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Uhlířová H, Stibůrek M, Pikálek T, Gomes A, Turtaev S, Kolbábková P, Čižmár T. "There's plenty of room at the bottom": deep brain imaging with holographic endo-microscopy. NEUROPHOTONICS 2024; 11:S11504. [PMID: 38250297 PMCID: PMC10798506 DOI: 10.1117/1.nph.11.s1.s11504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 12/09/2023] [Accepted: 12/14/2023] [Indexed: 01/23/2024]
Abstract
Significance Over more than 300 years, microscopic imaging keeps providing fundamental insights into the mechanisms of living organisms. Seeing microscopic structures beyond the reach of free-space light-based microscopy, however, requires dissection of the tissue-an intervention seriously disturbing its physiological functions. The hunt for low-invasiveness tools has led a growing community of physicists and engineers into the realm of complex media photonics. One of its activities represents exploiting multimode optical fibers (MMFs) as ultra-thin endoscopic probes. Employing wavefront shaping, these tools only recently facilitated the first peeks at cells and their sub-cellular compartments at the bottom of the mouse brain with the impact of micro-scale tissue damage. Aim Here, we aim to highlight advances in MMF-based holographic endo-microscopy facilitating microscopic imaging throughout the whole depth of the mouse brain. Approach We summarize the important technical and methodological prerequisites for stabile high-resolution imaging in vivo. Results We showcase images of the microscopic building blocks of brain tissue, including neurons, neuronal processes, vessels, intracellular calcium signaling, and red blood cell velocity in individual vessels. Conclusions This perspective article helps to understand the complexity behind the technology of holographic endo-microscopy, summarizes its recent advances and challenges, and stimulates the mind of the reader for further exploitation of this tool in the neuroscience research.
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Affiliation(s)
- Hana Uhlířová
- Institute of Scientific Instruments of the Czech Academy of Sciences, Brno, Czech Republic
| | - Miroslav Stibůrek
- Institute of Scientific Instruments of the Czech Academy of Sciences, Brno, Czech Republic
| | - Tomáš Pikálek
- Institute of Scientific Instruments of the Czech Academy of Sciences, Brno, Czech Republic
| | - André Gomes
- Leibniz Institute of Photonic Technology, Jena, Germany
| | | | - Petra Kolbábková
- Institute of Scientific Instruments of the Czech Academy of Sciences, Brno, Czech Republic
| | - Tomáš Čižmár
- Institute of Scientific Instruments of the Czech Academy of Sciences, Brno, Czech Republic
- Leibniz Institute of Photonic Technology, Jena, Germany
- Friedrich Schiller University Jena, Institute of Applied Optics, Jena, Germany
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Kimchi EY, Burgos-Robles A, Matthews GA, Chakoma T, Patarino M, Weddington JC, Siciliano C, Yang W, Foutch S, Simons R, Fong MF, Jing M, Li Y, Polley DB, Tye KM. Reward contingency gates selective cholinergic suppression of amygdala neurons. eLife 2024; 12:RP89093. [PMID: 38376907 PMCID: PMC10942609 DOI: 10.7554/elife.89093] [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: 02/21/2024] Open
Abstract
Basal forebrain cholinergic neurons modulate how organisms process and respond to environmental stimuli through impacts on arousal, attention, and memory. It is unknown, however, whether basal forebrain cholinergic neurons are directly involved in conditioned behavior, independent of secondary roles in the processing of external stimuli. Using fluorescent imaging, we found that cholinergic neurons are active during behavioral responding for a reward - even prior to reward delivery and in the absence of discrete stimuli. Photostimulation of basal forebrain cholinergic neurons, or their terminals in the basolateral amygdala (BLA), selectively promoted conditioned responding (licking), but not unconditioned behavior nor innate motor outputs. In vivo electrophysiological recordings during cholinergic photostimulation revealed reward-contingency-dependent suppression of BLA neural activity, but not prefrontal cortex. Finally, ex vivo experiments demonstrated that photostimulation of cholinergic terminals suppressed BLA projection neuron activity via monosynaptic muscarinic receptor signaling, while also facilitating firing in BLA GABAergic interneurons. Taken together, we show that the neural and behavioral effects of basal forebrain cholinergic activation are modulated by reward contingency in a target-specific manner.
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Affiliation(s)
- Eyal Y Kimchi
- The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of TechnologyCambridgeUnited States
- Department of Neurology, Northwestern UniversityChicagoUnited States
| | - Anthony Burgos-Robles
- The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of TechnologyCambridgeUnited States
- The Department of Neuroscience, Developmental, and Regenerative Biology, Neuroscience Institute & Brain Health Consortium, University of Texas at San AntonioSan AntonioUnited States
| | - Gillian A Matthews
- The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of TechnologyCambridgeUnited States
| | - Tatenda Chakoma
- The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of TechnologyCambridgeUnited States
| | - Makenzie Patarino
- The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of TechnologyCambridgeUnited States
| | - Javier C Weddington
- The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of TechnologyCambridgeUnited States
| | - Cody Siciliano
- The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of TechnologyCambridgeUnited States
- Vanderbilt Center for Addiction Research, Department of Pharmacology, Vanderbilt UniversityNashvilleUnited States
| | - Wannan Yang
- The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of TechnologyCambridgeUnited States
| | - Shaun Foutch
- The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of TechnologyCambridgeUnited States
| | - Renee Simons
- The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of TechnologyCambridgeUnited States
| | - Ming-fai Fong
- The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of TechnologyCambridgeUnited States
- Coulter Department of Biomedical Engineering, Georgia Tech & Emory UniversityAtlantaUnited States
| | - Miao Jing
- Chinese Institute for Brain ResearchBeijingChina
| | - Yulong Li
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences; PKUIDG/McGovern Institute for Brain Research; Peking-Tsinghua Center for Life SciencesBeijingChina
| | - Daniel B Polley
- Eaton-Peabody Laboratories, Massachusetts Eye and EarBostonUnited States
- Department of Otolaryngology – Head and Neck Surgery, Harvard Medical SchoolBostonUnited States
| | - Kay M Tye
- The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of TechnologyCambridgeUnited States
- HHMI Investigator, Member of the Kavli Institute for Brain and Mind, and Wylie Vale Professor at the Salk Institute for Biological StudiesLa JollaUnited States
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Wang Y, Yang X, Zhang X, Wang Y, Pei W. Implantable intracortical microelectrodes: reviewing the present with a focus on the future. MICROSYSTEMS & NANOENGINEERING 2023; 9:7. [PMID: 36620394 PMCID: PMC9814492 DOI: 10.1038/s41378-022-00451-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Revised: 08/08/2022] [Accepted: 08/22/2022] [Indexed: 06/17/2023]
Abstract
Implantable intracortical microelectrodes can record a neuron's rapidly changing action potentials (spikes). In vivo neural activity recording methods often have either high temporal or spatial resolution, but not both. There is an increasing need to record more neurons over a longer duration in vivo. However, there remain many challenges to overcome before achieving long-term, stable, high-quality recordings and realizing comprehensive, accurate brain activity analysis. Based on the vision of an idealized implantable microelectrode device, the performance requirements for microelectrodes are divided into four aspects, including recording quality, recording stability, recording throughput, and multifunctionality, which are presented in order of importance. The challenges and current possible solutions for implantable microelectrodes are given from the perspective of each aspect. The current developments in microelectrode technology are analyzed and summarized.
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Affiliation(s)
- Yang Wang
- State Key Laboratory of Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, 100083 Beijing, China
- University of Chinese Academy of Sciences, 100049 Beijing, China
| | - Xinze Yang
- State Key Laboratory of Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, 100083 Beijing, China
- University of Chinese Academy of Sciences, 100049 Beijing, China
| | - Xiwen Zhang
- State Key Laboratory of Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, 100083 Beijing, China
- University of Chinese Academy of Sciences, 100049 Beijing, China
| | - Yijun Wang
- State Key Laboratory of Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, 100083 Beijing, China
- University of Chinese Academy of Sciences, 100049 Beijing, China
- Chinese Institute for Brain Research, 102206 Beijing, China
| | - Weihua Pei
- State Key Laboratory of Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, 100083 Beijing, China
- University of Chinese Academy of Sciences, 100049 Beijing, China
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4
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Beacher NJ, Washington KA, Zhang Y, Li Y, Lin DT. GRIN lens applications for studying neurobiology of substance use disorder. ADDICTION NEUROSCIENCE 2022; 4:100049. [PMID: 36531187 PMCID: PMC9757736 DOI: 10.1016/j.addicn.2022.100049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Substance use disorder (SUD) is associated with severe health and social consequences. Continued drug use results in alterations of circuits within the mesolimbic dopamine system. It is critical to observe longitudinal impacts of SUD on neural activity in vivo to identify SUD predispositions, develop pharmaceuticals to prevent overdose, and help people suffering from SUD. However, implicated SUD associated areas are buried in deep brain which makes in vivo observation of neural activity challenging. The gradient index (GRIN) lens can probe these regions in mice and rats. In this short communications review, we will discuss how the GRIN lens can be coupled with other technologies such as miniaturized microscopes, fiberscopes, fMRI, and optogenetics to fully explore in vivo SUD research. Particularly, GRIN lens allows in vivo observation of deep brain regions implicated in SUD, differentiation of genetically distinct neurons, examination of individual cells longitudinally, correlation of neuronal patters with SUD behavior, and manipulation of neural circuits.
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Affiliation(s)
- Nicholas James Beacher
- Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD, United States
| | - Kayden Alecsandre Washington
- Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD, United States
| | - Yan Zhang
- Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD, United States
| | - Yun Li
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY, United States
| | - Da-Ting Lin
- Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD, United States
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Machado TA, Kauvar IV, Deisseroth K. Multiregion neuronal activity: the forest and the trees. Nat Rev Neurosci 2022; 23:683-704. [PMID: 36192596 PMCID: PMC10327445 DOI: 10.1038/s41583-022-00634-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/25/2022] [Indexed: 12/12/2022]
Abstract
The past decade has witnessed remarkable advances in the simultaneous measurement of neuronal activity across many brain regions, enabling fundamentally new explorations of the brain-spanning cellular dynamics that underlie sensation, cognition and action. These recently developed multiregion recording techniques have provided many experimental opportunities, but thoughtful consideration of methodological trade-offs is necessary, especially regarding field of view, temporal acquisition rate and ability to guarantee cellular resolution. When applied in concert with modern optogenetic and computational tools, multiregion recording has already made possible fundamental biological discoveries - in part via the unprecedented ability to perform unbiased neural activity screens for principles of brain function, spanning dozens of brain areas and from local to global scales.
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Affiliation(s)
- Timothy A Machado
- Department of Bioengineering, Stanford University, Stanford, CA, USA
| | - Isaac V Kauvar
- Department of Bioengineering, Stanford University, Stanford, CA, USA
- Department of Electrical Engineering, Stanford University, Stanford, CA, USA
| | - Karl Deisseroth
- Department of Bioengineering, Stanford University, Stanford, CA, USA.
- Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA.
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA.
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Tang J, Xue R, Wang Y, Li M, Jia H, Pakan JMP, Li L, Chen X, Li X. Optical Fiber-Based Recording of Climbing Fiber Ca 2+ Signals in Freely Behaving Mice. BIOLOGY 2022; 11:907. [PMID: 35741428 PMCID: PMC9220032 DOI: 10.3390/biology11060907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 06/09/2022] [Accepted: 06/11/2022] [Indexed: 11/16/2022]
Abstract
The olivocerebellar circuitry is important to convey both motor and non-motor information from the inferior olive (IO) to the cerebellar cortex. Several methods are currently established to observe the dynamics of the olivocerebellar circuitry, largely by recording the complex spike activity of cerebellar Purkinje cells; however, these techniques can be technically challenging to apply in vivo and are not always possible in freely behaving animals. Here, we developed a method for the direct, accessible, and robust recording of climbing fiber (CF) Ca2+ signals based on optical fiber photometry. We first verified the IO stereotactic coordinates and the organization of contralateral CF projections using tracing techniques and then injected Ca2+ indicators optimized for axonal labeling, followed by optical fiber-based recordings. We demonstrated this method by recording CF Ca2+ signals in lobule IV/V of the cerebellar vermis, comparing the resulting signals in freely moving mice. We found various movement-evoked CF Ca2+ signals, but the onset of exploratory-like behaviors, including rearing and tiptoe standing, was highly synchronous with recorded CF activity. Thus, we have successfully established a robust and accessible method to record the CF Ca2+ signals in freely behaving mice, which will extend the toolbox for studying cerebellar function and related disorders.
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Affiliation(s)
- Jiechang Tang
- Center for Neurointelligence, School of Medicine, Chongqing University, Chongqing 400030, China; (J.T.); (R.X.)
- College of Bioengineering, Chongqing University, Chongqing 400044, China
| | - Rou Xue
- Center for Neurointelligence, School of Medicine, Chongqing University, Chongqing 400030, China; (J.T.); (R.X.)
| | - Yan Wang
- Brain Research Instrument Innovation Center, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou 215163, China; (Y.W.); (M.L.); (H.J.)
| | - Min Li
- Brain Research Instrument Innovation Center, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou 215163, China; (Y.W.); (M.L.); (H.J.)
| | - Hongbo Jia
- Brain Research Instrument Innovation Center, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou 215163, China; (Y.W.); (M.L.); (H.J.)
