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Renard E, Walton RD, Benoist D, Brette F, Bru-Mercier G, Chaigne S, Charron S, Constantin M, Douard M, Dubes V, Guillot B, Hof T, Magat J, Martinez ME, Michel C, Pallares-Lupon N, Pasdois P, Récalde A, Vaillant F, Sacher F, Labrousse L, Rogier J, Kyndt F, Baudic M, Schott JJ, Barc J, Probst V, Sarlandie M, Marionneau C, Ashton JL, Hocini M, Haïssaguerre M, Bernus O. Functional Epicardial Conduction Disturbances Due to a SCN5A Variant Associated With Brugada Syndrome. JACC Clin Electrophysiol 2023; 9:1248-1261. [PMID: 37227351 PMCID: PMC10406612 DOI: 10.1016/j.jacep.2023.03.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 03/06/2023] [Accepted: 03/10/2023] [Indexed: 05/26/2023]
Abstract
BACKGROUND Brugada syndrome is a significant cause of sudden cardiac death (SCD), but the underlying mechanisms remain hypothetical. OBJECTIVES This study aimed to elucidate this knowledge gap through detailed ex vivo human heart studies. METHODS A heart was obtained from a 15-year-old adolescent boy with normal electrocardiogram who experienced SCD. Postmortem genotyping was performed, and clinical examinations were done on first-degree relatives. The right ventricle was optically mapped, followed by high-field magnetic resonance imaging and histology. Connexin-43 and NaV1.5 were localized by immunofluorescence, and RNA and protein expression levels were studied. HEK-293 cell surface biotinylation assays were performed to examine NaV1.5 trafficking. RESULTS A Brugada-related SCD diagnosis was established for the donor because of a SCN5A Brugada-related variant (p.D356N) inherited from his mother, together with a concomitant NKX2.5 variant of unknown significance. Optical mapping demonstrated a localized epicardial region of impaired conduction near the outflow tract, in the absence of repolarization alterations and microstructural defects, leading to conduction blocks and figure-of-8 patterns. NaV1.5 and connexin-43 localizations were normal in this region, consistent with the finding that the p.D356N variant does not affect the trafficking, nor the expression of NaV1.5. Trends of decreased NaV1.5, connexin-43, and desmoglein-2 protein levels were noted; however, the RT-qPCR results suggested that the NKX2-5 variant was unlikely to be involved. CONCLUSIONS This study demonstrates for the first time that SCD associated with a Brugada-SCN5A variant can be caused by localized functionally, not structurally, impaired conduction.
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Affiliation(s)
- Estelle Renard
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France; Université Bordeaux, Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France.
| | - Richard D Walton
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France; Université Bordeaux, Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France
| | - David Benoist
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France; Université Bordeaux, Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France
| | - Fabien Brette
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France; Université Bordeaux, Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France
| | - Gilles Bru-Mercier
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France; Université Bordeaux, Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France
| | - Sébastien Chaigne
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France; Université Bordeaux, Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France
| | - Sabine Charron
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France; Université Bordeaux, Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France
| | - Marion Constantin
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France; Université Bordeaux, Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France
| | - Matthieu Douard
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France; Université Bordeaux, Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France
| | - Virginie Dubes
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France; Université Bordeaux, Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France
| | - Bastien Guillot
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France; Université Bordeaux, Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France
| | - Thomas Hof
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France; Université Bordeaux, Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France
| | - Julie Magat
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France; Université Bordeaux, Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France
| | - Marine E Martinez
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France; Université Bordeaux, Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France
| | - Cindy Michel
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France; Université Bordeaux, Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France
| | - Néstor Pallares-Lupon
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France; Université Bordeaux, Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France
| | - Philippe Pasdois
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France; Université Bordeaux, Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France
| | - Alice Récalde
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France; Université Bordeaux, Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France
| | - Fanny Vaillant
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France; Université Bordeaux, Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France
| | - Frédéric Sacher
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France; Université Bordeaux, Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France; Centre Hospitalier Universitaire de Bordeaux, Département d'électrophysiologie et de stimulation cardiaques, Hôpital Cardiologique du Haut-Lévêque, Pessac, France
| | - Louis Labrousse
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France; Centre Hospitalier Universitaire de Bordeaux, Département de chirurgie cardiovasculaire, Hôpital Cardiologique du Haut-Lévêque, Pessac, France
| | - Julien Rogier
- Centre Hospitalier Universitaire de Bordeaux, Coordination des prélèvements d'organes et de tissus, Bordeaux, France
| | - Florence Kyndt
- Nantes Université, Centre Hospitalier Universitaire Nantes, CNRS, INSERM, l'institut du thorax, Nantes, France; Centre Hospitalier Universitaire Nantes, Service de génétique médicale, Nantes, France
| | - Manon Baudic
- L'Institut du thorax, INSERM, CNRS, Université Nantes, Nantes, France
| | - Jean-Jacques Schott
- Nantes Université, Centre Hospitalier Universitaire Nantes, CNRS, INSERM, l'institut du thorax, Nantes, France
| | - Julien Barc
- Nantes Université, CNRS, INSERM, l'institut du thorax, Nantes, France
| | - Vincent Probst
- Nantes Université, Centre Hospitalier Universitaire Nantes, CNRS, INSERM, l'institut du thorax, Nantes, France
| | - Marine Sarlandie
- L'Institut du thorax, INSERM, CNRS, Université Nantes, Nantes, France
| | - Céline Marionneau
- L'Institut du thorax, INSERM, CNRS, Université Nantes, Nantes, France
| | - Jesse L Ashton
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Mélèze Hocini
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France; Université Bordeaux, Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France; Centre Hospitalier Universitaire de Bordeaux, Département d'électrophysiologie et de stimulation cardiaques, Hôpital Cardiologique du Haut-Lévêque, Pessac, France
| | - Michel Haïssaguerre
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France; Université Bordeaux, Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France; Centre Hospitalier Universitaire de Bordeaux, Département d'électrophysiologie et de stimulation cardiaques, Hôpital Cardiologique du Haut-Lévêque, Pessac, France
| | - Olivier Bernus
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France; Université Bordeaux, Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Bordeaux, France
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Guillot B, Boileve A, Walton R, Harfoush A, Conte C, Sainte-Marie Y, Charron S, Bernus O, Recalde A, Sallé L, Brette F, Lezoualc'h F. Inhibition of EPAC1 signaling pathway alters atrial electrophysiology and prevents atrial fibrillation. Front Physiol 2023; 14:1120336. [PMID: 36909224 PMCID: PMC9992743 DOI: 10.3389/fphys.2023.1120336] [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: 12/09/2022] [Accepted: 02/09/2023] [Indexed: 02/24/2023] Open
Abstract
Introduction: Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and is associated with increased mortality and morbidity. The Exchange Protein directly Activated by cAMP (EPAC), has been implicated in pro-arrhythmic signaling pathways in the atria, but the underlying mechanisms remain unknown. Methods: In this study, we investigated the involvement of EPAC1 and EPAC2 isoforms in the genesis of AF in wild type (WT) mice and knockout (KO) mice for EPAC1 or EPAC2. We also employed EPAC pharmacological modulators to selectively activate EPAC proteins (8-CPT-AM; 10 μM), or inhibit either EPAC1 (AM-001; 20 μM) or EPAC2 (ESI-05; 25 μM). Transesophageal stimulation was used to characterize the induction of AF in vivo in mice. Optical mapping experiments were performed on isolated mouse atria and cellular electrophysiology was examined by whole-cell patch-clamp technique. Results: In wild type mice, we found 8-CPT-AM slightly increased AF susceptibility and that this was blocked by the EPAC1 inhibitor AM-001 but not the EPAC2 inhibitor ESI-05. Consistent with this, in EPAC1 KO mice, occurrence of AF was observed in 3/12 (vs. 4/10 WT littermates) and 4/10 in EPAC2 KO (vs. 5/10 WT littermates). In wild type animals, optical mapping experiments revealed that 8-CPT-AM perfusion increased action potential duration even in the presence of AM-001 or ESI-05. Interestingly, 8-CPT-AM perfusion decreased conduction velocity, an effect blunted by AM-001 but not ESI-05. Patch-clamp experiments demonstrated action potential prolongation after 8-CPT-AM perfusion in both wild type and EPAC1 KO mice and this effect was partially prevented by AM-001 in WT. Conclusion: Together, these results indicate that EPAC1 and EPAC2 signaling pathways differentially alter atrial electrophysiology but only the EPAC1 isoform is involved in the genesis of AF. Selective blockade of EPAC1 with AM-001 prevents AF in mice.
