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Fossum M, Kaefer M, Herbst KW, Harper L, Beckers GMA, Nelson CP, Garriboli M, Nieuwhof-Leppink A, Bagli D, Kalfa N. The orchestration of gene expression and the editing role of microRNA. J Pediatr Urol 2022:S1477-5131(22)00631-3. [PMID: 36653199 DOI: 10.1016/j.jpurol.2022.12.016] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 12/22/2022] [Indexed: 12/31/2022]
Abstract
In this short educational communication the ESPU Research Committee presents the role of non-coding RNA and how these can affect gene expression. In particular we discuss the role of microRNA on post transcriptional changes and how these may cause pathological conditions within Pediatric Urology and how microRNA could be useful in future clinical practice.
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Affiliation(s)
- M Fossum
- Department of Pediatric Surgery, Rigshospitalet, Dept of Medical Sciences, Copenhagen University, Copenhagen, Denmark; Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden.
| | - M Kaefer
- Riley Hospital for Children, Indiana University, Indianapolis, IN, United States
| | - K W Herbst
- Division of Urology, Department of Research, Connecticut Children's Medical Center, Hartford, CT, United States
| | - L Harper
- Service de Chirurgie Pédiatrique, Hôpital Pellegrin-Enfants, CHU de Bordeaux, France
| | | | - C P Nelson
- Department of Urology, Boston Children's Hospital and Department of Surgery, Harvard Medical School, Harvard University, Boston, MA, USA
| | - M Garriboli
- Department of Paediatric Urology, Evelina Children's Hospital, Guy's and St. Thomas NHS Foundation Trust, London, United Kingdom
| | - A Nieuwhof-Leppink
- University Medical Center Utrecht, Wilhelmina Children's Hospital, Utrecht, Netherlands
| | - D Bagli
- Division of Urology, Departments of Surgery and Physiology, University of Toronto, Developmental and Stem Cell Biology, The Hospital for Sick Children and Research Institute, Toronto, Ontario, Canada
| | - N Kalfa
- Service de Chirurgie Urologique Pédiatrique, Hôpital Lapeyronie, CHU de Montpellier, Université de Montpellier, France; Institut Debrest de Santé Publique IDESP, UMR INSERM - Université Montpellier, Montpellier, France
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Codd V, Denniff M, Swinfield C, Warner SC, Papakonstantinou M, Sheth S, Nanus DE, Budgeon CA, Musicha C, Bountziouka V, Wang Q, Bramley R, Allara E, Kaptoge S, Stoma S, Jiang T, Butterworth AS, Wood AM, Di Angelantonio E, Thompson JR, Danesh JN, Nelson CP, Samani NJ. Measurement and initial characterization of leukocyte telomere length in 474,074 participants in UK Biobank. Nat Aging 2022; 2:170-179. [PMID: 37117760 DOI: 10.1038/s43587-021-00166-9] [Citation(s) in RCA: 47] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Accepted: 12/21/2021] [Indexed: 04/30/2023]
Abstract
Leukocyte telomere length (LTL) is a proposed marker of biological age. Here we report the measurement and initial characterization of LTL in 474,074 participants in UK Biobank. We confirm that older age and male sex associate with shorter LTL, with women on average ~7 years younger in 'biological age' than men. Compared to white Europeans, LTL is markedly longer in African and Chinese ancestries. Older paternal age at birth is associated with longer individual LTL. Higher white cell count is associated with shorter LTL, but proportions of white cell subtypes show weaker associations. Age, ethnicity, sex and white cell count explain ~5.5% of LTL variance. Using paired samples from 1,351 participants taken ~5 years apart, we estimate the within-individual variability in LTL and provide a correction factor for this. This resource provides opportunities to investigate determinants and biomedical consequences of variation in LTL.
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Affiliation(s)
- V Codd
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK.
- NIHR Leicester Biomedical Research Centre, Glenfield Hospital, Leicester, UK.
| | - M Denniff
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - C Swinfield
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - S C Warner
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - M Papakonstantinou
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - S Sheth
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - D E Nanus
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - C A Budgeon
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
- NIHR Leicester Biomedical Research Centre, Glenfield Hospital, Leicester, UK
- School of Population and Global Health, University of Western Australia, Crawley, Western Australia, Australia
| | - C Musicha
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
- NIHR Leicester Biomedical Research Centre, Glenfield Hospital, Leicester, UK
| | - V Bountziouka
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
- NIHR Leicester Biomedical Research Centre, Glenfield Hospital, Leicester, UK
| | - Q Wang
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
- NIHR Leicester Biomedical Research Centre, Glenfield Hospital, Leicester, UK
| | - R Bramley
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
- NIHR Leicester Biomedical Research Centre, Glenfield Hospital, Leicester, UK
| | - E Allara
- British Heart Foundation Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
- National Institute for Health Research Blood and Transplant Research Unit in Donor Health and Genomics, University of Cambridge, Cambridge, UK
| | - S Kaptoge
- British Heart Foundation Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
- National Institute for Health Research Blood and Transplant Research Unit in Donor Health and Genomics, University of Cambridge, Cambridge, UK
- British Heart Foundation Centre of Research Excellence, University of Cambridge, Cambridge, UK
| | - S Stoma
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - T Jiang
- British Heart Foundation Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
| | - A S Butterworth
- British Heart Foundation Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
- National Institute for Health Research Blood and Transplant Research Unit in Donor Health and Genomics, University of Cambridge, Cambridge, UK
- British Heart Foundation Centre of Research Excellence, University of Cambridge, Cambridge, UK
- Health Data Research UK Cambridge, Wellcome Genome Campus and University of Cambridge, Cambridge, UK
| | - A M Wood
- British Heart Foundation Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
- National Institute for Health Research Blood and Transplant Research Unit in Donor Health and Genomics, University of Cambridge, Cambridge, UK
- British Heart Foundation Centre of Research Excellence, University of Cambridge, Cambridge, UK
- Health Data Research UK Cambridge, Wellcome Genome Campus and University of Cambridge, Cambridge, UK
- Medical Research Council Biostatistics Unit, Cambridge Institute of Public Health, University of Cambridge, Cambridge, UK
- The Alan Turing Institute, London, UK
| | - E Di Angelantonio
- British Heart Foundation Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
- National Institute for Health Research Blood and Transplant Research Unit in Donor Health and Genomics, University of Cambridge, Cambridge, UK
- British Heart Foundation Centre of Research Excellence, University of Cambridge, Cambridge, UK
- Health Data Research UK Cambridge, Wellcome Genome Campus and University of Cambridge, Cambridge, UK
- Health Data Science Centre, Human Technopole, Milan, Italy
| | - J R Thompson
- Department of Health Sciences, University of Leicester, Leicester, UK
| | - J N Danesh
- British Heart Foundation Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
- National Institute for Health Research Blood and Transplant Research Unit in Donor Health and Genomics, University of Cambridge, Cambridge, UK
- British Heart Foundation Centre of Research Excellence, University of Cambridge, Cambridge, UK
- Health Data Research UK Cambridge, Wellcome Genome Campus and University of Cambridge, Cambridge, UK
- Department of Human Genetics, Wellcome Sanger Institute, Hinxton, UK
| | - C P Nelson
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
- NIHR Leicester Biomedical Research Centre, Glenfield Hospital, Leicester, UK
| | - N J Samani
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK.
- NIHR Leicester Biomedical Research Centre, Glenfield Hospital, Leicester, UK.
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3
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Nelson CP, Lee RS, Trout AT, Servaes S, Kraft KH, Barnewolt CE, Logvinenko T, Chow JS. The association of postnatal urinary tract dilation risk score with clinical outcomes. J Pediatr Urol 2019; 15:341.e1-341.e6. [PMID: 31164273 DOI: 10.1016/j.jpurol.2019.05.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [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: 01/04/2019] [Accepted: 05/01/2019] [Indexed: 10/26/2022]
Abstract
BACKGROUND There are limited data on the predictive value of the consensus urinary tract dilation (UTD) score with respect to subsequent clinical diagnoses. We sought to define the relationship between postnatal UTD risk score and clinical outcomes during childhood. METHODS Complete ultrasound image sets from a random selection of infants aged 0-90 days undergoing initial ultrasound at a single institution for prenatal hydronephrosis between 2012 and 2014 were assigned a UTD score by 1 pediatric urologist and 1 pediatric radiologist. Urinary tract dilation risk score was analyzed for association with a composite outcome comprising urinary tract infection, vesicoureteral reflux (VUR), ureteropelvic junction obstruction, non-refluxing megaureter (NRM), ureterocele, bladder outlet obstruction (BOO), and chronic kidney disease. Surgical intervention and resolution of UTD were evaluated separately. Descriptive and survival analyses were performed. RESULTS Urinary tract dilation scores for 494 subjects were P0 in 23.5%, P1 in 26.5%, P2 in 23.5%, and P3 in 26.5%. Seventy-four percent were male. Median age at initial imaging was 28 days; median follow-up was 19.8 months. The composite outcome occurred in 138 of 494 patients (27.9%) and varied significantly (p < 0.001) by UTD score: 11.2% for P0, 10.7% for P1, 29.3% for P2, and 58.8% for P3. On survival analysis (Summary Figure), higher UTD grade was significantly associated with the composite outcome (hazard ratio for P3 vs. P0 was 7.4 [95% CI: 3.44-15.92, p < 0.001]). Urinary tract infection and VUR diagnosis varied by UTD score (p = 0.03 and p < 0.001, respectively). Ureteropelvic junction obstruction was diagnosed (based on MAG3 results) in 6.3% of patients, 84% of whom were P3. Non-refluxing megaureter was diagnosed in 7.7%. Ureterocele and BOO were uncommon (1.4%, and 0.6%, respectively). Surgical intervention was also associated with UTD risk, with 46% of P3 undergoing surgery vs. 1% of P0, 1% of P1, and 6% of P2 (p < 0.001). Resolution of UTD occurred in 41% (median 10.1 months) and varied significantly by UTD risk (p < 0.001). DISCUSSION Urinary tract dilation risk score is associated with clinical events, although ascertainment bias may influence some of the differences in outcomes, particularly for VUR, because VCUG utilization varied by the UTD group. The lack of any significant difference in outcomes between patients with UTD P0 versus P1 suggests that the P1 category could be eliminated as it does not meaningfully distinguish between outcome risk. CONCLUSIONS Higher UTD risk scores are strongly associated with genitourinary diagnoses during the first two years of life.
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Affiliation(s)
- C P Nelson
- Department of Urology, Boston Children's Hospital and Harvard Medical School, Boston MA, USA.
| | - R S Lee
- Department of Urology, Boston Children's Hospital and Harvard Medical School, Boston MA, USA
| | - A T Trout
- Department of Radiology, Cincinnati Children's Hospital Medical Center and Department of Radiology, University of Cincinnati Medical Center, Cincinnati OH, USA
| | - S Servaes
- Department of Radiology, Children's Hospital of Philadelphia, Philadelphia PA, USA
| | - K H Kraft
- Department of Urology, CS Mott Children's Hospital, University of Michigan, Ann Arbor MI, USA
| | - C E Barnewolt
- Department of Radiology, Boston Children's Hospital and Harvard Medical School, Boston MA, USA
| | - T Logvinenko
- Department of Urology, Boston Children's Hospital and Harvard Medical School, Boston MA, USA
| | - J S Chow
- Department of Radiology, Boston Children's Hospital and Harvard Medical School, Boston MA, USA
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Varda BK, Finkelstein JB, Wang HH, Logvinenko T, Nelson CP. The association between continuous antibiotic prophylaxis and UTI from birth until initial postnatal imaging evaluation among newborns with antenatal hydronephrosis. J Pediatr Urol 2018; 14:539.e1-539.e6. [PMID: 29891187 PMCID: PMC6265114 DOI: 10.1016/j.jpurol.2018.04.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [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: 12/08/2017] [Accepted: 04/15/2018] [Indexed: 10/16/2022]
Abstract
INTRODUCTION There is a lack of consensus regarding the use of continuous antibiotic prophylaxis (CAP) during the interval between birth and initial postnatal imaging in infants with a history of antenatal urinary tract dilation (AUTD). OBJECTIVE To determine the incidence of urinary tract infection (UTI), and the association between CAP use and UTI during the interval between birth and the first postnatal renal ultrasound (RUS) in infants with AUTD. STUDY DESIGN A single-institution, retrospective cohort study of newborns with a history of AUTD. Infants undergoing RUS within 3 months of birth for an indication of 'hydronephrosis' between 2012 and 2014 were identified. A random sample of 500 infants was selected; six were excluded for concomitant congenital anomalies. Baseline patient (sex, race, insurance) and clinical characteristics (circumcision status, UTD risk score, receipt of CAP, UTI prior to RUS, age at UTI, and age at RUS) were collected via retrospective chart review. Descriptive statistics were calculated. To adjust for receipt of CAP, propensity score adjusted univariate logistic regression for UTI based on CAP status was performed. RESULTS Among the 494 infants with AUTD, 157 (32%) received CAP. Infants with normal/low-risk UTD scores were less likely to receive CAP than those with medium/high-risk UTD (23% vs 77%; P < 0.001). There was no difference in CAP based on sex, insurance, or circumcision status (among 260/365 males with known circumcision status). Overall, seven infants (1.4%) developed UTI prior to imaging: six (1.8%) without CAP vs one (0.64%) with CAP (P = 0.44). The median age at UTI was 59 days (range 2-84); among those with UTI, initial imaging occurred significantly later (66 vs 28 days; P = 0.001). The propensity score adjusted odds of developing UTI with CAP (vs without) was 0.93 (95% CI 0.10-8.32; P = 0.95). The Summary Figure describes the infants with UTI. CONCLUSION The incidence of UTI prior to initial neonatal imaging in newborns with AUTD was low. Use of CAP was not associated with UTI incidence after adjusting for UTD severity. Routine use of CAP in newborns with AUTD prior to initial imaging may be of limited benefit in most patients.
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Affiliation(s)
- B K Varda
- Department of Urology, Boston Children's Hospital, Boston, MA, USA.
| | - J B Finkelstein
- Department of Urology, Boston Children's Hospital, Boston, MA, USA
| | - H-H Wang
- Department of Urology, Boston Children's Hospital, Boston, MA, USA
| | - T Logvinenko
- Department of Urology, Boston Children's Hospital, Boston, MA, USA
| | - C P Nelson
- Department of Urology, Boston Children's Hospital, Boston, MA, USA
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5
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Kurtz MP, MacDougall RD, Nelson CP. Urology mythbusters: Radiation and radiophobia. J Pediatr Urol 2018; 14:291-295. [PMID: 29571659 DOI: 10.1016/j.jpurol.2018.01.022] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Accepted: 01/29/2018] [Indexed: 11/16/2022]
Abstract
In this episode of Mythbusters we critically examine the premise that there is strong biological and epidemiologic evidence that radiation exposure at levels associated with modern genitourinary diagnostic imaging increases the risk of subsequent malignancy, especially in children.
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Affiliation(s)
- M P Kurtz
- Department of Urology, Boston Children's Hospital, Boston, MA, USA.
| | - R D MacDougall
- Department of Radiology, Boston Children's Hospital, Boston, MA, USA
| | - C P Nelson
- Department of Urology, Boston Children's Hospital, Boston, MA, USA
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6
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Vyas FS, Nelson CP, Dickenson JM. Role of transglutaminase 2 in A 1 adenosine receptor- and β 2-adrenoceptor-mediated pharmacological pre- and post-conditioning against hypoxia-reoxygenation-induced cell death in H9c2 cells. Eur J Pharmacol 2017; 819:144-160. [PMID: 29208472 DOI: 10.1016/j.ejphar.2017.11.049] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 11/20/2017] [Accepted: 11/30/2017] [Indexed: 02/07/2023]
Abstract
Pharmacologically-induced pre- and post-conditioning represent attractive therapeutic strategies to reduce ischaemia/reperfusion injury during cardiac surgery and following myocardial infarction. We have previously reported that transglutaminase 2 (TG2) activity is modulated by the A1 adenosine receptor and β2-adrenoceptor in H9c2 cardiomyoblasts. The primary aim of this study was to determine the role of TG2 in A1 adenosine receptor and β2-adrenoceptor-induced pharmacological pre- and post-conditioning in the H9c2 cells. H9c2 cells were exposed to 8h hypoxia (1% O2) followed by 18h reoxygenation, after which cell viability was assessed by monitoring mitochondrial reduction of MTT, lactate dehydrogenase release and caspase-3 activation. N6-cyclopentyladenosine (CPA; A1 adenosine receptor agonist), formoterol (β2-adrenoceptor agonist) or isoprenaline (non-selective β-adrenoceptor agonist) were added before hypoxia/reoxygenation (pre-conditioning) or at the start of reoxygenation following hypoxia (post-conditioning). Pharmacological pre- and post-conditioning with CPA and isoprenaline significantly reduced hypoxia/reoxygenation-induced cell death. In contrast, formoterol did not elicit protection. Pre-treatment with pertussis toxin (Gi/o-protein inhibitor), DPCPX (A1 adenosine receptor antagonist) or TG2 inhibitors (Z-DON and R283) attenuated the A1 adenosine receptor-induced pharmacological pre- and post-conditioning. Similarly, pertussis toxin, ICI 118,551 (β2-adrenoceptor antagonist) or TG2 inhibition attenuated the isoprenaline-induced cell survival. Knockdown of TG2 using small interfering RNA (siRNA) attenuated CPA and isoprenaline-induced pharmacological pre- and post-conditioning. Finally, proteomic analysis following isoprenaline treatment identified known (e.g. protein S100-A6) and novel (e.g. adenine phosphoribosyltransferase) protein substrates for TG2. These results have shown that A1 adenosine receptor and β2-adrenoceptor-induced protection against simulated hypoxia/reoxygenation occurs in a TG2 and Gi/o-protein dependent manner in H9c2 cardiomyoblasts.
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Affiliation(s)
- Falguni S Vyas
- School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS, UK
| | - Carl P Nelson
- School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS, UK
| | - John M Dickenson
- School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS, UK.
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7
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Miller S, Henry AP, Hodge E, Kheirallah AK, Billington CK, Rimington TL, Bhaker SK, Obeidat M, Melén E, Merid SK, Swan C, Gowland C, Nelson CP, Stewart CE, Bolton CE, Kilty I, Malarstig A, Parker SG, Moffatt MF, Wardlaw AJ, Hall IP, Sayers I. The Ser82 RAGE Variant Affects Lung Function and Serum RAGE in Smokers and sRAGE Production In Vitro. PLoS One 2016; 11:e0164041. [PMID: 27755550 PMCID: PMC5068780 DOI: 10.1371/journal.pone.0164041] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 09/19/2016] [Indexed: 12/30/2022] Open
Abstract
INTRODUCTION Genome-Wide Association Studies have identified associations between lung function measures and Chronic Obstructive Pulmonary Disease (COPD) and chromosome region 6p21 containing the gene for the Advanced Glycation End Product Receptor (AGER, encoding RAGE). We aimed to (i) characterise RAGE expression in the lung, (ii) identify AGER transcripts, (iii) ascertain if SNP rs2070600 (Gly82Ser C/T) is associated with lung function and serum sRAGE levels and (iv) identify whether the Gly82Ser variant is functionally important in altering sRAGE levels in an airway epithelial cell model. METHODS Immunohistochemistry was used to identify RAGE protein expression in 26 human tissues and qPCR was used to quantify AGER mRNA in lung cells. Gene expression array data was used to identify AGER expression during lung development in 38 fetal lung samples. RNA-Seq was used to identify AGER transcripts in lung cells. sRAGE levels were assessed in cells and patient serum by ELISA. BEAS2B-R1 cells were transfected to overexpress RAGE protein with either the Gly82 or Ser82 variant and sRAGE levels identified. RESULTS Immunohistochemical assessment of 6 adult lung samples identified high RAGE expression in the alveoli of healthy adults and individuals with COPD. AGER/RAGE expression increased across developmental stages in human fetal lung at both the mRNA (38 samples) and protein levels (20 samples). Extensive AGER splicing was identified. The rs2070600T (Ser82) allele is associated with higher FEV1, FEV1/FVC and lower serum sRAGE levels in UK smokers. Using an airway epithelium model overexpressing the Gly82 or Ser82 variants we found that HMGB1 activation of the RAGE-Ser82 receptor results in lower sRAGE production. CONCLUSIONS This study provides new information regarding the expression profile and potential role of RAGE in the human lung and shows a functional role of the Gly82Ser variant. These findings advance our understanding of the potential mechanisms underlying COPD particularly for carriers of this AGER polymorphism.
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Affiliation(s)
- Suzanne Miller
- Division of Respiratory Medicine, University of Nottingham, Nottingham, United Kingdom
- * E-mail:
| | - Amanda P. Henry
- Division of Respiratory Medicine, University of Nottingham, Nottingham, United Kingdom
| | - Emily Hodge
- Division of Respiratory Medicine, University of Nottingham, Nottingham, United Kingdom
| | | | | | - Tracy L. Rimington
- Division of Respiratory Medicine, University of Nottingham, Nottingham, United Kingdom
| | - Sangita K. Bhaker
- Division of Respiratory Medicine, University of Nottingham, Nottingham, United Kingdom
| | - Ma’en Obeidat
- Division of Respiratory Medicine, University of Nottingham, Nottingham, United Kingdom
| | - Erik Melén
- Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Simon K. Merid
- Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Caroline Swan
- Department of Biology, University of York, York, United Kingdom
| | - Catherine Gowland
- Division of Respiratory Medicine, University of Nottingham, Nottingham, United Kingdom
| | - Carl P. Nelson
- Division of Respiratory Medicine, University of Nottingham, Nottingham, United Kingdom
| | - Ceri E. Stewart
- Division of Respiratory Medicine, University of Nottingham, Nottingham, United Kingdom
| | - Charlotte E. Bolton
- Division of Respiratory Medicine, University of Nottingham, Nottingham, United Kingdom
| | - Iain Kilty
- Pfizer Worldwide Research & Development, Cambridge, Massachusetts, United States of America
| | - Anders Malarstig
- Pfizer Worldwide Research & Development, Cambridge, United Kingdom
| | - Stuart G. Parker
- Institute for Ageing and Health, Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne, United Kingdom
| | - Miriam F. Moffatt
- National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Andrew J. Wardlaw
- Institute for Lung Health, Immunity and Inflammation, University of Leicester, Leicester, United Kingdom
| | - Ian P. Hall
- Division of Respiratory Medicine, University of Nottingham, Nottingham, United Kingdom
| | - Ian Sayers
- Division of Respiratory Medicine, University of Nottingham, Nottingham, United Kingdom
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Musameh MD, Nelson CP, Gracey J, Tobin M, Tomaszewski M, Samani NJ. Determinants of day-night difference in blood pressure, a comparison with determinants of daytime and night-time blood pressure. J Hum Hypertens 2016; 31:43-48. [PMID: 26984683 PMCID: PMC5144126 DOI: 10.1038/jhh.2016.14] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [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] [Received: 08/29/2015] [Revised: 01/05/2016] [Accepted: 02/10/2016] [Indexed: 12/26/2022]
Abstract
Blunted day–night difference in blood pressure (BP) is an independent cardiovascular risk factor, although there is limited information on determinants of diurnal variation in BP. We investigated determinants of day–night difference in systolic (SBP) and diastolic (DBP) BP and how these compared with determinants of daytime and night-time SBP and DBP. We analysed the association of mean daytime, mean night-time and mean day–night difference (defined as (mean daytime−mean night-time)/mean daytime) in SBP and DBP with clinical, lifestyle and biochemical parameters from 1562 adult individuals (mean age 38.6) from 509 nuclear families recruited in the GRAPHIC Study. We estimated the heritability of the various BP phenotypes. In multivariate analysis, there were significant associations of age, sex, markers of adiposity (body mass index and waist–hip ratio), plasma lipids (total and low-density lipoprotein cholesterol and triglycerides), serum uric acid, alcohol intake and current smoking status on daytime or night-time SBP and/or DBP. Of these, only age (P=4.7 × 10−5), total cholesterol (P=0.002), plasma triglycerides (P=0.006) and current smoking (P=3.8 × 10−9) associated with day–night difference in SBP, and age (P=0.001), plasma triglyceride (P=2.2 × 10−5) and current smoking (3.8 × 10−4) associated with day–night difference in DBP. 24-h, daytime and night-time SBP and DBP showed substantial heritability (ranging from 18–43%). In contrast day–night difference in SBP showed a lower heritability (13%) while heritability of day–night difference in DBP was not significant. These data suggest that specific clinical, lifestyle and biochemical factors contribute to inter-individual variation in daytime, night-time and day–night differences in SBP and DBP. Variation in day–night differences in BP is largely non-genetic.
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Affiliation(s)
- M D Musameh
- Department of Cardiovascular Sciences, University of Leicester, British Heart Foundation Cardiovascular Research Centre, Glenfield Hospital, Leicester, UK.,National Institute for Health Research Leicester Cardiovascular Biomedical Research Unit, Glenfield Hospital, Leicester, UK
| | - C P Nelson
- Department of Cardiovascular Sciences, University of Leicester, British Heart Foundation Cardiovascular Research Centre, Glenfield Hospital, Leicester, UK.,National Institute for Health Research Leicester Cardiovascular Biomedical Research Unit, Glenfield Hospital, Leicester, UK
| | - J Gracey
- Department of Cardiovascular Sciences, University of Leicester, British Heart Foundation Cardiovascular Research Centre, Glenfield Hospital, Leicester, UK.,National Institute for Health Research Leicester Cardiovascular Biomedical Research Unit, Glenfield Hospital, Leicester, UK
| | - M Tobin
- Department of Health Sciences, University of Leicester, University Road, Leicester, UK
| | - M Tomaszewski
- Department of Cardiovascular Sciences, University of Leicester, British Heart Foundation Cardiovascular Research Centre, Glenfield Hospital, Leicester, UK.,National Institute for Health Research Leicester Cardiovascular Biomedical Research Unit, Glenfield Hospital, Leicester, UK
| | - N J Samani
- Department of Cardiovascular Sciences, University of Leicester, British Heart Foundation Cardiovascular Research Centre, Glenfield Hospital, Leicester, UK.,National Institute for Health Research Leicester Cardiovascular Biomedical Research Unit, Glenfield Hospital, Leicester, UK
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9
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Willets JM, Nash CA, Rainbow RD, Nelson CP, Challiss RAJ. Defining the roles of arrestin2 and arrestin3 in vasoconstrictor receptor desensitization in hypertension. Am J Physiol Cell Physiol 2015; 309:C179-89. [PMID: 25972452 PMCID: PMC4525080 DOI: 10.1152/ajpcell.00079.2015] [Citation(s) in RCA: 7] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Accepted: 05/11/2015] [Indexed: 11/22/2022]
Abstract
Prolonged vasoconstrictor-stimulated phospholipase C activity can induce arterial constriction, hypertension, and smooth muscle hypertrophy/hyperplasia. Arrestin proteins are recruited by agonist-occupied G protein-coupled receptors to terminate signaling and counteract changes in vascular tone. Here we determine whether the development of hypertension affects arrestin expression in resistance arteries and how such changes alter arterial contractile signaling and function. Arrestin2/3 expression was increased in mesenteric arteries of 12-wk-old spontaneously hypertensive rats (SHR) compared with normotensive Wistar-Kyoto (WKY) controls, while no differences in arrestin expression were observed between 6-wk-old SHR and WKY animals. In mesenteric artery myography experiments, high extracellular K(+)-stimulated contractions were increased in both 6- and 12-wk-old SHR animals. Concentration-response experiments for uridine 5'-triphosphate (UTP) acting through P2Y receptors displayed a leftward shift in 12-wk, but not 6-wk-old animals. Desensitization of UTP-stimulated vessel contractions was increased in 12-wk-old (but not 6-wk-old) SHR animals. Dual IP3/Ca(2+) imaging in mesenteric arterial cells showed that desensitization of UTP and endothelin-1 (ET1) responses was enhanced in 12-wk-old (but not 6-wk-old) SHR compared with WKY rats. siRNA-mediated depletion of arrestin2 for UTP and arrestin3 for ET1, reversed the desensitization of PLC signaling. In conclusion, arrestin2 and 3 expression is elevated in resistance arteries during the emergence of the early hypertensive phenotype, which underlies an enhanced ability to desensitize vasoconstrictor signaling and vessel contraction. Such regulatory changes may act to compensate for increased vasoconstrictor-induced vessel contraction.
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Affiliation(s)
- Jonathon M Willets
- Department of Cell Physiology and Pharmacology, University of Leicester, Leicester, United Kingdom; and
| | - Craig A Nash
- Department of Cell Physiology and Pharmacology, University of Leicester, Leicester, United Kingdom; and
| | - Richard D Rainbow
- Department of Cardiovascular Sciences, University of Leicester, Glenfield General Hospital, Leicester, United Kingdom
| | - Carl P Nelson
- Department of Cell Physiology and Pharmacology, University of Leicester, Leicester, United Kingdom; and
| | - R A John Challiss
- Department of Cell Physiology and Pharmacology, University of Leicester, Leicester, United Kingdom; and
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Obeidat M, Miller S, Probert K, Billington CK, Henry AP, Hodge E, Nelson CP, Stewart CE, Swan C, Wain LV, Artigas MS, Melén E, Ushey K, Hao K, Lamontagne M, Bossé Y, Postma DS, Tobin MD, Sayers I, Hall IP. GSTCD and INTS12 regulation and expression in the human lung. PLoS One 2013; 8:e74630. [PMID: 24058608 PMCID: PMC3776747 DOI: 10.1371/journal.pone.0074630] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Accepted: 08/05/2013] [Indexed: 12/29/2022] Open
Abstract
Genome-Wide Association Study (GWAS) meta-analyses have identified a strong association signal for lung function, which maps to a region on 4q24 containing two oppositely transcribed genes: glutathione S-transferase, C-terminal domain containing (GSTCD) and integrator complex subunit 12 (INTS12). Both genes were found to be expressed in a range of human airway cell types. The promoter regions and transcription start sites were determined in mRNA from human lung and a novel splice variant was identified for each gene. We obtained the following evidence for GSTCD and INTS12 co-regulation and expression: (i) correlated mRNA expression was observed both via Q-PCR and in a lung expression quantitative trait loci (eQTL) study, (ii) induction of both GSTCD and INTS12 mRNA expression in human airway smooth muscle cells was seen in response to TGFβ1, (iii) a lung eQTL study revealed that both GSTCD and INTS12 mRNA levels positively correlate with percent predicted FEV1, and (iv) FEV1 GWAS associated SNPs in 4q24 were found to act as an eQTL for INTS12 in a number of tissues. In fixed sections of human lung tissue, GSTCD protein expression was ubiquitous, whereas INTS12 expression was predominantly in epithelial cells and pneumocytes. During human fetal lung development, GSTCD protein expression was observed to be highest at the earlier pseudoglandular stage (10-12 weeks) compared with the later canalicular stage (17-19 weeks), whereas INTS12 expression levels did not alter throughout these stages. Knowledge of the transcriptional and translational regulation and expression of GSTCD and INTS12 provides important insights into the potential role of these genes in determining lung function. Future work is warranted to fully define the functions of INTS12 and GSTCD.
