Publications by authors named "Vincent Mikol"

17 Publications

  • Page 1 of 1

A 3D Human Liver Model of Nonalcoholic Steatohepatitis.

J Clin Transl Hepatol 2020 Dec 15;8(4):359-370. Epub 2020 Dec 15.

Translational Sciences, Sanofi, 1 Avenue Pierre Brossolette, Chilly-Mazarin, France.

To better understand nonalcoholic steatohepatitis (NASH) disease progression and to evaluate drug targets and compound activity, we undertook the development of an 3D model to mimic liver architecture and the NASH environment. We have developed an preclinical 3D NASH model by coculturing primary human hepatocytes, human stellate cells, liver endothelial cells and Kupffer cells embedded in a hydrogel of rat collagen on a 96-well plate. A NASH-like environment was induced by addition of medium containing free fatty acids and tumor necrosis factor-α. This model was then characterized by biochemical, imaging and transcriptomics analyses. We succeeded in defining suitable culture conditions to maintain the 3D coculture for up to 10 days , with the lowest level of steatosis and reproducible low level of inflammation and fibrosis. NASH disease was induced with a custom medium mimicking NASH features. The cell model exhibited the key NASH disease phenotypes of hepatocyte injury, steatosis, inflammation, and fibrosis. Hepatocyte injury was highlighted by a decrease of CYP3A4 expression and activity, without loss of viability up to day 10. Moreover, the model was able to stimulate a stable inflammatory and early fibrotic environment, with expression and secretion of several cytokines. A global gene expression analysis confirmed the NASH induction. This is a new model of NASH disease consisting of four human primary cell-types that exhibits most features of the disease. The 10-day cell viability and cost effectiveness of the model make it suitable for medium throughput drug screening and provide attractive avenues to better understand disease physiology and to identify and characterize new drug targets.
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http://dx.doi.org/10.14218/JCTH.2020.00015DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7782122PMC
December 2020

ABHD11, a new diacylglycerol lipase involved in weight gain regulation.

PLoS One 2020 24;15(6):e0234780. Epub 2020 Jun 24.

Sanofi Research and Development, Chilly-Mazarin, France.

Obesity epidemic continues to spread and obesity rates are increasing in the world. In addition to public health effort to reduce obesity, there is a need to better understand the underlying biology to enable more effective treatment and the discovery of new pharmacological agents. Abhydrolase domain-containing protein 11 (ABHD11) is a serine hydrolase enzyme, localized in mitochondria, that can synthesize the endocannabinoid 2-arachidonoyl glycerol (2AG) in vitro. In vivo preclinical studies demonstrated that knock-out ABHD11 mice have a similar 2AG level as WT mice and exhibit a lean metabolic phenotype. Such mice resist to weight gain in Diet Induced Obesity studies (DIO) and display normal biochemical plasma parameters. Metabolic and transcriptomic analyses on serum and tissues of ABHD11 KO mice from DIO studies show a modulation in bile salts associated with reduced fat intestinal absorption. These data suggest that modulating ABHD11 signaling pathway could be of therapeutic value for the treatment of metabolic disorders.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0234780PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7313976PMC
September 2020

The RESOLUTE consortium: unlocking SLC transporters for drug discovery.

