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Abstract
The oxytocin receptor plays a significant role in peripheral regulation of parturition and lactation. Given this important role, multiple drug discovery programs have been conducted to develop agonists and antagonists for peripheral activity. The role of the oxytocin receptor in the central nervous system is also significant, promoting social interaction, trust, and empathy in humans. As such, molecules that can access the central nervous system and target the oxytocin receptor are of significant interest. Due to the role of the oxytocin receptor in regulating social function and psychological well-being, agonists of this receptor have considerable promise for the treatment of numerous neuropsychiatric conditions. The poor pharmacokinetic properties and blood-brain barrier penetration of peptide-based molecules means nonpeptide compounds have more commonly been the focus for central nervous system activity. This chapter aims to summarize the current standing of peptide and nonpeptide drug discovery for antagonists and agonists of the oxytocin receptor and focusses on centrally active nonpeptidic agonists.
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Marchand G, Blumrick R, Ruuska AD, Ware K, Masoud AT, King A, Ruther S, Brazil G, Cieminski K, Calteux N, Ulibarri H, Sainz K. Novel oxytocin receptor antagonists for tocolysis: a systematic review and meta-analysis of the available data on the efficacy, safety, and tolerability of retosiban. Curr Med Res Opin 2021; 37:1677-1688. [PMID: 34134590 DOI: 10.1080/03007995.2021.1944076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
OBJECTIVE To assess the efficacy, safety, and tolerability of retosiban-a novel tocolytic unavailable in the US-in the management of preterm labor. METHODS We searched ClinicalTrials.Gov, MEDLINE, PubMed, SCOPUS, Web of Science, and the Cochrane Library for relevant clinical trials using the terms "retosiban" and "preterm labor" through 09/2020. We included all published randomized clinical trials (three) that compared retosiban to placebo for preterm labor, excluding conferences, books, reviews, posters, case reports, and animal studies. We analyzed homogeneous data under the fixed-effects model and heterogeneous data under the random-effects model. RESULTS We included all randomized clinical trials addressing this topic, which ultimately resulted in three trials with a total of 116 patients. There were no significant differences between retosiban and placebo in births at term (RR = 0.41, p = .02), births ≤7 days from the first study treatment (RR = 0.59, p = .23), or administration of rescue tocolytic (RR = 0.36, p = .07); the maternal adverse events of headache, anemia, constipation, or urinary tract infection (p > .05); or neonatal outcomes of Apgar score at 1 min (p = .88) or 5 min (p = .69), weight (p = .23), head circumference (p = .55), malnutrition (p = .27), hyperbilirubinemia (RR = 0.56, p = .21), jaundice (RR = 1.21, p = .84), respiratory distress (RR = 0.53, p = .49), or tachypnea (RR = 0.40, p = .42). CONCLUSION With the limited high quality evidence available, retosiban demonstrates no clear benefit over placebo in the management of preterm labor. Nevertheless, its favorable safety profile, oral bioavailability, and novel mechanism of action and the limited number of studies available for review warrant further analysis.
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Affiliation(s)
- Greg Marchand
- Marchand Institute for Minimally Invasive Surgery, Mesa, AZ, USA
| | | | - Alexandra D Ruuska
- Marchand Institute for Minimally Invasive Surgery, Mesa, AZ, USA
- Midwestern University Arizona College of Osteopathic Medicine, Glendale, AZ, USA
| | - Kelly Ware
- Marchand Institute for Minimally Invasive Surgery, Mesa, AZ, USA
- International University of Health Sciences, Basseterre, St. Kitts
| | - Ahmed Taher Masoud
- Marchand Institute for Minimally Invasive Surgery, Mesa, AZ, USA
- Fayoum University Faculty of Medicine, Fayoum, Egypt
| | - Alexa King
- Marchand Institute for Minimally Invasive Surgery, Mesa, AZ, USA
| | - Stacy Ruther
- Marchand Institute for Minimally Invasive Surgery, Mesa, AZ, USA
| | - Giovanna Brazil
- Marchand Institute for Minimally Invasive Surgery, Mesa, AZ, USA
| | | | - Nicolas Calteux
- Marchand Institute for Minimally Invasive Surgery, Mesa, AZ, USA
| | - Hollie Ulibarri
- Marchand Institute for Minimally Invasive Surgery, Mesa, AZ, USA
| | - Katelyn Sainz
- Marchand Institute for Minimally Invasive Surgery, Mesa, AZ, USA
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Malik M, Roh M, England SK. Uterine contractions in rodent models and humans. Acta Physiol (Oxf) 2021; 231:e13607. [PMID: 33337577 PMCID: PMC8047897 DOI: 10.1111/apha.13607] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 12/07/2020] [Accepted: 12/11/2020] [Indexed: 12/18/2022]
Abstract
Aberrant uterine contractions can lead to preterm birth and other labour complications and are a significant cause of maternal morbidity and mortality. To investigate the mechanisms underlying dysfunctional uterine contractions, researchers have used experimentally tractable small animal models. However, biological differences between humans and rodents change how researchers select their animal model and interpret their results. Here, we provide a general review of studies of uterine excitation and contractions in mice, rats, guinea pigs, and humans, in an effort to introduce new researchers to the field and help in the design and interpretation of experiments in rodent models.
