1
|
Han X, Cramer SR, Chan DCY, Zhang N. Exploring memory-related network via dorsal hippocampus suppression. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.03.597201. [PMID: 38895299 PMCID: PMC11185736 DOI: 10.1101/2024.06.03.597201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
Memory is a complex brain process that requires coordinated activities in a large-scale brain network. However, the relationship between coordinated brain network activities and memory-related behavior is not well understood. In this study, we investigated this issue by suppressing the activity in the dorsal hippocampus (dHP) using chemogenetics and measuring the corresponding changes in brain-wide resting-state functional connectivity (RSFC) and memory behavior in awake rats. We identified an extended brain network contributing to the performance in a spatial-memory related task. Our results were cross-validated using two different chemogenetic actuators, clozapine (CLZ) and clozapine-N-oxide (CNO). This study provides a brain network interpretation of memory performance, indicating that memory is associated with coordinated brain-wide neural activities. Significance Statement Successful memory processes require coordinated activity in a large-scale brain network, extending beyond a few key, well-known brain regions like the hippocampus. However, the specific brain regions involved and how they orchestrate their activity that is pertinent to memory processing remain unclear. Our study, using a chemogenetics-rsfMRI- behavior approach in awake rats, elucidates a comprehensive framework of the extended memory-associated network. This knowledge offers a broader interpretation of memory processes, enhancing our understanding of the neural mechanisms behind memory function, particularly from a network perspective.
Collapse
|
2
|
Chang Y, Lusk S, Chang A, Ward CS, Ray RS. Vglut2-based glutamatergic signaling in central noradrenergic neurons is dispensable for normal breathing and chemosensory reflexes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.04.16.535729. [PMID: 37090585 PMCID: PMC10120737 DOI: 10.1101/2023.04.16.535729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
Abstract
Central noradrenergic (NA) neurons are key constituents of the respiratory homeostatic network. NA dysfunction is implicated in several developmental respiratory disorders including Congenital Central Hyperventilation Syndrome (CCHS), Sudden Infant Death Syndrome (SIDS) and Rett Syndrome. The current unchallenged paradigm in the field, supported by multiple studies, is that glutamate co-transmission in subsets of central NA neurons plays a role in breathing control. If true, NA-glutamate co-transmission may also be mechanistically important in respiratory disorders. However, the requirement of NA-derived glutamate in breathing has not been directly tested and the extent of glutamate co-transmission in the central NA system remains uncharacterized. Therefore, we fully characterized the cumulative fate maps and acute adult expression patterns of all three Vesicular Glutamate Transporters ( Slc17a7 (Vglut1), Slc17a6 (Vglut2), and Slc17a8 (Vglut3)) in NA neurons, identifying a novel, dynamic expression pattern for Vglut2 and an undescribed co-expression domain for Vglut3 in the NA system. In contrast to our initial hypothesis that NA derived glutamate is required to breathing, our functional studies showed that loss of Vglut2 throughout the NA system failed to alter breathing or metabolism under room air, hypercapnia, or hypoxia in unrestrained and unanesthetized mice. These data demonstrate that Vglut2-based glutamatergic signaling within the central NA system is not required for normal baseline breathing and hypercapnic, hypoxic chemosensory reflexes. These outcomes challenge the current understanding of central NA neurons in the control of breathing and suggests that glutamate may not be a critical target to understand NA neuron dysfunction in respiratory diseases.
Collapse
|
3
|
Klein E, Marsh S, Becker J, Andermann M, Lehtinen M, Moore CI. BioLuminescent OptoGenetics in the choroid plexus: integrated opto- and chemogenetic control in vivo. NEUROPHOTONICS 2024; 11:024210. [PMID: 38948888 PMCID: PMC11213259 DOI: 10.1117/1.nph.11.2.024210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Revised: 05/30/2024] [Accepted: 05/30/2024] [Indexed: 07/02/2024]
Abstract
Significance The choroid plexus (ChP) epithelial network displays diverse dynamics, including propagating calcium waves and individuated fluctuations in single cells. These rapid events underscore the possibility that ChP dynamics may reflect behaviorally relevant and clinically important changes in information processing and signaling. Optogenetic and chemogenetic tools provide spatiotemporally precise and sustained approaches for testing such dynamics in vivo. Here, we describe the feasibility of a novel combined opto- and chemogenetic tool, BioLuminescent-OptoGenetics (BL-OG), for the ChP in vivo. In the "LuMinOpsin" (LMO) BL-OG strategy, a luciferase is tethered to an adjacent optogenetic element. This molecule allows chemogenetic activation when the opsin is driven by light produced through luciferase binding a small molecule (luciferin) or by conventional optogenetic light sources and BL-OG report of activation through light production. Aim To test the viability of BL-OG/LMO for ChP control. Approach Using transgenic and Cre-directed targeting to the ChP, we expressed LMO3 (a Gaussia luciferase-VChR1 fusion), a highly effective construct in neural systems. In mice expressing LMO3 in ChP, we directly imaged BL light production following multiple routes of coelenterazine (CTZ: luciferin) administration using an implanted cannula system. We also used home-cage videography with Deep LabCut analysis to test for any impact of repeated CTZ administration on basic health and behavioral indices. Results Multiple routes of CTZ administration drove BL photon production, including intracerebroventricular, intravenous, and intraperitoneal injection. Intravenous administration resulted in fast "flash" kinetics that diminished in seconds to minutes, and intraperitoneal administration resulted in slow rising activity that sustained hours. Mice showed no consistent impact of 1 week of intraperitoneal CTZ administration on weight, drinking, motor behavior, or sleep/wake cycles. Conclusions BL-OG/LMO provides unique advantages for testing the role of ChP dynamics in biological processes.
Collapse
Affiliation(s)
- Eric Klein
- Brown University, Providence, Rhode Island, United States
| | - Sophie Marsh
- Brown University, Providence, Rhode Island, United States
| | - Jordan Becker
- Brown University, Providence, Rhode Island, United States
| | - Mark Andermann
- Beth Israel Deaconess Medical Center Harvard, Boston, Massachusetts, United States
| | - Maria Lehtinen
- Brown University, Providence, Rhode Island, United States
- Boston Children’s Hospital, Boston, Massachusetts, United States
| | | |
Collapse
|
4
|
Smiley CE, Pate BS, Bouknight SJ, Harrington EN, Jasnow AM, Wood SK. The role of locus coeruleus neuroimmune signaling in the response to social stress in female rats. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.10.575076. [PMID: 38260568 PMCID: PMC10802589 DOI: 10.1101/2024.01.10.575076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Neuropsychiatric disorders that result from stress exposure, including post-traumatic stress disorder and substance abuse, are highly associated with central inflammation. Our previous work established that females selectively exhibit increased proinflammatory cytokine release within the noradrenergic locus coeruleus (LC) in response to witnessing social stress, which was associated with a hypervigilant phenotype. Thus, neuroimmune activation in the LC may be responsible for the heightened risk of developing mental health disorders following stress in females. Further, ablation of microglia using pharmacological techniques reduces the hypervigilant behavioral response exhibited by females during social stress. Therefore, these studies were designed to further investigate the impact of stress-induced neuroimmune signaling on the long-term behavioral and neuronal consequences of social stress exposure in females using DREADDs. We first characterized the use of an AAV-CD68-Gi-DREADD virus targeted to microglia within the LC. While the use of AAVs in preclinical research has been limited by observations regarding poor transfection efficiency in mice, recent data suggest that species specific differences in microglial genetics may render rats more receptive to chemogenetic targeting of microglia using a CD68 promoter. Therefore, clozapine-n-oxide (CNO) was used to activate the microglial expressed hM4Di to inhibit microglial activity during acute exposure to vicarious social defeat (witness stress, WS) in female rats. Neuroimmune activity within the LC, quantified by microglial morphology and cytokine release, was augmented by WS and prevented by chemogenetic microglial inhibition. Following confirmation of DREADD selectivity and efficacy, we utilized this technique to inhibit microglial activity during repeated WS. Subsequently, rats were tested in a marble burying paradigm and exposed to the WS cues and context to measure hypervigilant behaviors. Chemogenetic-mediated inhibition of microglial activity prior to each WS exposure prevented both acute and long-term hypervigilant responses induced by WS across multiple behavioral paradigms. Further, a history of microglial inactivation during WS prevented the heightened LC activity typically observed in response to stress cues. These studies are among the first to use a chemogenetic approach to inhibit microglia within the female brain in vivo and establish LC inflammation as a key mechanism underlying the behavioral and neuronal responses to social stress in females.
