1
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Wang C, Samantzis M, Balbi M. Protocol to measure monosynaptic connections between different cortical regions in mice using cell-pair cross correlogram of spike events. STAR Protoc 2024; 5:103035. [PMID: 38678571 PMCID: PMC11068920 DOI: 10.1016/j.xpro.2024.103035] [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: 01/02/2024] [Revised: 02/29/2024] [Accepted: 04/10/2024] [Indexed: 05/01/2024] Open
Abstract
Neuromodulation can facilitate interactions between neurons to rescue impaired brain function after stroke. Here, we present a protocol for measuring putative monosynaptic connections between different cortical regions. We detail procedures for tetrode fabrication, implantation surgery, stroke induction in mice, multi-site in vivo electrophysiological recording, units clustering, principal neuron/interneuron classification, and functional connection analysis. This protocol allows us to understand the mechanisms of stroke recovery. For complete details on the use and execution of this protocol, please refer to Wang et al.1.
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Affiliation(s)
- Cong Wang
- Engineering Research Center of Traditional Chinese Medicine Intelligent Rehabilitation, Ministry of Education, Shanghai 201203, China; Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Montana Samantzis
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Matilde Balbi
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia.
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2
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Franx B, Dijkhuizen RM, Dippel DWJ. Acute Ischemic Stroke in the Clinic and the Laboratory: Targets for Translational Research. Neuroscience 2024:S0306-4522(24)00159-3. [PMID: 38670254 DOI: 10.1016/j.neuroscience.2024.04.006] [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: 01/03/2024] [Revised: 03/26/2024] [Accepted: 04/15/2024] [Indexed: 04/28/2024]
Abstract
Ischemic stroke research has enabled significant advancements in diagnosis, treatment, and management of this debilitating disease, yet challenges remain standing in the way of better patient prognoses. In this narrative review, a fictional case illustrates challenges and uncertainties that medical professionals still face - penumbra identification, lack of neuroprotective agents, side-effects of tissue plasminogen activator, dearth of molecular biomarkers, incomplete microvascular reperfusion or no-reflow, post-recanalization hyperperfusion, blood pressure management and procedural anesthetic effects. The current state of the field is broadly reviewed per topic, with the aim to introduce a broad audience (scientist and clinician alike) to recent successes in translational stroke research and pending scientific queries that are tractable for preclinical assessment. Opportunities for co-operation between clinical and experimental stroke experts are highlighted to increase the size and frequency of strides the field makes to improve our understanding of this disease and ways of treating it.
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Affiliation(s)
- Bart Franx
- Translational Neuroimaging Group, Center for Image Sciences, University Medical Center Utrecht and Utrecht University, Utrecht, the Netherlands
| | - Rick M Dijkhuizen
- Translational Neuroimaging Group, Center for Image Sciences, University Medical Center Utrecht and Utrecht University, Utrecht, the Netherlands
| | - Diederik W J Dippel
- Stroke Center, Dept of Neurology, Erasmus University Medical Center, Rotterdam, the Netherlands.
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3
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Bottom-Tanzer S, Corella S, Meyer J, Sommer M, Bolaños L, Murphy T, Quiñones S, Heiney S, Shtrahman M, Whalen M, Oren R, Higley MJ, Cardin JA, Noubary F, Armbruster M, Dulla C. Traumatic brain injury disrupts state-dependent functional cortical connectivity in a mouse model. Cereb Cortex 2024; 34:bhae038. [PMID: 38365273 DOI: 10.1093/cercor/bhae038] [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: 10/16/2023] [Revised: 01/17/2024] [Accepted: 01/18/2024] [Indexed: 02/18/2024] Open
Abstract
Traumatic brain injury (TBI) is the leading cause of death in young people and can cause cognitive and motor dysfunction and disruptions in functional connectivity between brain regions. In human TBI patients and rodent models of TBI, functional connectivity is decreased after injury. Recovery of connectivity after TBI is associated with improved cognition and memory, suggesting an important link between connectivity and functional outcome. We examined widespread alterations in functional connectivity following TBI using simultaneous widefield mesoscale GCaMP7c calcium imaging and electrocorticography (ECoG) in mice injured using the controlled cortical impact (CCI) model of TBI. Combining CCI with widefield cortical imaging provides us with unprecedented access to characterize network connectivity changes throughout the entire injured cortex over time. Our data demonstrate that CCI profoundly disrupts functional connectivity immediately after injury, followed by partial recovery over 3 weeks. Examining discrete periods of locomotion and stillness reveals that CCI alters functional connectivity and reduces theta power only during periods of behavioral stillness. Together, these findings demonstrate that TBI causes dynamic, behavioral state-dependent changes in functional connectivity and ECoG activity across the cortex.
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Affiliation(s)
- Samantha Bottom-Tanzer
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA 02111, United States
- MD/PhD Program, Tufts University School of Medicine, Boston, MA 02111, United States
- Neuroscience Program, Tufts Graduate School of Biomedical Sciences, Boston, MA 02111, United States
| | - Sofia Corella
- Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States
- MD/PhD Program, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States
| | - Jochen Meyer
- Department of Neurology, Baylor College of Medicine, Houston, TX 77030, United States
| | - Mary Sommer
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA 02111, United States
| | - Luis Bolaños
- Department of Psychiatry, University of British Columbia, Vancouver, British Columbia, V6T 1Z4, Canada
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4
| | - Timothy Murphy
- Department of Psychiatry, University of British Columbia, Vancouver, British Columbia, V6T 1Z4, Canada
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4
| | - Sadi Quiñones
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA 02111, United States
- Neuroscience Program, Tufts Graduate School of Biomedical Sciences, Boston, MA 02111, United States
| | - Shane Heiney
- Iowa Neuroscience Institute, University of Iowa, Iowa City, IA 52242, United States
| | - Matthew Shtrahman
- Department of Neurosciences, University of California San Diego, La Jolla, CA 92093, United States
| | - Michael Whalen
- Department of Pediatrics, Harvard Medical School, Massachusetts General Hospital, Boston, MA 02115, United States
| | - Rachel Oren
- Department of Neuroscience, Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT 06510, United States
- Interdepartmental Neuroscience Program, Yale School of Medicine, New Haven, CT 06510, United States
| | - Michael J Higley
- Department of Neuroscience, Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT 06510, United States
| | - Jessica A Cardin
- Department of Neuroscience, Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT 06510, United States
| | - Farzad Noubary
- Department of Health Sciences, Northeastern University, Boston, MA 02115, United States
| | - Moritz Armbruster
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA 02111, United States
| | - Chris Dulla
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA 02111, United States
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4
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Wang C, Lin C, Zhao Y, Samantzis M, Sedlak P, Sah P, Balbi M. 40-Hz optogenetic stimulation rescues functional synaptic plasticity after stroke. Cell Rep 2023; 42:113475. [PMID: 37979173 DOI: 10.1016/j.celrep.2023.113475] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 10/18/2023] [Accepted: 11/03/2023] [Indexed: 11/20/2023] Open
Abstract
Evoked brain oscillations in the gamma range have been shown to assist in stroke recovery. However, the causal relationship between evoked oscillations and neuroprotection is not well understood. We have used optogenetic stimulation to investigate how evoked gamma oscillations modulate cortical dynamics in the acute phase after stroke. Our results reveal that stimulation at 40 Hz drives activity in interneurons at the stimulation frequency and phase-locked activity in principal neurons at a lower frequency, leading to increased cross-frequency coupling. In addition, 40-Hz stimulation after stroke enhances interregional communication. These effects are observed up to 24 h after stimulation. Our stimulation protocol also rescues functional synaptic plasticity 24 h after stroke and leads to an upregulation of plasticity genes and a downregulation of cell death genes. Together these results suggest that restoration of cortical dynamics may confer neuroprotection after stroke.
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Affiliation(s)
- Cong Wang
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4067, Australia; Engineering Research Centre of Traditional Chinese Medicine Intelligent Rehabilitation, Ministry of Education, Shanghai 201203, China
| | - Caixia Lin
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4067, Australia
| | - Yue Zhao
- Departments of Thoracic Surgery and State Key Laboratory of Genetic Engineering, Fudan University Shanghai Cancer Centre, Shanghai 200032, China; Institute of Thoracic Oncology, Fudan University, Shanghai 200032, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Montana Samantzis
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4067, Australia
| | - Petra Sedlak
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4067, Australia
| | - Pankaj Sah
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4067, Australia
| | - Matilde Balbi
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4067, Australia.
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5
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Mosneag IE, Flaherty SM, Wykes RC, Allan SM. Stroke and Translational Research - Review of Experimental Models with a Focus on Awake Ischaemic Induction and Anaesthesia. Neuroscience 2023:S0306-4522(23)00535-3. [PMID: 38065289 DOI: 10.1016/j.neuroscience.2023.11.034] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 11/28/2023] [Accepted: 11/30/2023] [Indexed: 12/17/2023]
Abstract
Animal models are an indispensable tool in the study of ischaemic stroke with hundreds of drugs emerging from the preclinical pipeline. However, all of these drugs have failed to translate into successful treatments in the clinic. This has brought into focus the need to enhance preclinical studies to improve translation. The confounding effects of anaesthesia on preclinical stroke modelling has been raised as an important consideration. Various volatile and injectable anaesthetics are used in preclinical models during stroke induction and for outcome measurements such as imaging or electrophysiology. However, anaesthetics modulate several pathways essential in the pathophysiology of stroke in a dose and drug dependent manner. Most notably, anaesthesia has significant modulatory effects on cerebral blood flow, metabolism, spreading depolarizations, and neurovascular coupling. To minimise anaesthetic complications and improve translational relevance, awake stroke induction has been attempted in limited models. This review outlines anaesthetic strategies employed in preclinical ischaemic rodent models and their reported cerebral effects. Stroke related complications are also addressed with a focus on infarct volume, neurological deficits, and thrombolysis efficacy. We also summarise routinely used focal ischaemic stroke rodent models and discuss the attempts to induce some of these models in awake rodents.
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Affiliation(s)
- Ioana-Emilia Mosneag
- Division of Neuroscience, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom; Geoffrey Jefferson Brain Research Centre, Manchester Academic Health Science Centre, Northern Care Alliance NHS Foundation Trust, University of Manchester, Manchester, United Kingdom.
| | - Samuel M Flaherty
- Division of Neuroscience, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom; Geoffrey Jefferson Brain Research Centre, Manchester Academic Health Science Centre, Northern Care Alliance NHS Foundation Trust, University of Manchester, Manchester, United Kingdom
| | - Robert C Wykes
- Division of Neuroscience, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom; Geoffrey Jefferson Brain Research Centre, Manchester Academic Health Science Centre, Northern Care Alliance NHS Foundation Trust, University of Manchester, Manchester, United Kingdom; Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Stuart M Allan
- Division of Neuroscience, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom; Geoffrey Jefferson Brain Research Centre, Manchester Academic Health Science Centre, Northern Care Alliance NHS Foundation Trust, University of Manchester, Manchester, United Kingdom
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6
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Brunner C, Montaldo G, Urban A. Functional ultrasound imaging of stroke in awake rats. eLife 2023; 12:RP88919. [PMID: 37988288 PMCID: PMC10662948 DOI: 10.7554/elife.88919] [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] [Indexed: 11/23/2023] Open
Abstract
Anesthesia is a major confounding factor in preclinical stroke research as stroke rarely occurs in sedated patients. Moreover, anesthesia affects both brain functions and the stroke outcome acting as neurotoxic or protective agents. So far, no approaches were well suited to induce stroke while imaging hemodynamics along with simultaneous large-scale recording of brain functions in awake animals. For this reason, the first critical hours following the stroke insult and associated functional alteration remain poorly understood. Here, we present a strategy to investigate both stroke hemodynamics and stroke-induced functional alterations without the confounding effect of anesthesia, i.e., under awake condition. Functional ultrasound (fUS) imaging was used to continuously monitor variations in cerebral blood volume (CBV) in +65 brain regions/hemispheres for up to 3 hr after stroke onset. The focal cortical ischemia was induced using a chemo-thrombotic agent suited for permanent middle cerebral artery occlusion in awake rats and followed by ipsi- and contralesional whiskers stimulation to investigate on the dynamic of the thalamocortical functions. Early (0-3 hr) and delayed (day 5) fUS recording enabled to characterize the features of the ischemia (location, CBV loss), spreading depolarizations (occurrence, amplitude) and functional alteration of the somatosensory thalamocortical circuits. Post-stroke thalamocortical functions were affected at both early and later time points (0-3 hr and 5 days) after stroke. Overall, our procedure facilitates early, continuous, and chronic assessments of hemodynamics and cerebral functions. When integrated with stroke studies or other pathological analyses, this approach seeks to enhance our comprehension of physiopathologies towards the development of pertinent therapeutic interventions.
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Affiliation(s)
- Clément Brunner
- Neuro-Electronics Research FlandersLeuvenBelgium
- Vlaams Instituut voor BiotechnologieLeuvenBelgium
- Interuniversity Microelectronics CentreLeuvenBelgium
- Department of Neurosciences, KU LeuvenLeuvenBelgium
| | - Gabriel Montaldo
- Neuro-Electronics Research FlandersLeuvenBelgium
- Vlaams Instituut voor BiotechnologieLeuvenBelgium
- Interuniversity Microelectronics CentreLeuvenBelgium
- Department of Neurosciences, KU LeuvenLeuvenBelgium
| | - Alan Urban
- Neuro-Electronics Research FlandersLeuvenBelgium
- Vlaams Instituut voor BiotechnologieLeuvenBelgium
- Interuniversity Microelectronics CentreLeuvenBelgium
- Department of Neurosciences, KU LeuvenLeuvenBelgium
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7
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Li J, Wu X, Fu Y, Nie H, Tang Z. Two-photon microscopy: application advantages and latest progress for in vivo imaging of neurons and blood vessels after ischemic stroke. Rev Neurosci 2023; 34:559-572. [PMID: 36719181 DOI: 10.1515/revneuro-2022-0127] [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: 10/15/2022] [Accepted: 01/02/2023] [Indexed: 02/01/2023]
Abstract
Two-photon microscopy (TPM) plays an important role in the study of the changes of the two important components of neurovascular units (NVU) - neurons and blood vessels after ischemic stroke (IS). IS refers to sudden neurological dysfunction caused by focal cerebral ischemia, which is one of the leading causes of death and disability worldwide. TPM is a new and rapidly developing high-resolution real-time imaging technique used in vivo that has attracted increasing attention from scientists in the neuroscience field. Neurons and blood vessels are important components of neurovascular units, and they undergo great changes after IS to respond to and compensate for ischemic injury. Here, we introduce the characteristics and pre-imaging preparations of TPM, and review the common methods and latest progress of TPM in the neuronal and vascular research for injury and recovery of IS in recent years. With the review, we clearly recognized that the most important advantage of TPM in the study of ischemic stroke is the ability to perform chronic longitudinal imaging of different tissues at a high resolution in vivo. Finally, we discuss the limitations of TPM and the technological advances in recent years.