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Affiliation(s)
- Bastien Guillot
- IHU LIRYC -CRCTB U1045, Pessac, France.,INSERM U1045 -Université de Bordeaux, Bordeaux, France
| | - Arthur Boileve
- UR 4650 PSIR, GIP Cyceron, Caen, France.,Université de Caen-Normandie, Caen, France
| | - Richard Walton
- IHU LIRYC -CRCTB U1045, Pessac, France.,INSERM U1045 -Université de Bordeaux, Bordeaux, France
| | - Alexandre Harfoush
- UR 4650 PSIR, GIP Cyceron, Caen, France.,Université de Caen-Normandie, Caen, France
| | - Caroline Conte
- Université de Toulouse-Paul Sabatier, Toulouse, France.,Institut des maladies métaboliques et cardiovasculaires, INSERM UMR-1297, Toulouse, France
| | - Yannis Sainte-Marie
- Université de Toulouse-Paul Sabatier, Toulouse, France.,Institut des maladies métaboliques et cardiovasculaires, INSERM UMR-1297, Toulouse, France
| | - Sabine Charron
- IHU LIRYC -CRCTB U1045, Pessac, France.,INSERM U1045 -Université de Bordeaux, Bordeaux, France
| | - Olivier Bernus
- IHU LIRYC -CRCTB U1045, Pessac, France.,INSERM U1045 -Université de Bordeaux, Bordeaux, France
| | - Alice Recalde
- IHU LIRYC -CRCTB U1045, Pessac, France.,INSERM U1045 -Université de Bordeaux, Bordeaux, France
| | - Laurent Sallé
- UR 4650 PSIR, GIP Cyceron, Caen, France.,Université de Caen-Normandie, Caen, France
| | - Fabien Brette
- IHU LIRYC -CRCTB U1045, Pessac, France.,INSERM U1045 -Université de Bordeaux, Bordeaux, France.,PhyMedExp, INSERM U1046, CNRS 9412, Université de Montpellier, Montpellier, France
| | - Frank Lezoualc'h
- Université de Toulouse-Paul Sabatier, Toulouse, France.,Institut des maladies métaboliques et cardiovasculaires, INSERM UMR-1297, Toulouse, France
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Lamonzie E, Vaillant F, Abell E, Charron S, El Hamrani D, Quesson B, Brette F. Assessment of Cardiac Toxicity of Manganese Chloride for Cardiovascular Magnetic Resonance. Front Physiol 2022; 13:952043. [PMID: 35874541 PMCID: PMC9302587 DOI: 10.3389/fphys.2022.952043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 06/13/2022] [Indexed: 11/13/2022] Open
Abstract
MRI is widely used in cardiology to characterize the structure and function of the heart. Currently, gadolinium-based contrast agents are widely used to improve sensitivity and specificity of diagnostic images. Recently, Manganese, a calcium analogue, has emerged as a complementary contrast agent with the potential to reveal remaining viable cells within altered tissue. Imaging applications may be limited by substantial toxicity of manganese. Indeed, cardiac safety of manganese is not yet comprehensively assessed. In this study we investigated the effect of MnCl2 (1–100 µM) on cardiac function. Hemodynamic function was determined ex vivo using an isolated working rat heart preparation. HL-1 cardiac myocytes were used to investigate cell viability (calcein AM) and calcium cycling (Cal-520 a.m.). Rat ventricular cardiomyocytes were dissociated by enzymatic digestion. Action potentials and calcium currents were recorded using the patch clamp technique. MRI experiments were performed at 1.5T on formalin-fixed rat hearts, previously perfused with MnCl2. MnCl2 perfusion from 1 up to 100 µM in isolated working hearts did not alter left ventricular hemodynamic parameters. Contractility and relaxation index were not altered up to 50 µM MnCl2. In HL-1 cardiac myocytes, incubation with increasing concentrations of MnCl2 did not impact cell viability. The amplitude of the calcium transients were significantly reduced at 50 and 100 µM MnCl2. In freshly isolated ventricular myocytes, action potential duration at 20, 50 and 90% of repolarization were not modified up to 10 µM of MnCl2. L-type calcium current amplitude was significantly decreased by 50 and 100 µM of MnCl2. MRI on heart perfused with 25 and 100 µM of MnCl2 showed a dose dependent decrease in the T1 relaxation time. In conclusion, our results show that low concentrations of MnCl2 (up to 25 µM) can be used as a contrast agent in MRI, without significant impact on cardiac hemodynamic or electrophysiology parameters.
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Affiliation(s)
- Elodie Lamonzie
- Univ, Bordeaux, CRCTB, Inserm, Bordeaux, France
- IHU Liryc, Electrophysiology and Heart Modeling Institute, Bordeaux, France
| | - Fanny Vaillant
- Univ, Bordeaux, CRCTB, Inserm, Bordeaux, France
- IHU Liryc, Electrophysiology and Heart Modeling Institute, Bordeaux, France
| | - Emma Abell
- Univ, Bordeaux, CRCTB, Inserm, Bordeaux, France
- IHU Liryc, Electrophysiology and Heart Modeling Institute, Bordeaux, France
| | | | - Dounia El Hamrani
- Univ, Bordeaux, CRCTB, Inserm, Bordeaux, France
- IHU Liryc, Electrophysiology and Heart Modeling Institute, Bordeaux, France
| | - Bruno Quesson
- Univ, Bordeaux, CRCTB, Inserm, Bordeaux, France
- IHU Liryc, Electrophysiology and Heart Modeling Institute, Bordeaux, France
| | - Fabien Brette
- Univ, Bordeaux, CRCTB, Inserm, Bordeaux, France
- IHU Liryc, Electrophysiology and Heart Modeling Institute, Bordeaux, France
- *Correspondence: Fabien Brette,
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Dubes V, Charron S, Valdeolmillos E, Schena M, Martin A, Hamrani DE, Naulin J, Michel C, Constantin M, Roubertie F, Quesson B, Bernus O, Thambo JB, Jalal Z, Benoist D. Effect of percutaneous pulmonary valve replacement on ventricular electrophysiological remodeling in a porcine model of repaired tetralogy of Fallot. Archives of Cardiovascular Diseases Supplements 2022. [DOI: 10.1016/j.acvdsp.2022.04.103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Magat J, Fouillet A, Constantin M, Haliot K, Naulin J, El Hamrani D, Benoist D, Charron S, Walton R, Bernus O, Quesson B. 3D magnetization transfer (MT) for the visualization of cardiac free-running Purkinje fibers: an ex vivo proof of concept. MAGMA 2021; 34:605-618. [PMID: 33484367 PMCID: PMC8338918 DOI: 10.1007/s10334-020-00905-w] [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] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 12/02/2020] [Accepted: 12/22/2020] [Indexed: 12/26/2022]
Abstract
OBJECTIVES We investigate the possibility to exploit high-field MRI to acquire 3D images of Purkinje network which plays a crucial role in cardiac function. Since Purkinje fibers (PF) have a distinct cellular structure and are surrounded by connective tissue, we investigated conventional contrast mechanisms along with the magnetization transfer (MT) imaging technique to improve image contrast between ventricular structures of differing macromolecular content. METHODS Three fixed porcine ventricular samples were used with free-running PFs on the endocardium. T1, T2*, T2, and M0 were evaluated on 2D slices for each sample at 9.4 T. MT parameters were optimized using hard pulses with different amplitudes, offset frequencies and durations. The cardiac structure was assessed through 2D and 3D T1w images with isotropic resolutions of 150 µm. Histology, immunofluorescence, and qPCR were performed to analyze collagen contents of cardiac tissue and PF. RESULTS An MT preparation module of 350 ms duration inserted into the sequence with a B1 = 10 µT and frequency offset = 3000 Hz showed the best contrast, approximately 0.4 between PFs and myocardium. Magnetization transfer ratio (MTR) appeared higher in the cardiac tissue (MTR = 44.7 ± 3.5%) than in the PFs (MTR = 25.2 ± 6.3%). DISCUSSION MT significantly improves contrast between PFs and ventricular myocardium and appears promising for imaging the 3D architecture of the Purkinje network.
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Affiliation(s)
- Julie Magat
- IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Hopital Xavier Arnozan, Avenue du Haut Lévêque, 33604, Pessac cedex, France.
- Centre de Recherche Cardio-Thoracique de Bordeaux Inserm, U1045, Université de Bordeaux, 33000, Bordeaux, France.
| | - Arnaud Fouillet
- IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Hopital Xavier Arnozan, Avenue du Haut Lévêque, 33604, Pessac cedex, France
- Centre de Recherche Cardio-Thoracique de Bordeaux Inserm, U1045, Université de Bordeaux, 33000, Bordeaux, France
| | - Marion Constantin
- IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Hopital Xavier Arnozan, Avenue du Haut Lévêque, 33604, Pessac cedex, France
- Centre de Recherche Cardio-Thoracique de Bordeaux Inserm, U1045, Université de Bordeaux, 33000, Bordeaux, France
| | - Kylian Haliot
- IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Hopital Xavier Arnozan, Avenue du Haut Lévêque, 33604, Pessac cedex, France
- Centre de Recherche Cardio-Thoracique de Bordeaux Inserm, U1045, Université de Bordeaux, 33000, Bordeaux, France
| | - Jérôme Naulin
- IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Hopital Xavier Arnozan, Avenue du Haut Lévêque, 33604, Pessac cedex, France
- Centre de Recherche Cardio-Thoracique de Bordeaux Inserm, U1045, Université de Bordeaux, 33000, Bordeaux, France
| | - Dounia El Hamrani
- IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Hopital Xavier Arnozan, Avenue du Haut Lévêque, 33604, Pessac cedex, France
- Centre de Recherche Cardio-Thoracique de Bordeaux Inserm, U1045, Université de Bordeaux, 33000, Bordeaux, France
| | - David Benoist
- IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Hopital Xavier Arnozan, Avenue du Haut Lévêque, 33604, Pessac cedex, France
- Centre de Recherche Cardio-Thoracique de Bordeaux Inserm, U1045, Université de Bordeaux, 33000, Bordeaux, France
| | - Sabine Charron
- IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Hopital Xavier Arnozan, Avenue du Haut Lévêque, 33604, Pessac cedex, France
- Centre de Recherche Cardio-Thoracique de Bordeaux Inserm, U1045, Université de Bordeaux, 33000, Bordeaux, France
| | - Richard Walton
- IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Hopital Xavier Arnozan, Avenue du Haut Lévêque, 33604, Pessac cedex, France
- Centre de Recherche Cardio-Thoracique de Bordeaux Inserm, U1045, Université de Bordeaux, 33000, Bordeaux, France
| | - Olivier Bernus
- IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Hopital Xavier Arnozan, Avenue du Haut Lévêque, 33604, Pessac cedex, France
- Centre de Recherche Cardio-Thoracique de Bordeaux Inserm, U1045, Université de Bordeaux, 33000, Bordeaux, France
| | - Bruno Quesson
- IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Hopital Xavier Arnozan, Avenue du Haut Lévêque, 33604, Pessac cedex, France
- Centre de Recherche Cardio-Thoracique de Bordeaux Inserm, U1045, Université de Bordeaux, 33000, Bordeaux, France
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Chaigne S, Cardouat G, Louradour J, Vaillant F, Charron S, Sacher F, Ducret T, Guinamard R, Vigmond E, Hof T. Transient receptor potential vanilloid 4 channel participates in mouse ventricular electrical activity. Am J Physiol Heart Circ Physiol 2021; 320:H1156-H1169. [PMID: 33449852 DOI: 10.1152/ajpheart.00497.2020] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 01/06/2021] [Indexed: 12/25/2022]
Abstract
The TRPV4 channel is a calcium-permeable channel (PCa/PNa ∼ 10). Its expression has been reported in ventricular myocytes, where it is involved in several cardiac pathological mechanisms. In this study, we investigated the implication of TRPV4 in ventricular electrical activity. Left ventricular myocytes were isolated from trpv4+/+ and trpv4-/- mice. TRPV4 membrane expression and its colocalization with L-type calcium channels (Cav1.2) was confirmed using Western blot biotinylation, immunoprecipitation, and immunostaining experiments. Then, electrocardiograms (ECGs) and patch-clamp recordings showed shortened QTc and action potential (AP) duration in trpv4-/- compared with trpv4+/+ mice. Thus, TRPV4 activator GSK1016790A produced a transient and dose-dependent increase in AP duration at 90% of repolarization (APD90) in trpv4+/+ but not in trpv4-/- myocytes or when combined with TRPV4 inhibitor GSK2193874 (100 nM). Hence, GSK1016790A increased calcium transient (CaT) amplitude in trpv4+/+ but not in trpv4-/- myocytes, suggesting that TRPV4 carries an inward Ca2+ current in myocytes. Conversely, TRPV4 inhibitor GSK2193874 (100 nM) alone reduced APD90 in trpv4+/+ but not in trpv4-/- myocytes, suggesting that TRPV4 prolongs AP duration in basal condition. Finally, introducing TRPV4 parameters in a mathematical model predicted the development of an inward TRPV4 current during repolarization that increases AP duration and CaT amplitude, in accord with what was found experimentally. This study shows for the first time that TRPV4 modulates AP and QTc durations. It would be interesting to evaluate whether TRPV4 could be involved in long QT-mediated ventricular arrhythmias.NEW & NOTEWORTHY Transient receptor potential vanilloid 4 (TRPV4) is expressed at the membrane of mouse ventricular myocytes and colocalizes with non-T-tubular L-type calcium channels. Deletion of trpv4 gene in mice results in shortened QT interval on electrocardiogram and reduced action potential duration of ventricular myocytes. Pharmacological activation of TRPV4 channel leads to increased action potential duration and increased calcium transient amplitude in trpv4-/- but not in trpv4-/- ventricular myocytes. To the contrary, TRPV4 channel pharmacological inhibition reduces action potential duration in trpv4+/+ but not in trpv4-/- myocytes. Integration of TRPV4 channel in a computational model of mouse action potential shows that the channel carries an inward current contributing to slowing down action potential repolarization and to increase calcium transient amplitude, similarly to what is observed experimentally. This study highlights for the first time the involvement of TRPV4 channel in ventricular electrical activity.
