1
|
Ascoli GA. Cell morphologies in the nervous system: Glia steal the limelight. J Comp Neurol 2023; 531:338-343. [PMID: 36316800 PMCID: PMC9772107 DOI: 10.1002/cne.25429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 10/12/2022] [Accepted: 10/13/2022] [Indexed: 12/24/2022]
Abstract
Neurons and glia have distinct yet interactive functions but are both characterized by branching morphology. Dendritic trees have been digitally traced for over 40 years in many animal species, anatomical regions, and neuron types. Recently, long-range axons also are being reconstructed throughout the brain of many organisms from invertebrates to primates. In contrast, less attention has been paid until lately to glial morphology. Thus, although glia and neurons are similarly abundant in the nervous systems of humans and most animal models, glia have traditionally been much less represented than neurons in morphological reconstruction repositories such as NeuroMorpho.Org. This is rapidly changing with the advent of high-throughput glia tracing. NeuroMorpho.Org introduced glial cells in 2017 and today they constitute nearly a third of the database content. It took NeuroMorpho.Org 10 years to collect the first 40,000 neurons and now that amount of data can be produced in a single publication. This not only demonstrates the spectacular technological progress in data production, but also demands a corresponding advancement in informatics processing. At the same time, these publicly available data also open new opportunities for quantitative analysis and computational modeling to identify universal or cell-type-specific design principles in the cellular architecture of nervous systems. As a first application, we demonstrated that supervised machine learning of tree geometry classifies neurons and glia with practically perfect accuracy. Furthermore, we discovered a new morphometric biomarker capable of robustly separating these cell classes across multiple species, brain regions, and experimental preparations, with only sparse sampling of branch measurements.
Collapse
Affiliation(s)
- Giorgio A. Ascoli
- Center for Neural Informatics, Structures, & Plasticity (CN3), Bioengineering Department, and Neuroscience ProgramGeorge Mason UniversityFairfaxVirginiaUSA
| |
Collapse
|
2
|
Zhuang H, Yao X, Li H, Li Q, Yang C, Wang C, Xu D, Xiao Y, Gao Y, Gao J, Bi M, Liu R, Teng G, Liu L. Long-term high-fat diet consumption by mice throughout adulthood induces neurobehavioral alterations and hippocampal neuronal remodeling accompanied by augmented microglial lipid accumulation. Brain Behav Immun 2022; 100:155-171. [PMID: 34848340 DOI: 10.1016/j.bbi.2021.11.018] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 11/22/2021] [Accepted: 11/23/2021] [Indexed: 01/01/2023] Open
Abstract
High-fat diet (HFD) consumption is generally associated with an increased risk of cognitive and emotional dysfunctions that constitute a sizeable worldwide health burden with profound social and economic consequences. Middle age is a critical time period that affects one's health later in life; pertinently, the prevalence of HFD consumption is increasing among mature adults. Given the growing health-related economic burden imposed globally by increasing rates of noncommunicable diseases in rapidly aging populations, along with the pervasive but insidious health impairments associated with HFD consumption, it is critically important to understand the effects of long-term HFD consumption on brain function and to gain insights into their potential underlying mechanisms. In the present study, adult male C57BL/6J mice were randomly assigned a control diet (CD, 10 kJ% from fat) or an HFD (60 kJ% from fat) for 6 months (6 M) or 9 months (9 M) followed by behavioral tests, serum biochemical analysis, and histological examinations of both the dorsal and ventral regions of the hippocampus. In both the 6 M and 9 M cohorts, mice that consumed an HFD exhibited poorer memory performance in the Morris water maze test (MWM) and greater depression- and anxiety-like behavior during the open field test (OFT), sucrose preference test (SPT) and forced swim test (FST) than control mice. Compared with age-matched mice in the CD group, mice in the HFD group showed abnormal hippocampal neuronal morphology, which was particularly evident in the ventral hippocampus. Hippocampal microglia in mice in the HFD group generally had a more activated phenotype evidenced by a smaller microglial territory area and increased cluster of differentiation 68 (CD68, a marker of phagocytic activity) immunoreactivity, while the microglial density in the dentate gyrus (DG) was decreased, indicating microglial decline. The engulfment of postsynaptic density 95 (PSD95, a general postsynaptic marker) puncta by microglia was increased in the HFD groups. Histological analysis of neutral lipids using a fluorescent probe (BODIPY) revealed that the total neutral lipid content in regions of interests (ROIs) and the lipid load in microglia were increased in the HFD group relative to the age-matched CD group. In summary, our results demonstrated that chronic HFD consumption from young adulthood to middle age induced anxiety- and depression-like behavior as well as memory impairment. The negative influence of chronic HFD consumption on behavioral and hippocampal neuroplasticity appears to be linked to a change in microglial phenotype that is accompanied by a remarkable increase in cellular lipid accumulation. These observations highlighting the potential to target lipid metabolism deficits to reduce the risk of HFD-associated emotional dysfunctions.
Collapse
Affiliation(s)
- Hong Zhuang
- Department of Physiology, Medical College, Southeast University, Nanjing 210009, China
| | - Xiuting Yao
- Department of Physiology, Medical College, Southeast University, Nanjing 210009, China
| | - Hong Li
- School of Life Science and Technology, Southeast University, Nanjing 210096, China
| | - Qian Li
- School of Life Science and Technology, Southeast University, Nanjing 210096, China
| | - Chenxi Yang
- Department of Physiology, Medical College, Southeast University, Nanjing 210009, China
| | - Conghui Wang
- Department of Physiology, Medical College, Southeast University, Nanjing 210009, China
| | - Dan Xu
- School of Public Health, Southeast University, Nanjing 210009
| | - Yu Xiao
- Department of Physiology, Medical College, Southeast University, Nanjing 210009, China
| | - Yuan Gao
- Medical College, Southeast University, Nanjing 210009, China
| | - Jiayi Gao
- Medical College, Southeast University, Nanjing 210009, China
| | - Mingze Bi
- Medical College, Southeast University, Nanjing 210009, China
| | - Rui Liu
- Medical College, Southeast University, Nanjing 210009, China
| | - Gaojun Teng
- Jiangsu Key Laboratory of Molecular Imaging and Functional Imaging, Department of Radiology, Zhongda Hospital, Medical School, Southeast University, Nanjing 210009, China.
| | - Lijie Liu
- Department of Physiology, Medical College, Southeast University, Nanjing 210009, China.
| |
Collapse
|
3
|
Poppe L, Rué L, Timmers M, Lenaerts A, Storm A, Callaerts-Vegh Z, Courtand G, de Boer A, Smolders S, Van Damme P, Van Den Bosch L, D'Hooge R, De Strooper B, Robberecht W, Lemmens R. EphA4 loss improves social memory performance and alters dendritic spine morphology without changes in amyloid pathology in a mouse model of Alzheimer's disease. ALZHEIMERS RESEARCH & THERAPY 2019; 11:102. [PMID: 31831046 PMCID: PMC6909519 DOI: 10.1186/s13195-019-0554-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Accepted: 11/08/2019] [Indexed: 12/24/2022]
Abstract
Background EphA4 is a receptor of the ephrin system regulating spine morphology and plasticity in the brain. These processes are pivotal in the pathophysiology of Alzheimer’s disease (AD), characterized by synapse dysfunction and loss, and the progressive loss of memory and other cognitive functions. Reduced EphA4 signaling has been shown to rescue beta-amyloid-induced dendritic spine loss and long-term potentiation (LTP) deficits in cultured hippocampal slices and primary hippocampal cultures. In this study, we investigated whether EphA4 ablation might preserve synapse function and ameliorate cognitive performance in the APPPS1 transgenic mouse model of AD. Methods A postnatal genetic ablation of EphA4 in the forebrain was established in the APPPS1 mouse model of AD, followed by a battery of cognitive tests at 9 months of age to investigate cognitive function upon EphA4 loss. A Golgi-Cox staining was used to explore alterations in dendritic spine density and morphology in the CA1 region of the hippocampus. Results Upon EphA4 loss in APPPS1 mice, we observed improved social memory in the preference for social novelty test without affecting other cognitive functions. Dendritic spine analysis revealed altered synapse morphology as characterized by increased dendritic spine length and head width. These modifications were independent of hippocampal plaque load and beta-amyloid peptide levels since these were similar in mice with normal versus reduced levels of EphA4. Conclusion Loss of EphA4 improved social memory in a mouse model of Alzheimer’s disease in association with alterations in spine morphology.
Collapse
Affiliation(s)
- Lindsay Poppe
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute (LBI), KU Leuven - University of Leuven, Leuven, Belgium.,Laboratory of Neurobiology, Center for Brain and Disease Research, VIB, Leuven, Belgium
| | - Laura Rué
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute (LBI), KU Leuven - University of Leuven, Leuven, Belgium.,Laboratory of Neurobiology, Center for Brain and Disease Research, VIB, Leuven, Belgium
| | - Mieke Timmers
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute (LBI), KU Leuven - University of Leuven, Leuven, Belgium.,Laboratory of Neurobiology, Center for Brain and Disease Research, VIB, Leuven, Belgium
| | - Annette Lenaerts
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute (LBI), KU Leuven - University of Leuven, Leuven, Belgium.,Laboratory of Neurobiology, Center for Brain and Disease Research, VIB, Leuven, Belgium
| | - Annet Storm
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute (LBI), KU Leuven - University of Leuven, Leuven, Belgium.,Laboratory of Neurobiology, Center for Brain and Disease Research, VIB, Leuven, Belgium
| | - Zsuzsanna Callaerts-Vegh
- Laboratory of Biological Psychology, Faculty of Psychology and Educational Sciences, KU Leuven - University of Leuven, Leuven, Belgium.,mINT Animal Behavior Core Facility, Faculty of Psychology, KU Leuven, Leuven, Belgium
| | - Gilles Courtand
- Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, Unité Mixte de Recherche 5287, Centre National de la Recherche Scientifique, Université de Bordeaux, 33076, Bordeaux, France
| | - Antina de Boer
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute (LBI), KU Leuven - University of Leuven, Leuven, Belgium.,Laboratory of Neurobiology, Center for Brain and Disease Research, VIB, Leuven, Belgium
| | - Silke Smolders
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute (LBI), KU Leuven - University of Leuven, Leuven, Belgium.,Laboratory of Neurobiology, Center for Brain and Disease Research, VIB, Leuven, Belgium
| | - Philip Van Damme
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute (LBI), KU Leuven - University of Leuven, Leuven, Belgium.,Laboratory of Neurobiology, Center for Brain and Disease Research, VIB, Leuven, Belgium.,Department of Neurology, University Hospitals Leuven, Herestraat 49, B-3000, Leuven, Belgium
| | - Ludo Van Den Bosch
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute (LBI), KU Leuven - University of Leuven, Leuven, Belgium.,Laboratory of Neurobiology, Center for Brain and Disease Research, VIB, Leuven, Belgium
| | - Rudi D'Hooge
- Laboratory of Biological Psychology, Faculty of Psychology and Educational Sciences, KU Leuven - University of Leuven, Leuven, Belgium
| | - Bart De Strooper
- VIB Center for Brain and Disease Research, Leuven, Belgium.,Department of Neurosciences, Katholieke Universiteit Leuven, Leuven, Belgium.,UK Dementia Research Institute at University College London, London, UK
| | - Wim Robberecht
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute (LBI), KU Leuven - University of Leuven, Leuven, Belgium.,Department of Neurology, University Hospitals Leuven, Herestraat 49, B-3000, Leuven, Belgium
| | - Robin Lemmens
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute (LBI), KU Leuven - University of Leuven, Leuven, Belgium. .,Laboratory of Neurobiology, Center for Brain and Disease Research, VIB, Leuven, Belgium. .,Department of Neurology, University Hospitals Leuven, Herestraat 49, B-3000, Leuven, Belgium.
| |
Collapse
|
6
|
Puschban Z, Sah A, Grutsch I, Singewald N, Dechant G. Reduced Anxiety-Like Behavior and Altered Hippocampal Morphology in Female p75NTR(exon IV-/-) Mice. Front Behav Neurosci 2016; 10:103. [PMID: 27313517 PMCID: PMC4887477 DOI: 10.3389/fnbeh.2016.00103] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Accepted: 05/13/2016] [Indexed: 02/05/2023] Open
Abstract
The presence of the p75 neurotrophin receptor (p75NTR) in adult basal forebrain cholinergic neurons, precursor cells in the subventricular cell layer and the subgranular cell layer of the hippocampus has been linked to alterations in learning as well as anxiety- and depression- related behaviors. In contrast to previous studies performed in a p75NTRexon III−/− model still expressing the short isoform of the p75NTR, we focused on locomotor and anxiety–associated behavior in p75NTRexon IV−/− mice lacking both p75NTR isoforms. Comparing p75NTRexon IV−/− and wildtype mice for both male and female animals showed an anxiolytic-like behavior as evidenced by increased central activities in the open field paradigm and flex field activity system as well as higher numbers of open arm entries in the elevated plus maze test in female p75NTR knockout mice. Morphometrical analyses of dorsal and ventral hippocampus revealed a reduction of width of the dentate gyrus and the granular cell layer in the dorsal but not ventral hippocampus in male and female p75NTRexon IV−/− mice. We conclude that germ-line deletion of p75NTR seems to differentially affect morphometry of dorsal and ventral dentate gyrus and that p75NTR may play a role in anxiety-like behavior, specifically in female mice.
Collapse
Affiliation(s)
- Zoe Puschban
- Department of Neuroscience, Innsbruck Medical University Innsbruck, Austria
| | - Anupam Sah
- Department of Pharmacology and Toxicology, Institute of Pharmacy, Center for Molecular Biosciences (CMBI), Leopold-Franzens University of Innsbruck Innsbruck, Austria
| | - Isabella Grutsch
- Department of Neuroscience, Innsbruck Medical University Innsbruck, Austria
| | - Nicolas Singewald
- Department of Pharmacology and Toxicology, Institute of Pharmacy, Center for Molecular Biosciences (CMBI), Leopold-Franzens University of Innsbruck Innsbruck, Austria
| | - Georg Dechant
- Department of Neuroscience, Innsbruck Medical University Innsbruck, Austria
| |
Collapse
|
7
|
Fujiwara K, Fujita Y, Kasai A, Onaka Y, Hashimoto H, Okada H, Yamashita T. Deletion of JMJD2B in neurons leads to defective spine maturation, hyperactive behavior and memory deficits in mouse. Transl Psychiatry 2016; 6:e766. [PMID: 27023172 PMCID: PMC4872455 DOI: 10.1038/tp.2016.31] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Revised: 01/21/2016] [Accepted: 01/24/2016] [Indexed: 12/12/2022] Open
Abstract
JMJD2B is a histone demethylase enzyme that regulates gene expression through demethylation of H3K9me3. Although mutations of JMJD2B have been suggested to be responsible for neurodevelopmental disorders, the function of JMJD2B in the central nervous system (CNS) remains to be elucidated. Here we show that JMJD2B has a critical role in the development of the CNS. We observed JMJD2B expression, which was especially strong in the hippocampus, throughout the CNS from embryonic periods through adulthood. We generated neuron-specific JMJD2B-deficient mice using the cre-loxP system. We found an increase in total spine number, but a decrease in mature spines, in the CA1 region of the hippocampus. JMJD2B-deficient mice exhibited hyperactive behavior, sustained hyperactivity in a novel environment, deficits in working memory and spontaneous epileptic-like seizures. Together these observations indicate that JMJD2B mutant mice display symptoms reminiscent of neurodevelopmental disorders. Our findings provide evidence for the involvement of histone demethylation in the formation of functional neural networks during development.
Collapse
Affiliation(s)
- K Fujiwara
- Department of Molecular Neuroscience, Graduate School of Medicine, Osaka University, Suita, Japan
- Japan Science and Technology Agency, CREST, Tokyo, Japan
| | - Y Fujita
- Department of Molecular Neuroscience, Graduate School of Medicine, Osaka University, Suita, Japan
- Japan Science and Technology Agency, CREST, Tokyo, Japan
| | - A Kasai
- Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Japan
| | - Y Onaka
- Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Japan
| | - H Hashimoto
- Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Japan
- iPS Cell-based Research Project on Brain Neuropharmacology and Toxicology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Japan
- Molecular Research Center for Children's Mental Development, United Graduate School of Child Development, Osaka University, Suita, Japan
| | - H Okada
- Department of Biochemistry, Kinki University Faculty of Medicine, Sayama, Japan
| | - T Yamashita
- Department of Molecular Neuroscience, Graduate School of Medicine, Osaka University, Suita, Japan
- Japan Science and Technology Agency, CREST, Tokyo, Japan
- , Department of Molecular Neuroscience, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita 565-0871, Japan. E-mail:
| |
Collapse
|