1
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Saxon D, Alderman PJ, Sorrells SF, Vicini S, Corbin JG. Neuronal Subtypes and Connectivity of the Adult Mouse Paralaminar Amygdala. eNeuro 2024; 11:ENEURO.0119-24.2024. [PMID: 38811163 PMCID: PMC11208988 DOI: 10.1523/eneuro.0119-24.2024] [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: 03/20/2024] [Revised: 05/03/2024] [Accepted: 05/10/2024] [Indexed: 05/31/2024] Open
Abstract
The paralaminar nucleus of the amygdala (PL) comprises neurons that exhibit delayed maturation. PL neurons are born during gestation but mature during adolescent ages, differentiating into excitatory neurons. These late-maturing PL neurons contribute to the increase in size and cell number of the amygdala between birth and adulthood. However, the function of the PL upon maturation is unknown, as the region has only recently begun to be characterized in detail. In this study, we investigated key defining features of the adult mouse PL; the intrinsic morpho-electric properties of its neurons, and its input and output circuit connectivity. We identify two subtypes of excitatory neurons in the PL based on unsupervised clustering of electrophysiological properties. These subtypes are defined by differential action potential firing properties and dendritic architecture, suggesting divergent functional roles. We further uncover major axonal inputs to the adult PL from the main olfactory network and basolateral amygdala. We also find that axonal outputs from the PL project reciprocally to these inputs and to diverse targets including the amygdala, frontal cortex, hippocampus, hypothalamus, and brainstem. Thus, the adult mouse PL is centrally placed to play a major role in the integration of olfactory sensory information, to coordinate affective and autonomic behavioral responses to salient odor stimuli.
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Affiliation(s)
- David Saxon
- Center for Neuroscience Research, Children's Research Institute, Children's National Hospital, Washington, DC 20011
- Interdisciplinary Program in Neuroscience, Georgetown University Medical Center, Washington, DC 20007
| | - Pia J Alderman
- Department of Neuroscience, University of Pittsburgh, Pittsburgh, Pennsylvania 15260
| | - Shawn F Sorrells
- Department of Neuroscience, University of Pittsburgh, Pittsburgh, Pennsylvania 15260
- Center for the Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, Pennsylvania 15260
| | - Stefano Vicini
- Interdisciplinary Program in Neuroscience, Georgetown University Medical Center, Washington, DC 20007
- Department of Pharmacology and Physiology, Georgetown University Medical Center, Washington, DC 20007
| | - Joshua G Corbin
- Center for Neuroscience Research, Children's Research Institute, Children's National Hospital, Washington, DC 20011
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2
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Perez GA, Park KW, Lanza D, Cicardo J, Danish Uddin M, Jankowsky JL. Generation of a Dcx-CreER T2 knock-in mouse for genetic manipulation of newborn neurons. Genesis 2024; 62:e23584. [PMID: 38102875 PMCID: PMC11021165 DOI: 10.1002/dvg.23584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 11/19/2023] [Accepted: 11/29/2023] [Indexed: 12/17/2023]
Abstract
A wide variety of CreERT2 driver lines are available for genetic manipulation of adult-born neurons in the mouse brain. These tools have been instrumental in studying fate potential, migration, circuit integration, and morphology of the stem cells supporting lifelong neurogenesis. Despite a wealth of tools, genetic manipulation of adult-born neurons for circuit and behavioral studies has been limited by poor specificity of many driver lines targeting early progenitor cells and by the inaccessibility of lines selective for later stages of neuronal maturation. We sought to address these limitations by creating a new CreERT2 driver line targeted to the endogenous mouse doublecortin locus as a marker of fate-specified neuroblasts and immature neurons. Our new model places a T2A-CreERT2 cassette immediately downstream of the Dcx coding sequence on the X chromosome, allowing expression of both Dcx and CreERT2 proteins in the endogenous spatiotemporal pattern for this gene. We demonstrate that the new mouse line drives expression of a Cre-dependent reporter throughout the brain in neonatal mice and in known neurogenic niches of adult animals. The line has been deposited with the Jackson Laboratory and should provide an accessible tool for studies targeting fate-restricted neuronal precursors.
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Affiliation(s)
- Gabriella A. Perez
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030
| | - Kyung-Won Park
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030
| | - Denise Lanza
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030
| | - Jenna Cicardo
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030
| | - M. Danish Uddin
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030
| | - Joanna L. Jankowsky
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030
- Departments of Neurology, Neurosurgery, and Molecular and Cellular Biology, Huffington Center on Aging, Baylor College of Medicine, Houston, TX 77030
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3
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Bonfanti L, Couillard-Després S. Neuron and Brain Maturation 2.0. Int J Mol Sci 2023; 24:17113. [PMID: 38069434 PMCID: PMC10707153 DOI: 10.3390/ijms242317113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Accepted: 11/23/2023] [Indexed: 12/18/2023] Open
Abstract
The mammalian central nervous system (CNS) is built up during embryogenesis by neural stem cells located in the periventricular germinal layers which undergo multiple division cycles [...].
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Affiliation(s)
- Luca Bonfanti
- Neuroscience Institute Cavalieri Ottolenghi (NICO), 10043 Orbassano, Italy
- Department of Veterinary Sciences, University of Turin, 10095 Torino, Italy
| | - Sébastien Couillard-Després
- Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), Paracelsus Medical University, 5020 Salzburg, Austria
- Institute of Experimental Neuroregeneration, Paracelsus Medical University, 5020 Salzburg, Austria
- Austrian Cluster for Tissue Regeneration, 1200 Vienna, Austria
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4
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Alshebib Y, Hori T, Goel A, Fauzi AA, Kashiwagi T. Adult human neurogenesis: A view from two schools of thought. IBRO Neurosci Rep 2023; 15:342-347. [PMID: 38025659 PMCID: PMC10665662 DOI: 10.1016/j.ibneur.2023.07.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 07/21/2023] [Accepted: 07/27/2023] [Indexed: 12/01/2023] Open
Abstract
Are we truly losing neurons as we grow older? If yes, why, and how can the lost neurons be replaced or compensated for? Is so-called adult neurogenesis (ANG) still a controversial process, particularly in the human cerebral cortex? How do adult-born neurons -if proven to exist- contribute to brain functions? Is adult neurogenesis a disease-relevant process, meaning that neural progenitor cells are dormant in adulthood, but they may be reactivated, for example, following stroke? Is the earnest hope to cure neurological diseases justifying the readiness to accept ANG claim uncritically? These are all fundamental issues that have not yet been firmly explained. Although it is completely understandable that some researchers believe that we can add new neurons to our inevitably deteriorating brain, the brain regeneration process still possesses intellectually and experimentally diverting views, as until now, there has been significant confusion about the concept of ANG. This paper is not intended to be an extensively analytical review distilling all findings and conclusions presented in the ANG literature. Instead, it is an attempt to discuss the commonly entertained opinions and then present our reflective insight concerning the current status quo of the field, which might help redirect research questions, avoid marketing an exaggerated hope, and more importantly, save the ever-limited resources, namely, intellectuals' time, facilities, and grants.
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Affiliation(s)
- Yasir Alshebib
- Department of Histology and Neuroanatomy, Tokyo Medical University, Tokyo 160-8402, Japan
- Department of Neurosurgery, Tokyo Neurological Center Hospital, Tokyo 134–0088, Japan
| | - Tomokatsu Hori
- Department of Neurosurgery, Tokyo Neurological Center Hospital, Tokyo 134–0088, Japan
| | - Atul Goel
- Department of Neurosurgery. K.E.M. Hospital and Seth G.S. Medical College, Parel, Mumbai 400 012, Maharashtra, India
| | - Asra Al Fauzi
- Department of Neurosurgery, Faculty of Medicine Universitas Airlangga, Dr. Soetomo General Academic Hospital, Jl. Prof. Dr. Moestopo 6–8, Surabaya, Indonesia
| | - Taichi Kashiwagi
- Department of Histology and Neuroanatomy, Tokyo Medical University, Tokyo 160-8402, Japan
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5
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Bonfanti L, La Rosa C, Ghibaudi M, Sherwood CC. Adult neurogenesis and "immature" neurons in mammals: an evolutionary trade-off in plasticity? Brain Struct Funct 2023:10.1007/s00429-023-02717-9. [PMID: 37833544 DOI: 10.1007/s00429-023-02717-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Accepted: 09/26/2023] [Indexed: 10/15/2023]
Abstract
Neuronal plasticity can vary remarkably in its form and degree across animal species. Adult neurogenesis, namely the capacity to produce new neurons from neural stem cells through adulthood, appears widespread in non-mammalian vertebrates, whereas it is reduced in mammals. A growing body of comparative studies also report variation in the occurrence and activity of neural stem cell niches between mammals, with a general trend of reduction from small-brained to large-brained species. Conversely, recent studies have shown that large-brained mammals host large amounts of neurons expressing typical markers of neurogenesis in the absence of cell division. In layer II of the cerebral cortex, populations of prenatally generated, non-dividing neurons continue to express molecules indicative of immaturity throughout life (cortical immature neurons; cINs). After remaining in a dormant state for a very long time, these cINs retain the potential of differentiating into mature neurons that integrate within the preexisting neural circuits. They are restricted to the paleocortex in small-brained rodents, while extending into the widely expanded neocortex of highly gyrencephalic, large-brained species. The current hypothesis is that these populations of non-newly generated "immature" neurons might represent a reservoir of developmentally plastic cells for mammalian species that are characterized by reduced stem cell-driven adult neurogenesis. This indicates that there may be a trade-off between various forms of plasticity that coexist during brain evolution. This balance may be necessary to maintain a "reservoir of plasticity" in brain regions that have distinct roles in species-specific socioecological adaptations, such as the neocortex and olfactory structures.
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Affiliation(s)
- Luca Bonfanti
- Neuroscience Institute Cavalieri Ottolenghi, Orbassano, Italy.
- Department of Veterinary Sciences, University of Turin, Largo Braccini 2, 10095, Turin, Grugliasco, Italy.
| | - Chiara La Rosa
- Neuroscience Institute Cavalieri Ottolenghi, Orbassano, Italy
| | - Marco Ghibaudi
- Neuroscience Institute Cavalieri Ottolenghi, Orbassano, Italy
- Department of Veterinary Sciences, University of Turin, Largo Braccini 2, 10095, Turin, Grugliasco, Italy
| | - Chet C Sherwood
- Department of Anthropology and Center for the Advanced Study of Human Paleobiology, The George Washington University, Washington, DC, USA.
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Zeppilli S, Gurrola AO, Demetci P, Brann DH, Attey R, Zilkha N, Kimchi T, Datta SR, Singh R, Tosches MA, Crombach A, Fleischmann A. Mammalian olfactory cortex neurons retain molecular signatures of ancestral cell types. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.13.553130. [PMID: 37645751 PMCID: PMC10461972 DOI: 10.1101/2023.08.13.553130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
The cerebral cortex diversified extensively during vertebrate evolution. Intriguingly, the three-layered mammalian olfactory cortex resembles the cortical cytoarchitecture of non-mammals yet evolved alongside the six-layered neocortex, enabling unique comparisons for investigating cortical neuron diversification. We performed single-nucleus multiome sequencing across mouse three- to six-layered cortices and compared neuron types across mice, reptiles and salamander. We identified neurons that are olfactory cortex-specific or conserved across mouse cortical areas. However, transcriptomically similar neurons exhibited area-specific epigenetic states. Additionally, the olfactory cortex showed transcriptomic divergence between lab and wild-derived mice, suggesting enhanced circuit plasticity through adult immature neurons. Finally, olfactory cortex neurons displayed marked transcriptomic similarities to reptile and salamander neurons. Together, these data indicate that the mammalian olfactory cortex retains molecular signatures representative of ancestral cortical traits.
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7
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Ghibaudi M, Marchetti N, Vergnano E, La Rosa C, Benedetti B, Couillard-Despres S, Farioli-Vecchioli S, Bonfanti L. Age-related changes in layer II immature neurons of the murine piriform cortex. Front Cell Neurosci 2023; 17:1205173. [PMID: 37576566 PMCID: PMC10416627 DOI: 10.3389/fncel.2023.1205173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Accepted: 07/14/2023] [Indexed: 08/15/2023] Open
Abstract
The recent identification of a population of non-newly born, prenatally generated "immature" neurons in the layer II of the piriform cortex (cortical immature neurons, cINs), raises questions concerning their maintenance or depletion through the lifespan. Most forms of brain structural plasticity progressively decline with age, a feature that is particularly prominent in adult neurogenesis, due to stem cell depletion. By contrast, the entire population of the cINs is produced during embryogenesis. Then these cells simply retain immaturity in postnatal and adult stages, until they "awake" to complete their maturation and ultimately integrate into neural circuits. Hence, the question remains open whether the cINs, which are not dependent on stem cell division, might follow a similar pattern of age-related reduction, or in alternative, might leave a reservoir of young, undifferentiated cells in the adult and aging brain. Here, the number and features of cINs were analyzed in the mouse piriform cortex from postnatal to advanced ages, by using immunocytochemistry for the cytoskeletal marker doublecortin. The abundance and stage of maturation of cINs, along with the expression of other markers of maturity/immaturity were investigated. Despite a marked decrease in this neuronal population during juvenile stages, reminiscent of that observed in hippocampal neurogenesis, a small amount of highly immature cINs persisted up to advanced ages. Overall, albeit reducing in number with increasing age, we report that the cINs are present through the entire animal lifespan.
