Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
1.
Nature ; 604(7907): 740-748, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35444273

RESUMEN

All tissue-resident macrophages of the central nervous system (CNS)-including parenchymal microglia, as well as CNS-associated macrophages (CAMs1) such as meningeal and perivascular macrophages2-7-are part of the CNS endogenous innate immune system that acts as the first line of defence during infections or trauma2,8-10. It has been suggested that microglia and all subsets of CAMs are derived from prenatal cellular sources in the yolk sac that were defined as early erythromyeloid progenitors11-15. However, the precise ontogenetic relationships, the underlying transcriptional programs and the molecular signals that drive the development of distinct CAM subsets in situ are poorly understood. Here we show, using fate-mapping systems, single-cell profiling and cell-specific mutants, that only meningeal macrophages and microglia share a common prenatal progenitor. By contrast, perivascular macrophages originate from perinatal meningeal macrophages only after birth in an integrin-dependent manner. The establishment of perivascular macrophages critically requires the presence of arterial vascular smooth muscle cells. Together, our data reveal a precisely timed process in distinct anatomical niches for the establishment of macrophage subsets in the CNS.


Asunto(s)
Linaje de la Célula , Sistema Nervioso Central , Macrófagos , Sistema Nervioso Central/inmunología , Femenino , Humanos , Inmunidad Innata , Macrófagos/citología , Microglía , Embarazo , Saco Vitelino
2.
Immunity ; 48(3): 514-529.e6, 2018 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-29548672

RESUMEN

Microglia as tissue macrophages contribute to the defense and maintenance of central nervous system (CNS) homeostasis. Little is known about the epigenetic signals controlling microglia function in vivo. We employed constitutive and inducible mutagenesis in microglia to delete two class I histone deacetylases, Hdac1 and Hdac2. Prenatal ablation of Hdac1 and Hdac2 impaired microglial development. Mechanistically, the promoters of pro-apoptotic and cell cycle genes were hyperacetylated in absence of Hdac1 and Hdac2, leading to increased apoptosis and reduced survival. In contrast, Hdac1 and Hdac2 were not required for adult microglia survival during homeostasis. In a mouse model of Alzheimer's disease, deletion of Hdac1 and Hdac2 in microglia, but not in neuroectodermal cells, resulted in a decrease in amyloid load and improved cognitive impairment by enhancing microglial amyloid phagocytosis. Collectively, we report a role for epigenetic factors that differentially affect microglia development, homeostasis, and disease that could potentially be utilized therapeutically.


Asunto(s)
Histona Desacetilasa 1/genética , Histona Desacetilasa 2/genética , Homeostasis , Microglía/inmunología , Microglía/metabolismo , Enfermedades Neurodegenerativas/genética , Neurogénesis/genética , Animales , Apoptosis , Proliferación Celular , Modelos Animales de Enfermedad , Epigénesis Genética , Expresión Génica , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Histona Desacetilasa 1/metabolismo , Histona Desacetilasa 2/metabolismo , Histonas/metabolismo , Trastornos de la Memoria/genética , Trastornos de la Memoria/metabolismo , Ratones , Ratones Noqueados , Ratones Transgénicos , Enfermedades Neurodegenerativas/metabolismo , Enfermedades Neurodegenerativas/patología , Enfermedades Neurodegenerativas/psicología , Neurogénesis/inmunología , Fagocitosis/inmunología , Placa Amiloide/genética , Placa Amiloide/metabolismo , Placa Amiloide/patología , Aprendizaje Espacial , Transcriptoma
3.
Eur J Immunol ; 53(10): e2250234, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37505465

