Rozprawy doktorskie: „Olfactory stem cells”

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Wetzig, Andrew R., i n/a. "Olfactory Stem Cells From Adult Rats". Griffith University. School of Biomolecular and Biomedical Science, 2007. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20070724.121953.

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The formation of neurospheres was important in demonstrating that neurogenesis in the adult brain may be fuelled by a stem cell population. The olfactory mucosa is another site of neurogenesis which, in humans, has been observed to contain a stem cell population through the formation of neurospheres (Murrell et al., 2005). Stem cells can be defined as cells capable of self-renewal and multipotency. The aim of this study was to investigate the potential of rat olfactory stem cells growing as neurospheres. The hypothesis is that the rat olfactory mucosa contains a 'true' stem cell population that can be cultured as neurospheres and that will demonstrate multipotency by differentiating into 'non-olfactory' cell types and possess the capacity for self-renewal, if provided with the appropriate environmental niche. Here it was found that adult rat olfactory mucosa is capable of generating neurospheres when cultured in EGF and bFGF. Evidence of self-renewal was provided by the formation of six generations of neurospheres, the formation of neurospheres from single cells and the expression of markers associated with self-renewal by neurosphere cells. The multipotency of olfactory neurosphere cells was demonstrated through manipulation of the stem cell niche. In defined culture conditions, extracellular matrix molecules and growth factors were able to induce the differentiation of neurosphere cells down the dopaminergic lineage pathway. When co-cultured with differentiating cells, neonatal myoblasts and 3T3-L1 cells, olfactory neurosphere cells were able to differentiate and incorporate into a skeletal muscle myotube and differentiate into adipocytes, respectively. In conclusion it was found that the adult rat olfactory mucosa is capable of generating neurospheres. When presented with an appropriate niche neurosphere cells are able to self-renew and demonstrate multipotency.

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Sacramento, Sónia Raquel Capela. "Establishing model systems from olfactory mucosa stem cells". Master's thesis, Universidade de Aveiro, 2013. http://hdl.handle.net/10773/11806.

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Mestrado em Biomedicina Molecular
As células estaminais são uma classe distinta de células, devido às suas capacidades de regeneração e diferenciação em vários tipos de células especializadas. Os nichos onde estas se encontram servem-lhes de sustentação e permitem a sua manutenção num estado indiferenciado, afectando a sua regeneração e diferenciação através de estímulos. As células estaminais dividem-se em duas classes: embrionárias (pluripotentes) e adultas (multipotentes), embora também existam células estaminais pluripotentes induzidas. Nos últimos anos tem-se estudado a possibilidade de utilizar sistemas baseados em células estaminais no estudo de neuropatologias. Assim sendo, os objectivos desta dissertação foram o isolamento e proliferação de células estaminais da mucosa olfactiva, a indução destas células para a formação de neurosferas e a sua diferenciação para células tipo neuronais (NLC) e células derivadas de neurosferas (ONS). Também se procedeu à diferenciação das ONS e à caracterização dos modelos celulares NLC e ONS. Para se atingir os objectivos definidos, foram recolhidas biópsias de mucosa olfactiva e isolaram-se células estaminais de epitélio e da lâmina própria. As células estaminais da mucosa olfactiva proliferaram e foram induzidas a formar neurosferas com um meio de cultura específico (DMEM/F12 com ITS-X, EGF e FGF2). As neurosferas foram posteriormente diferenciadas em células ONS (com meio DMEM/F12) e em NLC (com meio neurobasal suplementado com NGF, B27, glutamina e glutamato). Imagens obtidas durante o tempo de diferenciação das NLC foram analisadas tendo em conta parâmetros morfométricos. As células ONS foram adaptadas à cultura em meio sem soro e diferenciadas em células tipo neurónios (usando meio DMEM/F12 com N2 e meio DMEM/F12 com B27). Os resultados obtidos indicam que estabelecemos culturas primárias de células estaminais da mucosa olfactiva de rato. A eficiência dos protocolos de isolamento e proliferação foi confirmada pela marcação com nestina através de imunofluorescência e pela formação de neurosferas. A análise morfométrica das NLC indicou que diferenciámos as neurosferas para células tipo neuronal, devido à sua morfologia neuronal e à expressão do marcador neuronal β-tubulina III. Foram também estabelecidas culturas de células ONS, posteriormente diferenciadas através da redução de soro, apresentando um fenótipo tipo neuronal quando mantidas em meio definido. Contudo, devem ser realizadas experiências futuras para a caracterização deste novo modelo celular. Os nossos resultados permitem-nos concluir que estabelecemos e caracterizámos novos sistemas modelo baseados em células estaminais. Estes resultados são relevantes uma vez que tais modelos podem ser usados para o estudo de mecanismos celulares e moleculares envolvidos em inúmeras neuropatologias, nomeadamente na Doença de Alzheimer.
Stem cells are a distinct class of cells, characterized by their ability to self-renew and differentiate into several specialized cell types. The niche of stem cells provides them support, favors their existence in an undifferentiated state and affects, by stimuli, their self-renewal and cellular fate. Stem cells can be divided in two broad classes: embryonic (pluripotent) and somatic stem cells (multipotent), although induced pluripotent stem cells are also a reality nowadays. The possibility of investigating neuropathologies using stem cell based systems has attracted interest among researchers in the last few years. Therefore, the main objectives of this dissertation were the isolation and proliferation of olfactory mucosa stem cells that were further induced to form neurospheres and further differentiated into neuron-like cells (NLC) and olfactory neurosphere-derived cells (ONS). ONS differentiation and the characterization of NLC and ONS model systems were also performed. For the accomplishment of these objectives, olfactory mucosa biopsies were collected and epithelium and lamina propria stem cells isolated. The well proliferating olfactory mucosa stem cells were induced to form neurospheres using a specific culture medium (DMEM/F12 supplemented with ITS-X, EGF and FGF2). The neurospheres were then differentiated into ONS cells (using DMEM/F12 medium) and into NLC (using neurobasal medium supplemented with NGF, B27, glutamine and glutamate). Morphometric analysis of neuron-like cells was performed on microphotographs taken at several time points during the differentiation procedure. ONS cells were adapted to serum deprivation and differentiated into neuronal-like cells (using DMEM/F12 with N2 medium and DMEM/F12 with B27 medium). Our results indicate that we successfully established primary rat cultures from olfactory mucosa stem cells. The efficiency of the isolation/proliferation procedure was confirmed by positive immunostaining with stemness marker nestin and also by their ability to form neurospheres. The morphometric analysis of NLC revealed that we successfully differentiated neurosphere-forming cells into neuron-like cells, since they assume a neuronal like phenotype and they highly express the neuronal marker β-tubulin III. Additionally, ONS cultures were established and further differentiated by gradual serum deprivation. In fact, these cells presented neuronal-like phenotypic characteristics when cultured in defined medium. However, additional experiments for characterization of this new model system should be performed. From our results we can conclude that we efficiently established and characterized new stem cells model systems. These results are of paramount importance since they will be used for the study of cellular and molecular mechanisms underlying several neuropathologies, including Alzheimer’s disease

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Wells, Karen Elizabeth. "Characterisation of the stem/precursor cells of the rat olfactory epithelium". Thesis, University of Cambridge, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.613198.

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Momma, Stefan. "Neural stem cells and their contribution to neurogenesis in the adult mammalian brain /". Stockholm : Karolinska institutet, 2002. http://diss.kib.ki.se/2002/91-7349-324-4/.

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Murdoch, Barbara. "Identification, regulation and lineage tracing of embryonic olfactory progenitors". Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/994.

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Neurogenesis occurs in exclusive regions in the adult nervous system, the subventricular zone and dentate gyrus in the brain, and olfactory epithelium (OE) in the periphery. Cell replacement after death or injury, occurs to varying degrees in neural tissue, and is thought to be dependent upon the biological responses of stem and/or progenitor cells. Despite the progress made to identify adult OE and central nervous system (CNS) progenitors and lineage trace their progeny, our spatial and temporal understanding of embryonic OE neuroglial progenitors has been stalled by the paucity of identifiable genes able to distinguish individual candidate progenitors. In the developing CNS, radial glia serve as both neural progenitors and scaffolding for migrating neuroblasts and are identified by the expression of a select group of antigens, including nestin. Here, I show that the embryonic OE contains a novel radial glial-like progenitor (RGLP) that is not detected in adult OE. RGLPs express the radial glial antigens nestin, GLAST and RC2, but not brain lipid binding protein (BLBP), which, distinct from CNS radial glia, is instead found in olfactory ensheathing cells, a result confirmed using lineage tracing with BLBP-cre mice. Nestin-cre-mediated lineage tracing with three different reporters reveals that only a subpopulation of nestin-expressing RGLPs activate the “CNS-specific” nestin regulatory elements, and produce spatially restricted neurons in the OE and vomeronasal organ. The dorsal-medial restriction of transgene-activating cells is also seen in the embryonic OE of Nestin-GFP transgenic mice, where GFP is found in a subpopulation of GFP+ Mash1+ neuronal progenitors, despite the fact that endogenous nestin expression is found in RGLPs throughout the OE. In vitro, embryonic OE progenitors produce three biologically distinct colony subtypes, that when generated from Nestin-cre/ZEG mice, produce GFP+ neurons, recapitulating their in vivo phenotype, and are enriched for the most neurogenic colony subtype. Neurogenesis in vitro is driven by the proliferation of nestin+ progenitors in response to FGF2. I thus provide evidence for a novel neurogenic precursor, the RGLP of the OE, that can be regulated by FGF2, and provide the first evidence for intrinsic differences in the origin and spatiotemporal potential of distinct progenitors during OE development.

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Patel, Nirmal Praful School of Medicine UNSW. "Olfactory progenitor cell transplantation into the mammalian inner ear". Awarded by:University of New South Wales. School of Medicine, 2006. http://handle.unsw.edu.au/1959.4/26180.

