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Geißer D, Hetzel L, Westenfeld R, Boege F. Questionable Validity of Creatinine-Based eGFR in Elderly Patients but Cystatin C Is Helpful in First-Line Diagnostics. Geriatrics (Basel) 2023; 8:120. [PMID: 38132491 PMCID: PMC10742602 DOI: 10.3390/geriatrics8060120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 12/01/2023] [Accepted: 12/04/2023] [Indexed: 12/23/2023] Open
Abstract
BACKGROUND The recommended chronic kidney disease (CKD) first-line diagnostic test is based on the creatinine-derived (estimated) glomerular filtration rate (eGFR). Cystatin C use may provide a better assessment. METHODS We compared creatinine- and cystatin C-derived eGFR determination as the first-line diagnostic test for 112 hospital patients aged > 60 years (median = 76 years). The patients were judged to not have CKD (no-CKD group) according to the first-line diagnostic recommendations (n = 61, eGFR (CKD Epidemiology Collaboration (CKD-EPI)) ≥ 60 mL/min/1.73 m2, total urine protein < 150 mg/g creatinine, urinary red/white blood cells not increased) or classified to be at risk for kidney insufficiency due to aortic valve dysfunction (at-risk group; n = 51). The accuracy of the eGFR values was evaluated retrospectively with the final case diagnoses. RESULTS The eGFR (Caucasian, Asian, pediatric, and adult formula (CAPA)) was found to be linearly correlated to the eGFR (CKD-EPI) (R2 = 0.5, slope = 0.69, p < 0.0001). In 93/112 (>80%) cases, the eGFR (CAPA) yielded lower values (on average ≈-20%). In 55/112 (49%) cases, the cystatin C-derived CKD stage was lower. CKD reclassification from no-CKD to a kidney-insufficient state (i.e., CKD1/2 to CKD3a/b or 4) or reclassification to a more severe kidney insufficiency (i.e., CKD3a → 3b/4 or 3b → 4) was found in 41/112 (37%) cases. A worse CKD classification (no-CKD → kidney-insufficient) based on the eGFR (CAPA) was plausible in 30% of cases in light of the final case diagnoses. CONCLUSION In elderly patients (>60 years), renal function appears to be systematically overestimated by the creatinine-based eGFR (CKD-EPI), indicating that, for this group, the cystatin C-based eGFR (CAPA) should be used as the first-line diagnostic test.
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Affiliation(s)
- Dario Geißer
- Central Institute of Clinical Chemistry and Laboratory Diagnostics, Medical Faculty, Heinrich Heine University and University Hospital, 40225 Düsseldorf, Germany;
| | - Lina Hetzel
- Division of Cardiology, Pulmonology and Vascular Medicine, Medical Faculty, Heinrich-Heine University, 40225 Düsseldorf, Germany; (L.H.); (R.W.)
| | - Ralf Westenfeld
- Division of Cardiology, Pulmonology and Vascular Medicine, Medical Faculty, Heinrich-Heine University, 40225 Düsseldorf, Germany; (L.H.); (R.W.)
| | - Fritz Boege
- Central Institute of Clinical Chemistry and Laboratory Diagnostics, Medical Faculty, Heinrich Heine University and University Hospital, 40225 Düsseldorf, Germany;
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2
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Semmler A, Mundorf AK, Kuechler AS, Schulze-Bosse K, Heidecke H, Schulze-Forster K, Schott M, Uhrberg M, Weinhold S, Lackner KJ, Pawlitzki M, Meuth SG, Boege F, Ruhrländer J. Chronic Fatigue and Dysautonomia following COVID-19 Vaccination Is Distinguished from Normal Vaccination Response by Altered Blood Markers. Vaccines (Basel) 2023; 11:1642. [PMID: 38005974 PMCID: PMC10674626 DOI: 10.3390/vaccines11111642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 10/20/2023] [Accepted: 10/23/2023] [Indexed: 11/26/2023] Open
Abstract
SARS-CoV-2 mRNA vaccination can entail chronic fatigue/dysautonomia tentatively termed post-acute COVID-19 vaccination syndrome (PACVS). We explored receptor autoantibodies and interleukin-6 (IL-6) as somatic correlates of PACVS. Blood markers determined before and six months after first-time SARS-CoV-2 vaccination of healthy controls (N = 89; 71 females; mean/median age: 39/49 years) were compared with corresponding values of PACVS-affected persons (N = 191; 159 females; mean/median age: 40/39 years) exhibiting chronic fatigue/dysautonomia (≥three symptoms for ≥five months after the last SARS-CoV-2 mRNA vaccination) not due to SARS-CoV-2 infection and/or confounding diseases/medications. Normal vaccination response encompassed decreases in 11 receptor antibodies (by 25-50%, p < 0.0001), increases in two receptor antibodies (by 15-25%, p < 0.0001) and normal IL-6. In PACVS, serological vaccination-response appeared significantly (p < 0.0001) altered, allowing discrimination from normal post-vaccination state (sensitivity = 90%, p < 0.0001) by increased Angiotensin II type 1 receptor antibodies (cut-off ≤ 10.7 U/mL, ROC-AUC = 0.824 ± 0.027), decreased alpha-2B adrenergic receptor antibodies (cut-off ≥ 25.2 U/mL, ROC-AUC = 0.828 ± 0.025) and increased IL-6 (cut-off ≤ 2.3 pg/mL, ROC-AUC = 0.850 ± 0.022). PACVS is thus indicated as a somatic syndrome delineated/detectable by diagnostic blood markers.
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Affiliation(s)
- Amelie Semmler
- Central Institute for Clinical Chemistry and Laboratory Diagnostics, Medical Faculty, University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany; (A.S.); (A.K.M.); (A.S.K.); (K.S.-B.)
| | - Anna Katharina Mundorf
- Central Institute for Clinical Chemistry and Laboratory Diagnostics, Medical Faculty, University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany; (A.S.); (A.K.M.); (A.S.K.); (K.S.-B.)
| | - Anna Sabrina Kuechler
- Central Institute for Clinical Chemistry and Laboratory Diagnostics, Medical Faculty, University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany; (A.S.); (A.K.M.); (A.S.K.); (K.S.-B.)
| | - Karin Schulze-Bosse
- Central Institute for Clinical Chemistry and Laboratory Diagnostics, Medical Faculty, University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany; (A.S.); (A.K.M.); (A.S.K.); (K.S.-B.)
| | - Harald Heidecke
- Cell Trend GmbH, 14943 Luckenwalde, Germany; (H.H.); (K.S.-F.)
| | | | - Matthias Schott
- Division for Specific Endocrinology, Medical Faculty, University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany;
| | - Markus Uhrberg
- Institute for Transplantation Diagnostics and Cell Therapeutics, Medical Faculty, University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany; (M.U.); (S.W.)
| | - Sandra Weinhold
- Institute for Transplantation Diagnostics and Cell Therapeutics, Medical Faculty, University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany; (M.U.); (S.W.)
| | - Karl J. Lackner
- University Medical Center, Johannes Gutenberg-University Mainz, 55101 Mainz, Germany;
| | - Marc Pawlitzki
- Department of Neurology, Heinrich-Heine-University, 40225 Düsseldorf, Germany; (M.P.); (S.G.M.)
| | - Sven Guenther Meuth
- Department of Neurology, Heinrich-Heine-University, 40225 Düsseldorf, Germany; (M.P.); (S.G.M.)
| | - Fritz Boege
- Central Institute for Clinical Chemistry and Laboratory Diagnostics, Medical Faculty, University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany; (A.S.); (A.K.M.); (A.S.K.); (K.S.-B.)
| | - Jana Ruhrländer
- Selbsthilfegruppe Post-Vac-Syndrom Deutschland e.V., 34121 Kassel, Germany;
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3
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Kuechler AS, Heger E, Wirtz M, Weinhold S, Uhrberg M, Boege F, Schulze-Bosse K. Ex Vivo Immune Responsiveness to SARS-CoV-2 Omicron BA.5.1 Following Vaccination with Unmodified mRNA-Vaccine. Vaccines (Basel) 2023; 11:vaccines11030598. [PMID: 36992182 DOI: 10.3390/vaccines11030598] [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] [Received: 01/16/2023] [Revised: 03/02/2023] [Accepted: 03/04/2023] [Indexed: 03/08/2023] Open
Abstract
(1) Background: The high incidence of SARS-CoV-2 infection in vaccinated persons underscores the importance of individualized re-vaccination. PanIg antibodies that act against the S1/-receptor binding domain quantified in serum by a routine diagnostic test (ECLIA, Roche) can be used to gauge the individual ex vivo capacity of SARS-CoV-2 neutralization. However, that test is not adapted to mutations in the S1/-receptor binding domain, having accumulated in SARS-CoV-2 variants. Therefore, it might be unsuited to determine immune-reactivity against SARS-CoV-2 BA.5.1. (2) Method: To address this concern, we re-investigated sera obtained six months after second vaccinations with un-adapted mRNA vaccine Spikevax (Moderna). We related serum levels of panIg against the S1/-receptor binding domain quantified by the un-adapted ECLIA with full virus neutralization capacity against SARS-CoV-2 B.1 or SARS-CoV-2 BA5.1. (3) Results: 92% of the sera exhibited sufficient neutralization capacity against the B.1 strain. Only 20% of the sera sufficiently inhibited the BA5.1 strain. Sera inhibiting BA5.1 could not be distinguished from non-inhibiting sera by serum levels of panIg against the S1/-receptor binding domain quantified by the un-adapted ECLIA. (4) Conclusion: Quantitative serological tests for an antibody against the S1/-receptor binding domain are unsuited as vaccination companion diagnostics, unless they are regularly adapted to mutations that have accumulated in that domain.
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Affiliation(s)
- Anna Sabrina Kuechler
- Central Institute for Clinical Chemistry and Laboratory Diagnostics, Medical Faculty, University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Eva Heger
- Institute for Virology, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50935 Cologne, Germany
| | - Maike Wirtz
- Institute for Virology, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50935 Cologne, Germany
| | - Sandra Weinhold
- Institute for Transplantation Diagnostics and Cell Therapeutics, University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Markus Uhrberg
- Institute for Transplantation Diagnostics and Cell Therapeutics, University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Fritz Boege
- Central Institute for Clinical Chemistry and Laboratory Diagnostics, Medical Faculty, University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Karin Schulze-Bosse
- Central Institute for Clinical Chemistry and Laboratory Diagnostics, Medical Faculty, University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany
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4
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Zweck E, Karschnia M, Scheiber D, Heidecke H, Dechend R, Barthuber C, Kaufmann S, Kelm M, Roden M, Westenfeld R, Szendrödi J, Boege F. Receptor autoantibodies: Associations with cardiac markers, histology, and function in human non-ischaemic heart failure. ESC Heart Fail 2023; 10:1258-1269. [PMID: 36717981 PMCID: PMC10053254 DOI: 10.1002/ehf2.14293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 10/17/2022] [Accepted: 11/08/2022] [Indexed: 02/01/2023] Open
Abstract
AIMS A causal link between non-ischaemic heart failure (HF) and humoral autoimmunity against G-protein-coupled receptors (GPCR) remains unclear except for Chagas' cardiomyopathy. Uncertainty arises from ambiguous reports on incidences of GPCR autoantibodies, spurious correlations of autoantibody levels with disease activity, and lack of standardization and validation of measuring procedures for putatively cardio-pathogenic GPCR autoantibodies. Here, we use validated and certified immune assays presenting native receptors as binding targets. We compared candidate GPCR autoantibody species between HF patients and healthy controls and tested associations of serum autoantibody levels with serological, haemodynamic, metabolic, and functional parameters in HF. METHODS Ninety-five non-ischaemic HF patients undergoing transcatheter endomyocardial biopsy and 60 healthy controls were included. GPCR autoantibodies were determined in serum by IgG binding to native receptors or a cyclic peptide (for β1AR autoantibodies). In patients, cardiac function, volumes, and myocardial structural properties were assessed by cardiac magnetic resonance imaging; right heart catheterization served for determination of cardiac haemodynamics; endomyocardial biopsies were used for histological assessment of cardiomyopathy and determination of cardiac mitochondrial oxidative function by high-resolution respirometry. RESULTS Autoantibodies against β1 adrenergic (β1 AR) , M5-muscarinic (M5AR), and angiotensin II type 2 receptors (AT2R) were increased in HF (all P < 0.001). Autoantibodies against α1 -adrenergic (α1 AR) and angiotensin II type 1 receptors (AT1R) were decreased in HF (all P < 0.001). Correlation of alterations of GPCR autoantibodies with markers of cardiac or systemic inflammation or cardiac damage, haemodynamics, myocardial histology, or left ventricular inflammation (judged by T2 mapping) were weak, even when corrected for total IgG. β1 AR autoantibodies were related inversely to markers of left ventricular fibrosis indicated by T1 mapping (r = -0.362, P < 0.05) and global longitudinal strain (r = -0.323, P < 0.05). AT2R autoantibodies were associated with improved myocardial mitochondrial coupling as measured by high-resolution respirometry in myocardial biopsies (r = -0.352, P < 0.05). In insulin-resistant HF patients, AT2R autoantibodies were decreased (r = -.240, P < 0.05), and AT1R autoantibodies were increased (r = 0.212, P < 0.05). CONCLUSIONS GPCR autoantibodies are markedly altered in HF. However, they are correlated poorly or even inversely to haemodynamic, metabolic, and functional markers of disease severity, myocardial histology, and myocardial mitochondrial efficiency. These observations do not hint towards a specific cardio-pathogenic role of GPCR autoantibodies and suggest that further investigations are required before specific therapies directed at GPCR autoantibodies can be clinically tested in non-ischaemic HF.
