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Shpakov AO. Allosteric Regulation of G-Protein-Coupled Receptors: From Diversity of Molecular Mechanisms to Multiple Allosteric Sites and Their Ligands. Int J Mol Sci 2023; 24:6187. [PMID: 37047169 PMCID: PMC10094638 DOI: 10.3390/ijms24076187] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 03/21/2023] [Accepted: 03/23/2023] [Indexed: 03/29/2023] Open
Abstract
Allosteric regulation is critical for the functioning of G protein-coupled receptors (GPCRs) and their signaling pathways. Endogenous allosteric regulators of GPCRs are simple ions, various biomolecules, and protein components of GPCR signaling (G proteins and β-arrestins). The stability and functional activity of GPCR complexes is also due to multicenter allosteric interactions between protomers. The complexity of allosteric effects caused by numerous regulators differing in structure, availability, and mechanisms of action predetermines the multiplicity and different topology of allosteric sites in GPCRs. These sites can be localized in extracellular loops; inside the transmembrane tunnel and in its upper and lower vestibules; in cytoplasmic loops; and on the outer, membrane-contacting surface of the transmembrane domain. They are involved in the regulation of basal and orthosteric agonist-stimulated receptor activity, biased agonism, GPCR-complex formation, and endocytosis. They are targets for a large number of synthetic allosteric regulators and modulators, including those constructed using molecular docking. The review is devoted to the principles and mechanisms of GPCRs allosteric regulation, the multiplicity of allosteric sites and their topology, and the endogenous and synthetic allosteric regulators, including autoantibodies and pepducins. The allosteric regulation of chemokine receptors, proteinase-activated receptors, thyroid-stimulating and luteinizing hormone receptors, and beta-adrenergic receptors are described in more detail.
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Affiliation(s)
- Alexander O Shpakov
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, 194223 St. Petersburg, Russia
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Alfei S, Zuccari G, Russo E, Villa C, Brullo C. Hydrogel Formulations of Antibacterial Pyrazoles Using a Synthesized Polystyrene-Based Cationic Resin as a Gelling Agent. Int J Mol Sci 2023; 24:ijms24021109. [PMID: 36674627 PMCID: PMC9862678 DOI: 10.3390/ijms24021109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 12/29/2022] [Accepted: 01/03/2023] [Indexed: 01/09/2023] Open
Abstract
Here, to develop new topical antibacterial formulations to treat staphylococcal infections, two pyrazoles (3c and 4b) previously reported as antibacterial agents, especially against staphylococci, were formulated as hydrogels (R1-HG-3c and R1HG-4b) using a cationic polystyrene-based resin (R1) and here synthetized and characterized as gelling agents. Thanks to the high hydrophilicity, high-level porosity, and excellent swelling capabilities of R1, R1HG-3c and R1HG-4b were achieved with an equilibrium degree of swelling (EDS) of 765% (R1HG-3c) and 675% (R1HG-4b) and equilibrium water content (EWC) of 88% and 87%, respectively. The chemical structure of soaked and dried gels was investigated by PCA-assisted attenuated total reflectance (ATR) Fourier transform infrared (FTIR) spectroscopy, while their morphology was investigated by optical microscopy. Weight loss studies were carried out with R1HG-3c and R1HG-4b to investigate their water release profiles and the related kinetics, while their stability was evaluated over time both by monitoring their inversion properties to detect possible impairments of the 3D network and by PCA-assisted ATR-FTIR spectroscopy to detect possible structural changes. The flow and dynamic rheological characterization of the gels was assessed by determining their viscosity vs. shear rate, applying the Cross rheological equation to achieve the curves of shear stress vs. shear rate, and carrying out amplitude and frequency sweep experiments. Finally, their content in NH3+ groups was determined by potentiometric titrations. Due to their favorable physicochemical characteristic and the antibacterial effects of 3c and 4b possibly improved by the cationic R1, the pyrazole-enriched gels reported here could represent new weapons to treat severe skin and wound infections sustained by MDR bacteria of staphylococcal species.
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Affiliation(s)
- Silvana Alfei
- Department of Pharmacy, Section of Chemistry and Pharmaceutical and Food Technologies, University of Genoa, Viale Cembrano, 4, 16148 Genoa, Italy
- Correspondence: (S.A.); (G.Z.); Tel.: +39-010-355-2296 (S.A.)
| | - Guendalina Zuccari
- Department of Pharmacy, Section of Chemistry and Pharmaceutical and Food Technologies, University of Genoa, Viale Cembrano, 4, 16148 Genoa, Italy
- Correspondence: (S.A.); (G.Z.); Tel.: +39-010-355-2296 (S.A.)
