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1.
Immunity ; 54(11): 2531-2546.e5, 2021 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-34644537

RESUMEN

Alternatively activated macrophages (AAMs) contribute to the resolution of inflammation and tissue repair. However, molecular pathways that govern their differentiation have remained incompletely understood. Here, we show that uncoupling protein-2-mediated mitochondrial reprogramming and the transcription factor GATA3 specifically controlled the differentiation of pro-resolving AAMs in response to the alarmin IL-33. In macrophages, IL-33 sequentially triggered early expression of pro-inflammatory genes and subsequent differentiation into AAMs. Global analysis of underlying signaling events revealed that IL-33 induced a rapid metabolic rewiring of macrophages that involved uncoupling of the respiratory chain and increased production of the metabolite itaconate, which subsequently triggered a GATA3-mediated AAM polarization. Conditional deletion of GATA3 in mononuclear phagocytes accordingly abrogated IL-33-induced differentiation of AAMs and tissue repair upon muscle injury. Our data thus identify an IL-4-independent and GATA3-dependent pathway in mononuclear phagocytes that results from mitochondrial rewiring and controls macrophage plasticity and the resolution of inflammation.


Asunto(s)
Metabolismo Energético , Inflamación/inmunología , Inflamación/metabolismo , Interleucina-33/metabolismo , Activación de Macrófagos/inmunología , Macrófagos/inmunología , Macrófagos/metabolismo , Biomarcadores , Diferenciación Celular/genética , Diferenciación Celular/inmunología , Inflamación/etiología , Activación de Macrófagos/genética , Mitocondrias/genética , Mitocondrias/inmunología , Mitocondrias/metabolismo , Fagocitos , Transducción de Señal
2.
Immunity ; 54(5): 1002-1021.e10, 2021 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-33761330

RESUMEN

Arthritis typically involves recurrence and progressive worsening at specific predilection sites, but the checkpoints between remission and persistence remain unknown. Here, we defined the molecular and cellular mechanisms of this inflammation-mediated tissue priming. Re-exposure to inflammatory stimuli caused aggravated arthritis in rodent models. Tissue priming developed locally and independently of adaptive immunity. Repeatedly stimulated primed synovial fibroblasts (SFs) exhibited enhanced metabolic activity inducing functional changes with intensified migration, invasiveness and osteoclastogenesis. Meanwhile, human SF from patients with established arthritis displayed a similar primed phenotype. Transcriptomic and epigenomic analyses as well as genetic and pharmacological targeting demonstrated that inflammatory tissue priming relies on intracellular complement C3- and C3a receptor-activation and downstream mammalian target of rapamycin- and hypoxia-inducible factor 1α-mediated metabolic SF invigoration that prevents activation-induced senescence, enhances NLRP3 inflammasome activity, and in consequence sensitizes tissue for inflammation. Our study suggests possibilities for therapeutic intervention abrogating tissue priming without immunosuppression.


Asunto(s)
Proteínas del Sistema Complemento/inmunología , Fibroblastos/inmunología , Inflamación/inmunología , Membrana Sinovial/inmunología , Inmunidad Adaptativa/inmunología , Animales , Artritis Reumatoide/inmunología , Línea Celular , Perros , Humanos , Mediadores de Inflamación/inmunología , Células de Riñón Canino Madin Darby , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Ratones SCID , Ratas Wistar , Transducción de Señal/inmunología
3.
PLoS Biol ; 20(2): e3001550, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35120120

RESUMEN

[This corrects the article DOI: 10.1371/journal.pbio.3000301.].

4.
Nature ; 572(7771): 670-675, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31391580

RESUMEN

Macrophages are considered to contribute to chronic inflammatory diseases such as rheumatoid arthritis1. However, both the exact origin and the role of macrophages in inflammatory joint disease remain unclear. Here we use fate-mapping approaches in conjunction with three-dimensional light-sheet fluorescence microscopy and single-cell RNA sequencing to perform a comprehensive spatiotemporal analysis of the composition, origin and differentiation of subsets of macrophages within healthy and inflamed joints, and study the roles of these macrophages during arthritis. We find that dynamic membrane-like structures, consisting of a distinct population of CX3CR1+ tissue-resident macrophages, form an internal immunological barrier at the synovial lining and physically seclude the joint. These barrier-forming macrophages display features that are otherwise typical of epithelial cells, and maintain their numbers through a pool of locally proliferating CX3CR1- mononuclear cells that are embedded into the synovial tissue. Unlike recruited monocyte-derived macrophages, which actively contribute to joint inflammation, these epithelial-like CX3CR1+ lining macrophages restrict the inflammatory reaction by providing a tight-junction-mediated shield for intra-articular structures. Our data reveal an unexpected functional diversification among synovial macrophages and have important implications for the general role of macrophages in health and disease.


