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Wachsmuth L, Hebbelmann L, Prade J, Kohnert LC, Lambers H, Lüttjohann A, Budde T, Hess A, Faber C. Epilepsy-related functional brain network alterations are already present at an early age in the GAERS rat model of genetic absence epilepsy. Front Neurol 2024; 15:1355862. [PMID: 38529038 PMCID: PMC10961455 DOI: 10.3389/fneur.2024.1355862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Accepted: 02/16/2024] [Indexed: 03/27/2024] Open
Abstract
Introduction Genetic Absence Epilepsy Rats from Strasbourg (GAERS) represent a model of genetic generalized epilepsy. The present longitudinal study in GAERS and age-matched non-epileptic controls (NEC) aimed to characterize the epileptic brain network using two functional measures, resting state-functional magnetic resonance imaging (rs-fMRI) and manganese-enhanced MRI (MEMRI) combined with morphometry, and to investigate potential brain network alterations, following long-term seizure activity. Methods Repeated rs-fMRI measurements at 9.4 T between 3 and 8 months of age were combined with MEMRI at the final time point of the study. We used graph theory analysis to infer community structure and global and local network parameters from rs-fMRI data and compared them to brain region-wise manganese accumulation patterns and deformation-based morphometry (DBM). Results Functional connectivity (FC) was generally higher in GAERS when compared to NEC. Global network parameters and community structure were similar in NEC and GAERS, suggesting efficiently functioning networks in both strains. No progressive FC changes were observed in epileptic animals. Network-based statistics (NBS) revealed stronger FC within the cortical community, including regions of association and sensorimotor cortex, and with basal ganglia and limbic regions in GAERS, irrespective of age. Higher manganese accumulation in GAERS than in NEC was observed at 8 months of age, consistent with higher overall rs-FC, particularly in sensorimotor cortex and association cortex regions. Functional measures showed less similarity in subcortical regions. Whole brain volumes of 8 months-old GAERS were higher when compared to age-matched NEC, and DBM revealed increased volumes of several association and sensorimotor cortex regions and of the thalamus. Discussion rs-fMRI, MEMRI, and volumetric data collectively suggest the significance of cortical networks in GAERS, which correlates with an increased fronto-central connectivity in childhood absence epilepsy (CAE). Our findings also verify involvement of basal ganglia and limbic regions. Epilepsy-related network alterations are already present in juvenile animals. Consequently, this early condition seems to play a greater role in dynamic brain function than chronic absence seizures.
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Affiliation(s)
- Lydia Wachsmuth
- Clinic of Radiology, University of Münster, Münster, Germany
| | - Leo Hebbelmann
- Clinic of Radiology, University of Münster, Münster, Germany
| | - Jutta Prade
- Department of Experimental and Clinical Pharmacology and Toxicology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Laura C. Kohnert
- Department of Experimental and Clinical Pharmacology and Toxicology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | | | | | - Thomas Budde
- Institute of Physiology I, University of Münster, Münster, Germany
| | - Andreas Hess
- Department of Experimental and Clinical Pharmacology and Toxicology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
- Department of Neuroradiology, University Hospital Erlangen, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
- FAU NeW – Research Center for New Bioactive Compounds, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Cornelius Faber
- Clinic of Radiology, University of Münster, Münster, Germany
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Monsivais H, Yeh CL, Edmondson A, Harold R, Snyder S, Wells EM, Schmidt-Wilcke T, Foti D, Zauber SE, Dydak U. Whole-brain mapping of increased manganese levels in welders and its association with exposure and motor function. Neuroimage 2024; 288:120523. [PMID: 38278427 PMCID: PMC11124758 DOI: 10.1016/j.neuroimage.2024.120523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 12/29/2023] [Accepted: 01/23/2024] [Indexed: 01/28/2024] Open
Abstract
Although manganese (Mn) is a trace metal essential for humans, chronic exposure to Mn can cause accumulation of this metal ion in the brain leading to an increased risk of neurological and neurobehavioral health effects. This is a concern for welders exposed to Mn through welding fumes. While brain Mn accumulation in occupational settings has mostly been reported in the basal ganglia, several imaging studies also revealed elevated Mn in other brain areas. Since Mn functions as a magnetic resonance imaging (MRI) T1 contrast agent, we developed a whole-brain MRI approach to map in vivo Mn deposition differences in the brains of non-exposed factory controls and exposed welders. This is a cross-sectional analysis of 23 non-exposed factory controls and 36 exposed full-time welders from the same truck manufacturer. We collected high-resolution 3D MRIs of brain anatomy and R1 relaxation maps to identify regional differences using voxel-based quantification (VBQ) and statistical parametric mapping. Furthermore, we investigated the associations between excess Mn deposition and neuropsychological and motor test performance. Our results indicate that: (1) Using whole-brain MRI relaxometry methods we can generate excess Mn deposition maps in vivo, (2) excess Mn accumulation due to occupational exposure occurs beyond the basal ganglia in cortical areas associated with motor and cognitive functions, (3) Mn likely diffuses along white matter tracts in the brain, and (4) Mn deposition in specific brain regions is associated with exposure (cerebellum and frontal cortex) and motor metrics (cerebellum and hippocampus).
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Affiliation(s)
| | - Chien-Lin Yeh
- School of Health Sciences, Purdue University, West Lafayette, IN, USA; Takeda Pharmaceutical Company Ltd, Cambridge, MA, USA
| | - Alex Edmondson
- Cincinnati Children's Hospital Medical Center, Imaging Research Center, Cincinnati, OH, USA; University of Cincinnati College of Medicine, Department of Environmental and Public Health Sciences, Cincinnati, OH USA
| | - Roslyn Harold
- Department of Psychological Sciences, Purdue University, West Lafayette, IN, USA
| | - Sandy Snyder
- School of Health Sciences, Purdue University, West Lafayette, IN, USA; Department of Speech, Language and Hearing Sciences, Purdue University, West Lafayette, IN, USA
| | - Ellen M Wells
- School of Health Sciences, Purdue University, West Lafayette, IN, USA; Department of Public Health, Purdue University, West Lafayette, IN, USA
| | - Tobias Schmidt-Wilcke
- Department of Neurology, St. Mauritius Therapieklinik, Meerbusch, Germany; Institute of Clinical Neuroscience and Medical Psychology, Universitätsklinikum Düsseldorf, Düsseldorf, Germany
| | - Dan Foti
- Department of Psychological Sciences, Purdue University, West Lafayette, IN, USA
| | - S Elizabeth Zauber
- Department of Neurology, Indiana University School of Medicine, Indianapolis, USA
| | - Ulrike Dydak
- School of Health Sciences, Purdue University, West Lafayette, IN, USA; Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN, USA.
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Bearer EL, Medina CS, Uselman TW, Jacobs RE. Harnessing axonal transport to map reward circuitry: Differing brain-wide projections from medial prefrontal cortical domains. Front Cell Dev Biol 2023; 11:1278831. [PMID: 38099294 PMCID: PMC10720719 DOI: 10.3389/fcell.2023.1278831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Accepted: 09/25/2023] [Indexed: 12/17/2023] Open
Abstract
Neurons project long axons that contact other distant neurons. Neurons in the medial prefrontal cortex project into the limbic system to regulate responses to reward or threat. Diminished neural activity in prefrontal cortex is associated with loss of executive function leading to drug use, yet the specific circuitry that mediate these effects is unknown. Different regions within the medial prefrontal cortex may project to differing limbic system nuclei. Here, we exploited the cell biology of intracellular membrane trafficking, fast axonal transport, to map projections from two adjacent medial prefrontal cortical regions. We used Mn(II), a calcium analog, to trace medial prefrontal cortical projections in the living animal by magnetic resonance imaging (MRI). Mn(II), a contrast agent for MRI, enters neurons through voltage-activated calcium channels and relies on kinesin-1 and amyloid-precursor protein to transport out axons to distal destinations. Aqueous MnCl2 together with fluorescent dextran (3--5 nL) was stereotactically injected precisely into two adjacent regions of the medial prefrontal cortex: anterior cingulate area (ACA) or infralimbic/prelimbic (IL/PL) region. Projections were traced, first live by manganese-enhanced MRI (MEMRI) at four time points in 3D, and then after fixation by microscopy. Data-driven unbiased voxel-wise statistical maps of aligned normalized MR images after either ACA or IL/PL injections revealed statistically significant progression of Mn(II) over time into deeper brain regions: dorsal striatum, globus pallidus, amygdala, hypothalamus, substantia nigra, dorsal raphe and locus coeruleus. Quantitative comparisons of these distal accumulations at 24 h revealed dramatic differences between ACA and IL/PL injection groups throughout the limbic system, and most particularly in subdomains of the hypothalamus. ACA projections targeted dorsomedial nucleus of the hypothalamus, posterior part of the periventricular region and mammillary body nuclei as well as periaqueductal gray, while IL/PL projections accumulated in anterior hypothalamic areas and lateral hypothalamic nuclei as well as amygdala. As hypothalamic subsegments relay CNS activity to the body, our results suggest new concepts about mind-body relationships and specific roles of distinct yet adjacent medial prefrontal cortical segments. Our MR imaging strategy, when applied to follow other cell biological processes in the living organism, will undoubtedly lead to an expanded perspective on how minute details of cellular processes influence whole body health and wellbeing.
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Affiliation(s)
- Elaine L. Bearer
- Department of Pathology, University of New Mexico Health Sciences Center, Albuquerque, NM, United States
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States
| | - Christopher S. Medina
- Department of Pathology, University of New Mexico Health Sciences Center, Albuquerque, NM, United States
| | - Taylor W. Uselman
- Department of Pathology, University of New Mexico Health Sciences Center, Albuquerque, NM, United States
| | - Russell E. Jacobs
- Zilkha Neurogenetic Institute, USC Keck School of Medicine, Los Angeles, CA, United States
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Liu Z, Xu K, Pan S, Zhang N, Wang D, Chen Y, Zhao Y, Wang S, Li J, Tong X. Manganese-enhanced magnetic resonance assessment of changes in hippocampal neural function after the treatment of radiation-induced brain injury with bone marrow mesenchymal stem cells. Brain Res Bull 2023; 204:110795. [PMID: 37863438 DOI: 10.1016/j.brainresbull.2023.110795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 10/03/2023] [Accepted: 10/17/2023] [Indexed: 10/22/2023]
Abstract
The role of bone marrow mesenchymal stem cells (BMSCs) in treating radiation-induced brain injury (RIBI) is not completely understood, and assessment methods to directly characterize neurological function are lacking. In this study, we aimed to evaluate the effects of BMSCs treatment on changes in hippocampal neural function in Sprague-Dawley(SD) rats with RIBI, and to evaluate the therapeutic effect of BMSCs by manganese-enhanced magnetic resonance imaging (MEMRI). First, we assessed cognitive function after RIBI treatment with BMSCs using the Morris water maze. Next, we used MEMRI at two time points to observe the treatment effect and explore the correlation between MEMRI and cognitive function. Finally, we evaluated the expression of specific hippocampal neurofunctional proteins, the ultrastructure of hippocampal nerves, and the histological changes in the hippocampus. After BMSCs treatment of RIBI, cognitive dysfunction improved significantly, the expression of hippocampal neurofunctional proteins was increased, the integrity of the hippocampal neural structure was protected, and nerve cell survival was enhanced. The improvement in neurological function was successfully detected by MEMRI, and MEMRI was highly correlated with cognitive function and histological changes. These results suggest that BMSCs treatment of RIBI is an optional modality, and MEMRI can be used for treatment evaluation.
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Affiliation(s)
- Zhanhong Liu
- College of Medical Technology, Qiqihar Medical University, Qiqihar 161006, China
| | - Kaina Xu
- College of Medical Technology, Qiqihar Medical University, Qiqihar 161006, China
| | - Shichao Pan
- College of Medical Technology, Qiqihar Medical University, Qiqihar 161006, China
| | - Na Zhang
- Department of Radiotherapy, the Third Affiliated Hospital of Qiqihar Medical University, Qiqihar 161006, China
| | - Dapeng Wang
- Department of Radiotherapy, the Third Affiliated Hospital of Qiqihar Medical University, Qiqihar 161006, China
| | - Ying Chen
- Department of Radiotherapy, the Third Affiliated Hospital of Qiqihar Medical University, Qiqihar 161006, China
| | - Yaru Zhao
- Department of Radiotherapy, the Third Affiliated Hospital of Qiqihar Medical University, Qiqihar 161006, China
| | - Siqi Wang
- Department of Radiotherapy, the Third Affiliated Hospital of Qiqihar Medical University, Qiqihar 161006, China
| | - Jing Li
- Department of Radiotherapy, the Third Affiliated Hospital of Qiqihar Medical University, Qiqihar 161006, China
| | - Xu Tong
- Department of Radiotherapy, the Third Affiliated Hospital of Qiqihar Medical University, Qiqihar 161006, China.
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Bearer EL, Medina CS, Uselman TW, Jacobs RE. Harnessing axonal transport to map reward circuitry: Differing brain-wide projections from medial forebrain domains. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.10.557059. [PMID: 38328063 PMCID: PMC10849663 DOI: 10.1101/2023.09.10.557059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
Neurons project long axons that contact other distant neurons. Projections can be mapped by hijacking endogenous membrane trafficking machinery by introducing tracers. To witness functional connections in living animals, we developed a tracer detectible by magnetic resonance imaging (MRI), Mn(II). Mn(II) relies on kinesin-1 and amyloid-precursor protein to travel out axons. Within 24h, projection fields of cortical neurons can be mapped brain-wide with this technology. MnCl2 was stereotactically injected either into anterior cingulate area (ACA) or into infralimbic/prelimbic (IL/PL) of medial forebrain (n=10-12). Projections were imaged, first by manganese-enhanced MRI (MEMRI) live, and then after fixation by microscopy. MR images were collected at 100μm isotropic resolution (~5 neurons) in 3D at four time points: before and at successive time points after injections. Images were preprocessed by masking non-brain tissue, followed by intensity scaling and spatial alignment. Actual injection locations, measured from post-injection MR images, were found to be 0.06, 0.49 and 0.84mm apart between cohorts, in R-L, A-P, and D-V directions respectively. Mn(II) enhancements arrived in hindbrains by 24h in both cohorts, while co-injected rhodamine dextran was not detectible beyond immediate subcortical projections. Data-driven unbiased voxel-wise statistical maps after ACA injections revealed significant progression of Mn(II) distally into deeper brain regions: globus pallidus, dorsal striatum, amygdala, hypothalamus, substantia nigra, dorsal raphe and locus coeruleus. Accumulation was quantified as a fraction of total volume of each segment containing significantly enhanced voxels (fractional accumulation volumes), and results visualized in column graphs. Unpaired t-tests between groups of brain-wide voxel-wise intensity profiling by either region of interest (ROI) measurements or statistical parametric mapping highlighted distinct differences in distal accumulation between injection sites, with ACA projecting to periaqueductal gray and IL/PL to basolateral amygdala (p<0.001 FDR). Mn(II) distal accumulations differed dramatically between injection groups in subdomains of the hypothalamus, with ACA targeting dorsal medial, periventricular region and mammillary body nuclei, while IL/PL went to anterior hypothalamic areas and lateral hypothalamic nuclei. Given that these hypothalamic subsegments communicate activity in the central nervous system to the body, these observations describing distinct forebrain projection fields will undoubtedly lead to newer insights in mind-body relationships.
