RESUMEN
Both resident innate and peripheral immune aberrations have been demonstrated to influence Parkinson's disease (PD) progression. However, it is still enigmatic how and which immune components are lethal to the dopaminergic neuron in PD. We now show that levels of perforin, a pore-forming protein expressed in cytotoxic immune cells, was significantly increased in the serum of wild-type mice 4 weeks after injection of MPTP, a toxin used to induce PD-like symptoms. We demonstrate that perforin-deficiency attenuated the acute striatal dopamine reduction by 33%, ablated microglia activation 3 days post MPTP-injection; and retarded dopaminergic neuron death 4 weeks post MPTP-injection. Our study suggests that perforin plays a role in dopaminergic neuron loss in PD.
Asunto(s)
Cuerpo Estriado/metabolismo , Neuronas Dopaminérgicas/metabolismo , Neuronas Dopaminérgicas/patología , Trastornos Parkinsonianos/metabolismo , Trastornos Parkinsonianos/patología , Perforina/metabolismo , Animales , Células Cultivadas , Cuerpo Estriado/patología , Masculino , Ratones , Ratones Endogámicos C57BLRESUMEN
Many germ cells are eliminated during development, long before oogenesis or spermatogenesis. In mouse fetal testes, the majority of germ cell apoptosis coincides with the onset of male differentiation, suggesting coordination of these processes. We studied fetal germ-cell fates and discovered that both apoptosis and differentiation initiate in clonally related clusters. Lineage tracing confirmed that germ cells die as clones independent of intercellular bridges, suggesting that shared intrinsic properties are apoptotic determinants. We identified transcriptional heterogeneity among fetal germ cells that included an apoptosis-susceptible population characterized by failure to differentiate, whereas successful differentiation to prospermatogonia occurred through the expression of epigenetically regulated genes, including LINE1. Our results indicate that the fetal germ-cell fate is based on discrete cell-heritable identities. Elevated DNA methylation in the apoptosis-susceptible subpopulation supports our hypothesis that earlier errors in germ-cell epigenetic reprogramming derail differentiation in cellular progeny, leading to fetal apoptotic selection that ultimately improves the gamete quality.
Asunto(s)
Apoptosis/genética , Diferenciación Celular/genética , Células Clonales/metabolismo , Células Germinativas/metabolismo , Espermatogénesis/genética , Testículo/metabolismo , Animales , Metilación de ADN , Perfilación de la Expresión Génica/métodos , Regulación del Desarrollo de la Expresión Génica , Ontología de Genes , Masculino , Ratones de la Cepa 129 , Ratones Noqueados , Ratones Transgénicos , Testículo/citología , Testículo/embriologíaRESUMEN
Neuronal degeneration within the substantia nigra and the loss of the dopaminergic nigro-striatal pathway are the major hallmarks of Parkinson's disease (PD). Grafts of foetal ventral mesencephalic (VM) dopaminergic (DA) neurons into the striatum have been shown to be able to restore striatal dopamine levels and to improve overall PD symptoms. However, human foetus-derived cell grafts are not feasible for clinical application. Autologous induced pluripotent stem cell (iPS cell)-derived DA neurons are emerging as an unprecedented alternative. In this review, we summarize and compare the efficacy of human iPS cell-derived DA neuron grafts to restore normal behaviour in a rat model for PD with that of human foetal primary DA neurons. The differences we observed in the efficacy to restore normal function between the 2 types of DA neuron grafts could be ascribed to intrinsic properties of the iPS cell-derived DA neurons that critically affected survival and proper neurite extension in the striatum after implantation.
Asunto(s)
Neuronas Dopaminérgicas/trasplante , Supervivencia de Injerto/fisiología , Células Madre Pluripotentes Inducidas/metabolismo , Neostriado/metabolismo , Enfermedad de Parkinson Secundaria/terapia , Animales , Diferenciación Celular , Supervivencia Celular , Dopamina/metabolismo , Neuronas Dopaminérgicas/citología , Neuronas Dopaminérgicas/metabolismo , Feto , Humanos , Células Madre Pluripotentes Inducidas/citología , Inyecciones Intralesiones , Neostriado/patología , Oxidopamina , Enfermedad de Parkinson Secundaria/inducido químicamente , Enfermedad de Parkinson Secundaria/metabolismo , Enfermedad de Parkinson Secundaria/patología , Cultivo Primario de Células , Ratas , Trasplante HeterólogoRESUMEN
Intrastriatal transplantation of dopaminergic neurons has been shown to be a potentially very effective therapeutic approach for the treatment of Parkinson's disease (PD). With the detection of induced pluripotent stem cells (iPSCs), an unlimited source of autologous dopaminergic (DA) neurons became available. Although the iPSC-derived dopaminergic neurons exhibited most of the fundamental dopaminergic characteristics, detailed analysis and comparison with primary DA neurons have shown some aberrations in the expression of genes involved in neuronal development and neurite outgrowth. The limited outgrowth of the iPSC-derived DA neurons may hamper their potential application in cell transplantation therapy for PD. In the present study, we examined whether the forced expression of L1 cell adhesion molecule (L1CAM) and polysialylated neuronal cell adhesion molecule (PSA-NCAM), via gene transduction, can promote the neurite formation and outgrowth of iPSC-derived DA neurons. In cultures on astrocyte layers, both adhesion factors significantly increased neurite formation of the adhesion factor overexpressing iPSC-derived DA neurons in comparison to control iPSC-derived DA neurons. The same tendency was observed when the DA neurons were plated on postnatal organotypic striatal slices; however, this effect did not reach statistical significance. Next, we examined the neurite outgrowth of the L1CAM- or PSA-NCAM-overexpressing iPSC-derived DA neurons after implantation in the striatum of unilaterally 6-hydroxydopamine (6-OHDA)-lesioned rats, the animal model for PD. Like the outgrowth on the organotypic striatal slices, no significant L1CAM- and PSA-NCAM-enforced neurite outgrowth of the implanted DA neurons was observed. Apparently, induced expression of L1CAM or PSA-NCAM in the iPSC-derived DA neurons cannot completely restore the neurite outgrowth potential that was reduced in these DA neurons as a consequence of epigenetic aberrations resulting from the iPSC reprogramming process.