RESUMEN

Experimental autoimmune encephalomyelitis (EAE) is an animal model of central nervous system (CNS) autoimmunity. It is most commonly used to mimic aspects of multiple sclerosis (MS), a demyelinating disorder of the human brain and spinal cord. The innate immune response displays one of the core pathophysiological features linked to both the acute and chronic stages of MS. Hence, understanding and targeting the innate immune response is essential. Microglia and other CNS resident MUs, as well as infiltrating myeloid cells, diverge substantially in terms of both their biology and their roles in EAE. Recent advances in the field show that antigen presentation, as well as disease-propagating and regulatory interactions with lymphocytes, can be attributed to specific myeloid cell types and cell states in EAE lesions, following a distinct temporal pattern during disease initiation, propagation and recovery. Furthermore, single-cell techniques enable the assessment of characteristic proinflammatory as well as beneficial cell states, and identification of potential treatment targets. Here, we discuss the principles of EAE induction and protocols for varying experimental paradigms, the composition of the myeloid compartment of the CNS during health and disease, and systematically review effects on myeloid cells for therapeutic approaches in EAE.


Asunto(s)
Encefalomielitis Autoinmune Experimental , Esclerosis Múltiple , Animales , Humanos , Ratones , Sistema Nervioso Central , Esclerosis Múltiple/patología , Médula Espinal , Células Mieloides/metabolismo , Ratones Endogámicos C57BL
5.
Brain Sci ; 14(7)2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39061463

RESUMEN

Major depressive disorder (MDD) is prevalent with a high subjective and socio-economic burden. Despite the effectiveness of classical treatment methods, 20-30% of patients stay treatment-resistant. Deep Brain Stimulation of the superolateral branch of the medial forebrain bundle is emerging as a clinical treatment. The stimulation region (ventral tegmental area, VTA), supported by experimental data, points to the role of dopaminergic (DA) transmission in disease pathology. This work sets out to develop a workflow that will allow the performance of analyses on midbrain DA-ergic neurons and projections in subjects who have committed suicide. Human midbrains were retrieved during autopsy, formalin-fixed, and scanned in a Bruker MRI scanner (7T). Sections were sliced, stained for tyrosine hydroxylase (TH), digitized, and integrated into the Montreal Neurological Institute (MNI) brain space together with a high-resolution fiber tract atlas. Subnuclei of the VTA region were identified. TH-positive neurons and fibers were semi-quantitatively evaluated. The study established a rigorous protocol allowing for parallel histological assessments and fiber tractographic analysis in a common space. Semi-quantitative readings are feasible and allow the detection of cell loss in VTA subnuclei. This work describes the intricate workflow and first results of an investigation of DA anatomy in VTA subnuclei in a growing naturalistic database.

6.
Cell Rep ; 42(9): 113031, 2023 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-37635351

RESUMEN

Cre/loxP technology has revolutionized genetic studies and allowed for spatial and temporal control of gene expression in specific cell types. Microglial biology has particularly benefited because microglia historically have been difficult to transduce with virus or electroporation methods for gene delivery. Here, we investigate five of the most widely available microglial inducible Cre lines. We demonstrate varying degrees of recombination efficiency, cell-type specificity, and spontaneous recombination, depending on the Cre line and inter-loxP distance. We also establish best practice guidelines and protocols to measure recombination efficiency, particularly in microglia. There is increasing evidence that microglia are key regulators of neural circuits and major drivers of a broad range of neurological diseases. Reliable manipulation of their function in vivo is of utmost importance. Identifying caveats and benefits of all tools and implementing the most rigorous protocols are crucial to the growth of the field and the development of microglia-based therapeutics.


Asunto(s)
Integrasas , Microglía , Animales , Ratones , Microglía/metabolismo , Integrasas/metabolismo , Técnicas de Transferencia de Gen , Ratones Transgénicos
7.
Nat Neurosci ; 26(7): 1218-1228, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37386131

RESUMEN

Axonal degeneration determines the clinical outcome of multiple sclerosis and is thought to result from exposure of denuded axons to immune-mediated damage. Therefore, myelin is widely considered to be a protective structure for axons in multiple sclerosis. Myelinated axons also depend on oligodendrocytes, which provide metabolic and structural support to the axonal compartment. Given that axonal pathology in multiple sclerosis is already visible at early disease stages, before overt demyelination, we reasoned that autoimmune inflammation may disrupt oligodendroglial support mechanisms and hence primarily affect axons insulated by myelin. Here, we studied axonal pathology as a function of myelination in human multiple sclerosis and mouse models of autoimmune encephalomyelitis with genetically altered myelination. We demonstrate that myelin ensheathment itself becomes detrimental for axonal survival and increases the risk of axons degenerating in an autoimmune environment. This challenges the view of myelin as a solely protective structure and suggests that axonal dependence on oligodendroglial support can become fatal when myelin is under inflammatory attack.