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Affiliation(s)
- E. L. Bearer
- Department of Pathology, Univ. of New Mexico Health Sciences Center, Albuquerque, NM
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA
| | - C. S. Medina
- Department of Pathology, Univ. of New Mexico Health Sciences Center, Albuquerque, NM
| | - T. W. Uselman
- Department of Pathology, Univ. of New Mexico Health Sciences Center, Albuquerque, NM
| | - R. E. Jacobs
- Zilkha Neurogenetic Institute, USC Keck School of Medicine, Los Angeles, CA
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Orije JEMJ, Van der Linden A. A brain for all seasons: An in vivo MRI perspective on songbirds. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART A, ECOLOGICAL AND INTEGRATIVE PHYSIOLOGY 2022; 337:967-984. [PMID: 35989548 PMCID: PMC9804379 DOI: 10.1002/jez.2650] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 07/08/2022] [Accepted: 08/03/2022] [Indexed: 01/05/2023]
Abstract
Seasonality in songbirds includes not only reproduction but also seasonal changes in singing behavior and its neural substrate, the song control system (SCS). Prior research mainly focused on the role of sex steroids on this seasonal SCS neuroplasticity in males. In this review, we summarize the advances made in the field of seasonal neuroplasticity by applying in vivo magnetic resonance imaging (MRI) in male and female starlings, analyzing the entire brain, monitoring birds longitudinally and determining the neuronal correlates of seasonal variations in plasma hormone levels and song behavior. The first MRI studies in songbirds used manganese enhanced MRI to visualize the SCS in a living bird and validated previously described brain volume changes related to different seasons and testosterone. MRI studies with testosterone implantation established how the consequential boost in singing was correlated to structural changes in the SCS, indicating activity-induced neuroplasticity as song proficiency increased. Next, diffusion tensor MRI explored seasonal neuroplasticity in the entire brain, focusing on networks beyond the SCS, revealing that other sensory systems and even the cerebellum, which is important for the integration of sensory perception and song behavior, experience neuroplasticity starting in the photosensitive period. Functional MRI showed that olfactory, and auditory processing was modulated by the seasons. The convergence of seasonal variations in so many sensory and sensorimotor systems resembles multisensory neuroplasticity during the critical period early in life. This sheds new light on seasonal songbirds as a model for unlocking the brain by recreating seasonally the permissive circumstances for heightened neuroplasticity.
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Affiliation(s)
- Jasmien Ellen Maria Jozef Orije
- Department of Biomedical SciencesBio‐Imaging Lab, University of AntwerpAntwerpenBelgium,NEURO Research Centre of Excellence, University of AntwerpAntwerpenBelgium
| | - Annemie Van der Linden
- Department of Biomedical SciencesBio‐Imaging Lab, University of AntwerpAntwerpenBelgium,NEURO Research Centre of Excellence, University of AntwerpAntwerpenBelgium
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7
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Aguilar-Moreno A, Ortiz J, Concha L, Alcauter S, Paredes RG. Brain circuits activated by female sexual behavior evaluated by manganese enhanced magnetic resonance imaging. PLoS One 2022; 17:e0272271. [PMID: 35913950 PMCID: PMC9342731 DOI: 10.1371/journal.pone.0272271] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 07/15/2022] [Indexed: 12/02/2022] Open
Abstract
Magnetic resonance imaging (MRI) allows obtaining anatomical and functional information of the brain in the same subject at different times. Manganese-enhanced MRI (MEMRI) uses manganese ions to identify brain activity, although in high doses it might produce neurotoxic effects. Our aims were to identify a manganese dose that does not affect motivated behaviors such as sexual behavior, running wheel and the rotarod test. The second goal was to determine the optimal dose of chloride manganese (MnCl2) that will allow us to evaluate activation of brain regions after females mated controlling (pacing) the sexual interaction. To achieve that, two experiments were performed. In experiment 1 we evaluated the effects of two doses of MnCl2, 8 and 16 mg/kg. Subjects were injected with one of the doses of MnCl2 24 hours before the test on sessions 1, 5 and 10 and immediately thereafter scanned. Female sexual behavior, running wheel and the rotarod were evaluated once a week for 10 weeks. In experiment 2 we followed a similar procedure, but females paced the sexual interaction once a week for 10 weeks and were injected with one of the doses of MnCl2 24 hours before the test and immediately thereafter scanned on sessions 1, 5 and 10. The results of experiment 1 show that neither dose of MnCl2 induces alterations on sexual behavior, running wheel and rotarod. Experiment 2 demonstrated that MEMRI allow us to detect activation of different brain regions after sexual behavior, including the olfactory bulb (OB), the bed nucleus of the stria terminalis (BNST), the amygdala (AMG), the medial preoptic area (MPOA), the ventromedial hypothalamus (VMH), the nucleus accumbens (NAcc), the striatum (STR) and the hippocampus (Hipp) allowing the identification of changes in brain circuits activated by sexual behavior. The socio sexual circuit showed a higher signal intensity on session 5 than the reward circuit and the control groups indicating that even with sexual experience the activation of the reward circuit requires the activation of the socio sexual circuit. Our study demonstrates that MEMRI can be used repeatedly in the same subject to evaluate the activation of brain circuits after motivated behaviors and how can this activation change with experience.
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Affiliation(s)
| | - Juan Ortiz
- Instituto de Neurobiología, UNAM, Campus Juriquilla, Querétaro, México
| | - Luis Concha
- Instituto de Neurobiología, UNAM, Campus Juriquilla, Querétaro, México
| | - Sarael Alcauter
- Instituto de Neurobiología, UNAM, Campus Juriquilla, Querétaro, México
| | - Raúl G Paredes
- Instituto de Neurobiología, UNAM, Campus Juriquilla, Querétaro, México
- Escuela Nacional de Estudios Superiores, Unidad Juriquilla, UNAM, Querétaro, México
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8
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Uselman TW, Medina CS, Gray HB, Jacobs RE, Bearer EL. Longitudinal manganese-enhanced magnetic resonance imaging of neural projections and activity. NMR IN BIOMEDICINE 2022; 35:e4675. [PMID: 35253280 PMCID: PMC11064873 DOI: 10.1002/nbm.4675] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 10/19/2021] [Accepted: 12/07/2021] [Indexed: 06/14/2023]
Abstract
Manganese-enhanced magnetic resonance imaging (MEMRI) holds exceptional promise for preclinical studies of brain-wide physiology in awake-behaving animals. The objectives of this review are to update the current information regarding MEMRI and to inform new investigators as to its potential. Mn(II) is a powerful contrast agent for two main reasons: (1) high signal intensity at low doses; and (2) biological interactions, such as projection tracing and neural activity mapping via entry into electrically active neurons in the living brain. High-spin Mn(II) reduces the relaxation time of water protons: at Mn(II) concentrations typically encountered in MEMRI, robust hyperintensity is obtained without adverse effects. By selectively entering neurons through voltage-gated calcium channels, Mn(II) highlights active neurons. Safe doses may be repeated over weeks to allow for longitudinal imaging of brain-wide dynamics in the same individual across time. When delivered by stereotactic intracerebral injection, Mn(II) enters active neurons at the injection site and then travels inside axons for long distances, tracing neuronal projection anatomy. Rates of axonal transport within the brain were measured for the first time in "time-lapse" MEMRI. When delivered systemically, Mn(II) enters active neurons throughout the brain via voltage-sensitive calcium channels and clears slowly. Thus behavior can be monitored during Mn(II) uptake and hyperintense signals due to Mn(II) uptake captured retrospectively, allowing pairing of behavior with neural activity maps for the first time. Here we review critical information gained from MEMRI projection mapping about human neuropsychological disorders. We then discuss results from neural activity mapping from systemic Mn(II) imaged longitudinally that have illuminated development of the tonotopic map in the inferior colliculus as well as brain-wide responses to acute threat and how it evolves over time. MEMRI posed specific challenges for image data analysis that have recently been transcended. We predict a bright future for longitudinal MEMRI in pursuit of solutions to the brain-behavior mystery.
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Affiliation(s)
- Taylor W. Uselman
- University of New Mexico Health Sciences Center, Albuquerque, New Mexico, USA
| | | | - Harry B. Gray
- Beckman Institute, California Institute of Technology, Pasadena, California, USA
| | - Russell E. Jacobs
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Elaine L. Bearer
- University of New Mexico Health Sciences Center, Albuquerque, New Mexico, USA
- Beckman Institute, California Institute of Technology, Pasadena, California, USA
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Terry AV, Beck WD, Lin PC, Callahan PM, Rudic RD, Hamrick MW. Manganese-enhanced magnetic resonance imaging method detects age-related impairments in axonal transport in mice and attenuation of the impairments by a microtubule-stabilizing compound. Brain Res 2022; 1789:147947. [PMID: 35597325 DOI: 10.1016/j.brainres.2022.147947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 04/18/2022] [Accepted: 05/15/2022] [Indexed: 11/02/2022]
Abstract
In this study a manganese-enhanced magnetic resonance imaging (MEMRI) method was developed for mice for measuring axonal transport (AXT) rates in real time in olfactory receptor neurons, which project from the olfactory epithelium to the olfactory neuronal layer of the olfactory bulb. Using this MEMRI method, two major experiments were conducted: 1) an evaluation of the effects of age on AXT rates and 2) an evaluation of the brain-penetrant, microtubule-stabilizing agent, Epothilone D for effect on AXT rates in aged mice. In these studies, we improved upon previous MEMRI approaches to develop a method where real-time measurements (32 time points) of AXT rates in mice can be determined over a single (approximately 100 min) scanning session. In the age comparisons, AXT rates were significantly higher in young (mean age ∼4.0 months old) versus aged (mean age ∼24.5 months old) mice. Moreover, in aged mice, eight weeks of treatment with Epothilone D, (0.3 and 1.0 mg/kg) was associated with statistically significant increases in AXT rates compared to vehicle-treated subjects. These experiments conducted in a living mammalian model (i.e., wild type, C57BL/6 mice), using a new modified MEMRI method, thus provide further evidence that the process of aging leads to decreases in AXT rates in the brain and they further support the argument that microtubule-based therapeutic strategies designed to improve AXT rates have potential for age-related neurological disorders.
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Affiliation(s)
- Alvin V Terry
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, GA 30912, United States.
| | - Wayne D Beck
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, GA 30912, United States
| | - Ping-Chang Lin
- Research Computing Center, University of Chicago, Chicago, IL 60637, United States
| | - Patrick M Callahan
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, GA 30912, United States
| | - R Daniel Rudic
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, GA 30912, United States
| | - Mark W Hamrick
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA 30912, United States
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Bearer EL, Zhang X, Jacobs RE. Studying Axonal Transport in the Brain by Manganese-Enhanced Magnetic Resonance Imaging (MEMRI). METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2022; 2431:111-142. [PMID: 35412274 DOI: 10.1007/978-1-0716-1990-2_6] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
From the earliest notions of dynamic movements within the cell by Leeuwenhoek, intracellular transport in eukaryotes has been primarily explored by optical imaging. The giant axon of the squid became a prime experimental model for imaging transport due to its size, optical transparency, and physiological robustness. Even the biochemical basis of transport was identified using optical assays based on video microscopy of fractionated squid axoplasm. Discoveries about the dynamics and molecular components of the intracellular transport system continued in many model organisms that afforded experimental systems for optical imaging. Yet whether these experimental systems reflected a valid picture of axonal transport in the opaque mammalian brain was unknown.Magnetic resonance imaging (MRI) provides a non-destructive approach to peer into opaque tissues like the brain . The paramagnetic ion, manganese (MnII), gives a hyperintense signal in T1 weighted MRI that can serve as a marker for axonal transport. Mn(II) enters active neurons via voltage-gated calcium channels and is transported via microtubule motors down their axons by fast axonal transport. Clearance of Mn(II) is slow. Scanning live animals at successive time points reveals the dynamics of Mn(II) transport by detecting Mn(II)-induced intensity increases or accumulations along a known fiber tract, such as the optic nerve or hippocampal-forebrain projections. Mn(II)-based tract tracing also reveals projections even when not in fiber bundles, such as projections in the olfactory system or from medial prefrontal cortex into midbrain and brain stem. The rate of Mn(II) accumulation, detected as increased signal intensity by MR, serves as a proxy for transport rates. Here we describe the method for measuring transport rates and projections by mangeses-enhanced magnetic resonance imaging, MEMRI.
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Affiliation(s)
- Elaine L Bearer
- Department Pathology, University of New Mexico Health Sciences Center, Albuquerque, NM, USA.
- Biology and Biological Engineering and the Beckman Institute, California Institute of Technology, Pasadena, CA, USA.
| | - Xiaowei Zhang
- Department of Radiology, UC San Diego School of Medicine, San Diego, CA, USA
| | - Russell E Jacobs
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
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11
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Ghosh S, Li N, Schwalm M, Bartelle BB, Xie T, Daher JI, Singh UD, Xie K, DiNapoli N, Evans NB, Chung K, Jasanoff A. Functional dissection of neural circuitry using a genetic reporter for fMRI. Nat Neurosci 2022; 25:390-398. [PMID: 35241803 PMCID: PMC9203076 DOI: 10.1038/s41593-022-01014-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 01/14/2022] [Indexed: 12/16/2022]
Abstract
The complex connectivity of the mammalian brain underlies its function, but understanding how interconnected brain regions interact in neural processing remains a formidable challenge. Here we address this problem by introducing a genetic probe that permits selective functional imaging of distributed neural populations defined by viral labeling techniques. The probe is an engineered enzyme that transduces cytosolic calcium dynamics of probe-expressing cells into localized hemodynamic responses that can be specifically visualized by functional magnetic resonance imaging. Using a viral vector that undergoes retrograde transport, we apply the probe to characterize a brain-wide network of presynaptic inputs to the striatum activated in a deep brain stimulation paradigm in rats. The results reveal engagement of surprisingly diverse projection sources and inform an integrated model of striatal function relevant to reward behavior and therapeutic neurostimulation approaches. Our work thus establishes a strategy for mechanistic analysis of multiregional neural systems in the mammalian brain.
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Affiliation(s)
- Souparno Ghosh
- Department of Biological Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139
| | - Nan Li
- Department of Biological Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139
| | - Miriam Schwalm
- Department of Biological Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139
| | - Benjamin B. Bartelle
- Department of Biological Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139
| | - Tianshu Xie
- Department of Biological Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139
| | - Jade I. Daher
- Department of Biological Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139,Department of Brain & Cognitive Sciences, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139
| | - Urvashi D. Singh
- Department of Biological Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139
| | - Katherine Xie
- Institute for Medical Engineering & Science, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139
| | - Nicholas DiNapoli
- Institute for Medical Engineering & Science, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139
| | - Nicholas B. Evans
- Institute for Medical Engineering & Science, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139
| | - Kwanghun Chung
- Department of Brain & Cognitive Sciences, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139,Institute for Medical Engineering & Science, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139,Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139,Broad Institute of MIT and Harvard, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139
| | - Alan Jasanoff
- Department of Biological Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139,Department of Brain & Cognitive Sciences, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139,Department of Nuclear Science & Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139,Correspondence to AJ, phone: 617-452-2538,
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12
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Wang X, Li R, He R, Fang F. Effects of repeated manganese treatment on proton magnetic resonance spectra of the globus pallidus in rat brain. NMR IN BIOMEDICINE 2022; 35:e4617. [PMID: 34562038 DOI: 10.1002/nbm.4617] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 08/25/2021] [Accepted: 08/29/2021] [Indexed: 06/13/2023]
Abstract
Excessive manganese is neurotoxic, which means that it can affect the concentrations of metabolite in 1 H MRS. In addition, manganese is paramagnetic and it may influence the relaxation times of the metabolite. The aim of this study is to assess the sensitivity of the metabolite relaxation properties and concentrations to exogenous manganese deposition in the globus pallidus (GP) of rat brain after repeated manganese injection. Proton magnetic resonance spectroscopy (1 H MRS) experiments in vivo and ex vivo were carried out to evaluate the changes in the metabolite concentration and the major metabolite relaxation times, and histological experiments were also performed after repeated manganese administration. Only the T1 value for N-acetylaspartate (NAA) of the GP was significantly reduced after 1 day of manganese injection compared with that of the control group (p < 0.025). The T1 and T2 values for NAA and total creatine (tCr) (p < 0.025), along with the amounts of NAA, tCr, myo-inositol, choline, and glutamate (p < 0.0086) in the GP, were all significantly decreased after 5 days of manganese administration compared with that of the control group. The changes in the concentration and relaxation properties of NAA and tCr in the GP of rat brain indicated that manganese represented paramagnetism and neurotoxicity after repeated administration. Accurate knowledge of relaxation properties and concentrations of NAA and tCr in this study could help appropriate selection of sequence parameters to improve the ability to distinguish the brain regions affected in cases of manganese poisoning.