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Affiliation(s)
- Marco Ghibaudi
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano, Italy
- Department of Veterinary Sciences, University of Turin, Turin, Italy
| | - Nicole Marchetti
- Institute of Biochemistry and Cell Biology, National Research Council, Rome, Italy
| | - Elena Vergnano
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano, Italy
| | - Chiara La Rosa
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano, Italy
| | - Bruno Benedetti
- Institute of Experimental Neuroregeneration, Paracelsus Medical University, Salzburg, Austria
- Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), Salzburg, Austria
- Austrian Cluster for Tissue Regeneration, Vienna, Austria
| | - Sebastien Couillard-Despres
- Institute of Experimental Neuroregeneration, Paracelsus Medical University, Salzburg, Austria
- Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), Salzburg, Austria
- Austrian Cluster for Tissue Regeneration, Vienna, Austria
| | | | - Luca Bonfanti
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano, Italy
- Department of Veterinary Sciences, University of Turin, Turin, Italy
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8
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Li YN, Hu DD, Cai XL, Wang Y, Yang C, Jiang J, Zhang QL, Tu T, Wang XS, Wang H, Tu E, Wang XP, Pan A, Yan XX, Wan L. Doublecortin-Expressing Neurons in Human Cerebral Cortex Layer II and Amygdala from Infancy to 100 Years Old. Mol Neurobiol 2023; 60:3464-3485. [PMID: 36879137 DOI: 10.1007/s12035-023-03261-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 02/04/2023] [Indexed: 03/08/2023]
Abstract
A cohort of morphologically heterogenous doublecortin immunoreactive (DCX +) "immature neurons" has been identified in the cerebral cortex largely around layer II and the amygdala largely in the paralaminar nucleus (PLN) among various mammals. To gain a wide spatiotemporal view on these neurons in humans, we examined layer II and amygdalar DCX + neurons in the brains of infants to 100-year-old individuals. Layer II DCX + neurons occurred throughout the cerebrum in the infants/toddlers, mainly in the temporal lobe in the adolescents and adults, and only in the temporal cortex surrounding the amygdala in the elderly. Amygdalar DCX + neurons occurred in all age groups, localized primarily to the PLN, and reduced in number with age. The small-sized DCX + neurons were unipolar or bipolar, and formed migratory chains extending tangentially, obliquely, and inwardly in layers I-III in the cortex, and from the PLN to other nuclei in the amygdala. Morphologically mature-looking neurons had a relatively larger soma and weaker DCX reactivity. In contrast to the above, DCX + neurons in the hippocampal dentate gyrus were only detected in the infant cases in parallelly processed cerebral sections. The present study reveals a broader regional distribution of the cortical layer II DCX + neurons than previously documented in human cerebrum, especially during childhood and adolescence, while both layer II and amygdalar DCX + neurons persist in the temporal lobe lifelong. Layer II and amygdalar DCX + neurons may serve as an essential immature neuronal system to support functional network plasticity in human cerebrum in an age/region-dependent manner.
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Affiliation(s)
- Ya-Nan Li
- Department of Anatomy and Neurobiology, Central South University Xiangya Medical School, Changsha, 410013, Hunan, China
| | - Dan-Dan Hu
- Department of Anatomy and Neurobiology, Central South University Xiangya Medical School, Changsha, 410013, Hunan, China
| | - Xiao-Lu Cai
- Department of Anatomy and Neurobiology, Central South University Xiangya Medical School, Changsha, 410013, Hunan, China
| | - Yan Wang
- Department of Anatomy and Neurobiology, Central South University Xiangya Medical School, Changsha, 410013, Hunan, China
| | - Chen Yang
- Department of Anatomy and Neurobiology, Central South University Xiangya Medical School, Changsha, 410013, Hunan, China
| | - Juan Jiang
- Department of Anatomy and Neurobiology, Central South University Xiangya Medical School, Changsha, 410013, Hunan, China
| | - Qi-Lei Zhang
- Department of Anatomy and Neurobiology, Central South University Xiangya Medical School, Changsha, 410013, Hunan, China
| | - Tian Tu
- Department of Anatomy and Neurobiology, Central South University Xiangya Medical School, Changsha, 410013, Hunan, China.,Department of Neurology, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China
| | - Xiao-Sheng Wang
- Department of Anatomy and Neurobiology, Central South University Xiangya Medical School, Changsha, 410013, Hunan, China
| | - Hui Wang
- Department of Anatomy and Neurobiology, Central South University Xiangya Medical School, Changsha, 410013, Hunan, China
| | - Ewen Tu
- Department of Neurology, Brain Hospital of Hunan Province, Changsha, 410007, Hunan, China
| | - Xiao-Ping Wang
- Department of Psychiatry, The Second Xiangya Hospital, Central South University, Changsha, 410031, Hunan, China
| | - Aihua Pan
- Department of Anatomy and Neurobiology, Central South University Xiangya Medical School, Changsha, 410013, Hunan, China.
| | - Xiao-Xin Yan
- Department of Anatomy and Neurobiology, Central South University Xiangya Medical School, Changsha, 410013, Hunan, China
| | - Lily Wan
- Department of Anatomy and Neurobiology, Central South University Xiangya Medical School, Changsha, 410013, Hunan, China.
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9
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Ghibaudi M, Amenta A, Agosti M, Riva M, Graïc JM, Bifari F, Bonfanti L. Consistency and Variation in Doublecortin and Ki67 Antigen Detection in the Brain Tissue of Different Mammals, including Humans. Int J Mol Sci 2023; 24:2514. [PMID: 36768845 PMCID: PMC9916846 DOI: 10.3390/ijms24032514] [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: 12/16/2022] [Revised: 01/10/2023] [Accepted: 01/12/2023] [Indexed: 01/31/2023] Open
Abstract
Recently, a population of "immature" neurons generated prenatally, retaining immaturity for long periods and finally integrating in adult circuits has been described in the cerebral cortex. Moreover, comparative studies revealed differences in occurrence/rate of different forms of neurogenic plasticity across mammals, the "immature" neurons prevailing in gyrencephalic species. To extend experimentation from laboratory mice to large-brained mammals, including humans, it is important to detect cell markers of neurogenic plasticity in brain tissues obtained from different procedures (e.g., post-mortem/intraoperative specimens vs. intracardiac perfusion). This variability overlaps with species-specific differences in antigen distribution or antibody species specificity, making it difficult for proper comparison. In this work, we detect the presence of doublecortin and Ki67 antigen, markers for neuronal immaturity and cell division, in six mammals characterized by widely different brain size. We tested seven commercial antibodies in four selected brain regions known to host immature neurons (paleocortex, neocortex) and newly born neurons (hippocampus, subventricular zone). In selected human brains, we confirmed the specificity of DCX antibody by performing co-staining with fluorescent probe for DCX mRNA. Our results indicate that, in spite of various types of fixations, most differences were due to the use of different antibodies and the existence of real interspecies variation.
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Affiliation(s)
- Marco Ghibaudi
- Neuroscience Institute Cavalieri Ottolenghi (NICO), 10043 Orbassano, Italy
- Department of Veterinary Sciences, University of Turin, 10095 Torino, Italy
| | - Alessia Amenta
- Laboratory of Cell Metabolism and Regenerative Medicine, Department of Medical Biotechnology and Translational Medicine, University of Milan, 20133 Milan, Italy
| | - Miriam Agosti
- Laboratory of Cell Metabolism and Regenerative Medicine, Department of Medical Biotechnology and Translational Medicine, University of Milan, 20133 Milan, Italy
| | - Marco Riva
- Department of Biomedical Sciences, Humanitas University, 20090 Pieve Emanuele, Italy
- IRCCS Humanitas Research Hospital, 20089 Rozzano, Italy
| | - Jean-Marie Graïc
- Department of Comparative Biomedicine and Food Science, University of Padova, 35020 Legnaro, Italy
| | - Francesco Bifari
- Laboratory of Cell Metabolism and Regenerative Medicine, Department of Medical Biotechnology and Translational Medicine, University of Milan, 20133 Milan, Italy
| | - Luca Bonfanti
- Neuroscience Institute Cavalieri Ottolenghi (NICO), 10043 Orbassano, Italy
- Department of Veterinary Sciences, University of Turin, 10095 Torino, Italy
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10
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Yan M, Xiong M, Wu Y, Lin D, Chen P, Chen J, Liu Z, Zhang H, Ren D, Fei E, Lai X, Zou S, Wang S. LRP4 is required for the olfactory association task in the piriform cortex. Cell Biosci 2022; 12:54. [PMID: 35526070 PMCID: PMC9080164 DOI: 10.1186/s13578-022-00792-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Accepted: 04/18/2022] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Low-density lipoprotein receptor-related protein 4 (LRP4) plays a critical role in the central nervous system (CNS), including hippocampal synaptic plasticity, maintenance of excitatory synaptic transmission, fear regulation, as well as long-term potentiation (LTP).
Results
In this study, we found that Lrp4 was highly expressed in layer II of the piriform cortex. Both body weight and brain weight decreased in Lrp4ECD/ECD mice without TMD (Transmembrane domain) and ICD (intracellular domain) of LRP4. However, in the piriform cortical neurons of Lrp4ECD/ECD mice, the spine density increased, and the frequency of both mEPSC (miniature excitatory postsynaptic current) and sEPSC (spontaneous excitatory postsynaptic current) was enhanced. Intriguingly, finding food in the buried food-seeking test was prolonged in both Lrp4ECD/ECD mice and Lrp4 cKO (conditional knockout of Lrp4 in the piriform cortex) mice.
Conclusions
This study indicated that the full length of LRP4 in the piriform cortex was necessary for maintaining synaptic plasticity and the integrity of olfactory function.
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11
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Porter DDL, Henry SN, Ahmed S, Rizzo AL, Makhlouf R, Gregg C, Morton PD. Neuroblast migration along cellular substrates in the developing porcine brain. Stem Cell Reports 2022; 17:2097-2110. [PMID: 35985331 PMCID: PMC9481921 DOI: 10.1016/j.stemcr.2022.07.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 07/22/2022] [Accepted: 07/23/2022] [Indexed: 11/27/2022] Open
Abstract
In the past decade it has become evident that neuroblasts continue to supply the human cortex with interneurons via unique migratory streams shortly following birth. Owing to the size of the human brain, these newborn neurons must migrate long distances through complex cellular landscapes to reach their final locations. This process is poorly understood, largely because of technical difficulties in acquiring and studying neurotypical postmortem human samples along with diverging developmental features of well-studied mouse models. We reasoned that migratory streams of neuroblasts utilize cellular substrates, such as blood vessels, to guide their trek from the subventricular zone to distant cortical targets. Here, we evaluate the association between young interneuronal migratory streams and their preferred cellular substrates in gyrencephalic piglets during the developmental equivalent of human birth, infancy, and toddlerhood. Migratory streams of neuroblasts are preserved through postnatal swine development Evidence of young neocortical interneurons within migratory streams Neuroblasts are tightly associated with vascular and astrocytic cellular substrates Harm to migratory interneurons or their substrates may have lifelong consequences
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Affiliation(s)
- Demisha D L Porter
- Virginia Tech Graduate Program in Translational Biology, Medicine and Health, Virginia Polytechnic Institute and State University, Roanoke, VA, USA; Department of Biological Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Sara N Henry
- Department of Biological Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Sadia Ahmed
- Department of Biological Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Amy L Rizzo
- Office of the University Veterinarian & Animal Resources, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Rita Makhlouf
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Collin Gregg
- Virginia Tech Graduate Program in Translational Biology, Medicine and Health, Virginia Polytechnic Institute and State University, Roanoke, VA, USA
| | - Paul D Morton
- Department of Biological Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA.
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12
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Immature excitatory neurons in the amygdala come of age during puberty. Dev Cogn Neurosci 2022; 56:101133. [PMID: 35841648 PMCID: PMC9289873 DOI: 10.1016/j.dcn.2022.101133] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 06/23/2022] [Accepted: 07/08/2022] [Indexed: 11/21/2022] Open
Abstract
The human amygdala is critical for emotional learning, valence coding, and complex social interactions, all of which mature throughout childhood, puberty, and adolescence. Across these ages, the amygdala paralaminar nucleus (PL) undergoes significant structural changes including increased numbers of mature neurons. The PL contains a large population of immature excitatory neurons at birth, some of which may continue to be born from local progenitors. These progenitors disappear rapidly in infancy, but the immature neurons persist throughout childhood and adolescent ages, indicating that they develop on a protracted timeline. Many of these late-maturing neurons settle locally within the PL, though a small subset appear to migrate into neighboring amygdala subnuclei. Despite its prominent growth during postnatal life and possible contributions to multiple amygdala circuits, the function of the PL remains unknown. PL maturation occurs predominately during late childhood and into puberty when sex hormone levels change. Sex hormones can promote developmental processes such as neuron migration, dendritic outgrowth, and synaptic plasticity, which appear to be ongoing in late-maturing PL neurons. Collectively, we describe how the growth of late-maturing neurons occurs in the right time and place to be relevant for amygdala functions and neuropsychiatric conditions.