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Affiliation(s)
- Sebastien Chaigne
- Instituts hospitalo-universitaires, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France
- Electrophysiology and Ablation Unit, Bordeaux University Hospital, Pessac, France
| | - Guillaume Cardouat
- Centre de recherche Cardio-Thoracique de Bordeaux, Institut national de la santé et de la recherche médicale, Bordeaux, France
- Centre de recherche Cardio-Thoracique de Bordeaux, Université Bordeaux, Bordeaux, France
| | - Julien Louradour
- Instituts hospitalo-universitaires, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France
| | - Fanny Vaillant
- Instituts hospitalo-universitaires, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France
| | - Sabine Charron
- Instituts hospitalo-universitaires, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France
- Centre de recherche Cardio-Thoracique de Bordeaux, Institut national de la santé et de la recherche médicale, Bordeaux, France
| | - Frederic Sacher
- Centre de recherche Cardio-Thoracique de Bordeaux, Université Bordeaux, Bordeaux, France
| | - Thomas Ducret
- Centre de recherche Cardio-Thoracique de Bordeaux, Institut national de la santé et de la recherche médicale, Bordeaux, France
- Centre de recherche Cardio-Thoracique de Bordeaux, Université Bordeaux, Bordeaux, France
| | - Romain Guinamard
- Signalisation, Electrophysiologie et Imagerie des lésions d'Ischémie-Reperfusion Myocardique, EA4650 Université Caen Normandie, Caen, France
| | - Edward Vigmond
- Instituts hospitalo-universitaires, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France
- Centre de recherche Cardio-Thoracique de Bordeaux, Université Bordeaux, Bordeaux, France
| | - Thomas Hof
- Instituts hospitalo-universitaires, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France
- Centre de recherche Cardio-Thoracique de Bordeaux, Université Bordeaux, Bordeaux, France
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7
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Dubes V, Benoist D, Roubertie F, Gilbert SH, Constantin M, Charron S, Elbes D, Vieillot D, Quesson B, Cochet H, Haïssaguerre M, Rooryck C, Bordachar P, Thambo JB, Bernus O. Arrhythmogenic Remodeling of the Left Ventricle in a Porcine Model of Repaired Tetralogy of Fallot. Circ Arrhythm Electrophysiol 2019; 11:e006059. [PMID: 30354410 PMCID: PMC6553519 DOI: 10.1161/circep.117.006059] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Supplemental Digital Content is available in the text. Background Ventricular arrhythmias are frequent in patients with repaired tetralogy of Fallot (rTOF), but their origin and underlying mechanisms remain unclear. In this study, the involvement of left ventricular (LV) electrical and structural remodeling was assessed in an animal model mimicking rTOF sequelae. Methods Piglets underwent a tetralogy of Fallot repair–like surgery (n=6) or were sham operated (Sham, n=5). Twenty-three weeks post-surgery, cardiac function was assessed in vivo by magnetic resonance imaging. Electrophysiological properties were characterized by optical mapping. LV fibrosis and connexin-43 localization were assessed on histological sections and protein expression assessed by Western Blot. Results Right ventricular dysfunction was evident, whereas LV function remained unaltered in rTOF pigs. Optical mapping showed longer action potential duration on the rTOF LV epicardium and endocardium. Epicardial conduction velocity was significantly reduced in the longitudinal direction in rTOF LVs but not in the transverse direction compared with Sham. An elevated collagen content was found in LV basal and apical sections from rTOF pigs. Moreover, a trend for connexin-43 lateralization with no change in protein expression was found in the LV of rTOFs. Finally, rTOF LVs had a lower threshold for arrhythmia induction using incremental pacing protocols. Conclusions We found an arrhythmogenic substrate with prolonged heterogeneous action potential duration and reduced conduction velocity in the LV of rTOF pigs. This remodeling precedes LV dysfunction and is likely to contribute to ventricular arrhythmias and sudden cardiac death in patients with rTOF.
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Affiliation(s)
- Virginie Dubes
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Pessac, France (V.D., D.B., F.R., S.H.G., M.C., S.C., D.E., B.Q., H.C., M.H., C.R., P.B., J.-B.T., O.B.).,Inserm U1045, Centre de Recherche Cardio-Thoracique de Bordeaux, Université de Bordeaux, France. (V.D., D.B., F.R., S.H.G., M.C., S.C., D.E., B.Q., H.C., M.H., P.B., J.-B.T., O.B.)
| | - David Benoist
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Pessac, France (V.D., D.B., F.R., S.H.G., M.C., S.C., D.E., B.Q., H.C., M.H., C.R., P.B., J.-B.T., O.B.).,Inserm U1045, Centre de Recherche Cardio-Thoracique de Bordeaux, Université de Bordeaux, France. (V.D., D.B., F.R., S.H.G., M.C., S.C., D.E., B.Q., H.C., M.H., P.B., J.-B.T., O.B.)
| | - François Roubertie
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Pessac, France (V.D., D.B., F.R., S.H.G., M.C., S.C., D.E., B.Q., H.C., M.H., C.R., P.B., J.-B.T., O.B.).,Inserm U1045, Centre de Recherche Cardio-Thoracique de Bordeaux, Université de Bordeaux, France. (V.D., D.B., F.R., S.H.G., M.C., S.C., D.E., B.Q., H.C., M.H., P.B., J.-B.T., O.B.).,Centre Hospitalier Universitaire de Bordeaux, Hôpital Cardiologique du Haut-Lévêque, Pessac, France (F.R., H.C., M.H., C.R., P.B., J.-B.T.)
| | - Stephen H Gilbert
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Pessac, France (V.D., D.B., F.R., S.H.G., M.C., S.C., D.E., B.Q., H.C., M.H., C.R., P.B., J.-B.T., O.B.).,Inserm U1045, Centre de Recherche Cardio-Thoracique de Bordeaux, Université de Bordeaux, France. (V.D., D.B., F.R., S.H.G., M.C., S.C., D.E., B.Q., H.C., M.H., P.B., J.-B.T., O.B.).,Max Delbröck Center for Molecular Medicine, Berlin, Germany (S.H.G.)
| | - Marion Constantin
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Pessac, France (V.D., D.B., F.R., S.H.G., M.C., S.C., D.E., B.Q., H.C., M.H., C.R., P.B., J.-B.T., O.B.).,Inserm U1045, Centre de Recherche Cardio-Thoracique de Bordeaux, Université de Bordeaux, France. (V.D., D.B., F.R., S.H.G., M.C., S.C., D.E., B.Q., H.C., M.H., P.B., J.-B.T., O.B.)
| | - Sabine Charron
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Pessac, France (V.D., D.B., F.R., S.H.G., M.C., S.C., D.E., B.Q., H.C., M.H., C.R., P.B., J.-B.T., O.B.).,Inserm U1045, Centre de Recherche Cardio-Thoracique de Bordeaux, Université de Bordeaux, France. (V.D., D.B., F.R., S.H.G., M.C., S.C., D.E., B.Q., H.C., M.H., P.B., J.-B.T., O.B.)
| | - Delphine Elbes
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Pessac, France (V.D., D.B., F.R., S.H.G., M.C., S.C., D.E., B.Q., H.C., M.H., C.R., P.B., J.-B.T., O.B.).,Inserm U1045, Centre de Recherche Cardio-Thoracique de Bordeaux, Université de Bordeaux, France. (V.D., D.B., F.R., S.H.G., M.C., S.C., D.E., B.Q., H.C., M.H., P.B., J.-B.T., O.B.).,Institute of Biomedical Engineering, University of Oxford, United Kingdom (D.E.)
| | - Delphine Vieillot
- Plateforme Technologique d'Innovation Biomédicale, Université de Bordeaux, France. (D.V.)
| | - Bruno Quesson
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Pessac, France (V.D., D.B., F.R., S.H.G., M.C., S.C., D.E., B.Q., H.C., M.H., C.R., P.B., J.-B.T., O.B.).,Inserm U1045, Centre de Recherche Cardio-Thoracique de Bordeaux, Université de Bordeaux, France. (V.D., D.B., F.R., S.H.G., M.C., S.C., D.E., B.Q., H.C., M.H., P.B., J.-B.T., O.B.)
