Rozprawy doktorskie: „Cortical neuronal cultures”

1

Boulos, Sherif. "Identification and characterisation of potential neuroprotective proteins induced by erythropoietin (EPO) preconditioning of cortical neuronal cultures". University of Western Australia. School of Biomedical and Chemical Sciences, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0128.

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[Truncated abstract] Clinical therapeutic agents to directly inhibit ischaemic neuronal death are presently unavailable. One approach to developing therapeutics is based upon the identification of proteins up-regulated by 'preconditioning', a natural adaptive response utilised by the neural cells to counter damaging insults, such as ischaemia. Thus, my project aimed to firstly identify proteins differentially expressed following erythropoietin (EPO) mediated neuronal preconditioning and secondly to assess whether any of these proteins possessed neuroprotective activity using in vitro ischaemia like models. To achieve the first aim, it was shown that in vitro neuronal EPO preconditioning could: (i) induce cell signal changes in neuronal cultures, (ii) protect neurons against in vitro ischaemia and (iii) induce differential protein expression. Overall, 40 differentially expressed proteins were identified in cortical neuronal cultures following EPO preconditioning. In order to investigate the neuroprotective or neurodamaging activity of proteins induced by EPO preconditioning I developed an adenoviral expression system for use in neuronal cultures. To this end, I assessed the suitability of four promoters (cytomegalovirus [CMV], rous sarcoma virus [RSV], human synapsin 1 [hSYN1], rat synapsin 1 [rSYN1]) previously used to express proteins in neuronal cultures and demonstrated the superiority of the RSV promoter for this purpose. ... Finally, in order to validate this adenoviral expression system, I over-expressed the anti-apoptotic protein Bcl-XL in neuronal cultures and subsequently confirmed its neuroprotective activity in the in vitro ischaemia and oxidative stress models used in my project. Using this adenoviral vector system and the in vitro oxidative stress model I assessed a number of proteins up-regulated by EPO preconditioning. The results of this preliminary study indicated that cyclophilin A (CyPA), peroxiredoxin 2 (PRDX2) and superoxide dismutase 1 (SOD1) over-expression were neuroprotective. It was subsequently verified that adenoviral mediated over-expression of CyPA and PRDX2, v but not SOD1 in cortical neuronal cultures could protect neurons from in vitro ischaemia. I also confirmed that CyPA mRNA increased in the rat hippocampus in response to 3 minutes of global cerebral ischaemia. Interestingly, an increase in CyPA, PRDX2 or SOD1 protein was not observed in the same experimental paradigm. To investigate CyPA's mode of action I confirmed that cultured neurons, but not astrocytes, express the CyPA receptor, CD147. It was also demonstrated that administration of exogenous CyPA protein to neuronal cultures could protect neurons against oxidative and ischaemic injury. I further demonstrated that exogenous administration of CyPA induces a rapid and transient activation of the extracellular signal-regulated kinase (ERK) 1/2 pathway in neuronal cultures. From this observation, I have proposed that the extracellular mediated neuroprotective activity of CyPA occurs via CD147 receptor signalling and activation of ERK1/2 pro-survival pathways. Based on the findings reported in this thesis, the neuroprotective activities of PRDX2 and CyPA warrant further investigation as targets for the development of new therapies to treat cerebral ischaemia.

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2

Sattler, Rita. "Effects of moderate and profound hypothermia on excitatory amino acid-induced neuronal injury in cortical cell cultures". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1996. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ51597.pdf.

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3

Mohandas, Bhavna. "The Effect of Exogenous Nitric Oxide on Neuronal Zn ²⁺ Homeostasis". Ohio : Ohio University, 2005. http://www.ohiolink.edu/etd/view.cgi?ohiou1126041116.

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4

Wu, Calvin. "In Vitro Cortical Networks for Disease Modeling and Drug Evaluation". Thesis, University of North Texas, 2013. https://digital.library.unt.edu/ark:/67531/metadc407860/.

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In translational research, disease models in preclinical studies are used as media for discovery of drugs or novel therapeutics. Development of in vitro models for various neurological diseases that enable efficient pharmacological or toxicological screening has been ongoing but challenging. Recognizing the potential benefit of in vitro disease models, dysfunctions in the cortical neuronal networks were induced to mimic the functional pathology of neurological symptoms using microelectrode arrays. Two different disease states – tinnitusand excitotoxicity – were investigated and discussed. In this model, pentylenetetrazol-induced increase in spontaneous firing rate and synchrony in the auditory cortical networks was used as correlate of tinnitus. Potential tinnitus treatment drugs from several different classes – including the novel class of potassium channel openers – were screened and quantified. The potentialtherapeutic values of these drugs were also discussed as the basis for drug repurposing. Functional excitotoxicity was induced by cisplatin (a cancer drug that causes neurological sideeffects) and glutamate (the major excitatory neurotransmitter). As proof-of-principle that the model may contribute to expediting the development of therapeutics, cisplatin excitotoxicity wasprevented by the antioxidant D-methionine, while glutamate excitotoxicity was prevented by ceftriaxone (a modulator of a glutamate reuptake transporter). In the latter part of the study, with results linking two of the screened drugs L-carnitine and D-methionine to GABAA receptor activation, it was demonstrated that this model not only served as an efficient drug-screening platform, but can be utilized to functionally investigate the underlying mechanism of drugs. Inaddition, several practical or conceptual directions for future studies to improve on this in vitro disease model are suggested.

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Qin, Yan. "Studies of Zinc Transport and Its Contribution to Zinc Homeostasis in Cultured Cortical Neurons". View abstract, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:3339515.

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6

Honda, Kazuhiro. "Nongenomic antiapoptotic signal transduction by estrogen in cultured cortical neurons". Kyoto University, 2002. http://hdl.handle.net/2433/149665.

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Turina, Dean. "Propofol changes the cytoskeletal function in neurons : An experimental study in cortical cultures". Doctoral thesis, Linköpings universitet, Anestesiologi med intensivvård, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-77219.

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Every day, general anaesthetics are given to a large number of patients around the world but the cellular mechanisms of how anaesthetics act are still not clear. General anaesthetics cause the intended unconsciousness, amnesia and immobility in patients, but also side effects such as a decrease in mean arterial pressure and arrhythmia, both of which contribute to complications such as heart damage and stroke. With more knowledge of the mechanism of anaesthetic drugs, these complications could be reduced. It has been shown that anaesthetics cause a disruption of the thalamocortical connectivity and brain network connectivity. How the network communication is disrupted however is not known. Propofol and thiopental are both intravenous anaesthetic drugs used widely in clinical anaesthesia. They bind to the GABAA receptor and enhance its function. The cytoskeleton helps the cell to maintain its shape and participate in cellular movement and transport. Cellular transport to and from a neuron’s cell body and periphery is performed by motor proteins that move vesicles, organelles and proteins along cytoskeletal tracks. We have previously shown that propofol causes a reorganisation of the cytoskeleton protein actin in neurons, but we were further interested to study the effects of propofol and thiopental on the cytoskeletal function of cultured cortical rat neurons. Our results show that propofol and thiopental cause neurite (axon and dendrite) retraction. Propofol’s effects were time- and dose-dependent, and can be reversed when propofol is removed. We were able to inhibit propofolinduced neurite retraction if we stabilised actin by blocking either the motor protein myosin II or the GABAA receptor. We have previously shown that a small GTP-binding protein, RhoA, inhibits propofol-caused actin reorganisation. Propofol-induced neurite retraction was mediated via a downstream effector of RhoA, ROK, which induces phosphorylation of the myosin light chain and increases contractility. Furthermore, we have shown that propofol causes a switch from anterograde to retrograde transport and increases the average velocity of the moving vesicles in neurites. The propofol induced retrograde vesicle transport was GABAA receptor-mediated. Orexin A is a neuropeptide which regulates the sleep/awake cycle and has also been shown to reduce anaesthesia in animals when given intracerebroventricularly. We found that orexin A reverses propofol and thiopental-induced neurite retraction and actin reorganisation. Moreover, we have shown that the orexin A inhibition of propofol-induced neurite retraction is mediated via the PLD/PKC intracellular signalling pathway. Propofol and thiopental decreased the tyrosine phosphorilation of the intermediate cytoskeletal protein vimentin which is reversed by orexin A. Taken together, these results suggest that propofol causes a time- and dose-dependent, reversible and GABAAreceptor-mediated neurite retraction in cultured cortical rat neurons. Propofol also causes a switch from anterograde to retrograde vesicle transport in neurites. Orexin A reverses propofol and thiopental-induced neurite retraction and cytoskeletal reorganisation. Orexin A inhibits propofol-induced neurite retraction via the PLD/PKC intracellular signalling pathway.

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8

Durant, Stormy R. "In Vitro Exploration of Functional Acrolein Toxicity with Cortical Neuronal Networks". Thesis, University of North Texas, 2018. https://digital.library.unt.edu/ark:/67531/metadc1157516/.

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Acrolein is produced endogenously after traumatic brain injury (TBI) and is considered a primary mechanism for secondary damage occurring after TBI. We are using frontal cortex networks derived from mouse embryos and grown on microelectrode arrays in vitro to monitor the spontaneous activity of networks and the changes that occur after acrolein application. Networks exposed to acrolein exhibit a biphasic response profile. An initial increase in network activity, followed by a decrease to 100% activity loss in applications ≥ 50 µM. In applications below 50 µM, acrolein was not toxic but generated activity instability with coordinated but irregular population busts lasting for up to 6 days. The increase in activity preceding toxicity may be linked to a decrease in free spermine, a free radical scavenger that modulates Na+, K+, Ca+ channels as well as NMDA, Kainate, and AMPA receptors. Action potential wave shape analysis after 20 and 30 µM acrolein application revealed a concentration-dependent 15-33% increase in peak to peak amplitude within minutes after exposure. For the same concentrations of acrolein (50 µM), the time required to reach 100% activity loss (IT100) was longer in serum-free medium than in medium with 5% serum, in which IT100 values were reduced by a factor of 4. The greater toxicity in the presence of serum may be explained by acrolein adducts on serum proteins. These reaction products have been shown by other labs to be toxic in cell culture. This in vitro system could be used to expand biochemical analyses such as acrolein-induced spermine depletion and may provide an effective platform for investigating cell culture correlates of secondary TBI damage.

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9

Lavergne, Pauline, i Pauline Lavergne. "Caractérisation des réponses de neurones corticaux de rat en culture suite à des stimulations glutamatergiques grâce à la microscopie holographique numérique : vers une mesure de la balance excitation/inhibition". Master's thesis, Université Laval, 2020. http://hdl.handle.net/20.500.11794/38153.