Collapse
Affiliation(s)
- Cora E. Smiley
- Department of Pharmacology, Physiology, and Neuroscience; University of South Carolina School of Medicine, Columbia, SC 29209
- WJB Dorn Veterans Administration Medical Center, Columbia, SC 29209
| | - Brittany S. Pate
- Department of Pharmacology, Physiology, and Neuroscience; University of South Carolina School of Medicine, Columbia, SC 29209
- University of South Carolina, Department of Exercise Science, Columbia, SC 29209
| | - Samantha J. Bouknight
- Department of Pharmacology, Physiology, and Neuroscience; University of South Carolina School of Medicine, Columbia, SC 29209
| | - Evelynn N. Harrington
- Department of Pharmacology, Physiology, and Neuroscience; University of South Carolina School of Medicine, Columbia, SC 29209
- WJB Dorn Veterans Administration Medical Center, Columbia, SC 29209
| | - Aaron M. Jasnow
- Department of Pharmacology, Physiology, and Neuroscience; University of South Carolina School of Medicine, Columbia, SC 29209
| | - Susan K. Wood
- Department of Pharmacology, Physiology, and Neuroscience; University of South Carolina School of Medicine, Columbia, SC 29209
- WJB Dorn Veterans Administration Medical Center, Columbia, SC 29209
| |
Collapse
|
5
|
Aomine Y, Oyama Y, Sakurai K, Macpherson T, Ozawa T, Hikida T. Clozapine N-oxide, compound 21, and JHU37160 do not influence effortful reward-seeking behavior in mice. Psychopharmacology (Berl) 2024; 241:89-96. [PMID: 37792024 PMCID: PMC10774210 DOI: 10.1007/s00213-023-06465-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Accepted: 09/04/2023] [Indexed: 10/05/2023]
Abstract
RATIONALE Clozapine N-oxide (CNO) has been developed as a ligand to selectively activate designer receptors exclusively activated by designer drugs (DREADDs). However, previous studies have revealed that peripherally injected CNO is reverse-metabolized into clozapine, which, in addition to activating DREADDs, acts as an antagonist at various neurotransmitter receptors, suggesting potential off-target effects of CNO on animal physiology and behaviors. Recently, second-generation DREADD agonists compound 21 (C21) and JHU37160 (J60) have been developed, but their off-target effects are not fully understood. OBJECTIVES The present studies assessed the effect of novel DREADD ligands on reward-seeking behavior. METHODS We first tested the possible effect of acute i.p. injection of low-to-moderate (0.1, 0.3, 1, 3 mg/kg) of CNO, C21, and J60 on motivated reward-seeking behavior in wild-type mice. We then examined whether a high dose (10 mg/kg) of these drugs might be able to alter responding. RESULTS Low-to-moderate doses of all drugs and a high dose of CNO or C21 did not alter operant lick responding for a reward under a progressive ratio schedule of reinforcement, in which the number of operant lick responses to obtain a reward increases after each reward collection. However, high-dose J60 resulted in a total lack of responding that was later observed in an open field arena to be due to a sedative effect. CONCLUSIONS This study provides definitive evidence that commonly used doses of CNO, C21, and J60 have negligible off-target effects on motivated reward-seeking but urges caution when using high doses of J60 due to sedative effects.
Collapse
Affiliation(s)
- Yoshiatsu Aomine
- Laboratory for Advanced Brain Functions, Institute for Protein Research, Osaka University, Suita, Osaka, Japan
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka, Osaka, Japan
| | - Yoshinobu Oyama
- Laboratory for Advanced Brain Functions, Institute for Protein Research, Osaka University, Suita, Osaka, Japan
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka, Osaka, Japan
| | - Koki Sakurai
- Laboratory for Advanced Brain Functions, Institute for Protein Research, Osaka University, Suita, Osaka, Japan
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka, Osaka, Japan
- Laboratory of Protein Profiling and Functional Proteomics, Institute for Protein Research, Osaka University, Suita, Osaka, Japan
| | - Tom Macpherson
- Laboratory for Advanced Brain Functions, Institute for Protein Research, Osaka University, Suita, Osaka, Japan
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka, Osaka, Japan
| | - Takaaki Ozawa
- Laboratory for Advanced Brain Functions, Institute for Protein Research, Osaka University, Suita, Osaka, Japan.
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka, Osaka, Japan.
| | - Takatoshi Hikida
- Laboratory for Advanced Brain Functions, Institute for Protein Research, Osaka University, Suita, Osaka, Japan.
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka, Osaka, Japan.
| |
Collapse
|
6
|
Dheer A, Bosco DB, Zheng J, Wang L, Zhao S, Haruwaka K, Yi MH, Barath A, Tian DS, Wu LJ. Chemogenetic approaches reveal dual functions of microglia in seizures. Brain Behav Immun 2024; 115:406-418. [PMID: 37926132 PMCID: PMC10841657 DOI: 10.1016/j.bbi.2023.11.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 10/14/2023] [Accepted: 11/02/2023] [Indexed: 11/07/2023] Open
Abstract
Microglia are key players in maintaining brain homeostasis and exhibit phenotypic alterations in response to epileptic stimuli. However, it is still relatively unknown if these alterations are pro- or anti-epileptic. To unravel this dilemma, we employed chemogenetic manipulation of microglia using the artificial Gi-Dreadd receptor within a kainic acid (KA) induced murine seizure model. Our results indicate that acute Gi-Dreadd activation with Clozapine-N-Oxide can reduce seizure severity. Additionally, we observed increased interaction between microglia and neuronal soma, which correlated with reduced neuronal hyperactivity. Interestingly, prolonged activation of microglial Gi-Dreadds by repeated doses of CNO over 3 days, arrested microglia in a less active, homeostatic-like state, which associated with increased neuronal loss after KA induced seizures. RNAseq analysis revealed that prolonged activation of Gi-Dreadd interferes with interferon β signaling and microglia proliferation. Thus, our findings highlight the importance of microglial Gi signaling not only during status epilepticus (SE) but also within later seizure induced pathology.
Collapse
Affiliation(s)
- Aastha Dheer
- Department of Neurology, Mayo Clinic, Rochester, MN, USA
| | - Dale B Bosco
- Department of Neurology, Mayo Clinic, Rochester, MN, USA
| | - Jiaying Zheng
- Department of Neurology, Mayo Clinic, Rochester, MN, USA; Mayo Clinic Graduate School of Biomedical Sciences, Rochester, MN, USA
| | - Lingxiao Wang
- Department of Neurology, Mayo Clinic, Rochester, MN, USA; Mayo Clinic Graduate School of Biomedical Sciences, Rochester, MN, USA
| | - Shunyi Zhao
- Department of Neurology, Mayo Clinic, Rochester, MN, USA; Mayo Clinic Graduate School of Biomedical Sciences, Rochester, MN, USA
| | | | - Min-Hee Yi
- Department of Neurology, Mayo Clinic, Rochester, MN, USA
| | - Abhijeet Barath
- Department of Neurology, Mayo Clinic, Rochester, MN, USA; Mayo Clinic Graduate School of Biomedical Sciences, Rochester, MN, USA
| | - Dai-Shi Tian
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Long-Jun Wu
- Department of Neurology, Mayo Clinic, Rochester, MN, USA; Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA; Department of Immunology, Mayo Clinic, Rochester, MN, USA.
| |
Collapse
|
7
|
Lusk S, Ward CS, Chang A, Twitchell-Heyne A, Fattig S, Allen G, Jankowsky J, Ray R. An automated respiratory data pipeline for waveform characteristic analysis. J Physiol 2023; 601:4767-4806. [PMID: 37786382 PMCID: PMC10841337 DOI: 10.1113/jp284363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 08/11/2023] [Indexed: 10/04/2023] Open
Abstract
Comprehensive and accurate analysis of respiratory and metabolic data is crucial to modelling congenital, pathogenic and degenerative diseases converging on autonomic control failure. A lack of tools for high-throughput analysis of respiratory datasets remains a major challenge. We present Breathe Easy, a novel open-source pipeline for processing raw recordings and associated metadata into operative outcomes, publication-worthy graphs and robust statistical analyses including QQ and residual plots for assumption queries and data transformations. This pipeline uses a facile graphical user interface for uploading data files, setting waveform feature thresholds and defining experimental variables. Breathe Easy was validated against manual selection by experts, which represents the current standard in the field. We demonstrate Breathe Easy's utility by examining a 2-year longitudinal study of an Alzheimer's disease mouse model to assess contributions of forebrain pathology in disordered breathing. Whole body plethysmography has become an important experimental outcome measure for a variety of diseases with primary and secondary respiratory indications. Respiratory dysfunction, while not an initial symptom in many of these disorders, often drives disability or death in patient outcomes. Breathe Easy provides an open-source respiratory analysis tool for all respiratory datasets and represents a necessary improvement upon current analytical methods in the field. KEY POINTS: Respiratory dysfunction is a common endpoint for disability and mortality in many disorders throughout life. Whole body plethysmography in rodents represents a high face-value method for measuring respiratory outcomes in rodent models of these diseases and disorders. Analysis of key respiratory variables remains hindered by manual annotation and analysis that leads to low throughput results that often exclude a majority of the recorded data. Here we present a software suite, Breathe Easy, that automates the process of data selection from raw recordings derived from plethysmography experiments and the analysis of these data into operative outcomes and publication-worthy graphs with statistics. We validate Breathe Easy with a terabyte-scale Alzheimer's dataset that examines the effects of forebrain pathology on respiratory function over 2 years of degeneration.