| | - Hubert Cochet
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Pessac, France (V.D., D.B., F.R., S.H.G., M.C., S.C., D.E., B.Q., H.C., M.H., C.R., P.B., J.-B.T., O.B.).,Inserm U1045, Centre de Recherche Cardio-Thoracique de Bordeaux, Université de Bordeaux, France. (V.D., D.B., F.R., S.H.G., M.C., S.C., D.E., B.Q., H.C., M.H., P.B., J.-B.T., O.B.).,Centre Hospitalier Universitaire de Bordeaux, Hôpital Cardiologique du Haut-Lévêque, Pessac, France (F.R., H.C., M.H., C.R., P.B., J.-B.T.)
| | - Michel Haïssaguerre
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Pessac, France (V.D., D.B., F.R., S.H.G., M.C., S.C., D.E., B.Q., H.C., M.H., C.R., P.B., J.-B.T., O.B.).,Inserm U1045, Centre de Recherche Cardio-Thoracique de Bordeaux, Université de Bordeaux, France. (V.D., D.B., F.R., S.H.G., M.C., S.C., D.E., B.Q., H.C., M.H., P.B., J.-B.T., O.B.).,Centre Hospitalier Universitaire de Bordeaux, Hôpital Cardiologique du Haut-Lévêque, Pessac, France (F.R., H.C., M.H., C.R., P.B., J.-B.T.)
| | - Caroline Rooryck
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Pessac, France (V.D., D.B., F.R., S.H.G., M.C., S.C., D.E., B.Q., H.C., M.H., C.R., P.B., J.-B.T., O.B.).,Inserm U1211, Maladies Rares: Génétique et Métabolisme, Université de Bordeaux, France. (C.R.).,Centre Hospitalier Universitaire de Bordeaux, Hôpital Cardiologique du Haut-Lévêque, Pessac, France (F.R., H.C., M.H., C.R., P.B., J.-B.T.)
| | - Pierre Bordachar
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Pessac, France (V.D., D.B., F.R., S.H.G., M.C., S.C., D.E., B.Q., H.C., M.H., C.R., P.B., J.-B.T., O.B.).,Inserm U1045, Centre de Recherche Cardio-Thoracique de Bordeaux, Université de Bordeaux, France. (V.D., D.B., F.R., S.H.G., M.C., S.C., D.E., B.Q., H.C., M.H., P.B., J.-B.T., O.B.).,Centre Hospitalier Universitaire de Bordeaux, Hôpital Cardiologique du Haut-Lévêque, Pessac, France (F.R., H.C., M.H., C.R., P.B., J.-B.T.)
| | - Jean-Benoit Thambo
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Pessac, France (V.D., D.B., F.R., S.H.G., M.C., S.C., D.E., B.Q., H.C., M.H., C.R., P.B., J.-B.T., O.B.).,Inserm U1045, Centre de Recherche Cardio-Thoracique de Bordeaux, Université de Bordeaux, France. (V.D., D.B., F.R., S.H.G., M.C., S.C., D.E., B.Q., H.C., M.H., P.B., J.-B.T., O.B.).,Centre Hospitalier Universitaire de Bordeaux, Hôpital Cardiologique du Haut-Lévêque, Pessac, France (F.R., H.C., M.H., C.R., P.B., J.-B.T.)
| | - Olivier Bernus
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Pessac, France (V.D., D.B., F.R., S.H.G., M.C., S.C., D.E., B.Q., H.C., M.H., C.R., P.B., J.-B.T., O.B.).,Inserm U1045, Centre de Recherche Cardio-Thoracique de Bordeaux, Université de Bordeaux, France. (V.D., D.B., F.R., S.H.G., M.C., S.C., D.E., B.Q., H.C., M.H., P.B., J.-B.T., O.B.)
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Chaigne S, Louradour J, Charron S, Brette F, Ducret T, Hof T. Transient Receptor Potential Vanilloid 4 channels participate in mouse ventricular action potentia. Archives of Cardiovascular Diseases Supplements 2019. [DOI: 10.1016/j.acvdsp.2019.02.165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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9
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Dubes V, Charron S, Michel C, Constantin M, Haissaguerre M, Hocini M, Bernus O, Benoist D. Regional β-adrenergic regulation of action potential duration and arrhythmias in the pig right ventricle. Archives of Cardiovascular Diseases Supplements 2018. [DOI: 10.1016/j.acvdsp.2018.02.141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Mahdjoub E, Turc G, Legrand L, Benzakoun J, Edjlali M, Seners P, Charron S, Ben Hassen W, Naggara O, Meder JF, Mas JL, Baron JC, Oppenheim C. Do Fluid-Attenuated Inversion Recovery Vascular Hyperintensities Represent Good Collaterals before Reperfusion Therapy? AJNR Am J Neuroradiol 2017; 39:77-83. [PMID: 29074634 DOI: 10.3174/ajnr.a5431] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 08/24/2017] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE In acute ischemic stroke, whether FLAIR vascular hyperintensities represent good or poor collaterals remains controversial. We hypothesized that extensive FLAIR vascular hyperintensities correspond to good collaterals, as indirectly assessed by the hypoperfusion intensity ratio. MATERIALS AND METHODS We included 244 consecutive patients eligible for reperfusion therapy with MCA stroke and pretreatment MR imaging with both FLAIR and PWI. The FLAIR vascular hyperintensity score was based on ASPECTS, ranging from 0 (no FLAIR vascular hyperintensity) to 7 (FLAIR vascular hyperintensities abutting all ASPECTS cortical areas). The hypoperfusion intensity ratio was defined as the ratio of the time-to-maximum >10-second over time-to-maximum >6-second lesion volumes. The median hypoperfusion intensity ratio was used to dichotomize good (low hypoperfusion intensity ratio) versus poor (high hypoperfusion intensity ratio) collaterals. We then studied the association between FLAIR vascular hyperintensity extent and hypoperfusion intensity ratio. RESULTS Hypoperfusion was present in all patients, with a median hypoperfusion intensity ratio of 0.35 (interquartile range, 0.19-0.48). The median FLAIR vascular hyperintensity score was 4 (interquartile range, 3-5). The FLAIR vascular hyperintensities were more extensive in patients with good collaterals (hypoperfusion intensity ratio ≤0.35) than with poor collaterals (hypoperfusion intensity ratio >0.35; P for Trend = .016). The FLAIR vascular hyperintensity score was independently associated with good collaterals (P for Trend = .002). CONCLUSIONS In patients eligible for reperfusion therapy, FLAIR vascular hyperintensity extent was associated with good collaterals, as assessed by the pretreatment hypoperfusion intensity ratio. The ASPECTS assessment of FLAIR vascular hyperintensities could be used to rapidly identify patients more likely to benefit from reperfusion therapy.
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Affiliation(s)
- E Mahdjoub
- From the Departments of Radiology (E.M., L.L., J.B., M.E., S.C., W.B.H., O.N., J.-F.M., C.O.)
| | - G Turc
- Neurology (G.T., P.S., J.-L.M., J.-C.B.), Université Paris Descartes, Institut national de la santé et de la recherche médicale S894, Département Hospitalo-Universitaire Neurovasc, Centre Hospitalier Sainte-Anne, Paris, France
| | - L Legrand
- From the Departments of Radiology (E.M., L.L., J.B., M.E., S.C., W.B.H., O.N., J.-F.M., C.O.)
| | - J Benzakoun
- From the Departments of Radiology (E.M., L.L., J.B., M.E., S.C., W.B.H., O.N., J.-F.M., C.O.)
| | - M Edjlali
- From the Departments of Radiology (E.M., L.L., J.B., M.E., S.C., W.B.H., O.N., J.-F.M., C.O.)
| | - P Seners
- Neurology (G.T., P.S., J.-L.M., J.-C.B.), Université Paris Descartes, Institut national de la santé et de la recherche médicale S894, Département Hospitalo-Universitaire Neurovasc, Centre Hospitalier Sainte-Anne, Paris, France
| | - S Charron
- From the Departments of Radiology (E.M., L.L., J.B., M.E., S.C., W.B.H., O.N., J.-F.M., C.O.)
| | - W Ben Hassen
- From the Departments of Radiology (E.M., L.L., J.B., M.E., S.C., W.B.H., O.N., J.-F.M., C.O.)
| | - O Naggara
- From the Departments of Radiology (E.M., L.L., J.B., M.E., S.C., W.B.H., O.N., J.-F.M., C.O.)
| | - J-F Meder
- From the Departments of Radiology (E.M., L.L., J.B., M.E., S.C., W.B.H., O.N., J.-F.M., C.O.)
| | - J-L Mas
- Neurology (G.T., P.S., J.-L.M., J.-C.B.), Université Paris Descartes, Institut national de la santé et de la recherche médicale S894, Département Hospitalo-Universitaire Neurovasc, Centre Hospitalier Sainte-Anne, Paris, France
| | - J-C Baron
- Neurology (G.T., P.S., J.-L.M., J.-C.B.), Université Paris Descartes, Institut national de la santé et de la recherche médicale S894, Département Hospitalo-Universitaire Neurovasc, Centre Hospitalier Sainte-Anne, Paris, France
| | - C Oppenheim
- From the Departments of Radiology (E.M., L.L., J.B., M.E., S.C., W.B.H., O.N., J.-F.M., C.O.)