Asunto(s)
Articulaciones/citología , Macrófagos/citología , Macrófagos/fisiología , Membrana Sinovial/citología , Sinoviocitos/citología , Sinoviocitos/fisiología , Uniones Estrechas/fisiología , Animales , Artritis/inmunología , Artritis/patología , Receptor 1 de Quimiocinas CX3C/análisis , Receptor 1 de Quimiocinas CX3C/metabolismo , Rastreo Celular , Femenino , Perfilación de la Expresión Génica , Humanos , Inflamación/inmunología , Inflamación/patología , Articulaciones/patología , Macrófagos/clasificación , Macrófagos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Análisis de Componente Principal , RNA-Seq , Análisis de la Célula Individual , Sinoviocitos/clasificación , Sinoviocitos/metabolismo , Transcriptoma/genética
5.
J Am Chem Soc ; 146(8): 5305-5315, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38325811

RESUMEN

The reversible condensation of catechols and boronic acids to boronate esters is a paradigm reaction in dynamic covalent chemistry. However, facile backward hydrolysis is detrimental for stability and has so far prevented applications for boronate-based materials. Here, we introduce cubic boronate ester cages 6 derived from hexahydroxy tribenzotriquinacenes and phenylene diboronic acids with ortho-t-butyl substituents. Due to steric shielding, dynamic exchange at the Lewis acidic boron sites is feasible only under acid or base catalysis but fully prevented at neutral conditions. For the first time, boronate ester cages 6 tolerate substantial amounts of water or alcohols both in solution and solid state. The unprecedented applicability of these materials under ambient and aqueous conditions is showcased by efficient encapsulation and on-demand release of ß-carotene dyes and heterogeneous water oxidation catalysis after the encapsulation of ruthenium catalysts.

6.
Hum Genet ; 143(8): 965-978, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39028335

RESUMEN

ARID1B is the most frequently mutated gene in Coffin-Siris syndrome (CSS). To date, the vast majority of causative variants reported in ARID1B are truncating, leading to nonsense-mediated mRNA decay. In the absence of experimental data, only few ARID1B amino acid substitutions have been classified as pathogenic, mainly based on clinical data and their de novo occurrence, while most others are currently interpreted as variants of unknown significance. The present study substantiates the pathogenesis of ARID1B non-truncating/NMD-escaping variants located in the SMARCA4-interacting EHD2 and DNA-binding ARID domains. Overexpression assays in cell lines revealed that the majority of EHD2 variants lead to protein misfolding and formation of cytoplasmic aggresomes surrounded by vimentin cage-like structures and co-localizing with the microtubule organisation center. ARID domain variants exhibited not only aggresomes, but also nuclear aggregates, demonstrating robust pathological effects. Protein levels were not compromised, as shown by quantitative western blot analysis. In silico structural analysis predicted the exposure of amylogenic segments in both domains due to the nearby variants, likely causing this aggregation. Genome-wide transcriptome and methylation analysis in affected individuals revealed expression and methylome patterns consistent with those of the pathogenic haploinsufficiency ARID1B alterations in CSS cases. These results further support pathogenicity and indicate two approaches for disambiguation of such variants in everyday practice. The few affected individuals harbouring EHD2 non-truncating variants described to date exhibit mild CSS clinical traits. In summary, this study paves the way for the re-evaluation of previously unclear ARID1B non-truncating variants and opens a new era in CSS genetic diagnosis.


Asunto(s)
Proteínas de Unión al ADN , Cara , Deformidades Congénitas de la Mano , Discapacidad Intelectual , Micrognatismo , Cuello , Factores de Transcripción , Humanos , Discapacidad Intelectual/genética , Micrognatismo/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Deformidades Congénitas de la Mano/genética , Cuello/anomalías , Cara/anomalías , Anomalías Múltiples/genética , Mutación , Masculino , Agregado de Proteínas
7.
Development ; 148(14)2021 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-34184026