Asunto(s)
Encefalomielitis Autoinmune Experimental , Esclerosis Múltiple , Ratones , Animales , Humanos , Vaina de Mielina/metabolismo , Axones/metabolismo , Esclerosis Múltiple/patología , Encefalomielitis Autoinmune Experimental/patología , Factores de Riesgo
8.
J Neurosurg ; 137(6): 1639-1649, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-35535829

RESUMEN

OBJECTIVE: The management of asymptomatic intracranial meningiomas is controversial. Through the assessment of growth predictors, the authors aimed to create the basis for practicable clinical pathways for the management of these tumors. METHODS: The authors volumetrically analyzed meningiomas radiologically diagnosed at their institution between 2003 and 2015. The primary endpoint was growth of tumor volume. The authors used significant variables from the multivariable regression model to construct a decision tree based on the exhaustive Chi-Square Automatic Interaction Detection (CHAID) algorithm. RESULTS: Of 240 meningiomas, 159 (66.3%) demonstrated growth during a mean observation period of 46.9 months. On multivariable logistic regression analysis, older age (OR 0.979 [95% CI 0.958-1.000], p = 0.048) and presence of calcification (OR 0.442 [95% CI 0.224-0.872], p = 0.019) had a negative predictive value for tumor growth, while T2-signal iso-/hyperintensity (OR 4.415 [95% CI 2.056-9.479], p < 0.001) had a positive predictive value. A decision tree model yielded three growth risk groups based on T2 signal intensity and presence of calcifications. The median tumor volume doubling time (Td) was 185.7 months in the low-risk, 100.1 months in the intermediate-risk, and 51.7 months in the high-risk group (p < 0.001). Whereas 0% of meningiomas in the low- and intermediate-risk groups had a Td of ≤ 12 months, the percentage was 8.9% in the high-risk group (p = 0.021). CONCLUSIONS: Most meningiomas demonstrated growth during follow-up. The absence of calcifications and iso-/hyperintensity on T2-weighted imaging offer a practical way of stratifying meningiomas as low, intermediate, or high risk. Small tumors in the low- or intermediate-risk categories can be monitored with longer follow-up intervals.


Asunto(s)
Calcinosis , Neoplasias Meníngeas , Meningioma , Humanos , Meningioma/patología , Neoplasias Meníngeas/patología , Estudios de Seguimiento , Carga Tumoral , Imagen por Resonancia Magnética , Estudios Retrospectivos
9.
Cell Metab ; 33(11): 2260-2276.e7, 2021 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-34731656

RESUMEN

As tissue macrophages of the central nervous system (CNS), microglia constitute the pivotal immune cells of this organ. Microglial features are strongly dependent on environmental cues such as commensal microbiota. Gut bacteria are known to continuously modulate microglia maturation and function by the production of short-chain fatty acids (SCFAs). However, the precise mechanism of this crosstalk is unknown. Here we determined that the immature phenotype of microglia from germ-free (GF) mice is epigenetically imprinted by H3K4me3 and H3K9ac on metabolic genes associated with substantial functional alterations including increased mitochondrial mass and specific respiratory chain dysfunctions. We identified acetate as the essential microbiome-derived SCFA driving microglia maturation and regulating the homeostatic metabolic state, and further showed that it is able to modulate microglial phagocytosis and disease progression during neurodegeneration. These findings indicate that acetate is an essential bacteria-derived molecule driving metabolic pathways and functions of microglia during health and perturbation.


Asunto(s)
Microbiota , Acetatos/farmacología , Animales , Encéfalo/metabolismo , Ácidos Grasos Volátiles/metabolismo , Sistema Inmunológico/metabolismo , Ratones , Microbiota/fisiología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA