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1.
Nat Commun ; 11(1): 4549, 2020 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-32917889

RESUMO

Arterial macrophages have different developmental origins, but the association of macrophage ontogeny with their phenotypes and functions in adulthood is still unclear. Here, we combine macrophage fate-mapping analysis with single-cell RNA sequencing to establish their cellular identity during homeostasis, and in response to angiotensin-II (AngII)-induced arterial inflammation. Yolk sac erythro-myeloid progenitors (EMP) contribute substantially to adventitial macrophages and give rise to a defined cluster of resident immune cells with homeostatic functions that is stable in adult mice, but declines in numbers during ageing and is not replenished by bone marrow (BM)-derived macrophages. In response to AngII inflammation, increase in adventitial macrophages is driven by recruitment of BM monocytes, while EMP-derived macrophages proliferate locally and provide a distinct transcriptional response that is linked to tissue regeneration. Our findings thus contribute to the understanding of macrophage heterogeneity, and associate macrophage ontogeny with distinct functions in health and disease.


Assuntos
Artérias/citologia , Arterite/imunologia , Diferenciação Celular/fisiologia , Homeostase/fisiologia , Macrófagos/fisiologia , Envelhecimento/fisiologia , Angiotensina II/administração & dosagem , Angiotensina II/imunologia , Animais , Artérias/fisiologia , Medula Óssea/fisiologia , Transplante de Medula Óssea , Linhagem da Célula , Modelos Animais de Doenças , Feminino , Células-Tronco Hematopoéticas/fisiologia , Humanos , Masculino , Camundongos , Camundongos Transgênicos , RNA-Seq , Regeneração/fisiologia , Análise de Célula Única , Quimeras de Transplante
2.
Phys Rev Lett ; 125(8): 088101, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32909810

RESUMO

Characterization of the differences between biological and random networks can reveal the design principles that enable the robust realization of crucial biological functions including the establishment of different cell types. Previous studies, focusing on identifying topological features that are present in biological networks but not in random networks, have, however, provided few functional insights. We use a Boolean modeling framework and ideas from the spin glass literature to identify functional differences between five real biological networks and random networks with similar topological features. We show that minimal frustration is a fundamental property that allows biological networks to robustly establish cell types and regulate cell fate choice, and that this property can emerge in complex networks via Darwinian evolution. The study also provides clues regarding how the regulation of cell fate choice can go awry in a disease like cancer and lead to the emergence of aberrant cell types.


Assuntos
Fenômenos Fisiológicos Celulares , Modelos Biológicos , Diferenciação Celular/fisiologia , Células-Tronco Embrionárias/fisiologia , Humanos
3.
PLoS One ; 15(8): e0238132, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32853221

RESUMO

Bears do not suffer from osteoporosis during hibernation, which is associated with long-term inactivity, lack of food intake, and cold exposure. However, the mechanisms involved in bone loss prevention have scarcely been elucidated in bears. We investigated the effect of serum from hibernating Japanese black bears (Ursus thibetanus japonicus) on differentiation of peripheral blood mononuclear cells (PBMCs) to osteoclasts (OCs). PBMCs collected from 3 bears were separately cultured with 10% serum of 4 active and 4 hibernating bears (each individual serum type was assessed separately by a bear PBMCs), and differentiation were induced by treatment with macrophage colony stimulating factor (M-CSF) and receptor activator of NF-kB ligand (RANKL). PBMCs that were cultured with the active bear serum containing medium (ABSM) differentiated to multi-nucleated OCs, and were positive for TRAP stain. However, cells supplemented with hibernating bear serum containing medium (HBSM) failed to form OCs, and showed significantly lower TRAP stain (p < 0.001). On the other hand, HBSM induced proliferation of adipose derived mesenchymal stem cells (ADSCs) similarly to ABSM (p > 0.05), indicating no difference on cell growth. It was revealed that osteoclastogenesis of PBMCs is hindered by HBSM, implying an underlying mechanism for the suppressed bone resorption during hibernation in bears. In addition, this study for the first time showed the formation of bears' OCs in-vitro.


Assuntos
Hibernação/fisiologia , Osteoclastos/fisiologia , Osteogênese/fisiologia , Ursidae/fisiologia , Animais , Reabsorção Óssea/metabolismo , Reabsorção Óssea/fisiopatologia , Diferenciação Celular/fisiologia , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/fisiologia , Fator Estimulador de Colônias de Macrófagos/metabolismo , Masculino , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/fisiologia , Osteoclastos/metabolismo , Osteoporose/metabolismo , Osteoporose/fisiopatologia , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Ursidae/metabolismo
4.
Nat Commun ; 11(1): 3989, 2020 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-32778653

RESUMO

Upon stimulation, B cells assume heterogeneous cell fates, with only a fraction differentiating into antibody-secreting cells (ASC). Here we investigate B cell fate programming and heterogeneity during ASC differentiation using T cell-independent models. We find that maximal ASC induction requires at least eight cell divisions in vivo, with BLIMP-1 being required for differentiation at division eight. Single cell RNA-sequencing of activated B cells and construction of differentiation trajectories reveal an early cell fate bifurcation. The ASC-destined branch requires induction of IRF4, MYC-target genes, and oxidative phosphorylation, with the loss of CD62L expression serving as a potential early marker of ASC fate commitment. Meanwhile, the non-ASC branch expresses an inflammatory signature, and maintains B cell fate programming. Finally, ASC can be further subseted based on their differential responses to ER-stress, indicating multiple development branch points. Our data thus define the cell division kinetics of B cell differentiation in vivo, and identify the molecular trajectories of B cell fate and ASC formation.


Assuntos
Células Produtoras de Anticorpos/metabolismo , Linfócitos B/imunologia , Ativação Linfocitária/fisiologia , Animais , Antígenos CD19/genética , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Imunidade , Fatores Reguladores de Interferon/metabolismo , Selectina L , Ativação Linfocitária/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 1 de Ligação ao Domínio I Regulador Positivo/genética , Fator 1 de Ligação ao Domínio I Regulador Positivo/metabolismo , Transcriptoma
5.
Life Sci ; 258: 118227, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32781074

RESUMO

AIM: eEF1A2 is highly expressed in postmitotic cells and has been reported to interact with the antioxidant enzyme peroxiredoxin 1 (PRDX1). PRDX1 is involved in motor neuron differentiation. Here, we studied the relationship between eEF1A2 and PRDX1 during dopaminergic neuron differentiation, and examined their possible association in an oxidative stress model of Parkinson's disease (PD). MAIN METHODS: Expression of eEF1A2 and PRDX1 in SH-SY5Y cells at various durations of retinoic acid (RA) induction was detected using qRT-PCR, Western blotting and immunofluorescence. Neurons of 10-day differentiation were treated with the PRDX1 inhibitor H7, MPP+ and H7 plus MPP+. The cell viability, the amounts of apoptotic nuclei, DHE signals, and the expression of p53, p-Akt and p-mTOR were determined. The colocalization of eEF1A2 and PRDX1 was visualized using confocal microscopy. KEY FINDINGS: eEF1A2 gradually increased after RA-induced differentiation of SH-SY5Y cells, while PRDX1 protein gradually decreased. MPP+ treatment increased eEF1A2 in both undifferentiated and differentiated neurons; however, PRDX1 appeared to elevate only in mature neurons. The inhibition of the PRDX1 activity with H7 promoted MPP+-induced cell death, as evidenced by decreased cell viability, increased apoptotic nuclei, increased the DHE signal, and increased p53. However, H7 induced the activation of the prosurvival Akt and mTOR in MPP+-treated cells. Besides, a colocalization of eEF1A2 and PRDX1 was evidenced in MPP+-treated neurons. This colocalization was possibly prevented by inhibiting the PRDX1 activity, resulting in aggravated neuronal death. SIGNIFICANCE: Our results suggest that the possible association between eEF1A2 and PRDX1 may be a promising target for modifying neuronal death in PD.


Assuntos
1-Metil-4-fenilpiridínio/toxicidade , Diferenciação Celular/fisiologia , Fator 1 de Elongação de Peptídeos/metabolismo , Peroxirredoxinas/antagonistas & inibidores , Peroxirredoxinas/metabolismo , Antioxidantes/metabolismo , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Herbicidas/toxicidade , Humanos , Fator 1 de Elongação de Peptídeos/análise , Peroxirredoxinas/análise
6.
Small ; 16(38): e2003010, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32815251

RESUMO

Currently, mesenchymal stem cells (MSCs)-based therapies for bone regeneration and treatments have gained significant attention in clinical research. Though many chemical and physical cues which influence the osteogenic differentiation of MSCs have been explored, scaffolds combining the benefits of Zn2+ ions and unique nanostructures may become an ideal interface to enhance osteogenic and anti-infective capabilities simultaneously. In this work, motivated by the enormous advantages of Zn-based metal-organic framework-derived nanocarbons, C-ZnO nanocarbons-modified fibrous scaffolds for stem cell-based osteogenic differentiation are constructed. The modified scaffolds show enhanced expression of alkaline phosphatase, bone sialoprotein, vinculin, and a larger cell spreading area. Meanwhile, the caging of ZnO nanoparticles can allow the slow release of Zn2+ ions, which not only activate various signaling pathways to guide osteogenic differentiation but also prevent the potential bacterial infection of implantable scaffolds. Overall, this study may provide new insight for designing stem cell-based nanostructured fibrous scaffolds with simultaneously enhanced osteogenic and anti-infective capabilities.


