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Mulamreddy R, Hou X, Chemtob S, Lubell WD. Synthesis of 5- and 7-hydroxy indolizidin-2-one prostaglandin-F 2α modulators and activity on myometrial contractility towards development of agents for delaying preterm birth. J Pept Sci 2023; 29:e3455. [PMID: 36184819 DOI: 10.1002/psc.3455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 09/15/2022] [Accepted: 09/28/2022] [Indexed: 11/06/2022]
Abstract
In pursuit of more effective-labor delaying tocolytic agents, the prostaglandin F2α (PGF2α) receptor (FP) modulator PDC113.824 [(6S)-2] represents a potent lead for developing therapy to treat preterm birth. Derivatives of FP modulator (6S)-2 were synthesized, possessing respectively 5- and 7-hydroxyl groups on the indolizidin-2-one amino acid (I2 aa) residue. The effects of the alcohol substituents were examined in a PGF2α-induced myometrial contraction assay. Based on knowledge of dihedral angle values of model I2 aa peptides from X-ray analyses, the results of the study indicate respectively encouraging and limited potential for creating improved tocolytic agents by modifications at the 5- and 7-positions.
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Affiliation(s)
| | - Xin Hou
- Centre Hospitalier Universitaire Sainte-Justine Research Center, Montréal, Québec, Canada
| | - Sylvain Chemtob
- Centre Hospitalier Universitaire Sainte-Justine Research Center, Montréal, Québec, Canada
| | - William D Lubell
- Département de Chimie, Université de Montréal, Montréal, Québec, Canada
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2
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Olson KM, Traynor JR, Alt A. Allosteric Modulator Leads Hiding in Plain Site: Developing Peptide and Peptidomimetics as GPCR Allosteric Modulators. Front Chem 2021; 9:671483. [PMID: 34692635 PMCID: PMC8529114 DOI: 10.3389/fchem.2021.671483] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 08/02/2021] [Indexed: 12/17/2022] Open
Abstract
Allosteric modulators (AMs) of G-protein coupled receptors (GPCRs) are desirable drug targets because they can produce fewer on-target side effects, improved selectivity, and better biological specificity (e.g., biased signaling or probe dependence) than orthosteric drugs. An underappreciated source for identifying AM leads are peptides and proteins-many of which were evolutionarily selected as AMs-derived from endogenous protein-protein interactions (e.g., transducer/accessory proteins), intramolecular receptor contacts (e.g., pepducins or extracellular domains), endogenous peptides, and exogenous libraries (e.g., nanobodies or conotoxins). Peptides offer distinct advantages over small molecules, including high affinity, good tolerability, and good bioactivity, and specific disadvantages, including relatively poor metabolic stability and bioavailability. Peptidomimetics are molecules that combine the advantages of both peptides and small molecules by mimicking the peptide's chemical features responsible for bioactivity while improving its druggability. This review 1) discusses sources and strategies to identify peptide/peptidomimetic AMs, 2) overviews strategies to convert a peptide lead into more drug-like "peptidomimetic," and 3) critically analyzes the advantages, disadvantages, and future directions of peptidomimetic AMs. While small molecules will and should play a vital role in AM drug discovery, peptidomimetics can complement and even exceed the advantages of small molecules, depending on the target, site, lead, and associated factors.
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Affiliation(s)
- Keith M. Olson
- Department of Pharmacology and Edward F Domino Research Center, University of Michigan, Ann Arbor, MI, United States
| | - John R. Traynor
- Department of Pharmacology and Edward F Domino Research Center, University of Michigan, Ann Arbor, MI, United States
- Department of Medicinal Chemistry, College of Pharmacy, University of Michigan, Ann Arbor, MI, United States
| | - Andrew Alt
- Department of Pharmacology and Edward F Domino Research Center, University of Michigan, Ann Arbor, MI, United States
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, United States
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Mulamreddy R, Hou X, Chemtob S, Lubell WD. 6-Hydroxymethyl Indolizidin-2-one Amino Acid Synthesis, Conformational Analysis, and Biomedical Application as Dipeptide Surrogates in Prostaglandin-F 2α Modulators. Org Lett 2021; 23:5192-5196. [PMID: 34161105 DOI: 10.1021/acs.orglett.1c01733] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
6-Hydroxymethyl indolizidin-2-one amino acids were synthesized in 10 steps from l-serine by intramolecular ring opening of a symmetrical epoxide and lactam formation. X-ray analyses indicated the bicycles replicated ideal peptide type II' β-turn central dihedral angle geometry. Inside a prostaglandin-F2α receptor modulator, the 6-hydroxymethyl analogue retained inhibitory activity on myometrial contractility.
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Affiliation(s)
- Ramakotaiah Mulamreddy
- Département de Chimie, Université de Montréal, C.P. 6128, Succursale Centre-Ville, Montréal, Québec H3C3J7, Canada
| | - Xin Hou
- Centre Hospitalier Universitaire Sainte-Justine Research Center, Montréal H3T 1C5, QC, Canada
| | - Sylvain Chemtob
- Centre Hospitalier Universitaire Sainte-Justine Research Center, Montréal H3T 1C5, QC, Canada
| | - William D Lubell
- Département de Chimie, Université de Montréal, C.P. 6128, Succursale Centre-Ville, Montréal, Québec H3C3J7, Canada
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Siricilla S, Iwueke CC, Herington JL. Drug discovery strategies for the identification of novel regulators of uterine contractility. CURRENT OPINION IN PHYSIOLOGY 2019; 13:71-86. [PMID: 32864532 DOI: 10.1016/j.cophys.2019.10.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Preterm birth and postpartum hemorrhage are the leading causes of neonatal and maternal morbidities worldwide, respectively. Current clinically utilized tocolytics and uterotonics to manage these obstetric conditions are limited due to their off-target effects and/or lack of efficacy. Thus, an ideal tocolytic or uterotonic would be uterine-selective with rapid onset and long-duration efficacy. Here, we discuss strategies for the discovery of new therapeutic targets and compounds that regulate uterine contractility with the aforementioned properties.
