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1.
Immunity ; 48(2): 187-190, 2018 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-29466747

RESUMEN

Immune surveillance is an established regulatory mechanism that spares tissues from malignant transformation. Agudo et al. (2018) find that the chief cell type to generate tissues in the body-somatic stem cells-is subject to immune surveillance only during proliferation.


Asunto(s)
Ciclo Celular , Células Madre , Transformación Celular Neoplásica , Humanos , Vigilancia Inmunológica
2.
Opt Lett ; 49(5): 1297-1300, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38426997

RESUMEN

The successful demonstration of long-lived nitric oxide (NO) fluorescence for molecular tagging velocimetry (MTV) measurements is described in this Letter. Using 1 + 1 resonance-enhanced multiphoton ionization (REMPI) of NO at a wavelength near 226 nm, targeting the overlapping Q1(7) and Q21(7) lines of the A-X (0, 0) electronic system, the lifetime of the NO MTV signal was observed to be approximately 8.6 µs within a 100-Torr cell containing 2% NO in nitrogen. This is in stark contrast to the commonly reported single photon NO fluorescence, which has a much shorter calculated lifetime of approximately 43 ns at this pressure and NO volume fraction. While the shorter lifetime fluorescence can be useful for molecular tagging velocimetry with single laser excitation within very high-speed flows at some thermodynamic conditions, the longer lived fluorescence shows the potential for an order of magnitude more accurate and precise velocimetry, particularly within lower speed regions of hypersonic flow fields such as wakes and boundary layers. The physical mechanism responsible for the generation of this long-lived signal is detailed. Furthermore, the effectiveness of this technique is showcased in a high-speed jet flow, where it is employed for precise flow velocity measurements.

3.
Appl Opt ; 63(5): 1247-1257, 2024 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-38437304

RESUMEN

An injection-seeded, burst-mode optical parametric oscillator (OPO) operating at a repetition rate of 100 kHz is used to demonstrate the multiline molecular tagging velocimetry of an underexpanded jet using nitric oxide fluorescence. The very narrow linewidth of the OPO system, along with the relatively high pulse energies of the burst-mode system, enables efficient single-photon excitation of nitric oxide along multiple laser beam lines at a high repetition rate. Simultaneous one-dimensional velocity profile measurements were obtained of an underexpanded jet system at six different locations using a reference initial image and single-shot delayed images. A methodology for calculating the uncertainty of single-shot velocity is also described. Mean and root-mean-square velocity profiles are obtained at multiple locations simultaneously over a sampling time of 1 ms. The high-repetition-rate velocity measurements also appear to capture the onset of velocity oscillations and has the potential to reveal velocity frequency content occurring in the tens of kHz. The demonstrated velocimetry technique could be paired with other emerging burst-mode laser capabilities for a quantitative multiparameter gas property or multicomponent gas velocity measurements for supersonic and hypersonic flows, especially within ground test facilities that are limited to very short run durations.

4.
Appl Opt ; 61(1): 28-34, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-35200798

RESUMEN

Gas density distributions for an underexpanded jet at several different pressure ratios were measured at ultrahigh speeds in this work using digital holographic interferometry (DHI). DHI measurements have generally been performed on the order of several Hz in the literature, although some recent groups report measurements at 10 and 100 kHz. We demonstrate 2D imaging of gas density distributions at imaging rates up to 5 MHz, which is an increase by a factor of 50 compared to the previous DHI literature. A narrow-linewidth, continuous-wave laser was used in a Mach-Zehnder configuration, and the holograms were recorded using one of two different CMOS cameras. The interferograms were analyzed using the Fourier method, and a phase unwrapping was performed. Axisymmetric flow was assumed for the region near the nozzle exit, and an Abel inversion was performed to generate a planar-slice gas density distribution from the line-of-sight unwrapped phase. The challenges and opportunities associated with performing DHI measurements at ultrahigh speeds are discussed.

5.
Dev Biol ; 424(2): 236-245, 2017 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-28189604

RESUMEN

Hematopoietic stem cells (HSCs) emerge during development via an endothelial-to-hematopoietic transition from hemogenic endothelium of the dorsal aorta (DA). Using in situ hybridization and analysis of a knock-in RedStar reporter, we show that the transcriptional regulator Hhex is expressed in endothelium of the dorsal aorta (DA) and in clusters of putative HSCs as they are specified during murine development. We exploited this observation, using the Hhex locus to define cis regulatory elements, enhancers and interacting transcription factors that are both necessary and sufficient to support gene expression in the emerging HSC. We identify an evolutionarily conserved non-coding region (ECR) in the Hhex locus with the capacity to bind the hematopoietic-affiliated transcriptional regulators Gata2, SCL, Fli1, Pu.1 and Ets1/2. This region is sufficient to drive the expression of a transgenic GFP reporter in the DA endothelium and intra-aortic hematopoietic clusters. GFP-positive AGM cells co-expressed HSC-associated markers c-Kit, CD34, VE-Cadherin, and CD45, and were capable of multipotential differentiation and long term engraftment when transplanted into myelo-ablated recipients. The Hhex ECR was also sufficient to drive expression at additional blood sites including the yolk sac blood islands, fetal liver, vitelline and umbilical arteries and the adult bone marrow, suggesting a common mechanism for Hhex regulation throughout ontogenesis of the blood system. To explore the physiological requirement for the Hhex ECR region during hematoendothelial development, we deleted the ECR element from the endogenous locus in the context of a targeted Hhex-RedStar reporter allele. Results indicate a specific requirement for the ECR in blood-associated Hhex expression during development and further demonstrate a requirement for this region in the adult HSC compartment. Taken together, our results identified the ECR region as an enhancer both necessary and sufficient for gene expression in HSC development and homeostasis. The Hhex ECR thus appears to be a core node for the convergence of the transcription factor network that governs the emergence of HSCs.