Assuntos
Carbono/química , Células-Tronco Mesenquimais/citologia , Nanofibras/química , Osteogênese/fisiologia , Tecidos Suporte/química , Óxido de Zinco/química , Fosfatase Alcalina/metabolismo , Diferenciação Celular/fisiologia , Células Cultivadas , Humanos , Sialoproteína de Ligação à Integrina/metabolismo , Teste de Materiais , Células-Tronco Mesenquimais/metabolismo , Microscopia Eletrônica de Varredura , Nanofibras/ultraestrutura , Transdução de Sinais , Engenharia Tecidual , Vinculina/metabolismo
7.
PLoS One ; 15(8): e0237182, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764797

RESUMO

Necrotizing enterocolitis is the most common gastrointestinal disorder in premature neonates. This disease is characterized by massive epithelial necrosis, gut barrier dysfunction and improper mucosal defense development. Studies have shown that probiotic administration can decrease NEC incidence and mortality. The proposed mechanisms of probiotics for the prevention of NEC are: promotion of intestinal development; improved barrier function through decreased apoptosis and improved mucin production; decreased expression of proinflammatory cytokines IL6, IL8, and TNFα, and modulation of microbiota dysbiosis in preterm infants. However, reported sepsis in the immunocompromised preterm host has deterred routine prophylactic administration of probiotics in the neonatal intensive care unit. We hypothesize that maternal administration of probiotics to pregnant mouse dams can recapitulate the beneficial effects observed in neonates fed with probiotics directly. We exposed pregnant mice to the probiotics and monitored the changes in the developing intestines of the offspring. Pregnant mice were fed daily with the probiotics Lactobacillus acidophilus and Bifidobacterium infantis (LB) from embryonic day15 to 2-week-old postnatally. Intraperitoneal administration of IL-1ß in the pups was used to model proinflammatory insults. Sera were collected at 2 weeks of age and evaluated for inflammatory cytokines by enzyme-linked-immunosorbent-assay and gut permeability by Fluorescein isothiocyanate-dextran tracer assay. Ileal tissues were collected for the evaluation of apoptosis and proliferation of the intestinal epithelium; as well as mucin and tight junction integrity at mucosal surface by immunofluorescent staining. We find that maternal LB exposure facilitated intestinal epithelial cell differentiation, prevented loss of mucin and preserved the intestinal integrity and barrier function and decreased serum levels of IL-1ß, TNF-α and IL-6 in the preweaned offsprings. in LB exposed pups. We demonstrate that maternal probiotic supplementation promotes gut maturation in developing offspring. This is potentially a safe alternative therapy to induce intestinal maturation and prevent prematurity-associated neonatal disorders.


Assuntos
Enterocolite Necrosante/prevenção & controle , Microbioma Gastrointestinal/fisiologia , Mucosa Intestinal/crescimento & desenvolvimento , Exposição Materna , Probióticos/administração & dosagem , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Animais Recém-Nascidos/microbiologia , Bifidobacterium longum subspecies infantis , Diferenciação Celular/fisiologia , Modelos Animais de Doenças , Enterocolite Necrosante/imunologia , Enterocolite Necrosante/microbiologia , Enterocolite Necrosante/patologia , Fezes/microbiologia , Feminino , Interações entre Hospedeiro e Microrganismos/fisiologia , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Interleucina-1beta/administração & dosagem , Interleucina-1beta/imunologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/microbiologia , Mucosa Intestinal/patologia , Lactobacillus acidophilus , Camundongos
8.
Nat Commun ; 11(1): 4071, 2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32792491

RESUMO

Arrest of oligodendrocyte (OL) differentiation and remyelination following myelin damage in multiple sclerosis (MS) is associated with neurodegeneration and clinical worsening. We show that Glutathione S-transferase 4α (Gsta4) is highly expressed during adult OL differentiation and that Gsta4 loss impairs differentiation into myelinating OLs in vitro. In addition, we identify Gsta4 as a target of both dimethyl fumarate, an existing MS therapy, and clemastine fumarate, a candidate remyelinating agent in MS. Overexpression of Gsta4 reduces expression of Fas and activity of the mitochondria-associated Casp8-Bid-axis in adult oligodendrocyte precursor cells, leading to improved OL survival during differentiation. The Gsta4 effect on apoptosis during adult OL differentiation was corroborated in vivo in both lysolecithin-induced demyelination and experimental autoimmune encephalomyelitis models, where Casp8 activity was reduced in Gsta4-overexpressing OLs. Our results identify Gsta4 as an intrinsic regulator of OL differentiation, survival and remyelination, as well as a potential target for future reparative MS therapies.