| | - Eleonora Russo
- Department of Pharmacy (DIFAR), Section of Medicinal Chemistry and Cosmetic Product, University of Genoa, Viale Benedetto XV, 3, 16132 Genoa, Italy
| | - Carla Villa
- Department of Pharmacy (DIFAR), Section of Medicinal Chemistry and Cosmetic Product, University of Genoa, Viale Benedetto XV, 3, 16132 Genoa, Italy
| | - Chiara Brullo
- Department of Pharmacy (DIFAR), Section of Medicinal Chemistry and Cosmetic Product, University of Genoa, Viale Benedetto XV, 3, 16132 Genoa, Italy
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Ma H, Sun Z, Liu J, Zhang X, Cui H, Zhang Y, Wang J. CBr4-Mediated Intermolecular Cyclization Reaction: Efficient Synthesis of Substituted N-Acylpyrazoles. CHINESE J ORG CHEM 2021. [DOI: 10.6023/cjoc202107020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Comparative Study of the Steroidogenic Effects of Human Chorionic Gonadotropin and Thieno[2,3-D]pyrimidine-Based Allosteric Agonist of Luteinizing Hormone Receptor in Young Adult, Aging and Diabetic Male Rats. Int J Mol Sci 2020; 21:ijms21207493. [PMID: 33050653 PMCID: PMC7590010 DOI: 10.3390/ijms21207493] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 10/05/2020] [Accepted: 10/07/2020] [Indexed: 12/16/2022] Open
Abstract
Low-molecular-weight agonists of luteinizing hormone (LH)/human chorionic gonadotropin (hCG) receptor (LHCGR), which interact with LHCGR transmembrane allosteric site and, in comparison with gonadotropins, more selectively activate intracellular effectors, are currently being developed. Meanwhile, their effects on testicular steroidogenesis have not been studied. The purpose of this work is to perform a comparative study of the effects of 5-amino-N-tert-butyl-4-(3-(1-methylpyrazole-4-carboxamido)phenyl)-2-(methylthio)thieno[2,3-d] pyrimidine-6-carboxamide (TP4/2), a LHCGR allosteric agonist developed by us, and hCG on adenylyl cyclase activity in rat testicular membranes, testosterone levels, testicular steroidogenesis and spermatogenesis in young (four-month-old), aging (18-month-old) and diabetic male Wistar rats. Type 1 diabetes was caused by a single streptozotocin (50 mg/kg) injection. TP4/2 (20 mg/kg/day) and hCG (20 IU/rat/day) were administered for 5 days. TP4/2 was less effective in adenylyl cyclase stimulation and ability to activate steroidogenesis when administered once into rats. On the 3rd–5th day, TP4/2 and hCG steroidogenic effects in young adult, aging and diabetic rats were comparable. Unlike hCG, TP4/2 did not inhibit LHCGR gene expression and did not hyperstimulate the testicular steroidogenesis system, moderately increasing steroidogenic proteins gene expression and testosterone production. In aging and diabetic testes, TP4/2 improved spermatogenesis. Thus, during five-day administration, TP4/2 steadily stimulates testicular steroidogenesis, and can be used to prevent androgen deficiency in aging and diabetes.
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Anderson RC, Newton CL, Anderson RA, Millar RP. Gonadotropins and Their Analogs: Current and Potential Clinical Applications. Endocr Rev 2018; 39:911-937. [PMID: 29982442 DOI: 10.1210/er.2018-00052] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Accepted: 06/25/2018] [Indexed: 12/15/2022]
Abstract
The gonadotropin receptors LH receptor and FSH receptor play a central role in governing reproductive competency/fertility. Gonadotropin hormone analogs have been used clinically for decades in assisted reproductive therapies and in the treatment of various infertility disorders. Though these treatments are effective, the clinical protocols demand multiple injections, and the hormone preparations can lack uniformity and stability. The past two decades have seen a drive to develop chimeric and modified peptide analogs with more desirable pharmacokinetic profiles, with some displaying clinical efficacy, such as corifollitropin alfa, which is now in clinical use. More recently, low-molecular-weight, orally active molecules with activity at gonadotropin receptors have been developed. Some have excellent characteristics in animals and in human studies but have not reached the market-largely as a result of acquisitions by large pharma. Nonetheless, such molecules have the potential to mitigate risks currently associated with gonadotropin-based fertility treatments, such as ovarian hyperstimulation syndrome and the demands of injection-based therapies. There is also scope for novel use beyond the current remit of gonadotropin analogs in fertility treatments, including application as novel contraceptives; in the treatment of polycystic ovary syndrome; in the restoration of function to inactivating mutations of gonadotropin receptors; in the treatment of ovarian and prostate cancers; and in the prevention of bone loss and weight gain in postmenopausal women. Here we review the properties and clinical application of current gonadotropin preparations and their analogs, as well as the development of novel orally active, small-molecule nonpeptide analogs.
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Affiliation(s)
- Ross C Anderson
- Centre for Neuroendocrinology, University of Pretoria, Pretoria, South Africa.,Department of Physiology, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa
| | - Claire L Newton
- Centre for Neuroendocrinology, University of Pretoria, Pretoria, South Africa.,Department of Immunology, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa
| | - Richard A Anderson
- MRC Centre for Reproductive Health, The Queen's Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Robert P Millar
- Centre for Neuroendocrinology, University of Pretoria, Pretoria, South Africa.,Department of Physiology, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.,Department of Immunology, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.,Department of Integrative Biomedical Sciences, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.,Institute of Infectious Diseases and Molecular Medicine, University of Cape Town, Cape Town, South Africa
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Abstract
Gonadotropin receptors include the follicle stimulating hormone receptor (FSHR) and the luteinizing hormone/choriogonadotropin receptor (LHCGR), both belong to the G protein-coupled receptor (GPCR) superfamily and are essential to reproduction. FSHR is activated by follicle stimulating hormone (FSH) while LHCGR is activated by either luteinizing hormone (LH) or choriogonadotropin (CG). Upon ligand binding, gonadotropin receptors undergo conformational changes that lead to the activation of the heterotrimeric G protein, resulting in the production of different second messengers. Gonadotropin receptors can also recruit and bind β-arrestins. This particular class of scaffold proteins were initially identified to mediate GPCRs desensitization and recycling, but it is now well established that β-arrestins can also initiate Gs-independent signaling by assembling signaling modules. Furthermore, new advances in structural biology and biophysical techniques have revealed novel activation mechanisms allowing β-arrestins and G proteins to control signaling in time and space. The ability of different ligands to preferentially elicit G- or β-arrestin-mediated signaling is known as functional selectivity or biased signaling. This new concept has switched the view of pharmacology efficacy from monodimensional to multidimensional. Biased signaling offers the possibility to separate therapeutic benefits of a drug from its adverse effects. The proof of concept that gonadotropin receptors can be subjected to biased signaling is now established. The challenge will now be the design of molecules that can specifically activate beneficial signaling pathway at gonadotropin receptors while reducing or abolishing those leading to side effects. Such strategy could for instance lead to improved treatments for infertility.