- Combinatorial NeuroImaging Core Facility, Leibniz Institute for Neurobiology, 39118 Magdeburg, Germany
| | - Janelle M. P. Pakan
- Institute of Cognitive Neurology and Dementia Research, Otto-von-Guericke University, 39120 Magdeburg, Germany;
- German Center for Neurodegenerative Diseases (DZNE), 39120 Magdeburg, Germany
| | - Longhui Li
- Center for Neurointelligence, School of Medicine, Chongqing University, Chongqing 400030, China; (J.T.); (R.X.)
| | - Xiaowei Chen
- Brain Research Center and State Key Laboratory of Trauma, Burns, and Combined Injury, Third Military Medical University, Chongqing 400038, China
- Guangyang Bay Laboratory, Chongqing Institute for Brain and Intelligence, Chongqing 400064, China
| | - Xingyi Li
- Center for Neurointelligence, School of Medicine, Chongqing University, Chongqing 400030, China; (J.T.); (R.X.)
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7
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Swanson JL, Chin PS, Romero JM, Srivastava S, Ortiz-Guzman J, Hunt PJ, Arenkiel BR. Advancements in the Quest to Map, Monitor, and Manipulate Neural Circuitry. Front Neural Circuits 2022; 16:886302. [PMID: 35719420 PMCID: PMC9204427 DOI: 10.3389/fncir.2022.886302] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 04/27/2022] [Indexed: 01/27/2023] Open
Abstract
Neural circuits and the cells that comprise them represent the functional units of the brain. Circuits relay and process sensory information, maintain homeostasis, drive behaviors, and facilitate cognitive functions such as learning and memory. Creating a functionally-precise map of the mammalian brain requires anatomically tracing neural circuits, monitoring their activity patterns, and manipulating their activity to infer function. Advancements in cell-type-specific genetic tools allow interrogation of neural circuits with increased precision. This review provides a broad overview of recombination-based and activity-driven genetic targeting approaches, contemporary viral tracing strategies, electrophysiological recording methods, newly developed calcium, and voltage indicators, and neurotransmitter/neuropeptide biosensors currently being used to investigate circuit architecture and function. Finally, it discusses methods for acute or chronic manipulation of neural activity, including genetically-targeted cellular ablation, optogenetics, chemogenetics, and over-expression of ion channels. With this ever-evolving genetic toolbox, scientists are continuing to probe neural circuits with increasing resolution, elucidating the structure and function of the incredibly complex mammalian brain.
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Affiliation(s)
- Jessica L. Swanson
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, TX, United States
| | - Pey-Shyuan Chin
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, TX, United States
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, United States
| | - Juan M. Romero
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, TX, United States
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, United States
- Medical Scientist Training Program, Baylor College of Medicine, Houston, TX, United States
| | - Snigdha Srivastava
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, TX, United States
- Medical Scientist Training Program, Baylor College of Medicine, Houston, TX, United States
| | - Joshua Ortiz-Guzman
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, TX, United States
| | - Patrick J. Hunt
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, TX, United States
- Medical Scientist Training Program, Baylor College of Medicine, Houston, TX, United States
| | - Benjamin R. Arenkiel
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, TX, United States
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, United States
- Medical Scientist Training Program, Baylor College of Medicine, Houston, TX, United States
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Zhao XP, Li H, Dai RP. Neuroimmune crosstalk through brain-derived neurotrophic factor and its precursor pro-BDNF: New insights into mood disorders. World J Psychiatry 2022; 12:379-392. [PMID: 35433323 PMCID: PMC8968497 DOI: 10.5498/wjp.v12.i3.379] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2021] [Revised: 08/22/2021] [Accepted: 01/23/2022] [Indexed: 02/06/2023] Open
Abstract
Mood disorders are the most common mental disorders, affecting approximately 350 million people globally. Recent studies have shown that neuroimmune interaction regulates mood disorders. Brain-derived neurotrophic factor (BDNF) and its precursor pro-BDNF, are involved in the neuroimmune crosstalk during the development of mood disorders. BDNF is implicated in the pathophysiology of psychiatric and neurological disorders especially in antidepressant pharmacotherapy. In this review, we describe the functions of BDNF/pro-BDNF signaling in the central nervous system in the context of mood disorders. In addition, we summarize the developments for BDNF and pro-BDNF functions in mood disorders. This review aims to provide new insights into the impact of neuroimmune interaction on mood disorders and reveal a new basis for further development of diagnostic targets and mood disorders.
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Affiliation(s)
- Xiao-Pei Zhao
- Department of Anesthesiology, The Second Xiangya Hospital, Central South University, Changsha 410011, Hunan Province, China
| | - Hui Li
- Department of Anesthesiology, The Second Xiangya Hospital, Central South University, Changsha 410011, Hunan Province, China
| | - Ru-Ping Dai
- Department of Anesthesiology, The Second Xiangya Hospital, Central South University, Changsha 410011, Hunan Province, China
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Narcisse D, Mustafi SM, Carlson M, Batabyal S, Kim S, Wright W, Kumar Mohanty S. Bioluminescent Multi-Characteristic Opsin for Simultaneous Optical Stimulation and Continuous Monitoring of Cortical Activities. Front Cell Neurosci 2021; 15:750663. [PMID: 34759801 PMCID: PMC8573050 DOI: 10.3389/fncel.2021.750663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Accepted: 09/20/2021] [Indexed: 12/02/2022] Open
Abstract
Stimulation and continuous monitoring of neural activities at cellular resolution are required for the understanding of the sensory processing of stimuli and development of effective neuromodulation therapies. We present bioluminescence multi-characteristic opsin (bMCOII), a hybrid optogenetic actuator, and a bioluminescence Ca2+ sensor for excitation-free, continuous monitoring of neural activities in the visual cortex, with high spatiotemporal resolution. An exceptionally low intensity (10 μW/mm2) of light could elicit neural activation that could be detected by Ca2+ bioluminescence imaging. An uninterrupted (>14 h) recording of visually evoked neural activities in the cortex of mice enabled the determination of strength of sensory activation. Furthermore, an artificial intelligence-based neural activation parameter transformed Ca2+ bioluminescence signals to network activity patterns. During continuous Ca2+-bioluminescence recordings, visual cortical activity peaked at the seventh to eighth hour of anesthesia, coinciding with circadian rhythm. For both direct optogenetic stimulation in cortical slices and visually evoked activities in the visual cortex, we observed secondary delayed Ca2+-bioluminescence responses, suggesting the involvement of neuron-astrocyte-neuron pathway. Our approach will enable the development of a modular and scalable interface system capable of serving a multiplicity of applications to modulate and monitor large-scale activities in the brain.
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Montinaro C, Pisanello M, Bianco M, Spagnolo B, Pisano F, Balena A, De Nuccio F, Lofrumento DD, Verri T, De Vittorio M, Pisanello F. Influence of the anatomical features of different brain regions on the spatial localization of fiber photometry signals. BIOMEDICAL OPTICS EXPRESS 2021; 12:6081-6094. [PMID: 34745723 PMCID: PMC8547979 DOI: 10.1364/boe.439848] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 08/25/2021] [Accepted: 08/25/2021] [Indexed: 05/30/2023]
Abstract
Fiber photometry is widely used in neuroscience labs for in vivo detection of functional fluorescence from optical indicators of neuronal activity with a simple optical fiber. The fiber is commonly placed next to the region of interest to both excite and collect the fluorescence signal. However, the path of both excitation and fluorescence photons is altered by the uneven optical properties of the brain, due to local variation of the refractive index, different cellular types, densities and shapes. Nonetheless, the effect of the local anatomy on the actual shape and extent of the volume of tissue that interfaces with the fiber has received little attention so far. To fill this gap, we measured the size and shape of fiber photometry efficiency field in the primary motor and somatosensory cortex, in the hippocampus and in the striatum of the mouse brain, highlighting how their substructures determine the detected signal and the depth at which photons can be mined. Importantly, we show that the information on the spatial expression of the fluorescent probes alone is not sufficient to account for the contribution of local subregions to the overall collected signal, and it must be combined with the optical properties of the tissue adjacent to the fiber tip.
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Affiliation(s)
- Cinzia Montinaro
- Istituto Italiano di Tecnologia (IIT), Center for Biomolecular Nanotechnologies, Via Barsanti 14, 73010 Arnesano (Lecce), Italy
- Dipartimento di Scienze e Tecnologie Biologiche e Ambientali, Università del Salento, Via per Monteroni, 73100 Lecce, Italy
| | - Marco Pisanello
- Istituto Italiano di Tecnologia (IIT), Center for Biomolecular Nanotechnologies, Via Barsanti 14, 73010 Arnesano (Lecce), Italy
| | - Marco Bianco
- Istituto Italiano di Tecnologia (IIT), Center for Biomolecular Nanotechnologies, Via Barsanti 14, 73010 Arnesano (Lecce), Italy
- Dipartimento di Ingegneria dell'Innovazione, Università del Salento, Via per Monteroni, 73100 Lecce, Italy
| | - Barbara Spagnolo
- Istituto Italiano di Tecnologia (IIT), Center for Biomolecular Nanotechnologies, Via Barsanti 14, 73010 Arnesano (Lecce), Italy
| | - Filippo Pisano
- Istituto Italiano di Tecnologia (IIT), Center for Biomolecular Nanotechnologies, Via Barsanti 14, 73010 Arnesano (Lecce), Italy
| | - Antonio Balena
- Istituto Italiano di Tecnologia (IIT), Center for Biomolecular Nanotechnologies, Via Barsanti 14, 73010 Arnesano (Lecce), Italy
| | - Francesco De Nuccio
- Dipartimento di Scienze e Tecnologie Biologiche e Ambientali, Università del Salento, Via per Monteroni, 73100 Lecce, Italy
| | - Dario Domenico Lofrumento
- Dipartimento di Scienze e Tecnologie Biologiche e Ambientali, Università del Salento, Via per Monteroni, 73100 Lecce, Italy
| | - Tiziano Verri
- Dipartimento di Scienze e Tecnologie Biologiche e Ambientali, Università del Salento, Via per Monteroni, 73100 Lecce, Italy
| | - Massimo De Vittorio
- Istituto Italiano di Tecnologia (IIT), Center for Biomolecular Nanotechnologies, Via Barsanti 14, 73010 Arnesano (Lecce), Italy
- Dipartimento di Ingegneria dell'Innovazione, Università del Salento, Via per Monteroni, 73100 Lecce, Italy
- Equally contributing authors
| | - Ferruccio Pisanello
- Istituto Italiano di Tecnologia (IIT), Center for Biomolecular Nanotechnologies, Via Barsanti 14, 73010 Arnesano (Lecce), Italy
- Equally contributing authors
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Jones-Tabah J, Mohammad H, Clarke PBS, Hébert TE. In vivo detection of GPCR-dependent signaling using fiber photometry and FRET-based biosensors. Methods 2021; 203:422-430. [PMID: 34022351 DOI: 10.1016/j.ymeth.2021.05.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 05/03/2021] [Accepted: 05/11/2021] [Indexed: 12/27/2022] Open
Abstract
Genetically encoded fluorescent biosensors allow intracellular signaling dynamics to be tracked in live cells and tissues using optical detection. Many such biosensors are based on the principle of Förster resonance energy transfer (FRET), and we have recently developed a simple approach for in vivo detection of FRET-based biosensor signals using fiber photometry. By combining fiber photometry with FRET-based biosensors, we were able to track GPCR-dependent signaling pathways over time, and in response to drug treatments in freely-moving adult rats. Recording from specific neuronal populations, we can quantify intracellular signaling while simultaneously measuring behavioral responses. Our approach, described in detail here, uses adeno-associated viruses infused intracerebrally in order to express genetically-encoded FRET-based biosensors. After several weeks to allow biosensor expression, fiber photometry is used in order to record drug responses in real time from freely-moving adult rats. This methodology would be compatible with other mammalian species and with many biosensors. Hence, it has wide applicability across a spectrum of neuroscience research, ranging from the study of neural circuits and behavior, to preclinical drug development and screening.
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Affiliation(s)
- Jace Jones-Tabah
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec H3G 1Y6, Canada
| | - Hanan Mohammad
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec H3G 1Y6, Canada
| | - Paul B S Clarke
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec H3G 1Y6, Canada.
| | - Terence E Hébert
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec H3G 1Y6, Canada.
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12
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Calvo-Rodriguez M, Kharitonova EK, Bacskai BJ. In vivo brain imaging of mitochondrial Ca 2+ in neurodegenerative diseases with multiphoton microscopy. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2021; 1868:118998. [PMID: 33684410 PMCID: PMC8057769 DOI: 10.1016/j.bbamcr.2021.118998] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Accepted: 02/22/2021] [Indexed: 10/22/2022]
Abstract
Mitochondria are involved in a large number of essential roles related to neuronal function. Ca2+ handling by mitochondria is critical for many of these functions, including energy production and cellular fate. Conversely, mitochondrial Ca2+ mishandling has been related to a variety of neurodegenerative diseases. Investigating mitochondrial Ca2+ dynamics is essential for advancing our understanding of the role of intracellular mitochondrial Ca2+ signals in physiology and pathology. Improved Ca2+ indicators, and the ability to target them to different cells and compartments, have emerged as useful tools for analysis of Ca2+ signals in living organisms. Combined with state-of-the-art techniques such as multiphoton microscopy, they allow for the study of mitochondrial Ca2+ dynamics in vivo in mouse models of the disease. Here, we provide an overview of the Ca2+ transporters/ion channels in mitochondrial membranes, and the involvement of mitochondrial Ca2+ in neurodegenerative diseases followed by a summary of the main tools available to evaluate mitochondrial Ca2+ dynamics in vivo using the aforementioned technique.