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Affiliation(s)
- Elric Zweck
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Düsseldorf, Germany.,German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, München-Neuherberg, Germany.,Department of Cardiology, Pulmonology and Vascular Medicine, Medical Faculty, Heinrich-Heine University, Düsseldorf, Germany
| | - Maximilian Karschnia
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Düsseldorf, Germany.,German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, München-Neuherberg, Germany.,Department of Cardiology, Pulmonology and Vascular Medicine, Medical Faculty, Heinrich-Heine University, Düsseldorf, Germany
| | - Daniel Scheiber
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Düsseldorf, Germany.,German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, München-Neuherberg, Germany.,Department of Cardiology, Pulmonology and Vascular Medicine, Medical Faculty, Heinrich-Heine University, Düsseldorf, Germany
| | | | - Ralf Dechend
- Experimental and Clinical Research Center, University and Max Delbrück Center for Molecular Medicine; Departments of Cardiology and Nephrology, Helios Clinic Berlin-Buch, Berlin, Germany
| | - Carmen Barthuber
- Central Institute for Clinical Chemistry and Laboratory Diagnostics, Medical Faculty, Heinrich Heine University and University Hospital, Düsseldorf, Germany
| | - Sina Kaufmann
- Department of Cardiology, Pulmonology and Vascular Medicine, Medical Faculty, Heinrich-Heine University, Düsseldorf, Germany
| | - Malte Kelm
- Department of Cardiology, Pulmonology and Vascular Medicine, Medical Faculty, Heinrich-Heine University, Düsseldorf, Germany.,Cardiovascular Research Institute Düsseldorf, Medical Faculty, Heinrich-Heine University, Düsseldorf, Germany
| | - Michael Roden
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Düsseldorf, Germany.,German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, München-Neuherberg, Germany.,Cardiovascular Research Institute Düsseldorf, Medical Faculty, Heinrich-Heine University, Düsseldorf, Germany.,Division of Endocrinology and Diabetology, Medical Faculty, Heinrich-Heine University, Düsseldorf, Germany
| | - Ralf Westenfeld
- Department of Cardiology, Pulmonology and Vascular Medicine, Medical Faculty, Heinrich-Heine University, Düsseldorf, Germany
| | - Julia Szendrödi
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Düsseldorf, Germany.,German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, München-Neuherberg, Germany.,Division of Endocrinology and Diabetology, Medical Faculty, Heinrich-Heine University, Düsseldorf, Germany
| | - Fritz Boege
- Central Institute for Clinical Chemistry and Laboratory Diagnostics, Medical Faculty, Heinrich Heine University and University Hospital, Düsseldorf, Germany
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5
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Karschnia M, Zweck E, Scheiber D, Heidecke H, Barthuber C, Kelm M, Roden M, Westenfeld R, Szendroedi J, Boege F. Associations of GPCR autoantibodies with clinical, histological, metabolic and hemodynamic features in non-ischemic heart failure patients. Eur Heart J 2022. [DOI: 10.1093/eurheartj/ehac544.757] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Roughly one third of cases of chronic heart failure (HF) are caused by genetic predisposition, metabolic stress and cardiac inflammation. Animal studies suggest that heart-reactive autoantibodies, most notably those directed against G-protein-coupled receptors (GPCR), could also play a pathogenetic role in the disease. However, so far, a causal link between humoral GPCR-autoimmunity and human non-ischemic heart failure other than Chagas' cardiomyopathy remains unclear.
Purpose
Here, we investigated possible associations of GPCR autoantibodies with inflammatory, hemodynamic, metabolic and functional parameters in patients with chronic non-ischemic HF unrelated to Chagas' disease.
Methods
We prospectively included 95 patients with newly diagnosed non-ischemic heart failure of unknown origin. Basic cardiac characterization comprised transthoracic echocardiography, cardiac magnetic resonance imaging, coronary angiography and right heart catheterization with endomyocardial biopsy. Mitochondrial oxidative phosphorylation capacity and coupling was measured using high-resolution respirometry in permeabilized myocardial fibers. A panel of candidate GPCR-autoantibodies was determined by validated and certified immune-assays in peripheral venous blood of the HF-patients and 60 matched healthy individuals. Results were normalized to total IgG.
Results
Among 10 candidate GPCR-autoantibodies determined, only autoantibodies for α1-adrenergic receptor (α1AR), β1-adrenergic receptor (β1AR), muscarinic receptor M5 (M5AR), angiotensin II receptor type 1 (AT1R) and type 2 (AT2R) exhibited HF-associated alterations:
Autoantibodies against β1AR, M5R and AT2R were increased. Autoantibodies against α1AR and AT1R were decreased (Figure). These alterations were significant (p<0.01), but not, or only weakly, correlated with markers of cardiac inflammation, cardiac damage, hemodynamics, endomyocardial histology or left ventricular inflammation judged by T2-mapping.
However, in HF-patients, increased AT2R autoantibodies were associated with improved myocardial mitochondrial coupling (r=−0.27, p=0.021), and decreased AT2R autoantibodies were associated with insulin resistance (r=−0.24 p=0.027).
Conclusion(s)
Some previously postulated alterations of GPCR autoantibodies were confirmed in thoroughly characterized HF-patients. However, association of these alterations with cardiac function was not traceable, which argues against a specific pathogenic role. Our data are compatible with multifaceted interactions of GPCR-autoantibodies with the myocardium and potentially with glucose metabolism, possibly indicating a disease-modifying or compensatory role.
Funding Acknowledgement
Type of funding sources: Public Institution(s). Main funding source(s): Research comission of the Heinrich-Heine University Duesseldorf
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Affiliation(s)
- M Karschnia
- Heinrich Heine University, Faculty of Medicine , Duesseldorf , Germany
| | - E Zweck
- University Hospital Duesseldorf, Division of Cardiology, Pulmonology and Vascular Medicine , Duesseldorf , Germany
| | - D Scheiber
- University Hospital Duesseldorf, Division of Cardiology, Pulmonology and Vascular Medicine , Duesseldorf , Germany
| | | | - C Barthuber
- University Hospital Duesseldorf, Central Institute for Clinical Chemistry and Laboratory Diagnostics , Duesseldorf , Germany
| | - M Kelm
- University Hospital Duesseldorf, Division of Cardiology, Pulmonology and Vascular Medicine , Duesseldorf , Germany
| | - M Roden
- University Hospital Duesseldorf, Division of Endocrinology and Diabetology , Duesseldorf , Germany
| | - R Westenfeld
- University Hospital Duesseldorf, Division of Cardiology, Pulmonology and Vascular Medicine , Duesseldorf , Germany
| | - J Szendroedi
- University Hospital of Heidelberg, Department of Endocrinology, Diabetology, Metabolism and Clinical Chemistry , Heidelberg , Germany
| | - F Boege
- University Hospital Duesseldorf, Central Institute for Clinical Chemistry and Laboratory Diagnostics , Duesseldorf , Germany
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Kuechler AS, Weinhold S, Boege F, Adams O, Müller L, Babor F, Bennstein SB, Pham TXU, Hejazi M, Reusing SB, Hermsen D, Uhrberg M, Schulze-Bosse K. A Diagnostic Strategy for Gauging Individual Humoral Ex Vivo Immune Responsiveness Following COVID-19 Vaccination. Vaccines (Basel) 2022; 10:vaccines10071044. [PMID: 35891208 PMCID: PMC9322304 DOI: 10.3390/vaccines10071044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 06/24/2022] [Accepted: 06/27/2022] [Indexed: 11/16/2022] Open
Abstract
Purpose: We describe a diagnostic procedure suitable for scheduling (re-)vaccination against severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) according to individual state of humoral immunization. Methods: To clarify the relation between quantitative antibody measurements and humoral ex vivo immune responsiveness, we monitored 124 individuals before, during and six months after vaccination with Spikevax (Moderna, Cambridge, MA, USA). Antibodies against SARS-CoV-2 spike (S1) protein receptor-binding domain (S1-AB) and against nucleocapsid antigens were measured by chemiluminescent immunoassay (Roche). Virus-neutralizing activities were determined by surrogate assays (NeutraLISA, Euroimmune; cPass, GenScript). Neutralization of SARS-CoV-2 in cell culture (full virus NT) served as an ex vivo correlate for humoral immune responsiveness. Results: Vaccination responses varied considerably. Six months after the second vaccination, participants still positive for the full virus NT were safely determined by S1-AB levels ≥1000 U/mL. The full virus NT-positive fraction of participants with S1-AB levels <1000 U/mL was identified by virus-neutralizing activities >70% as determined by surrogate assays (NeutraLISA or cPas). Participants that were full virus NT-negative and presumably insufficiently protected could thus be identified by a sensitivity of >83% and a specificity of >95%. Conclusion: The described diagnostic strategy possibly supports individualized (re-)vaccination schedules based on simple and rapid measurement of serum-based SARS-CoV-2 antibody levels. Our data apply only to WUHAN-type SARS-CoV-2 virus and the current version of the mRNA vaccine from Moderna (Cambridge, MA, USA). Adaptation to other vaccines and more recent SARS-CoV-2 strains will require modification of cut-offs and re-evaluation of sensitivity/specificity.
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Affiliation(s)
- Anna Sabrina Kuechler
- Central Institute for Clinical Chemistry and Laboratory Diagnostics, Medical Faculty, University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany; (F.B.); (D.H.); (K.S.-B.)
- Correspondence: ; Tel.: +49-211-811-7769; Fax: +49-211-811-8021
| | - Sandra Weinhold
- Institute for Transplantation Diagnostics and Cell Therapeutics, University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany; (S.W.); (S.B.B.); (T.-X.U.P.); (M.H.); (S.B.R.); (M.U.)
| | - Fritz Boege
- Central Institute for Clinical Chemistry and Laboratory Diagnostics, Medical Faculty, University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany; (F.B.); (D.H.); (K.S.-B.)
| | - Ortwin Adams
- Institute of Virology, Medical Faculty, University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany; (O.A.); (L.M.)
| | - Lisa Müller
- Institute of Virology, Medical Faculty, University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany; (O.A.); (L.M.)
| | - Florian Babor
- Institute of Hematology, Oncology and Clinical Immunology, Center for Child and Adolescent Health, University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany;
| | - Sabrina B. Bennstein
- Institute for Transplantation Diagnostics and Cell Therapeutics, University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany; (S.W.); (S.B.B.); (T.-X.U.P.); (M.H.); (S.B.R.); (M.U.)
| | - T.-X. Uyen Pham
- Institute for Transplantation Diagnostics and Cell Therapeutics, University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany; (S.W.); (S.B.B.); (T.-X.U.P.); (M.H.); (S.B.R.); (M.U.)
| | - Maryam Hejazi
- Institute for Transplantation Diagnostics and Cell Therapeutics, University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany; (S.W.); (S.B.B.); (T.-X.U.P.); (M.H.); (S.B.R.); (M.U.)
| | - Sarah B. Reusing
- Institute for Transplantation Diagnostics and Cell Therapeutics, University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany; (S.W.); (S.B.B.); (T.-X.U.P.); (M.H.); (S.B.R.); (M.U.)
- Institute of Hematology, Oncology and Clinical Immunology, Center for Child and Adolescent Health, University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany;
| | - Derik Hermsen
- Central Institute for Clinical Chemistry and Laboratory Diagnostics, Medical Faculty, University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany; (F.B.); (D.H.); (K.S.-B.)
| | - Markus Uhrberg
- Institute for Transplantation Diagnostics and Cell Therapeutics, University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany; (S.W.); (S.B.B.); (T.-X.U.P.); (M.H.); (S.B.R.); (M.U.)
| | - Karin Schulze-Bosse
- Central Institute for Clinical Chemistry and Laboratory Diagnostics, Medical Faculty, University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany; (F.B.); (D.H.); (K.S.-B.)
