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1.
Jt Comm J Qual Patient Saf ; 50(1): 75-82, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38061944

RESUMEN

Performance improvement methodologies do not currently include any structures that encourage analysis of how bias, inequity, or social determinants of health (SDOH) contribute to outcomes. The Montefiore Center for Performance Improvement developed a novel quality improvement (QI) toolkit that ingrains issues of diversity, equity, and inclusion (DEI) and SDOH into the Institute for Healthcare Improvement's tools. The toolkit prompts QI teams to evaluate DEI and SDOH at each step of the journey, including an updated charter and stratified baseline tool, a new fishbone diagram for the discovery phase with a tail to include DEI and SDOH, and additions in the Study and Act sessions of the Plan-Do-Study-Act worksheet to address these issues. After development and dissemination of this toolkit, the authors conducted a pre-post analysis of projects conducted by QI fellows in their institution. Prior to introducing the new toolkit, 22.9% of projects from 2016 to 2021 incorporated DEI/SDOH into any stage of the QI process. After implementing the amended tools, this increased to 88.9% in the 2022 fellowship. These results show that this simple approach can hardwire consideration of DEI and SDOH into improvement projects.


Asunto(s)
Mejoramiento de la Calidad , Determinantes Sociales de la Salud , Humanos , Encuestas y Cuestionarios
2.
Biomedicines ; 11(2)2023 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-36831063

RESUMEN

Diffuse midline glioma (DMG) is an aggressive brain tumour with high mortality and limited clinical therapeutic options. Although in vitro research has shown the effectiveness of medication, successful translation to the clinic remains elusive. A literature search highlighted the high variability and lack of standardisation in protocols applied for establishing the commonly used HSJD-DIPG-007 patient-derived xenograft (PDX) model, based on animal host, injection location, number of cells inoculated, volume, and suspension matrices. This study evaluated the HSJD-DIPG-007 PDX model with respect to its ability to mimic human disease progression for therapeutic testing in vivo. The mice received intracranial injections of HSJD-DIPG-007 cells suspended in either PBS or Matrigel. Survival, tumour growth, and metastases were assessed to evaluate differences in the suspension matrix used. After cell implantation, no severe side effects were observed. Additionally, no differences were detected in terms of survival or tumour growth between the two suspension groups. We observed delayed metastases in the Matrigel group, with a significant difference compared to mice with PBS-suspended cells. In conclusion, using Matrigel as a suspension matrix is a reliable method for establishing a DMG PDX mouse model, with delayed metastases formation and is a step forward to obtaining a standardised in vivo PDX model.

3.
Br J Cancer ; 127(7): 1193-1200, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35715639

RESUMEN

High-grade gliomas, in particularly diffuse midline glioma, H3K27-altered in children and glioblastoma in adults, are the most lethal brain tumour with a dismal prognosis. Developments in modern medicine are constantly being applied in the search for a cure, although finding the right strategy remains elusive. Circumventing the blood-brain barrier is one of the biggest challenges when it comes to treating brain tumours. The cat and mouse game of finding the Trojan horse to traverse this barrier and deliver therapeutics to the brain has been a long and hard-fought struggle. Research is ongoing to find new and feasible ways to reach specific targets in the brain, with a special focus on inoperable or recurring brain tumours. Many options and combinations of options have been tested to date and continue to be so in the search to find the most effective and least toxic treatment paradigm. Although improvements are often small and slow, some of these strategies have already shown promise, shining a light of hope that finding the cure is feasible. In this review, we discuss recent findings that elucidate promising but atypical strategies for targeting gliomas and the implications that this work has on developing new treatment regimens.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Glioma , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Glioblastoma/tratamiento farmacológico , Glioma/tratamiento farmacológico , Glioma/patología , Humanos , Recurrencia Local de Neoplasia , Pronóstico
4.
Nanomedicine (Lond) ; 13(16): 1999-2013, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-30204064

RESUMEN

AIM: Anticancer drug-loaded hydrogels are a promising strategy for the local treatment of incurable brain tumors such as glioblastoma (GBM). Recently, we demonstrated the efficacy of lauroyl-gemcitabine lipid nanocapsule hydrogel (GemC12-LNC) in a U-87 MG xenograft orthotopic mouse model. In this study, we developed a reliable and reproducible surgical procedure to resect orthotopic GBM tumors in rats. GemC12-LNC hydrogel integrity was tested after brain administration in rats and its anti-tumor efficacy was tested on a 9L syngeneic orthotopic model. RESULTS: We demonstrated that LNC integrity is maintained at least for one week after local administration of GemC12-LNC. GemC12-LNC was able to delay the formation of recurrences in 9L tumor-bearing resected rats, demonstrating the efficacy of this nanomedicine hydrogel in this preclinical model. CONCLUSION: Our results confirm that GemC12-LNC, a hydrogel uniquely formed by a nanocarrier and a cytotoxic drug, could be a promising and safe delivery tool for the local treatment of operable GBM tumors.