Authors:
Giulio Superti-Furga Daniel Lackner Tabea Wiedmer Alvaro Ingles-Prieto Barbara Barbosa Enrico Girardi Ulrich Goldmann Bettina Gürtl Kristaps Klavins Christoph Klimek Sabrina Lindinger Eva Liñeiro-Retes André C Müller Svenja Onstein Gregor Redinger Daniela Reil Vitaly Sedlyarov Gernot Wolf Matthew Crawford Robert Everley David Hepworth Shenping Liu Stephen Noell Mary Piotrowski Robert Stanton Hui Zhang Salvatore Corallino Andrea Faedo Maria Insidioso Giovanna Maresca Loredana Redaelli Francesca Sassone Lia Scarabottolo Michela Stucchi Paola Tarroni Sara Tremolada Helena Batoulis Andreas Becker Eckhard Bender Yung-Ning Chang Alexander Ehrmann Anke Müller-Fahrnow Vera Pütter Diana Zindel Bradford Hamilton Martin Lenter Diana Santacruz Coralie Viollet Charles Whitehurst Kai Johnsson Philipp Leippe Birgit Baumgarten Lena Chang Yvonne Ibig Martin Pfeifer Jürgen Reinhardt Julian Schönbett Paul Selzer Klaus Seuwen Charles Bettembourg Bruno Biton Jörg Czech Hélène de Foucauld Michel Didier Thomas Licher Vincent Mikol Antje Pommereau Frédéric Puech Veeranagouda Yaligara Aled Edwards Brandon J Bongers Laura H Heitman Ad P IJzerman Huub J Sijben Gerard J P van Westen Justine Grixti Douglas B Kell Farah Mughal Neil Swainston Marina Wright-Muelas Tina Bohstedt Nicola Burgess-Brown Liz Carpenter Katharina Dürr Jesper Hansen Andreea Scacioc Giulia Banci Claire Colas Daniela Digles Gerhard Ecker Barbara Füzi Viktoria Gamsjäger Melanie Grandits Riccardo Martini Florentina Troger Patrick Altermatt Cédric Doucerain Franz Dürrenberger Vania Manolova Anna-Lena Steck Hanna Sundström Maria Wilhelm Claire M Steppan

Nat Rev Drug Discov 2020 07;19(7):429-430

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http://dx.doi.org/10.1038/d41573-020-00056-6DOI Listing
July 2020

Incretin combination therapy for the treatment of non-alcoholic steatohepatitis.

Diabetes Obes Metab 2020 08 12;22(8):1328-1338. Epub 2020 Apr 12.

Sanofi Research and Development, Frankfurt, Germany.

Aims: To test specific mono-agonists to the glucagon-like peptide-1 receptor (GLP-1R), glucagon receptor (GCGR) and glucose-dependent insulinotropic peptide receptor (GIPR), individually and in combination, in a mouse model of diet-induced non-alcoholic steatohepatitis (NASH) and fibrosis in order to decipher the contribution of their activities and potential additive effects to improving systemic and hepatic metabolism.

Materials And Methods: We induced NASH by pre-feeding C57BL/6J mice a diet rich in fat, fructose and cholesterol for 36 weeks. This was followed by 8 weeks of treatment with the receptor-specific agonists 1-GCG (20 μg/kg twice daily), 2-GLP1 (3 μg/kg twice daily) or 3-GIP (30 μg/kg twice daily), or the dual (1 + 2) or triple (1 + 2 + 3) combinations thereof. A dual GLP-1R/GCGR agonistic peptide, 4-dual-GLP1/GCGR (30 μg/kg twice daily), and liraglutide (100 μg/kg twice daily) were included as references.

Results: Whereas low-dose 1-GCG or 3-GIP alone did not influence body weight, liver lipids and histology, their combination with 2-GLP1 provided additional weight loss, reduction in liver triglycerides and improvement in histological disease activity score. Notably, 4-dual-GLP-1R/GCGR and the triple combination of selective mono-agonists led to a significantly stronger reduction in the histological non-alcoholic fatty liver disease activity score compared to high-dose liraglutide, at the same extent of body weight loss.

Conclusions: GCGR and GIPR agonism provide additional, body weight-independent improvements on top of GLP-1R agonism in a murine model of manifest NASH with fibrosis.
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http://dx.doi.org/10.1111/dom.14035DOI Listing
August 2020

A single T cell epitope drives the neutralizing anti-drug antibody response to natalizumab in multiple sclerosis patients.

Nat Med 2019 09 9;25(9):1402-1407. Epub 2019 Sep 9.