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Affiliation(s)
- Jiarui Li
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, P. R. China
| | - Xuan Wu
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, P. R. China
| | - Yu Fu
- Department of Geriatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, P. R. China
| | - Hao Nie
- Department of Geriatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, P. R. China
| | - Zhouping Tang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, P. R. China
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8
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Adhikari Y, Ma CG, Chai Z, Jin X. Preventing development of post-stroke hyperexcitability by optogenetic or pharmacological stimulation of cortical excitatory activity. Neurobiol Dis 2023; 184:106233. [PMID: 37468047 DOI: 10.1016/j.nbd.2023.106233] [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: 02/20/2023] [Revised: 06/30/2023] [Accepted: 07/16/2023] [Indexed: 07/21/2023] Open
Abstract
Stroke is the most common cause of acquired epilepsy, but treatment for preventing the development of post-stroke epilepsy is still unavailable. Since stroke results in neuronal damage and death as well as initial loss of activity in the affected brain region, homeostatic plasticity may be trigged and contribute to an increase in network hyperexcitability that underlies epileptogenesis. Correspondingly, enhancing brain activity may inhibit hyperexcitability from enhanced homeostatic plasticity and prevent post-stroke epileptogenesis. To test these hypotheses, we first used in vivo two-photon and mesoscopic imaging of activity of cortical pyramidal neurons in Thy1-GCaMP6 transgenic mice to determine longitudinal changes in excitatory activity after a photothrombotic ischemic stroke. At 3-days post-stroke, there was a significant loss of neuronal activity in the peri-injury area as indicated by reductions in the frequency of calcium spikes and percentage of active neurons, which recovered to baseline level at day 7, supporting a homeostatic activity regulation of the surviving neurons in the peri-injury area. We further used optogenetic stimulation to specifically stimulate activity of pyramidal neurons in the peri-injury area of Thy-1 channelrhodopsin transgenic mice from day 5 to day 15 after stroke. Using pentylenetetrazole test to evaluate seizure susceptibility, we showed that stroke mice are more susceptible to Racine stage V seizures (time latency 54.3 ± 12.9 min) compared to sham mice (107.1 ± 13.6 min), but optogenetic stimulation reversed the increase in seizure susceptibility (114.0 ± 9.2 min) in mice with stroke. Similarly, administration of D-cycloserine, a partial N-methyl-d-aspartate (NMDA) receptor agonist that can mildly enhance neuronal activity without causing post-stroke seizure, from day 5 to day 15 after a stroke significantly reversed the increase in seizure susceptibility. The treatment also resulted in an increased survival of glutamic acid decarboxylase 67 (GAD67) positive interneurons and a reduced activation of glial fibrillary acidic protein (GFAP) positive reactive astrocytes. Thus, this study supports the involvement of homeostatic activity regulation in the development of post-stroke hyperexcitability and potential application of activity enhancement as a novel strategy to prevent post-stroke late-onset seizure and epilepsy through regulating cortical homeostatic plasticity.
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Affiliation(s)
- Yadav Adhikari
- Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN, USA; Schepens Eye Research Institute, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA.
| | - Cun-Gen Ma
- Shanxi Key Laboratory of Innovative Drug for the Treatment of Serious Diseases Basing on the Chronic Inflammation/Neurobiology Research Center, Shanxi University of Chinese Medicine, Jinzhong, Shanxi, China
| | - Zhi Chai
- Shanxi Key Laboratory of Innovative Drug for the Treatment of Serious Diseases Basing on the Chronic Inflammation/Neurobiology Research Center, Shanxi University of Chinese Medicine, Jinzhong, Shanxi, China
| | - Xiaoming Jin
- Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN, USA; Department of Anatomy, Cell Biology and Physiology, Indiana University School of Medicine, Indianapolis, IN, USA
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9
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Conti E, Carlini N, Piccardi B, Allegra Mascaro AL, Pavone FS. Photothrombotic Middle Cerebral Artery Occlusion in Mice: A Novel Model of Ischemic Stroke. eNeuro 2023; 10:ENEURO.0244-22.2022. [PMID: 36650068 PMCID: PMC9910575 DOI: 10.1523/eneuro.0244-22.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 10/25/2022] [Accepted: 11/06/2022] [Indexed: 01/19/2023] Open
Abstract
Stroke is one of the main causes of death and disability worldwide. Over the past decades, several animal models of focal cerebral ischemia have been developed allowing to investigate pathophysiological mechanisms underlying stroke progression. Despite intense preclinical research efforts, the need for noninvasive mouse models of vascular occlusion targeting the middle cerebral artery yet avoiding mechanical intervention is still pressing. Here, by applying the photothrombotic stroke model to the distal branch of the middle cerebral artery, we developed a novel strategy to induce a targeted occlusion of a large blood vessel in mice. This approach induces unilateral damage encompassing most of the dorsal cortex from the motor up to the visual regions 1 week after stroke. Pronounced limb dystonia one day after the damage is partially recovered after one week. Furthermore, we observe the insurgence of blood vessel leakage and edema formation in the peri-infarct area. Finally, this model elicits a notable inflammatory response revealed as a strong increase in astrocyte density and morphologic complexity in the perilesional region of the cortex compared with both other regions of the ipsilesional and contralesional hemispheres, and in sham-operated mice. To conclude, the stroke model we developed induces in mice the light-mediated occlusion of one of the main targets of human ischemic stroke, the middle cerebral artery, free from the limitations of commonly used preclinical models.
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Affiliation(s)
- Emilia Conti
- Neuroscience Institute, National Research Council, 56124 Pisa, Italy
- European Laboratory for Non-Linear Spectroscopy, 50019 Sesto Fiorentino, Italy
- Translational Research on Stroke (TREES) Working Group, Florence, Italy
| | - Noemi Carlini
- Neuroscience Institute, National Research Council, 56124 Pisa, Italy
- European Laboratory for Non-Linear Spectroscopy, 50019 Sesto Fiorentino, Italy
| | - Benedetta Piccardi
- Neurofarba Department, University of Florence, 50139 Florence, Italy
- Translational Research on Stroke (TREES) Working Group, Florence, Italy
| | - Anna Letizia Allegra Mascaro
- Neuroscience Institute, National Research Council, 56124 Pisa, Italy
- European Laboratory for Non-Linear Spectroscopy, 50019 Sesto Fiorentino, Italy
- Translational Research on Stroke (TREES) Working Group, Florence, Italy
| | - Francesco Saverio Pavone
- European Laboratory for Non-Linear Spectroscopy, 50019 Sesto Fiorentino, Italy
- Department of Physics and Astronomy, University of Florence, 50019 Sesto Fiorentino, Italy
- National Institute of Optics, National Research Council, 50019 Sesto Fiorentino, Italy
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10
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Yamada S, Wang Y, Monai H. Transcranial cortex-wide Ca 2+ imaging for the functional mapping of cortical dynamics. Front Neurosci 2023; 17:1119793. [PMID: 36875638 PMCID: PMC9975744 DOI: 10.3389/fnins.2023.1119793] [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: 12/09/2022] [Accepted: 01/30/2023] [Indexed: 02/17/2023] Open
Abstract
Visualization and tracking of the information flow in the broader brain area are essential because nerve cells make a vast network in the brain. Fluorescence Ca2+ imaging is a simultaneous visualization of brain cell activities in a wide area. Instead of classical chemical indicators, developing various types of transgenic animals that express Ca2+-sensitive fluorescent proteins enables us to observe brain activities in living animals at a larger scale for a long time. Multiple kinds of literature have reported that transcranial imaging of such transgenic animals is practical for monitoring the wide-field information flow across the broad brain regions, although it has a lower spatial resolution. Notably, this technique is helpful for the initial evaluation of cortical function in disease models. This review will introduce fully intact transcranial macroscopic imaging and cortex-wide Ca2+ imaging as practical applications.
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Affiliation(s)
- Serika Yamada
- Department of Biology, Faculty of Science, Ochanomizu University, Tokyo, Japan
| | - Yan Wang
- Graduate School of Humanities and Sciences, Ochanomizu University, Tokyo, Japan
| | - Hiromu Monai
- Department of Biology, Faculty of Science, Ochanomizu University, Tokyo, Japan.,Graduate School of Humanities and Sciences, Ochanomizu University, Tokyo, Japan
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11
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Wang Y, Tsai CH, Chu TS, Hung YT, Lee MY, Chen HH, Chen LT, Ger TR, Wang YH, Chiang NJ, Liao LD. Revisiting the cerebral hemodynamics of awake, freely moving rats with repeated ketamine self-administration using a miniature photoacoustic imaging system. NEUROPHOTONICS 2022; 9:045003. [PMID: 36338453 PMCID: PMC9623815 DOI: 10.1117/1.nph.9.4.045003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/08/2022] [Accepted: 09/21/2022] [Indexed: 06/16/2023]
Abstract
SIGNIFICANCE Revealing the dynamic associations between brain functions and behaviors is a significant challenge in neurotechnology, especially for awake subjects. Imaging cerebral hemodynamics in awake animal models is important because the collected data more realistically reflect human disease states. AIM We previously reported a miniature head-mounted scanning photoacoustic imaging (hmPAI) system. In the present study, we utilized this system to investigate the effects of ketamine on the cerebral hemodynamics of normal rats and rats subjected to prolonged ketamine self-administration. APPROACH The cortical superior sagittal sinus (SSS) was continuously monitored. The full-width at half-maximum (FWHM) of the photoacoustic (PA) A-line signal was used as an indicator of the SSS diameter, and the number of pixels in PA B-scan images was used to investigate changes in the cerebral blood volume (CBV). RESULTS We observed a significantly higher FWHM (blood vessel diameter) and CBV in normal rats injected with ketamine than in normal rats injected with saline. For rats subjected to prolonged ketamine self-administration, no significant changes in either the blood vessel diameter or CBV were observed. CONCLUSIONS The lack of significant change in prolonged ketamine-exposed rats was potentially due to an increased ketamine tolerance. Our device can reliably detect changes in the dilation of cortical blood vessels and the CBV. This study validates the utility of the developed hmPAI system in an awake, freely moving rat model for behavioral, cognitive, and preclinical cerebral disease studies.
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Affiliation(s)
- Yuhling Wang
- National Health Research Institutes, Institute of Biomedical Engineering and Nanomedicine, Zhunan Town, Miaoli County, Taiwan
| | - Chia-Hua Tsai
- National Health Research Institutes, Institute of Biomedical Engineering and Nanomedicine, Zhunan Town, Miaoli County, Taiwan
| | - Tsung-Sheng Chu
- National Health Research Institutes, Institute of Biomedical Engineering and Nanomedicine, Zhunan Town, Miaoli County, Taiwan
- Chung Yuan Christian University, Department of Biomedical Engineering, Taoyuan City, Taiwan
| | - Yun-Ting Hung
- National Health Research Institutes, Center for Neuropsychiatric Research, Zhunan Town, Miaoli County, Taiwan
| | - Mei-Yi Lee
- National Health Research Institutes, Center for Neuropsychiatric Research, Zhunan Town, Miaoli County, Taiwan
| | - Hwei-Hsien Chen
- National Health Research Institutes, Center for Neuropsychiatric Research, Zhunan Town, Miaoli County, Taiwan
| | - Li-Tzong Chen
- Kaohsiung Medical University, Kaohsiung Medical University Hospital, Kaohsiung City, Taiwan
- National Health Research Institutes, National Institute of Cancer Research, Zhunan Town, Miaoli County, Taiwan
| | - Tzong-Rong Ger
- Chung Yuan Christian University, Department of Biomedical Engineering, Taoyuan City, Taiwan
| | - Yung-Hsuan Wang
- National Health Research Institutes, National Institute of Cancer Research, Zhunan Town, Miaoli County, Taiwan
| | - Nai-Jung Chiang
- National Health Research Institutes, National Institute of Cancer Research, Zhunan Town, Miaoli County, Taiwan
- Taipei Veterans General Hospital, Department of Oncology, Taipei City, Taiwan
| | - Lun-De Liao
- National Health Research Institutes, Institute of Biomedical Engineering and Nanomedicine, Zhunan Town, Miaoli County, Taiwan
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Brondi M, Bruzzone M, Lodovichi C, dal Maschio M. Optogenetic Methods to Investigate Brain Alterations in Preclinical Models. Cells 2022; 11:cells11111848. [PMID: 35681542 PMCID: PMC9180859 DOI: 10.3390/cells11111848] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 05/27/2022] [Accepted: 05/31/2022] [Indexed: 02/05/2023] Open
Abstract
Investigating the neuronal dynamics supporting brain functions and understanding how the alterations in these mechanisms result in pathological conditions represents a fundamental challenge. Preclinical research on model organisms allows for a multiscale and multiparametric analysis in vivo of the neuronal mechanisms and holds the potential for better linking the symptoms of a neurological disorder to the underlying cellular and circuit alterations, eventually leading to the identification of therapeutic/rescue strategies. In recent years, brain research in model organisms has taken advantage, along with other techniques, of the development and continuous refinement of methods that use light and optical approaches to reconstruct the activity of brain circuits at the cellular and system levels, and to probe the impact of the different neuronal components in the observed dynamics. These tools, combining low-invasiveness of optical approaches with the power of genetic engineering, are currently revolutionizing the way, the scale and the perspective of investigating brain diseases. The aim of this review is to describe how brain functions can be investigated with optical approaches currently available and to illustrate how these techniques have been adopted to study pathological alterations of brain physiology.
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Affiliation(s)
- Marco Brondi
- Institute of Neuroscience, National Research Council-CNR, Viale G. Colombo 3, 35121 Padova, Italy; (M.B.); (C.L.)
- Veneto Institute of Molecular Medicine, Via Orus 2, 35129 Padova, Italy
| | - Matteo Bruzzone
- Department of Biomedical Sciences, Università degli Studi di Padova, Via U. Bassi 58B, 35121 Padova, Italy;
- Padova Neuroscience Center (PNC), Università degli Studi di Padova, Via Orus 2, 35129 Padova, Italy
| | - Claudia Lodovichi
- Institute of Neuroscience, National Research Council-CNR, Viale G. Colombo 3, 35121 Padova, Italy; (M.B.); (C.L.)
- Veneto Institute of Molecular Medicine, Via Orus 2, 35129 Padova, Italy
- Department of Biomedical Sciences, Università degli Studi di Padova, Via U. Bassi 58B, 35121 Padova, Italy;
- Padova Neuroscience Center (PNC), Università degli Studi di Padova, Via Orus 2, 35129 Padova, Italy
| | - Marco dal Maschio
- Department of Biomedical Sciences, Università degli Studi di Padova, Via U. Bassi 58B, 35121 Padova, Italy;
- Padova Neuroscience Center (PNC), Università degli Studi di Padova, Via Orus 2, 35129 Padova, Italy
- Correspondence:
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Hu Z, Li D, Zhong X, Li Y, Xuan A, Yu T, Zhu J, Zhu D. In vivo tissue optical clearing assisted through-skull targeted photothrombotic ischemic stroke model in mice. JOURNAL OF BIOMEDICAL OPTICS 2022; 27:065001. [PMID: 35676747 PMCID: PMC9174889 DOI: 10.1117/1.jbo.27.6.065001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 05/16/2022] [Indexed: 06/15/2023]
Abstract
SIGNIFICANCE Photothrombotic stroke is an important and widely used model for ischemic stroke research. However, the significant scattering of the skull during the procedure limits the light's ability to penetrate and focus on its target. Targeted photothrombosis uses surgery-based skull windows to obtain optical access to the brain, but it renders the brain's environment unnatural even before a stroke is established. AIM To establish a targeted, controllable ischemic stroke model in mice through an intact skull. APPROACH The in vivo skull optical clearing technique provides a craniotomy-free "optical window" that allows light to penetrate. Alongside the local photodynamic effect, we have established targeted photothrombosis without skull removal, effectively controlling the degree of thrombotic occlusion by changing the light dose. RESULTS Ex vivo and in vivo results demonstrated that skull optical clearing treatment significantly enhanced light's ability to penetrate the skull and focus on its target, contributing to thrombotic occlusion. The skull optical clearing window was also used for continuous blood flow mapping, and the relationship between light dose and injury degree was evaluated over 14 days of monitoring. Per our findings, increasing the light dose was accompanied by more severe infarction, indicating that the model was easily controllable. CONCLUSIONS Herein, a targeted, controllable ischemic stroke model was established by combinedly running an in vivo skull optical clearing technique and a photothrombotic procedure, avoiding unnecessary damage or environmental changes to the brain caused by surgery on the skull. Our established model should offer significant value to research on ischemic stroke.
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Affiliation(s)
- Zhengwu Hu
- Huazhong University of Science and Technology, Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Hubei, Wuhan, China
- Huazhong University of Science and Technology, MoE Key Laboratory for Biomedical Photonics, Hubei, Wuhan, China
- Optics Valley Laboratory, Hubei, China
| | - Dongyu Li
- Huazhong University of Science and Technology, Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Hubei, Wuhan, China
- Huazhong University of Science and Technology, MoE Key Laboratory for Biomedical Photonics, Hubei, Wuhan, China
- Optics Valley Laboratory, Hubei, China
| | - Xiang Zhong
- Huazhong University of Science and Technology, Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Hubei, Wuhan, China
- Huazhong University of Science and Technology, MoE Key Laboratory for Biomedical Photonics, Hubei, Wuhan, China
- Optics Valley Laboratory, Hubei, China
| | - Yusha Li
- Huazhong University of Science and Technology, Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Hubei, Wuhan, China
- Huazhong University of Science and Technology, MoE Key Laboratory for Biomedical Photonics, Hubei, Wuhan, China
- Optics Valley Laboratory, Hubei, China
| | - Ang Xuan
- Huazhong University of Science and Technology, Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Hubei, Wuhan, China
- Huazhong University of Science and Technology, MoE Key Laboratory for Biomedical Photonics, Hubei, Wuhan, China
- Optics Valley Laboratory, Hubei, China
| | - Tingting Yu
- Huazhong University of Science and Technology, Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Hubei, Wuhan, China
- Huazhong University of Science and Technology, MoE Key Laboratory for Biomedical Photonics, Hubei, Wuhan, China
- Optics Valley Laboratory, Hubei, China
| | - Jingtan Zhu
- Huazhong University of Science and Technology, Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Hubei, Wuhan, China
- Huazhong University of Science and Technology, MoE Key Laboratory for Biomedical Photonics, Hubei, Wuhan, China
- Optics Valley Laboratory, Hubei, China
| | - Dan Zhu
- Huazhong University of Science and Technology, Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Hubei, Wuhan, China
- Huazhong University of Science and Technology, MoE Key Laboratory for Biomedical Photonics, Hubei, Wuhan, China
- Optics Valley Laboratory, Hubei, China
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14
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Fukuda M, Matsumura T, Suda T, Hirase H. Depth-targeted intracortical microstroke by two-photon photothrombosis in rodent brain. NEUROPHOTONICS 2022; 9:021910. [PMID: 35311215 PMCID: PMC8929553 DOI: 10.1117/1.nph.9.2.021910] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Accepted: 02/24/2022] [Indexed: 05/21/2023]
Abstract
Significance: Photothrombosis is a widely used model of ischemic stroke in rodent experiments. In the photothrombosis model, the photosensitizer rose bengal (RB) is systemically introduced into the blood stream and activated by green light to induce aggregation of platelets that eventually cause vessel occlusion. Since the activation of RB is a one-photon phenomenon and the molecules in the illuminated area (light path) are subject to excitation, targeting of thrombosis is unspecific, especially in the depth dimension. We developed a photothrombosis protocol that can target a single vessel in the cortical parenchyma by two-photon excitation. Aim: We aim to induce a thrombotic stroke in the cortical parenchyma by two-photon activation of RB to confine photothrombosis within a vessel of a target depth. Approach: FITC-dextran is injected into the blood stream to visualize the cerebral blood flow in anesthetized adult mice with a cranial window. After a target vessel is chosen by two-photon imaging (950 nm), RB is injected into the blood stream. The scanning wavelength is changed to 720 nm, and photothrombosis is induced by scanning the target vessel. Results: Two-photon depth-targeted single-vessel photothrombosis was achieved with a success rate of 84.9 % ± 1.7 % and an irradiation duration of < 80 s . Attempts without RB (i.e., only with FITC) did not result in photothrombosis at the excitation wavelength of 720 nm. Conclusions: We described a protocol that achieves depth-targeted single-vessel photothrombosis by two-photon excitation. Simultaneous imaging of blood flow in the targeted vessel using FITC dextran enabled the confirmation of vessel occlusion and prevention of excess irradiation that possibly induces unintended photodamage.
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Affiliation(s)
- Masahiro Fukuda
- Kumamoto University, International Research Center for Medical Sciences, Kumamoto, Japan
- Duke-NUS Medical School, Signature Program in Neuroscience and Behavioral Disorders, Singapore
- Address all correspondence to Masahiro Fukuda, ; Hajime Hirase,
| | - Takayoshi Matsumura
- Jichi Medical University, Division of Inflammation Research, Center for Molecular Medicine, Tochigi, Japan
- National University of Singapore, Cancer Science Institute of Singapore, Singapore
| | - Toshio Suda
- Kumamoto University, International Research Center for Medical Sciences, Kumamoto, Japan
- National University of Singapore, Cancer Science Institute of Singapore, Singapore
| | - Hajime Hirase
- University of Copenhagen, Center for Translational Neuromedicine, Faculty of Health and Life Sciences, Copenhagen, Denmark
- Address all correspondence to Masahiro Fukuda, ; Hajime Hirase,
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15
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Sullender CT, Richards LM, He F, Luan L, Dunn AK. Dynamics of isoflurane-induced vasodilation and blood flow of cerebral vasculature revealed by multi-exposure speckle imaging. J Neurosci Methods 2022; 366:109434. [PMID: 34863840 PMCID: PMC9258779 DOI: 10.1016/j.jneumeth.2021.109434] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 11/12/2021] [Accepted: 11/29/2021] [Indexed: 10/19/2022]
Abstract
BACKGROUND Anesthetized animal models are used extensively during neurophysiological and behavioral studies despite systemic effects from anesthesia that undermine both accurate interpretation and translation to awake human physiology. The majority of work examining the impact of anesthesia on cerebral blood flow (CBF) has been restricted to before and after measurements with limited spatial resolution. NEW METHOD We used multi-exposure speckle imaging (MESI), an advanced form of laser speckle contrast imaging (LSCI), to characterize the dynamics of isoflurane anesthesia induction on cerebral vasculature and blood flow in the mouse brain. RESULTS The large anatomical changes caused by isoflurane are depicted with wide-field imagery and video highlighting the induction of general anesthesia. Within minutes of exposure, both vessel diameter and blood flow increased drastically compared to the awake state and remained elevated for the duration of imaging. An examination of the dynamics of anesthesia induction reveals that blood flow increased faster in arteries than in veins or parenchyma regions. COMPARISON WITH EXISTING METHODS MESI offers robust hemodynamic measurements across large fields-of-view and high temporal resolutions sufficient for continuous visualization of cerebrovascular events featuring major changes in blood flow. CONCLUSION The large alterations caused by isoflurane anesthesia to the cortical vasculature and CBF are readily characterized using MESI. These changes are unrepresentative of normal physiology and provide further evidence that neuroscience experiments would benefit from transitioning to un-anesthetized awake animal models.
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Affiliation(s)
- Colin T Sullender
- Department of Biomedical Engineering, University of Texas at Austin, 107 W. Dean Keeton Street Stop C0800, Austin, TX 78712, United States
| | - Lisa M Richards
- Department of Biomedical Engineering, University of Texas at Austin, 107 W. Dean Keeton Street Stop C0800, Austin, TX 78712, United States
| | - Fei He
- Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, TX 77005, United States
| | - Lan Luan
- Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, TX 77005, United States; Department of Bioengineering, Rice University, 6100 Main Street, Houston, TX 77005, United States
| | - Andrew K Dunn
- Department of Biomedical Engineering, University of Texas at Austin, 107 W. Dean Keeton Street Stop C0800, Austin, TX 78712, United States.
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16
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Conti E, Piccardi B, Sodero A, Tudisco L, Lombardo I, Fainardi E, Nencini P, Sarti C, Allegra Mascaro AL, Baldereschi M. Translational Stroke Research Review: Using the Mouse to Model Human Futile Recanalization and Reperfusion Injury in Ischemic Brain Tissue. Cells 2021; 10:3308. [PMID: 34943816 PMCID: PMC8699609 DOI: 10.3390/cells10123308] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 11/17/2021] [Accepted: 11/19/2021] [Indexed: 12/20/2022] Open
Abstract
The approach to reperfusion therapies in stroke patients is rapidly evolving, but there is still no explanation why a substantial proportion of patients have a poor clinical prognosis despite successful flow restoration. This issue of futile recanalization is explained here by three clinical cases, which, despite complete recanalization, have very different outcomes. Preclinical research is particularly suited to characterize the highly dynamic changes in acute ischemic stroke and identify potential treatment targets useful for clinical translation. This review surveys the efforts taken so far to achieve mouse models capable of investigating the neurovascular underpinnings of futile recanalization. We highlight the translational potential of targeting tissue reperfusion in fully recanalized mouse models and of investigating the underlying pathophysiological mechanisms from subcellular to tissue scale. We suggest that stroke preclinical research should increasingly drive forward a continuous and circular dialogue with clinical research. When the preclinical and the clinical stroke research are consistent, translational success will follow.