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De nouvelles preuves suggèrent que les dysfonctionnements des circuits sous-jacents aux symptômes et aux déficits cognitifs des maladies psychiatriques pourraient être causés par une altération des paramètres d'équilibre d’excitation/inhibition (E/I). Cependant, les preuves physiologiques directes de cette hypothèse à partir de données électrophysiologiques et de neuro-imagerie non invasives sont jusqu'à présent rares. Pour apporter un soutien supplémentaire à l’hypothèse de l’équilibre E/I, la présente étude a appliqué une approche avancée de microscopie holographique numérique (MHN) pour examiner la dynamique des systèmes excitateurs/inhibiteurs suite à une stimulation glutamatergique dans des réseaux de neurones à différents stades de maturation neuronale. Cette approche fournissant une mesure approximative très précise des variations de mouvement de l’eau dans les cellules permet d’étudier certains processus physiologiques, tels que ceux reliés à l’activité neuronale. Cette étude a ainsi permis d’améliorer les connaissances sur la dynamique de la réponse neuronale induite par le glutamate, notamment en la caractérisant dans des cultures de neurones corticaux primaires de rats postnataux. L’activation des neurones engendrée par le glutamate, le principal neurotransmetteur excitateur, a révélé des changements plus ou moins persistants de la morphologie et des propriétés intracellulaires des neurones. De plus, les différentes réponses obtenues indiquent que le glutamate engendre des mécanismes d’activation et des processus de régulation du volume neuronal distincts d’un neurone à l’autre, probablement dépendant de l’état d’excitabilité de ce dernier qui résulte de l’interaction complexe des neurones inhibiteurs et excitateurs. Ainsi, la régulation de l’équilibre E/I de réseaux neuronaux pourrait potentiellement être reflétée par la proportion des différentes réponses de phase induites lors de stimulation de réseaux neuronaux au glutamate.
De nouvelles preuves suggèrent que les dysfonctionnements des circuits sous-jacents aux symptômes et aux déficits cognitifs des maladies psychiatriques pourraient être causés par une altération des paramètres d'équilibre d’excitation/inhibition (E/I). Cependant, les preuves physiologiques directes de cette hypothèse à partir de données électrophysiologiques et de neuro-imagerie non invasives sont jusqu'à présent rares. Pour apporter un soutien supplémentaire à l’hypothèse de l’équilibre E/I, la présente étude a appliqué une approche avancée de microscopie holographique numérique (MHN) pour examiner la dynamique des systèmes excitateurs/inhibiteurs suite à une stimulation glutamatergique dans des réseaux de neurones à différents stades de maturation neuronale. Cette approche fournissant une mesure approximative très précise des variations de mouvement de l’eau dans les cellules permet d’étudier certains processus physiologiques, tels que ceux reliés à l’activité neuronale. Cette étude a ainsi permis d’améliorer les connaissances sur la dynamique de la réponse neuronale induite par le glutamate, notamment en la caractérisant dans des cultures de neurones corticaux primaires de rats postnataux. L’activation des neurones engendrée par le glutamate, le principal neurotransmetteur excitateur, a révélé des changements plus ou moins persistants de la morphologie et des propriétés intracellulaires des neurones. De plus, les différentes réponses obtenues indiquent que le glutamate engendre des mécanismes d’activation et des processus de régulation du volume neuronal distincts d’un neurone à l’autre, probablement dépendant de l’état d’excitabilité de ce dernier qui résulte de l’interaction complexe des neurones inhibiteurs et excitateurs. Ainsi, la régulation de l’équilibre E/I de réseaux neuronaux pourrait potentiellement être reflétée par la proportion des différentes réponses de phase induites lors de stimulation de réseaux neuronaux au glutamate.
New evidences suggest that circuit dysfunctions underlying symptoms and cognitive deficits of psychiatric disorders may be caused by impaired excitation/inhibition equilibrium parameters (E/I). However, direct physiological evidences supporting this hypothesis from non-invasive electrophysiological and neuroimaging remain scarce. To provide additional support concerning the E/I balance hypothesis, this study uses an advanced digital holographic microscopy (DHM) approach to explore the dynamics of excitatory/inhibitory systems following glutamatergic stimulation in neural networks at different stages of neuronal maturation. This approach provides a very accurate approximate measurement of the water movement variations in cells allowing to study certain specific physiological processes, such as those related to neuronal activity. This study improves the knowledge regarding the dynamics of the glutamate-induced neuronal response, especially by characterizing it in cultures of primary cortical neurons of postnatal rats. The activation of neurons induced by glutamate, which is the main excitatory neurotransmitter, revealed more or less permanent changes in the morphology and intracellular properties of neurons. Moreover, the various responses obtained indicate that glutamate generates different neuronal activation mechanisms and neuronal volume regulation processes from a neuron to another, probably depending to the excitability state of the neuron that results from the complex interaction of inhibitory and excitatory neurons. Thus, the E/I balance regulation of neural networks could potentially be reflected by the proportion of different phase responses induced during glutamate neural network stimulation.
New evidences suggest that circuit dysfunctions underlying symptoms and cognitive deficits of psychiatric disorders may be caused by impaired excitation/inhibition equilibrium parameters (E/I). However, direct physiological evidences supporting this hypothesis from non-invasive electrophysiological and neuroimaging remain scarce. To provide additional support concerning the E/I balance hypothesis, this study uses an advanced digital holographic microscopy (DHM) approach to explore the dynamics of excitatory/inhibitory systems following glutamatergic stimulation in neural networks at different stages of neuronal maturation. This approach provides a very accurate approximate measurement of the water movement variations in cells allowing to study certain specific physiological processes, such as those related to neuronal activity. This study improves the knowledge regarding the dynamics of the glutamate-induced neuronal response, especially by characterizing it in cultures of primary cortical neurons of postnatal rats. The activation of neurons induced by glutamate, which is the main excitatory neurotransmitter, revealed more or less permanent changes in the morphology and intracellular properties of neurons. Moreover, the various responses obtained indicate that glutamate generates different neuronal activation mechanisms and neuronal volume regulation processes from a neuron to another, probably depending to the excitability state of the neuron that results from the complex interaction of inhibitory and excitatory neurons. Thus, the E/I balance regulation of neural networks could potentially be reflected by the proportion of different phase responses induced during glutamate neural network stimulation.

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10

Hetsch, Florian Jan Alexander [Verfasser]. "Induction of Synapses by Agrin in Cultured Cortical Neurons / Florian Jan Alexander Hetsch". Berlin : Freie Universität Berlin, 2015. http://d-nb.info/1072622262/34.

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Hetsch, Florian [Verfasser]. "Induction of Synapses by Agrin in Cultured Cortical Neurons / Florian Jan Alexander Hetsch". Berlin : Freie Universität Berlin, 2015. http://d-nb.info/1072622262/34.

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12

Thomas, Dustin G. "Zinc transport protein-1 (ZnT1) contributes to Zn2⁺ efflux in primary cultures of rat cortical neurons". Ohio : Ohio University, 2006. http://www.ohiolink.edu/etd/view.cgi?ohiou1163544193.

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Kaufman, Alexandra. "Opposing roles of synaptic and extrasynaptic NMDA receptor signaling in co-cultured striatal and cortical neurons". Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/36794.

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The N-methyl-d-aspartate receptor- type glutamate receptor (NMDAR) plays a unique and vital role in subcellular signaling. Ca²⁺ influx initiates signaling cascades important for synaptic plasticity and survival. However, overactivation of the receptor leads to toxicity and cell death. This dichotomy is partially explained by the subcellular location of the receptor. NMDARs located at the synapse have been shown to signal for cell survival, while extrasynaptic receptors signal for cell death. Thus far, the interplay between synaptic and extrasynaptic NMDARs has been studied exclusively in cortical (CTX) and hippocampal neurons; it is unknown whether medium spiny neurons of the striatum (MSNs), which bear the brunt of neurodegeneration in Huntington disease, follow the same pattern. There is evidence to suggest that signaling pathways may be different in CTX compared with MSNs. Here we study, for the first time, synaptic versus extrasynaptic signaling in striatal MSNs, focusing on activation of cAMP response element binding protein (CREB). Synaptic NMDARs activate CREB in striatal MSNs, although this pathway is slightly less efficacious compared with CTX. Similarly to CTX, extrasynaptic NMDARs shut off CREB in MSNs. MSNs are less susceptible to NMDA-mediated toxicity compared with CTX. Blocking extrasynaptic receptors with memantine (30 µM) and GluN2B-containing receptors with ifenprodil (3 µM) prevents CREB shutoff and rescues neurons from NMDA-mediated toxicity. This work may provide cell- and NMDAR subtype-specific targets for treatment of diseases with putative NMDAR involvement, including neurodegenerative diseases and ischemia.

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Geci, Catherine. "Induction of somatostatin by -amyloid peptide and the neuroprotective effect of somatostatin in cultured cortical neurons". Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=32994.

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Somatostatin (SST) is a member of a multi-gene family of peptides with two bioactive products, SST-14 and SST-28, that are synthesized in the brain and in peripheral tissues such as the pancreas and the gut. SST modulates neurotransmission, and acts as a inhibitory regulator of cell secretion and proliferation. These actions are mediated by a family of G protein coupled receptors with five distinct receptor subtypes termed SSTR1-5. Another putative role of SST is the neuroprotective action it exhibits in in vitro models of neurodegeneration.
To determine whether SST extends its alleged neuroprotective role to other models of neurotoxicity, we have characterized the effect of another potent neurotoxin, beta-amyeloid peptide (Abeta)25--35, on SST production in primary rat cortical neuronal cultures.
Furthermore, we attempted to determine the mechanism through which SST mediates its neuroprotective effect against Abeta-induced toxicity by using SSTR-subtype selective analogs as well as SSTR antisense oligonucleotides. Cell viability was assayed after treatment with SSTR agonists and Abeta 40muM for 24 hours. (Abstract shortened by UMI.)

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15

Yang, Benson P. (Benson Pin-Sheng). "Regulation of Tau gene expression by Aβ and the amyloid precursosr protein in cultured cortical neurons". Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/44497.

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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1997.
Includes bibliographical references (leaves 44-52).
by Benson P. Yang.
M.Eng.

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16

Mayaudon, Jean-Marie. "Nanostructuration de polymères d'implants neuronaux flexibles, caractérisation de leur biocompatibilité par une étude in-vitro, et conception d'un câble flexible pour l'enregistrement cortical de haute densité". Thesis, Université Grenoble Alpes, 2020. http://www.theses.fr/2020GRALS001.