Collapse
Affiliation(s)
- Savannah Lusk
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | - Christopher S. Ward
- Department of Integrative Physiology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Andersen Chang
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | | | - Shaun Fattig
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | - Genevera Allen
- Departments of Electrical and Computer Engineering, Statistics, and Computer Science, Rice University, Houston, TX 77030, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, TX 77030, USA
| | - Joanna Jankowsky
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
- Departments of Neurology, Neurosurgery, and Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Russell Ray
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
- McNair Medical Institute, Houston, TX 77030, USA
| |
Collapse
|
8
|
Chang Y, Hummel SN, Watson MN, Jin G, Lian XL, Bao X. Engineered Artificial Human Neutrophils Exhibit Mature Functional Performance. ACS Synth Biol 2023; 12:2262-2270. [PMID: 37523468 PMCID: PMC11070884 DOI: 10.1021/acssynbio.3c00309] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/02/2023]
Abstract
Neutrophils, a key innate immune component, are powerful effector leukocytes for mediating opposing effects on tumor progression and ameliorating pathogen infections. However, their short lifespan and complex purification process have limited neutrophil clinical applications. Here we combined genetic engineering technology with a nanodrug system to construct artificial neutrophils that display functions similar to those of native neutrophils. K562 and HL60 human leukemia cells were engineered to express the human G protein-coupled receptor hM4Di. Compared to the parental cells, engineered hM4Di-K562 and hM4Di-HL60 cells exhibited excellent chemotaxis ability towards clozapine-N-oxide (CNO) and superior bacteria phagocytic behavior, resembling native neutrophils. The antibacterial ability of the hM4Di-K562 cells was further enhanced by loading them with the glycopeptide vancomycin via mesoporous silica nanoparticles (Nano@Van). Our proposed artificial cell engineering platform provides a new avenue to investigate the physiological properties of neutrophils.
Collapse
Affiliation(s)
- Yun Chang
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, IN 47906, USA
- Purdue University Institute for Cancer Research, West Lafayette, IN 47906, USA
| | - Sydney N. Hummel
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, IN 47906, USA
| | - Monique N. Watson
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47906, USA
| | - Gyuhyung Jin
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, IN 47906, USA
- Purdue University Institute for Cancer Research, West Lafayette, IN 47906, USA
| | - Xiaojun Lance Lian
- Department of Biomedical Engineering, The Huck Institutes of the Life Sciences, Department of Biology, The Pennsylvania State University, University Park, PA 16802, USA
| | - Xiaoping Bao
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, IN 47906, USA
- Purdue University Institute for Cancer Research, West Lafayette, IN 47906, USA
| |
Collapse
|
9
|
Lawson KA, Ruiz CM, Mahler SV. A head-to-head comparison of two DREADD agonists for suppressing operant behavior in rats via VTA dopamine neuron inhibition. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.27.534429. [PMID: 37034819 PMCID: PMC10081263 DOI: 10.1101/2023.03.27.534429] [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] [Indexed: 06/19/2023]
Abstract
Rationale Designer receptors exclusively activated by designer drugs (DREADDs) are a tool for "remote control" of defined neuronal populations during behavior. These receptors are inert unless bound by an experimenter-administered designer drug, most commonly clozapine-n-oxide (CNO). However, questions have emerged about the suitability of CNO as a systemically administered DREADD agonist. Objectives Second-generation agonists such as JHU37160 (J60) have been developed, which may have more favorable properties than CNO. Here we sought to directly compare effects of CNO (0, 1, 5, & 10 mg/kg, i.p.) and J60 (0, 0.03, 0.3, & 3 mg/kg, i.p.) on operant food pursuit. Methods Male and female TH:Cre+ rats and their wildtype (WT) littermates received cre-dependent hM4Di-mCherry vector injections into ventral tegmental area (VTA), causing inhibitory DREADD expression in VTA dopamine neurons in TH:Cre+ rats. Rats were trained to stably lever press for palatable food on a fixed ratio 10 schedule, and doses of both agonists were tested on separate days in a counterbalanced order. Results All three CNO doses reduced operant food seeking in rats with DREADDs, and no CNO dose had behavioral effects in WT controls. The highest tested J60 dose significantly reduced responding in DREADD rats, but this dose also increased responding in WTs, indicating non-specific effects. The magnitude of CNO and J60 effects in TH:Cre+ rats were correlated and were present in both sexes. Conclusions Findings demonstrate the usefulness of directly comparing DREADD agonists when optimizing behavioral chemogenetics, and highlight the importance of proper controls, regardless of the DREADD agonist employed.
Collapse
Affiliation(s)
- Kate A Lawson
- Department of Neurobiology and Behavior, University of California Irvine, Irvine, CA USA
| | - Christina M Ruiz
- Department of Neurobiology and Behavior, University of California Irvine, Irvine, CA USA
| | - Stephen V Mahler
- Department of Neurobiology and Behavior, University of California Irvine, Irvine, CA USA
| |
Collapse
|
10
|
Galer EL, Huang R, Madhavan M, Wang E, Zhou Y, Leiter JC, Lu DC. Cervical Epidural Electrical Stimulation Increases Respiratory Activity through Somatostatin-Expressing Neurons in the Dorsal Cervical Spinal Cord in Rats. J Neurosci 2023; 43:419-432. [PMID: 36639888 PMCID: PMC9864577 DOI: 10.1523/jneurosci.1958-21.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 09/21/2022] [Accepted: 09/29/2022] [Indexed: 12/12/2022] Open
Abstract
We tested the hypothesis that dorsal cervical epidural electrical stimulation (CEES) increases respiratory activity in male and female anesthetized rats. Respiratory frequency and minute ventilation were significantly increased when CEES was applied dorsally to the C2-C6 region of the cervical spinal cord. By injecting pseudorabies virus into the diaphragm and using c-Fos activity to identify neurons activated during CEES, we found neurons in the dorsal horn of the cervical spinal cord in which c-Fos and pseudorabies were co-localized, and these neurons expressed somatostatin (SST). Using dual viral infection to express the inhibitory Designer Receptors Exclusively Activated by Designer Drugs (DREADD), hM4D(Gi), selectively in SST-positive cells, we inhibited SST-expressing neurons by administering Clozapine N-oxide (CNO). During CNO-mediated inhibition of SST-expressing cervical spinal neurons, the respiratory excitation elicited by CEES was diminished. Thus, dorsal cervical epidural stimulation activated SST-expressing neurons in the cervical spinal cord, likely interneurons, that communicated with the respiratory pattern generating network to effect changes in ventilation.SIGNIFICANCE STATEMENT A network of pontomedullary neurons within the brainstem generates respiratory behaviors that are susceptible to modulation by a variety of inputs; spinal sensory and motor circuits modulate and adapt this output to meet the demands placed on the respiratory system. We explored dorsal cervical epidural electrical stimulation (CEES) excitation of spinal circuits to increase ventilation in rats. We identified dorsal somatostatin (SST)-expressing neurons in the cervical spinal cord that were activated (c-Fos-positive) by CEES. CEES no longer stimulated ventilation during inhibition of SST-expressing spinal neuronal activity, thereby demonstrating that spinal SST neurons participate in the activation of respiratory circuits affected by CEES. This work establishes a mechanistic foundation to repurpose a clinically accessible neuromodulatory therapy to activate respiratory circuits and stimulate ventilation.