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Affiliation(s)
- Maria Calvo-Rodriguez
- Alzheimer Research Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, 114, 16th St, Charlestown, MA, 02129, USA.
| | - Elizabeth K Kharitonova
- Alzheimer Research Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, 114, 16th St, Charlestown, MA, 02129, USA
| | - Brian J Bacskai
- Alzheimer Research Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, 114, 16th St, Charlestown, MA, 02129, USA
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13
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Bi X, Beck C, Gong Y. Genetically Encoded Fluorescent Indicators for Imaging Brain Chemistry. BIOSENSORS 2021; 11:116. [PMID: 33920418 PMCID: PMC8069469 DOI: 10.3390/bios11040116] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 04/06/2021] [Accepted: 04/09/2021] [Indexed: 12/17/2022]
Abstract
Genetically encoded fluorescent indicators, combined with optical imaging, enable the detection of physiologically or behaviorally relevant neural activity with high spatiotemporal resolution. Recent developments in protein engineering and screening strategies have improved the dynamic range, kinetics, and spectral properties of genetically encoded fluorescence indicators of brain chemistry. Such indicators have detected neurotransmitter and calcium dynamics with high signal-to-noise ratio at multiple temporal and spatial scales in vitro and in vivo. This review summarizes the current trends in these genetically encoded fluorescent indicators of neurotransmitters and calcium, focusing on their key metrics and in vivo applications.
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Affiliation(s)
| | | | - Yiyang Gong
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA; (X.B.); (C.B.)
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14
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Multimode Optical Fibers for Optical Neural Interfaces. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021. [PMID: 33398843 DOI: 10.1007/978-981-15-8763-4_40] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register]
Abstract
Although multiphoton microscopy enables optical control and monitoring of neural activity with single cells resolution over a depth of several hundreds of micrometers, the scattering nature of the brain tissue requires implantable optical neural interfaces to access subcortical structures. If micro light-emitting devices (μLEDs) and solid-state waveguides represent important technological advancements for the field, multimodal optical fibers (MMFs) are still the most diffused tool in neuroscience labs to interface with deep regions of the brain. At a first glance, MMFs can be seen as very limited systems. However, new studies and discoveries in optics, photonics, and technological solutions for their application to neuroscience research have enabled applications of MMF where competing technologies fail. In this framework, the chapter starts with a description of optical neural interfaces based on MMF, with specific reference on recent works analyzing the performances of this approach to deliver and collect light from scattering tissue. The discussion then focuses on how peculiar features of MMFs can be exploited to obtain unconventional applications, including brain imaging through a single multimode fiber, multifunctional neural interfaces, and depth-resolved light delivery and functional fluorescence collection.
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15
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Ineichen C, Greter A, Baer M, Sigrist H, Sautter E, Sych Y, Helmchen F, Pryce CR. Basomedial amygdala activity in mice reflects specific and general aversion uncontrollability. Eur J Neurosci 2020; 55:2435-2454. [PMID: 33338290 PMCID: PMC9292353 DOI: 10.1111/ejn.15090] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 12/10/2020] [Accepted: 12/14/2020] [Indexed: 02/06/2023]
Abstract
Learning adaptive behaviour to control aversion is a major brain function. Detecting the absence of control is also important, although chronic uncontrollable aversion can impact maladaptively on stimulus processing in general. The mouse basomedial amygdala (BMA) contributes to aversion processing with high BMA activity associated with active behavioural responding. The overall aim of the present study was to investigate the associations between aversion (un)controllability, BMA activity and behaviour. Fibre photometry of GCaMP6‐expressing BMA neuron populations was applied in freely behaving adult male mice during exposure to mild electrical shocks, and effects of specific or general (un)controllability were investigated. In a discrete learned helplessness (LH) effect paradigm, mice underwent discrete sessions of pre‐exposure to either escapable shock (ES) or inescapable shock (IES) followed by an escape test. IES mice acquired fewer escape attempts than ES mice, and this co‐occurred with higher aversion‐related BMA activity in the IES group. After 30 days, ES and IES mice were allocated equally to either chronic social stress (CSS)—exposure to continuous uncontrollable social aversion—or control handling (CON), and on days 5 and 15 underwent an IES session. CSS mice made fewer escape attempts than CON mice, and this was now associated with lower aversion‐related BMA activity in the CSS group. These findings suggest that mouse BMA activity is higher when discrete aversion is uncontrollable but becomes lower following chronic uncontrollable aversion exposure. Therefore, BMA activity could be a neural marker of adaptive and maladaptive states consequent to specific and general uncontrollability, respectively.
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Affiliation(s)
- Christian Ineichen
- Preclinical Laboratory for Translational Research into Affective Disorders (PLaTRAD), Department of Psychiatry, Psychotherapy and Psychosomatics, University of Zurich, Zurich, Switzerland
| | - Alexandra Greter
- Preclinical Laboratory for Translational Research into Affective Disorders (PLaTRAD), Department of Psychiatry, Psychotherapy and Psychosomatics, University of Zurich, Zurich, Switzerland
| | - Mischa Baer
- Preclinical Laboratory for Translational Research into Affective Disorders (PLaTRAD), Department of Psychiatry, Psychotherapy and Psychosomatics, University of Zurich, Zurich, Switzerland
| | - Hannes Sigrist
- Preclinical Laboratory for Translational Research into Affective Disorders (PLaTRAD), Department of Psychiatry, Psychotherapy and Psychosomatics, University of Zurich, Zurich, Switzerland
| | | | - Yaroslav Sych
- Brain Research Institute, University of Zurich, Zurich, Switzerland
| | - Fritjof Helmchen
- Brain Research Institute, University of Zurich, Zurich, Switzerland.,Neuroscience Center Zurich, Zurich, Switzerland
| | - Christopher R Pryce
- Preclinical Laboratory for Translational Research into Affective Disorders (PLaTRAD), Department of Psychiatry, Psychotherapy and Psychosomatics, University of Zurich, Zurich, Switzerland.,Neuroscience Center Zurich, Zurich, Switzerland
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16
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Abstract
Thirst is a highly potent drive that motivates organisms to seek out and consume balance-restoring stimuli. The detection of dehydration is well understood and involves signals of peripheral origin and the sampling of internal milieu by first order homeostatic neurons within the lamina terminalis-particularly glutamatergic neurons of the subfornical organ expressing CaMKIIa (SFOCaMKIIa). However, it remains unknown whether mesolimbic dopamine pathways that are critical for motivation and reinforcement integrate information from these "early" dehydration signals. We used in vivo fiber photometry in the ventral tegmental area and measured phasic dopamine responses to a water-predictive cue. Thirst, but not hunger, potentiated the phasic dopamine response to the water cue. In euvolemic rats, the dipsogenic hormone angiotensin II, but not the orexigenic hormone ghrelin, potentiated the dopamine response similarly to that observed in water-deprived rats. Chemogenetic manipulations of SFOCaMKIIa revealed bidirectional control of phasic dopamine signaling during cued water reward. Taking advantage of within-subject designs, we found predictive relationships between changes in cue-evoked dopamine response and changes in behavioral responses-supporting a role for dopamine in motivation induced by homeostatic need. Collectively, we reveal a putative mechanism for the invigoration of goal-directed behavior: internal milieu communicates to first order, need state-selective circuits to potentiate the mesolimbic dopamine system's response to cues predictive of restorative stimuli.
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17
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Azimi Z, Barzan R, Spoida K, Surdin T, Wollenweber P, Mark MD, Herlitze S, Jancke D. Separable gain control of ongoing and evoked activity in the visual cortex by serotonergic input. eLife 2020; 9:e53552. [PMID: 32252889 PMCID: PMC7138610 DOI: 10.7554/elife.53552] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Accepted: 03/04/2020] [Indexed: 01/25/2023] Open
Abstract
Controlling gain of cortical activity is essential to modulate weights between internal ongoing communication and external sensory drive. Here, we show that serotonergic input has separable suppressive effects on the gain of ongoing and evoked visual activity. We combined optogenetic stimulation of the dorsal raphe nucleus (DRN) with wide-field calcium imaging, extracellular recordings, and iontophoresis of serotonin (5-HT) receptor antagonists in the mouse visual cortex. 5-HT1A receptors promote divisive suppression of spontaneous activity, while 5-HT2A receptors act divisively on visual response gain and largely account for normalization of population responses over a range of visual contrasts in awake and anesthetized states. Thus, 5-HT input provides balanced but distinct suppressive effects on ongoing and evoked activity components across neuronal populations. Imbalanced 5-HT1A/2A activation, either through receptor-specific drug intake, genetically predisposed irregular 5-HT receptor density, or change in sensory bombardment may enhance internal broadcasts and reduce sensory drive and vice versa.
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Affiliation(s)
- Zohre Azimi
- Optical Imaging Group, Institut für Neuroinformatik, Ruhr University BochumBochumGermany
- International Graduate School of Neuroscience (IGSN), Ruhr University BochumBochumGermany
| | - Ruxandra Barzan
- Optical Imaging Group, Institut für Neuroinformatik, Ruhr University BochumBochumGermany
- International Graduate School of Neuroscience (IGSN), Ruhr University BochumBochumGermany
| | - Katharina Spoida
- Department of General Zoology and Neurobiology, Ruhr University BochumBochumGermany
| | - Tatjana Surdin
- Department of General Zoology and Neurobiology, Ruhr University BochumBochumGermany
| | - Patric Wollenweber
- Department of General Zoology and Neurobiology, Ruhr University BochumBochumGermany
| | - Melanie D Mark
- Department of General Zoology and Neurobiology, Ruhr University BochumBochumGermany
| | - Stefan Herlitze
- Department of General Zoology and Neurobiology, Ruhr University BochumBochumGermany
| | - Dirk Jancke
- Optical Imaging Group, Institut für Neuroinformatik, Ruhr University BochumBochumGermany
- International Graduate School of Neuroscience (IGSN), Ruhr University BochumBochumGermany
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18
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Patel AA, McAlinden N, Mathieson K, Sakata S. Simultaneous Electrophysiology and Fiber Photometry in Freely Behaving Mice. Front Neurosci 2020; 14:148. [PMID: 32153363 PMCID: PMC7047771 DOI: 10.3389/fnins.2020.00148] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 02/07/2020] [Indexed: 12/27/2022] Open
Abstract
In vivo electrophysiology is the gold standard technique used to investigate sub-second neural dynamics in freely behaving animals. However, monitoring cell-type-specific population activity is not a trivial task. Over the last decade, fiber photometry based on genetically encoded calcium indicators (GECIs) has been widely adopted as a versatile tool to monitor cell-type-specific population activity in vivo. However, this approach suffers from low temporal resolution. Here, we combine these two approaches to monitor both sub-second field potentials and cell-type-specific population activity in freely behaving mice. By developing an economical custom-made system and constructing a hybrid implant of an electrode and a fiber optic cannula, we simultaneously monitor artifact-free mesopontine field potentials and calcium transients in cholinergic neurons across the sleep-wake cycle. We find that mesopontine cholinergic activity co-occurs with sub-second pontine waves, called P-waves, during rapid eye movement sleep. Given the simplicity of our approach, simultaneous electrophysiological recording and cell-type-specific imaging provides a novel and valuable tool for interrogating state-dependent neural circuit dynamics in vivo.
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Affiliation(s)
- Amisha A Patel
- Strathclyde Institute of Pharmacy & Biomedical Sciences, University of Strathclyde, Glasgow, United Kingdom
| | - Niall McAlinden
- Department of Physics, Institute of Photonics, SUPA, University of Strathclyde, Glasgow, United Kingdom
| | - Keith Mathieson
- Department of Physics, Institute of Photonics, SUPA, University of Strathclyde, Glasgow, United Kingdom
| | - Shuzo Sakata
- Strathclyde Institute of Pharmacy & Biomedical Sciences, University of Strathclyde, Glasgow, United Kingdom
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19
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Cichon J, Magrané J, Shtridler E, Chen C, Sun L, Yang G, Gan WB. Imaging neuronal activity in the central and peripheral nervous systems using new Thy1.2-GCaMP6 transgenic mouse lines. J Neurosci Methods 2020; 334:108535. [PMID: 31972184 PMCID: PMC7369242 DOI: 10.1016/j.jneumeth.2019.108535] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 11/28/2019] [Accepted: 11/28/2019] [Indexed: 12/14/2022]
Abstract
BACKGROUND The genetically encoded calcium (Ca2+) sensor GCaMP6 has been widely used for imaging Ca2+ transients in neuronal somata, dendrites, and synapses. NEW METHOD Here we describe five new transgenic mouse lines expressing GCaMP6F (fast) or GCaMP6S (slow) in the central and peripheral nervous system under the control of theThy1.2 promoter. RESULTS These transgenic lines exhibit stable and layer-specific expression of GCaMP6 in multiple brain regions. They have several unique features compared to existing Thy1.2-GCaMP6 mice, including sparse expression of GCaMP6 in layer V pyramidal neurons of the cerebral cortex, motor neurons in the spinal cord, as well as sensory neurons in dorsal root ganglia (DRG). We further demonstrate that these mouse lines allow for robust detection of Ca2+ transients in neuronal somata and apical dendrites in the cerebral cortex of both anesthetized and awake behaving mice, as well as in DRG neurons. COMPARISON WITH EXISTING METHOD(S) These transgenic lines allows Ca2+ imaging of dendrites and somas of pyramidal neurons in specific cortical layers that is difficult to achieve with existing methods. CONCLUSIONS These GCaMP6 transgenic lines thus provide useful tools for functional analysis of neuronal circuits in both central and peripheral nervous systems.