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La recherche en réhabilitation des fonctions motrices ou en exploration du cerveau par l’utilisation des neuroprothèses a deux enjeux majeurs adressés dans cette thèse : les implants doivent être de haute biocompatibilité sur le long terme et avec une haute densité d’électrodes. La littérature révèle que la nanostructuration de surface peut améliorer l’adhésion et le réseau des neurites de neurones et que les implants fins et souples, composés des polymères SU-8, polyimide ou parylène, réduisent la cicatrice gliale. Cette thèse montre qu’une gravure plasma (argon, oxygène) forme des nanofils (NFs) verticaux de SU-8 de diamètre 50 à 100 nm et longs jusqu’à 8 µm. Des NFs peuvent être transposés à un implant fait de fils SU8 de diamètre 10 µm. Aussi, le dépôt d’or (10 nm) suivi de la gravure plasma mène à des NFs verticaux de même diamètre et longs jusqu’à 4,2 µm pour le polyimide PI-LTC9320, des NFs plus courts « buissonneux » pour les parylène C et N, et des NFs de diamètre 150 nm pour le parylène HT. Les analyses XPS sur les surfaces avant et après le plasma ont dévoilé un ratio oxygène/carbone plus important alors que l’angle de contact de départ (70 à 87°) reste le même ou devient plus élevé. La superhydrophobicité des NFs SU-8 et PI-LTC9320 semble s’expliquer par la forme des nanostructures indiquant une configuration Cassie-Baxter. Cette thèse expose aussi que les NFs SU-8 longs de 4 µm influencent positivement l’adhésion et le réseau de neurites de neurones, en comparaison aux NFs SU-8 de 1 µm, pour les cultures de cellules primaires corticales et rétinales. Toutefois, parmi les différents polymères plat et nanostructurés incluant SU-8, parylènes et polyimides, les parylènes plat se révèlent être les meilleurs pour les cultures de cellules corticales. Par rapport au parylène C plat, le parylène C nanostructuré a un effet variable sur les cultures de cellules de rétiniennes. Dans cette thèse aussi, afin de répondre aux critères de biocompatibilité, de stérilisation, de souplesse et de blindage électrique, un câble flexible adapté à la connexion d’implants souples haute densité (256 voies) a été réalisé en salle blanche avec succès (analyses MEB et EDX). Des polymères conducteurs possibles pour le blindage ont été identifiés mais des caractérisations électriques restent à établir en connectant les deux extrémités du câble par une connectique développée dans cette thèse. Enfin, la qualité de la connexion électrique entre le câble et l’implant, réalisée facilement via un « clip » imprimé en 3D et un film conducteur anisotrope doit être améliorée
The research about rehabilitation of motor functions or the exploration of the brain using neuroprostheses has two major issues addressed in this thesis: the implants must be of high biocompatibility in the long term and with a high electrode density. The literature reveals that surface nanostructuring can improve the adhesion and neurite network of neurons and that fine and flexible implants, composed of SU-8 polymers, polyimide or parylene, reduce the glial scar. This thesis shows that a plasma etching (argon, oxygen) forms vertical nanowires (NW) of SU-8 of diameter 50 to 100 nm and long up to 8 μm. NWs can be transposed to an implant made of 10 µm diameter SU8 wires. Also, gold deposition (10 nm) followed by plasma etching leads to vertical NWs of the same diameter and long up to 4,2 µm for polyimide PI-LTC9320, and to shorter "bushy" NWs for parylene C and N, and large diameter 150 nm NWs for parylene HT. The XPS analyzes on the surfaces before and after the plasma have revealed a greater oxygen / carbon ratio while the contact angle (70 to 87°) remain the same or becomes higher. The superhydrophobicity of SU-8 and PI-LTC9320 NWs seems to be explained by the shape of the NWs indicating a Cassie-Baxter configuration. This thesis also shows that 4 µm long SU-8 NWs positively influence the adhesion and neurite network of neurons, compared to 1 µm long SU-8 NWs, for primary cortical cell cultures. However, among the various nanostructured and flat polymers including SU-8, parylenes and polyimides, the flat parylenes reveals to be the best polymers for the cortical cell cultures. In comparison to flat parylene C, nanostructured parylene C has a variable effect on the retinal cell cultures. Also in this thesis, in order to meet the criteria of biocompatibility, sterilization, flexibility and electrical shielding, a flexible cable adapted to the connection of high density soft implants (256 channels) was successfully performed in a clean room (analyzes MEB and EDX). Possible conductive polymers for the shielding have been identified but electrical characterizations remain to be established by connecting the two ends of the cable by a connector developed in this thesis. Finally, the quality of the electrical connection between the cable and the implant, performed easily via a "clip" printed in 3D and anisotropic conductive film has to be improved

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Bakkum, Douglas James. "Dynamics of embodied dissociated cortical cultures for the control of hybrid biological robots". Diss., Atlanta, Ga. : Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/22596.

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Thesis (Ph. D.)--Mechanical Engineering, Georgia Institute of Technology, 2008.
Committee Chair: Steve M. Potter; Committee Member: Eric Schumacher; Committee Member: Robert J. Butera; Committee Member: Stephan P. DeWeerth; Committee Member: Thomas D. DeMarse.

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18

Chu, Kin Yan. "Synaptic gene regulations are mediated by the activation of nucleotide P2Y[subscript 2] receptors in cultured cortical neurons /". View abstract or full-text, 2008. http://library.ust.hk/cgi/db/thesis.pl?BIOL%202008%20CHU.

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Pas, Jolien. "Flexible neural probes with a fast bioresorbable shuttle : From in vitro to in vivo electrophysiological recordings". Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEM040/document.

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Nous étudions l'utilisation de l'électronique organique à l'interface du tissu nerveux pour des applications in vitro et in vivo. Le principal objectif est la fabrication d’interfaces neuronales flexibles pour enregistrer l'activité électrophysiologique de cellules neuronales sur de longues durées. À cette fin, nous utilisons du parylène-C comme substrat et le polymère conducteur poly(3,4-éthylène dioxythiophène):poly(styrène sulfonate) pour réduire l'impédance de l'interface cellule/électrode. En utilisant nos matrices de microélectrodes, nous montrons comment améliorer le rendement d'enregistrement avec un modèle 3D in vitro. La formation de clusters cellulaires 3D augmente considérablement le nombre d’enregistrements de potentiels d’action unitaires. In vivo, nous démontrons la fabrication de sondes de support en polymères biodégradables sur nos capteurs flexibles en utilisant une combinaison de polymères alcool polyvinylique et poly(lactique-co-glycolique). Alors que notre support d’insertion en PVA fournit la rigidité nécessaire à la pénétration, le revêtement PLGA retarde la dissolution du support afin de placer précisément les capteurs à l'intérieur du cerveau. Cela nous permet d’enregistrer en profondeur et, dans les conditions idéales, de minimiser les lésions cérébrales par rapport à les sondes traditionnelles rigides. Dans l'ensemble, nous avons réussi à effectuer des enregistrements électrophysiologiques avec nos propres microélectrodes et sondes invasives, améliorant le rendement d'enregistrements in vitro et démontrant que nos support d’insertion biodégradables pénètrent le cerveau. Ces résultats annoncent de prometteuses applications médicales futures
Neural interfaces are designed to unravel the mysteries of the brain and to restore the functions of paralyzed patients. Despite the success of traditional neural interfaces, these rigid devices are prone to failure within months after surgery. Mechanical mismatch with the soft neural tissue is believed to be one of the main causes. In this thesis, we studied the use of soft organic electronics to interface with neural tissue for both in vitro and in vivo applications. Parylene-based microelectrode arrays (MEAs) and depth probes were made, employing the conducting polymer poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) to reduce the impedance at the cell-electrode interface. In vitro, we thereby showed how to enhance the recording yield of MEAs by creating a three-dimensional model of neurospheres. We further report on the fabrication of a new biodegradable polymer shuttle for flexible depth probes based on the combination of poly(vinyl alcohol) (PVA) and poly(lactic-co-glycolic) (PLGA). In vivo, the PVA/PLGA- shuttled probes were acutely tested in mice and revealed promising electrophysiological results. More research remains necessary to evaluate its long-term function in vivo. In conclusion, our results demonstrate that bioresorbable polymers are capable of providing the required stiffness to penetrate the brain, which shows much promise for future neural applications. This work thereby shows that a long-term functional neural interface is not far from being developed

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20

Lin, Wei. "Studies of the Change of Intracellular Zinc Triggered by Exogenous NO and the Induction of Tolerance to OGD by Exogenous NO and Lipophilic Metal Chelators in Cultured Cortical Neurons". Ohio University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1242520481.

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21

Ortman, Robert L. "Sensory input encoding and readout methods for in vitro living neuronal networks". Thesis, Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/44856.

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Establishing and maintaining successful communication stands as a critical prerequisite for achieving the goals of inducing and studying advanced computation in small-scale living neuronal networks. The following work establishes a novel and effective method for communicating arbitrary "sensory" input information to cultures of living neurons, living neuronal networks (LNNs), consisting of approximately 20 000 rat cortical neurons plated on microelectrode arrays (MEAs) containing 60 electrodes. The sensory coding algorithm determines a set of effective codes (symbols), comprised of different spatio-temporal patterns of electrical stimulation, to which the LNN consistently produces unique responses to each individual symbol. The algorithm evaluates random sequences of candidate electrical stimulation patterns for evoked-response separability and reliability via a support vector machine (SVM)-based method, and employing the separability results as a fitness metric, a genetic algorithm subsequently constructs subsets of highly separable symbols (input patterns). Sustainable input/output (I/O) bit rates of 16-20 bits per second with a 10% symbol error rate resulted for time periods of approximately ten minutes to over ten hours. To further evaluate the resulting code sets' performance, I used the system to encode approximately ten hours of sinusoidal input into stimulation patterns that the algorithm selected and was able to recover the original signal with a normalized root-mean-square error of 20-30% using only the recorded LNN responses and trained SVM classifiers. Response variations over the course of several hours observed in the results of the sine wave I/O experiment suggest that the LNNs may retain some short-term memory of the previous input sample and undergo neuroplastic changes in the context of repeated stimulation with sensory coding patterns identified by the algorithm.

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22

Bagnard, Dominique. "Étude des mécanismes cellulaires et moléculaires impliqués dans le développement des connexions cortico-thalamiques : rôle des interactions axo-axonales et des Sémaphorines". Lyon 1, 1999. http://www.theses.fr/1999LYO1T197.

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Smith, I., M. Haag, Christopher I. Ugbode, D. Tams, Marcus Rattray, S. Przyborski, A. Bithell i B. J. Whalley. "Neuronal-glial populations form functional networks in a biocompatible 3D scaffold". 2015. http://hdl.handle.net/10454/7742.