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7
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Backhaus I, Hermsen D, Timm J, Boege F, Lübke N, Göbels K, von der Lieth D, Dragano N. Underascertainment of COVID-19 cases among first responders: a seroepidemiological study. Occup Med (Lond) 2021; 72:225-228. [PMID: 34882771 PMCID: PMC8689783 DOI: 10.1093/occmed/kqab164] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Background Providing frontline support places first responders at a high risk for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Aims This study was aimed to determine the anti-SARS-CoV-2 seroprevalence in a cohort of first responders (i.e. firefighters/paramedics), to detect the underascertainment rate and to assess risk factors associated with seropositivity. Methods We conducted a serological survey among 745 first responders in Germany during 27 November and 4 December 2020 to determine the anti-SARS-CoV-2 seroprevalence using Elecsys® Anti-SARS-CoV-2 immunoassay (Roche Diagnostics, Mannheim, Germany). As part of the examination, participants were asked to provide information on coronavirus disease 2019 (COVID-19)-like-symptoms, information on sociodemographic characteristics and workplace risk factors for a SARS-CoV-2 infection and any prior COVID-19 infection. Descriptive statistics and logistic regression analysis were performed and seroprevalence estimates were adjusted for test sensitivity and specificity. Results The test-adjusted seroprevalence was 4% (95% CI 3.1–6.2) and the underascertainment rate was 2.3. Of those tested SARS-CoV-2 antibody positive, 41% were aware that they had been infected in the past. Seropositivity was elevated among paramedics who worked in the emergency rescue team providing first level of pre-hospital emergency care (6% [95% CI 3.4–8.6]) and those directly exposed to a COVID-19 case (5% [95% CI 3.5–8.1]). Overall, the seroprevalence and the underascertainment rate were higher among first responders than among the general population. Conclusions The high seroprevalence and underascertainment rate highlight the need to mitigate potential transmission within and between first responders and patients. Workplace control measures such as increased and regular COVID-19-testing and the prompt vaccination of all personnel are necessary.
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Affiliation(s)
- I Backhaus
- Institute of Medical Sociology, Centre for Health and Society, Medical Faculty and University Hospital, Heinrich Heine University, Düsseldorf 40225, Germany
| | - D Hermsen
- Central Institute for Clinical Chemistry and Laboratory Diagnostics, Heinrich Heine University, University Hospital, Düsseldorf 40225, Germany
| | - J Timm
- Institute of Virology, Heinrich Heine University, University Hospital, Düsseldorf 40225, Germany
| | - F Boege
- Central Institute for Clinical Chemistry and Laboratory Diagnostics, Heinrich Heine University, University Hospital, Düsseldorf 40225, Germany
| | - N Lübke
- Institute of Virology, Heinrich Heine University, University Hospital, Düsseldorf 40225, Germany
| | - K Göbels
- Public Health Authority Düsseldorf, Düsseldorf 40227, Germany
| | | | - N Dragano
- Institute of Medical Sociology, Centre for Health and Society, Medical Faculty and University Hospital, Heinrich Heine University, Düsseldorf 40225, Germany
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8
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Scherbaum I, Heidecke H, Bunte K, Peters U, Beikler T, Boege F. Autoantibodies against M 5-muscarinic and beta 1-adrenergic receptors in periodontitis patients. Aging (Albany NY) 2020; 12:16609-16620. [PMID: 32857064 PMCID: PMC7485715 DOI: 10.18632/aging.103864] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 07/21/2020] [Indexed: 12/12/2022]
Abstract
Autoantibodies against muscarinic and beta1-adrenergic receptors are considered a potential cause and/or risk factor for chronic heart failure. Association of periodontitis with such autoantibodies and with impaired heart function has been observed in patients exposed to endemic Chagas' disease, which triggers by itself cardiomyopathy and receptor immunization.Here we studied the association between periodontitis, markers of cardiac injury and receptor autoimmunization in periodontitis patients (n = 147) not exposed to Chagas' disease. The autoantibodies were determined by IgG binding to native intact muscarinic and beta1-adrenergic receptors or to a cyclic peptide mimicking the disease-relevant conformational autoepitope presented by the active beta1-adrenergic receptor. Possible cardiac injury and inflammatory status were judged by serum levels of proBNP/Troponin I and CRP/IL-6, respectively. These parameters were analysed in healthy and periodontally diseased individuals as well as before and after periodontal therapy.Patients with periodontitis had significantly (p < 0.001) higher levels of autoantibodies against M5-muscarinic and beta1-adrenergic receptors, which further increased following periodontal therapy. Receptor autoantibodies were associated with increased inflammatory status but not with increased markers of cardiac injury. Thus, our data indicate that periodontitis triggers systemic inflammation, which is associated with receptor autoimmunization, and, independently thereof, with cardiac injury.
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Affiliation(s)
- Isabel Scherbaum
- Central Institute for Clinical Chemistry and Laboratory Diagnostics, Heinrich Heine University Düsseldorf, Medical Faculty, Düsseldorf, Germany
| | | | - Kübra Bunte
- Department of Periodontics, Preventive and Restorative Dentistry, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Ulrike Peters
- Department of Periodontics, Preventive and Restorative Dentistry, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Thomas Beikler
- Department of Periodontics, Preventive and Restorative Dentistry, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Fritz Boege
- Central Institute for Clinical Chemistry and Laboratory Diagnostics, Heinrich Heine University Düsseldorf, Medical Faculty, Düsseldorf, Germany
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9
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Wölfel A, Sättele M, Zechmeister C, Nikolaev VO, Lohse MJ, Boege F, Jahns R, Boivin-Jahns V. Unmasking features of the auto-epitope essential for β 1 -adrenoceptor activation by autoantibodies in chronic heart failure. ESC Heart Fail 2020; 7:1830-1841. [PMID: 32436653 PMCID: PMC7373925 DOI: 10.1002/ehf2.12747] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 03/31/2020] [Accepted: 04/21/2020] [Indexed: 12/15/2022] Open
Abstract
Aims Chronic heart failure (CHF) can be caused by autoantibodies stimulating the heart via binding to first and/or second extracellular loops of cardiac β1‐adrenoceptors. Allosteric receptor activation depends on conformational features of the autoantibody binding site. Elucidating these features will pave the way for the development of specific diagnostics and therapeutics. Our aim was (i) to fine‐map the conformational epitope within the second extracellular loop of the human β1‐adrenoceptor (β1ECII) that is targeted by stimulating β1‐receptor (auto)antibodies and (ii) to generate competitive cyclopeptide inhibitors of allosteric receptor activation, which faithfully conserve the conformational auto‐epitope. Methods and results Non‐conserved amino acids within the β1ECII loop (compared with the amino acids constituting the ECII loop of the β2‐adrenoceptor) were one by one replaced with alanine; potential intra‐loop disulfide bridges were probed by cysteine–serine exchanges. Effects on antibody binding and allosteric receptor activation were assessed (i) by (auto)antibody neutralization using cyclopeptides mimicking β1ECII ± the above replacements, and (ii) by (auto)antibody stimulation of human β1‐adrenoceptors bearing corresponding point mutations. With the use of stimulating β1‐receptor (auto)antibodies raised in mice, rats, or rabbits and isolated from exemplary dilated cardiomyopathy patients, our series of experiments unmasked two features of the β1ECII loop essential for (auto)antibody binding and allosteric receptor activation: (i) the NDPK211–214 motif and (ii) the intra‐loop disulfide bond C209↔C215. Of note, aberrant intra‐loop disulfide bond C209↔C216 almost fully disrupted the functional auto‐epitope in cyclopeptides. Conclusions The conformational auto‐epitope targeted by cardio‐pathogenic β1‐receptor autoantibodies is faithfully conserved in cyclopeptide homologues of the β1ECII loop bearing the NDPK211–214 motif and the C209↔C215 bridge while lacking cysteine C216. Such molecules provide promising tools for novel diagnostic and therapeutic approaches in β1‐autoantibody‐positive CHF.
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Affiliation(s)
- Angela Wölfel
- Institute of Pharmacology and Toxicology, University of Würzburg, Versbacher Str. 9, D-97078, Wuerzburg, Germany.,Rudolf-Virchow-Centre, Josef-Schneider-Str. 2, 97080, Würzburg, Germany.,Rudolf-Virchow-Centre, Pierre Fabre Dermo-Kosmetik GmbH, Jechtinger Straße 13, 79111, Freiburg, Germany
| | - Mathias Sättele
- Institute of Pharmacology and Toxicology, University of Würzburg, Versbacher Str. 9, D-97078, Wuerzburg, Germany
| | - Christina Zechmeister
- Institute of Pharmacology and Toxicology, University of Würzburg, Versbacher Str. 9, D-97078, Wuerzburg, Germany.,Interdisciplinary Bank of Biomaterials and Data (ibdw), University Hospital of Würzburg, Straubmühlweg 2A, D-97078, Würzburg, Germany.,Comprehensive Heart Failure Centre (CFHC), Am Schwarzenberg 11, 978078, Würzburg, Germany
| | - Viacheslav O Nikolaev
- Institute of Pharmacology and Toxicology, University of Würzburg, Versbacher Str. 9, D-97078, Wuerzburg, Germany.,Institute for Molecular Cardiology, Department of Cardiology and Pneumology, University Hospital Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
| | - Martin J Lohse
- Institute of Pharmacology and Toxicology, University of Würzburg, Versbacher Str. 9, D-97078, Wuerzburg, Germany.,Rudolf-Virchow-Centre, Josef-Schneider-Str. 2, 97080, Würzburg, Germany.,Institute Max Delbrück Center for Molecular Research, Berlin-Buch, Robert-Koch-Str. 40, 1000, Berlin, Germany
| | - Fritz Boege
- Rudolf-Virchow-Centre, Institute of Clinical Chemistry and Laboratory Diagnostics, University Hospital, Moorenstraße 5, 40225, Düsseldorf, Germany
| | - Roland Jahns
- Institute of Pharmacology and Toxicology, University of Würzburg, Versbacher Str. 9, D-97078, Wuerzburg, Germany.,Interdisciplinary Bank of Biomaterials and Data (ibdw), University Hospital of Würzburg, Straubmühlweg 2A, D-97078, Würzburg, Germany.,Comprehensive Heart Failure Centre (CFHC), Am Schwarzenberg 11, 978078, Würzburg, Germany
| | - Valérie Boivin-Jahns
- Institute of Pharmacology and Toxicology, University of Würzburg, Versbacher Str. 9, D-97078, Wuerzburg, Germany.,Comprehensive Heart Failure Centre (CFHC), Am Schwarzenberg 11, 978078, Würzburg, Germany
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10
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Sun R, Mak S, Haschemi J, Horn P, Boege F, Luppa PB. Nanodiscs Incorporating Native β1 Adrenergic Receptor as a Novel Approach for the Detection of Pathological Autoantibodies in Patients with Dilated Cardiomyopathy. J Appl Lab Med 2019; 4:391-403. [PMID: 31659076 DOI: 10.1373/jalm.2018.028225] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Accepted: 04/23/2019] [Indexed: 11/06/2022]
Abstract
BACKGROUND Dilated cardiomyopathy (DCM) is a common cause of heart failure with high morbidity and mortality rates. The association of anti-β1 adrenergic receptor (β1AR) autoantibodies with disease progression was shown by various studies and in vivo animal experiments. The prevalence of these disease-driving autoantibodies was estimated as 25% to 75% in DCM. The removal of autoantibodies or the interruption of their action leads to a prolonged improvement of heart function. However, presence and impact of the autoimmune aspect in DCM patients must be examined for targeted treatment. METHODS We developed a heterogeneous immunoassay to support the diagnosis of anti-β1AR autoantibody-induced DCM. The presentation of the native conformational epitope was enabled by reconstitution of human β1AR into lipid bilayer nanodiscs, which stabilize the incorporated receptor in aqueous solution for measurements with standard immunological techniques. RESULTS The incorporation of β1AR into nanodiscs was verified by chromatographic, spectroscopic, and immunological methods. The functionality was shown by interaction assays with appropriate binding partners. Furthermore, β1AR nanodiscs were applied to immunoassays for the detection of anti-β1AR in human sera. Surface plasmon resonance spectroscopy and ELISA were developed, optimized, and validated. The optimized β1AR nanodisc ELISA enabled a simultaneous measurement of 40 samples in duplicate. An interassay variance of 24% and an intraassay variance of 5% were determined. The limit of detection and the limit of quantification were determined as 0.64 ng/mL and 1.26 ng/mL, respectively (related to a monoclonal anti-β1AR). CONCLUSIONS Nanodisc technology is suitable as a novel biomimetic membrane system to stabilize and present β1AR for detection of autoantibodies with immunological methods in DCM patients.