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Affiliation(s)
- Joseph Cichon
- Department of Anesthesiology and Critical Care, Penn Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Jordi Magrané
- Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY, USA
| | - Elina Shtridler
- Molecular Neurobiology Program, Skirball Institute, Department of Physiology and Neuroscience, New York University School of Medicine, New York, NY, USA
| | - Chao Chen
- Molecular Neurobiology Program, Skirball Institute, Department of Physiology and Neuroscience, New York University School of Medicine, New York, NY, USA
| | - Linlin Sun
- Department of Anesthesiology, Columbia University Medical Center, New York, NY, USA
| | - Guang Yang
- Department of Anesthesiology, Columbia University Medical Center, New York, NY, USA
| | - Wen-Biao Gan
- Molecular Neurobiology Program, Skirball Institute, Department of Physiology and Neuroscience, New York University School of Medicine, New York, NY, USA; Department of Anesthesiology, New York University School of Medicine, New York, NY, USA.
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20
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Konanur VR, Hsu TM, Kanoski SE, Hayes MR, Roitman MF. Phasic dopamine responses to a food-predictive cue are suppressed by the glucagon-like peptide-1 receptor agonist Exendin-4. Physiol Behav 2019; 215:112771. [PMID: 31821815 DOI: 10.1016/j.physbeh.2019.112771] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 12/06/2019] [Accepted: 12/06/2019] [Indexed: 12/21/2022]
Abstract
Phasic dopamine activity is evoked by reliable predictors of food reward and plays a role in cue-triggered, goal-directed behavior. While this important signal is modulated by physiological state (e.g. hunger, satiety), the mechanisms by which physiological state is integrated by dopamine neurons is only beginning to be elucidated. Activation of central receptors for glucagon-like peptide-1 (GLP-1R) via long-acting agonists (e.g., Exendin-4) suppresses food intake and food-directed motivated behavior, in part, through action in regions with dopamine cell bodies, terminals, and/or neural populations that directly target the mesolimbic dopamine system. However, the effects of GLP-1R activation on cue-evoked, phasic dopamine signaling remain unknown. Here, in vivo fiber photometry was used to capture real-time signaling dynamics selectively from dopamine neurons in the ventral tegmental area of male and female transgenic (tyrosine hydroxylase-Cre; TH:Cre+) rats trained to associate an audio cue with the brief availability of a sucrose solution. Cue presentation evoked a brief spike in dopamine activity. Administration of Exendin-4 (Ex4; 0, 0.05, 0.1 μg) to the lateral ventricle both dose-dependently suppressed sucrose-directed behaviors and the magnitude of cue-evoked dopamine activity. Moreover, the amplitude of cue evoked dopamine activity was significantly correlated with subsequent sucrose-directed behaviors. While female rats exhibited overall reduced dopamine responses to the sucrose-paired cue relative to males, there was no significant interaction with Ex4. Together, these findings support a role for central GLP-1Rs in modulating a form of dopamine signaling that influences approach behavior and provide a potential mechanism whereby GLP-1 suppresses food-directed behaviors.
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Affiliation(s)
- Vaibhav R Konanur
- Graduate Program in Neuroscience, University of Illinois at Chicago, Chicago, IL, United States
| | - Ted M Hsu
- Department of Psychology, University of Illinois at Chicago, 1007W. Harrison St., Chicago, IL 60607-7137, United States
| | - Scott E Kanoski
- Department of Biological Sciences, Human and Evolutionary Biology Section, University of Southern California, Los Angeles, CA, United States
| | - Matthew R Hayes
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Mitchell F Roitman
- Department of Psychology, University of Illinois at Chicago, 1007W. Harrison St., Chicago, IL 60607-7137, United States.
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21
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Depth-resolved fiber photometry with a single tapered optical fiber implant. Nat Methods 2019; 16:1185-1192. [PMID: 31591577 DOI: 10.1038/s41592-019-0581-x] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 08/22/2019] [Indexed: 11/08/2022]
Abstract
Fiber photometry is increasingly utilized to monitor fluorescent sensors of neural activity in the brain. However, most implementations are based on flat-cleaved optical fibers that can only interface with shallow tissue volumes adjacent to the fiber. We exploit modal properties of tapered optical fibers (TFs) to enable light collection over an extent of up to 2 mm of tissue and multisite photometry along the taper. Using a single TF, we simultaneously observed distinct dopamine transients in dorsal and ventral striatum in freely moving mice performing a simple, operant conditioning task. Collection volumes from TFs can also be engineered in both shape and size by microstructuring the nonplanar surface of the taper, to optically target multiple sites not only in the deep brain but, in general, in any biological system or organ in which light collection is beneficial but challenging because of light scattering and absorption.
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22
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Sych Y, Chernysheva M, Sumanovski LT, Helmchen F. High-density multi-fiber photometry for studying large-scale brain circuit dynamics. Nat Methods 2019; 16:553-560. [PMID: 31086339 DOI: 10.1038/s41592-019-0400-4] [Citation(s) in RCA: 115] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 03/28/2019] [Indexed: 11/09/2022]
Abstract
Animal behavior originates from neuronal activity distributed across brain-wide networks. However, techniques available to assess large-scale neural dynamics in behaving animals remain limited. Here we present compact, chronically implantable, high-density arrays of optical fibers that enable multi-fiber photometry and optogenetic perturbations across many regions in the mammalian brain. In mice engaged in a texture discrimination task, we achieved simultaneous photometric calcium recordings from networks of 12-48 brain regions, including striatal, thalamic, hippocampal and cortical areas. Furthermore, we optically perturbed subsets of regions in VGAT-ChR2 mice by targeting specific fiber channels with a spatial light modulator. Perturbation of ventral thalamic nuclei caused distributed network modulation and behavioral deficits. Finally, we demonstrate multi-fiber photometry in freely moving animals, including simultaneous recordings from two mice during social interaction. High-density multi-fiber arrays are versatile tools for the investigation of large-scale brain dynamics during behavior.
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Affiliation(s)
- Yaroslav Sych
- Brain Research Institute, University of Zurich, Zurich, Switzerland.
| | - Maria Chernysheva
- Brain Research Institute, University of Zurich, Zurich, Switzerland.,Neuroscience Center Zurich, Zurich, Switzerland
| | | | - Fritjof Helmchen
- Brain Research Institute, University of Zurich, Zurich, Switzerland. .,Neuroscience Center Zurich, Zurich, Switzerland.
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23
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Stereotypical patterns of epileptiform calcium signal in hippocampal CA1, CA3, dentate gyrus and entorhinal cortex in freely moving mice. Sci Rep 2019; 9:4518. [PMID: 30872744 PMCID: PMC6418290 DOI: 10.1038/s41598-019-41241-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Accepted: 03/04/2019] [Indexed: 11/08/2022] Open
Abstract
Epilepsy is a multi-etiological brain dysfunction syndrome. Hippocampal neuronal damage induced by seizures may be one of the causes leading to cognitive impairment, but the underlying mechanism remains to be further elucidated. The kainic acid (KA) model of temporal lobe epilepsy is widely used in understanding of the epileptogenesis. Fiber photometry is a signal detection technology suitable for recording calcium activity of neurons in the deep brain of freely moving animal. Here, we used the optical fiber-based method to monitor the real-time neuronal population activities of freely moving mice after subcutaneous injection of KA. We observed that KA administration led to one to three kinds of stereotypical patterns of epileptiform calcium activity in CA1, CA3, and dentate gyrus (DG) of the hippocampus, as well as the entorhinal cortex (EC). There were three kinds of waves in the hippocampal CA1, which we named wave 1, wave 2 and slow flash. Wave 1 and wave 2 appeared in both the CA3 and DG regions, but the EC only showed wave 1. In these epileptiform calcium signals, we observed a high amplitude and long duration calcium wave as a part of wave 2, which resembled cortical spreading depression (CSD) and always appeared at or after the end of seizure. Because the same characteristic of epileptiform calcium signal appeared in different brain regions, calcium signal may not exist with region specificity, but may exhibit a cell type specific manner. Thus, our work provides a support for the pathogenesis of epilepsy and epileptiform signal transmission research.
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24
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Pisanello M, Pisano F, Hyun M, Maglie E, Balena A, De Vittorio M, Sabatini BL, Pisanello F. The Three-Dimensional Signal Collection Field for Fiber Photometry in Brain Tissue. Front Neurosci 2019; 13:82. [PMID: 30863275 PMCID: PMC6399578 DOI: 10.3389/fnins.2019.00082] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2018] [Accepted: 01/25/2019] [Indexed: 12/15/2022] Open
Abstract
Fiber photometry is used to monitor signals from fluorescent indicators in genetically-defined neural populations in behaving animals. Recently, fiber photometry has rapidly expanded and it now provides researchers with increasingly powerful means to record neural dynamics and neuromodulatory action. However, it is not clear how to select the optimal fiber optic given the constraints and goals of a particular experiment. Here, using combined confocal/2-photon microscope, we quantitatively characterize the fluorescence collection properties of various optical fibers in brain tissue. We show that the fiber size plays a major role in defining the volume of the optically sampled brain region, whereas numerical aperture impacts the total amount of collected signal and, marginally, the shape and size of the collection volume. We show that ~80% of the effective signal arises from 105 to 106 μm3 volume extending ~200 μm from the fiber facet for 200 μm core optical fibers. Together with analytical and ray tracing collection maps, our results reveal the light collection properties of different optical fibers in brain tissue, allowing for an accurate selection of the fibers for photometry and helping for a more precise interpretation of measurements in terms of sampled volume.
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Affiliation(s)
- Marco Pisanello
- Istituto Italiano di Tecnologia, Center for Biomolecular Nanotechnologies, Lecce, Italy
| | - Filippo Pisano
- Istituto Italiano di Tecnologia, Center for Biomolecular Nanotechnologies, Lecce, Italy
| | - Minsuk Hyun
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA, United States
| | - Emanuela Maglie
- Istituto Italiano di Tecnologia, Center for Biomolecular Nanotechnologies, Lecce, Italy
- Dipartimento di Ingeneria dell'Innovazione, Università del Salento, Lecce, Italy
| | - Antonio Balena
- Istituto Italiano di Tecnologia, Center for Biomolecular Nanotechnologies, Lecce, Italy
- Dipartimento di Ingeneria dell'Innovazione, Università del Salento, Lecce, Italy
| | - Massimo De Vittorio
- Istituto Italiano di Tecnologia, Center for Biomolecular Nanotechnologies, Lecce, Italy
- Dipartimento di Ingeneria dell'Innovazione, Università del Salento, Lecce, Italy
| | - Bernardo L. Sabatini
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA, United States
| | - Ferruccio Pisanello
- Istituto Italiano di Tecnologia, Center for Biomolecular Nanotechnologies, Lecce, Italy
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25
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Keller GB, Mrsic-Flogel TD. Predictive Processing: A Canonical Cortical Computation. Neuron 2018; 100:424-435. [PMID: 30359606 PMCID: PMC6400266 DOI: 10.1016/j.neuron.2018.10.003] [Citation(s) in RCA: 325] [Impact Index Per Article: 54.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 09/07/2018] [Accepted: 10/01/2018] [Indexed: 01/15/2023]
Abstract
This perspective describes predictive processing as a computational framework for understanding cortical function in the context of emerging evidence, with a focus on sensory processing. We discuss how the predictive processing framework may be implemented at the level of cortical circuits and how its implementation could be falsified experimentally. Lastly, we summarize the general implications of predictive processing on cortical function in healthy and diseased states.
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Affiliation(s)
- Georg B Keller
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland; Faculty of Natural Sciences, University of Basel, Basel, Switzerland.
| | - Thomas D Mrsic-Flogel
- Sainsbury Wellcome Centre for Neural Circuits and Behaviour, University College London, London, UK
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26
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Schlegel F, Sych Y, Schroeter A, Stobart J, Weber B, Helmchen F, Rudin M. Fiber-optic implant for simultaneous fluorescence-based calcium recordings and BOLD fMRI in mice. Nat Protoc 2018; 13:840-855. [PMID: 29599439 DOI: 10.1038/nprot.2018.003] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Despite the growing popularity of blood oxygen level-dependent (BOLD) functional MRI (fMRI), understanding of its underlying principles is still limited. This protocol describes a technique for simultaneous measurement of neural activity using fluorescent calcium indicators together with the corresponding hemodynamic BOLD fMRI response in the mouse brain. Our early work using small-molecule fluorophores in rats gave encouraging results but was limited to acute measurements using synthetic dyes. Our latest procedure combines fMRI with optical detection of cell-type-specific virally delivered GCaMP6, a genetically encoded calcium indicator (GECI). GCaMP6 fluorescence, which increases upon calcium binding, is collected by a chronically implanted optical fiber, allowing longitudinal studies in mice. The chronic implant, placed horizontally on the skull, has an angulated tip that reflects light into the brain and is connected via fiber optics to a remote optical setup. The technique allows access to the neocortex and does not require adaptations of commercial MRI hardware. The hybrid approach permits fiber-optic calcium recordings with simultaneous artifact-free BOLD fMRI with full brain coverage and 1-s temporal resolution using standard gradient-echo echo-planar imaging (GE-EPI) sequences. The method provides robust, cell-type-specific readouts to link neural activity to BOLD signals, as emonstrated for task-free ('resting-state') conditions and in response to hind-paw stimulation. These results highlight the power of fiber photometry combined with fMRI, which we aim to further advance in this protocol. The approach can be easily adapted to study other molecular processes using suitable fluorescent indicators.
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Affiliation(s)
- Felix Schlegel
- Institute for Biomedical Engineering, University of Zurich and ETH Zurich, Zurich, Switzerland.,Neuroscience Center Zurich, University of Zurich and ETH Zurich, Zurich, Switzerland
| | - Yaroslav Sych
- Laboratory of Neural Circuit Dynamics, Brain Research Institute, University of Zurich, Zurich, Switzerland
| | - Aileen Schroeter
- Institute for Biomedical Engineering, University of Zurich and ETH Zurich, Zurich, Switzerland
| | - Jillian Stobart
- Neuroscience Center Zurich, University of Zurich and ETH Zurich, Zurich, Switzerland.,Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
| | - Bruno Weber
- Neuroscience Center Zurich, University of Zurich and ETH Zurich, Zurich, Switzerland.,Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
| | - Fritjof Helmchen
- Neuroscience Center Zurich, University of Zurich and ETH Zurich, Zurich, Switzerland.,Laboratory of Neural Circuit Dynamics, Brain Research Institute, University of Zurich, Zurich, Switzerland
| | - Markus Rudin
- Institute for Biomedical Engineering, University of Zurich and ETH Zurich, Zurich, Switzerland.,Neuroscience Center Zurich, University of Zurich and ETH Zurich, Zurich, Switzerland.,Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
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27
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Brain-state dependent astrocytic Ca 2+ signals are coupled to both positive and negative BOLD-fMRI signals. Proc Natl Acad Sci U S A 2018; 115:E1647-E1656. [PMID: 29382752 DOI: 10.1073/pnas.1711692115] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Astrocytic Ca2+-mediated gliovascular interactions regulate the neurovascular network in situ and in vivo. However, it is difficult to measure directly both the astrocytic activity and fMRI to relate the various forms of blood-oxygen-level-dependent (BOLD) signaling to brain states under normal and pathological conditions. In this study, fMRI and GCaMP-mediated Ca2+ optical fiber recordings revealed distinct evoked astrocytic Ca2+ signals that were coupled with positive BOLD signals and intrinsic astrocytic Ca2+ signals that were coupled with negative BOLD signals. Both evoked and intrinsic astrocytic calcium signal could occur concurrently or respectively during stimulation. The intrinsic astrocytic calcium signal can be detected globally in multiple cortical sites in contrast to the evoked astrocytic calcium signal only detected at the activated cortical region. Unlike propagating Ca2+ waves in spreading depolarization/depression, the intrinsic Ca2+ spikes occurred simultaneously in both hemispheres and were initiated upon the activation of the central thalamus and midbrain reticular formation. The occurrence of the intrinsic astrocytic calcium signal is strongly coincident with an increased EEG power level of the brain resting-state fluctuation. These results demonstrate highly correlated astrocytic Ca2+ spikes with bidirectional fMRI signals based on the thalamic regulation of cortical states, depicting a brain-state dependency of both astrocytic Ca2+ and BOLD fMRI signals.
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28
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Genetically encoded indicators of neuronal activity. Nat Neurosci 2017; 19:1142-53. [PMID: 27571193 DOI: 10.1038/nn.4359] [Citation(s) in RCA: 412] [Impact Index Per Article: 58.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Accepted: 07/14/2016] [Indexed: 02/07/2023]
Abstract
Experimental efforts to understand how the brain represents, stores and processes information require high-fidelity recordings of multiple different forms of neural activity within functional circuits. Thus, creating improved technologies for large-scale recordings of neural activity in the live brain is a crucial goal in neuroscience. Over the past two decades, the combination of optical microscopy and genetically encoded fluorescent indicators has become a widespread means of recording neural activity in nonmammalian and mammalian nervous systems, transforming brain research in the process. In this review, we describe and assess different classes of fluorescent protein indicators of neural activity. We first discuss general considerations in optical imaging and then present salient characteristics of representative indicators. Our focus is on how indicator characteristics relate to their use in living animals and on likely areas of future progress.
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29
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Borden PY, Ortiz AD, Waiblinger C, Sederberg AJ, Morrissette AE, Forest CR, Jaeger D, Stanley GB. Genetically expressed voltage sensor ArcLight for imaging large scale cortical activity in the anesthetized and awake mouse. NEUROPHOTONICS 2017; 4:031212. [PMID: 28491905 PMCID: PMC5416966 DOI: 10.1117/1.nph.4.3.031212] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Accepted: 04/10/2017] [Indexed: 06/07/2023]
Abstract
With the recent breakthrough in genetically expressed voltage indicators (GEVIs), there has been a tremendous demand to determine the capabilities of these sensors in vivo. Novel voltage sensitive fluorescent proteins allow for direct measurement of neuron membrane potential changes through changes in fluorescence. Here, we utilized ArcLight, a recently developed GEVI, and examined the functional characteristics in the widely used mouse somatosensory whisker pathway. We measured the resulting evoked fluorescence using a wide-field microscope and a CCD camera at 200 Hz, which enabled voltage recordings over the entire cortical region with high temporal resolution. We found that ArcLight produced a fluorescent response in the S1 barrel cortex during sensory stimulation at single whisker resolution. During wide-field cortical imaging, we encountered substantial hemodynamic noise that required additional post hoc processing through noise subtraction techniques. Over a period of 28 days, we found clear and consistent ArcLight fluorescence responses to a simple sensory input. Finally, we demonstrated the use of ArcLight to resolve cortical S1 sensory responses in the awake mouse. Taken together, our results demonstrate the feasibility of ArcLight as a measurement tool for mesoscopic, chronic imaging.
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Affiliation(s)
- Peter Y. Borden
- Georgia Institute of Technology and Emory University, Wallace H. Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
| | - Alex D. Ortiz
- Georgia Institute of Technology and Emory University, Wallace H. Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
| | - Christian Waiblinger
- Georgia Institute of Technology and Emory University, Wallace H. Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
| | - Audrey J. Sederberg
- Georgia Institute of Technology and Emory University, Wallace H. Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
| | - Arthur E. Morrissette
- Emory University, Neuroscience Program, Department of Biology, Atlanta, Georgia, United States
| | - Craig R. Forest
- Georgia Institute of Technology and Emory University, School of Mechanical Engineering, Atlanta, Georgia, United States
| | - Dieter Jaeger
- Emory University, Neuroscience Program, Department of Biology, Atlanta, Georgia, United States
| | - Garrett B. Stanley
- Georgia Institute of Technology and Emory University, Wallace H. Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
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30
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Abstract
Genetically encoded calcium indicators (GECIs) enable imaging of in vivo brain cell activity with high sensitivity and specificity. In contrast to viral infection or in utero electroporation, indicator expression in transgenic reporter lines is induced noninvasively, reliably, and homogenously. Recently, Cre/tTA-dependent reporter mice were introduced, which provide high-level expression of green fluorescent GECIs in a cell-type-specific and inducible manner when crossed with Cre and tTA driver mice. Here, we generated and characterized the first red-shifted GECI reporter line of this type using R-CaMP1.07, a red fluorescent indicator that is efficiently two-photon excited above 1000 nm. By crossing the new R-CaMP1.07 reporter line to Cre lines driving layer-specific expression in neocortex we demonstrate its high fidelity for reporting action potential firing in vivo, long-term stability over months, and versatile use for functional imaging of excitatory neurons across all cortical layers, especially in the previously difficult to access layers 4 and 6.
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31
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Iijima N, Miyamoto S, Matsumoto K, Takumi K, Ueta Y, Ozawa H. Development of an imaging system for in vivo real-time monitoring of neuronal activity in deep brain of free-moving rats. Histochem Cell Biol 2017; 148:289-298. [PMID: 28550404 DOI: 10.1007/s00418-017-1576-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/28/2017] [Indexed: 12/31/2022]
Abstract
We have newly developed a system that allows monitoring of the intensity of fluorescent signals from deep brains of rats transgenically modified to express enhanced green fluorescent protein (eGFP) via an optical fiber. One terminal of the optical fiber was connected to a blue semiconductor laser oscillator/green fluorescence detector. The other terminal was inserted into the vicinity of the eGFP-expressing neurons. Since the optical fiber was vulnerable to twisting stresses caused by animal movement, we also developed a cage in which the floor automatically turns, in response to the turning of the rat's head. This relieved the twisting stress on the optical fiber. The system then enabled real-time monitoring of fluorescence in awake and unrestrained rats over many hours. Using this system, we could continuously monitor eGFP-expression in arginine vasopressin-eGFP transgenic rats. Moreover, we observed an increase of eGFP-expression in the paraventricular nucleus under salt-loading conditions. We then performed in vivo imaging of eGFP-expressing GnRH neurons in the hypothalamus, via a bundle consisting of 3000 thin optical fibers. With the combination of the optical fiber bundle connection to the fluorescence microscope, and the special cage system, we were able to capture and retain images of eGFP-expressing neurons from free-moving rats. We believe that our newly developed method for monitoring and imaging eGFP-expression in deep brain neurons will be useful for analysis of neuronal functions in awake and unrestrained animals for long durations.
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Affiliation(s)
- Norio Iijima
- Department of Anatomy and Neurobiology, Graduate School of Medicine, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo, 113-8602, Japan. .,Center for Medical Science, International University of Health and Welfare, 2600-1 Kitakanamaru, Ohtawara, 324-8501, Japan.
| | - Shinji Miyamoto
- Indeco Inc., 1-11-14 Kasuga, Bunkyo-ku, Tokyo, 112-0003, Japan.,Activelase, 3-5-22 Imai, Oume-si, Tokyo, Japan
| | - Keisuke Matsumoto
- Department of Anatomy and Neurobiology, Graduate School of Medicine, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo, 113-8602, Japan
| | - Ken Takumi
- Department of Anatomy and Neurobiology, Graduate School of Medicine, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo, 113-8602, Japan.,Department of Zoology, Okayama University of Science, 1-1 Ridai-cho, Okayama, 700-0005, Japan
| | - Yoichi Ueta
- Department of Physiology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, 807-8555, Japan
| | - Hitoshi Ozawa
- Department of Anatomy and Neurobiology, Graduate School of Medicine, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo, 113-8602, Japan
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32
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Zhang Q, Yao J, Guang Y, Liang S, Guan J, Qin H, Liao X, Jin W, Zhang J, Pan J, Jia H, Yan J, Feng Z, Li W, Chen X. Locomotion-Related Population Cortical Ca 2+ Transients in Freely Behaving Mice. Front Neural Circuits 2017; 11:24. [PMID: 28439229 PMCID: PMC5383702 DOI: 10.3389/fncir.2017.00024] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2017] [Accepted: 03/27/2017] [Indexed: 11/25/2022] Open
Abstract
Locomotion involves complex neural activity throughout different cortical and subcortical networks. The primary motor cortex (M1) receives a variety of projections from different brain regions and is responsible for executing movements. The primary visual cortex (V1) receives external visual stimuli and plays an important role in guiding locomotion. Understanding how exactly the M1 and the V1 are involved in locomotion requires recording the neural activities in these areas in freely moving animals. Here, we used an optical fiber-based method for the real-time monitoring of neuronal population activities in freely moving mice. We combined the bulk loading of a synthetic Ca2+ indicator and the optical fiber-based Ca2+ recordings of neuronal activities. An optical fiber 200 μm in diameter can detect the coherent activity of a subpopulation of neurons. In layer 5 of the M1 and V1, we showed that population Ca2+ transients reliably occurred preceding the impending locomotion. Interestingly, the M1 Ca2+ transients started ~100 ms earlier than that in V1. Furthermore, the population Ca2+ transients were robustly correlated with head movements. Thus, our work provides a simple but efficient approach for monitoring the cortical Ca2+ activity of a local cluster of neurons during locomotion in freely moving animals.