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Affiliation(s)
- Shajila Siricilla
- Division of Neonatology, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Chisom C Iwueke
- Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Jennifer L Herington
- Division of Neonatology, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA.,Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
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Millet-Boureima C, Chingle R, Lubell WD, Gamberi C. Cyst Reduction in a Polycystic Kidney Disease Drosophila Model Using Smac Mimics. Biomedicines 2019; 7:biomedicines7040082. [PMID: 31635379 PMCID: PMC6966561 DOI: 10.3390/biomedicines7040082] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2019] [Revised: 10/11/2019] [Accepted: 10/15/2019] [Indexed: 12/13/2022] Open
Abstract
Autosomal dominant polycystic kidney disease (ADPKD) is an inherited malady affecting 12.5 million people worldwide. Therapeutic options to treat PKD are limited, due in part to lack of precise knowledge of underlying pathological mechanisms. Mimics of the second mitochondria-derived activator of caspases (Smac) have exhibited activity as antineoplastic agents and reported recently to ameliorate cysts in a murine ADPKD model, possibly by differentially targeting cystic cells and sparing the surrounding tissue. A first-in-kind Drosophila PKD model has now been employed to probe further the activity of novel Smac mimics. Substantial reduction of cystic defects was observed in the Malpighian (renal) tubules of treated flies, underscoring mechanistic conservation of the cystic pathways and potential for efficient testing of drug prototypes in this PKD model. Moreover, the observed differential rescue of the anterior and posterior tubules overall, and within their physiologically diverse intermediate and terminal regions implied a nuanced response in distinct tubular regions contingent upon the structure of the Smac mimic. Knowledge gained from studying Smac mimics reveals the capacity for the Drosophila model to precisely probe PKD pharmacology highlighting the value for such critical evaluation of factors implicated in renal function and pathology.
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Affiliation(s)
| | - Ramesh Chingle
- Département de Chimie, Université de Montréal, Montreal, QC H3T 1J4, Canada.
| | - William D Lubell
- Département de Chimie, Université de Montréal, Montreal, QC H3T 1J4, Canada.
| | - Chiara Gamberi
- Biology Department, Concordia University, Montreal, QC H4B 1R6, Canada.
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Mir FM, Atmuri NDP, Bourguet CB, Fores JR, Hou X, Chemtob S, Lubell WD. Paired Utility of Aza-Amino Acyl Proline and Indolizidinone Amino Acid Residues for Peptide Mimicry: Conception of Prostaglandin F2α Receptor Allosteric Modulators That Delay Preterm Birth. J Med Chem 2019; 62:4500-4525. [PMID: 30932486 DOI: 10.1021/acs.jmedchem.9b00056] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Peptide mimicry employing a combination of aza-amino acyl proline and indolizidinone residues has been used to develop allosteric modulators of the prostaglandin F2α receptor. The systematic study of the N-terminal phenylacetyl moiety and the conformation and side chain functions of the central turn dipeptide residue has demonstrated the sensitive relationships between modulator activity and topology. Examination of aza-Gly-Pro and aza-Phe-Pro analogs 2a and 2b in a murine preterm labor model featuring treatment with lipopolysaccharide demonstrated their capacity to extend significantly (>20 h) the average time of delivery offering new prototypes for delaying premature birth.
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Affiliation(s)
- Fatemeh M Mir
- Département de Chimie , Université de Montréal , C.P. 6128 Succursale Centre-Ville , Montréal H3C 3J7 QC , Canada
| | - N D Prasad Atmuri
- Département de Chimie , Université de Montréal , C.P. 6128 Succursale Centre-Ville , Montréal H3C 3J7 QC , Canada
| | - Carine B Bourguet
- Département de Chimie , Université de Montréal , C.P. 6128 Succursale Centre-Ville , Montréal H3C 3J7 QC , Canada
| | - Jennifer Rodon Fores
- Département de Chimie , Université de Montréal , C.P. 6128 Succursale Centre-Ville , Montréal H3C 3J7 QC , Canada
| | - Xin Hou
- Centre Hospitalier Universitaire Sainte-Justine Research Center , Montréal H3T 1C5 , QC , Canada
| | - Sylvain Chemtob
- Centre Hospitalier Universitaire Sainte-Justine Research Center , Montréal H3T 1C5 , QC , Canada
| | - William D Lubell
- Département de Chimie , Université de Montréal , C.P. 6128 Succursale Centre-Ville , Montréal H3C 3J7 QC , Canada
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Pant A, Kumar R, Wani NA, Verma S, Sharma R, Pande V, Saxena AK, Dixit R, Rai R, Pandey KC. Allosteric Site Inhibitor Disrupting Auto-Processing of Malarial Cysteine Proteases. Sci Rep 2018; 8:16193. [PMID: 30385827 PMCID: PMC6212536 DOI: 10.1038/s41598-018-34564-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 10/16/2018] [Indexed: 02/08/2023] Open
Abstract
Falcipains are major haemoglobinases of Plasmodium falciparum required for parasite growth and development. They consist of pro- and mature domains that interact via 'hot-spot' interactions and maintain the structural integrity of enzyme in zymogen state. Upon sensing the acidic environment, these interactions dissociate and active enzyme is released. For inhibiting falcipains, several active site inhibitors exist, however, compounds that target via allosteric mechanism remains uncharacterized. Therefore, we designed and synthesized six azapeptide compounds, among which, NA-01 & NA-03 arrested parasite growth by specifically blocking the auto-processing of falcipains. Inhibitors showed high affinity for enzymes in presence of the prodomain without affecting the secondary structure. Binding of NA-03 at the interface induced rigidity in the prodomain preventing structural reorganization. We further reported a histidine-dependent activation of falcipain. Collectively, for the first time we provide a framework for blocking the allosteric site of crucial haemoglobinases of the human malaria parasite. Targeting the allosteric site could provide high selectivity and less vulnerable to drug resistance.