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yes
Monolayers of neurons and glia have been employed for decades as tools for the study of cellular physiology and as the basis for a variety of standard toxicological assays. A variety of three dimensional (3D) culture techniques have been developed with the aim to produce cultures that recapitulate desirable features of intact. In this study, we investigated the effect of preparing primary mouse mixed neuron and glial cultures in the inert 3D scaffold, Alvetex. Using planar multielectrode arrays, we compared the spontaneous bioelectrical activity exhibited by neuroglial networks grown in the scaffold with that seen in the same cells prepared as conventional monolayer cultures. Two dimensional (monolayer; 2D) cultures exhibited a significantly higher spike firing rate than that seen in 3D cultures although no difference was seen in total signal power (<50 Hz) while pharmacological responsiveness of each culture type to antagonism of GABAAR, NMDAR and AMPAR was highly comparable. Interestingly, correlation of burst events, spike firing and total signal power (<50 Hz) revealed that local field potential events were associated with action potential driven bursts as was the case for 2D cultures. Moreover, glial morphology was more physiologically normal in 3D cultures. These results show that 3D culture in inert scaffolds represents a more physiologically normal preparation which has advantages for physiological, pharmacological, toxicological and drug development studies, particularly given the extensive use of such preparations in high throughput and high content systems.

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24

Silva, Juliana Couras Fernandes. "Characterization of synchronization periods in in vitro cultures of cortical neuronal networks with spontaneous activity". Dissertação, 2020. https://hdl.handle.net/10216/128876.

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Os sistemas neuronais exibem atividade espontânea coordenada essencial para a formação de circuitos neuronais dependentes da atividade que são relevantes em processos fisiológicos, como a formação de memória, e em processos não fisiológicos, como as convulsões. In vitro, as culturas corticais exibem atividade espontânea de curtos períodos de atividade altamente sincronizada - períodos de sincronização (PS) - intercalados com períodos de atividade assíncrona mais longos. Vários estudos investigaram os mecanismos por detrás da geração desta atividade espontânea, mas como os sistemas neuronais geram estes PSs ou se estes podem ser previstos dada a atividade prévia são questões que permanecem por esclarecer. Neste trabalho, mostramos que os PSs se podem classificar em agrupamentos com base nos seus motivos temporo-espaciais, na sua rede de ignição e na sua dinâmica. Além disso, em experiências com arrays de microeléctrodos, detetámos elétrodos cuja probabilidade de um SP acontecer dado que se registou atividade era mais alta do que o esperado, permitindo identificar estes elétrodos, e consequentemente neurónios, como preditores de PSs. Ademais, mostramos que os picos da correlação cruzada ocorrem entre elétrodos cuja atividade oscila entre dois modos de frequência, o que sugere que os neurónios registados por estes elétrodos podem ter um papel relevante na manutenção da atividade espontânea. Por fim, simulando redes corticais com regras de conectividade mínimas foi possível replicar o padrão de PSs com valores de taxas de disparo semelhantes às experiências, sugerindo, assim, componentes estruturais implicadas na sua geração. Em suma, os nossos resultados sugerem que a conectividade local, neurónios com um elevado grau de saída e sub-redes fechadas poderão ter um papel importante na sustentação da atividade espontânea que gera os PSs.
Neuronal systems show coordinated spontaneous activity that impacts activity-dependent circuit formation relevant for physiological processes as memory formation, and non-physiological processes, as epileptic seizures. In vitro cortical cultures show spontaneous activity of short periods of highly coordinated activity - the synchronization periods (SP) - intercalated with longer periods of lower asynchronous activity. Several studies have investigated the mechanisms underlying the generation of this spontaneous activity, but how the neuronal system generates these SPs or if they can be predicted given the previous activity remains unclear. In this work, we show that clusters of SPs can be formed based on the temporo-spatial motif of its activity, its ignition subnetwork and its dynamics. Furthermore, in experiments with microelectrode arrays, we were able to find electrodes whose probability of a SP being about to start given that the electrode registered a spike was high could be used as a metric to identify electrodes, and consequently neurons, acting as predictors. Moreover, we show that highly cross-correlated peak values occur between electrodes whose activity oscillates in two frequency modes, suggesting that these electrodes could play a role in sustaining the network's spontaneous activity. Finally, by simulating cortical networks with minimal connectivity rules it was possible to replicate the SP pattern whose network firing rate ranges matched the experiments, thus suggesting structural components implicated in its generation. Overall, our results suggest that local connectivity, high out degree neurons and closed-loop networks may play a role sustaining the spontaneous activity and generating the SP pattern.

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25

Silva, Juliana Couras Fernandes. "Characterization of synchronization periods in in vitro cultures of cortical neuronal networks with spontaneous activity". Master's thesis, 2020. https://hdl.handle.net/10216/128876.

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Os sistemas neuronais exibem atividade espontânea coordenada essencial para a formação de circuitos neuronais dependentes da atividade que são relevantes em processos fisiológicos, como a formação de memória, e em processos não fisiológicos, como as convulsões. In vitro, as culturas corticais exibem atividade espontânea de curtos períodos de atividade altamente sincronizada - períodos de sincronização (PS) - intercalados com períodos de atividade assíncrona mais longos. Vários estudos investigaram os mecanismos por detrás da geração desta atividade espontânea, mas como os sistemas neuronais geram estes PSs ou se estes podem ser previstos dada a atividade prévia são questões que permanecem por esclarecer. Neste trabalho, mostramos que os PSs se podem classificar em agrupamentos com base nos seus motivos temporo-espaciais, na sua rede de ignição e na sua dinâmica. Além disso, em experiências com arrays de microeléctrodos, detetámos elétrodos cuja probabilidade de um SP acontecer dado que se registou atividade era mais alta do que o esperado, permitindo identificar estes elétrodos, e consequentemente neurónios, como preditores de PSs. Ademais, mostramos que os picos da correlação cruzada ocorrem entre elétrodos cuja atividade oscila entre dois modos de frequência, o que sugere que os neurónios registados por estes elétrodos podem ter um papel relevante na manutenção da atividade espontânea. Por fim, simulando redes corticais com regras de conectividade mínimas foi possível replicar o padrão de PSs com valores de taxas de disparo semelhantes às experiências, sugerindo, assim, componentes estruturais implicadas na sua geração. Em suma, os nossos resultados sugerem que a conectividade local, neurónios com um elevado grau de saída e sub-redes fechadas poderão ter um papel importante na sustentação da atividade espontânea que gera os PSs.
Neuronal systems show coordinated spontaneous activity that impacts activity-dependent circuit formation relevant for physiological processes as memory formation, and non-physiological processes, as epileptic seizures. In vitro cortical cultures show spontaneous activity of short periods of highly coordinated activity - the synchronization periods (SP) - intercalated with longer periods of lower asynchronous activity. Several studies have investigated the mechanisms underlying the generation of this spontaneous activity, but how the neuronal system generates these SPs or if they can be predicted given the previous activity remains unclear. In this work, we show that clusters of SPs can be formed based on the temporo-spatial motif of its activity, its ignition subnetwork and its dynamics. Furthermore, in experiments with microelectrode arrays, we were able to find electrodes whose probability of a SP being about to start given that the electrode registered a spike was high could be used as a metric to identify electrodes, and consequently neurons, acting as predictors. Moreover, we show that highly cross-correlated peak values occur between electrodes whose activity oscillates in two frequency modes, suggesting that these electrodes could play a role in sustaining the network's spontaneous activity. Finally, by simulating cortical networks with minimal connectivity rules it was possible to replicate the SP pattern whose network firing rate ranges matched the experiments, thus suggesting structural components implicated in its generation. Overall, our results suggest that local connectivity, high out degree neurons and closed-loop networks may play a role sustaining the spontaneous activity and generating the SP pattern.

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26

Yen, Chih-Wei, i 顏志瑋. "The Effect of Serotonin Receptor on the Developmental Expression of NMDA Receptor on the Primary Cortical Neuronal Cultures". Thesis, 2005. http://ndltd.ncl.edu.tw/handle/51390315770983907959.

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碩士
臺北醫學大學
醫學研究所
93
Serotonin (5-HT) is known to regulate many developmental processes of serotonergic neurons and their target area through its many receptors with distinct characters and functions. In developing rat brain, the axons of serotonergic neuron reach the cortex around embryonic day 16, when neurogenesis is taking place. Previously, it has been shown that serotonin can promote the survival of cortical glutamatergic neurons in culture. Since the expression of NMDA receptor in cortex is after the development of serotonergic neurons, it is possible that the expression of NMDA receptor is under the influence of the activity of 5-HT and its receptors. To test this hypothesis, we used the rat primary cortical cell culture to determine whether long-term exposure of non-selective antagonists of 5-HT1/2 receptor, the methysergide maleate and dihydroergocristine mesylate, affected the expression of the NMDA receptor subunit protein, namely NR1, NR2A and NR2B, and whether the alteration of the receptor affected the sensitivity of cultured cell to the NMDA-induced neurotoxicity. Immunoblotting assay showed that the expressions of NR1, NR2A, and NR2B increased as increase in the day in vitro (DIV), and reached the plateau around DIV10 to 20. 10-day incubation with high concentration of the methysergide maleate (100μM) or dihydroergocristine mesylate (10μM) is cytotoxic to the cortical cell culture. However, low concentration of methysergide maleate (1μM or 10μM) or dihydroergocristine mesylate (1μM) did not produce cell toxicity. Long-term exposure to dihydroergocristine mesylate (1μM) significantly decreases the expression of NR1 and NR2A subunits. LDH assay showed that long-term exposure to methysergide maleate (10μM), dihydroergocristine mesylate (1μM), and pindolol (1μM), a selective antagonist of 5-HT1A and cyproheptadine hydrochloride (1μM), a selective antagonist of 5-HT2A, reduced the sensitivity of cell to NMDA-induced cell toxicity. This result showed that long-term decreasing the activity of serotonin receptor could decrease the expression of NMDA receptor in both quantitative and qualitative manner in developing cortical neuronal cultured cell.

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27

Tai, Yu-I., i 戴佑易. "Arsenite-induced neurotoxicity in rat cortical neuronal culture". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/85385353937903212389.