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Affiliation(s)
- Quanchao Zhang
- Brain Research Center, Third Military Medical UniversityChongqing, China
| | - Jiwei Yao
- Institute of Urinary Surgery, Southwest Hospital, Third Military Medical UniversityChongqing, China
| | - Yu Guang
- Department of Psychology, Third Military Medical UniversityChongqing, China
| | - Shanshan Liang
- Brain Research Center, Third Military Medical UniversityChongqing, China
| | - Jiangheng Guan
- Brain Research Center, Third Military Medical UniversityChongqing, China
| | - Han Qin
- Brain Research Center, Third Military Medical UniversityChongqing, China
| | - Xiang Liao
- Brain Research Center, Third Military Medical UniversityChongqing, China
| | - Wenjun Jin
- Brain Research Center, Third Military Medical UniversityChongqing, China
| | - Jianxiong Zhang
- Brain Research Center, Third Military Medical UniversityChongqing, China
| | - Junxia Pan
- Brain Research Center, Third Military Medical UniversityChongqing, China
| | - Hongbo Jia
- Brain Research Instrument Innovation Center, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of SciencesSuzhou, China
| | - Junan Yan
- Institute of Urinary Surgery, Southwest Hospital, Third Military Medical UniversityChongqing, China
| | - Zhengzhi Feng
- Department of Psychology, Third Military Medical UniversityChongqing, China
| | - Weibing Li
- Institute of Urinary Surgery, Southwest Hospital, Third Military Medical UniversityChongqing, China.,Clinical Center for Urological Disease, The Third Affiliated Hospital, Chongqing Medical UniversityChongqing, China
| | - Xiaowei Chen
- Brain Research Center, Third Military Medical UniversityChongqing, China.,CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai Institutes for Biological Sciences, Chinese Academy of SciencesShanghai, China
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33
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Zolnik TA, Sha F, Johenning FW, Schreiter ER, Looger LL, Larkum ME, Sachdev RNS. All-optical functional synaptic connectivity mapping in acute brain slices using the calcium integrator CaMPARI. J Physiol 2016; 595:1465-1477. [PMID: 27861906 DOI: 10.1113/jp273116] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 11/04/2016] [Indexed: 01/28/2023] Open
Abstract
KEY POINTS The genetically encoded fluorescent calcium integrator calcium-modulated photoactivatable ratiobetric integrator (CaMPARI) reports calcium influx induced by synaptic and neural activity. Its fluorescence is converted from green to red in the presence of violet light and calcium. The rate of conversion - the sensitivity to activity - is tunable and depends on the intensity of violet light. Synaptic activity and action potentials can independently initiate significant CaMPARI conversion. The level of conversion by subthreshold synaptic inputs is correlated to the strength of input, enabling optical readout of relative synaptic strength. When combined with optogenetic activation of defined presynaptic neurons, CaMPARI provides an all-optical method to map synaptic connectivity. ABSTRACT The calcium-modulated photoactivatable ratiometric integrator (CaMPARI) is a genetically encoded calcium integrator that facilitates the study of neural circuits by permanently marking cells active during user-specified temporal windows. Permanent marking enables measurement of signals from large swathes of tissue and easy correlation of activity with other structural or functional labels. One potential application of CaMPARI is labelling neurons postsynaptic to specific populations targeted for optogenetic stimulation, giving rise to all-optical functional connectivity mapping. Here, we characterized the response of CaMPARI to several common types of neuronal calcium signals in mouse acute cortical brain slices. Our experiments show that CaMPARI is effectively converted by both action potentials and subthreshold synaptic inputs, and that conversion level is correlated to synaptic strength. Importantly, we found that conversion rate can be tuned: it is linearly related to light intensity. At low photoconversion light levels CaMPARI offers a wide dynamic range due to slower conversion rate; at high light levels conversion is more rapid and more sensitive to activity. Finally, we employed CaMPARI and optogenetics for functional circuit mapping in ex vivo acute brain slices, which preserve in vivo-like connectivity of axon terminals. With a single light source, we stimulated channelrhodopsin-2-expressing long-range posteromedial (POm) thalamic axon terminals in cortex and induced CaMPARI conversion in recipient cortical neurons. We found that POm stimulation triggers robust photoconversion of layer 5 cortical neurons and weaker conversion of layer 2/3 neurons. Thus, CaMPARI enables network-wide, tunable, all-optical functional circuit mapping that captures supra- and subthreshold depolarization.
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Affiliation(s)
- Timothy A Zolnik
- Neurocure Center for Excellence, Chariteplatz 1/Virchowweg 6, Charité Universitätsmedizin Berlin and Humboldt Universität, Berlin, 10117, Germany
| | - Fern Sha
- Howard Hughes Medical Institute, Janelia Research Campus, 19700 Helix Drive, Ashburn, VA, 20147, USA
| | - Friedrich W Johenning
- Neuroscience Research Center, Charité Universitätsmedizin Berlin, Charitéplatz 1, Berlin, 10117, Germany
| | - Eric R Schreiter
- Howard Hughes Medical Institute, Janelia Research Campus, 19700 Helix Drive, Ashburn, VA, 20147, USA
| | - Loren L Looger
- Howard Hughes Medical Institute, Janelia Research Campus, 19700 Helix Drive, Ashburn, VA, 20147, USA
| | - Matthew E Larkum
- Neurocure Center for Excellence, Chariteplatz 1/Virchowweg 6, Charité Universitätsmedizin Berlin and Humboldt Universität, Berlin, 10117, Germany
| | - Robert N S Sachdev
- Neurocure Center for Excellence, Chariteplatz 1/Virchowweg 6, Charité Universitätsmedizin Berlin and Humboldt Universität, Berlin, 10117, Germany
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34
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Bishop BH, Spence-Chorman N, Gahtan E. Three-dimensional motion tracking reveals a diving component to visual and auditory escape swims in zebrafish larvae. ACTA ACUST UNITED AC 2016; 219:3981-3987. [PMID: 27802145 DOI: 10.1242/jeb.147124] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Accepted: 10/13/2016] [Indexed: 02/03/2023]
Abstract
Escape behaviors have been studied in zebrafish by neuroscientists seeking cellular-level descriptions of neural circuits but few studies have examined vertical swimming during escapes. We analyzed three-dimensional swimming paths of zebrafish larvae during visually-evoked and auditory-evoked escapes while the fish were in a cubical tank with equal vertical and lateral range. Visually evoked escapes, elicited by sudden dimming of ambient light, consistently elicited downward spiral swimming (dives) with faster vertical than lateral movement. Auditory taps also elicited rapid escape swimming with equivalent total distance traveled but with significantly less vertical and more lateral movement. Visually evoked dives usually ended with the zebrafish hitting the bottom of the 10 cm3 tank. Therefore, visually evoked dives were also analyzed in a tubular tank with 50 cm of vertical range, and in most cases larvae reached the bottom of that tank during a 120 s dimming stimulus. Light-evoked spiral diving in zebrafish may be an innate defense reflex against specific predation threats. Since visual and auditory escapes are initially similar but dives persist only during visual escapes, our findings lay the groundwork for studying a type of decision-making within zebrafish sensorimotor circuits.
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Affiliation(s)
- Benjamin H Bishop
- Department of Psychology, Humboldt State University, 1 Harpst Street, Arcata, CA 95521, USA
| | - Nathan Spence-Chorman
- Department of Psychology, Humboldt State University, 1 Harpst Street, Arcata, CA 95521, USA
| | - Ethan Gahtan
- Department of Psychology, Humboldt State University, 1 Harpst Street, Arcata, CA 95521, USA
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35
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ON and OFF retinal ganglion cells differentially regulate serotonergic and GABAergic activity in the dorsal raphe nucleus. Sci Rep 2016; 6:26060. [PMID: 27181078 PMCID: PMC4867631 DOI: 10.1038/srep26060] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 04/27/2016] [Indexed: 11/08/2022] Open
Abstract
The dorsal raphe nucleus (DRN), the major source of serotonergic input to the forebrain, receives excitatory input from the retina that can modulate serotonin levels and depressive-like behavior. In the Mongolian gerbil, retinal ganglion cells (RGCs) with alpha-like morphological and Y-like physiological properties innervate the DRN with ON DRN-projecting RGCs out numbering OFF DRN-projecting RGCs. The DRN neurons targeted by ON and OFF RGCs are unknown. To explore retino-raphe anatomical organization, retinal afferents labeled with Cholera toxin B were examined for association with the postsynaptic protein PSD-95. Synaptic associations between retinal afferents and DRN serotonergic and GABAergic neurons were observed. To explore retino-raphe functional organization, light-evoked c-fos expression was examined. Light significantly increased the number of DRN serotonergic and GABAergic cells expressing c-Fos. When ON RGCs were rendered silent while enhancing the firing rate of OFF RGCs, c-Fos expression was greatly increased in DRN serotonergic neurons suggesting that OFF DRN-projecting RGCs predominately activate serotonergic neurons whereas ON DRN-projecting RGCs mainly target GABAergic neurons. Direct glutamatergic retinal input to DRN 5-HT neurons contributes to the complex excitatory drive regulating these cells. Light, via the retinoraphe pathway can modify DRN 5-HT neuron activity which may play a role in modulating affective behavior.
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36
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Lissek T, Obenhaus HA, Ditzel DAW, Nagai T, Miyawaki A, Sprengel R, Hasan MT. General Anesthetic Conditions Induce Network Synchrony and Disrupt Sensory Processing in the Cortex. Front Cell Neurosci 2016; 10:64. [PMID: 27147963 PMCID: PMC4830828 DOI: 10.3389/fncel.2016.00064] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Accepted: 02/29/2016] [Indexed: 12/19/2022] Open
Abstract
General anesthetics are commonly used in animal models to study how sensory signals are represented in the brain. Here, we used two-photon (2P) calcium activity imaging with cellular resolution to investigate how neuronal activity in layer 2/3 of the mouse barrel cortex is modified under the influence of different concentrations of chemically distinct general anesthetics. Our results show that a high isoflurane dose induces synchrony in local neuronal networks and these cortical activity patterns closely resemble those observed in EEG recordings under deep anesthesia. Moreover, ketamine and urethane also induced similar activity patterns. While investigating the effects of deep isoflurane anesthesia on whisker and auditory evoked responses in the barrel cortex, we found that dedicated spatial regions for sensory signal processing become disrupted. We propose that our isoflurane-2P imaging paradigm can serve as an attractive model system to dissect cellular and molecular mechanisms that induce the anesthetic state, and it might also provide important insight into sleep-like brain states and consciousness.
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Affiliation(s)
- Thomas Lissek
- Department of Molecular Neurobiology, Max Planck Institute for Medical ResearchHeidelberg, Germany; Department of Neurobiology, Interdisciplinary Center for Neurosciences, University of HeidelbergHeidelberg, Germany
| | - Horst A Obenhaus
- Department of Molecular Neurobiology, Max Planck Institute for Medical Research Heidelberg, Germany
| | - Désirée A W Ditzel
- Department of Molecular Neurobiology, Max Planck Institute for Medical ResearchHeidelberg, Germany; Max Planck Research Group at the Institute for Anatomy and Cell Biology, Heidelberg UniversityHeidelberg, Germany
| | - Takeharu Nagai
- Laboratory for Nanosystems Physiology, Hokkaido University Hokkaido, Japan
| | - Atsushi Miyawaki
- RIKEN-Brain Science Institute, Laboratory for Cell Function Dynamics Saitama, Japan
| | - Rolf Sprengel
- Department of Molecular Neurobiology, Max Planck Institute for Medical ResearchHeidelberg, Germany; Max Planck Research Group at the Institute for Anatomy and Cell Biology, Heidelberg UniversityHeidelberg, Germany
| | - Mazahir T Hasan
- Department of Molecular Neurobiology, Max Planck Institute for Medical ResearchHeidelberg, Germany; Molecular Neurobiology, Neurocure Cluster of Excellence, Charite-UniversitätsmedizinBerlin, Germany
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37
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Dogbevia GK, Roβmanith M, Sprengel R, Hasan MT. Flexible, AAV-equipped Genetic Modules for Inducible Control of Gene Expression in Mammalian Brain. MOLECULAR THERAPY. NUCLEIC ACIDS 2016; 5:e309. [PMID: 27070301 PMCID: PMC5014524 DOI: 10.1038/mtna.2016.23] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2015] [Accepted: 03/01/2016] [Indexed: 12/17/2022]
Abstract
Controlling gene expression in mammalian brain is of utmost importance to causally link the role of gene function to cell circuit dynamics under normal conditions and disease states. We have developed recombinant adeno-associated viruses equipped with tetracycline-controlled genetic switches for inducible and reversible control of gene expression in a cell type specific and brain subregion selective manner. Here, we characterize a two-virus approach to efficiently and reliably switch gene expression on and off, repetitively, both in vitro and in vivo. Our recombinant adeno-associated virus (rAAV)-Tet approach is highly flexible and it has great potential for application in basic and biomedical neuroscience research and gene therapy.
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Affiliation(s)
- Godwin K Dogbevia
- Department of Neurobiology, Max Planck Institute for Medical Research, Heidelberg, Germany.,Institute of Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Lübeck, Germany
| | - Martin Roβmanith
- Department of Neurobiology, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Rolf Sprengel
- Max Planck Research Group at the Institute for Anatomy and Cell Biology, Heidelberg University, Heidelberg, Germany
| | - Mazahir T Hasan
- Department of Neurobiology, Max Planck Institute for Medical Research, Heidelberg, Germany.,Charité-Universitätsmedizin, NeuroCure Cluster of Excellence, Berlin, Germany
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38
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Kim CK, Yang SJ, Pichamoorthy N, Young NP, Kauvar I, Jennings JH, Lerner TN, Berndt A, Lee SY, Ramakrishnan C, Davidson TJ, Inoue M, Bito H, Deisseroth K. Simultaneous fast measurement of circuit dynamics at multiple sites across the mammalian brain. Nat Methods 2016; 13:325-8. [PMID: 26878381 PMCID: PMC5717315 DOI: 10.1038/nmeth.3770] [Citation(s) in RCA: 276] [Impact Index Per Article: 34.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Accepted: 01/14/2016] [Indexed: 02/08/2023]
Abstract
Real-time activity measurements from multiple specific cell populations and projections are likely to be important for understanding the brain as a dynamical system. Here we developed frame-projected independent-fiber photometry (FIP), which we used to record fluorescence activity signals from many brain regions simultaneously in freely behaving mice. We explored the versatility of the FIP microscope by quantifying real-time activity relationships among many brain regions during social behavior, simultaneously recording activity along multiple axonal pathways during sensory experience, performing simultaneous two-color activity recording, and applying optical perturbation tuned to elicit dynamics that match naturally occurring patterns observed during behavior.