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Affiliation(s)
| | - Eric Reiter
- PCR, INRA, CNRS, IFCE, Université de Tours, Nouzilly, France -
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Ayoub MA, Yvinec R, Jégot G, Dias JA, Poli SM, Poupon A, Crépieux P, Reiter E. Profiling of FSHR negative allosteric modulators on LH/CGR reveals biased antagonism with implications in steroidogenesis. Mol Cell Endocrinol 2016; 436:10-22. [PMID: 27424143 DOI: 10.1016/j.mce.2016.07.013] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 07/09/2016] [Accepted: 07/10/2016] [Indexed: 01/14/2023]
Abstract
Biased signaling has recently emerged as an interesting means to modulate the function of many G protein-coupled receptors (GPCRs). Previous studies reported two negative allosteric modulators (NAMs) of follicle-stimulating hormone receptor (FSHR), ADX68692 and ADX68693, with differential effects on FSHR-mediated steroidogenesis and ovulation. In this study, we attempted to pharmacologically profile these NAMs on the closely related luteinizing hormone/chorionic gonadotropin hormone receptor (LH/CGR) with regards to its canonical Gs/cAMP pathway as well as to β-arrestin recruitment in HEK293 cells. The NAMs' effects on cAMP, progesterone and testosterone production were also assessed in murine Leydig tumor cell line (mLTC-1) as well as rat primary Leydig cells. We found that both NAMs strongly antagonized LH/CGR signaling in the different cell models used with ADX68693 being more potent than ADX68692 to inhibit hCG-induced cAMP production in HEK293, mLTC-1 and rat primary Leydig cells as well as β-arrestin 2 recruitment in HEK293 cells. Interestingly, differential antagonism of the two NAMs on hCG-promoted steroidogenesis in mLTC-1 and rat primary Leydig cells was observed. Indeed, a significant inhibition of testosterone production by the two NAMs was observed in both cell types, whereas progesterone production was only inhibited by ADX68693 in rat primary Leydig cells. In addition, while ADX68693 totally abolished testosterone production, ADX68692 had only a partial effect in both mLTC-1 and rat primary Leydig cells. These observations suggest biased effects of the two NAMs on LH/CGR-dependent pathways controlling steroidogenesis. Interestingly, the pharmacological profiles of the two NAMs with respect to steroidogenesis were found to differ from that previously shown on FSHR. This illustrates the complexity of signaling pathways controlling FSHR- and LH/CGR-mediated steroidogenesis, suggesting differential implication of cAMP and β-arrestins mediated by FSHR and LH/CGR. Together, our data demonstrate that ADX68692 and ADX68693 are biased NAMs at the LH/CGR in addition to the FSHR. These pharmacological characteristics are important to consider for potential contraceptive and therapeutic applications based on such compounds.
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Affiliation(s)
- Mohammed Akli Ayoub
- PRC, INRA, CNRS, IFCE, Université de Tours, 37380, Nouzilly, France; LE STUDIUM(®) Loire Valley Institute for Advanced Studies, 45000, Orléans, France.
| | - Romain Yvinec
- PRC, INRA, CNRS, IFCE, Université de Tours, 37380, Nouzilly, France
| | - Gwenhaël Jégot
- PRC, INRA, CNRS, IFCE, Université de Tours, 37380, Nouzilly, France
| | - James A Dias
- Department of Biomedical Sciences, State University of New York at Albany, Albany, NY, USA
| | | | - Anne Poupon
- PRC, INRA, CNRS, IFCE, Université de Tours, 37380, Nouzilly, France
| | - Pascale Crépieux
- PRC, INRA, CNRS, IFCE, Université de Tours, 37380, Nouzilly, France
| | - Eric Reiter
- PRC, INRA, CNRS, IFCE, Université de Tours, 37380, Nouzilly, France
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Nataraja SG, Yu HN, Palmer SS. Discovery and Development of Small Molecule Allosteric Modulators of Glycoprotein Hormone Receptors. Front Endocrinol (Lausanne) 2015; 6:142. [PMID: 26441832 PMCID: PMC4568768 DOI: 10.3389/fendo.2015.00142] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 08/31/2015] [Indexed: 11/30/2022] Open
Abstract
Glycoprotein hormones, follicle-stimulating hormone (FSH), luteinizing hormone (LH), and thyroid-stimulating hormone (TSH) are heterodimeric proteins with a common α-subunit and hormone-specific β-subunit. These hormones are dominant regulators of reproduction and metabolic processes. Receptors for the glycoprotein hormones belong to the family of G protein-coupled receptors. FSH receptor (FSHR) and LH receptor are primarily expressed in somatic cells in ovary and testis to promote egg and sperm production in women and men, respectively. TSH receptor is expressed in thyroid cells and regulates the secretion of T3 and T4. Glycoprotein hormones bind to the large extracellular domain of the receptor and cause a conformational change in the receptor that leads to activation of more than one intracellular signaling pathway. Several small molecules have been described to activate/inhibit glycoprotein hormone receptors through allosteric sites of the receptor. Small molecule allosteric modulators have the potential to be administered orally to patients, thus improving the convenience of treatment. It has been a challenge to develop a small molecule allosteric agonist for glycoprotein hormones that can mimic the agonistic effects of the large natural ligand to activate similar signaling pathways. However, in the past few years, there have been several promising reports describing distinct chemical series with improved potency in preclinical models. In parallel, proposal of new structural model for FSHR and in silico docking studies of small molecule ligands to glycoprotein hormone receptors provide a giant leap on the understanding of the mechanism of action of the natural ligands and new chemical entities on the receptors. This review will focus on the current status of small molecule allosteric modulators of glycoprotein hormone receptors, their effects on common signaling pathways in cells, their utility for clinical application as demonstrated in preclinical models, and use of these molecules as novel tools to dissect the molecular signaling pathways of these receptors.
