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The Biological Behaviors of Neural Stem Cell Affected by Microenvironment from Host Organotypic Brain Slices under Different Conditions. Int J Mol Sci 2023; 24:ijms24044182. [PMID: 36835592 PMCID: PMC9964775 DOI: 10.3390/ijms24044182] [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: 01/10/2023] [Revised: 02/14/2023] [Accepted: 02/17/2023] [Indexed: 02/22/2023] Open
Abstract
Therapeutic strategies based on neural stem cells (NSCs) transplantation bring new hope for neural degenerative disorders, while the biological behaviors of NSCs after being grafted that were affected by the host tissue are still largely unknown. In this study, we engrafted NSCs that were isolated from a rat embryonic cerebral cortex onto organotypic brain slices to examine the interaction between grafts and the host tissue both in normal and pathological conditions, including oxygen-glucose deprivation (OGD) and traumatic injury. Our data showed that the survival and differentiation of NSCs were strongly influenced by the microenvironment of the host tissue. Enhanced neuronal differentiation was observed in normal conditions, while significantly more glial differentiation was observed in injured brain slices. The process growth of grafted NSCs was guided by the cytoarchitecture of host brain slices and showed the distinct difference between the cerebral cortex, corpus callosum and striatum. These findings provided a powerful resource for unraveling how the host environment determines the fate of grafted NSCs, and raise the prospect of NSCs transplantation therapy for neurological diseases.
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2
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Liu LR, Wang YX, He L, Xu YX, Huang JY, Peng TT, Yang XB, Pan J, Tang HM, Xu KS. Constraint-Induced Movement Therapy Promotes Neural Remodeling and Functional Reorganization by Overcoming Nogo-A/NgR/RhoA/ROCK Signals in Hemiplegic Cerebral Palsy Mice. Neurorehabil Neural Repair 2021; 35:145-157. [PMID: 33410385 DOI: 10.1177/1545968320981962] [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] [Indexed: 11/17/2022]
Abstract
Background. Little is known about the induction of functional and brain structural reorganization in hemiplegic cerebral palsy (HCP) by constraint-induced movement therapy (CIMT). Objective. We aimed to explore the specific molecular mechanism of functional and structural plasticity related to CIMT in HCP. Methods. The mice were divided into a control group and HCP groups with different interventions (unconstraint-induced movement therapy [UNCIMT], CIMT or siRNA-Nogo-A [SN] treatment): the HCP, HCP+UNCIMT, HCP+CIMT, HCP+SN, and HCP+SN+CIMT groups. Rotarod and front-limb suspension tests, immunohistochemistry, Golgi-Cox staining, transmission electron microscopy, and Western blot analyses were applied to measure motor function, neurons and neurofilament density, dendrites/axon areas, myelin integrity, and Nogo-A/NgR/RhoA/ROCK expression in the motor cortex. Results. The mice in the HCP+CIMT group had better motor function, greater neurons and neurofilament density, dendrites/axon areas, myelin integrity, and lower Nogo-A/NgR/RhoA/ROCK expression in the motor cortex than the HCP and HCP+UNCIMT groups (P < .05). Moreover, the expression of Nogo-A/NgR/RhoA/ROCK, the improvement of neural remodeling and motor function of mice in the HCP+SN group were similar to those in the HCP+CIMT group (P > .05). The neural remodeling and motor function of the HCP+SN+CIMT group were significantly greater than those in the HCP+SN and HCP+CIMT groups (P < .05). Motor function were positively correlated with the density of neurons (r = 0.450 and 0.309, respectively; P < .05) and neurofilament (r = 0.717 and 0.567, respectively; P < .05). Conclusions. CIMT might promote the remodeling of neurons, neurofilament, dendrites/axon areas, and myelin in the motor cortex by partially inhibiting the Nogo-A/NgR/RhoA/ROCK pathway, thereby promoting the improvement of motor function in HCP mice.
