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Jasmin NH, Thin MZ, Johnson RD, Jackson LH, Roberts TA, David AL, Lythgoe MF, Yang PC, Davidson SM, Camelliti P, Stuckey DJ. Myocardial Viability Imaging using Manganese-Enhanced MRI in the First Hours after Myocardial Infarction. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:e2003987. [PMID: 34105284 PMCID: PMC8188227 DOI: 10.1002/advs.202003987] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Revised: 02/08/2021] [Indexed: 05/19/2023]
Abstract
Early measurements of tissue viability after myocardial infarction (MI) are essential for accurate diagnosis and treatment planning but are challenging to obtain. Here, manganese, a calcium analogue and clinically approved magnetic resonance imaging (MRI) contrast agent, is used as an imaging biomarker of myocardial viability in the first hours after experimental MI. Safe Mn2+ dosing is confirmed by measuring in vitro beating rates, calcium transients, and action potentials in cardiomyocytes, and in vivo heart rates and cardiac contractility in mice. Quantitative T1 mapping-manganese-enhanced MRI (MEMRI) reveals elevated and increasing Mn2+ uptake in viable myocardium remote from the infarct, suggesting MEMRI offers a quantitative biomarker of cardiac inotropy. MEMRI evaluation of infarct size at 1 h, 1 and 14 days after MI quantifies myocardial viability earlier than the current gold-standard technique, late-gadolinium-enhanced MRI. These data, coupled with the re-emergence of clinical Mn2+ -based contrast agents open the possibility of using MEMRI for direct evaluation of myocardial viability early after ischemic onset in patients.
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Affiliation(s)
- Nur Hayati Jasmin
- UCL Centre for Advanced Biomedical ImagingDivision of MedicineUniversity College LondonLondonWC1E 6DDUK
- School of Medical ImagingFaculty of Health SciencesUniversiti Sultan Zainal AbidinKuala Terengganu21300Malaysia
| | - May Zaw Thin
- UCL Centre for Advanced Biomedical ImagingDivision of MedicineUniversity College LondonLondonWC1E 6DDUK
| | - Robert D. Johnson
- School of Biosciences and MedicineUniversity of SurreyGuildfordGU2 7XHUK
| | - Laurence H. Jackson
- School of Biomedical Engineering & Imaging SciencesKing's College LondonLondonSE1 7EHUK
| | - Thomas A. Roberts
- School of Biomedical Engineering & Imaging SciencesKing's College LondonLondonSE1 7EHUK
| | - Anna L. David
- UCL Elizabeth Garrett Anderson Institute for Women's HealthLondonWC1E 6BTUK
| | - Mark F. Lythgoe
- UCL Centre for Advanced Biomedical ImagingDivision of MedicineUniversity College LondonLondonWC1E 6DDUK
| | - Philip C. Yang
- Division of Cardiovascular MedicineDepartment of MedicineStanford UniversityStanfordCA94305USA
| | - Sean M. Davidson
- The Hatter Cardiovascular InstituteUniversity College London67 Chenies MewsLondonWC1E 6HXUK
| | - Patrizia Camelliti
- School of Biosciences and MedicineUniversity of SurreyGuildfordGU2 7XHUK
| | - Daniel J. Stuckey
- UCL Centre for Advanced Biomedical ImagingDivision of MedicineUniversity College LondonLondonWC1E 6DDUK
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Fontaine SN, Ingram A, Cloyd RA, Meier SE, Miller E, Lyons D, Nation GK, Mechas E, Weiss B, Lanzillotta C, Di Domenico F, Schmitt F, Powell DK, Vandsburger M, Abisambra JF. Identification of changes in neuronal function as a consequence of aging and tauopathic neurodegeneration using a novel and sensitive magnetic resonance imaging approach. Neurobiol Aging 2017; 56:78-86. [PMID: 28500878 DOI: 10.1016/j.neurobiolaging.2017.04.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Revised: 03/09/2017] [Accepted: 04/09/2017] [Indexed: 12/20/2022]
Abstract
Tauopathies, the most common of which is Alzheimer's disease (AD), constitute the most crippling neurodegenerative threat to our aging population. Tauopathic patients have significant cognitive decline accompanied by irreversible and severe brain atrophy, and it is thought that neuronal dysfunction begins years before diagnosis. Our current understanding of tauopathies has yielded promising therapeutic interventions but have all failed in clinical trials. This is partly due to the inability to identify and intervene in an effective therapeutic window early in the disease process. A major challenge that contributes to the definition of an early therapeutic window is limited technologies. To address these challenges, we modified and adapted a manganese-enhanced magnetic resonance imaging (MEMRI) approach to provide sensitive and quantitative power to detect changes in broad neuronal function in aging mice. Considering that tau tangle burden correlates well with cognitive impairment in Alzheimer's patients, we performed our MEMRI approach in a time course of aging mice and an accelerated mouse model of tauopathy. We measured significant changes in broad neuronal function as a consequence of age, and in transgenic mice, before the deposition of bona fide tangles. This MEMRI approach represents the first diagnostic measure of neuronal dysfunction in mice. Successful translation of this technology in the clinic could serve as a sensitive diagnostic tool for the definition of effective therapeutic windows.