Asunto(s)
Neoplasias Encefálicas/tratamiento farmacológico , Desoxicitidina/análogos & derivados , Glioblastoma/tratamiento farmacológico , Hidrogeles/química , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Desoxicitidina/administración & dosificación , Desoxicitidina/química , Desoxicitidina/uso terapéutico , Femenino , Imagen por Resonancia Magnética , Nanomedicina/métodos , Ratas , Ratas Sprague-Dawley , Gemcitabina
5.
Int J Nanomedicine ; 13: 4509-4521, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30127603

RESUMEN

INTRODUCTION: Glioblastoma (GBM) therapy is highly challenging, as the tumors are very aggressive due to infiltration into the surrounding normal brain tissue. Even a combination of the available therapeutic regimens may not debulk the tumor completely. GBM tumors are also known for recurrence, resulting in survival rates averaging <18 months. In addition, systemic chemotherapy for GBM has been challenged for its minimal desired therapeutic effects and unwanted side effects. PURPOSE: We hypothesized that paclitaxel (PTX) and superparamagnetic iron oxide (SPIO)-loaded PEGylated poly(lactic-co-glycolic acid) (PLGA)-based nanoparticles (NPs; PTX/SPIO-NPs) can serve as an effective nanocarrier system for magnetic targeting purposes, and we aimed to demonstrate the therapeutic efficacy of this system in an orthotopic murine GBM model. MATERIALS AND METHODS: PTX/SPIO-NPs were prepared by emulsion-diffusion-evaporation method and characterized for physicochemical properties. In vitro cellular uptake of PTX/SPIO-NPs was evaluated by fluorescence microscopy and Prussian blue staining. Orthotopic U87MG tumor model was used to evaluate blood-brain barrier disruption using T1 contrast agent, ex vivo biodistribution, in vivo toxicity and in vivo antitumor efficacy of PTX/SPIO-NPs. RESULTS: PTX/SPIO-NPs were in the size of 250 nm with negative zeta potential. Qualitative cellular uptake studies showed that the internalization of NPs was concentration dependent. Through magnetic resonance imaging, we observed that the blood-brain barrier was disrupted in the GBM area. An ex vivo biodistribution study showed enhanced accumulation of NPs in the brain of GBM-bearing mice with magnetic targeting. Short-term in vivo safety evaluation showed that the NPs did not induce any systemic toxicity compared with Taxol® (PTX). When tested for in vivo efficacy, the magnetic targeting treatment significantly prolonged the median survival time compared with the passive targeting and control treatments. CONCLUSION: Overall, PTX/SPIO-NPs with magnetic targeting could be considered as an effective anticancer targeting strategy for GBM chemotherapy.


Asunto(s)
Glioblastoma/tratamiento farmacológico , Ácido Láctico/química , Magnetismo , Nanopartículas/química , Paclitaxel/uso terapéutico , Ácido Poliglicólico/química , Animales , Barrera Hematoencefálica/efectos de los fármacos , Barrera Hematoencefálica/patología , Línea Celular Tumoral , Endocitosis/efectos de los fármacos , Femenino , Glioblastoma/patología , Humanos , Ratones Desnudos , Paclitaxel/farmacología , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Análisis de Supervivencia , Distribución Tisular/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
6.
Int J Pharm ; 548(1): 522-529, 2018 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-30017818

RESUMEN

Glioblastoma multiforme (GBM) is the most common primary malignant brain tumor. Despite available therapeutic options, the prognosis for patients with GBM remains very poor. We hypothesized that the intra-operative injection of a photopolymerizable hydrogel into the tumor resection cavity could sustain the release of the anti-cancer drug paclitaxel (PTX) encapsulated in poly (lactic-co-glycolic acid) (PLGA) nanoparticles and prevent GBM recurrence. The tumor was resected 13 days after implantation and a pre-gel solution composed of polyethylene glycol dimethacrylate (PEG-DMA) polymer, a photoinitiator and PTX-loaded PLGA nanoparticles (PTX PLGA-NPs) was injected into the tumor resection cavity. A solid gel filling the whole cavity was formed immediately by photopolymerization using a 400 nm light. PTX in vitro release study showed a burst release (11%) in the first 8 h and a sustained release of 29% over a week. In vitro, U87 MG cells were sensitive to PTX PLGA-NPs with IC50 level of approximately 0.010 µg/mL. The hydrogel was well-tolerated when implanted in the brain of healthy mice for 2 and 4 months. Administration of PTX PLGA-NPs-loaded hydrogel into the resection cavity of GBM orthotopic model lead to more than 50% long-term survival mice (150 days) compared to the control groups (mean survival time 52 days). This significant delay of recurrence is very promising for the post-resection treatment of GBM.


Asunto(s)
Antineoplásicos Fitogénicos/administración & dosificación , Neoplasias Encefálicas/tratamiento farmacológico , Glioblastoma/tratamiento farmacológico , Hidrogeles/administración & dosificación , Nanopartículas/administración & dosificación , Paclitaxel/administración & dosificación , Animales , Antineoplásicos Fitogénicos/química , Apoptosis/efectos de los fármacos , Neoplasias Encefálicas/cirugía , Línea Celular Tumoral , Preparaciones de Acción Retardada/administración & dosificación , Preparaciones de Acción Retardada/química , Liberación de Fármacos , Femenino , Glioblastoma/cirugía , Humanos , Hidrogeles/química , Periodo Intraoperatorio , Ácido Láctico/administración & dosificación , Ácido Láctico/química , Metacrilatos/administración & dosificación , Metacrilatos/química , Ratones , Nanopartículas/química , Paclitaxel/química , Polietilenglicoles/administración & dosificación , Polietilenglicoles/química , Ácido Poliglicólico/administración & dosificación , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico
7.
Cell Mol Life Sci ; 75(15): 2857, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29569030

RESUMEN

In the original publication, sixth author's surname was incorrectly published as "Llyod" instead of "Lloyd". The correct name should read as "Amy Lloyd".

8.
Cell Mol Life Sci ; 75(15): 2843-2856, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29417177

RESUMEN

Secondary damage following spinal cord injury leads to non-reversible lesions and hampering of the reparative process. The local production of pro-inflammatory cytokines such as TNF-α can exacerbate these events. Oligodendrocyte death also occurs, followed by progressive demyelination leading to significant tissue degeneration. Dental stem cells from human apical papilla (SCAP) can be easily obtained at the removal of an adult immature tooth. This offers a minimally invasive approach to re-use this tissue as a source of stem cells, as compared to biopsying neural tissue from a patient with a spinal cord injury. We assessed the potential of SCAP to exert neuroprotective effects by investigating two possible modes of action: modulation of neuro-inflammation and oligodendrocyte progenitor cell (OPC) differentiation. SCAP were co-cultured with LPS-activated microglia, LPS-activated rat spinal cord organotypic sections (SCOS), and LPS-activated co-cultures of SCOS and spinal cord adult OPC. We showed for the first time that SCAP can induce a reduction of TNF-α expression and secretion in inflamed spinal cord tissues and can stimulate OPC differentiation via activin-A secretion. This work underlines the potential therapeutic benefits of SCAP for spinal cord injury repair.


Asunto(s)
Activinas/metabolismo , Diferenciación Celular/fisiología , Papila Dental/metabolismo , Inflamación/prevención & control , Células Precursoras de Oligodendrocitos/metabolismo , Células Madre/metabolismo , Adulto , Animales , Línea Celular , Enfermedades Desmielinizantes/metabolismo , Enfermedades Desmielinizantes/prevención & control , Papila Dental/citología , Humanos , Inflamación/metabolismo , Ratones , Neuronas/metabolismo , Oligodendroglía/metabolismo , Ratas , Ratas Wistar , Médula Espinal/metabolismo , Traumatismos de la Médula Espinal/metabolismo , Traumatismos de la Médula Espinal/terapia , Células Madre/citología , Factor de Necrosis Tumoral alfa/metabolismo
9.
J Neurosci Methods ; 284: 96-102, 2017 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-28472680

