scholarly journals A Brief Review of In Vitro Models for Injury and Regeneration in the Peripheral Nervous System

2022 ◽  
Vol 23 (2) ◽  
pp. 816
Author(s):  
Parvathi Varier ◽  
Gayathri Raju ◽  
Pallavi Madhusudanan ◽  
Chinnu Jerard ◽  
Sahadev A. Shankarappa
Keyword(s):  
Nervous System ◽  
Peripheral Nervous System ◽  
Nerve Injury ◽  
Axonal Injury ◽  
In Vitro Models ◽  
Model Systems ◽  
Neural Regeneration ◽  
Post Injury

Nerve axonal injury and associated cellular mechanisms leading to peripheral nerve damage are important topics of research necessary for reducing disability and enhancing quality of life. Model systems that mimic the biological changes that occur during human nerve injury are crucial for the identification of cellular responses, screening of novel therapeutic molecules, and design of neural regeneration strategies. In addition to in vivo and mathematical models, in vitro axonal injury models provide a simple, robust, and reductionist platform to partially understand nerve injury pathogenesis and regeneration. In recent years, there have been several advances related to in vitro techniques that focus on the utilization of custom-fabricated cell culture chambers, microfluidic chamber systems, and injury techniques such as laser ablation and axonal stretching. These developments seem to reflect a gradual and natural progression towards understanding molecular and signaling events at an individual axon and neuronal-soma level. In this review, we attempt to categorize and discuss various in vitro models of injury relevant to the peripheral nervous system and highlight their strengths, weaknesses, and opportunities. Such models will help to recreate the post-injury microenvironment and aid in the development of therapeutic strategies that can accelerate nerve repair.

In Vitro Testing of Neurotoxicity

1990 ◽  
Vol 18 (1_part_1) ◽  
pp. 153-179
Author(s):  
Erik Walum ◽  
Elisabeth Hansson ◽  
Alan L. Harvey
Keyword(s):  
Nervous System ◽  
Ex Vivo ◽  
Cell Types ◽  
Biochemical Properties ◽  
In Vitro Models ◽  
Model Systems ◽  
Culture Methods ◽  
Developmental Potential

Many of the toxic compounds that are at large in the environment represent a risk to our neuronal functions. Chemicals may have a direct or indirect effect on the nervous system and they may interfere with general biochemical properties or specific neuronal structures and processes. In this review, a brief presentation of the major neurotoxicological targets is given, together with a discussion of some aspects of the use of different in vitro models for screening purposes and mechanistic studies. It is believed that in vitro methods offer special opportunities for the development of new neurotoxicological assays, and that this development will mainly involve cultured model systems. Therefore, a presentation of nerve and glia tissue culture methods is given, followed by an overview of how information on the action of mercury and mercurials, excitotoxins and acrylamide has been obtained through the use of cultured cell models. It is concluded that the developmental potential in cell neurotoxicology lies within the areas of separation and identification of cells representative for different structures in the nervous system, co-cultivation of different cell types, in vivo/in vitro (ex vivo) procedures, chemically defined media, metabolic competent cultures of human cells and improved physiological conditions for cultivation and exposure.

scholarly journals In Vitro Analysis of Transneuronal Spread of an Alphaherpesvirus Infection in Peripheral Nervous System Neurons

2007 ◽  
Vol 81 (13) ◽  
pp. 6846-6857 ◽  
Author(s):  
B. Feierbach ◽  
M. Bisher ◽  
J. Goodhouse ◽  
L. W. Enquist
Keyword(s):  
Nervous System ◽  
Peripheral Nervous System ◽  
Pseudorabies Virus ◽  
Viral Glycoprotein ◽  
In Vitro System ◽  
Vitro Analysis ◽  
In Vitro Analysis ◽  
Postsynaptic Target

ABSTRACT The neurotropic alphaherpesviruses invade and spread in the nervous system in a directional manner between synaptically connected neurons. Until now, this property has been studied only in living animals and has not been accessible to in vitro analysis. In this study, we describe an in vitro system in which cultured peripheral nervous system neurons are separated from their neuron targets by an isolator chamber ring. Using pseudorabies virus (PRV), an alphaherpesvirus capable of transneuronal spread in neural circuits of many animals, we have recapitulated in vitro all known genetic requirements for retrograde and anterograde transneuronal spread as determined previously in vivo. We show that in vitro transneuronal spread requires intact axons and the presence of the viral proteins gE, gI, and Us9. We also show that transneuronal spread is dependent on the viral glycoprotein gB, which is required for membrane fusion, but not on gD, which is required for extracellular spread. We demonstrate ultrastructural differences between anterograde- and retrograde-traveling virions. Finally, we show live imaging of dynamic fluorescent virion components in axons and postsynaptic target neurons.

scholarly journals Drug Penetration into the Central Nervous System: Pharmacokinetic Concepts and In Vitro Model Systems

Pharmaceutics ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1542
Author(s):  
Felix Neumaier ◽  
Boris D. Zlatopolskiy ◽  
Bernd Neumaier
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Model Systems ◽  
Pharmacokinetic Parameters ◽  
Special Focus ◽  
Drug Penetration ◽  
The Central Nervous System ◽  
The Brain

Delivery of most drugs into the central nervous system (CNS) is restricted by the blood–brain barrier (BBB), which remains a significant bottleneck for development of novel CNS-targeted therapeutics or molecular tracers for neuroimaging. Consistent failure to reliably predict drug efficiency based on single measures for the rate or extent of brain penetration has led to the emergence of a more holistic framework that integrates data from various in vivo, in situ and in vitro assays to obtain a comprehensive description of drug delivery to and distribution within the brain. Coupled with ongoing development of suitable in vitro BBB models, this integrated approach promises to reduce the incidence of costly late-stage failures in CNS drug development, and could help to overcome some of the technical, economic and ethical issues associated with in vivo studies in animal models. Here, we provide an overview of BBB structure and function in vivo, and a summary of the pharmacokinetic parameters that can be used to determine and predict the rate and extent of drug penetration into the brain. We also review different in vitro models with regard to their inherent shortcomings and potential usefulness for development of fast-acting drugs or neurotracers labeled with short-lived radionuclides. In this regard, a special focus has been set on those systems that are sufficiently well established to be used in laboratories without significant bioengineering expertise.

scholarly journals Non-Thermal Plasma Accelerates Astrocyte Regrowth and Neurite Regeneration Following Physical Trauma In Vitro

2019 ◽  
Vol 9 (18) ◽  
pp. 3747 ◽  
Author(s):  
Kritika S. Katiyar ◽  
Abraham Lin ◽  
Alexander Fridman ◽  
Carolyn E. Keating ◽  
D. Kacy Cullen ◽  
...  
Keyword(s):  
Nervous System ◽  
Thermal Plasma ◽  
Cell Types ◽  
Neural Regeneration ◽  
Mechanical Trauma ◽  
Post Injury ◽  
Physical Trauma ◽  
Non Thermal Plasma ◽  
Differentiation And Proliferation

Non-thermal plasma (NTP), defined as a partially ionized gas, is an emerging technology with several biomedical applications, including tissue regeneration. In particular, NTP treatment has been shown to activate endogenous biological processes to promote cell regrowth, differentiation, and proliferation in multiple cell types. However, the effects of this therapy on nervous system regeneration have not yet been established. Accordingly, the current study explored the effects of a nanosecond-pulsed dielectric barrier discharge plasma on neural regeneration. Following mechanical trauma in vitro, plasma was applied either directly to (1) astrocytes alone, (2) neurons alone, or (3) neurons or astrocytes in a non-contact co-culture. Remarkably, we identified NTP treatment intensities that accelerated both neurite regeneration and astrocyte regrowth. In astrocyte cultures alone, an exposure of 20–90 mJ accelerated astrocyte re-growth up to three days post-injury, while neurons required lower treatment intensities (≤20 mJ) to achieve sub-lethal outgrowth. Following injury to neurons in non-contact co-culture with astrocytes, 20 mJ exposure of plasma to only neurons or astrocytes resulted in increased neurite regeneration at three days post-treatment compared to the untreated, but no enhancement was observed when both cell types were treated. At day seven, although regeneration further increased, NTP did not elicit a significant increase from the control. However, plasma exposure at higher intensities was found to be injurious, underscoring the need to optimize exposure levels. These results suggest that growth-promoting physiological responses may be elicited via properly calibrated NTP treatment to neurons and/or astrocytes. This could be exploited to accelerate neurite re-growth and modulate neuron-astrocyte interactions, thereby hastening nervous system regeneration.

Demonstration of subpopulations with differing cancer stem cell phenotypes in xenograft and in vitro models of colorectal liver metastases.

2013 ◽  
Vol 31 (4_suppl) ◽  
pp. 394-394
Author(s):  
Dominic E. Sanford ◽  
Andrew Giorgi ◽  
Brian D. Goetz ◽  
Roheena Z. Panni ◽  
William G. Hawkins ◽  
...  
Keyword(s):  
Stem Cells ◽  
Cancer Stem Cells ◽  
Liver Metastases ◽  
In Vitro Models ◽  
Model Systems ◽  
Cell Populations ◽  
Tumor Initiating Cells ◽  
Distinct Cell

394 Background: Tumors are composed of heterogeneous cell populations, some of which demonstrate enhanced tumor-forming capabilities (so-called tumor initiating cells [TIC] or cancer stem cells). In colorectal cancer (CRC), CD133, 44, and 24 are cell surface markers that identify TIC. Therefore, we sought to determine if CRC liver metastases (CRC-LM) form xenografts (in vivo) and cell cultures (in vitro) with TIC markers. Methods: CRC-LM were grafted in NOD/SCID mice and passaged serially. Xenografts were mechanically dissociated and cultured under sphere forming conditions. Flow cytometry was performed for TIC phenotype. Results: 16 of 18 (89%) CRC-LM specimens formed tumors in mice. Xenografts formed EpCAM+ tumors and spheres. The frequency of CD133+, CD44+, and CD133+/CD44+ tumor cells were 55%, 33%, and 23%, respectively. There was a subpopulation of CD133+/CD44+ cells with elevated CD44 expression(CD44hi). This CD133+/CD44hi population was also CD24+; representing 5% of cells. Eight of eleven (73%) xenografts formed spheres in vitro. The frequency of CD133+, CD44+, and CD133+/CD44+ cells were 63%, 47%, and 26%, respectively. CD133+/CD44+/CD24+ cells made up 8% of sphere-forming cells. There was a non-significant trend towards increased frequency of CD133+, CD44+, and CD133/CD44 positive cells in the spheres compared to the xenografts. However, the percentage of CD133+/CD44+/CD24+ cells was significantly increased in spheres relative to xenografts (8% vs. 5%, respectively; p<0.05) (see Table). Conclusions: CRC-LM derived xenografts and spheres are composed of distinct cell populations with differing levels of TIC/cancer stem cells. Sphere cultures may enhance for the most enriched TIC population. Thus, xenografts and sphere cultures are important model systems to further study the importance of cancer stem cells in CRC progression and metastases. [Table: see text]

scholarly journals GAP-43 is expressed by nonmyelin-forming Schwann cells of the peripheral nervous system.

1992 ◽  
Vol 116 (6) ◽  
pp. 1455-1464 ◽  
Author(s):  
R Curtis ◽  
H J Stewart ◽  
S M Hall ◽  
G P Wilkin ◽  
R Mirsky ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Peripheral Nervous System ◽  
Schwann Cells ◽  
Glial Cells ◽  
Distal Stump ◽  
Metabolic Labeling ◽  
General Role

Recently it has been demonstrated that the growth-associated protein GAP-43 is not confined to neurons but is also expressed by certain central nervous system glial cells in tissue culture and in vivo. This study has extended these observations to the major class of glial cells in the peripheral nervous system, Schwann cells. Using immunohistochemical techniques, we show that GAP-43 immunoreactivity is present in Schwann cell precursors and in mature non-myelin-forming Schwann cells both in vitro and in vivo. This immunoreactivity is shown by Western blotting to be a membrane-associated protein that comigrates with purified central nervous system GAP-43. Furthermore, metabolic labeling experiments demonstrate definitively that Schwann cells in culture can synthesize GAP-43. Mature myelin-forming Schwann cells do not express GAP-43 but when Schwann cells are removed from axonal contact in vivo by nerve transection GAP-43 expression is upregulated in nearly all Schwann cells of the distal stump by 4 wk after denervation. In contrast, in cultured Schwann cells GAP-43 is not rapidly upregulated in cells that have been making myelin in vivo. Thus the regulation of GAP-43 appears to be complex and different from that of other proteins associated with nonmyelin-forming Schwann cells such as N-CAM, glial fibrillary acidic protein, A5E3, and nerve growth factor receptor, which are rapidly upregulated in myelin-forming cells after loss of axonal contact. These observations suggest that GAP-43 may play a more general role in the nervous system than previously supposed.

