologically active chemokines.

Protein Expr Purif 2009 Jun;65(2):251-60

GlaxoSmithKline, Biological Reagents & Assay Development, Mail Code: UE0548, 709 Swedeland Road, King of Prussia, PA 19406, USA.

We describe here two strategies to produce biologically active chemokines with authentic N-terminal amino acid residues. The first involves producing the target chemokine with an N-terminal 6xHis-SUMO tag in Escherichia coli as inclusion bodies. The fusion protein is solubilized and purified with Ni-NTA-agarose in denaturing reagents. This is further followed by tag removal and refolding in a redox refolding buffer. The second approach involves expressing the target chemokine with an N-terminal 6xHis-Trx-SUMO tag in an engineered E. coli strain that facilitates formation of disulfide bonds in the cytoplasm. Following purification of the fusion protein via Ni-NTA and tag removal, the target chemokine is refolded without redox buffer and purified by reverse phase chromatography. Using the procedures, we have produced more than 15 biologically active chemokines, with a yield of up to 15 mg/L.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.pep.2009.01.017DOI Listing
June 2009

Camphor sulfonamide derivatives as novel, potent and selective CXCR3 antagonists.

Bioorg Med Chem Lett 2009 Jan 6;19(1):114-8. Epub 2008 Nov 6.

Center of Excellence for Drug Discovery, GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, PA 19426, USA.

A series of N-arylpiperazine camphor sulfonamides was discovered as novel CXCR3 antagonists. The synthesis, structure-activity relationships, and optimization of the initial hit that resulted in the identification of potent and selective CXCR3 antagonists are described.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bmcl.2008.11.008DOI Listing
January 2009

3-Arylamino-2H-1,2,4-benzothiadiazin-5-ol 1,1-dioxides as novel and selective CXCR2 antagonists.

Bioorg Med Chem Lett 2007 Jul 10;17(14):3864-7. Epub 2007 May 10.

Discovery Medicinal Chemistry, Molecular Discovery Research, GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, PA 19426, USA.

A series of 3-arylamino-2H-1,2,4-benzothiadiazin-5-ol 1,1-dioxides were prepared and shown to be novel and selective antagonists of the CXCR2 receptor. Synthesis, structure and activity relationships, selectivity, and some developability properties are described.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bmcl.2007.05.011DOI Listing
July 2007

Dendroaspis natriuretic peptide binds to the natriuretic peptide clearance receptor.

Biochem Biophys Res Commun 2007 Jun 19;358(1):145-9. Epub 2007 Apr 19.

Vascular Biology and Thrombosis Department, Cardiovascular and Urogenital Center for Excellence in Drug Discovery, GlaxoSmithKline, King of Prussia, PA 19406, USA.

Dendroaspis natriuretic peptide (DNP) is a newly-described natriuretic peptide which lowers blood pressure via vasodilation. The natriuretic peptide clearance receptor (NPR-C) removes natriuretic peptides from the circulation, but whether DNP interacts with human NPR-C directly is unknown. The purpose of this study was to test the hypothesis that DNP binds to NPR-C. ANP, BNP, CNP, and the NPR-C ligands AP-811 and cANP(4-23) displaced [(125)I]-ANP from NPR-C with pM-to-nM K(i) values. DNP displaced [(125)I]-ANP from NPR-C with nM potency, which represents the first direct demonstration of binding of DNP to human NPR-C. DNP showed high pM affinity for the GC-A receptor and no affinity for GC-B (K(i)>1000 nM). DNP was nearly 10-fold more potent than ANP at stimulating cGMP production in GC-A expressing cells. Blockade of NPR-C might represent a novel therapeutic approach in augmenting the known beneficial actions of DNP in cardiovascular diseases such as hypertension and heart failure.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bbrc.2007.04.079DOI Listing
June 2007