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Affiliation(s)
- Ruoyu Sun
- Institute of Clinical Chemistry and Pathobiochemistry, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Stefanie Mak
- Institute of Clinical Chemistry and Pathobiochemistry, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Jafer Haschemi
- Division of Cardiology, Pulmonology and Vascular Medicine, Medical Faculty, University Düsseldorf, Düsseldorf, Germany
| | - Patrick Horn
- Division of Cardiology, Pulmonology and Vascular Medicine, Medical Faculty, University Düsseldorf, Düsseldorf, Germany
| | - Fritz Boege
- Institute of Clinical Chemistry and Laboratory Diagnostics, Medical Faculty, University Düsseldorf, Düsseldorf, Germany
| | - Peter B Luppa
- Institute of Clinical Chemistry and Pathobiochemistry, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany;
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11
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12
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Horn P, Haschemi J, Scheiber D, Szendroedi J, Zweck E, Sun R, Luppa PB, Saeed D, Boeken U, Kelm M, Roden M, Boege F, Westenfeld R. P2781Sympathomimetic beta-1AR autoantibodies in patients after heart transplantation are associated with higher mitochondrial coupling efficiency. Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy565.p2781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- P Horn
- Department of Cardiology, Pneumology & Angiology, Düsseldorf, Germany
| | - J Haschemi
- Department of Cardiology, Pneumology & Angiology, Düsseldorf, Germany
| | - D Scheiber
- Department of Cardiology, Pneumology & Angiology, Düsseldorf, Germany
| | - J Szendroedi
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Düsseldorf, Germany
| | - E Zweck
- Department of Cardiology, Pneumology & Angiology, Düsseldorf, Germany
| | - R Sun
- Department of Clinical Chemistry, Klinikum rechts der Isar, Technical University Munich, Munich, Germany
| | - P B Luppa
- Department of Clinical Chemistry, Klinikum rechts der Isar, Technical University Munich, Munich, Germany
| | - D Saeed
- Heinrich Heine University, Cardiovascular Surgery, Düsseldorf, Germany
| | - U Boeken
- Heinrich Heine University, Cardiovascular Surgery, Düsseldorf, Germany
| | - M Kelm
- Department of Cardiology, Pneumology & Angiology, Düsseldorf, Germany
| | - M Roden
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Düsseldorf, Germany
| | - F Boege
- Institute of Clinical Chemistry and Laboratory Diagnostics Medical Faculty, Düsseldorf, Germany
| | - R Westenfeld
- Department of Cardiology, Pneumology & Angiology, Düsseldorf, Germany
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13
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Boege F. Relevant effects of beta sub 1 sub -adrenoceptor autoantibodies in chronic heart failure. FRONT BIOSCI-LANDMRK 2018; 23:2146-2156. [DOI: 10.2741/4695] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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14
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Kalfalah F, Janke L, Schiavi A, Tigges J, Ix A, Ventura N, Boege F, Reinke H. Crosstalk of clock gene expression and autophagy in aging. Aging (Albany NY) 2017; 8:1876-1895. [PMID: 27574892 PMCID: PMC5076443 DOI: 10.18632/aging.101018] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Accepted: 08/18/2016] [Indexed: 01/13/2023]
Abstract
Autophagy and the circadian clock counteract tissue degeneration and support longevity in many organisms. Accumulating evidence indicates that aging compromises both the circadian clock and autophagy but the mechanisms involved are unknown. Here we show that the expression levels of transcriptional repressor components of the circadian oscillator, most prominently the human Period homologue PER2, are strongly reduced in primary dermal fibroblasts from aged humans, while raising the expression of PER2 in the same cells partially restores diminished autophagy levels. The link between clock gene expression and autophagy is corroborated by the finding that the circadian clock drives cell-autonomous, rhythmic autophagy levels in immortalized murine fibroblasts, and that siRNA-mediated downregulation of PER2 decreases autophagy levels while leaving core clock oscillations intact. Moreover, the Period homologue lin-42 regulates autophagy and life span in the nematode Caenorhabditis elegans, suggesting an evolutionarily conserved role for Period proteins in autophagy control and aging. Taken together, this study identifies circadian clock proteins as set-point regulators of autophagy and puts forward a model, in which age-related changes of clock gene expression promote declining autophagy levels.
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Affiliation(s)
- Faiza Kalfalah
- University of Düsseldorf, Medical Faculty, Institute of Clinical Chemistry and Laboratory Diagnostics, 40225 Düsseldorf, Germany
| | - Linda Janke
- University of Düsseldorf, Medical Faculty, Institute of Clinical Chemistry and Laboratory Diagnostics, 40225 Düsseldorf, Germany.,IUF-Leibniz Research Institute for Environmental Medicine, 40225 Düsseldorf, Germany
| | - Alfonso Schiavi
- University of Düsseldorf, Medical Faculty, Institute of Clinical Chemistry and Laboratory Diagnostics, 40225 Düsseldorf, Germany.,IUF-Leibniz Research Institute for Environmental Medicine, 40225 Düsseldorf, Germany
| | - Julia Tigges
- IUF-Leibniz Research Institute for Environmental Medicine, 40225 Düsseldorf, Germany
| | - Alexander Ix
- University of Düsseldorf, Medical Faculty, Institute of Clinical Chemistry and Laboratory Diagnostics, 40225 Düsseldorf, Germany
| | - Natascia Ventura
- University of Düsseldorf, Medical Faculty, Institute of Clinical Chemistry and Laboratory Diagnostics, 40225 Düsseldorf, Germany.,IUF-Leibniz Research Institute for Environmental Medicine, 40225 Düsseldorf, Germany
| | - Fritz Boege
- University of Düsseldorf, Medical Faculty, Institute of Clinical Chemistry and Laboratory Diagnostics, 40225 Düsseldorf, Germany
| | - Hans Reinke
- University of Düsseldorf, Medical Faculty, Institute of Clinical Chemistry and Laboratory Diagnostics, 40225 Düsseldorf, Germany.,IUF-Leibniz Research Institute for Environmental Medicine, 40225 Düsseldorf, Germany
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15
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Boege F. Comment on Shahadevan et al. "The relationship of single strand breaks in DNA to breast cancer risk and to tissue concentrations of oestrogens". Biomarkers 2017; 22:698-699. [PMID: 28286966 DOI: 10.1080/1354750x.2017.1306755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Fritz Boege
- a Institute of Clinical Chemistry and Laboratory Diagnostics , University Hospital , Düsseldorf , Germany
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16
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Bornholz B, Benninghaus T, Reinke Y, Felix SB, Roggenbuck D, Jahns-Boivin V, Jahns R, Boege F. A standardised FACS assay based on native, receptor transfected cells for the clinical diagnosis and monitoring of β1-adrenergic receptor autoantibodies in human heart disease. Clin Chem Lab Med 2016; 54:683-91. [PMID: 26408610 DOI: 10.1515/cclm-2015-0603] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 08/31/2015] [Indexed: 12/14/2022]
Abstract
BACKGROUND Autoantibodies against β1-adrenergic receptors (β1AR) that stimulate cardiac cAMP-production play a causal role in the pathogenesis of human heart failure. Patients can be subjected to specific therapies, if the presence of potentially cardio-noxious β1AR-autoantibodies is reliably diagnosed. This requires assessment of IgG-interactions with the native β1AR because β1AR-autoantibodies target a conformational epitope inadequately presented by denatured receptors or linear peptides. Here, we report on a standardised diagnostic procedure for the assessment of β1AR-autoantibodies in heart failure patients, which is based on IgG-binding to native human β1AR. METHODS Good laboratory practice (GLP)-conform measurement of β1AR-autoantibodies was based on flow-cytometric quantification of differential IgG-binding to native HT1080 cells overexpressing biofluorescent human β1AR or not. Receptor-specific IgG-binding was derived from IgG-related median fluorescence of β1AR-positive cells corrected for background staining of β1AR-negative cells admixed to each measurement. The slope of IgG binding at two different concentrations was used as measure for the titre/avidity of β1AR-autoantibodies. RESULTS Sensitivity and specificity of the novel procedure for high β1AR-autoantibody levels in dilated cardiomyopathy patients (n=40, NYHA class III-IV) relative to n=40 matched healthy subjects was >90%. It was similar to functional assays considered the gold standard and vastly superior to existing screening-procedures employing fixed cells or linear receptor-peptides as auto-antigenic targets. Inter-assay scatter was 7%-15% and linear dilution recovery was within ±10% of expected values throughout. CONCLUSIONS The novel assay possibly provides a tool to determine true prevalence and clinical impact of β1AR-autoantibodies. Furthermore, it may serve as companion diagnostic for therapies specifically directed at β1AR-autoantibodies.
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17
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Raschke S, Spickermann S, Toncian T, Swantusch M, Boeker J, Giesen U, Iliakis G, Willi O, Boege F. Ultra-short laser-accelerated proton pulses have similar DNA-damaging effectiveness but produce less immediate nitroxidative stress than conventional proton beams. Sci Rep 2016; 6:32441. [PMID: 27578260 PMCID: PMC5006042 DOI: 10.1038/srep32441] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [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: 05/12/2016] [Accepted: 08/04/2016] [Indexed: 11/09/2022] Open
Abstract
Ultra-short proton pulses originating from laser-plasma accelerators can provide instantaneous dose rates at least 10(7)-fold in excess of conventional, continuous proton beams. The impact of such extremely high proton dose rates on A549 human lung cancer cells was compared with conventionally accelerated protons and 90 keV X-rays. Between 0.2 and 2 Gy, the yield of DNA double strand breaks (foci of phosphorylated histone H2AX) was not significantly different between the two proton sources or proton irradiation and X-rays. Protein nitroxidation after 1 h judged by 3-nitrotyrosine generation was 2.5 and 5-fold higher in response to conventionally accelerated protons compared to laser-driven protons and X-rays, respectively. This difference was significant (p < 0.01) between 0.25 and 1 Gy. In conclusion, ultra-short proton pulses originating from laser-plasma accelerators have a similar DNA damaging potential as conventional proton beams, while inducing less immediate nitroxidative stress, which probably entails a distinct therapeutic potential.
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Affiliation(s)
- S. Raschke
- Institute for Laser and Plasma Physics, University of Düsseldorf, Düsseldorf, Germany
- Institute of Clinical Chemistry and Laboratory Diagnostics, University of Düsseldorf, Medical Faculty, Germany
- Institute of Medical Radiation Biology, University of Duisburg-Essen, Medical School, Essen, Germany
| | - S. Spickermann
- Institute for Laser and Plasma Physics, University of Düsseldorf, Düsseldorf, Germany
| | - T. Toncian
- Institute for Laser and Plasma Physics, University of Düsseldorf, Düsseldorf, Germany
| | - M. Swantusch
- Institute for Laser and Plasma Physics, University of Düsseldorf, Düsseldorf, Germany
| | - J. Boeker
- Institute for Laser and Plasma Physics, University of Düsseldorf, Düsseldorf, Germany
| | - U. Giesen
- Physikalisch-Technische Bundesanstalt (PTB), Braunschweig, Germany
| | - G. Iliakis
- Institute of Medical Radiation Biology, University of Duisburg-Essen, Medical School, Essen, Germany
| | - O. Willi
- Institute for Laser and Plasma Physics, University of Düsseldorf, Düsseldorf, Germany
| | - F. Boege
- Institute of Clinical Chemistry and Laboratory Diagnostics, University of Düsseldorf, Medical Faculty, Germany
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18
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Bornholz B, Hanzen B, Reinke Y, Felix SB, Boege F. Impact of common β1-adrenergic receptor polymorphisms on the interaction with agonistic autoantibodies in dilated cardiomyopathy. Int J Cardiol 2016; 214:83-5. [DOI: 10.1016/j.ijcard.2016.03.032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 03/12/2016] [Indexed: 10/22/2022]
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19
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Marko D, Boege F. A possible link between nutritional uptake of ubiquitous topoisomerase inhibitors and autism? Int J Dev Neurosci 2016; 53:8-9. [DOI: 10.1016/j.ijdevneu.2016.06.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 06/09/2016] [Indexed: 10/21/2022] Open
Affiliation(s)
- Doris Marko
- University of ViennaFaculty of ChemistryDepartment of Food Chemistry and ToxicologyAustria
| | - Fritz Boege
- Central Institute of Clinical Chemistry and Laboratory DiagnosticsUniversity of DüsseldorfGermany
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20
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Kalfalah FM, Berg E, Christensen MO, Linka RM, Dirks WG, Boege F, Mielke C. Spatio-temporal regulation of the human licensing factor Cdc6 in replication and mitosis. Cell Cycle 2016; 14:1704-15. [PMID: 25875233 PMCID: PMC4614858 DOI: 10.1080/15384101.2014.1000182] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
To maintain genome stability, the thousands of replication origins of mammalian genomes must only initiate replication once per cell cycle. This is achieved by a strict temporal separation of ongoing replication in S phase, and the formation of pre-replicative complexes in the preceding G1 phase, which "licenses" each origin competent for replication. The contribution of the loading factor Cdc6 to the timing of the licensing process remained however elusive due to seemingly contradictory findings concerning stabilization, degradation and nuclear export of Cdc6. Using fluorescently tagged Cdc6 (Cdc6-YFP) expressed in living cycling cells, we demonstrate here that Cdc6-YFP is stable and chromatin-associated during mitosis and G1 phase. It undergoes rapid proteasomal degradation during S phase initiation followed by active export to the cytosol during S and G2 phases. Biochemical fractionation abolishes this nuclear exclusion, causing aberrant chromatin association of Cdc6-YFP and, likely, endogenous Cdc6, too. In addition, we demonstrate association of Cdc6 with centrosomes in late G2 and during mitosis. These results show that multiple Cdc6-regulatory mechanisms coexist but are tightly controlled in a cell cycle-specific manner.
