Actin molecules promote neurite outgrowth of chick telencephalic neurons in vitro

The astroglial scar is a defining hallmark of secondary pathology following central nervous system (CNS) injury that, despite its role in limiting tissue damage, presents a significant barrier to neuroregeneration. Neural progenitor cell (NPC) therapies for tissue repair and regeneration have demonstrated favorable outcomes, the effects of which are ascribed not only to direct cell replacement but trophic support. Cytokines and growth factors secreted by NPCs aid in modifying the inhibitory and cytotoxic post-injury microenvironment. In an effort to harness and enhance the reparative potential of NPC secretome, we utilized the multifunctional and pro-regenerative cytokine, hepatocyte growth factor (HGF), as a cellular preconditioning agent. We first demonstrated the capacity of HGF to promote NPC survival in the presence of oxidative stress. We then assessed the capacity of this modified conditioned media (CM) to attenuate astrocyte reactivity and promote neurite outgrowth in vitro. HGF pre-conditioned NPCs demonstrated significantly increased levels of tissue inhibitor of metalloproteinases-1 and reduced vascular endothelial growth factor compared to untreated NPCs. In reactive astrocytes, HGF-enhanced NPC-CM effectively reduced glial fibrillary acidic protein (GFAP) expression and chondroitin sulfate proteoglycan deposition to a greater extent than either treatment alone, and enhanced neurite outgrowth of co-cultured neurons. in vivo, this combinatorial treatment strategy might enable tactical modification of the post-injury inhibitory astroglial environment to one that is more conducive to regeneration and functional recovery. These findings have important translational implications for the optimization of current cell-based therapies for CNS injury.

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Preferential outgrowth of central nervous system neurites on astrocytes and Schwann cells as compared with nonglial cells in vitro.

The Journal of Cell Biology ◽

10.1083/jcb.100.1.198 ◽

1985 ◽

Vol 100 (1) ◽

pp. 198-207 ◽

Cited By ~ 171

Author(s):

J R Fallon

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Neurite Outgrowth ◽

Schwann Cells ◽

Glial Cells ◽

Conditioned Media ◽

Cell Type ◽

Transmission Electron ◽

Promote Neurite Outgrowth

I have compared central nervous system (CNS) neurite outgrowth on glial and nonglial cells. Monolayers of glial cells (astrocytes and Schwann cells) or nonglial cells (e.g., fibroblasts) were prepared and were shown to be greater than 95% pure as judged by cell type-specific markers. These monolayers were then tested for their ability to support neurite outgrowth from various CNS explants. While CNS neurites grew vigorously on the glial cells, most showed little growth on nonglial cell monolayers. Neurites grew singly or in fine fascicles on the glial cells at rates greater than 0.5 mm/d. The neurite outgrowth on astrocytes was investigated in detail. Scanning and transmission electron microscopy showed that the neurites were closely apposed to the astrocyte surface and that the growth cones were well spread with long filopodia. There was no evidence of significant numbers of explant-derived cells migrating onto the monolayers. Two types of experiments indicated that factors associated with the astrocyte surface were primarily responsible for the vigorous neurite outgrowth seen on these cells: (a) Conditioned media from either astrocytes or fibroblasts had no effect on the pattern of outgrowth on fibroblasts and astrocytes, and conditioned media factors from either cell type did not promote neurite outgrowth when bound to polylysine-coated dishes. (b) When growing CNS neurites encountered a boundary between astrocytes and fibroblasts, they stayed on the astrocytes and did not encroach onto the fibroblasts. These experiments strongly suggest that molecules specific to the surfaces of astrocytes make these cells particularly attractive substrates for CNS neurite outgrowth, and they raise the possibility that similar molecules on embryonic glial cells may play a role in guiding axonal growth during normal CNS development.