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Affiliation(s)
- A Pant
- ICMR-National Institute of Malaria Research, Dwarka Sector 8, New Delhi, India
- Department of Biotechnology, Kumaun University, Nainital, Uttarakhand, India
| | - R Kumar
- Integrated Science Lab, Umeå University, Umeå, Sweden
| | - N A Wani
- Medicinal Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Jammu, India
| | - S Verma
- ICMR-National Institute of Malaria Research, Dwarka Sector 8, New Delhi, India
- Department of Biotechnology, Kumaun University, Nainital, Uttarakhand, India
| | - R Sharma
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - V Pande
- Department of Biotechnology, Kumaun University, Nainital, Uttarakhand, India
| | - A K Saxena
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - R Dixit
- ICMR-National Institute of Malaria Research, Dwarka Sector 8, New Delhi, India
| | - R Rai
- Medicinal Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Jammu, India
| | - K C Pandey
- ICMR-National Institute of Malaria Research, Dwarka Sector 8, New Delhi, India.
- Department of Biochemistry, ICMR-National Institute for Research in Environmental Health, Bhopal, MP - 462001, India.
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Pohl O, Chollet A, Kim SH, Riaposova L, Spézia F, Gervais F, Guillaume P, Lluel P, Méen M, Lemaux F, Terzidou V, Bennett PR, Gotteland JP. OBE022, an Oral and Selective Prostaglandin F 2α Receptor Antagonist as an Effective and Safe Modality for the Treatment of Preterm Labor. J Pharmacol Exp Ther 2018; 366:349-364. [PMID: 29777040 DOI: 10.1124/jpet.118.247668] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 05/15/2018] [Indexed: 01/02/2023] Open
Abstract
Preterm birth is the major challenge in obstetrics, affecting ∼10% of pregnancies. Pan-prostaglandin synthesis inhibitors [nonsteroidal anti-inflammatory drugs (NSAIDs)] prevent preterm labor and prolong pregnancy but raise concerns about fetal renal and cardiovascular safety. We conducted preclinical studies examining the tocolytic effect and fetal safety of the oral prodrug candidate OBE022 [(S)-2-amino-3-methyl-butyric acid (S)-3-{[(S)-3-(biphenyl-4-sulfonyl)-thiazolidine-2-carbonyl]-amino}-3-(4-fluoro-phenyl)-propyl ester] and its parent OBE002 [(S)-3-(biphenyl-4-sulfonyl)-thiazolidine-2-carboxylic acid [(S)-1-(4-fluoro-phenyl)-3-hydroxy-propyl]-amide], both potent and highly selective antagonist of the contractile prostaglandin F2α (PGF2α ) receptor (FP). Efficacy of OBE022 and OBE002, alone and in combination with other tocolytics, was assessed in human tissues and pregnant animal models for inhibition of uterine contraction and delay of parturition. Selective safety of OBE022 and/or OBE002, compared with NSAID indomethacin, was assessed on renal function, closure of the ductus arteriosus, and inhibition of platelet aggregation. In in vitro studies, OBE002 inhibited spontaneous, oxytocin- and PGF2α -induced human myometrial contractions alone and was more effective in combination with atosiban or nifedipine. In in vivo studies, OBE022 and OBE002 reduced spontaneous contractions in near-term pregnant rats. In pregnant mice, OBE022 delayed RU486 [(8S,11R,13S,14S,17S)-11-[4-(dimethylamino)phenyl]-17-hydroxy-13-methyl-17-prop-1-ynyl-1,2,6,7,8,11,12,14,15,16-decahydrocyclopenta[a]phenanthren-3-one] -induced parturition and exerted synergistic effects in combination with nifedipine. OBE022 and/or OBE002 did not show the fetal side effects of ductus arteriosus constriction, impairment of kidney function, or inhibition of platelet aggregation observed with indomethacin. Orally active OBE022 and OBE002 exhibits potent tocolytic effects on human tissues ex vivo and animal models in vivo without causing the adverse fetal side effects seen with indomethacin. Selectively targeting the FP receptor in combination with existing tocolytics may be an effective strategy for preventing or delaying preterm delivery.
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Affiliation(s)
- Oliver Pohl
- ObsEva SA, Plan-les-Ouates, Geneva, Switzerland (O.P., A.C., J.-P.G.); Imperial College London, Parturition Research Group, Institute of Reproductive and Developmental Biology, Hammersmith Hospital Campus, East Acton, London, United Kingdom (S.H.K., L.R., V.T., P.R.B.); Citoxlab, Evreux, France (F.S., F.G.); Porsolt Research Laboratory, Le Genest-Saint-Isle, France (P.G.); Urosphere SAS, Toulouse, France (P.L., M.M.); BioTrial, Rennes, France (F.L.); and André Chollet Consulting, Tannay, Switzerland (A.C.)