Collapse
Affiliation(s)
- Erika L Galer
- Department of Neurosurgery, University of California Los Angeles, Los Angeles 90095, California
- Department of Molecular Cellular and Integrative Physiology, University of California Los Angeles, Los Angeles 90095, California
| | - Ruyi Huang
- Department of Neurosurgery, University of California Los Angeles, Los Angeles 90095, California
| | - Meghna Madhavan
- Department of Neurosurgery, University of California Los Angeles, Los Angeles 90095, California
| | - Emily Wang
- Department of Neurosurgery, University of California Los Angeles, Los Angeles 90095, California
| | - Yan Zhou
- Department of Neurosurgery, University of California Los Angeles, Los Angeles 90095, California
| | - James C Leiter
- Department of Neurosurgery, University of California Los Angeles, Los Angeles 90095, California
- Research Service, White River Junction VA Medical Center, White River Junction 05009, Vermont
| | - Daniel C Lu
- Department of Neurosurgery, University of California Los Angeles, Los Angeles 90095, California
- Department of Molecular Cellular and Integrative Physiology, University of California Los Angeles, Los Angeles 90095, California
- Brain Research Institute, University of California Los Angeles, Los Angeles 90095, California
| |
Collapse
|
11
|
Silverman HA, Tynan A, Hepler TD, Chang EH, Gunasekaran M, Li JH, Huerta TS, Tsaava T, Chang Q, Addorisio ME, Chen AC, Thompson DA, Pavlov VA, Brines M, Tracey KJ, Chavan SS. Transient Receptor Potential Ankyrin-1-expressing vagus nerve fibers mediate IL-1β induced hypothermia and reflex anti-inflammatory responses. Mol Med 2023; 29:4. [PMID: 36650454 PMCID: PMC9847185 DOI: 10.1186/s10020-022-00590-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 12/11/2022] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND Inflammation, the physiological response to infection and injury, is coordinated by the immune and nervous systems. Interleukin-1β (IL-1β) and other cytokines produced during inflammatory responses activate sensory neurons (nociceptors) to mediate the onset of pain, sickness behavior, and metabolic responses. Although nociceptors expressing Transient Receptor Potential Ankyrin-1 (TRPA1) can initiate inflammation, comparatively little is known about the role of TRPA1 nociceptors in the physiological responses to specific cytokines. METHODS To monitor body temperature in conscious and unrestrained mice, telemetry probes were implanted into peritoneal cavity of mice. Using transgenic and tissue specific knockouts and chemogenetic techniques, we recorded temperature responses to the potent pro-inflammatory cytokine IL-1β. Using calcium imaging, whole cell patch clamping and whole nerve recordings, we investigated the role of TRPA1 during IL-1β-mediated neuronal activation. Mouse models of acute endotoxemia and sepsis were used to elucidate how specific activation, with optogenetics and chemogenetics, or ablation of TRPA1 neurons can affect the outcomes of inflammatory insults. All statistical tests were performed with GraphPad Prism 9 software and for all analyses, P ≤ 0.05 was considered statistically significant. RESULTS Here, we describe a previously unrecognized mechanism by which IL-1β activates afferent vagus nerve fibers to trigger hypothermia, a response which is abolished by selective silencing of neuronal TRPA1. Afferent vagus nerve TRPA1 signaling also inhibits endotoxin-stimulated cytokine storm and significantly reduces the lethality of bacterial sepsis. CONCLUSION Thus, IL-1β activates TRPA1 vagus nerve signaling in the afferent arm of a reflex anti-inflammatory response which inhibits cytokine release, induces hypothermia, and reduces the mortality of infection. This discovery establishes that TRPA1, an ion channel known previously as a pro-inflammatory detector of cold, pain, itch, and a wide variety of noxious molecules, also plays a specific anti-inflammatory role via activating reflex anti-inflammatory activity.
Collapse
Affiliation(s)
- Harold A Silverman
- Laboratory for Biomedical Sciences, Institute for Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Drive, Manhasset, NY, 11030, USA
| | - Aisling Tynan
- Laboratory for Biomedical Sciences, Institute for Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Drive, Manhasset, NY, 11030, USA
| | - Tyler D Hepler
- Laboratory for Biomedical Sciences, Institute for Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Drive, Manhasset, NY, 11030, USA
| | - Eric H Chang
- Laboratory for Biomedical Sciences, Institute for Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Drive, Manhasset, NY, 11030, USA
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, 500 Hofstra Blvd, Hempstead, NY, 11549, USA
- The Elmezzi Graduate School of Molecular Medicine, Northwell Health, 350 Community Drive, Manhasset, NY, 11030, USA
| | - Manojkumar Gunasekaran
- Laboratory for Biomedical Sciences, Institute for Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Drive, Manhasset, NY, 11030, USA
| | - Jian Hua Li
- Laboratory for Biomedical Sciences, Institute for Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Drive, Manhasset, NY, 11030, USA
| | - Tomás S Huerta
- Laboratory for Biomedical Sciences, Institute for Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Drive, Manhasset, NY, 11030, USA
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, 500 Hofstra Blvd, Hempstead, NY, 11549, USA
| | - Tea Tsaava
- Laboratory for Biomedical Sciences, Institute for Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Drive, Manhasset, NY, 11030, USA
| | - Qing Chang
- Laboratory for Biomedical Sciences, Institute for Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Drive, Manhasset, NY, 11030, USA
| | - Meghan E Addorisio
- Laboratory for Biomedical Sciences, Institute for Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Drive, Manhasset, NY, 11030, USA
| | - Adrian C Chen
- Laboratory for Biomedical Sciences, Institute for Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Drive, Manhasset, NY, 11030, USA
| | - Dane A Thompson
- Laboratory for Biomedical Sciences, Institute for Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Drive, Manhasset, NY, 11030, USA
- Department of Surgery, North Shore University Hospital, Northwell Health, 300 Community Drive, Manhasset, NY, 11030, USA
- The Elmezzi Graduate School of Molecular Medicine, Northwell Health, 350 Community Drive, Manhasset, NY, 11030, USA
| | - Valentin A Pavlov
- Laboratory for Biomedical Sciences, Institute for Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Drive, Manhasset, NY, 11030, USA
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, 500 Hofstra Blvd, Hempstead, NY, 11549, USA
- The Elmezzi Graduate School of Molecular Medicine, Northwell Health, 350 Community Drive, Manhasset, NY, 11030, USA
| | - Michael Brines
- Laboratory for Biomedical Sciences, Institute for Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Drive, Manhasset, NY, 11030, USA
| | - Kevin J Tracey
- Laboratory for Biomedical Sciences, Institute for Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Drive, Manhasset, NY, 11030, USA.
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, 500 Hofstra Blvd, Hempstead, NY, 11549, USA.
- The Elmezzi Graduate School of Molecular Medicine, Northwell Health, 350 Community Drive, Manhasset, NY, 11030, USA.
| | - Sangeeta S Chavan
- Laboratory for Biomedical Sciences, Institute for Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Drive, Manhasset, NY, 11030, USA.
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, 500 Hofstra Blvd, Hempstead, NY, 11549, USA.
- The Elmezzi Graduate School of Molecular Medicine, Northwell Health, 350 Community Drive, Manhasset, NY, 11030, USA.
| |
Collapse
|
12
|
Nebeling FC, Poll S, Justus LC, Steffen J, Keppler K, Mittag M, Fuhrmann M. Microglial motility is modulated by neuronal activity and correlates with dendritic spine plasticity in the hippocampus of awake mice. eLife 2023; 12:83176. [PMID: 36749020 PMCID: PMC9946443 DOI: 10.7554/elife.83176] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 02/03/2023] [Indexed: 02/08/2023] Open
Abstract
Microglia, the resident immune cells of the brain, play a complex role in health and disease. They actively survey the brain parenchyma by physically interacting with other cells and structurally shaping the brain. Yet, the mechanisms underlying microglial motility and significance for synapse stability, especially in the hippocampus during adulthood, remain widely unresolved. Here, we investigated the effect of neuronal activity on microglial motility and the implications for the formation and survival of dendritic spines on hippocampal CA1 neurons in vivo. We used repetitive two-photon in vivo imaging in the hippocampus of awake and anesthetized mice to simultaneously study the motility of microglia and their interaction with dendritic spines. We found that CA3 to CA1 input is sufficient to modulate microglial process motility. Simultaneously, more dendritic spines emerged in mice after awake compared to anesthetized imaging. Interestingly, the rate of microglial contacts with individual dendritic spines and dendrites was associated with the stability, removal, and emergence of dendritic spines. These results suggest that microglia might sense neuronal activity via neurotransmitter release and actively participate in synaptic rewiring of the hippocampal neural network during adulthood. Further, this study has profound relevance for hippocampal learning and memory processes.
Collapse
Affiliation(s)
| | - Stefanie Poll
- Neuroimmunology and Imaging Group, German Center for Neurodegenerative DiseasesBonnGermany
| | - Lena Christine Justus
- Neuroimmunology and Imaging Group, German Center for Neurodegenerative DiseasesBonnGermany
| | - Julia Steffen
- Neuroimmunology and Imaging Group, German Center for Neurodegenerative DiseasesBonnGermany
| | - Kevin Keppler
- Light Microscopy Facility, German Center for Neurodegenerative DiseasesBonnGermany
| | - Manuel Mittag
- Neuroimmunology and Imaging Group, German Center for Neurodegenerative DiseasesBonnGermany
| | - Martin Fuhrmann
- Neuroimmunology and Imaging Group, German Center for Neurodegenerative DiseasesBonnGermany
| |
Collapse
|
13
|
Singer ML, Rana S, Benevides ES, Barral BE, Byrne BJ, Fuller DD. Chemogenetic activation of hypoglossal motoneurons in a mouse model of Pompe disease. J Neurophysiol 2022; 128:1133-1142. [PMID: 35976060 PMCID: PMC9621710 DOI: 10.1152/jn.00026.2022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 08/15/2022] [Accepted: 08/16/2022] [Indexed: 11/22/2022] Open
Abstract
Pompe disease is a lysosomal storage disease resulting from absence or deficiency of acid α-glucosidase (GAA). Tongue-related disorders including dysarthria, dysphagia, and obstructive sleep apnea are common in Pompe disease. Our purpose was to determine if designer receptors exclusively activated by designer drugs (DREADDs) could be used to stimulate tongue motor output in a mouse model of Pompe disease. An adeno-associated virus serotype 9 (AAV9) encoding an excitatory DREADD (AAV9-hSyn-hM3D(Gq)-mCherry, 2.44 × 1010 vg) was administered to the posterior tongue of 5-7-wk-old Gaa null (Gaa-/-) mice. Lingual EMG responses to intraperitoneal injection of saline or a DREADD ligand (JHU37160-dihydrochloride, J60) were assessed 12 wk later during spontaneous breathing. Saline injection produced no consistent changes in lingual EMG. Following the DREADD ligand, there were statistically significant (P < 0.05) increases in both tonic and phasic inspiratory EMG activity recorded from the posterior tongue. Brainstem histology confirmed mCherry expression in hypoglossal (XII) motoneurons in all mice, thus verifying retrograde movement of the AAV9 vector. Morphologically, Gaa-/- XII motoneurons showed histological characteristics that are typical of Pompe disease, including an enlarged soma and vacuolization. We conclude that lingual delivery of AAV9 can be used to drive functional expression of DREADD in XII motoneurons in a mouse model of Pompe disease.NEW & NOTEWORTHY In a mouse model of Pompe disease, lingual injection of adeno-associated virus (AAV) serotype 9 encoding DREADD was histologically verified to produce transgene expression in hypoglossal motoneurons. Subsequent intraperitoneal delivery of a DREADD ligand stimulated tonic and phase tongue motor output.In a mouse model of Pompe disease, lingual injection of adeno-associated virus (AAV) serotype 9 encoding DREADD was histologically verified to produce transgene expression in hypoglossal motoneurons. Subsequent intravenous delivery of a DREADD ligand stimulated tonic and phase tongue motor output.
Collapse
Affiliation(s)
- Michele L Singer
- Rehabilitation Science PhD Program, University of Florida, Gainesville, Florida
- Department of Physical Therapy, University of Florida, Gainesville, Florida
- Breathing Research and Therapeutics Center, University of Florida, Gainesville, Florida
- McKnight Brain Institute, University of Florida, Gainesville, Florida
| | - Sabhya Rana
- Department of Physical Therapy, University of Florida, Gainesville, Florida
- Breathing Research and Therapeutics Center, University of Florida, Gainesville, Florida
- McKnight Brain Institute, University of Florida, Gainesville, Florida
| | - Ethan S Benevides
- Rehabilitation Science PhD Program, University of Florida, Gainesville, Florida
- Department of Physical Therapy, University of Florida, Gainesville, Florida
- Breathing Research and Therapeutics Center, University of Florida, Gainesville, Florida
- McKnight Brain Institute, University of Florida, Gainesville, Florida
| | - Brian E Barral
- Breathing Research and Therapeutics Center, University of Florida, Gainesville, Florida
- McKnight Brain Institute, University of Florida, Gainesville, Florida
| | - Barry J Byrne
- Department of Pediatrics, University of Florida, Gainesville, Florida
- Powell Gene Therapy Center, University of Florida, Gainesville, Florida
| | - David D Fuller
- Rehabilitation Science PhD Program, University of Florida, Gainesville, Florida
- Department of Physical Therapy, University of Florida, Gainesville, Florida
- Breathing Research and Therapeutics Center, University of Florida, Gainesville, Florida
- McKnight Brain Institute, University of Florida, Gainesville, Florida
| |
Collapse
|
14
|
Rodd ZA, Engleman EA, Truitt WA, Burke AR, Molosh AI, Bell RL, Hauser SR. CNO administration increases dopamine and glutamate in the medial prefrontal cortex of wistar rats: Further concerns for the validity of the CNO-activated DREADD procedure. Neuroscience 2022; 491:176-184. [DOI: 10.1016/j.neuroscience.2022.03.028] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 03/03/2022] [Accepted: 03/23/2022] [Indexed: 12/14/2022]
|
15
|
Lusk SJ, McKinney A, Hunt PJ, Fahey PG, Patel J, Chang A, Sun JJ, Martinez VK, Zhu PJ, Egbert JR, Allen G, Jiang X, Arenkiel BR, Tolias AS, Costa-Mattioli M, Ray RS. A CRISPR toolbox for generating intersectional genetic mouse models for functional, molecular, and anatomical circuit mapping. BMC Biol 2022; 20:28. [PMID: 35086530 PMCID: PMC8796356 DOI: 10.1186/s12915-022-01227-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Accepted: 01/06/2022] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND The functional understanding of genetic interaction networks and cellular mechanisms governing health and disease requires the dissection, and multifaceted study, of discrete cell subtypes in developing and adult animal models. Recombinase-driven expression of transgenic effector alleles represents a significant and powerful approach to delineate cell populations for functional, molecular, and anatomical studies. In addition to single recombinase systems, the expression of two recombinases in distinct, but partially overlapping, populations allows for more defined target expression. Although the application of this method is becoming increasingly popular, its experimental implementation has been broadly restricted to manipulations of a limited set of common alleles that are often commercially produced at great expense, with costs and technical challenges associated with production of intersectional mouse lines hindering customized approaches to many researchers. Here, we present a simplified CRISPR toolkit for rapid, inexpensive, and facile intersectional allele production. RESULTS Briefly, we produced 7 intersectional mouse lines using a dual recombinase system, one mouse line with a single recombinase system, and three embryonic stem (ES) cell lines that are designed to study the way functional, molecular, and anatomical features relate to each other in building circuits that underlie physiology and behavior. As a proof-of-principle, we applied three of these lines to different neuronal populations for anatomical mapping and functional in vivo investigation of respiratory control. We also generated a mouse line with a single recombinase-responsive allele that controls the expression of the calcium sensor Twitch-2B. This mouse line was applied globally to study the effects of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) on calcium release in the ovarian follicle. CONCLUSIONS The lines presented here are representative examples of outcomes possible with the successful application of our genetic toolkit for the facile development of diverse, modifiable animal models. This toolkit will allow labs to create single or dual recombinase effector lines easily for any cell population or subpopulation of interest when paired with the appropriate Cre and FLP recombinase mouse lines or viral vectors. We have made our tools and derivative intersectional mouse and ES cell lines openly available for non-commercial use through publicly curated repositories for plasmid DNA, ES cells, and transgenic mouse lines.
Collapse
Affiliation(s)
- Savannah J Lusk
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Andrew McKinney
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Patrick J Hunt
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Paul G Fahey
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Jay Patel
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Andersen Chang
- Department of Statistics, Rice University, Houston, TX, USA
| | - Jenny J Sun
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Vena K Martinez
- Department of Pharmacology, Baylor College of Medicine, Houston, TX, USA
| | - Ping Jun Zhu
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Jeremy R Egbert
- Department of Cell Biology, University of Connecticut, Farmington, CT, USA
| | - Genevera Allen
- Department of Statistics, Computer Science, and Electrical and Computer Engineering, Rice University, Houston, TX, USA
- Neurological Research Institute, Baylor College of Medicine, Houston, TX, USA
| | - Xiaolong Jiang
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Benjamin R Arenkiel
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
- McNair Medical Institute, Houston, TX, USA
| | - Andreas S Tolias
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | | | - Russell S Ray
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA.
- McNair Medical Institute, Houston, TX, USA.
| |
Collapse
|
16
|
Shen Y, Luchetti A, Fernandes G, Do Heo W, Silva AJ. The emergence of molecular systems neuroscience. Mol Brain 2022; 15:7. [PMID: 34983613 PMCID: PMC8728933 DOI: 10.1186/s13041-021-00885-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 12/03/2021] [Indexed: 12/18/2022] Open
Abstract
Systems neuroscience is focused on how ensemble properties in the brain, such as the activity of neuronal circuits, gives rise to internal brain states and behavior. Many of the studies in this field have traditionally involved electrophysiological recordings and computational approaches that attempt to decode how the brain transforms inputs into functional outputs. More recently, systems neuroscience has received an infusion of approaches and techniques that allow the manipulation (e.g., optogenetics, chemogenetics) and imaging (e.g., two-photon imaging, head mounted fluorescent microscopes) of neurons, neurocircuits, their inputs and outputs. Here, we will review novel approaches that allow the manipulation and imaging of specific molecular mechanisms in specific cells (not just neurons), cell ensembles and brain regions. These molecular approaches, with the specificity and temporal resolution appropriate for systems studies, promise to infuse the field with novel ideas, emphases and directions, and are motivating the emergence of a molecularly oriented systems neuroscience, a new discipline that studies how the spatial and temporal patterns of molecular systems modulate circuits and brain networks, and consequently shape the properties of brain states and behavior.