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Affiliation(s)
- Li-Ru Liu
- Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Yu-Xin Wang
- Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Lu He
- Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Yun-Xian Xu
- Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Jing-Yu Huang
- Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Ting-Ting Peng
- Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Xu-Bo Yang
- Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Jing Pan
- Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Hong-Mei Tang
- Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Kai-Shou Xu
- Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
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Nestin Selectively Facilitates the Phosphorylation of the Lissencephaly-Linked Protein Doublecortin (DCX) by cdk5/p35 to Regulate Growth Cone Morphology and Sema3a Sensitivity in Developing Neurons. J Neurosci 2020; 40:3720-3740. [PMID: 32273484 DOI: 10.1523/jneurosci.2471-19.2020] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 02/24/2020] [Accepted: 03/24/2020] [Indexed: 11/21/2022] Open
Abstract
Nestin, an intermediate filament protein widely used as a marker of neural progenitors, was recently found to be expressed transiently in developing cortical neurons in culture and in developing mouse cortex. In young cortical cultures, nestin regulates axonal growth cone morphology. In addition, nestin, which is known to bind the neuronal cdk5/p35 kinase, affects responses to axon guidance cues upstream of cdk5, specifically, to Sema3a. Changes in growth cone morphology require rearrangements of cytoskeletal networks, and changes in microtubules and actin filaments are well studied. In contrast, the roles of intermediate filament proteins in this process are poorly understood, even in cultured neurons. Here, we investigate the molecular mechanism by which nestin affects growth cone morphology and Sema3a sensitivity. We find that nestin selectively facilitates the phosphorylation of the lissencephaly-linked protein doublecortin (DCX) by cdk5/p35, but the phosphorylation of other cdk5 substrates is not affected by nestin. We uncover that this substrate selectivity is based on the ability of nestin to interact with DCX, but not with other cdk5 substrates. Nestin thus creates a selective scaffold for DCX with activated cdk5/p35. Last, we use cortical cultures derived from Dcx KO mice to show that the effects of nestin on growth cone morphology and on Sema3a sensitivity are DCX-dependent, thus suggesting a functional role for the DCX-nestin complex in neurons. We propose that nestin changes growth cone behavior by regulating the intracellular kinase signaling environment in developing neurons. The sex of animal subjects is unknown.SIGNIFICANCE STATEMENT Nestin, an intermediate filament protein highly expressed in neural progenitors, was recently identified in developing neurons where it regulates growth cone morphology and responsiveness to the guidance cue Sema3a. Changes in growth cone morphology require rearrangements of cytoskeletal networks, but the roles of intermediate filaments in this process are poorly understood. We now report that nestin selectively facilitates phosphorylation of the lissencephaly-linked doublecortin (DCX) by cdk5/p35, but the phosphorylation of other cdk5 substrates is not affected. This substrate selectivity is based on preferential scaffolding of DCX, cdk5, and p35 by nestin. Additionally, we demonstrate a functional role for the DCX-nestin complex in neurons. We propose that nestin changes growth cone behavior by regulating intracellular kinase signaling in developing neurons.
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Xing ZK, Zhang LQ, Zhang Y, Sun X, Sun XL, Yu HL, Zheng YW, He ZX, Zhu XJ. DIP2B Interacts With α-Tubulin to Regulate Axon Outgrowth. Front Cell Neurosci 2020; 14:29. [PMID: 32153366 PMCID: PMC7045754 DOI: 10.3389/fncel.2020.00029] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 01/31/2020] [Indexed: 01/14/2023] Open
Abstract
Axonal development is essential to the establishment of neuronal morphology and circuitry, although the mechanisms underlying axonal outgrowth during the early developmental stages remain unclear. Here, we showed that the conserved disco-interacting protein B (DIP2B) which consists of a DMAP1 domain and a crotonobetaine/carnitine CoA ligase (Caic) domain, is highly expressed in the excitatory neurons of the hippocampus. DIP2B knockout led to excessive axonal outgrowth but not polarity at an early developmental stage. Furthermore, the loss of DIP2B inhibited synaptic transmission for both spontaneous and rapid release in cultured hippocampal neurons. Interestingly, DIP2B function during axonal outgrowth requires tubulin acetylation. These findings reveal a new conserved regulator of neuronal morphology and provide a novel intervention mechanism for neurocognitive disorders.