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Affiliation(s)
- Selvaraj G. Nataraja
- TocopheRx Inc., Burlington, MA, USA
- *Correspondence: Selvaraj G. Nataraja, TocopheRx Inc., 15 New England Executive Park, Suite 1087, Burlington, MA 01803, USA,
| | - Henry N. Yu
- TocopheRx Inc., Burlington, MA, USA
- EMD Serono Research and Development Institute Inc., Billerica, MA, USA
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Handelsman DJ, Idan A, Grainger J, Goebel C, Turner L, Conway AJ. Detection and effects on serum and urine steroid and LH of repeated GnRH analog (leuprolide) stimulation. J Steroid Biochem Mol Biol 2014; 141:113-20. [PMID: 24495617 DOI: 10.1016/j.jsbmb.2014.01.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Revised: 01/21/2014] [Accepted: 01/27/2014] [Indexed: 12/14/2022]
Abstract
Non-steroidal drugs that increase endogenous testosterone (T) may be used to exploit ergogenic effects of androgens in power sports. While superactive GnRH analog use is suspected, neither screening nor detection tests are developed. This study aimed to determine if (a) stimulation for 5 days by leuprolide (a superactive GnRH analog) of serum and urine steroids and urine LH is reproducible at a 2 week interval, (b) nandrolone decanoate (ND) co-administration masks responses to leuprolide administration, (c) performance of urine measurement of leuprolide and M1, its major metabolite, as a detection test. Healthy men were randomized into a 4 week parallel group, open label clinical study in which all men had daily sc injections of leuprolide (1mg) for 4 days in the 1st and 3rd weeks with hormone-free 2nd and 4th weeks. In the 3rd week, men were randomized to either ND injections or no extra treatment. Serum steroids were determined by liquid chromatography, tandem mass spectrometry (LC-MS), urine steroids by gas chromatography, mass spectrometry (GC-MS), urine leuprolide and M1 by high resolution LC-MS and urine LH by immunoassay. Leuprolide stimulated striking, reproducible increases in serum and urine LH and steroids (serum T, dihydroT (DHT), 3α diol; urine T, epitestosterone (E) and androsterone (A). ND suppressed basal serum T, E2, 3α diol, and urinary E but did not mask or change the magnitude of responses to leuprolide. Urine leuprolide and M1 measurement had 100% sensitivity and specificity in detecting leuprolide administration up to one day after cessation of injections with the detection window between 1 and 3 days after last dose. Screening using urine steroid and LH measurements, optimally by urinary log10(LHxT), correctly classified 82% of urine samples. It is concluded that leuprolide stimulation of endogenous testosterone is reproducible after a 10-day interval, is not masked by ND and is reliably detected by urine leuprolide or M1 measurement for at least 1 day after administration.
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Affiliation(s)
- David J Handelsman
- Andrology Department, Concord Hospital, Sydney, NSW 2139, Australia; ANZAC Research Institute, University of Sydney, Sydney, NSW 2139, Australia.
| | - Amanda Idan
- Andrology Department, Concord Hospital, Sydney, NSW 2139, Australia
| | - Janelle Grainger
- Australian Sports Drug Testing Laboratory, National Measurement Institute, Sydney, NSW 2139, Australia
| | - Catrin Goebel
- Australian Sports Drug Testing Laboratory, National Measurement Institute, Sydney, NSW 2139, Australia
| | - Leo Turner
- Andrology Department, Concord Hospital, Sydney, NSW 2139, Australia
| | - Ann J Conway
- Andrology Department, Concord Hospital, Sydney, NSW 2139, Australia; ANZAC Research Institute, University of Sydney, Sydney, NSW 2139, Australia
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Yu HN, Richardson TE, Nataraja S, Fischer DJ, Sriraman V, Jiang X, Bharathi P, Foglesong RJ, Haxell TF, Heasley BH, Jenks M, Li J, Dugas MS, Collis R, Tian H, Palmer S, Goutopoulos A. Discovery of substituted benzamides as follicle stimulating hormone receptor allosteric modulators. Bioorg Med Chem Lett 2014; 24:2168-72. [DOI: 10.1016/j.bmcl.2014.03.018] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2014] [Revised: 03/06/2014] [Accepted: 03/10/2014] [Indexed: 12/31/2022]
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Shyam Sunder K, Maleraju J. Synthesis of novel N-(3-chloro-4-flurophenyl)-2-(5-((3-(4-hydroxy-2, 2-dimethyl-2, 3-dihydrobenzofuran-5-yl)-1-phenyl-1H-pyrazol-4-yl) methylene)-4-oxo-2-thioxothiazolidin-3-yl) acetamides having anti-inflammatory activity. ACTA ACUST UNITED AC 2013. [DOI: 10.1016/j.dit.2013.07.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Allosteric modulators of rhodopsin-like G protein-coupled receptors: opportunities in drug development. Pharmacol Ther 2012; 135:292-315. [PMID: 22728155 DOI: 10.1016/j.pharmthera.2012.06.002] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Accepted: 06/07/2012] [Indexed: 11/21/2022]
Abstract
Rhodopsin-like (class A) G protein-coupled receptors (GPCRs) are one of the most important classes of drug targets. The discovery that these GPCRs can be allosterically modulated by small drug molecules has opened up new opportunities in drug development. It will allow the drugability of "difficult targets", such as GPCRs activated by large (glyco)proteins, or by very polar or highly lipophilic physiological agonists. Receptor subtype selectivity should be more easily achievable with allosteric than with orthosteric ligands. Allosteric modulation will allow a broad spectrum of pharmacological effects largely expanding that of orthosteric ligands. Furthermore, allosteric modulators may show an improved safety profile as compared to orthosteric ligands. Only recently, the explicit search for allosteric modulators has been started for only a few rhodopsin-like GPCRs. The first negative allosteric modulators (allosteric antagonists) of chemokine receptors, maraviroc (CCR5 receptor), used in HIV therapy, and plerixafor (CXCR4 receptor) for stem cell mobilization, have been approved as drugs. The development of allosteric modulators for rhodopsin-like GPCRs as novel drugs is still at an early stage; it appears highly promising.
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Goebel C. Stimulating luteinizing hormone. Drug Test Anal 2011; 3:868-72. [DOI: 10.1002/dta.393] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2011] [Revised: 10/25/2011] [Accepted: 10/25/2011] [Indexed: 11/08/2022]
Affiliation(s)
- Catrin Goebel
- National Measurement Institute; Pymble; NSW; Australia
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Ulloa-Aguirre A, Crépieux P, Poupon A, Maurel MC, Reiter E. Novel pathways in gonadotropin receptor signaling and biased agonism. Rev Endocr Metab Disord 2011; 12:259-74. [PMID: 21526415 DOI: 10.1007/s11154-011-9176-2] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Gonadotropins play a central role in the control of male and female reproduction. Selective agonists and antagonists of gonadotropin receptors would be of great interest for the treatment of infertility or as non steroidal contraceptive. However, to date, only native hormones are being used in assisted reproduction technologies as there is no pharmacological agent available to manipulate gonadotropin receptors. Over the last decade, there has been a growing perception of the complexity associated with gonadotropin receptors' cellular signaling. It is now clear that the Gs/cAMP/PKA pathway is not the sole mechanism that must be taken into account in order to understand these hormones' biological actions. In parallel, consistent with the emerging paradigm of biased agonism, several examples of ligand-mediated selective signaling pathway activation by gonadotropin receptors have been reported. Small molecule ligands, modulating antibodies interacting with the hormones and glycosylation variants of the native glycoproteins have all demonstrated their potential to trigger such selective signaling. Altogether, the available data and emerging concepts give rise to intriguing opportunities towards a more efficient control of reproductive function and associated disorders.
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Affiliation(s)
- Alfredo Ulloa-Aguirre
- BIOS group, INRA, UMR85, Unité Physiologie de la Reproduction et des Comportements, 37380 Nouzilly, France.
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Arey BJ, López FJ. Are circulating gonadotropin isoforms naturally occurring biased agonists? Basic and therapeutic implications. Rev Endocr Metab Disord 2011; 12:275-88. [PMID: 21706143 DOI: 10.1007/s11154-011-9188-y] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The gonadotropins, luteinizing hormone, human chorionic gonadotropin and follicle-stimulating hormone, are key regulators of reproduction. As a result of this function, they have been the focus of research for many years. Isolated or recombinant proteins have been successfully used therapeutically for the treatment of infertility; and, in the case of compounds that block gonadotropin activity, for their potential utility in contraception. Until recently, selective small molecules modulating gonadotropin receptor activity have proven difficult to identify. The gonadotropins are glycoproteins that are released into the plasma as differently glycosylated isoforms and bind to specific G protein-coupled receptors. The degree of glycosylation on the gonadotropins has been shown to be important for the biological activities of these hormones and is differentially regulated depending on the steroidal status. Recent data from the study of glycosylated variants of LH, hCG and FSH have revealed that these isoforms have distinct signaling properties that allow for gonadotropin pleiotropic signals to be transduced effectively at the level of the receptor. Thus, glycosylated variants of the gonadotropins behave as biased agonists. Recently, newly developed, small molecule, synthetic allosteric compounds have been identified that are capable of mimicking this biased signaling. This opens the door to development of orally available, drug-like therapies for reproductive disorders that offer similar pleiotropic richness as that offered by the complex, endogenous hormones.