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Affiliation(s)
- Faiza M Kalfalah
- a Institute of Clinical Chemistry and Laboratory Diagnostics; University Düsseldorf; Medical Faculty , Düsseldorf , Germany
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Bornholz B, Hanzen B, Reinke Y, Felix SB, Jahns R, Schimke I, Wallukat G, Boege F. Detection of DCM-associated β1-adrenergic receptor autoantibodies requires functional readouts or native human β1-receptors as targets. Int J Cardiol 2016; 202:728-30. [DOI: 10.1016/j.ijcard.2015.10.068] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 10/04/2015] [Indexed: 11/24/2022]
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22
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Fuellen G, Schofield P, Flatt T, Schulz RJ, Boege F, Kraft K, Rimbach G, Ibrahim S, Tietz A, Schmidt C, Köhling R, Simm A. Living Long and Well: Prospects for a Personalized Approach to the Medicine of Ageing. Gerontology 2015; 62:409-16. [PMID: 26675034 DOI: 10.1159/000442746] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 11/25/2015] [Indexed: 11/19/2022] Open
Abstract
Research into ageing and its underlying molecular basis enables us to develop and implement targeted interventions to ameliorate or cure its consequences. However, the efficacy of interventions often differs widely between individuals, suggesting that populations should be stratified or even individualized. Large-scale cohort studies in humans, similar systematic studies in model organisms as well as detailed investigations into the biology of ageing can provide individual validated biomarkers and mechanisms, leading to recommendations for targeted interventions. Human cohort studies are already ongoing, and they can be supplemented by in silico simulations. Systematic studies in animal models are made possible by the use of inbred strains or genetic reference populations of mice. Combining the two, a comprehensive picture of the various determinants of ageing and 'health span' can be studied in detail, and an appreciation of the relevance of results from model organisms to humans is emerging. The interactions between genotype and environment, particularly the psychosocial environment, are poorly studied in both humans and model organisms, presenting serious challenges to any approach to a personalized medicine of ageing. To increase the success of preventive interventions, we argue that there is a pressing need for an individualized evaluation of interventions such as physical exercise, nutrition, nutraceuticals and calorie restriction mimetics as well as psychosocial and environmental factors, separately and in combination. The expected extension of the health span enables us to refocus health care spending on individual prevention, starting in late adulthood, and on the brief period of morbidity at very old age.
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Affiliation(s)
- Georg Fuellen
- Institute for Biostatistics and Informatics in Medicine und Ageing Research (IBIMA), Rostock University Medical Center, Rostock, Germany
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Waldera-Lupa DM, Kalfalah F, Florea AM, Sass S, Kruse F, Rieder V, Tigges J, Fritsche E, Krutmann J, Busch H, Boerries M, Meyer HE, Boege F, Theis F, Reifenberger G, Stühler K. Proteome-wide analysis reveals an age-associated cellular phenotype of in situ aged human fibroblasts. Aging (Albany NY) 2015; 6:856-78. [PMID: 25411231 PMCID: PMC4247387 DOI: 10.18632/aging.100698] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
We analyzed an ex vivo model of in situ aged human dermal fibroblasts, obtained from 15 adult healthy donors from three different age groups using an unbiased quantitative proteome-wide approach applying label-free mass spectrometry. Thereby, we identified 2409 proteins, including 43 proteins with an age-associated abundance change. Most of the differentially abundant proteins have not been described in the context of fibroblasts’ aging before, but the deduced biological processes confirmed known hallmarks of aging and led to a consistent picture of eight biological categories involved in fibroblast aging, namely proteostasis, cell cycle and proliferation, development and differentiation, cell death, cell organization and cytoskeleton, response to stress, cell communication and signal transduction, as well as RNA metabolism and translation. The exhaustive analysis of protein and mRNA data revealed that 77% of the age-associated proteins were not linked to expression changes of the corresponding transcripts. This is in line with an associated miRNA study and led us to the conclusion that most of the age-associated alterations detected at the proteome level are likely caused post-transcriptionally rather than by differential gene expression. In summary, our findings led to the characterization of novel proteins potentially associated with fibroblast aging and revealed that primary cultures of in situ aged fibroblasts are characterized by moderate age-related proteomic changes comprising the multifactorial process of aging.
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Affiliation(s)
- Daniel M Waldera-Lupa
- Institute for Molecular Medicine, Heinrich-Heine-University, Düsseldorf, Germany. Molecular Proteomics Laboratory, Biomedical Research Centre (BMFZ), Heinrich-Heine-University, Düsseldorf, Germany
| | - Faiza Kalfalah
- Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich-Heine-University, Med. Faculty, Düsseldorf, Germany
| | - Ana-Maria Florea
- Department of Neuropathology, Heinrich-Heine-University, Düsseldorf, and German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Steffen Sass
- Institute of Computational Biology, Helmholtz Center Munich, German Research Center for Environmental Health, Neuherberg, Germany
| | - Fabian Kruse
- Institute for Molecular Medicine, Heinrich-Heine-University, Düsseldorf, Germany. Molecular Proteomics Laboratory, Biomedical Research Centre (BMFZ), Heinrich-Heine-University, Düsseldorf, Germany
| | - Vera Rieder
- Institute for Molecular Medicine, Heinrich-Heine-University, Düsseldorf, Germany. Molecular Proteomics Laboratory, Biomedical Research Centre (BMFZ), Heinrich-Heine-University, Düsseldorf, Germany
| | - Julia Tigges
- Leibniz Research Institute for Environmental Medicine (IUF), Düsseldorf, Germany
| | - Ellen Fritsche
- Leibniz Research Institute for Environmental Medicine (IUF), Düsseldorf, Germany
| | - Jean Krutmann
- Leibniz Research Institute for Environmental Medicine (IUF), Düsseldorf, Germany
| | - Hauke Busch
- Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University Freiburg, Freiburg, Germany. German Cancer Consortium (DKTK), Freiburg, Germany. German Cancer Research Center (DKFZ), D-69120, Heidelberg, Germany
| | - Melanie Boerries
- Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University Freiburg, Freiburg, Germany. German Cancer Consortium (DKTK), Freiburg, Germany. German Cancer Research Center (DKFZ), D-69120, Heidelberg, Germany
| | - Helmut E Meyer
- Department of Biomedical Research, Leibniz-Institute for Analytical Science - ISAS, Dortmund, Germany
| | - Fritz Boege
- Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich-Heine-University, Med. Faculty, Düsseldorf, Germany
| | - Fabian Theis
- Department of Mathematics, Technical University Munich, Garching, Germany
| | - Guido Reifenberger
- Department of Neuropathology, Heinrich-Heine-University, Düsseldorf, and German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Kai Stühler
- Institute for Molecular Medicine, Heinrich-Heine-University, Düsseldorf, Germany. Molecular Proteomics Laboratory, Biomedical Research Centre (BMFZ), Heinrich-Heine-University, Düsseldorf, Germany
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24
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Jahns R, Boege F. Questionable Validity of Peptide-Based ELISA Strategies in the Diagnostics of Cardiopathogenic Autoantibodies That Activate G-Protein-Coupled Receptors. Cardiology 2015; 131:149-50. [DOI: 10.1159/000376546] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Accepted: 01/22/2015] [Indexed: 11/19/2022]
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25
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Kalfalah F, Seggewiß S, Walter R, Tigges J, Moreno-Villanueva M, Bürkle A, Ohse S, Busch H, Boerries M, Hildebrandt B, Royer-Pokora B, Boege F. Structural chromosome abnormalities, increased DNA strand breaks and DNA strand break repair deficiency in dermal fibroblasts from old female human donors. Aging (Albany NY) 2015; 7:110-122. [PMID: 25678531 PMCID: PMC4359693 DOI: 10.18632/aging.100723] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Accepted: 01/01/2015] [Indexed: 06/04/2023]
Abstract
Dermal fibroblasts provide a paradigmatic model of cellular adaptation to long-term exogenous stress and ageing processes driven thereby. Here we addressed whether fibroblast ageing analysedex vivo entails genome instability. Dermal fibroblasts from human female donors aged 20-67 years were studied in primary culture at low population doubling. Under these conditions, the incidence of replicative senescence and rates of age-correlated telomere shortening were insignificant. Genome-wide gene expression analysis revealed age-related impairment of mitosis, telomere and chromosome maintenance and induction of genes associated with DNA repair and non-homologous end-joining, most notably XRCC4 and ligase 4. We observed an age-correlated drop in proliferative capacity and age-correlated increases in heterochromatin marks, structural chromosome abnormalities (deletions, translocations and chromatid breaks), DNA strand breaks and histone H2AX-phosphorylation. In a third of the cells from old and middle-aged donors repair of X-ray induced DNA strand breaks was impaired despite up-regulation of DNA repair genes. The distinct phenotype of genome instability, increased heterochromatinisation and (in 30% of the cases futile) up-regulation of DNA repair genes was stably maintained over several cell passages indicating that it represents a feature of geroconversion that is distinct from cellular senescence, as it does not encompass a block of proliferation.
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Affiliation(s)
- Faiza Kalfalah
- Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich-Heine-University, Med. Faculty, Düsseldorf, Germany
| | - Sabine Seggewiß
- Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich-Heine-University, Med. Faculty, Düsseldorf, Germany
- Institute of Human Genetics and Anthropology, Heinrich-Heine-University, Med. Faculty, Düsseldorf, Germany
| | - Regina Walter
- Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich-Heine-University, Med. Faculty, Düsseldorf, Germany
| | - Julia Tigges
- Leibniz Research Institute for Environmental Medicine (IUF), Düsseldorf, Germany
| | | | - Alexander Bürkle
- Molecular Toxicology Group, Dept. of Biology, University of Konstanz, Konstanz, Germany
| | - Sebastian Ohse
- Systems Biology of the Cellular Microenvironment Group, Institute of Molecular Medicine and Cell Research, University of Freiburg, Freiburg, Germany
| | - Hauke Busch
- Systems Biology of the Cellular Microenvironment Group, Institute of Molecular Medicine and Cell Research, University of Freiburg, Freiburg, Germany
- German Cancer Research Centre (DKFZ), Heidelberg, Germany
- German Cancer Consortium (DKTK), Freiburg, Germany
| | - Melanie Boerries
- Systems Biology of the Cellular Microenvironment Group, Institute of Molecular Medicine and Cell Research, University of Freiburg, Freiburg, Germany
- German Cancer Research Centre (DKFZ), Heidelberg, Germany
- German Cancer Consortium (DKTK), Freiburg, Germany
| | - Barbara Hildebrandt
- Institute of Human Genetics and Anthropology, Heinrich-Heine-University, Med. Faculty, Düsseldorf, Germany
| | - Brigitte Royer-Pokora
- Institute of Human Genetics and Anthropology, Heinrich-Heine-University, Med. Faculty, Düsseldorf, Germany
| | - Fritz Boege
- Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich-Heine-University, Med. Faculty, Düsseldorf, Germany
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26
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Röck K, Tigges J, Sass S, Schütze A, Florea AM, Fender AC, Theis FJ, Krutmann J, Boege F, Fritsche E, Reifenberger G, Fischer JW. miR-23a-3p Causes Cellular Senescence by Targeting Hyaluronan Synthase 2: Possible Implication for Skin Aging. J Invest Dermatol 2015; 135:369-377. [DOI: 10.1038/jid.2014.422] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Revised: 08/27/2014] [Accepted: 08/29/2014] [Indexed: 12/13/2022]
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27
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Bornholz B, Roggenbuck D, Jahns R, Boege F. Diagnostic and therapeutic aspects of β1-adrenergic receptor autoantibodies in human heart disease. Autoimmun Rev 2014; 13:954-62. [DOI: 10.1016/j.autrev.2014.08.021] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Accepted: 06/16/2014] [Indexed: 01/19/2023]
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28
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Kalfalah F, Sobek S, Bornholz B, Götz-Rösch C, Tigges J, Fritsche E, Krutmann J, Köhrer K, Deenen R, Ohse S, Boerries M, Busch H, Boege F. Inadequate mito-biogenesis in primary dermal fibroblasts from old humans is associated with impairment of PGC1A-independent stimulation. Exp Gerontol 2014; 56:59-68. [PMID: 24699405 DOI: 10.1016/j.exger.2014.03.017] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Revised: 03/15/2014] [Accepted: 03/22/2014] [Indexed: 01/17/2023]
Abstract
Extrinsic skin ageing converges on the dermis, a post-mitotic tissue compartment consisting of extracellular matrix and long-lived fibroblasts prone to damage accumulation and maladaptation. Aged human fibroblasts exhibit mitochondrial and nuclear dysfunctions, which may be a cause or consequence of ageing. We report on a systematic study of human dermal fibroblasts retrieved from female donors aged 20-67 years and analysed ex vivo at low population doubling precluding replicative senescence. According to gene set enrichment analysis of genome wide array data, the most prominent age-associated change of the transcriptome was decreased expression of mitochondrial genes. Consistent with that, mitochondrial content and cell proliferation declined with donor age. This was associated with upregulation of AMP-dependent protein kinase (AMPK), increased mRNA levels of PPARγ-coactivator 1α (PGC1A) and decreased levels of NAD(+)-dependent deacetylase sirtuin 1. In the old cells the PGC1A-mediated mito-biogenetic response to direct AMPK-stimulation by AICAR was undiminished, while the PGC1A-independent mito-biogenetic response to starvation was attenuated and accompanied by increased ROS-production. In summary, these observations suggest an age-associated decline in PGC1A-independent mito-biogenesis, which is insufficiently compensated by upregulation of the AMPK/PGC1A-axis leading under baseline conditions to decreased mitochondrial content and reductive overload of residual respiratory capacity.
