1
|
de Araujo CIL, Teixeira HA, Toro OO, Liao C, Benetti LC, Borme J, Schafer D, Brandt I, Ferreira R, Alpuim P, Freitas PP, Pasa AA. Room temperature two terminal tunnel magnetoresistance in a lateral graphene transistor. Nanoscale 2021; 13:20028-20033. [PMID: 34842882 DOI: 10.1039/d1nr05495c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
We investigate the behavior of both pure spin and spin-polarized currents measured with four-probe non-local and two probe local configurations up to room temperature and under an external gate voltage in a lateral graphene transistor, produced using a standard large-scale microfabrication process. The high spin diffusion length of pristine graphene in the channel, measured both directly and by the Hanle effect, and the tuning of the relationship between the electrode resistance areas present in the device architecture allowed us to observe local tunnel magnetoresistance at room temperature, a new finding for this type of device. The results also indicate that while pure spin currents are less sensitive to temperature variations, spin-polarized current switching by an external voltage is more efficient, due to a combination of the Rashba effect and a change in carrier mobility by a Fermi level shift.
Collapse
Affiliation(s)
- C I L de Araujo
- Departamento de Fìsica, Laboratório de Spintrônica e Nanomagnetismo, Universidade Federal de Viçosa, Viçosa, 36570-900, Minas Gerais, Brazil.
| | - H A Teixeira
- Departamento de Fìsica, Laboratório de Spintrônica e Nanomagnetismo, Universidade Federal de Viçosa, Viçosa, 36570-900, Minas Gerais, Brazil.
| | - O O Toro
- Departamento de Fìsica, Laboratório de Spintrônica e Nanomagnetismo, Universidade Federal de Viçosa, Viçosa, 36570-900, Minas Gerais, Brazil.
| | - C Liao
- INL-International Iberian Nanotechnology Laboratory, 4715-330, Braga, Portugal
| | - L C Benetti
- INL-International Iberian Nanotechnology Laboratory, 4715-330, Braga, Portugal
- Laboratório de Filmes Finos e Superfícies (LFFS), Universidade Federal de Santa Catarina, Florianópolis 88040-900, Brazil
| | - J Borme
- INL-International Iberian Nanotechnology Laboratory, 4715-330, Braga, Portugal
| | - D Schafer
- Laboratório de Filmes Finos e Superfícies (LFFS), Universidade Federal de Santa Catarina, Florianópolis 88040-900, Brazil
| | - I Brandt
- Laboratório de Filmes Finos e Superfícies (LFFS), Universidade Federal de Santa Catarina, Florianópolis 88040-900, Brazil
| | - R Ferreira
- INL-International Iberian Nanotechnology Laboratory, 4715-330, Braga, Portugal
| | - P Alpuim
- INL-International Iberian Nanotechnology Laboratory, 4715-330, Braga, Portugal
| | - Paulo P Freitas
- INL-International Iberian Nanotechnology Laboratory, 4715-330, Braga, Portugal
| | - A A Pasa
- Laboratório de Filmes Finos e Superfícies (LFFS), Universidade Federal de Santa Catarina, Florianópolis 88040-900, Brazil
| |
Collapse
|
2
|
De Mey N, Cammu G, Brandt I, Belmans A, Van Mieghem C, Foubert L, De Decker K. High-sensitivity cardiac troponin release after conventional and minimally invasive cardiac surgery. Anaesth Intensive Care 2019; 47:255-266. [DOI: 10.1177/0310057x19845377] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
After cardiac surgery, a certain degree of myocardial injury is common. The arbitrarily proposed biomarker cut-off point in the Third Universal Definition for diagnosing coronary artery bypass grafting (CABG)–related perioperative myocardial infarction (PMI) is controversial and unvalidated for non-CABG surgery. Minimally invasive cardiac surgery is often thought to be associated with less myocardial damage compared to conventional surgical approaches. We conducted a real-life prospective study with serial sampling of high-sensitivity cardiac troponin T (hs-cTnT) in patients undergoing conventional and minimally invasive cardiac surgery. Four different types of cardiac surgery were performed in 400 patients (February 2014–January 2015): CABG, aortic valve replacement, minimally invasive mitral/tricuspid valve surgery through the HeartPort (HP) technique and combined CABG/valve surgery. Each group was further subdivided for comparison between the different surgical techniques. Blood samples were collected consecutively at intensive care unit (ICU) admission and 3, 6, 9, 12, 18, 24 and 48 h thereafter. The hs-cTnT values by peak timepoint differed significantly depending on the surgical approach. The overall peak timepoint for hs-cTnT occurred 6 h after ICU admission. The combined surgery and multiple-valve HP groups had the highest values (medians of 1067.5 (744.9–1455) ng/L and 1166 (743.7–2470) ng/L, respectively). The peak hs-cTnT values for patients developing PMI showed high variability. Differentiation between cardiac surgery–related necrosis and PMI remains challenging. This study emphasizes the importance of a clinically reliable biomarker cut-off value in addition to electrocardiography and echocardiography to optimize PMI diagnosis.
Collapse
Affiliation(s)
- Nathalie De Mey
- Departments of Anaesthesia and Critical Care Medicine, OLV Hospital, Aalst, Belgium
| | - Guy Cammu
- Departments of Anaesthesia and Critical Care Medicine, OLV Hospital, Aalst, Belgium
| | - Inger Brandt
- Department of Clinical Chemistry, OLV Hospital, Aalst, Belgium
| | - Ann Belmans
- Department of I-BioStat, University Hospital of Leuven and Hasselt, Leuven, Belgium
| | | | - Luc Foubert
- Departments of Anaesthesia and Critical Care Medicine, OLV Hospital, Aalst, Belgium
| | - Koen De Decker
- Departments of Anaesthesia and Critical Care Medicine, OLV Hospital, Aalst, Belgium
| |
Collapse
|
3
|
Pauselius-Fuchs U, Seiler A, Proebstl C, Donnerbauer E, Von Meyer A, Falbo R, Brandt I, Song J, Klopprogge K, Zimmermann S, Horstmann M, Mccaughey A. The cobas® SonicWash reduces sample carryover on cobas C 503 and cobas ISE analytical unit. Clin Chim Acta 2019. [DOI: 10.1016/j.cca.2019.03.127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
4
|
Lorenz O, Von Meyer A, Giacobone C, Bussetti M, Falbo R, Van Causbroeck G, Brandt I, Kim S, Song J, Klopprogge K, Metz P. Comparability of selected assays on the cobas pro® integrated solutions under routine like conditions. Clin Chim Acta 2019. [DOI: 10.1016/j.cca.2019.03.137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
5
|
Schiemsky T, Brandt I. Bicarbonate interference on cobas 6000 c501 chloride ion-selective electrodes. Clin Chem Lab Med 2018; 56:e214-e215. [PMID: 29466234 DOI: 10.1515/cclm-2018-0004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 01/29/2018] [Indexed: 11/15/2022]
Affiliation(s)
- Toon Schiemsky
- Onze Lieve Vrouwziekenhuis Hospital Aalst, Department of Laboratory Medicine, Aalst, Belgium
| | - Inger Brandt
- Onze Lieve Vrouwziekenhuis Hospital Aalst, Department of Laboratory Medicine, Moorselbaan 164, 9300 Aalst, Belgium, Phone: +32 53 72 42 80, Fax: +32 53 72 45 88
| |
Collapse
|
6
|
Jelenkovic A, Yokoyama Y, Sund R, Hur YM, Harris JR, Brandt I, Nilsen TS, Ooki S, Ullemar V, Almqvist C, Magnusson PKE, Saudino KJ, Stazi MA, Fagnani C, Brescianini S, Nelson TL, Whitfield KE, Knafo-Noam A, Mankuta D, Abramson L, Cutler TL, Hopper JL, Llewellyn CH, Fisher A, Corley RP, Huibregtse BM, Derom CA, Vlietinck RF, Bjerregaard-Andersen M, Beck-Nielsen H, Sodemann M, Krueger RF, McGue M, Pahlen S, Alexandra Burt S, Klump KL, Dubois L, Boivin M, Brendgen M, Dionne G, Vitaro F, Willemsen G, Bartels M, van Beijsterveld CEM, Craig JM, Saffery R, Rasmussen F, Tynelius P, Heikkilä K, Pietiläinen KH, Bayasgalan G, Narandalai D, Haworth CMA, Plomin R, Ji F, Ning F, Pang Z, Rebato E, Tarnoki AD, Tarnoki DL, Kim J, Lee J, Lee S, Sung J, Loos RJF, Boomsma DI, Sørensen TIA, Kaprio J, Silventoinen K. Associations between birth size and later height from infancy through adulthood: An individual based pooled analysis of 28 twin cohorts participating in the CODATwins project. Early Hum Dev 2018; 120:53-60. [PMID: 29656171 PMCID: PMC6532975 DOI: 10.1016/j.earlhumdev.2018.04.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [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: 09/25/2017] [Revised: 04/06/2018] [Accepted: 04/07/2018] [Indexed: 11/24/2022]
Abstract
BACKGROUND There is evidence that birth size is positively associated with height in later life, but it remains unclear whether this is explained by genetic factors or the intrauterine environment. AIM To analyze the associations of birth weight, length and ponderal index with height from infancy through adulthood within mono- and dizygotic twin pairs, which provides insights into the role of genetic and environmental individual-specific factors. METHODS This study is based on the data from 28 twin cohorts in 17 countries. The pooled data included 41,852 complete twin pairs (55% monozygotic and 45% same-sex dizygotic) with information on birth weight and a total of 112,409 paired height measurements at ages ranging from 1 to 69 years. Birth length was available for 19,881 complete twin pairs, with a total of 72,692 paired height measurements. The association between birth size and later height was analyzed at both the individual and within-pair level by linear regression analyses. RESULTS Within twin pairs, regression coefficients showed that a 1-kg increase in birth weight and a 1-cm increase in birth length were associated with 1.14-4.25 cm and 0.18-0.90 cm taller height, respectively. The magnitude of the associations was generally greater within dizygotic than within monozygotic twin pairs, and this difference between zygosities was more pronounced for birth length. CONCLUSION Both genetic and individual-specific environmental factors play a role in the association between birth size and later height from infancy to adulthood, with a larger role for genetics in the association with birth length than with birth weight.