| | - André Chollet
- ObsEva SA, Plan-les-Ouates, Geneva, Switzerland (O.P., A.C., J.-P.G.); Imperial College London, Parturition Research Group, Institute of Reproductive and Developmental Biology, Hammersmith Hospital Campus, East Acton, London, United Kingdom (S.H.K., L.R., V.T., P.R.B.); Citoxlab, Evreux, France (F.S., F.G.); Porsolt Research Laboratory, Le Genest-Saint-Isle, France (P.G.); Urosphere SAS, Toulouse, France (P.L., M.M.); BioTrial, Rennes, France (F.L.); and André Chollet Consulting, Tannay, Switzerland (A.C.)
| | - Sung Hye Kim
- ObsEva SA, Plan-les-Ouates, Geneva, Switzerland (O.P., A.C., J.-P.G.); Imperial College London, Parturition Research Group, Institute of Reproductive and Developmental Biology, Hammersmith Hospital Campus, East Acton, London, United Kingdom (S.H.K., L.R., V.T., P.R.B.); Citoxlab, Evreux, France (F.S., F.G.); Porsolt Research Laboratory, Le Genest-Saint-Isle, France (P.G.); Urosphere SAS, Toulouse, France (P.L., M.M.); BioTrial, Rennes, France (F.L.); and André Chollet Consulting, Tannay, Switzerland (A.C.)
| | - Lucia Riaposova
- ObsEva SA, Plan-les-Ouates, Geneva, Switzerland (O.P., A.C., J.-P.G.); Imperial College London, Parturition Research Group, Institute of Reproductive and Developmental Biology, Hammersmith Hospital Campus, East Acton, London, United Kingdom (S.H.K., L.R., V.T., P.R.B.); Citoxlab, Evreux, France (F.S., F.G.); Porsolt Research Laboratory, Le Genest-Saint-Isle, France (P.G.); Urosphere SAS, Toulouse, France (P.L., M.M.); BioTrial, Rennes, France (F.L.); and André Chollet Consulting, Tannay, Switzerland (A.C.)
| | - François Spézia
- ObsEva SA, Plan-les-Ouates, Geneva, Switzerland (O.P., A.C., J.-P.G.); Imperial College London, Parturition Research Group, Institute of Reproductive and Developmental Biology, Hammersmith Hospital Campus, East Acton, London, United Kingdom (S.H.K., L.R., V.T., P.R.B.); Citoxlab, Evreux, France (F.S., F.G.); Porsolt Research Laboratory, Le Genest-Saint-Isle, France (P.G.); Urosphere SAS, Toulouse, France (P.L., M.M.); BioTrial, Rennes, France (F.L.); and André Chollet Consulting, Tannay, Switzerland (A.C.)
| | - Frédéric Gervais
- ObsEva SA, Plan-les-Ouates, Geneva, Switzerland (O.P., A.C., J.-P.G.); Imperial College London, Parturition Research Group, Institute of Reproductive and Developmental Biology, Hammersmith Hospital Campus, East Acton, London, United Kingdom (S.H.K., L.R., V.T., P.R.B.); Citoxlab, Evreux, France (F.S., F.G.); Porsolt Research Laboratory, Le Genest-Saint-Isle, France (P.G.); Urosphere SAS, Toulouse, France (P.L., M.M.); BioTrial, Rennes, France (F.L.); and André Chollet Consulting, Tannay, Switzerland (A.C.)
| | - Philippe Guillaume
- ObsEva SA, Plan-les-Ouates, Geneva, Switzerland (O.P., A.C., J.-P.G.); Imperial College London, Parturition Research Group, Institute of Reproductive and Developmental Biology, Hammersmith Hospital Campus, East Acton, London, United Kingdom (S.H.K., L.R., V.T., P.R.B.); Citoxlab, Evreux, France (F.S., F.G.); Porsolt Research Laboratory, Le Genest-Saint-Isle, France (P.G.); Urosphere SAS, Toulouse, France (P.L., M.M.); BioTrial, Rennes, France (F.L.); and André Chollet Consulting, Tannay, Switzerland (A.C.)
| | - Philippe Lluel
- ObsEva SA, Plan-les-Ouates, Geneva, Switzerland (O.P., A.C., J.-P.G.); Imperial College London, Parturition Research Group, Institute of Reproductive and Developmental Biology, Hammersmith Hospital Campus, East Acton, London, United Kingdom (S.H.K., L.R., V.T., P.R.B.); Citoxlab, Evreux, France (F.S., F.G.); Porsolt Research Laboratory, Le Genest-Saint-Isle, France (P.G.); Urosphere SAS, Toulouse, France (P.L., M.M.); BioTrial, Rennes, France (F.L.); and André Chollet Consulting, Tannay, Switzerland (A.C.)
| | - Murielle Méen
- ObsEva SA, Plan-les-Ouates, Geneva, Switzerland (O.P., A.C., J.-P.G.); Imperial College London, Parturition Research Group, Institute of Reproductive and Developmental Biology, Hammersmith Hospital Campus, East Acton, London, United Kingdom (S.H.K., L.R., V.T., P.R.B.); Citoxlab, Evreux, France (F.S., F.G.); Porsolt Research Laboratory, Le Genest-Saint-Isle, France (P.G.); Urosphere SAS, Toulouse, France (P.L., M.M.); BioTrial, Rennes, France (F.L.); and André Chollet Consulting, Tannay, Switzerland (A.C.)
| | - Frédérique Lemaux
- ObsEva SA, Plan-les-Ouates, Geneva, Switzerland (O.P., A.C., J.-P.G.); Imperial College London, Parturition Research Group, Institute of Reproductive and Developmental Biology, Hammersmith Hospital Campus, East Acton, London, United Kingdom (S.H.K., L.R., V.T., P.R.B.); Citoxlab, Evreux, France (F.S., F.G.); Porsolt Research Laboratory, Le Genest-Saint-Isle, France (P.G.); Urosphere SAS, Toulouse, France (P.L., M.M.); BioTrial, Rennes, France (F.L.); and André Chollet Consulting, Tannay, Switzerland (A.C.)