Assuntos
Glutationa Transferase/metabolismo , Oligodendroglia/citologia , Oligodendroglia/metabolismo , Animais , Apoptose/genética , Apoptose/fisiologia , Caspase 8/genética , Caspase 8/metabolismo , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Glutationa Transferase/genética , Homeostase/genética , Homeostase/fisiologia , Imuno-Histoquímica , Masculino , Microglia/citologia , Microglia/metabolismo , Microscopia Eletrônica de Transmissão , Mitocôndrias/metabolismo , Esclerose Múltipla/genética , Esclerose Múltipla/metabolismo , Fagocitose/genética , Fagocitose/fisiologia , Processamento de Proteína Pós-Traducional , Ratos , Reação em Cadeia da Polimerase em Tempo Real , Remielinização/genética , Remielinização/fisiologia
9.
Nat Commun ; 11(1): 4060, 2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32792512

RESUMO

Chromatin modifiers affect spatiotemporal gene expression programs that underlie organismal development. The Polycomb repressive complex 2 (PRC2) is a crucial chromatin modifier in executing neurodevelopmental programs. Here, we find that PRC2 interacts with the nucleic acid-binding protein Ybx1. In the mouse embryo in vivo, Ybx1 is required for forebrain specification and restricting mid-hindbrain growth. In neural progenitor cells (NPCs), Ybx1 controls self-renewal and neuronal differentiation. Mechanistically, Ybx1 highly overlaps PRC2 binding genome-wide, controls PRC2 distribution, and inhibits H3K27me3 levels. These functions are consistent with Ybx1-mediated promotion of genes involved in forebrain specification, cell proliferation, or neuronal differentiation. In Ybx1-knockout NPCs, H3K27me3 reduction by PRC2 enzymatic inhibitor or genetic depletion partially rescues gene expression and NPC functions. Our findings suggest that Ybx1 fine-tunes PRC2 activities to regulate spatiotemporal gene expression in embryonic neural development and uncover a crucial epigenetic mechanism balancing forebrain-hindbrain lineages and self-renewal-differentiation choices in NPCs.


Assuntos
Encéfalo/embriologia , Encéfalo/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Fatores de Transcrição/metabolismo , Animais , Western Blotting , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Proliferação de Células/genética , Proliferação de Células/fisiologia , Células Cultivadas , Imunoprecipitação da Cromatina , Drosophila , Epigênese Genética/genética , Citometria de Fluxo , Imunofluorescência , Histona-Lisina N-Metiltransferase/genética , Imunoprecipitação , Camundongos , Camundongos Knockout , Processamento de Proteína Pós-Traducional/genética , Processamento de Proteína Pós-Traducional/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição/genética
10.
PLoS Comput Biol ; 16(8): e1008076, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32745094

RESUMO

We consider how a signalling system can act as an information hub by multiplexing information arising from multiple signals. We formally define multiplexing, mathematically characterise which systems can multiplex and how well they can do it. While the results of this paper are theoretical, to motivate the idea of multiplexing, we provide experimental evidence that tentatively suggests that the NF-κB transcription factor can multiplex information about changes in multiple signals. We believe that our theoretical results may resolve the apparent paradox of how a system like NF-κB that regulates cell fate and inflammatory signalling in response to diverse stimuli can appear to have the low information carrying capacity suggested by recent studies on scalar signals. In carrying out our study, we introduce new methods for the analysis of large, nonlinear stochastic dynamic models, and develop computational algorithms that facilitate the calculation of fundamental constructs of information theory such as Kullback-Leibler divergences and sensitivity matrices, and link these methods to a new theory about multiplexing information. We show that many current models such as those of the NF-κB system cannot multiplex effectively and provide models that overcome this limitation using post-transcriptional modifications.