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Affiliation(s)
- Zhen-Kai Xing
- Key Laboratory of Molecular Epigenetics Ministry of Education, Institute of Genetics and Cytology, Northeast Normal University, Changchun, China
| | - Lu-Qing Zhang
- Key Laboratory of Molecular Epigenetics Ministry of Education, Institute of Genetics and Cytology, Northeast Normal University, Changchun, China
| | - Yu Zhang
- Key Laboratory of Molecular Epigenetics Ministry of Education, Institute of Genetics and Cytology, Northeast Normal University, Changchun, China
| | - Xue Sun
- Key Laboratory of Molecular Epigenetics Ministry of Education, Institute of Genetics and Cytology, Northeast Normal University, Changchun, China
| | - Xiao-Lin Sun
- Key Laboratory of Molecular Epigenetics Ministry of Education, Institute of Genetics and Cytology, Northeast Normal University, Changchun, China
| | - Hua-Li Yu
- Key Laboratory of Molecular Epigenetics Ministry of Education, Institute of Genetics and Cytology, Northeast Normal University, Changchun, China
| | - Yao-Wu Zheng
- Key Laboratory of Molecular Epigenetics Ministry of Education, Institute of Genetics and Cytology, Northeast Normal University, Changchun, China
| | - Zi-Xuan He
- Key Laboratory of Molecular Epigenetics Ministry of Education, Institute of Genetics and Cytology, Northeast Normal University, Changchun, China
| | - Xiao-Juan Zhu
- Key Laboratory of Molecular Epigenetics Ministry of Education, Institute of Genetics and Cytology, Northeast Normal University, Changchun, China
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5
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Glucagon-like peptide-1 suppresses neuroinflammation and improves neural structure. Pharmacol Res 2019; 152:104615. [PMID: 31881271 DOI: 10.1016/j.phrs.2019.104615] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 12/10/2019] [Accepted: 12/12/2019] [Indexed: 12/22/2022]
Abstract
Glucagon-like peptide-1 (GLP-1) is a hormone mainly secreted from enteroendocrine L cells. GLP-1 and its receptor are also expressed in the brain. GLP-1 signaling has pivotal roles in regulating neuroinflammation and memory function, but it is unclear how GLP-1 improves memory function by regulating neuroinflammation. Here, we demonstrated that GLP-1 enhances neural structure by inhibiting lipopolysaccharide (LPS)-induced inflammation in microglia with the effects of GLP-1 itself on neurons. Inflammatory secretions of BV-2 microglia by LPS aggravated mitochondrial function and cell survival, as well as neural structure in Neuro-2a neurons. In inflammatory condition, GLP-1 suppressed the secretion of tumor necrosis factor-alpha (TNF-α)-associated cytokines and chemokines in BV-2 microglia and ultimately enhanced neurite complexity (neurite length, number of neurites from soma, and secondary branches) in Neuro-2a neurons. We confirmed that GLP-1 improves neurite complexity, dendritic spine morphogenesis, and spine development in TNF-α-treated primary cortical neurons based on altered expression levels of the factors related to neurite growth and spine morphology. Given that our data that GLP-1 itself enhances neurite complexity and spine morphology in neurons, we suggest that GLP-1 has a therapeutic potential in central nervous system diseases.