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Mellerio C, Charron S, Lion S, Roca P, Kuchcinski G, Legrand L, Edjlali M, Naggara O, Meder JF, Pallud J, Oppenheim C. Perioperative functional neuroimaging of gliomas in eloquent brain areas. Neurochirurgie 2017; 63:129-134. [DOI: 10.1016/j.neuchi.2016.10.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 10/10/2016] [Accepted: 10/31/2016] [Indexed: 11/25/2022]
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Dubes V, Magat J, Constantin M, Charron S, Ozenne V, Gilbert S, Vaillant F, Cros C, Dupuis S, Faye R, Pourtau L, Brette F, Chaigne S, Detaille D, Guo Y, Walton R, Diolez P, Desplantez T, Pascarel-Auclerc C, Pasdois P, Martinez M, Haissaguerre M, Hocini M, Coronel R, Quesson B, Bernus O, Benoist D. Specific tissue structure of the right ventricular outflow tract as a substrate for arrhythmias. Archives of Cardiovascular Diseases Supplements 2017. [DOI: 10.1016/s1878-6480(17)30496-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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13
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Guo Y, Chaigne S, Charron S, Bru-Mercier G, Bernus O, Hocini M, Haissaguerre M, Cros C, Brette F, Stuyvers B. Remodelling of intracellular Ca 2+ uptake in cardiac Purkinje cells; a possible origin for the triggers of ventricular tachycardias associated with myocardial ischemia. Archives of Cardiovascular Diseases Supplements 2017. [DOI: 10.1016/s1878-6480(17)30415-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Trimouille A, Barouk-Simonet E, Charron S, Bouron J, Bernhard JC, Lacombe D, Fergelot P, Rooryck C. Deletion of the transcription factor SOX4 is implicated in syndromic nephroblastoma. Clin Genet 2017; 92:449-450. [PMID: 28303571 DOI: 10.1111/cge.12977] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 01/20/2017] [Accepted: 01/23/2017] [Indexed: 02/04/2023]
Affiliation(s)
- A Trimouille
- CHU Bordeaux, Service de Génétique Médicale, Bordeaux, France
| | - E Barouk-Simonet
- Pathology and Genetics Department, Institut Bergonié, Bordeaux, France
| | - S Charron
- University Bordeaux, INSERM U 1211 - Maladies Rares, Génétique et Métabolisme (MRGM), Bordeaux, France
| | - J Bouron
- CHU Bordeaux, Service de Génétique Médicale, Bordeaux, France
| | - J-C Bernhard
- CHU Bordeaux, Service d'Urologie, Bordeaux, France
| | - D Lacombe
- CHU Bordeaux, Service de Génétique Médicale, Bordeaux, France.,University Bordeaux, INSERM U 1211 - Maladies Rares, Génétique et Métabolisme (MRGM), Bordeaux, France
| | - P Fergelot
- CHU Bordeaux, Service de Génétique Médicale, Bordeaux, France.,University Bordeaux, INSERM U 1211 - Maladies Rares, Génétique et Métabolisme (MRGM), Bordeaux, France
| | - C Rooryck
- CHU Bordeaux, Service de Génétique Médicale, Bordeaux, France.,University Bordeaux, INSERM U 1211 - Maladies Rares, Génétique et Métabolisme (MRGM), Bordeaux, France
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15
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Stuyvers B, Boyden P, ter Keurs HEDJ, Guo Y, Dun W, Haq K, Hocini M, Haissaguerre M, Bernus O, Chaigne S, Charron S, Cros C, Brette F. Increased Density of SERCA Pumps at the Periphery of Cardiac Purkinje Cells after Myocardial Infarction. Biophys J 2017. [DOI: 10.1016/j.bpj.2016.11.550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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16
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Benoist D, Dubes V, Roubertie F, Gilbert SH, Charron S, Constantin M, Elbes D, Vieillot D, Quesson B, Cochet H, Haïssaguerre M, Rooryck C, Bordachar P, Thambo JB, Bernus O. Proarrhythmic remodelling of the right ventricle in a porcine model of repaired tetralogy of Fallot. Heart 2016; 103:347-354. [PMID: 28051771 PMCID: PMC5529985 DOI: 10.1136/heartjnl-2016-309730] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Revised: 06/27/2016] [Accepted: 07/21/2016] [Indexed: 11/17/2022] Open
Abstract
Objective The growing adult population with surgically corrected tetralogy of Fallot (TOF) is at risk of arrhythmias and sudden cardiac death. We sought to investigate the contribution of right ventricular (RV) structural and electrophysiological remodelling to arrhythmia generation in a preclinical animal model of repaired TOF (rTOF). Methods and results Pigs mimicking rTOF underwent cardiac MRI functional characterisation and presented with pulmonary regurgitation, RV hypertrophy, dilatation and dysfunction compared with Sham-operated animals (Sham). Optical mapping of rTOF RV-perfused wedges revealed a significant prolongation of RV activation time with slower conduction velocities and regions of conduction slowing well beyond the surgical scar. A reduced protein expression and lateralisation of Connexin-43 were identified in rTOF RVs. A remodelling of extracellular matrix-related gene expression and an increase in collagen content that correlated with prolonged RV activation time were also found in these animals. RV action potential duration (APD) was prolonged in the epicardial anterior region at early and late repolarisation level, thus contributing to a greater APD heterogeneity and to altered transmural and anteroposterior APD gradients in rTOF RVs. APD remodelling involved changes in Kv4.3 and MiRP1 expression. Spontaneous arrhythmias were more frequent in rTOF wedges and more complex in the anterior than in the posterior RV. Conclusion Significant remodelling of RV conduction and repolarisation properties was found in pigs with rTOF. This remodelling generates a proarrhythmic substrate likely to facilitate re-entries and to contribute to sudden cardiac death in patients with rTOF.
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Affiliation(s)
- David Benoist
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France.,Inserm U1045, Centre de Recherche Cardio-Thoracique de Bordeaux, Université de Bordeaux, Bordeaux, France
| | - Virginie Dubes
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France.,Inserm U1045, Centre de Recherche Cardio-Thoracique de Bordeaux, Université de Bordeaux, Bordeaux, France
| | - François Roubertie
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France.,Inserm U1045, Centre de Recherche Cardio-Thoracique de Bordeaux, Université de Bordeaux, Bordeaux, France.,CHU de Bordeaux, Hôpital Cardiologique du Haut-Lévêque, Pessac, France
| | - Stephen H Gilbert
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France.,Inserm U1045, Centre de Recherche Cardio-Thoracique de Bordeaux, Université de Bordeaux, Bordeaux, France.,Max Delbrück Center for Molecular Medicine, Mathematical Cell Physiology, Berlin, Germany
| | - Sabine Charron
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France.,Inserm U1045, Centre de Recherche Cardio-Thoracique de Bordeaux, Université de Bordeaux, Bordeaux, France
| | - Marion Constantin
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France.,Inserm U1045, Centre de Recherche Cardio-Thoracique de Bordeaux, Université de Bordeaux, Bordeaux, France
| | - Delphine Elbes
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France.,Inserm U1045, Centre de Recherche Cardio-Thoracique de Bordeaux, Université de Bordeaux, Bordeaux, France.,Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, UK
| | - Delphine Vieillot
- Plateforme Technologique d'Innovation Biomédicale, Université de Bordeaux, Pessac, France
| | - Bruno Quesson
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France.,Inserm U1045, Centre de Recherche Cardio-Thoracique de Bordeaux, Université de Bordeaux, Bordeaux, France
| | - Hubert Cochet
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France.,Inserm U1045, Centre de Recherche Cardio-Thoracique de Bordeaux, Université de Bordeaux, Bordeaux, France.,CHU de Bordeaux, Hôpital Cardiologique du Haut-Lévêque, Pessac, France
| | - Michel Haïssaguerre
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France.,Inserm U1045, Centre de Recherche Cardio-Thoracique de Bordeaux, Université de Bordeaux, Bordeaux, France.,CHU de Bordeaux, Hôpital Cardiologique du Haut-Lévêque, Pessac, France
| | - Caroline Rooryck
- Inserm U1211, Maladies Rares: Génétique et Métabolisme, Université de Bordeaux, Bordeaux, France
| | - Pierre Bordachar
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France.,Inserm U1045, Centre de Recherche Cardio-Thoracique de Bordeaux, Université de Bordeaux, Bordeaux, France.,CHU de Bordeaux, Hôpital Cardiologique du Haut-Lévêque, Pessac, France
| | - Jean-Benoit Thambo
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France.,Inserm U1045, Centre de Recherche Cardio-Thoracique de Bordeaux, Université de Bordeaux, Bordeaux, France.,CHU de Bordeaux, Hôpital Cardiologique du Haut-Lévêque, Pessac, France
| | - Olivier Bernus
- IHU LIRYC, L'Institut de Rythmologie et Modélisation Cardiaque, Fondation Bordeaux Université, Bordeaux, France.,Inserm U1045, Centre de Recherche Cardio-Thoracique de Bordeaux, Université de Bordeaux, Bordeaux, France
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Lopez E, Berenguer M, Tingaud-Sequeira A, Marlin S, Toutain A, Denoyelle F, Picard A, Charron S, Mathieu G, de Belvalet H, Arveiler B, Babin PJ, Lacombe D, Rooryck C. Mutations in MYT1, encoding the myelin transcription factor 1, are a rare cause of OAVS. J Med Genet 2016; 53:752-760. [PMID: 27358179 DOI: 10.1136/jmedgenet-2016-103774] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [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: 01/12/2016] [Revised: 05/26/2016] [Accepted: 06/01/2016] [Indexed: 01/09/2023]
Abstract
BACKGROUND Oculo-auriculo-vertebral spectrum (OAVS) is a developmental disorder involving first and second branchial arches derivatives, mainly characterised by asymmetric ear anomalies, hemifacial microsomia, ocular defects and vertebral malformations. Although numerous chromosomal abnormalities have been associated with OAVS, no causative gene has been identified so far. OBJECTIVES We aimed to identify the first causative gene for OAVS. METHODS As sporadic cases are mostly described in Goldenhar syndrome, we have performed whole exome sequencing (WES) on selected affected individuals and their unaffected parents, looking for de novo mutations. Candidate gene was tested through transient knockdown experiment in zebrafish using a morpholino-based approach. A functional test was developed in cell culture in order to assess deleterious consequences of mutations. RESULTS By WES, we identified a heterozygous nonsense mutation in one patient in the myelin transcription factor 1 (MYT1) gene. Further, we detected one heterozygous missense mutation in another patient among a cohort of 169 patients with OAVS. This gene encodes the MYT1. Functional studies by transient knockdown of myt1a, homologue of MYT1 in zebrafish, led to specific craniofacial cartilage alterations. Treatment with all-trans retinoic acid (RA), a known teratogenic agent causing OAVS, led to an upregulation of cellular endogenous MYT1 expression. Additionally, cellular wild-type MYT1 overexpression induced a downregulation of RA receptor β (RARB), whereas mutated MYT1 did not. CONCLUSION We report MYT1 as the first gene implicated in OAVS, within the RA signalling pathway.
