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1.
Acta Neuropathol ; 148(1): 43, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39283487

RESUMEN

Amyotrophic Lateral Sclerosis (ALS) is a multisystemic neurodegenerative disorder, with accumulating evidence indicating metabolic disruptions in the skeletal muscle preceding disease symptoms, rather than them manifesting as a secondary consequence of motor neuron (MN) degeneration. Hence, energy homeostasis is deeply implicated in the complex physiopathology of ALS and skeletal muscle has emerged as a key therapeutic target. Here, we describe intrinsic abnormalities in ALS skeletal muscle, both in patient-derived muscle cells and in muscle cell lines with genetic knockdown of genes related to familial ALS, such as TARDBP (TDP-43) and FUS. We found a functional impairment of myogenesis that parallels defects of glucose oxidation in ALS muscle cells. We identified FOXO1 transcription factor as a key mediator of these metabolic and functional features in ALS muscle, via gene expression profiling and biochemical surveys in TDP-43 and FUS-silenced muscle progenitors. Strikingly, inhibition of FOXO1 mitigated the impaired myogenesis in both the genetically modified and the primary ALS myoblasts. In addition, specific in vivo conditional knockdown of TDP-43 or FUS orthologs (TBPH or caz) in Drosophila muscle precursor cells resulted in decreased innervation and profound dysfunction of motor nerve terminals and neuromuscular synapses, accompanied by motor abnormalities and reduced lifespan. Remarkably, these phenotypes were partially corrected by foxo inhibition, bolstering the potential pharmacological management of muscle intrinsic abnormalities associated with ALS. The findings demonstrate an intrinsic muscle dysfunction in ALS, which can be modulated by targeting FOXO factors, paving the way for novel therapeutic approaches that focus on the skeletal muscle as complementary target tissue.


Asunto(s)
Esclerosis Amiotrófica Lateral , Proteína Forkhead Box O1 , Músculo Esquelético , Esclerosis Amiotrófica Lateral/metabolismo , Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/patología , Humanos , Animales , Músculo Esquelético/metabolismo , Músculo Esquelético/patología , Proteína Forkhead Box O1/metabolismo , Proteína Forkhead Box O1/genética , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Masculino , Proteína FUS de Unión a ARN/genética , Proteína FUS de Unión a ARN/metabolismo , Femenino , Drosophila , Desarrollo de Músculos/fisiología , Persona de Mediana Edad , Anciano , Neuronas Motoras/metabolismo , Neuronas Motoras/patología , Mioblastos/metabolismo
2.
bioRxiv ; 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-39005355

RESUMEN

Neurogenesis and gliogenesis continue in the Ventricular-Subventricular Zone (V-SVZ) of the adult rodent brain. B1 cells are astroglial cells derived from radial glia that function as primary progenitors or neural stem cells (NSCs) in the V-SVZ. B1 cells, which have a small apical contact with the ventricle, decline in numbers during early postnatal life, yet neurogenesis continues into adulthood. Here we found that a second population of V-SVZ astroglial cells (B2 cells), that do not contact the ventricle, function as NSCs in the adult brain. B2 cell numbers increase postnatally, remain constant in 12-month-old mice and decrease by 18 months. Transcriptomic analysis of ventricular-contacting and non-contacting B cells revealed key molecular differences to distinguish B1 from B2 cells. Transplantation and lineage tracing of B2 cells demonstrate their function as primary progenitors for adult neurogenesis. This study reveals how NSC function is relayed from B1 to B2 progenitors to maintain adult neurogenesis.

3.
Oncotarget ; 15: 49-64, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38275289

RESUMEN

Oligodendrocyte precursor markers have become of great interest to identify new diagnostic and therapeutic targets for diffuse gliomas, since state-of-the-art studies point towards immature oligodendrocytes as a possible source of gliomagenesis. Brain enriched myelin associated protein 1 (BCAS1) is a novel marker of immature oligodendrocytes and was proposed to contribute to tumorigenesis in non-central nervous system tumors. However, BCAS1 role in diffuse glioma is still underexplored. This study analyzes the expression of BCAS1 in different tumor samples from patients with diffuse gliomas (17 oligodendrogliomas; 8 astrocytomas; 60 glioblastomas) and uncovers the molecular and ultrastructural features of BCAS1+ cells by immunostaining and electron microscopy. Our results show that BCAS1+ cells exhibit stellate or spherical morphology with similar ultrastructural features. Stellate and spherical cells were detected as isolated cells in all studied gliomas. Nevertheless, only stellate cells were found to be proliferative and formed tightly packed nodules with a highly proliferative rate in oligodendrogliomas. Our findings provide a comprehensive characterization of the BCAS1+ cell population within diffuse gliomas. The observed proliferative capacity and distribution of BCAS1+ stellate cells, particularly in oligodendrogliomas, highlight BCAS1 as an interesting marker, warranting further investigation into its role in tumor malignancy.