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13
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Ghibaudi M, Bonfanti L. How Widespread Are the “Young” Neurons of the Mammalian Brain? Front Neurosci 2022; 16:918616. [PMID: 35733930 PMCID: PMC9207312 DOI: 10.3389/fnins.2022.918616] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 05/17/2022] [Indexed: 12/14/2022] Open
Abstract
After the discovery of adult neurogenesis (stem cell-driven production of new neuronal elements), it is conceivable to find young, undifferentiated neurons mixed with mature neurons in the neural networks of the adult mammalian brain. This “canonical” neurogenesis is restricted to small stem cell niches persisting from embryonic germinal layers, yet, the genesis of new neurons has also been reported in various parenchymal brain regions. Whichever the process involved, several populations of “young” neurons can be found at different locations of the brain. Across the years, further complexity emerged: (i) molecules of immaturity can also be expressed by non-dividing cells born during embryogenesis, then maintaining immature features later on; (ii) remarkable interspecies differences exist concerning the types, location, amount of undifferentiated neurons; (iii) re-expression of immaturity can occur in aging (dematuration). These twists are introducing a somewhat different definition of neurogenesis than normally assumed, in which our knowledge of the “young” neurons is less sharp. In this emerging complexity, there is a need for complete mapping of the different “types” of young neurons, considering their role in postnatal development, plasticity, functioning, and interspecies differences. Several important aspects are at stake: the possible role(s) that the young neurons may play in maintaining brain efficiency and in prevention/repair of neurological disorders; nonetheless, the correct translation of results obtained from laboratory rodents. Hence, the open question is: how many types of undifferentiated neurons do exist in the brain, and how widespread are they?
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Affiliation(s)
- Marco Ghibaudi
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano, Italy
- Department of Veterinary Sciences, University of Turin, Grugliasco, Italy
| | - Luca Bonfanti
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano, Italy
- Department of Veterinary Sciences, University of Turin, Grugliasco, Italy
- *Correspondence: Luca Bonfanti,
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14
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Roeder SS, Burkardt P, Rost F, Rode J, Brusch L, Coras R, Englund E, Håkansson K, Possnert G, Salehpour M, Primetzhofer D, Csiba L, Molnár S, Méhes G, Tonchev AB, Schwab S, Bergmann O, Huttner HB. Evidence for postnatal neurogenesis in the human amygdala. Commun Biol 2022; 5:366. [PMID: 35440676 PMCID: PMC9018740 DOI: 10.1038/s42003-022-03299-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 03/22/2022] [Indexed: 12/12/2022] Open
Abstract
The human amygdala is involved in processing of memory, decision-making, and emotional responses. Previous studies suggested that the amygdala may represent a neurogenic niche in mammals. By combining two distinct methodological approaches, lipofuscin quantification and 14C-based retrospective birth dating of neurons, along with mathematical modelling, we here explored whether postnatal neurogenesis exists in the human amygdala. We investigated post-mortem samples of twelve neurologically healthy subjects. The average rate of lipofuscin-negative neurons was 3.4%, representing a substantial proportion of cells substantially younger than the individual. Mass spectrometry analysis of genomic 14C-concentrations in amygdala neurons compared with atmospheric 14C-levels provided evidence for postnatal neuronal exchange. Mathematical modelling identified a best-fitting scenario comprising of a quiescent and a renewing neuronal population with an overall renewal rate of >2.7% per year. In conclusion, we provide evidence for postnatal neurogenesis in the human amygdala with cell turnover rates comparable to the hippocampus. Lipofuscin labeling and 14 C retrospective birth-dating of neurons, along with mathematical modelling, here suggest continued postnatal neurogenesis in the human amygdala, rather than protracted maturation of developmentally generated neurons.
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Affiliation(s)
- Sebastian S Roeder
- Department of Neurology, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Petra Burkardt
- Department of Neurology, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Fabian Rost
- Center for Regenerative Therapies (CRTD), TU Dresden, Dresden, Germany.,Max Planck Institute for the Physics of Complex Systems, Dresden, Germany.,Center for Information Services and High Performance Computing (ZIH), TU Dresden, Dresden, Germany.,Center for Molecular and Cellular Bioengineering, DRESDEN-concept Genome Center, TU Dresden, Dresden, Germany
| | - Julian Rode
- Center for Information Services and High Performance Computing (ZIH), TU Dresden, Dresden, Germany
| | - Lutz Brusch
- Center for Information Services and High Performance Computing (ZIH), TU Dresden, Dresden, Germany
| | - Roland Coras
- Department of Neuropathology, University of Erlangen-Nuremberg, Erlangen, Germany
| | | | - Karl Håkansson
- Tandem Laboratory, Uppsala University, Uppsala, Sweden.,Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden
| | | | - Mehran Salehpour
- Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden
| | - Daniel Primetzhofer
- Tandem Laboratory, Uppsala University, Uppsala, Sweden.,Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden
| | - László Csiba
- Department of Neurology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary.,MTA-DE Cerebrovascular and Neurodegenerative Research Group, Debrecen, Hungary
| | - Sarolta Molnár
- Department of Pathology, University of Debrecen, Debrecen, Hungary
| | - Gábor Méhes
- Department of Pathology, University of Debrecen, Debrecen, Hungary
| | - Anton B Tonchev
- Departments of Anatomy, Cell Biology and Stem Cell Biology, Medical University Varna, Varna, Bulgaria
| | - Stefan Schwab
- Department of Neurology, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Olaf Bergmann
- Center for Regenerative Therapies (CRTD), TU Dresden, Dresden, Germany.,Department of Cell and Molecular Biology, Karolinska Institute, Stockholm, Sweden
| | - Hagen B Huttner
- Department of Neurology, University of Erlangen-Nuremberg, Erlangen, Germany. .,Department of Neurology, Justus Liebig University Giessen, Giessen, Germany.
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15
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Benedetti B, Couillard-Despres S. Why Would the Brain Need Dormant Neuronal Precursors? Front Neurosci 2022; 16:877167. [PMID: 35464307 PMCID: PMC9026174 DOI: 10.3389/fnins.2022.877167] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 03/11/2022] [Indexed: 12/13/2022] Open
Abstract
Dormant non-proliferative neuronal precursors (dormant precursors) are a unique type of undifferentiated neuron, found in the adult brain of several mammalian species, including humans. Dormant precursors are fundamentally different from canonical neurogenic-niche progenitors as they are generated exquisitely during the embryonic development and maintain a state of protracted postmitotic immaturity lasting up to several decades after birth. Thus, dormant precursors are not pluripotent progenitors, but to all effects extremely immature neurons. Recently, transgenic models allowed to reveal that with age virtually all dormant precursors progressively awaken, abandon the immature state, and become fully functional neurons. Despite the limited common awareness about these cells, the deep implications of recent discoveries will likely lead to revisit our understanding of the adult brain. Thus, it is timely to revisit and critically assess the essential evidences that help pondering on the possible role(s) of these cells in relation to cognition, aging, and pathology. By highlighting pivoting findings as well as controversies and open questions, we offer an exciting perspective over the field of research that studies these mysterious cells and suggest the next steps toward the answer of a crucial question: why does the brain need dormant neuronal precursors?
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Affiliation(s)
- Bruno Benedetti
- Institute of Experimental Neuroregeneration, Paracelsus Medical University, Salzburg, Austria
- Spinal Cord Injury and Tissue Regeneration Center Salzburg, Paracelsus Medical University, Salzburg, Austria
- Austrian Cluster for Tissue Regeneration, Vienna, Austria
| | - Sebastien Couillard-Despres
- Institute of Experimental Neuroregeneration, Paracelsus Medical University, Salzburg, Austria
- Spinal Cord Injury and Tissue Regeneration Center Salzburg, Paracelsus Medical University, Salzburg, Austria
- Austrian Cluster for Tissue Regeneration, Vienna, Austria
- *Correspondence: Sebastien Couillard-Despres,
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16
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Coviello S, Gramuntell Y, Klimczak P, Varea E, Blasco-Ibañez JM, Crespo C, Gutierrez A, Nacher J. Phenotype and Distribution of Immature Neurons in the Human Cerebral Cortex Layer II. Front Neuroanat 2022; 16:851432. [PMID: 35464133 PMCID: PMC9027810 DOI: 10.3389/fnana.2022.851432] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Accepted: 03/22/2022] [Indexed: 11/13/2022] Open
Abstract
This work provides evidence of the presence of immature neurons in the human brain, specifically in the layer II of the cerebral cortex. Using surgical samples from epileptic patients and post-mortem tissue, we have found cells with different levels of dendritic complexity (type I and type II cells) expressing DCX and PSA-NCAM and lacking expression of the mature neuronal marker NeuN. These immature cells belonged to the excitatory lineage, as demonstrated both by the expression of CUX1, CTIP2, and TBR1 transcription factors and by the lack of the inhibitory marker GAD67. The type II cells had some puncta expressing inhibitory and excitatory synaptic markers apposed to their perisomatic and peridendritic regions and ultrastructural analysis suggest the presence of synaptic contacts. These cells did not present glial cell markers, although astroglial and microglial processes were found in close apposition to their somata and dendrites, particularly on type I cells. Our findings confirm the presence of immature neurons in several regions of the cerebral cortex of humans of different ages and define their lineage. The presence of some mature features in some of these cells suggests the possibility of a progressively integration as excitatory neurons, as described in the olfactory cortex of rodents.
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Affiliation(s)
- Simona Coviello
- Neurobiology Unit, Program in Neurosciences and Institute of Biotechnology and Biomedicine (BIOTECMED), Universitat de València, Burjassot, Spain
| | - Yaiza Gramuntell
- Neurobiology Unit, Program in Neurosciences and Institute of Biotechnology and Biomedicine (BIOTECMED), Universitat de València, Burjassot, Spain
| | - Patrycja Klimczak
- Neurobiology Unit, Program in Neurosciences and Institute of Biotechnology and Biomedicine (BIOTECMED), Universitat de València, Burjassot, Spain
- Spanish National Network for Research in Mental Health, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain
| | - Emilio Varea
- Neurobiology Unit, Program in Neurosciences and Institute of Biotechnology and Biomedicine (BIOTECMED), Universitat de València, Burjassot, Spain
| | - José Miguel Blasco-Ibañez
- Neurobiology Unit, Program in Neurosciences and Institute of Biotechnology and Biomedicine (BIOTECMED), Universitat de València, Burjassot, Spain
| | - Carlos Crespo
- Neurobiology Unit, Program in Neurosciences and Institute of Biotechnology and Biomedicine (BIOTECMED), Universitat de València, Burjassot, Spain
| | - Antonio Gutierrez
- Unidad de Cirugía de la Epilepsia, Hospital Universitario La Fe, Valencia, Spain
| | - Juan Nacher
- Neurobiology Unit, Program in Neurosciences and Institute of Biotechnology and Biomedicine (BIOTECMED), Universitat de València, Burjassot, Spain
- Spanish National Network for Research in Mental Health, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain
- Fundación Investigación Hospital Clínico de Valencia (INCLIVA), Valencia, Spain
- *Correspondence: Juan Nacher,
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17
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Sánchez-González R, López-Mascaraque L. Lineage Relationships Between Subpallial Progenitors and Glial Cells in the Piriform Cortex. Front Neurosci 2022; 16:825969. [PMID: 35386594 PMCID: PMC8979001 DOI: 10.3389/fnins.2022.825969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 01/21/2022] [Indexed: 11/22/2022] Open
Abstract
The piriform cortex is a paleocortical area, located in the ventrolateral surface of the rodent forebrain, receiving direct input from the olfactory bulb. The three layers of the PC are defined by the diversity of glial and neuronal cells, marker expression, connections, and functions. However, the glial layering, ontogeny, and sibling cell relationship along the PC is an unresolved question in the field. Here, using multi-color genetic lineage tracing approaches with different StarTrack strategies, we performed a rigorous analysis of the derived cell progenies from progenitors located at the subpallium ventricular surface. First, we specifically targeted E12-progenitors with UbC-StarTrack to analyze their adult derived-cell progeny and their location within the piriform cortex layers. The vast majority of the cell progeny derived from targeted progenitors were identified as neurons, but also astrocytes and NG2 cells. Further, to specifically target single Gsx-2 subpallial progenitors and their derived cell-progeny in the piriform cortex, we used the UbC-(Gsx-2-hyPB)-StarTrack to perform an accurate analysis of their clonal relationships. Our results quantitatively delineate the adult clonal cell pattern from single subpallial E12-progenitors, focusing on glial cells. In summary, there is a temporal pattern in the assembly of the glial cell diversity in the piriform cortex, which also reveals spatio-temporal progenitor heterogeneity.
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18
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Franjic D, Skarica M, Ma S, Arellano JI, Tebbenkamp ATN, Choi J, Xu C, Li Q, Morozov YM, Andrijevic D, Vrselja Z, Spajic A, Santpere G, Li M, Zhang S, Liu Y, Spurrier J, Zhang L, Gudelj I, Rapan L, Takahashi H, Huttner A, Fan R, Strittmatter SM, Sousa AMM, Rakic P, Sestan N. Transcriptomic taxonomy and neurogenic trajectories of adult human, macaque, and pig hippocampal and entorhinal cells. Neuron 2022; 110:452-469.e14. [PMID: 34798047 PMCID: PMC8813897 DOI: 10.1016/j.neuron.2021.10.036] [Citation(s) in RCA: 125] [Impact Index Per Article: 62.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 10/17/2021] [Accepted: 10/26/2021] [Indexed: 02/04/2023]
Abstract
The hippocampal-entorhinal system supports cognitive functions, has lifelong neurogenic capabilities in many species, and is selectively vulnerable to Alzheimer's disease. To investigate neurogenic potential and cellular diversity, we profiled single-nucleus transcriptomes in five hippocampal-entorhinal subregions in humans, macaques, and pigs. Integrated cross-species analysis revealed robust transcriptomic and histologic signatures of neurogenesis in the adult mouse, pig, and macaque but not humans. Doublecortin (DCX), a widely accepted marker of newly generated granule cells, was detected in diverse human neurons, but it did not define immature neuron populations. To explore species differences in cellular diversity and implications for disease, we characterized subregion-specific, transcriptomically defined cell types and transitional changes from the three-layered archicortex to the six-layered neocortex. Notably, METTL7B defined subregion-specific excitatory neurons and astrocytes in primates, associated with endoplasmic reticulum and lipid droplet proteins, including Alzheimer's disease-related proteins. This resource reveals cell-type- and species-specific properties shaping hippocampal-entorhinal neurogenesis and function.
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Affiliation(s)
- Daniel Franjic
- Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Mario Skarica
- Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Shaojie Ma
- Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA; Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA
| | - Jon I Arellano
- Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | | | - Jinmyung Choi
- Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Chuan Xu
- Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Qian Li
- Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Yury M Morozov
- Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - David Andrijevic
- Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Zvonimir Vrselja
- Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Ana Spajic
- Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Gabriel Santpere
- Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA; Neurogenomics Group, Research Programme on Biomedical Informatics (GRIB), Hospital del Mar Medical Research Institute (IMIM), DCEXS, Universitat Pompeu Fabra, 08003 Barcelona, Catalonia, Spain
| | - Mingfeng Li
- Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Shupei Zhang
- Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Yang Liu
- Department of Biomedical Engineering, Yale Stem Cell Center and Yale Cancer Center, and Human and Translational Immunology Program, Yale University, New Haven, CT 06520, USA
| | - Joshua Spurrier
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Departments of Neurology and of Neuroscience, Yale School of Medicine, New Haven, CT 06536, USA
| | - Le Zhang
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Departments of Neurology and of Neuroscience, Yale School of Medicine, New Haven, CT 06536, USA
| | - Ivan Gudelj
- Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Lucija Rapan
- Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Hideyuki Takahashi
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Departments of Neurology and of Neuroscience, Yale School of Medicine, New Haven, CT 06536, USA
| | - Anita Huttner
- Department of Pathology, Brady Memorial Laboratory, Yale School of Medicine, New Haven, CT 06510, USA
| | - Rong Fan
- Department of Biomedical Engineering, Yale Stem Cell Center and Yale Cancer Center, and Human and Translational Immunology Program, Yale University, New Haven, CT 06520, USA
| | - Stephen M Strittmatter
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Departments of Neurology and of Neuroscience, Yale School of Medicine, New Haven, CT 06536, USA
| | - Andre M M Sousa
- Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA; Waisman Center and Department of Neuroscience, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Pasko Rakic
- Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA; Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Nenad Sestan
- Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA; Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA; Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA; Departments of Psychiatry and Comparative Medicine, Program in Cellular Neuroscience, Neurodegeneration and Repair, and Yale Child Study Center, Yale School of Medicine, New Haven, CT 06510, USA.
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19
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Bonfanti L, Seki T. The PSA-NCAM-Positive "Immature" Neurons: An Old Discovery Providing New Vistas on Brain Structural Plasticity. Cells 2021; 10:2542. [PMID: 34685522 PMCID: PMC8534119 DOI: 10.3390/cells10102542] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 09/14/2021] [Accepted: 09/24/2021] [Indexed: 01/18/2023] Open
Abstract
Studies on brain plasticity have undertaken different roads, tackling a wide range of biological processes: from small synaptic changes affecting the contacts among neurons at the very tip of their processes, to birth, differentiation, and integration of new neurons (adult neurogenesis). Stem cell-driven adult neurogenesis is an exception in the substantially static mammalian brain, yet, it has dominated the research in neurodevelopmental biology during the last thirty years. Studies of comparative neuroplasticity have revealed that neurogenic processes are reduced in large-brained mammals, including humans. On the other hand, large-brained mammals, with respect to rodents, host large populations of special "immature" neurons that are generated prenatally but express immature markers in adulthood. The history of these "immature" neurons started from studies on adhesion molecules carried out at the beginning of the nineties. The identity of these neurons as "stand by" cells "frozen" in a state of immaturity remained un-detected for long time, because of their ill-defined features and because clouded by research ef-forts focused on adult neurogenesis. In this review article, the history of these cells will be reconstructed, and a series of nuances and confounding factors that have hindered the distinction between newly generated and "immature" neurons will be addressed.
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Affiliation(s)
- Luca Bonfanti
- Neuroscience Institute Cavalieri Ottolenghi (NICO), 10043 Orbassano, Italy
- Department of Veterinary Sciences, University of Turin, 10095 Torino, Italy
| | - Tatsunori Seki
- Department of Histology and Neuroanatomy, Tokyo Medical University, Tokyo 160-8402, Japan
- Department of Anatomy and Life Structure, Juntendo University Graduate School of Medicine, Tokyo 160-8402, Japan
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20
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Bonfanti L, Charvet CJ. Brain Plasticity in Humans and Model Systems: Advances, Challenges, and Future Directions. Int J Mol Sci 2021; 22:9358. [PMID: 34502267 PMCID: PMC8431131 DOI: 10.3390/ijms22179358] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 08/26/2021] [Accepted: 08/26/2021] [Indexed: 12/20/2022] Open
Abstract
Plasticity, and in particular, neurogenesis, is a promising target to treat and prevent a wide variety of diseases (e.g., epilepsy, stroke, dementia). There are different types of plasticity, which vary with age, brain region, and species. These observations stress the importance of defining plasticity along temporal and spatial dimensions. We review recent studies focused on brain plasticity across the lifespan and in different species. One main theme to emerge from this work is that plasticity declines with age but that we have yet to map these different forms of plasticity across species. As part of this effort, we discuss our recent progress aimed to identify corresponding ages across species, and how this information can be used to map temporal variation in plasticity from model systems to humans.
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Affiliation(s)
- Luca Bonfanti
- Department of Veterinary Sciences, University of Turin, Largo Braccini 2, 10095 Grugliasco, TO, Italy
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Regione Gonzole 10, 10043 Orbassano, TO, Italy
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21
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Li X, Lin G, Liu T, Zhao N, Xu H, Wang H, Zheng W. Postnatal development of BAG3 expression in mouse cerebral cortex and hippocampus. Brain Struct Funct 2021; 226:2629-2650. [PMID: 34357438 DOI: 10.1007/s00429-021-02356-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 07/26/2021] [Indexed: 10/20/2022]
Abstract
The decreased efficiency of autophagic processing in the central nervous system during aging may be a contributing factor in neurodegenerative diseases. BAG3 (Bcl2 associated athanogene 3) is a major member of the BAG family of co-molecular chaperones that mediate selective macroautophagy. Therefore, we analyzed the expression and distribution of BAG3 in the brain at postnatal 0 day (P0), P15, 1-, 2-, 9-, 12-, and 18 month-old C57BL/6 mice, thus covering almost all ages. Except for a significant steep drop in mRNA and protein levels in the cortex and hippocampus soon after birth, there were minimal differences in the expression and distribution of BAG3 among P15, M1, M2, M9, and M12 mice; however, at 18 months, BAG3 expression was significantly higher. Immunohistochemical analyses showed that BAG3 is mainly located in the neuronal cytoplasm and processes in C57BL/6 the cerebral cortex and hippocampus from P0 to M18 postnatal development. These findings indicate that BAG3 might be stable in young and middle-aged mice, but unstable in aged mice.
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Affiliation(s)
- Xinlu Li
- Department of Histology and Embryology, China Medical University, Shenyang, 110122, China
| | - Geng Lin
- Department of Histology and Embryology, China Medical University, Shenyang, 110122, China
| | - Tongtong Liu
- Department of Histology and Embryology, China Medical University, Shenyang, 110122, China.,Department of Neurology, The People's Hospital of Liaoning Province, Shenyang, 110016, China
| | - Ning Zhao
- Department of Infectious Diseases, Shengjing Hospital, Affiliated Hospital of China Medical University, Shenyang, 110022, China
| | - He Xu
- Department of Histology and Embryology, School of Medicine, Shenzhen University, Shenzhen, 518052, China
| | - Huaqin Wang
- Department of Biochemistry and Molecular Biology, China Medical University, Shenyang, 110122, China
| | - Wei Zheng
- Department of Histology and Embryology, China Medical University, Shenyang, 110122, China.
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22
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Coviello S, Benedetti B, Jakubecova D, Belles M, Klimczak P, Gramuntell Y, Couillard-Despres S, Nacher J. PSA Depletion Induces the Differentiation of Immature Neurons in the Piriform Cortex of Adult Mice. Int J Mol Sci 2021; 22:5733. [PMID: 34072166 PMCID: PMC8198564 DOI: 10.3390/ijms22115733] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 05/10/2021] [Accepted: 05/11/2021] [Indexed: 12/12/2022] Open
Abstract
Immature neurons are maintained in cortical regions of the adult mammalian brain. In rodents, many of these immature neurons can be identified in the piriform cortex based on their high expression of early neuronal markers, such as doublecortin (DCX) and the polysialylated form of the neural cell adhesion molecule (PSA-NCAM). This molecule plays critical roles in different neurodevelopmental events. Taking advantage of a DCX-CreERT2/Flox-EGFP reporter mice, we investigated the impact of targeted PSA enzymatic depletion in the piriform cortex on the fate of immature neurons. We report here that the removal of PSA accelerated the final development of immature neurons. This was revealed by a higher frequency of NeuN expression, an increase in the number of cells carrying an axon initial segment (AIS), and an increase in the number of dendrites and dendritic spines on the immature neurons. Taken together, our results demonstrated the crucial role of the PSA moiety in the protracted development of immature neurons residing outside of the neurogenic niches. More studies will be required to understand the intrinsic and extrinsic factors affecting PSA-NCAM expression to understand how the brain regulates the incorporation of these immature neurons to the established neuronal circuits of the adult brain.
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Affiliation(s)
- Simona Coviello
- Neurobiology Unit, Program in Neurosciences and Institute of Biotechnology and Biomedicine (BIOTECMED), Universitat de València, 46100 Burjassot, Spain; (S.C.); (M.B.); (P.K.); (Y.G.)
| | - Bruno Benedetti
- Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), Institute of Experimental Neuroregeneration, Paracelsus Medical University, 5020 Salzburg, Austria; (B.B.); (D.J.)
- Austrian Cluster for Tissue Regeneration, 1200 Vienna, Austria
| | - Dominika Jakubecova
- Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), Institute of Experimental Neuroregeneration, Paracelsus Medical University, 5020 Salzburg, Austria; (B.B.); (D.J.)
| | - Maria Belles
- Neurobiology Unit, Program in Neurosciences and Institute of Biotechnology and Biomedicine (BIOTECMED), Universitat de València, 46100 Burjassot, Spain; (S.C.); (M.B.); (P.K.); (Y.G.)
| | - Patrycja Klimczak
- Neurobiology Unit, Program in Neurosciences and Institute of Biotechnology and Biomedicine (BIOTECMED), Universitat de València, 46100 Burjassot, Spain; (S.C.); (M.B.); (P.K.); (Y.G.)
| | - Yaiza Gramuntell
- Neurobiology Unit, Program in Neurosciences and Institute of Biotechnology and Biomedicine (BIOTECMED), Universitat de València, 46100 Burjassot, Spain; (S.C.); (M.B.); (P.K.); (Y.G.)
| | - Sebastien Couillard-Despres
- Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), Institute of Experimental Neuroregeneration, Paracelsus Medical University, 5020 Salzburg, Austria; (B.B.); (D.J.)
- Austrian Cluster for Tissue Regeneration, 1200 Vienna, Austria
| | - Juan Nacher
- Neurobiology Unit, Program in Neurosciences and Institute of Biotechnology and Biomedicine (BIOTECMED), Universitat de València, 46100 Burjassot, Spain; (S.C.); (M.B.); (P.K.); (Y.G.)
- Spanish National Network for Research in Mental Health (CIBERSAM), 28029 Madrid, Spain
- Fundación Investigación Hospital Clínico de Valencia, INCLIVA, 46010 Valencia, Spain
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23
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Affiliation(s)
- Chiara La Rosa
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano, Italy
| | - Luca Bonfanti
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano; Department of Veterinary Sciences, University of Turin, Grugliasco, Italy
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24
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Piriform cortex alterations in the Ts65Dn model for down syndrome. Brain Res 2020; 1747:147031. [PMID: 32726601 DOI: 10.1016/j.brainres.2020.147031] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 07/02/2020] [Accepted: 07/22/2020] [Indexed: 11/22/2022]
Abstract
The piriform cortex is involved in olfactory information processing, that is altered in Down Syndrome. Moreover, piriform cortex has a crucial involvement in epilepsy generation and is one of the first regions affected in Alzheimer's Disease, both maladies being prevalent among Down Syndrome individuals. In this work, we studied the alterations in neuronal morphology, synaptology and structural plasticity in the piriform cortex of the Ts65Dn mouse model, which is the most used model for the study of this syndrome and mimics some of their alterations. We have observed that Ts65Dn piriform cortex displays: a reduction in dendritic arborisation, a higher density of inhibitory synapses (GAD67), a lower density of excitatory synapses (vGLUT1) and a higher density of inhibitory postsynaptic puncta (gephyrin). Under electron microscopy the excitatory presynaptic and postsynaptic elements were larger in trisomic mice than in controls. Similar results were obtained using confocal microscopy. There were less immature neurons in piriform cortex layer II in addition to a reduction in the expression of PSA-NCAM in the neuropil that subsequently can reflect impairment in structural plasticity. These data support the idea of an impaired environment with altered ratio of inhibition and excitation that involves a reduction in plasticity and dendritic atrophy, providing a possible substrate for the olfactory processing impairment observed in DS individuals.
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25
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Coviello S, Gramuntell Y, Castillo-Gomez E, Nacher J. Effects of Dopamine on the Immature Neurons of the Adult Rat Piriform Cortex. Front Neurosci 2020; 14:574234. [PMID: 33122993 PMCID: PMC7573248 DOI: 10.3389/fnins.2020.574234] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 09/14/2020] [Indexed: 11/26/2022] Open
Abstract
The layer II of the adult piriform cortex (PCX) contains a numerous population of immature neurons. Interestingly, in both mice and rats, most, if not all, these cells have an embryonic origin. Moreover, recent studies from our laboratory have shown that they progressively mature into typical excitatory neurons of the PCX layer II. Therefore, the adult PCX is considered a “non-canonical” neurogenic niche. These immature neurons express the polysialylated form of the neural cell adhesion molecule (PSA-NCAM), a molecule critical for different neurodevelopmental processes. Dopamine (DA) is a relevant neurotransmitter in the adult CNS, which also plays important roles in neural development and adult plasticity, including the regulation of PSA-NCAM expression. In order to evaluate the hypothetical effects of pharmacological modulation of dopaminergic neurotransmission on the differentiation of immature neurons of the adult PCX, we studied dopamine D2 receptor (D2r) expression in this region and the relationship between dopaminergic fibers and immature neurons (defined by PSA-NCAM expression). In addition, we analyzed the density of immature neurons after chronic treatments with an antagonist and an agonist of D2r: haloperidol and PPHT, respectively. Many dopaminergic fibers were observed in close apposition to PSA-NCAM-expressing neurons, which also coexpressed D2r. Chronic treatment with haloperidol significantly increased the number of PSA-NCAM immunoreactive cells, while PPHT treatment decreased it. These results indicate a prominent role of dopamine, through D2r and PSA-NCAM, on the regulation of the final steps of development of immature neurons in the adult PCX.
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Affiliation(s)
- Simona Coviello
- Neurobiology Unit, Program in Neurosciences and Institute of Biotechnology and Biomedicine (BIOTECMED), Universitat de València, Burjassot, Spain
| | - Yaiza Gramuntell
- Neurobiology Unit, Program in Neurosciences and Institute of Biotechnology and Biomedicine (BIOTECMED), Universitat de València, Burjassot, Spain
| | - Esther Castillo-Gomez
- Department of Medicine, School of Medical Sciences, Universitat Jaume I, Castellón de la Plana, Spain.,Spanish National Network for Research in Mental Health (CIBERSAM), Madrid, Spain
| | - Juan Nacher
- Neurobiology Unit, Program in Neurosciences and Institute of Biotechnology and Biomedicine (BIOTECMED), Universitat de València, Burjassot, Spain.,Spanish National Network for Research in Mental Health (CIBERSAM), Madrid, Spain.,Fundación Investigación Hospital Clínico de Valencia, INCLIVA, Valencia, Spain
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26
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Seki T. Understanding the Real State of Human Adult Hippocampal Neurogenesis From Studies of Rodents and Non-human Primates. Front Neurosci 2020; 14:839. [PMID: 32848586 PMCID: PMC7432251 DOI: 10.3389/fnins.2020.00839] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 07/20/2020] [Indexed: 12/11/2022] Open
Abstract
The concept of adult hippocampal neurogenesis (AHN) has been widely accepted, and a large number of studies have been performed in rodents using modern experimental techniques, which have clarified the nature and developmental processes of adult neural stem/progenitor cells, the functions of AHN, such as memory and learning, and its association with neural diseases. However, a fundamental problem is that it remains unclear as to what extent AHN actually occurs in humans. The answer to this is indispensable when physiological and pathological functions of human AHN are deduced from studies of rodent AHN, but there are controversial data on the extent of human AHN. In this review, studies on AHN performed in rodents and humans will be briefly reviewed, followed by a discussion of the studies in non-human primates. Then, how data of rodent and non-human primate AHN should be applied for understanding human AHN will be discussed.
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Affiliation(s)
- Tatsunori Seki
- Department of Histology and Neuroanatomy, Tokyo Medical University, Tokyo, Japan
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27
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Abstract
Some immature neurons in the cerebral cortex of mammals might wait for years before they become activated and finish their development.
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Affiliation(s)
- Gerd Kempermann
- German Center for Neurodegenerative Diseases Dresden, TU DresdenDresdenGermany
- Center for Regenerative Therapies Dresden, TU DresdenDresdenGermany
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28
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La Rosa C, Cavallo F, Pecora A, Chincarini M, Ala U, Faulkes CG, Nacher J, Cozzi B, Sherwood CC, Amrein I, Bonfanti L. Phylogenetic variation in cortical layer II immature neuron reservoir of mammals. eLife 2020; 9:55456. [PMID: 32690132 PMCID: PMC7373429 DOI: 10.7554/elife.55456] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Accepted: 06/03/2020] [Indexed: 12/22/2022] Open
Abstract
The adult mammalian brain is mainly composed of mature neurons. A limited amount of stem cell-driven neurogenesis persists in postnatal life and is reduced in large-brained species. Another source of immature neurons in adult brains is cortical layer II. These cortical immature neurons (cINs) retain developmentally undifferentiated states in adulthood, though they are generated before birth. Here, the occurrence, distribution and cellular features of cINs were systematically studied in 12 diverse mammalian species spanning from small-lissencephalic to large-gyrencephalic brains. In spite of well-preserved morphological and molecular features, the distribution of cINs was highly heterogeneous, particularly in neocortex. While virtually absent in rodents, they are present in the entire neocortex of many other species and their linear density in cortical layer II generally increased with brain size. These findings suggest an evolutionary developmental mechanism for plasticity that varies among mammalian species, granting a reservoir of young cells for the cerebral cortex. To acquire new skills or recover after injuries, the mammalian brain relies on plasticity, the ability for the brain to change its architecture and its connections during the lifetime of an animal. Creating new nerve cells is one way to achieve plasticity, but this process is rarer in humans than it is in mammals with smaller brains. In particular, it is absent in the human cortex: this region is enlarged in species with large brains, where it carries out complex tasks such as learning and memory. Producing new cells in the cortex would threaten the stability of the structures that retain long-term memories. Another route to plasticity is to reshape the connections between existing, mature nerve cells. This process takes place in the human brain during childhood and adolescence, as some connections are strengthened and others pruned away. An alternative mechanism relies on keeping some nerve cells in an immature, ‘adolescent’ state. When needed, these nerve cells emerge from their state of arrested development and ‘grow up’, connecting with the appropriate brain circuits. This mechanism does not involve producing new nerve cells, and so it would be suitable to maintain plasticity in the cortex. Consistent with this idea, in mice some dormant nerve cells are present in a small, primitive part of the cortex. La Rosa et al. therefore wanted to determine if the location and number of immature cells in the cortex differed between mammals, and if so, whether these differences depended on brain size. The study spanned 12 mammal species, from small-brained species like mice to larger-brained animals including sheep and non-human primates. Microscopy imaging was used to identify immature nerve cells in brain samples, which revealed that the cortex in larger-brained species contained more adolescent cells than its mouse counterpart. The difference was greatest in a region called the neocortex, which has evolved most recently. This area is most pronounced in primates – especially humans – where it carries out high-level cognitive tasks. These results identify immature nerve cells as a potential mechanism for plasticity in the cortex. La Rosa et al. hope that the work will inspire searches for similar reservoirs of young cells in humans, which could perhaps lead to new treatments for brain disorders like dementia.
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Affiliation(s)
- Chiara La Rosa
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano, Italy.,Department of Veterinary Sciences, University of Turin, Torino, Italy
| | - Francesca Cavallo
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano, Italy
| | - Alessandra Pecora
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano, Italy
| | - Matteo Chincarini
- Università degli Studi di Teramo, Facoltà di Medicina Veterinaria, Teramo, Italy
| | - Ugo Ala
- Department of Veterinary Sciences, University of Turin, Torino, Italy
| | - Chris G Faulkes
- School of Biological and Chemical Sciences, Queen Mary University of London, London, United Kingdom
| | - Juan Nacher
- Neurobiology Unit, BIOTECMED, Universitat de València, and Spanish Network for Mental Health Research CIBERSAM, València, Spain
| | - Bruno Cozzi
- Department of Comparative Biomedicine and Food Science, University of Padova, Legnaro, Italy
| | - Chet C Sherwood
- Department of Anthropology and Center for the Advanced Study of Human Paleobiology, The George Washington University, Washington DC, United States
| | - Irmgard Amrein
- D-HEST, ETH, Zurich, Switzerland.,Institute of Anatomy, University of Zurich, Zurich, Switzerland
| | - Luca Bonfanti
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano, Italy.,Department of Veterinary Sciences, University of Turin, Torino, Italy
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29
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Benedetti B, Dannehl D, König R, Coviello S, Kreutzer C, Zaunmair P, Jakubecova D, Weiger TM, Aigner L, Nacher J, Engelhardt M, Couillard-Després S. Functional Integration of Neuronal Precursors in the Adult Murine Piriform Cortex. Cereb Cortex 2020; 30:1499-1515. [PMID: 31647533 PMCID: PMC7132906 DOI: 10.1093/cercor/bhz181] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 06/05/2019] [Accepted: 07/09/2019] [Indexed: 11/20/2022] Open
Abstract
The extent of functional maturation and integration of nonproliferative neuronal precursors, becoming neurons in the adult murine piriform cortex, is largely unexplored. We thus questioned whether precursors eventually become equivalent to neighboring principal neurons or whether they represent a novel functional network element. Adult brain neuronal precursors and immature neurons (complex cells) were labeled in transgenic mice (DCX-DsRed and DCX-CreERT2 /flox-EGFP), and their cell fate was characterized with patch clamp experiments and morphometric analysis of axon initial segments. Young (DCX+) complex cells in the piriform cortex of 2- to 4-month-old mice received sparse synaptic input and fired action potentials at low maximal frequency, resembling neonatal principal neurons. Following maturation, the synaptic input detected on older (DCX-) complex cells was larger, but predominantly GABAergic, despite evidence of glutamatergic synaptic contacts. Furthermore, the rheobase current of old complex cells was larger and the maximal firing frequency was lower than those measured in neighboring age-matched principal neurons. The striking differences between principal neurons and complex cells suggest that the latter are a novel type of neuron and new coding element in the adult brain rather than simple addition or replacement for preexisting network components.
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Affiliation(s)
- Bruno Benedetti
- Spinal Cord Injury and Tissue Regeneration Center Salzburg, 5020 Salzburg, Austria
- Institute of Experimental Neuroregeneration, Paracelsus Medical University, 5020 Salzburg, Austria
- Austrian Cluster for Tissue Regeneration, Vienna, Austria
| | - Dominik Dannehl
- Spinal Cord Injury and Tissue Regeneration Center Salzburg, 5020 Salzburg, Austria
- Institute of Experimental Neuroregeneration, Paracelsus Medical University, 5020 Salzburg, Austria
- Institute of Neuroanatomy, CBTM, Medical Faculty Mannheim, Heidelberg University, 68167 Mannheim, Germany
| | - Richard König
- Spinal Cord Injury and Tissue Regeneration Center Salzburg, 5020 Salzburg, Austria
- Institute of Molecular Regenerative Medicine, Paracelsus Medical University, 5020 Salzburg, Austria
| | - Simona Coviello
- BIOTECMED, Universitat de València and Center for Collaborative Research on Mental Health CIBERSAM, 46100 València, Spain
| | - Christina Kreutzer
- Spinal Cord Injury and Tissue Regeneration Center Salzburg, 5020 Salzburg, Austria
- Institute of Experimental Neuroregeneration, Paracelsus Medical University, 5020 Salzburg, Austria
- Austrian Cluster for Tissue Regeneration, Vienna, Austria
| | - Pia Zaunmair
- Spinal Cord Injury and Tissue Regeneration Center Salzburg, 5020 Salzburg, Austria
- Institute of Experimental Neuroregeneration, Paracelsus Medical University, 5020 Salzburg, Austria
- Austrian Cluster for Tissue Regeneration, Vienna, Austria
| | - Dominika Jakubecova
- Spinal Cord Injury and Tissue Regeneration Center Salzburg, 5020 Salzburg, Austria
- Institute of Experimental Neuroregeneration, Paracelsus Medical University, 5020 Salzburg, Austria
- Austrian Cluster for Tissue Regeneration, Vienna, Austria
| | - Thomas M Weiger
- Department of Biosciences, University of Salzburg, 5020 Salzburg, Austria
| | - Ludwig Aigner
- Spinal Cord Injury and Tissue Regeneration Center Salzburg, 5020 Salzburg, Austria
- Austrian Cluster for Tissue Regeneration, Vienna, Austria
- Institute of Molecular Regenerative Medicine, Paracelsus Medical University, 5020 Salzburg, Austria
| | - Juan Nacher
- BIOTECMED, Universitat de València and Center for Collaborative Research on Mental Health CIBERSAM, 46100 València, Spain
| | - Maren Engelhardt
- Institute of Neuroanatomy, CBTM, Medical Faculty Mannheim, Heidelberg University, 68167 Mannheim, Germany
| | - Sébastien Couillard-Després
- Spinal Cord Injury and Tissue Regeneration Center Salzburg, 5020 Salzburg, Austria
- Institute of Experimental Neuroregeneration, Paracelsus Medical University, 5020 Salzburg, Austria
- Austrian Cluster for Tissue Regeneration, Vienna, Austria
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30
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Zhou GP, Liao SM, Chen D, Huang RB. The Cooperative Effect between Polybasic Region (PBR) and Polysialyltransferase Domain (PSTD) within Tumor-Target Polysialyltranseferase ST8Sia II. Curr Top Med Chem 2020; 19:2831-2841. [PMID: 31755393 DOI: 10.2174/1568026619666191121145924] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2019] [Revised: 10/16/2019] [Accepted: 10/20/2019] [Indexed: 12/29/2022]
Abstract
ST8Sia II (STX) is a highly homologous mammalian polysialyltransferase (polyST), which is a validated tumor-target in the treatment of cancer metastasis reliant on tumor cell polysialylation. PolyST catalyzes the synthesis of α2,8-polysialic acid (polySia) glycans by carrying out the activated CMP-Neu5Ac (Sia) to N- and O-linked oligosaccharide chains on acceptor glycoproteins. In this review article, we summarized the recent studies about intrinsic correlation of two polybasic domains, Polysialyltransferase domain (PSTD) and Polybasic region (PBR) within ST8Sia II molecule, and suggested that the critical amino acid residues within the PSTD and PBR motifs of ST8Sia II for polysialylation of Neural cell adhesion molecules (NCAM) are related to ST8Sia II activity. In addition, the conformational changes of the PSTD domain due to point mutations in the PBR or PSTD domain verified an intramolecular interaction between the PBR and the PSTD. These findings have been incorporated into Zhou's NCAM polysialylation/cell migration model, which will provide new perspectives on drug research and development related to the tumor-target ST8Sia II.
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Affiliation(s)
- Guo-Ping Zhou
- National Engineering Research Center for Non-Food Biorefinery, State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Key Laboratory of Bio-refinery, Guangxi Academy of Sciences, 98 Daling Road, Nanning, 530007, China.,Gordon Life Science Institute, NC 27804, United States
| | - Si-Ming Liao
- National Engineering Research Center for Non-Food Biorefinery, State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Key Laboratory of Bio-refinery, Guangxi Academy of Sciences, 98 Daling Road, Nanning, 530007, China
| | - Dong Chen
- National Engineering Research Center for Non-Food Biorefinery, State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Key Laboratory of Bio-refinery, Guangxi Academy of Sciences, 98 Daling Road, Nanning, 530007, China
| | - Ri-Bo Huang
- National Engineering Research Center for Non-Food Biorefinery, State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Key Laboratory of Bio-refinery, Guangxi Academy of Sciences, 98 Daling Road, Nanning, 530007, China
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31
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La Rosa C, Parolisi R, Bonfanti L. Brain Structural Plasticity: From Adult Neurogenesis to Immature Neurons. Front Neurosci 2020; 14:75. [PMID: 32116519 PMCID: PMC7010851 DOI: 10.3389/fnins.2020.00075] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 01/20/2020] [Indexed: 12/21/2022] Open
Abstract
Brain structural plasticity is an extraordinary tool that allows the mature brain to adapt to environmental changes, to learn, to repair itself after lesions or disease, and to slow aging. A long history of neuroscience research led to fascinating discoveries of different types of plasticity, involving changes in the genetically determined structure of nervous tissue, up to the ultimate dream of neuronal replacement: a stem cell-driven “adult neurogenesis” (AN). Yet, this road does not seem a straight one, since mutable dogmas, conflicting results and conflicting interpretations continue to warm the field. As a result, after more than 10,000 papers published on AN, we still do not know its time course, rate or features with respect to other kinds of structural plasticity in our brain. The solution does not appear to be behind the next curve, as differences among mammals reveal a very complex landscape that cannot be easily understood from rodents models alone. By considering evolutionary aspects, some pitfalls in the interpretation of cell markers, and a novel population of undifferentiated cells that are not newly generated [immature neurons (INs)], we address some conflicting results and controversies in order to find the right road forward. We suggest that considering plasticity in a comparative framework might help assemble the evolutionary, anatomical and functional pieces of a very complex biological process with extraordinary translational potential.
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Affiliation(s)
- Chiara La Rosa
- Neuroscience Institute Cavalieri Ottolenghi, Orbassano, Italy.,Department of Veterinary Sciences, University of Turin, Turin, Italy
| | | | - Luca Bonfanti
- Neuroscience Institute Cavalieri Ottolenghi, Orbassano, Italy.,Department of Veterinary Sciences, University of Turin, Turin, Italy
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32
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Static Magnetic Field Exposure In Vivo Enhances the Generation of New Doublecortin-expressing Cells in the Sub-ventricular Zone and Neocortex of Adult Rats. Neuroscience 2019; 425:217-234. [PMID: 31809729 DOI: 10.1016/j.neuroscience.2019.11.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 11/01/2019] [Accepted: 11/04/2019] [Indexed: 01/28/2023]
Abstract
Static magnetic field (SMF) is gaining interest as a potential technique for modulating CNS neuronal activity. Previous studies have shown a pro-neurogenic effect of short periods of extremely low frequency pulsatile magnetic fields (PMF) in vivo and pro-survival effect of low intensity SMF in cultured neurons in vitro, but little is known about the in vivo effects of low to moderate intensity SMF on brain functions. We investigated the effect of continuously-applied SMF on subventricular zone (SVZ) neurogenesis and immature doublecortin (DCX)-expressing cells in the neocortex of young adult rats and in primary cultures of cortical neurons in vitro. A small (3 mm diameter) magnetic disc was implanted on the skull of rats at bregma, producing an average field strength of 4.3 mT at SVZ and 12.9 mT at inner neocortex. Levels of proliferation of SVZ stem cells were determined by 5-ethynyl-2'-deoxyuridine (EdU) labelling, and early neuronal phenotype development was determined by expression of doublecortin (DCX). To determine the effect of SMF on neurogenesis in vitro, permanent magnets were placed beneath the culture dishes. We found that low intensity SMF exposure enhances cell proliferation in SVZ and new DCX-expressing cells in neocortical regions of young adult rats. In primary cortical neuronal cultures, SMF exposure increased the expression of newly generated cells co-labelled with EdU and DCX or the mature neuronal marker NeuN, while activating a set of pro neuronal bHLH genes. SMF exposure has potential for treatment of neurodegenerative disease and conditions such as CNS trauma and affective disorders in which increased neurogenesis is desirable.
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33
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Rotheneichner P, Belles M, Benedetti B, König R, Dannehl D, Kreutzer C, Zaunmair P, Engelhardt M, Aigner L, Nacher J, Couillard-Despres S. Cellular Plasticity in the Adult Murine Piriform Cortex: Continuous Maturation of Dormant Precursors Into Excitatory Neurons. Cereb Cortex 2019; 28:2610-2621. [PMID: 29688272 PMCID: PMC5998952 DOI: 10.1093/cercor/bhy087] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Indexed: 11/14/2022] Open
Abstract
Neurogenesis in the healthy adult murine brain is based on proliferation and integration of stem/progenitor cells and is thought to be restricted to 2 neurogenic niches: the subventricular zone and the dentate gyrus. Intriguingly, cells expressing the immature neuronal marker doublecortin (DCX) and the polysialylated-neural cell adhesion molecule reside in layer II of the piriform cortex. Apparently, these cells progressively disappear along the course of ageing, while their fate and function remain unclear. Using DCX-CreERT2/Flox-EGFP transgenic mice, we demonstrate that these immature neurons located in the murine piriform cortex do not vanish in the course of aging, but progressively resume their maturation into glutamatergic (TBR1+, CaMKII+) neurons. We provide evidence for a putative functional integration of these newly differentiated neurons as indicated by the increase in perisomatic puncta expressing synaptic markers, the development of complex apical dendrites decorated with numerous spines and the appearance of an axonal initial segment. Since immature neurons found in layer II of the piriform cortex are generated prenatally and devoid of proliferative capacity in the postnatal cortex, the gradual maturation and integration of these cells outside of the canonical neurogenic niches implies that they represent a valuable, but nonrenewable reservoir for cortical plasticity.
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Affiliation(s)
- Peter Rotheneichner
- Institute of Experimental Neuroregeneration, Paracelsus Medical University, Salzburg, Austria.,Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), Paracelsus Medical University, Salzburg, Austria
| | - Maria Belles
- Neurobiology Unit, BIOTECMED, Universitat de València, Spanish Network for Mental Health Research CIBERSAM, INCLIVA, Valencia, Spain
| | - Bruno Benedetti
- Institute of Experimental Neuroregeneration, Paracelsus Medical University, Salzburg, Austria.,Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), Paracelsus Medical University, Salzburg, Austria
| | - Richard König
- Institute of Experimental Neuroregeneration, Paracelsus Medical University, Salzburg, Austria.,Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), Paracelsus Medical University, Salzburg, Austria.,Institute of Molecular Regenerative Medicine, Paracelsus Medical University, Salzburg, Austria
| | - Dominik Dannehl
- Institute of Experimental Neuroregeneration, Paracelsus Medical University, Salzburg, Austria.,Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), Paracelsus Medical University, Salzburg, Austria.,Institute of Neuroanatomy, Center for Biomedicine and Medical Technology (CBTM), Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Christina Kreutzer
- Institute of Experimental Neuroregeneration, Paracelsus Medical University, Salzburg, Austria.,Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), Paracelsus Medical University, Salzburg, Austria
| | - Pia Zaunmair
- Institute of Experimental Neuroregeneration, Paracelsus Medical University, Salzburg, Austria.,Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), Paracelsus Medical University, Salzburg, Austria
| | - Maren Engelhardt
- Institute of Neuroanatomy, Center for Biomedicine and Medical Technology (CBTM), Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Ludwig Aigner
- Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), Paracelsus Medical University, Salzburg, Austria.,Institute of Molecular Regenerative Medicine, Paracelsus Medical University, Salzburg, Austria
| | - Juan Nacher
- Neurobiology Unit, BIOTECMED, Universitat de València, Spanish Network for Mental Health Research CIBERSAM, INCLIVA, Valencia, Spain
| | - Sebastien Couillard-Despres
- Institute of Experimental Neuroregeneration, Paracelsus Medical University, Salzburg, Austria.,Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), Paracelsus Medical University, Salzburg, Austria
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34
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Kobro-Flatmoen A, Witter MP. Neuronal chemo-architecture of the entorhinal cortex: A comparative review. Eur J Neurosci 2019; 50:3627-3662. [PMID: 31293027 DOI: 10.1111/ejn.14511] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 06/18/2019] [Accepted: 06/27/2019] [Indexed: 11/29/2022]
Abstract
The identification of neuronal markers, that is, molecules selectively present in subsets of neurons, contributes to our understanding of brain areas and the networks within them. Specifically, recognizing the distribution of different neuronal markers facilitates the identification of borders between functionally distinct brain areas. Detailed knowledge about the localization and physiological significance of neuronal markers may also provide clues to generate new hypotheses concerning aspects of normal and abnormal brain functioning. Here, we provide a comprehensive review on the distribution within the entorhinal cortex of neuronal markers and the morphology of the neurons they reveal. Emphasis is on the comparative distribution of several markers, with a focus on, but not restricted to rodent, monkey and human data, allowing to infer connectional features, across species, associated with these markers, based on what is revealed by mainly rodent data. The overall conclusion from this review is that there is an emerging pattern in the distribution of neuronal markers in the entorhinal cortex when aligning data along a comparable coordinate system in various species.
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Affiliation(s)
- Asgeir Kobro-Flatmoen
- Kavli Institute for Systems Neuroscience, Centre for Neural Computation, Egil and Pauline Braathen and Fred Kavli Centre for Cortical Microcircuits, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Menno P Witter
- Kavli Institute for Systems Neuroscience, Centre for Neural Computation, Egil and Pauline Braathen and Fred Kavli Centre for Cortical Microcircuits, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
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35
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A balanced evaluation of the evidence for adult neurogenesis in humans: implication for neuropsychiatric disorders. Brain Struct Funct 2019; 224:2281-2295. [PMID: 31278571 DOI: 10.1007/s00429-019-01917-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Accepted: 06/25/2019] [Indexed: 12/17/2022]
Abstract
There is a widespread belief that neurogenesis exists in adult human brain, especially in the dentate gyrus, and it is to be maintained and, if possible, augmented with different stimuli including exercise and certain drugs. Here, we examine the evidence for adult human neurogenesis and note important limitations of the methodologies used to study it. A balanced review of the literature and evaluation of the data indicate that adult neurogenesis in human brain is improbable. In fact, in several high-quality recent studies in adult human brain, unlike in adult brains of other species, neurogenesis was not detectable. These findings suggest that the human brain requires a permanent set of neurons to maintain acquired knowledge for decades, which is essential for complex high cognitive functions unique to humans. Thus, stimulation and/or injection of neural stem cells into human brains may not only disrupt brain homeostatic systems, but also disturb normal neuronal circuits. We propose that the focus of research should be the preservation of brain neurons by prevention of damage, not replacement.
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36
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Sorrells SF, Paredes MF, Velmeshev D, Herranz-Pérez V, Sandoval K, Mayer S, Chang EF, Insausti R, Kriegstein AR, Rubenstein JL, Manuel Garcia-Verdugo J, Huang EJ, Alvarez-Buylla A. Immature excitatory neurons develop during adolescence in the human amygdala. Nat Commun 2019; 10:2748. [PMID: 31227709 PMCID: PMC6588589 DOI: 10.1038/s41467-019-10765-1] [Citation(s) in RCA: 81] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 04/18/2019] [Indexed: 02/07/2023] Open
Abstract
The human amygdala grows during childhood, and its abnormal development is linked to mood disorders. The primate amygdala contains a large population of immature neurons in the paralaminar nuclei (PL), suggesting protracted development and possibly neurogenesis. Here we studied human PL development from embryonic stages to adulthood. The PL develops next to the caudal ganglionic eminence, which generates inhibitory interneurons, yet most PL neurons express excitatory markers. In children, most PL cells are immature (DCX+PSA-NCAM+), and during adolescence many transition into mature (TBR1+VGLUT2+) neurons. Immature PL neurons persist into old age, yet local progenitor proliferation sharply decreases in infants. Using single nuclei RNA sequencing, we identify the transcriptional profile of immature excitatory neurons in the human amygdala between 4-15 years. We conclude that the human PL contains excitatory neurons that remain immature for decades, a possible substrate for persistent plasticity at the interface of the hippocampus and amygdala.
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Affiliation(s)
- Shawn F Sorrells
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA, 94143, USA
- Department of Neurological Surgery, University of California, San Francisco, San Francisco, CA, 94143, USA
| | - Mercedes F Paredes
- Department of Neurology, University of California, San Francisco, San Francisco, CA, 94143, USA
| | - Dmitry Velmeshev
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA, 94143, USA
| | - Vicente Herranz-Pérez
- Laboratory of Comparative Neurobiology, Institute Cavanilles, University of Valencia, CIBERNED, 46980, Valencia, Spain
- Predepartamental Unit of Medicine, Faculty of Health Sciences, Universitat Jaume I, 12071, Castelló de la Plana, Spain
| | - Kadellyn Sandoval
- Department of Neurology, University of California, San Francisco, San Francisco, CA, 94143, USA
| | - Simone Mayer
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA, 94143, USA
| | - Edward F Chang
- Department of Neurological Surgery, University of California, San Francisco, San Francisco, CA, 94143, USA
| | - Ricardo Insausti
- Human Neuroanatomy Laboratory, School of Medicine and CRIB, University of Castilla-La Mancha, 02006, Albacete, Spain
| | - Arnold R Kriegstein
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA, 94143, USA
| | - John L Rubenstein
- Department of Psychiatry, Rock Hall, University of California, San Francisco, San Francisco, CA, 94158-2324, USA
| | - Jose Manuel Garcia-Verdugo
- Laboratory of Comparative Neurobiology, Institute Cavanilles, University of Valencia, CIBERNED, 46980, Valencia, Spain
| | - Eric J Huang
- Department of Pathology, University of California, San Francisco, San Francisco, CA, 94143, USA
| | - Arturo Alvarez-Buylla
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA, 94143, USA.
- Department of Neurological Surgery, University of California, San Francisco, San Francisco, CA, 94143, USA.
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La Rosa C, Ghibaudi M, Bonfanti L. Newly Generated and Non-Newly Generated "Immature" Neurons in the Mammalian Brain: A Possible Reservoir of Young Cells to Prevent Brain Aging and Disease? J Clin Med 2019; 8:jcm8050685. [PMID: 31096632 PMCID: PMC6571946 DOI: 10.3390/jcm8050685] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 05/10/2019] [Accepted: 05/13/2019] [Indexed: 01/21/2023] Open
Abstract
Brain plasticity is important for translational purposes since most neurological disorders and brain aging problems remain substantially incurable. In the mammalian nervous system, neurons are mostly not renewed throughout life and cannot be replaced. In humans, the increasing life expectancy explains the increase in brain health problems, also producing heavy social and economic burden. An exception to the “static” brain is represented by stem cell niches leading to the production of new neurons. Such adult neurogenesis is dramatically reduced from fish to mammals, and in large-brained mammals with respect to rodents. Some examples of neurogenesis occurring outside the neurogenic niches have been reported, yet these new neurons actually do not integrate in the mature nervous tissue. Non-newly generated, “immature” neurons (nng-INs) are also present: Prenatally generated cells continuing to express molecules of immaturity (mostly shared with the newly born neurons). Of interest, nng-INs seem to show an inverse phylogenetic trend across mammals, being abundant in higher-order brain regions not served by neurogenesis and providing structural plasticity in rather stable areas. Both newly generated and nng-INs represent a potential reservoir of young cells (a “brain reserve”) that might be exploited for preventing the damage of aging and/or delay the onset/reduce the impact of neurological disorders.
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Affiliation(s)
- Chiara La Rosa
- Neuroscience Institute Cavalieri Ottolenghi (NICO), 10043 Orbassano, Italy.
- Department of Veterinary Sciences, University of Turin, 10095 Torino, Italy.
| | - Marco Ghibaudi
- Neuroscience Institute Cavalieri Ottolenghi (NICO), 10043 Orbassano, Italy.
| | - Luca Bonfanti
- Neuroscience Institute Cavalieri Ottolenghi (NICO), 10043 Orbassano, Italy.
- Department of Veterinary Sciences, University of Turin, 10095 Torino, Italy.
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Lack of MeCP2 leads to region-specific increase of doublecortin in the olfactory system. Brain Struct Funct 2019; 224:1647-1658. [PMID: 30923887 DOI: 10.1007/s00429-019-01860-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Accepted: 03/09/2019] [Indexed: 10/27/2022]
Abstract
The protein doublecortin is mainly expressed in migrating neuroblasts and immature neurons. The X-linked gene MECP2, associated to several neurodevelopmental disorders such as Rett syndrome, encodes the protein methyl-CpG-binding protein 2 (MeCP2), a regulatory protein that has been implicated in neuronal maturation and refinement of olfactory circuits. Here, we explored doublecortin immunoreactivity in the brain of young adult female Mecp2-heterozygous and male Mecp2-null mice and their wild-type littermates. The distribution of doublecortin-immunoreactive somata in neurogenic brain regions was consistent with previous reports in rodents, and no qualitative differences were found between genotypes or sexes. Quantitatively, we found a significant increase in doublecortin cell density in the piriform cortex of Mecp2-null males as compared to WT littermates. A similar increase was seen in a newly identified population of doublecortin cells in the olfactory tubercle. In these olfactory structures, however, the percentage of doublecortin immature neurons that also expressed NeuN was not different between genotypes. By contrast, we found no significant differences between genotypes in doublecortin immunoreactivity in the olfactory bulbs. Nonetheless, in the periglomerular layer of Mecp2-null males, we observed a specific decrease of immature neurons co-expressing doublecortin and NeuN. Overall, no differences were evident between Mecp2-heterozygous and WT females. In addition, no differences could be detected between genotypes in the density of doublecortin-immunoreactive cells in the hippocampus or striatum of either males or females. Our results suggest that MeCP2 is involved in neuronal maturation in a region-dependent manner.
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La Rosa C, Bonfanti L. Brain Plasticity in Mammals: An Example for the Role of Comparative Medicine in the Neurosciences. Front Vet Sci 2018; 5:274. [PMID: 30443551 PMCID: PMC6221904 DOI: 10.3389/fvets.2018.00274] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 10/15/2018] [Indexed: 12/11/2022] Open
Abstract
Comparative medicine deals with similarities and differences between veterinary and human medicine. All mammals share most basic cellular and molecular mechanisms, thus justifying murine animal models in a translational perspective; yet “mice are not men,” thus some biases can emerge when complex biological processes are concerned. Brain plasticity is a cutting-edge, expanding topic in the field of Neurosciences with important translational implications, yet, with remarkable differences among mammals, as emerging from comparative studies. In particular, adult neurogenesis (the genesis of new neurons from brain stem cell niches) is a life-long process in laboratory rodents but a vestigial, mostly postnatal remnant in humans and dolphins. Another form of “whole cell” plasticity consisting of a population of “immature” neurons which are generated prenatally but continue to express markers of immaturity during adulthood has gained interest more recently, as a reservoir of young neurons in the adult brain. The distribution of the immature neurons also seems quite heterogeneous among different animal species, being confined within the paleocortex in rodents while extending into neocortex in other mammals. A recent study carried out in sheep, definitely showed that gyrencephalic, large-sized brains do host higher amounts of immature neurons, also involving subcortical, white, and gray matter regions. Hence, “whole cell” plasticity such as adult neurogenesis and immature neurons are biological processes which, as a whole, cannot be studied exclusively in laboratory rodents, but require investigation in comparative medicine, involving large-sized, long-living mammals, in order to gain insights for translational purposes.
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Affiliation(s)
- Chiara La Rosa
- Neuroscience Institute Cavalieri Ottolenghi, Turin, Italy.,Department of Veterinary Sciences, University of Turin, Turin, Italy
| | - Luca Bonfanti
- Neuroscience Institute Cavalieri Ottolenghi, Turin, Italy.,Department of Veterinary Sciences, University of Turin, Turin, Italy
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40
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Parolisi R, Cozzi B, Bonfanti L. Humans and Dolphins: Decline and Fall of Adult Neurogenesis. Front Neurosci 2018; 12:497. [PMID: 30079011 PMCID: PMC6062615 DOI: 10.3389/fnins.2018.00497] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 07/02/2018] [Indexed: 02/06/2023] Open
Abstract
Pre-clinical research is carried out on animal models, mostly laboratory rodents, with the ultimate aim of translating the acquired knowledge to humans. In the last decades, adult neurogenesis (AN) has been intensively studied since it is viewed as a tool for fostering brain plasticity, possibly repair. Yet, occurrence, location, and rate of AN vary among mammals: the capability for constitutive neuronal production is substantially reduced when comparing small-brained, short living (laboratory rodents) and large-brained, long-living species (humans, dolphins). Several difficulties concerning scarce availability of fresh tissues, technical limits and ethical concerns did contribute in delaying and diverting the achievement of the picture of neurogenic plasticity in large-brained mammals. Some reports appeared in the last few years, starting to shed more light on this issue. Despite technical limits, data from recent studies mostly converge to indicate that neurogenesis is vestigial, or possibly absent, in regions of the adult human brain where in rodents neuronal addition continues into adult life. Analyses carried out in dolphins, mammals devoid of olfaction, but descendant of ancestors provided with olfaction, has shown disappearance of neurogenesis in both neonatal and adult individuals. Heterogeneity in mammalian structural plasticity remains largely underestimated by scientists focusing their research in rodents. Comparative studies are the key to understand the function of AN and the possible translational significance of neuronal replacement in humans. Here, we summarize comparative studies on AN and discuss the evolutionary implications of variations on the recruitment of new neurons in different regions and different species.
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Affiliation(s)
- Roberta Parolisi
- NICO - Neuroscience Institute Cavalieri Ottolenghi, Turin, Italy
| | - Bruno Cozzi
- Department of Comparative Biomedicine and Food Science, University of Padua, Padua, Italy
| | - Luca Bonfanti
- NICO - Neuroscience Institute Cavalieri Ottolenghi, Turin, Italy.,Department of Veterinary Sciences, University of Turin, Turin, Italy
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41
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La Rosa C, Parolisi R, Palazzo O, Lévy F, Meurisse M, Bonfanti L. Clusters of DCX+ cells "trapped" in the subcortical white matter of early postnatal Cetartiodactyla (Tursiops truncatus, Stenella coeruloalba and Ovis aries). Brain Struct Funct 2018; 223:3613-3632. [PMID: 29980931 DOI: 10.1007/s00429-018-1708-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Accepted: 07/02/2018] [Indexed: 01/08/2023]
Abstract
The cytoskeletal protein doublecortin (DCX) is a marker for neuronal cells retaining high potential for structural plasticity, originating from both embryonic and adult neurogenic processes. Some of these cells have been described in the subcortical white matter of neonatal and postnatal mammals. In mice and humans it has been shown they are young neurons migrating through the white matter after birth, reaching the cortex in a sort of protracted neurogenesis. Here we show that DCX+ cells in the white matter of neonatal and young Cetartiodactyla (dolphin and sheep) form large clusters which are not newly generated (in sheep, and likely neither in dolphins) and do not reach the cortical layers, rather appearing "trapped" in the white matter tissue. No direct contact or continuity can be observed between the subventricular zone region and the DCX+ clusters, thus indicating their independence from any neurogenic source (in dolphins further confirmed by the recent demonstration that periventricular neurogenesis is inactive since birth). Cetartiodactyla include two orders of large-brained, relatively long-living mammals (cetaceans and artiodactyls) which were recognized as two separate monophyletic clades until recently, yet, despite the evident morphological distinctions, they are monophyletic in origin. The brain of Cetartiodactyla is characterized by an advanced stage of development at birth, a feature that might explain the occurrence of "static" cell clusters confined within their white matter. These results further confirm the existence of high heterogeneity in the occurrence, distribution and types of structural plasticity among mammals, supporting the emerging view that multiple populations of DCX+, non-newly generated cells can be abundant in large-brained, long-living species.
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Affiliation(s)
- Chiara La Rosa
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano, Italy.,Department of Veterinary Sciences, University of Turin, Largo Braccini 2, 10095, Grugliasco, TO, Italy
| | - Roberta Parolisi
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano, Italy
| | - Ottavia Palazzo
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano, Italy
| | - Frederic Lévy
- UMR INRA, CNRS/Universitè F. Rabelais, IFCE Physiologie de la Reproduction et des Comportements, Nouzilly, France
| | - Maryse Meurisse
- UMR INRA, CNRS/Universitè F. Rabelais, IFCE Physiologie de la Reproduction et des Comportements, Nouzilly, France
| | - Luca Bonfanti
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano, Italy. .,Department of Veterinary Sciences, University of Turin, Largo Braccini 2, 10095, Grugliasco, TO, Italy.