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Luck R, Urban S, Karakatsani A, Harde E, Sambandan S, Nicholson L, Haverkamp S, Mann R, Martin-Villalba A, Schuman EM, Acker-Palmer A, Ruiz de Almodóvar C. VEGF/VEGFR2 signaling regulates hippocampal axon branching during development. eLife 2019; 8:49818. [PMID: 31868583 PMCID: PMC6927742 DOI: 10.7554/elife.49818] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 11/14/2019] [Indexed: 12/20/2022] Open
Abstract
Axon branching is crucial for proper formation of neuronal networks. Although originally identified as an angiogenic factor, VEGF also signals directly to neurons to regulate their development and function. Here we show that VEGF and its receptor VEGFR2 (also known as KDR or FLK1) are expressed in mouse hippocampal neurons during development, with VEGFR2 locally expressed in the CA3 region. Activation of VEGF/VEGFR2 signaling in isolated hippocampal neurons results in increased axon branching. Remarkably, inactivation of VEGFR2 also results in increased axon branching in vitro and in vivo. The increased CA3 axon branching is not productive as these axons are less mature and form less functional synapses with CA1 neurons. Mechanistically, while VEGF promotes the growth of formed branches without affecting filopodia formation, loss of VEGFR2 increases the number of filopodia and enhances the growth rate of new branches. Thus, a controlled VEGF/VEGFR2 signaling is required for proper CA3 hippocampal axon branching during mouse hippocampus development.
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Affiliation(s)
- Robert Luck
- Biochemistry Center (BZH), University of Heidelberg, Heidelberg, Germany.,European Center for Angioscience, Medicine Faculty Mannheim, Heidelberg University, Heidelberg, Germany.,Institute for Transfusion Medicine and Immunology, Medicine Faculty Mannheim, Heidelberg University, Heidelberg, Germany
| | - Severino Urban
- Biochemistry Center (BZH), University of Heidelberg, Heidelberg, Germany
| | - Andromachi Karakatsani
- Biochemistry Center (BZH), University of Heidelberg, Heidelberg, Germany.,European Center for Angioscience, Medicine Faculty Mannheim, Heidelberg University, Heidelberg, Germany.,Institute for Transfusion Medicine and Immunology, Medicine Faculty Mannheim, Heidelberg University, Heidelberg, Germany
| | - Eva Harde
- Institute of Cell Biology and Neuroscience, University of Frankfurt, Frankfurt am Main, Germany.,Neurovascular Interface group, Max Planck Institute for Brain Research, Frankfurt am Main, Germany.,Buchmann Institute for Molecular Life Sciences (BMLS), University of Frankfurt, Frankfurt am Main, Germany
| | - Sivakumar Sambandan
- Department of Synaptic Plasticity, Max Planck Institute for Brain Research, Frankfurt am Main, Germany
| | - LaShae Nicholson
- Institute of Cell Biology and Neuroscience, University of Frankfurt, Frankfurt am Main, Germany.,Neurovascular Interface group, Max Planck Institute for Brain Research, Frankfurt am Main, Germany.,Buchmann Institute for Molecular Life Sciences (BMLS), University of Frankfurt, Frankfurt am Main, Germany
| | - Silke Haverkamp
- Imaging Facility, Max Planck Institute for Brain Research, Frankfurt am Main, Germany
| | - Rebecca Mann
- Biochemistry Center (BZH), University of Heidelberg, Heidelberg, Germany
| | - Ana Martin-Villalba
- Department of Molecular Neurobiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Erin Margaret Schuman
- Department of Synaptic Plasticity, Max Planck Institute for Brain Research, Frankfurt am Main, Germany
| | - Amparo Acker-Palmer
- Institute of Cell Biology and Neuroscience, University of Frankfurt, Frankfurt am Main, Germany.,Neurovascular Interface group, Max Planck Institute for Brain Research, Frankfurt am Main, Germany.,Buchmann Institute for Molecular Life Sciences (BMLS), University of Frankfurt, Frankfurt am Main, Germany
| | - Carmen Ruiz de Almodóvar
- Biochemistry Center (BZH), University of Heidelberg, Heidelberg, Germany.,European Center for Angioscience, Medicine Faculty Mannheim, Heidelberg University, Heidelberg, Germany.,Institute for Transfusion Medicine and Immunology, Medicine Faculty Mannheim, Heidelberg University, Heidelberg, Germany
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7
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Su Y, Liu J, Yu B, Ba R, Zhao C. Brpf1 Haploinsufficiency Impairs Dendritic Arborization and Spine Formation, Leading to Cognitive Deficits. Front Cell Neurosci 2019; 13:249. [PMID: 31213987 PMCID: PMC6558182 DOI: 10.3389/fncel.2019.00249] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 05/17/2019] [Indexed: 12/14/2022] Open
Abstract
Haploinsufficiency of the bromodomain and PHD finger-containing protein 1 (BRPF1) gene causes intellectual disability (ID), which is characterized by impaired intellectual and cognitive function; however, the neurological basis for ID and the neurological function of BRPF1 dosage in the brain remain unclear. Here, by crossing Emx1-cre mice with Brpf1fl/fl mice, we generated Brpf1 heterozygous mice to model BRPF1-related ID. Brpf1 heterozygotes showed reduced dendritic complexity in both hippocampal granule cells and cortical pyramidal neurons, accompanied by reduced spine density and altered spine and synapse morphology. An in vitro study of Brpf1 haploinsufficiency also demonstrated decreased frequency and amplitude of miniature EPSCs that may subsequently contribute to abnormal behaviors, including decreased anxiety levels and defective learning and memory. Our results demonstrate a critical role for Brpf1 dosage in neuron dendrite arborization, spine morphogenesis and behavior and provide insight into the pathogenesis of BRPF1-related ID.