| | - Vasso Terzidou
- ObsEva SA, Plan-les-Ouates, Geneva, Switzerland (O.P., A.C., J.-P.G.); Imperial College London, Parturition Research Group, Institute of Reproductive and Developmental Biology, Hammersmith Hospital Campus, East Acton, London, United Kingdom (S.H.K., L.R., V.T., P.R.B.); Citoxlab, Evreux, France (F.S., F.G.); Porsolt Research Laboratory, Le Genest-Saint-Isle, France (P.G.); Urosphere SAS, Toulouse, France (P.L., M.M.); BioTrial, Rennes, France (F.L.); and André Chollet Consulting, Tannay, Switzerland (A.C.)
| | - Phillip R Bennett
- ObsEva SA, Plan-les-Ouates, Geneva, Switzerland (O.P., A.C., J.-P.G.); Imperial College London, Parturition Research Group, Institute of Reproductive and Developmental Biology, Hammersmith Hospital Campus, East Acton, London, United Kingdom (S.H.K., L.R., V.T., P.R.B.); Citoxlab, Evreux, France (F.S., F.G.); Porsolt Research Laboratory, Le Genest-Saint-Isle, France (P.G.); Urosphere SAS, Toulouse, France (P.L., M.M.); BioTrial, Rennes, France (F.L.); and André Chollet Consulting, Tannay, Switzerland (A.C.)
| | - Jean-Pierre Gotteland
- ObsEva SA, Plan-les-Ouates, Geneva, Switzerland (O.P., A.C., J.-P.G.); Imperial College London, Parturition Research Group, Institute of Reproductive and Developmental Biology, Hammersmith Hospital Campus, East Acton, London, United Kingdom (S.H.K., L.R., V.T., P.R.B.); Citoxlab, Evreux, France (F.S., F.G.); Porsolt Research Laboratory, Le Genest-Saint-Isle, France (P.G.); Urosphere SAS, Toulouse, France (P.L., M.M.); BioTrial, Rennes, France (F.L.); and André Chollet Consulting, Tannay, Switzerland (A.C.)
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Ramakrishna E, Dev K, Maurya SW, Siddiqui IR, Maurya R. Hypervalent iodine (III)-mediated oxidation of aryl sulfonylhydrazones: A facile synthesis of N-aroyl-N′-acyl arylsulfonylhydrazides. Tetrahedron Lett 2017. [DOI: 10.1016/j.tetlet.2016.12.085] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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St-Cyr DJ, García-Ramos Y, Doan ND, Lubell WD. Aminolactam, N-Aminoimidazolone, and N-Aminoimdazolidinone Peptide Mimics. TOPICS IN HETEROCYCLIC CHEMISTRY 2017. [DOI: 10.1007/7081_2017_204] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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11
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Tomberg A, De Cesco S, Huot M, Moitessier N. Solvent effect in diastereoselective intramolecular Diels–Alder reactions. Tetrahedron Lett 2015. [DOI: 10.1016/j.tetlet.2015.10.086] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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12
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Synthesis and alkylation of Aza-Gly-Pro building blocks of peptidomimetic libraries for developing prostaglandin F2α receptor modulators as therapeutics to inhibit preterm labor. Methods Mol Biol 2015. [PMID: 25616327 DOI: 10.1007/978-1-4939-2020-4_6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
Premature birth is a steadily increasing unmet medical need, for which new "tocolytic" agents are required to arrest contractions and delay labor. A peptide-based approach was developed to produce modulators of the prostaglandin F2α receptor as a novel target for tocolytic development. In this strategy, the solution-phase synthesis and alkylation of aza-glycyl-proline building blocks were key for the preparation of a series of modulators exhibiting biased signaling. An optimized method is now provided for making the aza-Gly-Pro unit with minimum side product, and alkylation of the unit is described to illustrate the library diversification step. Conditions have been reported for selectively unmasking the protecting groups at the N- and C-terminal of the aza-dipeptide unit and for its introduction into analogs that modulate the signaling of the PGF2α receptor. The merits of this protocol for azapeptide synthesis have thus been demonstrated by the synthesis of inhibitors of myometrial contraction exhibiting potential as prototypes for developing tocolytics to treat preterm labor.
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13
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Boukanoun MK, Hou X, Nikolajev L, Ratni S, Olson D, Claing A, Laporte SA, Chemtob S, Lubell WD. Investigation of the active turn geometry for the labour delaying activity of indolizidinone and azapeptide modulators of the prostaglandin F2α receptor. Org Biomol Chem 2015; 13:7750-61. [PMID: 26090777 DOI: 10.1039/c5ob00962f] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
On pursuing molecules that delay labour, so-called tocolytics, the prostaglandin F2α receptor (FP) was targeted, because of its role in the stimulation of uterine contractions leading to birth and preterm birth. Previously, both the indolizidinone PDC-113.824 (5) and the aza-glycinyl-proline analog 6 were shown to delay labour in mice by modulating the FP function, likely by an allosteric mechanism, which features biased signalling. The crystal structure and computational analyses of the indolizidin-2-one amino acid and aza-glycinyl-proline components of 5 and 6 in model peptides have shown them to adopt a geometry that mimics ideal type I and II'β-turns. To elucidate the precise turn geometry for receptor recognition, analogs 1-4 have now been synthesized: macrocycle and pyrroloazepinone mimics 1 and 2 to mimic type I, and glycinyl-proline and d-alaninyl-proline analogs 3 and 4 to favour type II'β-turn geometry. Notably, transannular cyclization of peptide macrocycle 13 has provided diastereoselectively pyrroloazepinone 15 by a novel route that provides effective access to mimics 1 and 2 by way of a common intermediate. Among the four analogs, none exhibited efficacy nor potency on par with 5 and 6; however, d-alaninyl-proline analog 4 proved superior to the other analogs in reducing PGF2α-induced myometrial contractions and inhibiting FP modulation of cell ruffling, a response dependent on the Gα12/RhoA/ROCK signaling pathway. Furthermore Gly-Pro analog 3 potentiated the effect of PGF2α on Gαq mediated ERK1/2 activation. Evidence that 4 adopted turn geometry was obtained by conformational analysis using NMR spectroscopy to characterize respectively the influence of solvent and temperature on the chemical shifts of the amide NH protons. Although mimicry of the type II' geometry by 3, 4, 5 and 6 may favour activity, distortion from ideal geometry by the indolizidinone and aza-glycinyl residues of the latter appears to enhance their biological effects.