Collapse
Affiliation(s)
- A Jelenkovic
- Department of Social Research, University of Helsinki, Helsinki, Finland, Department of Genetics, Physical Anthropology and Animal Physiology, University of the Basque Country UPV/EHU, Leioa, Spain
| | - Y Yokoyama
- Department of Public Health Nursing, Osaka City University, Osaka, Japan
| | - R Sund
- Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland
| | - YM Hur
- Department of Education, Mokpo National University, Jeonnam, South Korea
| | - JR Harris
- Norwegian Institute of Public Health, Oslo, Norway
| | - I Brandt
- Norwegian Institute of Public Health, Oslo, Norway
| | - TS Nilsen
- Norwegian Institute of Public Health, Oslo, Norway
| | - S Ooki
- Department of Health Science, Ishikawa Prefectural Nursing University, Kahoku, Ishikawa, Japan
| | - V Ullemar
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - C Almqvist
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden, Pediatric Allergy and Pulmonology Unit at Astrid Lindgren Children’s Hospital, Karolinska University Hospital, Stockholm, Sweden
| | - PKE Magnusson
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - KJ Saudino
- Boston University, Department of Psychological and Brain Sciences, Boston, MA, USA
| | - MA Stazi
- Istituto Superiore di Sanità - Centre for Behavioural Sciences and Mental Health, Rome, Italy
| | - C Fagnani
- Istituto Superiore di Sanità - Centre for Behavioural Sciences and Mental Health, Rome, Italy
| | - S Brescianini
- Istituto Superiore di Sanità - Centre for Behavioural Sciences and Mental Health, Rome, Italy
| | - TL Nelson
- Department of Health and Exercise Sciences, Colorado School of Public Health, Colorado State University, USA
| | - KE Whitfield
- Psychology and Neuroscience, Duke University, Durham, NC, USA
| | - A Knafo-Noam
- The Hebrew University of Jerusalem, Jerusalem, Israel
| | - D Mankuta
- Hadassah Hospital Obstetrics and Gynecology Department, Hebrew University Medical School, Jerusalem, Israel
| | - L Abramson
- The Hebrew University of Jerusalem, Jerusalem, Israel
| | - TL Cutler
- The Australian Twin Registry, Centre for Epidemiology and Biostatistics, The University of Melbourne, Melbourne, Victoria, Australia
| | - JL Hopper
- The Australian Twin Registry, Centre for Epidemiology and Biostatistics, The University of Melbourne, Melbourne, Victoria, Australia, Department of Epidemiology, School of Public Health, Seoul National University, Seoul, South Korea
| | - CH Llewellyn
- Health Behaviour Research Centre, Department of Epidemiology and Public Health, Institute of Epidemiology and Health Care, University College London, London, UK
| | - A Fisher
- Health Behaviour Research Centre, Department of Epidemiology and Public Health, Institute of Epidemiology and Health Care, University College London, London, UK
| | - RP Corley
- Institute of Behavioral Science, University of Colorado, Boulder, CO, USA
| | - BM Huibregtse
- Institute of Behavioral Science, University of Colorado, Boulder, CO, USA
| | - CA Derom
- Centre of Human Genetics, University Hospitals Leuven, Leuven, Belgium, Department of Obstetrics and Gynaecology, Ghent University Hospitals, Ghent, Belgium
| | - RF Vlietinck
- Centre of Human Genetics, University Hospitals Leuven, Leuven, Belgium
| | - M Bjerregaard-Andersen
- Bandim Health Project, INDEPTH Network, Bissau, Guinea-Bissau, Research Center for Vitamins and Vaccines, Statens Serum Institute, Copenhagen, Denmark, Department of Endocrinology, Odense University Hospital, Odense, Denmark
| | - H Beck-Nielsen
- Department of Endocrinology, Odense University Hospital, Odense, Denmark
| | - M Sodemann
- Department of Infectious Diseases, Odense University Hospital, Odense, Denmark
| | - RF Krueger
- Department of Psychology, University of Minnesota, Minneapolis, MN, USA
| | - M McGue
- Department of Psychology, University of Minnesota, Minneapolis, MN, USA
| | - S Pahlen
- Department of Psychology, University of Minnesota, Minneapolis, MN, USA
| | | | - KL Klump
- Michigan State University, East Lansing, MI, USA
| | - L Dubois
- School of Epidemiology, Public Health and Preventive Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - M Boivin
- École de psychologie, Université Laval, Québec, Canada, Institute of Genetic, Neurobiological, and Social Foundations of Child Development, Tomsk State University, Russian Federation
| | - M Brendgen
- Département de psychologie, Université du Québec à Montréal, Montréal, Québec, Canada
| | - G Dionne
- École de psychologie, Université Laval, Québec, Canada
| | - F Vitaro
- École de psychoéducation, Université de Montréal, Montréal, Québec, Canada
| | - G Willemsen
- Department of Biological Psychology, VU University Amsterdam, Amsterdam, Netherlands
| | - M Bartels
- Department of Biological Psychology, VU University Amsterdam, Amsterdam, Netherlands
| | - CEM van Beijsterveld
- Department of Biological Psychology, VU University Amsterdam, Amsterdam, Netherlands
| | - JM Craig
- Murdoch Childrens Research Institute, Royal Children’s Hospital, Parkville, Victoria, Australia, Department of Paediatrics, University of Melbourne, Parkville, Victoria, Australia
| | - R Saffery
- Murdoch Childrens Research Institute, Royal Children’s Hospital, Parkville, Victoria, Australia, Department of Paediatrics, University of Melbourne, Parkville, Victoria, Australia
| | - F Rasmussen
- Department of Health Sciences, Lund University, Sweden
| | - P Tynelius
- Department of Public Health Sciences, Karolinska Institutet, Stockholm, Sweden
| | - K Heikkilä
- Department of Public Health, University of Helsinki, Helsinki, Finland
| | - KH Pietiläinen
- Obesity Research Unit, Research Programs Unit, University of Helsinki, Helsinki, Finland
| | - G Bayasgalan
- Healthy Twin Association of Mongolia, Ulaanbaatar, Mongolia
| | - D Narandalai
- Healthy Twin Association of Mongolia, Ulaanbaatar, Mongolia, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - CMA Haworth
- MRC Integrative Epidemiology Unit, University of Bristol, Bristol, UK
| | - R Plomin
- King’s College London, MRC Social, Genetic & Developmental Psychiatry Centre, Institute of Psychiatry, Psychology & Neuroscience, London, UK
| | - F Ji
- Department of Noncommunicable Diseases Prevention, Qingdao Centers for Disease Control and Prevention, Qingdao, China
| | - F Ning
- Department of Noncommunicable Diseases Prevention, Qingdao Centers for Disease Control and Prevention, Qingdao, China
| | - Z Pang
- Department of Noncommunicable Diseases Prevention, Qingdao Centers for Disease Control and Prevention, Qingdao, China
| | - E Rebato
- Department of Genetics, Physical Anthropology and Animal Physiology, University of the Basque Country UPV/EHU, Leioa, Spain
| | - AD Tarnoki
- Department of Radiology, Semmelweis University, Budapest, Hungary, Hungarian Twin Registry, Budapest, Hungary
| | - DL Tarnoki
- Department of Radiology, Semmelweis University, Budapest, Hungary, Hungarian Twin Registry, Budapest, Hungary
| | - J Kim
- Department of Epidemiology, School of Public Health, Seoul National University, Seoul, South Korea
| | - J Lee
- Department of Epidemiology, School of Public Health, Seoul National University, Seoul, South Korea
| | - S Lee
- Department of Epidemiology, School of Public Health, Seoul National University, Seoul, South Korea
| | - J Sung
- Department of Epidemiology, School of Public Health, Seoul National University, Seoul, South Korea, Institute of Health and Environment, Seoul National University, Seoul, South Korea
| | - RJF Loos
- The Charles Bronfman Institute for Personalized Medicine, The Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - DI Boomsma
- Department of Biological Psychology, VU University Amsterdam, Amsterdam, Netherlands
| | - TIA Sørensen
- Novo Nordisk Foundation Centre for Basic Metabolic Research (Section of Metabolic Genetics), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark, Department of Public Health (Section of Epidemiology), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - J Kaprio
- Department of Public Health, University of Helsinki, Helsinki, Finland, Institute for Molecular Medicine FIMM, Helsinki, Finland
| | - K Silventoinen
- Department of Social Research, University of Helsinki, Helsinki, Finland, Osaka University Graduate School of Medicine, Osaka University, Osaka, Japan
| |
Collapse
|
7
|
Van Elzen R, Schoenmakers E, Brandt I, Van Der Veken P, Lambeir AM. Ligand-induced conformational changes in prolyl oligopeptidase: a kinetic approach. Protein Eng Des Sel 2017; 30:217-224. [PMID: 28062644 DOI: 10.1093/protein/gzw079] [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] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Accepted: 12/17/2016] [Indexed: 11/14/2022] Open
Abstract
Most kinetic studies of prolyl oligopeptidase (PREP) were performed with the porcine enzyme using modified peptide substrates. Yet recent biophysical studies used the human homolog. Therefore, the aim of this study was to compare the kinetic behavior of human and porcine PREP, as well as to find a suitable method to study enzyme kinetics with an unmodified biological substrate. It was found that human PREP behaves identically to the porcine homolog, displaying a double bell-shaped pH profile and a pH-dependent solvent kinetic isotope effect of the kcat/Km, features that set it apart from the related exopeptidase dipeptidyl peptidase IV (DPP IV). However, the empirical temperature coefficient Q10, describing the temperature dependency of the kinetic parameters and the non-linear Arrhenius plot of kcat/Km are common characteristics between PREP and DPP IV. The results also demonstrate the feasibility of microcalorimetry for measuring turn-over of proline containing peptides.
Collapse
Affiliation(s)
- R Van Elzen
- Department of Pharmaceutical Sciences, University of Antwerp, Universiteitsplein 1, B-2610 Wilrijk, Belgium
| | - E Schoenmakers
- Department of Pharmaceutical Sciences, University of Antwerp, Universiteitsplein 1, B-2610 Wilrijk, Belgium
| | - I Brandt
- Department of Pharmaceutical Sciences, University of Antwerp, Universiteitsplein 1, B-2610 Wilrijk, Belgium
| | - P Van Der Veken
- Department of Pharmaceutical Sciences, University of Antwerp, Universiteitsplein 1, B-2610 Wilrijk, Belgium
| | - A M Lambeir
- Department of Pharmaceutical Sciences, University of Antwerp, Universiteitsplein 1, B-2610 Wilrijk, Belgium
| |
Collapse
|
8
|
Peeters B, Brandt I, Desmet K, Harteveld CL, Kieffer D. Hb Melusine and Hb Athens-Georgia: potentially underreported in the Belgian population? Four cases demonstrating the lack of detection using common CE-HPLC methods either for glycated hemoglobin (HbA 1C) analysis or Hb variant screening. Acta Clin Belg 2016; 71:458-461. [PMID: 27368113 DOI: 10.1080/17843286.2016.1203559] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
OBJECTIVE AND IMPORTANCE Suspected hemoglobin (Hb) variants, detected during HbA1C measurements should be further investigated, determining the extent of the interference with each method. CLINICAL PRESENTATION This is the first report of Hb Melusine and Hb Athens-Georgia in Caucasian Belgian patients. Intervention & Technique: Since common CE-HPLC methods for HbA1C analysis or Hb variant screening are apparently unable to detect these Hb variants, their presence might be underestimated. HbA1C analysis using CZE, however, alerted for their presence. Moreover, in case of Hb Melusine, even Hb variant screening using CZE was unsuccessful in its detection. CONCLUSION Fortunately, carriage of Hb Melusine or Hb Athens-Georgia variants has no clinical implications and, as shown in this report, no apparent difference in HbA1C should be expected.