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A practical consideration in the development of cellular therapy technology for the inner ear is the development of an in vitro model for assessing the optimal conditions for successful application of cells. The first part of this thesis describes the adaptation of the cochleovestibular structure harvested from P1 mouse pups for analysis of factors critical for the optimal implantation of stem cells in the inner ear. Results of these studies establish that the c17.2 neural stem cell line can be introduced into the cochleovestibular structure in vitro. Using this model, c17.2 cells demonstrated survival predominantly within the vestibule and basal spiral ganglion regions. Furthermore, the addition of the ototoxin, cisplatin and the neurotrophin, Brain Derived Neurotrophic Growth Factor (BDNF) enhanced the survival and migration/dispersion of c17.2 cells within the cochleovestibular explant. The second part of this thesis examines the hypothesis that olfactory neurosphere (ONS) and progenitor cells harvested from the olfactory epithelium represent a viable source of graft material for potential therapeutic applications in the inner ear. Olfactory epithelium represents a unique source of pluripotent cells that may serve as either homografts or autografts. The feasibility of ONSs to survive and integrate into a mammalian cochlea in vivo was assessed. The ONSs were isolated as a crude fraction from the olfactory epithelium of P1 to P3 day old swiss webster mouse pups, ubiquitously expressing the Green Fluorescent Protein (GFP) marker. The ONSs were microinjected into the cochleae of adult CD1 male mice. Four weeks following their implantation, ONS cells expressing the GFP marker and stained by Nestin were identified in all areas of the cochlea and vestibule, including the spiral ganglion. Robust survival and growth of the implanted ONS and ONS derived cells in the cochlea also included the development of ???tumor-like??? clusters, a phenomenon not observed in control animals implanted with c17.2 neural stem cells. Collectively, the results of this thesis illustrate the potential of olfactory neurosphere and progenitor cells to survive in the inner ear and expose a potential harmful effect of their transplantation.

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Malik, Astha. "Circadian Clocks in Neural Stem Cells and their Modulation of Adult Neurogenesis, Fate Commitment, and Cell Death". Bowling Green State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1434986257.

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Kalincik, Tomas Medical Sciences Faculty of Medicine UNSW. "Disturbances of autonomic functions in spinal cord injury: autonomic dysreflexia and thermoregulation". Publisher:University of New South Wales. Medical Sciences, 2009. http://handle.unsw.edu.au/1959.4/43516.

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Disorders of the autonomic nervous system constitute serious complications of spinal cord injury (SCI) and their treatment is usually highly prioritised by spinal patients. Among these, autonomic dysreflexia and impaired thermoregulation are potentially life threatening conditions and require effective management. Olfactory ensheathing cells (OECs), progenitor cells and polymeric scaffolds have been tested in animal models of SCI and some of them have been considered for clinical trials. However, evaluation of the effect of such interventions on autonomic functions has received only rudimentary attention and would require a more thorough experimental assessment before the methods are utilised in human patients. This thesis tested two potential therapeutic strategies for autonomic dysreflexia and examined disorders of thermoregulatory functions in a rat model of spinal cord transection. Magnitude and duration of autonomic dysreflexia were evaluated with radio telemetry in spinalised animals treated with (i) implants of OECs and olfactory neurosphere-derived cells seeded in poly(lactic co glycolic) porous scaffolds or with (ii) transplants of OECs alone. (iii) Effects of SCI and of OECs on the morphology of sympathetic preganglionic neurons (SPNs; which are involved in pathogenesis of autonomic dysreflexia) stained for NADPH diaphorase were examined. (iv) Doppler ultrasonography and infrared thermography were used to assess responses of tail blood flow and surface temperature to cold. Transplants of OECs alone, but not in combination with olfactory neurosphere-derived cells and polymeric scaffolds, resulted in significantly shortened episodes of autonomic dysreflexia. This may be attributed to the alterations to the morphology of SPNs adjacent to the lesion: a transient increase in the morphometric features of the SPNs was evoked by spinal cord transection and this was further altered by transplantation of OECs. The thesis also showed that local responses of tail blood flow and temperature to cold were not abolished by complete SCI suggesting that temperature homeostasis could still be maintained in response to cold. It is hypothesised that OECs facilitate improved recovery from autonomic dysreflexia through alteration of the morphology of SPNs. Furthermore, it is suggested that the role of the tail in heat conservation can be regulated by mechanisms that are independent of the descendent neural control from supraspinal centres.

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Johnstone, Steven Andrew. "A comparative study of the biological and molecular properties of mesenchymal stem cells isolated from bone marrow and the olfactory system". Thesis, University of Glasgow, 2015. http://theses.gla.ac.uk/6308/.

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Neurodegenerative conditions such as Multiple Sclerosis (MS) and spinal cord injury (SCI) affect hundreds of thousands of people each year worldwide, and numerous cell transplant-based therapeutic strategies are being investigated to aid in the repair and regeneration of the central nervous system. Of particular interest are mesenchymal stem cells (MSCs), due to their differentiation potential, their immunomodulatory effects, and their ability to stimulate various biological properties due to the substantial variety of growth factors, chemokines, and other signalling molecules secreted by these cells. MSCs taken from the bone marrow (BM-MSCs) have demonstrated significant reparative potential in animal models of both MS and SCI. The question I address throughout this thesis however, is whether MSCs from another niche; the olfactory mucosa (OM-MSCs), are a preferable or at least alternative candidate for such therapies, compared to BM-MSCs, and if they are, why are they? Previous studies have shown that OM-MSCs can be purified and grown from human olfactory mucosa and when incubated with rat glial/neuronal co-cultures are capable of increasing axonal myelination, an effect not elicited by BM-MSCs. This potentially has great therapeutic benefit for a range of neurodegenerative conditions, as a significant part of the regenerative process involves replacing the protective myelin membrane which ensheaths axons. A comparative study of the two types of MSCs shows a number of similarities, including the expression of the same panel of MSC markers, a 64% homology in miRNA expression, an ability to differentiate towards bone and fat, and a propensity for bone formation when cultured on osteogenic nanotographies. This thesis also outlines a number of differences between each phenotype which suggest that OM-MSCs could even be a preferred alternative, especially in neuroregenerative therapies. OM-MSCs were shown to express significantly more Nestin than BM-MSCs, and to proliferate at a significantly higher rate, two observations which may be related. This increased proliferation would have enormous benefit for their use, as BM-MSCs are mitotically quite slow, and any MSC-based therapies would require very large numbers of cells. Twenty six different miRNA were shown to be differentially expressed between BM-MSCs and OM-MSCs. Three of these; miR-140-5p, miR-146a-5p, and miR-335-5p were linked to three important biological functions; myelination, cell survival, and cell proliferation respectively. These three biological functions, importantly, are ones which were observed as being behavioural differences between OM-MSCs and BM-MSCs. OM-MSCs were also shown to secrete significantly more of the pro-myelinating chemokine, CXCL12, which was confirmed as being regulated by the microRNA, miR-140-5p. This offered a potential mechanism for the pro-myelinating effect of OM-MSCs, and also opens up new research potential for investigating therapeutic targets to regulate myelination. The data presented in this thesis shows many similarities between BM-MSCs and OM-MSCs, but it also highlights some profound differences which suggest that either they originate from a different lineage entirely, or that the cellular niche that they reside in does indeed affect the differentiation and behaviour of mesenchymal stem cells.

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Kolterud, Åsa. "The Role of Lhx2 During Organogenesis : - Analysis of the Hepatic, Hematopoietic and Olfactory Systems". Doctoral thesis, Umeå universitet, Molekylärbiologi (Teknat- och Medfak), 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-306.

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During embryonic development a variety of tissues and organs such as the lung, eye, and kidney are being formed. The generation of functional organs is regulated by reciprocal cell-cell interactions. Via the secretion of soluble molecules one type of cells affect the fate of their neighboring cells. A central issue in organogenesis is how a cell interprets such extrinsic signals and adopts a specific fate, and how the cell in response to this signal establishes reciprocal signaling. Transcription factors play a critical role in this process and my thesis focuses on the role of the LIM-homeodomain transcription factor, Lhx2, in the development of three different organ systems, the liver, the hematopoietic system and the olfactory system. The liver is formed from endoderm of the ventral foregut and mesenchyme of the septum transversum (st) and its development depends upon signaling interactions between these two tissues. As the liver becomes a distinct organ it is colonized by hematopoietic cells and serves as hematopoietic organ until birth. The fetal liver provides a microenvironment that supports the expansion of the entire hematopoietic system (HS) including the hematopoietic stem cells (HSCs). Liver development in Lhx2-/- embryos is disrupted leading to a lethal anemia due to insufficient support of hematopoiesis. To further investigate the role of Lhx2 in liver development I analyzed gene expression from the Lhx2 locus during liver development in wild-type and Lhx2-/- mice. Lhx2 is expressed in the liver associated st mesenchymal cells that become integrated in the liver and contribute to a subpopulation of hepatic stellate cells in adult liver. Lhx2 is not required for the formation of these mesenchymal cells, suggesting that the phenotype in Lhx2-/- livers is due to the presence of defective mesenchymal cells. The putative role of Lhx2 in the expansion of the HS was examined by introducing Lhx2 cDNA into embryonic stem cells differentiated in vitro. This approach allowed for the generation of immortalized multipotent hematopoietic progenitor cell (HPC) lines that share many characteristics with normal HSCs. The Lhx2-dependent generation of HSC-like cell lines suggests that Lhx2 plays a role in the maintenance and/or expansion of the HS. To isolate genes putatively linked to Lhx2 function, genes differentially expressed in the HPC lines were isolated using a cDNA subtraction approach. This allowed for the identification of a few genes putatively linked to Lhx2 function, as well as several stem cell-specific genes. The antagonist of Wnt signalling, Dickkopf-1 (Dkk-1), was identified in the former group of genes as it showed a similar expression pattern in the fetal liver, as that of Lhx2 and expression of Dkk-1 in fetal liver and in HPC lines appeared to be regulated by Lhx2. This suggests that Dkk-1 plays a role in liver development and/or HSC physiology during embryonic development. During development of the olfactory epithelium (OE) neuronal progenitors differentiate into mature olfactory sensory neurons (OSNs) that are individually specified into over a thousand different subpopulations, each expressing a unique odorant receptor (OR) gene. The expression of Lhx2 in olfactory neurons suggested a potential role for Lhx2 in the development of OSNs. To address this OE from Lhx2-/- and wild-type mice was compared. In the absence of functional Lhx2 neuronal differentiation was arrested prior to onset of OR expression. Lhx2 is thus required for the development of OSN progenitors into functional, individually specified OSNs. Thus, Lhx2 trigger a variety of cellular responses in different organ systems that play important roles in organ development in vivo and stem cell expansion in vitro.

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Chalfouh, Chaima. "Effet de la stimulation magnétique répétitive trans-spinale comme thérapie non invasive dans le cadre des lésions médullaires. The Regenerative Effect of Trans-spinal Magnetic Stimulation After Spinal Cord Injury: Mechanisms and Pathways Underlying the Effect FoxJ1 regulates spinal cord development and is required for the maintenance of spinal cord stem cell potential Inhibition of ADAMTS-4 Expression in Olfactory Ensheathing Cells Enhances Recovery after Transplantation within Spinal Cord Injury Resident neural stem cells guarantee the regeneration promoted by bulbar olfactory ensheathing cell transplantation after spinal cord injury". Thesis, Normandie, 2020. http://www.theses.fr/2020NORMR099.

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Les lésions de la moelle spinale constituent un problème de santé public d’une ampleur grandissante. Bien que l’espérance de vie ait été améliorée, les patients médullo-lésés souffrent de certains handicaps entraînant une perte partielle ou complète des fonctions sensorielles et/ou motrices. La moelle spinale lésée entreprend aussitôt une réponse à cette lésion. Chronologiquement, la lésion se divise en deux grandes phases : la phase primaire qui se caractérise par la destruction tissulaire induite par le traumatisme mécanique, suivie d’une destruction cellulaire. Alors que la phase secondaire est la conséquence moléculaire et cellulaire de la phase primaire. Durant plusieurs années, différentes stratégies thérapeutiques ont été proposé principalement la thérapie cellulaire qui a prouvé ses effets bénéﬁques dans différents modèles expérimentaux de la lésion , mais de nombreux obstacles sont à prendre en considération tel que, principalement, son caractère invasif. aﬁn de pouvoir l’appliquer chez l’homme d’une manière efficace et reproductible . A la vue de ces contraintes cliniques, nous avons décidé d’explorer un traitement non invasif connu pour ses effets neuroprotecteurs et neurotrophiques dans le SNC ; la stimulation magnétique répétitive trans-spinale (rTSMS). Etonnement, peu d’études ont exploré cette thérapie dans le cadre des LMTs, et rare sont celles qui l’ont utilisé d’une manière focale, c’est à dire directement au niveau du site de la lésion. A ce jour, les mécanismes et les voies sous-jacentes de ces effets dans ce cadre restent toujours inconnus. C’est pourquoi nous avons entrepris de caractériser ces effets dans le cadre de mes travaux de Thèse. En effet, en premier lieu, nous avons évalué les effets de la rTSMS sur la réparation tissulaire, via la modulation de la cicatrice médullaire et de ces différentes composantes in vivo, ainsi que sur la récupération fonctionnelle dans différents paradigmes (aigue et chronique) et à différents âges (juvénile, adulte et vieux) chez des souris WT ayant subi une transsection complète de la moelle spinale. En second lieu, l’objectif était de décrire les mécanismes à l’origine des effets de la rTSMS. Pour ce faire, des analyses protéomiques ont été réalisées, puis nous avons évalué l’effet de la rTSMS sur la réactivité des cellules souches endogènes de la moelle, ainsi que, la contribution de ces dernières dans la mise en place de la cicatrice gliale in vitro et in vivo via un modèle de souris transgénique hFoxJ1-CreER T2 ::tdTomato. L’objectif global était d’étudier, pour la première fois, l’effet de la rTSMS sur la réponse des différentes composantes cellulaires résidentes de la moelle spinale, les mécanismes à l’origine de ces effets, ainsi que la capacité à restaurer les fonctions motrices perdues suite à la lésion médullaire
Spinal cord injury (SCI) leads to a loss of sensitive and motor functions. Currently, there is no therapeutic intervention offering a complete recovery. Here, we report that repetitive trans-spinal magnetic stimulation (rTSMS) can be a noninvasive SCI treatment that enhances tissue repair and functional recovery. Several techniques including immunohistochemical, behavioral, cells cultures, and proteomics have been performed. Moreover, different lesion paradigms, such as acute and chronic phase following SCI in wild-type and transgenic animals at different ages (juvenile, adult, and aged), have been used. We demonstrate that rTSMS modulates the lesion scar by decreasing fibrosis and inflammation and increases proliferation of spinal cord stem cells. Our results demonstrate also that rTSMS decreases demyelination, which contributes to axonal regrowth, neuronal survival, and locomotor recovery after SCI. This research provides evidence that rTSMS induces therapeutic effects in a preclinical rodent model and suggests possible translation to clinical application in humans

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Girard, Stephane. "Amnésie et thérapie cellulaire : Etude de l'écotropisme des cellules souches adultes de la lamina propria olfactive". Thesis, Aix-Marseille, 2012. http://www.theses.fr/2012AIXM4759.

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Les faibles capacités régénératives intrinsèques du système nerveux central, après la survenue de lésions traumatiques ou l'apparition de maladies neuro-dégénératives, ont orienté les recherches vers des thérapies basées sur l'utilisation de cellules souches dans le but de régénérer le tissu cérébral. Cependant, des limitations éthiques et techniques associées aux cellules souches embryonnaires, fœtales ou neurales chez l'adulte restreignent leur utilisation en clinique humaine. À la recherche d'une source alternative, nous nous sommes intéressés à des cellules souches adultes peu connues, provenant du chorion d'un tissu nerveux périphérique en perpétuel renouvellement : les cellules souches de la lamina propria olfactive, localisée dans la cavité nasale. Ces cellules multipotentes ont été décrites comme un sous-type de cellules souches mésenchymateuses, présentant de fortes capacités prolifératives et neurogéniques. En utilisant un premier modèle murin d'amnésie induit par lésion excito-toxique des hippocampes, nous avons montré que des cellules souches olfactives humaines, greffées dans les zones lésées ou dans le liquide céphalo-rachidien, i) s'installent et adoptent un phénotype neuronal, ii) rétablissent la circulation d'informations au sein des réseaux neuronaux défectueux et iii) permettent une récupération des capacités d'apprentissage et de mémorisation. Suite à ces résultats très encourageants, le premier objectif de cette thèse a été de mieux faire connaître ces cellules souches adultes auprès de la communauté scientifique
The brain displaying poor regenerative capacities, exogenous stem cell-based therapy has been proposed as an attractive strategy to regenerate cerebral tissue after acute injuries or neurodegenerative disorders. However, ethical and technical issues, associated with embryonic, fetal or adult neural stem cells, limit their use in human medicine. In search of alternative candidates, we focused our attention on adult stem cells, located in a peripheral nervous tissue: the nasal stem cells sited in the olfactory lamina propria. These multipotent stem cells have been characterized as a member of the mesenchymal stem cell superfamily, displaying strong proliferative and neurogenic properties. Recently, using a mouse model of amnesia induced by excito-toxic lesions of hippocampal neurons, we demonstrated that olfactory stem cells, grafted in lesioned areas or into the cerebrospinal fluid, i) migrate and differentiate into neuron-like cells, ii) contribute to the restoration of local neuronal networks and iii) promote recovery of learning and memory abilities. In line with these promising results, the first aim of the current thesis was to promote the use of these adult stem cells by the scientific community. For this purpose, we published an article and a book chapter in which we demonstrated that they are suitable for autologous cell therapy in humans. Using an audiovisual document, we showed that these cells i) can be safely obtained in humans, under local anesthesia, without any loss of smell and ii) are easily and quickly amplifiable in vitro

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Gaborieau, Élodie. "Origine, diversité et contrôle transcriptionnel des interneurones périglomérulaires calrétinines du bulbe olfactif". Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE1307/document.

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Les cellules souches neurales (CSNs) de la zone sous-ventriculaire (ZSV) présentent une activité germinale intense tout au long de la vie d'un individu. Les CSNs postnatales sont régionalisées en microdomaines exprimant des facteurs de transcription spécifiques et générant des sous-types neuronaux distincts dans le bulbe olfactif (BO). Les interneurones calrétinine (CalR+) représentent la plus grande population d'interneurones périglomérulaires (PG) du BO produits après la naissance. Cependant, contrairement à d'autres, il existe peu d'informations concernant leur origine, leur diversité et leur fonction dans le BO, ainsi que les facteurs de transcription impliqués dans leur génération. Des études antérieures ont mis en évidence que les interneurones CalR + PG sont générés à la fois par les microdomaines médial et dorsal de la ZSV, et ont suggéré que le facteur de transcription Sp8 serait impliqué dans leur génération. Ce travail de thèse a eu pour objectif : 1) d'affiner les approches actuelles afin de manipuler l'expression génique dans les CSNs de la ZSV postnatale d'une manière contrôlée temporellement, 2) d'explorer l'origine et la fonction des interneurones CalR + périglomérulaires, 3) d'étudier le rôle du facteur de transcription Sp8 dans le codage transcriptionnel de la spécification des interneurones CalR + périglomérulaires ainsi que leur maturation. Ainsi, une approche d'électroporation postnatale classique a été affinée afin de pouvoir manipuler l'expression des gènes dans les CSNs de la ZSV et ainsi permettre de cartographier le devenir à long terme de la progénie des CSNs et de manipuler génétiquement ces CSNs à une étape précise de leur différentiation. Le perfectionnement de cette approche a permis d'identifier deux sous-populations d'interneurones CalR + présentant des origines spatiales et temporelles différentes après la naissance, ainsi que d'explorer les implications fonctionnelles et morphologiques de cette diversité. Ainsi, une fraction importante et non décrite d'interneurones CalR + PG présente des propriétés de neurones immatures (c'est-à-dire qu'elle reçoit peu d'entrées synaptiques et est faiblement excitable), remettant en question leur rôle dans le traitement de l'information olfactive. Enfin, des manipulations génétiques du facteur de transcription Sp8 à divers stades de la différenciation des interneurones CalR+ ont mis en évidence son rôle dans la survie à long terme des interneurones CalR + PG matures, tout en excluant un rôle dans leur spécification précoce. Ces résultats amène ainsi un éclairage nouveau sur l'origine, la diversité et le codage transcriptionnel des interneurones CalR + PG et appellent à une caractérisation plus précise de leur rôle dans le traitement de l'information olfactive
The subventricular zone (SVZ) is a brain region that shows intense germinal activity throughout postnatal life. The postnatal SVZ is subdivided in microdomains containing neural stem cells (NSCs) that express defined transcription factors and generate distinct neuronal subtypes in the olfactory bulb (OB). Calretinin-expressing (CalR+) interneurons represent the largest population of OB periglomerular interneurons produced after birth. Yet, in contrast to others, limited information exists regarding their origin, diversity and function in the OB, as well as the transcription factors that guide their generation. Previous studies highlighted that CalR+ PG interneurons are generated by both the medial and dorsal SVZ microdomains, and suggested that the transcription factor Sp8 is involved in their generation.This work aimed at 1) refining current approaches for manipulating gene expression in postnatal SVZ NSCs in a temporally controlled manner, 2) exploring the origin and the function of CalR+ periglomerular neurons, 3) investigating the role of Sp8 in the transcriptional coding of CalR+ periglomerular interneurons specification and maturation.Refinement of the classical electroporation approach allowed the long-term fate mapping and timely-controlled genetic manipulation of NSCs of the SVZ. Using this refined approach allowed identifying two subpopulations of CalR+ interneurons that show different spatial and temporal origins after birth, as well as to explore the functional and morphological correlates of this diversity. A large and previously non-described fraction of CalR+ periglomerular interneurons exhibits properties of immature neurons (i.e. little synaptic inputs and weak excitability), questioning their role in olfactory processing. Finally, genetic manipulations of the transcription factor Sp8 at different stages during CalR+ interneuron differentiation highlighted its role in the long-term survival of mature CalR+ periglomerular interneurons, while excluding a role in their early specification. Altogether these results shed new lights on the origin, diversity and transcriptional coding of CalR+ periglomerular i nterneurons and call for a characterization of their role in olfactory processing

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Ould-Yahoui, Adlane. "Le système MMP/TIMP dans la croissance neuritique et la motilité des cellules souches de la muqueuse olfactive". Thesis, Aix-Marseille 2, 2011. http://www.theses.fr/2011AIX20672.

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Les métalloproteases matricielles (MMPs) appartiennent à une famille d'endopéptidases dépendantes du zinc, présentent sous forme secrétée ou membranaire (MT-MMP) et qui jouent un rôle fondamental dans la signalisation cellulaire. L'activité des MMPs est régulée par leur inhibiteurs endogènes, les inhibiteurs tissulaires des MMPs (TIMPs). Le système MMP/TIMP régule les interactions cellule-cellule et cellule-matrice extra cellulaire et module la motilité cellulaire par clivage protéolytique des composants de la matrice extra cellulaire aussi bien lors de processus physiologiques que dans des situations pathologiques.Dans un premier temps, nous avons mis en évidence le rôle de TIMP-1 dans la modulation de la croissance neuritique et la morphologie neuronale, via l'inhibition de MMP-2 et non de MMP-9. souches de la muqueuse olfactive (OE-MSCs). Nous montrons dans cette étude que les gélatinases MMP-2 et MMP-9 ainsi que la MMP membranaire MT1-MMP, sont impliquées dans la migration des OE-MSCs. Nous montrons également que les gélatinases sont probablement impliquées dans les propriétés neurotrophiques des OE-MSCs et des cellules engainantes olfactives.L'ensemble de ces résultats apporte de nouveaux éléments fondamentaux, dans la compréhension du rôle du système MMP/TIMP dans les processus post-lésionnels qui ont lieu au sein du système nerveux central
The matrix metalloproteinases (MMPs) belong to a growing family of Zn2+-dependent endopeptidases, secreted or membrane-bound (MT-MMP), which play a fundamental role in the cell signalling. The activity of the MMPs is regulated by their endogenous inhibitors, the tissue inhibitors of MMPs (TIMPs). The MMP / TIMP system regulates the cell-cell and cell-extracellular matrix interactions and modulates the cellular motility through the cleavage of protein components of the extracellular matrix, as well during physiological and pathological conditions.Our results suggest that TIMP-1 is implicated in the modulation of the neurite outgrowth and morphology of cortical neurons through the inhibition at least in part, of MMP-2 and not MMP-9. Afterward, we study of the system MMP / TIMP in the migration of the stem cells of olfactory ectomesenchymal stem cells (OE-MSCs). We show that gelatinases MMP-2 and MMP-9 as well as MT1-MMP, are involved in OE-MSCs migration. We also show that gelatinases are probably involved in neurotrophic properties of the OE-MSCs and olfactory ensheathing cells.Altogether, these results provide new evidences on the role of MMP/TIMP system in central nervous system post-lesional processes

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Reiter, Allison R. "Role of dietary zinc deficiency in adult neuronal stem cell proliferation in the olfactory bulb". Tallahassee, Fla. : Florida State University, 2008. http://purl.fcla.edu/fsu/lib/digcoll/undergraduate/honors-theses/341805.

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Thesis (Honors paper)--Florida State University, 2008.
Advisor: Cathy W. Levenson, PhD., Florida State University, College of Human Sciences, Dept. of Nutrition, Food and Exercise Sciences. Includes bibliographical references.

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Oliver, Joe, Cuihong Phd Jia i Theodoor Phd Hagg. "Inhibition of focal adhesion kinase promotes adult olfactory stem cell self-renewal and neuroregeneration via ciliary neurotrophic factor". Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/asrf/2018/schedule/97.

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The Olfactory Epithelium (OE) is a specialized epithelial tissue inside the nasal cavity that is involved in the smell sensation. The OE maintains neuroregeneration, i.e. producing new olfactory sensory neurons, throughout the adult life via neural stem cell self-renewal, proliferation, neuronal differentiation and maturation. The neural stem cell niche regulates stem cell self-renewal and proliferation, and consists of stem cells, blood vessels and multiple extracellular matrix proteins (ECMs). ECMs regulate stem cell adhesion, proliferation, differentiation and migration via integrins. One of the main mediators of intracellular integrin signaling is the Focal Adhesion Kinase (FAK). Our previous studies found that FAK inhibition increased cell proliferation in adult mouse olfactory epithelium (OE) via up-regulation of Ciliary Neurotrophic Factor (CNTF). Now we continue to test whether FAK inhibition increases neuroregeneration through CNTF in the adult mouse OE using BrdU-chase pulse method. Adult male and female C57BL/6, CNTF wildtype and CNTF knockout (lack the CNTF gene) mice were systemically injected with PBS or FAK inhibitor (FAK14) for 3 days. During these 3 days, BrdU was injected into mice 4 h following PBS or FAK on each day. BrdU acts as a thymidine analog and is incorporated into DNA during DNA syntheses. Using immunohistochemistry with anti-BrdU antibody, BrdU+ cells can be visualized in the tissue. The BrdU+ cells are the ones who are replicating during the time frame when BrdU was given. 20 days after last BrdU injection, we fixed the mice via cardiac perfusion. The whole heads of mice was decalcified with EDTA and then frozen cross head sections including OE were cut using cryostat and mounted onto slides. The OE sections were then stained with anti-BrdU antibody followed by FITC-conjugated secondary antibody. The BrdU+ cells in the OE were counted in three sections (both left and right sides) per mouse and normalized to linear length of OE basement membrane. The results of the experiment showed that FAK 14 significantly increased BrdU+ stem cells and olfactory sensory neurons in the OE of C57BL/6 and CNTF wildtype mice but not knockout mice, indicating that FAK inhibition promotes olfactory stem cell self-renewal and neuroregeneration via CNTF. Collectively, this data indicates that FAK normally inhibits OE neuroregeneration by inhibiting CNTF expression and identifies the OE is a good model to study neuroregenerative mechanisms in the CNS.

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Hawkins, Sara Joy. "The timing of regeneration in the amphibian olfactory system". Master's thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/15444.

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Mestrado em Biologia Molecular e Celular
Comprehending the mechanisms that make lifelong neurogenesis possible has a clear interest for the better understanding of the basic principles that govern cellular and molecular interactions in the nervous system, as well as a relevant clinical interest. The limited ability of the central nervous system to generate new neurons in order to replace those that have been lost is a formidable obstacle to recovery from neuronal damage caused by injury or neurodegenerative disease. The olfactory system (OS) is an ideal system to study the process of neuronal recovery after injury, as it is known for its lifelong capacity to replenish cells lost during natural turnover, as well as its remarkable ability to regenerate after severe lesion. The olfactory epithelium (OE) shows neurogenesis throughout life. Newly differentiated olfactory receptor neurons (ORNs) are continuously reintegrated into an existing circuitry to maintain the sense of smell. The aim of this thesis is to describe the morphological and functional alterations that occur over time in the OS of larval Xenopus laevis, after transection of the olfactory nerve (ON). Results obtained using immunohistochemistry essays, as well as sensory neuron labeling and calcium imaging techniques, indicate that ORN cell death reaches its peak 48 hours after transection, and that proliferating stem cells found in the basal cell layer of the OE are quickly upregulated after lesion. Supporting cells seem to maintain both morphological and functional integrity after transection of the ON. The OE recovers its original morphological structure 1 week after transection, at which time the first axons reach the olfactory bulb (OB) and begin the process of reinnervation. Spontaneous activity of mitral/tufted cells occurs in the OB during the first weeks after transection but no odor-induced activity is observed. After 3-4 weeks glomerular responses were observed in some animals upon application of stimulus, but the response and glomerular morphology are clearly altered as compared to control. After 6-7 weeks responses seem to have fully recovered, indicating that the OS of larval X. laevis recovers morphologically and functionally 6-7 weeks after ON transection.
O estudo dos mecanismos responsáveis pela neuro-regeneração tem um marcado interesse para a compreensão dos princípios básicos que governam as interações celulares e moleculares no sistema nervoso, bem como um interesse clínico relevante. A limitada capacidade do sistema nervoso central para dar origem a novos neurónios é um obstáculo formidável para a recuperação do sistema após lesão neuronal ou doença neurodegenerativa. O sistema olfativo é um sistema ideal para o estudo do processo de recuperação após lesão neuronal, pois é conhecido no mundo científico pela sua capacidade contínua e vitalícia para repor células perdidas durante a renovação celular natural, bem como a sua notável capacidade para regenerar após uma lesão grave. O epitélio olfativo apresenta a capacidade para dar origem a novos neurónios ao longo de toda a vida. Neurónios sensoriais olfativos diferenciados são continuamente reintegrados num circuito já existente, mantendo assim o sentido do olfato. O objetivo desta tese é descrever as alterações morfológicas e funcionais que ocorrem ao longo do tempo no sistema olfativo de Xenopus laevis em estado larvar, após o corte do nervo olfativo. Os resultados obtidos através do uso de ensaios de imunohistoquímica, bem como técnicas de marcação neuronal sensorial e de imagiologia de cálcio, indicam que a morte celular na população de neurónios sensoriais olfativos atinge o seu máximo 48 horas após a lesão, e que células estaminais encontradas na camada basal do epitélio olfativo são positivamente reguladas após lesão e proliferam rapidamente. Células de suporte parecem manter tanto a integridade morfológica como funcional após o corte do nervo olfativo. O epitélio olfativo recupera a sua estrutura morfológica inicial 1 semana após a lesão, momento em que os primeiros axónios atingem o bolbo olfativo e começam o processo de reintegração. Ocorre atividade espontânea das células mitrais/tufados do bolbo olfativo durante as primeiras semanas após a lesão, mas nenhuma atividade induzida por estímulo com odor foi observada. Depois de 3-4 semanas, atividade glomerular foi observada em alguns animais após a aplicação de estímulos, mas a resposta e morfologia glomerular foram claramente alteradas em relação ao controlo. Depois de 6-7 semanas as respostas parecem ter recuperado totalmente, indicando que o sistema olfativo de X. laevis em estado larvar recupera morfológica e funcionalmente 6-7 semanas após o corte do nervo olfativo.