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Affiliation(s)
- Faiza Kalfalah
- Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich Heine University, Med. Faculty, Düsseldorf, Germany
| | - Stefan Sobek
- Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich Heine University, Med. Faculty, Düsseldorf, Germany
| | - Beatrice Bornholz
- Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich Heine University, Med. Faculty, Düsseldorf, Germany
| | - Christine Götz-Rösch
- Leibniz Research Institute for Environmental Medicine (IUF), Düsseldorf, Germany
| | - Julia Tigges
- Leibniz Research Institute for Environmental Medicine (IUF), Düsseldorf, Germany
| | - Ellen Fritsche
- Leibniz Research Institute for Environmental Medicine (IUF), Düsseldorf, Germany
| | - Jean Krutmann
- Leibniz Research Institute for Environmental Medicine (IUF), Düsseldorf, Germany
| | - Karl Köhrer
- Genomics & Transcriptomics Laboratory, Biomedical Research Centre (BMFZ), Heinrich Heine University, Düsseldorf, Germany
| | - René Deenen
- Genomics & Transcriptomics Laboratory, Biomedical Research Centre (BMFZ), Heinrich Heine University, Düsseldorf, Germany
| | - Sebastian Ohse
- Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University, Freiburg, Germany; Freiburg Institute for Advanced Studies - FRIAS, Albert-Ludwigs-University, Freiburg, Germany
| | - Melanie Boerries
- Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University, Freiburg, Germany; German Cancer Consortium (DKTK), Freiburg, Germany; German Cancer Research Center (DKFZ), Heidelberg, Germany; Freiburg Institute for Advanced Studies - FRIAS, Albert-Ludwigs-University, Freiburg, Germany
| | - Hauke Busch
- Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University, Freiburg, Germany; German Cancer Consortium (DKTK), Freiburg, Germany; German Cancer Research Center (DKFZ), Heidelberg, Germany; Freiburg Institute for Advanced Studies - FRIAS, Albert-Ludwigs-University, Freiburg, Germany
| | - Fritz Boege
- Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich Heine University, Med. Faculty, Düsseldorf, Germany.
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29
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Tigges J, Krutmann J, Fritsche E, Haendeler J, Schaal H, Fischer JW, Kalfalah F, Reinke H, Reifenberger G, Stühler K, Ventura N, Gundermann S, Boukamp P, Boege F. The hallmarks of fibroblast ageing. Mech Ageing Dev 2014; 138:26-44. [PMID: 24686308 DOI: 10.1016/j.mad.2014.03.004] [Citation(s) in RCA: 150] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2013] [Revised: 03/11/2014] [Accepted: 03/18/2014] [Indexed: 12/26/2022]
Abstract
Ageing is influenced by the intrinsic disposition delineating what is maximally possible and extrinsic factors determining how that frame is individually exploited. Intrinsic and extrinsic ageing processes act on the dermis, a post-mitotic skin compartment mainly consisting of extracellular matrix and fibroblasts. Dermal fibroblasts are long-lived cells constantly undergoing damage accumulation and (mal-)adaptation, thus constituting a powerful indicator system for human ageing. Here, we use the systematic of ubiquitous hallmarks of ageing (Lopez-Otin et al., 2013, Cell 153) to categorise the available knowledge regarding dermal fibroblast ageing. We discriminate processes inducible in culture from phenomena apparent in skin biopsies or primary cells from old donors, coming to the following conclusions: (i) Fibroblasts aged in culture exhibit most of the established, ubiquitous hallmarks of ageing. (ii) Not all of these hallmarks have been detected or investigated in fibroblasts aged in situ (in the skin). (iii) Dermal fibroblasts aged in vitro and in vivo exhibit additional features currently not considered ubiquitous hallmarks of ageing. (iv) The ageing process of dermal fibroblasts in their physiological tissue environment has only been partially elucidated, although these cells have been a preferred model of cell ageing in vitro for decades.
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Affiliation(s)
- Julia Tigges
- Leibniz Research Institute for Environmental Medicine (IUF), Düsseldorf, Germany
| | - Jean Krutmann
- Leibniz Research Institute for Environmental Medicine (IUF), Düsseldorf, Germany
| | - Ellen Fritsche
- Leibniz Research Institute for Environmental Medicine (IUF), Düsseldorf, Germany
| | - Judith Haendeler
- Leibniz Research Institute for Environmental Medicine (IUF), Düsseldorf, Germany; Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich-Heine-University, Med. Faculty, Düsseldorf, Germany
| | - Heiner Schaal
- Center for Microbiology and Virology, Institute of Virology, Heinrich-Heine-University, Med. Faculty, D-40225 Düsseldorf, Germany
| | - Jens W Fischer
- Institute for Pharmacology and Clinical Pharmacology, Heinrich-Heine-University, Med. Faculty, Düsseldorf, Germany
| | - Faiza Kalfalah
- Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich-Heine-University, Med. Faculty, Düsseldorf, Germany
| | - Hans Reinke
- Leibniz Research Institute for Environmental Medicine (IUF), Düsseldorf, Germany; Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich-Heine-University, Med. Faculty, Düsseldorf, Germany
| | - Guido Reifenberger
- Department of Neuropathology, Heinrich-Heine-University, Med. Faculty, Düsseldorf, Germany
| | - Kai Stühler
- Institute for Molecular Medicine, Heinrich-Heine-University, Med. Faculty, Düsseldorf, Germany; Molecular Proteomics Laboratory, Centre for Biological and Medical Research (BMFZ), Heinrich-Heine-University, Düsseldorf, Germany
| | - Natascia Ventura
- Leibniz Research Institute for Environmental Medicine (IUF), Düsseldorf, Germany; Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich-Heine-University, Med. Faculty, Düsseldorf, Germany
| | | | - Petra Boukamp
- German Cancer Research Centre (DKFZ), Heidelberg, Germany
| | - Fritz Boege
- Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich-Heine-University, Med. Faculty, Düsseldorf, Germany.
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Abstract
DNA topoisomerases pass DNA strands through each other, a function essential for all DNA metabolic processes that create supercoils or entanglements of DNA. Topoisomerases play an ambivalent role in nuclear genome maintenance: Deficiency compromises gene transcription, replication and chromosome segregation, while the inherent DNA-cleavage activity of the enzymes endangers DNA integrity. Indeed, many DNA-damaging agents act through enhancing topoisomerase DNA cleavage. Mitochondrial DNA (mtDNA) clearly requires topoisomerase activity for transcription and replication, because it is a closed, double-stranded DNA molecule. Three topoisomerases have so far been found in mammalian mitochondria (I, IIβ, IIIα), but their precise role in mtDNA metabolism, mitochondrial maintenance and respiratory function remains mostly unclear. It is a reasonable surmise that these enzymes exhibit similar ambiguity with respect to genome maintenance and gene transcription as their nuclear counterparts. Here, we review what is known about the physiological roles of mitochondrial topoisomerases and draft three scenarios of how these enzymes possibly contribute to ageing-related mtDNA attrition and respiratory chain dysfunction. These scenarios are: mtDNA attrition by exogenously stimulated topoisomerase DNA cleavage, unbalancing of mitochondrial and nuclear transcription by direct effects on mitochondrial transcription, and contributions to enhanced mtDNA entanglement and recombination.
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Affiliation(s)
- Stefan Sobek
- Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich Heine University, Med. Faculty, Düsseldorf, Germany
| | - Fritz Boege
- Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich Heine University, Med. Faculty, Düsseldorf, Germany.
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Sobek S, Dalla Rosa I, Pommier Y, Bornholz B, Kalfalah F, Zhang H, Wiesner RJ, von Kleist-Retzow JC, Hillebrand F, Schaal H, Mielke C, Christensen MO, Boege F. Negative regulation of mitochondrial transcription by mitochondrial topoisomerase I. Nucleic Acids Res 2013; 41:9848-57. [PMID: 23982517 PMCID: PMC3834834 DOI: 10.1093/nar/gkt768] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Mitochondrial topoisomerase I is a genetically distinct mitochondria-dedicated enzyme with a crucial but so far unknown role in the homeostasis of mitochondrial DNA metabolism. Here, we present data suggesting a negative regulatory function in mitochondrial transcription or transcript stability. Deficiency or depletion of mitochondrial topoisomerase I increased mitochondrial transcripts, whereas overexpression lowered mitochondrial transcripts, depleted respiratory complexes I, III and IV, decreased cell respiration and raised superoxide levels. Acute depletion of mitochondrial topoisomerase I triggered neither a nuclear mito-biogenic stress response nor compensatory topoisomerase IIβ upregulation, suggesting the concomitant increase in mitochondrial transcripts was due to release of a local inhibitory effect. Mitochondrial topoisomerase I was co-immunoprecipitated with mitochondrial RNA polymerase. It selectively accumulated and rapidly exchanged at a subset of nucleoids distinguished by the presence of newly synthesized RNA and/or mitochondrial RNA polymerase. The inactive Y559F-mutant behaved similarly without affecting mitochondrial transcripts. In conclusion, mitochondrial topoisomerase I dampens mitochondrial transcription and thereby alters respiratory capacity. The mechanism involves selective association of the active enzyme with transcriptionally active nucleoids and a direct interaction with mitochondrial RNA polymerase. The inhibitory role of topoisomerase I in mitochondrial transcription is strikingly different from the stimulatory role of topoisomerase I in nuclear transcription.
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Affiliation(s)
- Stefan Sobek
- Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich-Heine-University, Med. Faculty, D-40225 Düsseldorf, Germany, Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA, Center for Physiology and Pathophysiology, Institute of Vegetative Physiology, University of Köln, D-50931 Köln, Germany, Center for Molecular Medicine Cologne, University of Köln, D-50931 Köln, Germany, Cologne Excellence Cluster on Cellular Stress Responses in Aging-associated Diseases, University of Köln, D-50931 Köln, Germany, Department of Pediatrics, Med. Faculty, University of Köln, D-50931 Köln, Germany and Center for Microbiology and Virology, Institute of Virology, Heinrich-Heine-University, Med. Faculty, D-40225 Düsseldorf, Germany
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Haarmann-Stemmann T, Boege F, Krutmann J. Adaptive and maladaptive responses in skin: mild heat exposure protects against UVB-induced photoaging in mice. J Invest Dermatol 2013; 133:868-71. [PMID: 23486428 DOI: 10.1038/jid.2012.435] [Citation(s) in RCA: 9] [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: 11/09/2022]
Abstract
In this issue, Matsuda et al. demonstrate the protective effect of mild heat preconditioning on UVB-induced photoaging in SKH-1 hairless mice. Mild heat exposure stimulates the upregulation of HSP70 chaperones, which inhibit the activities of matrix-degenerating enzymes, thereby avoiding wrinkle formation. This newly identified heat-mediated process of adaptation to UVB radiation exposure opens new opportunities to slow extrinsic skin aging.
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Bornholz B, Weidtkamp-Peters S, Schmitmeier S, Seidel CAM, Herda LR, Felix SB, Lemoine H, Hescheler J, Nguemo F, Schäfer C, Christensen MO, Mielke C, Boege F. Impact of human autoantibodies on β1-adrenergic receptor conformation, activity, and internalization. Cardiovasc Res 2012. [PMID: 23208588 PMCID: PMC3567785 DOI: 10.1093/cvr/cvs350] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Aims Autoantibodies against second extracellular loops of β1-adrenergic receptors frequent in dilated cardiomyopathy confer myocardial dysfunction presumably via cAMP stimulation. Here, we investigate the autoantibody impact on receptor conformation and function. Methods and results IgG was prepared from patients with dilated cardiomyopathy, matched healthy donors (10 each) or commercial IgG preparations (2). IgG binding to β1-adrenergic receptor peptides was detected in 5 of 10 patients and 2 of 10 controls. IgG colocalization with the native receptor was detected in 8 of 10 patients and 1 of 10 controls (10 of 10 patients and 7 of 10 controls at >30 mg IgG/L). All IgGs exhibiting receptor colocalization triggered changes in receptor conformation (determined with fluorescent sensors) not stringently correlated to cAMP stimulation, suggesting the induction of more or less active receptor conformations. Receptor-activating IgG was detected in 8 of 10 patients but only 1 of 10 controls. In addition, IgG from 8 of 10 patients and 3 of 10 controls attenuated receptor internalization (measured by total internal reflection fluorescence microscopy). IgG-inducing inactive receptor conformations had no effect on subsequent cAMP stimulation by isoproterenol. IgG-inducing active receptor conformations dampened or augmented subsequent cAMP stimulation by isoproterenol, depending on whether receptor internalization was attenuated or not. Corresponding IgG effects on the basal beating rate and chronotropic isoproterenol response of embryonic human cardiomyocytes were observed. Conclusions (i) Autoantibodies trigger conformation changes in the β1-adrenergic receptor molecule. (ii) Some also attenuate receptor internalization. (iii) Combinations thereof increase the basal beating rate of cardiomyocytes and optionally entail dampening of their chronotropic catecholamine responses. (iv) The latter effects seem specific for patient autoantibodies, which also have higher levels.