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Affiliation(s)
- Ma’en Obeidat
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Center, Nottingham, United Kingdom
- James Hogg Research Centre, Institute for Heart and Lung Health, University of British Columbia, Vancouver, British Columbia, Canada
| | - Suzanne Miller
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Center, Nottingham, United Kingdom
| | - Kelly Probert
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Center, Nottingham, United Kingdom
| | - Charlotte K. Billington
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Center, Nottingham, United Kingdom
| | - Amanda P. Henry
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Center, Nottingham, United Kingdom
| | - Emily Hodge
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Center, Nottingham, United Kingdom
| | - Carl P. Nelson
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Center, Nottingham, United Kingdom
| | - Ceri E. Stewart
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Center, Nottingham, United Kingdom
| | - Caroline Swan
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Center, Nottingham, United Kingdom
| | - Louise V. Wain
- Genetic Epidemiology Group, Department of Health Sciences, University of Leicester, Leicester, United Kingdom
| | - María Soler Artigas
- Genetic Epidemiology Group, Department of Health Sciences, University of Leicester, Leicester, United Kingdom
| | - Erik Melén
- Institute of Environmental Medicine, Karolinska Institutet and Sachs’ Children’s Hospital, Stockholm, Sweden
| | - Kevin Ushey
- James Hogg Research Centre, Institute for Heart and Lung Health, University of British Columbia, Vancouver, British Columbia, Canada
| | - Ke Hao
- Department of Genetics and Genomic Sciences, Icahn Institute of Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, United States of America
| | - Maxime Lamontagne
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Laval University, Québec City, Canada
| | - Yohan Bossé
- Department of Molecular Medicine, Laval University, Québec City, Canada
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Laval University, Québec City, Canada
| | - Dirkje S. Postma
- Department of Pulmonology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Martin D. Tobin
- Genetic Epidemiology Group, Department of Health Sciences, University of Leicester, Leicester, United Kingdom
- National Institute for Health Research (NIHR) Leicester Respiratory Biomedical Research Unit, Glenfield Hospital, Leicester, United Kingdom
| | - Ian Sayers
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Center, Nottingham, United Kingdom
| | - Ian P. Hall
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Center, Nottingham, United Kingdom
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Kokorowski PJ, Wang HHS, Routh JC, Hubert KC, Nelson CP. Evaluation of the contralateral inguinal ring in clinically unilateral inguinal hernia: a systematic review and meta-analysis. Hernia 2013; 18:311-24. [PMID: 23963735 DOI: 10.1007/s10029-013-1146-z] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2012] [Accepted: 07/28/2013] [Indexed: 11/25/2022]
Abstract
PURPOSE The management of the contralateral inguinal canal in children with clinical unilateral inguinal hernia is controversial. Our objective was to systematically review the literature regarding management of the contralateral inguinal canal. METHODS We searched MEDLINE, EMBASE, and Cochrane databases (1940-2011) using 'hernia' and 'inguinal' and either 'pediatric,' 'infant,' or 'child,' to identify studies of pediatric (age ≤21 years) patients with inguinal hernia. Among clinical unilateral hernia patients, we assessed the number of cases with contralateral patent processus (CPP) and incidence of subsequent clinical metachronous contralateral hernia (MCH). We evaluated three strategies for contralateral management: expectant management, laparoscopic evaluation or pre-operative ultrasound. Pooled estimates of MCH or CPP were generated with random effects by study when heterogeneity was found (I(2) > 50 %, or Cochrane's Q p ≥ 0.10). RESULTS We identified 2,477 non-duplicated studies, 129 of which met our inclusion criteria and had sufficient information for quantitative analysis. The pooled incidence of MCH after open unilateral repair was 7.3 % (95 % CI 6.5-8.1 %). Laparoscopic examination identified CPP in 30 % (95 % CI 26-34 %). Lower age was associated with higher incidence of CPP (p < 0.01). The incidence of MCH after a negative laparoscopic evaluation was 0.9 % (95 % CI 0.5-1.3 %). Significant heterogeneity was found in studies and pooled estimates should be interpreted with caution. CONCLUSIONS The literature suggests that laparoscopically identified CPP is a poor indicator of future contralateral hernia. Almost a third of patients will have a CPP, while less than one in 10 will develop MCH when managed expectantly. Performing contralateral hernia repair in patients with CPP results in overtreatment in roughly 2 out of 3 patients.
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Affiliation(s)
- P J Kokorowski
- Division of Urology, Children's Hospital Los Angeles, Institute of Urology, University of Southern California, 4650 Sunset Blvd., #114, Los Angeles, CA, 90027, USA,
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12
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Hodge E, Nelson CP, Miller S, Billington CK, Stewart CE, Swan C, Malarstig A, Henry AP, Gowland C, Melén E, Hall IP, Sayers I. HTR4 gene structure and altered expression in the developing lung. Respir Res 2013; 14:77. [PMID: 23890215 PMCID: PMC3750317 DOI: 10.1186/1465-9921-14-77] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [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: 06/13/2013] [Accepted: 07/23/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Meta-analyses of genome-wide association studies (GWAS) have identified single nucleotide polymorphisms (SNPs) spanning the 5-hydroxytryptamine receptor 4 (5-HT₄R) gene (HTR4) associated with lung function. The aims of this study were to i) investigate the expression profile of HTR4 in adult and fetal lung tissue and cultured airway cells, ii) further define HTR4 gene structure and iii) explore the potential functional implications of key SNPs using a bioinformatic approach. METHODS Following reverse transcription (RT)-PCR in human brain, 5' rapid amplification of cDNA ends (5' RACE) was used to examine the exonic structure of HTR4 at the 5' end. Quantitative (Q)-PCR was used to quantify HTR4 mRNA expression in total RNA from cultured airway cells and whole lung tissue. Publically available gene microarray data on fetal samples of estimated gestational age 7-22 weeks were mined for HTR4 expression. Immunohistochemistry (IHC; in adult and fetal lung tissue) and a radioligand binding assay (in cultured airway cells) were used to analyze 5-HT₄R protein expression. RESULTS IHC in adult lung, irrespective of the presence of chronic obstructive pulmonary disease (COPD), suggested low level expression of 5-HT₄R protein, which was most prominent in alveolar pneumocytes. There was evidence of differential 5-HT₄R protein levels during gestation in fetal lung, which was also evident in gene expression microarray data. HTR4 mRNA expression, assessed by Q-PCR, was <0.5% relative to brain in total adult lung tissue and in human airway smooth muscle (HASM) and bronchial epithelial cells (HBEC) derived from adult donors. Radioligand binding experiments also indicated that HBEC and HASM cells did not express a significant 5-HT₄R population. 5' RACE in brain identified a novel N-terminal variant, containing an extended N-terminal sequence. The functional significance of key HTR4 SNPs was investigated using the encyclopedia of DNA elements consortium (ENCODE) dataset. These analyses identified multiple alterations in regulatory motifs for transcription factors implicated in lung development, including Foxp1. CONCLUSIONS Taken together, these data suggest a role for HTR4 in lung development, which may at least in part explain the genetic association with lung function.
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Affiliation(s)
- Emily Hodge
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Centre, Nottingham NG7 2UH, UK
| | - Carl P Nelson
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Centre, Nottingham NG7 2UH, UK
| | - Suzanne Miller
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Centre, Nottingham NG7 2UH, UK
| | - Charlotte K Billington
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Centre, Nottingham NG7 2UH, UK
| | - Ceri E Stewart
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Centre, Nottingham NG7 2UH, UK
| | - Caroline Swan
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Centre, Nottingham NG7 2UH, UK
| | - Anders Malarstig
- Precision Medicine Unit, Pfizer Global Research and Development, Cambridge, UK
| | - Amanda P Henry
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Centre, Nottingham NG7 2UH, UK
| | - Catherine Gowland
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Centre, Nottingham NG7 2UH, UK
| | - Erik Melén
- Institute of Environmental Medicine, Karolinska Institutet and Sachs’ Children’s Hospital, Stockholm, Sweden
| | - Ian P Hall
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Centre, Nottingham NG7 2UH, UK
| | - Ian Sayers
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Centre, Nottingham NG7 2UH, UK
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Chan K, Patel RS, Newcombe P, Nelson CP, Qasim A, Epstein SE, Burnett S, Vaccarino VL, Zafari AM, Shah SH, Anderson JL, Carlquist JF, Hartiala J, Allayee H, Hinohara K, Lee BS, Erl A, Ellis KL, Goel A, Schaefer AS, Mokhtari NE, Goldstein BA, Hlatky MA, Go AS, Shen GQ, Gong Y, Pepine C, Laxton RC, Wittaker JC, Tang WHW, Johnson JA, Wang QK, Assimes TL, Nöthlings U, Farrall M, Watkins H, Richards AM, Cameron VA, Muendlein A, Drexel H, Koch W, Park JE, Kimura A, Shen WF, Simpson IA, Hazen SL, Horne BD, Hauser ER, Quyyumi AA, Reilly MP, Samani NJ, Ye S. 126 CHROMOSOME 9P21 LOCUS AND ANGIOGRAPHIC CORONARY ARTERY DISEASE BURDEN: A COLLABORATIVE META-ANALYSIS. Heart 2013. [DOI: 10.1136/heartjnl-2013-304019.126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Abstract
Inositol 1,4,5-trisphosphate (IP(3)) is a ubiquitous second messenger, derived from the hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP(2)) by enzymes of the phospholipase C (PLC) family. Binding of IP(3) to its cognate receptor in the endoplasmic reticulum membrane leads to release of Ca(2+) into the cytoplasm, which is involved in the regulation of an array of cellular functions. Traditional techniques for the detection of IP(3) have required the extraction of a large number of cells, with limitations in the time resolution of changes in IP(3) and an inability to obtain detailed information on the dynamics of this second messenger in single cells. Recent progress in this field has led to the development of a number of genetically encoded fluorescent biosensors, which upon recombinant expression are able selectively to detect real-time changes in IP(3) in single live cells. In this chapter, I detail protocols for the expression, visualization (by confocol or fluorescence microscopy), and interpretation of data obtained with such biosensors expressed in mammalian cells.
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Affiliation(s)
- Carl P Nelson
- Department of Cardiovascular Sciences, Division of Anaesthesia, Critical Care, and Pain Management, Leicester Royal Infirmary, University of Leicester, Leicester, UK.
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15
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Abstract
BACKGROUND Under certain assumptions, relative survival is a measure of net survival based on estimating the excess mortality in a study population when compared with the general population. Background mortality estimates are usually taken from national life tables that are broken down by age, sex and calendar year. A fundamental assumption of relative survival methods is that if a patient did not have the disease of interest then their probability of survival would be comparable to that of the general population. It is argued, as most lung cancer patients are smokers and therefore carry a higher risk of smoking-related mortalities, that they are not comparable to a population where the majority are likely to be non-smokers. METHODS We use data from the Finnish Cancer Registry to assess the impact that the non-comparability assumption has on the estimates of relative survival through the use of a sensitivity analysis. RESULTS Under realistic estimates of increased all-cause mortality for smokers compared with non-smokers, the bias in the estimates of relative survival caused by the non-comparability assumption is negligible. CONCLUSION Although the assumption of comparability underlying the relative survival method may not be reasonable, it does not have a concerning impact on the estimates of relative survival, as most lung cancer patients die within the first 2 years following diagnosis. This should serve to reassure critics of the use of relative survival when applied to lung cancer data.
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Affiliation(s)
- S R Hinchliffe
- Department of Health Sciences, Centre for Biostatistics and Genetic Epidemiology, 2nd Floor Adrian Building, University Road, University of Leicester, Leicester LE1 7RH, UK.
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Morris GE, Nelson CP, Brighton PJ, Standen NB, Challiss RAJ, Willets JM. Arrestins 2 and 3 differentially regulate ETA and P2Y2 receptor-mediated cell signaling and migration in arterial smooth muscle. Am J Physiol Cell Physiol 2011; 302:C723-34. [PMID: 22159081 DOI: 10.1152/ajpcell.00202.2011] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Overstimulation of endothelin type A (ET(A)) and nucleotide (P2Y) Gα(q)-coupled receptors in vascular smooth muscle causes vasoconstriction, hypertension, and, eventually, hypertrophy and vascular occlusion. G protein-coupled receptor kinases (GRKs) and arrestin proteins are sequentially recruited by agonist-occupied Gα(q)-coupled receptors to terminate phospholipase C signaling, preventing prolonged/inappropriate contractile signaling. However, these proteins also play roles in the regulation of several mitogen-activated protein kinase (MAPK) signaling cascades known to be essential for vascular remodeling. Here we investigated whether different arrestin isoforms regulate endothelin and nucleotide receptor MAPK signaling in rat aortic smooth muscle cells (ASMCs). When intracellular Ca(2+) levels were assessed in isolated ASMCs loaded with Ca(2+)-sensitive dyes, P2Y(2) and ET(A) receptor desensitization was attenuated by selective small-interfering (si)RNA-mediated depletion of G protein-coupled receptor kinase 2 (GRK2). Using similar siRNA techniques, knockdown of arrestin2 prevented P2Y(2) receptor desensitization and enhanced and prolonged p38 and ERK MAPK signals, while arrestin3 depletion was ineffective. Conversely, arrestin3 knockdown prevented ET(A) receptor desensitization and attenuated ET1-stimulated p38 and ERK signals, while arrestin2 depletion had no effect. Using Transwell assays to assess agonist-stimulated ASMC migration, we found that UTP-stimulated migration was markedly attenuated following arrestin2 depletion, while ET1-stimulated migration was attenuated following knockdown of either arrestin. These data highlight a differential arrestin-dependent regulation of ET(A) and P2Y(2) receptor-stimulated MAPK signaling. GRK2 and arrestin expression are essential for agonist-stimulated ASMC migration, which, as a key process in vascular remodeling, highlights the potential roles of GRK2 and arrestin proteins in the progression of vascular disease.