RESUMEN

In vitro and in vivo models of experimental glioma are useful tools to gain a better understanding of glioblastoma (GBM) and to investigate novel treatment strategies. However, the majority of preclinical models focus on treating solid intracranial tumours, despite surgical resection being the mainstay in the standard care of patients with GBM today. The lack of resection and recurrence models therefore has undermined efforts in finding a treatment for this disease. Here we present a novel orthotopic tumour resection and recurrence model that has potential for the investigation of local delivery strategies in the treatment of GBM. The model presented is simple to achieve through the use of a biopsy punch, is reproducible, does not require specific or expensive equipment, and results in a resection cavity suitable for local drug delivery systems, such as the implantation or injection of hydrogels. We show that tumour resection is well tolerated, does not induce deleterious neurological deficits, and significantly prolongs survival of mice bearing U-87 MG GBM tumours. In addition, the resulting cavity could accommodate adequate amounts of hydrogels for local delivery of chemotherapeutic agents to eliminate residual tumour cells that can induce tumour recurrence.


Asunto(s)
Neoplasias Encefálicas/patología , Neoplasias Encefálicas/cirugía , Modelos Animales de Enfermedad , Glioblastoma/patología , Glioblastoma/cirugía , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/cirugía , Animales , Línea Celular Tumoral , Femenino , Humanos , Ratones , Ratones Desnudos
10.
Stem Cell Rev Rep ; 13(4): 499-512, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28509260

RESUMEN

Oligodendrocyte progenitor cells (OPCs) play a pivotal role in both health and disease within the central nervous system, with oligodendrocytes, arising from resident OPCs, being the main myelinating cell type. Disruption in OPC numbers can lead to various deleterious health defects. Numerous studies have described techniques for isolating OPCs to obtain a better understanding of this cell type and to open doors for potential treatments of injury and disease. However, the techniques used in the majority of these studies involve several steps and are time consuming, with current culture protocols using serum and embryonic or postnatal cortical tissue as a source of isolation. We present a primary culture method for the direct isolation of functional adult rat OPCs, identified by neuron-glial antigen 2 (NG2) and platelet derived growth factor receptor alpha (PDGFrα) expression, which can be obtained from the adult spinal cord. Our method uses a simple serum-free cocktail of 3 growth factors - FGF2, PDGFAA, and IGF-I, to expand adult rat OPCs in vitro to 96% purity. Cultured cells can be expanded for at least 10 passages with very little manipulation and without losing their phenotypic progenitor cell properties, as shown by immunocytochemistry and RT-PCR. Cultured adult rat OPCs also maintain their ability to differentiate into GalC positive cells when incubated with factors known to stimulate their differentiation. This new isolation method provides a new source of easily accessible adult stem cells and a powerful tool for their expansion in vitro for studies aimed at central nervous system repair.


Asunto(s)
Células Madre Adultas/metabolismo , Separación Celular , Oligodendroglía/metabolismo , Médula Espinal/metabolismo , Células Madre Adultas/citología , Animales , Antígenos/metabolismo , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Oligodendroglía/citología , Factor de Crecimiento Derivado de Plaquetas/metabolismo , Proteoglicanos/metabolismo , Ratas , Ratas Sprague-Dawley , Médula Espinal/citología
11.
Cell Mol Life Sci ; 74(13): 2451-2466, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28210785

RESUMEN

Although brain tumours have been documented and recorded since the nineteenth century, 2016 marked 90 years since Percival Bailey and Harvey Cushing coined the term "glioblastoma multiforme". Since that time, although extensive developments in diagnosis and treatment have been made, relatively little improvement on prognosis has been achieved. The resilience of GBM thus makes treating this tumour one of the biggest challenges currently faced by neuro-oncology. Aggressive and robust development, coupled with difficulties of complete resection, drug delivery and therapeutic resistance to treatment are some of the main issues that this nemesis presents today. Current treatments are far from satisfactory with poor prognosis, and focus on palliative management rather than curative intervention. However, therapeutic research leading to developments in novel treatment stratagems show promise in combating this disease. Here we present a review on GBM, looking at the history and advances which have shaped neurosurgery over the last century that cumulate to the present day management of GBM, while also exploring future perspectives in treatment options that could lead to new treatments on the road to a cure.