Assuntos
Comunicação Celular/fisiologia , Modelos Biológicos , Transdução de Sinais/fisiologia , Algoritmos , Diferenciação Celular/fisiologia , Linhagem Celular Tumoral , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Regulação da Expressão Gênica , Humanos , Teoria da Informação , NF-kappa B/metabolismo , Análise de Célula Única , Processos Estocásticos
11.
Nat Commun ; 11(1): 4278, 2020 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-32855388

RESUMO

Activation and migration of endogenous mesenchymal stromal cells (MSCs) are critical for bone regeneration. Here, we report a combinational peptide screening strategy for rapid discovery of ligands that not only bind strongly to osteogenic progenitor cells (OPCs) but also stimulate osteogenic cell Akt signaling in those OPCs. Two lead compounds are discovered, YLL3 and YLL8, both of which increase osteoprogenitor osteogenic differentiation in vitro. When given to normal or osteopenic mice, the compounds increase mineral apposition rate, bone formation, bone mass, and bone strength, as well as expedite fracture repair through stimulated endogenous osteogenesis. When covalently conjugated to alendronate, YLLs acquire an additional function resulting in a "tri-functional" compound that: (i) binds to OPCs, (ii) targets bone, and (iii) induces "pro-survival" signal. These bone-targeted, osteogenic peptides are well suited for current tissue-specific therapeutic paradigms to augment the endogenous osteogenic cells for bone regeneration and the treatment of bone loss.


Assuntos
Anabolizantes/farmacologia , Fraturas Ósseas/tratamento farmacológico , Osteogênese/efeitos dos fármacos , Peptídeos/farmacologia , Células-Tronco/efeitos dos fármacos , Anabolizantes/química , Animais , Calcificação Fisiológica/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Células Cultivadas , Feminino , Fraturas Ósseas/patologia , Humanos , Masculino , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Orquiectomia , Osteogênese/fisiologia , Ovariectomia , Peptídeos/química , Peptídeos/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Técnicas de Síntese em Fase Sólida , Células-Tronco/citologia
12.
Plant Mol Biol ; 104(3): 263-281, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32740898

RESUMO

KEY MESSAGE: Plant-specific Dof transcription factors VDOF1 and VDOF2 are novel regulators of vascular cell differentiation through the course of a lifetime in Arabidopsis, with shifting their transcriptional target genes. Vascular system is one of critical tissues for vascular plants to transport low-molecular compounds, such as water, minerals, and the photosynthetic product, sucrose. Here, we report the involvement of two Dof transcription factors, named VASCULAR-RELATED DOF1 (VDOF1)/VDOF4.6 and VDOF2/VDOF1.8, in vascular cell differentiation and lignin biosynthesis in Arabidopsis. VDOF genes were expressed in vascular tissues, but the detailed expression sites were partly different between VDOF1 and VDOF2. Vein patterning and lignin analysis of VDOF overexpressors and double mutant vdof1 vdof2 suggested that VDOF1 and VDOF2 would function as negative regulators of vein formation in seedlings, and lignin deposition in inflorescence stems. Interestingly, effects of VDOF overexpression in lignin deposition were different by developmental stages of inflorescence stems, and total lignin contents were increased and decreased in VDOF1 and VDOF2 overexpressors, respectively. RNA-seq analysis of inducible VDOF overexpressors demonstrated that the genes for cell wall biosynthesis, including lignin biosynthetic genes, and the transcription factor genes related to stress response and brassinosteroid signaling were commonly affected by VDOF1 and VDOF2 overexpression. Taken together, we concluded that VDOF1 and VDOF2 are novel regulators of vascular cell differentiation through the course of a lifetime, with shifting their transcriptional target genes: in seedlings, the VDOF genes negatively regulate vein formation, while at reproductive stages, the VDOF proteins target lignin biosynthesis.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Diferenciação Celular/fisiologia , Lignina/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Ligação a DNA , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Inflorescência , Mutação , Caules de Planta/citologia , Caules de Planta/metabolismo , Plantas Geneticamente Modificadas/genética , Sementes , Análise de Sequência
13.
Expert Opin Biol Ther ; 20(9): 1025-1031, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32700604