Asunto(s)
Astrocitoma , Neoplasias Encefálicas , Glioblastoma , Glioma , Oligodendroglioma , Humanos , Oligodendroglioma/patología , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Glioma/patología , Astrocitoma/patología , Glioblastoma/patología , Proteínas de Neoplasias
4.
Int J Mol Sci ; 24(19)2023 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-37834028

RESUMEN

Neurodegeneration with brain iron accumulation (NBIA) is a group of rare neurogenetic disorders frequently associated with iron accumulation in the basal nuclei of the brain. Among NBIA subtypes, ß-propeller protein-associated neurodegeneration (BPAN) is associated with mutations in the autophagy gene WDR45. The aim of this study was to demonstrate the autophagic defects and secondary pathological consequences in cellular models derived from two patients harboring WDR45 mutations. Both protein and mRNA expression levels of WDR45 were decreased in patient-derived fibroblasts. In addition, the increase of LC3B upon treatments with autophagy inducers or inhibitors was lower in mutant cells compared to control cells, suggesting decreased autophagosome formation and impaired autophagic flux. A transmission electron microscopy (TEM) analysis showed mitochondrial vacuolization associated with the accumulation of lipofuscin-like aggregates containing undegraded material. Autophagy dysregulation was also associated with iron accumulation and lipid peroxidation. In addition, mutant fibroblasts showed altered mitochondrial bioenergetics. Antioxidants such as pantothenate, vitamin E and α-lipoic prevented lipid peroxidation and iron accumulation. However, antioxidants were not able to correct the expression levels of WDR45, neither the autophagy defect nor cell bioenergetics. Our study demonstrated that WDR45 mutations in BPAN cellular models impaired autophagy, iron metabolism and cell bioenergetics. Antioxidants partially improved cell physiopathology; however, autophagy and cell bioenergetics remained affected.


Asunto(s)
Antioxidantes , Proteínas Portadoras , Humanos , Antioxidantes/farmacología , Antioxidantes/metabolismo , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Peroxidación de Lípido , Autofagia/genética , Hierro/metabolismo
5.
Biomed Pharmacother ; 167: 115518, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37717534

RESUMEN

Head and neck squamous cell carcinoma present a high mortality rate. Melatonin has been shown to have oncostatic effects in different types of cancers. However, inconsistent results have been reported for in vivo applications. Consequently, an alternative administration route is needed to improve bioavailability and establish the optimal dosage of melatonin for cancer treatment. On the other hand, the use of patient-derived tumor models has transformed the field of drug research because they reflect the heterogeneity of patient tumor tissues. In the present study, we explore mechanisms for increasing melatonin bioavailability in tumors and investigate its potential as an adjuvant to improve the therapeutic efficacy of cisplatin in the setting of both xenotransplanted cell lines and primary human HNSCC. We analyzed the effect of two different formulations of melatonin administered subcutaneously or intratumorally in Cal-27 and SCC-9 xenografts and in patient-derived xenografts. Melatonin effects on tumor mitochondrial metabolism was also evaluated as well as melatonin actions on tumor cell migration. In contrast to the results obtained with the subcutaneous melatonin, intratumoral injection of melatonin drastically inhibited tumor progression in HNSCC-derived xenografts, as well as in patient-derived xenografts. Interestingly, intratumoral injection of melatonin potentiated CDDP effects, decreasing Cal-27 tumor growth. We demonstrated that melatonin increases ROS production and apoptosis in tumors, targeting mitochondria. Melatonin also reduces migration capacities and metastasis markers. These results illustrate the great clinical potential of intratumoral melatonin treatment and encourage a future clinical trial in cancer patients to establish a proper clinical melatonin treatment.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Melatonina , Humanos , Carcinoma de Células Escamosas de Cabeza y Cuello/tratamiento farmacológico , Melatonina/farmacología , Melatonina/uso terapéutico , Carcinoma de Células Escamosas/patología , Xenoinjertos , Inyecciones Intralesiones , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Cisplatino/farmacología , Cisplatino/uso terapéutico , Línea Celular Tumoral , Estrés Oxidativo
6.
Biomaterials ; 294: 122003, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36736095