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Affiliation(s)
- Xuxia Wang
- State Key Laboratory of Magnetic Resonance and Atomic Molecular Physics, National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Ronghui Li
- State Key Laboratory of Magnetic Resonance and Atomic Molecular Physics, National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, China
| | - Rui He
- State Key Laboratory of Magnetic Resonance and Atomic Molecular Physics, National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, China
| | - Fang Fang
- State Key Laboratory of Magnetic Resonance and Atomic Molecular Physics, National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, China
- University of Chinese Academy of Sciences, Beijing, China
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13
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Liu C, Han G, Hu B, Geng F, Liu M, Dai S, Yang Y. Fast Screening of Coal Fly Ash with Potential for Rare Earth Element Recovery by Electron Paramagnetic Resonance Spectroscopy. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:16716-16722. [PMID: 34890179 DOI: 10.1021/acs.est.1c06658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Rare earth elements (REYs) are in increasing global demand, but their mining is costly and environmentally destructive. Coal fly ash (CFA) is a promising alternative source of REYs, but it is necessary to identify CFA with sufficiently high REY concentrations. This study proposes the use of electron paramagnetic resonance (EPR) spectroscopy as part of a simple method to identify CFAs with adequate REY concentrations. The EPR spectra of CFA samples taken from 186 Chinese commercial coal-fired power plants were analyzed. The results suggest that CFAs without evident 6-fold resonances are worth recycling (REY concentrations of 416 ± 108 mg/kg), while those with conspicuous 6-fold resonances are not worth recycling (REY concentrations of 55 ± 26 mg/kg). This is probably due to isomorphic substitution of Ca(II) for Mn(II) and REY(III), resulting in low concentrations of Mn(II) and REY(III) in Ca-rich CFAs. This EPR evaluation method does not require specialized sample preparation, professional skills, or secondary data analysis and has potential global significance in the fast screening of CFAs with REY-recycling potential.
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Affiliation(s)
- Chang Liu
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographical Sciences, East China Normal University, Shanghai 200241, China
| | - Guoling Han
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographical Sciences, East China Normal University, Shanghai 200241, China
| | - Bingwen Hu
- State Key Laboratory of Precision Spectroscopy, Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Electronic Science, East China Normal University, Shanghai 200062, China
| | - Fushan Geng
- State Key Laboratory of Precision Spectroscopy, Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Electronic Science, East China Normal University, Shanghai 200062, China
| | - Min Liu
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographical Sciences, East China Normal University, Shanghai 200241, China
| | - Shifeng Dai
- State Key Laboratory of Coal Resources and Safe Mining, China University of Mining and Technology (Beijing), Beijing 100083, China
| | - Yi Yang
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographical Sciences, East China Normal University, Shanghai 200241, China
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14
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Yang J, Gao J, Han D, Li Q, Liao C, Li J, Wang R, Luo Y. Hippocampal changes in inflammasomes, apoptosis, and MEMRI after radiation-induced brain injury in juvenile rats. Radiat Oncol 2020; 15:78. [PMID: 32276638 PMCID: PMC7147014 DOI: 10.1186/s13014-020-01525-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Accepted: 03/26/2020] [Indexed: 01/02/2023] Open
Abstract
PURPOSE The aim of this study was to characterize changes in hippocampal inflammasomes, pyroptosis and apoptosis in juvenile rats after brain irradiation and to assess whether manganese-enhanced magnetic resonance imaging (MEMRI) reflected those changes. MATERIALS AND METHODS Four-week-old male Sprague-Dawley rats received a whole-brain radiation dose of 15 Gy or 25 Gy. Hippocampal inflammasomes and apoptosis were measured using Western blot analysis at 4 days and 8 weeks after irradiation. MEMRI and magnetic resonance spectroscopy (MRS) were performed at the same time points. RESULTS Neither the 15 Gy nor 25 Gy group showed changes in the expression of inflammasome proteins absent in melanoma 2 (AIM2), gasdermin-D (GSDMD), nucleotide oligomerization domain-like receptor protein 1 (NLRP1) and NLRP3 at 4 days or 8 weeks after radiation injury (P > 0.05). Furthermore, the expression levels of the inflammatory cytokines interleukin-1β (IL-1β) and IL-18 were not significantly different among the groups (P > 0.05). The expression levels of cleaved caspase-1 and -3, indicators of apoptosis, were higher in the irradiation groups than in the control group at 4 days post irradiation, especially for caspase-3 (P < 0.05), but this increase was slightly attenuated at 8 weeks after radiation injury. Four days post irradiation, the MEMRI signal intensity (SI) in the irradiation groups, especially the 25 Gy group, was significantly lower than that in the control group (P < 0.05). Eight weeks after radiation injury, the SI of the 15 Gy group and the 25 Gy group recovered by different degrees, but the SI of the 25 Gy group was still significantly lower than that of the control group (P < 0.05). On day 4 post irradiation, the metabolic ratio of N-acetylaspartate (NAA) to creatine (Cr) in the 15 Gy group and 25 Gy group was significantly lower than that in the control group (P < 0.05). The NAA/Cr ratio in the 15 Gy group recovered to control levels at 8 weeks (P > 0.05), but the NAA/Cr ratio in the 25 Gy group remained significantly lower than that in the control group (P < 0.05). CONCLUSION Radiation-induced brain injury is dose-dependently associated with apoptosis but not inflammasomes or pyroptosis, and the change in apoptosis can be detected by MEMRI.
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Affiliation(s)
- Jun Yang
- Department of Radiology, The Third Affiliated Hospital of Kunming Medical University, Yunnan Cancer Hospital & Cancer Center, No. 519 Kunzhou Road, Xishan District, Kunming, 650118, Yunnan, P.R. China. .,Department of Medical Imaging, The First Affiliated Hospital of Kunming Medical University, No. 295 Xichang Road, Kunming, 650032, Yunnan, PR China.
| | - Jingyan Gao
- Department of Radiation Oncology, The Third Affiliated Hospital of Kunming Medical University, Yunnan Cancer Hospital & Cancer Center, No. 519 Kunzhou Road, Xishan District, Kunming, 650118, Yunnan, P.R. China
| | - Dan Han
- Department of Medical Imaging, The First Affiliated Hospital of Kunming Medical University, No. 295 Xichang Road, Kunming, 650032, Yunnan, PR China
| | - Qinqing Li
- Department of Radiology, The Third Affiliated Hospital of Kunming Medical University, Yunnan Cancer Hospital & Cancer Center, No. 519 Kunzhou Road, Xishan District, Kunming, 650118, Yunnan, P.R. China
| | - Chengde Liao
- Department of Radiology, The Third Affiliated Hospital of Kunming Medical University, Yunnan Cancer Hospital & Cancer Center, No. 519 Kunzhou Road, Xishan District, Kunming, 650118, Yunnan, P.R. China
| | - Jindan Li
- Department of Radiology, The Third Affiliated Hospital of Kunming Medical University, Yunnan Cancer Hospital & Cancer Center, No. 519 Kunzhou Road, Xishan District, Kunming, 650118, Yunnan, P.R. China
| | - Rui Wang
- Department of Radiology, The Third Affiliated Hospital of Kunming Medical University, Yunnan Cancer Hospital & Cancer Center, No. 519 Kunzhou Road, Xishan District, Kunming, 650118, Yunnan, P.R. China
| | - Yueyuan Luo
- Department of Radiology, The Third Affiliated Hospital of Kunming Medical University, Yunnan Cancer Hospital & Cancer Center, No. 519 Kunzhou Road, Xishan District, Kunming, 650118, Yunnan, P.R. China
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15
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Alambyan V, Pace J, Sukpornchairak P, Yu X, Alnimir H, Tatton R, Chitturu G, Yarlagadda A, Ramos-Estebanez C. Imaging Guidance for Therapeutic Delivery: The Dawn of Neuroenergetics. Neurotherapeutics 2020; 17:522-538. [PMID: 32240530 PMCID: PMC7283376 DOI: 10.1007/s13311-020-00843-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Modern neurocritical care relies on ancillary diagnostic testing in the form of multimodal monitoring to address acute changes in the neurological homeostasis. Much of our armamentarium rests upon physiological and biochemical surrogates of organ or regional level metabolic activity, of which a great deal is invested at the metabolic-hemodynamic-hydrodynamic interface to rectify the traditional intermediaries of glucose consumption. Despite best efforts to detect cellular neuroenergetics, current modalities cannot appreciate the intricate coupling between astrocytes and neurons. Invasive monitoring is not without surgical complication, and noninvasive strategies do not provide an adequate spatial or temporal resolution. Without knowledge of the brain's versatile behavior in specific metabolic states (glycolytic vs oxidative), clinical practice would lag behind laboratory empiricism. Noninvasive metabolic imaging represents a new hope in delineating cellular, nigh molecular level energy exchange to guide targeted management in a diverse array of neuropathology.
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Affiliation(s)
- Vilakshan Alambyan
- Department of Neurology, Albert Einstein Medical Center, Philadelphia, Pennsylvania, USA
| | - Jonathan Pace
- Neurological Institute, University Hospitals Cleveland Medical Center, Case Western Reserve University, Cleveland, Ohio, USA
| | - Persen Sukpornchairak
- Neurological Institute, University Hospitals Cleveland Medical Center, Case Western Reserve University, Cleveland, Ohio, USA
| | - Xin Yu
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, USA
- Department of Radiology, Case Western Reserve University, Cleveland, Ohio, USA
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, Ohio, USA
| | - Hamza Alnimir
- Neurological Institute, University Hospitals Cleveland Medical Center, Case Western Reserve University, Cleveland, Ohio, USA
| | - Ryan Tatton
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, USA
| | - Gautham Chitturu
- Department of Arts and Sciences, Case Western Reserve University, Cleveland, Ohio, USA
| | - Anisha Yarlagadda
- Department of Arts and Sciences, Case Western Reserve University, Cleveland, Ohio, USA
| | - Ciro Ramos-Estebanez
- Neurological Institute, University Hospitals Cleveland Medical Center, Case Western Reserve University, Cleveland, Ohio, USA.
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16
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Vanderweyen DC, Theaud G, Sidhu J, Rheault F, Sarubbo S, Descoteaux M, Fortin D. The role of diffusion tractography in refining glial tumor resection. Brain Struct Funct 2020; 225:1413-1436. [PMID: 32180019 DOI: 10.1007/s00429-020-02056-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2019] [Accepted: 02/28/2020] [Indexed: 12/14/2022]
Abstract
Primary brain tumors are notoriously hard to resect surgically. Due to their infiltrative nature, finding the optimal resection boundary without damaging healthy tissue can be challenging. One potential tool to help make this decision is diffusion-weighted magnetic resonance imaging (dMRI) tractography. dMRI exploits the diffusion of water molecule along axons to generate a 3D modelization of the white matter bundles in the brain. This feature is particularly useful to visualize how a tumor affects its surrounding white matter and plan a surgical path. This paper reviews the different ways in which dMRI can be used to improve brain tumor resection, its benefits and also its limitations. We expose surgical tools that can be paired with dMRI to improve its impact on surgical outcome, such as loading the 3D tractography in the neuronavigation system and direct electrical stimulation to validate the position of the white matter bundles of interest. We also review articles validating dMRI findings using other anatomical investigation techniques, such as postmortem dissections, manganese-enhanced MRI, electrophysiological stimulations, and phantom studies with known ground truth. We will be discussing the areas of the brain where dMRI performs well and where the future challenges are. We will conclude this review with suggestions and take home messages for neurosurgeons, tractographers, and vendors for advancing the field and on how to benefit from tractography's use in clinical practice.
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Affiliation(s)
- Davy Charles Vanderweyen
- Department of Surgery, Division of Neurosurgery, Faculty of Medicine, University of Sherbrooke, 3001 12 Ave N, Sherbrooke, QC, J1H 5H3, Canada.
| | - Guillaume Theaud
- Sherbrooke Connectivity Imaging Lab (SCIL), Computer Science Department, University of Sherbrooke, 2500 Boulevard Université, Sherbrooke, QC, J1K2R1, Canada
| | - Jasmeen Sidhu
- Sherbrooke Connectivity Imaging Lab (SCIL), Computer Science Department, University of Sherbrooke, 2500 Boulevard Université, Sherbrooke, QC, J1K2R1, Canada
| | - François Rheault
- Sherbrooke Connectivity Imaging Lab (SCIL), Computer Science Department, University of Sherbrooke, 2500 Boulevard Université, Sherbrooke, QC, J1K2R1, Canada
| | - Silvio Sarubbo
- Division of Neurosurgery, Emergency Area, Structural and Functional Connectivity Lab Project, "S. Chiara" Hospital, Azienda Provinciale Per I Servizi Sanitari (APSS), Trento, Italy
| | - Maxime Descoteaux
- Sherbrooke Connectivity Imaging Lab (SCIL), Computer Science Department, University of Sherbrooke, 2500 Boulevard Université, Sherbrooke, QC, J1K2R1, Canada
| | - David Fortin
- Department of Surgery, Division of Neurosurgery, Faculty of Medicine, University of Sherbrooke, 3001 12 Ave N, Sherbrooke, QC, J1H 5H3, Canada
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17
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Yang J, Li Q. Manganese-Enhanced Magnetic Resonance Imaging: Application in Central Nervous System Diseases. Front Neurol 2020; 11:143. [PMID: 32161572 PMCID: PMC7052353 DOI: 10.3389/fneur.2020.00143] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 02/07/2020] [Indexed: 12/12/2022] Open
Abstract
Manganese-enhanced magnetic resonance imaging (MEMRI) relies on the strong paramagnetism of Mn2+. Mn2+ is a calcium ion analog and can enter excitable cells through voltage-gated calcium channels. Mn2+ can be transported along the axons of neurons via microtubule-based fast axonal transport. Based on these properties, MEMRI is used to describe neuroanatomical structures, monitor neural activity, and evaluate axonal transport rates. The application of MEMRI in preclinical animal models of central nervous system (CNS) diseases can provide more information for the study of disease mechanisms. In this article, we provide a brief review of MEMRI use in CNS diseases ranging from neurodegenerative diseases to brain injury and spinal cord injury.