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Affiliation(s)
- Sarah N Fontaine
- Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA; Epilepsy Center, University of Kentucky, Lexington, KY, USA
| | - Alexandria Ingram
- Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA
| | - Ryan A Cloyd
- Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA
| | - Shelby E Meier
- Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA; Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - Emily Miller
- Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA
| | - Danielle Lyons
- Spinal Cord Injury and Brain Injury Research Center, University of Kentucky, Lexington, KY, USA
| | - Grant K Nation
- Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA
| | - Elizabeth Mechas
- Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA
| | - Blaine Weiss
- Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA
| | - Chiara Lanzillotta
- Department of Biochemical Sciences, Sapienza University of Rome, Rome, Italy
| | - Fabio Di Domenico
- Department of Biochemical Sciences, Sapienza University of Rome, Rome, Italy
| | - Frederick Schmitt
- Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA
| | - David K Powell
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY, USA
| | - Moriel Vandsburger
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, USA; Department of Biomedical Engineering, University of Kentucky, Lexington, KY, USA
| | - Jose F Abisambra
- Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA; Epilepsy Center, University of Kentucky, Lexington, KY, USA; Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, USA; Spinal Cord Injury and Brain Injury Research Center, University of Kentucky, Lexington, KY, USA.
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Bakermans AJ, Abdurrachim D, Moonen RPM, Motaal AG, Prompers JJ, Strijkers GJ, Vandoorne K, Nicolay K. Small animal cardiovascular MR imaging and spectroscopy. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2015; 88-89:1-47. [PMID: 26282195 DOI: 10.1016/j.pnmrs.2015.03.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 03/09/2015] [Accepted: 03/09/2015] [Indexed: 06/04/2023]
Abstract
The use of MR imaging and spectroscopy for studying cardiovascular disease processes in small animals has increased tremendously over the past decade. This is the result of the remarkable advances in MR technologies and the increased availability of genetically modified mice. MR techniques provide a window on the entire timeline of cardiovascular disease development, ranging from subtle early changes in myocardial metabolism that often mark disease onset to severe myocardial dysfunction associated with end-stage heart failure. MR imaging and spectroscopy techniques play an important role in basic cardiovascular research and in cardiovascular disease diagnosis and therapy follow-up. This is due to the broad range of functional, structural and metabolic parameters that can be quantified by MR under in vivo conditions non-invasively. This review describes the spectrum of MR techniques that are employed in small animal cardiovascular disease research and how the technological challenges resulting from the small dimensions of heart and blood vessels as well as high heart and respiratory rates, particularly in mice, are tackled.
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Affiliation(s)
- Adrianus J Bakermans
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands; Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Desiree Abdurrachim
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Rik P M Moonen
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Abdallah G Motaal
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands; Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Jeanine J Prompers
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Gustav J Strijkers
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands; Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Katrien Vandoorne
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Klaas Nicolay
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands.
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Farkas V, Szentandrássy N, Bárándi L, Hegyi B, Ruzsnavszky F, Ruzsnavszky O, Horváth B, Bányász T, Magyar J, Márton I, Nánási PP. Interaction between Ca(2+) channel blockers and isoproterenol on L-type Ca(2+) current in canine ventricular cardiomyocytes. Acta Physiol (Oxf) 2012; 206:42-50. [PMID: 22520840 DOI: 10.1111/j.1748-1716.2012.02448.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Revised: 01/31/2012] [Accepted: 04/17/2012] [Indexed: 11/28/2022]
Abstract
AIM The aim of this work was to study antagonistic interactions between the effects of various types of Ca(2+) channel blockers and isoproterenol on the amplitude of L-type Ca(2+) current in canine ventricular cells. METHODS Whole-cell version of the patch clamp technique was used to study the effect of isoproterenol on Ca(2+) current in the absence and presence of Ca(2+) channel-blocking agents, including nifedipine, nisoldipine, diltiazem, verapamil, CoCl(2) and MnCl(2) . RESULTS Five micromolar Nifedipine, 1 μM nisoldipine, 10 μM diltiazem, 5 μM verapamil, 3 mM CoCl(2) and 5 mM MnCl(2) evoked uniformly a 90-95% blockade of Ca(2+) current in the absence of isoproterenol. Isoproterenol (100 nM) alone increased the amplitude of Ca(2+) current from 6.8 ± 1.3 to 23.7 ± 2.2 pA/pF in a reversible manner. Isoproterenol caused a marked enhancement of Ca(2+) current even in the presence of nifedipine, nisoldipine, diltiazem and verapamil, but not in the presence of CoCl(2) or MnCl(2) . CONCLUSION The results indicate that the action of isoproterenol is different in the presence of organic and inorganic Ca(2+) channel blockers. CoCl(2) and MnCl(2) were able to fully prevent the effect of isoproterenol on Ca(2+) current, while the organic Ca(2+) channel blockers failed to do so. This has to be born in mind when the effects of organic Ca(2+) channel blockers are evaluated either experimentally or clinically under conditions of increased sympathetic tone.
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Affiliation(s)
- V. Farkas
- Department of Dentistry; University of Debrecen; Debrecen; Hungary
| | - N. Szentandrássy
- Department of Physiology; University of Debrecen; Debrecen; Hungary
| | - L. Bárándi
- Department of Physiology; University of Debrecen; Debrecen; Hungary
| | - B. Hegyi
- Department of Physiology; University of Debrecen; Debrecen; Hungary
| | - F. Ruzsnavszky
- Department of Physiology; University of Debrecen; Debrecen; Hungary
| | - O. Ruzsnavszky
- Department of Physiology; University of Debrecen; Debrecen; Hungary
| | - B. Horváth
- Department of Physiology; University of Debrecen; Debrecen; Hungary
| | - T. Bányász
- Department of Physiology; University of Debrecen; Debrecen; Hungary
| | - J. Magyar
- Department of Physiology; University of Debrecen; Debrecen; Hungary
| | - I. Márton
- Department of Dentistry; University of Debrecen; Debrecen; Hungary
| | - P. P. Nánási
- Department of Physiology; University of Debrecen; Debrecen; Hungary
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Vandsburger MH, French BA, Kramer CM, Zhong X, Epstein FH. Displacement-encoded and manganese-enhanced cardiac MRI reveal that nNOS, not eNOS, plays a dominant role in modulating contraction and calcium influx in the mammalian heart. Am J Physiol Heart Circ Physiol 2011; 302:H412-9. [PMID: 22058155 DOI: 10.1152/ajpheart.00705.2011] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Within cardiomyocytes, endothelial nitric oxide synthase (eNOS) and neuronal nitric oxide synthase (nNOS) are thought to modulate L-type calcium channel (LTCC) function and sarcoplasmic reticulum calcium cycling, respectively. However, divergent results from mostly invasive prior studies suggest more complex roles. To elucidate the roles of nNOS and eNOS in vivo, we applied noninvasive cardiac MRI to study wild-type (WT), eNOS(-/-), and nNOS(-/-) mice. An in vivo index of LTCC flux (LTCCI) was measured at baseline (Bsl), dobutamine (Dob), and dobutamine + carbacholamine (Dob + CCh) using manganese-enhanced MRI. Displacement-encoded MRI assessed contractile function by measuring circumferential strain (E(cc)) and systolic (dE(cc)/dt) and diastolic (dE(cc)/dt(diastolic)) strain rates at Bsl, Dob, and Dob + CCh. Bsl LTCCI was highest in nNOS(-/-) mice (P < 0.05 vs. WT and eNOS(-/-)) and increased only in WT and eNOS(-/-) mice with Dob (P < 0.05 vs. Bsl). LTCCI decreased significantly from Dob levels with Dob + CCh in all mice. Contractile function, as assessed by E(cc), was similar in all mice at Bsl. With Dob, E(cc) increased significantly in WT and eNOS(-/-) but not nNOS(-/-) mice (P < 0.05 vs. WT and eNOS(-/-)). With Dob + CCh, E(cc) returned to baseline levels in all mice. Systolic blood pressure, measured via tail plethysmography, was highest in eNOS(-/-) mice (P < 0.05 vs. WT and nNOS(-/-)). Mice deficient in nNOS demonstrate increased Bsl LTCC function and an attenuated contractile reserve to Dob, whereas eNOS(-/-) mice demonstrate normal LTCC and contractile function under all conditions. These results suggest that nNOS, not eNOS, plays the dominant role in modulating Ca(2+) cycling in the heart.