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Affiliation(s)
- Emilia Conti
- Neuroscience Institute, National Research Council, Via G. Moruzzi 1, 56124 Pisa, Italy; (E.C.); (A.L.A.M.)
- European Laboratory for Non-Linear Spectroscopy, Via Nello Carrara 1, 50019 Sesto Fiorentino, Italy
| | - Benedetta Piccardi
- Neurofarba Department, University of Florence, Via G. Pieraccini 6, 50139 Florence, Italy; (A.S.); (L.T.); (C.S.)
| | - Alessandro Sodero
- Neurofarba Department, University of Florence, Via G. Pieraccini 6, 50139 Florence, Italy; (A.S.); (L.T.); (C.S.)
| | - Laura Tudisco
- Neurofarba Department, University of Florence, Via G. Pieraccini 6, 50139 Florence, Italy; (A.S.); (L.T.); (C.S.)
| | - Ivano Lombardo
- Department of Biomedical, Experimental and Clinical Sciences, University of Florence, Viale Morgagni 50, 50134 Florence, Italy; (I.L.); (E.F.)
| | - Enrico Fainardi
- Department of Biomedical, Experimental and Clinical Sciences, University of Florence, Viale Morgagni 50, 50134 Florence, Italy; (I.L.); (E.F.)
| | - Patrizia Nencini
- Stroke Unit, Careggi University Hospital, Largo Brambilla 3, 50134 Florence, Italy;
| | - Cristina Sarti
- Neurofarba Department, University of Florence, Via G. Pieraccini 6, 50139 Florence, Italy; (A.S.); (L.T.); (C.S.)
| | - Anna Letizia Allegra Mascaro
- Neuroscience Institute, National Research Council, Via G. Moruzzi 1, 56124 Pisa, Italy; (E.C.); (A.L.A.M.)
- European Laboratory for Non-Linear Spectroscopy, Via Nello Carrara 1, 50019 Sesto Fiorentino, Italy
| | - Marzia Baldereschi
- Neuroscience Institute, National Research Council, Via Madonna del Piano 10, 50019 Sesto Fiorentino, Italy;
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17
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Zhao HT, Tuohy MC, Chow D, Kozberg MG, Kim SH, Shaik MA, Hillman EMC. Neurovascular dynamics of repeated cortical spreading depolarizations after acute brain injury. Cell Rep 2021; 37:109794. [PMID: 34610299 PMCID: PMC8590206 DOI: 10.1016/j.celrep.2021.109794] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 06/30/2021] [Accepted: 09/14/2021] [Indexed: 11/30/2022] Open
Abstract
Cortical spreading depolarizations (CSDs) are increasingly suspected to play an exacerbating role in a range of acute brain injuries, including stroke, possibly through their interactions with cortical blood flow. We use simultaneous wide-field imaging of neural activity and hemodynamics in Thy1-GCaMP6f mice to explore the neurovascular dynamics of CSDs during and following Rose Bengal-mediated photothrombosis. CSDs are observed in all mice as slow-moving waves of GCaMP fluorescence extending far beyond the photothrombotic area. Initial CSDs are accompanied by profound vasoconstriction and leave residual oligemia and ischemia in their wake. Later, CSDs evoke variable responses, from constriction to biphasic to vasodilation. However, CSD-evoked vasoconstriction is found to be more likely during rapid, high-amplitude CSDs in regions with stronger oligemia and ischemia, which, in turn, worsens after each repeated CSD. This feedback loop may explain the variable but potentially devastating effects of CSDs in the context of acute brain injury. Zhao et al. use wide-field optical mapping of neuronal and hemodynamic activity in mice, capturing CSDs immediately following photothrombosis. Initial CSDs are accompanied by strong vasoconstriction, leaving persistent oligemia and ischemia. Region-dependent neurovascular responses to subsequent CSDs demonstrate a potential vicious cycle of CSD-dependent damage in acute brain injury.
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Affiliation(s)
- Hanzhi T Zhao
- Laboratory for Functional Optical Imaging, Mortimer B. Zuckerman Mind Brain Behavior Institute, Departments of Biomedical Engineering and Radiology, Columbia University, New York, NY 10027, USA
| | - Mary Claire Tuohy
- Laboratory for Functional Optical Imaging, Mortimer B. Zuckerman Mind Brain Behavior Institute, Departments of Biomedical Engineering and Radiology, Columbia University, New York, NY 10027, USA
| | - Daniel Chow
- Laboratory for Functional Optical Imaging, Mortimer B. Zuckerman Mind Brain Behavior Institute, Departments of Biomedical Engineering and Radiology, Columbia University, New York, NY 10027, USA
| | - Mariel G Kozberg
- Laboratory for Functional Optical Imaging, Mortimer B. Zuckerman Mind Brain Behavior Institute, Departments of Biomedical Engineering and Radiology, Columbia University, New York, NY 10027, USA
| | - Sharon H Kim
- Laboratory for Functional Optical Imaging, Mortimer B. Zuckerman Mind Brain Behavior Institute, Departments of Biomedical Engineering and Radiology, Columbia University, New York, NY 10027, USA
| | - Mohammed A Shaik
- Laboratory for Functional Optical Imaging, Mortimer B. Zuckerman Mind Brain Behavior Institute, Departments of Biomedical Engineering and Radiology, Columbia University, New York, NY 10027, USA
| | - Elizabeth M C Hillman
- Laboratory for Functional Optical Imaging, Mortimer B. Zuckerman Mind Brain Behavior Institute, Departments of Biomedical Engineering and Radiology, Columbia University, New York, NY 10027, USA.
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18
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Mirza Agha B, Akbary R, Ghasroddashti A, Nazari-Ahangarkolaee M, Whishaw IQ, Mohajerani MH. Cholinergic upregulation by optogenetic stimulation of nucleus basalis after photothrombotic stroke in forelimb somatosensory cortex improves endpoint and motor but not sensory control of skilled reaching in mice. J Cereb Blood Flow Metab 2021; 41:1608-1622. [PMID: 33103935 PMCID: PMC8221755 DOI: 10.1177/0271678x20968930] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A network of cholinergic neurons in the basal forebrain innerve the forebrain and are proposed to contribute to a variety of functions including cortical plasticity, attention, and sensorimotor behavior. This study examined the contribution of the nucleus basalis cholinergic projection to the sensorimotor cortex on recovery on a skilled reach-to-eat task following photothrombotic stroke in the forelimb region of the somatosensory cortex. Mice were trained to perform a single pellet skilled reaching task and their pre and poststroke performance, from Day 4 to Day 28 poststroke, was assessed frame-by-frame by video analysis with endpoint, movement and sensorimotor integration measures. Somatosensory forelimb lesions produced impairments in endpoint and movement component measures of reaching and increased the incidence of fictive eating, a sensory impairment in mistaking a missed reach for a successful reach. Upregulated acetylcholine (ACh) release, as measured by local field potential recording, elicited via optogenetic stimulation of the nucleus basalis improved recovery of reaching and improved movement scores but did not affect sensorimotor integration impairment poststroke. The results show that the mouse cortical forelimb somatosensory region contributes to forelimb motor behavior and suggest that ACh upregulation could serve as an adjunct to behavioral therapy for acute treatment of stroke.