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Affiliation(s)
- Gavin E Morris
- Dept. of Cancer Studies and Molecular Medicine, Leicester Royal Infirmary, Leicester, UK
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Nelson CP, Rainbow RD, Brignell JL, Perry MD, Willets JM, Davies NW, Standen NB, Challiss RJ. Principal role of adenylyl cyclase 6 in K⁺ channel regulation and vasodilator signalling in vascular smooth muscle cells. Cardiovasc Res 2011; 91:694-702. [PMID: 21606183 PMCID: PMC3156907 DOI: 10.1093/cvr/cvr137] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2011] [Revised: 05/06/2011] [Accepted: 05/12/2011] [Indexed: 02/07/2023] Open
Abstract
AIMS Membrane potential is a key determinant of vascular tone and many vasodilators act through the modulation of ion channel currents [e.g. the ATP-sensitive potassium channel (K(ATP))] involved in setting the membrane potential. Adenylyl cyclase (AC) isoenzymes are potentially important intermediaries in such vasodilator signalling pathways. Vascular smooth muscle cells (VSMCs) express multiple AC isoenzymes, but the reason for such redundancy is unknown. We investigated which of these isoenzymes are involved in vasodilator signalling and regulation of vascular ion channels important in modulating membrane potential. METHODS AND RESULTS AC isoenzymes were selectively depleted (by >75%) by transfection of cultured VSMCs with selective short interfering RNA sequences. AC6 was the predominant isoenzyme involved in vasodilator-mediated cAMP accumulation in VSMCs, accounting for ∼60% of the total response to β-adrenoceptor (β-AR) stimulation. AC3 played a minor role in β-AR signalling, whereas AC5 made no significant contribution. AC6 was also the principal isoenzyme involved in β-AR-mediated protein kinase A (PKA) signalling (determined using the fluorescent biosensor for PKA activity, AKAR3) and the substantial β-AR/PKA-dependent enhancement of K(ATP) current. K(ATP) current was shown to play a vital role in setting the resting membrane potential and in mediating the hyperpolarization observed upon β-AR stimulation. CONCLUSION AC6, but not the closely related AC5, plays a principal role in vasodilator signalling and regulation of the membrane potential in VSMCs. These findings identify AC6 as a vital component in the vasodilatory apparatus central to the control of blood pressure.
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Affiliation(s)
- Carl P. Nelson
- Department of Cell Physiology and Pharmacology, University of Leicester, Henry Wellcome Building, Lancaster Road, Leicester LE1 9HN, UK
| | - Richard D. Rainbow
- Department of Cardiovascular Sciences, University of Leicester, Robert Kilpatrick Clinical Sciences Building, Leicester Royal Infirmary, Leicester LE2 7LX, UK
| | - Jennifer L. Brignell
- Department of Cell Physiology and Pharmacology, University of Leicester, Henry Wellcome Building, Lancaster Road, Leicester LE1 9HN, UK
| | - Matthew D. Perry
- Department of Cell Physiology and Pharmacology, University of Leicester, Henry Wellcome Building, Lancaster Road, Leicester LE1 9HN, UK
| | - Jonathon M. Willets
- Department of Cell Physiology and Pharmacology, University of Leicester, Henry Wellcome Building, Lancaster Road, Leicester LE1 9HN, UK
- Department of Cancer Studies and Molecular Medicine, University of Leicester, Robert Kilpatrick Clinical Sciences Building, Leicester Royal Infirmary, Leicester LE2 7LX, UK
| | - Noel W. Davies
- Department of Cell Physiology and Pharmacology, University of Leicester, Henry Wellcome Building, Lancaster Road, Leicester LE1 9HN, UK
| | - Nicholas B. Standen
- Department of Cell Physiology and Pharmacology, University of Leicester, Henry Wellcome Building, Lancaster Road, Leicester LE1 9HN, UK
| | - R.A. John Challiss
- Department of Cell Physiology and Pharmacology, University of Leicester, Henry Wellcome Building, Lancaster Road, Leicester LE1 9HN, UK
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Abstract
The ability to visualize the subcellular localization of proteins by labeling them with fluorescent proteins is a powerful tool in cell biology. In the G protein-coupled receptor signaling field, this technique has been utilized to examine the various aspects of receptor behavior, including activation, internalization and recycling, as well as alterations in the cellular levels of a variety of second messengers and signaling intermediates. Attaching variants of green fluorescent protein on to protein modules, which possess high affinity and selectivity for specific signaling molecules has allowed the visualization of key signaling pathway intermediates in real time, in living cells. This chapter outlines a protocol for the expression and visualization (by confocal microscopy) of such fluorescent "biosensors" and provides guidance on the analysis and interpretation of data obtained from such experiments.
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Affiliation(s)
- Carl P Nelson
- Department of Cell Physiology and Pharmacology, University of Leicester, Leicester, UK
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19
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Morris GE, Nelson CP, Everitt D, Brighton PJ, Standen NB, Challiss RAJ, Willets JM. G protein-coupled receptor kinase 2 and arrestin2 regulate arterial smooth muscle P2Y-purinoceptor signalling. Cardiovasc Res 2010; 89:193-203. [PMID: 20705669 PMCID: PMC3002865 DOI: 10.1093/cvr/cvq249] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
AIMS prolonged P2Y-receptor signalling can cause vasoconstriction leading to hypertension, vascular smooth muscle hypertrophy, and hyperplasia. G protein-coupled receptor signalling is negatively regulated by G protein-coupled receptor kinases (GRKs) and arrestin proteins, preventing prolonged or inappropriate signalling. This study investigates whether GRKs and arrestins regulate uridine 5'-triphosphate (UTP)-stimulated contractile signalling in adult Wistar rat mesenteric arterial smooth muscle cells (MSMCs). METHODS AND RESULTS mesenteric arteries contracted in response to UTP challenge: When an EC(50) UTP concentration (30 µM, 5 min) was added 5 min before (R(1)) and after (R(2)) the addition of a maximal UTP concentration (R(max): 100 µM, 5 min), R(2) responses were decreased relative to R(1), indicating desensitization. UTP-induced P2Y-receptor desensitization of phospholipase C signalling was studied in isolated MSMCs transfected with an inositol 1,4,5-trisphosphate biosensor and/or loaded with Ca(2+)-sensitive dyes. A similar protocol (R(1)/R(2) = 10 µM; R(max) = 100 µM, applied for 30 s) revealed markedly reduced R(2) when compared with R(1) responses. MSMCs were transfected with dominant-negative GRKs or siRNAs targeting specific GRK/arrestins to probe their respective roles in P2Y-receptor desensitization. GRK2 inhibition, but not GRK3, GRK5, or GRK6, attenuated P2Y-receptor desensitization. siRNA-mediated knockdown of arrestin2 attenuated UTP-stimulated P2Y-receptor desensitization, whereas arrestin3 depletion did not. Specific siRNA knockdown of the P2Y(2)-receptor almost completely abolished UTP-stimulated IP(3)/Ca(2+) signalling, strongly suggesting that our study is specifically characterizing this purinoceptor subtype. CONCLUSION these new data highlight roles of GRK2 and arrestin2 as important regulators of UTP-stimulated P2Y(2)-receptor responsiveness in resistance arteries, emphasizing their potential importance in regulating vasoconstrictor signalling pathways implicated in vascular disease.
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Affiliation(s)
- Gavin E Morris
- Reproductive Sciences Section, Department of Cancer Studies and Molecular Medicine, Clinical Sciences Building, Leicester Royal Infirmary, Leicester LE2 7LX, UK
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Lambert PC, Dickman PW, Nelson CP, Royston P. Estimating the crude probability of death due to cancer and other causes using relative survival models. Stat Med 2010; 29:885-95. [PMID: 20213719 DOI: 10.1002/sim.3762] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Relative survival is used extensively in population-based cancer studies to measure patient survival correcting for causes of death not related to the disease of interest. An advantage of relative survival is that it provides a measure of mortality associated with a particular disease, without the need for information on cause of death. Relative survival provides a measure of net mortality, i.e. the probability of death due to cancer in the absence of other causes. This is a useful measure, but it is also of interest to measure crude mortality, i.e. the probability of death due to cancer in the presence of other causes. A previous approach to estimate the crude probability of death in population-based cancer studies used life table methods, but we show how the estimates can be obtained after fitting a relative survival model. We adopt flexible parametric models for relative survival, which use restricted cubic splines for the baseline cumulative excess hazard and for any time-dependent effects. We illustrate the approach using an example of men diagnosed with prostate cancer in England and Wales showing the differences in net and crude survival for different ages.
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Affiliation(s)
- P C Lambert
- Department of Health Sciences, Centre for Biostatistics and Genetic Epidemiology, University of Leicester, 2nd Floor, Adrian Building, University Road, Leicester LE1 7RH, U.K.
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Morris GE, Nelson CP, Standen NB, Challiss RAJ, Willets JM. Endothelin signalling in arterial smooth muscle is tightly regulated by G protein-coupled receptor kinase 2. Cardiovasc Res 2009; 85:424-33. [PMID: 19748906 PMCID: PMC2802200 DOI: 10.1093/cvr/cvp310] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
AIMS Prolonged endothelin (ET) receptor signalling causes vasoconstriction and can lead to hypertension, vascular smooth muscle hypertrophy, and hyperplasia. Usually, G protein-coupled receptor signalling is negatively regulated by G protein-coupled receptor kinases (GRKs), preventing prolonged or inappropriate signalling. This study investigated whether GRKs regulate ET receptor contractile signalling in adult Wistar rat mesenteric arterial smooth muscle cells (MSMCs). METHODS AND RESULTS ET-1-stimulated phospholipase C (PLC) activity and changes in [Ca2+]i were assessed using confocal microscopy in rat MSMCs transfected with the pleckstrin-homology domain of PLCdelta1 (eGFP-PH) and loaded with Fura-Red. ET-1 applications (30 s) stimulated transient concentration-dependent eGFP-PH translocations from plasma membrane to cytoplasm and graded [Ca2+]i increases. ET-1-mediated PLC signalling was blocked by the type A endothelin receptor (ET(A)R) antagonist, BQ123. To characterize ET(A)R desensitization, cells were stimulated with a maximally effective concentration of ET-1 (50 nM, 30 s) followed by a variable washout period and a second identical application of ET-1. This brief exposure to ET-1 markedly decreased ET(A)R responsiveness to re-challenge, and reversal was incomplete even after increasing the time period between agonist challenges to 60 min. To assess GRK involvement in ET(A)R desensitization, MSMCs were co-transfected with eGFP-PH and catalytically inactive (D110A,K220R)GRK2, (D110A,K220R)GRK3, (K215R)GRK5, or (K215R)GRK6 constructs. (D110A,K220R)GRK2 expression significantly attenuated ET(A)R desensitization, whereas other constructs were ineffective. Small interfering RNA-targeted GRK2 depletion equally attenuated ET(A)R desensitization. Finally, immunocyotchemical data showed that ET(A)R activation recruited endogenous GRK2 from cytoplasm to membrane. CONCLUSION These studies identify GRK2 as a key regulator of ET(A)R responsiveness in resistance arteries, highlighting the potential importance of this GRK isoenzyme in regulating vasoconstrictor signalling pathways implicated in vascular disease.