RESUMEN

The mammalian brain has very limited ability to regenerate lost neurons and recover function after injury. Promoting the migration of young neurons (neuroblasts) derived from endogenous neural stem cells using biomaterials is a new and promising approach to aid recovery of the brain after injury. However, the delivery of sufficient neuroblasts to distant injured sites is a major challenge because of the limited number of scaffold cells that are available to guide neuroblast migration. To address this issue, we have developed an amphiphilic peptide [(RADA)3-(RADG)] (mRADA)-tagged N-cadherin extracellular domain (Ncad-mRADA), which can remain in mRADA hydrogels and be injected into deep brain tissue to facilitate neuroblast migration. Migrating neuroblasts directly contacted the fiber-like Ncad-mRADA hydrogel and efficiently migrated toward an injured site in the striatum, a deep brain area. Furthermore, application of Ncad-mRADA to neonatal cortical brain injury efficiently promoted neuronal regeneration and functional recovery. These results demonstrate that self-assembling Ncad-mRADA peptides mimic both the function and structure of endogenous scaffold cells and provide a novel strategy for regenerative therapy.


Asunto(s)
Cadherinas , Células-Madre Neurales , Animales , Encéfalo , Neuronas , Péptidos , Mamíferos
7.
Fluids Barriers CNS ; 19(1): 58, 2022 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-35821139

RESUMEN

BACKGROUND: Glioblastoma (GBM) is the most aggressive and common type of primary brain tumor in adults. Tumor location plays a role in patient prognosis, with tumors proximal to the lateral ventricles (LVs) presenting with worse overall survival, increased expression of stem cell genes, and increased incidence of distal tumor recurrence. This may be due in part to interaction of GBM with factors of the subventricular zone (SVZ), including those contained within the cerebrospinal fluid (CSF). However, direct interaction of GBM tumors with CSF has not been proved and would be hindered in the presence of an intact ependymal cell layer. METHODS: Here, we investigate the ependymal cell barrier and its derived extracellular matrix (ECM) fractones in the vicinity of a GBM tumor. Patient-derived GBM cells were orthotopically implanted into immunosuppressed athymic mice in locations distal and proximal to the LV. A PBS vehicle injection in the proximal location was included as a control. At four weeks post-xenograft, brain tissue was examined for alterations in ependymal cell health via immunohistochemistry, scanning electron microscopy, and transmission electron microscopy. RESULTS: We identified local invading GBM cells within the LV wall and increased influx of CSF into the LV-proximal GBM tumor bulk compared to controls. In addition to the physical disruption of the ependymal cell barrier, we also identified increased signs of compromised ependymal cell health in LV-proximal tumor-bearing mice. These signs include increased accumulation of lipid droplets, decreased cilia length and number, and decreased expression of cell channel proteins. We additionally identified elevated numbers of small fractones in the SVZ within this group, suggesting increased indirect CSF-contained molecule signaling to tumor cells. CONCLUSIONS: Our data is the first to show that LV-proximal GBMs physically disrupt the ependymal cell barrier in animal models, resulting in disruptions in ependymal cell biology and increased CSF interaction with the tumor bulk. These findings point to ependymal cell health and CSF-contained molecules as potential axes for therapeutic targeting in the treatment of GBM.


Asunto(s)
Glioblastoma , Animales , Cilios , Epéndimo/metabolismo , Matriz Extracelular/patología , Glioblastoma/metabolismo , Humanos , Ventrículos Laterales/patología , Ratones
8.
Adv Healthc Mater ; 11(20): e2201203, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35856921

RESUMEN

Extracellular vesicles (EVs) are emerging as powerful players in cell-to-cell communication both in healthy and diseased brain. In Parkinson's disease (PD)-characterized by selective dopaminergic neuron death in ventral midbrain (VMB) and degeneration of their terminals in striatum (STR)-astrocytes exert dual harmful/protective functions, with mechanisms not fully elucidated. Here, this study shows that astrocytes from the VMB-, STR-, and VMB/STR-depleted brains release a population of small EVs  in a region-specific manner. Interestingly, VMB-astrocytes secreted the highest rate of EVs, which is further exclusively increased in response to CCL3, a chemokine that promotes robust dopaminergic neuroprotection in different PD models. The neuroprotective potential of nigrostriatal astrocyte-EVs is investigated in differentiated versus undifferentiated SH-SY5Y cells exposed to oxidative stress and mitochondrial toxicity. EVs from both VMB- and STR-astrocytes counteract H2 O2 -induced caspase-3 activation specifically in differentiated cells, with EVs from CCL3-treated astrocytes showing a higher protective effect. High resolution respirometry further reveals that nigrostriatal astrocyte-EVs rescue neuronal mitochondrial complex I function impaired by the neurotoxin MPP+ . Notably, only EVs from VMB-astrocyte fully restore ATP production, again specifically in differentiated SH-SY5Y. These results highlight a regional diversity in the nigrostriatal system for the secretion and activities of astrocyte-EVs, with neuroprotective implications for PD.


Asunto(s)
Vesículas Extracelulares , Neuroblastoma , Enfermedad de Parkinson , Humanos , Astrocitos/metabolismo , Enfermedad de Parkinson/metabolismo , Neurotoxinas/metabolismo , Neurotoxinas/farmacología , Caspasa 3/metabolismo , Neuroblastoma/metabolismo , Neuronas Dopaminérgicas/metabolismo , Mitocondrias , Muerte Celular , Vesículas Extracelulares/metabolismo , Dopamina/farmacología , Adenosina Trifosfato/metabolismo
9.
Science ; 375(6579): eabk2346, 2022 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-35084970

RESUMEN

The human cortex contains inhibitory interneurons derived from the medial ganglionic eminence (MGE), a germinal zone in the embryonic ventral forebrain. How this germinal zone generates sufficient interneurons for the human brain remains unclear. We found that the human MGE (hMGE) contains nests of proliferative neuroblasts with ultrastructural and transcriptomic features that distinguish them from other progenitors in the hMGE. When dissociated hMGE cells are transplanted into the neonatal mouse brain, they reform into nests containing proliferating neuroblasts that generate young neurons that migrate extensively into the mouse forebrain and mature into different subtypes of functional interneurons. Together, these results indicate that the nest organization and sustained proliferation of neuroblasts in the hMGE provide a mechanism for the extended production of interneurons for the human forebrain.


Asunto(s)
Interneuronas/fisiología , Eminencia Media/embriología , Células-Madre Neurales/fisiología , Neurogénesis , Prosencéfalo/citología , Animales , Animales Recién Nacidos , Movimiento Celular , Proliferación Celular , Corteza Cerebral/citología , Corteza Cerebral/embriología , Corteza Cerebral/crecimiento & desarrollo , Neuronas GABAérgicas/citología , Neuronas GABAérgicas/fisiología , Perfilación de la Expresión Génica , Edad Gestacional , Humanos , Interneuronas/citología , Eminencia Media/citología , Eminencia Media/crecimiento & desarrollo , Ratones , Células-Madre Neurales/trasplante , Prosencéfalo/embriología , Prosencéfalo/crecimiento & desarrollo , Trasplante Heterólogo
10.
Sci Rep ; 12(1): 1493, 2022 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-35087169

RESUMEN

The fusion protein of uncharacterised zinc finger translocation associated (ZFTA) and effector transcription factor of tumorigenic NF-κB signalling, RELA (ZFTA-RELA), is expressed in more than two-thirds of supratentorial ependymoma (ST-EPN-RELA), but ZFTA's expression profile and functional analysis in multiciliated ependymal (E1) cells have not been examined. Here, we showed the mRNA expression of mouse Zfta peaks on embryonic day (E) 17.5 in the wholemount of the lateral walls of the lateral ventricle. Zfta was expressed in the nuclei of FoxJ1-positive immature E1 (pre-E1) cells in E18.5 mouse embryonic brain. Interestingly, the transcription factors promoting ciliogenesis (ciliary TFs) (e.g., multicilin) and ZFTA-RELA upregulated luciferase activity using a 5' upstream sequence of ZFTA in cultured cells. Zftatm1/tm1 knock-in mice did not show developmental defects or abnormal fertility. In the Zftatm1/tm1 E1 cells, morphology, gene expression, ciliary beating frequency and ependymal flow were unaffected. These results suggest that Zfta is expressed in pre-E1 cells, possibly under the control of ciliary TFs, but is not essential for ependymal development or flow. This study sheds light on the mechanism of the ZFTA-RELA expression in the pathogenesis of ST-EPN-RELA: Ciliary TFs initiate ZFTA-RELA expression in pre-E1 cells, and ZFTA-RELA enhances its own expression using positive feedback.


Asunto(s)
Ependimoma
11.
Dev Cell ; 56(24): 3334-3348.e6, 2021 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-34932949

RESUMEN

Centrioles comprise the heart of centrosomes, microtubule-organizing centers. To study the function of centrioles in lung and gut development, we genetically disrupted centrioles throughout the mouse endoderm. Surprisingly, removing centrioles from the endoderm did not disrupt intestinal growth or development but blocked lung branching. In the lung, acentriolar SOX2-expressing airway epithelial cells apoptosed. Loss of centrioles activated p53, and removing p53 restored survival of SOX2-expressing cells, lung branching, and mouse viability. To investigate how endodermal p53 activation specifically killed acentriolar SOX2-expressing cells, we assessed ERK, a prosurvival cue. ERK was active throughout the intestine and in the distal lung buds, correlating with tolerance to centriole loss. Pharmacologically inhibiting ERK activated apoptosis in acentriolar cells, revealing that ERK activity protects acentriolar cells from apoptosis. Therefore, centrioles are largely dispensable for endodermal growth and the spatial distribution of ERK activity in the endoderm shapes the developmental consequences of centriolar defects and p53 activation.


Asunto(s)
Apoptosis , Centriolos/metabolismo , Endodermo/embriología , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Animales , Supervivencia Celular , Endodermo/metabolismo , Células Epiteliales/metabolismo , Intestinos/crecimiento & desarrollo , Pulmón/embriología , Ratones Endogámicos C57BL , Proteínas Asociadas a Microtúbulos/metabolismo , Morfogénesis , Factores de Transcripción SOXB1/metabolismo , Células Madre/metabolismo
12.
J Cell Biol ; 220(9)2021 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-34241634

RESUMEN

Cells inherit two centrioles, the older of which is uniquely capable of generating a cilium. Using proteomics and superresolved imaging, we identify a module that we term DISCO (distal centriole complex). The DISCO components CEP90, MNR, and OFD1 underlie human ciliopathies. This complex localizes to both distal centrioles and centriolar satellites, proteinaceous granules surrounding centrioles. Cells and mice lacking CEP90 or MNR do not generate cilia, fail to assemble distal appendages, and do not transduce Hedgehog signals. Disrupting the satellite pools does not affect distal appendage assembly, indicating that it is the centriolar populations of MNR and CEP90 that are critical for ciliogenesis. CEP90 recruits the most proximal known distal appendage component, CEP83, to root distal appendage formation, an early step in ciliogenesis. In addition, MNR, but not CEP90, restricts centriolar length by recruiting OFD1. We conclude that DISCO acts at the distal centriole to support ciliogenesis by restraining centriole length and assembling distal appendages, defects in which cause human ciliopathies.


Asunto(s)
Centriolos/metabolismo , Cilios/metabolismo , Ciliopatías/genética , Proteínas Asociadas a Microtúbulos/genética , Proteínas/genética , Animales , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Línea Celular , Centriolos/patología , Centriolos/ultraestructura , Cilios/patología , Cilios/ultraestructura , Ciliopatías/metabolismo , Ciliopatías/patología , Embrión de Mamíferos , Células Epiteliales/citología , Células Epiteliales/metabolismo , Regulación de la Expresión Génica , Genes Reporteros , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Proteínas Luminiscentes/genética , Proteínas Luminiscentes/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Asociadas a Microtúbulos/deficiencia , Proteínas Asociadas a Microtúbulos/metabolismo , Proteínas/metabolismo , Epitelio Pigmentado de la Retina/citología , Epitelio Pigmentado de la Retina/metabolismo , Transducción de Señal
14.
J Neurosci ; 38(19): 4598-4609, 2018 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-29661967

RESUMEN

In the rodent olfactory system, neuroblasts produced in the ventricular-subventricular zone of the postnatal brain migrate tangentially in chain-like cell aggregates toward the olfactory bulb (OB) through the rostral migratory stream (RMS). After reaching the OB, the chains are dissociated and the neuroblasts migrate individually and radially toward their final destination. The cellular and molecular mechanisms controlling cell-cell adhesion during this detachment remain unclear. Here we report that Fyn, a nonreceptor tyrosine kinase, regulates the detachment of neuroblasts from chains in the male and female mouse OB. By performing chemical screening and in vivo loss-of-function and gain-of-function experiments, we found that Fyn promotes somal disengagement from the chains and is involved in neuronal migration from the RMS into the granule cell layer of the OB. Fyn knockdown or Dab1 (disabled-1) deficiency caused p120-catenin to accumulate and adherens junction-like structures to be sustained at the contact sites between neuroblasts. Moreover, a Fyn and N-cadherin double-knockdown experiment indicated that Fyn regulates the N-cadherin-mediated cell adhesion between neuroblasts. These results suggest that the Fyn-mediated control of cell-cell adhesion is critical for the detachment of chain-forming neuroblasts in the postnatal OB.SIGNIFICANCE STATEMENT In the postnatal brain, newly born neurons (neuroblasts) migrate in chain-like cell aggregates toward their destination, where they are dissociated into individual cells and mature. The cellular and molecular mechanisms controlling the detachment of neuroblasts from chains are not understood. Here we show that Fyn, a nonreceptor tyrosine kinase, promotes the somal detachment of neuroblasts from chains, and that this regulation is critical for the efficient migration of neuroblasts to their destination. We further show that Fyn and Dab1 (disabled-1) decrease the cell-cell adhesion between chain-forming neuroblasts, which involves adherens junction-like structures. Our results suggest that Fyn-mediated regulation of the cell-cell adhesion of neuroblasts is critical for their detachment from chains in the postnatal brain.


Asunto(s)
Encéfalo/fisiología , Células-Madre Neurales/fisiología , Proteínas Proto-Oncogénicas c-fyn/fisiología , Animales , Encéfalo/citología , Encéfalo/crecimiento & desarrollo , Cadherinas/genética , Cateninas/metabolismo , Adhesión Celular/fisiología , Movimiento Celular/genética , Femenino , Técnicas de Silenciamiento del Gen , Masculino , Ratones , Proteínas del Tejido Nervioso/genética , Bulbo Olfatorio/citología , Bulbo Olfatorio/crecimiento & desarrollo , Bulbo Olfatorio/fisiología
15.
BMC Neurol ; 17(1): 173, 2017 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-28874134

RESUMEN

BACKGROUND: Adult neurogenesis persists through life at least in classic neurogenic niches. Neurogenesis has been previously described as reduced in neurodegenerative diseases. There is not much knowledge about is adult neurogenesis is or not modified in amyotrophy lateral sclerosis (ALS). All previous publications has studied the ALS SOD1 (superoxide dismutase) transgenic mouse model. The purpose of this study is to examine the process of adult neurogenesis in classic niches (subventricular zone [SVZ] and subgranular zone [SGZ] of the dentate gyrus) in patients with amyotrophic lateral sclerosis (ALS), both with (ALS-FTD) and without associated frontotemporal dementia (FTD). METHODS: We studied 9 autopsies of patients with ALS (including 2 with ALS-FTD) and 4 controls. ALS was confirmed histologically. Studies of the SVZ and SGZ were conducted using markers of proliferation (Ki-67, PCNA), of pluripotent neural progenitor cells (GFAPδ), neuroblasts (PSA-NCAM, DCX, TUJ1), and an astrocyte marker (GFAP). Results were analyzed with non-parametric tests. We then studied correlations between the different markers and the percentage of phosphorylated TDP-43 (pTDP-43). RESULTS: We observed a statistically significant increase in proliferation in the SVZ in all patients with ALS. While this increase was more marked in ALS forms associated with dementia, the small sample size does not permit a statistical subgroup analysis. In contrast, proliferation in the SGZ was decreased in all patients. These alterations showed a positive and direct correlation with the percentage of pTDP-43 in the SVZ, and a negative, exponential correlation with that percentage in the SGZ. CONCLUSIONS: We observed alterations of the proliferation of neural progenitor in classic adult neurogenic niches in patients with ALS. The 2 neurogenic niches exhibited opposite changes such that proliferation increased in the SVZ and decreased in the SGZ.


Asunto(s)
Esclerosis Amiotrófica Lateral/fisiopatología , Encéfalo/fisiopatología , Demencia Frontotemporal/fisiopatología , Anciano , Anciano de 80 o más Años , Encéfalo/patología , Proteína Doblecortina , Femenino , Humanos , Ventrículos Laterales , Masculino , Persona de Mediana Edad , Células-Madre Neurales/metabolismo , Neurogénesis/fisiología
16.
Stem Cell Reports ; 9(1): 203-216, 2017 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-28648897

RESUMEN

Neural stem cells (B1 astrocytes; NSCs) in the adult ventricular-subventricular-zone (V-SVZ) originate in the embryo. Surprisingly, recent work has shown that B1 cells remain largely quiescent. They are reactivated postnatally to function as primary progenitors for neurons destined for the olfactory bulb and some corpus callosum oligodendrocytes. The cellular and molecular properties of quiescent B1 cells remain unknown. Here we found that a subpopulation of B1 cells has a unique nuclear envelope invagination specialization similar to envelope-limited chromatin sheets (ELCS), reported in certain lymphocytes and some cancer cells. Using molecular markers, [3H]thymidine birth-dating, and Ara-C, we found that B1 cells with ELCS correspond to quiescent NSCs. ELCS begin forming in embryonic radial glia cells and represent a specific nuclear compartment containing particular epigenetic modifications and telomeres. These results reveal a unique nuclear compartment in quiescent NSCs, which is useful for identifying these primary progenitors and study their gene regulation.