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Affiliation(s)
- Yan Su
- Key Laboratory of Developmental Genes and Human Diseases, Ministry of Education, School of Medicine, Southeast University, Nanjing, China
| | - Junhua Liu
- Key Laboratory of Developmental Genes and Human Diseases, Ministry of Education, School of Medicine, Southeast University, Nanjing, China
| | - Baocong Yu
- Key Laboratory of Developmental Genes and Human Diseases, Ministry of Education, School of Medicine, Southeast University, Nanjing, China
| | - Ru Ba
- Key Laboratory of Developmental Genes and Human Diseases, Ministry of Education, School of Medicine, Southeast University, Nanjing, China
| | - Chunjie Zhao
- Key Laboratory of Developmental Genes and Human Diseases, Ministry of Education, School of Medicine, Southeast University, Nanjing, China
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8
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Bott CJ, Johnson CG, Yap CC, Dwyer ND, Litwa KA, Winckler B. Nestin in immature embryonic neurons affects axon growth cone morphology and Semaphorin3a sensitivity. Mol Biol Cell 2019; 30:1214-1229. [PMID: 30840538 PMCID: PMC6724523 DOI: 10.1091/mbc.e18-06-0361] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 02/21/2019] [Accepted: 02/26/2019] [Indexed: 12/14/2022] Open
Abstract
Correct wiring in the neocortex requires that responses to an individual guidance cue vary among neurons in the same location, and within the same neuron over time. Nestin is an atypical intermediate filament expressed strongly in neural progenitors and is thus used widely as a progenitor marker. Here we show a subpopulation of embryonic cortical neurons that transiently express nestin in their axons. Nestin expression is thus not restricted to neural progenitors, but persists for 2-3 d at lower levels in newborn neurons. We found that nestin-expressing neurons have smaller growth cones, suggesting that nestin affects cytoskeletal dynamics. Nestin, unlike other intermediate filament subtypes, regulates cdk5 kinase by binding the cdk5 activator p35. Cdk5 activity is induced by the repulsive guidance cue Semaphorin3a (Sema3a), leading to axonal growth cone collapse in vitro. Therefore, we tested whether nestin-expressing neurons showed altered responses to Sema3a. We find that nestin-expressing newborn neurons are more sensitive to Sema3a in a roscovitine-sensitive manner, whereas nestin knockdown results in lowered sensitivity to Sema3a. We propose that nestin functions in immature neurons to modulate cdk5 downstream of the Sema3a response. Thus, the transient expression of nestin could allow temporal and/or spatial modulation of a neuron's response to Sema3a, particularly during early axon guidance.