RESUMEN

Transcription factor 4 (TCF4) is a crucial regulator of neurodevelopment and has been linked to the pathogenesis of autism, intellectual disability and schizophrenia. As a class I bHLH transcription factor (TF), it is assumed that TCF4 exerts its neurodevelopmental functions through dimerization with proneural class II bHLH TFs. Here, we aim to identify TF partners of TCF4 in the control of interhemispheric connectivity formation. Using a new bioinformatic strategy integrating TF expression levels and regulon activities from single cell RNA-sequencing data, we find evidence that TCF4 interacts with non-bHLH TFs and modulates their transcriptional activity in Satb2+ intercortical projection neurons. Notably, this network comprises regulators linked to the pathogenesis of neurodevelopmental disorders, e.g. FOXG1, SOX11 and BRG1. In support of the functional interaction of TCF4 with non-bHLH TFs, we find that TCF4 and SOX11 biochemically interact and cooperatively control commissure formation in vivo, and regulate the transcription of genes implicated in this process. In addition to identifying new candidate interactors of TCF4 in neurodevelopment, this study illustrates how scRNA-Seq data can be leveraged to predict TF networks in neurodevelopmental processes.


Asunto(s)
ARN Citoplasmático Pequeño/metabolismo , Análisis de la Célula Individual , Factor de Transcripción 4/genética , Factor de Transcripción 4/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Diferenciación Celular , ADN Helicasas , Embrión de Mamíferos , Factores de Transcripción Forkhead , Regulación del Desarrollo de la Expresión Génica , Redes Reguladoras de Genes , Discapacidad Intelectual , Proteínas de Unión a la Región de Fijación a la Matriz , Ratones , Ratones Noqueados , Proteínas del Tejido Nervioso , Neuronas/fisiología , Proteínas Nucleares , Dominios y Motivos de Interacción de Proteínas , ARN Citoplasmático Pequeño/genética , Factores de Transcripción SOXC , Esquizofrenia/genética , Esquizofrenia/metabolismo
8.
Cereb Cortex ; 33(3): 844-864, 2023 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-35296883

RESUMEN

Alcohol use, abuse, and addiction, and resulting health hazards are highly sex-dependent with unknown mechanisms. Previously, strong links between the SMPD3 gene and its coded protein neutral sphingomyelinase 2 (NSM) and alcohol abuse, emotional behavior, and bone defects were discovered and multiple mechanisms were identified for females. Here we report strong sex-dimorphisms for central, but not for peripheral mechanisms of NSM action in mouse models. Reduced NSM activity resulted in enhanced alcohol consumption in males, but delayed conditioned rewarding effects. It enhanced the acute dopamine response to alcohol, but decreased monoaminergic systems adaptations to chronic alcohol. Reduced NSM activity increased depression- and anxiety-like behavior, but was not involved in alcohol use for the self-management of the emotional state. Constitutively reduced NSM activity impaired structural development in the brain and enhanced lipidomic sensitivity to chronic alcohol. While the central effects were mostly opposite to NSM function in females, similar roles in bone-mediated osteocalcin release and its effects on alcohol drinking and emotional behavior were observed. These findings support the view that the NSM and multiple downstream mechanism may be a source of the sex-differences in alcohol use and emotional behavior.


Asunto(s)
Emociones , Esfingomielina Fosfodiesterasa , Masculino , Ratones , Animales , Femenino , Esfingomielina Fosfodiesterasa/genética , Esfingomielina Fosfodiesterasa/metabolismo , Consumo de Bebidas Alcohólicas , Ansiedad/metabolismo , Encéfalo/metabolismo , Etanol
9.
Am J Hum Genet ; 107(3): 544-554, 2020 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-32730804

RESUMEN

RNA polymerase II interacts with various other complexes and factors to ensure correct initiation, elongation, and termination of mRNA transcription. One of these proteins is SR-related CTD-associated factor 4 (SCAF4), which is important for correct usage of polyA sites for mRNA termination. Using exome sequencing and international matchmaking, we identified nine likely pathogenic germline variants in SCAF4 including two splice-site and seven truncating variants, all residing in the N-terminal two thirds of the protein. Eight of these variants occurred de novo, and one was inherited. Affected individuals demonstrated a variable neurodevelopmental disorder characterized by mild intellectual disability, seizures, behavioral abnormalities, and various skeletal and structural anomalies. Paired-end RNA sequencing on blood lymphocytes of SCAF4-deficient individuals revealed a broad deregulation of more than 9,000 genes and significant differential splicing of more than 2,900 genes, indicating an important role of SCAF4 in mRNA processing. Knockdown of the SCAF4 ortholog CG4266 in the model organism Drosophila melanogaster resulted in impaired locomotor function, learning, and short-term memory. Furthermore, we observed an increased number of active zones in larval neuromuscular junctions, representing large glutamatergic synapses. These observations indicate a role of CG4266 in nervous system development and function and support the implication of SCAF4 in neurodevelopmental phenotypes. In summary, our data show that heterozygous, likely gene-disrupting variants in SCAF4 are causative for a variable neurodevelopmental disorder associated with impaired mRNA processing.


