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Chamberlain F, Grammatopoulos D. Methodology for Isolation of miRNA From the Serum of Women Investigated for Pre-eclampsia. Cureus 2023; 15:e46181. [PMID: 37905272 PMCID: PMC10613333 DOI: 10.7759/cureus.46181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/29/2023] [Indexed: 11/02/2023] Open
Abstract
Background Pre-eclampsia remains a leading cause of maternal and foetal mortality with a poorly understood pathophysiology. It can lead to a range of clinical presentations, but proteinuria and hypertension are key components of the diagnosis. These signs arise due to disordered placental implantation due to poor trophoblastic invasion, resulting in placental oxidative stress due to hypoxia. Oxidative stress triggers the release of syncytiotrophoblast microvesicles (STMBs), of which placenta-derived exosomes may be a key component. The high specificity of exosomes for their cell of origin makes them ideal candidates as diagnostic biomarkers. We are particularly interested in the miRNAs (microRNAs) contained within these exosomes, as they may give us an insight into the genomic regulation within the pre-eclamptic placenta that leads to the disease state. The development of workflows for miRNA quantitation may enable us to identify novel biomarkers. Methods We extracted exosomes and purified total RNA from 23 serum samples using the Norgen Plasma/Serum Exosome Purification and RNA Isolation Midi Kit. We then used the bioanalyser to determine the concentration and quality of the RNA obtained. It uses rapid electrophoresis, requires minimal sample sizes, and can assess the quality of genetic material as small as 25 bases. Results We have successfully isolated RNA from these samples; however, the concentration of the total RNA was too low for downstream molecular analysis. We did gain insight into how to optimise and develop the workflow so that, with each attempt, the yield increased. Our greatest concentrations were obtained by combining serum samples from multiple patients, demonstrating that we needed a higher volume to optimise the yield. Future studies should aim to obtain samples specifically for use in this research so that we can process a larger volume of serum. Conclusions We have also noted that there is a positive correlation between the overall concentration of total RNA and a high sFlt-1/PlGF ratio. Preliminary analysis from Illumina identified with a high degree of confidence the presence of three miRNAs, namely, mir-498(46), mir-122(1), and mir-134(41). Further work is necessary to validate these findings and should focus on the possible future role of these miRNAs as biomarkers for the early diagnosis of pre-eclampsia.
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Chávez J, Alcántara-Alonso V, García-Luna C, Soberanes-Chávez P, Grammatopoulos D, de Gortari P. Hypothalamic TRH mediates anorectic effects of serotonin in rats. eNeuro 2022; 9:ENEURO.0077-22.2022. [PMID: 35545425 PMCID: PMC9159524 DOI: 10.1523/eneuro.0077-22.2022] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 04/26/2022] [Accepted: 04/28/2022] [Indexed: 11/21/2022] Open
Abstract
Among the modulatory functions of thyrotropin-releasing hormone (TRH), an anorectic behavior in rodents is observed when centrally injected. Hypothalamic PVN neurons receive serotonergic inputs from dorsal raphe nucleus and express serotonin (5HT) receptors such as 5HT1A, 5HT2A/2C, 5HT6, which are involved in 5HT-induced feeding regulation. Rats subjected to dehydration-induced anorexia (DIA) model show increased PVN TRH mRNA expression, associated with their decreased food intake. We analyzed whether 5HT input is implicated in the enhanced PVN TRH transcription that anorectic rats exhibit, given that 5HT increases TRH expression and release when studied in vitro By using mHypoA-2/30 hypothalamic cell cultures, we found that 5HT stimulated TRH mRNA, pCREB and pERK1/2 levels. By inhibiting basal PKA or PKC activities or those induced by 5HT, pCREB or pERK1/2 content did not increase suggesting involvement of both kinases in their phosphorylation. 5HT effect on TRH mRNA was not affected by PKA inhibition, but it diminished in the presence of PKCi suggesting involvement of PKC in 5HT-induced TRH increased transcription. This likely involves 5HT2A/2C and the activation of alternative transduction pathways than those studied here. In agreement with the in vitro data, we found that injecting 5HT2A/2C antagonists into the PVN of DIA rats reversed the increased TRH expression of anorectic animals, as well as their decreased food intake; also, the agonist reduced food intake of hungry restricted animals along with elevated PVN TRH mRNA levels. Our results support that the anorectic effects of serotonin are mediated by PVN TRH in this model.Significance statementInteraction between brain peptides and neurotransmitters' pathways regulates feeding behavior, but when altered it could lead to the development of eating disorders, such as anorexia. An abnormal increased TRH expression in hypothalamic PVN results in dehydration-induced anorectic rats, associated to their low food intake. The role of neurotransmitters in that alteration is unknown, and since serotonin inhibits feeding and has receptors in PVN, we analyzed its participation in increasing TRH expression and reducing feeding in anorectic rats. By antagonizing PVN serotonin receptors in anorectic rats, we identify decreased TRH expression and increased feeding, suggesting that the anorectic effects of serotonin are mediated by PVN TRH. Elucidating brain networks involved in feeding regulation would help to design therapies for eating disorders.
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Affiliation(s)
- Jorge Chávez
- Molecular Neurophysiology laboratory, Department of Neuroscience, National Institute of Psychiatry "Ramón de la Fuente Muñiz", Mexico City, Mexico 14370
| | - Viridiana Alcántara-Alonso
- Molecular Neurophysiology laboratory, Department of Neuroscience, National Institute of Psychiatry "Ramón de la Fuente Muñiz", Mexico City, Mexico 14370
- Translational Medicine, Warwick Medical School, Coventry, United Kingdom CV4 7HL
| | - Cinthia García-Luna
- Molecular Neurophysiology laboratory, Department of Neuroscience, National Institute of Psychiatry "Ramón de la Fuente Muñiz", Mexico City, Mexico 14370
| | - Paulina Soberanes-Chávez
- Molecular Neurophysiology laboratory, Department of Neuroscience, National Institute of Psychiatry "Ramón de la Fuente Muñiz", Mexico City, Mexico 14370
| | - Dimitris Grammatopoulos
- Translational Medicine, Warwick Medical School, Coventry, United Kingdom CV4 7HL
- Institute of Precision Diagnostics and Translational Medicine, Division of Pathology, UHCW NHS Trust, Coventry, United Kingdom CV2 2DX
| | - Patricia de Gortari
- Molecular Neurophysiology laboratory, Department of Neuroscience, National Institute of Psychiatry "Ramón de la Fuente Muñiz", Mexico City, Mexico 14370.
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Armitage C, Braybrook E, Anderson N, Grammatopoulos D. T167 Measurement of plasma allopregnanolone levels and the impact of solid phase extraction step on competitive immunoassay performance. Clin Chim Acta 2022. [DOI: 10.1016/j.cca.2022.04.646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Georgiou PG, Guy CS, Hasan M, Ahmad A, Richards SJ, Baker AN, Thakkar NV, Walker M, Pandey S, Anderson NR, Grammatopoulos D, Gibson MI. Plasmonic Detection of SARS-CoV-2 Spike Protein with Polymer-Stabilized Glycosylated Gold Nanorods. ACS Macro Lett 2022; 11:317-322. [PMID: 35575357 PMCID: PMC8928465 DOI: 10.1021/acsmacrolett.1c00716] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
![]()
The COVID-19 pandemic
has highlighted the need for innovative biosensing,
diagnostic, and surveillance platforms. Here we report that glycosylated,
polymer-stabilized, gold nanorods can bind the SARS-CoV-2 spike protein
and show correlation to the presence of SARS-CoV-2 in primary COVID-19
clinical samples. Telechelic polymers were prepared by reversible
addition–fragmentation chain-transfer polymerization, enabling
the capture of 2,3-sialyllactose and immobilization onto gold nanorods.
Control experiments with a panel of lectins and a galactosamine-terminated
polymer confirmed the selective binding. The glycosylated rods were
shown to give dose-dependent responses against recombinant truncated
SARS-CoV-2 spike protein, and the responses were further correlated
using primary patient swab samples. The essentiality of the anisotropic
particles for reducing the background interference is demonstrated.
This highlights the utility of polymer tethering of glycans for plasmonic
biosensors of infection.