Asunto(s)
Neoplasias Encefálicas/terapia , Glioblastoma/terapia , Animales , Neoplasias Encefálicas/patología , Ensayos Clínicos como Asunto , Resistencia a Antineoplásicos , Glioblastoma/patología , Humanos , Células Madre Neoplásicas/patología
12.
Int J Pharm ; 499(1-2): 81-89, 2016 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-26721725

RESUMEN

Drug access to the CNS is hindered by the presence of the blood-brain barrier (BBB), and the intranasal route has risen as a non-invasive route to transport drugs directly from nose-to-brain avoiding the BBB. In addition, nanoparticles (NPs) have been described as efficient shuttles for direct nose-to-brain delivery of drugs. Nevertheless, there are few studies describing NP nose-to-brain transport. Thus, the aim of this work was (i) to develop, characterize and validate in vitro olfactory cell monolayers and (ii) to study the transport of polymeric- and lipid-based NPs across these monolayers in order to estimate NP access into the brain using cell penetrating peptide (CPPs) moieties: Tat and Penetratin (Pen). All tested poly(d,l-lactide-co-glycolide) (PLGA) and nanostructured lipid carrier (NLC) formulations were stable in transport buffer and biocompatible with the olfactory mucosa cells. Nevertheless, 0.7% of PLGA NPs was able to cross the olfactory cell monolayers, whereas 8% and 22% of NLC and chitosan-coated NLC (CS-NLC) were transported across them, respectively. Moreover, the incorporation of CPPs to NLC surface significantly increased their transport, reaching 46% of transported NPs. We conclude that CPP-CS-NLC represent a promising brain shuttle via nose-to-brain for drug delivery.


Asunto(s)
Barrera Hematoencefálica/metabolismo , Sistemas de Liberación de Medicamentos , Nanopartículas , Mucosa Olfatoria/metabolismo , Administración Intranasal , Animales , Transporte Biológico , Encéfalo/metabolismo , Péptidos de Penetración Celular/química , Química Farmacéutica/métodos , Quitosano/química , Femenino , Ácido Láctico/química , Lípidos/química , Mucosa Nasal/metabolismo , Mucosa Olfatoria/citología , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Polímeros/química , Ratas , Ratas Wistar
13.
Cell Mol Life Sci ; 73(7): 1413-37, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26768693

RESUMEN

Dental stem cells are an emerging star on a stage that is already quite populated. Recently, there has been a lot of hype concerning these cells in dental therapies, especially in regenerative endodontics. It is fitting that most research is concentrated on dental regeneration, although other uses for these cells need to be explored in more detail. Being a true mesenchymal stem cell, their capacities could also prove beneficial in areas outside their natural environment. One such field is the central nervous system, and in particular, repairing the injured spinal cord. One of the most formidable challenges in regenerative medicine is to restore function to the injured spinal cord, and as yet, a cure for paralysis remains to be discovered. A variety of approaches have already been tested, with graft-based strategies utilising cells harbouring appropriate properties for neural regeneration showing encouraging results. Here we present a review focusing on properties of dental stem cells that endorse their use in regenerative medicine, with particular emphasis on repairing the damaged spinal cord.


Asunto(s)
Pulpa Dental/citología , Traumatismos de la Médula Espinal/terapia , Trasplante de Células Madre , Animales , Humanos , Factores de Crecimiento Nervioso/metabolismo , Receptores de Factor de Crecimiento Nervioso/metabolismo , Medicina Regenerativa , Células Madre/citología
14.
Biol Aujourdhui ; 208(1): 69-75, 2014.
Artículo en Francés | MEDLINE | ID: mdl-24948020

RESUMEN

In 2014, a phase II randomised, double blind clinical trial assessing the efficacy of cholecalciferol (vitamin D3) in patients with a cervical trauma will be set up. This trial stems from previous studies showing that vitamin D supplementation improves functional recovery in rat models of peripheral or central nerve injury. In a first series of experiments, we used a rat model of peripheral nerve trauma to demonstrate the therapeutic efficiency of vitamin D. We first demonstrated that ergocalciferol (vitamin D2) increases the number and the diameter of newly formed axons and improves the response of metabosensitive fibers from tibialis muscle, in a model of transected peroneal nerve. Then, we compared vitamin D2 and vitamin D3 and observed that the latter is more efficient. At the dose of 500 IU/kg/day, vitamin D3 induces a dramatic functional recovery. We also demonstrated that vitamin D3 increases the number of preserved or newly formed axons in the proximal end, the mean axon diameter in the distal end, neurite myelination in both the distal and proximal ends as well as the expression of genes involved in axogenesis and myelination. In parallel, we assessed the therapeutic role of vitamin D on the central nervous system. In a first study, using a rat model of spinal cord compression at the T10 thoracic level, we delivered vitamin D3 (cholecalciferol) orally at the dose of 50 IU/kg/day or 200 IU/kg/day. When compared to control animals, vitamin D-treated rats displayed, three months after injury, a significant improvement of ventilatory frequency and a reduction of H reflex indicating functional improvements at three months post-injury. In a second study, we used a rat model of cervical hemisection (C2) with a higher dose of oral vitamin D3 (500 IU/kg/day) delivered weekly, during 12 weeks. We observed an improved locomotor recovery, a reduced spasticity and a significantly higher rate of axons crossing the lesion site in treated animals. However, it must be pointed out that the functional improvement is reduced when vitamin D is provided one week after the trauma.


Asunto(s)
Traumatismos de la Médula Espinal/tratamiento farmacológico , Vitamina D/uso terapéutico , Animales , Axones/efectos de los fármacos , Axotomía , Vértebras Cervicales , Colecalciferol/administración & dosificación , Colecalciferol/uso terapéutico , Enfermedades Desmielinizantes/tratamiento farmacológico , Evaluación Preclínica de Medicamentos , Ergocalciferoles/administración & dosificación , Ergocalciferoles/uso terapéutico , Regulación de la Expresión Génica , Humanos , Músculo Esquelético/inervación , Fibras Nerviosas Mielínicas/efectos de los fármacos , Regeneración Nerviosa/efectos de los fármacos , Fármacos Neuroprotectores/administración & dosificación , Fármacos Neuroprotectores/uso terapéutico , Nervio Peroneo/lesiones , Ratas , Vitamina D/administración & dosificación , Vitamina D/fisiología
15.
PLoS One ; 8(8): e71334, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23967194

RESUMEN

The discovery of stem cells in the adult human brain has revealed new possible scenarios for treatment of the sick or injured brain. Both clinical use of and preclinical research on human adult neural stem cells have, however, been seriously hampered by the fact that it has been impossible to passage these cells more than a very few times and with little expansion of cell numbers. Having explored a number of alternative culturing conditions we here present an efficient method for the establishment and propagation of human brain stem cells from whatever brain tissue samples we have tried. We describe virtually unlimited expansion of an authentic stem cell phenotype. Pluripotency proteins Sox2 and Oct4 are expressed without artificial induction. For the first time multipotency of adult human brain-derived stem cells is demonstrated beyond tissue boundaries. We characterize these cells in detail in vitro including microarray and proteomic approaches. Whilst clarification of these cells' behavior is ongoing, results so far portend well for the future repair of tissues by transplantation of an adult patient's own-derived stem cells.


Asunto(s)
Encéfalo/citología , Técnicas de Cultivo de Célula/métodos , Células Madre Multipotentes/citología , Adulto , Biomarcadores/metabolismo , Diferenciación Celular , Células Clonales/citología , Neuronas Dopaminérgicas/citología , Regulación de la Expresión Génica , Humanos , Cariotipificación , Persona de Mediana Edad , Células Madre Multipotentes/metabolismo , Fenotipo , Proteómica , Coloración y Etiquetado
16.
Glia ; 59(5): 750-70, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21360755

RESUMEN

Olfactory ensheathing cells (OECs) are unique glia found only in the olfactory system. They retain exceptional plasticity and support olfactory neurogenesis and retargeting across the PNS:CNS boundary in the olfactory system. OECs have been shown to improve functional outcome when transplanted into rodents with spinal cord injury. The growth-promoting properties of implanted OECs encompass their ability to migrate through the scar tissue and render it more permissive for axonal outgrowth, but the underlying molecular mechanisms remain poorly understood. OECs appear to regulate molecules of the extracellular matrix (ECM) that inhibit axonal growth. Among the proteins that have the potential to promote cell migration, axonal regeneration and remodeling of the ECM are matrix metalloproteinases (MMPs), a family of endopeptidases that cleave matrix, soluble, and membrane-bound proteins and that are regulated by their endogenous inhibitors, the tissue inhibitors of MMPs (TIMPs). Little is known about MMP/TIMP trafficking, secretion, and role in OECs. Using a combination of cell biology, biochemistry, pharmacology, and imaging techniques, we show that MMP-2 and MMP-9 are expressed and proteolytically active in the olfactory epithelium and in particular in the OECs of the lamina propria. These proteinases and regulatory proteins such as MT1-MMP and TIMP-2 are expressed in cultured OECs. MMPs exhibit nuclear localization and vesicular trafficking and secretion, with distribution along microtubules and microfilaments and co-localization with the molecular motor protein kinesin. Finally, we show that MMPs are involved in migration of OECs in vitro on different ECM substrates.


Asunto(s)
Movimiento Celular/fisiología , Metaloproteinasa 2 de la Matriz/metabolismo , Neuroglía/metabolismo , Mucosa Olfatoria/metabolismo , Animales , Western Blotting , Células Cultivadas , Femenino , Técnica del Anticuerpo Fluorescente , Inmunohistoquímica , Metaloproteinasa 9 de la Matriz/metabolismo , Mucosa Olfatoria/citología , Transporte de Proteínas/fisiología , Ratas , Ratas Endogámicas Lew , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Inhibidor Tisular de Metaloproteinasa-2/metabolismo
17.
Auton Neurosci ; 154(1-2): 20-9, 2010 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-19896908

RESUMEN

Autonomic dysreflexia is a common complication in high spinal cord injury and can result in serious consequences and death. Here we have examined the effect of acute transplantation of olfactory ensheathing cells on cardiovascular functions in rats. After T4 transection, radio-telemetric recording in conscious animals was used to study blood pressure and heart rate at rest and during autonomic dysreflexia for up to 8 weeks post-injury. Olfactory ensheathing cells from syngeneic rats were transplanted at the injury site; control animals received culture medium only. At the study end point, we examined morphometric features of sympathetic preganglionic neurons above and below the injury. T4 transection resulted in a fall in resting mean arterial pressure and an increase in resting heart rate. Colorectal distension, used to trigger autonomic dysreflexia, caused episodic hypertension and bradycardia. Although the cell transplantation had no effect on resting cardiovascular parameters, it led to a significantly faster recovery from hypertension, with the recovery time shortened by approximately 25%. The transection resulted in an increase in soma size of sympathetic preganglionic neurons above and below the injury. OEC transplantation normalised this change below the injury and increased dendritic length of preganglionic neurons above the injury, compared to controls. It has been proposed that changes in sympathetic preganglionic neurons following spinal cord transection may be related to the development of autonomic dysreflexia. Our results suggest that olfactory ensheathing cells may alter the morphology of these neurons, and hence modify their activity in the neuronal networks responsible for the dysreflexic reaction.


Asunto(s)
Disreflexia Autónoma/etiología , Disreflexia Autónoma/cirugía , Neuroglía/fisiología , Bulbo Olfatorio/citología , Traumatismos de la Médula Espinal/complicaciones , Análisis de Varianza , Animales , Disreflexia Autónoma/patología , Fibras Autónomas Preganglionares/metabolismo , Fibras Autónomas Preganglionares/patología , Presión Sanguínea/fisiología , Recuento de Células/métodos , Supervivencia Celular/fisiología , Trasplante de Células/métodos , Modelos Animales de Enfermedad , Tracto Gastrointestinal/fisiopatología , Proteínas Fluorescentes Verdes/metabolismo , Frecuencia Cardíaca/fisiología , Masculino , NADPH Deshidrogenasa , Neuronas/metabolismo , Ratas , Ratas Wistar , Médula Espinal/metabolismo , Médula Espinal/patología , Sistema Nervioso Simpático/patología , Telemetría/métodos , Factores de Tiempo , Tubulina (Proteína)/metabolismo
18.
Stem Cells ; 26(8): 2183-92, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18535154

RESUMEN

Parkinson's disease is a complex disorder characterized by degeneration of dopaminergic neurons in the substantia nigra in the brain. Stem cell transplantation is aimed at replacing dopaminergic neurons because the most successful drug therapies affect these neurons and their synaptic targets. We show here that neural progenitors can be grown from the olfactory organ of humans, including those with Parkinson's disease. These neural progenitors proliferated and generated dopaminergic cells in vitro. They also generated dopaminergic cells when transplanted into the brain and reduced the behavioral asymmetry induced by ablation of the dopaminergic neurons in the rat model of Parkinson's disease. Our results indicate that Parkinson's patients could provide their own source of neuronal progenitors for cell transplantation therapies and for direct investigation of the biology and treatments of Parkinson's disease. Disclosure of potential conflicts of interest is found at the end of this article.