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Orechio, Dailiany. "Caracterização morfológica e celular da zona subventricular e da corrente rostral migratória em encéfalos de fetos caninos". Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/10/10132/tde-29092016-112302/.

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Precursores neurais originados na zona subventricular (ZSV) de algumas espécies animais possuem uma rota de migração neuronal destinada ao bulbo olfatório principal (BOP), onde os neuroblastos migrantes se diferenciam em interneurônios. Esta corrente migratória é mantida na idade adulta. A compreensão de como se organiza na idade fetal é essencial para a compreensão geral e estabelecimento de novas terapias celulares. O objetivo deste estudo é caracterizar a composição celular e organização morfológica da ZSV e da corrente rostral migratória (CRM) em encéfalos de fetos caninos. A ZSV, CRM e BOP foram obtidos de fetos caninos de aproximadamente 57 dias de idade gestacional. O tecido foi analisado através de coloração de Nissl, método de imunohistoquímica de dupla marcação com duplacortina (DCX), fator de transcrição SOX2, proteína glial fibrilar ácida (GFAP), calbindina (CALB), calretinina (CALR) e tirosina-hidroxilase (TH). Foram feitas a análise relativa da expressão da imunorreatividade e análise quantitativa de colocalização celular, além do método de microscopia eletrônica de transmissão. Os resultados mostram que a ZSV dorsal possui células imunorreativas (ir) para o DCX ao longo da parede ventricular, dispostas tangencialmente e fileiras de células SOX2-ir foram encontradas na mesma orientação. A imunorreatividade de GFAP foi mais forte na ZSV dorsal e as células possuem fibras dirigidas tangencialmente adjacentes ao ventrículo lateral e fibras orientadas radialmente em direção ao córtex. A CRM de feto de cão tem início na ZSV anterior e segue caudalmente ao redor da cabeça do núcleo caudado e desce na vertical até se curvar rostralmente em direção ao BOP onde termina na camada de células granulares (CCG). A CRM tem aparência homogênea e densa e possui células positivas para o DCX nas porções iniciais e para SOX2 e GFAP por toda a extensão. Não houve células positivas para CALB, CALR e TH em nenhuma região da ZSV e CRM. No BOP, os resultados mostraram que a camada glomerular (CG) possui células imunorreativas a CALR, TH, SOX2 e GFAP. Na camada plexiforme externa (CPE) houve células imunorreativas a CALB, CALR, SOX2 e GFAP e na CCG, houve células imunorreativas a CALR, SOX2 e GFAP. Na análise de colocalização, foram encontrados na CG neurônios CALR que colocalizam com células SOX2 e uma baixa colocalização de neurônios TH e células SOX2. Na CPE, foi observado um baixo número de colocalização de neurônios CALR e CALB e na CCG, as células SOX2 colocalizam com os neurônios CALR. As conclusões mostram que o feto de cão possui uma CRM em direção BOP, com imunorreatividade celular para DCX, SOX2 e GFAP na ZSV e CRM e para CALB, CALR, TH, SOX2 e GFAP nas principais camadas do BOP
Neural precursors originated in the subventricular zone (SVZ) of some animal species have a migration route destined for main olfactory bulb (MOB), where migrants neuroblasts differentiate into olfactory interneurons. This migratory stream is maintained in adulthood. Understanding how it is organized in fetal age is essential for general understanding and establishment of new cell therapies. The aim of this study is characterize the cellular composition and morphological organization of the SVZ and rostral migratory stream (RMS) of brains of canine fetuses. The SVZ, RMS and MOB was obtained from canine fetuses of the approximately 57 gestacional days-old. The tissue was analyzed by Nissl staining and by immunohistochemical methods for double labelling with doublecortin (DCX), transcription factor SOX2, glial fibrillary acid protein (GFAP), calbindin (CALB), calretinin (CALR) and tyrosinehydroxylase (TH). Semiquantitative analysis of immunoreactivity and quantitative analysis of colocalization were realized, besides ultrastructural analysis by electron microscopy. The results show that in dorsal SVZ, DCX immunoreactive cells were found along the ventricular wall, arranged tangentially and lines of SOX2 cells were also found in the same orientation. The GFAP immunostaining is stronger in dorsal SVZ with tangentially directed fibers near the lateral ventricle and radially oriented fibers toward the cortex. The RMS of dog fetus begins at anterior SVZ and follows caudally around the head of the caudate nucleus and vertically descends to bend rostrally into the MOB, where it ends in the granular cell layer (GCL).The RMS have SOX2 positive cells on entire length, showing a homogeneous appearance and high cell density. There is no positive CALB cells or CALR in any region of the SVZ and RMS. The results of the MOB show that the glomerular layer (GL) there were cells immunoreactive to CALR, TH, SOX2 and GFAP. In the external plexiforme layer (EPL) there were immunoreactive cells for CALR, CALB, SOX2 and GFAP and, the GCL, the prevalence is higher for CALR neurons, SOX2-ir and GFAP-ir cells. In colocalization analysis, they were found a some CALR positive neurons in GL that colabeled with SOX2 cells and a low colocalization of TH neurons and SOX2 cells. In EPL, was observed a low colocalization number of CALR and CALB neurons and in GCL, SOX2 cells colabeled with CALR neurons. The conclusions show that the dog fetus has a RMS directed to the MOB, with cellular immunoreactivity for DCX, SOX2 and GFAP in the ZSV and RMS and cellular immunoreactivity for SOX2 CALB, CALR, TH and GFAP in main olfactory bulb layers

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Rodrigues, Marcio Nogueira. "Avaliação do transplante de células tronco do epitélio olfatório de ratos em coelhos da raça Nova Zelândia submetidos a trauma medular". Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/10/10132/tde-15032012-085251/.

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As células-tronco do epitélio olfatório possuem a capacidade de diferenciação, regeneração de neurônios olfatórios e atuam no processo de mielinização das fibras nervosas. O objetivo desse trabalho foi verificar o potencial terapêutico de células-tronco do epitélio olfatório de ratos Wistar em terapia celular em coelhos submetidos à lesão medular. Foram utilizados ratos com idade de 2 meses e coelhos da raça nova Zelândia obtidos no Biotério do Departamento de Patologia da Faculdade de Medicina Veterinária e Zootecnia da Universidade de São Paulo. Os fragmentos do epitélio olfatório dos ratos foram tratados e colocadas em cultivo em DMEM-F12 suplementado. Foram testadas nos coelhos nova Zelândia 4 tipos de lesão medular, hemisecção dorsal e ventral e secção lateral e total. Foi realizado teste de potencial teratogênico em camundongos NUDE e para terapia foram transplantadas 5x105 células em 4 coelhos submetidos a lesão medular ventral. A morfologia predominante das células em cultivo era fibroblastóide. Os ensaios de curva de crescimento e tendência a formação de colônia demonstraram que as condições de cultivo destas células estavam adequadas. Foi encontrada positividade para Vimentina, Oct-4, GFAP, OMP, Nanog, Citoqueratina-18 e Beta tubulina em imunofluorescência. Em citometria de fluxo foi encontrada negatividade para CD 113, CD 117 e Stro-1 e positividade para Vimentina, Nanog e OMP. Em análise por imunohistoquíca verificou-se marcação positiva para Vimentina, OMP, GFAP e Nanog. Verificou-se marcação positiva no material coletado por retrovírus GFP. Houve melhora clínica nos animais avaliados 21 dias após o transplante de células com retorno de alguns reflexos como o de propriocepção consciente e colocação tátil, o mesmo apresentou ainda reflexo de pedalagem. Conclui-se que o melhor modelo para indução da lesão medular em coelhos é a hemisecção ventral da medula e que as células-tronco olfatórias de ratos Wistar possuem grande potencial terapêutico em animais submetidos à lesão medular.
Stem cells from olfactory epithelium are capable of differentiation, regeneration of olfactory neurons and act in the myelination process of nerve fibers. The aim of this study was to verify the therapeutic potential of stem cells from the olfactory epithelium of Wistar rats in cell therapy in rabbits subjected to spinal cord injury. Rats were aged 2 months and New Zealand rabbits obtained in the bioterio of the Animal Pathology Department, Faculty of Veterinary Medicine, at University of Sao Paulo. Samples of the olfactory epithelium of rats were treated and placed in culture in DMEM-F12 supplemented. Four types of spinal cord injury were tested in New Zealand rabbits: hemisecction dorsal and ventral, total and lateral section. The teratogenic potential test was made in NUDE mices. For therapy were transplanted 5x105 cells in 4 rabbits subjected to spinal cord injury in the ventral region. The cells showed predominant fibroblastoid morphology. Tests for growth curve and colony formation demonstrated that culture conditions in these cells were suitable for the development of these cells. In the immunofluorescence analyses the cells showed positive reaction for vimentin, Oct-4, GFAP, OMP, Nanog, cytokeratin-18 and beta tubulin. In flow cytometry analyses was found negative reaction for CD 113, CD 117 and Stro-1 and positive reaction for vimentin, Nanog and OMP. In immunohistochemistry analysis were observed positive reaction for vimentin, OMP, GFAP and Nanog. Positive labeling was showed on the collected material for GFP. Clinical improvement occurred in the animals evaluated 21 days after cell transplantation. With some reflections about how the placement of conscious proprioception and tactile, it also presented a reflection of pedaling. After this, we concluded that the better model for induction of spinal cord injury in rabbits is the hemisecction ventral and the olfactory stem cells of Wistar rats showed a great therapeutic potential in animals subjected to spinal cord injury.

