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Tractenberg SG, Reinhard SM, Sathyanesan A. Editorial: Neurodevelopment: parental influences, in utero exposures, and genetics. Front Neurosci 2024; 17:1331453. [PMID: 38249590 PMCID: PMC10797071 DOI: 10.3389/fnins.2023.1331453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 12/11/2023] [Indexed: 01/23/2024] Open
Affiliation(s)
| | - Sarah Marie Reinhard
- Department of Psychology, Human Arts and Social Sciences, Cabrillo College, Aptos, CA, United States
| | - Aaron Sathyanesan
- Department of Biology, College of Arts and Science, University of Dayton, Dayton, OH, United States
- Department of Electrical and Computer Engineering, School of Engineering, University of Dayton, Dayton, OH, United States
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Kratimenos P, Vij A, Vidva R, Koutroulis I, Delivoria-Papadopoulos M, Gallo V, Sathyanesan A. Computational analysis of cortical neuronal excitotoxicity in a large animal model of neonatal brain injury. J Neurodev Disord 2022; 14:26. [PMID: 35351004 PMCID: PMC8966144 DOI: 10.1186/s11689-022-09431-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 02/23/2022] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Neonatal hypoxic brain injury is a major cause of intellectual and developmental disability. Hypoxia causes neuronal dysfunction and death in the developing cerebral cortex due to excitotoxic Ca2+-influx. In the translational piglet model of hypoxic encephalopathy, we have previously shown that hypoxia overactivates Ca2+/Calmodulin (CaM) signaling via Sarcoma (Src) kinase in cortical neurons, resulting in overexpression of proapoptotic genes. However, identifying the exact relationship between alterations in neuronal Ca2+-influx, molecular determinants of cell death, and the degree of hypoxia in a dynamic system represents a significant challenge. METHODS We used experimental and computational methods to identify molecular events critical to the onset of excitotoxicity-induced apoptosis in the cerebral cortex of newborn piglets. We used 2-3-day-old piglets (normoxic [Nx], hypoxic [Hx], and hypoxic + Src-inhibitor-treatment [Hx+PP2] groups) for biochemical analysis of ATP production, Ca2+-influx, and Ca2+/CaM-dependent protein kinase kinase 2 (CaMKK2) expression. We then used SimBiology to build a computational model of the Ca2+/CaM-Src-kinase signaling cascade, simulating Nx, Hx, and Hx+PP2 conditions. To evaluate our model, we used Sobol variance decomposition, multiparametric global sensitivity analysis, and parameter scanning. RESULTS Our model captures important molecular trends caused by hypoxia in the piglet brain. Incorporating the action of Src kinase inhibitor PP2 further validated our model and enabled predictive analysis of the effect of hypoxia on CaMKK2. We determined the impact of a feedback loop related to Src phosphorylation of NMDA receptors and activation kinetics of CaMKII. We also identified distinct modes of signaling wherein Ca2+ level alterations following Src kinase inhibition may not be a linear predictor of changes in Bax expression. Importantly, our model indicates that while pharmacological pre-treatment significantly reduces the onset of abnormal Ca2+-influx, there exists a window of intervention after hypoxia during which targeted modulation of Src-NMDAR interaction kinetics in combination with PP2 administration can reduce Ca2+-influx and Bax expression to similar levels as pre-treatment. CONCLUSIONS Our model identifies new dynamics of critical components in the Ca2+/CaM-Src signaling pathway leading to neuronal injury and provides a feasible framework for drug efficacy studies in translational models of neonatal brain injury for the prevention of intellectual and developmental disabilities.
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Affiliation(s)
- Panagiotis Kratimenos
- Center for Neuroscience Research, Children's National Research Institute, Children's National Hospital, 111 Michigan Avenue, Washington, DC, 20010, USA. .,Department of Pediatrics, Division of Neonatology, Children's National Hospital, Washington DC, USA. .,George Washington University School of Medicine and Health Sciences, Washington DC, USA.
| | - Abhya Vij
- George Washington University School of Medicine and Health Sciences, Washington DC, USA
| | | | - Ioannis Koutroulis
- George Washington University School of Medicine and Health Sciences, Washington DC, USA.,Department of Pediatrics, Division of Emergency Medicine, Children's National Hospital, Washington, DC, USA.,Center for Genetic Medicine Research, Children's National Research Institute and Department of Genomics and Precision Medicine, George Washington University School of Medicine and Health Sciences, Washington, DC, USA
| | | | - Vittorio Gallo
- Center for Neuroscience Research, Children's National Research Institute, Children's National Hospital, 111 Michigan Avenue, Washington, DC, 20010, USA.,George Washington University School of Medicine and Health Sciences, Washington DC, USA
| | - Aaron Sathyanesan
- Center for Neuroscience Research, Children's National Research Institute, Children's National Hospital, 111 Michigan Avenue, Washington, DC, 20010, USA. .,George Washington University School of Medicine and Health Sciences, Washington DC, USA.
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Vacher CM, Lacaille H, O'Reilly JJ, Salzbank J, Bakalar D, Sebaoui S, Liere P, Clarkson-Paredes C, Sasaki T, Sathyanesan A, Kratimenos P, Ellegood J, Lerch JP, Imamura Y, Popratiloff A, Hashimoto-Torii K, Gallo V, Schumacher M, Penn AA. Placental endocrine function shapes cerebellar development and social behavior. Nat Neurosci 2021; 24:1392-1401. [PMID: 34400844 PMCID: PMC8481124 DOI: 10.1038/s41593-021-00896-4] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 06/23/2021] [Indexed: 02/07/2023]
Abstract
Compromised placental function or premature loss has been linked to diverse neurodevelopmental disorders. Here we show that placenta allopregnanolone (ALLO), a progesterone-derived GABA-A receptor (GABAAR) modulator, reduction alters neurodevelopment in a sex-linked manner. A new conditional mouse model, in which the gene encoding ALLO's synthetic enzyme (akr1c14) is specifically deleted in trophoblasts, directly demonstrated that placental ALLO insufficiency led to cerebellar white matter abnormalities that correlated with autistic-like behavior only in male offspring. A single injection of ALLO or muscimol, a GABAAR agonist, during late gestation abolished these alterations. Comparison of male and female human preterm infant cerebellum also showed sex-linked myelination marker alteration, suggesting similarities between mouse placental ALLO insufficiency and human preterm brain development. This study reveals a new role for a placental hormone in shaping brain regions and behaviors in a sex-linked manner. Placental hormone replacement might offer novel therapeutic opportunities to prevent later neurobehavioral disorders.
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Affiliation(s)
- Claire-Marie Vacher
- Department of Pediatrics, Columbia University, New York-Presbyterian Morgan Stanley Children's Hospital, New York, NY, USA.
| | - Helene Lacaille
- Department of Pediatrics, Columbia University, New York-Presbyterian Morgan Stanley Children's Hospital, New York, NY, USA
| | - Jiaqi J O'Reilly
- Department of Pediatrics, Columbia University, New York-Presbyterian Morgan Stanley Children's Hospital, New York, NY, USA
| | - Jacquelyn Salzbank
- Department of Pediatrics, Columbia University, New York-Presbyterian Morgan Stanley Children's Hospital, New York, NY, USA
| | - Dana Bakalar
- National Institutes of Health, Bethesda, MD, USA
| | - Sonia Sebaoui
- Center for Neuroscience Research, Children's National Health System, Washington, DC, USA
| | - Philippe Liere
- U1195 INSERM, Paris-Saclay University, Le Kremlin-Bicêtre Cedex, France
| | | | - Toru Sasaki
- Center for Neuroscience Research, Children's National Health System, Washington, DC, USA
| | - Aaron Sathyanesan
- Center for Neuroscience Research, Children's National Health System, Washington, DC, USA
| | - Panagiotis Kratimenos
- Center for Neuroscience Research, Children's National Health System, Washington, DC, USA
- The George Washington University School of Medicine and Health Sciences, Pediatrics, Washington, DC, USA
| | - Jacob Ellegood
- Mouse Imaging Centre (MICe), Hospital for Sick Children, Toronto, ON, Canada
| | - Jason P Lerch
- Mouse Imaging Centre (MICe), Hospital for Sick Children, Toronto, ON, Canada
- Wellcome Centre for Integrative Neuroimaging (WIN), Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Yuka Imamura
- Department of Biochemistry and Molecular Biology, Pennsylvania State University College of Medicine, Pittsburgh, PA, USA
| | - Anastas Popratiloff
- The George Washington University, Nanofabrication and Imaging Center, Washington, DC, USA
- The George Washington University, SMHS, Anatomy & Cell Biology, Washington, DC, USA
| | - Kazue Hashimoto-Torii
- Center for Neuroscience Research, Children's National Health System, Washington, DC, USA
- The George Washington University School of Medicine and Health Sciences, Pediatrics, Washington, DC, USA
| | - Vittorio Gallo
- Center for Neuroscience Research, Children's National Health System, Washington, DC, USA
- The George Washington University School of Medicine and Health Sciences, Pediatrics, Washington, DC, USA
| | | | - Anna A Penn
- Department of Pediatrics, Columbia University, New York-Presbyterian Morgan Stanley Children's Hospital, New York, NY, USA.
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Sathyanesan A, Zhou J, Scafidi J, Heck DH, Sillitoe RV, Gallo V. Emerging connections between cerebellar development, behaviour and complex brain disorders. Nat Rev Neurosci 2019; 20:298-313. [PMID: 30923348 DOI: 10.1038/s41583-019-0152-2] [Citation(s) in RCA: 144] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The human cerebellum has a protracted developmental timeline compared with the neocortex, expanding the window of vulnerability to neurological disorders. As the cerebellum is critical for motor behaviour, it is not surprising that most neurodevelopmental disorders share motor deficits as a common sequela. However, evidence gathered since the late 1980s suggests that the cerebellum is involved in motor and non-motor function, including cognition and emotion. More recently, evidence indicates that major neurodevelopmental disorders such as intellectual disability, autism spectrum disorder, attention-deficit hyperactivity disorder and Down syndrome have potential links to abnormal cerebellar development. Out of recent findings from clinical and preclinical studies, the concept of the 'cerebellar connectome' has emerged that can be used as a framework to link the role of cerebellar development to human behaviour, disease states and the design of better therapeutic strategies.
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Affiliation(s)
- Aaron Sathyanesan
- Center for Neuroscience Research, Children's Research Institute, Children's National Health System, Washington, DC, USA.
| | - Joy Zhou
- Department of Pathology and Immunology, Baylor College of Medicine, Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, Houston, TX, USA.,Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Joseph Scafidi
- Center for Neuroscience Research, Children's Research Institute, Children's National Health System, Washington, DC, USA.,George Washington University School of Medicine and Health Sciences, Washington, DC, USA
| | - Detlef H Heck
- Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Roy V Sillitoe
- Department of Pathology and Immunology, Baylor College of Medicine, Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, Houston, TX, USA.,Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA.,Program in Developmental Biology, Baylor College of Medicine, Houston, TX, USA
| | - Vittorio Gallo
- Center for Neuroscience Research, Children's Research Institute, Children's National Health System, Washington, DC, USA. .,George Washington University School of Medicine and Health Sciences, Washington, DC, USA.
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Sathyanesan A, Gallo V. Cerebellar contribution to locomotor behavior: A neurodevelopmental perspective. Neurobiol Learn Mem 2019; 165:106861. [PMID: 29723669 PMCID: PMC7303045 DOI: 10.1016/j.nlm.2018.04.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 04/06/2018] [Accepted: 04/24/2018] [Indexed: 12/30/2022]
Abstract
The developmental trajectory of the formation of cerebellar circuitry has significant implications for locomotor plasticity and adaptive learning at later stages. While there is a wealth of knowledge on the development of locomotor behavior in human infants, children, and adolescents, pre-clinical animal models have fallen behind on the study of the emergence of behavioral motifs in locomotor function across postnatal development. Since cerebellar development is protracted, it is subject to higher risk of genetic or environmental disruption, potentially leading to abnormal behavioral development. This highlights the need for more sophisticated and specific functional analyses of adaptive cerebellar behavior within the context of whole-body locomotion across the entire span of postnatal development. Here we review evidence on cerebellar contribution to adaptive locomotor behavior, highlighting methodologies employed to quantify and categorize behavior at different developmental stages, with the ultimate goal of following the course of early behavioral alterations in neurodevelopmental disorders. Since experimental paradigms used to study cerebellar behavior are lacking in both specificity and applicability to locomotor contexts, we highlight the use of the Erasmus Ladder - an advanced, computerized, fully automated system to quantify adaptive cerebellar learning in conjunction with locomotor function. Finally, we emphasize the need to develop objective, quantitative, behavioral tasks which can track changes in developmental trajectories rather than endpoint measurement at the adult stage of behavior.
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Affiliation(s)
- Aaron Sathyanesan
- Center for Neuroscience Research, Children's Research Institute, Children's National Health System, Washington, DC, USA.
| | - Vittorio Gallo
- Center for Neuroscience Research, Children's Research Institute, Children's National Health System, Washington, DC, USA; George Washington University School of Medicine and Health Sciences, USA
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Szebenyi SA, Ogura T, Sathyanesan A, AlMatrouk AK, Chang J, Lin W. Increases in intracellular calcium via activation of potentially multiple phospholipase C isozymes in mouse olfactory neurons. Front Cell Neurosci 2014; 8:336. [PMID: 25374507 PMCID: PMC4204526 DOI: 10.3389/fncel.2014.00336] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Accepted: 10/01/2014] [Indexed: 11/13/2022] Open
Abstract
Phospholipase C (PLC) and internal Ca(2+) stores are involved in a variety of cellular functions. However, our understanding of PLC in mammalian olfactory sensory neurons (OSNs) is generally limited to its controversial role in odor transduction. Here we employed single-cell Ca(2+) imaging and molecular approaches to investigate PLC-mediated Ca(2+) responses and its isozyme gene transcript expression. We found that the pan-PLC activator m-3M3FBS (25 μM) induces intracellular Ca(2+) increases in vast majority of isolated mouse OSNs tested. Both the response amplitude and percent responding cells depend on m-3M3FBS concentrations. In contrast, the inactive analog o-3M3FBS fails to induce Ca(2+) responses. The m-3M3FBS-induced Ca(2+) increase is blocked by the PLC inhibitor U73122, while its inactive analog U73433 has no effect. Removal of extracellular Ca(2+) does not change significantly the m-3M3FBS-induced Ca(2+) response amplitude. Additionally, in the absence of external Ca(2+), we found that a subset of OSNs respond to an odorant mixture with small Ca(2+) increases, which are significantly suppressed by U73122. Furthermore, using reverse transcription polymerase chain reaction and real-time quantitative polymerase chain reaction, we found that multiple PLC isozyme gene transcripts are expressed in olfactory turbinate tissue in various levels. Using RNA in situ hybridization analysis, we further show expression of β4, γ1, γ2 gene transcripts in OSNs. Taken together, our results establish that PLC isozymes are potent enzymes for mobilizing intracellular Ca(2+) in mouse OSNs and provide molecular insight for PLC isozymes-mediated complex cell signaling and regulation in the peripheral olfactory epithelium.
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Affiliation(s)
- Steven A Szebenyi
- Department of Biological Sciences, University of Maryland Baltimore County Baltimore, MD, USA
| | - Tatsuya Ogura
- Department of Biological Sciences, University of Maryland Baltimore County Baltimore, MD, USA
| | - Aaron Sathyanesan
- Department of Biological Sciences, University of Maryland Baltimore County Baltimore, MD, USA
| | - Abdullah K AlMatrouk
- Department of Biological Sciences, University of Maryland Baltimore County Baltimore, MD, USA
| | - Justin Chang
- Department of Biological Sciences, University of Maryland Baltimore County Baltimore, MD, USA
| | - Weihong Lin
- Department of Biological Sciences, University of Maryland Baltimore County Baltimore, MD, USA
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Sathyanesan A, Feijoo AA, Mehta ST, Nimarko AF, Lin W. Expression profile of G-protein βγ subunit gene transcripts in the mouse olfactory sensory epithelia. Front Cell Neurosci 2013; 7:84. [PMID: 23759900 PMCID: PMC3671183 DOI: 10.3389/fncel.2013.00084] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Accepted: 05/16/2013] [Indexed: 11/24/2022] Open
Abstract
Heterotrimeric G-proteins mediate a variety of cellular functions, including signal transduction in sensory neurons of the olfactory system. Whereas the Gα subunits in these neurons are well characterized, the gene transcript expression profile of Gβγ subunits is largely missing. Here we report our comprehensive expression analysis to identify Gβ and Gγ subunit gene transcripts in the mouse main olfactory epithelium (MOE) and the vomeronasal organ (VNO). Our reverse transcriptase PCR (RT-PCR) and realtime qPCR analyses of all known Gβ (β1,2,3,4,5) and Gγ (γ1,2,2t,3,4,5,7,8,10,11,12,13) subunits indicate presence of multiple Gβ and Gγ subunit gene transcripts in the MOE and the VNO at various expression levels. These results are supported by our RNA in situ hybridization (RISH) experiments, which reveal the expression patterns of two Gβ subunits and four Gγ subunits in the MOE as well as one Gβ and four Gγ subunits in the VNO. Using double-probe fluorescence RISH and line intensity scan analysis of the RISH signals of two dominant Gβγ subunits, we show that Gγ13 is expressed in mature olfactory sensory neurons (OSNs), while Gβ1 is present in both mature and immature OSNs. Interestingly, we also found Gβ1 to be the dominant Gβ subunit in the VNO and present throughout the sensory epithelium. In contrast, we found diverse expression of Gγ subunit gene transcripts with Gγ2, Gγ3, and Gγ13 in the Gαi2-expressing neuronal population, while Gγ8 is expressed in both layers. Further, we determined the expression of these Gβγ gene transcripts in three post-natal developmental stages (p0, 7, and 14) and found their cell-type specific expression remains largely unchanged, except the transient expression of Gγ2 in a single basal layer of cells in the MOE during P7 and P14. Taken together, our comprehensive expression analyses reveal cell-type specific gene expression of multiple Gβ and Gγ in sensory neurons of the olfactory system.
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Affiliation(s)
- Aaron Sathyanesan
- Department of Biological Sciences, University of Maryland Baltimore County, Baltimore MD, USA
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Krosnowski K, Ashby S, Sathyanesan A, Luo W, Ogura T, Lin W. Diverse populations of intrinsic cholinergic interneurons in the mouse olfactory bulb. Neuroscience 2012; 213:161-78. [PMID: 22525133 DOI: 10.1016/j.neuroscience.2012.04.024] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2011] [Revised: 04/10/2012] [Accepted: 04/12/2012] [Indexed: 10/28/2022]
Abstract
Cholinergic activities affect olfactory bulb (OB) information processing and associated learning and memory. However, the presence of intrinsic cholinergic interneurons in the OB remains controversial. As a result, morphological and functional properties of these cells are largely undetermined. We characterized cholinergic interneurons using transgenic mice that selectively mark choline acetyltransferase (ChAT)-expressing cells and immunolabeling. We found a significant number of intrinsic cholinergic interneurons in the OB. These interneurons reside primarily in the glomerular layer (GL) and external plexiform layer (EPL) and exhibit diverse distribution patterns of nerve processes, indicating functional heterogeneity. Further, we found these neurons express ChAT and vesicular acetylcholine transporter (VAChT), but do not immunoreact to glutamatergic, GABAergic or dopaminergic markers and are distinct from calretinin-expressing interneurons. Interestingly, the cholinergic population partially overlaps with the calbindin D28K-expressing interneuron population, revealing the neurotransmitter identity of this sub-population. Additionally, we quantitatively determined the density of VAChT labeled cholinergic nerve fibers in various layers of the OB, as well as the intensity of VAChT immunoreactivity within the GL, suggesting primary sites of cholinergic actions. Taken together, our results provide clear evidence showing the presence of a significant number of cholinergic interneurons and that these morphologically and distributionally diverse interneurons make up complex local cholinergic networks in the OB. Thus, our results suggest that olfactory information processing is modulated by dual cholinergic systems of local interneuron networks and centrifugal projections.
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Affiliation(s)
- K Krosnowski
- Department of Biological Sciences, University of Maryland, Baltimore County, Baltimore, MD 21250, USA
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Sathyanesan A, Ogura T, Lin W. Automated measurement of nerve fiber density using line intensity scan analysis. J Neurosci Methods 2012; 206:165-75. [PMID: 22613744 DOI: 10.1016/j.jneumeth.2012.02.019] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2011] [Revised: 02/16/2012] [Accepted: 02/20/2012] [Indexed: 11/27/2022]
Abstract
Quantification of nerve fibers in peripheral and central nervous systems is important for the understanding of neuronal function, organization and pathological changes. However, current methods to quantify nerve fibers are resource-intensive and often provide an indirect measurement of nerve fiber density. Here, we describe an automated and efficient method for nerve fiber quantification, which we developed by making use of widely available software and analytical techniques, including Hessian-based feature extraction in NIH ImageJ and line intensity scan analysis. The combined use of these analytical tools through an automated routine enables reliable detection and quantification of nerve fibers from low magnification, non-uniformly labeled epifluorescence images. This allows for time-efficient determination of nerve density and also comparative analysis in large brain structures, such as hippocampus or between various regions of neural circuitry. Using this method, we have obtained accurate measurements of cholinergic fiber density in hippocampus and a large area of cortex in mouse brain sections immunolabeled with an antibody against the vesicular acetylcholine transporter (VAChT). The density values are comparable among animals tested, showing a high degree of reproducibility. Because our method can be performed at relatively low cost and in large tissue sections where nerve fibers can be labeled by various antibodies or visualized by expression of reporter proteins, such as green fluorescent protein in transgenic mice, we expect our method to be broadly useful in both research and clinical investigation. To our knowledge, this is the first method to reliably quantify nerve fibers through a rapid and automated protocol.
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Affiliation(s)
- Aaron Sathyanesan
- Department of Biological Sciences, University of Maryland, Baltimore County, Baltimore, MD 21250, USA
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Ogura T, Szebenyi SA, Krosnowski K, Sathyanesan A, Jackson J, Lin W. Cholinergic microvillous cells in the mouse main olfactory epithelium and effect of acetylcholine on olfactory sensory neurons and supporting cells. J Neurophysiol 2011; 106:1274-87. [PMID: 21676931 DOI: 10.1152/jn.00186.2011] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The mammalian olfactory epithelium is made up of ciliated olfactory sensory neurons (OSNs), supporting cells, basal cells, and microvillous cells. Previously, we reported that a population of nonneuronal microvillous cells expresses transient receptor potential channel M5 (TRPM5). Using transgenic mice and immunocytochemical labeling, we identify that these cells are cholinergic, expressing the signature markers of choline acetyltransferase (ChAT) and the vesicular acetylcholine transporter. This result suggests that acetylcholine (ACh) can be synthesized and released locally to modulate activities of neighboring supporting cells and OSNs. In Ca(2+) imaging experiments, ACh induced increases in intracellular Ca(2+) levels in 78% of isolated supporting cells tested in a concentration-dependent manner. Atropine, a muscarinic ACh receptor (mAChR) antagonist suppressed the ACh responses. In contrast, ACh did not induce or potentiate Ca(2+) increases in OSNs. Instead ACh suppressed the Ca(2+) increases induced by the adenylyl cyclase activator forskolin in some OSNs. Supporting these results, we found differential expression of mAChR subtypes in supporting cells and OSNs using subtype-specific antibodies against M(1) through M(5) mAChRs. Furthermore, we found that various chemicals, bacterial lysate, and cold saline induced Ca(2+) increases in TRPM5/ChAT-expressing microvillous cells. Taken together, our data suggest that TRPM5/ChAT-expressing microvillous cells react to certain chemical or thermal stimuli and release ACh to modulate activities of neighboring supporting cells and OSNs via mAChRs. Our studies reveal an intrinsic and potentially potent mechanism linking external stimulation to cholinergic modulation of activities in the olfactory epithelium.
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Affiliation(s)
- Tatsuya Ogura
- Department of Biological Sciences, University of Maryland, Baltimore County, Baltimore, MD 21250, USA
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