Asunto(s)
Discapacidad Intelectual/genética , Trastornos del Neurodesarrollo/genética , Convulsiones/genética , Factores de Empalme Serina-Arginina/genética , Animales , Niño , Drosophila melanogaster/genética , Femenino , Técnicas de Silenciamiento del Gen , Variación Genética/genética , Heterocigoto , Humanos , Discapacidad Intelectual/fisiopatología , Locomoción/genética , Masculino , Mutación/genética , Trastornos del Neurodesarrollo/fisiopatología , ARN Polimerasa II/genética , Procesamiento Postranscripcional del ARN/genética , ARN Mensajero/genética , Convulsiones/fisiopatología , Secuenciación del Exoma
10.
Glia ; 70(3): 522-535, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34787332

RESUMEN

Recently, oligodendrocytes (Ol) have been attributed potential immunomodulatory effects. Yet, the exact mode of interaction with pathogenic CNS infiltrating lymphocytes remains unclear. Here, we attempt to dissect mechanisms of Ol modulation during neuroinflammation and characterize the interaction of Ol with pathogenic T cells. RNA expression analysis revealed an upregulation of immune-modulatory genes and adhesion molecules (AMs), ICAM-1 and VCAM-1, in Ol when isolated from mice undergoing experimental autoimmune encephalomyelitis (EAE). To explore whether AMs are involved in the interaction of Ol with infiltrating T cells, we performed co-culture studies on mature Ol and Th1 cells. Live cell imaging analysis showed direct interaction between both cell types. Eighty percentage of Th1 cells created contacts with Ol that lasted longer than 15 min, which may be regarded as physiologically relevant. Exposure of Ol to Th1 cells or their supernatant resulted in a significant extension of Ol processes, and upregulation of AMs as well as other immunomodulatory genes. Our observations indicate that blocking of oligodendroglial ICAM-1 can reduce the number of Th1 cells initially contacting the Ol. These results suggest that AMs may play a role in the interaction between Ol and Th1 cells. We identified Ol interacting with CD4+ cells in vivo in spinal cord tissue of EAE diseased mice indicating that our in vitro findings are of interest to further scientific research in this field. Further characterization and understanding of Ol interaction with infiltrating cells may lead to new therapeutic strategies enhancing Ol protection and remyelination potential. Oligodendrocytes regulate immune modulatory genes and adhesion molecules during autoimmune neuroinflammation Oligodendrocytes interact with Th1 cells in vitro in a physiologically relevant manner Adhesion molecules may be involved in Ol-Th1 cell interaction.


Asunto(s)
Encefalomielitis Autoinmune Experimental , Molécula 1 de Adhesión Intercelular/metabolismo , Animales , Encefalomielitis Autoinmune Experimental/patología , Molécula 1 de Adhesión Intercelular/genética , Ratones , Ratones Endogámicos C57BL , Enfermedades Neuroinflamatorias , Oligodendroglía/metabolismo
11.
Stem Cells ; 39(2): 227-239, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33270951

RESUMEN

Although the bone marrow contains most hematopoietic activity during adulthood, hematopoietic stem and progenitor cells can be recovered from various extramedullary sites. Cells with hematopoietic progenitor properties have even been reported in the adult brain under steady-state conditions, but their nature and localization remain insufficiently defined. Here, we describe a heterogeneous population of myeloid progenitors in the leptomeninges of adult C57BL/6 mice. This cell pool included common myeloid, granulocyte/macrophage, and megakaryocyte/erythrocyte progenitors. Accordingly, it gave rise to all major myelo-erythroid lineages in clonogenic culture assays. Brain-associated progenitors persisted after tissue perfusion and were partially inaccessible to intravenous antibodies, suggesting their localization behind continuous blood vessel endothelium such as the blood-arachnoid barrier. Flt3Cre lineage tracing and bone marrow transplantation showed that the precursors were derived from adult hematopoietic stem cells and were most likely continuously replaced via cell trafficking. Importantly, their occurrence was tied to the immunologic state of the central nervous system (CNS) and was diminished in the context of neuroinflammation and ischemic stroke. Our findings confirm the presence of myeloid progenitors at the meningeal border of the brain and lay the foundation to unravel their possible functions in CNS surveillance and local immune cell production.