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碩士
國立陽明大學
生理學研究所
99
Chronic exposure to arsenite-contaminated water or foods may cause health problems, including cancers, cardiovascular diseases and neurotoxicity. Oxidative stress is known as one of the mechanisms underlying arsenite-induced neurotoxicity, such as arsenite-induced free radicals production and reduction in antioxidative defense systems. Necrosis and apoptosis (aka Type I programmed cell death) are reportedly involved in the arsenite-induced neurotoxicity. However, the involvement of autophagy (aka. type II programmed cell death) in arsenite-induced neurotoxicity remains to be determined. Autophagy, a self-eating mechanism, has been found to be induced by several stressed conditions, including toxins and starvation. Autophagy embraces proteins and cellular organelles which are then degraded by lysosomes; small molecules such as amino acids will be recycled for cell survival. In the present study, the role of autophagy in arsenite-induced neurotoxicity was studied using primary cortical neuronal culture. Cortical tissues from embryonic day 16-18 rats were dissected. At DIV7, cultured neurons were treated with sodium arsenite (arsenite, NaAsO2). Arsenite concentration- and time-dependently induced cell death. Arsenite was found to elevate HO-1 (a biomarker of oxidative stress) and cytochrome c oxidase levels (a hallmark of mitochondrial mass). Furthermore, arsenite induced 脉-spectrin degradation by concentration-dependent elevations in 150/145 kD and 120 kD汹脉-spectrin fragments, indicating that arsenite induced necrosis and apoptosis. Arsenite-induced reductions in procaspases 3 and 12 levels, suggesting that arsenite-induced apoptosis was mediated via both mitochondria and ER pathways. At the same time, induction of LC3-II (a hallmark protein of autophagy) was observed in arsenite-treated cells, indicating that arsenite induced autophagy. 3-Methyladenine (3MA, an autophagy inhibitor) was found to reduce LC3-II levels and attenuate arsenite-induced cell death, suggesting that autophagy plays a pro-death role in arsenite-induced neurotoxicity in the primary cortical neuronal culture. In addition, arsenite was found to time- and concentration-dependently inhibited 脉-synuclein levels, a presynaptic protein reportedly involved in the synaptogenesis, indicating that arsenite may disturb the development of nervous systems. Curcumin (diferulonylmethane) is known to possess anti-inflammatory, anti-oxidative and anti-cancer properties. In my study, the effect of curcumin on arsenite-induced neurotoxicity was investigated. Curcumin was found to inhibit arsenite-induced cell death. Furthermore, curcumin reduced arsenite-induced activation of caspase 3 and reduction of procaspase 12 levels, indicating that curcumin attenuated arsenite-induced apoptosis. Finally, curcumin inhibited arsenite-induced reduction in 脉-synuclein level. In conclusion, arsenite-induced neurotoxicity is mediated via necrosis, apoptosis and autophagy. Furthermore, arsenite reduced 脉-synuclein levels, indicating that arsenite may disturb the synaptogenesis. Moreover, curcumin significantly attenuated arsenite-induced necrosis, apoptosis and autophagy as well as arsenite- reduced 脉-synuclein levels, suggesting that curcumin may be therapeutically useful against neurodegeneration during development.

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28

Lin, Po-Wei, i 林柏維. "Neurotoxic effect of acrolein in primary cultured rat cortical neurons". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/60633236382900218659.

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碩士
國立陽明大學
藥理學研究所
102
Acrolein, a ubiquitous pollutant and a by-product of lipid peroxidation, possesses a strong oxidative activity. Clinical studies have been reported abundant acrolein in the brain of patients with CNS neurodegenerative diseases, including Parkinsonism and Alzheimer’s diseases. In my thesis, the neurotoxic effects of acrolein were studied using primary cultured cortical neurons: one was the direct neurotoxic effect of acrolein and the other was the effect of acrolein on glutamate/NMDA-induced neurotoxicity. The involvement of oxidative stress of acrolein was first identified by elevated fluorescent intensity of DCF-DA using flow cytometry and elevated heme oxygenase-1 (HO-1) level (a redox-regulated heat shock protein) using Western blot assay. Using MTT and LDH assay, acrolein was found to cause cell death in a concentration-dependent manner. Higher concentration of acrolein (30 μM) induced caspase-3 and caspase-12 activation, indicating ER stress was involved in acrolein-induced apoptosis. Meanwhile, acrolein decreased Cisd-2 level (a mitochondrial outer-membrane protein), indicating the involvement of mitochondrial dysfunction. N-acetylcysteine (NAC), an antioxidative agent significantly attenuated acrolein-induced neurotoxicity. While lower concentration of acrolein (10-20 μM) did not show significant neurotoxicity, lower acrolein did potentiate the G/N-induced HO-1 expression and pGSK-3β reduction, indicating acrolein enhanced G/N-induced oxidative stress. Moreover, lower acrolein potentiated G/N-induced neuronal loss, caspase-9 and caspase-12 activation as well as Bcl-2 reduction, indicating acrolein aggravated G/N-induced apoptosis. At the same time, lower acrolein potentiated G/N-induced α-synuclein and GAP-43 reduction and morphological damages, indicating vacuoles formation and inhibition of neurite outgrowth. In conclusion, acrolein-induced neurotoxicity may be mediated by oxidative stress and apoptosis. Furthermore, acrolein may aggravate G/N-induced neurotoxicity in primary cultured cortical neurons. Moreover, NAC may be a therapeutic useful for acrolein-induced neurotoxicity.

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29

Yi-Chun, Chen. "Characterization of cortical neurons outgrowth in 2D/3D culture system". 2003. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0007-1704200714530905.

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30

Chen, Yi-Chun, i 陳怡君. "Characterization of cortical neurons outgrowth in 2D/3D culture system". Thesis, 2003. http://ndltd.ncl.edu.tw/handle/61700223602322921800.

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碩士
臺北醫學大學
生物醫學材料研究所
91
There are many researches about neuron regeneration in the central nervous system (CNS) after injury, but many problems have remained to be solved. At present, there are two main approaches for promoting neuron regeneration: cell replacement and endogenous repair using artificial substrate implants. To improve the ability of regeneration by grafting living cells or adding growth factor into the lesion site, it is important to find a good biomaterial for the in-vitro study of neuron survival. A good biomaterial matrix has to supply normal neuronal differentiation and outgrowth. Our study focussed on two and three-dimensional biomaterials such as agarose, collagen and fibrin glue that expect to be a suitable biomaterial for neuron outgrowth. Cortical neuron were dissected from E17 rat embryos and cultured in agarose gel, collagen gel, fibrin glue and the mixture of collagen and fibrin. We found that the neuron cultured in collagen gel and fibrin glue have longer period of survival (over 3 weeks), and the neurite extension was better than in agarose gel. The survival rate using MTT and LDH assay, fibrin glue was the most suitable biomaterial for neuron survival among biomaterials examined. In 2D fibrin plating, neuron cells had cell aggregation and stress fibers, but did not find the same result in collagen gel. There is no difference of neurite extension and survival in the mixture of collagen and fibrin. The results suggest that collagen and fibrin can provide a suitable substrate for neuronal survival and differentiation.

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31

Chuang, Chih-Fan, i 莊智帆. "Unbiased Proteomic Study of the Axons of Cultured Rat Cortical Neurons". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/3dyhd6.

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博士
國立清華大學
分子醫學研究所
106
The axon is a long projection connecting a neuron to its targets. Here, the axons of cultured rat cortical neurons were isolated with micro-patterned chips that enable the separation of axons from their cell bodies. Proteins extracted from isolated axons and whole neurons were subjected to analyses using two-dimensional liquid chromatography-tandem mass spectrometry (2D-LC-MS/MS) analyses without and with stable isotope dimethyl labeling, resulting in the identification of >2,500 axonal proteins and 103 axon-enriched proteins. A strong correlation exists between the abundances of axonal proteins and their counterparts in whole neurons. The proteomic results confirm the axonal protein constituents of the subcellular structures documented in earlier electron microscopic studies. Cortical axons have proteins that are components of machineries for protein degradation and the synthesis of soluble, membrane, and secretory proteins, although axons lack conventional Golgi apparatus. Despite the fact that axons lack nucleus, nuclear proteins were identified, and 67 of them were found enriched in axons. Some of the results obtained by the MS-based studies were validated by quantitative Western blotting and immunofluorescence staining analyses. The results represent the first comprehensive description of the axonal protein landscape. The MS proteomics data are available via ProteomeXchange with identifier PXD005527.

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32

Teng, Yu-Chun, i 鄧郁君. "Role of autophagy in arsenite-induced neurotoxicity in primary cultured cortical neurons". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/52774311329750328165.

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碩士
國立陽明大學
生理學研究所
101
Chronic exposure to arsenite-contaminated water/food and arsenic therapy reportedly causes neurotoxicity. My thesis focused on the roles of heme oxygenase-1 (HO-1) and autophagy in arsenite-induced neurotoxicity using primary cultured cortical neurons. In addition to apoptosis, incubation with arsenite was found to elevate HO-1 level, a redox-regulated protein. HO-1siRNA transfection was employed to prevent arsenite-induced HO-1 elevation, caspase-3 activation and neuronal death, indicating that HO-1 is neuroprotective in the arsenite-induced neurotoxicity in primary cultured cortical neurons. As to the involvement of autophagy, our data showed that arsenite elevated LC3-II level (a hallmark of autophagy) which was attenuated by 3-methyladenine (3MA, an autophagy inhibitor) and enhanced by chloroquine (CQ, an inhibitor of autolysosome formation). Moreover, Atg7siRNA transfection reduced arsenite-induced LC3-II levels and caspase- 3 activation, suggesting that autophagy plays a pro-death role in the arsenite-induced neurotoxicity. At the same time, arsenite concentration- and time-dependently reduced α-synuclein levels (a presynaptic vesicle-related protein), growth associated protein 43 (GAP43) and peroxisome proliferator-activated receptor gamma coactivator-1α levels (PGC-1α, a regulator of mitochondrial biogenesis). 3MA and Atg7siRNA transfection reduced arsenite-induced reduction in α-synuclein, GAP43 and PGC-1α levels, indicating that arsenite may exert its neurotoxic action via degradation of α-synuclein and mitochondria biogenesis. The neurotoxic effects of arsenics, including arsenite, monomethylarsonous acid (MMAIII), arsenate and dimethylarsinic acid (DMAV) were compared; the cell viabilities of MMAIII, arsenite, DMAV and arsenate were 22±6%, 60±2%, 94±2% and 99±2% of control, respectively. Furthermore, the potency in autophagy activation was as followed: MMAIII >arsenite>>arsenate and DMAV. Moreover, co-incubation with glutathione attenuate arsenics-induced cell death, apoptosis, and autophagy, HO-1, Heat shock protein 60 (Hsp60), α-synuclein and PGC-1α levels, suggesting that oxidative stress is involved in the arsenics-induced neurotoxicity. The neuroprotective effect of melatonin on arsenite-induced neurotoxicity was demonstrated by melatonin-induced attenuation of arsenite-induced cell death, LC3-II elevation, and reduction in α-synuclein as well as PGC-1α levels. In conclusion, HO-1 elevation may be a neuroprotective strategy for arsenite-induced neurotoxicity. Furthermore, autophagy appears to be prodeath in the arsenite-induced neurotoxicity. Moreover, melatonin may be therapeutic useful for arsenite-induced neurotoxicity via attenuating autophagy and elevating α-synuclein as well as mitochondria biogenesis.