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Affiliation(s)
- Brian J Arey
- Metabolic and Cardiovascular Drug Discovery, Research and Development, Bristol-Myers Squibb Co., 311 Pennington-Rocky Hill Rd., Mail Stop- 21-1.08, Hopewell, NJ 08543, USA.
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Kidwai M, Jain A, Poddar R. Zn[(l)proline]2 in water: A new easily accessible and recyclable catalytic system for the synthesis of pyrazoles. J Organomet Chem 2011. [DOI: 10.1016/j.jorganchem.2010.09.012] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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17
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Shpakov AO, Shpakova EA. [Low-molecular regulators of polypeptide hormones receptors containing LGR repeats]. BIOMEDIT︠S︡INSKAI︠A︡ KHIMII︠A︡ 2010; 56:303-18. [PMID: 20695210 DOI: 10.18097/pbmc20105603303] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
During the last years the low-molecular non-peptidic regulators of the polypeptide hormones receptors containing LGR-repeats were identified. In the review the data on the structure and the molecular mechanisms of action of these regulators as agonists and antagonists of the luteinizing, follicle-stimulating and thyrotropin hormones are analyzed and systematized. The regulators interact with the serpentine domain of LGR-receptor and trigger the signaling cascades coupled with the receptor. Low-molecular agonists and antagonists of the LGR-receptors are considered as a new generation of the drugs that regulates the functional activity of sensitive to pituitary glycoprotein hormones signaling systems with high efficiency and selectivity. These regulators are more accessible compared to the hormones and can be use orally.
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Shpakov AO, Shpakova EA. Low-molecular regulators of polypeptide hormone receptors containing LGR-repeats. BIOCHEMISTRY (MOSCOW) SUPPLEMENT SERIES B: BIOMEDICAL CHEMISTRY 2009. [DOI: 10.1134/s1990750809040040] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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19
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Neumann S, Raaka BM, Gershengorn MC. Human TSH receptor ligands as pharmacological probes with potential clinical application. Expert Rev Endocrinol Metab 2009; 4:669. [PMID: 20161662 PMCID: PMC2819035 DOI: 10.1586/eem.09.36] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The biologic role of thyroid-stimulating hormone (TSH; thyrotropin) as an activator (agonist) of the TSH receptor (TSHR) in the hypothalamic-pituitary-thyroid axis is well known and activation of TSHR by recombinant human TSH is used clinically in patients with thyroid cancer. TSHR ligands other than TSH could be used to probe TSHR biology in thyroidal and extrathyroidal tissues, and potentially be employed in patients. A number of different TSHR ligands have been reported, including TSH analogs, antibodies and small-molecule, drug-like compounds. In this review, we will provide an update on all these classes of TSHR agonists and antagonists but place emphasis on small-molecule ligands.
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Affiliation(s)
- Susanne Neumann
- Clinical Endocrinology Branch, NIDDK, NIH, 50 South Drive, Bethesda, MD 20892-28029, USA, Tel.: +1 301 451 6324, Fax: +1 301 480 4214
| | - Bruce M Raaka
- Clinical Endocrinology Branch, NIDDK, NIH, 50 South Drive, Bethesda, MD 20892-28029, USA, Tel.: +1 301 451 6307, Fax: +1 301 480 4214
| | - Marvin C Gershengorn
- Author for correspondence: Clinical Endocrinology Branch, NIDDK, NIH, 50 South Drive, Bethesda, MD 20892-28029, USA, Tel.: +1 301 451 6305, Fax: +1 301 480 4214,
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Abstract
Two major functions of the mammalian ovary are the production of germ cells (oocytes), which allow continuation of the species, and the generation of bioactive molecules, primarily steroids (mainly estrogens and progestins) and peptide growth factors, which are critical for ovarian function, regulation of the hypothalamic-pituitary-ovarian axis, and development of secondary sex characteristics. The female germline is created during embryogenesis when the precursors of primordial germ cells differentiate from somatic lineages of the embryo and take a unique route to reach the urogenital ridge. This undifferentiated gonad will differentiate along a female pathway, and the newly formed oocytes will proliferate and subsequently enter meiosis. At this point, the oocyte has two alternative fates: die, a common destiny of millions of oocytes, or be fertilized, a fate of at most approximately 100 oocytes, depending on the species. At every step from germline development and ovary formation to oogenesis and ovarian development and differentiation, there are coordinated interactions of hundreds of proteins and small RNAs. These studies have helped reproductive biologists to understand not only the normal functioning of the ovary but also the pathophysiology and genetics of diseases such as infertility and ovarian cancer. Over the last two decades, parallel progress has been made in the assisted reproductive technology clinic including better hormonal preparations, prenatal genetic testing, and optimal oocyte and embryo analysis and cryopreservation. Clearly, we have learned much about the mammalian ovary and manipulating its most important cargo, the oocyte, since the birth of Louise Brown over 30 yr ago.