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Affiliation(s)
| | - Collette S. Guy
- Department of Chemistry, University of Warwick, Gibbet Hill Road, CV4 7AL Coventry, U.K
- School of Life Sciences, University of Warwick, CV4 7AL Coventry, U.K
| | - Muhammad Hasan
- Department of Chemistry, University of Warwick, Gibbet Hill Road, CV4 7AL Coventry, U.K
| | - Ashfaq Ahmad
- Department of Chemistry, University of Warwick, Gibbet Hill Road, CV4 7AL Coventry, U.K
| | - Sarah-Jane Richards
- Department of Chemistry, University of Warwick, Gibbet Hill Road, CV4 7AL Coventry, U.K
| | - Alexander N. Baker
- Department of Chemistry, University of Warwick, Gibbet Hill Road, CV4 7AL Coventry, U.K
| | - Neer V. Thakkar
- Department of Chemistry, University of Warwick, Gibbet Hill Road, CV4 7AL Coventry, U.K
| | - Marc Walker
- Department of Physics, University of Warwick, Gibbet Hill Road, CV4 7AL Coventry, U.K
| | - Sarojini Pandey
- Institute of Precision Diagnostics and Translational Medicine, University Hospitals Coventry and Warwickshire NHS Trust, Clifford Bridge Road Walsgrave, Coventry CV2 2DX, U.K
| | - Neil R. Anderson
- Institute of Precision Diagnostics and Translational Medicine, University Hospitals Coventry and Warwickshire NHS Trust, Clifford Bridge Road Walsgrave, Coventry CV2 2DX, U.K
| | - Dimitris Grammatopoulos
- Warwick Medical School, University of Warwick, Gibbet Hill Road, CV4 7AL Coventry, U.K
- Institute of Precision Diagnostics and Translational Medicine, University Hospitals Coventry and Warwickshire NHS Trust, Clifford Bridge Road Walsgrave, Coventry CV2 2DX, U.K
| | - Matthew I. Gibson
- Department of Chemistry, University of Warwick, Gibbet Hill Road, CV4 7AL Coventry, U.K
- Warwick Medical School, University of Warwick, Gibbet Hill Road, CV4 7AL Coventry, U.K
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Baker AN, Richards SJ, Pandey S, Guy CS, Ahmad A, Hasan M, Biggs CI, Georgiou PG, Zwetsloot AJ, Straube A, Dedola S, Field RA, Anderson NR, Walker M, Grammatopoulos D, Gibson MI. Glycan-Based Flow-Through Device for the Detection of SARS-COV-2. ACS Sens 2021; 6:3696-3705. [PMID: 34634204 PMCID: PMC8525701 DOI: 10.1021/acssensors.1c01470] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 09/23/2021] [Indexed: 12/12/2022]
Abstract
The COVID-19 pandemic, and future pandemics, require diagnostic tools to track disease spread and guide the isolation of (a)symptomatic individuals. Lateral-flow diagnostics (LFDs) are rapid and of lower cost than molecular (genetic) tests, with current LFDs using antibodies as their recognition units. Herein, we develop a prototype flow-through device (related, but distinct to LFDs), utilizing N-acetyl neuraminic acid-functionalized, polymer-coated, gold nanoparticles as the detection/capture unit for SARS-COV-2, by targeting the sialic acid-binding site of the spike protein. The prototype device can give rapid results, with higher viral loads being faster than lower viral loads. The prototype's effectiveness is demonstrated using spike protein, lentiviral models, and a panel of heat-inactivated primary patient nasal swabs. The device was also shown to retain detection capability toward recombinant spike proteins from several variants (mutants) of concern. This study provides the proof of principle that glyco-lateral-flow devices could be developed to be used in the tracking monitoring of infectious agents, to complement, or as alternatives to antibody-based systems.
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Affiliation(s)
| | | | - Sarojini Pandey
- Institute of Precision Diagnostics and Translational
Medicine, University Hospitals Coventry and Warwickshire NHS
Trust, Clifford Bridge Road, Coventry CV2 2DX,
U.K.
| | - Collette S. Guy
- Department of Chemistry, University of
Warwick, Coventry CV4 7AL, U.K.
- School of Life Sciences, University of
Warwick, Coventry CV4 7AL, U.K.
| | - Ashfaq Ahmad
- Department of Chemistry, University of
Warwick, Coventry CV4 7AL, U.K.
- Warwick Medical School, University of
Warwick, Coventry CV4 7AL, U.K.
| | - Muhammad Hasan
- Department of Chemistry, University of
Warwick, Coventry CV4 7AL, U.K.
- Warwick Medical School, University of
Warwick, Coventry CV4 7AL, U.K.
| | - Caroline I. Biggs
- Department of Chemistry, University of
Warwick, Coventry CV4 7AL, U.K.
| | | | | | - Anne Straube
- Warwick Medical School, University of
Warwick, Coventry CV4 7AL, U.K.
| | - Simone Dedola
- Iceni Diagnostics Ltd., Norwich
Research Park, Norwich NR4 7GJ, U.K.
| | - Robert A. Field
- Iceni Diagnostics Ltd., Norwich
Research Park, Norwich NR4 7GJ, U.K.
- Department of Chemistry and Manchester Institute of
Biotechnology, University of Manchester, Manchester M1 7DN,
U.K.
| | - Neil R. Anderson
- Institute of Precision Diagnostics and Translational
Medicine, University Hospitals Coventry and Warwickshire NHS
Trust, Clifford Bridge Road, Coventry CV2 2DX,
U.K.
| | - Marc Walker
- Department of Physics, University of
Warwick, Coventry CV4 7AL, U.K.
| | - Dimitris Grammatopoulos
- Warwick Medical School, University of
Warwick, Coventry CV4 7AL, U.K.
- Institute of Precision Diagnostics and Translational
Medicine, University Hospitals Coventry and Warwickshire NHS
Trust, Clifford Bridge Road, Coventry CV2 2DX,
U.K.
| | - Matthew I. Gibson
- Department of Chemistry, University of
Warwick, Coventry CV4 7AL, U.K.
- Warwick Medical School, University of
Warwick, Coventry CV4 7AL, U.K.
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Stinton C, Jordan M, Fraser H, Auguste P, Court R, Al-Khudairy L, Madan J, Grammatopoulos D, Taylor-Phillips S. Testing strategies for Lynch syndrome in people with endometrial cancer: systematic reviews and economic evaluation. Health Technol Assess 2021; 25:1-216. [PMID: 34169821 PMCID: PMC8273681 DOI: 10.3310/hta25420] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Lynch syndrome is an inherited genetic condition that is associated with an increased risk of certain cancers. The National Institute for Health and Care Excellence has recommended that people with colorectal cancer are tested for Lynch syndrome. Routine testing for Lynch syndrome among people with endometrial cancer is not currently conducted. OBJECTIVES To systematically review the evidence on the test accuracy of immunohistochemistry- and microsatellite instability-based strategies to detect Lynch syndrome among people who have endometrial cancer, and the clinical effectiveness and the cost-effectiveness of testing for Lynch syndrome among people who have been diagnosed with endometrial cancer. DATA SOURCES Searches were conducted in the following databases, from inception to August 2019 - MEDLINE ALL, EMBASE (both via Ovid), Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials (both via Wiley Online Library), Database of Abstracts of Reviews of Effects, Health Technology Assessment Database (both via the Centre for Reviews and Dissemination), Science Citation Index, Conference Proceedings Citation Index - Science (both via Web of Science), PROSPERO international prospective register of systematic reviews (via the Centre for Reviews and Dissemination), NHS Economic Evaluation Database, Cost-Effectiveness Analysis Registry, EconPapers (Research Papers in Economics) and School of Health and Related Research Health Utilities Database. The references of included studies and relevant systematic reviews were also checked and experts on the team were consulted. REVIEW METHODS Eligible studies included people with endometrial cancer who were tested for Lynch syndrome using immunohistochemistry- and/or microsatellite instability-based testing [with or without mutL homologue 1 (MLH1) promoter hypermethylation testing], with Lynch syndrome diagnosis being established though germline testing of normal (non-tumour) tissue for constitutional mutations in mismatch repair. The risk of bias in studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 tool, the Consolidated Health Economic Reporting Standards and the Philips' checklist. Two reviewers independently conducted each stage of the review. A meta-analysis of test accuracy was not possible because of the number and heterogeneity of studies. A narrative summary of test accuracy results was provided, reporting test accuracy estimates and presenting forest plots. The economic model constituted a decision tree followed by Markov models for the impact of colorectal and endometrial surveillance, and aspirin prophylaxis with a lifetime time horizon. RESULTS The clinical effectiveness search identified 3308 studies; 38 studies of test accuracy were included. (No studies of clinical effectiveness of endometrial cancer surveillance met the inclusion criteria.) Four test accuracy studies compared microsatellite instability with immunohistochemistry. No clear difference in accuracy between immunohistochemistry and microsatellite instability was observed. There was some evidence that specificity of immunohistochemistry could be improved with the addition of methylation testing. There was high concordance between immunohistochemistry and microsatellite instability. The economic model indicated that all testing strategies, compared with no testing, were cost-effective at a willingness-to-pay threshold of £20,000 per quality-adjusted life-year. Immunohistochemistry with MLH1 promoter hypermethylation testing was the most cost-effective strategy, with an incremental cost-effectiveness ratio of £9420 per quality-adjusted life-year. The second most cost-effective strategy was immunohistochemistry testing alone, but incremental analysis produced an incremental cost-effectiveness ratio exceeding £130,000. Results were robust across all scenario analyses. Incremental cost-effectiveness ratios ranged from £5690 to £20,740; only removing the benefits of colorectal cancer surveillance produced an incremental cost-effectiveness ratio in excess of the £20,000 willingness-to-pay threshold. A sensitivity analysis identified the main cost drivers of the incremental cost-effectiveness ratio as percentage of relatives accepting counselling and prevalence of Lynch syndrome in the population. A probabilistic sensitivity analysis showed, at a willingness-to-pay threshold of £20,000 per quality-adjusted life-year, a 0.93 probability that immunohistochemistry with MLH1 promoter hypermethylation testing is cost-effective, compared with no testing. LIMITATIONS The systematic review excluded grey literature, studies written in non-English languages and studies for which the reference standard could not be established. Studies were included when Lynch syndrome was diagnosed by genetic confirmation of constitutional variants in the four mismatch repair genes (i.e. MLH1, mutS homologue 2, mutS homologue 6 and postmeiotic segregation increased 2). Variants of uncertain significance were reported as per the studies. There were limitations in the economic model around uncertainty in the model parameters and a lack of modelling of the potential harms of gynaecological surveillance and specific pathway modelling of genetic testing for somatic mismatch repair mutations. CONCLUSION The economic model suggests that testing women with endometrial cancer for Lynch syndrome is cost-effective, but that results should be treated with caution because of uncertain model inputs. FUTURE WORK Randomised controlled trials could provide evidence on the effect of earlier intervention on outcomes and the balance of benefits and harms of gynaecological cancer surveillance. Follow-up of negative cases through disease registers could be used to determine false negative cases. STUDY REGISTRATION This study is registered as PROSPERO CRD42019147185. FUNDING This project was funded by the National Institute for Health Research (NIHR) Evidence Synthesis programme and will be published in full in Health Technology Assessment; Vol. 25, No. 42. See the NIHR Journals Library website for further project information.