Asunto(s)
Cuerpo Estriado/metabolismo , Neuronas Dopaminérgicas , Células Madre Pluripotentes Inducidas , Molécula L1 de Adhesión de Célula Nerviosa/metabolismo , Neuritas/metabolismo , Ácidos Siálicos/metabolismo , Trasplante de Células Madre , Animales , Neuronas Dopaminérgicas/metabolismo , Neuronas Dopaminérgicas/trasplante , Femenino , Xenoinjertos , Células Madre Pluripotentes Inducidas/metabolismo , Células Madre Pluripotentes Inducidas/trasplante , Ratones , Ratas , Ratas Sprague-DawleyRESUMEN
Carbon storage is affected by photosynthesis (Pn) and soil respiration (Rs), which have been studied extensively in natural and agricultural systems. However, the effects of Pn and Rs on carbon storages in the presence of arbuscular mycorrhizal fungi (AMF) in coalfields remain unclear. A field experiment was established in 2014 in Shendong coal mining subsidence area. The treatments comprised two inoculation levels (inoculated with or without 100 g AMF inoculums per seedlings) and four plant species [wild cherry (Prunus discadenia Koebne L.), cerasus humilis (Prunus dictyneura Diels L.), shiny leaf Yellow horn (Xanthoceras sorbifolium Bunge L.) and apricot (Armeniaca sibirica L.)]. AMF increased Pn of four species ranging from 15.3% to 33.1% and carbon storage, averaged by 17.2% compared to controls. Soil organic carbon (OC), easily extractable glomalin-relation soil protein (EE-GRSP), and total glomalin-relation soil protein (T-GRSP) were significantly increased by AMF treatment. The effect of AMF on the sensitivity of Rs depended on soil temperature. The results highlighted the exponential models to explain the responses of Rs to soil temperature, and for the first time quantified AMF caused carbon sequestration and Rs. Thus, to our knowledge, AMF is beneficial to ecosystems through facilitating carbon conservation in coalfield soils.
Asunto(s)
Carbón Mineral , Micorrizas/crecimiento & desarrollo , Árboles/crecimiento & desarrollo , Biodegradación Ambiental , ChinaRESUMEN
Microbially enhanced coalbed methane technology must be used to increase the methane content in mining and generate secondary biogenic gas. In this technology, the metabolic processes of methanogenic consortia are the basis for the production of biomethane from some of the organic compounds in coal. Thus, culture nutrition plays an important role in remediating the nutritional deficiency of a coal seam. To enhance the methane production rates for microorganism consortia, different types of nutrition solutions were examined in this study. Emulsion nutrition solutions containing a novel nutritional supplement, called dystrophy optional modification latex, increased the methane yield for methanogenic consortia. This new nutritional supplement can help methanogenic consortia form an enhanced anaerobic environment, optimize the microbial balance in the consortia, and improve the methane biosynthesis rate.
Asunto(s)
Archaea/metabolismo , Carbón Mineral , Fermentación , Metano/metabolismo , Medios de Cultivo , Emulsiones , Concentración de Iones de Hidrógeno , IllinoisRESUMEN
Induced pluripotent stem cells (iPSCs) hold great promise for in vitro generation of disease-relevant cell types, such as mesodiencephalic dopaminergic (mdDA) neurons involved in Parkinson's disease. Although iPSC-derived midbrain DA neurons have been generated, detailed genetic and epigenetic characterizations of such neurons are lacking. The goal of this study was to examine the authenticity of iPSC-derived DA neurons obtained by established protocols. We FACS purified mdDA (Pitx3 (Gfp/+) ) neurons derived from mouse iPSCs and primary mdDA (Pitx3 (Gfp/+) ) neurons to analyze and compare their genetic and epigenetic features. Although iPSC-derived DA neurons largely adopted characteristics of their in vivo counterparts, relevant deviations in global gene expression and DNA methylation were found. Hypermethylated genes, mainly involved in neurodevelopment and basic neuronal functions, consequently showed reduced expression levels. Such abnormalities should be addressed because they might affect unambiguous long-term functionality and hamper the potential of iPSC-derived DA neurons for in vitro disease modeling or cell-based therapy.
Asunto(s)
Neuronas Dopaminérgicas/citología , Neuronas Dopaminérgicas/metabolismo , Epigénesis Genética , Células Madre Pluripotentes Inducidas/citología , Células Madre Pluripotentes Inducidas/metabolismo , Transcriptoma , Animales , Biomarcadores , Metilación de ADN , Expresión Génica , Perfilación de la Expresión Génica , Ratones , Ratones Transgénicos , Especificidad de Órganos/genéticaRESUMEN
Recombinant adeno-associated virus (AAV) vectors are promising tools for gene therapy. In spinal cord injury where extensive damage occurs, vectors with high diffusion and transduction abilities are required. We compared the diffusion capacity and transduction efficiency of AAV2 and AAV5 vectors using a mouse spinal cord injury model. Our study demonstrates that AAV5 is more effective than AAV2 for delivering genes into the injured spinal cord tissue. AAV5 diffused 6.9 mm from the injection site, transduced with an approximately two-fold increase in total cell number and yielded an approximately three-fold increase in gene expression in comparison with AAV2.