RESUMO

INTRODUCTION: The globally rampant SARS CoV-2 pandemic requires novel medical strategies to control the severity of disease and death due to complications. Of the 15-20% patients that develop pulmonary symptoms, a sub-set develops an acute respiratory distress syndrome (ARDS) rapidly progressing into a critical condition. Marked elevation of cytokines/chemokines is observed with elevation of additional markers of inflammation, coagulation, and organ damage such as CRP, D-dimer, LDH, Ferritin and Troponin-I. This hyperinflammation leads to worsening of oxygen saturation due to pulmonary infiltration and exudation, organ damage, and dysfunction of coagulation pathway and may lead to multi-organ failure. AREAS COVERED: The role of anti-inflammatory monoclonal antibodies such as Itolizumab, in cytokine storm. EXPERT OPINION: Itolizumab, an anti-CD6 humanized IgG1 mAb, binds to domain-1 of CD-6 that is responsible for priming, activation, and differentiation of T-cells. Itolizumab significantly reduces T-cell proliferation along with substantial downregulation of the production of cytokines/chemokines. Approved for moderate to severe chronic plaque psoriasis in 2013 it is currently being studied for addressing COVID-19 related cytokine storm and its complications. This article reviews its use in COVID-19 infections; its dose, administration protocol, contra-indications, and safety in treating moderate-to-severe ARDS by preventing and treating the cytokine storm and its complications.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos T/imunologia , Betacoronavirus , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/imunologia , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/imunologia , Anticorpos Monoclonais Humanizados/farmacologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Citocinas/antagonistas & inibidores , Citocinas/imunologia , Humanos , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/fisiologia , Pandemias , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Resultado do Tratamento
14.
Am J Physiol Gastrointest Liver Physiol ; 319(2): G189-G196, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32628072

RESUMO

To fulfill the lifelong need to supply diverse epithelial cells, intestinal stem cells (ISCs) rely on executing accurate transcriptional programs. This review addresses the mechanisms that control those programs. Genes that define cell behaviors and identities are regulated principally through thousands of dispersed enhancers, each individually <1 kb long and positioned from a few to hundreds of kilobases away from transcription start sites, upstream or downstream from coding genes or within introns. Wnt, Notch, and other epithelial control signals feed into these cis-regulatory DNA elements, which are also common loci of polymorphisms and mutations that confer disease risk. Cell-specific gene activity requires promoters to interact with the correct combination of signal-responsive enhancers. We review the current state of knowledge in ISCs regarding active enhancers, the nucleosome modifications that may enable appropriate and hinder inappropriate enhancer-promoter contacts, and the roles of lineage-restricted transcription factors.


Assuntos
Diferenciação Celular/fisiologia , Epigênese Genética , Intestinos/citologia , Células-Tronco/fisiologia , Animais , Regulação da Expressão Gênica , Humanos
15.
J Vis Exp ; (161)2020 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-32716390

RESUMO

The limited reserve of mature, fertilizable oocytes represents a major barrier for the success of assisted reproduction in mammals. Considering that during the reproductive life span only about 1% of the oocytes in an ovary mature and ovulate, several techniques have been developed to increase the exploitation of the ovarian reserve to the growing population of non-ovulatory follicles. Such technologies have allowed interventions of fertility preservation, selection programs in livestock, and conservation of endangered species. However, the vast potential of the ovarian reserve is still largely unexploited. In cows, for instance, some attempts have been made to support in vitro culture of oocytes at specific developmental stages, but efficient and reliable protocols have not yet been developed. Here we describe a culture system that reproduce the physiological conditions of the corresponding follicular stage, defined to develop in vitro growing oocytes collected from bovine early antral follicles to the fully-grown stage, corresponding to the medium antral follicle in vivo. A combination of hormones and a phosphodiesterase 3 inhibitor was used to prevent untimely meiotic resumption and to guide oocyte's differentiation.


Assuntos
Técnicas de Cultura de Células/métodos , Oócitos/fisiologia , Reserva Ovariana/fisiologia , Reprodução/fisiologia , Animais , Bovinos , Ciclo Celular/fisiologia , Diferenciação Celular/fisiologia , Feminino , Oogênese/fisiologia , Folículo Ovariano/fisiologia , Ovário/citologia , Ovário/fisiologia
16.
Prostate ; 80(12): 1012-1023, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32649013

RESUMO

BACKGROUND: Small cell neuroendocrine (NE) carcinomas of the prostate classically lose androgen receptor (AR) expression, may harbor loss of the RB1, TP53, and PTEN tumor suppressor genes, and are associated with a poor prognosis. However usual-type adenocarcinomas may also contain areas of NE differentiation, and in this context the molecular features and biological significance are less certain. METHODS: We examined the molecular phenotype and oncologic outcomes of primary prostate adenocarcinomas with ≥5% NE differentiation (≥5% chromogranin A-positive NE cells in any given tumor spot on tissue microarray) using three independent study sets: a set of tumors with paneth cell-like NE differentiation (n = 26), a retrospective case-cohort of intermediate- and high-risk patients enriched for adverse outcomes (n = 267), and primary tumors from a retrospective series of men with eventual castration-resistant metastatic prostate cancer (CRPC) treated with abiraterone or enzalutamide (n = 55). RESULTS: Benign NE cells expressed significantly lower quantified AR levels compared with paired benign luminal cells (P < .001). Similarly, paneth-like NE carcinoma cells or carcinoma cells expressing chromogranin A expressed significantly lower quantified AR levels than paired non-NE carcinoma cells (P < .001). Quantified ERG protein expression, was also lower in chromogranin A-labeled adenocarcinoma cells compared with unlabeled cells (P < .001) and tumors with NE differentiation showed lower gene expression scores for AR activity compared with those without. Despite evidence of lower AR signaling, adenocarcinomas with NE differentiation did not differ by prevalence of TP53 missense mutations, or PTEN or RB1 loss, compared with those without NE differentiation. Finally, NE differentiation was not associated with time to metastasis in intermediate- and high-risk patients (P = .6 on multivariate analysis), nor with progression-free survival in patients with CRPC treated with abiraterone or enzalutamide (P = .9). CONCLUSION: NE differentiation in usual-type primary prostate adenocarcinoma is a molecularly and clinically distinct form of lineage plasticity from that occurring in small cell NE carcinoma.