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Affiliation(s)
- Manasi Malik
- Center for Reproductive Health SciencesDepartment of Obstetrics and GynecologyWashington University School of MedicineSt. LouisMOUSA
| | - Michelle Roh
- Center for Reproductive Health SciencesDepartment of Obstetrics and GynecologyWashington University School of MedicineSt. LouisMOUSA
| | - Sarah K. England
- Center for Reproductive Health SciencesDepartment of Obstetrics and GynecologyWashington University School of MedicineSt. LouisMOUSA
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4
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Stadler B, Whittaker MR, Exintaris B, Middendorff R. Oxytocin in the Male Reproductive Tract; The Therapeutic Potential of Oxytocin-Agonists and-Antagonists. Front Endocrinol (Lausanne) 2020; 11:565731. [PMID: 33193084 PMCID: PMC7642622 DOI: 10.3389/fendo.2020.565731] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 09/07/2020] [Indexed: 12/12/2022] Open
Abstract
In this review, the role of oxytocin and oxytocin-like agents (acting via the oxytocin receptor and belonging to the oxytocin-family) in the male reproductive tract is considered. Previous research (dating back over 60 years) is revised and connected with recently found aspects of the role oxytocin plays in male reproductive health. The local expression of oxytocin and its receptor in the male reproductive tract of different species is summarized. Colocalization and possible crosstalk to other agents and receptors and their resulting effects are discussed. The role of the newly reported oxytocin focused signaling pathways in the male reproductive tract, other than mediating contractility, is critically examined. The structure and effect of the most promising oxytocin-agonists and -antagonists are reviewed for their potential in treating male disorders with origins in the male reproductive tract such as prostate diseases and ejaculatory disorders.
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Affiliation(s)
- Beatrix Stadler
- Institute of Anatomy and Cell Biology, Justus-Liebig-University, Giessen, Germany
| | - Michael R. Whittaker
- Drug Discovery Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Melbourne, VIC, Australia
| | - Betty Exintaris
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Melbourne, VIC, Australia
| | - Ralf Middendorff
- Institute of Anatomy and Cell Biology, Justus-Liebig-University, Giessen, Germany
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5
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Brighton PJ, Fossler MJ, Quenby S, Blanks AM. Functionally Selective Inhibition of the Oxytocin Receptor by Retosiban in Human Myometrial Smooth Muscle. Endocrinology 2020; 161:5697361. [PMID: 31907536 DOI: 10.1210/endocr/bqz043] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 01/06/2020] [Indexed: 11/19/2022]
Abstract
Novel small molecule inhibitors of the oxytocin receptor (OTR) may have distinct pharmacology and mode of action when compared with first-generation oxytocin antagonists when used for the prevention of preterm birth. The aim was to determine the mechanism of action of small molecule OTR antagonists retosiban and epelsiban compared with the currently used peptide-based compound atosiban. Human myometrial samples were obtained at cesarean section and subjected to pharmacological manipulations to establish the effect of antagonist binding to OTR on downstream signaling. Retosiban antagonism of oxytocin action in human myometrium was potent, rapid, and reversible. Inhibition of inositol 1,4,5-trisphosphate (IP3) production followed single-site competitive binding kinetics for epelsiban, retosiban, and atosiban. Retosiban inhibited basal production of IP3 in the absence of oxytocin. Oxytocin and atosiban but not retosiban inhibited forskolin, and calcitonin stimulated 3',5'-cyclic adenosine 5'-mono-phosphate (cAMP) production. Inhibition of cAMP was reversed by pertussis toxin. Oxytocin and atosiban, but not retosiban and epelsiban, stimulated extracellular regulated kinase (ERK)1/2 activity in a time- and concentration-dependent manner. Oxytocin and atosiban stimulated cyclo-oxygenase 2 activity and subsequent production of prostaglandin E2 and F2α. Prostaglandin production was inhibited by rofecoxib, pertussin toxin, and ERK inhibitor U0126. Oxytocin but not retosiban or atosiban stimulated coupling of the OTR to Gα q G-proteins. Oxytocin and atosiban but not retosiban stimulated coupling of the OTR to Gα i G-proteins. Retosiban and epelsiban demonstrate distinct pharmacology when compared with atosiban in human myometrial smooth muscle. Atosiban displays agonist activity at micromolar concentrations leading to stimulation of prostaglandin production.