Institute for Research in Biomedicine, Università della Svizzera italiana, Bellinzona, Switzerland.

Natalizumab (NZM), a humanized monoclonal IgG4 antibody to α4 integrins, is used to treat patients with relapsing-remitting multiple sclerosis (MS), but in about 6% of the cases persistent neutralizing anti-drug antibodies (ADAs) are induced leading to therapy discontinuation. To understand the basis of the ADA response and the mechanism of ADA-mediated neutralization, we performed an in-depth analysis of the B and T cell responses in two patients. By characterizing a large panel of NZM-specific monoclonal antibodies, we found that, in both patients, the response was polyclonal and targeted different epitopes of the NZM idiotype. The neutralizing activity was acquired through somatic mutations and correlated with a slow dissociation rate, a finding that was supported by structural data. Interestingly, in both patients, the analysis of the CD4 T cell response, combined with mass spectrometry-based peptidomics, revealed a single immunodominant T cell epitope spanning the FR2-CDR2 region of the NZM light chain. Moreover, a CDR2-modified version of NZM was not recognized by T cells, while retaining binding to α4 integrins. Collectively, our integrated analysis identifies the basis of T-B collaboration that leads to ADA-mediated therapeutic resistance and delineates an approach to design novel deimmunized antibodies for autoimmune disease and cancer treatment.
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http://dx.doi.org/10.1038/s41591-019-0568-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6795539PMC
September 2019

A Human Stem Cell Model of Fabry Disease Implicates LIMP-2 Accumulation in Cardiomyocyte Pathology.

Stem Cell Reports 2019 08 1;13(2):380-393. Epub 2019 Aug 1.

Sanofi, Translational Sciences Unit, Sanofi, 13 quai Jules Guesdes, 94400 Vitry-sur-Seine, France. Electronic address:

Here, we have used patient-derived induced pluripotent stem cell (iPSC) and gene-editing technology to study the cardiac-related molecular and functional consequences of mutations in GLA causing the lysosomal storage disorder Fabry disease (FD), for which heart dysfunction is a major cause of mortality. Our in vitro model recapitulated clinical data with FD cardiomyocytes accumulating GL-3 and displaying an increased excitability, with altered electrophysiology and calcium handling. Quantitative proteomics enabled the identification of >5,500 proteins in the cardiomyocyte proteome and secretome, and revealed accumulation of the lysosomal protein LIMP-2 and secretion of cathepsin F and HSPA2/HSP70-2 in FD. Genetic correction reversed these changes. Overexpression of LIMP-2 directly induced the secretion of cathepsin F and HSPA2/HSP70-2, implying causative relationship, and led to massive vacuole accumulation. In summary, our study has revealed potential new cardiac biomarkers for FD, and provides valuable mechanistic insight into the earliest pathological events in FD cardiomyocytes.
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http://dx.doi.org/10.1016/j.stemcr.2019.07.004DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6700557PMC
August 2019

Type 2/Th2-driven inflammation impairs olfactory sensory neurogenesis in mouse chronic rhinosinusitis model.

Allergy 2019 03 16;74(3):549-559. Epub 2018 Dec 16.

Translational Sciences, Sanofi, Chilly-Mazarin, France.

Background: Chronic rhinosinusitis (CRS) with nasal polyps (CRSwNP) is a chronic inflammatory disease often accompanied by impairment of sense of smell. This symptom has been somewhat overlooked, and its relationship to inflammatory cytokines, tissue compression, neuronal loss, and neurogenesis is still unclear.

Methods: In order to elucidate potential mechanisms leading to CRS in humans, we have established a type 2/T helper type 2 cell (Th2)-mediated allergic CRS mouse model, based on house dust mite (HDM) and Staphylococcus aureus enterotoxin B (SEB) sensitization. The inflammatory status of the olfactory epithelium (OE) was assessed using histology, biochemistry, and transcriptomics. The sense of smell was evaluated by studying olfactory behavior and recording electro-olfactograms (EOGs).