Assuntos
Células Neuroendócrinas/patologia , Tumores Neuroendócrinos/patologia , Neoplasias da Próstata/patologia , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Carcinoma de Células Pequenas/genética , Carcinoma de Células Pequenas/metabolismo , Carcinoma de Células Pequenas/patologia , Diferenciação Celular/fisiologia , Estudos de Coortes , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Células Neuroendócrinas/metabolismo , Tumores Neuroendócrinos/genética , Tumores Neuroendócrinos/metabolismo , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/patologia , Receptores Androgênicos/biossíntese , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Proteínas de Ligação a Retinoblastoma/genética , Proteínas de Ligação a Retinoblastoma/metabolismo , Estudos Retrospectivos , Transdução de Sinais , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
17.
Mol Cell Biol ; 40(17)2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-32601106

RESUMO

Transcription factors C/EBPß and C/EBPδ are induced within hours after initiation of adipogenesis in culture. They directly promote the expression of master adipogenic transcription factors peroxisome proliferator-activated receptor γ (PPARγ) and C/EBPα and are required for adipogenesis in vivo However, the mechanism that controls the induction of C/EBPß and C/EBPδ remains elusive. We previously showed that histone methyltransferases MLL3/MLL4 and associated PTIP are required for the induction of PPARγ and C/EBPα during adipogenesis. Here, we show MLL3/MLL4/PTIP-associated protein PAGR1 (also known as PA1) cooperates with phosphorylated CREB and ligand-activated glucocorticoid receptor to directly control the induction of C/EBPß and C/EBPδ in the early phase of adipogenesis. Deletion of Pagr1 in white and brown preadipocytes prevents the induction of C/EBPß and C/EBPδ and leads to severe defects in adipogenesis. Adipogenesis defects in PAGR1-deficient cells can be rescued by the ectopic expression of C/EBPß or PPARγ. Finally, the deletion of Pagr1 in Myf5+ precursor cells impairs brown adipose tissue and muscle development. Thus, by controlling the induction of C/EBPß and C/EBPδ, PAGR1 plays a critical role in adipogenesis.


Assuntos
Adipogenia/fisiologia , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Proteína delta de Ligação ao Facilitador CCAAT/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ligação a DNA/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Células 3T3-L1 , Adipócitos/metabolismo , Tecido Adiposo Marrom/metabolismo , Animais , Diferenciação Celular/fisiologia , Histona Metiltransferases/metabolismo , Camundongos , Camundongos Knockout , PPAR gama/metabolismo , Ligação Proteica
18.
Mol Cell Biol ; 40(18)2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32661120

RESUMO

The DNA and protein complex known as chromatin is subject to posttranslational modifications (PTMs) that regulate cellular functions such that PTM dysregulation can lead to disease, including cancer. One critical PTM is acetylation/deacetylation, which is being investigated as a means to develop targeted cancer therapies. The histone acetyltransferase (HAT) family of proteins performs histone acetylation. In humans, MOF (hMOF), a member of the MYST family of HATs, acetylates histone H4 at lysine 16 (H4K16ac). MOF-mediated acetylation plays a critical role in the DNA damage response (DDR) and embryonic stem cell development. Functionally, MOF is found in two distinct complexes: NSL (nonspecific lethal) in humans and MSL (male-specific lethal) in flies. The NSL complex is also able to acetylate additional histone H4 sites. Dysregulation of MOF activity occurs in multiple cancers, including ovarian cancer, medulloblastoma, breast cancer, colorectal cancer, and lung cancer. Bioinformatics analysis of KAT8, the gene encoding hMOF, indicated that it is highly overexpressed in kidney tumors as part of a concerted gene coexpression program that can support high levels of chromosome segregation and cell proliferation. The linkage between MOF and tumor proliferation suggests that there are additional functions of MOF that remain to be discovered.