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Affiliation(s)
- Jun Yang
- Department of Radiology, The Third Affiliated Hospital of Kunming Medical University, Yunnan Cancer Hospital & Cancer Center, Kunming, China
| | - Qinqing Li
- Department of Radiology, The Third Affiliated Hospital of Kunming Medical University, Yunnan Cancer Hospital & Cancer Center, Kunming, China
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18
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Yang J, Li Q, Han D, Liao C, Wang P, Gao J, Xu Z, Liu Y. Radiation-induced impairment of optic nerve axonal transport in tree shrews and rats monitored by longitudinal manganese-enhanced MRI. Neurotoxicology 2020; 77:145-154. [PMID: 31987859 DOI: 10.1016/j.neuro.2020.01.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 01/22/2020] [Accepted: 01/22/2020] [Indexed: 11/30/2022]
Abstract
PURPOSE Radiation-induced optic neuropathy (RION) is a serious complication that occurs after radiation therapy of tumors in the vicinity of the optic nerve, yet its mechanism and imaging features are poorly understood. In this study, we employed manganese-enhanced MRI (MEMRI) to assess optic nerve axonal transport in tree shrews and rats after irradiation. MATERIALS AND METHODS A comparison of normal visual projections in tree shrews and rats was conducted by intravitreal MnCl2 injection followed by MRI. Adult male tree shrews and rats received a total dose of 20 Gy delivered in two fractions (10 Gy per fraction) within 5 days. Longitudinal MEMRI was conducted 5, 10, 20 and 30 weeks after radiation. At the end of observation, motor proteins involved in axonal transport were detected by western blotting, and the axon cytoskeleton was assessed by immunofluorescence. RESULTS The eyeballs, lens sizes, vitreous volumes, optic nerves and superior colliculi of tree shrews were significantly larger than those of rats on MEMRI (P < 0.05). The Mn2+-enhancement of the optic nerve showed no significant changes at 5 and 10 weeks (P > 0.05) but decreased gradually from 20 to 30 weeks postirradiation (P < 0.05). The enhancement of the superior colliculus gradually decreased from 5 weeks to 30 weeks, and the decrease was most significant at 30 weeks (P < 0.05). The levels of the motor proteins cytoplasmic dynein-1, kinesin-1 and kinesin-2 in the experimental group were significantly decreased (P < 0.05). The immunofluorescence results showed that the α-tubulin, β-tubulin and SMI 31 levels in the experimental groups and control groups were not significantly different (P > 0.05). CONCLUSION Tree shrews show great advantages in visual neuroscience research involving MEMRI. The main cause of the decline in axonal transport in RION is an insufficient level of motor protein rather than damage to the axonal cytoskeletal structure. Longitudinal MEMRI can be used to detect changes in axonal transport function and to observe the relatively intact axon structure from the early to late stages after radiation administration.
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Affiliation(s)
- Jun Yang
- Department of Radiology. The Third Affiliated Hospital of Kunming Medical University, Yunnan Cancer Hospital & Cancer Center, No. 519 Kunzhou Road, Xishan District, Kunming, 650118, Yunnan, PR China.
| | - Qinqing Li
- Department of Radiology. The Third Affiliated Hospital of Kunming Medical University, Yunnan Cancer Hospital & Cancer Center, No. 519 Kunzhou Road, Xishan District, Kunming, 650118, Yunnan, PR China
| | - Dan Han
- Department of Medical Imaging. The First Affiliated Hospital of Kunming Medical University, No. 295 Xichang Road, Kunming, 650032, Yunnan, PR China
| | - Chengde Liao
- Department of Radiology. The Third Affiliated Hospital of Kunming Medical University, Yunnan Cancer Hospital & Cancer Center, No. 519 Kunzhou Road, Xishan District, Kunming, 650118, Yunnan, PR China
| | - Pengfei Wang
- Department of Key Laboratory. The Second Affiliated Hospital of Kunming Medical University, No. 374 Dianmian Road, Kunming, 650101, Yunnan, PR China
| | - Jingyan Gao
- Department of Radiation Oncology. The Third Affiliated Hospital of Kunming Medical University, Yunnan Cancer Hospital & Cancer Center, No. 519 Kunzhou Road, Xishan District, Kunming, 650118, Yunnan, PR China
| | - Zeyan Xu
- Department of Radiology. The Third Affiliated Hospital of Kunming Medical University, Yunnan Cancer Hospital & Cancer Center, No. 519 Kunzhou Road, Xishan District, Kunming, 650118, Yunnan, PR China
| | - Yifan Liu
- Department of Radiology. The Third Affiliated Hospital of Kunming Medical University, Yunnan Cancer Hospital & Cancer Center, No. 519 Kunzhou Road, Xishan District, Kunming, 650118, Yunnan, PR China
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19
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Surana S, Villarroel‐Campos D, Lazo OM, Moretto E, Tosolini AP, Rhymes ER, Richter S, Sleigh JN, Schiavo G. The evolution of the axonal transport toolkit. Traffic 2019; 21:13-33. [DOI: 10.1111/tra.12710] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 10/16/2019] [Accepted: 10/17/2019] [Indexed: 12/11/2022]
Affiliation(s)
- Sunaina Surana
- Department of Neuromuscular Diseases, UCL Queen Square Institute of NeurologyUniversity College London London UK
| | - David Villarroel‐Campos
- Department of Neuromuscular Diseases, UCL Queen Square Institute of NeurologyUniversity College London London UK
| | - Oscar M. Lazo
- Department of Neuromuscular Diseases, UCL Queen Square Institute of NeurologyUniversity College London London UK
- UK Dementia Research InstituteUniversity College London London UK
| | - Edoardo Moretto
- UK Dementia Research InstituteUniversity College London London UK
| | - Andrew P. Tosolini
- Department of Neuromuscular Diseases, UCL Queen Square Institute of NeurologyUniversity College London London UK
| | - Elena R. Rhymes
- Department of Neuromuscular Diseases, UCL Queen Square Institute of NeurologyUniversity College London London UK
| | - Sandy Richter
- Department of Neuromuscular Diseases, UCL Queen Square Institute of NeurologyUniversity College London London UK
| | - James N. Sleigh
- Department of Neuromuscular Diseases, UCL Queen Square Institute of NeurologyUniversity College London London UK
- UK Dementia Research InstituteUniversity College London London UK
| | - Giampietro Schiavo
- Department of Neuromuscular Diseases, UCL Queen Square Institute of NeurologyUniversity College London London UK
- UK Dementia Research InstituteUniversity College London London UK
- Discoveries Centre for Regenerative and Precision MedicineUniversity College London London UK
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20
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Khodaei A, Malek M, Hosseini HRM, Delavari H H, Vahdatkhah P. A study on the Concentration‐dependent Relaxometric Transition in Manganese Oxide Nanocolloid as MRI Contrast Agent. ChemistrySelect 2019. [DOI: 10.1002/slct.201901760] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Azin Khodaei
- Department of Materials Science and EngineeringSharif University of Technology Azadi Ave. 14588–9694 Tehran Iran
| | - Mahrooz Malek
- Department of Radiology, Medical Imaging CenterAdvanced Diagnostic and Interventional Radiology Research Center (ADIR)Tehran University of Medical Sciences, Imam Khomeini Hospital Tehran Iran
| | - Hamid Reza Madaah Hosseini
- Department of Materials Science and EngineeringSharif University of Technology Azadi Ave. 14588–9694 Tehran Iran
| | - Hamid Delavari H
- Department of Materials EngineeringTarbiat Modares University Tehran Iran
| | - Parisa Vahdatkhah
- Department of Materials Science and EngineeringSharif University of Technology Azadi Ave. 14588–9694 Tehran Iran
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21
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Chen Y, Pais-Roldan P, Chen X, Frosz MH, Yu X. MRI-guided robotic arm drives optogenetic fMRI with concurrent Ca 2+ recording. Nat Commun 2019; 10:2536. [PMID: 31182714 PMCID: PMC6557837 DOI: 10.1038/s41467-019-10450-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2018] [Accepted: 05/11/2019] [Indexed: 12/16/2022] Open
Abstract
Optical fiber-mediated optogenetic activation and neuronal Ca2+ recording in combination with fMRI provide a multi-modal fMRI platform. Here, we developed an MRI-guided robotic arm (MgRA) as a flexible positioning system with high precision to real-time assist optical fiber brain intervention for multi-modal animal fMRI. Besides the ex vivo precision evaluation, we present the highly reliable brain activity patterns in the projected basal forebrain regions upon MgRA-driven optogenetic stimulation in the lateral hypothalamus. Also, we show the step-wise optical fiber targeting thalamic nuclei and map the region-specific functional connectivity with whole-brain fMRI accompanied by simultaneous calcium recordings to specify its circuit-specificity. The MgRA also guides the real-time microinjection to specific deep brain nuclei, which is demonstrated by an Mn-enhanced MRI method. The MgRA represents a clear advantage over the standard stereotaxic-based fiber implantation and opens a broad avenue to investigate the circuit-specific functional brain mapping with the multi-modal fMRI platform.
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Affiliation(s)
- Yi Chen
- Research Group of Translational Neuroimaging and Neural Control, High-Field Magnetic Resonance, Max Planck Institute for Biological Cybernetics, 72076, Tuebingen, Germany
- Graduate Training Centre of Neuroscience, University of Tuebingen, 72076, Tuebingen, Germany
| | - Patricia Pais-Roldan
- Research Group of Translational Neuroimaging and Neural Control, High-Field Magnetic Resonance, Max Planck Institute for Biological Cybernetics, 72076, Tuebingen, Germany
- Graduate Training Centre of Neuroscience, University of Tuebingen, 72076, Tuebingen, Germany
| | - Xuming Chen
- Research Group of Translational Neuroimaging and Neural Control, High-Field Magnetic Resonance, Max Planck Institute for Biological Cybernetics, 72076, Tuebingen, Germany
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan University, 430060 Wuhan, China
| | - Michael H Frosz
- Max Planck Institute for the Science of Light, 91058, Erlangen, Germany
| | - Xin Yu
- Research Group of Translational Neuroimaging and Neural Control, High-Field Magnetic Resonance, Max Planck Institute for Biological Cybernetics, 72076, Tuebingen, Germany.
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, 02129, USA.
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22
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Badea A, Delpratt NA, Anderson RJ, Dibb R, Qi Y, Wei H, Liu C, Wetsel WC, Avants BB, Colton C. Multivariate MR biomarkers better predict cognitive dysfunction in mouse models of Alzheimer's disease. Magn Reson Imaging 2019; 60:52-67. [PMID: 30940494 DOI: 10.1016/j.mri.2019.03.022] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Revised: 03/26/2019] [Accepted: 03/27/2019] [Indexed: 12/15/2022]
Abstract
To understand multifactorial conditions such as Alzheimer's disease (AD) we need brain signatures that predict the impact of multiple pathologies and their interactions. To help uncover the relationships between pathology affected brain circuits and cognitive markers we have used mouse models that represent, at least in part, the complex interactions altered in AD, while being raised in uniform environments and with known genotype alterations. In particular, we aimed to understand the relationship between vulnerable brain circuits and memory deficits measured in the Morris water maze, and we tested several predictive modeling approaches. We used in vivo manganese enhanced MRI traditional voxel based analyses to reveal regional differences in volume (morphometry), signal intensity (activity), and magnetic susceptibility (iron deposition, demyelination). These regions included hippocampus, olfactory areas, entorhinal cortex and cerebellum, as well as the frontal association area. The properties of these regions, extracted from each of the imaging markers, were used to predict spatial memory. We next used eigenanatomy, which reduces dimensionality to produce sets of regions that explain the variance in the data. For each imaging marker, eigenanatomy revealed networks underpinning a range of cognitive functions including memory, motor function, and associative learning, allowing the detection of associations between context, location, and responses. Finally, the integration of multivariate markers in a supervised sparse canonical correlation approach outperformed single predictor models and had significant correlates to spatial memory. Among a priori selected regions, expected to play a role in memory dysfunction, the fornix also provided good predictors, raising the possibility of investigating how disease propagation within brain networks leads to cognitive deterioration. Our cross-sectional results support that modeling approaches integrating multivariate imaging markers provide sensitive predictors of AD-like behaviors. Such strategies for mapping brain circuits responsible for behaviors may help in the future predict disease progression, or response to interventions.
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Affiliation(s)
- Alexandra Badea
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, NC, USA; Department of Neurology, Duke University Medical Center, Durham, NC, USA; Brain Imaging and Analysis Center, Duke University, Durham, NC, USA.
| | - Natalie A Delpratt
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, NC, USA
| | - R J Anderson
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, NC, USA
| | - Russell Dibb
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, NC, USA
| | - Yi Qi
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, NC, USA
| | - Hongjiang Wei
- Institute for Medical Imaging Technology, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China.
| | - Chunlei Liu
- Department of Electrical Engineering and Computer Science, University of California, Berkeley, CA, USA
| | - William C Wetsel
- Department of Psychiatry and Behavioral Sciences, Cell Biology, Neurobiology, Duke University Medical Center, Durham, NC, USA
| | - Brian B Avants
- Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA, USA
| | - Carol Colton
- Department of Neurology, Duke University Medical Center, Durham, NC, USA
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23
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Kotenkova E, Romachenko A, Ambaryan A, Maltsev A. Effect of early experience on neuronal and behavioral responses to con- and heterospecific odors in closely related Mus taxa: epigenetic contribution in formation of precopulatory isolation. BMC Evol Biol 2019; 19:51. [PMID: 30813903 PMCID: PMC6391773 DOI: 10.1186/s12862-019-1373-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND The most effective learning occurs during sensitive periods. Olfactory plasticity to main social olfactory cues is limited to a critical period to a large degree. The objective was to evaluate the influence of early olfactory experience on the behavioral and neuronal responses of males to con- and heterospecific odors of receptive females in two species, M. musculus (subspecies musculus, wagneri) and M. spicilegus, and thus to determine the potential role of epigenetic contribution in the formation of precopulatory isolation. RESULTS Males were reciprocally cross-fostered shortly after the birth and were tested for response to con- and heterospecific urine odors of estrus females using two-choice tests at 70-85 days of age. Neuronal activity of non- and cross-fostered males was evaluated at 90-110 days of age in the MOB and AOB to con- and heterospecific female odor using fMRI (MEMRI). Non-cross-fostered males of three taxa demonstrated a strong preference for odor of conspecific females compared to odor of heterospecific ones. Spicilegus-nursed musculus preferred odor of heterospecific females. Wagneri-nursed spicilegus and spicilegus-nursed wagneri did not demonstrate significant choice of con - or heterospecific female odor. The level of MRI signal obtained from the evaluation of manganese accumulation in AOB neurons was significantly higher when the odor of conspecific estrus females was exposed, compared to urine exposure of heterospecific females. The response pattern changed to the opposite in males raised by heterospecific females. Response patterns of neuronal activity in the MOB to con- and heterospecific female odors were different in cross-fostered and control males. CONCLUSION The maternal environment, including odor, had a greater effect on the level of MRI signal in the AOB than the genetic relationships of the recipient and the donor of the odor stimulus. Behavioral and neuronal responses to con- and heterospecific odors changed in closely related Mus taxa as a result of early experience. We demonstrated the importance of early learning in mate choice in adulthood in mice and the possibility of epigenetic contribution in the formation of precopulatory reproductive isolation.
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Affiliation(s)
- Elena Kotenkova
- Severtsov Institute of Ecology and Evolution RAS, Leninsky Prospect, 33, 119071, Moscow, Russia.
| | - Alex Romachenko
- Institute of Cytology and Genetics SB RAS, Prospekt Lavrentyeva 10, 630090, Novosibirsk, Russia
| | - Alexander Ambaryan
- Severtsov Institute of Ecology and Evolution RAS, Leninsky Prospect, 33, 119071, Moscow, Russia
| | - Aleksei Maltsev
- Severtsov Institute of Ecology and Evolution RAS, Leninsky Prospect, 33, 119071, Moscow, Russia
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24
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Androuin A, Abada YS, Ly M, Santin M, Petiet A, Epelbaum S, Bertrand A, Delatour B. Activity-induced MEMRI cannot detect functional brain anomalies in the APPxPS1-Ki mouse model of Alzheimer's disease. Sci Rep 2019; 9:1140. [PMID: 30718666 PMCID: PMC6361936 DOI: 10.1038/s41598-018-37980-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 12/10/2018] [Indexed: 12/02/2022] Open
Abstract
Alzheimer’s disease (AD) is the most common cause of dementia. Aside neuropathological lesions, abnormal neuronal activity and brain metabolism are part of the core symptoms of the disease. Activity-induced Manganese-Enhanced Magnetic Resonance Imaging (MEMRI) has been proposed as a powerful approach to visualize evoked brain activity in rodents. Here, we evaluated the relevance of MEMRI in measuring neuronal (dys-)function in the APPxPS1 knocked-in (KI) mouse model of AD. Brain anomalies were firstly demonstrated in APPxPS1-Ki mice using cognitive testing (memory impairment) and histological mapping of immediate early gene products (decreased density of fos-positive neurons). Paradoxically, MEMRI analyses were not able to confirm the occurrence of neuronal hypoactivities in vivo. We then performed a neuropathological analysis that highlighted an abnormal increased permeability of the blood-brain barrier (BBB) in APPxPS1-Ki mice. We hypothesized that diffuse weakening of the BBB results in an uncontrolled diffusion of the MR contrast agent and a lack of correlation between manganese accumulation and neuronal activity. These results bring to light a limitation of the activity-induced MEMRI approach when applied to the APPxPS1-Ki mouse model as well as other mouse models harboring a compromised BBB.
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Affiliation(s)
- Alexandre Androuin
- Institut du Cerveau et de la Moelle épinière, INSERM U1127, CNRS UMR7225, Université Pierre et Marie Curie, Sorbonne Universités, Paris, France
| | - Yah-Se Abada
- Institut du Cerveau et de la Moelle épinière, INSERM U1127, CNRS UMR7225, Université Pierre et Marie Curie, Sorbonne Universités, Paris, France
| | - Myriam Ly
- Institut du Cerveau et de la Moelle épinière, INSERM U1127, CNRS UMR7225, Université Pierre et Marie Curie, Sorbonne Universités, Paris, France.,Institut Roche, Boulogne-Billancourt, France
| | - Mathieu Santin
- Institut du Cerveau et de la Moelle épinière, INSERM U1127, CNRS UMR7225, Université Pierre et Marie Curie, Sorbonne Universités, Paris, France.,Center for Neuroimaging Research, Institut du Cerveau et de la Moelle épinière, Paris, France
| | - Alexandra Petiet
- Institut du Cerveau et de la Moelle épinière, INSERM U1127, CNRS UMR7225, Université Pierre et Marie Curie, Sorbonne Universités, Paris, France.,Center for Neuroimaging Research, Institut du Cerveau et de la Moelle épinière, Paris, France
| | - Stéphane Epelbaum
- Institut du Cerveau et de la Moelle épinière, INSERM U1127, CNRS UMR7225, Université Pierre et Marie Curie, Sorbonne Universités, Paris, France.,Centre des Maladies Cognitives et Comportementales, Sorbonne Universités, Hôpital de la Salpêtrière, Paris, France.,Aramis Project Team, Inria Research Center of Paris, Paris, France
| | - Anne Bertrand
- Institut du Cerveau et de la Moelle épinière, INSERM U1127, CNRS UMR7225, Université Pierre et Marie Curie, Sorbonne Universités, Paris, France.,Aramis Project Team, Inria Research Center of Paris, Paris, France
| | - Benoît Delatour
- Institut du Cerveau et de la Moelle épinière, INSERM U1127, CNRS UMR7225, Université Pierre et Marie Curie, Sorbonne Universités, Paris, France.
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25
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Romashchenko AV, Kireeva РЕ, Sharapova MВ, Zapara ТA, Ratushnyak AS. Learning-induced sensory plasticity of mouse olfactory epithelium. Vavilovskii Zhurnal Genet Selektsii 2019. [DOI: 10.18699/vj18.452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Traditionally, studies of the neurobiology of learning and memory focus on the circuitry that interfaces between sensory inputs and behavioral outputs, such as the amygdala and cerebellum. However, evidence is accumulating that some forms of learning can in fact drive stimulusspecifc changes very early in sensory systems, including not only primary sensory cortices but also precortical structures and even the peripheral sensory organs themselves. In this study, we investigated the effect of olfactory associative training on the functional activity of olfactory epithelium neurons in response to an indifferent stimulus (orange oil). It was found that such a peripheral structure of the olfactory system of adult mice as the olfactory epithelium (OE) demonstrates experiencedependent plasticity. In our experiment, associative learning led to changes in the patterns of OE cell activation in response to orange oil in comparison with the control group and animals that were given odor without reinforcement. To interpret the results obtained, we compared the distribution of MRI contrast across the zones of OE in response to a conditioned odor in trained animals and in control animals that were given orange oil at three concentrations: original (used for conditioning), 4fold higher and 4fold lower. Since the OE activation patterns obtained coincided in the group of trained animals and controls, which were stimulated with orange oil at the 4fold higher concentration, it can be concluded that associative conditioning increased the sensitivity of the OE to the conditioned stimulus. The observed increase in OE response to orange oil may be the result of neurogenesis, i. e. the maturation of new olfactory neurons responsive to this stimulus, or the consequence of an increase in individual sensitivity of each OE neuron. Based on data of MRI contrast accumulation in mouse OE, the sensory plasticity way in learninginduced increase in sensitivity of OE to conditioned stimulus is more possible. Thus, the sensory plasticity of the OE plays a signifcant role in the formation of the neuronal response to the provision of an initially indifferent odor and is part of the adaptive responses to the environmental changing.
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Affiliation(s)
- A. V. Romashchenko
- Institute of Computational Technologies, SB RAS; Institute of Cytology and Genetics, SB RAS
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26
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Cloyd RA, Koren SA, Abisambra JF. Manganese-Enhanced Magnetic Resonance Imaging: Overview and Central Nervous System Applications With a Focus on Neurodegeneration. Front Aging Neurosci 2018; 10:403. [PMID: 30618710 PMCID: PMC6300587 DOI: 10.3389/fnagi.2018.00403] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2018] [Accepted: 11/23/2018] [Indexed: 12/16/2022] Open
Abstract
Manganese-enhanced magnetic resonance imaging (MEMRI) rose to prominence in the 1990s as a sensitive approach to high contrast imaging. Following the discovery of manganese conductance through calcium-permeable channels, MEMRI applications expanded to include functional imaging in the central nervous system (CNS) and other body systems. MEMRI has since been employed in the investigation of physiology in many animal models and in humans. Here, we review historical perspectives that follow the evolution of applied MRI research into MEMRI with particular focus on its potential toxicity. Furthermore, we discuss the more current in vivo investigative uses of MEMRI in CNS investigations and the brief but decorated clinical usage of chelated manganese compound mangafodipir in humans.
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Affiliation(s)
- Ryan A Cloyd
- Department of Physiology, University of Kentucky, Lexington, KY, United States.,College of Medicine, University of Kentucky, Lexington, KY, United States.,Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, United States
| | - Shon A Koren
- Department of Physiology, University of Kentucky, Lexington, KY, United States.,Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, United States.,Department of Neuroscience & Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL, United States
| | - Jose F Abisambra
- Department of Physiology, University of Kentucky, Lexington, KY, United States.,Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, United States.,Department of Neuroscience & Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL, United States.,Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, KY, United States
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27
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Almeida-Corrêa S, Czisch M, Wotjak CT. In Vivo Visualization of Active Polysynaptic Circuits With Longitudinal Manganese-Enhanced MRI (MEMRI). Front Neural Circuits 2018; 12:42. [PMID: 29887796 PMCID: PMC5981681 DOI: 10.3389/fncir.2018.00042] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 04/30/2018] [Indexed: 12/23/2022] Open
Abstract
Manganese-enhanced magnetic resonance imaging (MEMRI) is a powerful tool for in vivo non-invasive whole-brain mapping of neuronal activity. Mn2+ enters active neurons via voltage-gated calcium channels and increases local contrast in T1-weighted images. Given the property of Mn2+ of axonal transport, this technique can also be used for tract tracing after local administration of the contrast agent. However, MEMRI is still not widely employed in basic research due to the lack of a complete description of the Mn2+ dynamics in the brain. Here, we sought to investigate how the activity state of neurons modulates interneuronal Mn2+ transport. To this end, we injected mice with low dose MnCl2 2. (i.p., 20 mg/kg; repeatedly for 8 days) followed by two MEMRI scans at an interval of 1 week without further MnCl2 injections. We assessed changes in T1 contrast intensity before (scan 1) and after (scan 2) partial sensory deprivation (unilateral whisker trimming), while keeping the animals in a sensory enriched environment. After correcting for the general decay in Mn2+ content, whole brain analysis revealed a single cluster with higher signal in scan 1 compared to scan 2: the left barrel cortex corresponding to the right untrimmed whiskers. In the inverse contrast (scan 2 > scan 1), a number of brain structures, including many efferents of the left barrel cortex were observed. These results suggest that continuous neuronal activity elicited by ongoing sensory stimulation accelerates Mn2+ transport from the uptake site to its projection terminals, while the blockage of sensory-input and the resulting decrease in neuronal activity attenuates Mn2+ transport. The description of this critical property of Mn2+ dynamics in the brain allows a better understanding of MEMRI functional mechanisms, which will lead to more carefully designed experiments and clearer interpretation of the results.
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Affiliation(s)
- Suellen Almeida-Corrêa
- Department of Stress Neurobiology & Neurogenetics, Max Planck Institute of Psychiatry, Munich, Germany
| | - Michael Czisch
- Core Unit Neuroimaging, Max Planck Institute of Psychiatry, Munich, Germany
| | - Carsten T Wotjak
- Department of Stress Neurobiology & Neurogenetics, Max Planck Institute of Psychiatry, Munich, Germany
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28
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Vousden DA, Cox E, Allemang-Grand R, Laliberté C, Qiu LR, Lindenmaier Z, Nieman BJ, Lerch JP. Continuous manganese delivery via osmotic pumps for manganese-enhanced mouse MRI does not impair spatial learning but leads to skin ulceration. Neuroimage 2018; 173:411-420. [PMID: 29505831 DOI: 10.1016/j.neuroimage.2018.02.046] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 02/22/2018] [Indexed: 12/21/2022] Open
Abstract
Manganese-enhanced magnetic resonance imaging (MEMRI) is a widely used technique in rodent neuroimaging studies. Traditionally, Mn2+ is delivered to animals via a systemic injection; however, this can lead to toxic effects at high doses. Recent studies have shown that subcutaneously implanted mini-osmotic pumps can be used to continuously deliver manganese chloride (MnCl2), and that they produce satisfactory contrast while circumventing many of the toxic side effects. However, neither the time-course of signal enhancement nor the effect of continuous Mn2+ delivery on behaviour, particularly learning and memory, have been well-characterized. Here, we investigated the effect of MnCl2 dose and route of administration on a) spatial learning in the Morris Water Maze and b) tissue signal enhancement in the mouse brain. Even as early as 3 days after pump implantation, infusion of 25-50 mg/kg/day MnCl2 via osmotic pump produced signal enhancement as good as or better than that achieved 24 h after a single 50 mg/kg intraperitoneal injection. Neither route of delivery nor MnCl2 dose adversely affected spatial learning and memory on the water maze. However, especially at higher doses, mice receiving MnCl2 via osmotic pumps developed skin ulceration which limited the imaging window. With these findings, we provide recommendations for route and dose of MnCl2 to use for different study designs.
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Affiliation(s)
- Dulcie A Vousden
- Mouse Imaging Centre, The Hospital for Sick Children, 25 Orde Street, Toronto, ON, M5T 3H7, Canada; Department of Medical Biophysics, University of Toronto, 101 College Street Suite 15-701, Toronto, ON, M5G 1L7, Canada.
| | - Elizabeth Cox
- Mouse Imaging Centre, The Hospital for Sick Children, 25 Orde Street, Toronto, ON, M5T 3H7, Canada
| | - Rylan Allemang-Grand
- Mouse Imaging Centre, The Hospital for Sick Children, 25 Orde Street, Toronto, ON, M5T 3H7, Canada; Department of Medical Biophysics, University of Toronto, 101 College Street Suite 15-701, Toronto, ON, M5G 1L7, Canada
| | - Christine Laliberté
- Mouse Imaging Centre, The Hospital for Sick Children, 25 Orde Street, Toronto, ON, M5T 3H7, Canada
| | - Lily R Qiu
- Mouse Imaging Centre, The Hospital for Sick Children, 25 Orde Street, Toronto, ON, M5T 3H7, Canada; Institute of Medical Science, Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, ON, M5S 1A8, Canada
| | - Zsuzsa Lindenmaier
- Mouse Imaging Centre, The Hospital for Sick Children, 25 Orde Street, Toronto, ON, M5T 3H7, Canada; Department of Medical Biophysics, University of Toronto, 101 College Street Suite 15-701, Toronto, ON, M5G 1L7, Canada
| | - Brian J Nieman
- Mouse Imaging Centre, The Hospital for Sick Children, 25 Orde Street, Toronto, ON, M5T 3H7, Canada; Department of Medical Biophysics, University of Toronto, 101 College Street Suite 15-701, Toronto, ON, M5G 1L7, Canada; Ontario Institute for Cancer Research, MaRS Centre, 661 University Ave, Suite 510, Toronto, ON, M5G 0A3, Canada
| | - Jason P Lerch
- Mouse Imaging Centre, The Hospital for Sick Children, 25 Orde Street, Toronto, ON, M5T 3H7, Canada; Department of Medical Biophysics, University of Toronto, 101 College Street Suite 15-701, Toronto, ON, M5G 1L7, Canada
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29
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Ye Q, Park JE, Gugnani K, Betharia S, Pino-Figueroa A, Kim J. Influence of iron metabolism on manganese transport and toxicity. Metallomics 2017; 9:1028-1046. [PMID: 28620665 DOI: 10.1039/c7mt00079k] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Although manganese (Mn) is critical for the proper functioning of various metabolic enzymes and cofactors, excess Mn in the brain causes neurotoxicity. While the exact transport mechanism of Mn has not been fully understood, several importers and exporters for Mn have been identified over the past decade. In addition to Mn-specific transporters, it has been demonstrated that iron transporters can mediate Mn transport in the brain and peripheral tissues. However, while the expression of iron transporters is regulated by body iron stores, whether or not disorders of iron metabolism modify Mn homeostasis has not been systematically discussed. The present review will provide an update on the role of altered iron status in the transport and toxicity of Mn.
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Affiliation(s)
- Qi Ye
- Department of Pharmaceutical Sciences, Northeastern University, 360 Huntington Avenue 148TF, Boston, MA 02115, USA.