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33

Yeh, Nai-Hsing, i 葉乃馨. "Effects of NCS-1 and Auxilin-1 on Neurotransmission in Cultured Cortical Neurons". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/45253351616774724355.

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碩士
國立臺灣大學
生命科學系
103
Calcium influx in neurons is an important event in regulating various signaling pathways like neurotransmitter release and neurite outgrowth. Neuronal calcium sensor-1 (NCS-1) is a member of the EF-hand Ca2+ binding proteins and expressed mainly in nervous system. NCS-1 overexpression affects the vesicle recycling in bovine adrenal chromafﬁn cells (BC) and has little effect on Ca2+ channels. In our lab, we have also found that NCS-1 and Auxilin-1 (Aux-1), a protein assists endocytosis, have interaction via yeast-two-hybrid. We believe this interaction can be the key to regulate exocytosis and endocytosis. However, our results in protein pulldown assay shows that NCS-1 and Aux-1 have no direct binding activity. We suppose the interaction only exist under specific condition. To observe the effect of NCS-1 and Aux-1 on neurotransmission, we use Ca2+ imaging technique to visualize Ca2+ response after excitation. Our results demonstrate that NCS-1 overexpression inhibits [Ca2+]i elevation in both presynaptic and postsynaptic neurons, but NCS-1 mutants overexpression can enhance Ca2+ response in postsynaptic neurons and have different effect on target neurons. In the Aux-1 expressing neuron, the [Ca2+]i elevation is reduced, while in postsynaptic neurons is unaltered. Therefore, NCS-1 may play an inhibitory role in neurotransmission by regulating synaptic vesicle recycling, and Aux-1 may suppress Ca2+ response and support synaptic vesicle recycling.

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34

Yang, Benduan. "Adrenergic modulation of glutamate induced calcium mobilization in cultured rat visual cortical neurons". Thesis, 1994. http://hdl.handle.net/2429/3511.

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Since Wiesel and Hubel first discovered that the responsiveness of the cortical neurons in the striate cortex to visual stimuli via either eye was subject to postnatal developmental manipulation, three decades have passed in strenuous efforts to unravel the mechanism underlying this ocular dominance plasticity. Among these studies, a variety of neurotransmitters/neuromodulators, including noradrenalin, acetylcholine and serotonin, have been implicated at both system and cellular levels. In view of the facts that noradrenalin changes neuronal excitability and the N-Methyl-D-aspartate (NMDA) receptor plays a crucial role in neuroplasticity, this study was designed to obtain evidence whether adrenergic modification worked through interacting with glutamergic system in terms of calcium dynamics and how this process occurred. In primary neuronal cultures derived from the visual cortex of embryonic day 16-18 rats, intracellular free calcium concentration, [Ca²⁺]i, was increased by bath application of glutamate in a dose dependent manner. Noradrenalin applied alone had relatively small effects. However, when glutamate concentrations eliciting modest increases in [Ca²⁺]i were applied together with 1 µM noradrenalin, the increase in [Ca²⁺]i could be enhanced by a factor of up to eight in 147 neurons out of a total of 215 cells observed in 54 experiments. The observed enhancement was much more obvious at low doses of glutamate than with higher doses, augmenting all submaximal calcium responses to similar asymptotic levels. 2-Amino-5-phosphonovalerate (APV), the NMDA receptor antagonist, completely blocked the adrenergic enhancing effect (29/29 cells in 8 experiments). Among the antagonists specific to άl , ά2 and ϐ subtypes of adrenoceptors, the ϐ antagonist propranolol most completely blocked the enhancing effect (13/14 cells in 4 experiments, by an amplitude of 90%). The involvement of the ϐ receptor pathway was further supported by the ability of a cAMP analog to mimic the enhancing effect of noradrenalin. These results suggest that receptors for noradrenalin and glutamate colocalize on postsynaptic cortical cells and that adrenergic modulation of glutamate induced calcium influx most likely work through the ϐ receptor pathway. It is further postulated that ocular dominance plasticity may be at least partially implemented via a calcium dependent cascade.

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35

Ai-ChiangLee i 李艾薔. "Neuroplastic Effect of Prothymosin α in Cultured Cortical Neurons after Oxygen-Glucose Deprivation". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/v7pw5v.

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36

King, Chih En, i 金稚恩. "Different composition and expression in mRNA in axons of cultured cortical and hippocampal neurons". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/23561334636909642996.

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37

Rosa, Valeria de. "Aβ-mediated changes in CREB and ERK activity in cultured cortical neurons : involvement of NMDA receptors". Master's thesis, 2013. http://hdl.handle.net/10316/28867.

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Dissertação de mestrado em Biologia Molecular e Celular, apresentada ao Departamento de Ciências da Vida da Faculdade de Ciências e Tecnologia da Universidade de Coimbra.
Alzheimer’s disease (AD) is the most common neurodegenerative disorder in elderly. Typical hallmarks of this pathology are the extracellular deposits of amyloid-beta peptide (Aβ) peptide forming plaques and neurofibrillary tangles in the hippocampus and cortex, the main brain areas affected in AD. Many studies consider the accumulation of Aβ as “primum movens” for a cascade of events that ultimately produce massive neuronal death in selective neurons. cAMP response element-binding protein (CREB) is one of the main transcriptional factors involved in gene expression related to cell survival, memory formation and synaptic plasticity. In AD brain, CREB levels and activity were shown to be altered. In additon, extracellular-signal-regulated kinase (ERK) is involved in a cascade of events that can also modulate the activity of CREB through phosphorylation of specific kinases. Both CREB and ERK-associated signaling pathways are sensitive to intracellular Ca2+ changes (Ca2+ i), being Ca2+ i dyshomeostasis largely described to occur in AD. N-methyl-D-aspartate receptors (NMDARs) have a high Ca2+ conductance and are essential for synaptic plasticity, since they are connected to the excitability of post-synaptic membranes; however, overactivation of NMDARs causes excitotoxicity. In this work we evaluated the changes in CREB and ERK activities in mature cortical neurons exposed to Aβ1-42 oligomers and the involvement of NMDARs activation-mediated Ca2+ I rise in these cells. We further analysed the levels of a CREB target, PGC-1α, involved in mitochondrial biogenesis and in antioxidant response. Our findings show that incubation with Aβ1-42 oligomers produces early changes in the levels of phosphorylated CREB, reflecting CREB activity, in a process mediated by influx of Ca2+ occurring through the activation of NMDARs. A similar pattern of activation was observed for ERK, suggesting that both pathways can be connected in the response to Aβ exposure. Interestingly, ERK and CREB activation after Aβ1-42 exposure were largely modulated by GluN2Acomposed NMDARs, which are mostly present in synaptic sites. Moreover, protein levels of PGC-1α increased for the same time of exposure and this effect was also mediated by NMDARs activations, suggesting that Aβ-induced early control of PGC-1α levels may help to counteract late neurotoxic effects induced by exposure to Aβ oligomers. Moreover, prolonged Aβ exposure induced a decrease in nuclear CREB, supporting a late decline in pro-survival functions of this transcription factor. Overall, data suggest that early exposure to oligomeric Aβ1-42 exerts beneficial effects in mature cortical neurons through the activation of ERK-CREB signaling pathways, possibly linked to the activation of synaptic NMDARs.
A doença de Alzheimer (DA) é a doença neurodegenerativa mais comum no idoso. De entre os marcadores típicos da doença encontram-se as placas senis, constituídas por depósitos extracelulares do peptídeo beta-amilóide (Aβ) e as tranças neurofibrilares, cuja acumulação ocorre no hipocampo e no córtex, as duas áreas cerebrais mais afetadas na DA. Muitos estudos consideram a acumulação de Aβ como “primo movens” para a cascata de eventos causadores da morte neuronal maciça que ocorre na DA. O CREB é um dos fatores de transcrição mais importantes envolvidos na expressão de genes que conduzem à sobrevivência celular, nos processos de formação da memória, assim como na plasticidade sinática. Na DA, os níveis proteicos e a atividade do CREB têm mostrado estarem alterados. Para além disso, a ERK parece estar envolvida numa cascata de eventos que modulam, por sua vez, a atividade do CREB através da fosforilação de cinases específicas. As vias de sinalização associadas ao CREB e à ERK são sensíveis a alterações dos níveis do cálcio intracelular (Ca2+i) cuja homeostasia está desregulada na DA. Os recetores do NMDA (NMDARs) apresentam uma condutância elevada ao Ca2+, sendo a sua atividade essencial para a plasticidade sinática, uma vez que estes recetores se apresentam acoplados à excitabilidade da membrana pós-sinática; contudo, uma hiperestimulação dos NMDARs causa excitotoxicidade. Neste trabalho foram avaliadas as alterações na atividade do CREB e da ERK em neurónios corticais expostos a oligómeros de Aβ1-42, bem como o envolvimento dos NMDARs e da dependência do Ca2+ extracelular nestas células. Para além disso, analisaram-se os níveis de PGC-1a, um alvo do CREB envolvido na biogénese mitocondrial e na resposta antioxidante. Os resultados mostram que a incubação com oligómeros de Aβ1-42 produz alterações precoces nos níveis de fosforilação do CREB, refletindo a atividade do CREB, por um processo dependente do influxo de Ca2+ através dos NMDARs. Um padrão de ativação análogo foi observado para a ERK, sugerindo que as duas vias poderão estar interligadas em resposta à exposição a Aβ. Surpreendentemente, a ativação da ERK e do CREB nestas condições parece ser modulada por NMDARs contendo a subunidade GluN2A, presente maioritariamente na sinapse. Para além disso, os níveis proteicos de PGC-1a aumentaram para o mesmo tempo de exposição ao Aβ, sendo este efeito modulado também pelos NMDARs, o que sugere que o Aβ controla precocemente os níveis de PGC-1a no sentido de impedir efeitos neurotóxicos induzidos pela exposição aos oligómeros de Aβ. Também foi observado que a exposição prolongada a Aβ induziu um decréscimo dos níveis nucleares do CREB, o que está de acordo com o decréscimo tardio nas funções de sobrevivência características deste fator de transcrição. No conjunto, os dados apresentados neste trabalho sugerem que uma exposição imediata aos oligómeros de Aβ exerce efeitos benéficos nos neurónios maduros do córtex, através da ativação das vias de sinalização ERK-CREB, possivelmente associadas à ativação dos NMDARs sináticos.