Collapse
Affiliation(s)
- Yang Shen
- Departments of Neurobiology, Psychiatry and Biobehavioral Sciences, and Psychology, Integrative Center for Learning and Memory, and Brain Research Institute, UCLA, Los Angeles, CA, USA
| | - Alessandro Luchetti
- Departments of Neurobiology, Psychiatry and Biobehavioral Sciences, and Psychology, Integrative Center for Learning and Memory, and Brain Research Institute, UCLA, Los Angeles, CA, USA
| | - Giselle Fernandes
- Departments of Neurobiology, Psychiatry and Biobehavioral Sciences, and Psychology, Integrative Center for Learning and Memory, and Brain Research Institute, UCLA, Los Angeles, CA, USA
| | - Won Do Heo
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Alcino J Silva
- Departments of Neurobiology, Psychiatry and Biobehavioral Sciences, and Psychology, Integrative Center for Learning and Memory, and Brain Research Institute, UCLA, Los Angeles, CA, USA.
| |
Collapse
|
17
|
Experience-dependent myelination following stress is mediated by the neuropeptide dynorphin. Neuron 2021; 109:3619-3632.e5. [PMID: 34536353 DOI: 10.1016/j.neuron.2021.08.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 07/14/2021] [Accepted: 08/13/2021] [Indexed: 11/22/2022]
Abstract
Emerging evidence implicates experience-dependent myelination in learning and memory. However, the specific signals underlying this process remain unresolved. We demonstrate that the neuropeptide dynorphin, which is released from neurons upon high levels of activity, promotes experience-dependent myelination. Following forced swim stress, an experience that induces striatal dynorphin release, we observe increased striatal oligodendrocyte precursor cell (OPC) differentiation and myelination, which is abolished by deleting dynorphin or blocking its endogenous receptor, kappa opioid receptor (KOR). We find that dynorphin also promotes developmental OPC differentiation and myelination and demonstrate that this effect requires KOR expression specifically in OPCs. We characterize dynorphin-expressing neurons and use genetic sparse labeling to trace their axonal projections. Surprisingly, we find that they are unmyelinated normally and following forced swim stress. We propose a new model whereby experience-dependent and developmental myelination is mediated by unmyelinated, neuropeptide-expressing neurons that promote OPC differentiation for the myelination of neighboring axons.
Collapse
|
18
|
Developmental Shifts in Amygdala Activity during a High Social Drive State. J Neurosci 2021; 41:9308-9325. [PMID: 34611026 DOI: 10.1523/jneurosci.1414-21.2021] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 08/27/2021] [Accepted: 09/20/2021] [Indexed: 12/24/2022] Open
Abstract
Amygdala abnormalities characterize several psychiatric disorders with prominent social deficits and often emerge during adolescence. The basolateral amygdala (BLA) bidirectionally modulates social behavior and has increased sensitivity during adolescence. We tested how an environmentally-driven social state is regulated by the BLA in adults and adolescent male rats. We found that a high social drive state caused by brief social isolation increases age-specific social behaviors and increased BLA neuronal activity. Chemogenetic inactivation of BLA decreased the effect of high social drive on social engagement. High social drive preferentially enhanced BLA activity during social engagement; however, the effect of social opportunity on BLA activity was greater during adolescence. While this identifies a substrate underlying age differences in social drive, we then determined that high social drive increased BLA NMDA GluN2B expression and sensitivity to antagonism increased with age. Further, the effect of a high social drive state on BLA activity during social engagement was diminished by GluN2B blockade in an age-dependent manner. These results demonstrate the necessity of the BLA for environmentally driven social behavior, its sensitivity to social opportunity, and uncover a maturing role for BLA and its GluN2B receptors in social engagement.SIGNIFICANCE STATEMENT Social engagement during adolescence is a key component of healthy development. Social drive provides the impetus for social engagement and abnormalities underlie social symptoms of depression and anxiety. While adolescence is characterized by transitions in social drive and social environment sensitivity, little is known about the neural basis for these changes. We found that amygdala activity is uniquely sensitive to social environment during adolescence compared with adulthood, and is required for expression of heightened social drive. In addition, the neural substrates shift toward NMDA dependence in adulthood. These results are the first to demonstrate a unique neural signature of higher social drive and begin to uncover the underlying factors that heighten social engagement during adolescence.
Collapse
|
19
|
Sugimoto M, Takahashi Y, Sugimura YK, Tokunaga R, Yajima M, Kato F. Active role of the central amygdala in widespread mechanical sensitization in rats with facial inflammatory pain. Pain 2021; 162:2273-2286. [PMID: 33900711 PMCID: PMC8280967 DOI: 10.1097/j.pain.0000000000002224] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 01/01/2021] [Accepted: 01/26/2021] [Indexed: 01/19/2023]
Abstract
ABSTRACT Widespread or ectopic sensitization is a hallmark symptom of chronic pain, characterized by aberrantly enhanced pain sensitivity in multiple body regions remote from the site of original injury or inflammation. The central mechanism underlying widespread sensitization remains unidentified. The central nucleus of the amygdala (also called the central amygdala, CeA) is well situated for this role because it receives nociceptive information from diverse body sites and modulates pain sensitivity in various body regions. In this study, we examined the role of the CeA in a novel model of ectopic sensitization of rats. Injection of formalin into the left upper lip resulted in latent bilateral sensitization in the hind paw lasting >13 days in male Wistar rats. Chemogenetic inhibition of gamma-aminobutyric acid-ergic neurons or blockade of calcitonin gene-related peptide receptors in the right CeA, but not in the left, significantly attenuated this sensitization. Furthermore, chemogenetic excitation of gamma-aminobutyric acid-ergic neurons in the right CeA induced de novo bilateral hind paw sensitization in the rats without inflammation. These results indicate that the CeA neuronal activity determines hind paw tactile sensitivity in rats with remote inflammatory pain. They also suggest that the hind paw sensitization used in a large number of preclinical studies might not be simply a sign of the pain at the site of injury but rather a representation of the augmented CeA activity resulting from inflammation/pain in any part of the body or from activities of other brain regions, which has an active role of promoting defensive/protective behaviors to avoid further bodily damage.
Collapse
Affiliation(s)
- Mariko Sugimoto
- Center for Neuroscience of Pain and Department of Neuroscience, The Jikei University School of Medicine, Tokyo, Japan
- Department of Anesthesiology, Teikyo University School of Medicine, Tokyo, Japan
| | - Yukari Takahashi
- Center for Neuroscience of Pain and Department of Neuroscience, The Jikei University School of Medicine, Tokyo, Japan
| | - Yae K. Sugimura
- Center for Neuroscience of Pain and Department of Neuroscience, The Jikei University School of Medicine, Tokyo, Japan
| | - Ryota Tokunaga
- Center for Neuroscience of Pain and Department of Neuroscience, The Jikei University School of Medicine, Tokyo, Japan
| | - Manami Yajima
- Center for Neuroscience of Pain and Department of Neuroscience, The Jikei University School of Medicine, Tokyo, Japan
- Department of Dental Anesthesiology, School of Dental Medicine, Tsurumi University, Yokohama, Japan
| | - Fusao Kato
- Center for Neuroscience of Pain and Department of Neuroscience, The Jikei University School of Medicine, Tokyo, Japan
| |
Collapse
|
20
|
Yu H, Shi L, Chen J, Jun S, Hao Y, Wang S, Fu C, Zhang X, Lu H, Wang S, Yuan F. A Neural Circuit Mechanism Controlling Breathing by Leptin in the Nucleus Tractus Solitarii. Neurosci Bull 2021; 38:149-165. [PMID: 34212297 PMCID: PMC8821766 DOI: 10.1007/s12264-021-00742-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 05/07/2021] [Indexed: 02/03/2023] Open
Abstract
Leptin, an adipocyte-derived peptide hormone, has been shown to facilitate breathing. However, the central sites and circuit mechanisms underlying the respiratory effects of leptin remain incompletely understood. The present study aimed to address whether neurons expressing leptin receptor b (LepRb) in the nucleus tractus solitarii (NTS) contribute to respiratory control. Both chemogenetic and optogenetic stimulation of LepRb-expressing NTS (NTSLepRb) neurons notably activated breathing. Moreover, stimulation of NTSLepRb neurons projecting to the lateral parabrachial nucleus (LPBN) not only remarkably increased basal ventilation to a level similar to that of the stimulation of all NTSLepRb neurons, but also activated LPBN neurons projecting to the preBötzinger complex (preBötC). By contrast, ablation of NTSLepRb neurons projecting to the LPBN notably eliminated the enhanced respiratory effect induced by NTSLepRb neuron stimulation. In brainstem slices, bath application of leptin rapidly depolarized the membrane potential, increased the spontaneous firing rate, and accelerated the Ca2+ transients in most NTSLepRb neurons. Therefore, leptin potentiates breathing in the NTS most likely via an NTS-LPBN-preBötC circuit.