Results: After 22 weeks, a typical type 2/Th2-mediated inflammatory profile was obtained, as demonstrated by increased interleukin (IL)-4, IL-5, and IL-13 in the OE. The number of mast cells and eosinophils was increased, and infiltration of these cells into the olfactory mucosa was also observed. In parallel, transcriptomic and histology analyses indicated a decreased number of immature olfactory neurons, possibly due to decreased renewal. However, the number of mature sensory neurons was not affected and neither the EOG nor olfactory behavior was impaired.

Conclusion: Our mouse model of CRS displayed an allergic response to HDM + SEB administration, including the type 2/Th2 inflammatory profile characteristic of human eosinophilic CRSwNP. Although the sense of smell did not appear to be altered in these conditions, the data reveal the influence of chronic inflammation on olfactory neurogenesis, suggesting that factors unique to humans may be involved in CRSwNP-associated anosmia.
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http://dx.doi.org/10.1111/all.13559DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6590422PMC
March 2019

Monocyte NOTCH2 expression predicts IFN-β immunogenicity in multiple sclerosis patients.

JCI Insight 2018 06 7;3(11). Epub 2018 Jun 7.

Department of Rheumatology, University College Hospital, London, United Kingdom.

Multiple sclerosis (MS) is an autoimmune disease characterized by CNS inflammation leading to demyelination and axonal damage. IFN-β is an established treatment for MS; however, up to 30% of IFN-β-treated MS patients develop neutralizing antidrug antibodies (nADA), leading to reduced drug bioactivity and efficacy. Mechanisms driving antidrug immunogenicity remain uncertain, and reliable biomarkers to predict immunogenicity development are lacking. Using high-throughput flow cytometry, NOTCH2 expression on CD14+ monocytes and increased frequency of proinflammatory monocyte subsets were identified as baseline predictors of nADA development in MS patients treated with IFN-β. The association of this monocyte profile with nADA development was validated in 2 independent cross-sectional MS patient cohorts and a prospective cohort followed before and after IFN-β administration. Reduced monocyte NOTCH2 expression in nADA+ MS patients was associated with NOTCH2 activation measured by increased expression of Notch-responsive genes, polarization of monocytes toward a nonclassical phenotype, and increased proinflammatory IL-6 production. NOTCH2 activation was T cell dependent and was only triggered in the presence of serum from nADA+ patients. Thus, nADA development was driven by a proinflammatory environment that triggered activation of the NOTCH2 signaling pathway prior to first IFN-β administration.
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http://dx.doi.org/10.1172/jci.insight.99274DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6124413PMC
June 2018

CODV-Ig, a universal bispecific tetravalent and multifunctional immunoglobulin format for medical applications.

MAbs 2016 07 16;8(5):867-78. Epub 2016 Mar 16.

a Sanofi-Aventis Deutschland GmbH, R&D, Global Biotherapeutics, Industriepark Hoechst , Frankfurt am Main , Germany.

Bispecific immunoglobulins (Igs) typically contain at least two distinct variable domains (Fv) that bind to two different target proteins. They are conceived to facilitate clinical development of biotherapeutic agents for diseases where improved clinical outcome is obtained or expected by combination therapy compared to treatment by single agents. Almost all existing formats are linear in their concept and differ widely in drug-like and manufacture-related properties. To overcome their major limitations, we designed cross-over dual variable Ig-like proteins (CODV-Ig). Their design is akin to the design of circularly closed repeat architectures. Indeed, initial results showed that the traditional approach of utilizing (G4S)x linkers for biotherapeutics design does not identify functional CODV-Igs. Therefore, we applied an unprecedented molecular modeling strategy for linker design that consistently results in CODV-Igs with excellent biochemical and biophysical properties. CODV architecture results in a circular self-contained structure functioning as a self-supporting truss that maintains the parental antibody affinities for both antigens without positional effects. The format is universally suitable for therapeutic applications targeting both circulating and membrane-localized proteins. Due to the full functionality of the Fc domains, serum half-life extension as well as antibody- or complement-dependent cytotoxicity may support biological efficiency of CODV-Igs. We show that judicious choice in combination of epitopes and paratope orientations of bispecific biotherapeutics is anticipated to be critical for clinical outcome. Uniting the major advantages of alternative bispecific biotherapeutics, CODV-Igs are applicable in a wide range of disease areas for fast-track multi-parametric drug optimization.
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http://dx.doi.org/10.1080/19420862.2016.1162932DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4968095PMC
July 2016

