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Taylor M, Cheng AB, Hodkinson DJ, Afacan O, Zurakowski D, Bajic D. Body size and brain volumetry in the rat following prolonged morphine administration in infancy and adulthood. FRONTIERS IN PAIN RESEARCH 2023; 4:962783. [PMID: 36923651 PMCID: PMC10008895 DOI: 10.3389/fpain.2023.962783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Accepted: 01/20/2023] [Indexed: 02/28/2023] Open
Abstract
Background Prolonged morphine treatment in infancy is associated with a high incidence of opioid tolerance and dependence, but our knowledge of the long-term consequences of this treatment is sparse. Using a rodent model, we examined the (1) short- and (2) long-term effects of prolonged morphine administration in infancy on body weight and brain volume, and (3) we evaluated if subsequent dosing in adulthood poses an increased brain vulnerability. Methods Newborn rats received subcutaneous injections of either morphine or equal volume of saline twice daily for the first two weeks of life. In adulthood, animals received an additional two weeks of saline or morphine injections before undergoing structural brain MRI. After completion of treatment, structural T2-weigthed MRI images were acquired on a 7 T preclinical scanner (Bruker) using a RARE FSE sequence. Total and regional brain volumes were manually extracted from the MRI images using ITK-SNAP (v.3.6). Regions of interest included the brainstem, the cerebellum, as well as the forebrain and its components: the cerebral cortex, hippocampus, and deep gray matter (including basal ganglia, thalamus, hypothalamus, ventral tegmental area). Absolute (cm3) and normalized (as % total brain volume) values were compared using a one-way ANOVA with Tukey HSD post-hoc test. Results Prolonged morphine administration in infancy was associated with lower body weight and globally smaller brain volumes, which was not different between the sexes. In adulthood, females had lower body weights than males, but no difference was observed in brain volumes between treatment groups. Our results are suggestive of no long-term effect of prolonged morphine treatment in infancy with respect to body weight and brain size in either sex. Interestingly, prolonged morphine administration in adulthood was associated with smaller brain volumes that differed by sex only in case of previous exposure to morphine in infancy. Specifically, we report significantly smaller total brain volume of female rats on account of decreased volumes of forebrain and cortex. Conclusions Our study provides insight into the short- and long-term consequences of prolonged morphine administration in an infant rat model and suggests brain vulnerability to subsequent exposure in adulthood that might differ with sex.
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Affiliation(s)
- Milo Taylor
- Department of Anesthesiology, Critical Care and Pain Medicine, Boston Children’s Hospital, Boston, MA, United States
- Harvard College, Massachusetts Hall, Cambridge, MA, United States
| | - Anya Brooke Cheng
- Department of Anesthesiology, Critical Care and Pain Medicine, Boston Children’s Hospital, Boston, MA, United States
- Harvard College, Massachusetts Hall, Cambridge, MA, United States
| | - Duncan Jack Hodkinson
- Division of Clinical Neuroscience, School of Medicine, University of Nottingham, Nottingham, United Kingdom
- Sir Peter Mansfield Imaging Centre, School of Medicine, University of Nottingham, Nottingham, United Kingdom
- National Institute for Health Research (NIHR), Nottingham Biomedical Research Center, Queens Medical Center, Nottingham, United Kingdom
- Versus Arthritis Pain Centre, University of Nottingham, Nottingham, United Kingdom
| | - Onur Afacan
- Department of Radiology, Boston Children’s Hospital, Boston, MA, United States
- Harvard Medical School, Boston, MA, United States
| | - David Zurakowski
- Department of Anesthesiology, Critical Care and Pain Medicine, Boston Children’s Hospital, Boston, MA, United States
- Harvard Medical School, Boston, MA, United States
| | - Dusica Bajic
- Department of Anesthesiology, Critical Care and Pain Medicine, Boston Children’s Hospital, Boston, MA, United States
- Harvard Medical School, Boston, MA, United States
- Correspondence: Dusica Bajic
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The brainstem connectome database. Sci Data 2022; 9:168. [PMID: 35414055 PMCID: PMC9005652 DOI: 10.1038/s41597-022-01219-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 02/25/2022] [Indexed: 11/29/2022] Open
Abstract
Connectivity data of the nervous system and subdivisions, such as the brainstem, cerebral cortex and subcortical nuclei, are necessary to understand connectional structures, predict effects of connectional disorders and simulate network dynamics. For that purpose, a database was built and analyzed which comprises all known directed and weighted connections within the rat brainstem. A longterm metastudy of original research publications describing tract tracing results form the foundation of the brainstem connectome (BC) database which can be analyzed directly in the framework neuroVIISAS. The BC database can be accessed directly by connectivity tables, a web-based tool and the framework. Analysis of global and local network properties, a motif analysis, and a community analysis of the brainstem connectome provides insight into its network organization. For example, we found that BC is a scale-free network with a small-world connectivity. The Louvain modularity and weighted stochastic block matching resulted in partially matching of functions and connectivity. BC modeling was performed to demonstrate signal propagation through the somatosensory pathway which is affected in Multiple sclerosis. Measurement(s) | brainstem | Technology Type(s) | tract tracing metastudy | Factor Type(s) | brain region | Sample Characteristic - Organism | Rattus rattus | Sample Characteristic - Environment | Experimental setup | Sample Characteristic - Location | Germany |
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Liu J, Chen Y, Stephens R, Cornea E, Goldman B, Gilmore JH, Gao W. Hippocampal functional connectivity development during the first two years indexes 4-year working memory performance. Cortex 2021; 138:165-177. [PMID: 33691225 PMCID: PMC8058274 DOI: 10.1016/j.cortex.2021.02.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 11/03/2020] [Accepted: 02/05/2021] [Indexed: 02/08/2023]
Abstract
The hippocampus is a key limbic region involved in higher-order cognitive processes including learning and memory. Although both typical and atypical functional connectivity patterns of the hippocampus have been well-studied in adults, the developmental trajectory of hippocampal connectivity during infancy and how it relates to later working memory performance remains to be elucidated. Here we used resting state fMRI (rsfMRI) during natural sleep to examine the longitudinal development of hippocampal functional connectivity using a large cohort (N = 202) of infants at 3 weeks (neonate), 1 year, and 2 years of age. Next, we used multivariate modeling to investigate the relationship between both cross-sectional and longitudinal growth in hippocampal connectivity and 4-year working memory outcome. Results showed robust local functional connectivity of the hippocampus in neonates with nearby limbic and subcortical regions, with dramatic maturation and increasing connectivity with key default mode network (DMN) regions resulting in adult-like topology of the hippocampal functional connectivity by the end of the first year. This pattern was stabilized and further consolidated by 2 years of age. Importantly, cross-sectional and longitudinal measures of hippocampal connectivity in the first year predicted subsequent behavioral measures of working memory at 4 years of age. Taken together, our findings provide insight into the development of hippocampal functional circuits underlying working memory during this early critical period.
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Affiliation(s)
- Janelle Liu
- Biomedical Imaging Research Institute, Department of Biomedical Sciences, and Imaging, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
| | - Yuanyuan Chen
- Biomedical Imaging Research Institute, Department of Biomedical Sciences, and Imaging, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
| | - Rebecca Stephens
- Department of Psychiatry, University of North Carolina Chapel Hill, Chapel Hill, NC, USA.
| | - Emil Cornea
- Department of Psychiatry, University of North Carolina Chapel Hill, Chapel Hill, NC, USA.
| | - Barbara Goldman
- FPG Child Development Institute and Department of Psychology & Neuroscience, University of North Carolina Chapel Hill, Chapel Hill, NC, USA.
| | - John H Gilmore
- Department of Psychiatry, University of North Carolina Chapel Hill, Chapel Hill, NC, USA.
| | - Wei Gao
- Biomedical Imaging Research Institute, Department of Biomedical Sciences, and Imaging, Cedars-Sinai Medical Center, Los Angeles, CA, USA; David Geffen School of Medicine, University of California, Los Angeles, CA, USA.
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López-Gutiérrez MF, Gracia-Tabuenca Z, Ortiz JJ, Camacho FJ, Young LJ, Paredes RG, Díaz NF, Portillo W, Alcauter S. Brain functional networks associated with social bonding in monogamous voles. eLife 2021; 10:e55081. [PMID: 33443015 PMCID: PMC7847304 DOI: 10.7554/elife.55081] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2020] [Accepted: 01/11/2021] [Indexed: 12/30/2022] Open
Abstract
Previous studies have related pair-bonding in Microtus ochrogaster, the prairie vole, with plastic changes in several brain regions. However, the interactions between these socially relevant regions have yet to be described. In this study, we used resting-state magnetic resonance imaging to explore bonding behaviors and functional connectivity of brain regions previously associated with pair-bonding. Thirty-two male and female prairie voles were scanned at baseline, 24 hr, and 2 weeks after the onset of cohabitation. By using network-based statistics, we identified that the functional connectivity of a corticostriatal network predicted the onset of affiliative behavior, while another predicted the amount of social interaction during a partner preference test. Furthermore, a network with significant changes in time was revealed, also showing associations with the level of partner preference. Overall, our findings revealed the association between network-level functional connectivity changes and social bonding.
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Affiliation(s)
| | - Zeus Gracia-Tabuenca
- Instituto de Neurobiología, Universidad Nacional Autónoma de MéxicoQuerétaroMexico
| | - Juan J Ortiz
- Instituto de Neurobiología, Universidad Nacional Autónoma de MéxicoQuerétaroMexico
| | - Francisco J Camacho
- Instituto de Neurobiología, Universidad Nacional Autónoma de MéxicoQuerétaroMexico
| | - Larry J Young
- Silvio O Conte Center for Oxytocin and Social Cognition, Center for Translational Social Neuroscience, Yerkes National Primate Research Center, Department of Psychiatry and Behavioral Sciences, Emory UniversityAtlantaUnited States
| | - Raúl G Paredes
- Instituto de Neurobiología, Universidad Nacional Autónoma de MéxicoQuerétaroMexico
- Escuela Nacional de Estudios Superiores, Unidad Juriquilla, Universidad Nacional Autónoma de MéxicoQuerétaroMexico
| | - Néstor F Díaz
- Instituto Nacional de Perinatología Isidro Espinosa de los ReyesCiudad de MéxicoMexico
| | - Wendy Portillo
- Instituto de Neurobiología, Universidad Nacional Autónoma de MéxicoQuerétaroMexico
| | - Sarael Alcauter
- Instituto de Neurobiología, Universidad Nacional Autónoma de MéxicoQuerétaroMexico
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Kim MJ, Yum MS, Jo Y, Lee M, Kim EJ, Shim WH, Ko TS. Delayed Functional Networks Development and Altered Fast Oscillation Dynamics in a Rat Model of Cortical Malformation. Front Neurosci 2020; 14:711. [PMID: 32973422 PMCID: PMC7461924 DOI: 10.3389/fnins.2020.00711] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 06/12/2020] [Indexed: 11/13/2022] Open
Abstract
Malformations of cortical development (MCD) is associated with a wide range of developmental delay and drug resistant epilepsy in children. By using resting-state functional magnetic resonance imaging (RS-fMRI) and event-related spectral perturbation (ERSP) of cortical electroencephalography (EEG) data, we tried to investigate the neural changes of spatiotemporal functional connectivity (FC) and fast oscillation (FO) dynamics in a rat model of methylazoxymethanol (MAM)-induced MCD. A total of 28 infant rats with prenatal exposure to MAM and those of age matched 28 controls with prenatal saline exposure were used. RS-fMRI were acquired at postnatal day 15 (P15) and 29 (P29), and correlation coefficient analysis of eleven region of interests (ROI) was done to find the differences of functional networks between four groups. Two hour-cortical EEGs were also recorded at P15 and P29 and the ERSP of gamma (30–80 Hz) and ripples (80–200 Hz) were analyzed. The rats with MCD showed significantly delayed development of superior colliculus-brainstem network compared to control rats at P15. In contrast to marked maturation of default mode network (DMN) in controls from P15 to P29, there was no clear development in MCD rats. The MCD rats showed significantly higher cortical gamma and ripples-ERSP at P15 and lower cortical ripples-ERSP at P29 than those of control rats. This study demonstrated delayed development of FC and altered cortical FO dynamics in rats with malformed brain. The results should be further investigated in terms of the epileptogenesis and cognitive dysfunction in patients with MCD.
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Affiliation(s)
- Min-Jee Kim
- Department of Pediatrics, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, South Korea
| | - Mi-Sun Yum
- Department of Pediatrics, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, South Korea
| | - Youngheun Jo
- Department of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea
| | - Minyoung Lee
- Department of Pediatrics, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, South Korea
| | - Eun-Jin Kim
- Department of Pediatrics, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, South Korea
| | - Woo-Hyun Shim
- Department of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea
| | - Tae-Sung Ko
- Department of Pediatrics, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, South Korea
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Validation of Chronic Restraint Stress Model in Young Adult Rats for the Study of Depression Using Longitudinal Multimodal MR Imaging. eNeuro 2020; 7:ENEURO.0113-20.2020. [PMID: 32669346 PMCID: PMC7396811 DOI: 10.1523/eneuro.0113-20.2020] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 06/15/2020] [Accepted: 07/03/2020] [Indexed: 12/25/2022] Open
Abstract
Prior research suggests that the neurobiological underpinnings of depression include aberrant brain functional connectivity, neurometabolite levels, and hippocampal volume. Chronic restraint stress (CRS) depression model in rats has been shown to elicit behavioral, gene expression, protein, functional connectivity, and hippocampal volume changes similar to those in human depression. However, no study to date has examined the association between behavioral changes and brain changes within the same animals. This study specifically addressed the correlation between the outcomes of behavioral tests and multiple 9.4 T magnetic resonance imaging (MRI) modalities in the CRS model using data collected longitudinally in the same animals. CRS involved placing young adult male Sprague Dawley rats in individual transparent tubes for 2.5 h daily over 13 d. Elevated plus maze (EPM) and forced swim tests (FSTs) confirmed the presence of anxiety-like and depression-like behaviors, respectively, postrestraint. Resting-state functional MRI (rs-fMRI) data revealed hypoconnectivity within the salience and interoceptive networks and hyperconnectivity of several brain regions to the cingulate cortex. Proton magnetic resonance spectroscopy revealed decreased sensorimotor cortical glutamate (Glu), glutamine (Gln), and combined Glu-Gln (Glx) levels. Volumetric analysis of T2-weighted images revealed decreased hippocampal volume. Importantly, these changes parallel those found in human depression, suggesting that the CRS rodent model has utility for translational studies and novel intervention development for depression.
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An analytical workflow for seed-based correlation and independent component analysis in interventional resting-state fMRI studies. Neurosci Res 2020; 165:26-37. [PMID: 32464181 DOI: 10.1016/j.neures.2020.05.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 05/08/2020] [Accepted: 05/18/2020] [Indexed: 12/12/2022]
Abstract
Resting-state functional MRI (rs-fMRI) is a task-free method of detecting spatially distinct brain regions with correlated activity, which form organised networks known as resting-state networks (RSNs). The two most widely used methods for analysing RSN connectivity are seed-based correlation analysis (SCA) and independent component analysis (ICA) but there is no established workflow of the optimal combination of analytical steps and how to execute them. Rodent rs-fMRI data from our previous longitudinal brain stimulation studies were used to investigate these two methods using FSL. Specifically, we examined: (1) RSN identification and group comparisons in ICA, (2) ICA-based denoising compared to nuisance signal regression in SCA, and (3) seed selection in SCA. In ICA, using a baseline-only template resulted in greater functional connectivity within RSNs and more sensitive detection of group differences than when an average pre/post stimulation template was used. In SCA, the use of an ICA-based denoising method in the preprocessing of rs-fMRI data and the use of seeds from individual functional connectivity maps in running group comparisons increased the sensitivity of detecting group differences by preventing the reduction in signals of interest. Accordingly, when analysing animal and human rs-fMRI data, we infer that the use of baseline-only templates in ICA and ICA-based denoising and individualised seeds in SCA will improve the reliability of results and comparability across rs-fMRI studies.
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Schwanke S, Jenssen J, Eipert P, Schmitt O. Towards Differential Connectomics with NeuroVIISAS. Neuroinformatics 2019; 17:163-179. [PMID: 30014279 DOI: 10.1007/s12021-018-9389-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The comparison of connectomes is an essential step to identify changes in structural and functional neuronal networks. However, the connectomes themselves as well as the comparisons of connectomes could be manifold. In most applications, comparisons of connectomes are applied to specific sets of data. In many studies collections of scripts are applied optimized for certain species (non-generic approaches) or diseases (control versus disease group connectomes). These collections of scripts have a limited functionality which do not support functional and topographic mappings of connectomes (hemispherical asymmetries, peripheral nervous system). The platform-independent and generic neuroVIISAS framework is built to circumvent limitations that come with variants of nomenclatures, connectivity lists and connectional hierarchies as well as restrictions to structural connectome analyses. A new analytical module is introduced into the framework to compare different types of connectomes and different representations of the same connectome within a unique software environment. As an example a differential analysis of the partial connectome of the laboratory rat that is based on virus tract tracing with the same regions of non-virus tract tracing has been performed. A relatively large connectional coherence between the two different techniques was found. However, some detected connections are described by virus tract-tracing only.
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Affiliation(s)
- Sebastian Schwanke
- Department of Anatomy, University of Rostock, Gertrudenstr. 9, 18057, Rostock, Germany
| | - Jörg Jenssen
- Department of Anatomy, University of Rostock, Gertrudenstr. 9, 18057, Rostock, Germany
| | - Peter Eipert
- Department of Anatomy, University of Rostock, Gertrudenstr. 9, 18057, Rostock, Germany
| | - Oliver Schmitt
- Department of Anatomy, University of Rostock, Gertrudenstr. 9, 18057, Rostock, Germany.
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Tudela R, Muñoz-Moreno E, Sala-Llonch R, López-Gil X, Soria G. Resting State Networks in the TgF344-AD Rat Model of Alzheimer's Disease Are Altered From Early Stages. Front Aging Neurosci 2019; 11:213. [PMID: 31440158 PMCID: PMC6694297 DOI: 10.3389/fnagi.2019.00213] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 07/26/2019] [Indexed: 12/12/2022] Open
Abstract
A better and non-invasive characterization of the preclinical phases of Alzheimer's disease (AD) is important to advance its diagnosis and obtain more effective benefits from potential treatments. The TgF344-AD rat model has been well characterized and shows molecular, behavioral and brain connectivity alterations that resemble the silent period of the pathology. Our aim was to longitudinally investigate functional brain connectivity in established resting-state networks (RSNs) obtained by independent component analysis (ICA) in a cohort of TgF344-AD and control rats every 3 months, from 5 to 18 months of age, to cover different stages of the disease. Before each acquisition, working memory performance was evaluated by the delayed non match-to-sample (DNMS) task. Differences in the temporal evolution were observed between groups in the amplitude and shape of the somatosensorial and sensorimotor networks but not in the whole default mode network (DMN). Subsequent high dimensional ICA analysis showed early alterations in the anterior DMN subnetwork activity of TgF344-AD rats compared to controls. Performance of DNMS task was positively correlated with somatosensorial network at 5 months of age in the wild-type (WT) animals but not in the Tg-F344 rats. At different time points, DMN showed negative correlation with cognitive performance in the control group while in the transgenic group the correlation was positive. In addition, behavioral differences observed at 5 months of age correlated with alterations in the posterior DMN subnetwork. We have demonstrated that functional connectivity using ICA represents a useful biomarker also in animal models of AD such as the TgF344AD rats, as it allows the identification of alterations associated with the progression of the disease, detecting differences in specific networks even at very early stages.