Collapse
Affiliation(s)
- Hongxiao Yu
- grid.256883.20000 0004 1760 8442Department of Physiology, Hebei Medical University, Shijiazhuang, 050017 Hebei China
| | - Luo Shi
- grid.256883.20000 0004 1760 8442Department of Physiology, Hebei Medical University, Shijiazhuang, 050017 Hebei China
| | - Jinting Chen
- grid.256883.20000 0004 1760 8442Core Facilities and Centers, Institute of Medicine and Health, Hebei Medical University, Shijiazhuang, 050017 Hebei China
| | - Shirui Jun
- grid.256883.20000 0004 1760 8442Department of Physiology, Hebei Medical University, Shijiazhuang, 050017 Hebei China
| | - Yinchao Hao
- grid.256883.20000 0004 1760 8442Department of Physiology, Hebei Medical University, Shijiazhuang, 050017 Hebei China
| | - Shuang Wang
- grid.256883.20000 0004 1760 8442Department of Physiology, Hebei Medical University, Shijiazhuang, 050017 Hebei China
| | - Congrui Fu
- grid.256883.20000 0004 1760 8442School of Nursing, Hebei Medical University, Shijiazhuang, 050000 Hebei China
| | - Xiang Zhang
- grid.256883.20000 0004 1760 8442Department of Physiology, Hebei Medical University, Shijiazhuang, 050017 Hebei China
| | - Haiyan Lu
- grid.256883.20000 0004 1760 8442Department of Orthodontics, College of Stomatology, Hebei Medical University, Shijiazhuang, 050017 Hebei China
| | - Sheng Wang
- grid.256883.20000 0004 1760 8442Department of Physiology, Hebei Medical University, Shijiazhuang, 050017 Hebei China ,Hebei Key Laboratory of Neurophysiology, Shijiazhuang, 050017 Hebei China
| | - Fang Yuan
- grid.256883.20000 0004 1760 8442Department of Physiology, Hebei Medical University, Shijiazhuang, 050017 Hebei China ,Hebei Key Laboratory of Neurophysiology, Shijiazhuang, 050017 Hebei China
| |
Collapse
|
21
|
Oligophrenin-1 moderates behavioral responses to stress by regulating parvalbumin interneuron activity in the medial prefrontal cortex. Neuron 2021; 109:1636-1656.e8. [PMID: 33831348 DOI: 10.1016/j.neuron.2021.03.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 02/09/2021] [Accepted: 03/10/2021] [Indexed: 12/28/2022]
Abstract
Ample evidence indicates that individuals with intellectual disability (ID) are at increased risk of developing stress-related behavioral problems and mood disorders, yet a mechanistic explanation for such a link remains largely elusive. Here, we focused on characterizing the syndromic ID gene oligophrenin-1 (OPHN1). We find that Ophn1 deficiency in mice markedly enhances helpless/depressive-like behavior in the face of repeated/uncontrollable stress. Strikingly, Ophn1 deletion exclusively in parvalbumin (PV) interneurons in the prelimbic medial prefrontal cortex (PL-mPFC) is sufficient to induce helplessness. This behavioral phenotype is mediated by a diminished excitatory drive onto Ophn1-deficient PL-mPFC PV interneurons, leading to hyperactivity in this region. Importantly, suppressing neuronal activity or RhoA/Rho-kinase signaling in the PL-mPFC reverses helpless behavior. Our results identify OPHN1 as a critical regulator of adaptive behavioral responses to stress and shed light onto the mechanistic links among OPHN1 genetic deficits, mPFC circuit dysfunction, and abnormalities in stress-related behaviors.
Collapse
|
22
|
Meister J, Wang L, Pydi SP, Wess J. Chemogenetic approaches to identify metabolically important GPCR signaling pathways: Therapeutic implications. J Neurochem 2021; 158:603-620. [PMID: 33540469 DOI: 10.1111/jnc.15314] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 01/21/2021] [Accepted: 01/29/2021] [Indexed: 12/16/2022]
Abstract
DREADDs (Designer Receptors Exclusively Activated by a Designer Drug) are designer G protein-coupled receptors (GPCRs) that are widely used in the neuroscience field to modulate neuronal activity. In this review, we will focus on DREADD studies carried out with genetically engineered mice aimed at elucidating signaling pathways important for maintaining proper glucose and energy homeostasis. The availability of muscarinic receptor-based DREADDs endowed with selectivity for one of the four major classes of heterotrimeric G proteins (Gs , Gi , Gq , and G12 ) has been instrumental in dissecting the physiological and pathophysiological roles of distinct G protein signaling pathways in metabolically important cell types. The novel insights gained from this work should inform the development of novel classes of drugs useful for the treatment of several metabolic disorders including type 2 diabetes and obesity.
Collapse
Affiliation(s)
- Jaroslawna Meister
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, USA
| | - Lei Wang
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, USA
| | - Sai P Pydi
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, USA
| | - Jürgen Wess
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, USA
| |
Collapse
|
23
|
Zhou Y, Yan E, Cheng D, Zhu H, Liu Z, Chen X, Ma L, Liu X. The Projection From Ventral CA1, Not Prefrontal Cortex, to Nucleus Accumbens Core Mediates Recent Memory Retrieval of Cocaine-Conditioned Place Preference. Front Behav Neurosci 2020; 14:558074. [PMID: 33304246 PMCID: PMC7701212 DOI: 10.3389/fnbeh.2020.558074] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 10/15/2020] [Indexed: 01/15/2023] Open
Abstract
Drug-paired cues inducing memory retrieval by expressing drug-seeking behaviors present a major challenge to drug abstinence. How neural circuits coordinate for drug memory retrieval remains unclear. Here, we report that exposure of the training chamber where cocaine-conditioned place preference (CPP) was performed increased neuronal activity in the core of nucleus accumbens (AcbC), ventral CA1 (vCA1), and medial prefrontal cortex (mPFC), as shown by elevated pERK and c-Fos levels. Chemogenetic inhibition of neuronal activity in the vCA1 and AcbC, but not mPFC, reduced the time spent in the cocaine-paired compartment, suggesting that the vCA1 and AcbC are required for the retrieval of cocaine-CPP memory and are key nodes recruited for cocaine memory storage. Furthermore, chemogenetic inhibition of the AcbC-projecting vCA1 neurons, but not the AcbC-projecting mPFC neurons, decreased the expression of cocaine-CPP. Optogenetic inhibition of the vCA1–AcbC projection, but not the mPFC–AcbC projection, also reduced the preference for the cocaine-paired compartment. Taken together, the cue-induced natural recall of cocaine memory depends on vCA1–AcbC circuits. The connectivity from the vCA1 to the AcbC may store the information of the cue–cocaine reward association critically required for memory retrieval. These data thus provide insights into the neural circuit basis of retrieval of drug-related memory.
Collapse
Affiliation(s)
- Yiming Zhou
- The State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, School of Basic Medical Sciences and the Institutes of Brain Science, Fudan University, Shanghai, China
| | - Enhui Yan
- The State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, School of Basic Medical Sciences and the Institutes of Brain Science, Fudan University, Shanghai, China
| | - Deqin Cheng
- The State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, School of Basic Medical Sciences and the Institutes of Brain Science, Fudan University, Shanghai, China
| | - Huiwen Zhu
- The State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, School of Basic Medical Sciences and the Institutes of Brain Science, Fudan University, Shanghai, China
| | - Zhiyuan Liu
- The State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, School of Basic Medical Sciences and the Institutes of Brain Science, Fudan University, Shanghai, China
| | - Xi Chen
- The State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, School of Basic Medical Sciences and the Institutes of Brain Science, Fudan University, Shanghai, China
| | - Lan Ma
- The State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, School of Basic Medical Sciences and the Institutes of Brain Science, Fudan University, Shanghai, China
| | - Xing Liu
- The State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, School of Basic Medical Sciences and the Institutes of Brain Science, Fudan University, Shanghai, China
| |
Collapse
|
24
|
Smith LC, Kimbrough A. Leveraging Neural Networks in Preclinical Alcohol Research. Brain Sci 2020; 10:E578. [PMID: 32825739 PMCID: PMC7565429 DOI: 10.3390/brainsci10090578] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Revised: 08/17/2020] [Accepted: 08/18/2020] [Indexed: 12/25/2022] Open
Abstract
Alcohol use disorder is a pervasive healthcare issue with significant socioeconomic consequences. There is a plethora of neural imaging techniques available at the clinical and preclinical level, including magnetic resonance imaging and three-dimensional (3D) tissue imaging techniques. Network-based approaches can be applied to imaging data to create neural networks that model the functional and structural connectivity of the brain. These networks can be used to changes to brain-wide neural signaling caused by brain states associated with alcohol use. Neural networks can be further used to identify key brain regions or neural "hubs" involved in alcohol drinking. Here, we briefly review the current imaging and neurocircuit manipulation methods. Then, we discuss clinical and preclinical studies using network-based approaches related to substance use disorders and alcohol drinking. Finally, we discuss how preclinical 3D imaging in combination with network approaches can be applied alone and in combination with other approaches to better understand alcohol drinking.