Selective blockade of the hydrolysis of the endocannabinoid 2-arachidonoylglycerol impairs learning and memory performance while producing antinociceptive activity in rodents.

Sci Rep 2015 Jan 6;5:7642. Epub 2015 Jan 6.

Exploratory Unit, Montpellier, France.

Monoacylglycerol lipase (MAGL) represents a primary degradation enzyme of the endogenous cannabinoid (eCB), 2-arachidonoyglycerol (2-AG). This study reports a potent covalent MAGL inhibitor, SAR127303. The compound behaves as a selective and competitive inhibitor of mouse and human MAGL, which potently elevates hippocampal levels of 2-AG in mice. In vivo, SAR127303 produces antinociceptive effects in assays of inflammatory and visceral pain. In addition, the drug alters learning performance in several assays related to episodic, working and spatial memory. Moreover, long term potentiation (LTP) of CA1 synaptic transmission and acetylcholine release in the hippocampus, two hallmarks of memory function, are both decreased by SAR127303. Although inactive in acute seizure tests, repeated administration of SAR127303 delays the acquisition and decreases kindled seizures in mice, indicating that the drug slows down epileptogenesis, a finding deserving further investigation to evaluate the potential of MAGL inhibitors as antiepileptics. However, the observation that 2-AG hydrolysis blockade alters learning and memory performance, suggests that such drugs may have limited value as therapeutic agents.
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http://dx.doi.org/10.1038/srep07642DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4284516PMC
January 2015

Engineering protein therapeutics: predictive performances of a structure-based virtual affinity maturation protocol.

J Chem Inf Model 2012 Aug 24;52(8):2204-14. Epub 2012 Jul 24.

SANOFI R&D, Centre de Recherche de Vitry/Alfortville, LGCR/SDI, 13 quai Jules Guesde-BP 14-94403 Vitry-sur-Seine Cedex, France.

The implementation of a structure based virtual affinity maturation protocol and evaluation of its predictivity are presented. The in silico protocol is based on conformational sampling of the interface residues (using the Dead End Elimination/A* algorithm), followed by the estimation of the change of free energy of binding due to a point mutation, applying MM/PBSA calculations. Several implementations of the protocol have been evaluated for 173 mutations in 7 different protein complexes for which experimental data were available: the use of the Boltzamnn averaged predictor based on the free energy of binding (ΔΔG(*)) combined with the one based on its polar component only (ΔΔE(pol*)) led to the proposal of a subset of mutations out of which 45% would have successfully enhanced the binding. When focusing on those mutations that are less likely to be introduced by natural in vivo maturation methods (99 mutations with at least two base changes in the codon), the success rate is increased to 63%. In another evaluation, focusing on 56 alanine scanning mutations, the in silico protocol was able to detect 89% of the hot-spots.
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http://dx.doi.org/10.1021/ci3001474DOI Listing
August 2012

Tricyclic series of heat shock protein 90 (Hsp90) inhibitors part I: discovery of tricyclic imidazo[4,5-c]pyridines as potent inhibitors of the Hsp90 molecular chaperone.

J Med Chem 2011 Oct 5;54(20):7206-19. Epub 2011 Oct 5.

Sanofi-Aventis Research and Development, 13 Quai Jules Guesde, BP 14, 94400 Vitry-sur-Seine, France.