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Affiliation(s)
- Meriem K Boukanoun
- Département de chimie, l'Université de Montréal, Montréal H3C 3J7, Canada.
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14
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Khashper A, Lubell WD. Design, synthesis, conformational analysis and application of indolizidin-2-one dipeptide mimics. Org Biomol Chem 2015; 12:5052-70. [PMID: 24899358 DOI: 10.1039/c4ob00777h] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Growth in the field of peptide mimicry over the past few decades has resulted in the synthesis of many new compounds and the investigation of novel pharmacological agents. Azabicyclo[X.Y.0]alkanone amino acids are among the attractive classes of constrained mimics, because they can create rigid peptide structures for probing the conformation and roles of natural motifs in recognition events important for biological activity. Herein, we review the last ten years of the synthesis, conformational analysis and activity of analogs of the azabicyclo[4.3.0]alkan-2-one amino acid subclass, so-called indolizidin-2-one amino acids, with particular attention on their employment as inputs for biological applications.
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Affiliation(s)
- Arkady Khashper
- Département de Chimie, Université de Montréal, Montréal H3C 3J7, Canada.
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15
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Sleno R, Pétrin D, Devost D, Goupil E, Zhang A, Hébert TE. Designing BRET-based conformational biosensors for G protein-coupled receptors. Methods 2015; 92:11-8. [PMID: 25962643 DOI: 10.1016/j.ymeth.2015.05.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Revised: 04/30/2015] [Accepted: 05/02/2015] [Indexed: 12/16/2022] Open
Abstract
Ligand-biased signaling is starting to have significant impact on drug discovery programs in the pharmaceutical industry and has reinvigorated our understanding of pharmacological efficacy. As such, many investigators and screening campaigns are now being directed at a larger section of the signaling responses downstream of an individual G protein-coupled receptor. Many biosensor-based platforms have been developed to capture signaling signatures. Despite our growing ability to use such signaling signatures, we remain hampered by the fact that signaling signatures may be particular to an individual cell type and thus our platforms may not be portable from cell to cell, necessitating further cell-specific biosensor development. Here, we provide a complementary strategy based on capturing receptor-proximal conformational profiles using intra-molecular BRET-based sensors composed of a Renilla luciferase donor engineered into the carboxy-terminus and CCPGCC motifs which bind fluorescent hairpin arsenical dyes engineered into different positions in intracellular loop 3 of FP, the receptor for PGF2α. We discuss the design and optimization of such sensors for orthosteric and allosteric ligands.
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Affiliation(s)
- Rory Sleno
- Department of Pharmacology and Therapeutics, McGill University, Canada
| | - Darlaine Pétrin
- Department of Pharmacology and Therapeutics, McGill University, Canada
| | - Dominic Devost
- Department of Pharmacology and Therapeutics, McGill University, Canada
| | - Eugénie Goupil
- Department of Pharmacology and Therapeutics, McGill University, Canada
| | - Alice Zhang
- Department of Pharmacology and Therapeutics, McGill University, Canada
| | - Terence E Hébert
- Department of Pharmacology and Therapeutics, McGill University, Canada.
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16
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Atmuri NDP, Lubell WD. Insight into Transannular Cyclization Reactions To Synthesize Azabicyclo[X.Y.Z]alkanone Amino Acid Derivatives from 8-, 9-, and 10-Membered Macrocyclic Dipeptide Lactams. J Org Chem 2015; 80:4904-18. [DOI: 10.1021/acs.joc.5b00237] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- N. D. Prasad Atmuri
- Département de Chimie, Université de Montréal, P.O. Box 6128, Station
Centre-ville, Montréal, Québec H3C 3J7, Canada
| | - William D. Lubell
- Département de Chimie, Université de Montréal, P.O. Box 6128, Station
Centre-ville, Montréal, Québec H3C 3J7, Canada
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17
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Goupil E, Fillion D, Clément S, Luo X, Devost D, Sleno R, Pétrin D, Saragovi HU, Thorin É, Laporte SA, Hébert TE. Angiotensin II type I and prostaglandin F2α receptors cooperatively modulate signaling in vascular smooth muscle cells. J Biol Chem 2014; 290:3137-48. [PMID: 25512374 DOI: 10.1074/jbc.m114.631119] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
The angiotensin II type I (AT1R) and the prostaglandin F2α (PGF2α) F prostanoid (FP) receptors are both potent regulators of blood pressure. Physiological interplay between AT1R and FP has been described. Abdominal aortic ring contraction experiments revealed that PGF2α-dependent activation of FP potentiated angiotensin II-induced contraction, whereas FP antagonists had the opposite effect. Similarly, PGF2α-mediated vasoconstriction was symmetrically regulated by co-treatment with AT1R agonist and antagonist. The underlying canonical Gαq signaling via production of inositol phosphates mediated by each receptor was also regulated by antagonists for the other receptor. However, binding to their respective agonists, regulation of receptor-mediated MAPK activation and vascular smooth muscle cell growth were differentially or asymmetrically regulated depending on how each of the two receptors were occupied by either agonist or antagonist. Physical interactions between these receptors have never been reported, and here we show that AT1R and FP form heterodimeric complexes in both HEK 293 and vascular smooth muscle cells. These findings imply that formation of the AT1R/FP dimer creates a novel allosteric signaling unit that shows symmetrical and asymmetrical signaling behavior, depending on the outcome measured. AT1R/FP dimers may thus be important in the regulation of blood pressure.