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Affiliation(s)
- Estelle Lopez
- University of Bordeaux, Maladies Rares: Génétique et Métabolisme (MRGM), U 1211 INSERM, Bordeaux, France
| | - Marie Berenguer
- University of Bordeaux, Maladies Rares: Génétique et Métabolisme (MRGM), U 1211 INSERM, Bordeaux, France
| | - Angèle Tingaud-Sequeira
- University of Bordeaux, Maladies Rares: Génétique et Métabolisme (MRGM), U 1211 INSERM, Bordeaux, France
| | - Sandrine Marlin
- Département de Génétique, Hôpital Universitaire Necker-Enfants-Malades, Centre de Référence des Surdités Génétiques, Paris, France
| | - Annick Toutain
- Service de Génétique, Hôpital Bretonneau, Centre Hospitalier Universitaire, Tours, France
| | - Françoise Denoyelle
- Service d'ORL pédiatrique et de chirurgie cervicofaciale, Hôpital Universitaire Necker-Enfants-Malades, Centre de Référence des malformations ORL rares, Paris, France
| | - Arnaud Picard
- Service de chirurgie maxillo-faciale, Hôpital Universitaire Necker-Enfants Malades, Paris, France
| | - Sabine Charron
- University of Bordeaux, Maladies Rares: Génétique et Métabolisme (MRGM), U 1211 INSERM, Bordeaux, France
| | - Guilaine Mathieu
- University of Bordeaux, Maladies Rares: Génétique et Métabolisme (MRGM), U 1211 INSERM, Bordeaux, France
| | - Harmony de Belvalet
- University of Bordeaux, Maladies Rares: Génétique et Métabolisme (MRGM), U 1211 INSERM, Bordeaux, France
| | - Benoit Arveiler
- University of Bordeaux, Maladies Rares: Génétique et Métabolisme (MRGM), U 1211 INSERM, Bordeaux, France.,Service de Génétique Médicale, CHU de Bordeaux, Centre de Référence Anomalies du Développement et Syndromes Malformatifs, Bordeaux, France
| | - Patrick J Babin
- University of Bordeaux, Maladies Rares: Génétique et Métabolisme (MRGM), U 1211 INSERM, Bordeaux, France
| | - Didier Lacombe
- University of Bordeaux, Maladies Rares: Génétique et Métabolisme (MRGM), U 1211 INSERM, Bordeaux, France.,Service de Génétique Médicale, CHU de Bordeaux, Centre de Référence Anomalies du Développement et Syndromes Malformatifs, Bordeaux, France
| | - Caroline Rooryck
- University of Bordeaux, Maladies Rares: Génétique et Métabolisme (MRGM), U 1211 INSERM, Bordeaux, France.,Service de Génétique Médicale, CHU de Bordeaux, Centre de Référence Anomalies du Développement et Syndromes Malformatifs, Bordeaux, France
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18
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Adachi N, Adamovitch V, Adjovi Y, Aida K, Akamatsu H, Akiyama S, Akli A, Ando A, Andrault T, Antonietti H, Anzai S, Arkoun G, Avenoso C, Ayrault D, Banasiewicz M, Banaśkiewicz M, Bernardini L, Bernard E, Berthet E, Blanchard M, Boreyko D, Boros K, Charron S, Cornette P, Czerkas K, Dameron M, Date I, De Pontbriand M, Demangeau F, Dobaczewski Ł, Dobrzyński L, Ducouret A, Dziedzic M, Ecalle A, Edon V, Endo K, Endo T, Endo Y, Etryk D, Fabiszewska M, Fang S, Fauchier D, Felici F, Fujiwara Y, Gardais C, Gaul W, Gurin L, Hakoda R, Hamamatsu I, Handa K, Haneda H, Hara T, Hashimoto M, Hashimoto T, Hashimoto K, Hata D, Hattori M, Hayano R, Hayashi R, Higasi H, Hiruta M, Honda A, Horikawa Y, Horiuchi H, Hozumi Y, Ide M, Ihara S, Ikoma T, Inohara Y, Itazu M, Ito A, Janvrin J, Jout I, Kanda H, Kanemori G, Kanno M, Kanomata N, Kato T, Kato S, Katsu J, Kawasaki Y, Kikuchi K, Kilian P, Kimura N, Kiya M, Klepuszewski M, Kluchnikov E, Kodama Y, Kokubun R, Konishi F, Konno A, Kontsevoy V, Koori A, Koutaka A, Kowol A, Koyama Y, Kozioł M, Kozue M, Kravtchenko O, Kruczała W, Kudła M, Kudo H, Kumagai R, Kurogome K, Kurosu A, Kuse M, Lacombe A, Lefaillet E, Magara M, Malinowska J, Malinowski M, Maroselli V, Masui Y, Matsukawa K, Matsuya K, Matusik B, Maulny M, Mazur P, Miyake C, Miyamoto Y, Miyata K, Miyata K, Miyazaki M, Molȩda M, Morioka T, Morita E, Muto K, Nadamoto H, Nadzikiewicz M, Nagashima K, Nakade M, Nakayama C, Nakazawa H, Nihei Y, Nikul R, Niwa S, Niwa O, Nogi M, Nomura K, Ogata D, Ohguchi H, Ohno J, Okabe M, Okada M, Okada Y, Omi N, Onodera H, Onodera K, Ooki S, Oonishi K, Oonuma H, Ooshima H, Oouchi H, Orsucci M, Paoli M, Penaud M, Perdrisot C, Petit M, Piskowski A, Płocharski A, Polis A, Polti L, Potsepnia T, Przybylski D, Pytel M, Quillet W, Remy A, Robert C, Sadowski M, Saito M, Sakuma D, Sano K, Sasaki Y, Sato N, Schneider T, Schneider C, Schwartzman K, Selivanov E, Sezaki M, Shiroishi K, Shustava I, Śniecińska A, Stalchenko E, Staroń A, Stromboni M, Studzińska W, Sugisaki H, Sukegawa T, Sumida M, Suzuki Y, Suzuki K, Suzuki R, Suzuki H, Suzuki K, Świderski W, Szudejko M, Szymaszek M, Tada J, Taguchi H, Takahashi K, Tanaka D, Tanaka G, Tanaka S, Tanino K, Tazbir K, Tcesnokova N, Tgawa N, Toda N, Tsuchiya H, Tsukamoto H, Tsushima T, Tsutsumi K, Umemura H, Uno M, Usui A, Utsumi H, Vaucelle M, Wada Y, Watanabe K, Watanabe S, Watase K, Witkowski M, Yamaki T, Yamamoto J, Yamamoto T, Yamashita M, Yanai M, Yasuda K, Yoshida Y, Yoshida A, Yoshimura K, Żmijewska M, Zuclarelli E. Measurement and comparison of individual external doses of high-school students living in Japan, France, Poland and Belarus-the 'D-shuttle' project. J Radiol Prot 2016; 36:49-66. [PMID: 26613195 DOI: 10.1088/0952-4746/36/1/49] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Twelve high schools in Japan (of which six are in Fukushima Prefecture), four in France, eight in Poland and two in Belarus cooperated in the measurement and comparison of individual external doses in 2014. In total 216 high-school students and teachers participated in the study. Each participant wore an electronic personal dosimeter 'D-shuttle' for two weeks, and kept a journal of his/her whereabouts and activities. The distributions of annual external doses estimated for each region overlap with each other, demonstrating that the personal external individual doses in locations where residence is currently allowed in Fukushima Prefecture and in Belarus are well within the range of estimated annual doses due to the terrestrial background radiation level of other regions/countries.
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Affiliation(s)
- N Adachi
- Adachi High School, 2-347 Kakunai, Nihonmatsu, Fukushima 964-0904, Japan
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Dubes V, Charron S, Belterman C, Rooryck-Thambo C, White E, Haissaguerre M, Coronel R, Bernus O, Benoist D. 0298 : Action potential shortening in the pig right ventricular outflow tract epicardium. Archives of Cardiovascular Diseases Supplements 2015. [DOI: 10.1016/s1878-6480(15)30098-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Benoist D, Dubes V, Charron S, Gilbert S, Belterman C, Constantin M, Naulin J, Magat J, Ozenne V, Rooryck-Thambo C, Quesson B, Haïssaguerre M, Coronel R, Bernus O. 0305 : Heterogeneous conduction properties in the pig right ventricle. Archives of Cardiovascular Diseases Supplements 2015. [DOI: 10.1016/s1878-6480(15)30085-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Roubertie F, Dubes V, Benoist D, Gilbert S, Constantin M, Elbes D, Vieillot D, Charron S, Cochet H, Quesson B, Rooryck-Thambo C, Haissaguerre M, Bordachar P, Bernus O, Thambo JB. 0244: Pro-arrhythmic ventricular remodeling in a porcine model of repaired tetralogy of Fallot. Archives of Cardiovascular Diseases Supplements 2015. [DOI: 10.1016/s1878-6480(15)71774-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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22
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Gabriel F, Accoceberry I, Bessoule JF, Manon S, Charron S, Albac S, Dementhon K, Noel T. La β-oxydation chez la levure pathogène opportuniste Candida lusitaniae : existence d’une voie mitochondriale fox2-dépendante et mise en évidence d’une voie peroxysomale alternative fox2-indépendante de catabolisme des acides gras. J Mycol Med 2012. [DOI: 10.1016/j.mycmed.2012.07.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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23
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Fauconnier M, Palomo J, Bourigault ML, Meme S, Szeremeta F, Beloeil JC, Danneels A, Charron S, Rihet P, Ryffel B, Quesniaux VFJ. IL-12Rβ2 Is Essential for the Development of Experimental Cerebral Malaria. J I 2012; 188:1905-14. [DOI: 10.4049/jimmunol.1101978] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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24
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Gasse P, Riteau N, Vacher R, Michel ML, Fautrel A, di Padova F, Fick L, Charron S, Lagente V, Eberl G, Le Bert M, Quesniaux VFJ, Huaux F, Leite-de-Moraes M, Ryffel B, Couillin I. IL-1 and IL-23 mediate early IL-17A production in pulmonary inflammation leading to late fibrosis. PLoS One 2011; 6:e23185. [PMID: 21858022 PMCID: PMC3156735 DOI: 10.1371/journal.pone.0023185] [Citation(s) in RCA: 158] [Impact Index Per Article: 12.2] [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: 04/07/2011] [Accepted: 07/08/2011] [Indexed: 01/25/2023] Open
Abstract
Background Idiopathic pulmonary fibrosis is a devastating as yet untreatable disease. We demonstrated recently the predominant role of the NLRP3 inflammasome activation and IL-1β expression in the establishment of pulmonary inflammation and fibrosis in mice. Methods The contribution of IL-23 or IL-17 in pulmonary inflammation and fibrosis was assessed using the bleomycin model in deficient mice. Results We show that bleomycin or IL-1β-induced lung injury leads to increased expression of early IL-23p19, and IL-17A or IL-17F expression. Early IL-23p19 and IL-17A, but not IL-17F, and IL-17RA signaling are required for inflammatory response to BLM as shown with gene deficient mice or mice treated with neutralizing antibodies. Using FACS analysis, we show a very early IL-17A and IL-17F expression by RORγt+ γδ T cells and to a lesser extent by CD4αβ+ T cells, but not by iNKT cells, 24 hrs after BLM administration. Moreover, IL-23p19 and IL-17A expressions or IL-17RA signaling are necessary to pulmonary TGF-β1 production, collagen deposition and evolution to fibrosis. Conclusions Our findings demonstrate the existence of an early IL-1β-IL-23-IL-17A axis leading to pulmonary inflammation and fibrosis and identify innate IL-23 and IL-17A as interesting drug targets for IL-1β driven lung pathology.