Asunto(s)
Ventrículos Laterales/citología , Células-Madre Neurales/citología , Membrana Nuclear/ultraestructura , Células Madre Adultas/citología , Animales , Astrocitos/citología , Ciclo Celular , Células Cultivadas , Cromatina/química , Ratones
17.
Neurology ; 88(13): 1235-1242, 2017 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-28251919

RESUMEN

OBJECTIVE: To identify cell-surface antibodies in patients with neuromyotonia and to describe the main clinical implications. METHODS: Sera of 3 patients with thymoma-associated neuromyotonia and myasthenia gravis were used to immunoprecipitate and characterize neuronal cell-surface antigens using reported techniques. The clinical significance of antibodies against precipitated proteins was assessed with sera of 98 patients (neuromyotonia 46, myasthenia gravis 52, thymoma 42; 33 of them with overlapping syndromes) and 219 controls (other neurologic diseases, cancer, and healthy volunteers). RESULTS: Immunoprecipitation studies identified 3 targets, including the Netrin-1 receptors DCC (deleted in colorectal carcinoma) and UNC5A (uncoordinated-5A) as well as Caspr2 (contactin-associated protein-like 2). Cell-based assays with these antigens showed that among the indicated patients, 9 had antibodies against Netrin-1 receptors (7 with additional Caspr2 antibodies) and 5 had isolated Caspr2 antibodies. Only one of the 219 controls had isolated Caspr2 antibodies with relapsing myelitis episodes. Among patients with neuromyotonia and/or myasthenia gravis, the presence of Netrin-1 receptor or Caspr2 antibodies predicted thymoma (p < 0.05). Coexisting Caspr2 and Netrin-1 receptor antibodies were associated with concurrent thymoma, myasthenia gravis, and neuromyotonia, often with Morvan syndrome (p = 0.009). Expression of DCC, UNC5A, and Caspr2 proteins was demonstrated in paraffin-embedded thymoma samples (3) and normal thymus. CONCLUSIONS: Antibodies against Netrin-1 receptors (DCC and UNC5a) and Caspr2 often coexist and associate with thymoma in patients with neuromyotonia and myasthenia gravis. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that antibodies against Netrin-1 receptors can identify patients with thymoma (sensitivity 21.4%, specificity 100%).


Asunto(s)
Autoanticuerpos/sangre , Miastenia Gravis/sangre , Factores de Crecimiento Nervioso/inmunología , Factores de Crecimiento Nervioso/metabolismo , Timoma/sangre , Neoplasias del Timo/sangre , Proteínas Supresoras de Tumor/inmunología , Proteínas Supresoras de Tumor/metabolismo , Adulto , Anciano , Proteínas de Unión al Calcio , Moléculas de Adhesión Celular Neuronal/genética , Moléculas de Adhesión Celular Neuronal/metabolismo , Receptor DCC , Electromiografía , Femenino , Células HEK293 , Humanos , Inmunoprecipitación , Imagen por Resonancia Magnética , Masculino , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Persona de Mediana Edad , Músculo Esquelético/patología , Músculo Esquelético/fisiopatología , Miastenia Gravis/complicaciones , Miastenia Gravis/diagnóstico por imagen , Factores de Crecimiento Nervioso/genética , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Receptores de Netrina , Netrina-1 , Moléculas de Adhesión de Célula Nerviosa , Receptores de Superficie Celular/genética , Receptores de Superficie Celular/metabolismo , Timoma/complicaciones , Timoma/diagnóstico por imagen , Neoplasias del Timo/complicaciones , Neoplasias del Timo/diagnóstico por imagen , Transfección , Proteínas Supresoras de Tumor/genética
18.
Stem Cell Reports ; 7(3): 411-424, 2016 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-27594590

RESUMEN

The dermal Panniculus carnosus (PC) muscle is important for wound contraction in lower mammals and represents an interesting model of muscle regeneration due to its high cell turnover. The resident satellite cells (the bona fide muscle stem cells) remain poorly characterized. Here we analyzed PC satellite cells with regard to developmental origin and purported function. Lineage tracing shows that they originate in Myf5(+), Pax3/Pax7(+) cell populations. Skin and muscle wounding increased PC myofiber turnover, with the satellite cell progeny being involved in muscle regeneration but with no detectable contribution to the wound-bed myofibroblasts. Since hematopoietic stem cells fuse to PC myofibers in the absence of injury, we also studied the contribution of bone marrow-derived cells to the PC satellite cell compartment, demonstrating that cells of donor origin are capable of repopulating the PC muscle stem cell niche after irradiation and bone marrow transplantation but may not fully acquire the relevant myogenic commitment.