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De, las Heras Rachel, i n/a. "Neuronal Differentiation: A Study Into Differential Gene Expression". Griffith University. School of Biomolecular and Biomedical Science, 2003. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20040225.161725.

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Neuronal differentiation encompasses an elaborate developmental program which until recently was difficult to study in vitro. The advent of several cell lines able to differentiate in culture proved to be the turning point for gaining an understanding of molecular neuroscience. In particular the olfactory epithelium provides an attractive tool with which to investigate fundamental questions relating to neuronal differentiation, as it displays a unique capacity to regenerate and to retain a neurogenetic potential from its genesis and throughout adult life. The coordinated regulation of gene expression is fundamental to the control of neuronal differentiation. In order to reveal active processes at the molecular level and to dissect key components of molecular pathways, differential gene expression studies provide a foundation for the elucidation of dynamic molecular mechanisms. This thesis identified genes involved in neuronal differentiation by utilising a clonal olfactory receptor neuronal cell line (OLF442). Gene expression levels were identified using differential display and oligonucleotide array technology before and after serum deprivation. Differential display revealed two kinases whose expression levels were elevated during the differentiation of OLF442, identified as focal adhesion kinase (FAK) related non-kinase (FRNK) and mammalian ste20 like (MST)2 kinase. Furthermore, analysis of the oligonucleotide array data confirmed the expression of genes involved in altering presentation of extracellular matrix molecules, in mediating cytoskeletal rearrangements, and in ceasing the cell cycle, supporting the use of OLF442 as a model for studying differentiation. The differentiation of OLF442 results from the synchronisation of multiple transduction cascades and cellular responses as evidenced by the microarray data. A protein that can synchronise such signalling is the non-receptor protein tyrosine kinase, FAK. Thus the finding of the endogenous FAK inhibitor FRNK by differential display was intriguing as there was no difference in the expression level of FAK induced by differentiation, contrasting that of FRNK. This induced FRNK expression was derived autonomously as it was not responsive to the caspase-3 inhibitor, DEVD-CHO. This is particularly pertinent since the primary role of FRNK is to act as an inhibitor of FAK by competing with its substrates and reducing the phosphorylation of both FAK and its associated proteins. Differential display also revealed the upregulation of another kinase, which had 90% homology with rat MST2 kinase within the 3' UTR. Both mouse MST2 kinase (sequence submitted to GenBank, accession number AY058922) and the closely related family member MST1 kinase were sequenced and cloned. Moreover, evidence to support an autonomously expressed carboxyl-terminal domain of MST2 kinase is presented in Chapter 3 and provides a unique way in which MST2 may regulate its own activity. To further understand the role of MST in neuronal differentiation, a series of stable OLF442 transfections (with mutant and wild-type MST constructs) were carried out. MST was localised with cytoplasmic structures that may represent actin stress fibres, indicating a potential cytoskeletal role during neuronal differentiation. This indicated that MST1 may play a role in the morphological processes involved in neuronal differentiation. The identification of two kinases by differential display provided the motivation to understand the cellular context of OLF442 and to determine the phosphorylation status of the mitogen-activated protein kinase (MAPK) signalling cascades. Differentiation of OLF442 induced high-level phosphorylation of a putative B-Raf isoform, MEK2 and ERK1/2. Interestingly, there was a switch between preferential phosphorylation of MEK1 in undifferentiated OLF442 to preferential phosphorylation of MEK2 following differentiation. SAPK/JNK was also phosphorylated, as was the transcription factor c-Jun, which is a common substrate of both the ERK and SAPK/JNK signalling modules. The mapping of the cellular context of differentiating OLF442 has identified a promising model of a novel MAPK module. This consists of FAK signalling through Rap1 to ERK providing sustained activation, which is buffered or terminated by the expression of the endogenous FAK inhibitor FRNK. Furthermore, MST kinase could potentially play a role in regulating the cytoskeletal re-arrangements that are necessary for neuronal differentiation. MST kinase may signal transiently via the SAPK pathway to provide concomitant activation of c-Jun that is required for neuronal differentiation. An understanding of the gene expression pattern of the normal neuronal differentiation program allows a greater understanding of potential developmental aberrations. This could provide an opportunity for therapies to be conceived, while understanding the complexity of neuronal determination could also provide opportunities for stem cell transplantation.

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Honoré, Axel. "Effet des Cellules Gliales Olfactives issues des Bulbes Olfactifs sur les cellules souches épendymaires et leur progénie après une lésion médullaire". Thesis, Normandie, 2017. http://www.theses.fr/2017NORMR060/document.

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Les lésions médullaires traumatiques (LMT) conduisent à une atteinte des voies nerveuses sensitives et motrices. Leur taux de mortalité reste très élevé, d'où la nécessité de trouver de nouveaux traitements. Les Cellules Gliales Olfactives (CGOs) représentent un candidat intéressant de par leur fonction au sein du système olfactif primaire. La découverte d'une population de cellule souche neurale bordant le canal central de la moelle spinale (MS) adulte, appelées cellules épendymaires, suscite un nouvel espoir dans le domaine des biothérapies. Ce travail de thèse a permis d'étudier l'effet d'une transplantation de CGOs sue le comportement des cellules résidentes de la moelle spinale et notamment les cellules souches épendymaires qui, en association avec les astrocytes et les péricytes, participent aux mécanismes de guérison des LMT. L'utilisation du modèle murin hFoxJ1-CreERT2::YFP (permettant le suivi spécifique des cellules épendymaires et de leur progénie), a montré que les CGOs augmentaient in vitro le potentiel d'auto-renouvellement des cellules souches de la MS et modifiaient leur voie de différenciation vers un type neural. In vivo, la transplantation de CGOs augmente la prolifération des cellules épendymaires ainsi que leur différenciation en astrocytes hypo-réactifs conduisant à la formation d'un environnement post-lésionnel bénéfique à la survie neuronal et l'établissement d'une neurogenèse. Nos travaux ont montré pour la première fois que la transplantation de CGOs après LMT permettait la génération de nouveaux neurones. Ceci constitue un nouvel espoir dans l'établissement de stratégies thérapeutiques pour le traitement des LMT chez l'Homme
The spinal cord injuries (SCI) lead to the damages of the spinal cord or nerves and often cause permanent changes in body functions leading to the death. Cell therapies have raised great hope for regenerative medicine. Clinical data showed that the olfactory ensheathing cells (OECs) enhanced functional recovery after SCI and could be a very attractive therapeutic approach. Moreover, the discovery of a new endogenous resident stem cell population, lining the central canal of the spinal cord, named ependymal stem cells, represents a new hope for the therapy. This thesis analyzed the role of OECs transplantation, on the behaviour of ependymal stem cells since these cells, together with astrocytes and pericytes significantly contribute to the recovery of SCI. The use of the mouse model hFoxJ1-CreERT2::YFP (allowing to specifically follow the ependymal stem cells ant their progeny) showed that OECs increased in vitro the self-renewal potential of spinal cord stem cells and modified their differentiation pathway towards a neural type. In vivo, OECs transplantation significantly increases the proliferation of ependymal cells and their differenciation into hypo-reactive astrocytes leading to the formation of a beneficial environment to neuronal survival and the neurogenesis establishment. Our results also showed for the first time that OECs transplantation after SCI allows the generation of new neurons by non-ependymal cell-derived progenitors. These results represent a new hope in the establishment of therapeutic strategies for the treatment of SCI in humans

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Boone, Nathalie. "Les cellules souches olfactives humaines : un nouveau modèle d'étude des mécanismes à l'origine d'une maladie neurodégénérative, la dysautonomie familiale". Thesis, Aix-Marseille 2, 2011. http://www.theses.fr/2011AIX20694.

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La dysautonomie familiale (FD) est une neuropathie héréditaire provoquée par des mutations au sein du gène IKBKAP, la plus commune d'entre elles induisant un épissage alternatif de l'exon 20 au sein de du pré-ARNm de façon tissu-spécifique. L'épissage aberrant est particulièrement prononcé dans les tissus nerveux, conduisant à la dégénerescence progressive des neurones sensoriels et autonomes. La spécificité de la perte des cellules nerveuses dans la FD est mal comprise, par manque d'un modèle approprié. Afin de mieux comprendre les mécanismes moléculaires de l'épissage des ARNm d'IKBKAP, nous avons utilisé un modèle original : les cellules souches olfactives ecto-mesenchymateuses (hOE-MSC) de patients FD. Les hOE-MSC sont pluripotentes et ont la capacité de se différencier en diverses lignées cellulaires, y compris les neurones et les cellules gliales.Nous avons confirmé la présence du transcrit exempt de l'exon 20 d'IKBKAP dans les hOE-MSC de FD et nous avons observé une expression significativement inférieure de la somme des transcrits IKBKAP chez ces patients, du fait de la dégradation d'une partie des isoforme aberrants. Cette réduction est correlée avec une réduction d'expression de la protéine traduite à partir du transcrit d’IKBKAP possèdant l’exon 20, IKAP/hELP1. Nous avons localisé IKAP/hELP1 dans différents compartiments cellulaires, y compris le noyau, ce qui soutient des rôles multiples de cette protéine. Nous avons confirmé que la kinétine, une cytokinine, améliorait le taux de transcrit incluant l'exon 20 et rétablissait des niveaux normaux d'IKAP/hELP1 dans les hOE-MSC de FD. Par ailleurs, nous avons pu modifier le rapport d'épissage d'IKBKAP en augmentant ou en réduisant le ratio WT (inclusion de l'exon 20) : MU (saut de l'exon 20) respectivement, en produisant des sphères flottantes, ou en engageant les cellules vers une différentiation neurale. Les sphères et les cellules différenciées ont été étudiées au niveau pan-génomique, ce qui a permis d'identifier le développement du système nerveux comme étant le processus le plus affecté chez les FD. De plus, nous soulignons le rôle de la kinétine comme un probable régulateur de facteurs d'épissage contribuant à la restauration d'un épissage correct d'IKBKAP.Les hOE-MSC isolées de patients FD représentent une nouvelle approche pour modéliser la pathologie et mieux comprendre l'expression génétique et les approches thérapeutiques possibles de la FD. En outre, elles offrent une application originale à la compréhension d'autres maladies génétiques neurologiques
Familial dysautonomia (FD) is a hereditary neuropathy caused by mutations in the IKBKAP gene, the most common of which results in variable tissue-specific mRNA splicing with skipping of exon 20. Defective splicing is especially severe in nervous tissue, leading to incomplete development and progressive degeneration of sensory and autonomic neurons. The specificity of neuron loss in FD is poorly understood due to the lack of an appropriate model system. To better understand and modelize the molecular mechanisms of IKBKAP mRNA splicing, we collected human olfactory ecto-mesenchymal stem cells (hOE-MSCs) from FD patients. hOE-MSCs have a pluripotent ability to differentiate into various cell lineages, including neurons and glial cells.We confirmed IKBKAP mRNA alternative splicing in FD hOE-MSCs and observed a significant lower expression of both IKBKAP transcripts and IKAP/hELP1 protein in FD cells resulting from the degradation of the transcript isoform skipping exon 20. We localized IKAP/hELP1 in different cell compartments, including the nucleus, which supports multiple roles for that protein. Moreover, we showed that kinetin improved exon 20 inclusion and restores a normal level of IKAP/hELP1 in FD hOE-MSCs. Furthermore, we were able to modify the IKBKAP splicing ratio in FD hOE-MSCs, increasing or reducing the WT (exon 20 inclusion):MU (exon 20 skipping) ratio respectively, either by producing free-floating spheres, or by inducing cells into neural differentiation. Spheres forming cells and lineage neuroglial progenitors were investigated at the genome-wide level, and we confirmed that nervous system development was the most altered process in FD. More, we highlight kinetin role as a putative regulator of splicing factors which contribute to restore a correct splicing of IKBKAP.hOE-MSCs isolated from FD patients represent a new approach for modeling FD to better understand genetic expression and possible therapeutic approaches. This model could also be applied to other neurological genetic diseases