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Affiliation(s)
- Chris Stinton
- Warwick Medical School, University of Warwick, Coventry, UK
| | - Mary Jordan
- Warwick Medical School, University of Warwick, Coventry, UK
| | - Hannah Fraser
- Warwick Medical School, University of Warwick, Coventry, UK
| | - Peter Auguste
- Warwick Medical School, University of Warwick, Coventry, UK
| | - Rachel Court
- Warwick Medical School, University of Warwick, Coventry, UK
| | | | - Jason Madan
- Warwick Medical School, University of Warwick, Coventry, UK
| | - Dimitris Grammatopoulos
- Institute of Precision Diagnostics and Translational Medicine, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK
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Papadopoulou A, Thymara I, Valsamakis G, Laryngaki A, Theodorou S, Papaevangelou V, Grammatopoulos D, Mastorakos G. SUN-635 Profiling of Activation Patterns of Placental mTOR in Pregnancies Complicated by Gestational Diabetes Mellitus. J Endocr Soc 2020. [PMCID: PMC7207272 DOI: 10.1210/jendso/bvaa046.1087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Abstract
The mammalian target of rapamycin (mTOR) couples’ energy and nutrient abundance to cell growth and is critically involved in the onset and progression of diabetes, cancer and ageing. Placental mTOR is involved in nutrient sensing and transfer to the fetus; animal models suggest that placental mTOR is upregulated in pregnancies complicated by hyperglycaemia (1). In this study we investigated expression patterns and activation of placental mTOR and possible effects of gestational diabetes (GDM). Our study consisted of GDM-mothers (n=28) and their offspring and ii) mothers (n=33) with normal pregnancies (non-GDM) and their infants. Total and phospho-mTOR (Ser2448) expression were determined in placental biopsies using either immunoblotting and immunohistochemistry (IHC) analysis. Newborn anthropometric parameters were also determined at delivery. GDM pregnant women presented with higher fasting glucose levels than non-GDM (98.12±22.82mg/dL; 73.61±9.89mg/dL; p<0.001). No significant difference was found in birth weight or baby length between GDM and non-GDM infants. IHC analysis showed that both total and activated mTOR were predominantly expressed in trophoblasts and to a lesser extend in syncytiotrophoblasts, in both GDM and non-GDM placentas. GDM placentas exhibited a higher mTOR H-score (2) compared to non-GDM (p<0.012), and WB analysis showed a higher phosphor-mTOR signal intensity (p=0.047) in the same group, most likely due to increased total mTOR expression. mTOR expression was also increased in both GDM syncytiotrophoblasts and endothelial cells compared to non-GDM (p<0.001) whereas a reduced signal was detected in stromal phospho-mTOR (p=0.004). No difference was found in trophoblasts or endothelial cells between the 2 study groups suggesting that activation of this kinase is tightly regulated and is relatively independent of changes in total kinase levels. Interestingly bivariate correlation analysis identified an extensive network of significant associations in the expression levels of total, phosphor-mTOR and P/T mTOR between trophoblasts, stroma, endothelial and syncytiotrophoblastsin control placental biopsies; this network was significantly disrupted in GDM placentas, identifying a disheveled regulation of placental mTOR activity. In conclusion, placental mTOR/PmTOR expression is differentially regulated across different placental cell types and is sensitive to hyperglycaemia associated with gestational diabetes mellitus.(1)M. Castillo-Castrejon and TL. Powell. Front Endocrinol (Lausanne). 2017; 8: 306. (2) E. Lakiotaki, et al., Scientific Reports 2016; 6, 21252.
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Affiliation(s)
- Anna Papadopoulou
- 3rd Department of Pediatrics, University General Hospital “Attikon”, Medical School, National and Kapodistrian University Athens, Athens, Greece
| | - Irene Thymara
- st Laboratory of Pathology, Medical School, University of Athens, School of Health Sciences, National and Kapodistrian University Athens, Athens, Greece
| | - Georgios Valsamakis
- Unit of Endocrinology, Diabetes mellitus and Metabolic diseases, Aretaeion Hospital, Medical School, National and Kapodistrian University Athens, Athens, Greece
| | - Anastasia Laryngaki
- 3rd Department of Pediatrics, University General Hospital “Attikon”, Medical School, National and Kapodistrian University Athens, Athens, Greece
| | - Spyridoula Theodorou
- 3rd Department of Pediatrics, University General Hospital “Attikon”, Medical School, National and Kapodistrian University Athens, Athens, Greece
| | - Vasiliki Papaevangelou
- 3rd Department of Pediatrics, University General Hospital “Attikon”, Medical School, National and Kapodistrian University Athens, Athens, Greece
| | - Dimitris Grammatopoulos
- Warwick Medical School and Institute of Precision Diagnostics and Translational Medicine, UHC NHS Trust, Coventry, United Kingdom
| | - Georgios Mastorakos
- Unit of Endocrinology, Diabetes mellitus and Metabolic diseases, Aretaeion Hospital, Medical School, National and Kapodistrian University Athens, Athens, Greece
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Panetta P, Zammit VA, Savvidou MD, Johnson MR, Grammatopoulos D. OR14-07 Association Between Placental Glucose Uptake and Protein O-Glcnacylation and Birth Outcomes in Obese Non-Diabetic Mothers. J Endocr Soc 2020. [PMCID: PMC7208252 DOI: 10.1210/jendso/bvaa046.925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Increased transport of nutrients such as glucose, across the placenta, has been linked to abnormal fetal growth and pregnancy complications in obese non-diabetic mothers (1); however, the underlying mechanisms are poorly understood. We hypothesized that in placenta, the metabolic and nutrient sensor O-GlcNAc transferase (OGT), highly sensitive to glucose flux through the hexosamine biosynthetic pathway (HBP), responds to maternal obesogenic environment by increasing O-GlcNAc post-translational modification of nucleocytoplasmic proteins in the placenta altering fetal growth trajectories. Tissue biopsies were isolated from placentas collected at term from 26 non-diabetic mothers alongside routine biochemistry and anthropometric data (maternal fasting glucose, glycated hemoglobin (HbA1c), early pregnancy body weight (BMI) and birth weight). OGT and glucose transporter 1 (GLUT1) protein expression as well as tissue levels of O-GlcNAcylation were determined by immunoblotting using specific antibodies. The BeWo choriocarcinoma cell line was also used as an in vitro model of trophoblast to test the effect of high glucose and GLUT1 silencing on the OGT activity by immunoblotting. Maternal BMI was positively correlated to birth weight centile (BWC) (p=0.0130, R2=0.231), maternal fasting glucose (p=0.0177, R2=0.221) and HbA1c levels (p= 0.0156, R2=0.229) as well as placental OGT protein expression (p=0.0294, R2=0.183). The latter was positively associated to the levels of protein O-GlcNAcylation (p=0.0023, R2=0.326). Interestingly, GLUT1 protein levels were positively correlated to BWC (p=0.0056, R2=0.279) and strongly correlated to protein O-GlcNAcylation (p<0.0001, R2=0.507), suggesting an increase in the placental flux of glucose. In agreement with findings in placenta biopsies, in BeWo cells total protein O-GlcNAcylation levels were altered by cell exposure to different glucose levels (5 mM vs 15 mM, p<0.01). This was prevented by downregulating OGT or GLUT1 expression (p<0.001) using gene silencing. In addition, OGT protein levels were negatively associated to AMP-activated protein kinase (AMPK) activation (p=0.0005, R2=0.402) in placenta biopsies identifying a novel cross-talk between two placental nutrient sensors, OGT and AMPK, previously shown in other tissues (2). Accordingly, the silencing of OGT promoted the activation of AMPK (p<0.01) and its downstream target acetyl-CoA carboxylase (ACC) (p<0.01) in BeWo cells, as demonstrated by increased phosphorylation of residues Thr172 and Ser79 for AMPK and ACC respectively. Such obesity-associated cross talk between metabolic and nutrient sensors might disrupt multiple cellular pathways involved in fetal development and growth. References: (1) Acosta et al. Am J Obstet Gynecol. 2015 Feb;212(2):227. (2) Bullen et al. J Biol Chem. 2014 Apr 11;289(15):10592-606.
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Affiliation(s)
| | | | | | | | - Dimitris Grammatopoulos
- Warwick Medical School and Institute of Precision Diagnostics and Translational Medicine, UHCW NHS Trust, Coventry, United Kingdom
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Braybrook E, English S, Sorinola O, Blacklay J, Forbes-Robertson S, Grammatopoulos D. SAT-026 Association of Inflammatory Markers with Depressive Symptoms Across the Perinatal Period. J Endocr Soc 2020. [PMCID: PMC7208604 DOI: 10.1210/jendso/bvaa046.901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Abstract
Perinatal depression (PND) is a mood disorder affecting 10-15% of women during pregnancy and postpartum. Its aetiology is complex with contribution from both genetic background and psychosocial as well as environmental stressors that determine individual responses shaped by chronic and acute disease burden (1). It is thought that the molecular basis of PND involves dysregulation of the HPA axis associated with neurotransmitter and neuroactive steroids imbalance. Inflammation appears to be a contributing mechanism, with increased levels of cytokines exerting adverse effects on serotonin metabolism, neuroplasticity and HPA hyperactivity (2). With only 50% of women detected through current screening strategies, there is an urgent unmet need for the development of biomarker-based strategies to identify women at risk of PND. In this study we used data and blood samples from the prospective Coventry and Warwickshire PND study; we investigated for inflammatory markers associated with depressive symptoms, assessed using the Edinburgh Postnatal Depression Score (EPDS) questionnaire between 24-29 weeks of gestation and again 6-10 weeks postpartum. A cut-off score of 10 categorize ‘high’ or ‘low’ risk for depression. Blood samples collected at 28 weeks of gestation were profiled for either IL-6 and IL-10 levels or a panel of 92 inflammatory markers. Individual inflammatory markers were compared across groups using Welch’s ANOVA. Results suggest that IL-10 levels were significantly correlated with EPDS score, exerting a protective effect (r= -.10), with reduced levels in the highest severity category (EPDS ≥ 15). The IL-6/IL-10 ratio was also associated with a raised EPDS score (r=.10, p=.01), as well as delivery complications (r=.09). The highest IL-6/IL-10 ratio is observed in women who had emergency caesarean section. Bayes’ theorem analysis suggested that IL-6/IL-10 ratio could be used as a negative screen to rule out low risk pregnancies. From the 92 inflammatory markers, 14 analytes were below the limit of detection for more than 50% of samples and so were excluded from further analysis. Upon comparison of groups determined by antenatal and postnatal EPDS scores, 29 markers displayed a significance value of P<0.05. Upon the application of post hoc tests, 8 markers including: STAM-BP, SIRT2, CD40, CASP8 and ADA, all associated with apoptotic processes, remained statistically significant in pregnant women with raised antenatal EPDS scores. This data support an association between inflammatory markers and perinatal depression and adverse pregnancy outcomes. Detailed quantitative analysis of such biomarker signatures at different stages of pregnancy, might lead to early detection of disease and application of targeted treatment. (1) Pariante, C. M. & Lightman, S. L. (2008) Trends Neurosci, 31 (9): 464-468. (2) Raison et al., (2006) Trends Immunol, 27 (1): 24-31.
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Affiliation(s)
- Emma Braybrook
- Warwick Medical School and Institute of Precision Diagnostics, UHCW NHS Trust, Coventry, United Kingdom, Coventry, United Kingdom
| | - Sarah English
- Warwick Medical School Coventry, United Kingdom, Coventry, United Kingdom
| | | | - Jayne Blacklay
- South Warwickshire NHS Foundation Trust, Warwick, United Kingdom
| | | | - Dimitris Grammatopoulos
- Univ of Warwick Medical School and Institute of Precision Diagnostics, UHCW NHS Trust, Coventry, United Kingdom, Coventry, United Kingdom
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Alcantara-Alonso V, Gortari PD, Dallmann R, Grammatopoulos D. SUN-267 Dissecting Type 2 CRH Receptor Signaling Characteristics in the Hypothalamic Cell Line MHYPOA-2/30. J Endocr Soc 2020. [PMCID: PMC7207635 DOI: 10.1210/jendso/bvaa046.1555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The stress peptides coticotropin-releasing hormone (CRH) and urocortins (Ucns) exert anorectic effects acting mainly through the type 2 CRH receptor (CRH-R2) in the hypothalamus. Impairment of CRH-R2 signaling in chronically stressed rats has been linked with the development of hyperphagia (Alcantara-Alonso et al. Neuropeptides, 2017) however the exact mechanisms and molecular defects are unknown. In the present study we used the mHypoA-2/30, a hypothalamic immortalized cell line derived from adult mice (Belsham et al. FASEB J, 2009) to further explore the signaling molecules mediating the anorexigenic effect of the CRH-R2 cognate agonist urocortin 2 (Ucn2). Specifically, we investigated mRNA, protein expression and cellular localization of CRH-R2 in the mHypoA-2/30 neurons. Additionally, we examined the effects of Ucn2 on the phosphorylation of CREB and AMPK, as well as its transcriptional effects on genes of feeding-related peptides and molecules involved in modulation of circadian rhythms. Both CRH-R2 mRNA and protein expression were detected in mHypoA-2/30; indirect immunoflourescence experiments using a specific CRH-R2 antibody demonstrated widespread localization in the plasma membrane and cytoplasm. Moreover, the receptor sub-cellular localization was redistributed in response to activation by Ucn2 (100 nM), as the plasma membrane immunofluorescent signal was decreased after 4h of agonist treatment, suggesting CRH-R2 homologous internalization. We also observed a 50% increase in the phosphorylation of CREB associated with a concomitant decrease in AMPK phosphorylation after 30 min of Ucn2 treatment. Among the panel of hypothalamic genes analyzed, we identified after 24h of Ucn2 treatment increases in the gene expression of the anorexigenic peptides neurotensin and proopiomelanocortin. Interestingly, sustained CRH-R2 activation also led to an increase in the mRNA levels of Aryl Hydrocarbon Receptor Nuclear Translocator Like (ARNTL), a protein involved in the control of circadian rhythm. A luciferase reporter gene analysis of ARNTL showed that the mHypoA-2/30 cells also exhibit circadian patterns of expression and that the treatment with Ucn2 enhanced circadian amplitude of ARNTL reporter on these cells, which in turn may be involved in glucocorticoid release in circadian cycles and stimulating appetite during the activity phase of the animals. In conclusion, we found that the mHypoA-2/30 cell line expresses endogenous functional CRH-R2 that is linked to downstream regulation of anorexigenic gene expression. This cell line appears to be a useful in vitro tool to study hypothalamic CRH-R2 signaling machinery involved in central control of food intake and circadian cycles.
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de Aguiar Greca SC, Kyrou I, Pink R, Randeva H, Grammatopoulos D, Silva E, Karteris E. Involvement of the Endocrine-Disrupting Chemical Bisphenol A (BPA) in Human Placentation. J Clin Med 2020; 9:jcm9020405. [PMID: 32028606 PMCID: PMC7074564 DOI: 10.3390/jcm9020405] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 01/22/2020] [Accepted: 01/23/2020] [Indexed: 12/16/2022] Open
Abstract
Background: Endocrine-disrupting chemicals (EDCs) are environmental chemicals/toxicants that humans are exposed to, interfering with the action of multiple hormones. Bisphenol A (BPA) is classified as an EDC with xenoestrogenic activity with potentially adverse effects in reproduction. Currently, a significant knowledge gap remains regarding the complete spectrum of BPA-induced effects on the human placenta. As such, the present study examined the effects of physiologically relevant doses of BPA in vitro. Methods: qRT-PCR, Western blotting, immunofluorescence, ELISA, microarray analyses, and bioinformatics have been employed to study the effects of BPA using nonsyncytialised (non-ST) and syncytialised (ST) BeWo cells. Results: Treatment with 3 nM BPA led to an increase in cell number and altered the phosphorylation status of p38, an effect mediated primarily via the membrane-bound estrogen receptor (GPR30). Nonbiased microarray analysis identified 1195 and 477 genes that were differentially regulated in non-ST BeWo cells, whereas in ST BeWo cells, 309 and 158 genes had altered expression when treated with 3 and 10 nM, respectively. Enriched pathway analyses in non-ST BeWo identified a leptin and insulin overlap (3 nM), methylation pathways (10 nM), and differentiation of white and brown adipocytes (common). In the ST model, most significantly enriched were the nuclear factor erythroid 2-related factor 2 (NRF2) pathway (3 nM) and mir-124 predicted interactions with cell cycle and differentiation (10 nM). Conclusion: Collectively, our data offer a new insight regarding BPA effects at the placental level, and provide a potential link with metabolic changes that can have an impact on the developing fetus.
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Affiliation(s)
| | - Ioannis Kyrou
- Aston Medical Research Institute, Aston Medical School, Aston University, Birmingham B4 7ET, UK;
- Warwickshire Institute for the Study of Diabetes, Endocrinology and Metabolism (WISDEM), University Hospitals Coventry and Warwickshire NHS Trust, Coventry CV2 2DX, UK
- Institute of Precision Diagnostics and Translational Medicine, UHCW NHS Trust, Coventry CV4 7AL, UK; (H.R.); (D.G.)
- Warwick Medical School, University of Warwick, Coventry CV4 7AL, UK
| | - Ryan Pink
- Dept of Bio. & Med. Sci., Oxford Brookes University, Oxford OX3 0BP, UK;
| | - Harpal Randeva
- Institute of Precision Diagnostics and Translational Medicine, UHCW NHS Trust, Coventry CV4 7AL, UK; (H.R.); (D.G.)
- Warwick Medical School, University of Warwick, Coventry CV4 7AL, UK
| | - Dimitris Grammatopoulos
- Institute of Precision Diagnostics and Translational Medicine, UHCW NHS Trust, Coventry CV4 7AL, UK; (H.R.); (D.G.)
- Warwick Medical School, University of Warwick, Coventry CV4 7AL, UK
| | - Elisabete Silva
- College of Health and Life Sciences, Brunel University London, Uxbridge UB8 3PH, UK;
- Correspondence: (E.S.); (E.K.)
| | - Emmanouil Karteris
- College of Health and Life Sciences, Brunel University London, Uxbridge UB8 3PH, UK;
- Correspondence: (E.S.); (E.K.)
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Geppert J, Stinton C, Johnson S, Clarke A, Grammatopoulos D, Taylor-Phillips S. Antenatal screening for fetal trisomies using microarray-based cell-free DNA testing: A systematic review and meta-analysis. Prenat Diagn 2019; 40:454-462. [PMID: 31834626 DOI: 10.1002/pd.5621] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 09/25/2019] [Accepted: 10/31/2019] [Indexed: 01/12/2023]
Abstract
OBJECTIVE To evaluate the test accuracy of non-invasive prenatal testing (NIPT) for fetal trisomy 21, 18, and 13 using cell-free (cf) DNA analysis in maternal plasma with microarray quantitation. METHOD Systematic review and meta-analysis. Searches in MEDLINE, Pre-MEDLINE, EMBASE, Web of Science, and the Cochrane Library to 09.07.2018. RESULTS Five studies analyzing 3074 samples, including 187 trisomy 21, 43 trisomy 18, and 19 trisomy 13 cases, were identified. Risk of bias was high in all studies, introduced particularly by exclusions from analysis and by the role of the sponsor. Sensitivity of microarray-based cfDNA testing was 99.5% (95%CI 96.3%-99.9%) for trisomy 21, 97.7% (95%CI 87.9%-99.6%) for trisomy 18, and 100% (95%CI 83.2%-100%) for trisomy 13. Specificity was 100% (95% CI 99.87%-100%) for trisomy 21, 99.97% (95%CI 99.81%-99.99%) for trisomy 18, and 99.97% (95%CI 99.81%-99.99%) for trisomy 13. Pooled test failure rate was 1.1%. A direct comparison of microarray- and sequencing-based cfDNA found equivalent test accuracy. CONCLUSION Included studies suggest that NIPT using microarray-based cfDNA testing has high sensitivity and specificity for detecting fetal trisomy 21, 18, and 13. However, the evidence base is small and at high risk of bias.
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Affiliation(s)
- Julia Geppert
- Warwick Medical School, University of Warwick, Coventry, UK
| | - Chris Stinton
- Warwick Medical School, University of Warwick, Coventry, UK
| | | | - Aileen Clarke
- Warwick Medical School, University of Warwick, Coventry, UK
| | - Dimitris Grammatopoulos
- Warwick Medical School, University of Warwick, Coventry, UK.,Institute of Precision Diagnostics and Translational Medicine, University Hospital Coventry & Warwickshire (UHCW) NHS Trust, Coventry, UK
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Chawla A, Paraoan V, Rabiu R, Clark T, Powell S, Grammatopoulos D, Armitage C, Penedo A, Havard A, Metcalfe A, Barlow T, Khatri C. Determining the stress biomarker profile in patients undergoing total knee replacement and the relationship with outcome at 12 months. Knee 2019; 26:1379-1385. [PMID: 31575511 DOI: 10.1016/j.knee.2019.08.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 08/06/2019] [Accepted: 08/26/2019] [Indexed: 02/02/2023]
Abstract
BACKGROUND Total knee replacement (TKR) is the commonest joint arthroplasty procedure worldwide. Despite excellent outcomes, some studies have reported dissatisfaction in up to 20% of patients. There is evidence of an association between the biochemical stress response to surgery and outcomes. The objective of this study is to describe the stress biomarker profile for TKR, and correlate this with patient outcomes. METHODS A prospective cohort study of 50 patients undergoing primary TKR was conducted. Serum IL-6, TNF-α, neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) were measured immediately pre- and post-operatively, and on Days 1 and 3. Follow-up questionnaires including the Oxford Knee Score (OKS) and EuroQol five dimensions (EQ-5D) were completed at 12-months. Univariate analysis was completed using a linear regression model (p < 0.05). RESULTS Serum IL-6, NLR, and PLR all increased to Day 1 post-operatively, and decreased by Day 3. TNF-α values increased across all time points. Statistical analysis found a significant negative correlation (r = -0.414; p = 0.005) between pre-operative IL-6 and 12-month OKS. There was a significant positive correlation between pre-operative NLR and 12 month OKS (r = 0.272; p = 0.039) and 12 month EQ5D (r = 0.268; p = 0.043). CONCLUSION This is the first study to describe the biochemical stress response to TKR. The results raise the potential for a pre-operative risk stratification tool for patients based on IL-6 and NLR measurements. Further research should be conducted to explore the underlying mechanisms involved, and investigate interventions to reduce pre-operative physiological stress with a view to improving post-operative outcomes.
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Affiliation(s)
- Amit Chawla
- Clinical Trials Unit, University of Warwick Medical School, Coventry, UK.