Collapse
|
9
|
De Beenhouwer T, Hofmans M, De Bleecker J, Brandt I, Van Mieghem C. Myopathy mimicking an acute coronary syndrome. Acta Clin Belg 2016; 71:426-427. [PMID: 27104632 DOI: 10.1080/17843286.2015.1115629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
10
|
Oyaert M, Brandt I, Vermeersch P, Desmet K, Vanstapel F, Pauwels S. Practical approach for medical validation of therapeutic drug monitoring results. ACTA ACUST UNITED AC 2016; 54:e97-e100. [DOI: 10.1515/cclm-2015-0660] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 08/26/2015] [Indexed: 11/15/2022]
|
11
|
Baerts L, Waumans Y, Brandt I, Jungraithmayr W, Van der Veken P, Vanderheyden M, De Meester I. Circulating Stromal Cell-Derived Factor 1α Levels in Heart Failure: A Matter of Proper Sampling. PLoS One 2015; 10:e0141408. [PMID: 26544044 PMCID: PMC4636157 DOI: 10.1371/journal.pone.0141408] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 10/08/2015] [Indexed: 12/26/2022] Open
Abstract
Background The chemokine Stromal cell-derived factor 1α (SDF1α, CXCL12) is currently under investigation as a biomarker for various cardiac diseases. The correct interpretation of SDF1α levels is complicated by the occurrence of truncated forms that possess an altered biological activity. Methodology We studied the immunoreactivities of SDF1α forms and evaluated the effect of adding a DPP4 inhibitor in sampling tubes on measured SDF1α levels. Using optimized sampling, we measured DPP4 activity and SDF1α levels in patients with varying degrees of heart failure. Results The immunoreactivities of SDF1α and its degradation products were determined with three immunoassays. A one hour incubation of SDF1α with DPP4 at 37°C resulted in 2/3 loss of immunoreactivity in each of the assays. Incubation with serum gave a similar result. Using appropriate sampling, SDF1α levels were found to be significantly higher in those heart failure patients with a severe loss of left ventricular function. DPP4 activity in serum was not altered in the heart failure population. However, the DPP4 activity was found to be significantly decreased in patients with high SDF1α levels Conclusions We propose that all samples for SDF1α analysis should be collected in the presence of at least a DPP4 inhibitor. In doing so, we found higher SDF1α levels in subgroups of patients with heart failure. Our work supports the need for further research on the clinical relevance of SDF1α levels in cardiac disease.
Collapse
Affiliation(s)
- Lesley Baerts
- Laboratory of Medical Biochemistry, University of Antwerp, Antwerp, Belgium
| | - Yannick Waumans
- Laboratory of Medical Biochemistry, University of Antwerp, Antwerp, Belgium
| | - Inger Brandt
- Laboratory of Clinical Chemistry, OLV Hospital Aalst, Aalst, Belgium
| | | | | | | | - Ingrid De Meester
- Laboratory of Medical Biochemistry, University of Antwerp, Antwerp, Belgium
- * E-mail:
| |
Collapse
|
12
|
Mey N, Brandt I, Mieghem C, Decker K, Cammu G, Foubert L. High-sensitive cardiac troponins and CK-MB concentrations in patients undergoing cardiac surgery. Crit Care 2015. [PMCID: PMC4470713 DOI: 10.1186/cc14238] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
|
13
|
Wittock A, De Mey N, De Decker K, Brandt I, Van Mieghem C, Cammu G, Foubert L. HIGH-SENSITIVE CARDIAC TROPONINS IN PATIENTS UNDERGOING CARDIAC SURGERY: FRIEND OR FOE? Intensive Care Med Exp 2015. [PMCID: PMC4798166 DOI: 10.1186/2197-425x-3-s1-a952] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
|
14
|
Brandt C, Brandt I. Leben mit chronischer spinaler Muskelatrophie. MED GENET-BERLIN 2013. [DOI: 10.1007/s11825-013-0404-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Zusammenfassung
Eines der höchsten Ziele der individuellen menschlichen Entwicklung ist es, erwachsen zu werden, sein Leben selbstständig und eigenverantwortlich in die Hand zu nehmen und vielleicht sogar seinen Beitrag für die Gemeinschaft zu leisten. Dies kann aufgrund einer schweren Körperbehinderung, z. B. wenn wegen einer Muskelerkrankung nicht einmal die Gabel zum Essen gehalten werden kann, als praktisch schwierig und für nicht umsetzbar angesehen werden. Ins Erwachsenenalter zu kommen und auch Erwachsen zu sein, d. h. eigenverantwortlich und selbstbestimmt zu leben, ist aber durchaus möglich, auch wenn die rein körperliche Kraft dazu fehlt.
Wir berichten über unser Leben mit einer spinalen Muskelatrophie (SMA) vom Typ II, 3 Survival-motor-neuron-2(SMN2)-Genkopien, ein Leben voller Herausforderungen und Abhängigkeiten und doch ein ganz normales Leben.
Collapse
Affiliation(s)
- C. Brandt
- Aff1 - Hinter Hoben 161 53129 Bonn Deutschland
| | - I. Brandt
- Aff1 - Hinter Hoben 161 53129 Bonn Deutschland
| |
Collapse
|
15
|
Berg C, Säfholm M, Jansson E, Olsson A, Fick J, Brandt I. Combined exposure to progestin and oestrogen mixtures: Effects on vitellogenin and hormone receptor mRNA expression. Comp Biochem Physiol A Mol Integr Physiol 2012. [DOI: 10.1016/j.cbpa.2012.05.166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
16
|
Schouwers S, Brandt I, Willemse J, Van Regenmortel N, Uyttenbroeck W, Wauters A, Neels H. Influence of separator gel in Sarstedt S-Monovette® serum tubes on various therapeutic drugs, hormones, and proteins. Clin Chim Acta 2012; 413:100-4. [DOI: 10.1016/j.cca.2011.08.037] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Revised: 08/31/2011] [Accepted: 08/31/2011] [Indexed: 11/26/2022]
|
17
|
Asp V, Cantillana T, Bergman A, Brandt I. Chiral effects in adrenocorticolytic action of o,p'-DDD (mitotane) in human adrenal cells. Xenobiotica 2010; 40:177-83. [PMID: 20044879 DOI: 10.3109/00498250903470230] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Adrenocortical carcinoma (ACC) is a rare malignant disease with poor prognosis. The main pharmacological choice, o,p'-DDD (mitotane), produces severe adverse effects. Since o,p'-DDD is a chiral molecule and stereoisomers frequently possess different pharmacokinetic and/or pharmacodynamic properties, we isolated the two o,p'-DDD enantiomers, (R)-(+)-o,p'-DDD and (S)-(-)-o,p'-DDD, and determined their absolute structures. The effects of each enantiomer on cell viability and on cortisol and dehydroepiandrosterone (DHEA) secretion in the human adrenocortical cell line H295R were assessed. We also assayed the o,p'-DDD racemate and the m,p'- and p,p'-isomers. The results show small but statistically significant differences in activity of the o,p'-DDD enantiomers for all parameters tested. The three DDD isomers were equally potent in decreasing cell viability, but p,p'-DDD affected hormone secretion slightly less than the o,p'- and m,p'-isomers. The small chiral differences in direct effects on target cells alone do not warrant single enantiomer administration, but might reach importance in conjunction with possible stereochemical effects on pharmacokinetic processes in vivo.
Collapse
Affiliation(s)
- V Asp
- Environmental Toxicology, Uppsala University, Uppsala, Sweden
| | | | | | | |
Collapse
|
18
|
Cantillana T, Lindström V, Eriksson L, Brandt I, Bergman A. Interindividual differences in o,p'-DDD enantiomer kinetics examined in Göttingen minipigs. Chemosphere 2009; 76:167-172. [PMID: 19394667 DOI: 10.1016/j.chemosphere.2009.03.050] [Citation(s) in RCA: 5] [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] [Subscribe] [Scholar Register] [Received: 12/19/2008] [Revised: 02/20/2009] [Accepted: 03/25/2009] [Indexed: 05/27/2023]
Abstract
Five minipigs were given a single oral dose of a racemic mixture of o,p'-DDD (30 mg kg(-1)b.w., EF=0.49). Blood plasma and subcutaneous adipose tissue were collected for analysis, at different time-points over 180 d. At the end of the experiment also liver, kidney and brain tissue were collected. Low concentrations of o,p'-DDD still remained after 180 d in plasma (mean 0.5+/-0.3 ng g(-1)f.w.) and in adipose tissue (mean 40+/-40 ng g(-1)f.w.). The mean concentrations in liver and kidney were 500+/-300 pg g(-1)f.w. and 90+/-50 pg g(-1)f.w., respectively. The enantiomers of o,p'-DDD were isolated by HPLC and the absolute configuration of the enantiomers were determined by X-ray crystallography and polarimetry as R-(+)-o,p'-DDD and S-(-)-o,p'-DDD. The enantiomer fractions (EFs) of o,p'-DDD were determined in plasma, adipose tissue and kidney using GC/ECD equipped with a chiral column. The EFs of o,p'-DDD in the individual minipigs showed large variability, ranging from 0.2 to 0.6 after 24h in plasma and from 0.2 to 0.7 after 90 d in adipose tissue. Hence in two of the minipigs, the S-(-)-o,p'-DDD enantiomer was dominating while the other enantiomer, R-(+)-o,p'-DDD was dominating in three minipigs. We propose that a yet not identified factor related to polymorphism, regulating the metabolism and/or elimination of the enantiomeric o,p'-DDD, is responsible for the differences in enantiomeric retention of the compound in the minipigs.