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Affiliation(s)
- Christina K Kim
- Neurosciences Program, Stanford University, Stanford, California, USA
| | - Samuel J Yang
- Department of Electrical Engineering, Stanford University, Stanford, California, USA
| | | | - Noah P Young
- Department of Bioengineering, Stanford University, Stanford, California, USA
| | - Isaac Kauvar
- Department of Electrical Engineering, Stanford University, Stanford, California, USA
| | - Joshua H Jennings
- Department of Bioengineering, Stanford University, Stanford, California, USA
| | - Talia N Lerner
- Department of Bioengineering, Stanford University, Stanford, California, USA
| | - Andre Berndt
- Department of Bioengineering, Stanford University, Stanford, California, USA
| | - Soo Yeun Lee
- Department of Bioengineering, Stanford University, Stanford, California, USA
| | - Charu Ramakrishnan
- Department of Bioengineering, Stanford University, Stanford, California, USA
| | - Thomas J Davidson
- Department of Bioengineering, Stanford University, Stanford, California, USA
| | - Masatoshi Inoue
- Department of Neurochemistry, Graduate School of Medicine, University of Tokyo, Tokyo, Japan
- Core Research for Evolutional Science and Technology, Japan Agency for Medical Research and Development, Tokyo, Japan
| | - Haruhiko Bito
- Department of Neurochemistry, Graduate School of Medicine, University of Tokyo, Tokyo, Japan
- Core Research for Evolutional Science and Technology, Japan Agency for Medical Research and Development, Tokyo, Japan
| | - Karl Deisseroth
- Department of Bioengineering, Stanford University, Stanford, California, USA
- Howard Hughes Medical Institute, Stanford University, Stanford, California, USA
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, California, USA
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39
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Lerner TN, Ye L, Deisseroth K. Communication in Neural Circuits: Tools, Opportunities, and Challenges. Cell 2016; 164:1136-1150. [PMID: 26967281 PMCID: PMC5725393 DOI: 10.1016/j.cell.2016.02.027] [Citation(s) in RCA: 109] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Revised: 01/27/2016] [Accepted: 02/03/2016] [Indexed: 11/27/2022]
Abstract
Communication, the effective delivery of information, is fundamental to life across all scales and species. Nervous systems (by necessity) may be most specifically adapted among biological tissues for high rate and complexity of information transmitted, and thus, the properties of neural tissue and principles of its organization into circuits may illuminate capabilities and limitations of biological communication. Here, we consider recent developments in tools for studying neural circuits with particular attention to defining neuronal cell types by input and output information streams--i.e., by how they communicate. Complementing approaches that define cell types by virtue of genetic promoter/enhancer properties, this communication-based approach to defining cell types operationally by input/output (I/O) relationships links structure and function, resolves difficulties associated with single-genetic-feature definitions, leverages technology for observing and testing significance of precisely these I/O relationships in intact brains, and maps onto processes through which behavior may be adapted during development, experience, and evolution.
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Affiliation(s)
- Talia N Lerner
- Bioengineering Department, 318 Campus Drive, Stanford University, Stanford, CA 94305, USA
| | - Li Ye
- Bioengineering Department, 318 Campus Drive, Stanford University, Stanford, CA 94305, USA
| | - Karl Deisseroth
- Bioengineering Department, 318 Campus Drive, Stanford University, Stanford, CA 94305, USA; Psychiatry Department, 318 Campus Drive, Stanford University, Stanford, CA 94305, USA; Howard Hughes Medical Institute, 318 Campus Drive, Stanford University, Stanford, CA 94305, USA.
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40
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Lee SA, Holly KS, Voziyanov V, Villalba SL, Tong R, Grigsby HE, Glasscock E, Szele FG, Vlachos I, Murray TA. Gradient Index Microlens Implanted in Prefrontal Cortex of Mouse Does Not Affect Behavioral Test Performance over Time. PLoS One 2016; 11:e0146533. [PMID: 26799938 PMCID: PMC4723314 DOI: 10.1371/journal.pone.0146533] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Accepted: 12/19/2015] [Indexed: 12/11/2022] Open
Abstract
Implanted gradient index lenses have extended the reach of standard multiphoton microscopy from the upper layers of the mouse cortex to the lower cortical layers and even subcortical regions. These lenses have the clarity to visualize dynamic activities, such as calcium transients, with subcellular and millisecond resolution and the stability to facilitate repeated imaging over weeks and months. In addition, behavioral tests can be used to correlate performance with observed changes in network function and structure that occur over time. Yet, this raises the questions, does an implanted microlens have an effect on behavioral tests, and if so, what is the extent of the effect? To answer these questions, we compared the performance of three groups of mice in three common behavioral tests. A gradient index lens was implanted in the prefrontal cortex of experimental mice. We compared their performance with mice that had either a cranial window or a sham surgery. Three presurgical and five postsurgical sets of behavioral tests were performed over seven weeks. Behavioral tests included rotarod, foot fault, and Morris water maze. No significant differences were found between the three groups, suggesting that microlens implantation did not affect performance. The results for the current study clear the way for combining behavioral studies with gradient index lens imaging in the prefrontal cortex, and potentially other regions of the mouse brain, to study structural, functional, and behavioral relationships in the brain.
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Affiliation(s)
- Seon A. Lee
- Center for Biomedical Research and Rehabilitation Sciences, Louisiana Tech University, Ruston, Louisiana, United States of America
| | - Kevin S. Holly
- Center for Biomedical Research and Rehabilitation Sciences, Louisiana Tech University, Ruston, Louisiana, United States of America
| | - Vladislav Voziyanov
- Center for Biomedical Research and Rehabilitation Sciences, Louisiana Tech University, Ruston, Louisiana, United States of America
| | - Stephanie L. Villalba
- Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center, Shreveport, LA, United States of America
| | - Rudi Tong
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Holly E. Grigsby
- Center for Biomedical Research and Rehabilitation Sciences, Louisiana Tech University, Ruston, Louisiana, United States of America
| | - Edward Glasscock
- Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center, Shreveport, LA, United States of America
| | - Francis G. Szele
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Ioannis Vlachos
- Center for Biomedical Research and Rehabilitation Sciences, Louisiana Tech University, Ruston, Louisiana, United States of America
| | - Teresa A. Murray
- Center for Biomedical Research and Rehabilitation Sciences, Louisiana Tech University, Ruston, Louisiana, United States of America
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41
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Roh M, Lee K, Jang IS, Suk K, Lee MG. Acrylic Resin Molding Based Head Fixation Technique in Rodents. J Vis Exp 2016:e53064. [PMID: 26862716 DOI: 10.3791/53064] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Head fixation is a technique of immobilizing animal's head by attaching a head-post on the skull for rigid clamping. Traditional head fixation requires surgical attachment of metallic frames on the skull. The attached frames are then clamped to a stationary platform resulting in immobilization of the head. However, metallic frames for head fixation have been technically difficult to design and implement in general laboratory environment. In this study, we provide a novel head fixation method. Using a custom-made head fixation bar, head mounter is constructed during implantation surgery. After the application of acrylic resin for affixing implants such as electrodes and cannula on the skull, additional resins applied on top of that to build a mold matching to the port of the fixation bar. The molded head mounter serves as a guide rails, investigators conveniently fixate the animal's head by inserting the head mounter into the port of the fixation bar. This method could be easily applicable if implantation surgery using dental acrylics is necessary and might be useful for laboratories that cannot easily fabricate CNC machined metal head-posts.
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Affiliation(s)
- Mootaek Roh
- Department of Anatomy, School of Medicine and Brain Science and Engineering Institute, Kyungpook National University
| | - Kyungmin Lee
- Department of Anatomy, School of Medicine and Brain Science and Engineering Institute, Kyungpook National University
| | - Il-Sung Jang
- Department of Pharmacology, School of Dentistry and Brain Science and Engineering Institute, Kyungpook National University
| | - Kyoungho Suk
- Department of Pharmacology, School of Medicine and Brain Science and Engineering Institute, Kyungpook National University
| | - Maan-Gee Lee
- Department of Pharmacology, School of Medicine and Brain Science and Engineering Institute, Kyungpook National University;
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42
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Yoshikawa S, Usami T, Kikuta J, Ishii M, Sasano T, Sugiyama K, Furukawa T, Nakasho E, Takayanagi H, Tedder TF, Karasuyama H, Miyawaki A, Adachi T. Intravital imaging of Ca(2+) signals in lymphocytes of Ca(2+) biosensor transgenic mice: indication of autoimmune diseases before the pathological onset. Sci Rep 2016; 6:18738. [PMID: 26732477 PMCID: PMC4702216 DOI: 10.1038/srep18738] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 11/25/2015] [Indexed: 12/27/2022] Open
Abstract
Calcium ion (Ca(2+)) signaling is a typical phenomenon mediated through immune receptors, such as the B-cell antigen receptor (BCR), and it is important for their biological activities. To analyze the signaling of immune receptors together with their in vivo dynamics, we generated stable transgenic mice with the Föster/fluorescence resonance energy transfer (FRET)-based Ca(2+) indicator yellow cameleon 3.60 (YC3.60), based on the Cre/loxP system (YC3.60(flox)). We successfully obtained mice with specific YC3.60 expression in immune or nerve cells as well as mice with ubiquitous expression of this indicator. We established five-dimensional (5D) (x, y, z, time, and Ca(2+)) intravital imaging of lymphoid tissues, including the bone marrow. Furthermore, in autoimmune-prone models, the CD22(-/-) and C57BL/6- lymphoproliferation (lpr)/lpr mouse, Ca(2+) fluxes were augmented, although they did not induce autoimmune disease. Intravital imaging of Ca(2+) signals in lymphocytes may improve assessment of the risk of autoimmune diseases in model animals.
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Affiliation(s)
- Soichiro Yoshikawa
- Department of Immune Regulation, Tokyo Medical and Dental University, Tokyo, 113-8519, Japan
| | - Takako Usami
- Laboratory of recombinant animals, Medical Research Institute, Tokyo Medical and Dental University, Tokyo, 101-0062, Japan
| | - Junichi Kikuta
- Immunology and Cell Biology, Graduate School of Medicine, Osaka University, Suita 565-0871, Japan
| | - Masaru Ishii
- Immunology and Cell Biology, Graduate School of Medicine, Osaka University, Suita 565-0871, Japan
| | - Tetsuo Sasano
- Department of Biofunctional Informatics, Tokyo Medical and Dental University, Tokyo 113-8519, Japan
| | - Koji Sugiyama
- Department of Bio-informational Pharmacology, Medical Research Institute, Tokyo Medical and Dental University, Tokyo 113-8510, Japan
| | - Tetsushi Furukawa
- Department of Bio-informational Pharmacology, Medical Research Institute, Tokyo Medical and Dental University, Tokyo 113-8510, Japan
| | - Eiji Nakasho
- R&D Group, Scientific Solutions Product Development Division, Olympus Corporation, Hachioji-shi, Tokyo 192-8507, Japan
| | - Hiroshi Takayanagi
- Department of Immunology, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
| | - Thomas F Tedder
- Department of Immunology, Duke University Medical Center, Durham, NC 27710
| | - Hajime Karasuyama
- Department of Immune Regulation, Tokyo Medical and Dental University, Tokyo, 113-8519, Japan
| | - Atsushi Miyawaki
- Laboratory for Cell Function and Dynamics, Advanced Technology Development Group, Brain Science Institute, RIKEN, Wako, Saitama 351-0198, Japan
| | - Takahiro Adachi
- Department of Immunology, Medical Research Institute, Tokyo Medical and Dental University, Tokyo, 113-8510, Japan
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43
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Guo Q, Zhou J, Feng Q, Lin R, Gong H, Luo Q, Zeng S, Luo M, Fu L. Multi-channel fiber photometry for population neuronal activity recording. BIOMEDICAL OPTICS EXPRESS 2015; 6:3919-31. [PMID: 26504642 PMCID: PMC4605051 DOI: 10.1364/boe.6.003919] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 08/31/2015] [Accepted: 09/07/2015] [Indexed: 05/05/2023]
Abstract
Fiber photometry has become increasingly popular among neuroscientists as a convenient tool for the recording of genetically defined neuronal population in behaving animals. Here, we report the development of the multi-channel fiber photometry system to simultaneously monitor neural activities in several brain areas of an animal or in different animals. In this system, a galvano-mirror modulates and cyclically couples the excitation light to individual multimode optical fiber bundles. A single photodetector collects excited light and the configuration of fiber bundle assembly and the scanner determines the total channel number. We demonstrated that the system exhibited negligible crosstalk between channels and optical signals could be sampled simultaneously with a sample rate of at least 100 Hz for each channel, which is sufficient for recording calcium signals. Using this system, we successfully recorded GCaMP6 fluorescent signals from the bilateral barrel cortices of a head-restrained mouse in a dual-channel mode, and the orbitofrontal cortices of multiple freely moving mice in a triple-channel mode. The multi-channel fiber photometry system would be a valuable tool for simultaneous recordings of population activities in different brain areas of a given animal and different interacting individuals.