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38

De, Rosa Valeria. "Aβ-mediated changes in CREB and ERK activity in cultured cortical neurons: involvement of NMDA receptors". Master's thesis, 2013. http://hdl.handle.net/10316/24660.

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Dissertação de mestrado em Biologia Celular e Molecular, apresentada ao Departamento Ciências da Vida da Faculdade de Ciências e Tecnologia da Universidade de Coimbra.
A doença de Alzheimer (DA) é a doença neurodegenerativa mais comum no idoso. De entre os marcadores típicos da doença encontram-se as placas senis, constituídas por depósitos extracelulares do peptídeo beta-amilóide (Aβ) e as tranças neurofibrilares, cuja acumulação ocorre no hipocampo e no córtex, as duas áreas cerebrais mais afetadas na DA. Muitos estudos consideram a acumulação de Aβ como “primo movens” para a cascata de eventos causadores da morte neuronal maciça que ocorre na DA. O CREB é um dos fatores de transcrição mais importantes envolvidos na expressão de genes que conduzem à sobrevivência celular, nos processos de formação da memória, assim como na plasticidade sinática. Na DA, os níveis proteicos e a atividade do CREB têm mostrado estarem alterados. Para além disso, a ERK parece estar envolvida numa cascata de eventos que modulam, por sua vez, a atividade do CREB através da fosforilação de cinases específicas. As vias de sinalização associadas ao CREB e à ERK são sensíveis a alterações dos níveis do cálcio intracelular (Ca2+i) cuja homeostasia está desregulada na DA. Os recetores do NMDA (NMDARs) apresentam uma condutância elevada ao Ca2+, sendo a sua atividade essencial para a plasticidade sinática, uma vez que estes recetores se apresentam acoplados à excitabilidade da membrana pós-sinática; contudo, uma hiperestimulação dos NMDARs causa excitotoxicidade. Neste trabalho foram avaliadas as alterações na atividade do CREB e da ERK em neurónios corticais expostos a oligómeros de Aβ1-42, bem como o envolvimento dos NMDARs e da dependência do Ca2+ extracelular nestas células. Para além disso, analisaram-se os níveis de PGC-1a, um alvo do CREB envolvido na biogénese mitocondrial e na resposta antioxidante. Os resultados mostram que a incubação com oligómeros de Aβ1-42 produz alterações precoces nos níveis de fosforilação do CREB, refletindo a atividade do CREB, por um processo dependente do influxo de Ca2+ através dos NMDARs. Um padrão de ativação análogo foi observado para a ERK, sugerindo que as duas vias poderão estar interligadas em resposta à exposição a Aβ. Surpreendentemente, a ativação da ERK e do CREB nestas condições parece ser modulada por NMDARs contendo a subunidade GluN2A, presente maioritariamente na sinapse. Para além disso, os níveis proteicos de PGC-1a aumentaram para o mesmo tempo de exposição ao Aβ, sendo este efeito modulado também pelos NMDARs, o que sugere que o Aβ controla precocemente os níveis de PGC-1a no sentido de impedir efeitos neurotóxicos induzidos pela exposição aos oligómeros de Aβ. Também foi observado que a exposição prolongada a Aβ induziu um decréscimo dos níveis nucleares do CREB, o que está de acordo com o decréscimo tardio nas funções de sobrevivência características deste fator de transcrição. No conjunto, os dados apresentados neste trabalho sugerem que uma exposição imediata aos oligómeros de Aβ exerce efeitos benéficos nos neurónios maduros do córtex, através da ativação das vias de sinalização ERK-CREB, possivelmente associadas à ativação dos NMDARs sináticos.
Alzheimer’s disease (AD) is the most common neurodegenerative disorder in elderly. Typical hallmarks of this pathology are the extracellular deposits of amyloid-beta peptide (Aβ) peptide forming plaques and neurofibrillary tangles in the hippocampus and cortex, the main brain areas affected in AD. Many studies consider the accumulation of Aβ as “primum movens” for a cascade of events that ultimately produce massive neuronal death in selective neurons. cAMP response element-binding protein (CREB) is one of the main transcriptional factors involved in gene expression related to cell survival, memory formation and synaptic plasticity. In AD brain, CREB levels and activity were shown to be altered. In additon, extracellular-signal-regulated kinase (ERK) is involved in a cascade of events that can also modulate the activity of CREB through phosphorylation of specific kinases. Both CREB and ERK-associated signaling pathways are sensitive to intracellular Ca2+ changes (Ca2+ i), being Ca2+ i dyshomeostasis largely described to occur in AD. N-methyl-D-aspartate receptors (NMDARs) have a high Ca2+ conductance and are essential for synaptic plasticity, since they are connected to the excitability of post-synaptic membranes; however, overactivation of NMDARs causes excitotoxicity. In this work we evaluated the changes in CREB and ERK activities in mature cortical neurons exposed to Aβ1-42 oligomers and the involvement of NMDARs activation-mediated Ca2+ I rise in these cells. We further analysed the levels of a CREB target, PGC-1α, involved in mitochondrial biogenesis and in antioxidant response. Our findings show that incubation with Aβ1-42 oligomers produces early changes in the levels of phosphorylated CREB, reflecting CREB activity, in a process mediated by influx of Ca2+ occurring through the activation of NMDARs. A similar pattern of activation was observed for ERK, suggesting that both pathways can be connected in the response to Aβ exposure. Interestingly, ERK and CREB activation after Aβ1-42 exposure were largely modulated by GluN2Acomposed NMDARs, which are mostly present in synaptic sites. Moreover, protein levels of PGC-1α increased for the same time of exposure and this effect was also mediated by NMDARs activations, suggesting that Aβ-induced early control of PGC-1α levels may help to counteract late neurotoxic effects induced by exposure to Aβ oligomers. Moreover, prolonged Aβ exposure induced a decrease in nuclear CREB, supporting a late decline in pro-survival functions of this transcription factor. Overall,data suggest that early exposure to oligomeric Aβ1-42 exerts beneficial effects in mature cortical neurons through the activation of ERK-CREB signaling pathways, possibly linked to the activation of synaptic NMDARs.

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39

王志煜. "Effect of Ethanol on Nitric Oxide Generation in Primary Cultures of Cortical Neurons and Mixed Glia fron the Rat". Thesis, 1997. http://ndltd.ncl.edu.tw/handle/98258221661045308138.

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碩士
國防醫學院
生理學研究所
85
Some evidence suggests that nitric oxide (NO) may be involved in the central actions of ethanol. The physiological role of NO is now recognized as a neurotransmitter or neuromodulator, a vasodilator, and an immunomodulator. However, NO may have a "double-edged" role, i.e. neuroprotection and neurotoxicity, depending on the cellular source of NO and its targets, the amount of NO being produced, and redox state of the tissue. Endogenous NO is formed by NO synthase (NOS) from L-arginine. Three different isoforms of NOS (endothelial, neuronal and inducible) have been described in various cells in the brain. The endothelial and neuronal types of NOS are constitutive isoforms (cNOS). The inducible nitric oxide synthase (iNOS) in glial cells, macrophages and vascular smooth muscle cells is expressed only under pathological conditions. It has been recently suggested that NO from either neuronal or glial souce may participate the common mechanism of neurodegenerative diseases. Increased NO production by neurons may contribute to excitotoxicity. Activation of glial cells (by immune stimuli or cytokines) and enhanced production of NO has also been linked to neurotoxicity and neurodegenerative diseases. Using primary culture of rat cortical neurons and mixed glia, we attempted to examine the effect of ethanol on NO generation and cellular injury. In the first part of this thesis, we examined the-direct effect of ethanol on NO production and indirect effect through N-methyl-D-aspartate (NMDA) receptor system in neurons. In the second part of this thesis, we examined the direct effect of ethanol on NO production and indirect effect through iNOS induction by lipopolysaccharide (LPS) in mixed glial cultures. Neuronal and mixed glia cultures were prepared from embryonic (E17-E18) and neonatal (N1) Sprague-Dawley rats, respectively. Degree of cellular damage due to the toxicity of NMDA and LPS were evaluated by the morphological estimation under phase-contrast microscope and further confirmed by the measurement of activity of lactate dehydrogenase (LDH) in the bathing medium. The levels of NO production were examined by measurement of nitrite, the stable metabolite of NO, in the medium. Our neuronal cultures consisted of approximately 90% neurons and 10% glia, while mixed glia cultures consisted of 80% astroglia and 20% microglia. The results indicated that ethanol alone at all concentrations (1-400 mM) exerts no influence on neuronal viability and NO production. NMDA exhibited a concentration- and time- dependent toxicity in neurons. Exposure to NMDA (300μM, 25 min) caused about 60%~70% neuronal death and nitrite accumulation in neuronal culture. Ethanol treatment following NMDA exposure could not attenuate the NO production and cell injury. However, pretreating the neuronal cultures with ethanol (25-400 mM) for 10 minutes resulted in a concentration-dependent inhibition of NMDA neurotoxicity, but ethanol exerted no effects on NMDA receptor-mediated NO production. In contrast, LPS-induced NO production and iNOS expression from mixed glia was inhibited by ethanol, but the degree of cell-injury was not increased by either treatment with LPS or LPS together with ethanol. In conclusion, in neuronal cultures, ethanol by itself is not neurotoxic and even protective against NMDA neurotoxicity; however, the protection is not mainly through changing levels of NMDA receptor-mediated NO production through cNOS. In mixed glial cultures, LPS induces concentration- and time-dependent NO production through iNOS. In the absence of LPS, ethanol fails to induce iNOS expression. However, ethanol inhibits LPS-induced gene expression of iNOS and NO production.

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40

Chen, Hung-Lun, i 陳泓綸. "Effects of (-)-Epicatechin-3-gallate on the currents of Na(v)1.4 and Primary Cultured Embryonic Cortical Neurons". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/81975177804809014779.