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Affiliation(s)
- Paméla Gasse
- University of Orleans and CNRS, UMR6218, Orleans, France
| | - Nicolas Riteau
- University of Orleans and CNRS, UMR6218, Orleans, France
| | - Rachel Vacher
- University of Orleans and CNRS, UMR6218, Orleans, France
| | | | - Alain Fautrel
- INSERM U991, Université de Rennes 1, Rennes, France
- H2P2 Histopathological platform IFR140 INSERM U991, Université de Rennes 1, Rennes, France
| | | | - Lizette Fick
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - Sabine Charron
- University of Orleans and CNRS, UMR6218, Orleans, France
| | | | - Gérard Eberl
- Institute Pasteur, Laboratory of Lymphoid Tissue Development, CNRS URA 1961, Paris, France
| | - Marc Le Bert
- University of Orleans and CNRS, UMR6218, Orleans, France
| | | | | | | | - Bernhard Ryffel
- University of Orleans and CNRS, UMR6218, Orleans, France
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - Isabelle Couillin
- University of Orleans and CNRS, UMR6218, Orleans, France
- Key-Obs S. A S., Orleans, France
- * E-mail:
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25
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Besnard AG, Sabat R, Dumoutier L, Renauld JC, Willart M, Lambrecht B, Teixeira MM, Charron S, Fick L, Erard F, Warszawska K, Wolk K, Quesniaux V, Ryffel B, Togbe D. Dual Role of IL-22 in allergic airway inflammation and its cross-talk with IL-17A. Am J Respir Crit Care Med 2011; 183:1153-63. [PMID: 21297073 DOI: 10.1164/rccm.201008-1383oc] [Citation(s) in RCA: 161] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
RATIONALE IL-22 has both proinflammatory and antiinflammatory properties. Its role in allergic lung inflammation has not been explored. OBJECTIVES To investigate the expression and roles of IL-22 in the onset and resolution of experimental allergic asthma and its cross-talk with IL-17A. METHODS IL-22 expression was assessed in patient samples and in the lung of mice immunized and challenged with ovalbumin. IL-22 functions in allergic airway inflammation were evaluated using mice deficient in IL-22 or anti-IL-22 neutralizing antibodies. Moreover, the effects of recombinant IL-22 and IL-17A neutralizing antibodies were investigated. MEASUREMENTS AND MAIN RESULTS Increased pulmonary IL-22 expression is found in the serum of patients with asthma and mice immunized and challenged with ovalbumin. Allergic lung inflammation is IL-22 dependent because eosinophil recruitment, Th2 cytokine including IL-13 and IL-33, chemokine production, airway hyperreactivity, and mucus production are drastically reduced in mice deficient in IL-22 or by IL-22 antibody neutralization during immunization of wild-type mice. By contrast, IL-22 neutralization during antigen challenge enhanced allergic lung inflammation with increased Th2 cytokines. Consistent with this, recombinant IL-22 given with allergen challenge protects mice from lung inflammation. Finally, IL-22 may regulate the expression and proinflammatory properties of IL-17A in allergic lung inflammation. CONCLUSIONS IL-22 is required for the onset of allergic asthma, but functions as a negative regulator of established allergic inflammation. Our study reveals that IL-22 contributes to the proinflammatory properties of IL-17A in experimental allergic asthma.
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Affiliation(s)
- Anne-Gaelle Besnard
- Université de Orléans and CNRS-UMR6218, Molecular Immunology and Embryology, 3B Rue de la Férollerie, 45071 Orléans Cedex 2, France
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Fauconnier M, Bourigault ML, Meme S, Szeremeta F, Palomo J, Danneels A, Charron S, Fick L, Jacobs M, Beloeil JC, Ryffel B, Quesniaux VFJ. Protein kinase C-theta is required for development of experimental cerebral malaria. Am J Pathol 2010; 178:212-21. [PMID: 21224058 DOI: 10.1016/j.ajpath.2010.11.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2010] [Revised: 09/08/2010] [Accepted: 09/14/2010] [Indexed: 11/18/2022]
Abstract
Cerebral malaria is the most severe neurologic complication in children and young adults infected with Plasmodium falciparum. T-cell activation is required for development of Plasmodium berghei ANKA (PbA)-induced experimental cerebral malaria (CM). To characterize the T-cell activation pathway involved, the role of protein kinase C-theta (PKC-θ) in experimental CM development was examined. PKC-θ-deficient mice are resistant to CM development. In the absence of PKC-θ, no neurologic sign of CM developed after blood stage PbA infection. Resistance of PKC-θ-deficient mice correlated with unaltered cerebral microcirculation and absence of ischemia, as documented by magnetic resonance imaging and magnetic resonance angiography, whereas wild-type mice developed distinct microvascular pathology. Recruitment and activation of CD8(+) T cells, and ICAM-1 and CD69 expression were reduced in the brain of resistant mice; however, the pulmonary inflammation and edema associated with PbA infection were still present in the absence of functional PKC-θ. Resistant PKC-θ-deficient mice developed high parasitemia, and died at 3 weeks with severe anemia. Therefore, PKC-θ signaling is crucial for recruitment of CD8(+) T cells and development of brain microvascular pathology resulting in fatal experimental CM, and may represent a novel therapeutic target of CM.
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Affiliation(s)
- Mathilde Fauconnier
- University of Orléans and CNRS, Molecular Immunology and Embryology UMR6218, Orléans, France
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Guiton R, Vasseur V, Charron S, Arias M, Van Langendonck N, Buzoni‐Gatel D, Ryffel B, Dimier‐Poisson I. Interleukin 17 Receptor Signaling Is Deleterious duringToxoplasma gondiiInfection in Susceptible BL6 Mice. J Infect Dis 2010; 202:427-35. [DOI: 10.1086/653738] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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Couillin I, Vasseur V, Charron S, Gasse P, Tavernier M, Guillet J, Lagente V, Fick L, Jacobs M, Coelho FR, Moser R, Ryffel B. IL-1R1/MyD88 signaling is critical for elastase-induced lung inflammation and emphysema. J Immunol 2010; 183:8195-202. [PMID: 20007584 DOI: 10.4049/jimmunol.0803154] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Lung emphysema and fibrosis are severe complications of chronic obstructive pulmonary disease, and uncontrolled protease activation may be involved in the pathogenesis. Using experimental elastase-induced acute inflammation, we demonstrate here that inflammation and development of emphysema is IL-1R1 and Toll/IL-1R signal transduction adaptor MyD88 dependent; however, TLR recognition is dispensable in this model. Elastase induces IL-1beta, TNF-alpha, keratinocyte-derived chemokine, and IL-6 secretion and neutrophil recruitment in the lung, which is drastically reduced in the absence of IL-1R1 or MyD88. Further, tissue destruction with emphysema and fibrosis is attenuated in the lungs of IL-1R1- and MyD88-deficient mice. Specific blockade of IL-1 by IL-1R antagonist diminishes acute inflammation and emphysema. Finally, IL-1beta production and inflammation are reduced in mice deficient for the NALP3 inflammasome component apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), and we identified uric acid, which is produced upon elastase-induced lung injury, as an activator of the NALP3/ASC inflammasome. In conclusion, elastase-mediated lung pathology depends on inflammasome activation with IL-1beta production. IL-1beta therefore represents a critical mediator and a possible therapeutic target of lung inflammation leading to emphysema.
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Affiliation(s)
- Isabelle Couillin
- Laboratory of Molecular Immunology and Embryology, University of Orleans and Centre National de la Recherche Scientifique, Orleans, France.
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Charron S, Koechlin E. Motivational incentives underlying human intentions in the prefrontal cortex. Neuroimage 2009. [DOI: 10.1016/s1053-8119(09)71968-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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31
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Doz E, Rose S, Court N, Front S, Vasseur V, Charron S, Gilleron M, Puzo G, Fremaux I, Delneste Y, Erard F, Ryffel B, Martin OR, Quesniaux VFJ. Mycobacterial phosphatidylinositol mannosides negatively regulate host Toll-like receptor 4, MyD88-dependent proinflammatory cytokines, and TRIF-dependent co-stimulatory molecule expression. J Biol Chem 2009; 284:23187-96. [PMID: 19561082 DOI: 10.1074/jbc.m109.037846] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mycobacterium tuberculosis modulates host immune responses through proteins and complex glycolipids. Here, we report that the glycosylphosphatidylinositol anchor phosphatidyl-myo-inositol hexamannosides PIM(6) or PIM(2) exert potent anti-inflammatory activities. PIM strongly inhibited the Toll-like receptor (TLR4) and myeloid differentiation protein 88 (MyD88)-mediated release of NO, cytokines, and chemokines, including tumor necrosis factor (TNF), interleukin 12 (IL-12) p40, IL-6, keratinocyte-derived chemokine, and also IL-10 by lipopolysaccharide (LPS)-activated macrophages. This effect was independent of the presence of TLR2. PIM also reduced the LPS-induced MyD88-independent, TIR domain-containing adaptor protein inducing interferon beta (TRIF)-mediated expression of co-stimulatory receptors. PIM inhibited LPS/TLR4-induced NFkappaB translocation. Synthetic PIM(1) and a PIM(2) mimetic recapitulated these in vitro activities and inhibited endotoxin-induced airway inflammation, TNF and keratinocyte-derived chemokine secretion, and neutrophil recruitment in vivo. Mannosyl, two acyl chains, and phosphatidyl residues are essential for PIM anti-inflammatory activity, whereas the inosityl moiety is dispensable. Therefore, PIM exert potent antiinflammatory effects both in vitro and in vivo that may contribute to the strategy developed by mycobacteria for repressing the host innate immunity, and synthetic PIM analogs represent powerful anti-inflammatory leads.