Asunto(s)
Dopamina/metabolismo , Mucosa Olfatoria/metabolismo , Enfermedad de Parkinson/metabolismo , Enfermedad de Parkinson/terapia , Trasplante de Células Madre/métodos , Animales , Biopsia , Encéfalo/metabolismo , Diferenciación Celular , Linaje de la Célula , Femenino , Humanos , Neuronas/metabolismo , Ratas , Ratas Sprague-Dawley , Trasplante Autólogo
19.
Dev Dyn ; 233(2): 496-515, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15782416

RESUMEN

Multipotent stem cells are thought to be responsible for the generation of new neurons in the adult brain. Neurogenesis also occurs in an accessible part of the nervous system, the olfactory mucosa. We show here that cells from human olfactory mucosa generate neurospheres that are multipotent in vitro and when transplanted into the chicken embryo. Cloned neurosphere cells show this multipotency. Multipotency was evident without prior culture in vitro: cells dissociated from adult rat olfactory mucosa generate leukocytes when transplanted into bone marrow-irradiated hosts, and cells dissociated from adult mouse olfactory epithelium generated numerous cell types when transplanted into the chicken embryo. It is unlikely that these results can be attributed to hematopoietic precursor contamination or cell fusion. These results demonstrate the existence of a multipotent stem-like cell in the olfactory mucosa useful for autologous transplantation therapies and for cellular studies of disease.


Asunto(s)
Envejecimiento/fisiología , Diferenciación Celular , Células Madre Multipotentes/citología , Mucosa Olfatoria/citología , Adulto , Factores de Edad , Anciano , Animales , Biopsia , Fusión Celular , Linaje de la Célula , Células Cultivadas , Embrión de Pollo , Células Epiteliales/citología , Femenino , Hematopoyesis , Humanos , Masculino , Ratones , Persona de Mediana Edad , Neuroglía/citología , Neuronas/citología , Ratas
20.
Glia ; 45(2): 111-23, 2004 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-14730705

RESUMEN

Several studies have demonstrated the potential of olfactory ensheathing cells for the repair of central and peripheral nerve injury. However, the majority of these studies have been performed with olfactory ensheathing cells derived from the olfactory bulbs, situated inside the skull. A more clinically relevant source of olfactory ensheathing cells is the olfactory mucosa, located in the nose. To be successful, an autologous transplant of nasal ensheathing glia would require a large number of purified cells. To address this issue, we have focused our research on three neurotrophic factors, namely nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and neurotrophin 3 (NT3). We show here that their respective receptors, TrkA, TrkB, TrkC, as well as p75(NTR) (the low affinity NGF receptor), are expressed in vitro by the nasal ensheathing cells; the three neurotrophins promote purification and proliferation of these glial cells, with an optimal concentration of 50 ng/ml; and human ensheathing cells can be easily biopsied and highly purified using a serum-free medium supplemented with NT3. This technique opens the door for clinical trials in which nasal ensheathing cells will be autotransplanted in humans suffering from nerve injury.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Neuroglía/efectos de los fármacos , Neurotrofina 3/farmacología , Mucosa Olfatoria/citología , Adulto , Anciano , Animales , Biopsia/métodos , Factor Neurotrófico Derivado del Encéfalo/farmacología , Factor Neurotrófico Derivado del Encéfalo/uso terapéutico , Separación Celular , Células Cultivadas , Medio de Cultivo Libre de Suero/farmacología , Femenino , Proteína Ácida Fibrilar de la Glía/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Factor de Crecimiento Nervioso/farmacología , Factor de Crecimiento Nervioso/uso terapéutico , Regeneración Nerviosa/fisiología , Neuroglía/citología , Neuroglía/trasplante , Neurotrofina 3/uso terapéutico , ARN Mensajero/efectos de los fármacos , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Receptor de Factor de Crecimiento Nervioso , Receptor trkA/efectos de los fármacos , Receptor trkA/genética , Receptor trkA/metabolismo , Receptor trkB/efectos de los fármacos , Receptor trkB/genética , Receptor trkB/metabolismo , Receptor trkC/efectos de los fármacos , Receptor trkC/genética , Receptor trkC/metabolismo , Receptores de Factor de Crecimiento Nervioso/efectos de los fármacos , Receptores de Factor de Crecimiento Nervioso/genética , Receptores de Factor de Crecimiento Nervioso/metabolismo , Proteínas S100/metabolismo , Trasplante Autólogo/métodos
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