Collapse
Affiliation(s)
- Lauren C. Smith
- Department of Psychiatry, School of Medicine, University of California San Diego, MC 0667, La Jolla, CA 92093, USA;
| | - Adam Kimbrough
- Department of Psychiatry, School of Medicine, University of California San Diego, MC 0667, La Jolla, CA 92093, USA;
- Department of Basic Medical Sciences, College of Veterinary Medicine, Purdue University, 625 Harrison Street, West Lafayette, IN 47907, USA
| |
Collapse
|
25
|
Ung K, Tepe B, Pekarek B, Arenkiel BR, Deneen B. Parallel astrocyte calcium signaling modulates olfactory bulb responses. J Neurosci Res 2020; 98:1605-1618. [PMID: 32426930 PMCID: PMC8147697 DOI: 10.1002/jnr.24634] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 03/27/2020] [Accepted: 04/10/2020] [Indexed: 12/17/2022]
Abstract
Astrocytes are the most abundant glial cell in the central nervous system. They modulate synaptic function through a variety of mechanisms, and yet remain relatively understudied with respect to overall neuronal circuit function. Exploiting the tractability of the mouse olfactory system, we manipulated astrocyte activity and examined how astrocytes modulate olfactory bulb responses. Toward this, we genetically targeted both astrocytes and neurons for in vivo widefield imaging of Ca2+ responses to odor stimuli. We found that astrocytes exhibited odor response maps that overlap with excitatory neuronal activity. By manipulating Ca2+ activity in astrocytes using chemical genetics we found that odor-evoked neuronal activity was reciprocally affected, suggesting that astrocyte activation inhibits neuronal odor responses. Subsequently, behavioral experiments revealed that astrocyte manipulations affect both odor detection threshold and discrimination, suggesting that astrocytes play an active role in olfactory sensory processing circuits. Together, these studies show that astrocyte calcium signaling contributes to olfactory behavior through modulation of sensory circuits.
Collapse
Affiliation(s)
- Kevin Ung
- Program in Developmental Biology, Houston, TX 77030, USA
| | - Burak Tepe
- Program in Developmental Biology, Houston, TX 77030, USA
| | - Brandon Pekarek
- Department of Molecular and Human Genetics, Houston, TX 77030, USA
| | - Benjamin R. Arenkiel
- Program in Developmental Biology, Houston, TX 77030, USA
- Department of Molecular and Human Genetics, Houston, TX 77030, USA
- Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital, Houston, TX 77030, USA
| | - Benjamin Deneen
- Program in Developmental Biology, Houston, TX 77030, USA
- Center for Cell and Gene Therapy, Houston, TX 77030, USA
- Department of Neurosurgery, Baylor College of Medicine, Houston, TX 77030, USA
| |
Collapse
|
26
|
Sunshine MD, Sutor TW, Fox EJ, Fuller DD. Targeted activation of spinal respiratory neural circuits. Exp Neurol 2020; 328:113256. [PMID: 32087253 DOI: 10.1016/j.expneurol.2020.113256] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 01/31/2020] [Accepted: 02/18/2020] [Indexed: 12/30/2022]
Abstract
Spinal interneurons which discharge in phase with the respiratory cycle have been repeatedly described over the last 50 years. These spinal respiratory interneurons are part of a complex propriospinal network that is synaptically coupled with respiratory motoneurons. This article summarizes current knowledge regarding spinal respiratory interneurons and emphasizes chemical, electrical and physiological methods for activating spinal respiratory neural circuits. Collectively, the work reviewed here shows that activating spinal interneurons can have a powerful impact on spinal respiratory motor output, and can even drive rhythmic bursting in respiratory motoneuron pools under certain conditions. We propose that the primary functions of spinal respiratory neurons include 1) shaping the respiratory pattern into the final efferent motor output from the spinal respiratory nerves; 2) coordinating respiratory muscle activation across the spinal neuraxis; 3) coordinating postural, locomotor and respiratory movements, and 4) enabling plasticity of respiratory motor output in health and disease.
Collapse
Affiliation(s)
- Michael D Sunshine
- Department of Physical Therapy, University of Florida, United States of America; McKnight Brain Institute, University of Florida, United States of America; Rehabilitation Science PhD Program, University of Florida, United States of America; Center for Respiratory Research and Rehabilitation, University of Florida, United States of America
| | - Tommy W Sutor
- Department of Physical Therapy, University of Florida, United States of America; Rehabilitation Science PhD Program, University of Florida, United States of America; Center for Respiratory Research and Rehabilitation, University of Florida, United States of America
| | - Emily J Fox
- Department of Physical Therapy, University of Florida, United States of America; Center for Respiratory Research and Rehabilitation, University of Florida, United States of America; Clinical Research Center, Brooks Rehabilitation, Jacksonville, FL, United States of America
| | - David D Fuller
- Department of Physical Therapy, University of Florida, United States of America; McKnight Brain Institute, University of Florida, United States of America; Center for Respiratory Research and Rehabilitation, University of Florida, United States of America.
| |
Collapse
|
27
|
Caron A, Reynolds RP, Castorena CM, Michael NJ, Lee CE, Lee S, Berdeaux R, Scherer PE, Elmquist JK. Adipocyte Gs but not Gi signaling regulates whole-body glucose homeostasis. Mol Metab 2019; 27:11-21. [PMID: 31279640 PMCID: PMC6717754 DOI: 10.1016/j.molmet.2019.06.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 06/20/2019] [Accepted: 06/20/2019] [Indexed: 01/24/2023] Open
Abstract
Objective The sympathetic nervous system (SNS) is a key regulator of the metabolic and endocrine functions of adipose tissue. Increased SNS outflow promotes fat mobilization, stimulates non-shivering thermogenesis, promotes browning, and inhibits leptin production. Most of these effects are attributed to norepinephrine activation of the Gs-coupled beta adrenergic receptors located on the surface of the adipocytes. Evidence suggests that other adrenergic receptor subtypes, including the Gi-coupled alpha 2 adrenergic receptors might also mediate the SNS effects on adipose tissue. However, the impact of acute stimulation of adipocyte Gs and Gi has never been reported. Methods We harness the power of chemogenetics to develop unique mouse models allowing the specific and spatiotemporal stimulation of adipose tissue Gi and Gs signaling. We evaluated the impact of chemogenetic stimulation of these pathways on glucose homeostasis, lipolysis, leptin production, and gene expression. Results Stimulation of Gs signaling in adipocytes induced rapid and sustained hypoglycemia. These hypoglycemic effects were secondary to increased insulin release, likely consequent to increased lipolysis. Notably, we also observed differences in gene regulation and ex vivo lipolysis in different adipose depots. In contrast, acute stimulation of Gi signaling in adipose tissue did not affect glucose metabolism or lipolysis, but regulated leptin production. Conclusion Our data highlight the significance of adipose Gs signaling in regulating systemic glucose homeostasis. We also found previously unappreciated heterogeneity across adipose depots following acute stimulation. Together, these results highlight the complex interactions of GPCR signaling in adipose tissue and demonstrate the usefulness of chemogenetic technology to better understand adipocyte function. Chemogenetic stimulation of Gs signaling in adipose tissue potently induces hypoglycemia in mice. The magnitude by which adipose Gs stimulation reduces blood glucose is similar to the hypoglycemic effects of insulin. Chemogenetic stimulation of Gs signaling in adipose tissue ex vivo stimulates lipolysis. Chemogenetic stimulation of adipose Gi signaling does not affect glycemia or lipolysis, but increases leptin levels. Our data demonstrate the usefulness of chemogenetic technology to understand adipocytes functions.
Collapse
Affiliation(s)
- Alexandre Caron
- Department of Internal Medicine, Division of Hypothalamic Research, University of Texas Southwestern Medical Center, Dallas, TX, USA.
| | - Ryan P Reynolds
- Department of Internal Medicine, Division of Hypothalamic Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Carlos M Castorena
- Department of Internal Medicine, Division of Hypothalamic Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Natalie J Michael
- Department of Internal Medicine, Division of Hypothalamic Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Charlotte E Lee
- Department of Internal Medicine, Division of Hypothalamic Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Syann Lee
- Department of Internal Medicine, Division of Hypothalamic Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Rebecca Berdeaux
- Department of Integrative Biology and Pharmacology, Center for Metabolic and Degenerative Diseases at the Brown Foundation, Institute of Molecular Medicine, McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth), Graduate Program in Biochemistry and Cell Biology, MD Anderson Cancer Center-UTHealth Graduate School of Biomedical Sciences, Houston, TX, USA
| | - Philipp E Scherer
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Joel K Elmquist
- Department of Internal Medicine, Division of Hypothalamic Research, University of Texas Southwestern Medical Center, Dallas, TX, USA.
| |
Collapse
|