A novel class of heat shock protein 90 (Hsp90) inhibitors was developed after a low throughput screen (LTS) of a focused library containing approximately 21K compounds selected by virtual screening. The initial [1-{3-H-imidazo[4-5-c]pyridin-2-yl}-3,4-dihydro-2H-pyrido[2,1-a]isoindole-6-one] (1) compound showed moderate activity (IC(50) = 7.6 μM on Hsp82, the yeast homologue of Hsp90). A high-resolution X-ray structure shows that compound 1 binds into an "induced" hydrophobic pocket, 10-15 Å away from the ATP/resorcinol binding site. Iterative cycles of structure-based drug design (SBDD) and chemical synthesis led to the design and preparation of analogues with improved affinity. These optimized molecules make productive interactions within the ATP binding site as reported by other Hsp90 inhibitors. This resulted in compound 8, which is a highly potent inhibitor in biochemical and cellular assays (K(d) = 0.35 nM on Hsp90; IC(50) = 30 nM on SKBr3 mammary carcinoma cells) and in an in vivo leukemia model.
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http://dx.doi.org/10.1021/jm200784mDOI Listing
October 2011

Variations in the colchicine-binding domain provide insight into the structural switch of tubulin.

Proc Natl Acad Sci U S A 2009 Aug 5;106(33):13775-9. Epub 2009 Aug 5.

Laboratoire d'Enzymologie et Biochimie Structurales, Centre National de la Recherche Scientifique, Bâtiment 34, 1, avenue de la Terrasse, 91198 Gif sur Yvette, France.

Structural changes occur in the alphabeta-tubulin heterodimer during the microtubule assembly/disassembly cycle. Their most prominent feature is a transition from a straight, microtubular structure to a curved structure. There is a broad range of small molecule compounds that disturbs the microtubule cycle, a class of which targets the colchicine-binding site and prevents microtubule assembly. This class includes compounds with very different chemical structures, and it is presently unknown whether they prevent tubulin polymerization by the same mechanism. To address this issue, we have determined the structures of tubulin complexed with a set of such ligands and show that they interfere with several of the movements of tubulin subunits structural elements upon its transition from curved to straight. We also determined the structure of tubulin unliganded at the colchicine site; this reveals that a beta-tubulin loop (termed T7) flips into this site. As with colchicine site ligands, this prevents a helix which is at the interface with alpha-tubulin from stacking onto a beta-tubulin beta sheet as in straight protofilaments. Whereas in the presence of these ligands the interference with microtubule assembly gets frozen, by flipping in and out the beta-subunit T7 loop participates in a reversible way in the resistance to straightening that opposes microtubule assembly. Our results suggest that it thereby contributes to microtubule dynamic instability.
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http://dx.doi.org/10.1073/pnas.0904223106DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2728970PMC
August 2009

Escherichia coli FolC structure reveals an unexpected dihydrofolate binding site providing an attractive target for anti-microbial therapy.

J Biol Chem 2005 May 10;280(19):18916-22. Epub 2005 Feb 10.

Department of Structural Biology, Aventis Pharma, 13 Quai J. Guesde, F-94403 Vitry/Seine, France.

In some bacteria, such as Escherichia coli, the addition of L-glutamate to dihydropteroate (dihydrofolate synthetase activity) and the subsequent additions of L-glutamate to tetrahydrofolate (folylpolyglutamate synthetase (FPGS) activity) are catalyzed by the same enzyme, FolC. The crystal structure of E. coli FolC is described in this paper. It showed strong similarities to that of the FPGS enzyme of Lactobacillus casei within the ATP binding site and the catalytic site, as do all other members of the Mur synthethase superfamily. FolC structure revealed an unexpected dihydropteroate binding site very different from the folate site identified previously in the FPGS structure. The relevance of this site is exemplified by the presence of phosphorylated dihydropteroate, a reaction intermediate in the DHFS reaction. L. casei FPGS is considered a relevant model for human FPGS. As such, the presence of a folate binding site in E. coli FolC, which is different from the one seen in FPGS enzymes, provides avenues for the design of specific inhibitors of this enzyme in antimicrobial therapy.
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http://dx.doi.org/10.1074/jbc.M413799200DOI Listing
May 2005

Molecular structures of human factor Xa complexed with ketopiperazine inhibitors: preference for a neutral group in the S1 pocket.