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Affiliation(s)
- C. J. Bott
- Department of Cell Biology, University of Virginia, Charlottesville, VA 22908
| | - C. G. Johnson
- Department of Anatomy and Cell Biology, Brody School of Medicine, East Carolina University, Greenville, NC 27834
| | - C. C. Yap
- Department of Cell Biology, University of Virginia, Charlottesville, VA 22908
| | - N. D. Dwyer
- Department of Cell Biology, University of Virginia, Charlottesville, VA 22908
| | - K. A. Litwa
- Department of Anatomy and Cell Biology, Brody School of Medicine, East Carolina University, Greenville, NC 27834
| | - B. Winckler
- Department of Cell Biology, University of Virginia, Charlottesville, VA 22908
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9
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Luo J, Liu Y, Nässel DR. Transcriptional Reorganization of Drosophila Motor Neurons and Their Muscular Junctions toward a Neuroendocrine Phenotype by the bHLH Protein Dimmed. Front Mol Neurosci 2017; 10:260. [PMID: 28855860 PMCID: PMC5557793 DOI: 10.3389/fnmol.2017.00260] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 07/31/2017] [Indexed: 01/13/2023] Open
Abstract
Neuroendocrine cells store and secrete bulk amounts of neuropeptides, and display morphological and molecular characteristics distinct from neurons signaling with classical neurotransmitters. In Drosophila the transcription factor Dimmed (Dimm), is a prime organizer of neuroendocrine capacity in a majority of the peptidergic neurons. These neurons display large cell bodies and extensive axon terminations that commonly do not form regular synapses. We ask which molecular compartments of a neuron are affected by Dimm to generate these morphological features. Thus, we ectopically expressed Dimm in glutamatergic, Dimm-negative, motor neurons and analyzed their characteristics in the central nervous system and the neuromuscular junction. Ectopic Dimm results in motor neurons with enlarged cell bodies, diminished dendrites, larger axon terminations and boutons, as well as reduced expression of synaptic proteins both pre and post-synaptically. Furthermore, the neurons display diminished vesicular glutamate transporter, and signaling components known to sustain interactions between the developing axon termination and muscle, such as wingless and frizzled are down regulated. Ectopic co-expression of Dimm and the insulin receptor augments most of the above effects on the motor neurons. In summary, ectopic Dimm expression alters the glutamatergic motor neuron phenotype toward a neuroendocrine one, both pre- and post-synaptically. Thus, Dimm is a key organizer of both secretory capacity and morphological features characteristic of neuroendocrine cells, and this transcription factor affects also post-synaptic proteins.
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Affiliation(s)
- Jiangnan Luo
- Department of Zoology, Stockholm UniversityStockholm, Sweden
| | - Yiting Liu
- Department of Zoology, Stockholm UniversityStockholm, Sweden
| | - Dick R Nässel
- Department of Zoology, Stockholm UniversityStockholm, Sweden
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10
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Hao Y, Collins C. Intrinsic mechanisms for axon regeneration: insights from injured axons in Drosophila. Curr Opin Genet Dev 2017; 44:84-91. [PMID: 28232273 PMCID: PMC5447494 DOI: 10.1016/j.gde.2017.01.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Revised: 01/17/2017] [Accepted: 01/26/2017] [Indexed: 12/18/2022]
Abstract
Axonal damage and loss are common and negative consequences of neuronal injuries, and also occur in some neurodegenerative diseases. For neurons to have a chance to repair their connections, they need to survive the damage, initiate new axonal growth, and ultimately establish new synaptic connections. This review discusses how recent work in Drosophila models have informed our understanding of the cellular pathways used by neurons to respond to axonal injuries. Similarly to mammalian neurons, Drosophila neurons appear to be more limited in their capacity regrow (regenerate) damaged axons in the central nervous system, but can undergo axonal regeneration to varying extents in the peripheral nervous system. Conserved cellular pathways are activated by axonal injury via mechanisms that are specific to axons but not dendrites, and new unanticipated inhibitors of axon regeneration can be identified via genetic screening. These findings, made predominantly via genetic and live imaging methods in Drosophila, emphasize the utility of this model organism for the identification and study of basic cellular mechanisms used for neuronal repair.
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Affiliation(s)
- Yan Hao
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109-1048, USA
| | - Catherine Collins
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109-1048, USA.