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Affiliation(s)
- Emilie Doz
- Orleans University and CNRS, Molecular Immunology and Embryology, UMR6218, France
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Gasse P, Riteau N, Charron S, Girre S, Fick L, Pétrilli V, Tschopp J, Lagente V, Quesniaux VFJ, Ryffel B, Couillin I. Uric Acid Is a Danger Signal Activating NALP3 Inflammasome in Lung Injury Inflammation and Fibrosis. Am J Respir Crit Care Med 2009; 179:903-13. [DOI: 10.1164/rccm.200808-1274oc] [Citation(s) in RCA: 320] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Gasse P, Mary C, Guenon I, Noulin N, Charron S, Schnyder-Candrian S, Schnyder B, Akira S, Quesniaux VFJ, Lagente V, Ryffel B, Couillin I. IL-1R1/MyD88 signaling and the inflammasome are essential in pulmonary inflammation and fibrosis in mice. J Clin Invest 2008; 117:3786-99. [PMID: 17992263 DOI: 10.1172/jci32285] [Citation(s) in RCA: 245] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2007] [Accepted: 09/12/2007] [Indexed: 01/17/2023] Open
Abstract
The molecular mechanisms of acute lung injury resulting in inflammation and fibrosis are not well established. Here we investigate the roles of the IL-1 receptor 1 (IL-1R1) and the common adaptor for Toll/IL-1R signal transduction, MyD88, in this process using a murine model of acute pulmonary injury. Bleomycin insult results in expression of neutrophil and lymphocyte chemotactic factors, chronic inflammation, remodeling, and fibrosis. We demonstrate that these end points were attenuated in the lungs of IL-1R1- and MyD88-deficient mice. Further, in bone marrow chimera experiments, bleomycin-induced inflammation required primarily MyD88 signaling from radioresistant resident cells. Exogenous rIL-1beta recapitulated a high degree of bleomycin-induced lung pathology, and specific blockade of IL-1R1 by IL-1 receptor antagonist dramatically reduced bleomycin-induced inflammation. Finally, we found that lung IL-1beta production and inflammation in response to bleomycin required ASC, an inflammasome adaptor molecule. In conclusion, bleomycin-induced lung pathology required the inflammasome and IL-1R1/MyD88 signaling, and IL-1 represented a critical effector of pathology and therapeutic target of chronic lung inflammation and fibrosis.
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Affiliation(s)
- Pamela Gasse
- Laboratory of Molecular Immunology and Embryology, University of Orleans and CNRS, Orleans, France
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Togbe D, Schofield L, Grau GE, Schnyder B, Boissay V, Charron S, Rose S, Beutler B, Quesniaux VFJ, Ryffel B. Murine cerebral malaria development is independent of toll-like receptor signaling. Am J Pathol 2007; 170:1640-8. [PMID: 17456769 PMCID: PMC1854958 DOI: 10.2353/ajpath.2007.060889] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 01/26/2007] [Indexed: 11/20/2022]
Abstract
Malaria pigment hemozoin was reported to activate the innate immunity by Toll-like receptor (TLR)-9 engagement. However, the role of TLR activation for the development of cerebral malaria (CM), a lethal complication of malaria infection in humans, is unknown. Using Plasmodium berghei ANKA (PbA) infection in mice as a model of CM, we report here that TLR9-deficient mice are not protected from CM. To exclude the role of other members of the TLR family in PbA recognition, we infected mice deficient for single TLR1, -2, -3, -4, -6, -7, or -9 and their adapter proteins MyD88, TIRAP, and TRIF. In contrast to lymphotoxin alpha-deficient mice, which are resistant to CM, all TLR-deficient mice were as sensitive to fatal CM development as wild-type control mice and developed typical microvascular damage with vascular leak and hemorrhage in the brain and lung, together with comparable parasitemia, thrombocytopenia, neutrophilia, and lymphopenia. In conclusion, the present data do not exclude the possibility that malarial molecular motifs may activate the innate immune system. However, TLR-dependent activation of innate immunity is unlikely to contribute significantly to the proinflammatory response to PbA infection and the development of fatal CM.
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Affiliation(s)
- Dieudonnée Togbe
- Molecular Immunology and Embryology, Centre National de la Recherche Scientifique, and University of Orleans, Transgenose Institute, Orleans, France
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Duong C, Charron S, Deng Y, Xiao C, Ménard A, Roy J, Deng AY. Individual QTLs controlling quantitative variation in blood pressure inherited in a Mendelian mode. Heredity (Edinb) 2006; 98:165-71. [PMID: 17119551 DOI: 10.1038/sj.hdy.6800920] [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] [Indexed: 11/08/2022] Open
Abstract
We studied three possible genotypes at 10 well-defined blood pressure (BP) QTLs using congenic rat lines. The central question was whether the hypertensive or normotensive allele is dominant, or whether there is partial dominance. The congenic strains were employed to investigate the BP effects of alleles originating from normotensive rats in the background of hypertensive Dahl salt-sensitive (DSS) rats. The normotensive alleles at eight QTLs were fully dominant over DSS alleles, which we tentatively interpreted as indicating that DSS rats incurred a loss of function at these loci and that the QTLs produced BP-reducing agents. In contrast, the normotensive allele of only one QTL was recessive over its DSS counterpart, implying a gain of function at this QTL or a null allele involved in generating a BP-elevating agent. Only one locus, C17QTL, had alleles exhibiting partial dominance. These estimates of dominance differ considerably from those obtained by QTL analysis in a F2 cross. This disagreement demonstrates the importance of establishing a cause-effect relationship between a QTL and its phenotypic effect via congenic strains. The dominance relationships suggest pertinent strategies for gene identification and pharmaceutical intervention.
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Affiliation(s)
- C Duong
- Department of Medicine, Research Centre, Centre hospitalier de l'Université de Montréal (CHUM)-Technopôle Angus, 2901 Rachel Street East, Montréal, Québec, Canada
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Abstract
Two experiments studied the frequency pattern of TLS (temporary loudness shift) as a function of the level and frequency of the fatiguing sound. In experiment 1, the fatiguing tones were intermittent 375-, 1500-, or 3000-Hz tones (10 s on/10 s off) at 75, 80, 85, 90, or 95 dB SPL. The TLS patterns were established for a continuous, 60-phon test tone at different frequencies presented simultaneously with the intermittent fatiguing tone. In experiment 2, a 1000-Hz exposure tone with an intermittency of 10 s on/20 s off was used with a continuous 60-dB test tone at different frequencies. In both experiments, the total exposure duration was 60 s; TLS was measured 5 s after the exposure ended. For the lowest two exposure levels, the TLS pattern had one peak centered on the exposure frequency. As the exposure level increased, a two-peak pattern became evident, with the second peak at higher test frequencies. This finding could be interpreted as psychoacoustical evidence for the double (passive and active) mode of displacement of the basilar membrane. In experiment 2, a TTS (temporary threshold shift) measurement after exposure to a 45-min, 1000-Hz tone at 90 dB was added to the TLS sessions. The correlations between maximum TTS after a 45-min exposure and the TLS obtained after a 60-s exposure were calculated for each of the exposure levels and test frequencies used in TLS measurements. The correlation reached as high as 0.9 for TLSs measured at 1120 Hz after a 90-dB exposure; it was smaller but significant for TLSs at the exposure frequency. Despite these correlations, differences in the overall patterns of TTS and TLS suggest that they stem from two different mechanisms.
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Affiliation(s)
- M C Botte
- Laboratory of Experimental Psychology (CNRS U.R.A. 316), Paris, France
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Excler JL, Charron S, Faila-Bahati C. [Breast feeding and birth spacing in Burundi: an approach]. Med Trop (Mars) 1988; 48:117-22. [PMID: 3405071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Breast-feeding (BFD), post-partum amenorrhea (PPA), and birth interval (BI) were studied in 247 mothers from Burundi (159 rural and 88 urban). BFD was higher in rural than in urban areas (23.8 +/- 6.8 vs 16.5 +/- 7.2 mths, p less than 0.001), as for PPA (16.9 +/- 8.5 vs 8.9 +/- 8 mths, p less than 0.001) and Bl (29 +/- 11 vs 25.7 +/- 10.7 mths, p less than 0.01). PPA of non exclusively breast-feeding (NEB) mothers was lower than that of the other mothers (5.7 +/- 6.5 vs 13.9 +/- 9 mths, p less than 0.001). The proportion of mothers with PPA less than or equal to 12 months was higher in NEB mothers (88.9% vs 49%, p less than 0.001). The relative risk of pregnancy 9 to 12 mths after a birth was 4 times higher for these mothers (28% vs 9%, RR = 3.9, p less than 0.001). PPA and BI were correlated with BFD (respectively r = 0.644 and r = 0.21, p less than 0.001). A multivariate analysis showed that PPA is lowered when BFD and frequency of sucking are reduced in urban high socio-economic levels (R = 56%, p less than 0.01). BI was not so lowered in urban area than expected with a lower BFD and PPA. These data suggest that post-partum infertility period lowered in urban area would be partially counterbalanced by cultural taboo inhibiting sexual intercourse during breast-feeding. Deep modification in sexual behavior accelerated by use of contraceptives should lead to be careful in their spread in family planning programmes where breast-feeding promotion is more than ever a priority.
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Affiliation(s)
- J L Excler
- Clinique en Pédiatrie, épidémiologiste, Centre hospitalier universitaire de Kamenge, Burundi
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