Assuntos
Dano ao DNA , Células-Tronco Embrionárias/citologia , Histona Acetiltransferases/metabolismo , Acetilação , Carcinogênese/metabolismo , Diferenciação Celular/fisiologia , Núcleo Celular/metabolismo , Proliferação de Células/fisiologia , Transformação Celular Neoplásica/metabolismo , Cromatina/metabolismo , Células-Tronco Embrionárias/metabolismo , Células-Tronco Embrionárias/fisiologia , Histonas/metabolismo , Humanos , Neoplasias Pulmonares/metabolismo , Proteínas Nucleares/metabolismo , Processamento de Proteína Pós-Traducional
19.
PLoS One ; 15(7): e0234614, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32649728

RESUMO

Exosomes appear to be effective inter-cellular communicators delivering several types of molecules, such as proteins and RNAs, suggesting that they could influence neural stem cell (NSC) differentiation. Our RNA sequencing studies demonstrated that the RNAs related to cell proliferation and astrocyte differentiation were upregulated in human mesenchymal stem cells (hMSC) when co-cultured with exosomes obtained from the culture medium of human glioma cells (U87). Metallothionein 3 and elastin genes, which are related to cell proliferation, increased 10 and 7.2 fold, respectively. Expression of genes for astrocyte differentiation, such as tumor growth factor alpha, induced protein 3 of the NOTCH1 family, colony stimulating factor and interleukin 6 of the STAT3 family and Hes family bHLH transcription factor 1 also increased by 2.3, 10, 4.7 and 2.9 fold, respectively. We further examined the effects of these exosomes on rat fetal neural stem cell (rNSC) differentiation using the secreted exosomes from U87 glioma cells or exosomes from U87 cells that were stimulated with interleukin 1ß (IL-1ß). The rNSCs, extracted from rat brains at embryonic day 14 (E14), underwent a culture protocol that normally leads to predominant (~90%) differentiation to ODCs. However, in the presence of the exosomes from untreated or IL-1ß-treated U87 cells, significantly more cells differentiated into astrocytes, especially in the presence of exosomes obtained from the IL-1ß-challenged glioma cells. Moreover, glioma-derived exosomes appeared to inhibit rNSC differentiation into ODCs or astrocytes as indicated by a significantly increased population of unlabeled cells. A portion of the resulting astrocytes co-expressed both CD133 and glial fibrillary acidic protein (GFAP) suggesting that exosomes from U87 cells could promote astrocytic differentiation of NSCs with features expected from a transformed cell. Our data clearly demonstrated that exosomes secreted by human glioma cells provide a strong driving force for rat neural stem cells to differentiate into astrocytes, uncovering potential pathways and therapeutic targets that might control this aggressive tumor type.


Assuntos
Astrócitos/metabolismo , Diferenciação Celular/fisiologia , Exossomos/fisiologia , Células-Tronco Neurais/metabolismo , Animais , Astrócitos/fisiologia , Proliferação de Células , Células Cultivadas , Técnicas de Cocultura , Elastina/metabolismo , Exossomos/metabolismo , Regulação da Expressão Gênica/genética , Glioma/metabolismo , Humanos , Interleucina-6/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Células-Tronco Neurais/fisiologia , Neurônios/metabolismo , Cultura Primária de Células , Ratos , Fator de Transcrição STAT3/metabolismo
20.
Nat Commun ; 11(1): 3760, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32724077

RESUMO

Human embryogenesis is hallmarked by two phases of yolk sac development. The primate hypoblast gives rise to a transient primary yolk sac, which is rapidly superseded by a secondary yolk sac during gastrulation. Moreover, primate embryos form extraembryonic mesoderm prior to gastrulation, in contrast to mouse. The function of the primary yolk sac and the origin of extraembryonic mesoderm remain unclear. Here, we hypothesise that the hypoblast-derived primary yolk sac serves as a source for early extraembryonic mesoderm, which is supplemented with mesoderm from the gastrulating embryo. We discuss the intricate relationship between the yolk sac and the primate embryo and highlight the pivotal role of the yolk sac as a multifunctional hub for haematopoiesis, germ cell development and nutritional supply.


Assuntos
Desenvolvimento Embrionário/fisiologia , Mesoderma/embriologia , Primatas/embriologia , Saco Vitelino/embriologia , Animais , Diferenciação Celular/fisiologia , Células Germinativas Embrionárias/fisiologia , Hematopoese/fisiologia
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