| | - Vlad Paraoan
- Clinical Trials Unit, University of Warwick Medical School, Coventry, UK
| | - Rasheed Rabiu
- Clinical Trials Unit, University of Warwick Medical School, Coventry, UK
| | - Tamsyn Clark
- Clinical Trials Unit, University of Warwick Medical School, Coventry, UK
| | - Sam Powell
- University of Warwick Medical School, Coventry, UK
| | - Dimitris Grammatopoulos
- Division of Translational and Experimental Medicine, Warwick Medical School, UK; Institute of Precision Diagnostics and Translational Medicine, Department of Pathology, University Hospitals Coventry and Warwickshire NHS Trust, UK
| | - Charlotte Armitage
- Clinical Biochemistry, Department of Pathology, University Hospitals Coventry and Warwickshire NHS Trust, UK
| | - Ana Penedo
- Clinical Biochemistry, Department of Pathology, University Hospitals Coventry and Warwickshire NHS Trust, UK
| | - Alwyn Havard
- Alwyn Havard and Associates, Animal & Avian Bio Sciences, Broadway, UK
| | - Andrew Metcalfe
- Clinical Trials Unit, University of Warwick Medical School, Coventry, UK
| | - Tim Barlow
- Clinical Trials Unit, University of Warwick Medical School, Coventry, UK
| | - Chetan Khatri
- Clinical Trials Unit, University of Warwick Medical School, Coventry, UK
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Kyrou I, Adesanya O, Hedley N, Wayte S, Grammatopoulos D, Thomas CL, Weedall A, Sivaraman S, Pelluri L, Barber TM, Menon V, Randeva HS, Tedla M, Weickert MO. Improved Thyroid Hypoechogenicity Following Bariatric-Induced Weight Loss in Euthyroid Adults With Severe Obesity-a Pilot Study. Front Endocrinol (Lausanne) 2018; 9:488. [PMID: 30197625 PMCID: PMC6117911 DOI: 10.3389/fendo.2018.00488] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 08/06/2018] [Indexed: 01/04/2023] Open
Abstract
Background: Obesity may affect both biochemical thyroid function tests; and thyroid morphology, as assessed using ultrasound scans (US). The aim of the present pilot study was to explore whether weight loss achieved by bariatric surgery alters thyroid US morphology including gray-scale measurements; and/or function in euthyroid adults with severe obesity. Methods: Euthyroid adults (>18 years) with body mass index (BMI) ≥40 kg/m2 and negative thyroid peroxidase antibodies were assessed at baseline (pre-surgery) and after achieving at least 5% weight loss of their baseline body weight following bariatric surgery. Anthropometric assessments, biochemical/hormonal measurements (TSH, free-T4, free-T3, reverse-T3, and leptin) and thyroid US with gray-scale histogram analysis were performed at the baseline and post-surgery follow-up. Results: Ten Caucasian, euthyroid patients (women/men: 8/2; age: 48.6 ± 3.1 years; BMI: 51.4 ± 1.8 kg/m2) successfully completed this study with significantly decreased body weight (>5% weight loss), waist circumference and serum leptin levels post-surgery (mean post-surgery follow-up duration: 16.5 ± 2.5 months). In parallel to the observed bariatric-induced weight loss, thyroid US echogenicity increased by 25% (p = 0.03), without significant changes in thyroid volume. No significant changes in thyroid function tests were detected. No significant correlations were observed between the increase in thyroid echogenicity and the decreases in anthropometric parameters and circulating leptin. Conclusion: Our results indicate that in euthyroid adults with severe obesity, marked weight loss achieved by bariatric surgery is associated with a parallel significant increase in the thyroid US echogenicity, suggesting that morphological changes of the thyroid in obesity are reversible with weight loss. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT03048708.
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Affiliation(s)
- Ioannis Kyrou
- Aston Medical Research Institute, Aston Medical School, Aston University, Birmingham, United Kingdom
- Warwickshire Institute for the Study of Diabetes, Endocrinology and Metabolism, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, United Kingdom
- Translational and Experimental Medicine, Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, United Kingdom
- Centre of Applied Biological and Exercise Sciences, Faculty of Health and Life Sciences, Coventry University, Coventry, United Kingdom
| | - Olu Adesanya
- Department of Radiology, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, United Kingdom
| | - Nicholas Hedley
- Department of Radiology, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, United Kingdom
| | - Sarah Wayte
- Radiology Physics Department, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, United Kingdom
| | - Dimitris Grammatopoulos
- Translational and Experimental Medicine, Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, United Kingdom
- Department of Pathology, Institute of Precision Diagnostics and Translational Medicine, University Hospital Coventry and Warwickshire NHS Trust, Coventry, United Kingdom
| | - Claire L. Thomas
- Department of Clinical Biochemistry, University Hospital Coventry and Warwickshire NHS Trust, Coventry, United Kingdom
| | - Andrew Weedall
- Radiology Physics Department, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, United Kingdom
| | - Subash Sivaraman
- Warwickshire Institute for the Study of Diabetes, Endocrinology and Metabolism, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, United Kingdom
| | - Lavanya Pelluri
- Warwickshire Institute for the Study of Diabetes, Endocrinology and Metabolism, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, United Kingdom
| | - Thomas M. Barber
- Warwickshire Institute for the Study of Diabetes, Endocrinology and Metabolism, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, United Kingdom
- Translational and Experimental Medicine, Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, United Kingdom
| | - Vinod Menon
- Department of Surgery, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, United Kingdom
| | - Harpal S. Randeva
- Aston Medical Research Institute, Aston Medical School, Aston University, Birmingham, United Kingdom
- Warwickshire Institute for the Study of Diabetes, Endocrinology and Metabolism, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, United Kingdom
- Translational and Experimental Medicine, Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, United Kingdom
- Centre of Applied Biological and Exercise Sciences, Faculty of Health and Life Sciences, Coventry University, Coventry, United Kingdom
| | - Miroslav Tedla
- Warwickshire Institute for the Study of Diabetes, Endocrinology and Metabolism, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, United Kingdom
- Department of ENT and Head and Neck Surgery, Faculty of Medicine, Comenius University, Bratislava, Slovakia
| | - Martin O. Weickert
- Warwickshire Institute for the Study of Diabetes, Endocrinology and Metabolism, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, United Kingdom
- Translational and Experimental Medicine, Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, United Kingdom
- Centre of Applied Biological and Exercise Sciences, Faculty of Health and Life Sciences, Coventry University, Coventry, United Kingdom
- *Correspondence: Martin O. Weickert
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Kandala NB, Engineer N, Grammatopoulos D. Authors response to Stergiakouli et al. J Psychiatr Res 2014; 56:171-2. [PMID: 24838048 DOI: 10.1016/j.jpsychires.2014.04.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Revised: 04/22/2014] [Accepted: 04/22/2014] [Indexed: 10/25/2022]
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Smith R, Van Helden D, Hirst J, Zakar T, Read M, Chan EC, Palliser H, Grammatopoulos D, Nicholson R, Parkington HC. Pathological interactions with the timing of birth and uterine activation. Aust N Z J Obstet Gynaecol 2008; 47:430-7. [PMID: 17991105 DOI: 10.1111/j.1479-828x.2007.00775.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The physiological processes that regulate the onset of parturition and birth are slowly being elucidated, and the points at which pathology can intervene are becoming more apparent. The data support the view that multiple pathways lead to myometrial activation. The clinical corollary is that combinations of tocolytics that operate via different mechanisms may be more effective than single agents. It may also be necessary to divide preterm labour into groups based on underlying mechanisms and to tailor therapy accordingly.
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Affiliation(s)
- Roger Smith
- Mothers and Babies Research Centre, Hunter Medical Research Institute, John Hunter Hospital, and School of Biomedical Sciences, University of Newcastle, New South Wales, Australia.
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Karteris E, Hillhouse EW, Grammatopoulos D. Urocortin II is expressed in human pregnant myometrial cells and regulates myosin light chain phosphorylation: potential role of the type-2 corticotropin-releasing hormone receptor in the control of myometrial contractility. Endocrinology 2004; 145:890-900. [PMID: 14592950 DOI: 10.1210/en.2003-1210] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The family of CRH-related peptides are suggested to play important roles in the control of myometrial contractility during pregnancy and labor. In this study we investigated the expression of urocortin II (UCN II) in human myometrium and its ability to phosphorylate intracellular components that can be involved in modulating myometrial contractility. Using RT-PCR and fluorescent in situ hybridization, we demonstrated that UCN II and type-2 CRH receptor (CRH-R2) mRNAs were expressed in human nonpregnant and pregnant myometrium. Immunofluorescent studies confirmed protein expression of UCN II in human pregnant myometrial cells, whereas chemical cross-linking studies with radiolabeled UCN II confirmed the presence of CRH-R2 sites with an apparent molecular mass of 50 kDa. Treatment of primary human myometrial cells with UCN II to specifically activate CRH-R2 resulted in a dose-dependent increase of myosin light chain (MLC(20)) phosphorylation. Activation of protein kinase C (PKC) and ERK1/2 was required for the UCN II-induced activation of MLC(20), because treatment of myometrial cells with inhibitors of MAPK kinase 1 (U0126) and PKC (bisindolylmaleimide) inhibited the UCN II-induced phosphorylation of MLC(20). Furthermore, the UCN II effect on MLC(20) was dependent on RhoA translocation to the membrane and subsequent activation of RhoA-associated kinase, as shown by the use of the specific inhibitors exoenzyme C3 and Y27632. Collectively, our data suggest a distinctive role for CRH-R2- specific agonists like UCN II in the control of myometrial contractility during human pregnancy involving sequential activation of PKC, MAPK kinase 1, ERK1/2, RhoA, and RhoA-associated kinase, leading to the MLC(20) phosphorylation.