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30
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Bedenk BT, Almeida-Corrêa S, Jurik A, Dedic N, Grünecker B, Genewsky AJ, Kaltwasser SF, Riebe CJ, Deussing JM, Czisch M, Wotjak CT. Mn 2+ dynamics in manganese-enhanced MRI (MEMRI): Ca v1.2 channel-mediated uptake and preferential accumulation in projection terminals. Neuroimage 2017; 169:374-382. [PMID: 29277401 DOI: 10.1016/j.neuroimage.2017.12.054] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 11/27/2017] [Accepted: 12/18/2017] [Indexed: 12/11/2022] Open
Abstract
Manganese-enhanced magnetic resonance imaging (MEMRI) exploits the biophysical similarity of Ca2+ and Mn2+ to map the brain's activity in vivo. However, to what extent different Ca2+ channels contribute to the enhanced signal that MEMRI provides and how Mn2+ dynamics influence Mn2+ brain accumulation after systemic administration of MnCl2 are not yet fully understood. Here, we demonstrate that mice lacking the L-type Ca2+ channel 1.2 (Cav1.2) in the CNS show approximately 50% less increase in MEMRI contrast after repeated systemic MnCl2 injections, as compared to control mice. In contrast, genetic deletion of L-type Ca2+ channel 1.3 (Cav1.3) did not reduce signal. Brain structure- or cell type-specific deletion of Cav1.2 in combination with voxel-wise MEMRI analysis revealed a preferential accumulation of Mn2+ in projection terminals, which was confirmed by local MnCl2 administration to defined brain areas. Taken together, we provide unequivocal evidence that Cav1.2 represents an important channel for neuronal Mn2+ influx after systemic injections. We also show that after neuronal uptake, Mn2+ preferentially accumulates in projection terminals.
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Affiliation(s)
- Benedikt T Bedenk
- Max Planck Institute of Psychiatry, Dept. Stress Neurobiology & Neurogenetics, Kraepelinstr. 2-10, 80804 Munich, Germany; Max Planck Institute of Psychiatry, Core Unit Neuroimaging, Kraepelinstr. 2-10, 80804 Munich, Germany
| | - Suellen Almeida-Corrêa
- Max Planck Institute of Psychiatry, Dept. Stress Neurobiology & Neurogenetics, Kraepelinstr. 2-10, 80804 Munich, Germany
| | - Angela Jurik
- Max Planck Institute of Psychiatry, Dept. Stress Neurobiology & Neurogenetics, Kraepelinstr. 2-10, 80804 Munich, Germany
| | - Nina Dedic
- Max Planck Institute of Psychiatry, Dept. Stress Neurobiology & Neurogenetics, Kraepelinstr. 2-10, 80804 Munich, Germany
| | - Barbara Grünecker
- Max Planck Institute of Psychiatry, Core Unit Neuroimaging, Kraepelinstr. 2-10, 80804 Munich, Germany
| | - Andreas J Genewsky
- Max Planck Institute of Psychiatry, Dept. Stress Neurobiology & Neurogenetics, Kraepelinstr. 2-10, 80804 Munich, Germany
| | - Sebastian F Kaltwasser
- Max Planck Institute of Psychiatry, Dept. Stress Neurobiology & Neurogenetics, Kraepelinstr. 2-10, 80804 Munich, Germany
| | - Caitlin J Riebe
- Max Planck Institute of Psychiatry, Dept. Stress Neurobiology & Neurogenetics, Kraepelinstr. 2-10, 80804 Munich, Germany
| | - Jan M Deussing
- Max Planck Institute of Psychiatry, Dept. Stress Neurobiology & Neurogenetics, Kraepelinstr. 2-10, 80804 Munich, Germany
| | - Michael Czisch
- Max Planck Institute of Psychiatry, Core Unit Neuroimaging, Kraepelinstr. 2-10, 80804 Munich, Germany
| | - Carsten T Wotjak
- Max Planck Institute of Psychiatry, Dept. Stress Neurobiology & Neurogenetics, Kraepelinstr. 2-10, 80804 Munich, Germany.
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31
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Medina CS, Manifold-Wheeler B, Gonzales A, Bearer EL. Automated Computational Processing of 3-D MR Images of Mouse Brain for Phenotyping of Living Animals. ACTA ACUST UNITED AC 2017; 119:29A.5.1-29A.5.38. [PMID: 28678440 DOI: 10.1002/cpmb.40] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Magnetic resonance (MR) imaging provides a method to obtain anatomical information from the brain in vivo that is not typically available by optical imaging because of this organ's opacity. MR is nondestructive and obtains deep tissue contrast with 100-µm3 voxel resolution or better. Manganese-enhanced MRI (MEMRI) may be used to observe axonal transport and localized neural activity in the living rodent and avian brain. Such enhancement enables researchers to investigate differences in functional circuitry or neuronal activity in images of brains of different animals. Moreover, once MR images of a number of animals are aligned into a single matrix, statistical analysis can be done comparing MR intensities between different multi-animal cohorts comprising individuals from different mouse strains or different transgenic animals, or at different time points after an experimental manipulation. Although preprocessing steps for such comparisons (including skull stripping and alignment) are automated for human imaging, no such automated processing has previously been readily available for mouse or other widely used experimental animals, and most investigators use in-house custom processing. This protocol describes a stepwise method to perform such preprocessing for mouse. © 2017 by John Wiley & Sons, Inc.
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Affiliation(s)
| | | | - Aaron Gonzales
- University of New Mexico Health Sciences Center, Albuquerque, New Mexico
| | - Elaine L Bearer
- University of New Mexico Health Sciences Center, Albuquerque, New Mexico.,Division of Biology, California Institute of Technology, Pasadena, California
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Tang Z, Wang J, Xiao Z, Sun X, Feng X, Tang W, Chen Q, Wu L, Wang R, Zhong Y, Wang W, Luo J. Manganese-enhanced magnetic resonance imaging combined with electrophysiology in the evaluation of visual pathway in experimental rat models with monocular blindness. Brain Behav 2017; 7:e00731. [PMID: 28729937 PMCID: PMC5516605 DOI: 10.1002/brb3.731] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 04/15/2017] [Accepted: 04/17/2017] [Indexed: 12/12/2022] Open
Abstract
PURPOSE Our study aimed to explore the feasibility of manganese-enhanced magnetic resonance imaging (MEMRI) combined with visual evoked potentials (VEP) and auditory evoked visual cortex responses (AVR) in evaluating for the establishment of visual/auditory compensatory pathways after monocular blindness. MATERIALS AND METHODS A total of 14 healthy neonatal male Sprague-Dawley rats were randomly divided into two groups (n = 7 for Groups A and B). Right optic nerve (ON) transection was performed on the 7 rats of Group A to obtain a monocularly blind model, and the 7 rats of Group B were chosen as the control group. Four months later, 400 mmol MnCl2 was injected into the left eye in both groups via intravitreal injection. The changes in the visual pathways projected from the blind eye and the remaining eye in Group A and the normal eyes in Group B were compared to determine if new visual compensatory pathways were established. Additionally, VEP tests were performed to determine complete blindness, and AVR examinations were performed to help identify the generation of auditory compensatory function. RESULTS The VEP test indicated complete visual loss after ON transection. In the monocularly blind rats, the contrast-to-noise ratio (CNR) of ON, optic tract (OT), lateral geniculate nucleus (LGN), superior colliculus (SC), optic radiation (OR) and visual cortex (VC) of visual pathway projected from the left eye was significantly higher than that of the right pathway (p < .001). Moreover, the CNR of ON, OT, LGN, SC, OR and VC in the visual pathway projected from the left eye of monocularly blind rats was significantly lower than those of normal rats (p < .05). The AVR results revealed that the corresponding bilateral visual cortex in monocularly blind rats did not respond to the auditory stimulus or showed dissimilation with the low frequency. CONCLUSION MEMRI combined with electrophysiology, including VEP and AVR, may be potentially helpful in the evaluation of the possible generation of new visual/auditory compensatory pathways after monocular blindness.
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Affiliation(s)
- Zuohua Tang
- Department of Radiology Eye and ENT Hospital of Shanghai Medical School Fudan University Shanghai China
| | - Jie Wang
- Department of Radiotherapy Eye and ENT Hospital of Shanghai Medical School Fudan University Shanghai China
| | - Zebin Xiao
- Department of Radiology Eye and ENT Hospital of Shanghai Medical School Fudan University Shanghai China
| | - Xinghuai Sun
- State Key Laboratory of Medical Neurobiology Department of Ophthalmology Eye and ENT Hospital of Shanghai Medical School Institutes of Brain Science Fudan University Shanghai China
| | - Xiaoyuan Feng
- Department of Radiology Huashan Hospital of Shanghai Medical School Fudan University Shanghai China
| | - Weijun Tang
- Department of Radiology Huashan Hospital of Shanghai Medical School Fudan University Shanghai China
| | - Qian Chen
- State Key Laboratory of Medical Neurobiology Department of Ophthalmology Eye and ENT Hospital of Shanghai Medical School Institutes of Brain Science Fudan University Shanghai China
| | - Lingjie Wu
- Department of Otolaryngology Eye and ENT Hospital of Shanghai Medical School Fudan University Shanghai China
| | - Rong Wang
- Department of Radiology Eye and ENT Hospital of Shanghai Medical School Fudan University Shanghai China
| | - Yufeng Zhong
- Department of Radiology Eye and ENT Hospital of Shanghai Medical School Fudan University Shanghai China
| | - Wentao Wang
- Central Laboratory Eye and ENT Hospital of Shanghai Medical School Fudan University Shanghai China
| | - Jianfeng Luo
- Health Statistics Shanghai Medical School Fudan University Shanghai China
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Atanasijevic T, Bouraoud N, McGavern DB, Koretsky AP. Transcranial manganese delivery for neuronal tract tracing using MEMRI. Neuroimage 2017; 156:146-154. [PMID: 28506873 DOI: 10.1016/j.neuroimage.2017.05.025] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 04/27/2017] [Accepted: 05/12/2017] [Indexed: 11/17/2022] Open
Abstract
There has been a growing interest in the use of manganese-enhanced MRI (MEMRI) for neuronal tract tracing in mammals, especially in rodents. For this MEMRI application, manganese solutions are usually directly injected into specific brain regions. Recently it was reported that manganese ions can diffuse through intact rat skull. Here the local manganese concentrations in the brain tissue after transcranial manganese application were quantified and the effectiveness of tracing from the area under the skull where delivery occurred was determined. It was established that transcranially applied manganese yields brain tissue enhancement dependent on the location of application on the skull and that manganese that enters the brain transcranially can trace to deeper brain areas.
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Affiliation(s)
- Tatjana Atanasijevic
- Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Nadia Bouraoud
- Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Dorian B McGavern
- Laboratory of Viral Immunology and Intravital Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Alan P Koretsky
- Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA.
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Poplawsky AJ, Fukuda M, Kim SG. Foundations of layer-specific fMRI and investigations of neurophysiological activity in the laminarized neocortex and olfactory bulb of animal models. Neuroimage 2017; 199:718-729. [PMID: 28502845 DOI: 10.1016/j.neuroimage.2017.05.023] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Revised: 05/02/2017] [Accepted: 05/11/2017] [Indexed: 12/25/2022] Open
Abstract
Laminar organization of neuronal circuits is a recurring feature of how the brain processes information. For instance, different layers compartmentalize different cell types, synaptic activities, and have unique intrinsic and extrinsic connections that serve as units for specialized signal processing. Functional MRI is an invaluable tool to investigate laminar processing in the in vivo human brain, but it measures neuronal activity indirectly by way of the hemodynamic response. Therefore, the accuracy of high-resolution laminar fMRI depends on how precisely it can measure localized microvascular changes nearest to the site of evoked activity. To determine the specificity of fMRI responses to the true neurophysiological responses across layers, the flexibility to invasive procedures in animal models has been necessary. In this review, we will examine different fMRI contrasts and their appropriate uses for layer-specific fMRI, and how localized laminar processing was examined in the neocortex and olfactory bulb. Through collective efforts, it was determined that microvessels, including capillaries, are regulated within single layers and that several endogenous and contrast-enhanced fMRI contrast mechanisms can separate these neural-specific vascular changes from the nonspecific, especially cerebral blood volume-weighted fMRI with intravenous contrast agent injection. We will also propose some open questions that are relevant for the successful implementation of layer-specific fMRI and its potential future directions to study laminar processing when combined with optogenetics.
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Affiliation(s)
- Alexander John Poplawsky
- Neuroimaging Laboratory, Department of Radiology, University of Pittsburgh, Pittsburgh, PA, USA.
| | - Mitsuhiro Fukuda
- Neuroimaging Laboratory, Department of Radiology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Seong-Gi Kim
- Center for Neuroscience Imaging Research, Institute of Basic Science, Suwon 440-746, Republic of Korea; Department of Biomedical Engineering, Sungkyunkwan University, Suwon 440-746, Republic of Korea
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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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Tang Z, Wu L, Xiao Z, Feng X, Sun X, Tang W, Wang J, Jin L. Manganese-enhanced MRI (ME MRI) in evaluation of the auditory pathway in an experimental rat model. NMR IN BIOMEDICINE 2017; 30:e3677. [PMID: 27976435 DOI: 10.1002/nbm.3677] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Revised: 11/01/2016] [Accepted: 11/01/2016] [Indexed: 06/06/2023]
Abstract
This study aimed to explore the optimal dose and manner of administration for visualization of the auditory pathway on manganese-enhanced MRI (ME MRI). Twenty-four healthy male Sprague-Dawley rats were randomly divided into three experimental groups (n = 8 for Groups A, B and C). The rats in Groups A, B and C were subjected to MnCl2 injection through the tympanum, inner ear endolymph and perilymph, respectively (0.2 M for four rats and 0.4 M for the others in each group) and observed at 1, 2, 3, 4, 7 and 10 days after the operation with 3.0 T MRI. The signal intensity (SI) and dynamic changes of the auditory pathways at various times, and at two doses through three injection routes, were compared by statistical analysis. Administration of MnCl2 through the perilymph best showed the complete auditory pathway (P < 0.01), whereas administration though the tympanum only demonstrated part of the pathway. The SI was highest at 24 h after administration of the tracer and began to decline at 48 h. The SI of the auditory cortex was higher after the injection of 0.4 M MnCl2 than that of 0.2 M MnCl2 . ME MRI best demonstrated the whole auditory pathway at 24 h after the injection of 0.4 M MnCl2 through the perilymph in the rat, which provided an optimal method for the study of ME MRI of the auditory pathway in the animal model.
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Affiliation(s)
- Zuohua Tang
- Department of Radiology, Eye and ENT Hospital of Shanghai Medical School, Fudan University, Shanghai, China
| | - Lingjie Wu
- Department of Otolaryngology, Eye and ENT Hospital of Shanghai Medical School, Fudan University, Shanghai, China
| | - Zebin Xiao
- Department of Radiology, Eye and ENT Hospital of Shanghai Medical School, Fudan University, Shanghai, China
| | - Xiaoyuan Feng
- Department of Radiology, Huashan Hospital of Shanghai Medical School, Fudan University, Shanghai, China
| | - Xinghuai Sun
- Department of Ophthalmology, Eye and ENT Hospital of Shanghai Medical School, State Key Laboratory of Medical Neurobiology, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Weijun Tang
- Department of Radiology, Huashan Hospital of Shanghai Medical School, Fudan University, Shanghai, China
| | - Jie Wang
- Department of Radiotherapy, Eye and ENT Hospital of Shanghai Medical School, Fudan University, Shanghai, China
| | - Lixin Jin
- Siemens Ltd. Healthcare Sector, Shanghai, China
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RETRACTED: Exploring the mechanism by which accumbal deep brain stimulation attenuates morphine-induced reinstatement through manganese-enhanced MRI and pharmacological intervention. Exp Neurol 2017; 290:29-40. [PMID: 28038985 DOI: 10.1016/j.expneurol.2016.12.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Revised: 12/21/2016] [Accepted: 12/23/2016] [Indexed: 11/22/2022]
Abstract
This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal).
This article has been retracted at the request of the authors.
The authors have requested to retract this paper as the corresponding author had not sought the prior agreement of his co-authors to submit the paper for publication.