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Adipose-derived stem cells differentiate into a Schwann cell phenotype and promote neurite outgrowth in vitro

Experimental Neurology ◽

10.1016/j.expneurol.2007.06.029 ◽

2007 ◽

Vol 207 (2) ◽

pp. 267-274 ◽

Cited By ~ 381

Author(s):

Paul J. Kingham ◽

Daniel F. Kalbermatten ◽

Daljeet Mahay ◽

Stephanie J. Armstrong ◽

Mikael Wiberg ◽

...

Keyword(s):

Stem Cells ◽

Schwann Cell ◽

Neurite Outgrowth ◽

Cell Phenotype ◽

Adipose Derived Stem Cells ◽

Promote Neurite Outgrowth

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Factors promoting axon growth in the deer antler

Animal Production Science ◽

10.1071/an10167 ◽

2011 ◽

Vol 51 (4) ◽

pp. 351 ◽

Cited By ~ 3

Author(s):

M. Nieto-Diaz ◽

W. Pita-Thomas ◽

R. M. Maza ◽

M. Yunta-Gonzalez ◽

M. J. Lopez-Rodríguez ◽

...

Keyword(s):

Nerve Growth Factor ◽

Growth Factor ◽

Neurite Outgrowth ◽

Axon Growth ◽

Growth Promoters ◽

Serum Factors ◽

Nerve Growth ◽

Promote Neurite Outgrowth ◽

Neurotrophin 3

During their annual regeneration, antlers are innervated by trigeminal sensory axons growing at the highest rate recorded for any adult mammal. Previous analyses established the presence in the antler of nerve growth factor and neurotrophin 3 neurotrophins, which may underlie this rapid nerve growth. We are currently exploring the expression of other molecules that may be involved in such growth (axon growth promoters) combining several gene-expression techniques. Preliminary results indicate the expression of different growth promoters in the antler velvet, five of them not previously described in deer. The expression of these molecules as well as others described in the literature suggests that antler velvet promotes axon growth. However, most promoters expressed in the velvet are also present in unmodified deer skin. Thus, it must be asked why axons grow so fast in the antler? To answer that question, we developed a series of in vitro experiments using sensory neurons from adult and embryo rodents. These studies suggested that soluble proteins secreted by the velvet strongly promote neurite outgrowth. Using specific blocking antibodies, we demonstrated that nerve growth factor is partially responsible for these effects although other yet unidentified proteins seem also to be involved. The studies also showed that neither endocrine serum factors nor antler tissue substrate stimulate neurite outgrowth, although deep velvet layers cause neurite outgrowth orientation.

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Faculty Opinions recommendation of Overexpression of nerve growth factor in peritoneal fluid from women with endometriosis may promote neurite outgrowth in endometriotic lesions.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.6965956.7163054 ◽

2010 ◽

Author(s):

Warren Nothnick

Keyword(s):

Nerve Growth Factor ◽

Growth Factor ◽

Neurite Outgrowth ◽

Peritoneal Fluid ◽

Nerve Growth ◽

Promote Neurite Outgrowth

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Spastin Interacts with CRMP2 to Regulate Neurite Outgrowth by Controlling Microtubule Dynamics through Phosphorylation Modifications

CNS & Neurological Disorders - Drug Targets ◽

10.2174/1871527319666201026165855 ◽

2020 ◽

Vol 19 ◽

Author(s):

Sumei Li ◽

Jifeng Zhang ◽

Jiaqi Zhang ◽

Jiong Li ◽

Longfei Cheng ◽

...

Keyword(s):