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Ilha, Jocemar. "Reabilitação e plasticidade neuromuscular após lesão medular : efeitos do treino de marcha em esteira e transplante de glia embainhante olfatória". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2011. http://hdl.handle.net/10183/31789.

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O objetivo desta Tese foi analisar os efeitos do treino de marcha isolado e em combinação com transplante de glia embainhante olfatória (GEO) na recuperação funcional e na plasticidade neuromuscular dependente da atividade em um modelo experimental de paraplegia. Para tanto, foram realizados 2 experimentos. No 1º experimento foi realizada completa transecção da medula espinal (TME) em ratos Wistar adultos e após 5 dias iniciou-se um protocolo de 9 semanas de treino de marcha em esteira com suporte de peso corporal. No 2º experimento, os animais receberam, imediatamente após a TME, transplante de células gliais embainhantes olfatórias (GEO) e, como no primeiro experimento, iniciaram o treino de marcha 5 dias após a lesão/transplante. Durante o período dos experimentos, estudos comportamentais para acompanhamento da recuperação da função sensório-motora dos animais foram periodicamente realizados. Além disso, ao término da fase de treinamento (10 semanas após a lesão/transplante), análises histológicas e bioquímicas foram realizadas em amostras de tecido retiradas da medula espinal e músculo sóleo. Os resultados mostram que o treino de marcha em esteira promove melhora da função sensório-motora nos membros posteriores (MPs) de ratos com completa transecção da medula espinal (TME). Os animais treinados apresentaram escores mais altos na escala BBB e normalização do reflexo flexor de retirada. Além disso, os animais com TME apresentaram atrofia do soma celular nos motoneurônios alfa, redução na expressão de sinaptofisina e na atividade da Na+,K+-ATPase na região lombar. Os animais treinados mostraram soma motoneuronal, expressão de sinaptofisina e atividade da bomba de Na+,K+-ATPase similares aos controles. No músculo sóleo, a TME causou severa atrofia muscular, que foi acompanhada pela redução na expressão do fator neurotrófico derivado do encéfalo (BDNF) neste músculo. Por outro lado, o treino de marcha foi capaz de parcialmente impedir/reverter a atrofia provocada pela paralisia muscular e promover um significante aumento na expressão do BDNF, o qual teve positiva correlação com o trofismo muscular dependente da atividade motora no músculo sóleo. O transplante de glia embainhante olfatória (GEO) promoveu significativo aumento nos escores da escala BBB nos animais com completa TME. Entretanto, o treino de marcha foi capaz de acelerar este ganho funcional. Apesar de não ser observada significativa regeneração axonal através do local da lesão, sugerindo que as melhoras funcionais ocorreram independentemente da existência de regeneração axonal. Estes resultados sugerem que o treino de marcha após a TME promove plasticidade morfológica e bioquímica dependente da atividade nos tecidos neuromusculares. A melhora funcional ocorreu concomitantemente a estas alterações plásticas. Além disso, a terapia de transplante de GEO mostrou resultados positivos na recuperação da função motora dos MPs que foi acelerada pelo treino de marcha, mesmo na ausência de regeneração axonal através da lesão. Estes dados mostram importantes informações neurobiológicas que fornecem base neurocientífica para o uso seguro e eficaz destas terapias na reabilitação após LME.
The aim of this thesis was to study the effects of treadmill step training alone and in combination with olfactory ensheathing cells (OEC) on functional recovery and activity-dependent neuromuscular plasticity in a traumatic paraplegia model. For this, we made two experiments. In the 1st experiment, complete spinal cord transection (SCT) was made in adult Wistar rats and after 5 days the spinal animals were underwent a 9 week body-weight-supported treadmill training (BWSTT) program. In the 2nd experiment, the spinal animals received acute olfactory ensheathing cell (OEC) transplantation and, similar to the 1st experiment, started a BWSTT 5 days after the injury/transplantation. Behavioral tests were periodically performed in order to study the hindlimb sensorimotor functions in both experiments. Furthermore, after 9 weeks of the training (10 weeks after SCI/transplantation), histological and biochemical analysis were performed in spinal cord and soleus muscle tissues. The results show that treadmill step training improves hindlimb sensorimotor function in rats with complete spinal cord transection (SCT). The trained animals showed higher BBB scores and normalization of the withdrawal reflex. Furthermore, spinal animals showed alpha motoneuron soma size atrophy, decrease in synaptophysin expression and Na+,K+-ATPase activity in lumbar spinal cord. Trained SCT animals showed motoneuron soma size, synaptophysin expression and Na+,K+-ATPase activity values similar to controls. In soleus muscle, SCT led to severe muscular atrophy, which was accompanied by a decrease in brain-derived neurotrophic factor (BDNF) expression in this muscle. On the other hand, treadmill step training was able to revert/prevent this paralysis-induced muscular atrophy and promote significant improvement in soleus BDNF expression, which was positively correlated to activity-dependent muscular trophism. Olfactory ensheathing cell (OEC) transplantation promotes significant improvements in the BBB scores of animals with SCT. However, treadmill step training was able to accelerate this functional gain. There was no significant axonal regeneration that traversed the injury site, which suggests that functional gains occurred in a manner independent of axonal regeneration. Taken as a whole, these results suggest that treadmill step training after SCT promotes activity-dependent morphological and biochemical plasticity in neuromuscular tissues. The functional improvements occurred concomitantly to these plastic changes. Moreover, OEC therapy showed positive results on hindlimb motor function recovery which was accelerated with treadmill step training even in the absence of axonal regeneration across the lesion site. These results represent important neurobiological information for the neuroscientific basis that supports these therapies as an efficient and safe approach in spinal cord injury rehabilitation.

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Pin-Hui i 呂品慧. "Mesenchymal Stem Cells from Rat Olfactory Bulbs can Differentiate into Cells with Cardiomyocyte Characteristics". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/42482586962570576236.

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碩士
中山醫學大學
醫學研究所
100
Mesenchymal stromal/stem cells (MSCs) are widely distributed in different tissues such as bone marrow, adipose tissues, peripheral blood, umbilical cord and amnionic fluid. Recently, MSC-like cells also exist in rat olfactory bulb and are capable to induce differentiate into mesenchymal lineages: osteocytes, chondrocytes and adipocytes. In vitro and in vivo studies have shown that MSCs derived from bone marrow and adipose tissue are capable of differentiate into cardiomyocytes; however, whether these cells can differentiate into myocardial cells is not known. In this study, we examined whether olfactory bulb derived MSCs could differentiate into myocardial cells in vitro. Fibroblast-like cells isolated from the olfactory bulb of neonatal rats were grown under 4 conditions: no treatment; in the presence of growth factors (neuregulin-1, b-FGF, and forskolin); co-cultured with cardiomyocytes; co-cultured with cardiomyocytes plus neuregulin-1, b-FGF, and forskolin. Cell differentiation into myocardial cells was monitored by RT-PCR, light microscopy, immunofluorescence, Western blot analysis, and contractile response to pharmacological treatments. The isolated olfactory bulb-derived fibroblast-like cells expressed CD29, CD44, CD90, CD105, CD166 but not CD34 and CD45, consistent with the characteristics of MSCs. Long cylindical cells that spontaneously contracted were only observed following 7 days of MSC co-culture with rat cardiomyocytes plus neuregulin-1, b-FGF and forskolin. RT-PCR and Western blot analysis indicated that the cylindrical cells expressed myocardial markers, such as Nkx2.5, GATA4, sarcomeric α-actinin, cardiac troponin I, cardiac myosin heavy chain, atrial natriuretic peptide and connexin 43. They also contained sarcomeres and gap junction and were sensitive to pharmacologic treatments (adrenal and cholinergic agonists and antagonists). These findings indicate that rat olfactory bulb derived fibroblast-like cells with MSC characteristics can differentiate into myocardial-like cells.

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Juin-Hong, Cherng, i 程君弘. "Grafting adult human olfactory stem cells as a therapeutic strategy to repair spinal cord injury". Thesis, 2005. http://ndltd.ncl.edu.tw/handle/20120196834479055187.