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Affiliation(s)
- Mark A Edson
- Department of Pathology, Baylor College of Medicine, One Baylor Plaza, Houston, Texas 77030, USA
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Small-molecule agonists for the thyrotropin receptor stimulate thyroid function in human thyrocytes and mice. Proc Natl Acad Sci U S A 2009; 106:12471-6. [PMID: 19592511 DOI: 10.1073/pnas.0904506106] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Seven-transmembrane-spanning receptors (7TMRs) are prominent drug targets. However, small-molecule ligands for 7-transmembrane-spanning receptors for which the natural ligands are large, heterodimeric glycoprotein hormones, like thyroid-stimulating hormone (TSH; thyrotropin), have only recently been reported, and none are approved for human use. We have used quantitative high-throughput screening to identify a small-molecule TSH receptor (TSHR) agonist that was modified to produce a second agonist with increased potency. We show that these agonists are highly selective for human TSHR versus other glycoprotein hormone receptors and interact with the receptor's serpentine domain. A binding pocket within the transmembrane domain was defined by docking into a TSHR homology model and was supported by site-directed mutagenesis. In primary cultures of human thyrocytes, both TSH and the agonists increase mRNA levels for thyroglobulin, thyroperoxidase, sodium iodide symporter, and deiodinase type 2, and deiodinase type 2 enzyme activity. Moreover, oral administration of the agonist stimulated thyroid function in mice, resulting in increased serum thyroxine and thyroidal radioiodide uptake. Thus, we discovered a small molecule that activates human TSHR in vitro, is orally active in mice, and could be a lead for development of drugs to use in place of recombinant human TSH in patients with thyroid cancer.
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Harju K, Vesterinen J, Yli-Kauhaluoma J. Solid-Phase Synthesis of Amino Acid Derived N-Unsubstituted Pyrazoles via Sydnones. Org Lett 2009; 11:2219-21. [DOI: 10.1021/ol900704b] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Kirsi Harju
- Division of Pharmaceutical Chemistry, Faculty of Pharmacy, P.O. Box 56, FI-00014 University of Helsinki, Finland
| | - Johanna Vesterinen
- Division of Pharmaceutical Chemistry, Faculty of Pharmacy, P.O. Box 56, FI-00014 University of Helsinki, Finland
| | - Jari Yli-Kauhaluoma
- Division of Pharmaceutical Chemistry, Faculty of Pharmacy, P.O. Box 56, FI-00014 University of Helsinki, Finland
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23
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van Straten N, Timmers M. Chapter 8 Non-Peptide Ligands for the Gonadotropin Receptors. ANNUAL REPORTS IN MEDICINAL CHEMISTRY 2009. [DOI: 10.1016/s0065-7743(09)04408-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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Heitman LH, Ijzerman AP. G protein-coupled receptors of the hypothalamic-pituitary-gonadal axis: a case for Gnrh, LH, FSH, and GPR54 receptor ligands. Med Res Rev 2008; 28:975-1011. [PMID: 18561294 DOI: 10.1002/med.20129] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The hypothalamic-pituitary-gonadal (HPG) axis, important in reproduction and sex hormone-dependent diseases, is regulated by a number of G protein-coupled receptors. The recently "deorphanized" GPR54 receptor activated by the peptide metastin is thought to be the key regulator of the axis, mainly by releasing gonadotropin-releasing hormone (GnRH) from the hypothalamus. The latter decapeptide, through the activation of the GnRH receptor in the anterior pituitary, causes the secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH), which subsequently activate their respective receptors on the gonadotrope cells. In this review we will discuss the small molecule agonists and antagonists that are currently being developed to intervene with the action of these four receptors. For GnRH receptors, 14 different chemical classes of non-peptidic antagonists have been reported, while for the LH receptor three classes of agonists have been described. Both agonists and antagonists have been introduced for the FSH receptor. Recently, the first non-peptidic agonist for GPR54 was reported.
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Affiliation(s)
- Laura H Heitman
- Division of Medicinal Chemistry, Leiden/Amsterdam Center for Drug Research, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands
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van de Lagemaat R, Timmers C, Kelder J, van Koppen C, Mosselman S, Hanssen R. Induction of ovulation by a potent, orally active, low molecular weight agonist (Org 43553) of the luteinizing hormone receptor. Hum Reprod 2008; 24:640-8. [DOI: 10.1093/humrep/den412] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Dolle RE, Bourdonnec BL, Goodman AJ, Morales GA, Thomas CJ, Zhang W. Comprehensive Survey of Chemical Libraries for Drug Discovery and Chemical Biology: 2007. ACTA ACUST UNITED AC 2008; 10:753-802. [PMID: 18991466 DOI: 10.1021/cc800119z] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Roland E. Dolle
- Adolor Corporation, 700 Pennsylvania Drive, Exton, Pennsylvania 19341, Semafore Pharmaceuticals Inc., 8496 Georgetown Road, Indianapolis, Indiana 46268, NIH Chemical Genomics Center, National Human Genome Research Institute, National Institutes of Health, 9800 Medical Center Drive, Rockville, Maryland 20850, and Department of Chemistry, University of Massachusetts, 100 Morrissey Boulevard, Boston, Massachusetts 02125
| | - Bertrand Le Bourdonnec
- Adolor Corporation, 700 Pennsylvania Drive, Exton, Pennsylvania 19341, Semafore Pharmaceuticals Inc., 8496 Georgetown Road, Indianapolis, Indiana 46268, NIH Chemical Genomics Center, National Human Genome Research Institute, National Institutes of Health, 9800 Medical Center Drive, Rockville, Maryland 20850, and Department of Chemistry, University of Massachusetts, 100 Morrissey Boulevard, Boston, Massachusetts 02125