Asunto(s)
Células Satélite del Músculo Esquelético/citología , Células Satélite del Músculo Esquelético/metabolismo , Animales , Biomarcadores , Células de la Médula Ósea/citología , Células de la Médula Ósea/metabolismo , Técnicas de Cultivo de Célula , Diferenciación Celular , Linaje de la Célula , Proliferación Celular , Regulación del Desarrollo de la Expresión Génica , Ratones , Ratones Transgénicos , Desarrollo de Músculos , Músculo Esquelético/fisiología , Factor de Transcripción PAX3/genética , Factor de Transcripción PAX7/genética , Fenotipo , Regeneración , Células Satélite del Músculo Esquelético/trasplante
19.
J Neuroimmunol ; 297: 98-102, 2016 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-27397082

RESUMEN

We aimed to identify new cell-membrane antigens implicated in opsoclonus-myoclonus with neuroblastoma. The sera of 3 out of 14 patients showed IgG electron-microscopy immunogold reactivity on SH-SY5Y neuroblastoma cells. Immunoprecipitation experiments using rat brain synaptosomes and SH-SY5Y cells led to the identification of: (1) thirty-one nuclear/cytoplasmic proteins (including antigens HuB, HuC); (2) seven neuronal membrane proteins, including the Shaw-potassium channel Kv3.3 (KCNC3), whose genetic disruption in mice causes ataxia and generalized muscle twitching. Although cell-based assays did not demonstrate direct antigenicity, our findings point to Shaw-related subfamily of the potassium voltage-gated channels complexed proteins as hypothetical antigenic targets.


Asunto(s)
Neoplasias Encefálicas , Sistema Nervioso Central/metabolismo , Neuroblastoma , Síndrome de Opsoclonía-Mioclonía , Animales , Neoplasias Encefálicas/complicaciones , Neoplasias Encefálicas/inmunología , Neoplasias Encefálicas/patología , Moléculas de Adhesión Celular Neuronal/metabolismo , Línea Celular Tumoral , Sistema Nervioso Central/ultraestructura , Niño , Bases de Datos Factuales/estadística & datos numéricos , Encefalitis/complicaciones , Encefalitis/inmunología , Femenino , Células HEK293 , Humanos , Masculino , Proteínas de la Membrana/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Proteínas del Tejido Nervioso/ultraestructura , Neuroblastoma/complicaciones , Neuroblastoma/inmunología , Neuroblastoma/patología , Proteínas Nucleares/metabolismo , Proteínas Nucleares/ultraestructura , Síndrome de Opsoclonía-Mioclonía/complicaciones , Síndrome de Opsoclonía-Mioclonía/inmunología , Síndrome de Opsoclonía-Mioclonía/patología , Ratas , Ratas Wistar , Canales de Potasio Shaw/inmunología , Canales de Potasio Shaw/metabolismo , Canales de Potasio Shaw/ultraestructura , Sinaptosomas/metabolismo , Sinaptosomas/ultraestructura , Timoma/complicaciones
20.
Stem Cell Res ; 16(2): 387-96, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26921873

RESUMEN

Radiation therapy is a standard treatment for brain tumor patients. However, it comes with side effects, such as neurological deficits. While likely multi-factorial, the effect may in part be associated with the impact of radiation on the neurogenic niches. In the adult mammalian brain, the neurogenic niches are localized in the subventricular zone (SVZ) of the lateral ventricles and the dentate gyrus of the hippocampus, where the neural stem cells (NSCs) reside. Several reports showed that radiation produces a drastic decrease in the proliferative capacity of these regions, which is related to functional decline. In particular, radiation to the SVZ led to a reduced long-term olfactory memory and a reduced capacity to respond to brain damage in animal models, as well as compromised tumor outcomes in patients. By contrast, other studies in humans suggested that increased radiation dose to the SVZ may be associated with longer progression-free survival in patients with high-grade glioma. In this review, we summarize the cellular and functional effects of irradiating the SVZ niche. In particular, we review the pros and cons of using radiation during brain tumor treatment, discussing the complex relationship between radiation dose to the SVZ and both tumor control and toxicity.


Asunto(s)
Ventrículos Laterales/citología , Células-Madre Neurales/citología , Animales , Encéfalo/efectos de la radiación , Carcinogénesis , Humanos , Células-Madre Neurales/metabolismo , Nicho de Células Madre
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