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Martirosyan NL, Turner GH, Kaufman J, Patel AA, Belykh E, Kalani MYS, Theodore N, Preul MC. Manganese-enhanced MRI Offers Correlation with Severity of Spinal Cord Injury in Experimental Models. Open Neuroimag J 2016; 10:139-147. [PMID: 28144384 PMCID: PMC5226969 DOI: 10.2174/1874440001610010139] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Revised: 10/04/2016] [Accepted: 10/16/2016] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Spinal cord injuries (SCI) are clinically challenging, because neural regeneration after cord damage is unknown. In SCI animal models, regeneration is evaluated histologically, requiring animal sacrifice. Noninvasive techniques are needed to detect longitudinal SCI changes. OBJECTIVE To compare manganese-enhanced magnetic resonance imaging (MRI [MEMRI]) in hemisection and transection of SCI rat models with diffusion tensor imaging (DTI) and histology. METHODS Rats underwent T9 spinal cord transection (n=6), hemisection (n=6), or laminectomy without SCI (controls, n=6). One-half of each group received lateral ventricle MnCl2 injections 24 hours later. Conventional DTI or T1-weighted MRI was performed 84 hours post-surgery. MEMRI signal intensity ratio above and below the SCI level was calculated. Fractional anisotropy (FA) measurements were taken 1 cm rostral to the SCI. The percentage of FA change was calculated 10 mm rostral to the SCI epicenter, between FA at the dorsal column lesion normalized to a lateral area without FA change. Myelin load (percentage difference) among groups was analyzed by histology. RESULTS In transection and hemisection groups, mean MEMRI ratios were 0.62 and 0.87, respectively, versus 0.99 in controls (P<0.001 and P<0.001, respectively); mean FA decreases were 67.5% and 40.1%, respectively, compared with a 6.1% increase in controls (P=0.002 and P=0.019, respectively). Mean myelin load decreased by 38.8% (transection) and 51.8% (hemisection) compared to controls (99.1%) (P<0.001 and P<0.001, respectively). Pearson's correlation coefficients were -0.94 for MEMRI ratio and FA changes and 0.87 for MEMRI and myelin load. CONCLUSION MEMERI results correlated to SCI severity measured by FA and myelin load. MEMRI is a useful noninvasive tool to assess neuronal damage after SCI.
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Affiliation(s)
- Nikolay L Martirosyan
- Departments of Neurosurgery, Barrow Neurological Institute St. Joseph's Hospital and Medical Center Phoenix, Arizona,USA
| | - Gregory H Turner
- Center for Preclinical Imaging, Barrow Neurological Institute St. Joseph's Hospital and Medical Center Phoenix, Arizona, USA
| | - Jason Kaufman
- Department of Anatomy, Midwestern University Glendale, Arizona, USA
| | - Arpan A Patel
- Departments of Neurosurgery, Barrow Neurological Institute St. Joseph's Hospital and Medical Center Phoenix, Arizona,USA
| | - Evgenii Belykh
- Departments of Neurosurgery, Barrow Neurological Institute St. Joseph's Hospital and Medical Center Phoenix, Arizona,USA ; Irkutsk Scientific Center of Surgery and Traumatology, Irkutsk, Russia
| | - M Yashar S Kalani
- Departments of Neurosurgery, Barrow Neurological Institute St. Joseph's Hospital and Medical Center Phoenix, Arizona,USA
| | - Nicholas Theodore
- Departments of Neurosurgery, Barrow Neurological Institute St. Joseph's Hospital and Medical Center Phoenix, Arizona,USA
| | - Mark C Preul
- Departments of Neurosurgery, Barrow Neurological Institute St. Joseph's Hospital and Medical Center Phoenix, Arizona,USA
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Ulyanova A, To XV, Asad ABMA, Han W, Chuang KH. MEMRI detects neuronal activity and connectivity in hypothalamic neural circuit responding to leptin. Neuroimage 2016; 147:904-915. [PMID: 27729278 DOI: 10.1016/j.neuroimage.2016.10.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Revised: 10/03/2016] [Accepted: 10/07/2016] [Indexed: 10/20/2022] Open
Abstract
Hypothalamus plays the central role in regulating energy homeostasis. To understand the hypothalamic neurocircuit in responding to leptin, Manganese-Enhanced MRI (MEMRI) was applied. Highly elevated signal could be mapped in major nuclei of the leptin signaling pathway, including the arcuate nucleus (ARC), paraventricular nucleus (PVN), ventromedial hypothalamus (VMH) and dorsomedial hypothalamus (DMH) in fasted mice and the enhancement was reduced by leptin administration. However, whether changes in MEMRI signal reflect Ca2+ channel activity, neuronal activation or connectivity in the leptin signaling pathway are not clear. By blocking L-type Ca2+ channels, the signal enhancement in the ARC, PVN and DMH, but not VMH, was reduced. By disrupting microtubule with colchicine, signal enhancement of the secondary neural areas like DMH and PVN was delayed which is consistent with the known projection density from ARC into these regions. Finally, strong correlation between c-fos expression and MEMRI signal increase rate was observed in the ARC, VMH and DMH. Together, we provide experimental evidence that MEMRI signal could represent activity and connectivity in certain hypothalamic nuclei and hence may be used for mapping activated neuronal pathway in vivo. This understanding would facilitate the application of MEMRI for evaluation of hypothalamic dysfunction in metabolic diseases.
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Affiliation(s)
- Anna Ulyanova
- Magnetic Resonance Imaging Group, Singapore Bioimaging Consortium, Agency for Science Technology and Research (A⁎STAR), Singapore; Department of Physiology, National University of Singapore, Singapore
| | - Xuan Vinh To
- Magnetic Resonance Imaging Group, Singapore Bioimaging Consortium, Agency for Science Technology and Research (A⁎STAR), Singapore
| | - A B M A Asad
- Magnetic Resonance Imaging Group, Singapore Bioimaging Consortium, Agency for Science Technology and Research (A⁎STAR), Singapore
| | - Weiping Han
- Lab of Metabolic Medicine, Singapore Bioimaging Consortium, A⁎STAR, Singapore
| | - Kai-Hsiang Chuang
- Magnetic Resonance Imaging Group, Singapore Bioimaging Consortium, Agency for Science Technology and Research (A⁎STAR), Singapore; Department of Physiology, National University of Singapore, Singapore.
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Wang WL, Xu H, Li Y, Ma ZZ, Sun XD, Hu YT. Dose response and time course of manganese-enhanced magnetic resonance imaging for visual pathway tracing in vivo. Neural Regen Res 2016; 11:1185-90. [PMID: 27630707 PMCID: PMC4994466 DOI: 10.4103/1673-5374.187065] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Axonal tracing is useful for detecting optic nerve injury and regeneration, but many commonly used methods cannot be used to observe axoplasmic flow and synaptic transmission in vivo. Manganese (Mn(2+))-enhanced magnetic resonance imaging (MEMRI) can be used for in vivo longitudinal tracing of the visual pathway. Here, we explored the dose response and time course of an intravitreal injection of MnCl2 for tracing the visual pathway in rabbits in vivo using MEMRI. We found that 2 mM MnCl2 enhanced images of the optic nerve but not the lateral geniculate body or superior colliculus, whereas at all other doses tested (5-40 mM), images of the visual pathway from the retina to the contralateral superior colliculus were significantly enhanced. The images were brightest at 24 hours, and then decreased in brightness until the end of the experiment (7 days). No signal enhancement was observed in the visual cortex at any concentration of MnCl2. These results suggest that MEMRI is a viable method for temporospatial tracing of the visual pathway in vivo. Signal enhancement in MEMRI depends on the dose of MnCl2, and the strongest signals appear 24 hours after intravitreal injection.
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Affiliation(s)
- Wei-Ling Wang
- Department of Ophthalmology, Beijing Tsinghua Changgung Hospital, Tsinghua University Medical Center, Beijing, China; Department of Ophthalmology, General Hospital of Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous Region, China
| | - Hui Xu
- Department of Radiology, Peking University Third Hospital, Beijing, China
| | - Ying Li
- Peking University Eye Center, Peking University Third Hospital, Key Laboratory of Vision Loss and Restoration, Ministry of Education, Beijing, China
| | - Zhi-Zhong Ma
- Peking University Eye Center, Peking University Third Hospital, Key Laboratory of Vision Loss and Restoration, Ministry of Education, Beijing, China
| | - Xiao-Dong Sun
- Department of Ophthalmology, Shanghai Jiao Tong University Affiliated First People's Hospital, Shanghai, China
| | - Yun-Tao Hu
- Department of Ophthalmology, Beijing Tsinghua Changgung Hospital, Tsinghua University Medical Center, Beijing, China; Peking University Eye Center, Peking University Third Hospital, Key Laboratory of Vision Loss and Restoration, Ministry of Education, Beijing, China
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Neuroimaging in Alzheimer's disease: preclinical challenges toward clinical efficacy. Transl Res 2016; 175:37-53. [PMID: 27033146 DOI: 10.1016/j.trsl.2016.03.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 03/05/2016] [Accepted: 03/06/2016] [Indexed: 12/21/2022]
Abstract
The scope of this review focuses on recent applications in preclinical and clinical magnetic resonance imaging (MRI) toward accomplishing the goals of early detection and responses to therapy in animal models of Alzheimer's disease (AD). Driven by the outstanding efforts of the Alzheimer's Disease Neuroimaging Initiative (ADNI), a truly invaluable resource, the initial use of MRI in AD imaging has been to assess changes in brain anatomy, specifically assessing brain shrinkage and regional changes in white matter tractography using diffusion tensor imaging. However, advances in MRI have led to multiple efforts toward imaging amyloid beta plaques first without and then with the use of MRI contrast agents. These technological advancements have met with limited success and are not yet appropriate for the clinic. Recent developments in molecular imaging inclusive of high-power liposomal-based MRI contrast agents as well as fluorine 19 ((19)F) MRI and manganese enhanced MRI have begun to propel promising advances toward not only plaque imaging but also using MRI to detect perturbations in subcellular processes occurring within the neuron. This review concludes with a discussion about the necessity for the development of novel preclinical models of AD that better recapitulate human AD for the imaging to truly be meaningful and for substantive progress to be made toward understanding and effectively treating AD. Furthermore, the continued support of outstanding programs such as ADNI as well as the development of novel molecular imaging agents and MRI fast scanning sequences will also be requisite to effectively translate preclinical findings to the clinic.
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Olson KE, Bade AN, Schutt CR, Dong J, Shandler SJ, Boska MD, Mosley RL, Gendelman HE, Liu Y. Manganese-Enhanced Magnetic Resonance Imaging for Detection of Vasoactive Intestinal Peptide Receptor 2 Agonist Therapy in a Model of Parkinson's Disease. Neurotherapeutics 2016; 13:635-46. [PMID: 27329163 PMCID: PMC4965412 DOI: 10.1007/s13311-016-0449-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Neuroprotective immunity is defined by transformation of T-cell polarity for therapeutic gain. For neurodegenerative disorders and specifically for Parkinson's disease (PD), granulocyte-macrophage colony stimulating factor or vasoactive intestinal peptide receptor 2 (VIPR2) agonists elicit robust anti-inflammatory microglial responses leading to neuronal sparing in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-intoxicated mice. While neurotherapeutic potential was demonstrated for PD, there remain inherent limitations in translating these inventions from the laboratory to patients. One obstacle in translating such novel neurotherapeutics centers on the availability of suitable noninvasive methods to track disease progression and therapeutic efficacy. To this end, we developed manganese-enhanced magnetic resonance imaging (MEMRI) assays as a way to track a linkage between glial activation and VIPR2 agonist (LBT-3627)-induced neuroprotective immunity for MPTP-induced nigrostriatal degeneration. Notably, LBT-3627-treated, MPTP-intoxicated mice show reduced MEMRI brain signal intensities. These changes paralleled reduced astrogliosis and resulted in sparing of nigral tyrosine hydroxylase neurons. Most importantly, the data suggest that MEMRI can be developed as a biomarker tool to monitor neurotherapeutic responses that are relevant to common neurodegenerative disorders used to improve disease outcomes.
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Affiliation(s)
- Katherine E Olson
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE, USA
| | - Aditya N Bade
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE, USA
| | - Charles R Schutt
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE, USA
| | - Jingdong Dong
- Department of Radiology, University of Nebraska Medical Center, Omaha, NE, USA
| | | | - Michael D Boska
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE, USA
- Department of Radiology, University of Nebraska Medical Center, Omaha, NE, USA
| | - R Lee Mosley
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE, USA
| | - Howard E Gendelman
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE, USA.
| | - Yutong Liu
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE, USA
- Department of Radiology, University of Nebraska Medical Center, Omaha, NE, USA
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Semiquantitative assessment of optic nerve injury using manganese-enhanced MRI. Jpn J Radiol 2016; 34:356-65. [PMID: 26943911 DOI: 10.1007/s11604-016-0533-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2015] [Accepted: 02/22/2016] [Indexed: 10/22/2022]
Abstract
OBJECTIVE To evaluate the capability of manganese (Mn(2+))-enhanced MRI (MEMRI) in a continuously semiquantitative assessment of rat optic nerve (ON) injury. METHODS Forty rats were divided into three groups: (I) a control group that was submitted to MEMRI or to fluorescent labeling of retinal ganglion cells (RGCs) (n = 10); (II) an ON injury group that was submitted to MEMRI (n = 15); (III) an ON injury group that was submitted to fluorescent labeling of RGCs (n = 15). Groups II and III were examined at 3, 7, and 14 days post-lesion (dpl), when the contrast-to-noise ratio (CNR) of the retina and ON was measured on MEMRI images and the RGCs were counted by fluorescence microscopy and compared between the groups. RESULTS In the control group, the intact visual pathway from the retina to the contralateral superior colliculus was visualized by MEMRI. In group II, continuous Mn(2+) enhancement was seen from the retina to the lesion site of the optic nerves at 3, 7, and 14 dpl. However, no Mn(2+) enhancement was observed distal to the lesion site at those time points. The observed Mn(2+) enhancement proximal to the ON lesion site declined between 7 and 14 dpl. The decrease in Mn(2+)-enhanced signal intensity at these sites at 7 and 14 dpl when compared to that at 3 dpl was significant (P < 0.05). The RGC density dropped by 6.84, 45.31, and 72.36 % at 3, 7, and 14 dpl, respectively. CONCLUSION MEMRI can be used to evaluate the structural changes after optic nerve injury.
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Modulation of nucleus accumbens connectivity by alcohol drinking and naltrexone in alcohol-preferring rats: A manganese-enhanced magnetic resonance imaging study. Eur Neuropsychopharmacol 2016; 26:445-55. [PMID: 26851200 DOI: 10.1016/j.euroneuro.2016.01.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Revised: 12/31/2015] [Accepted: 01/15/2016] [Indexed: 11/23/2022]
Abstract
The nonselective opioid receptor antagonist naltrexone is now used for the treatment of alcoholism, yet naltrexone's central mechanism of action remains poorly understood. One line of evidence suggests that opioid antagonists regulate alcohol drinking through interaction with the mesolimbic dopamine system. Hence, our goal here was to examine the role of the nucleus accumbens connectivity in alcohol reinforcement and naltrexone's actions using manganese-enhanced magnetic resonance imaging (MEMRI). Following long-term free-choice drinking of alcohol and water, AA (Alko Alcohol) rats received injections of MnCl2 into the nucleus accumbens for activity-dependent tracing of accumbal connections. Immediately after the accumbal injections, rats were imaged using MEMRI, and then allowed to drink either alcohol or water for the next 24h. Naltrexone was administered prior to the active dark period, and the second MEMRI was performed 24h after the first scan. Comparison of signal intensity at 1 and 24h after accumbal MnCl2 injections revealed an ipsilateral continuum through the ventral pallidum, bed nucleus of the stria terminalis, globus pallidus, and lateral hypothalamus to the substantia nigra and ventral tegmental area. Activation was also seen in the rostral part of the insular cortex and regions of the prefrontal cortex. Alcohol drinking resulted in enhanced activation of these connections, whereas naltrexone suppressed alcohol-induced activity. These data support the involvement of the accumbal connections in alcohol reinforcement and mediation of naltrexone's suppressive effects on alcohol drinking through their deactivation.