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11
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Li LS, Lu YL, Nie J, Xu YY, Zhang W, Yang WJ, Gong QH, Lu YF, Lu Y, Shi JS. Dendrobium nobile Lindl alkaloid, a novel autophagy inducer, protects against axonal degeneration induced by Aβ 25-35 in hippocampus neurons in vitro. CNS Neurosci Ther 2017; 23:329-340. [PMID: 28261990 DOI: 10.1111/cns.12678] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 01/12/2017] [Accepted: 01/16/2017] [Indexed: 12/19/2022] Open
Abstract
AIMS Axonal degeneration is a pathological symbol in the early stage of Alzheimer's disease (AD), which can be triggered by amyloid-β (Aβ) peptide deposition. Growing evidence indicates that deficit of autophagy eventually leads to the axonal degeneration. Our previous studies have shown that Dendrobium nobile Lindl alkaloid (DNLA) had protective effect on neuron impairment in vivo and in vitro; however, the underlying mechanisms is still unclear. METHODS We exposed cultured hippocampus neurons to Aβ25-35 to investigate the effect of DNLA in vitro. Axonal degeneration was evaluated by immunofluorescence staining and MTT assay. Neurons overexpressing GFP-LC3B were used to measure the formation of autophagosome. Autophagosome-lysosome fusion, the lysosomal pH, and cathepsin activity were assessed to reflect autophagy process. Proteins of interest were analyzed by Western blot. RESULTS DNLA pretreatment significantly inhibited axonal degeneration induced by Aβ25-35 peptide in vitro. Further studies revealed DNLA treatment increased autophagic flux through promoting formation and degradation of autophagosome in hippocampus neurons. Moreover, enhancement of autophagic flux was responsible for the protective effects of DNLA on axonal degeneration. CONCLUSIONS DNLA prevents Aβ25-35 -induced axonal degeneration via activation of autophagy process and could be a novel therapeutic target.
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Affiliation(s)
- Li-Sheng Li
- Department of Chemistry, Basic Medical Faculty, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Department of Pharmacology, Key Lab of Basic Pharmacology of Education Ministry, Zunyi Medical University, Zunyi, Guizhou, China
| | - Yan-Liu Lu
- Department of Pharmacology, Key Lab of Basic Pharmacology of Education Ministry, Zunyi Medical University, Zunyi, Guizhou, China
| | - Jing Nie
- Department of Pharmacology, Key Lab of Basic Pharmacology of Education Ministry, Zunyi Medical University, Zunyi, Guizhou, China
| | - Yun-Yan Xu
- Department of Pharmacology, Key Lab of Basic Pharmacology of Education Ministry, Zunyi Medical University, Zunyi, Guizhou, China
| | - Wei Zhang
- Department of Pharmacology, Key Lab of Basic Pharmacology of Education Ministry, Zunyi Medical University, Zunyi, Guizhou, China
| | - Wen-Jin Yang
- Department of Pharmacology, Key Lab of Basic Pharmacology of Education Ministry, Zunyi Medical University, Zunyi, Guizhou, China
| | - Qi-Hai Gong
- Department of Pharmacology, Key Lab of Basic Pharmacology of Education Ministry, Zunyi Medical University, Zunyi, Guizhou, China
| | - Yuan-Fu Lu
- Department of Pharmacology, Key Lab of Basic Pharmacology of Education Ministry, Zunyi Medical University, Zunyi, Guizhou, China
| | - Yang Lu
- Department of Chemistry, Basic Medical Faculty, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jing-Shan Shi
- Department of Pharmacology, Key Lab of Basic Pharmacology of Education Ministry, Zunyi Medical University, Zunyi, Guizhou, China
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12
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Ho MS. Neurodevelopment and degeneration. Neurosci Bull 2014; 30:539-41. [PMID: 25082533 DOI: 10.1007/s12264-014-1455-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Affiliation(s)
- Margaret S Ho
- Department of Anatomy and Neurobiology, School of Medicine, Tongji University, Shanghai, 200092, China,
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