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Affiliation(s)
- Raúl Tudela
- Consorcio Centro de Investigación Biomédica en Red (CIBER) de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Group of Biomedical Imaging, University of Barcelona, Barcelona, Spain
| | - Emma Muñoz-Moreno
- Experimental 7T MRI Unit, Institut d’Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS), Barcelona, Spain
| | - Roser Sala-Llonch
- Department of Biomedicine, Faculty of Medicine, University of Barcelona, Barcelona, Spain
| | - Xavier López-Gil
- Experimental 7T MRI Unit, Institut d’Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS), Barcelona, Spain
| | - Guadalupe Soria
- Consorcio Centro de Investigación Biomédica en Red (CIBER) de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Group of Biomedical Imaging, University of Barcelona, Barcelona, Spain
- Experimental 7T MRI Unit, Institut d’Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS), Barcelona, Spain
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Frequency-specific effects of low-intensity rTMS can persist for up to 2 weeks post-stimulation: A longitudinal rs-fMRI/MRS study in rats. Brain Stimul 2019; 12:1526-1536. [PMID: 31296402 DOI: 10.1016/j.brs.2019.06.028] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 06/23/2019] [Accepted: 06/26/2019] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Evidence suggests that repetitive transcranial magnetic stimulation (rTMS), a non-invasive neuromodulation technique, alters resting brain activity. Despite anecdotal evidence that rTMS effects wear off, there are no reports of longitudinal studies, even in humans, mapping the therapeutic duration of rTMS effects. OBJECTIVE Here, we investigated the longitudinal effects of repeated low-intensity rTMS (LI-rTMS) on healthy rodent resting-state networks (RSNs) using resting-state functional MRI (rs-fMRI) and on sensorimotor cortical neurometabolite levels using proton magnetic resonance spectroscopy (MRS). METHODS Sprague-Dawley rats received 10 min LI-rTMS daily for 15 days (10 Hz or 1 Hz stimulation, n = 9 per group). MRI data were acquired at baseline, after seven days and after 14 days of daily stimulation and at two more timepoints up to three weeks post-cessation of daily stimulation. RESULTS 10 Hz stimulation increased RSN connectivity and GABA, glutamine, and glutamate levels. 1 Hz stimulation had opposite but subtler effects, resulting in decreased RSN connectivity and glutamine levels. The induced changes decreased to baseline levels within seven days following stimulation cessation in the 10 Hz group but were sustained for at least 14 days in the 1 Hz group. CONCLUSION Overall, our study provides evidence of long-term frequency-specific effects of LI-rTMS. Additionally, the transient connectivity changes following 10 Hz stimulation suggest that current treatment protocols involving this frequency may require ongoing "top-up" stimulation sessions to maintain therapeutic effects.
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Johnson FK, Delpech JC, Thompson GJ, Wei L, Hao J, Herman P, Hyder F, Kaffman A. Amygdala hyper-connectivity in a mouse model of unpredictable early life stress. Transl Psychiatry 2018; 8:49. [PMID: 29463821 PMCID: PMC5820270 DOI: 10.1038/s41398-018-0092-z] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Revised: 12/06/2017] [Accepted: 12/13/2017] [Indexed: 01/09/2023] Open
Abstract
Childhood maltreatment is associated with a wide range of psychopathologies including anxiety that emerge in childhood and in many cases persist in adulthood. Increased amygdala activation in response to threat and abnormal amygdala connectivity with frontolimbic brain regions, such as the hippocampus and the prefrontal cortex, are some of the most consistent findings seen in individuals exposed to childhood maltreatment. The underlying mechanisms responsible for these changes are difficult to study in humans but can be elucidated using animal models of early-life stress. Such studies are especially powerful in the mouse where precise control of the genetic background and the stress paradigm can be coupled with resting-state fMRI (rsfMRI) to map abnormal connectivity in circuits that regulate anxiety. To address this issue we first compared the effects of two models of early-life stress, limited bedding (LB) and unpredictable postnatal stress (UPS), on anxiety-like behavior in juvenile and adult mice. We found that UPS, but not LB, causes a robust increase in anxiety in juvenile and adult male mice. Next, we used rsfMRI to compare frontolimbic connectivity in control and UPS adult male mice. We found increased amygdala-prefrontal cortex and amygdala-hippocampus connectivity in UPS. The strength of the amygdala-hippocampal and amygdala-prefrontal cortex connectivity was highly correlated with anxiety-like behavior in the open-field test and elevated plus maze. These findings are the first to link hyperconnectivity in frontolimbic circuits and increased anxiety in a mouse model of early-life stress, allowing for more mechanistic understanding of parallel findings in humans.