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Affiliation(s)
- Beatrice Bornholz
- Institute of Clinical Chemistry and Laboratory Diagnostics, University Hospital, Moorenstrasse 5, Düsseldorf 40225, Germany
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Herda LR, Felix SB, Boege F. Drug-like actions of autoantibodies against receptors of the autonomous nervous system and their impact on human heart function. Br J Pharmacol 2012; 166:847-57. [PMID: 22220626 PMCID: PMC3412294 DOI: 10.1111/j.1476-5381.2012.01828.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Antibodies against cholinergic and adrenergic receptors (adrenoceptors) are frequent in serum of patients with chronic heart failure. Their prevalence is associated with Chagas' disease, idiopathic dilated cardiomyopathy (DCM), and ischaemic heart disease. Among the epitopes targeted are first and second extracellular loops of the β-adrenergic (β-adrenoceptor) and M2 muscarinic receptor. β1-adrenoceptor autoantibodies affect radioligand binding and cardiomyocyte function similar to agonists. Corresponding rodent immunizations induce symptoms compatible with chronic heart failure that are reversible upon removal of the antibodies, transferable via the serum and abrogated by adrenergic antagonists. In DCM patients, prevalence and stimulatory efficacy of β1-adrenoceptor autoantibodies are correlated to the decline in cardiac function, ventricular arrhythmia and higher incidence of cardiac death. In conclusion, such autoantibodies seem to cause or promote chronic human left ventricular dysfunction by acting on their receptor targets in a drug-like fashion. However, the pharmacology of this interaction is poorly understood. It is unclear how the autoantibodies trigger changes in receptor activity and second messenger coupling and how that is related to the pathogenesis and severity of the associated diseases. Here, we summarize the available evidence regarding these issues and discuss these findings in the light of recent knowledge about the conformational activation of the human β2-adrenoceptor and the properties of bona fide cardiopathogenic autoantibodies derived from immune-adsorption therapy of DCM patients. These considerations might contribute to the conception of therapy regimen aimed at counteracting or neutralizing cardiopathogenic receptor autoantibodies.
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Affiliation(s)
- L R Herda
- Department of Internal Medicine B, University of Greifswald, Greifswald, Germany
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Berg E, Christensen MO, Dalla Rosa I, Wannagat E, Jänicke RU, Rösner LM, Dirks WG, Boege F, Mielke C. XRCC4 controls nuclear import and distribution of Ligase IV and exchanges faster at damaged DNA in complex with Ligase IV. DNA Repair (Amst) 2011; 10:1232-42. [DOI: 10.1016/j.dnarep.2011.09.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2010] [Revised: 09/07/2011] [Accepted: 09/13/2011] [Indexed: 12/13/2022]
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Kalfalah FM, Mielke C, Christensen MO, Baechler S, Marko D, Boege F. Genotoxicity of dietary, environmental and therapeutic topoisomerase II poisons is uniformly correlated to prolongation of enzyme DNA residence. Mol Nutr Food Res 2011; 55 Suppl 1:S127-42. [DOI: 10.1002/mnfr.201000509] [Citation(s) in RCA: 25] [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: 10/12/2010] [Revised: 01/15/2011] [Accepted: 01/21/2011] [Indexed: 12/28/2022]
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37
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Fehr M, Baechler S, Kropat C, Mielke C, Boege F, Pahlke G, Marko D. Repair of DNA damage induced by the mycotoxin alternariol involves tyrosyl-DNA phosphodiesterase 1. Mycotoxin Res 2010; 26:247-56. [DOI: 10.1007/s12550-010-0063-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2010] [Revised: 06/29/2010] [Accepted: 07/02/2010] [Indexed: 11/29/2022]
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Kawamura R, Pope LH, Christensen MO, Sun M, Terekhova K, Boege F, Mielke C, Andersen AH, Marko JF. Mitotic chromosomes are constrained by topoisomerase II-sensitive DNA entanglements. ACTA ACUST UNITED AC 2010; 188:653-63. [PMID: 20194637 PMCID: PMC2835934 DOI: 10.1083/jcb.200910085] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Chromatin entanglements undergo specific protein-mediated compaction to fold into mitotic chromosomes. We have analyzed the topological organization of chromatin inside mitotic chromosomes. We show that mitotic chromatin is heavily self-entangled through experiments in which topoisomerase (topo) II is observed to reduce mitotic chromosome elastic stiffness. Single chromosomes were relaxed by 35% by exogenously added topo II in a manner that depends on hydrolysable adenosine triphosphate (ATP), whereas an inactive topo II cleavage mutant did not change chromosome stiffness. Moreover, experiments using type I topos produced much smaller relaxation effects than topo II, indicating that chromosome relaxation by topo II is caused by decatenation and/or unknotting of double-stranded DNA. In further experiments in which chromosomes are first exposed to protease to partially release protein constraints on chromatin, ATP alone relaxes mitotic chromosomes. The topo II–specific inhibitor ICRF-187 blocks this effect, indicating that it is caused by endogenous topo II bound to the chromosome. Our experiments show that DNA entanglements act in concert with protein-mediated compaction to fold chromatin into mitotic chromosomes.
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Affiliation(s)
- Ryo Kawamura
- Department of Physics, University of Illinois at Chicago, Chicago, IL 60607, USA
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Dalla Rosa I, Goffart S, Wurm M, Wiek C, Essmann F, Sobek S, Schroeder P, Zhang H, Krutmann J, Hanenberg H, Schulze-Osthoff K, Mielke C, Pommier Y, Boege F, Christensen MO. Adaptation of topoisomerase I paralogs to nuclear and mitochondrial DNA. Nucleic Acids Res 2009; 37:6414-28. [PMID: 19720733 PMCID: PMC2770673 DOI: 10.1093/nar/gkp708] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Topoisomerase I is essential for DNA metabolism in nuclei and mitochondria. In yeast, a single topoisomerase I gene provides for both organelles. In vertebrates, topoisomerase I is divided into nuclear and mitochondrial paralogs (Top1 and Top1mt). To assess the meaning of this gene duplication, we targeted Top1 to mitochondria or Top1mt to nuclei. Overexpression in the fitting organelle served as control. Targeting of Top1 to mitochondria blocked transcription and depleted mitochondrial DNA. This was also seen with catalytically inactive Top1 mutants, but not with Top1mt overexpressed in mitochondria. Targeting of Top1mt to the nucleus revealed that it was much less able to interact with mitotic chromosomes than Top1 overexpressed in the nucleus. Similar experiments with Top1/Top1mt hybrids assigned these functional differences to structural divergences in the DNA-binding core domains. We propose that adaptation of this domain to different chromatin environments in nuclei and mitochondria has driven evolutional development and conservation of organelle-restricted topoisomerase I paralogs in vertebrates.
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Affiliation(s)
- Ilaria Dalla Rosa
- Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich-Heine-University, Medical School, D-40225 Düsseldorf, Germany
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Gieseler F, Boege F, Biersack H, Spohn B, Clark M, Wilms K. Nuclear Topoisomerase II Activity Changes During HL-60 Leukemic Cell Differentiation: Alterations in Drug Sensitivity and pH Dependency. Leuk Lymphoma 2009; 5:273-9. [DOI: 10.3109/10428199109068137] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Fehr M, Pahlke G, Fritz J, Christensen MO, Boege F, Altemöller M, Podlech J, Marko D. Alternariol acts as a topoisomerase poison, preferentially affecting the IIα isoform. Mol Nutr Food Res 2009; 53:441-51. [PMID: 18727009 DOI: 10.1002/mnfr.200700379] [Citation(s) in RCA: 142] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Markus Fehr
- Institute of Applied Biosciences, Section of Food Toxicology, Universität Karlsruhe (TH), Karlsruhe, Germany
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Bornholz B, Schmitmeier S, Christensen MO, Mielke C, Boege F. The β
1
‐adrenergic receptor is activated by autoantibodies from patients with dilated cardiomyopathy. FASEB J 2008. [DOI: 10.1096/fasebj.22.2_supplement.288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Beatrice Bornholz
- Institute of Clinical Chemistry and Laboratory DiagnosticsHeinrich‐Heine‐University Medical SchoolDuesseldorfGermany
| | - Stephanie Schmitmeier
- Institute of Clinical Chemistry and Laboratory DiagnosticsHeinrich‐Heine‐University Medical SchoolDuesseldorfGermany
- Dept. Biochemistry of MicronutrientsGerman Institute for Human NutritionNuthetalGermany
| | - Morten Overby Christensen
- Institute of Clinical Chemistry and Laboratory DiagnosticsHeinrich‐Heine‐University Medical SchoolDuesseldorfGermany
| | - Christian Mielke
- Institute of Clinical Chemistry and Laboratory DiagnosticsHeinrich‐Heine‐University Medical SchoolDuesseldorfGermany
| | - Fritz Boege
- Institute of Clinical Chemistry and Laboratory DiagnosticsHeinrich‐Heine‐University Medical SchoolDuesseldorfGermany
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Mielke C, Kalfalah FM, Christensen MO, Boege F. Rapid and prolonged stalling of human DNA topoisomerase I in UVA-irradiated genomic areas. DNA Repair (Amst) 2007; 6:1757-63. [PMID: 17765665 DOI: 10.1016/j.dnarep.2007.06.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [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: 04/27/2007] [Revised: 06/22/2007] [Accepted: 06/25/2007] [Indexed: 12/31/2022]
Abstract
DNA topoisomerase I appears to be involved in DNA damage and repair in a complex manner. The enzyme is required for DNA maintenance and repair, but it may also damage DNA through its covalently DNA-bound, catalytic intermediate. The latter mechanism plays a role in tumor cell killing by camptothecins, but seems also involved in oxidative cell killing and certain stages of apoptosis. Stalling and/or suicidal DNA cleavage of topoisomerase I adjacent to nicks and modified DNA bases has been demonstrated in vitro. Here, we investigate the enzyme's interactions with UVA-induced DNA lesions inside living cells. We irradiated cells expressing GFP-tagged topoisomerase I with an UVA laser focused through a confocal microscope at confined areas of the nuclei. At irradiated sites, topoisomerase I accumulated within seconds, and accumulation lasted for more than 90 min. This effect was apparently due to reduced mobility, although the enzyme was not immobilized at the irradiated nuclear sites. Similar observations were made with mutant versions of topoisomerase I lacking the active site tyrosine or the N-terminal domain, but not with the N-terminal domain alone. Thus, accumulation of topoisomerase I at UVA-modified DNA sites is most likely due to non-covalent binding to damaged DNA, and not suicidal cleavage of such lesions. The rapid onset of accumulation suggests that topoisomerase I functions in this context as a component of DNA damage recognition and/or a cofactor of fast DNA-repair processes. However, the prolonged duration of accumulation suggests that it is also involved in more long-termed processes.
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Affiliation(s)
- Christian Mielke
- Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich-Heine-University, Medical School, Moorenstrasse 5, D-40225 Düsseldorf, Germany.
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Linka RM, Porter AC, Volkov A, Mielke C, Boege F, Christensen MO. C-terminal regions of topoisomerase IIalpha and IIbeta determine isoform-specific functioning of the enzymes in vivo. Nucleic Acids Res 2007; 35:3810-22. [PMID: 17526531 PMCID: PMC1920234 DOI: 10.1093/nar/gkm102] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.9] [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] [Indexed: 11/14/2022] Open
Abstract
Topoisomerase II removes supercoils and catenanes generated during DNA metabolic processes such as transcription and replication. Vertebrate cells express two genetically distinct isoforms (alpha and beta) with similar structures and biochemical activities but different biological roles. Topoisomerase IIalpha is essential for cell proliferation, whereas topoisomerase IIbeta is required only for aspects of nerve growth and brain development. To identify the structural features responsible for these differences, we exchanged the divergent C-terminal regions (CTRs) of the two human isoforms (alpha 1173-1531 and beta 1186-1621) and tested the resulting hybrids for complementation of a conditional topoisomerase IIalpha knockout in human cells. Proliferation was fully supported by all enzymes bearing the alpha CTR. The alpha CTR also promoted chromosome binding of both enzyme cores, and was by itself chromosome-bound, suggesting a role in enzyme targeting during mitosis. In contrast, enzymes bearing the beta CTR supported proliferation only rarely and when expressed at unusually high levels. A similar analysis of the divergent N-terminal regions (alpha 1-27 and beta 1-43) revealed no role in isoform-specific functions. Our results show that it is the CTRs of human topoisomerase II that determine their isoform-specific functions in proliferating cells. They also indicate persistence of some functional redundancy between the two isoforms.