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Affiliation(s)
- Paul J Brighton
- Cell and Developmental Biology, Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Warwick CV2 2DX, UK
| | - Michael J Fossler
- Clinical Pharmacology Modeling and Simulation, GlaxoSmithKline, Upper Merion West, King of Prussia, Pennsylvania
| | - Siobhan Quenby
- Cell and Developmental Biology, Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Warwick CV2 2DX, UK
- Maternity Directorate, University Hospital Coventry and Warwickshire, Coventry CV2 2DX, UK
| | - Andrew M Blanks
- Cell and Developmental Biology, Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Warwick CV2 2DX, UK
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Roy RK, Augustine RA, Brown CH, Schwenke DO. Activation of oxytocin neurons in the paraventricular nucleus drives cardiac sympathetic nerve activation following myocardial infarction in rats. Commun Biol 2018; 1:160. [PMID: 30320228 PMCID: PMC6172223 DOI: 10.1038/s42003-018-0169-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Accepted: 09/10/2018] [Indexed: 01/16/2023] Open
Abstract
Myocardial infarction (MI) initiates an increase in cardiac sympathetic nerve activity (SNA) that facilitates potentially fatal arrhythmias. The mechanism(s) underpinning sympathetic activation remain unclear. Some neuronal populations within the hypothalamic paraventricular nucleus (PVN) have been implicated in SNA. This study elucidated the role of the PVN in triggering cardiac SNA following MI (left anterior descending coronary artery ligation). By means of c-Fos, oxytocin, and vasopressin immunohistochemistry accompanied by retrograde tracing we showed that MI activates parvocellular oxytocin neurons projecting to the rostral ventral lateral medulla. Central inhibition of oxytocin receptors using atosiban (4.5 µg in 5 µl, i.c.v.), or retosiban (3 mg/kg, i.v.), prevented the MI-induced increase in SNA and reduced the incidence of ventricular arrhythmias and mortality. In conclusion, pre-autonomic oxytocin neurons can drive the increase in cardiac SNA following MI and peripheral administration of an oxytocin receptor blocker could be a plausible therapeutic strategy to improve outcomes for MI patients. Roy et al. showed that activation of parvocellular pre-autonomic oxytocin neurons increased sympathetic nerve activity following myocardial infarction. This and other aberrant physiological changes induced by acute myocardial infarction were decreased by oxytocin receptor antagonists, hinting to their potential therapeutic role.
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Affiliation(s)
- Ranjan K Roy
- Department of Physiology-HeartOtago, University of Otago, Dunedin, 9054, New Zealand
| | - Rachael A Augustine
- Department of Physiology-HeartOtago, University of Otago, Dunedin, 9054, New Zealand.,Brain Health Research Centre, University of Otago, Dunedin, 9054, New Zealand.,Centre for Neuroendocrinology, University of Otago, Dunedin, 9054, New Zealand
| | - Colin H Brown
- Department of Physiology-HeartOtago, University of Otago, Dunedin, 9054, New Zealand.,Brain Health Research Centre, University of Otago, Dunedin, 9054, New Zealand.,Centre for Neuroendocrinology, University of Otago, Dunedin, 9054, New Zealand
| | - Daryl O Schwenke
- Department of Physiology-HeartOtago, University of Otago, Dunedin, 9054, New Zealand.
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Aye ILMH, Moraitis AA, Stanislaus D, Charnock-Jones DS, Smith GCS. Retosiban Prevents Stretch-Induced Human Myometrial Contractility and Delays Labor in Cynomolgus Monkeys. J Clin Endocrinol Metab 2018; 103:1056-1067. [PMID: 29293998 PMCID: PMC5868409 DOI: 10.1210/jc.2017-02195] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 12/20/2017] [Indexed: 12/13/2022]
Abstract
Context Stretch of the myometrium promotes its contractility and is believed to contribute to the control of parturition at term and to the increased risk of preterm birth in multiple pregnancies. Objective To determine the effects of the putative oxytocin receptor (OTR) inverse agonist retosiban on (1) the contractility of human myometrial explants and (2) labor in nonhuman primates. Design Human myometrial biopsies were obtained at planned term cesarean, and explants were exposed to stretch in the presence and absence of a range of drugs, including retosiban. The in vivo effects of retosiban were determined in cynomolgus monkeys. Results Prolonged mechanical stretch promoted myometrial extracellular signal-regulated kinase (ERK)1/2 phosphorylation. Moreover, stretch-induced stimulation of myometrial contractility was prevented by ERK1/2 inhibitors. Retosiban (10 nM) prevented stretch-induced stimulation of myometrial contractility and phosphorylation of ERK1/2. Moreover, the inhibitory effect of retosiban on stretch-induced ERK1/2 phosphorylation was prevented by coincubation with a 100-fold excess of a peptide OTR antagonist, atosiban. Compared with vehicle-treated cynomolgus monkeys, treatment with oral retosiban (100 to 150 days of gestational age) reduced the risk of spontaneous delivery (hazard ratio = 0.07, 95% confidence interval 0.01 to 0.60, P = 0.015). Conclusions The OTR acts as a uterine mechanosensor, whereby stretch increases myometrial contractility through agonist-free activation of the OTR. Retosiban prevents this through inverse agonism of the OTR and, in vivo, reduced the likelihood of spontaneous labor in nonhuman primates. We hypothesize that retosiban may be an effective preventative treatment of preterm birth in high-risk multiple pregnancies, an area of unmet clinical need.
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Affiliation(s)
- Irving L M H Aye
- Department of Obstetrics and Gynaecology, University of Cambridge, National Institute for Health Research, Cambridge Comprehensive Biomedical Research Centre, Cambridge, United Kingdom
| | - Alexandros A Moraitis
- Department of Obstetrics and Gynaecology, University of Cambridge, National Institute for Health Research, Cambridge Comprehensive Biomedical Research Centre, Cambridge, United Kingdom
| | - Dinesh Stanislaus
- Department of Reproductive Toxicology, GlaxoSmithKline, Philadelphia Navy Yard, Philadelphia, Pennsylvania
| | - D Stephen Charnock-Jones
- Department of Obstetrics and Gynaecology, University of Cambridge, National Institute for Health Research, Cambridge Comprehensive Biomedical Research Centre, Cambridge, United Kingdom
| | - Gordon C S Smith
- Department of Obstetrics and Gynaecology, University of Cambridge, National Institute for Health Research, Cambridge Comprehensive Biomedical Research Centre, Cambridge, United Kingdom
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8
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Thornton S, Valenzuela G, Baidoo C, Fossler MJ, Montague TH, Clayton L, Powell M, Snidow J, Stier B, Soergel D. Treatment of spontaneous preterm labour with retosiban: a phase II pilot dose-ranging study. Br J Clin Pharmacol 2017; 83:2283-2291. [PMID: 28556962 PMCID: PMC5595955 DOI: 10.1111/bcp.13336] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 05/12/2017] [Accepted: 05/17/2017] [Indexed: 11/27/2022] Open
Abstract
Aims The aims of the present study were to investigate the maternal, fetal and neonatal safety and tolerability, pharmacodynamics and pharmacokinetics of intravenous (IV) retosiban in pregnant women with spontaneous preterm labour (PTL) between 340/7 and 356/7 weeks' gestation. Methods In parts A and B of a three‐part, double‐blind, placebo‐controlled, multicentre study, women were randomized 3:1 (Part A) or 2:1 (Part B) to either 12‐h IV retosiban followed by a single dose of oral placebo (R‐P) or 12‐h IV placebo followed by single‐dose oral retosiban (P‐R). Results A total of 29 women were randomized; 20 to R‐P and nine to P‐R. An integrated analysis found that adverse events were infrequent in mothers/newborns and consistent with events expected in the population under study or associated with confounding factors. Retosiban was rapidly absorbed after oral administration, with an observed half‐life of 1.45 h. Efficacy analyses included 19 women. While not statistically significant, those receiving R‐P more frequently achieved uterine quiescence in 6 h (R‐P, 63%; 95% credible interval [CrI]: 38, 84; P‐R, 43%; 95% CrI: 12, 78) and more achieved a reduction of ≥50% in uterine contractions in 6 h (R‐P, 63%; 95% CrI: 38, 84; P‐R, 29%; 95% CrI: 4, 64). The number of days to delivery was increased in women receiving R‐P (median 26 days for R‐P vs. 13 days for P‐R). Conclusions Intravenous retosiban has a favourable safety and tolerability profile and might prolong pregnancies in women with PTL. The study provides the rationale and dosing strategy for further evaluation of the efficacy of retosiban in the treatment of PTL.
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Affiliation(s)
- Steven Thornton
- Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | | | | | - Michael J Fossler
- Quantitative Sciences, GSK, Uxbridge, UK.,Quantitative Sciences, GSK, King of Prussia, PA, USA
| | - Timothy H Montague
- Quantitative Sciences, GSK, Uxbridge, UK.,Quantitative Sciences, GSK, King of Prussia, PA, USA
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Thornton S, Miller H, Valenzuela G, Snidow J, Stier B, Fossler MJ, Montague TH, Powell M, Beach KJ. Treatment of spontaneous preterm labour with retosiban: a phase 2 proof-of-concept study. Br J Clin Pharmacol 2015; 80:740-9. [PMID: 25819462 DOI: 10.1111/bcp.12646] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Revised: 03/19/2015] [Accepted: 03/22/2015] [Indexed: 11/29/2022] Open
Abstract
AIM The aim was to investigate the efficacy and safety of intravenous retosiban in women with spontaneous preterm labour. METHODS This was a randomized, double-blind, placebo-controlled, phase 2 trial. Retosiban was administered intravenously for 48 h to women in spontaneous preterm labour between 30(0/7) and 35(6/7) weeks' gestation with an uncomplicated singleton pregnancy in an in-patient obstetric unit. Outcome measures were uterine quiescence (primary endpoint), days to delivery, preterm delivery and safety. RESULTS Uterine quiescence was achieved in 62% of women who received retosiban (n = 30) compared with 41% who received placebo (n = 34). The relative risk (RR) was 1.53 (95% credible interval [CrI] 0.98, 2.48; NS). Retosiban resulted in a significant increase in time to delivery compared with placebo (mean difference 8.2 days, 95% CrI 2.7, 13.74). This difference was consistent across all gestational ages. The proportion of preterm births in the retosiban and placebo groups was 18.7% (95% CrI 7.4%, 33.7%) and 47.2% (95% CrI 31.4%, 63.4%), respectively. The RR of preterm birth in women treated with retosiban was 0.38 (95% CrI 0.15, 0.81). There were no deliveries within 7 days in the retosiban group, but there were six (17.6%) births in the placebo group. The maternal, fetal and neonatal adverse events were comparable in the retosiban and placebo groups. CONCLUSIONS Intravenous administration of retosiban in women with spontaneous preterm labour was associated with a greater than 1 week increase in time to delivery compared with placebo, a significant reduction in preterm deliveries, a non-significant increase in uterine quiescence and a favourable safety profile.
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Affiliation(s)
| | - Hugh Miller
- Watching Over Mothers and Babies Foundation, Tucson, AZ, USA
| | | | - Jerry Snidow
- GlaxoSmithKline, Research Triangle Park, NC, USA
| | | | | | | | - Marcy Powell
- GlaxoSmithKline, Research Triangle Park, NC, USA
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Arrowsmith S, Wray S. Oxytocin: its mechanism of action and receptor signalling in the myometrium. J Neuroendocrinol 2014; 26:356-69. [PMID: 24888645 DOI: 10.1111/jne.12154] [Citation(s) in RCA: 161] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 03/14/2014] [Accepted: 03/28/2014] [Indexed: 12/17/2022]
Abstract
Oxytocin is a nonapeptide hormone that has a central role in the regulation of parturition and lactation. In this review, we address oxytocin receptor (OTR) signalling and its role in the myometrium during pregnancy and in labour. The OTR belongs to the rhodopsin-type (Class 1) of the G-protein coupled receptor superfamily and is regulated by changes in receptor expression, receptor desensitisation and local changes in oxytocin concentration. Receptor activation triggers a number of signalling events to stimulate contraction, primarily by elevating intracellular calcium (Ca(2+) ). This includes inositol-tris-phosphate-mediated store calcium release, store-operated Ca(2+) entry and voltage-operated Ca(2+) entry. We discuss each mechanism in turn and also discuss Ca(2+) -independent mechanisms such as Ca(2+) sensitisation. Because oxytocin induces contraction in the myometrium, both the activation and the inhibition of its receptor have long been targets in the management of dysfunctional and preterm labours, respectively. We discuss current and novel OTR agonists and antagonists and their use and potential benefit in obstetric practice. In this regard, we highlight three clinical scenarios: dysfunctional labour, postpartum haemorrhage and preterm birth.
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Affiliation(s)
- S Arrowsmith
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool, UK
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11
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Affiliation(s)
- Alexander Dömling
- Department of Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, USA.
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12
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Vrachnis N, Malamas FM, Sifakis S, Deligeoroglou E, Iliodromiti Z. The oxytocin-oxytocin receptor system and its antagonists as tocolytic agents. Int J Endocrinol 2011; 2011:350546. [PMID: 22190926 PMCID: PMC3235456 DOI: 10.1155/2011/350546] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2011] [Accepted: 09/25/2011] [Indexed: 12/29/2022] Open
Abstract
Oxytocin, a hormone involved in numerous physiologic processes, plays a central role in the mechanisms of parturition and lactation. It acts through its receptor, which belongs to the G-protein-coupled receptor superfamily, while Gq/phospholipase C (PLC)/inositol 1,4,5-triphosphate (InsP3) is the main pathway via which it exerts its action in the myometrium. Changes in receptor levels, receptor desensitization, and locally produced oxytocin are factors that influence the effect of oxytocin on uterine contractility in labor. Activation of oxytocin receptor causes myometrial contractions by increasing intracellular Ca(+2) and production of prostaglandins. Since oxytocin induces contractions, the inhibition of its action has been a target in the management of preterm labor. Atosiban is today the only oxytocin receptor antagonist that is available as a tocolytic. However, the quest for oxytocin receptor antagonists with a better pharmacological profile has led to the synthesis of peptide and nonpeptide molecules such as barusiban, retosiban, L-368,899, and SSR-126768A. Many of these oxytocin receptor antagonists are used only as pharmacological tools, while others have tocolytic action. In this paper, we summarize the action of oxytocin and its receptor and we present an overview of the clinical and experimental data of oxytocin antagonists and their tocolytic action.
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Affiliation(s)
- Nikolaos Vrachnis
- 2nd Department of Obstetrics and Gynecology, Aretaieio Hospital, University of Athens Medical School, 11526 Athens, Greece
- *Nikolaos Vrachnis:
| | - Fotodotis M. Malamas
- 1st Department of Obstetrics and Gynecology, Alexandra Hospital, University of Athens Medical School, 11526 Athens, Greece
| | - Stavros Sifakis
- Department of Obstetrics and Gynaecology, University Hospital of Heraklion, 71110 Heraklion, Crete, Greece
| | - Efthymios Deligeoroglou
- 2nd Department of Obstetrics and Gynecology, Aretaieio Hospital, University of Athens Medical School, 11526 Athens, Greece
| | - Zoe Iliodromiti
- 2nd Department of Obstetrics and Gynecology, Aretaieio Hospital, University of Athens Medical School, 11526 Athens, Greece
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Viero C, Shibuya I, Kitamura N, Verkhratsky A, Fujihara H, Katoh A, Ueta Y, Zingg HH, Chvatal A, Sykova E, Dayanithi G. REVIEW: Oxytocin: Crossing the bridge between basic science and pharmacotherapy. CNS Neurosci Ther 2010; 16:e138-56. [PMID: 20626426 PMCID: PMC2972642 DOI: 10.1111/j.1755-5949.2010.00185.x] [Citation(s) in RCA: 167] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Is oxytocin the hormone of happiness? Probably not. However, this small nine amino acid peptide is involved in a wide variety of physiological and pathological functions such as sexual activity, penile erection, ejaculation, pregnancy, uterus contraction, milk ejection, maternal behavior, osteoporosis, diabetes, cancer, social bonding, and stress, which makes oxytocin and its receptor potential candidates as targets for drug therapy. In this review, we address the issues of drug design and specificity and focus our discussion on recent findings on oxytocin and its heterotrimeric G protein‐coupled receptor OTR. In this regard, we will highlight the following topics: (i) the role of oxytocin in behavior and affectivity, (ii) the relationship between oxytocin and stress with emphasis on the hypothalamo–pituitary–adrenal axis, (iii) the involvement of oxytocin in pain regulation and nociception, (iv) the specific action mechanisms of oxytocin on intracellular Ca2+ in the hypothalamo neurohypophysial system (HNS) cell bodies, (v) newly generated transgenic rats tagged by a visible fluorescent protein to study the physiology of vasopressin and oxytocin, and (vi) the action of the neurohypophysial hormone outside the central nervous system, including the myometrium, heart and peripheral nervous system. As a short nine amino acid peptide, closely related to its partner peptide vasopressin, oxytocin appears to be ideal for the design of agonists and antagonists of its receptor. In addition, not only the hormone itself and its binding to OTR, but also its synthesis, storage and release can be endogenously and exogenously regulated to counteract pathophysiological states. Understanding the fundamental physiopharmacology of the effects of oxytocin is an important and necessary approach for developing a potential pharmacotherapy.
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Affiliation(s)
- Cedric Viero
- Department of Cardiology, Wales Heart Research Institute, Cardiff University, UK
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Lee HJ, Macbeth AH, Pagani JH, Young WS. Oxytocin: the great facilitator of life. Prog Neurobiol 2009; 88:127-51. [PMID: 19482229 DOI: 10.1016/j.pneurobio.2009.04.001] [Citation(s) in RCA: 339] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2008] [Revised: 02/24/2009] [Accepted: 04/02/2009] [Indexed: 01/01/2023]
Abstract
Oxytocin (Oxt) is a nonapeptide hormone best known for its role in lactation and parturition. Since 1906 when its uterine-contracting properties were described until 50 years later when its sequence was elucidated, research has focused on its peripheral roles in reproduction. Only over the past several decades have researchers focused on what functions Oxt might have in the brain, the subject of this review. Immunohistochemical studies revealed that magnocellular neurons of the hypothalamic paraventricular and supraoptic nuclei are the neurons of origin for the Oxt released from the posterior pituitary. Smaller cells in various parts of the brain, as well as release from magnocellular dendrites, provide the Oxt responsible for modulating various behaviors at its only identified receptor. Although Oxt is implicated in a variety of "non-social" behaviors, such as learning, anxiety, feeding and pain perception, it is Oxt's roles in various social behaviors that have come to the fore recently. Oxt is important for social memory and attachment, sexual and maternal behavior, and aggression. Recent work implicates Oxt in human bonding and trust as well. Human disorders characterized by aberrant social interactions, such as autism and schizophrenia, may also involve Oxt expression. Many, if not most, of Oxt's functions, from social interactions (affiliation, aggression) and sexual behavior to eventual parturition, lactation and maternal behavior, may be viewed as specifically facilitating species propagation.
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Affiliation(s)
- Heon-Jin Lee
- Section on Neural Gene Expression, NIMH, NIH, DHHS, Bethesda, MD 20892, USA
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O'Neill J, Blackwell HE. Solid-phase and microwave-assisted syntheses of 2,5-diketopiperazines: small molecules with great potential. Comb Chem High Throughput Screen 2007; 10:857-76. [PMID: 18288948 PMCID: PMC2585775 DOI: 10.2174/138620707783220365] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Diketopiperazines (DKPs) are a well-known class of heterocycles that have recently emerged as a promising biologically active scaffold. Solid-phase organic synthesis has become an important tool in the combinatorial exploration of these privileged structures, expediting the synthesis and, therefore, the discovery of active compounds. To date, certain DKPs have shown potent activities against a range of diseases and biological phenomena, including bacterial infections, various cancers, asthma, infertility, premature labor, and HIV. Recent applications of solid-phase DKP synthesis, with a particular focus on cyclative cleavage and microwave-assisted reactions, are highlighted herein.
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Affiliation(s)
- J.C. O'Neill
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Avenue, Madison, Wisconsin 53706, USA
| | - H. E. Blackwell
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Avenue, Madison, Wisconsin 53706, USA
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