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Affiliation(s)
- Moriel H Vandsburger
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA 22908, USA
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Vandsburger MH, Epstein FH. Emerging MRI methods in translational cardiovascular research. J Cardiovasc Transl Res 2011; 4:477-92. [PMID: 21452060 DOI: 10.1007/s12265-011-9275-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2011] [Accepted: 03/15/2011] [Indexed: 12/11/2022]
Abstract
Cardiac magnetic resonance imaging (CMR) has become a reference standard modality for imaging of left ventricular (LV) structure and function and, using late gadolinium enhancement, for imaging myocardial infarction. Emerging CMR techniques enable a more comprehensive examination of the heart, making CMR an excellent tool for use in translational cardiovascular research. Specifically, emerging CMR methods have been developed to measure the extent of myocardial edema, changes in ventricular mechanics, changes in tissue composition as a result of fibrosis, and changes in myocardial perfusion as a function of both disease and infarct healing. New CMR techniques also enable the tracking of labeled cells, molecular imaging of biomarkers of disease, and changes in calcium flux in cardiomyocytes. In addition, MRI can quantify blood flow velocity and wall shear stress in large blood vessels. Almost all of these techniques can be applied in both pre-clinical and clinical settings, enabling both the techniques themselves and the knowledge gained using such techniques in pre-clinical research to be translated from the lab bench to the patient bedside.
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Affiliation(s)
- Moriel H Vandsburger
- Department of Biological Regulation, Weizmann Institute of Science, 76100, Rehovot, Israel.
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Takemoto J, Masumiya H, Nunoki K, Sato T, Nakagawa H, Ikeda Y, Arai Y, Yanagisawa T. Potentiation of potassium currents by beta-adrenoceptor agonists in human urinary bladder smooth muscle cells: a possible electrical mechanism of relaxation. Pharmacology 2008; 81:251-8. [PMID: 18253064 DOI: 10.1159/000114719] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2007] [Accepted: 10/10/2007] [Indexed: 11/19/2022]
Abstract
We examined the effects of beta-adrenoceptor agonists on the membrane currents of smooth muscle cells from the human urinary bladder using a whole-cell patch clamp to investigate the involvement of Ca(2+)-activated K(+) (K(Ca)) channels in relaxation by beta-adrenergic agonists. With 0.05 mmol/l EGTA in the patch pipette, depolarizing pulses evoked outward rectifying currents. Isoproterenol (1 micromol/l) significantly increased the membrane currents by 75% at +80 mV with 0.05 mmol/l EGTA pipette solution. BRL 37344 (1 micromol/l) significantly increased the membrane currents by 44% at +80 mV. Iberiotoxin (100 nmol/l) significantly decreased the membrane currents by 60% at +80 mV. In the presence of iberiotoxin, the potentiation of the outward currents by isoproterenol was greatly suppressed and, in the presence of iberiotoxin and apamin (1 micromol/l), the potentiation by isoproterenol was totally abolished. On the other hand, with 5 mmol/l EGTA pipette solution, depolarizing pulses evoked smaller outward currents. Isoproterenol (1 micromol/l) did not change the membrane currents with 5 mmol/l EGTA pipette solution. The real-time PCR analysis revealed the expression of beta(2)-adrenoceptors in the cells. These results suggest that Ca(2+)-activated and iberiotoxin- and apamin-sensitive currents via both large-conductance and small-conductance K(Ca) channels could be increased by stimulation of beta(2)-adrenoceptors.