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Affiliation(s)
- René M. Linka
- Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich-Heine-University, Medical School, Moorenstrasse 5, D-40225 Düsseldorf, Germany and Gene Targeting Group, Department of Haematology, Imperial College Faculty of Medicine, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK
| | - Andrew C.G. Porter
- Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich-Heine-University, Medical School, Moorenstrasse 5, D-40225 Düsseldorf, Germany and Gene Targeting Group, Department of Haematology, Imperial College Faculty of Medicine, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK
| | - Arsen Volkov
- Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich-Heine-University, Medical School, Moorenstrasse 5, D-40225 Düsseldorf, Germany and Gene Targeting Group, Department of Haematology, Imperial College Faculty of Medicine, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK
| | - Christian Mielke
- Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich-Heine-University, Medical School, Moorenstrasse 5, D-40225 Düsseldorf, Germany and Gene Targeting Group, Department of Haematology, Imperial College Faculty of Medicine, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK
| | - Fritz Boege
- Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich-Heine-University, Medical School, Moorenstrasse 5, D-40225 Düsseldorf, Germany and Gene Targeting Group, Department of Haematology, Imperial College Faculty of Medicine, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK
| | - Morten O. Christensen
- Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich-Heine-University, Medical School, Moorenstrasse 5, D-40225 Düsseldorf, Germany and Gene Targeting Group, Department of Haematology, Imperial College Faculty of Medicine, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK
- *To whom correspondence should be addressed. +49 211 8118036; +49 211 8118021;
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Habermeyer M, Fritz J, Barthelmes HU, Christensen MO, Larsen MK, Boege F, Marko D. Anthocyanidins modulate the activity of human DNA topoisomerases I and II and affect cellular DNA integrity. Chem Res Toxicol 2005; 18:1395-404. [PMID: 16167831 DOI: 10.1021/tx050039n] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In the present study, we investigated the effect of anthocyanidins on human topoisomerases I and II and its relevance for DNA integrity within human cells. Anthocyanidins bearing vicinal hydroxy groups at the B-ring (delphinidin, DEL; cyanidin, CY) were found to potently inhibit the catalytic activity of human topoisomerases I and II, without discriminating between the IIalpha and the IIbeta isoforms. However, in contrast to topoisomerase poisons, DEL and CY did not stabilize the covalent DNA-topoisomerase intermediates (cleavable complex) of topoisomerase I or II. Using recombinant topoisomerase I, the presence of CY or DEL (> or = 1 microM) effectively prohibited the stabilization of the cleavable complex by the topoisomerase I poison camptothecin. We furthermore investigated whether the potential protective effect vs topoisomerase I poisons is reflected also on the cellular level, affecting the DNA damaging properties of camptothecin. Indeed, in HT29 cells, low micromolar concentrations of DEL (1-10 microM) significantly diminished the DNA strand breaking effect of camptothecin (100 microM). However, at concentrations > or = 50 microM, all anthocyanidins tested (delphinidin, cyanidin, malvidin, pelargonidin, and paeonidin), including those not interfering with topoisomerases, were found to induce DNA strand breaks in the comet assay. All of these analogues were able to compete with ethidium bromide for the intercalation into calf thymus DNA and to replace the minor groove binder Hoechst 33258. These data indicate substantial affinity to double-stranded DNA, which might contribute at least to the DNA strand breaking effect of anthocyanidins at higher concentrations (> or = 50 microM).
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Affiliation(s)
- Michael Habermeyer
- Department of Chemistry, Division of Food Chemistry and Environmental Toxicology, University of Kaiserslautern, Erwin-Schroedinger Strasse 52, 67663 Kaiserslautern, Germany
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Barthelmes HU, Habermeyer M, Christensen MO, Mielke C, Interthal H, Pouliot JJ, Boege F, Marko D. TDP1 overexpression in human cells counteracts DNA damage mediated by topoisomerases I and II. J Biol Chem 2004; 279:55618-25. [PMID: 15494395 DOI: 10.1074/jbc.m405042200] [Citation(s) in RCA: 115] [Impact Index Per Article: 5.8] [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: 12/31/2022] Open
Abstract
Tyrosyl DNA phosphodiesterase 1 (TDP1) is a repair enzyme that removes adducts, e.g. of topoisomerase I from the 3'-phosphate of DNA breaks. When expressed in human cells as biofluorescent chimera, TDP1 appeared more mobile than topoisomerase I, less accumulated in nucleoli, and not chromosome-bound at early mitosis. Upon exposure to camptothecin both proteins were cleared from nucleoli and rendered less mobile in the nucleoplasm. However, with TDP1 this happened much more slowly reflecting most likely the redistribution of nucleolar structures upon inhibition of rDNA transcription. Thus, a steady association of TDP1 with topoisomerase I seems unlikely, whereas its integration into repair complexes assembled subsequently to the stabilization of DNA.topoisomerase I intermediates is supported. Cells expressing GFP-tagged TDP1 > 100-fold in excess of endogenous TDP1 exhibited a significant reduction of DNA damage induced by the topoisomerase I poison camptothecin and could be selected by that drug. Surprisingly, DNA damage induced by the topoisomerase II poison VP-16 was also diminished to a similar extent, whereas DNA damage independent of topoisomerase I or II was not affected. Overexpression of the inactive mutant GFP-TDP1(H263A) at similar levels did not reduce DNA damage by camptothecin or VP-16. These observations confirm a requirement of active TDP1 for the repair of topoisomerase I-mediated DNA damage. Our data also suggest a role of TDP1 in the repair of DNA damage mediated by topoisomerase II, which is less clear. Since overexpression of TDP1 did not compromise cell proliferation, it could be a pleiotropic resistance mechanism in cancer therapy.
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Affiliation(s)
- Hans U Barthelmes
- Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich-Heine-University, Medical School, Moorenstrasse 5, D-40225 Düsseldorf, Germany
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Athale CA, Christensen MO, Eils R, Boege F, Mielke C. Inferring a System Model of Subcellular Topoisomerase IIβ Localization Dynamics. OMICS: A Journal of Integrative Biology 2004; 8:167-75. [PMID: 15268774 DOI: 10.1089/1536231041388339] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Measuring the mobility of proteins in living cells has become critical to many studies in cell biology and forms the basis for discussion on sub-cellular dynamics. Increasingly localization networks are being put together into compartment models to represent the exchange of molecules, represented mathematically as ordinary differential equations (ODE). The set-up is based on published literature, the "knowledge" of the investigator and 3D visualization of the data. Here we demonstrate this method on the example of a simple distribution model of the molecule Topoisomerase II beta (Topo II beta), nuclear protein that modifies DNA topology. It is found in high concentration in the nucleolus and diffuse in the nucleoplasm, demonstrating a non-membranous inhomogeneity in its distribution. We expand on the simple model by adding additional components to fit fluorescence recovery after photobleaching (FRAP) experiments for protein (GFP) labeled Topo II beta to measure its mobility. This model is then validated by comparing it with alternative scenarios and shown to have predictive power.
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Affiliation(s)
- Chaitanya A Athale
- Intelligent Bioinformatics Systems, German Cancer Research Centre (DKFZ), Heidelberg, Germany.
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Abstract
Solar UV light induces a variety of DNA lesions in the genome. Enhanced cleavage of such base modifications by topoisomerase II has been demonstrated in vitro, but it is unclear what will arise from an interplay of these mechanisms in the genome of a living cell exposed to UV light. To address this question, we have subjected cells expressing biofluorescent topoisomerase IIalpha or IIbeta to DNA base modifications inflicted by a UVA laser at 364 nm through a confocal microscope in a locally confined manner. At DNA sites thus irradiated, we observed rapid, long term (>90 min) accumulation of topoisomerase IIalpha and IIbeta, which was accompanied by a decrease in mobility but not immobilization of the enzyme. The catalytic topoisomerase II inhibitor ICRF-187 prevented the effect when added to the cell culture before the UVA pulse but promoted it when added thereafter. Self-primed in situ extension with rhodamine-dUTP revealed massive DNA breakage at the UVA-exposed spot. Culturing the cells with ICRF-187 before UVA-exposure prevented such breaks. In conclusion, we show in a living cell nucleus that UVA-modified DNA is preferentially targeted and processed by topoisomerase IIalpha and IIbeta. This results in increased levels of topoisomerase II-mediated DNA breaks, but formation of immobile, stable topoisomerase II.DNA intermediates is not notably promoted. Inhibition of topoisomerase II activity by ICRF-187 greatly diminishes UVA-induced DNA breakage, implying topoisomerase IIalpha and IIbeta as endogenous co-factors modulating and possibly aggravating the impact of UVA light on the genome.
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Affiliation(s)
- Christian Mielke
- Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich-Heine-University, Medical School, Moorenstrasse 5, D-40225 Düsseldorf, Germany.
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Christensen MO, Krokowski RM, Barthelmes HU, Hock R, Boege F, Mielke C. Distinct effects of topoisomerase I and RNA polymerase I inhibitors suggest a dual mechanism of nucleolar/nucleoplasmic partitioning of topoisomerase I. J Biol Chem 2004; 279:21873-82. [PMID: 15014084 DOI: 10.1074/jbc.m400498200] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [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: 11/06/2022] Open
Abstract
Topoisomerase I is mostly nucleolar, because it plays a preeminent role in ribosomal DNA (rDNA) transcription. It is cleared from nucleoli following exposure to drugs stabilizing covalent DNA intermediates of the enzyme (e.g. camptothecin) or inhibiting RNA polymerases (e.g. actinomycin D), an effect summarily attributed to blockade of rDNA transcription. Here we show that two distinct mechanisms are at work: (i). Both drugs induce inactivation and segregation of the rRNA transcription machinery. With actinomycin D this leads to a co-migration of RNA-polymerase I and topoisomerase I to the nucleolar perimeter. The process has a slow onset (>20 min), is independent of topoisomerase I activity, but requires the N-terminal domain of the enzyme to colocalize with RNA polymerase I. (ii). Camptothecin induces, in addition, immobilization of active topoisomerase I on genomic DNA resulting in rapid nucleolar clearance and spreading of the enzyme to the entire nucleoplasm. This effect is independent of the state of rRNA transcription, involves segregation of topoisomerase I from RNA polymerase I, has a rapid onset (<1 min), and requires catalytic activity but neither the N-terminal domain of topoisomerase I nor its major sumoylation site. Thus, nucleolar/nucleoplasmic partitioning of topoisomerase I is regulated by interactions with RNA polymerase I and DNA but not by sumoylation.
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Affiliation(s)
- Morten O Christensen
- Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich Heine University, Medical School, Moorenstrasse 5, D-40225 Duesseldorf
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Christensen MO, Barthelmes HU, Boege F, Mielke C. Residues 190-210 of human topoisomerase I are required for enzyme activity in vivo but not in vitro. Nucleic Acids Res 2004; 31:7255-63. [PMID: 14654701 PMCID: PMC291868 DOI: 10.1093/nar/gkg927] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [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: 11/14/2022] Open
Abstract
DNA-topoisomerase I (topo I) unwinds the DNA- double helix by cutting one strand and allowing rotation of the other. In vitro, this function does not require the N-terminal domain of the enzyme, which is believed to regulate cellular properties. To assess this role, we studied the cellular distribution and mobility of green fluorescent protein-chimera of human topo I lacking either the entire N-terminal domain or a portion of it. We find that topo I truncated up to position 210 is not stabilized by camptothecin in covalent DNA-complexes inside a living cell, whereas in vitro it retains full DNA-relaxation activity, and is targeted by camptothecin in the usual manner. This difference is not shared with a fragment lacking the N-terminal domain up to position 190, indicating that residues 190-210 play a crucial role for the activity of the enzyme in its physiological environment, but not in vitro. Since it is impossible to discriminate in vivo whether this region is required for topo I to form covalent DNA intermediates in the cell, or just for camptothecin to bind and stabilize such complexes, we could not explain precisely these cellular observations. However, inactivity in vivo of the enzyme lacking this region is indicated by a lesser cytotoxicity.
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Affiliation(s)
- Morten O Christensen
- Institute of Clinical Chemistry and Laboratory Diagnostics, Heinrich-Heine-University, Medical School, Moorenstrasse 5, D-40225 Duesseldorf, Germany
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