| | - Allan J. Goodman
- Adolor Corporation, 700 Pennsylvania Drive, Exton, Pennsylvania 19341, Semafore Pharmaceuticals Inc., 8496 Georgetown Road, Indianapolis, Indiana 46268, NIH Chemical Genomics Center, National Human Genome Research Institute, National Institutes of Health, 9800 Medical Center Drive, Rockville, Maryland 20850, and Department of Chemistry, University of Massachusetts, 100 Morrissey Boulevard, Boston, Massachusetts 02125
| | - Guillermo A. Morales
- Adolor Corporation, 700 Pennsylvania Drive, Exton, Pennsylvania 19341, Semafore Pharmaceuticals Inc., 8496 Georgetown Road, Indianapolis, Indiana 46268, NIH Chemical Genomics Center, National Human Genome Research Institute, National Institutes of Health, 9800 Medical Center Drive, Rockville, Maryland 20850, and Department of Chemistry, University of Massachusetts, 100 Morrissey Boulevard, Boston, Massachusetts 02125
| | - Craig J. Thomas
- Adolor Corporation, 700 Pennsylvania Drive, Exton, Pennsylvania 19341, Semafore Pharmaceuticals Inc., 8496 Georgetown Road, Indianapolis, Indiana 46268, NIH Chemical Genomics Center, National Human Genome Research Institute, National Institutes of Health, 9800 Medical Center Drive, Rockville, Maryland 20850, and Department of Chemistry, University of Massachusetts, 100 Morrissey Boulevard, Boston, Massachusetts 02125
| | - Wei Zhang
- Adolor Corporation, 700 Pennsylvania Drive, Exton, Pennsylvania 19341, Semafore Pharmaceuticals Inc., 8496 Georgetown Road, Indianapolis, Indiana 46268, NIH Chemical Genomics Center, National Human Genome Research Institute, National Institutes of Health, 9800 Medical Center Drive, Rockville, Maryland 20850, and Department of Chemistry, University of Massachusetts, 100 Morrissey Boulevard, Boston, Massachusetts 02125
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Arey BJ. Allosteric modulators of glycoprotein hormone receptors: discovery and therapeutic potential. Endocrine 2008; 34:1-10. [PMID: 18956257 DOI: 10.1007/s12020-008-9098-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2008] [Revised: 06/02/2008] [Accepted: 06/26/2008] [Indexed: 01/27/2023]
Abstract
The glycoprotein hormones, luteinizing hormone, follicle-stimulating hormone and thyroid stimulating hormone, are important regulators of reproductive and metabolic processes. However, because of the nature of their ligand-receptor interactions that contain multiple contact sites, classical small molecule drug discovery strategies have not been successful. However, recent advances in screening and combinatorial chemistry strategies have identified chemical series that act allosterically as positive, negative or mixed modulators of the glycoprotein hormone receptors. This review will discuss the discovery and highlight the currently known series of allosteric modulators to this therapeutically important family of G-protein coupled receptors. Lastly, we will present potential mechanisms whereby the different series could modulate receptor function in the context of currently held theory and known structure of G protein-coupled receptors.
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Affiliation(s)
- Brian J Arey
- Department of Metabolic and Cardiovascular Drug Discovery, Research and Development, Bristol-Myers Squibb Co, 311 Pennington Rocky-Hill Rd, Mail Stop 21-1.08, Pennington, NJ 08534, USA.
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28
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van Koppen CJ, Zaman GJR, Timmers CM, Kelder J, Mosselman S, van de Lagemaat R, Smit MJ, Hanssen RGJM. A signaling-selective, nanomolar potent allosteric low molecular weight agonist for the human luteinizing hormone receptor. Naunyn Schmiedebergs Arch Pharmacol 2008; 378:503-14. [PMID: 18551279 DOI: 10.1007/s00210-008-0318-3] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2008] [Accepted: 05/21/2008] [Indexed: 10/22/2022]
Abstract
Luteinizing hormone (LH) and human chorionic gonadotropin (hCG) activate the LH receptor/cyclic AMP (cAMP) signaling pathway to induce ovulation. As an alternative to parenterally administered hCG to treat anovulatory infertility, orally active low molecular weight (LMW) LHR agonists have been developed at Organon. In this paper, we present the mechanism of action of a prototypic, nanomolar potent and almost full LHR agonist, Org 43553. Org 43553 interacts with the endodomain of the LHR, whereas LH acts via the N-terminal exodomain. LH stimulates the cAMP pathway with an EC50 of 35 pM, but this stimulation is not antagonized by simultaneous incubation with Org 43553. At nanomolar concentrations, LH also stimulates phospholipase C (PLC), but Org 43553 is hardly able to do so. In contrast, Org 43553 inhibits LH-induced PLC (IC50 approximately 10 nM). While Org 43553 stimulates dissociation of [125I]hCG from the LHR and reduces [125I]hCG binding, LH reduces specific [3H]Org 43553 binding. We conclude that Org 43553 is a signaling-selective, allosteric LHR agonist. We hypothesize that Org 43553 and LH induce a similar LHR conformation necessary for activating adenylyl cyclase, which initiates most, if not all, physiological responses of LH.
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Affiliation(s)
- Chris J van Koppen
- Department of Molecular Pharmacology, N.V. Organon, a part of Schering-Plough Corporation, 5340 BH, Oss, The Netherlands.
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Nikpour F, Beigvand M. A facile and convenient approach to the synthesis of 3,5-diaryl-1H-pyrazoles. MONATSHEFTE FUR CHEMIE 2008. [DOI: 10.1007/s00706-007-0829-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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