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Affiliation(s)
- Qingchun Guo
- Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics-Huazhong University of Science and Technology, Wuhan 430074, China
- MoE Key Laboratory for Biomedical Photonics, Department of Biomedical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
- These authors contributed equally to this work
| | - Jingfeng Zhou
- PTN Graduate Program, School of Life Sciences, Peking University, Beijing 100081, China
- National Institute of Biological Sciences, Beijing 102206, China
- These authors contributed equally to this work
| | - Qiru Feng
- National Institute of Biological Sciences, Beijing 102206, China
| | - Rui Lin
- National Institute of Biological Sciences, Beijing 102206, China
| | - Hui Gong
- Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics-Huazhong University of Science and Technology, Wuhan 430074, China
- MoE Key Laboratory for Biomedical Photonics, Department of Biomedical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Qingming Luo
- Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics-Huazhong University of Science and Technology, Wuhan 430074, China
- MoE Key Laboratory for Biomedical Photonics, Department of Biomedical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Shaoqun Zeng
- Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics-Huazhong University of Science and Technology, Wuhan 430074, China
- MoE Key Laboratory for Biomedical Photonics, Department of Biomedical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Minmin Luo
- National Institute of Biological Sciences, Beijing 102206, China
- School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Ling Fu
- Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics-Huazhong University of Science and Technology, Wuhan 430074, China
- MoE Key Laboratory for Biomedical Photonics, Department of Biomedical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
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44
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Gautam V, Drury J, Choy JMC, Stricker C, Bachor HA, Daria VR. Improved two-photon imaging of living neurons in brain tissue through temporal gating. BIOMEDICAL OPTICS EXPRESS 2015; 6:4027-36. [PMID: 26504651 PMCID: PMC4605060 DOI: 10.1364/boe.6.004027] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Revised: 09/11/2015] [Accepted: 09/11/2015] [Indexed: 05/05/2023]
Abstract
We optimize two-photon imaging of living neurons in brain tissue by temporally gating an incident laser to reduce the photon flux while optimizing the maximum fluorescence signal from the acquired images. Temporal gating produces a bunch of ~10 femtosecond pulses and the fluorescence signal is improved by increasing the bunch-pulse energy. Gating is achieved using an acousto-optic modulator with a variable gating frequency determined as integral multiples of the imaging sampling frequency. We hypothesize that reducing the photon flux minimizes the photo-damage to the cells. Our results, however, show that despite producing a high fluorescence signal, cell viability is compromised when the gating and sampling frequencies are equal (or effectively one bunch-pulse per pixel). We found an optimum gating frequency range that maintains the viability of the cells while preserving a pre-set fluorescence signal of the acquired two-photon images. The neurons are imaged while under whole-cell patch, and the cell viability is monitored as a change in the membrane's input resistance.
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Affiliation(s)
- Vini Gautam
- John Curtin School of Medical Research, The Australian National University, Canberra, ACT 2601, Australia
| | - Jack Drury
- John Curtin School of Medical Research, The Australian National University, Canberra, ACT 2601, Australia
| | - Julian M. C. Choy
- John Curtin School of Medical Research, The Australian National University, Canberra, ACT 2601, Australia
| | - Christian Stricker
- John Curtin School of Medical Research, The Australian National University, Canberra, ACT 2601, Australia
- Medical School, The Australian National University, Canberra, ACT 2601, Australia
| | - Hans-A. Bachor
- Research School of Physics and Engineering, The Australian National University, Canberra, ACT 2601, Australia
| | - Vincent R. Daria
- John Curtin School of Medical Research, The Australian National University, Canberra, ACT 2601, Australia
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45
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Bellay T, Klaus A, Seshadri S, Plenz D. Irregular spiking of pyramidal neurons organizes as scale-invariant neuronal avalanches in the awake state. eLife 2015; 4:e07224. [PMID: 26151674 PMCID: PMC4492006 DOI: 10.7554/elife.07224] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Accepted: 06/10/2015] [Indexed: 12/22/2022] Open
Abstract
Spontaneous fluctuations in neuronal activity emerge at many spatial and temporal scales in cortex. Population measures found these fluctuations to organize as scale-invariant neuronal avalanches, suggesting cortical dynamics to be critical. Macroscopic dynamics, though, depend on physiological states and are ambiguous as to their cellular composition, spatiotemporal origin, and contributions from synaptic input or action potential (AP) output. Here, we study spontaneous firing in pyramidal neurons (PNs) from rat superficial cortical layers in vivo and in vitro using 2-photon imaging. As the animal transitions from the anesthetized to awake state, spontaneous single neuron firing increases in irregularity and assembles into scale-invariant avalanches at the group level. In vitro spike avalanches emerged naturally yet required balanced excitation and inhibition. This demonstrates that neuronal avalanches are linked to the global physiological state of wakefulness and that cortical resting activity organizes as avalanches from firing of local PN groups to global population activity. DOI:http://dx.doi.org/10.7554/eLife.07224.001 Even when we are not engaged in any specific task, the brain shows coordinated patterns of spontaneous activity that can be monitored using electrodes placed on the scalp. This resting activity shapes the way that the brain responds to subsequent stimuli. Changes in resting activity patterns are seen in various neurological and psychiatric disorders, as well as in healthy individuals following sleep deprivation. The brain's outer layer is known as the cortex. On a large scale, when monitoring many thousands of neurons, resting activity in the cortex demonstrates propagation in the brain in an organized manner. Specifically, resting activity was found to organize as so-called neuronal avalanches, in which large bursts of neuronal activity are grouped with medium-sized and smaller bursts in a very characteristic order. In fact, the sizes of these bursts—that is, the number of neurons that fire—are found to be scale-invariant, that is, the ratio of large bursts to medium-sized bursts is the same as that of medium-sized to small bursts. Such scale-invariance suggests that neuronal bursts are not independent of one another. However, it is largely unclear how neuronal avalanches arise from individual neurons, which fire simply in a noisy, irregular manner. Bellay, Klaus et al. have now provided insights into this process by examining patterns of firing of a particular type of neuron—known as a pyramidal cell—in the cortex of rats as they recover from anesthesia. As the animals awaken, the firing of individual pyramidal cells in the cortex becomes even more irregular than under anesthesia. However, by considering the activity of a group of these neurons, Bellay, Klaus et al. realized that it is this more irregular firing that gives rise to neuronal avalanches, and that this occurs only when the animals are awake. Further experiments on individual pyramidal cells grown in the laboratory confirmed that neuronal avalanches emerge spontaneously from the irregular firing of individual neurons. These avalanches depend on there being a balance between two types of activity among the cells: ‘excitatory’ activity that causes other neurons to fire, and ‘inhibitory’ activity that prevents neuronal firing. Given that resting activity influences the brain's responses to the outside world, the origins of neuronal avalanches are likely to provide clues about the way the brain processes information. Future experiments should also examine the possibility that the emergence of neuronal avalanches marks the transition from unconsciousness to wakefulness within the brain. DOI:http://dx.doi.org/10.7554/eLife.07224.002
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Affiliation(s)
- Timothy Bellay
- Section on Critical Brain Dynamics, National Institute of Mental Health, Bethesda, United States
| | - Andreas Klaus
- Section on Critical Brain Dynamics, National Institute of Mental Health, Bethesda, United States
| | - Saurav Seshadri
- Section on Critical Brain Dynamics, National Institute of Mental Health, Bethesda, United States
| | - Dietmar Plenz
- Section on Critical Brain Dynamics, National Institute of Mental Health, Bethesda, United States
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46
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Heindorf M, Hasan MT. Fluorescent Calcium Indicator Protein Expression in the Mouse Brain Using Recombinant Adeno-Associated Viruses. Cold Spring Harb Protoc 2015; 2015:697-709. [PMID: 26134910 DOI: 10.1101/pdb.prot087635] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
One method for gene delivery and long-term fluorescent calcium indicator protein (FCIP) expression in mammalian neurons in vivo involves the introduction of FCIPs via recombinant adeno-associated virus (rAAV) vectors using constitutive and cell type-specific promoters. This protocol describes the use of rAAVs to express FCIPs in the brain for imaging. Human embryonic kidney 293 cells are first transfected using calcium phosphate. rAAV is then prepared using either an iodixanol gradient or a heparin column. After the virus is purified, its quality is assessed by sodium dodecyl sulfate polyacrylamide gel electrophoresis, estimation of genomic and functional virus titers by quantitative polymerase chain reaction, and expression in dissociated neurons. Mice are injected with rAAV using a stereotactic instrument and can be imaged ∼3 wk later.
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47
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Abstract
Genetically encoded optical actuators and indicators have changed the landscape of neuroscience, enabling targetable control and readout of specific components of intact neural circuits in behaving animals. Here, we review the development of optical neural interfaces, focusing on hardware designed for optical control of neural activity, integrated optical control and electrical readout, and optical readout of population and single-cell neural activity in freely moving mammals.
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Affiliation(s)
- Melissa R Warden
- Department of Neurobiology and Behavior, Cornell University, Ithaca, New York 14853;
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48
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Horikawa K. Recent progress in the development of genetically encoded Ca 2+ indicators. THE JOURNAL OF MEDICAL INVESTIGATION 2015; 62:24-8. [DOI: 10.2152/jmi.62.24] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Kazuki Horikawa
- Division for Bio-imaging, Support Center for Advanced Medical Sciences, Institute of Health Biosciences, the University of Tokushima Graduate School
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49
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Broussard GJ, Liang R, Tian L. Monitoring activity in neural circuits with genetically encoded indicators. Front Mol Neurosci 2014; 7:97. [PMID: 25538558 PMCID: PMC4256991 DOI: 10.3389/fnmol.2014.00097] [Citation(s) in RCA: 101] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Accepted: 11/15/2014] [Indexed: 12/18/2022] Open
Abstract
Recent developments in genetically encoded indicators of neural activity (GINAs) have greatly advanced the field of systems neuroscience. As they are encoded by DNA, GINAs can be targeted to genetically defined cellular populations. Combined with fluorescence microscopy, most notably multi-photon imaging, GINAs allow chronic simultaneous optical recordings from large populations of neurons or glial cells in awake, behaving mammals, particularly rodents. This large-scale recording of neural activity at multiple temporal and spatial scales has greatly advanced our understanding of the dynamics of neural circuitry underlying behavior—a critical first step toward understanding the complexities of brain function, such as sensorimotor integration and learning. Here, we summarize the recent development and applications of the major classes of GINAs. In particular, we take an in-depth look at the design of available GINA families with a particular focus on genetically encoded calcium indicators (GCaMPs), sensors probing synaptic activity, and genetically encoded voltage indicators. Using the family of the GCaMP as an example, we review established sensor optimization pipelines. We also discuss practical considerations for end users of GINAs about experimental methods including approaches for gene delivery, imaging system requirements, and data analysis techniques. With the growing toolbox of GINAs and with new microscopy techniques pushing beyond their current limits, the age of light can finally achieve the goal of broad and dense sampling of neuronal activity across time and brain structures to obtain a dynamic picture of brain function.
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Affiliation(s)
- Gerard J Broussard
- Department of Biochemistry and Molecular Medicine, University of California Davis Davis, CA, USA ; Neuroscience Graduate Group, University of California Davis Davis, CA, USA
| | - Ruqiang Liang
- Department of Biochemistry and Molecular Medicine, University of California Davis Davis, CA, USA
| | - Lin Tian
- Department of Biochemistry and Molecular Medicine, University of California Davis Davis, CA, USA ; Neuroscience Graduate Group, University of California Davis Davis, CA, USA
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50
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Rose T, Goltstein PM, Portugues R, Griesbeck O. Putting a finishing touch on GECIs. Front Mol Neurosci 2014; 7:88. [PMID: 25477779 PMCID: PMC4235368 DOI: 10.3389/fnmol.2014.00088] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Accepted: 10/29/2014] [Indexed: 01/12/2023] Open
Abstract
More than a decade ago genetically encoded calcium indicators (GECIs) entered the stage as new promising tools to image calcium dynamics and neuronal activity in living tissues and designated cell types in vivo. From a variety of initial designs two have emerged as promising prototypes for further optimization: FRET (Förster Resonance Energy Transfer)-based sensors and single fluorophore sensors of the GCaMP family. Recent efforts in structural analysis, engineering and screening have broken important performance thresholds in the latest generation for both classes. While these improvements have made GECIs a powerful means to perform physiology in living animals, a number of other aspects of sensor function deserve attention. These aspects include indicator linearity, toxicity and slow response kinetics. Furthermore creating high performance sensors with optically more favorable emission in red or infrared wavelengths as well as new stably or conditionally GECI-expressing animal lines are on the wish list. When the remaining issues are solved, imaging of GECIs will finally have crossed the last milestone, evolving from an initial promise into a fully matured technology.
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Affiliation(s)
- Tobias Rose
- Max-Planck-Institute of Neurobiology Martinsried, Germany
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