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碩士
國防醫學院
生物及解剖學研究所
93
Spinal cord injury is a major medical problem worldwide for scientists and clinicians. The failure of axons to regenerate in the adult central nervous system (CNS) has been attributed to a variety of factors including the glial scar, the presence of inhibitory factors and the lack of trophic factor support. Several strategies have been developed to rebuild the injured spinal cord in animals such as adding growth factors, providing bridges of peripheral nerves, olfactory ensheathing cells (OECs) or stem cells transplantation. Reviews these roles of transplantation, the recent discovery of OECs capable of generating central nervous system (CNS) tissues, coupled with success in neurotransplantation strategies, has renewed hope that repair and recovery from CNS trauma is possible. Based on results from several studies using OECs to promote CNS repair, our laboratory tried to recruit the human olfactory stem cells cultured from the human nasal polyp tissue, a common surgical specimen of patient’s nasal polyp in ear-nose-throat department. Several specific markers such as low affinity nerve growth factor receptor, p75NTR; oligodendrocyte marker 4, O4, schwann cell intermediate filament, S100-β, glial fibrillary aidic protein, GFAP were used to characterization after in vitro induced. Then, the human olfactory stem cells were transplanted into the spinal cord of the adult rats with complete spinal cord transection. The locomotor’s function of grafted animals were assessed by BBB score and already recovery to weight supporting; and the axonal regeneration were evaluated found by retrograde neuroanatornical tract tracer-Horseradish Peroxidase (HRP). Immunohistochemistry results prove the human olfactory stem cell survival and the new myelin formation after transplanted eight weeks at the beginning, and we believed the cells directly or indirectly promote the repair of injury. To our knowledge, we reprot for this frontier field that the improvement of hindlimb function after human olfactory stem cells transplantation in adult rats T8 transection injury. This work opens new avenue for the treatment of spinal cord injury with olfactory stem cells in human.

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Carter, Lindsay A. "Olfactory epithelial horizonal basal cells : an assessment of stem cell candidacy and behavioural regulation in vivo and in vitro". Thesis, 2002. http://hdl.handle.net/2429/12405.

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In the olfactory epithelium (OE), new olfactory receptor neurons (ORNS) are continually generated throughout mammalian adulthood. Given this substantial neuronal turnover, a stem cell is proposed to reside within the basal compartment of the OE, which generates ORNs on demand when stimulated by changes in its microenvironment. Although previous studies have identified possible candidates for the olfactory stem cell, its exact identity is as yet unknown. We hypothesize that a population o f horizontal basal cells (HBCs), situated upon the basement membrane of the OE, contains stem cells that contribute to olfactory neurogenesis. A major impediment to the study of these cells is the lack of reliable cell surface molecular markers to distinguish them from other OE cell types. By screening a panel of selected clusters of differentiation (CD) antigens, we have identified three new cell surface markers for the HBC population, namely intercellular adhesion molecule -1 (ICAM-1), β₁ integrin and β₄ integrin. Using these markers to characterize the HBC layer following bulbectomy-induced ORN loss, we have provided evidence of stem cell traits in vivo, including proliferative quiescence relative to OE progenitors, response to lesion, and possible molecular heterogeneity within the HBC compartment. In addition, these studies indicate changes in the populational and subcellular distribution of HBC markers upon loss of ORNs, suggesting a role for these adhesion receptors in the regulation of HBC function in addition to highlighting possible molecular similarities to stem cells of other self-renewing tissues. We have developed a method to select for HBCs in vitro using magnetic activated cell sorting (MACS) and by exploiting their expression of ICAM-1. Using in vitro colony-forming analyses, we obtained evidence that the ICAM-1+ population is enriched for progenitor activity. Further, the efficiency of colony formation can be modulated in vitro by growth factors and adhesive substrates. Lastly, immunohistochemical analysis demonstrated that globose basal cell (GBC) progenitors, ORNs and olfactory ensheathing glia (OEGs) are generated by the ICAM-1+ fraction in clonal culture. Based on these results, we conclude that ICAM-1+ HBCs contribute to the progenitor cell compartment, possibly as stem cells, during olfactory neurogenesis and that the function of these cells may be modulated via adhesion and growth factor signaling by components resident within their in vivo microenvironment.

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Alvites, Rui Damazio. "Combined use of Olfactory Mucosa Mesenchymal Stem Cells and Biomaterials in Regenerative Therapies after Peripheral Nerve Injury". Doctoral thesis, 2021. https://hdl.handle.net/10216/134928.

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Alvites, Rui Damazio. "Combined use of Olfactory Mucosa Mesenchymal Stem Cells and Biomaterials in Regenerative Therapies after Peripheral Nerve Injury". Tese, 2021. https://hdl.handle.net/10216/134928.

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Li, Ming-Yang, i 李明洋. "YAP Mediates TRIP6-Promoted Neural Stem Cell Maintenance in the Postnatal Mammalian Subventricular Zone-Olfactory Pathway and Its Applications". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/sgy63g.

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博士
國立臺灣師範大學
生命科學系
107
Postnatal neurogenesis in the dentate gyrus and subventricular zone (SVZ)-olfactory bulb pathway in mammals is regulated by extrinsic and intrinsic factors. Since endogenous neural stem cells (NSCs) in the adult brain have potential to treat neurodegenerative disorders, studying mechanisms regulating postnatal NSCs may provide clinical applications. However, the role of TRIP6, YAP and ginkgolide B in postnatal NSCs remain unclear. TRIP6 belongs to zyxin family of LIM proteins, which have been shown to interact with various proteins to regulate cell proliferation, survival and migration. We find that TRIP6 is expressed by adult NSCs in the SVZ but not migrating neuroblasts. TRIP6 is necessary and sufficient for self-renewal and proliferation of adult NSCs, but inhibits their differentiation. We also find that TRIP6 activates the Notch signaling, a pathway required for NSC self-renewal. Previous studies show that the Hippo pathway regulates cell proliferation and organ size through inhibiting YAP. We find that TRIP6 inhibits the Hippo pathway and activates YAP through PP1A. TRIP6 promotes NSC maintenance and proliferation and inhibits neuronal differentiation through YAP. During differentiation of NSCs, we also find that ginkgolide B promotes neurogenesis through the Wnt pathway. These findings show that YAP acts downstream of TRIP6 to promote adult NSC maintenance, whereas ginkgolide B promotes neurogenesis in the postnatal NSCs.

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Bouab, Meriem. "L’effet du vieillissement sur les cellules souches neurales adultes". Thèse, 2010. http://hdl.handle.net/1866/4222.

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La neurogenèse persiste à l’âge adulte dans deux régions du système nerveux central (SNC) des mammifères : la zone sous-ventriculaire (SVZ) du cerveau antérieur et la zone sous-granulaire (SGZ) de l’hippocampe. Cette neurogenèse est possible grâce à la capacité de prolifération des cellules souches présentes dans les niches de la SVZ et la SGZ, mais en vieillissant, le cerveau subit une diminution dramatique du nombre de cellules souches neurales adultes (CSNa), une diminution de la prolifération cellulaire et une altération des niches de neurogenèse. Cependant, une importante question reste sans réponse : comment la perte tardive des CSNa est temporellement reliée aux changements de l’activité de prolifération et de la structure de la principale niche de neurogenèse (la SVZ)? Afin d’avoir un aperçu sur les événements initiaux, nous avons examiné les changements des CSNa et de leur niche dans la SVZ entre le jeune âge et l’âge moyen. La niche de la SVZ des souris d’âge moyen (12 mois) subit une réduction de l’expression des marqueurs de plusieurs sous-populations de précurseurs neuraux en comparaison avec les souris jeunes adultes (2 mois). Anatomiquement, cela est associé avec des anomalies cytologiques, incluant une atrophie générale de la SVZ, une perte de la couche de cellules sousépendymaires par endroit et l’accumulation de gouttelettes lipidiques de grande taille dans l’épendyme. Fonctionnellement, ces changements sont corrélés avec une diminution de l’activité de la SVZ et une réduction du nombre de nouveaux neurones arrivant aux bulbes olfactifs. Pour déterminer si les CSNa de la SVZ ont subi des changements visibles, nous avons évalué les paramètres clés des CSNa in vivo et in vitro. La culture cellulaire montre qu’un nombre équivalent de CSNa ayant la capacité de former des neurosphères peut être isolé du cerveau du jeune adulte et d’âge moyen. Cependant, à l’âge moyen, les précurseurs neuraux semblent moins sensibles aux facteurs de croissance durant leur différenciation in vitro. Les CSNa donnent des signes de latence in vivo puisque leur capacité d’incorporation et de rétention du BrdU diminue. Ensemble, ces données démontrent que, tôt dans le processus du vieillissement, les CSNa et leur niche dans la SVZ subissent des changements significatifs, et suggèrent que la perte de CSNa liée au vieillissement est secondaire à ces événements.
Neurogenesis persists throughout the adulthood in two regions of the mammalian central nervous system (SNC): the sub-ventricular zone (SVZ) of the forebrain and the sub-granular zone (SGZ) of the hippocampus. Neurogenesis is possible due to the proliferation capacity of stem cells present within both the SVZ and SGZ niches, but with aging, the forebrain undergoes a drastic reduction in its number of adult neural stem cells (aNSCs), a decrease of cell proliferation and an alteration of the neurogenic niches. However, a key unresolved question remains: how the onset of aNSC loss is temporally related to changes of proliferating activity and to structural alterations within the principal stem cell niche (the SVZ)? To gain insights into the initial events leading to aging-associated aNSC loss, we investigated the changes occurring to aNSCs and the SVZ niche between young adulthood and middle-age. The SVZ niche of middle-aged mice (12-months-old) was found to display reduced expression of markers for multiple neural precursor sub-populations when compared to young adult mice (2-months-old). Anatomically, this was associated with significant cytological aberrations, including an overall atrophy of the SVZ, loss of sub-ependymal cells, and accumulation of large lipid droplets within the ependyma. Functionally, these changes correlated with diminished SVZ activity and reduced number of newly born neurons reaching the principal target tissue: the olfactory bulbs. To determine whether changes were evident at the level of the SVZ stem cells, we evaluated key in vitro and in vivo parameters of aNSCs. Tissue culture experiments showed that equal numbers of neurosphere-forming aNSCs could be isolated from young adult and middle-aged forebrains. However, at middle-age, neural precursors seemed to be less sensitive to growth factors during their in vitro differentiation and displayed signs of increased quiescence in vivo. Collectively, these findings demonstrate that, with early aging, aNCS and their SVZ niche go through significant changes, and suggest that aging-associated aNSC loss is secondary to these events.

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