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Affiliation(s)
- Jun Takemoto
- Department of Molecular Pharmacology, Graduate School of Medicine, Tohoku University, Sendai, Japan
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Maack C, O'Rourke B. Excitation-contraction coupling and mitochondrial energetics. Basic Res Cardiol 2007; 102:369-92. [PMID: 17657400 PMCID: PMC2785083 DOI: 10.1007/s00395-007-0666-z] [Citation(s) in RCA: 186] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2007] [Revised: 06/12/2007] [Accepted: 06/13/2007] [Indexed: 12/20/2022]
Abstract
Cardiac excitation-contraction (EC) coupling consumes vast amounts of cellular energy, most of which is produced in mitochondria by oxidative phosphorylation. In order to adapt the constantly varying workload of the heart to energy supply, tight coupling mechanisms are essential to maintain cellular pools of ATP, phosphocreatine and NADH. To our current knowledge, the most important regulators of oxidative phosphorylation are ADP, Pi, and Ca2+. However, the kinetics of mitochondrial Ca2+-uptake during EC coupling are currently a matter of intense debate. Recent experimental findings suggest the existence of a mitochondrial Ca2+ microdomain in cardiac myocytes, justified by the close proximity of mitochondria to the sites of cellular Ca2+ release, i. e., the ryanodine receptors of the sarcoplasmic reticulum. Such a Ca2+ microdomain could explain seemingly controversial results on mitochondrial Ca2+ uptake kinetics in isolated mitochondria versus whole cardiac myocytes. Another important consideration is that rapid mitochondrial Ca2+ uptake facilitated by microdomains may shape cytosolic Ca2+ signals in cardiac myocytes and have an impact on energy supply and demand matching. Defects in EC coupling in chronic heart failure may adversely affect mitochondrial Ca2+ uptake and energetics, initiating a vicious cycle of contractile dysfunction and energy depletion. Future therapeutic approaches in the treatment of heart failure could be aimed at interrupting this vicious cycle.
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Affiliation(s)
- Christoph Maack
- Klinik für Innere Medizin III, Universitätsklinikum des Saarlandes, 66421, Homburg/Saar, Germany.
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Heilig EA, Thompson KJ, Molina RM, Ivanov AR, Brain JD, Wessling-Resnick M. Manganese and iron transport across pulmonary epithelium. Am J Physiol Lung Cell Mol Physiol 2006; 290:L1247-59. [PMID: 16428268 DOI: 10.1152/ajplung.00450.2005] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Pathways mediating pulmonary metal uptake remain unknown. Because absorption of iron and manganese could involve similar mechanisms, transferrin (Tf) and transferrin receptor (TfR) expression in rat lungs was examined. Tf mRNA was detected in bronchial epithelium, type II alveolar cells, macrophages, and bronchus-associated lymphoid tissue (BALT). Tf protein levels in lung and bronchoalveolar lavage fluid did not change in iron deficiency despite increased plasma levels, suggesting that lung Tf concentrations are regulated by local synthesis in a manner independent of body iron status. Iron oxide exposure upregulated Tf mRNA in bronchial and alveolar epithelium, macrophages, and BALT, but protein was not significantly increased. In contrast, TfR mRNA and protein were both upregulated by iron deficiency. To examine potential interactions with lung Tf, rats were intratracheally instilled with (54)Mn or (59)Fe. Unlike (59)Fe, interactions between (54)Mn and Tf in lung fluid were not detected. Absorption of intratracheally instilled (54)Mn from the lungs to the blood was unimpaired in Belgrade rats homozygous for the functionally defective G185R allele of divalent metal transporter-1, indicating that this transporter is also not involved in pulmonary manganese absorption. Pharmacological studies of (54)Mn uptake by A549 cells suggest that metal uptake by type II alveolar epithelial cells is associated with activities of both L-type Ca(2+) channels and TRPM7, a member of the transient receptor potential melastatin subfamily. These results demonstrate that iron and manganese are absorbed by the pulmonary epithelium through different pathways and reveal the potential role for nonselective calcium channels in lung metal clearance.
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Affiliation(s)
- Elizabeth A Heilig
- Deptartment of Genetics and Complex Diseases, Harvard School of Public Health, 665 Huntington Avenue, Boston, MA 02115, USA
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