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Affiliation(s)
- Eugénie Goupil
- From the Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec H3G 1Y6
| | - Dany Fillion
- From the Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec H3G 1Y6
| | - Stéphanie Clément
- From the Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec H3G 1Y6
| | - Xiaoyan Luo
- the Centre de Recherche, Institut de Cardiologie de Montréal, Montréal, Québec H1T 1C8, Canada
| | - Dominic Devost
- From the Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec H3G 1Y6
| | - Rory Sleno
- From the Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec H3G 1Y6
| | - Darlaine Pétrin
- From the Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec H3G 1Y6
| | - H Uri Saragovi
- From the Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec H3G 1Y6, the Lady Davis Institute, Montréal Jewish General Hospital, Montréal, Québec H3T 1E2, and
| | - Éric Thorin
- the Centre de Recherche, Institut de Cardiologie de Montréal, Montréal, Québec H1T 1C8, Canada
| | - Stéphane A Laporte
- From the Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec H3G 1Y6, the Department of Medicine, McGill University Health Center Research Institute, Montréal, Québec H3A 2B2, the Department of Anatomy and Cell Biology, McGill University, Montréal, Québec H3A 0CT,
| | - Terence E Hébert
- From the Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec H3G 1Y6,
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18
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Bourguet CB, Claing A, Laporte SA, Hébert TE, Chemtob S, Lubell WD. Synthesis of azabicycloalkanone amino acid and azapeptide mimics and their application as modulators of the prostaglandin F2α receptor for delaying preterm birth. CAN J CHEM 2014. [DOI: 10.1139/cjc-2014-0289] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Premature birth (<37 weeks gestation) is the major cause of perinatal mortality and morbidity and has been steadily increasing worldwide. Towards the rational design of more effective therapeutic agents for inhibiting uterine contractions and prolonging gestation (a so-called tocolytic drug), our team has targeted the prostaglandin F2α receptor (FP) employing a peptidomimetic approach designed to provide modulators of this novel target. We identified first a lead peptide (PDC113) (1) based on the sequence of the second extracellular loop of FP on the basis that the loop itself might modulate receptor activation. Systematic study of the structure−activity relationships of 1 generated hypotheses concerning the conformation and side-chains responsible for activity that led to the synthesis of PDC113.31 (2), a potent all d-amino acid peptide, which has successfully completed Phase 1b clinical trials. Employing indolizidinone amino acids, peptide mimics were developed that served to probe the mechanism of FP modulation. For example, PDC113.824 (9) was shown to allosterically regulate FP activity contingent on the presence of prostaglandin F2α by a mechanism implicating biased signalling. Although attempts to understand the turn geometry responsible for the activity of 9 by replacement of its indolizidin-2-one moiety with other azabicycloalkanones failed to produce biologically active analogs, employment of aza-aminoacyl-proline analogs resulted in a series of FP modulators exhibiting distinct effects on different G protein-mediated signalling pathways. Our program has thus contributed novel probes for understanding the chemical biology of FP as well as new therapeutic agents with promise for inhibiting uterine contractions and preventing preterm birth.
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Affiliation(s)
- Carine B. Bourguet
- Département de Chimie, Université de Montréal, C.P.6128. Succursale Centre-Ville, Montréal, QC H3C 3J7, Canada
| | - Audrey Claing
- Département de Pharmacologie, Université de Montréal, C.P.6128. Succursale Centre-Ville, Montréal, QC H3C 3J7, Canada
| | - Stéphane A. Laporte
- Department of Medicine, McGill University Health Center Research Institute, Montréal, QC H3A 1A1, Canada
| | - Terence E. Hébert
- Department of Pharmacology and Therapeutics, McGill University, Montréal, QC H3G 1Y6, Canada
| | - Sylvain Chemtob
- Centre Hospitalier Universitaire Sainte-Justine Research Center, Montréal, QC H3T 1C5, Canada
| | - William D. Lubell
- Département de Chimie, Université de Montréal, C.P.6128. Succursale Centre-Ville, Montréal, QC H3C 3J7, Canada
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19
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Bourguet CB, Boulay PL, Claing A, Lubell WD. Design and synthesis of novel azapeptide activators of apoptosis mediated by caspase-9 in cancer cells. Bioorg Med Chem Lett 2014; 24:3361-5. [DOI: 10.1016/j.bmcl.2014.05.095] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Revised: 05/26/2014] [Accepted: 05/28/2014] [Indexed: 10/25/2022]
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20
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Garcia-Ramos Y, Lubell WD. Synthesis and alkylation of aza-glycinyl dipeptide building blocks. J Pept Sci 2013; 19:725-9. [DOI: 10.1002/psc.2572] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Revised: 09/12/2013] [Accepted: 09/14/2013] [Indexed: 11/05/2022]
Affiliation(s)
- Yesica Garcia-Ramos
- Département de Chimie; Université de Montréal; C.P. 6128, Succursale Centre-Ville Montreal Quebec H3C 3J7 Canada
| | - William D. Lubell
- Département de Chimie; Université de Montréal; C.P. 6128, Succursale Centre-Ville Montreal Quebec H3C 3J7 Canada
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21
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Abstract
G-protein–coupled receptors (GPCRs) still offer enormous scope for new therapeutic targets. Currently marketed agents are dominated by those with activity at aminergic receptors and yet they account for only ~10% of the family. Progress up until now with other subfamilies, notably orphans, Family A/peptide, Family A/lipid, Family B, Family C, and Family F, has been, at best, patchy. This may be attributable to the heterogeneous nature of GPCRs, their endogenous ligands, and consequently their binding sites. Our appreciation of receptor similarity has arguably been too simplistic, and screening collections have not necessarily been well suited to identifying leads in new areas. Despite the relative shortage of high-quality tool molecules in a number of cases, there is an emerging, and increasingly substantial, body of evidence associating many as yet “undrugged” receptors with a very wide range of diseases. Significant advances in our understanding of receptor pharmacology and technical advances in screening, protein X-ray crystallography, and ligand design methods are paving the way for new successes in the area. Exploitation of allosteric mechanisms; alternative signaling pathways such as G12/13, Gβγ, and β-arrestin; the discovery of “biased” ligands; and the emergence of GPCR-protein complexes as potential drug targets offer scope for new and much improved drugs.