Neurite Outgrowth ◽

Hippocampal Neurons ◽

Neuronal Development ◽

Phosphorylation Site ◽

Microtubule Dynamics ◽

Microtubule Assembly ◽

C Terminus ◽

Mediator Protein ◽

Branch Formation

Aims: Our work aims to revealing the underlying microtubule mechanism of neurites outgrowth during neuronal development, and also proposes a feasible intervention pathway for reconstructing neural network connections after nerve injury. Background: Microtubule polymerization and severing are the basis for the neurite outgrowth and branch formation. Collapsin response mediator protein 2 (CRMP2) regulates axonal growth and branching as a binding partner of the tubulin heterodimer to promote microtubule assembly. And spastin participates in the growth and regeneration of neurites by severing microtubules into small segments. However, how CRMP2 and spastin cooperate to regulate neurite outgrowth by controlling the microtubule dynamics needs to be elucidated. Objective: To explore whether neurite outgrowth was mediated by coordination of CRMP2 and spastin. Method: Hippocampal neurons were cultured in vitro in 24-well culture plates for 4 days before being used to perform the transfection. Calcium phosphate was used to transfect the CRMP2 and spastin constructs and their control into the neurons. An interaction between CRMP2 and spastin was examined by using pull down, CoIP and immunofluorescence colocalization assays. And immunostaining was also performed to determine the morphology of neurites. Result: We first demonstrated that CRMP2 interacted with spastin to promote the neurite outgrowth and branch formation. Furthermore, our results identified that phosphorylation modification failed to alter the binding affinities of CRMP2 for spastin, but inhibited their binding to microtubules. CRMP2 interacted with the MTBD domain of spastin via its C-terminus, and blocking the binding sites of them inhibited the outgrowth and branch formation of neurites. In addition, we confirmed one phosphorylation site S210 at spastin in hippocampal neurons and phosphorylation spastin at site S210 promoted the neurite outgrowth but not branch formation by remodeling microtubules. Conclusion: Taken together, our data demonstrated that the interaction of CRMP2 and spastin is required for neurite outgrowth and branch formation and their interaction is not regulated by their phosphorylation.

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A screened PirB antagonist peptide antagonizes Aβ42-mediated inhibition of neurite outgrowth in vitro

Applied Microbiology and Biotechnology ◽

10.1007/s00253-021-11363-2 ◽

2021 ◽

Author(s):

Zheng Zhang ◽

Zijian Wang ◽

Zhipeng Ling ◽

Yu Li ◽

Junping Pan ◽

...

Keyword(s):

Neurite Outgrowth

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Neurotoxicity of Seven MEIC Chemicals Evaluated in Organotypic Cultures of Chick Embryonic Dorsal Root Ganglia

Alternatives to Laboratory Animals ◽

10.1177/026119299702500311 ◽

1997 ◽

Vol 25 (3) ◽

pp. 303-309

Author(s):

Václav Mandys ◽

Katerina Jirsová ◽

Jirí Vrana

Keyword(s):

Toxic Effect ◽

Neurite Outgrowth ◽

Dorsal Root Ganglia ◽

Dorsal Root ◽

Growth Parameters ◽

In Vitro Cytotoxicity ◽

Organotypic Cultures ◽

Response Curves ◽

Agar Culture

The neurotoxic effects of seven selected Multicenter Evaluation of In Vitro Cytotoxicity programme chemicals (methanol, ethanol, isopropanol, sodium chloride, potassium chloride, iron [II] sulphate and chloroform) were evaluated in organotypic cultures of chick embryonic dorsal root ganglia (DRG), maintained in a soft agar culture medium. Two growth parameters of neurite outgrowth from the ganglia — the mean radial length of neurites and the area of neurite outgrowth — were used to evaluate the toxicities of the chemicals. Dose-dependent decreases of both parameters were observed in all experiments. IC50 values (the concentration causing 50% inhibition of growth) were calculated from the dose-response curves established at three time-points during culture, i.e. 24, 48 and 72 hours. The lowest toxic effect was observed in cultures exposed to methanol (the IC50 ranging from 580mM to 1020mM). The highest toxic effect was observed in cultures exposed to iron (II) sulphate (the IC50 ranging from 1.2mM to 1.7mM). The results of other recent experiments suggest that organotypic cultures of DRG can be used during in vitro studies on target organ toxicity within the peripheral nervous system. Moreover, these cultures preserve the internal organisation of the tissue, maintain intercellular contacts, and thus reflect the in vitro situation, more precisely than other cell cultures.

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