J Med Chem 2003 Feb;46(5):685-90

Department of Structural Biology, Aventis Pharma, 13, Quai J. Guesde, F-94403 Vitry/Seine, France.

The structures of the noncovalent complex of human factor Xa (fXa) with four non-peptide inhibitors containing a central sulfonylpiperazinone scaffold have been determined to about 2.1 A resolution. Highly potent fXa inhibitors containing both neutral groups such as chlorobenzothiophene or chlorothiophene and basic groups such as benzamidine were shown to interact in the S1 pocket through the neutral group whereas the S4 pocket is occupied by the basic moiety. The scaffold comprising the sulfonyl keto piperazine moiety might play a pivotal role in the orientation of substituents, since there is a strong hydrogen bond between Gly219 of fXa and the carbonyl oxygen of the piperazine. This unique "reverse" binding mode is heretofore unreported in fXa and shows that electrostatic interactions in the S1 subsite are not an absolute requirement to maintain high affinity. Selectivity against other serine proteases can be readily explained in light of these structural results. It has opened up new prospects for designing fXa inhibitors with increased oral bioavailability.
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http://dx.doi.org/10.1021/jm0203837DOI Listing
February 2003

Discovery of an orally efficacious inhibitor of coagulation factor Xa which incorporates a neutral P1 ligand.

J Med Chem 2003 Feb;46(5):681-4

Department of Medicinal Chemistry and Department of Biology, Aventis Pharmaceuticals, Route 202-206, Bridgewater, New Jersey 08807-0800, USA.

The discovery and SAR of ketopiperazino methylazaindole factor Xa inhibitors are described. Structure-activity data suggesting that this class of inhibitors does not bind in the canonical mode were confirmed by an X-ray crystal structure showing the neutral haloaromatic bound in the S(1) subsite. The most potent azaindole, 33 (RPR209685), is selective against related serine proteases and attains higher levels of exposure upon oral dosing than comparable benzamidines and benzamidine isosteres. Compound 33 was efficacious in the canine AV model of thrombosis.
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http://dx.doi.org/10.1021/jm020384zDOI Listing
February 2003

The crystal structures of four peptide deformylases bound to the antibiotic actinonin reveal two distinct types: a platform for the structure-based design of antibacterial agents.

J Mol Biol 2002 Jul;320(5):951-62

Drug Innovation & Approval, Aventis Pharma, 13 Quai Jules Guesde, BP.14, F-94403, Vitry-sur-Seine, France.

Bacterial peptide deformylase (PDF) belongs to a sub-family of metalloproteases that catalyse the removal of the N-terminal formyl group from newly synthesised proteins. PDF is essential in prokaryotes and conserved throughout the eubacteria. It is therefore considered an attractive target for developing new antibacterial agents. Here, we report the crystal structures of four bacterial deformylases, free or bound to the naturally occurring antibiotic actinonin, including two from the major bacterial pathogens Pseudomonas aeruginosa and Staphylococcus aureus. The overall tertiary structure is essentially conserved but shows significant differences, namely at the C terminus, which are directly related to the deformylase type (i.e. I or II) they belong to. The geometry around the catalytic metal ion exhibits a high level of similarity within the different enzymes, as does the binding mode of actinonin to the various deformylases. However, some significant structural differences are found in the vicinity of the active site, highlighting the structural and molecular requirements for the design of a deformylase inhibitor active against a broad spectrum of bacterial strains.
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http://dx.doi.org/10.1016/s0022-2836(02)00549-1DOI Listing
July 2002