Asunto(s)
Células de la Médula Ósea/fisiología , Trasplante de Médula Ósea/métodos , Encéfalo/fisiología , Diferenciación Celular/fisiología , Meninges/fisiología , Meninges/trasplante , Factores de Edad , Animales , Médula Ósea/fisiología , Encéfalo/citología , Femenino , Trasplante de Células Madre Hematopoyéticas/métodos , Células Madre Hematopoyéticas/fisiología , Masculino , Meninges/citología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos
12.
Mol Psychiatry ; 26(12): 7403-7416, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34584229

RESUMEN

Mental disorders are highly comorbid and occur together with physical diseases, which are often considered to arise from separate pathogenic pathways. We observed in alcohol-dependent patients increased serum activity of neutral sphingomyelinase. A genetic association analysis in 456,693 volunteers found associations of haplotypes of SMPD3 coding for NSM-2 (NSM) with alcohol consumption, but also with affective state, and bone mineralisation. Functional analysis in mice showed that NSM controls alcohol consumption, affective behaviour, and their interaction by regulating hippocampal volume, cortical connectivity, and monoaminergic responses. Furthermore, NSM controlled bone-brain communication by enhancing osteocalcin signalling, which can independently supress alcohol consumption and reduce depressive behaviour. Altogether, we identified a single gene source for multiple pathways originating in the brain and bone, which interlink disorders of a mental-physical co-morbidity trias of alcohol abuse-depression/anxiety-bone disorder. Targeting NSM and osteocalcin signalling may, thus, provide a new systems approach in the treatment of a mental-physical co-morbidity trias.


Asunto(s)
Alcoholismo , Enfermedades Óseas , Trastorno Depresivo Mayor , Esfingomielina Fosfodiesterasa , Alcoholismo/genética , Animales , Enfermedades Óseas/genética , Comorbilidad , Trastorno Depresivo Mayor/genética , Humanos , Ratones , Morbilidad , Esfingomielina Fosfodiesterasa/genética
13.
PLoS Biol ; 17(5): e3000301, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31150375

RESUMEN

Chaperone-mediated autophagy (CMA) contributes to the lysosomal degradation of a selective subset of proteins. Selectivity lies in the chaperone heat shock cognate 71 kDa protein (HSC70) recognizing a pentapeptide motif (KFERQ-like motif) in the protein sequence essential for subsequent targeting and degradation of CMA substrates in lysosomes. Interest in CMA is growing due to its recently identified regulatory roles in metabolism, differentiation, cell cycle, and its malfunctioning in aging and conditions such as cancer, neurodegeneration, or diabetes. Identification of the subset of the proteome amenable to CMA degradation could further expand our understanding of the pathophysiological relevance of this form of autophagy. To that effect, we have performed an in silico screen for KFERQ-like motifs across proteomes of several species. We have found that KFERQ-like motifs are more frequently located in solvent-exposed regions of proteins, and that the position of acidic and hydrophobic residues in the motif plays the most important role in motif construction. Cross-species comparison of proteomes revealed higher motif conservation in CMA-proficient species. The tools developed in this work have also allowed us to analyze the enrichment of motif-containing proteins in biological processes on an unprecedented scale and discover a previously unknown association between the type and combination of KFERQ-like motifs in proteins and their participation in specific biological processes. To facilitate further analysis by the scientific community, we have developed a free web-based resource (KFERQ finder) for direct identification of KFERQ-like motifs in any protein sequence. This resource will contribute to accelerating understanding of the physiological relevance of CMA.


Asunto(s)
Secuencias de Aminoácidos , Autofagia Mediada por Chaperones , Proteoma/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia Conservada , Drosophila melanogaster/genética , Evolución Molecular , Humanos , Ratones , Células 3T3 NIH , Proteoma/química , Saccharomyces cerevisiae/genética
14.
Int J Mol Sci ; 23(22)2022 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-36430692

RESUMEN

Multiple sclerosis (MS) is an autoimmune disease of the central nervous system (CNS). Although immune modulation and suppression are effective during relapsing-remitting MS, secondary progressive MS (SPMS) requires neuroregenerative therapeutic options that act on the CNS. The sphingosine-1-phosphate receptor modulator siponimod is the only approved drug for SPMS. In the pivotal trial, siponimod reduced disease progression and brain atrophy compared with placebo. The enteric nervous system (ENS) was recently identified as an additional autoimmune target in MS. We investigated the effects of siponimod on the ENS and CNS in the experimental autoimmune encephalomyelitis model of MS. Mice with late-stage disease were treated with siponimod, fingolimod, or sham. The clinical disease was monitored daily, and treatment success was verified using mass spectrometry and flow cytometry, which revealed peripheral lymphopenia in siponimod- and fingolimod-treated mice. We evaluated the mRNA expression, ultrastructure, and histopathology of the ENS and CNS. Single-cell RNA sequencing revealed an upregulation of proinflammatory genes in spinal cord astrocytes and ependymal cells in siponimod-treated mice. However, differences in CNS and ENS histopathology and ultrastructural pathology between the treatment groups were absent. Thus, our data suggest that siponimod and fingolimod act on the peripheral immune system and do not have pronounced direct neuroprotective effects.


Asunto(s)
Encefalomielitis Autoinmune Experimental , Esclerosis Múltiple , Ratones , Animales , Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Clorhidrato de Fingolimod/farmacología , Clorhidrato de Fingolimod/uso terapéutico , Compuestos de Bencilo/farmacología , Sistema Nervioso Central/patología , Esclerosis Múltiple/tratamiento farmacológico , Esclerosis Múltiple/patología
15.
Physiol Genomics ; 53(12): 509-517, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34704838

RESUMEN

Preterm neonates are at a high risk for nephron loss under adverse clinical conditions. Renal damage potentially collides with postnatal nephrogenesis. Recent animal studies suggest that nephron loss within this vulnerable phase leads to renal damage later in life. Nephrogenic pathways are commonly reactivated after kidney injury supporting renal regeneration. We hypothesized that nephron loss during nephrogenesis affects renal development, which, in turn, impairs tissue repair after secondary injury. Neonates prior to 36 wk of gestation show an active nephrogenesis. In rats, nephrogenesis is ongoing until day 10 after birth. Mimicking the situation of severe nephron loss during nephrogenesis, male pups were uninephrectomized at day 1 of life (UNXd1). A second group of males was uninephrectomized at postnatal day 14 (UNXd14), after terminated nephrogenesis. Age-matched controls were sham operated. Three days after uninephrectomy transcriptional changes in the right kidney were analyzed by RNA-sequencing, followed by functional pathway analysis. In UNXd1, 1,182 genes were differentially regulated, but only 143 genes showed a regulation both in UNXd1 and UNXd14. The functional groups "renal development" and "kidney injury" were among the most differentially regulated groups and revealed distinctive alterations. Reduced expression of candidate genes concerning renal development (Bmp7, Gdnf, Pdgf-B, Wt1) and injury (nephrin, podocin, Tgf-ß1) were detected. The downregulation of Bmp7 and Gdnf persisted until day 28. In UNXd14, Six2 was upregulated and Pax2 was downregulated. We conclude that nephron loss during nephrogenesis affects renal development and induces a specific regulation of genes that might hinder tissue repair after secondary kidney injury.


Asunto(s)
Lesión Renal Aguda/genética , Regulación hacia Abajo/genética , Regulación del Desarrollo de la Expresión Génica , Genes del Desarrollo , Nefronas/crecimiento & desarrollo , Nefronas/patología , Organogénesis/genética , Regulación hacia Arriba/genética , Animales , Animales Recién Nacidos/cirugía , Proteína Morfogenética Ósea 7/genética , Estudios de Casos y Controles , Modelos Animales de Enfermedad , Factor Neurotrófico Derivado de la Línea Celular Glial/genética , Proteínas de Homeodominio/genética , Masculino , Nefrectomía/métodos , Factor de Transcripción PAX2/genética , RNA-Seq/métodos , Ratas , Ratas Wistar , Transcriptoma/genética
16.
EMBO J ; 36(2): 135-150, 2017 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-27753622