Collapse
Affiliation(s)
- T Cantillana
- Department of Environmental Chemistry, Stockholm University, SE-106 91 Stockholm, Sweden.
| | | | | | | | | |
Collapse
|
19
|
Groh N, Brandt I, Beckmann MW, Schrauder M, Loehberg CR. Evaluation for synergistic suppression of breast cancer proliferation by Chloroquine in combination with the rapamycin derivative, Rad001. Geburtshilfe Frauenheilkd 2009. [DOI: 10.1055/s-0029-1225205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
|
20
|
Brandt I, Gérard M, Sergeant K, Devreese B, Baekelandt V, Augustyns K, Scharpé S, Engelborghs Y, Lambeir AM. Prolyl oligopeptidase stimulates the aggregation of alpha-synuclein. Peptides 2008; 29:1472-8. [PMID: 18571285 DOI: 10.1016/j.peptides.2008.05.005] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2008] [Revised: 05/05/2008] [Accepted: 05/07/2008] [Indexed: 12/20/2022]
Abstract
Despite its thorough enzymological and biochemical characterization the exact function of prolyl oligopeptidase (PO, E.C. 3.4.21.26) remains unclear. The positive effect of PO inhibitors on learning and memory in animal models for amnesia, enzyme activity measurements in patient samples and (neuro)peptide degradation studies link the enzyme with neurodegenerative disorders. The brain protein alpha-synuclein currently attracts much attention because of its proposed role in the pathology of Parkinson's disease. A fundamental question concerns how the essentially disordered protein is transformed into the highly organized fibrils that are found in Lewy bodies, the hallmarks of Parkinson's disease. Using gel electrophoresis and MALDI TOF/TOF mass spectrometry we investigated the possibility of alpha-synuclein as a PO substrate. We found that in vitro incubation of the protein with PO did not result in truncation of full-length alpha-synuclein. Surprisingly, however, we found an acceleration of the aggregation process of alpha-synuclein using turbidity measurements that was reversed by specific inhibitors of PO enzymatic activity. If PO displays this activity also in vivo, PO inhibitors might have an effect on neurodegenerative disorders through a decrease in the aggregation of alpha-synuclein.
Collapse
Affiliation(s)
- Inger Brandt
- Laboratory for Medical Biochemistry, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Van der Veken P, De Meester I, Dubois V, Soroka A, Van Goethem S, Maes MB, Brandt I, Lambeir AM, Chen X, Haemers A, Scharpé S, Augustyns K. Inhibitors of dipeptidyl peptidase 8 and dipeptidyl peptidase 9. Part 1: Identification of dipeptide derived leads. Bioorg Med Chem Lett 2008; 18:4154-8. [DOI: 10.1016/j.bmcl.2008.05.080] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2008] [Revised: 05/19/2008] [Accepted: 05/20/2008] [Indexed: 10/22/2022]
|
22
|
Gerard M, Debyser Z, Desender L, Baert J, Brandt I, Baekelandt V, Engelborghs Y. FK506 binding protein 12 differentially accelerates fibril formation of wild type alpha-synuclein and its clinical mutants A30P or A53T. J Neurochem 2008; 106:121-33. [DOI: 10.1111/j.1471-4159.2008.05342.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
|
23
|
Van der Veken P, Soroka A, Brandt I, Chen YS, Maes MB, Lambeir AM, Chen X, Haemers A, Scharpé S, Augustyns K, De Meester I. Irreversible Inhibition of Dipeptidyl Peptidase 8 by Dipeptide-Derived Diaryl Phosphonates. J Med Chem 2007; 50:5568-70. [DOI: 10.1021/jm701005a] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Pieter Van der Veken
- Laboratory of Medicinal Chemistry, and Laboratory of Medical Biochemistry, University of Antwerp (UA), Universiteitsplein 1, B-2610 Antwerp, Belgium, and Division of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Zhu Nan, Miaoli, Taiwan ROC350
| | - Anna Soroka
- Laboratory of Medicinal Chemistry, and Laboratory of Medical Biochemistry, University of Antwerp (UA), Universiteitsplein 1, B-2610 Antwerp, Belgium, and Division of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Zhu Nan, Miaoli, Taiwan ROC350
| | - Inger Brandt
- Laboratory of Medicinal Chemistry, and Laboratory of Medical Biochemistry, University of Antwerp (UA), Universiteitsplein 1, B-2610 Antwerp, Belgium, and Division of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Zhu Nan, Miaoli, Taiwan ROC350
| | - Yuan-Shou Chen
- Laboratory of Medicinal Chemistry, and Laboratory of Medical Biochemistry, University of Antwerp (UA), Universiteitsplein 1, B-2610 Antwerp, Belgium, and Division of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Zhu Nan, Miaoli, Taiwan ROC350
| | - Marie-Berthe Maes
- Laboratory of Medicinal Chemistry, and Laboratory of Medical Biochemistry, University of Antwerp (UA), Universiteitsplein 1, B-2610 Antwerp, Belgium, and Division of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Zhu Nan, Miaoli, Taiwan ROC350
| | - Anne-Marie Lambeir
- Laboratory of Medicinal Chemistry, and Laboratory of Medical Biochemistry, University of Antwerp (UA), Universiteitsplein 1, B-2610 Antwerp, Belgium, and Division of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Zhu Nan, Miaoli, Taiwan ROC350
| | - Xin Chen
- Laboratory of Medicinal Chemistry, and Laboratory of Medical Biochemistry, University of Antwerp (UA), Universiteitsplein 1, B-2610 Antwerp, Belgium, and Division of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Zhu Nan, Miaoli, Taiwan ROC350
| | - Achiel Haemers
- Laboratory of Medicinal Chemistry, and Laboratory of Medical Biochemistry, University of Antwerp (UA), Universiteitsplein 1, B-2610 Antwerp, Belgium, and Division of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Zhu Nan, Miaoli, Taiwan ROC350
| | - Simon Scharpé
- Laboratory of Medicinal Chemistry, and Laboratory of Medical Biochemistry, University of Antwerp (UA), Universiteitsplein 1, B-2610 Antwerp, Belgium, and Division of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Zhu Nan, Miaoli, Taiwan ROC350
| | - Koen Augustyns
- Laboratory of Medicinal Chemistry, and Laboratory of Medical Biochemistry, University of Antwerp (UA), Universiteitsplein 1, B-2610 Antwerp, Belgium, and Division of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Zhu Nan, Miaoli, Taiwan ROC350
| | - Ingrid De Meester
- Laboratory of Medicinal Chemistry, and Laboratory of Medical Biochemistry, University of Antwerp (UA), Universiteitsplein 1, B-2610 Antwerp, Belgium, and Division of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Zhu Nan, Miaoli, Taiwan ROC350
| |
Collapse
|
24
|
Bergström U, Olsson JA, Hvidsten TR, Komorowski J, Brandt I. Differential gene expression in the olfactory bulb following exposure to the olfactory toxicant 2,6-dichlorophenyl methylsulphone and its 2,5-dichlorinated isomer in mice. Neurotoxicology 2007; 28:1120-8. [PMID: 17655932 DOI: 10.1016/j.neuro.2007.05.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [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: 04/03/2007] [Revised: 04/30/2007] [Accepted: 05/29/2007] [Indexed: 11/24/2022]
Abstract
2,6-Dichlorophenyl methylsulphone and a number of structurally related chemicals are CYP-activated toxicants in the olfactory mucosa in mice and rats. This toxicity involves both the olfactory neuroepithelium and its subepithelial nerves. In addition, 2,6-dichlorophenyl methylsulphone induces glial acidic fibrillary protein expression (Gfap, a biomarker for gliosis) in the olfactory bulb, as well as long-lasting learning deficits and changes in spontaneous behavior in mice and rats. So far the 2,5-dichlorinated isomer has not been reported to cause toxicity in the olfactory system, although it gives rise to transient changes in spontaneous behavior. In the present study we used 15k cDNA gene arrays and real-time RT-PCR to determine 2,6-dichlorophenyl methylsulphone-induced effects on gene expression in the olfactory bulb in mice. Seven days following a single ip dose of 2,6-dichlorophenyl methylsulphone, 56 genes were found to be differentially expressed in the olfactory bulb. Forty-one of these genes clustered into specific processes regulating, for instance, cell differentiation, cell migration and apoptosis. The genes selected for real-time RT-PCR were chosen to cover the range of B-values in the cDNA array analysis. Altered expression of Gfap, mt-Rnr2, Ncor1 and Olfml3 was confirmed. The expression of these genes was measured also in mice dosed with 2,5-dichlorophenyl methylsulphone, and mt-Rnr2 and Olfml3 were found to be altered also by this isomer. Combined with previous data, the results support the possibility that the persistent neurotoxicity induced by 2,6-dichlorophenyl methylsulphone in mice represents both an indirect and a direct effect on the brain. The 2,5-dichlorinated isomer, negative with regard to CYP-catalyzed toxicity in the olfactory mucosa, may prove useful to resolve this issue.
Collapse
Affiliation(s)
- U Bergström
- Department of Environmental Toxicology, Uppsala University, Norbyv. 18A, 752 36 Uppsala, Sweden.
| | | | | | | | | |
Collapse
|
25
|
Maes MB, Dubois V, Brandt I, Lambeir AM, Van der Veken P, Augustyns K, Cheng JD, Chen X, Scharpé S, De Meester I. Dipeptidyl peptidase 8/9-like activity in human leukocytes. J Leukoc Biol 2007; 81:1252-7. [PMID: 17287297 DOI: 10.1189/jlb.0906546] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [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: 12/22/2022] Open
Abstract
The proline-specific dipeptidyl peptidases (DPPs) are emerging as a protease family with important roles in the regulation of signaling by peptide hormones. Inhibitors of DPPs have an intriguing, therapeutic potential, with clinical efficacy seen in patients with diabetes. Until now, only recombinant forms of DPP8 and DPP9 have been characterized. Their enzymatic activities have not been demonstrated in or purified from any natural source. Using several selective DPP inhibitors, we show that DPP activity, attributable to DPP8/9 is present in human PBMC. All leukocyte types tested (lymphocytes, monocytes, Jurkat, and U937 cells) were shown to contain similar DPP8/9-specific activities, and DPPII- and DPPIV-specific activities varied considerably. The results were confirmed by DPPIV/CD26 immunocapture experiments. Subcellular fractionation localized the preponderance of DPP8/9 activity to the cytosol and DPPIV in the membrane fractions. Using Jurkat cell cytosol as a source, a 30-fold, enriched DPP preparation was obtained, which had enzymatic characteristics closely related to the ones of DPP8 and/or -9, including inhibition by allo-Ile-isoindoline and affinity for immobilized Lys-isoindoline.
Collapse
Affiliation(s)
- Marie-Berthe Maes
- Laboratory of Medical Biochemistry, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | | | | | | | | | | | | | | | | | | |
Collapse
|
26
|
Brandt I, Scharpé S, Lambeir AM. Suggested functions for prolyl oligopeptidase: a puzzling paradox. Clin Chim Acta 2006; 377:50-61. [PMID: 17034776 DOI: 10.1016/j.cca.2006.09.001] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [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: 08/02/2006] [Revised: 08/29/2006] [Accepted: 09/01/2006] [Indexed: 10/24/2022]
Abstract
Prolyl oligopeptidase (PO, E.C. 3.4.21.26) is a post-proline cleaving enzyme with endopeptidase activity towards peptides not longer than 30 amino acids. It has been purified and characterized from various mammalian and bacterial sources, but despite its thorough enzymological and structural characterization, the exact function of PO remains obscure. Many investigations have addressed the physiological role of this enzyme, mainly by the use of specific PO inhibitors, activity measurements in clinical samples and (neuro)peptide degradation studies. From the combined results emerges a puzzling paradox: how can an intracellular, cytoplasmatic oligopeptidase affect not only the amount of extracellular neuropeptides but also signal transduction and secretion? This report provides a review of the literature on the suggested functions for PO, highlighting possible pitfalls and contradictions.
Collapse
Affiliation(s)
- Inger Brandt
- Laboratory of Medical Biochemistry, Department of Pharmaceutical Sciences University of Antwerp, Universiteitsplein 1, Blg S6 B-2610 Antwerp (Wilrijk), Belgium
| | | | | |
Collapse
|
27
|
Blomqvist A, Berg C, Holm L, Brandt I, Ridderstråle Y, Brunström B. Defective Reproductive Organ Morphology and Function in Domestic Rooster Embryonically Exposed to o,p′-DDT or Ethynylestradiol1. Biol Reprod 2006; 74:481-6. [PMID: 16280416 DOI: 10.1095/biolreprod.105.045104] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [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: 11/01/2022] Open
Abstract
Environmental pollutants with estrogenic activity have a potential to disrupt estrogen-dependent developmental processes. The objective of this study was to investigate if embryonic exposure to the environmental estrogens o,p'-DDT (1-(2-chlorophenyl)-1-(4-chlorophenyl)-2,2,2-trichloroethane; 37, 75, 150 or 300 microg/g egg) and EE2 (17alpha-ethynyl estradiol; 60 ng/g egg) affects the reproductive system in domestic roosters. Following egg injection on Embryonic Day 4, the newly hatched chicks were sexed by cloacal inspection. A skewed phenotypic sex ratio with overrepresentation of chicks deemed as females was observed in the groups exposed to the three highest doses of o,p'-DDT but not in the EE2-exposed group. Normal sex ratios were observed in all groups at adulthood. However, a cloacal deformation seemed to remain in the adult roosters, causing an abnormal semen flow upon semen collection. Semen yield was significantly reduced in both o,p'-DDT-exposed and EE2- exposed birds, whereas semen quality was unaffected. When killed, deformations of the left testis were found in all treatment groups. Image analysis revealed a reduced seminiferous tubular area in the roosters exposed to the two highest doses of o,p'-DDT. Embryonic exposure to o,p'-DDT caused decreased comb weight and right-spur diameter, while EE2 only affected right-spur diameter. In conclusion, this study shows that embryonic exposure to estrogenic compounds can induce permanent effects in male birds. The effects of the two studied compounds were partly similar but o,p'-DDT also induced alterations not seen in the EE2-treated birds.
Collapse
Affiliation(s)
- A Blomqvist
- Department of Anatomy and Physiology, Swedish University of Agricultural Sciences, Centre for Reproductive Biology in Uppsala (CRU), 750 07 Uppsala, Sweden.
| | | | | | | | | | | |
Collapse
|
28
|
Affiliation(s)
- Inger Brandt
- Laboratory of Medical Biochemistry, Department of Pharmaceutical Sciences, University of Antwerp, Universiteitsplein 1, B-2610 Antwerp, Belgium
| | | | | | | | | |
Collapse
|
29
|
Brandt I, De Vriendt K, Devreese B, Van Beeumen J, Van Dongen W, Augustyns K, De Meester I, Scharpé S, Lambeir AM. Search for substrates for prolyl oligopeptidase in porcine brain. Peptides 2005; 26:2536-46. [PMID: 15996789 DOI: 10.1016/j.peptides.2005.05.016] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2005] [Revised: 05/23/2005] [Accepted: 05/23/2005] [Indexed: 11/17/2022]
Abstract
The function of prolyl oligopeptidase (PO) has been associated with several disorders of the central nervous system. The purpose of this study was to identify endogenous substrates for recombinant porcine PO in porcine brain. The smaller polypeptides were extracted from total brain homogenates and fractionated by two-dimensional chromatography prior to incubation with PO. Shifts in the mass spectrum between the control and the incubated sample, marked potential substrates. Using MSMS peptide sequencing techniques, we identified several fragments of intracellular proteins as potential substrates, which opens new perspectives for finding the function of PO in the intracellular space.
Collapse
Affiliation(s)
- Inger Brandt
- Laboratory of Medical Biochemistry, Department of Pharmaceutical Sciences, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Brandt I, Lambeir AM, Ketelslegers JM, Vanderheyden M, Scharpé S, De Meester I. Dipeptidyl-peptidase IV converts intact B-type natriuretic peptide into its des-SerPro form. Clin Chem 2005; 52:82-7. [PMID: 16254193 DOI: 10.1373/clinchem.2005.057638] [Citation(s) in RCA: 147] [Impact Index Per Article: 7.7] [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: 01/16/2023]
Abstract
BACKGROUND Analysis of plasma B-type natriuretic peptide (BNP) has suggested the in vivo formation of a truncated form, BNP (3-32), also called des-SerPro-BNP. The objectives of this study were to investigate (a) whether BNP and other natriuretic peptides are truncated by dipeptidyl-peptidase IV (DPP IV/CD26; EC 3.4.14.5) and (b) whether this truncation affects the susceptibility to cleavage by neutral endopeptidase (NEP; EC 3.4.24.11). METHODS Human BNP (1-32), A-type natriuretic peptide 1-28 (ANP 1-28), and related peptides were incubated with purified DPP IV and with human plasma. In addition, BNP (1-32), BNP (3-32), and ANP (1-28) were subjected to hydrolysis by NEP. Cleavage products were analyzed by mass spectrometry. RESULTS BNP (1-32) was cleaved by purified DPP IV with a specificity constant of 0.37 x 10(6) L.mol(-1).s(-1). The DPP IV activity in EDTA-plasma was able to truncate BNP (1-32) ex vivo. Addition of Vildagliptin, a specific DPP IV inhibitor, prevented this truncation in a concentration-dependent manner. Under in vitro circumstances in which ANP was hydrolyzed extensively, BNP (1-32) and BNP (3-32) were very resistant to NEP-mediated cleavage. CONCLUSIONS DPP IV cleaves BNP (1-32) with an efficiency higher than or comparable to several known in vivo substrates of the enzyme. Even after loss of the amino-terminal dipeptide, BNP remains highly resistant to cleavage by NEP.
Collapse
Affiliation(s)
- Inger Brandt
- Laboratory of Medical Biochemistry, Department of Pharmaceutical Sciences, University of Antwerp, Antwerp, Belgium
| | | | | | | | | | | |
Collapse
|
31
|
Brandt I, Joossens J, Chen X, Maes MB, Scharpé S, De Meester I, Lambeir AM. Inhibition of dipeptidyl-peptidase IV catalyzed peptide truncation by Vildagliptin ((2S)-{[(3-hydroxyadamantan-1-yl)amino]acetyl}-pyrrolidine-2-carbonitrile). Biochem Pharmacol 2005; 70:134-43. [PMID: 15907807 DOI: 10.1016/j.bcp.2005.04.009] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2005] [Revised: 04/13/2005] [Accepted: 04/14/2005] [Indexed: 12/20/2022]
Abstract
Vildagliptin (NVP-LAF237/(2S)-{[(3-hydroxyadamantan-1-yl)amino]acetyl}-pyrrolidine-2-carbonitrile) was described as a potent, selective and orally bio-available dipeptidyl-peptidase IV (DPP IV, EC 3.4.14.5) inhibitor [Villhauer EB, Brinkman JA, Naderi GB, Burkey BF, Dunning BE, Prasad K, et al.1-[[(3-Hydroxy-1-adamantyl)amino]acetyl]-2-cyano-(S)-pyrrolidine: a potent, selective, and orally bioavailable dipeptidyl peptidase IV inhibitor with antihyperglycemic properties. J Med Chem 2003;46:2774-89]. Phase III clinical trials for the use of this compound in the treatment of Type 2 diabetes were started in the first quarter of 2004. In this paper, we report on (1) the kinetics of binding, (2) the type of inhibition, (3) the selectivity with respect to other peptidases, and (4) the inhibitory potency on the DPP IV catalyzed degradation of glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP) and substance P. Vildagliptin behaved as a slow-binding DPP IV inhibitor with an association rate constant of 1.4x10(5)M(-1)s(-1) and a K(i) of 17nM. It is a micromolar inhibitor for dipeptidyl-peptidase 8 and does not significantly inhibit dipeptidyl-peptidase II (EC 3.4.11.2), prolyl oligopeptidase (EC 3.4.21.26), aminopeptidase P (EC 3.4.11.9) or aminopeptidase M (EC 3.4.11.2). There was no evidence for substrate specific inhibition of DPP IV by Vildagliptin or for important allosteric factors affecting the inhibition constant in presence of GIP and GLP-1.
Collapse
Affiliation(s)
- Inger Brandt
- Laboratory of Medical Biochemistry, Department of Pharmaceutical Sciences, University of Antwerp, Drie Eiken Campus, Universiteitsplein 1 building S6 B-2610 Antwerpen (Wilrijk), Belgium
| | | | | | | | | | | | | |
Collapse
|
32
|
Berg C, Blomqvist A, Holm L, Brandt I, Brunström B, Ridderstråle Y. Embryonic exposure to oestrogen causes eggshell thinning and altered shell gland carbonic anhydrase expression in the domestic hen. Reproduction 2004; 128:455-61. [PMID: 15454640 DOI: 10.1530/rep.1.00211] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [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: 11/08/2022]
Abstract
Eggshell thinning among wild birds has been an environmental concern for almost half a century. Although the mechanisms for contaminant-induced eggshell thinning are not fully understood, it is generally conceived to originate from exposure of the laying adult female. Here we show that eggshell thinning in the domestic hen is induced by embryonic exposure to the synthetic oestrogen ethynyloestradiol. Previously we reported that exposure of quail embryos to ethynyloestradiol caused histological changes and disrupted localization of carbonic anhydrase in the shell gland in the adult birds, implying a functional disturbance in the shell gland. The objective of this study was to examine whether in ovo exposure to ethynyloestradiol can affect eggshell formation and quality in the domestic hen. When examined at 32 weeks of age, hens exposed to ethynyloestradiol in ovo (20 ng/g egg) produced eggs with thinner eggshells and reduced strength (measured as resistance to deformation) compared with the controls. These changes remained 14 weeks later, confirming a persistent lesion. Ethynyloestradiol also caused a decrease in the number of shell gland capillaries and in the frequency of shell gland capillaries with carbonic anhydrase activity. These data suggested that a disrupted carbonic anhydrase expression was involved in the mechanism for the oestrogen-induced eggshell thinning found in this study. The results support our hypothesis that eggshell thinning in avian wildlife can result from a structural and functional malformation in the shell gland, induced by xeno-oestrogen exposure during embryonic development.
Collapse
Affiliation(s)
- C Berg
- Department of Environmental Toxicology, Uppsala University, Norbyvägen 18 A, 753 36 Uppsala, Sweden.
| | | | | | | | | | | |
Collapse
|
33
|
Carlsson C, Harju M, Bahrami F, Cantillana T, Tysklind M, Brandt I. 170 Olfactory mucosal toxicity screening and multivariate QSAR modelling for chlorinated benzene derivatives. Toxicol Lett 2003. [DOI: 10.1016/s0378-4274(03)90169-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
34
|
Lindhe O, Granberg L, Brandt I. Cytochrome P450-catalysed irreversible binding examined in precision-cut adrenal slice culture. Adv Exp Med Biol 2002; 500:531-4. [PMID: 11764994 DOI: 10.1007/978-1-4615-0667-6_81] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Affiliation(s)
- O Lindhe
- Dept of Environmental Toxicology, EBC, Uppsala University, Sweden.
| | | | | |
Collapse
|
35
|
Halldin K, Berg C, Bergman A, Brandt I, Brunström B. Distribution of bisphenol A and tetrabromobisphenol A in quail eggs, embryos and laying birds and studies on reproduction variables in adults following in ovo exposure. Arch Toxicol 2001; 75:597-603. [PMID: 11808920 DOI: 10.1007/s002040100277] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [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: 10/27/2022]
Abstract
In a previous study, we showed that bisphenol A (BPA) had oestrogen-like effects in bird embryos, causing malformations of the oviducts in Japanese quail (Coturnix japonica) and feminisation of the left testis in chicken (Gallus domesticus). In this study, uptake and distribution of BPA and tetrabromobisphenol A (TBBPA) in embryos and laying quail were examined as well as variables related to reproduction in adult quail following administration of the compounds into the yolk of embryonated eggs. The uptake of radiolabelled BPA, TBBPA and the reference compound diethylstilboestrol (DES) was studied in the embryos using beta-spectrometry. Autoradiography was employed to examine distribution in egg and embryo after yolk sac injection of BPA or TBBPA and in laying birds, following intravenous and oral administration. Following embryonic exposure to BPA or TBBPA, sexually mature male birds were examined for reproductive behaviour and testis morphology, and females were examined for egg laying and oviduct morphology. Neither BPA (200 microg/g egg) nor TBBPA (15 microg/g egg) caused any significant oestrogen-like effects on the variables studied, although effects on the female oviducts after BPA exposure were indicated. Embryonic exposure to DES is known to cause profound effects on male sexual behaviour and female oviduct morphology at doses 3-5 orders of magnitude lower than the BPA and TBBPA doses used in the present study. The proportions of BPA and TBBPA taken up by the embryos after yolk sac injection were similar to the proportion of DES taken up. Differences in bioavailability, therefore do not account for any major part of the potency differences between DES and the two bisphenol A compounds. The concentration of radioactivity in the embryo, as revealed by autoradiography, was low compared with that in the yolk at all stages studied (days 6, 10 and 15). Pronounced labelling of the bile and the allantoic fluid was observed, however, indicating that both compounds were readily metabolised and excreted. Radiolabelled BPA and TBBPA administered to laying quail were largely excreted via the bile and 9 days after oral dosing, only small amounts of the labelled compound remained within the body. Maternal transfer of labelled BPA and TBBPA to the egg was low.
Collapse
Affiliation(s)
- K Halldin
- Department of Environmental Toxicology, Evolutionary Biology Centre, Uppsala University, Sweden.
| | | | | | | | | |
Collapse
|
36
|
Holm L, Berg C, Brunström B, Ridderstråle Y, Brandt I. Disrupted carbonic anhydrase distribution in the avian shell gland following in ovo exposure to estrogen. Arch Toxicol 2001; 75:362-8. [PMID: 11570694 DOI: 10.1007/s002040100241] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [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: 10/27/2022]
Abstract
Eggshell thinning among wild birds has been an environmental concern for almost half a century and the underlying mechanisms are still not fully understood. Previously we showed that exposure of quail embryos to ethynylestradiol (EE2) caused disorganization of the tubular glands in the shell gland of adult birds. In this study, we have examined the effect of in ovo exposure to EE2 on carbonic anhydrase (CA) localization, especially in the shell gland, because CA is required for shell formation. In the control birds, CA was localized in the cell membranes of the tubular gland cells of the shell gland, whereas the surface epithelium was always devoid of CA. In ovo treatment with 20ng EE2/g egg resulted in a loss of CA activity in the tubular glands while the surface epithelium showed strong induction of both membrane bound and cytoplasmic CA activity in 49+/-1% of the cells. The dose 2ng EE2/g egg resulted in partial loss of tubular gland CA and strong induction of CA activity in 2.5+/-0.5% of the surface epithelial cells and weaker induction in 22+/-2% of the epithelial cells. In conclusion, this study shows that embryonic exposure to a xenoestrogen disrupts CA distribution in the adult shell gland. We propose that eggshell thinning in avian wildlife could reflect a functional malformation in the shell gland, already induced by xenoestrogen during embryonic development rather than being caused solely by exposure of the adult bird.
Collapse
Affiliation(s)
- L Holm
- Department of Animal Physiology, Center for Reproductive Biology in Uppsala, Swedish University of Agricultural Sciences.
| | | | | | | | | |
Collapse
|
37
|
Lindhe O, Lund BO, Bergman A, Brandt I. Irreversible binding and adrenocorticolytic activity of the DDT metabolite 3-methylsulfonyl-DDE examined in tissue-slice culture. Environ Health Perspect 2001; 109:105-110. [PMID: 11266318 PMCID: PMC1240628 DOI: 10.1289/ehp.109-1240628] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The persistent adrenocorticolytic DDT metabolite 3-methylsulfonyl-DDE (MeSO(2)-DDE) was originally identified in Baltic grey seals, a population suffering from adrenocortical hyperplasia. In mice, MeSO(2)-DDE induces mitochondrial degeneration and cellular necrosis in the adrenal zona fasciculata. In this study, we used precision-cut tissue slice culture to examine local CYP11B1-catalyzed irreversible binding of MeSO(2)-DDE in the murine adrenal cortex. We also examined effects on steroid hormone secretion, histology, and ultrastructure. As determined by microautoradiography, selective binding occurred in zona fasciculata of slices exposed to MeSO(2)-[(14)C]-DDE. Quantification of binding by phosphorautoradiography revealed a 3-fold reduction of binding in slices co-exposed to the CYP11B1 inhibitor metyrapone. As measured by HPLC, corticosterone and 11-deoxycorticosterone secretion to the medium increased linearly for at least 24 hr. Addition of the ACTH analog tetracosactide caused an 8-fold increase in corticosterone secretion. Addition of metyrapone reduced corticosterone secretion 4-fold. Exposure of slices to MeSO(2)-DDE (50 microM) reduced the rate of corticosterone secretion by 90% after 24 hr of incubation. As determined by electron microscopy, vacuolated mitochondria were present in zona fasciculata of slices exposed to MeSO(2)-DDE (50 microM) for 24 hr. Our findings show that all effects of MeSO(2)-DDE previously reported in vivo could be reproduced in adrenal slice culture ex vivo. This test system allows analysis of zone-specific irreversible binding and effects on steroid hormone secretion and target cell ultrastructure. We propose adrenal slice culture as a simple ex vivo test system with which to examine the adrenocorticolytic activity of xenobiotics in human and wild animal tissue.
Collapse
Affiliation(s)
- O Lindhe
- Department of Environmental Toxicology, Uppsala University, Uppsala, Sweden
| | | | | | | |
Collapse
|
38
|
Berg C, Holm L, Brandt I, Brunström B. Anatomical and histological changes in the oviducts of Japanese quail, Coturnix japonica, after embryonic exposure to ethynyloestradiol. Reproduction 2001; 121:155-65. [PMID: 11226039 DOI: 10.1530/rep.0.1210155] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.0] [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: 11/08/2022]
Abstract
Oestrogen is needed for normal oviductal development in female birds, but excessive early exposure to oestrogen can cause oviductal abnormalities and impair egg-laying ability. In this study, the anatomical and histological effects of in ovo exposure to the synthetic oestrogen ethynyloestradiol on the oviducts of immature and adult female Japanese quail, Coturnix japonica, were investigated. A series of abnormalities was observed after injection of ethynyloestradiol (2 or 20 ng g(-1) egg) into the yolk on day 3 of incubation. Ethynyloestradiol induced precocious differentiation of the luminal epithelium and tubular glands in immature chicks. Right-side oviduct retention occurred at all the ages studied, whereas certain other effects were not evident until sexual maturity. The left oviduct was reduced in size and tubular gland density in the uterus (shell gland) was reduced in sexually mature birds that had been treated with ethynyloestradiol. The utero-vaginal junction was longer than in control birds and had a higher tubular gland density. The epithelial cells in the magnum were taller in birds treated with ethynyloestradiol. Embryonic exposure to the environmental contaminant ethynyloestradiol may cause persisting structural malformations in oviducts of quails, which can impair fertility. As oviductal malformations are indicative of embryonic exposure to exogenous oestrogen, they are potentially useful as biomarkers of xenooestrogen exposure in wild bird populations.
Collapse
Affiliation(s)
- C Berg
- Department of Environmental Toxicology, Centre for Reproductive Biology in Uppsala, Uppsala University, Norbyvägen 18 A, SE-752 36 Uppsala, Sweden.
| | | | | | | |
Collapse
|
39
|
Granberg AL, Brunström B, Brandt I. Cytochrome P450-dependent binding of 7,12-dimethylbenz[a]anthracene (DMBA) and benzo[a]pyrene (B[a]P) in murine heart, lung, and liver endothelial cells. Arch Toxicol 2000; 74:593-601. [PMID: 11201666 DOI: 10.1007/s002040000171] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [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: 10/27/2022]
Abstract
Autoradiography was used to investigate the cellular sites of irreversible binding of 3H-labelled 7,12-dimethylbenz[a]anthracene (DMBA) and benzo[a]pyrene (B[a]P) in mice. Autoradiograms obtained from solvent-extracted tape-sections revealed an even distribution of DMBA- and B[a]P-derived radioactivity in control mice lacking sites of selective binding in the tissues. In mice pretreated with a cytochrome P4501A (CYP1A) inducer, beta-naphthoflavone (BNF) or 3,3',4,4', 5-pentachlorobiphenyl (PCB 126), a noticeable accumulation of bound radioactivity was observed in the pulmonary alveolar region. Increased labelling was also observed in heart tissue of induced mice. As demonstrated by microautoradiography of tissues from CYP1A-induced mice treated with 3H-DMBA or 3H-B[a]P in vivo, irreversible binding in lung tissue was present in endothelial cells of arteries and veins, in the alveolar septal walls, and in type 2 pneumocytes. In heart tissue, binding was confined to endothelial cells of arteries, capillaries and veins. In liver, binding was found in the hepatocytes as well as in endothelial cells of the portal veins, whereas no binding was seen in endothelial cells of the sinusoids, central veins, or arteries. These findings were confirmed in vitro using 3H-DMBA-exposed precision-cut slices, indicating that reactive intermediates of DMBA and B(a)P were formed in situ. The addition of the CYP1A inhibitor ellipticine abolished binding in the target endothelial cells. Increased endothelial binding in the lungs and liver of CYP1A-induced mice was concomitant with increased 7-ethoxyresorufin O-deethylase (EROD) and DMBA hydroxylase activity. In heart, endothelial binding was positively correlated with EROD, but not with DMBA hydroxylase. The results suggest that endothelial cells may be targets for CYP-dependent activation of such toxicants as polycyclic aromatic hydrocarbons. Consequently, the possibility that chemically induced endothelial dysfunction is a risk factor in the aetiology of cardiovascular disease demands consideration.
Collapse
Affiliation(s)
- A L Granberg
- Department of Environmental Toxicology, Evolutionary Biology Centre, Uppsala University, Sweden
| | | | | |
Collapse
|
40
|
Abstract
Previously we reported that methylsulphonyl-2,6-dichlorobenzene, 2, 6-(diCl-MeSO(2)-B), was irreversibly bound to the olfactory mucosa of mice and induced necrosis of the Bowman's glands with subsequent neuroepithelial degeneration and detachment. In this study, autoradiography and histopathology were used to determine tissue-localization and toxicity of 2,6-(diCl-MeSO(2)-B) in the olfactory mucosa of control mice and animals pretreated with cytochrome P450 (CYP) and glutathione (GSH) modulators. The Bowman's glands of the olfactory mucosa were the major target sites of non-extractable binding of 2,6-(diCl-(14)C-MeSO(2)-B), whereas the olfactory neuroepithelium and nerve bundles showed only background levels of silver grains. Metyrapone pretreatment slightly decreased binding in the Bowman's glands and markedly decreased toxicity in the olfactory mucosa after 2,6-(diCl-MeSO(2)-B) administration. These results support that a CYP-mediated activation of 2, 6-(diCl-MeSO(2)-B) takes place in the Bowman's glands giving rise to toxic reactive intermediates. In mice pretreated with the GSH-depleting agent phorone, a marked increase of irreversible binding of 2,6-(diCl-(14)C-MeSO(2)-B) in the Bowman's glands was observed. Tape-section autoradiograms also revealed a significant increase of uptake of radioactivity in the olfactory bulb. As determined by histopathology, GSH-depletion increased both the extent and severity of the lesion in the mucosa. These results imply that 2,6-(diCl-MeSO(2)-B)-reactive intermediates are conjugated with GSH. The amount of irreversible binding and toxicity in the olfactory mucosa seems to be associated with the level of 2, 6-(diCl-MeSO(2)-B)-reactive intermediates.
Collapse
Affiliation(s)
- F Bahrami
- Department of Environmental Toxicology, Uppsala University, Norbyvägen 18A, S-752 36, Uppsala, Sweden
| | | | | | | |
Collapse
|
41
|
Abstract
OBJECTIVE AND METHODS In the Bonn Longitudinal Study (BLS), the course of neurologic development was analysed with regard to transient abnormal neurologic signs (TANS). Abnormal neurologic signs (ANS) are defined when present in at least one developmental area at one examination. From birth to adulthood (mean 23 years) 108 preterm infants, 81% of very low birth weight (VLBW) were examined with regard to their psychological, neurologic and physical development: 62 appropriate for gestational age (AGA), 46 small for gestational age (SGA), 27 with postnatal catch-up growth of head circumference (group A) and 19 without catch-up (group B); 73 full terms served as controls. The dropout rate was 7.6%. RESULTS ANS showed a great inter- and intraindividual variability. Episodes of neurologic abnormalities changed with those of normality. ANS reappeared when new abilities developed. ANS were observed mainly during the first year. The incidence was higher in preterms (AGA 49%, SGA A 63%, SGA B 61%) than in full terms (15%). Transient ANS (TANS) were diagnosed in 42% of AGA, 63% of SGA A, 33% of SGA B preterms and 12% of full terms. The recovery rate, i.e., the TANS to ANS percentage, was higher in AGA (86%), SGA A (100%) and full terms (82%) than in SGA B (55%) preterms. CONCLUSION It is impossible to predict early on whether ANS will be transient, i.e. TANS. Longitudinal analyses are needed. The outcome depends on recovery from or persistence in ANS.
Collapse
Affiliation(s)
- I Brandt
- Developmental Paediatrics, Department of Paediatrics, Children's Hospital, Medical Centre, University of Bonn, Adenauerallee 119, D-53113, Bonn, Germany.
| | | | | | | |
Collapse
|
42
|
Bahrami F, Bergman U, Brittebo EB, Brandt I. Persistent olfactory mucosal metaplasia and increased olfactory bulb glial fibrillary acidic protein levels following a single dose of methylsulfonyl-dichlorobenzene in mice: comparison of the 2,5- and 2, 6-dichlorinated isomers. Toxicol Appl Pharmacol 2000; 162:49-59. [PMID: 10631127 DOI: 10.1006/taap.1999.8818] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [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]
Abstract
Histopathology was used to characterize long-term toxic effects in the olfactory system following a single ip dose (4-65 mg/kg) of methylsulfonyl-2,6-dichlorobenzene, (2,6-(diCl-MeSO(2)-B)), in female NMRI mice. The effects of 2,6-(diCl-MeSO(2)-B) and its 2, 5-chlorinated isomer, (2,5-(diCl-MeSO(2)-B)), on the levels of glial fibrillary acidic protein (GFAP; a biomarker for neurotoxicity) in different brain regions were examined by an enzyme-linked immunosorbent assay (ELISA). The histopathologic effects of 2, 6-(diCl-MeSO(2)-B) were dose-, time-, and tissue-dependent. At the highest doses (16-65 mg/kg), the initial effect of 2, 6-(diCl-MeSO(2)-B) was necrosis of the Bowman's glands, followed by a sequence of secondary events including degeneration of the olfactory neuroepithelium, repopulation of the basement membrane by a ciliated respiratorylike epithelium, fibrosis and ossification in the lamina propria, formation of bilateral polyps, angiogenesis, and disappearance of nerve bundles. Remodeling was most pronounced in the dorsal meatus of the olfactory mucosa and persisted for the duration of the experiment (46 weeks). A dose-dependent induction of GFAP in the olfactory bulb of mice treated with 2,6-(diCl-MeSO(2)-B) was observed at all doses examined (16-65 mg/kg). GFAP levels were highest 2 weeks after treatment (eightfold induction at 65 mg/kg) and then gradually decreased to normal within 26 weeks. The 2, 5-substituted isomer (65 mg/kg) did not induce GFAP in the olfactory bulb and or toxicity in the olfactory mucosa. In conclusion, a single dose of 2,6-(diCl-MeSO(2)-B) results in persistent metaplasia and remodeling of the olfactory mucosa, and a long-lasting but transient induction of GFAP in the olfactory bulb. It is proposed that methylsulfonyl-2,6-dichlorobenzene may serve as an experimental tool with a unique ability to produce persistent primary and/or secondary lesions in the olfactory system of mice.
Collapse
Affiliation(s)
- F Bahrami
- Department of Environmental Toxicology, Evolutionary Biology Center, Uppsala University, Norbyvägen 18C, Uppsala, S-752 36, Sweden
| | | | | | | |
Collapse
|
43
|
Vos JG, Dybing E, Greim HA, Ladefoged O, Lambré C, Tarazona JV, Brandt I, Vethaak AD. Health effects of endocrine-disrupting chemicals on wildlife, with special reference to the European situation. Crit Rev Toxicol 2000; 30:71-133. [PMID: 10680769 DOI: 10.1080/10408440091159176] [Citation(s) in RCA: 439] [Impact Index Per Article: 18.3] [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: 10/25/2022]
Abstract
Many wildlife species may be exposed to biologically active concentrations of endocrine-disrupting chemicals. There is strong evidence obtained from laboratory studies showing the potential of several environmental chemicals to cause endocrine disruption at environmentally realistic exposure levels. In wildlife populations, associations have been reported between reproductive and developmental effects and endocrine-disrupting chemicals. In the aquatic environment, effects have been observed in mammals, birds, reptiles, fish, and mollusks from Europe, North America, and other areas. The observed abnormalities vary from subtle changes to permanent alterations, including disturbed sex differentiation with feminized or masculinized sex organs, changed sexual behavior, and altered immune function. For most reported effects in wildlife, however, the evidence for a causal link with endocrine disruption is weak or nonexisting. Crucial in establishing causal evidence for chemical-induced wildlife effects appeared semifield or laboratory studies using the wildlife species of concern. Impaired reproduction and development causally linked to endocrine-disrupting chemicals are well documented in a number of species and have resulted in local or regional population changes. These include: Masculinization (imposex) in female marine snails by tributyltin, a biocide used in antifouling paints, is probably the clearest case of endocrine disruption caused by an environmental chemical. The dogwhelk is particularly sensitive, and imposex has resulted in decline or extinction of local populations worldwide, including coastal areas all over Europe and the open North Sea. DDE-induced egg-shell thinning in birds has caused severe population declines in a number of raptor species in Europe and North America. Endocrine-disrupting chemicals have adversely affected a variety of fish species. In the vicinity of certain sources (e.g., effluents of water treatment plants) and in the most contaminated areas is this exposure causally linked with the effects on reproductive organs that could have implications for fish populations. However, there is also a more widespread occurrence of endocrine disruption in fish in the U.K., where estrogenic effects have been demonstrated in freshwater systems, in estuaries, and in coastal areas. In mammals, the best evidence comes from the-field studies on Baltic gray and ringed seals, and from the Dutch semifield studies on harbor seals, where both reproduction and immune functions have been impaired by PCBs in the food chain. Reproduction effects resulted in population declines, whereas impaired immune function has likely contributed to the mass mortalities due to morbillivirus infections. Distorted sex organ development and function in alligators has been related to a major pesticide spill into a lake in Florida, U.S.A. The observed estrogenic/antiandrogenic effects in this reptile have been causally linked in experimental studies with alligator eggs to the DDT complex. Although most observed effects currently reported concern heavily polluted areas, endocrine disruption is a potential global problem. This is exemplified by the widespread occurrence of imposex in marine snails and the recent findings of high levels of persistent potential endocrine-disrupting chemicals in several marine mammalian species inhabiting oceanic waters.
Collapse
Affiliation(s)
- J G Vos
- National Institute of Public Health and the Environment, Bilthoven, The Netherlands
| | | | | | | | | | | | | | | |
Collapse
|
44
|
Annas A, Granberg L, Strandberg W, Brandt I, Brittebo EB, Brunström B. Basal and induced EROD activity in the chorioallantoic membrane during chicken embryo development. Environ Toxicol Pharmacol 1999; 8:49-52. [PMID: 21781941 DOI: 10.1016/s1382-6689(99)00030-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/1999] [Revised: 08/14/1999] [Accepted: 09/03/1999] [Indexed: 05/31/2023]
Abstract
The chorioallantoic membrane (CAM) is a highly vascularized tissue that takes part in the respiratory exchange of gases through the eggshell. Although the CAM may be exposed to environmental contaminants, its response to pollutants has not been studied. We examined the cytochrome P4501A (CYP1A)-catalyzed deethylation of 7-ethoxyresorufin (EROD) in the CAM during chicken embryo development. EROD was constitutively present and was inducible by the aryl hydrocarbon (Ah) receptor agonist 3,3',4,4',5-pentachlorobiphenyl (PCB 126). Our results suggest the CAM as a first line of defence of the avian embryo against toxic compounds, but also as a target for CYP1A-activated chemicals.
Collapse
Affiliation(s)
- A Annas
- Department of Pharmaceutical Biosciences, Division of Toxicology, Uppsala University, Box 594, SE-751 24 Uppsala, Sweden
| | | | | | | | | | | |
Collapse
|
45
|
Halldin K, Berg C, Brandt I, Brunström B. Sexual behavior in Japanese quail as a test end point for endocrine disruption: effects of in ovo exposure to ethinylestradiol and diethylstilbestrol. Environ Health Perspect 1999; 107:861-6. [PMID: 10544152 PMCID: PMC1566711 DOI: 10.1289/ehp.99107861] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Chemicals having a capacity to disturb the endocrine system have attracted considerable interest during recent years. There is a shortage of well-characterized in vivo tests with which to study such disturbances in different classes of vertebrates. In the present study, test end points related to reproduction in the Japanese quail were used to examine the estrogenic activity of chemicals. The synthetic estrogens ethinylestradiol (EE(2)) and diethylstilbestrol (DES), used as model compounds, were injected into the yolk of embryonated eggs. After the birds had been raised to sexual maturity, we examined sexual behavior, plasma testosterone concentrations, and testis morphology in adult males. The lowest doses resulting in a significantly depressed male sexual behavior were 6 ng/g egg for EE(2) and 19 ng/g egg for DES. Testis weight asymmetry was increased at 6 ng EE(2)/g egg, but DES had no effect at any treatment level. The area of the androgen-dependent cloacal gland was significantly reduced at 57 ng DES/g egg. No effects on plasma testosterone concentration or body weight following exposure to EE(2) or DES were observed at any dose level. Depressed male sexual behavior was the most sensitive of the end points studied, and we suggest that this ecologically relevant end point be included in avian in vivo testing for neuroendocrine disruptors.
Collapse
Affiliation(s)
- K Halldin
- Department of Environmental Toxicology, Uppsala University, Uppsala, Sweden.
| | | | | | | |
Collapse
|
46
|
Berg C, Halldin K, Fridolfsson AK, Brandt I, Brunström B. The avian egg as a test system for endocrine disrupters: effects of diethylstilbestrol and ethynylestradiol on sex organ development. Sci Total Environ 1999; 233:57-66. [PMID: 10492898 DOI: 10.1016/s0048-9697(99)00179-5] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
Abstract
Many environmental contaminants are known or suspected to interfere with hormonal function in animals. In vivo test methods to detect and characterize chemicals that disrupt the endocrine system are therefore urgently needed. In this study, we assessed the usefulness of abnormalities of the reproductive organs as test endpoints for estrogenic activity of xenobiotics in Japanese quail embryos. Two synthetic estrogens, diethylstilbestrol (DES) and ethynylestradiol (EE2), were injected into the yolks of embryonated eggs. At a dose as low as 2 ng EE2/g egg, all male embryos became feminized, containing ovary-like tissue in the left testis. The extent of feminization of the testes was determined by measuring the relative area of the ovary-like component. Persistent Müllerian ducts (oviducts) in male embryos, and malformations of the Müllerian ducts in females occurred at 2 ng EE2/g egg and higher doses. DES was approximately one-third to one-tenth as potent as EE2. The morphological changes studied were dose-dependent, indicating that they are useful as test endpoints for estrogenic activity. Feminization of the left testis in males proved to be the most sensitive endpoint. We propose the quail egg as a simple in vivo test system for estrogenic compounds.
Collapse
Affiliation(s)
- C Berg
- Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences, Uppsala Biomedical Centre, Sweden
| | | | | | | | | |
Collapse
|
47
|
Bahrami F, Brittebo EB, Bergman A, Larsson C, Brandt I. Localization and comparative toxicity of methylsulfonyl-2,5- and 2,6-dichlorobenzene in the olfactory mucosa of mice. Toxicol Sci 1999; 49:116-23. [PMID: 10367349 DOI: 10.1093/toxsci/49.1.116] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [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: 11/14/2022] Open
Abstract
Several methylsulfonyl (MeSO2) metabolites formed from chlorinated aromatic hydrocarbons have been identified in human milk, lung, and body fat, as well as in the tissues of Baltic grey seals and arctic polar bears. The tissue localization and nasal toxicity of two methylsulfonyl-substituted dichlorobenzenes (diCl-MeSO2-B), with the chlorine atoms in the 2,5-, and 2,6- positions, were investigated in female NMRI and C57B1 mice. Using tape-section autoradiography, animals dosed i.v. with 14C-labeled 2,5-, or 2,6-(diCl-MeSO2-B) showed a preferential uptake of radioactivity in the olfactory mucosa and the tracheobronchial epithelium. Histopathology showed that 2,6-(diCl-MeSO2-B) is a potent toxicant that induces necrosis in the olfactory mucosa following a single dose as low as 4 mg/kg (i.p. injection), whereas 2,5-(diCl-MeSO2-B) induced no signs of toxicity in the olfactory mucosa at doses as high as 130 mg/kg (i.p. injection). Necrosis of the Bowman's glands was the first sign of 2,6-(diCl-MeSO2-B)-induced toxicity followed by degeneration of the neuroepithelium, which implies that the Bowman's gland may be the primary site of toxicity and degeneration of the neuroepithelium may be a secondary effect. Administration of the parent compounds, 1,3-dichlorobenzene and 1,4-dichlorobenzene, or the chlorinated analog 1,2,3-trichlorobenzene (85, 85, and 105 mg/kg, respectively; i.p. injection), induced no signs of toxicity in the olfactory mucosa. These and previous results suggest that 2,6-positioned chlorine atoms and an electron withdrawing substituent in the primary position is an arrangement that predisposes for toxicity in the olfactory mucosa.
Collapse
Affiliation(s)
- F Bahrami
- Department of Environmental Toxicology, Uppsala University, Sweden
| | | | | | | | | |
Collapse
|
48
|
Abstract
The embryonated bird egg provides a simple whole organism test system that allows examination of xenoestrogenic effects at different levels of biological organisation. Test compounds are injected into the yolk, the albumen or the air chamber at defined stages of embryonic development. Bioavailability and embryonic exposure may be determined by autoradiography and image analysis. Females represent the heterogametic sex (ZW) and estrogens determine differentiation into the female phenotype in birds. Xenoestrogenic effects can be examined by markers of gene expression and anatomical or histological characterization of the gonads and tubular sex organs. Chicks may be raised to sexual maturity and examination of sexual behaviour and reproductive physiology performed. The Japanese quail is a suitable test organism due to its small size and early sexual maturation.
Collapse
Affiliation(s)
- C Berg
- Department of Environmental Toxicology, Uppsala University, Sweden
| | | | | | | |
Collapse
|
49
|
Vallack HW, Bakker DJ, Brandt I, Broström-Lundén E, Brouwer A, Bull KR, Gough C, Guardans R, Holoubek I, Jansson B, Koch R, Kuylenstierna J, Lecloux A, Mackay D, McCutcheon P, Mocarelli P, Taalman RD. Controlling persistent organic pollutants-what next? Environ Toxicol Pharmacol 1998; 6:143-75. [PMID: 21781891 DOI: 10.1016/s1382-6689(98)00036-2] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 09/07/1998] [Indexed: 05/23/2023]
Abstract
Within the context of current international initiatives on the control of persistent organic pollutants (POPs), an overview is given of the scientific knowledge relating to POP sources, emissions, transport, fate and effects. At the regional scale, improvements in mass balance models for well-characterised POPs are resulting in an ability to estimate their environmental concentrations with sufficient accuracy to be of help for some regulatory purposes. The relevance of the parameters used to define POPs within these international initiatives is considered with an emphasis on mechanisms for adding new substances to the initial lists. A tiered approach is proposed for screening the large number of untested chemical substances according to their long-range transport potential, persistence and bioaccumulative potential prior to more detailed risk assessments. The importance of testing candidate POPs for chronic toxicity (i.e. for immunotoxicity, endocrine disruption and carcinogenicity) is emphasised as is a need for the further development of relevant SAR (structure activity relationship) models and in vitro and in vivo tests for these effects. Where there is a high level of uncertainty at the risk assessment stage, decision-makers may have to rely on expert judgement and weight-of-evidence, taking into account the precautionary principle and the views of relevant stake-holders. Close co-operation between the various international initiatives on POPs will be required to ensure that assessment criteria and procedures are as compatible as possible.
Collapse
Affiliation(s)
- H W Vallack
- Stockholm Environment Institute at York, University of York, York, United Kingdom
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
50
|
Halldin K, Berg C, Brandt I, Brunström B. Altered sexual behavior in the Japanese quail as an endpoint for endocrine disruption. Toxicol Lett 1998. [DOI: 10.1016/s0378-4274(98)80277-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|