scholarly journals The Angiotensin II Type 2 Receptor, a Target for Protection and Regeneration of the Peripheral Nervous System?

2021 ◽  
Vol 14 (3) ◽  
pp. 175
Author(s):  
Aurore Danigo ◽  
Amandine Rovini ◽  
Flavien Bessaguet ◽  
Hichem Bouchenaki ◽  
Amandine Bernard ◽  
...  
Keyword(s):  
Nervous System ◽  
Angiotensin Ii ◽  
Peripheral Nervous System ◽  
Neuroprotective Effects ◽  
Pharmacological Studies ◽  
The Central Nervous System ◽  
G Protein Coupled

Preclinical evidence, accumulated over the past decade, indicates that the angiotensin II type 2 receptor (AT2R) stimulation exerts significant neuroprotective effects in various animal models of neuronal injury, notably in the central nervous system. While the atypical G protein-coupled receptor superfamily nature of AT2R and its related signaling are still under investigation, pharmacological studies have shown that stimulation of AT2R leads to neuritogenesis in vitro and in vivo. In this review, we focus on the potential neuroprotective and neuroregenerative roles of AT2R specifically in the peripheral nervous system (PNS). The first section describes the evidence for AT2R expression in the PNS and highlights current controversies concerning the cellular distribution of the receptor. The second section focuses on AT2R signaling implicated in neuronal survival and in neurite outgrowth. The following sections review the relatively few preclinical studies highlighting the putative neuroprotective and neuroregenerative effects of AT2R stimulation in the context of peripheral neuropathy.

scholarly journals Quantitative Proteomic Analysis of Mouse Sciatic Nerve Reveals Post-injury Upregulation of ADP-Dependent Glucokinase Promoting Macrophage Phagocytosis

2021 ◽  
Vol 14 ◽  
Author(s):  
Kai Zhang ◽  
Qingyao Wang ◽  
Yiyao Liang ◽  
Yu Yan ◽  
Haiqiong Wang ◽  
...  
Keyword(s):  
Sciatic Nerve ◽  
Nerve Injury ◽  
Proteomic Analysis ◽  
Inflammatory Responses ◽  
Post Injury ◽  
Injured Nerve ◽  
Protein Levels ◽  
Macrophage Phagocytosis

Nerve injury induces profound and complex changes at molecular and cellular levels, leading to axonal self-destruction as well as immune and inflammatory responses that may further promote neurodegeneration. To better understand how neural injury changes the proteome within the injured nerve, we set up a mouse model of sciatic nerve injury (SNI) and conducted an unbiased, quantitative proteomic study followed by biochemical assays to confirm some of the changed proteins. Among them, the protein levels of ADP-dependent glucokinase (ADPGK) were significantly increased in the injured sciatic nerve. Further examination indicated that ADPGK was specifically expressed and upregulated in macrophages but not neurons or Schwann cells upon injury. Furthermore, culturing immortalized bone marrow-derived macrophages (iBMDMs) in vitro with the conditioned media from transected axons of mouse dorsal root ganglion (DRG) neurons induced ADPGK upregulation in iBMDMs, suggesting that injured axons could promote ADPGK expression in macrophages non-cell autonomously. Finally, we showed that overexpression of ADPGK per se did not activate macrophages but promoted the phagocytotic activity of lipopolysaccharides (LPS)-treated macrophages. Together, this proteomic analysis reveals interesting changes of many proteins within the injured nerve and our data identify ADPGK as an important in vivo booster of injury-induced macrophage phagocytosis.

Sign in / Sign up

Export Citation Format

Share Document