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Affiliation(s)
- Frances K Johnson
- Department of Psychiatry, Yale University School of Medicine, 300 George Street, Suite 901, New Haven, CT, 06511, USA
| | - Jean-Christophe Delpech
- Department of Psychiatry, Yale University School of Medicine, 300 George Street, Suite 901, New Haven, CT, 06511, USA
- Department of Newborn Medicine, Boston Children's Hospital, Harvard medical school, Boston, MA, 02115, USA
| | - Garth J Thompson
- Department of Radiology & Biomedical Imaging and Magnetic Resonance Research Center, Yale University, New Haven, CT, 06520, USA
- iHuman Institute, ShanghaiTech University, 393 Middle Huaxia Road, Ren Building, Room B204, Zhangjiang, Pudong, Shanghai, 201210, China
| | - Lan Wei
- Department of Psychiatry, Yale University School of Medicine, 300 George Street, Suite 901, New Haven, CT, 06511, USA
| | - Jin Hao
- Department of Psychiatry, Yale University School of Medicine, 300 George Street, Suite 901, New Haven, CT, 06511, USA
| | - Peter Herman
- Department of Radiology & Biomedical Imaging and Magnetic Resonance Research Center, Yale University, New Haven, CT, 06520, USA
| | - Fahmeed Hyder
- Department of Radiology & Biomedical Imaging and Magnetic Resonance Research Center, Yale University, New Haven, CT, 06520, USA
- Department of Biomedical Engineering, Yale University, New Haven, CT, 06519, USA
| | - Arie Kaffman
- Department of Psychiatry, Yale University School of Medicine, 300 George Street, Suite 901, New Haven, CT, 06511, USA.
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Bajic D, Craig MM, Mongerson CRL, Borsook D, Becerra L. Identifying Rodent Resting-State Brain Networks with Independent Component Analysis. Front Neurosci 2017; 11:685. [PMID: 29311770 PMCID: PMC5733053 DOI: 10.3389/fnins.2017.00685] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Accepted: 11/22/2017] [Indexed: 01/08/2023] Open
Abstract
Rodent models have opened the door to a better understanding of the neurobiology of brain disorders and increased our ability to evaluate novel treatments. Resting-state functional magnetic resonance imaging (rs-fMRI) allows for in vivo exploration of large-scale brain networks with high spatial resolution. Its application in rodents affords researchers a powerful translational tool to directly assess/explore the effects of various pharmacological, lesion, and/or disease states on known neural circuits within highly controlled settings. Integration of animal and human research at the molecular-, systems-, and behavioral-levels using diverse neuroimaging techniques empowers more robust interrogations of abnormal/ pathological processes, critical for evolving our understanding of neuroscience. We present a comprehensive protocol to evaluate resting-state brain networks using Independent Component Analysis (ICA) in rodent model. Specifically, we begin with a brief review of the physiological basis for rs-fMRI technique and overview of rs-fMRI studies in rodents to date, following which we provide a robust step-by-step approach for rs-fMRI investigation including data collection, computational preprocessing, and brain network analysis. Pipelines are interwoven with underlying theory behind each step and summarized methodological considerations, such as alternative methods available and current consensus in the literature for optimal results. The presented protocol is designed in such a way that investigators without previous knowledge in the field can implement the analysis and obtain viable results that reliably detect significant differences in functional connectivity between experimental groups. Our goal is to empower researchers to implement rs-fMRI in their respective fields by incorporating technical considerations to date into a workable methodological framework.
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Affiliation(s)
- Dusica Bajic
- Department of Anesthesiology, Perioperative and Pain Medicine, Boston Children's Hospital, Boston, MA, United States.,Center for Pain and the Brain, Boston Children's Hospital, Boston, MA, United States.,Department of Anaesthesia, Harvard Medical School, Harvard University, Boston, MA, United States
| | - Michael M Craig
- Department of Anesthesiology, Perioperative and Pain Medicine, Boston Children's Hospital, Boston, MA, United States.,Center for Pain and the Brain, Boston Children's Hospital, Boston, MA, United States
| | - Chandler R L Mongerson
- Department of Anesthesiology, Perioperative and Pain Medicine, Boston Children's Hospital, Boston, MA, United States.,Center for Pain and the Brain, Boston Children's Hospital, Boston, MA, United States
| | - David Borsook
- Department of Anesthesiology, Perioperative and Pain Medicine, Boston Children's Hospital, Boston, MA, United States.,Center for Pain and the Brain, Boston Children's Hospital, Boston, MA, United States.,Department of Anaesthesia, Harvard Medical School, Harvard University, Boston, MA, United States
| | - Lino Becerra
- Department of Anesthesiology, Perioperative and Pain Medicine, Boston Children's Hospital, Boston, MA, United States.,Center for Pain and the Brain, Boston Children's Hospital, Boston, MA, United States.,Department of Anaesthesia, Harvard Medical School, Harvard University, Boston, MA, United States
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