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Affiliation(s)
- Behroo Mirza Agha
- Department of Neuroscience, Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, Alberta, Canada
| | - Roya Akbary
- Department of Psychology, University of Toronto, Toronto, Ontario, Canada
| | - Arashk Ghasroddashti
- Department of Neuroscience, Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, Alberta, Canada
| | - Mojtaba Nazari-Ahangarkolaee
- Department of Neuroscience, Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, Alberta, Canada
| | - Ian Q Whishaw
- Department of Neuroscience, Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, Alberta, Canada
| | - Majid H Mohajerani
- Department of Neuroscience, Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, Alberta, Canada
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19
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Sun Y, Chen H, Lin Y. Rehabilitation training inhibits neuronal apoptosis by down-regulation of TLR4/MyD88 signaling pathway in mice with cerebral ischemic stroke. Am J Transl Res 2021; 13:2213-2223. [PMID: 34017384 PMCID: PMC8129365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 02/09/2021] [Indexed: 06/12/2023]
Abstract
OBJECTIVE To investigate the role of rehabilitation training and TLR4/MyD88 signaling pathway on neuronal apoptosis in mice with cerebral ischemic stroke. METHODS Mice were randomized into six groups, which were normal group (healthy mice, n=20), control group (sham surgery, n=20), model group (middle cerebral artery occlusion (MCAO) model, n=20), training (MCAO model, continuous rehabilitation training for 4 weeks, n=20), TAK-242 group (MCAO model, TL R4 inhibitor TAK-242, n=20), and TAK-242 + Training group (MCAO model, TLR4 inhibitor TAK-242 + rehabilitation training, n=20). RESULTS Neurobehavioral assessment was performed, and cerebral infarction area of mice was detected by triphenyl tetrazolium chloride staining. Compared with the normal group, no significant differences in all indicators were found in the control group (all P>0.05), while the other groups had higher neurological function scores, cerebral infarction area, neuronal apoptosis rate, increased expressions of TLR4, MyD88, Bax, NF-κB, TNF-α, Caspase-3, IL-1βA and decreased mRNA and protein expressions of Bcl-2 (all P<0.05). CONCLUSION Rehabilitation training can effectively reduce the apoptosis of hippocampal neurons in mice with ischemic stroke by inhibiting the TLR4/MyD88 signaling pathway.
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Affiliation(s)
- Yan Sun
- School of Rehabilitation Medicine, He’nan University of Chinese MedicineZhengzhou, He’nan Province, China
| | - Hai Chen
- Department of Children’s Rehabilitation, The Third Affiliated Hospital of Zhengzhou UniversityZhengzhou, He’nan Province, China
| | - Yibing Lin
- Shaoxing Institute of Traditional Chinese Medicine Culture, Shaoxing Hospital of Traditional Chinese MedicineShaoxing, Zhejiang Province, China
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20
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Gamma frequency activation of inhibitory neurons in the acute phase after stroke attenuates vascular and behavioral dysfunction. Cell Rep 2021; 34:108696. [PMID: 33535035 DOI: 10.1016/j.celrep.2021.108696] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 11/06/2020] [Accepted: 01/06/2021] [Indexed: 11/24/2022] Open
Abstract
Alterations in gamma oscillations occur in several neurological disorders, and the entrainment of gamma oscillations has been recently proposed as a treatment for neurodegenerative disease. Optogenetic stimulation enhances recovery in models of stroke when applied weeks after injury; however, the benefits of acute brain stimulation have not been investigated. Here, we report beneficial effects of gamma-frequency modulation in the acute phase, within 1 h, after stroke. Transgenic VGAT-ChR2 mice are subject to awake photothrombotic stroke in an area encompassing the forelimb sensory and motor cortex. Optogenetic stimulation at 40 Hz in the peri-infarct zone recovers neuronal activity 24 h after stroke in motor and parietal association areas, as well as blood flow over the first week after stroke. Stimulation significantly reduces lesion volume and improves motor function. Our results suggest that acute-phase modulation of cortical oscillatory dynamics may serve as a target for neuroprotection against stroke.
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21
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Nelson AN, Calhoun MS, Thomas AM, Tavares JL, Ferretti DM, Dillon GM, Mandelblat-Cerf Y. Temporal Progression of Excitotoxic Calcium Following Distal Middle Cerebral Artery Occlusion in Freely Moving Mice. Front Cell Neurosci 2021; 14:566789. [PMID: 33424552 DOI: 10.3389/fncel.2020.566789] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 10/26/2020] [Indexed: 11/13/2022] Open
Abstract
Ischemic stroke is recognized as one of the leading causes of adult disability, morbidity, and death worldwide. Following stroke, acute neuronal excitotoxicity can lead to many deleterious consequences, one of which is the dysregulation of intracellular calcium ultimately culminating in cell death. However, to develop neuroprotective treatments that target neuronal excitotoxicity, it is essential to know the therapeutic time window for intervention following an ischemic event. To address this question, the current study aimed to characterize the magnitude and temporal progression of neuronal intracellular calcium observed following distal middle cerebral artery occlusion (dMCAO) in mice. Using the calcium fluorescence indicator, GCaMP, we tracked neuronal population response in freely moving animals immediately following dMCAO in both the core infarct and peri-infarct regions. Our results demonstrate that calcium excitotoxicity following artery occlusion can be generally characterized by two phases: a transient increase in activity that lasts tens of minutes, followed by a long, slow sustained increase in fluorescence signal. The first phase is primarily thought to represent neuronal hyperexcitability, defining our therapeutic window, while the second may represent gradual cell death. Importantly, we show that the level of intracellular calcium following artery occlusion correlated with the infarct size at 24 h demonstrating a direct connection between excitotoxicity and cell death in our stroke model. In addition, we show that administration of the NMDA antagonist MK-801 resulted in both a decrease in calcium signal and a subsequent reduction in the infarct size. Altogether, this study represents the first demonstration in freely moving animals characterizing the temporal progression of toxic calcium signaling following artery occlusion. In addition, these results define a critical time window for neuroprotective therapeutic intervention in mice.
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22
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The Home-Cage Automated Skilled Reaching Apparatus (HASRA): Individualized Training of Group-Housed Mice in a Single Pellet Reaching Task. eNeuro 2020; 7:ENEURO.0242-20.2020. [PMID: 33008812 PMCID: PMC7581188 DOI: 10.1523/eneuro.0242-20.2020] [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: 06/04/2020] [Revised: 08/21/2020] [Accepted: 09/08/2020] [Indexed: 01/04/2023] Open
Abstract
The single pellet reaching task is commonly used in rodents to assess the acquisition of fine motor skill and recovery of function following nervous system injury. Although this task is useful for gauging skilled forelimb use in rodents, the process of training animals is labor intensive and variable across studies and labs. To address these limitations, we developed a single pellet reaching paradigm for training and testing group housed mice within their home cage. Mice enter a training compartment attached to the outside of the cage and retrieve millet seeds presented on a motorized pedestal that can be individually positioned to present seeds to either forelimb. To identify optimal training parameters, we compared task participation and success rates between groups of animals that were presented seeds at two different heights (floor vs mouth height) and at different intervals (fixed-time vs trial-based). The mouth height/fixed interval presentation style was most effective at promoting reaching behavior as all mice reached for seeds within 5 d. Using this paradigm, we assessed stroke-induced deficits in home-cage reaching. Following three weeks of baseline training, reaching success rate was ∼40%, with most trials performed during the dark cycle. A forelimb motor cortex stroke significantly decreased interaction with presented seeds within the first 2 d and impaired reaching success rates for the first 7 d. Our data demonstrate that group-housed mice can be efficiently trained on a single pellet reaching task in the home cage and that this assay is sensitive to stroke induced motor impairments.
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Kostyuk AI, Kokova AD, Podgorny OV, Kelmanson IV, Fetisova ES, Belousov VV, Bilan DS. Genetically Encoded Tools for Research of Cell Signaling and Metabolism under Brain Hypoxia. Antioxidants (Basel) 2020; 9:E516. [PMID: 32545356 PMCID: PMC7346190 DOI: 10.3390/antiox9060516] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Revised: 06/04/2020] [Accepted: 06/06/2020] [Indexed: 02/08/2023] Open
Abstract
Hypoxia is characterized by low oxygen content in the tissues. The central nervous system (CNS) is highly vulnerable to a lack of oxygen. Prolonged hypoxia leads to the death of brain cells, which underlies the development of many pathological conditions. Despite the relevance of the topic, different approaches used to study the molecular mechanisms of hypoxia have many limitations. One promising lead is the use of various genetically encoded tools that allow for the observation of intracellular parameters in living systems. In the first part of this review, we provide the classification of oxygen/hypoxia reporters as well as describe other genetically encoded reporters for various metabolic and redox parameters that could be implemented in hypoxia studies. In the second part, we discuss the advantages and disadvantages of the primary hypoxia model systems and highlight inspiring examples of research in which these experimental settings were combined with genetically encoded reporters.
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Affiliation(s)
- Alexander I. Kostyuk
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 117997 Moscow, Russia; (A.I.K.); (A.D.K.); (O.V.P.); (I.V.K.); (E.S.F.); (V.V.B.)
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
| | - Aleksandra D. Kokova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 117997 Moscow, Russia; (A.I.K.); (A.D.K.); (O.V.P.); (I.V.K.); (E.S.F.); (V.V.B.)
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
| | - Oleg V. Podgorny
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 117997 Moscow, Russia; (A.I.K.); (A.D.K.); (O.V.P.); (I.V.K.); (E.S.F.); (V.V.B.)
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
- Koltzov Institute of Developmental Biology, 119334 Moscow, Russia
| | - Ilya V. Kelmanson
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 117997 Moscow, Russia; (A.I.K.); (A.D.K.); (O.V.P.); (I.V.K.); (E.S.F.); (V.V.B.)
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
| | - Elena S. Fetisova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 117997 Moscow, Russia; (A.I.K.); (A.D.K.); (O.V.P.); (I.V.K.); (E.S.F.); (V.V.B.)
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
- Faculty of Biology, Lomonosov Moscow State University, 119992 Moscow, Russia
| | - Vsevolod V. Belousov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 117997 Moscow, Russia; (A.I.K.); (A.D.K.); (O.V.P.); (I.V.K.); (E.S.F.); (V.V.B.)
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
- Institute for Cardiovascular Physiology, Georg August University Göttingen, D-37073 Göttingen, Germany
- Federal Center for Cerebrovascular Pathology and Stroke, 117997 Moscow, Russia
| | - Dmitry S. Bilan
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 117997 Moscow, Russia; (A.I.K.); (A.D.K.); (O.V.P.); (I.V.K.); (E.S.F.); (V.V.B.)
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
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Sunil S, Erdener SE, Lee BS, Postnov D, Tang J, Kura S, Cheng X, Chen IA, Boas DA, Kılıç K. Awake chronic mouse model of targeted pial vessel occlusion via photothrombosis. NEUROPHOTONICS 2020; 7:015005. [PMID: 32042854 PMCID: PMC6992450 DOI: 10.1117/1.nph.7.1.015005] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 01/02/2020] [Indexed: 05/09/2023]
Abstract
Animal models of stroke are used extensively to study the mechanisms involved in the acute and chronic phases of recovery following stroke. A translatable animal model that closely mimics the mechanisms of a human stroke is essential in understanding recovery processes as well as developing therapies that improve functional outcomes. We describe a photothrombosis stroke model that is capable of targeting a single distal pial branch of the middle cerebral artery with minimal damage to the surrounding parenchyma in awake head-fixed mice. Mice are implanted with chronic cranial windows above one hemisphere of the brain that allow optical access to study recovery mechanisms for over a month following occlusion. Additionally, we study the effect of laser spot size used for occlusion and demonstrate that a spot size with small axial and lateral resolution has the advantage of minimizing unwanted photodamage while still monitoring macroscopic changes to cerebral blood flow during photothrombosis. We show that temporally guiding illumination using real-time feedback of blood flow dynamics also minimized unwanted photodamage to the vascular network. Finally, through quantifiable behavior deficits and chronic imaging we show that this model can be used to study recovery mechanisms or the effects of therapeutics longitudinally.
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Affiliation(s)
- Smrithi Sunil
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
- Address all correspondence to Smrithi Sunil, E-mail:
| | - Sefik Evren Erdener
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
- Hacettepe University, Institute of Neurological Sciences and Psychiatry, Ankara, Turkey
| | - Blaire S. Lee
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Dmitry Postnov
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
- Copenhagen University, Department of Biomedical Sciences, Copenhagen, Denmark
| | - Jianbo Tang
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Sreekanth Kura
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Xiaojun Cheng
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Ichun Anderson Chen
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - David A. Boas
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Kıvılcım Kılıç
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
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25
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Balbi M, Vanni MP, Vega MJ, Silasi G, Sekino Y, Boyd JD, LeDue JM, Murphy TH. Longitudinal monitoring of mesoscopic cortical activity in a mouse model of microinfarcts reveals dissociations with behavioral and motor function. J Cereb Blood Flow Metab 2019; 39:1486-1500. [PMID: 29521138 PMCID: PMC6681536 DOI: 10.1177/0271678x18763428] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 01/29/2018] [Accepted: 02/01/2018] [Indexed: 12/14/2022]
Abstract
Small vessel disease is characterized by sporadic obstruction of small vessels leading to neuronal cell death. These microinfarcts often escape detection by conventional magnetic resonance imaging and are identified only upon postmortem examination. Our work explores a brain-wide microinfarct model in awake head-fixed mice, where occlusions of small penetrating arterioles are reproduced by endovascular injection of fluorescent microspheres. Mesoscopic functional connectivity was mapped longitudinally in awake GCaMP6 mice using genetically encoded calcium indicators for transcranial wide-field calcium imaging. Microsphere occlusions were quantified and changes in cerebral blood flow were measured with laser speckle imaging. The neurodeficit score in microinfarct mice was significantly higher than in sham, indicating impairment in motor function. The novel object recognition test showed a reduction in the discrimination index in microinfarct mice compared to sham. Graph-theoretic analysis of functional connectivity did not reveal significant differences in functional connectivity between sham and microinfarct mice. While behavioral tasks revealed impairments following microinfarct induction, the absence of measurable functional alterations in cortical activity has a less straightforward interpretation. The behavioral alterations produced by this model are consistent with alterations observed in human patients suffering from microinfarcts and support the validity of microsphere injection as a microinfarct model.
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Affiliation(s)
- Matilde Balbi
- Department of Psychiatry, Kinsmen
Laboratory of Neurological Research, University of British Columbia, Vancouver,
British Columbia, Canada
| | - Matthieu P Vanni
- Department of Psychiatry, Kinsmen
Laboratory of Neurological Research, University of British Columbia, Vancouver,
British Columbia, Canada
| | - Max J Vega
- Department of Psychology, Motivated
Cognition Lab, University of British Columbia, Vancouver, British Columbia,
Canada
| | - Gergely Silasi
- Department of Psychiatry, Kinsmen
Laboratory of Neurological Research, University of British Columbia, Vancouver,
British Columbia, Canada
| | - Yuki Sekino
- Department of Psychiatry, Kinsmen
Laboratory of Neurological Research, University of British Columbia, Vancouver,
British Columbia, Canada
| | - Jamie D Boyd
- Department of Psychiatry, Kinsmen
Laboratory of Neurological Research, University of British Columbia, Vancouver,
British Columbia, Canada
| | - Jeffrey M LeDue
- Department of Psychiatry, Kinsmen
Laboratory of Neurological Research, University of British Columbia, Vancouver,
British Columbia, Canada
- Djavad Mowafaghian Center for Brain
Health, University of British Columbia, Vancouver, British Columbia, Canada
| | - Timothy H Murphy
- Department of Psychiatry, Kinsmen
Laboratory of Neurological Research, University of British Columbia, Vancouver,
British Columbia, Canada
- Djavad Mowafaghian Center for Brain
Health, University of British Columbia, Vancouver, British Columbia, Canada
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26
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In Vivo Imaging of CNS Injury and Disease. J Neurosci 2017; 37:10808-10816. [PMID: 29118209 DOI: 10.1523/jneurosci.1826-17.2017] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Revised: 10/02/2017] [Accepted: 10/03/2017] [Indexed: 02/06/2023] Open
Abstract
In vivo optical imaging has emerged as a powerful tool with which to study cellular responses to injury and disease in the mammalian CNS. Important new insights have emerged regarding axonal degeneration and regeneration, glial responses and neuroinflammation, changes in the neurovascular unit, and, more recently, neural transplantations. Accompanying a 2017 SfN Mini-Symposium, here, we discuss selected recent advances in understanding the neuronal, glial, and other cellular responses to CNS injury and disease with in vivo imaging of the rodent brain or spinal cord. We anticipate that in vivo optical imaging will continue to be at the forefront of breakthrough discoveries of fundamental mechanisms and therapies for CNS injury and disease.
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27
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Automated touch sensing in the mouse tapered beam test using Raspberry Pi. J Neurosci Methods 2017; 291:221-226. [DOI: 10.1016/j.jneumeth.2017.08.030] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 08/23/2017] [Accepted: 08/24/2017] [Indexed: 01/30/2023]
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