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Manganese-enhanced MR imaging of brain activation evoked by noxious peripheral electrical stimulation. Neurosci Lett 2015; 613:13-8. [PMID: 26733299 DOI: 10.1016/j.neulet.2015.11.027] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Revised: 10/26/2015] [Accepted: 11/17/2015] [Indexed: 11/21/2022]
Abstract
As imaging technology develops, magnetic resonance imaging (MRI) has furthered our understanding of brain function by clarifying the anatomical structure and generating functional imaging data related to information processing in pain conditions. Recent studies have reported that manganese (Mn(2+))-enhanced MRI (MEMRI) provides valuable information about the functions of the central nervous system. The aim of this study was to identify specific brain regions activated during noxious electric stimulation using high-resolution MEMRI. Male Sprague Dawley rats were divided into three groups: naïve, sham electrical stimulation, and noxious electric stimulation. Under urethane with α-chloralose mixture anesthesia, a catheter was placed in the external carotid artery to administrate 20% mannitol and manganese chloride (25mM MnCl2). Noxious electric stimulation (2Hz, 10V) was applied to the hind paw with a needle electrode. Stimulation-induced neuronal activation was detected using 4.7-T MRI. In response to noxious electrical stimulation, remarkable Mn(2+)-enhanced signals were observed in the agranular insular cortex, auditory cortex, primary somatosensory cortex of the hind limb, and granular and dysgranular insular cortex, which correspond to sensory tactile electric stimulus to the hindpaws. These results indicate that the combination of MEMRI with activity-induced Mn(2+)-dependent contrast can delineate functional areas in the rat brain.
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Bone Marrow-Derived Cells as a Therapeutic Approach to Optic Nerve Diseases. Stem Cells Int 2015; 2016:5078619. [PMID: 26649049 PMCID: PMC4663341 DOI: 10.1155/2016/5078619] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2015] [Accepted: 09/10/2015] [Indexed: 12/16/2022] Open
Abstract
Following optic nerve injury associated with acute or progressive diseases, retinal ganglion cells (RGCs) of adult mammals degenerate and undergo apoptosis. These diseases have limited therapeutic options, due to the low inherent capacity of RGCs to regenerate and due to the inhibitory milieu of the central nervous system. Among the numerous treatment approaches investigated to stimulate neuronal survival and axonal extension, cell transplantation emerges as a promising option. This review focuses on cell therapies with bone marrow mononuclear cells and bone marrow-derived mesenchymal stem cells, which have shown positive therapeutic effects in animal models of optic neuropathies. Different aspects of available preclinical studies are analyzed, including cell distribution, potential doses, routes of administration, and mechanisms of action. Finally, published and ongoing clinical trials are summarized.
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Demain B, Davoust C, Plas B, Bolan F, Boulanouar K, Renaud L, Darmana R, Vaysse L, Vieu C, Loubinoux I. Corticospinal Tract Tracing in the Marmoset with a Clinical Whole-Body 3T Scanner Using Manganese-Enhanced MRI. PLoS One 2015; 10:e0138308. [PMID: 26398500 PMCID: PMC4580626 DOI: 10.1371/journal.pone.0138308] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Accepted: 08/28/2015] [Indexed: 11/18/2022] Open
Abstract
Manganese-enhanced MRI (MEMRI) has been described as a powerful tool to depict the architecture of neuronal circuits. In this study we investigated the potential use of in vivo MRI detection of manganese for tracing neuronal projections from the primary motor cortex (M1) in healthy marmosets (Callithrix Jacchus). We determined the optimal dose of manganese chloride (MnCl2) among 800, 400, 40 and 8 nmol that led to manganese-induced hyperintensity furthest from the injection site, as specific to the corticospinal tract as possible, and that would not induce motor deficit. A commonly available 3T human clinical MRI scanner and human knee coil were used to follow hyperintensity in the corticospinal tract 24h after injection. A statistical parametric map of seven marmosets injected with the chosen dose, 8 nmol, showed the corticospinal tract and M1 connectivity with the basal ganglia, substantia nigra and thalamus. Safety was determined for the lowest dose that did not induce dexterity and grip strength deficit, and no behavioral effects could be seen in marmosets who received multiple injections of manganese one month apart. In conclusion, our study shows for the first time in marmosets, a reliable and reproducible way to perform longitudinal ME-MRI experiments to observe the integrity of the marmoset corticospinal tract on a clinical 3T MRI scanner.
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Affiliation(s)
- Boris Demain
- Inserm, Imagerie cérébrale et handicaps neurologiques, UMR 825, F-31024, Toulouse, France
- Université de Toulouse, UPS, Imagerie cérébrale et handicaps neurologiques, UMR 825, CHU Purpan, Place du Dr Baylac, F-31059, Toulouse, Cedex 9, France
- CNRS-LAAS, 7 avenue du colonel Roche, F-31077, Toulouse, France
| | - Carole Davoust
- Inserm, Imagerie cérébrale et handicaps neurologiques, UMR 825, F-31024, Toulouse, France
- Université de Toulouse, UPS, Imagerie cérébrale et handicaps neurologiques, UMR 825, CHU Purpan, Place du Dr Baylac, F-31059, Toulouse, Cedex 9, France
| | - Benjamin Plas
- Inserm, Imagerie cérébrale et handicaps neurologiques, UMR 825, F-31024, Toulouse, France
- Université de Toulouse, UPS, Imagerie cérébrale et handicaps neurologiques, UMR 825, CHU Purpan, Place du Dr Baylac, F-31059, Toulouse, Cedex 9, France
- Pôle Neurosciences, Centre Hospitalier Universitaire de Toulouse, Toulouse, France
| | - Faye Bolan
- Inserm, Imagerie cérébrale et handicaps neurologiques, UMR 825, F-31024, Toulouse, France
- Université de Toulouse, UPS, Imagerie cérébrale et handicaps neurologiques, UMR 825, CHU Purpan, Place du Dr Baylac, F-31059, Toulouse, Cedex 9, France
| | - Kader Boulanouar
- Inserm, Imagerie cérébrale et handicaps neurologiques, UMR 825, F-31024, Toulouse, France
- Université de Toulouse, UPS, Imagerie cérébrale et handicaps neurologiques, UMR 825, CHU Purpan, Place du Dr Baylac, F-31059, Toulouse, Cedex 9, France
| | - Luc Renaud
- CNRS, Centre de Recherche Cerveau & Cognition, UMR 5549, F-31024, Toulouse, France
| | - Robert Darmana
- Inserm, Imagerie cérébrale et handicaps neurologiques, UMR 825, F-31024, Toulouse, France
- Université de Toulouse, UPS, Imagerie cérébrale et handicaps neurologiques, UMR 825, CHU Purpan, Place du Dr Baylac, F-31059, Toulouse, Cedex 9, France
| | - Laurence Vaysse
- Inserm, Imagerie cérébrale et handicaps neurologiques, UMR 825, F-31024, Toulouse, France
- Université de Toulouse, UPS, Imagerie cérébrale et handicaps neurologiques, UMR 825, CHU Purpan, Place du Dr Baylac, F-31059, Toulouse, Cedex 9, France
| | - Christophe Vieu
- CNRS-LAAS, 7 avenue du colonel Roche, F-31077, Toulouse, France
| | - Isabelle Loubinoux
- Inserm, Imagerie cérébrale et handicaps neurologiques, UMR 825, F-31024, Toulouse, France
- Université de Toulouse, UPS, Imagerie cérébrale et handicaps neurologiques, UMR 825, CHU Purpan, Place du Dr Baylac, F-31059, Toulouse, Cedex 9, France
- * E-mail:
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Schur RM, Sheng L, Sahu B, Yu G, Gao S, Yu X, Maeda A, Palczewski K, Lu ZR. Manganese-Enhanced MRI for Preclinical Evaluation of Retinal Degeneration Treatments. Invest Ophthalmol Vis Sci 2015. [PMID: 26225634 DOI: 10.1167/iovs.15-16522] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
PURPOSE Apply manganese-enhanced magnetic resonance imaging (MEMRI) to assess ion channel activity and structure of retinas from mice subject to light-induced retinal degeneration treated with prophylactic agents. METHODS Abca4(-/-)Rdh8(-/-) double knockout mice with and without prophylactic retinylamine (Ret-NH2) treatment were illuminated with strong light. Manganese-enhanced MRI was used to image the retina 2 hours after intravitreous injection of MnCl2 into one eye. Contrast-enhanced MRIs of the retina and vitreous humor in each experimental group were assessed and correlated with the treatment. Findings were compared with standard structural and functional assessments of the retina by optical coherence tomography (OCT), histology, and electroretinography (ERG). RESULTS Manganese-enhanced MRI contrast in the retina was high in nonilluminated and illuminated Ret-NH2-treated mice, whereas no enhancement was evident in the retina of the light-illuminated mice without Ret-NH2 treatment (P < 0.0005). A relatively high signal enhancement was also observed in the vitreous humor of mice treated with Ret-NH2. Strong MEMRI signal enhancement in the retinas of mice treated with retinylamine was correlated with their structural integrity and function evidenced by OCT, histology, and a strong ERG light response. CONCLUSIONS Manganese-enhanced MRI has the potential to assess the response of the retina to prophylactic treatment based on the measurement of ion channel activity. This approach could be used as a complementary tool in preclinical development of new prophylactic therapies for retinopathies.
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Affiliation(s)
- Rebecca M Schur
- Department of Biomedical Engineering School of Engineering, Case Western Reserve University, Cleveland, Ohio, United States
| | - Li Sheng
- Department of Biomedical Engineering School of Engineering, Case Western Reserve University, Cleveland, Ohio, United States
| | - Bhubanananda Sahu
- Department of Ophthalmology and Visual Sciences, School of Medicine, Case Western Reserve University, Cleveland, Ohio, United States
| | - Guanping Yu
- Department of Biomedical Engineering School of Engineering, Case Western Reserve University, Cleveland, Ohio, United States
| | - Songqi Gao
- Department of Pharmacology, School of Medicine, Case Western Reserve University, Cleveland, Ohio, United States
| | - Xin Yu
- Department of Biomedical Engineering School of Engineering, Case Western Reserve University, Cleveland, Ohio, United States
| | - Akiko Maeda
- Department of Ophthalmology and Visual Sciences, School of Medicine, Case Western Reserve University, Cleveland, Ohio, United States 3Department of Pharmacology, School of Medicine, Case Western Reserve University, Cleveland, Ohio, United States
| | - Krzysztof Palczewski
- Department of Pharmacology, School of Medicine, Case Western Reserve University, Cleveland, Ohio, United States
| | - Zheng-Rong Lu
- Department of Biomedical Engineering School of Engineering, Case Western Reserve University, Cleveland, Ohio, United States
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Zhao DW, Zhang LT, Cheng HY, Zhang YL, Min JY, Xiao HL, Wang Y. Monitoring dynamic alterations in calcium homeostasis by T1-mapping manganese-enhanced MRI (MEMRI) in the early stage of small intestinal ischemia-reperfusion injury. NMR IN BIOMEDICINE 2015; 28:958-966. [PMID: 26086648 DOI: 10.1002/nbm.3335] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Revised: 05/01/2015] [Accepted: 05/06/2015] [Indexed: 06/04/2023]
Abstract
Manganese-enhanced MRI studies have proven to be useful in monitoring physiological activities associated with calcium ions (Ca(2+)) due to the paramagnetic property of the manganese ion (Mn(2+)), which makes it an excellent probe of Ca(2+) . In this study, we developed a method in which a Mn(2+)-enhanced T1 -map MRI could enable the monitoring of Ca(2+) influx during the early stages of intestinal ischemia-reperfusion (I/R) injury. The Mn(2+) infusion protocol was optimized by obtaining dose-dependent and time-course wash-out curves using a Mn(2+)-enhanced T1-map MRI of rabbit abdomens following an intravenous infusion of 50 mmol/l MnCl2 (5-10 nmol/g body weight (BW)). In the rabbit model of intestinal I/R injury, T1 values were derived from the T1 maps in the intestinal wall region and revealed a relationship between the dose of the infused MnCl2 and the intestinal wall relaxation time. Significant Mn(2+) clearance was also observed over time in control animals after the infusion of Mn(2+) at a dose of 10 nmol/g BW. This technique was also shown to be sensitive enough to monitor variations in calcium ion homeostasis in vivo after small intestinal I/R injury. The T1 values of the intestinal I/R group were significantly lower (P < 0.05) than that of the control group at 5, 10, and 15 min after Mn(2+) infusion. Our data suggest that MnCl2 has the potential to be an MRI contrast agent that can be effectively used to monitor changes in intracellular Ca(2+) homeostasis during the early stages of intestinal I/R injury.
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Affiliation(s)
- Da-wei Zhao
- Department of Radiology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing, China
| | - Le-tian Zhang
- Department of Radiology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing, China
| | - Hai-yun Cheng
- Department of Radiology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing, China
| | - Yu-long Zhang
- Department of Radiology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing, China
| | - Jia-yan Min
- Department of Radiology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing, China
| | - Hua-liang Xiao
- Department of Pathology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing, China
| | - Yi Wang
- Department of Radiology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing, China
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Malheiros JM, Paiva FF, Longo BM, Hamani C, Covolan L. Manganese-Enhanced MRI: Biological Applications in Neuroscience. Front Neurol 2015. [PMID: 26217304 PMCID: PMC4498388 DOI: 10.3389/fneur.2015.00161] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Magnetic resonance imaging (MRI) is an excellent non-invasive tool to investigate biological systems. The administration of the paramagnetic divalent ion manganese (Mn2+) enhances MRI contrast in vivo. Due to similarities between Mn2+ and calcium (Ca2+), the premise of manganese-enhanced MRI (MEMRI) is that the former may enter neurons and other excitable cells through voltage-gated Ca2+ channels. As such, MEMRI has been used to trace neuronal pathways, define morphological boundaries, and study connectivity in morphological and functional imaging studies. In this article, we provide a brief overview of MEMRI and discuss recently published data to illustrate the usefulness of this method, particularly in animal models.
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Affiliation(s)
- Jackeline Moraes Malheiros
- Department of Physiology, Universidade Federal de São Paulo - UNIFESP , São Paulo , Brazil ; Centro de Imagens e Espectroscopia In vivo por Ressonância Magnética, Institute of Physics of São Carlos, Universidade de São Paulo , São Carlos , Brazil
| | - Fernando Fernandes Paiva
- Centro de Imagens e Espectroscopia In vivo por Ressonância Magnética, Institute of Physics of São Carlos, Universidade de São Paulo , São Carlos , Brazil
| | - Beatriz Monteiro Longo
- Department of Physiology, Universidade Federal de São Paulo - UNIFESP , São Paulo , Brazil
| | - Clement Hamani
- Department of Physiology, Universidade Federal de São Paulo - UNIFESP , São Paulo , Brazil ; Research Imaging Centre, Centre for Addiction and Mental Health , Toronto, ON , Canada ; Centre for Addiction and Mental Health, Campbell Family Mental Health Research Institute , Toronto, ON , Canada
| | - Luciene Covolan
- Department of Physiology, Universidade Federal de São Paulo - UNIFESP , São Paulo , Brazil
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