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O'Farrell RA, Foley AG, Buggy DJ, Gallagher HC. Neurotoxicity of Inhalation Anesthetics in the Neonatal Rat Brain: Effects on Behavior and Neurodegeneration in the Piriform Cortex. Anesthesiol Res Pract 2018; 2018:6376090. [PMID: 30018637 PMCID: PMC6029509 DOI: 10.1155/2018/6376090] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 05/08/2018] [Indexed: 11/17/2022] Open
Abstract
There is concern that clinical use of anesthetic drugs may cause neurotoxicity in the developing brain and subsequent abnormal neurobehavior. We therefore evaluated neurotoxic effects of inhalation anesthetics in the neonatal rat brain, using in vivo histological and neurobehavioral outcomes. Wistar rats (n=79, postnatal day 15) were subjected to a clinically relevant single exposure of urethane, isoflurane, sevoflurane, or placebo, without surgery. At 48 h and 96 h, behavioral parameters were recorded and the animals were sacrificed. In cryosectioned brains, total cells and dying cells in layer II of the piriform cortex were counted using unbiased stereology. At 48 h, cell numbers in layer II of the piriform cortex of all drug-treated animals were reduced versus controls (p=0.01). The effect persisted at 96 h in isoflurane- and urethane-exposed animals. Piriform cortical layer II neurons undergoing degeneration, detected histologically by pyknotic nuclei and eosinophilic cytoplasm, were increased in the animals treated with isoflurane (1.9 ± 0.7 at 96 h) and urethane (2.4 ± 0.8 at 96 h) versus sevoflurane (0.8 ± 0.3 at 96 h) and controls (0.9 ± 0.2 at 96 h). Sevoflurane- and isoflurane-treated animals exhibited increased activity and decreased suckling compared with controls, and sevoflurane-exposed animals also displayed increased rearing behavior at both timepoints.
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Affiliation(s)
- Rachel A. O'Farrell
- Department of Anaesthesia, Mater Misericordiae University Hospital, Eccles Street, Dublin 7, Ireland
- School of Medicine, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
- Bon Secours Hospital, Glasnevin, Dublin 9, Ireland
| | - Andrew G. Foley
- Berand Neuropharmacology, NovaUCD, University College Dublin, Belfield Innovation Park, Dublin 4, Ireland
| | - Donal J. Buggy
- Department of Anaesthesia, Mater Misericordiae University Hospital, Eccles Street, Dublin 7, Ireland
- School of Medicine, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
- Outcomes Research Consortium, Cleveland Clinic, Cleveland, OH, USA
| | - Helen C. Gallagher
- School of Medicine, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
- UCD-Mater Clinical Research Centre, Eccles Street, Dublin 7, Ireland
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Neurochemical Characterization of PSA-NCAM + Cells in the Human Brain and Phenotypic Quantification in Alzheimer’s Disease Entorhinal Cortex. Neuroscience 2018; 372:289-303. [DOI: 10.1016/j.neuroscience.2017.12.019] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 11/22/2017] [Accepted: 12/15/2017] [Indexed: 01/07/2023]
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44
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Palazzo O, La Rosa C, Piumatti M, Bonfanti L. Do large brains of long-living mammals prefer non-newly generated, immature neurons? Neural Regen Res 2018; 13:633-634. [PMID: 29722307 PMCID: PMC5950665 DOI: 10.4103/1673-5374.230282] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Affiliation(s)
- Ottavia Palazzo
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano, Italy; Institute of Zoology-Neurogenetics, Universität Regensburg, Regensburg, Germany
| | - Chiara La Rosa
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano; Department of Veterinary Sciences, University of Turin, Grugliasco (TO), Italy
| | - Matteo Piumatti
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano, Italy; Université Libre de Bruxelles (ULB), Institute for Interdisciplinary Research in Human Biology (IRIBHM), Brussels, Belgium
| | - Luca Bonfanti
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano; Department of Veterinary Sciences, University of Turin, Grugliasco (TO), Italy
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45
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Non-Newly Generated, "Immature" Neurons in the Sheep Brain Are Not Restricted to Cerebral Cortex. J Neurosci 2017; 38:826-842. [PMID: 29217680 DOI: 10.1523/jneurosci.1781-17.2017] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 10/24/2017] [Accepted: 11/16/2017] [Indexed: 12/15/2022] Open
Abstract
A newly proposed form of brain structural plasticity consists of non-newly generated, "immature" neurons of the adult cerebral cortex. Similar to newly generated neurons, these cells express the cytoskeletal protein Doublecortin (DCX), yet they are generated prenatally and then remain in a state of immaturity for long periods. In rodents, the immature neurons are restricted to the paleocortex, whereas in other mammals, they are also found in neocortex. Here, we analyzed the DCX-expressing cells in the whole sheep brain of both sexes to search for an indicator of structural plasticity at a cellular level in a relatively large-brained, long-living mammal. Brains from adult and newborn sheep (injected with BrdU and analyzed at different survival times) were processed for DCX, cell proliferation markers (Ki-67, BrdU), pallial/subpallial developmental origin (Tbr1, Sp8), and neuronal/glial antigens for phenotype characterization. We found immature-like neurons in the whole sheep cortex and in large populations of DCX-expressing cells within the external capsule and the surrounding gray matter (claustrum and amygdala). BrdU and Ki-67 detection at neonatal and adult ages showed that all of these DCX+ cells were generated during embryogenesis, not after birth. These results show that the adult sheep, unlike rodents, is largely endowed with non-newly generated neurons retaining immature features, suggesting that such plasticity might be particularly important in large-brained, long-living mammals.SIGNIFICANCE STATEMENT Brain plasticity is important in adaptation and brain repair. Structural changes span from synaptic plasticity to adult neurogenesis, the latter being highly reduced in large-brained, long-living mammals (e.g., humans). The cerebral cortex contains "immature" neurons, which are generated prenatally and then remain in an undifferentiated state for long periods, being detectable with markers of immaturity. We studied the distribution and developmental origin of these cells in the whole brain of sheep, relatively large-brained, long-living mammals. In addition to the expected cortical location, we also found populations of non-newly generated neurons in several subcortical regions (external capsule, claustrum, and amygdala). These results suggests that non-neurogenic, parenchymal structural plasticity might be more important in large mammals with respect to adult neurogenesis.
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Parolisi R, Cozzi B, Bonfanti L. Non-neurogenic SVZ-like niche in dolphins, mammals devoid of olfaction. Brain Struct Funct 2017; 222:2625-2639. [PMID: 28238073 DOI: 10.1007/s00429-016-1361-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 12/22/2016] [Indexed: 11/29/2022]
Abstract
Adult neurogenesis has been implicated in brain plasticity and brain repair. In mammals, it is mostly restricted to specific brain regions and specific physiological functions. The function and evolutionary history of mammalian adult neurogenesis has been elusive so far. The largest neurogenic site in mammals (subventricular zone, SVZ) generates neurons destined to populate the olfactory bulb. The SVZ neurogenic activity appears to be related to the dependence of the species on olfaction since it occurs at high rates throughout life in animals strongly dependent on this function for their survival. Indeed, it dramatically decreases in humans, who do not depend so much on it. This study investigates whether the SVZ neurogenic site exists in mammals devoid of olfaction and olfactory brain structures, such as dolphins. Our results demonstate that a small SVZ-like region persists in these aquatic mammals. However, this region seems to have lost its neurogenic capabilities since neonatal stages. In addition, instead of the typical newly generated neuroblasts, some mature neurons were observed in the dolphin SVZ. Since cetaceans evolved from terrestrial ancestors, non-neurogenic SVZ may indicate extinction of adult neurogenesis in the absence of olfactory function, with the retention of an SVZ-like anatomical region either vestigial or of still unknown role.
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Affiliation(s)
- Roberta Parolisi
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano, Italy.,Department of Veterinary Sciences, University of Turin, Via Leonardo da Vinci, 44, 10095, Grugliasco, TO, Italy
| | - Bruno Cozzi
- Department of Comparative Biomedicine and Food Science, University of Padua, Legnaro, Italy
| | - Luca Bonfanti
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano, Italy. .,Department of Veterinary Sciences, University of Turin, Via Leonardo da Vinci, 44, 10095, Grugliasco, TO, Italy.
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47
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Chawana R, Patzke N, Alagaili AN, Bennett NC, Mohammed OB, Kaswera-Kyamakya C, Gilissen E, Ihunwo AO, Pettigrew JD, Manger PR. The Distribution of Ki-67 and Doublecortin Immunopositive Cells in the Brains of Three Microchiropteran Species, Hipposideros fuliginosus, Triaenops persicus, and Asellia tridens. Anat Rec (Hoboken) 2016; 299:1548-1560. [PMID: 27532288 DOI: 10.1002/ar.23460] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Revised: 05/24/2016] [Accepted: 06/09/2016] [Indexed: 01/26/2023]
Abstract
This study uses Ki-67 and doublecortin (DCX) immunohistochemistry to delineate potential neurogenic zones, migratory pathways, and terminal fields associated with adult neurogenesis in the brains of three microchiropterans. As with most mammals studied to date, the canonical subgranular and subventricular neurogenic zones were observed. Distinct labeling of newly born cells and immature neurons within the dentate gyrus of the hippocampus was observed in all species. A distinct rostral migratory stream (RMS) that appears to split around the medial aspect of the caudate nucleus was observed. These two rostral stream divisions appear to merge at the rostroventral corner of the caudate nucleus to turn and enter the olfactory bulb, where a large terminal field of immature neurons was observed. DCX immunolabeled neurons were observed mostly in the rostral neocortex, but a potential migratory stream to the neocortex was not identified. A broad swathe of newly born cells and immature neurons was found between the caudoventral division of the RMS and the piriform cortex. In addition, occasional immature neurons were observed in the amygdala and DCX-immunopositive axons were observed in the anterior commissure. While the majority of these features have been found in several mammal species, the large number of DCX immunolabeled cells found between the RMS and the piriform cortex and the presence of DCX immunostained axons in the anterior commissure are features only observed in microchiropterans and insectivores to date. In the diphyletic scenario of chiropteran evolution, these observations align the microchiropterans with the insectivores. Anat Rec, 299:1548-1560, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Richard Chawana
- School of Anatomical Sciences Faculty of Health Sciences, University of the Witwatersrand, 7 York Road, Parktown, 2193, Johannesburg, Republic of South Africa
| | - Nina Patzke
- School of Anatomical Sciences Faculty of Health Sciences, University of the Witwatersrand, 7 York Road, Parktown, 2193, Johannesburg, Republic of South Africa
| | - Abdulaziz N Alagaili
- KSU Mammals Research Chair, Department, of Zoology, College of Science, King Saud University, Box, 2455, Riyadh, 11451, Saudi Arabia.,Saudi Wildlife Authority, Riyadh, 11575, Saudi Arabia
| | - Nigel C Bennett
- KSU Mammals Research Chair, Department, of Zoology, College of Science, King Saud University, Box, 2455, Riyadh, 11451, Saudi Arabia.,Department of Zoology and Entomology, University of Pretoria, Pretoria, 0002, South Africa
| | - Osama B Mohammed
- KSU Mammals Research Chair, Department, of Zoology, College of Science, King Saud University, Box, 2455, Riyadh, 11451, Saudi Arabia
| | | | - Emmanuel Gilissen
- Department of African Zoology, Royal Museum for Central Africa, Leuvensesteenweg 13, B-3080, Tervuren, Belgium.,Laboratory of Histology and Neuropathology, Université Libre de Bruxelles, Brussels, 1070, Belgium.,Department of Anthropology, University of Arkansas, Fayetteville, Arkansas
| | - Amadi O Ihunwo
- School of Anatomical Sciences Faculty of Health Sciences, University of the Witwatersrand, 7 York Road, Parktown, 2193, Johannesburg, Republic of South Africa
| | - John D Pettigrew
- Queensland Brain Institute, University of Queensland, 4072, St. Lucia, Australia
| | - Paul R Manger
- School of Anatomical Sciences Faculty of Health Sciences, University of the Witwatersrand, 7 York Road, Parktown, 2193, Johannesburg, Republic of South Africa.
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Lipp HP, Bonfanti L. Adult Neurogenesis in Mammals: Variations and Confusions. BRAIN, BEHAVIOR AND EVOLUTION 2016; 87:205-221. [DOI: 10.1159/000446905] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Mammalian adult neurogenesis has remained enigmatic. Two lines of research have emerged. One focuses on a potential repair mechanism in the human brain. The other aims at elucidating its functional role in the hippocampal formation, chiefly in cognitive processes; however, thus far it has been unsuccessful. Here, we try to recognize the sources of errors and conceptual confusion in comparative studies and neurobehavioral approaches with a focus on mice. Evolutionarily, mammalian adult neurogenesis appears as protracted juvenile neurogenesis originating from precursor cells in the secondary proliferation zones, from where newly formed cells migrate to target regions in the forebrain. This late developmental process is downregulated differentially in various brain structures depending on species and age. Adult neurogenesis declines substantially during early adulthood and persists at low levels into senescence. Short-lasting episodes in proliferation or reduction of adult neurogenesis may reflect a multitude of factors, and have been studied chiefly in mice and rats. Comparative studies face both species-specific variations in staining and technical abilities of laboratories, lacking quantification of important reference measures (e.g. granule cell number) and evaluation of maturational markers whose persistence might be functionally more relevant than proliferation rates. Likewise, the confusion about the functional role of variations in adult hippocampal neurogenesis has many causes. Prominent is an inferential statistical approach, usually with low statistical power. Interpretation is complicated by multiple theories about hippocampal function, often unrealistically extrapolating from humans to rodents. We believe that the field of mammalian adult neurogenesis needs more critical thinking, more sophisticated hypotheses, better statistical, technical and behavioral approaches, and a broader conceptual perspective incorporating comparative aspects rather than neglecting them.
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Murray HC, Low VF, Swanson ME, Dieriks BV, Turner C, Faull RL, Curtis MA. Distribution of PSA-NCAM in normal, Alzheimer’s and Parkinson’s disease human brain. Neuroscience 2016; 330:359-75. [DOI: 10.1016/j.neuroscience.2016.06.003] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 06/01/2016] [Accepted: 06/02/2016] [Indexed: 12/25/2022]
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50
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Distribution and fate of DCX/PSA-NCAM expressing cells in the adult mammalian cortex: A local reservoir for adult cortical neuroplasticity? ACTA ACUST UNITED AC 2016. [DOI: 10.1007/s11515-016-1403-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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