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Affiliation(s)
- Gavin E Morris
- Reproductive Sciences Section, Department of Cancer Studies and Molecular Medicine, Clinical Sciences Building, Leicester Royal Infirmary, Leicester LE2 7LX, UK
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Nelson CP, Willets JM, Davies NW, Challiss RAJ, Standen NB. Visualizing the temporal effects of vasoconstrictors on PKC translocation and Ca2+ signaling in single resistance arterial smooth muscle cells. Am J Physiol Cell Physiol 2008; 295:C1590-601. [PMID: 18829899 DOI: 10.1152/ajpcell.00365.2008] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Arterial smooth muscle (ASM) contraction plays a critical role in regulating blood distribution and blood pressure. Vasoconstrictors activate cell surface receptors to initiate signaling cascades involving increased intracellular Ca(2+) concentration ([Ca(2+)](i)) and recruitment of protein kinase C (PKC), leading to ASM contraction, though the PKC isoenzymes involved vary between different vasoconstrictors and their actions. Here, we have used confocal microscopy of enhanced green fluorescence protein (eGFP)-labeled PKC isoenzymes to visualize PKC translocation in primary rat mesenteric ASM cells in response to physiological vasoconstrictors, with simultaneous imaging of Ca(2+) signaling. Endothelin-1, angiotensin II, and uridine triphosphate all caused translocation of each of the PKC isoenzymes alpha, delta, and epsilon; however, the kinetics of translocation varied between agonists and PKC isoenzymes. Translocation of eGFP-PKCalpha mirrored the rise in [Ca(2+)](i), while that of eGFP-PKCdelta or -epsilon occurred more slowly. Endothelin-induced translocation of eGFP-PKCepsilon was often sustained for several minutes, while responses to angiotensin II were always transient. In addition, preventing [Ca(2+)](i) increases using 1,2-bis-(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid tetra-(acetoxymethyl) ester prevented eGFP-PKCalpha translocation, while eGFP-PKCdelta translocated more rapidly. Our results suggest that PKC isoenzyme specificity of vasoconstrictor actions occurs downstream of PKC recruitment and demonstrate the varied kinetics and complex interplay between Ca(2+) and PKC responses to different vasoconstrictors in ASM.
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Affiliation(s)
- Carl P Nelson
- Department of Cell Physiology & Pharmacology, Univ. of Leicester, LE1 9HN, UK.
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Nelson CP, Nahorski SR, Challiss RAJ. Temporal profiling of changes in phosphatidylinositol 4,5-bisphosphate, inositol 1,4,5-trisphosphate and diacylglycerol allows comprehensive analysis of phospholipase C-initiated signalling in single neurons. J Neurochem 2008; 107:602-15. [PMID: 18665913 PMCID: PMC2779467 DOI: 10.1111/j.1471-4159.2008.05587.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [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: 11/27/2022]
Abstract
Phosphatidylinositol 4,5-bisphosphate (PIP2) fulfils vital signalling roles in an array of cellular processes, yet until recently it has not been possible selectively to visualize real-time changes in PIP2 levels within living cells. Green fluorescent protein (GFP)-labelled Tubby protein (GFP-Tubby) enriches to the plasma membrane at rest and translocates to the cytosol following activation of endogenous Gαq/11-coupled muscarinic acetylcholine receptors in both SH-SY5Y human neuroblastoma cells and primary rat hippocampal neurons. GFP-Tubby translocation is independent of changes in cytosolic inositol 1,4,5-trisphosphate and instead reports dynamic changes in levels of plasma membrane PIP2. In contrast, enhanced GFP (eGFP)-tagged pleckstrin homology domain of phospholipase C (PLCδ1) (eGFP-PH) translocation reports increases in cytosolic inositol 1,4,5-trisphosphate. Comparison of GFP-Tubby, eGFP-PH and the eGFP-tagged C12 domain of protein kinase C-γ [eGFP-C1(2); to detect diacylglycerol] allowed a selective and comprehensive analysis of PLC-initiated signalling in living cells. Manipulating intracellular Ca2+ concentrations in the nanomolar range established that GFP-Tubby responses to a muscarinic agonist were sensitive to intracellular Ca2+ up to 100–200 nM in SH-SY5Y cells, demonstrating the exquisite sensitivity of agonist-mediated PLC activity within the range of physiological resting Ca2+ concentrations. We have also exploited GFP-Tubby selectively to visualize, for the first time, real-time changes in PIP2 in hippocampal neurons.
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Affiliation(s)
- Carl P Nelson
- Department of Cell Physiology & Pharmacology, University of Leicester, Leicester, UK
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Willets JM, Nelson CP, Nahorski SR, Challiss RAJ. The regulation of M1 muscarinic acetylcholine receptor desensitization by synaptic activity in cultured hippocampal neurons. J Neurochem 2007; 103:2268-80. [PMID: 17908240 PMCID: PMC2658029 DOI: 10.1111/j.1471-4159.2007.04931.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
To better understand metabotropic/ionotropic integration in neurons we have examined the regulation of M1 muscarinic acetylcholine (mACh) receptor signalling in mature (> 14 days in vitro), synaptically-active hippocampal neurons in culture. Using a protocol where neurons are exposed to an EC(50) concentration of the muscarinic agonist methacholine (MCh) prior to (R1), and following (R2) a desensitizing pulse of a high concentration of this agonist, we have found that the reduction in M(1) mACh receptor responsiveness is decreased in quiescent (+tetrodotoxin) neurons and increased when synaptic activity is enhanced by blocking GABA(A) receptors with picrotoxin. The picrotoxin-mediated effect on M1 mACh receptor responsiveness was completely prevented by alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor blockade. Inhibition of endogenous G protein-coupled receptor kinase 2 by transfection with the non-G(q/11)alpha-binding, catalytically-inactive (D110A,K220R)G protein-coupled receptor kinase 2 mutant, decreased the extent of M1 mACh receptor desensitization under all conditions. Pharmacological inhibition of protein kinase C (PKC) activity, or chronic phorbol ester-induced PKC down-regulation had no effect on agonist-mediated receptor desensitization in quiescent or spontaneously synaptically active neurons, but significantly decreased the extent of receptor desensitization in picrotoxin-treated neurons. MCh stimulated the translocation of diacylglycerol- sensitive eGFP-PKCepsilon, but not Ca2+/diacylglycerol-sensitive eGFP-PKCbetaII in both the absence, and presence of tetrodotoxin. Under these conditions, MCh-stimulated eGFP-myristoylated, alanine-rich C kinase substrate translocation was dependent on PKC activity, but not Ca2+/calmodulin. In contrast, picrotoxin-driven translocation of myristoylated, alanine-rich C kinase substrate was accompanied by translocation of PKCbetaII, but not PKCepsilon, and was dependent on PKC and Ca2+/calmodulin. Taken together these data suggest that the level of synaptic activity may determine the different kinases recruited to regulate M1 mACh receptor desensitization in neurons.
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Affiliation(s)
- Jonathon M Willets
- Department of Cell Physiology and Pharmacology, University of Leicester, Leicester, UK
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Abstract
OBJECTIVE Many changes have occurred in the treatment of bladder exstrophy over the last few years and many repairs are now offered. The purpose of this study was to evaluate long-term outcomes in a select group of patients in whom modern staged repair (MSRE) was undertaken. PATIENTS AND METHODS From an institutionally approved database were extracted 189 patients who had undergone primary closure between 1988 and 2004. The records of 131 patients (95 males) who underwent MSRE with a modified Cantwell-Ransley repair by a single surgeon in 1988-2004 were reviewed with a minimum 5-year follow up. RESULTS Sixty-seven patients with a mean age of 2 months (range 6 h to 4 months) underwent primary closure, and 18 underwent osteotomy at the same time. Mean age at epispadias repair was 18 months (8-24). Mean age at bladder neck reconstruction (BNR) was 4.8 years (40-60 months) with a mean capacity of 98 cc (75-185). Analysis of bladder capacity prior to BNR revealed that patients with a mean capacity greater than 85 cc median had better outcomes. Seventy percent (n=47) are continent day and night and voiding per urethra without augmentation or intermittent catheterization. Social continence defined as dry for more than 3h during the day was found in 10% (n=7). Six patients required continent diversion after failed BNR. Seven patients are completely incontinent. The mean time to daytime continence was 14 months (4-23) and the mean time to night-time continence was 23 months (11-34). No correlation was found between age at BNR and continence. CONCLUSIONS Patients with a good bladder template who develop sufficient bladder capacity after successful primary closure and epispadias repair can achieve acceptable continence without bladder augmentation and intermittent catheterization.
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Affiliation(s)
- A D Baird
- Division of Pediatric Urology, Brady Urological Institute, Marburg 146, The Johns Hopkins Hospital, 600 North Wolfe Street, Baltimore, MD 21287, USA.
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Nelson CP, Challiss RAJ. “Phenotypic” pharmacology: The influence of cellular environment on G protein-coupled receptor antagonist and inverse agonist pharmacology. Biochem Pharmacol 2007; 73:737-51. [PMID: 17046719 DOI: 10.1016/j.bcp.2006.09.005] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2006] [Revised: 08/31/2006] [Accepted: 09/06/2006] [Indexed: 11/25/2022]
Abstract
A central dogma of G protein-coupled receptor (GPCR) pharmacology has been the concept that unlike agonists, antagonist ligands display equivalent affinities for a given receptor, regardless of the cellular environment in which the affinity is assayed. Indeed, the widespread use of antagonist pharmacology in the classification of receptor expression profiles in vivo has relied upon this 'antagonist assumption'. However, emerging evidence suggests that the same gene-product may exhibit different antagonist pharmacological profiles, depending upon the cellular context in which it is expressed-so-called 'phenotypic' profiles. In this commentary, we review the evidence relating to some specific examples, focusing on adrenergic and muscarinic acetylcholine receptor systems, where GPCR antagonist/inverse agonist pharmacology has been demonstrated to be cell- or tissue-dependent, before going on to examine some of the ways in which the cellular environment might modulate receptor pharmacology. In the majority of cases, the cellular factors responsible for generating phenotypic profiles are unknown, but there is substantial evidence that factors, including post-transcriptional modifications, receptor oligomerization and constitutive receptor activity, can influence GPCR pharmacology and these concepts are discussed in relation to antagonist phenotypic profiles. A better molecular understanding of the impact of cell background on GPCR antagonist pharmacology is likely to provide previously unrealized opportunities to achieve greater specificity in new drug discovery candidates.
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Affiliation(s)
- Carl P Nelson
- Department of Cell Physiology & Pharmacology, University of Leicester, Henry Wellcome Building, Lancaster Road, Leicester LE1 9HN, UK.
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Young KW, Billups D, Nelson CP, Johnston N, Willets JM, Schell MJ, Challiss RAJ, Nahorski SR. Muscarinic acetylcholine receptor activation enhances hippocampal neuron excitability and potentiates synaptically evoked Ca(2+) signals via phosphatidylinositol 4,5-bisphosphate depletion. Mol Cell Neurosci 2005; 30:48-57. [PMID: 15996483 DOI: 10.1016/j.mcn.2005.05.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2005] [Revised: 05/18/2005] [Accepted: 05/24/2005] [Indexed: 11/20/2022] Open
Abstract
Using single cell Ca(2+) imaging and whole cell current clamp recordings, this study aimed to identify the signal transduction mechanisms involved in mACh receptor-mediated, enhanced synaptic signaling in primary cultures of hippocampal neurons. Activation of M(1) mACh receptors produced a 2.48 +/- 0.26-fold enhancement of Ca(2+) transients arising from spontaneous synaptic activity in hippocampal neurons. Combined imaging of spontaneous Ca(2+) signals with inositol 1,4,5-trisphosphate (IP(3)) production in single neurons demonstrated that the methacholine (MCh)-mediated enhancement required activated G(q/11)alpha subunits and phospholipase C activity but did not require measurable increases in IP(3). Electrophysiological studies demonstrated that MCh treatment depolarized neurons from -64 +/- 3 to -45 +/- 3 mV and increased action potential generation. Depletion of plasma membrane phosphatidylinositol 4,5-bisphosphate (PIP(2)) enhanced neuronal excitability and prolonged the action of MCh. These studies suggest that, in addition to producing the second messengers IP(3) and diacylglycerol, mACh receptor activation may directly utilize PIP(2) hydrolysis to regulate neuronal excitability.
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Affiliation(s)
- Kenneth W Young
- Department of Cell Physiology and Pharmacology, Medical Sciences Building, University of Leicester, University Road, Leicester, LE1 9HN, UK.
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Abstract
Introduction of a single-point mutation (Asn to Tyr) at position 410 at the junction between transmembrane domain 6 and the third extracellular loop of the human M(2) muscarinic acetylcholine (mACh) receptor generated a mutant receptor (N410Y) that possesses many of the hallmark features of a constitutively active mutant receptor. These included enhanced agonist binding affinity and potency, in addition to agonist-independent accumulation of [(3)H]inositol phosphates in cells coexpressing the chimeric Galpha(qi5) protein and the N410Y mutant M(2) mACh receptor. Constitutive activity was sensitive to inhibition by a range of muscarinic ligands, including those used clinically in the management of overactive bladder (oxybutynin, tolterodine, and darifenacin), indicating that these ligands behave as inverse agonists at the M(2) mACh receptor. Long-term (24-h) treatment of Chinese hamster ovary cells expressing the N410Y mutant M(2) mACh receptor with certain mACh receptor inverse agonists (atropine, darifenacin, and pirenzepine) elicited a concentration-dependent up-regulation of cell surface receptor expression. However, not all ligands possessing negative efficacy in the [(3)H]inositol phosphate accumulation assays were capable of significantly up-regulating receptor expression, perhaps indicating a spectrum of negative efficacies among ligands traditionally defined as mACh receptor antagonists. Finally, structurally distinct agonists exhibited differences in their relative potencies for the activation of Galpha(i/o) versus Galpha(s), consistent with agonist-directed trafficking of signaling at the N410Y mutant, but not at the wild-type M(2) mACh receptor. This indicates that the N410Y mutation of the M(2) mACh receptor alters receptor-G-protein coupling in an agonist-dependent manner, in addition to generating a constitutively active receptor phenotype.
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Affiliation(s)
- Carl P Nelson
- Department of Cell Physiology and Pharmacology, University of Leicester, University Road, Leicester LE1 9HN, UK
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Nelson CP, Gupta P, Napier CM, Nahorski SR, Challiss RAJ. Functional selectivity of muscarinic receptor antagonists for inhibition of M3-mediated phosphoinositide responses in guinea pig urinary bladder and submandibular salivary gland. J Pharmacol Exp Ther 2004; 310:1255-65. [PMID: 15140916 DOI: 10.1124/jpet.104.067140] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Binding and functional affinities of the muscarinic acetylcholine (mACh) receptor antagonists darifenacin, tolterodine, oxybutynin, and atropine were assessed in Chinese hamster ovary (CHO) cells expressing the human recombinant M2 (CHO-m2) or M3 (CHO-m3) receptors, and in guinea pig bladder and submandibular gland. In [N-methyl-3H]scopolamine methyl chloride binding studies in CHO cells, darifenacin displayed selectivity (14.8-fold) for the M3 versus M2 mACh receptor subtype. Oxybutynin was nonselective, whereas atropine and tolterodine were weakly M2-selective (5.1- and 6.6-fold, respectively). Antagonist functional affinity estimates were determined by the inhibition of agonist-induced [3H]inositol phosphate accumulation in CHO-m3 cells and antagonism of the agonist-induced inhibition of forskolin-stimulated cyclic AMP accumulation in CHO-m2 cells. Darifenacin was the most M3-selective antagonist (32.4-fold), whereas oxybutynin, atropine, and tolterodine exhibited lesser selectivity. Functional affinity estimates in guinea pig urinary bladder and submandibular salivary gland using indices of phosphoinositide turnover revealed that oxybutynin, darifenacin, and tolterodine each displayed selectivity for the response in the bladder, relative to that seen in the submandibular gland (9.3-, 7.9-, and 7.4-fold, respectively). In contrast, atropine displayed a similar affinity in both tissues. These data demonstrate that in bladder, compared with submandibular gland from a single species, the mACh receptor antagonists darifenacin, tolterodine, and oxybutynin display selectivity to inhibit agonist-mediated phosphoinositide responses. It is proposed that both responses are mediated via M3 mACh receptor activation and that differential functional affinities displayed by some, but not all, antagonists are indicative of the influence of cell background upon the pharmacology of the M3 mACh receptor.
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Affiliation(s)
- Carl P Nelson
- Department of Cell Physiology and Pharmacology, University of Leicester, University Road, Leicester, LE1 9HN, UK
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Olapade-Olaopa EO, Nelson CP, Adebayo SA, Fakolujo AD, Bloom DA. EUTUBS: a mnemonic for the complete endoscopic examination of the lower urinary tract. West Afr J Med 2002; 21:294-6. [PMID: 12665268 DOI: 10.4314/wajm.v21i4.28002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Urethrocystoscopy is now routinely done in standard Urological practice. The availability of the flexible cystoscope for outpatient procedures has further increased the number of cystoscopists. However, there are currently no formal training schedules for urethrocystoscopy. This mnemonic has been developed to serve as a template for complete endoscopic examination of the lower urinary tract to which the cystoscopist may refer when undertaking this operation. It focuses on the common abnormalities that the endoscopist may encounter, and is not intended to be an exhaustive list of all abnormalities of the lower urinary tract. Furthermore, it is not meant to obviate the need for practical training of those wishing to carry out the procedure as part of their clinical practice.
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Affiliation(s)
- E O Olapade-Olaopa
- Section of Urology, Department of Surgery, University of Michigan, Ann Arbor, MI, USA.
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Nelson WG, De Marzo AM, Deweese TL, Lin X, Brooks JD, Putzi MJ, Nelson CP, Groopman JD, Kensler TW. Preneoplastic prostate lesions: an opportunity for prostate cancer prevention. Ann N Y Acad Sci 2001; 952:135-44. [PMID: 11795433 DOI: 10.1111/j.1749-6632.2001.tb02734.x] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Environmental factors, especially the diet, play a prominent role in the epidemic of prostate cancer (PCA), in the United States. Many candidate dietary components have been proposed to influence human prostatic carcinogenesis, including fat, calories, fruits and vegetables, anti-oxidants, and various micronutrients, but the specific roles dietary agents play in promoting or preventing PCA remain controversial. We have collected evidence to suggest that GSTP1, the gene encoding the pi-class glutathione S-transferase (GST), may serve a "caretaker" function for prostatic cells. Although GSTP1 can be detected in normal prostatic epithelium, in almost all PCA cases, PCA cells fail to express GSTP1 polypeptides, and lack of GSTP1 expression most often appears to be the result of somatic "CpG island" DNA methylation changes. Loss of GSTP1 function also appears to be characteristic of prostatic epithelial neoplasia (PIN) lesions, thought to represent PCA precursors. We have recently learned that a new candidate early PCA precursor lesion, proliferative inflammatory atrophy (PIA), characterized by proliferating prostatic cells juxtaposed to inflammatory cells, contains epithelial cells that express high levels of GSTP1. These findings have formed the basis for a new model of prostatic carcinogenesis, in which prostatic cells in PIA lesions, subjected to a barrage of inflammatory oxidants, induce GSTP1 expression as a defense against oxidative genome damage. When cells with defective GSTP1 genes appear amongst the PIA cells, such cells become vulnerable to oxidants and electrophiles that inflict genome damage that tends to promote neoplastic transformation to PIN and PCA cells. Subsequently, PIN and PCA cells with defective GSTPI genes remain vulnerable to similar stresses tending to promote malignant progression. This new model for prostatic carcinogenesis has implications for the design of new prostate cancer prevention strategies. Rational prevention approaches might include: (i) restoration of GSTPI expression via treatment with inhibitors of CpG methylation, (ii) compensation for inadequate GSTPI activity via treatment with inducers of general GST activity, and (iii) abrogation of genome-damaging stresses via avoidance of exogenous carcinogens and/or reduction of endogenous carcinogenic (particularly oxidant) stresses.
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Affiliation(s)
- W G Nelson
- The Johns Hopkins Comprehensive Cancer Center, Baltimore, Maryland 21231-1000, USA.
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Nelson CP, Bloom DA. Sales and science: changing patterns of pharmaceutical and medical device advertising in peer reviewed urology publications, 1975-2000. J Urol 2001; 166:2317-20. [PMID: 11696770 DOI: 10.1016/s0022-5347(05)65569-3] [Citation(s) in RCA: 6] [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] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
PURPOSE The effects of advertising on urological practice are controversial. We studied patterns of pharmaceutical and medical device marketing in peer reviewed urological journals in 1975 and 2000. MATERIALS AND METHODS Pharmaceutical and medical device advertising in 1 European and 2 American peer reviewed urological journals were evaluated in 4 randomly selected issues of each journal published in 1975 and 2000, respectively. Advertising quantity and the qualitative characteristics of each advertisement were analyzed. RESULTS We analyzed 574 advertisements in 24 issues. Advertising decreased between 1975 and 2000 based on the number of pages per issue (55.3 to 31.9, p = 0.04), number of advertisements per issue (30.4 to 17.4, p = 0.0098) and the ratio of advertising-to-scientific pages (0.399 to 0.151, p = 0.0016). Mean advertisement length was stable at 1.8 pages. The top 3 advertisers in 1975 were Eaton, Roche and Warner compared with Pfizer, AstraZeneca and Merck in 2000. Advertising for antibiotics comprised 70.3% of all pharmaceutical advertisements in 1975 but only 15.2% in 2000 (p = 0.0001), while advertising for benign prostatic hyperplasia, erectile dysfunction and hormonal therapy increased sharply. Nutritional supplement marketing increased from 0.5% of all advertisements in 1975 to 4.3% in 2000 (p = 0.0026). The incidence of advertisements citing peer reviewed literature increased from 16.7% to 33% (p = 0.0001) with a greater increase in the European than in the American journals. CONCLUSIONS Advertising in peer reviewed urological journals has decreased since 1975 and fewer companies now market more products. Few advertisements cite the scientific literature. Better understanding of pharmaceutical marketing patterns may improve awareness of these efforts to influence physician practice.