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22
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Synthesis of multi-functionalized 1-azabicycles through MAOS acid catalyzed formal aza-[3+3] cycloaddition of heterocyclic enaminones with oxazolones. Tetrahedron Lett 2013. [DOI: 10.1016/j.tetlet.2013.04.055] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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23
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Jamieson AG, Boutard N, Sabatino D, Lubell WD. Peptide scanning for studying structure-activity relationships in drug discovery. Chem Biol Drug Des 2013; 81:148-65. [PMID: 23253136 DOI: 10.1111/cbdd.12042] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Peptide-based therapeutics have grown in importance over the last few decades. Furthermore, peptides have been extensively used as lead compounds in the drug discovery process to investigate the nature of chemical space required for molecular recognition and activity at a variety of targets. This critical commentary reviews scanning techniques, which employ natural and non-proteinogenic amino acids to facilitate understanding of structural requirements for peptide biological activity. The value of sequence analysis by such methods is highlighted by examples, in which the elements for peptide affinity and activity have been elucidated and employed to prepare peptidomimetic leads for drug development.
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Affiliation(s)
- Andrew G Jamieson
- Department of Chemistry, University of Leicester, Leicester LE1 7RH, UK
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24
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Guo CM, Kasaraneni N, Sun K, Myatt L. Cross talk between PKC and CREB in the induction of COX-2 by PGF2α in human amnion fibroblasts. Endocrinology 2012; 153:4938-45. [PMID: 22919060 PMCID: PMC3512005 DOI: 10.1210/en.2012-1441] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Compelling evidence indicates a crucial role of prostaglandin F2α (PGF2α) in parturition. Both the maternal and fetal sides of the fetal membranes synthesize PGF2α, which exerts effects via the prostaglandin F2α receptor (FP) that is coupled to the activation of protein kinase C (PKC). Cyclooxygenase-2 (COX-2) catalyzes the rate-limiting step of the inducible synthesis of prostaglandin. Although activation of PKC is known to induce COX-2 expression, it is not clear whether PGF2α can induce COX-2 via FP receptor-coupled PKC activation. COX-2 promoter carries a cAMP-response element (CRE) and phosphorylation of CRE binding protein 1 (CREB1) is associated with COX-2 expression in human amnion fibroblasts. We demonstrated that human amnion fibroblasts produced PGF2α and expressed FP receptor. PGF2α increased COX-2 expression and CREB1 phosphorylation, which could be blocked by either the FP receptor antagonist AL8810 or PKC inhibitor Ro31-7549. The PKC activator, phorbol-12-myristate-13-acetate (PMA), could mimic the induction of COX-2 and CREB1 phosphorylation. The induction of COX-2 by PGF2α and PMA could be attenuated by the small interfering RNA-mediated knockdown of CREB1 expression or overexpressing dominant-negative CREB1. A chromatin immunoprecipitation assay showed that the binding of CREB1 to the COX-2 promoter was increased by PGF2α and PMA in amnion fibroblasts. In conclusion, we provide evidence that PGF2α induces COX-2 expression via the FP receptor and phosphorylates CREB1 by PKC, thus increasing CREB1 binding to the COX-2 promoter and the expression of COX-2 in human amnion fibroblasts. This feed-forward loop may be crucial for the production of prostaglandins in the fetal membranes prior to the onset of labor.
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Affiliation(s)
- C M Guo
- School of Life Sciences, Fudan University, Shanghai 200433, People's Republic of China
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25
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Wu H, Amin MN, Niu Y, Qiao Q, Harfouch N, Nimer A, Cai J. Solid-phase synthesis of γ-AApeptides using a submonomeric approach. Org Lett 2012; 14:3446-9. [PMID: 22731678 DOI: 10.1021/ol301406a] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The solid-phase synthesis of γ-AApeptides using a novel submonomeric approach that utilizes an allyl protection is reported. The strategy successfully circumvents the necessity of preparing γ-AApeptide building blocks in order to prepare γ-AApeptide sequences. This method will maximize the potential of developing chemically diverse γ-AApeptide libraries and thereby facilitate the biological applications of γ-AApeptides in the future.
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Affiliation(s)
- Haifan Wu
- Department of Chemistry, University of South Florida, Tampa, Florida 33620, USA
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