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碩士
國立臺灣大學
腦與心智科學研究所
101
Consuming green tea refreshes the mind and provides many health benefits. Catechins have the ability against the oxidative damages in vitro and in vivo, and their effects on signal transduction pathways are associated with cell death and cell survival. Besides, (-)-epigallocatechin-3-gallate (ECGC) has the effects as anti-carcinogenesis, anti-hypertension, and lowering cardiovascular disease risk. Furthermore, EGCG and (-)-epicatechin-3-gallate (ECG) have effects on neural activities by modulating the ion channel activities, especially the voltage-gated sodium channels (VGSCs). To verify how catechins modulate the VGSC activities, primary cultured embryonic cortical neurons and HEK 293T cells which expressed Na(v)1.4 were patch-clamped in whole-cell mode, and sodium currents were recorded before and after ECG (30 μM) treatment. Our results suggested ECG slows the slow decay of neuronal sodium currents, whereas ECG did not alter the voltage-dependence activation of neuronal VGSCs. ECG shifts the inactivation curve negatively and lengthens the recovery from inactivation. Besides, ECG slows the decay of Na(v)1.4 current, and shifts the activation curve towards negative voltage. ECG shifts the inactivation curve positively and reduces the steady-state recovery of Na(v)1.4. To investigate how ECG affects the synaptic transmission in neuron, we applied the Fluo-2, a calcium dye, and MNI-glutamate to stimulate the target neuron locally by 405-nm laser. The preliminary results suggested that ECG may have an inhibitory effect on synaptic transmission in cortical neurons. These findings reveal the new knowledge about the modulation of ECG on VGSC, and ECG has different effects on kinetics of different VGSC subtypes.

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41

He, You-Hao, i 何祐豪. "The Roles of NLRP3-Caspase 1 Pathway in Zn2+-induced Cell Death of Primary-Cultured Rat Embryonic Cortical Neuron". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/73vr9a.

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碩士
國立臺灣大學
生命科學系
107
Parkinson’s disease (PD) is the second most common neurodegenerative disease, affecting about 2% of the world’s population over 60 years old. The pathogenic mechanism of PD is the loss of dopaminergic neurons in the substantia nigra (SN), which may be caused by the oxidative stress, mitochondrial dysfunction, DNA damage, microglial cell activation etc. Our previous work has verified that dopamine (DA) can induce autophagy and elevate intracellular Zn2+ concentration resulting in the death of cultured neurons, however, it is not clear the roles Zn2+ plays in these processes. Our preliminary results using NGS analysis shows that DA treatment increase the expression of IL-1β and several neuroinflammation-related genes suggesting the involvement of pyroptosis but not well-characterized yet. It is not clear how Zn2+-neuroinflammation pathway causes the cell death; therefore, we further investigated the roles of inflammasome plays in primary cultured rat embryonic cortical neurons after DA or Zn2+ treatment. We treated the neurons with DA (250 µM) and /or Zn2+ (200 µM) for 18 hrs to induce neuron death and tested the effects of inhibitor against the NLRP3-inflammasome pathway. MCC950, an NLRP3-inflammasome inhibitor, reduced ZnCl2-induced neuron death. VX-765 (caspase 1 inhibitor) can reverse the ZnCl2-induced neuron death. Therefore, these results suggest the involvement of neuroinflammation in Zn2+-induced cell death, which may be mediated by the pyroptosis pathway. The PCR results show that the expression levels of IL-1β increased under the DA and Zn2+ treatment. Our findings provide a new mechanism involved in DA-induced neuron death from which we can develop a new therapeutic strategy to alleviate the neurodegeneration.

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42

Weng, Ju Chen, i 翁若甄. "Analyzing hnRNP-Q expression and hnRNP-Q-containing granules protein composition in the axons of rat cortical neurons in culture". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/w3428f.

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碩士
國立清華大學
系統神經科學研究所
103
Local protein synthesis in axons has been proposed to participate in the basal level growth, navigation and synaptogensis of axons. A large population of mRNA has been identified in the axons of different neurons. These mRNAs are believed to travel to the axon after being packed in ribonucleoprotein granules. The protein and microRNA components of these granules participate in not only the transport of mRNA, but they also regulate the splicing and editing of precursor mRNA and the translation of mRNA. Here, we culture rat cortical neurons of embryonic day 18 (E18) on a micropattern-coated glass chip, on which pure axons are guided to grow in designated areas. By means of fluorescence immunocytochemistry, hnRNP (heterogeneous nuclear ribonucleoprotein)-Q is found in axons. Upon treatments with brain-derived neurotrophic factorn (BDNF), hnRNP-Q expression level in axons increases. However, such increase in axons does not occur in axons which have been severed from their cell bodies. This finding indicates the trafficking of hnRNP-Q from somatodendrites to the axon after BDNF treatment. I have also isolated the proteins associated with hnRNP-Q from the lysates of cultured rat cortical neurons which have or have not been treated with BDNF by using immunoprecipitation. The co-immunoprecipitated proteins are first separated by gel-electrophoresis, subjected to in-gel digestion and finally identified by mass spectrometry. The results will shed lights to understanding the mechanism(s) underlying the transport of mRNAs in neurons when subjected to various stimulations.

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43

Hung, Hui-Hsing, i 洪慧馨. "The Roles of Intracellular Zinc Elevation in the Dopamine-induced Autophagy Activation in PC12 Cells and Cultured Rat Embryonic Cortical Neurons". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/58817010407339367167.

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博士
國立臺灣大學
生命科學系
104
Zinc ion (Zn2+), one of the most abundant trace metals in the brain, is essential for neuronal activities but induces toxicity when the concentration is abnormally high. Dopamine is an important neurotransmitter and is involved in autophagy, apoptosis, and neuromodulation. Autophagy plays an important dual role in neuronal cell death and cell survival. However, the mechanism behind the toxic effects of dopamine in neurodegenerative diseases is not clear. In this report, we first characterized how the high concentrations of dopamine and Zn2+ induced autophagy in PC12 cells and cultured embryonic cortical neurons; then investigated how dopamine elevated the intracellular Zn2+ concentration ([Zn2+]i) for autophagy activation. High concentrations of dopamine and Zn2+ increased the number and size of the aggregates of EGFP-LC3 expressed in cells as an indicator of autophagosome formation. The Western blot analysis showed the lipidation level of LC3 increased by these treatments in PC12 cells and cultured neurons. Introducing siRNA against ATG7, an initiator protein of autophagy, and blocking the phosphatidylinositol 3-phosphate kinase inhibited the formation of EGFP-LC3 aggregates in PC12 cells. In addition, blocking autophagosome formation increased the level of phosphatidylserine exposure on the outer membrane leaflet in PC12 cells when treated with dopamine or Zn2+. Dopamine or Zn2+ treatment significantly elevated [Zn2+]i; however, pretreatment of PC12 cells and neurons with a Zn2+ chelator suppressed the dopamine-induced autophagosome formation and LC3 lipidation. In neurons, inhibitors against the dopamine D1-like receptor, cAMP-dependent protein kinase (PKA), and NO synthase suppressed the dopamine-induced [Zn2+]i elevation. PKA activators and NO generators directly elevated the [Zn2+]i in cultured neurons. Using cell fractionation, proteins with M.W. values between 5 and 10 kDa were found to release Zn2+ following NO stimulation. In addition, chelating the [Zn2+]i elevation blocked the NO-activated autophagy. Therefore, our results indicate that treating cells with dopamine and Zn2+ results in the activation of the autophagy pathway in an effort to enhance cell survival. Furthermore, we demonstrate that the dopamine-induced [Zn2+]i elevation is mediated by the D1-like receptor-PKA-NO pathway and is crucial for autophagy activation.

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44

Chen, Der-cherng, i 陳德誠. "Mechanisms of stromal cell-derived factor-1α(SDF-1α) exerted neuroprotective effect in H2O2-induced neurotoxicity in primary cortical neuron culture". Thesis, 2006. http://ndltd.ncl.edu.tw/handle/35512284903746717916.

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碩士
慈濟大學
醫學研究所
94
Stroke is a leading cause of mortality in Taiwan. Post stroke disability can be a heavy burden for our society. Many researches focus on the stroke prevention. There was no effective therapies during acute ischemic type stoke. Recently many researches focused on cell therapy for degenerative neuron disease. Stem cell therapy for acute ischemic type stroke could be a feasible treatment despite its ethic consideration. Stromal cell-derived factor 1α (SDF-1α), constitutively expressed by all tissues, is involved in the trafficking of hematopoietic stem cells (HSCs) from bone marrow to peripheral blood and increased expression of SDF-1α has been found in the penumbra of the ischemic brain. Thus, we supposed intracerebral administration of SDF-1α could be a viable therapeutic strategy for cerebral ischemia in a stroke rat model. In this in vitro study we investigated whether SDF-1α could exert neuroprotective effects that rescued primary cortical neuron cultures from H2O2 induced neurotoxicity and modulated neurotrophic factors expression using QRT-PCR analysis.

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45

Eh, Julius Marcus Klaus. "Untersuchung des Zusammenhangs zwischen SUMO2/3-Konjugaten und Zellstress in einem In-vitro-Modell". Doctoral thesis, 2020. http://hdl.handle.net/21.11130/00-1735-0000-0005-1526-9.

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46

Tsai, Fan-Shiu, i 蔡汎修. "The attenuating effects of luteolin on amyloid β-peptide induced memory impairment in rats and molecular mechanism of neuroprotection in cultured rat cortical neurons". Thesis, 2007. http://ndltd.ncl.edu.tw/handle/75245509433073898359.

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博士
中國醫藥大學
中國藥學研究所博士班
95
The major clinical sign of Alzheimer’s disease (AD) is memory loss. The pathogenic character of AD is senile plaques result from aggregation of amyloid β peptide (Aβ) that caused apoptosis and neurodegeneration. On this basis, we studied the characteristics of Aβ induced memory impairment in animal and apoptosis in culture cell. We evaluated the memory function by passive avoidance and water maze in rats which injected with Aβ-(1-40) intra- nucleus basalis of magnocellularis. We further measured superoxide dimustase and glutathione levels in rat cortex and hippocampus to understand the mechanism of luteolin on Aβ-(1-40) induced memory impairment. In cell culture, we treated in primary cortical cell culture with Aβ-(25-35), and evaluated the neruoprotective mechanisms of luteolin by western blot, MTT assay and DNA fragmentation. In animal model, our results demonstrated that luteolin possessed protective effect on Aβ-induced memory impairment in water maze. Its mechanism might be related to antioxidant activity. In primary cortical cell culture, our results demonstrataed that the protective effect of luteolin on Aβ-(25-35)-induced apoptosis was mediated by the activation of phospho-ERK, JNK, phospho-JNK, phospho-P38 and caspase 3 in rat cortical neuron. From these results, we suggested that the attenuating effect of luteolin on the deficits of avoidance performance and water maze in rats and apoptosis in cultured rat cortical neurons induced by amyloid may be related to the decreases in the activities of oxidative stress, MAPK pathway and caspase 3.

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Rozprawy doktorskie na temat „Cortical neuronal cultures”

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