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Affiliation(s)
- C P Nelson
- Department of Urology, University of Michigan, Ann Arbor, Michigan, USA
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Abstract
BACKGROUND Glutathione S-transferases (GSTs), inducible enzymes that catalyze the detoxification of reactive electrophiles and oxidants, protect against neoplastic transformation. Prostatic adenocarcinoma and high-grade prostatic intraepithelial neoplasia (HGPIN) fail to express GSTP1, a major class of GST. This failure of expression is associated with methlyation of the GSTP1 promoter, a somatic alteration proposed to be a critical step in prostatic carcinogenesis. However, simple atrophy and post-atrophic hyperplasia-proliferative lesions associated with chronic inflammation, which we have termed "proliferative inflammatory atrophy" (PIA)-express elevated levels of GSTP1. We postulated that this increase in GSTP1 expression in PIA occurs in response to increased oxidative stress. We examined the expression of another major class of GST, GSTA1, in the human prostate. METHODS We performed immunohistochemistry against GSTA1 on formalin-fixed radical prostatectomies (n = 45). A stereological grid point counting method was used to estimate the percent of cells staining positive for GSTA1 in normal prostate, PIA, HGPIN, and adenocarcinoma. RESULTS In contrast to GSTP1, normal peripheral zone epithelium was virtually devoid of GSTA1. Strikingly, though, epithelial cells in PIA demonstrated strong staining for GSTA1 (median of percent of cells staining positive = 44) as compared to those in normal peripheral zone (median = 3.0, P <.00001), HGPIN (median = 2.9, P <.00001), and adenocarcinoma (median = 3.8, P <.00001). Variations in GSTA1 were also detected between normal anatomic zones: the central zone showed an increase in the percentage of cells staining positive (median = 20.9) as compared to the transition (median = 0.47, P <.0002) and the peripheral (P <.0001) zones. CONCLUSIONS Expression of GSTA1 is increased in PIA, supporting the concept that cells within these lesions are subject to localized increases in oxidative stress. Low levels of GSTA1 and GSTP1 in HGPIN and adenocarcinoma suggest a broad lack of detoxification activity in these cells, which may be associated with carcinogenesis in the prostate.
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Affiliation(s)
- J K Parsons
- The Department of Urology, The Johns Hopkins Medical Institutions, Baltimore, Maryland, USA
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Abstract
PURPOSE To determine whether the use of intrathecal sufentanil, which allows the patient to move during shockwave lithostripsy (SWL), affects treatment outcomes and operative and recovery times compared with standard lidocaine spinal anesthesia. PATIENTS AND METHODS We retrospectively studied a series of 62 SWL procedures performed on an unmodified Dornier HM3 lithotripter. The mean calculus size was 10.7 mm. There were 46 renal calculi, 13 ureteral calculi, and 4 patients with calculi in both locations. Of the 63 procedures, 25 were performed using intrathecal sufentanil alone, and 37 were performed with intrathecal lidocaine with or without additional agents. We compared treatment outcomes, as well as treatment time, fluoroscopy time, postanesthesia care unit (PACU) time, time to voiding, and time to ambulation. RESULTS Sufentanil use was associated with a significantly higher rate of successful treatment, defined as residual fragments absent or <4 mm on follow-up imaging, compared with lodocaine: 68% v. 40% (p = 0.0394). There was no significant difference between the groups in treatment time or fluoroscopy time. Use of sufentanil was associated with significantly shorter PACU time, time to ambulation, and time to voiding postoperatively. These differences persisted when men and women were analyzed separately, although the differences were less significant in women. CONCLUSIONS The use of intrathecal sufentanil for anesthesia during SWL does not adversely affect treatment outcome; it is, in fact, associated with better outcomes. The advantages of this agent in shortening recovery times and in easing patient transfer into the HM3 gantry argue for increasing its use.
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Affiliation(s)
- C P Nelson
- Department of Surgery, University of Michigan, Ann Arbor, USA
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Nelson CP, Kidd LC, Sauvageot J, Isaacs WB, De Marzo AM, Groopman JD, Nelson WG, Kensler TW. Protection against 2-hydroxyamino-1-methyl-6-phenylimidazo[4,5-b]pyridine cytotoxicity and DNA adduct formation in human prostate by glutathione S-transferase P1. Cancer Res 2001; 61:103-9. [PMID: 11196146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
The prostate has been identified as a target for 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)-induced carcinogenesis. Humans are exposed to PhIP through ingestion of well-done cooked meats, and there is evidence from epidemiological studies that implicates red meat consumption in prostate carcinogenesis. The alpha and pi class isoforms of glutathione S-transferases (GSTs) have been shown to inhibit adduction of activated PhIP metabolites to DNA in cell-free systems. In humans, silencing of GST pi(GSTP1) through CpG island hypermethylation is found in nearly all prostate carcinomas and is believed to be an early event in prostate carcinogenesis. We hypothesized that suppressed GSTP1 expression in prostate cells would increase their vulnerability to cytotoxicity and DNA adduct formation mediated by activated PhIP metabolites. To test this hypothesis, the human prostate adenocarcinoma cell line, LNCaP, which contains a silenced GSTP1 gene, was genetically modified to constitutively express high levels of GSTP1. Both LNCaP and LNCaP-GSTP1 cells exposed to N-OH-PhIP, but not parent PhIP, for 24 h showed a dose-dependent decrease in cell viability. GSTP1-overexpressing cells had LC50s 30-40% higher than cells transfected with the vector alone. PhIP-DNA adducts isolated from LNCaP-derived cells and primary human prostate tissue cultures exposed to N-OH-PhIP were analyzed by liquid chromatography/electrospray ionization mass spectrometry. Primary cultures of human prostate tissue and LNCaP-GSTP1 cells had approximately 50% lower adduct levels than parental LNCaP and vector control cells. Bioactivation assays using LNCaP cytosols showed that enzymatic activation of N-OH-PhIP to a DNA binding species was dependent on ATP and could be inhibited by recombinant human GSTP1 in the presence of glutathione. This evidence confirms that N-OH-PhIP can be bioactivated to a DNA binding species in human prostate and human prostate-derived cells. These observations provide the basis for using LNCaP and LNCaP-GSTP1 cells as a model system for studying the role of this enzyme in protection against N-OH-PhIP induced DNA damage in prostate carcinogenesis. Loss of GSTP1 expression in human prostate may, therefore, enhance its susceptibility to carcinogenic insult by compounds such as N-OH-PhIP. Conversely, induction of GSTs in early-stage prostate carcinogenesis may be a useful protective strategy.
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Affiliation(s)
- C P Nelson
- Department of Environmental Health Sciences, Johns Hopkins University School of Hygiene and Public Health, Baltimore, Maryland 21205, USA
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Abstract
The rabbit urinary bladder actively absorbs Na(+) from the urine. The rate-limiting step in this process is the diffusion of Na(+) across the apical membrane of bladder epithelial cells, mediated by amiloride-sensitive epithelial Na(+) channels. We have investigated the effects of cAMP on epithelial Na(+) channel activity in the rabbit bladder by measuring the amiloride-sensitive short-circuit current across bladders mounted in Ussing chambers. Three agents that raise intracellular cAMP levels (forskolin, dibutyryl-cAMP and 3-isobutyl-1-methylxanthine (IBMX)) increased the amiloride-sensitive short-circuit current relative to control preparations. The forskolin-induced increase in amiloride-sensitive short-circuit current was significantly inhibited by the vesicle fusion inhibitor brefeldin A and the protein synthesis inhibitor cycloheximide. These findings, together with the magnitude and protracted time course of the cAMP effects, suggests that cAMP stimulates the insertion of new Na(+) channels into the apical membrane of the rabbit bladder epithelium.
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Affiliation(s)
- T J Burton
- Department of Pharmacology, University of Cambridge, Tennis Court Road, CB2 1QJ, Cambridge, UK.
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Craig WY, Poulin SE, Nelson CP, Ritchie RF. ELISA of IgG antibody to oxidized low-density lipoprotein: effects of blocking buffer and method of data expression. Clin Chem 1994. [DOI: 10.1093/clinchem/40.6.882] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
We describe an ELISA for serum IgG antibodies against malondialdehyde-modified low-density lipoprotein (mLDL). Optimal antigen concentration, serum dilution, and dilution of enzyme-conjugated second antibody were 25 mg/L, 1:250, and 1:5000, respectively, when 5 g/L human serum albumin was used for blocking. When data were expressed as mLDL/LDL (the ratio of IgG binding to mLDL vs LDL), within-run and between-run CVs were 7.0% and 8.9%, respectively. Antibody concentrations expressed as mLDL/LDL or as mLDL-LDL (the difference between IgG binding to mLDL and to LDL) were higher in women with systemic lupus erythematosus (n = 20) than in controls (n = 20) (P < 0.001). With bovine serum albumin or Superblock blocking buffers, only the mLDL-LDL data were significant. Thus, the choice of blocking agent and the method of data expression should be carefully considered when assaying IgG antibodies against mLDL.
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Affiliation(s)
- W Y Craig
- Foundation for Blood Research, Scarborough, ME 04070-0190
| | - S E Poulin
- Foundation for Blood Research, Scarborough, ME 04070-0190
| | - C P Nelson
- Foundation for Blood Research, Scarborough, ME 04070-0190
| | - R F Ritchie
- Foundation for Blood Research, Scarborough, ME 04070-0190
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Craig WY, Poulin SE, Nelson CP, Ritchie RF. ELISA of IgG antibody to oxidized low-density lipoprotein: effects of blocking buffer and method of data expression. Clin Chem 1994; 40:882-8. [PMID: 8087982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
We describe an ELISA for serum IgG antibodies against malondialdehyde-modified low-density lipoprotein (mLDL). Optimal antigen concentration, serum dilution, and dilution of enzyme-conjugated second antibody were 25 mg/L, 1:250, and 1:5000, respectively, when 5 g/L human serum albumin was used for blocking. When data were expressed as mLDL/LDL (the ratio of IgG binding to mLDL vs LDL), within-run and between-run CVs were 7.0% and 8.9%, respectively. Antibody concentrations expressed as mLDL/LDL or as mLDL-LDL (the difference between IgG binding to mLDL and to LDL) were higher in women with systemic lupus erythematosus (n = 20) than in controls (n = 20) (P < 0.001). With bovine serum albumin or Superblock blocking buffers, only the mLDL-LDL data were significant. Thus, the choice of blocking agent and the method of data expression should be carefully considered when assaying IgG antibodies against mLDL.
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Affiliation(s)
- W Y Craig
- Foundation for Blood Research, Scarborough, ME 04070-0190
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Nelson CP, Saik RP, Greenburg AG, Hoyt DB, Coyle JJ. Truncal vagotomy causes biliary sludge formation. Curr Surg 1982; 39:30-3. [PMID: 7060397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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