RESUMEN

Rupture of endosomes and lysosomes is a major cellular stress condition leading to cell death and degeneration. Here, we identified an essential role for the ubiquitin-directed AAA-ATPase, p97, in the clearance of damaged lysosomes by autophagy. Upon damage, p97 translocates to lysosomes and there cooperates with a distinct set of cofactors including UBXD1, PLAA, and the deubiquitinating enzyme YOD1, which we term ELDR components for Endo-Lysosomal Damage Response. Together, they act downstream of K63-linked ubiquitination and p62 recruitment, and selectively remove K48-linked ubiquitin conjugates from a subpopulation of damaged lysosomes to promote autophagosome formation. Lysosomal clearance is also compromised in MEFs harboring a p97 mutation that causes inclusion body myopathy and neurodegeneration, and damaged lysosomes accumulate in affected patient tissue carrying the mutation. Moreover, we show that p97 helps clear late endosomes/lysosomes ruptured by endocytosed tau fibrils. Thus, our data reveal an important mechanism of how p97 maintains lysosomal homeostasis, and implicate the pathway as a modulator of degenerative diseases.


Asunto(s)
Adenosina Trifosfatasas/metabolismo , Autofagia , Proteínas Portadoras/metabolismo , Proteínas de Ciclo Celular/metabolismo , Endopeptidasas/metabolismo , Lisosomas/metabolismo , Proteínas/metabolismo , Tioléster Hidrolasas/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Proteínas Adaptadoras del Transporte Vesicular , Animales , Proteínas Relacionadas con la Autofagia , Células Cultivadas , Humanos , Ratones , Proteína que Contiene Valosina
17.
Ann Rheum Dis ; 80(4): 451-468, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33148700

RESUMEN

OBJECTIVES: Eosinophils possess pro-inflammatory functions in asthma. However, our recent studies have suggested that innate lymphoid cells type 2 (ILC2s) and eosinophils have proresolving properties in rheumatoid arthritis (RA). Nothing is known yet about the mechanisms determining the double-edged role of eosinophils. Therefore, we investigated whether asthma, a paradigm eosinophilic disease, can elicit resolution of chronic arthritis. METHODS: Ovalbumin-triggered eosinophilic asthma was combined with K/BxN serum-induced arthritis, where lung and synovial eosinophil subsets were compared by single-cell RNA sequencing (scRNA-seq). To investigate the involvement of the ILC2-interleukin-5 (IL-5) axis, hydrodynamic injection (HDI) of IL-25 and IL-33 plasmids, IL-5 reporter mice and anti-IL-5 antibody treatment were used. In patients with RA, the presence of distinct eosinophil subsets was examined in peripheral blood and synovial tissue. Disease activity of patients with RA with concomitant asthma was monitored before and after mepolizumab (anti-IL-5 antibody) therapy. RESULTS: The induction of eosinophilic asthma caused resolution of murine arthritis and joint tissue protection. ScRNA-seq revealed a specific subset of regulatory eosinophils (rEos) in the joints, distinct from inflammatory eosinophils in the lungs. Mechanistically, synovial rEos expanded on systemic upregulation of IL-5 released by lung ILC2s. Eosinophil depletion abolished the beneficial effect of asthma on arthritis. rEos were consistently present in the synovium of patients with RA in remission, but not in active stage. Remarkably, in patients with RA with concomitant asthma, mepolizumab treatment induced relapse of arthritis. CONCLUSION: These findings point to a hitherto undiscovered proresolving signature in an eosinophil subset that stimulates arthritis resolution.


Asunto(s)
Artritis Experimental , Artritis Reumatoide , Asma , Animales , Artritis Experimental/tratamiento farmacológico , Artritis Reumatoide/tratamiento farmacológico , Asma/tratamiento farmacológico , Eosinófilos , Humanos , Inmunidad Innata , Interleucina-5/farmacología , Linfocitos , Ratones
18.
J Biol Chem ; 288(10): 7363-72, 2013 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-23335559

RESUMEN

Caveolin-1 (CAV1) is the defining constituent of caveolae at the plasma membrane of many mammalian cells. For turnover, CAV1 is ubiquitinated and sorted to late endosomes and lysosomes. Sorting of CAV1 requires the AAA+-type ATPase VCP and its cofactor UBXD1. However, it is unclear in which region CAV1 is ubiquitinated and how ubiquitination is linked to sorting of CAV1 by VCP-UBXD1. Here, we show through site-directed mutagenesis that ubiquitination of CAV1 occurs at any of the six lysine residues, 5, 26, 30, 39, 47, and 57, that are clustered in the N-terminal region but not at lysines in the oligomerization, intramembrane, or C-terminal domains. Mutation of Lys-5-57 to arginines prevented binding of the VCP-UBXD1 complex and, importantly, strongly reduced recruitment of VCP-UBXD1 to endocytic compartments. Moreover, the Lys-5-57Arg mutation specifically interfered with trafficking of CAV1 from early to late endosomes. Conversely and consistently, depletion of VCP or UBXD1 led to accumulation of ubiquitinated CAV1, suggesting that VCP acts downstream of ubiquitination and is required for transport of the ubiquitinated form of CAV1 to late endosomes. These results define the N-terminal region of CAV1 as the critical ubiquitin conjugation site and, together with previous data, demonstrate the significance of this ubiquitination for binding to the VCP-UBXD1 complex and for sorting into lysosomes.


Asunto(s)
Adenosina Trifosfatasas/metabolismo , Proteínas Portadoras/metabolismo , Caveolina 1/metabolismo , Proteínas de Ciclo Celular/metabolismo , Endosomas/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Proteínas Adaptadoras del Transporte Vesicular , Adenosina Trifosfatasas/genética , Sustitución de Aminoácidos , Arginina/genética , Arginina/metabolismo , Proteínas Relacionadas con la Autofagia , Western Blotting , Proteínas Portadoras/genética , Caveolina 1/química , Caveolina 1/genética , Proteínas de Ciclo Celular/genética , Línea Celular Tumoral , Complejos de Clasificación Endosomal Requeridos para el Transporte/metabolismo , Células HEK293 , Humanos , Lisina/genética , Lisina/metabolismo , Lisosomas/metabolismo , Microscopía Confocal , Mutación , Transporte de Proteínas , Interferencia de ARN , Proteínas Ubiquitinadas/metabolismo , Ubiquitinación , Proteína que Contiene Valosina
19.
Endocr Pathol ; 35(2): 147-153, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38403790

RESUMEN

Traditionally considered non-functional low proliferative benign neuroendocrine proliferations measuring less than 5 mm, pancreatic (neuro)endocrine microadenomas are now classified as pancreatic neuroendocrine microtumors in the 2022 WHO classification of endocrine and neuroendocrine tumors. This case report discussed the features of an incidentally identified 4.7-mm glucagon-expressing pancreatic neuroendocrine microtumor with MEN1 mutation only, chromosomally stable and an epigenetic alpha-like phenotype. The tumor was associated with an unexplained increased proliferation rate in Ki-67 of 15%. There was no associated DAXX/ATRX deficiency. The presented case challenges the conventional thought of a low proliferative disease of the so-called "pancreatic neuroendocrine microadenomas" and provides additional support to the 2022 WHO classification that also requires grading of these neoplasms. Despite exhibiting molecular features of less aggressive behavior, the case also underscores the biological complexity of pancreatic neuroendocrine microtumors. By recognizing the heterogenous spectrum of neuroendocrine neoplasms, the current case also contributes to ongoing discussions on how to optimize the clinical management of such tumors.


Asunto(s)
Tumores Neuroendocrinos , Neoplasias Pancreáticas , Humanos , Persona de Mediana Edad , Proliferación Celular , Clasificación del Tumor , Tumores Neuroendocrinos/patología , Tumores Neuroendocrinos/genética , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/genética , Proteínas Proto-Oncogénicas/genética
20.
NPJ Precis Oncol ; 8(1): 59, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38429350

RESUMEN

There are no therapeutic predictive biomarkers or representative preclinical models for high-grade gastroenteropancreatic neuroendocrine neoplasms (GEP-NEN), a highly aggressive, fatal, and heterogeneous malignancy. We established patient-derived (PD) tumoroids from biobanked tissue samples of advanced high-grade GEP-NEN patients and applied this model for targeted rapid ex vivo pharmacotyping, next-generation sequencing, and perturbational profiling. We used tissue-matched PD tumoroids to profile individual patients, compared ex vivo drug response to patients' clinical response to chemotherapy, and investigated treatment-induced adaptive stress responses.PD tumoroids recapitulated biological key features of high-grade GEP-NEN and mimicked clinical response to cisplatin and temozolomide ex vivo. When we investigated treatment-induced adaptive stress responses in PD tumoroids in silico, we discovered and functionally validated Lysine demethylase 5 A and interferon-beta, which act synergistically in combination with cisplatin. Since ex vivo drug response in PD tumoroids matched clinical patient responses to standard-of-care chemotherapeutics for GEP-NEN, our rapid and functional precision oncology approach could expand personalized therapeutic options for patients with advanced high-grade GEP-NEN.

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