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Affiliation(s)
- Emmanouil Karteris
- Biomedical Research Institute, Department of Biological Sciences, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, United Kingdom
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Grammatopoulos D, Elliott Y, Smith SC, Brown I, Grieve RJ, Hillhouse EW, Levine MA, Ringel MD. Measurement of thyroglobulin mRNA in peripheral blood as an adjunctive test for monitoring thyroid cancer. Mol Pathol 2003; 56:162-6. [PMID: 12782763 PMCID: PMC1187312 DOI: 10.1136/mp.56.3.162] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AIMS Monitoring treated patients with thyroid cancer for recurrent or metastatic disease is currently based upon the serial measurement of circulating plasma thyroglobulin (Tg) concentrations. However, the clinical usefulness of Tg immunoassays is limited by poor sensitivity and interference from anti-Tg antibodies. This study investigated whether the detection of Tg mRNA in peripheral blood, using reverse transcriptase polymerase chain reaction (RT-PCR), is of value in the biochemical surveillance of patients with thyroid cancer. METHODS RNA was extracted from peripheral blood of five normal controls, six patients with abnormal thyroid function tests, and 28 patients who had undergone thyroidectomy for well differentiated thyroid cancer. From each, an 87 bp product from base pair 262 to 348 in the cDNA sequence of the thyroglobulin gene was amplified by RT-PCR. RESULTS Tg mRNA was detected in normal individuals and patients with thyroid cancer. In the group of patients studied, identification of metastatic thyroid tissue by radioiodine scanning correlated better with Tg mRNA assay results than with serum Tg concentrations (accuracy 84% v 75%). No interference from circulating Tg antibodies was apparent. In patients studied prospectively over a 12 month period, there was a significant correlation between detectable Tg mRNA in peripheral blood and the presence or absence of metastatic disease, as demonstrated by radioiodine scanning. CONCLUSIONS These results suggest that detection of Tg mRNA in blood is a more sensitive marker for metastatic thyroid disease than Tg immunoassay, and appears to be unaffected by the presence of circulating anti-Tg antibodies.
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Affiliation(s)
- D Grammatopoulos
- Molecular Medicine Research Centre, Department of Biological Sciences, University of Warwick, Coventry CV4 7AL, UK.
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Abstract
Corticotropin-releasing hormone (CRH) and related peptides (urocortins, sauvagine, urotensin) play a central role in the co-ordination of autonomic, behavioural, cardiovascular, immune and endocrine responses to stressful stimuli. Their actions are mediated through activation of two types of G-protein-coupled receptors encoded by separate genes. In this review we focus on the diverse structural and functional characteristics of the family of CRH-like peptides and their receptors.
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Affiliation(s)
- E W Hillhouse
- Molecular Medicine Research Centre, Department of Biological Sciences, University of Warwick, Coventry CV4 7AL, UK.
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Randeva HS, Karteris E, Grammatopoulos D, Hillhouse EW. Expression of orexin-A and functional orexin type 2 receptors in the human adult adrenals: implications for adrenal function and energy homeostasis. J Clin Endocrinol Metab 2001; 86:4808-13. [PMID: 11600545 DOI: 10.1210/jcem.86.10.7921] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The hypothalamic peptides, orexin-A and orexin-B, have been implicated in the regulation of feeding behavior. In starved rats catabolic activity quickly predominates, reinforced by elevated corticosterone, independent of ACTH, implicating adrenal activity as a metabolic regulator. In view of these findings, we investigated whether orexin and orexin receptors are present in human adult adrenals and might therefore be implicated in hormonal regulation and energy homeostasis outside the central nervous system. RT-PCR, fluorescent in situ hybridization, immunoblotting, and immunostaining analysis confirmed the expression of the orexin type 2 receptor, but not of orexin type 1 receptor, in the adrenal cortex. Immunoblotting analysis also detected the presence of the prepro-orexin and its cleaved product orexin-A. Treatment of adult adrenal membranes with orexin-A increased the labeling of G(s), G(q), and, to a lesser degree, G(i), but not G(o). Stimulation with orexin-A induced cAMP and IP3 production in a dose-dependent manner. The data presented here provide conclusive evidence for the presence of orexin-A and orexin type 2 receptors in human adult adrenal glands. At the moment the functional relevance of this is uncertain. However, it is known that both orexin-A and orexin-B can induce corticosterone production in dispersed rat adrenocortical cells. Our data provide further evidence for a functional link between orexogenic signals and adrenal function. The concept that the peptide acting via these receptors in the adult adrenal is responsible for steroidogenesis and energy balance is attractive.
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Affiliation(s)
- H S Randeva
- Sir Quinton Hazel Molecular Medicine Research Center, Department of Biological Sciences, University of Warwick, Coventry, United Kingdom CV4 7AL.
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Karteris E, Grammatopoulos D, Randeva H, Hillhouse EW. Signal transduction characteristics of the corticotropin-releasing hormone receptors in the feto-placental unit. J Clin Endocrinol Metab 2000; 85:1989-96. [PMID: 10843186 DOI: 10.1210/jcem.85.5.6590] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Placentally derived CRH plays a major role in the mechanisms controlling human pregnancy and parturition. In this study, we sought to investigate the signal transduction mechanisms of CRH Type-1 receptors in the feto-placental unit. To clarify the signal transduction components in placenta and fetal membranes, we investigated the expression of G proteins and adenylate cyclase. Using the nonhydrolysable photoreactive analog [alpha-32P] GTP-azidoanilide and peptide antisera raised against G protein alpha-subunits, we studied coupling of CRH receptors to G proteins in both placental and fetal membranes. Treatment of placental membranes with human CRH (100 nM) increased the labeling of Gq, Go, and Gz but not Gi and Gs. Treatment of fetal membranes with human CRH (100 nM) increased the labeling of Go and Gq but not Gi, Gs, and Gz. These results were supported by experiments that showed that CRH failed to activate adenylate cyclase in these tissues, but induced an increase in inositol phosphates instead. These findings provide new insights into the components of the signal transduction machinery in both fetal and placental membranes and suggest that CRH Type-1 receptors can couple to different G proteins in different tissues. The physiological significance of these observations remains to be elucidated.
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Affiliation(s)
- E Karteris
- The Sir Quinton Hazel Research Centre for Molecular Medicine, Department of Biological Sciences, University of Warwick, Coventry, United Kingdom
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Grammatopoulos D, Dai Y, Chen J, Karteris E, Papadopoulou N, Easton AJ, Hillhouse EW. Human corticotropin-releasing hormone receptor: differences in subtype expression between pregnant and nonpregnant myometria. J Clin Endocrinol Metab 1998; 83:2539-44. [PMID: 9661640 DOI: 10.1210/jcem.83.7.4985] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
There is increasing evidence that CRH, which is the principal neuroregulator of the hypothalamic-pituitary-adrenocortical axis, is also involved in the mechanism of human labor. The human myometrium has been shown to express several high affinity CRH receptors, although the identities of the CRH receptor subtypes have yet to be identified. To investigate further the expression of the CRH receptor in human myometrium, we used RT-PCR, fluorescent in situ hybridization and immunofluorescence to identify and localize the four subtypes, 1 alpha, 1 beta, 2 alpha, and the variant C, of the CRH receptor. Interestingly, the CRH receptor subtypes in myometrium exhibit differential expression patterns; in human pregnant myometrium at term all four receptor-subtypes were expressed, whereas only the 1 alpha- and 1 beta-receptor subtypes were found in the nonpregnant myometrium. This would suggest that CRH, acting via different receptor subtypes, is able to exert different actions on the myometrium in the pregnant state compared to the nonpregnant state. Furthermore, in the pregnant human uterus, CRH receptors were localized in both smooth muscle and fibroblasts. These findings suggest that CRH receptor expression plays an important modulatory role in myometrial and possibly in cervical function.
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Affiliation(s)
- D Grammatopoulos
- Sir Quinton Hazell Molecular Medicine Research Center, Department of Biological Sciences, University of Warwick, Coventry, United Kingdom
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Karteris E, Grammatopoulos D, Dai Y, Olah KB, Ghobara TB, Easton A, Hillhouse EW. The human placenta and fetal membranes express the corticotropin-releasing hormone receptor 1alpha (CRH-1alpha) and the CRH-C variant receptor. J Clin Endocrinol Metab 1998; 83:1376-9. [PMID: 9543169 DOI: 10.1210/jcem.83.4.4705] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Placentally derived CRH plays a major role in the mechanisms controlling human pregnancy and parturition. It has been suggested that there is a CRH placental clock that is active from the early stages of pregnancy and determines the length of gestation and the timing of parturition. CRH can influence human reproductive tissue function via specific CRH receptors. Two distinct CRH receptors have been cloned (R1 and R2) that share 70% homology at the amino acid level and exist as two alternatively spliced forms (alpha and beta). In this study we investigated the presence of CRH receptor subtypes in human fetal membranes derived from spontaneous rupture and placental biopsies at term. Using RT-PCR, we identified the full length of the CRH-R1alpha subtype in placental and fetal membranes. In both tissues we also identified a spliced variant of the CRH receptor (CRH-Rc). We were unable to detect any CRH-R2 messenger ribonucleic acid in any of the biopsies. Fluorescent in situ hybridization and immunofluorescence in both tissues demonstrated that syncytiotrophoblast cells and amniotic epithelium are the major cell types expressing CRH-1alpha and CRH-Rc receptor messenger ribonucleic acid. Further studies are necessary to give a better insight into the role of CRH and its receptors in these tissues.
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Affiliation(s)
- E Karteris
- The Sir Quinton Hazell Research Center for Molecular Medicine, Department of Biological Sciences, University of Warwick, Coventry, United Kingdom
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Abstract
We have solubilized an active form of the myometrial corticotrophin-releasing hormone (CRH) receptor using 1% w/v digitonin. The solubilized receptor retains its capacity for high-affinity binding as demonstrated by Scatchard analysis, although there was a shift in dissociation constant (Kd) from 83.6 +/- 15-195 +/- 35 pM for the membrane-bound and soluble receptor respectively. There was no difference in the maximum binding site concentrations (Bmax) of 13 +/- 5 and 21.5 +/- 6 fmol/mg protein for the membrane-bound and soluble receptor respectively. Sauvagine unlike CRH had no effect on radiolabeled CRH binding which suggests that the CRH-R2 receptor is not present in the myometrium. The solubilized receptor did not retain guanine-nucleotide sensitivity. The isoelectric focusing (IEF) profile of the human myometrial CRH receptors was significantly different from that of the rat cerebral cortex. Furthermore, solubilization of human myometrial membrane proteins followed by gel filtration and SDS-PAGE revealed a specifically labeled protein with an apparent molecular weight of 42000-47000 kDa. Our results suggest that during solubilization the human myometrial CRH receptor is dissociated from the guanine nucleotide-binding protein (Gs) and that high affinity binding for soluble CRH receptors is not dependent on the coupling of a guanine nucleotide-binding protein.
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Affiliation(s)
- D Grammatopoulos
- Department of Biological Sciences, The University of Warwick, Coventry, UK
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Grammatopoulos D, Stirrat GM, Williams SA, Hillhouse EW. The biological activity of the corticotropin-releasing hormone receptor-adenylate cyclase complex in human myometrium is reduced at the end of pregnancy. J Clin Endocrinol Metab 1996; 81:745-51. [PMID: 8636298 DOI: 10.1210/jcem.81.2.8636298] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
We recently suggested that placentally derived CRH might influence human parturition via specific receptor mechanisms. We identified a human myometrial CRH receptor that changes to a high affinity state in the later stages of pregnancy and becomes coupled to the adenylate cyclase system. The purpose of this study was to investigate the functional capacity of this receptor in myometrial tissue obtained from women being delivered electively by cesarian section at term (38-40 weeks gestation) and preterm (30-35 weeks gestation) before the onset of labor. Myometrial membrane suspensions were prepared by differential centrifugation, and the production of cAMP after stimulation with various test substances was measured by RIA. In preterm myometrium, both human CRH and cholera toxin stimulated cAMP production. This effect was significantly reduced in term myometrium. The adenylate cyclase was functionally active in term myometrium, as demonstrated by the use of forskolin. Furthermore, pertussis toxin pretreatment of term myometrial membranes did not increase the response to CRH. These results suggest that in human pregnant myometrium at term, there is a modification in the coupling mechanisms between CRH receptors and the catalytic component of adenylate cyclase, resulting in a reduction of CRH-stimulated cAMP production.
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Affiliation(s)
- D Grammatopoulos
- Department of Medicine, University of Bristol, Bristol Royal Infirmary, United Kingdom
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Abstract
Specific high affinity binding sites for CRH have been identified and characterized in the pituitary and central nervous system as well as in peripheral tissues. We recently identified and characterized a specific CRH receptor in human myometrium that changes to a high affinity state before term. In view of this, we searched for receptor heterogeneity in the pregnant and nonpregnant human myometrial CRH receptor. Myometrial membranes were prepared by differential centrifugation from either pregnant (cesarian section) or nonpregnant (hysterectomy) myometrium. Using a specific RRA followed by isoelectric focusing and autoradiography, multiple isoforms of the human myometrial CRH receptor were identified that were identical in both pregnant and nonpregnant myometrium. Five isoforms were identified (pI 4.65, 4.8, 4.95, 5.1, and 5.2). Reduction of disulfide bridges with reducing agents (dithiothreitol and cysteine) increased the specific binding of CRH to its myometrial receptor, and the action of dithiothreitol affected the two most basic receptor isoforms. These results suggest the presence of multiple isoforms of CRH receptors that may have different properties and functions and the presence of disulfide bridges within the myometrial CRH receptor, which are important, but not critical, for the receptor binding.
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Affiliation(s)
- D Grammatopoulos
- Department of Clinical Biochemistry and Metabolic Medicine, University of Newcastle upon Tyne, United Kingdom
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Abstract
The initiation of human parturition remains an enigma but is thought to involve a number of hormonal signals such as oxytocin and prostaglandins. One other possible signal is placentally derived corticotropin-releasing hormone (CRH). We have recently reported that the human myometrium expresses a specific receptor for CRH which changes to a high affinity state prior to term. In view of this we sought to determine whether this receptor is functionally linked to some of the known modulators of myometrial function. Myometrial membranes were prepared by differential centrifugation from either pregnant (caesarian section) or non-pregnant (hysterectomy) myometrium. For binding studies the membranes were incubated with radiolabelled oCRH at 22 degrees C for 2 h. For second messenger studies they were incubated at 37 degrees C for 10 or 30 min with either 0.5 mM ATP and 10 mM theophylline (cAMP) or 0.05 mM arachidonic acid or 0.5 mM linoleic acid (PGE2). When increasing concentrations of membranes were incubated with radiolabelled oCRH an interesting phenomenon was observed. In non-pregnant membranes the binding reached a plateau, whereas in membranes prepared from pregnant myometrium, the binding decreased at concentrations above 130 micrograms/ml. Possible explanations for this phenomenon include an inhibitor which prevents ligand-receptor binding or an enzyme which destroys the receptor binding region of the ligand. Incubation of both types of membranes with GTP or its analogue, GppNHp, resulted in a dose-dependent inhibition of specific binding suggesting that the myometrial CRH receptor is linked to a G regulatory protein.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- D Grammatopoulos
- Department of Clinical Biochemistry, University of Newcastle upon Tyne, The Medical School, UK
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Hillhouse EW, Grammatopoulos D, Milton NG, Quartero HW. The identification of a human myometrial corticotropin-releasing hormone receptor that increases in affinity during pregnancy. J Clin Endocrinol Metab 1993; 76:736-41. [PMID: 8383145 DOI: 10.1210/jcem.76.3.8383145] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The concentration of immunoreactive, placentally derived CRH is increased in the peripheral circulation during the third trimester of human pregnancy. However, the function of this placental CRH is entirely unknown. A number of observations have led us to believe that CRH might influence myometrial contractility and, hence, parturition via specific receptor mechanisms. 1) In idiopathic preterm labor, plasma immunoreactive-CRH concentrations are significantly elevated compared to control values. 2) CRH and oxytocin exhibit a marked synergistic effect on myometrial contractility which is prostaglandin dependent and can be inhibited by the CRH receptor antagonist [alpha-helical CRF-(9-41)]. In view of this, we searched for specific CRH-binding sites in myometrial tissue obtained at biopsy from pregnant (cesarian section) and nonpregnant (hysterectomy) patients. To test for the presence of CRH receptors, we prepared myometrial membranes and performed binding studies using [125I]tyr-o-CRH as a ligand. The binding was found to be pH, time, temperature, and divalent cation concentration dependent and was fully reversible on addition of 1 microM unlabeled ovine CRH. In both tissues, there was a single, specific, homogenous, high affinity population of CRH receptors. Scatchard analysis of the specific binding sites revealed dissociation constants of 250-300 and 30-60 pM for the nonpregnant and pregnant myometrium, respectively. This compares with dissociation constants of 130 pM (rat anterior pituitary receptor) and 100 pM (human CRH-binding protein). This would mean that in the nonpregnant state, the equilibrium for binding is in favor of the binding protein, but during the later stages of pregnancy, the change in affinity of the receptor alters the binding in favor of the myometrial receptor.
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Affiliation(s)
- E W Hillhouse
- Department of Clinical Biochemistry and Metabolic Medicine, University of Newcastle, United Kingdom
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Papadoyannis I, Arzoglou P, Asvesta S, Grammatopoulos D, Lazaridis A. Rapid Simultaneous Determination For Catecholamines By Reversed-Phase High-Performance Liquid Chromatography. ANAL LETT 1989. [DOI: 10.1080/00032718908051348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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