Asunto(s)
Regulación de la Expresión Génica , Hematopoyesis/genética , Células Madre Hematopoyéticas/metabolismo , Proteínas de Homeodominio/metabolismo , Factores de Transcripción/metabolismo , Transcripción Genética , Animales , Compartimento Celular , Linaje de la Célula/genética , Ensayo de Unidades Formadoras de Colonias , Secuencia Conservada/genética , Embrión de Mamíferos/metabolismo , Sitios Genéticos , Proteínas Fluorescentes Verdes/metabolismo , Células Madre Hematopoyéticas/citología , Proteínas de Homeodominio/genética , Ratones Endogámicos C57BL , Ratones Transgénicos , Secuencias Reguladoras de Ácidos Nucleicos/genética , Factores de Transcripción/genética
6.
Exp Hematol ; 134: 104177, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38336135

RESUMEN

Emerging evidence implicates the epithelial-mesenchymal transition transcription factor Zeb1 as a critical regulator of hematopoietic stem cell (HSC) differentiation. Whether Zeb1 regulates long-term maintenance of HSC function remains an open question. Using an inducible Mx-1-Cre mouse model that deletes conditional Zeb1 alleles in the adult hematopoietic system, we found that mice engineered to be deficient in Zeb1 for 32 weeks displayed expanded immunophenotypically defined adult HSCs and multipotent progenitors associated with increased abundance of lineage-biased/balanced HSC subsets and augmented cell survival characteristics. During hematopoietic differentiation, persistent Zeb1 loss increased B cells in the bone marrow and spleen and decreased monocyte generation in the peripheral blood. In competitive transplantation experiments, we found that HSCs from adult mice with long-term Zeb1 deletion displayed a cell autonomous defect in multilineage differentiation capacity. Long-term Zeb1 loss perturbed extramedullary hematopoiesis characterized by increased splenic weight and a paradoxical reduction in splenic cellularity that was accompanied by HSC exhaustion, lineage-specific defects, and an accumulation of aberrant, preleukemic like c-kit+CD16/32+ progenitors. Loss of Zeb1 for up to 42 weeks can lead to progressive splenomegaly and an accumulation of Gr-1+Mac-1+ cells, further supporting the notion that long-term expression of Zeb1 suppresses preleukemic activity. Thus, sustained Zeb1 deletion disrupts HSC functionality in vivo and impairs regulation of extramedullary hematopoiesis with potential implications for tumor suppressor functions of Zeb1 in myeloid neoplasms.


Asunto(s)
Hematopoyesis Extramedular , Células Madre Hematopoyéticas , Homeobox 1 de Unión a la E-Box con Dedos de Zinc , Animales , Homeobox 1 de Unión a la E-Box con Dedos de Zinc/genética , Homeobox 1 de Unión a la E-Box con Dedos de Zinc/metabolismo , Ratones , Células Madre Hematopoyéticas/metabolismo , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/patología , Hematopoyesis Extramedular/genética , Diferenciación Celular , Ratones Noqueados , Bazo/metabolismo , Bazo/patología , Bazo/citología , Células Madre Adultas/metabolismo , Linaje de la Célula
7.
Stem Cells ; 30(5): 797-803, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22419544

RESUMEN

Autologous-induced pluripotent stem cells (iPSCs) may eventually be used in cell replacement therapies to treat a wide range of diseases and have been touted as a solution to the vexing problem of immune rejection in this context. Emerging evidence suggests, however, that ostensibly histocompatible iPSCs may be rejected following transplantation. Here, we review the mechanisms that contribute to immunogenicity in iPSCs and forward approaches to permit their acceptance in potential cell replacement therapies.


Asunto(s)
Rechazo de Injerto/inmunología , Células Madre Pluripotentes Inducidas/inmunología , Células Madre Pluripotentes Inducidas/trasplante , Trasplante de Células Madre , Animales , Humanos
8.
Nature ; 447(7145): 686-90, 2007 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-17554302

RESUMEN

Accumulation of DNA damage leading to adult stem cell exhaustion has been proposed to be a principal mechanism of ageing. Here we address this question by taking advantage of the highly specific role of DNA ligase IV in the repair of DNA double-strand breaks by non-homologous end-joining, and by the discovery of a unique mouse strain with a hypomorphic Lig4(Y288C) mutation. The Lig4(Y288C) mouse, identified by means of a mutagenesis screening programme, is a mouse model for human LIG4 syndrome, showing immunodeficiency and growth retardation. Diminished DNA double-strand break repair in the Lig4(Y288C) strain causes a progressive loss of haematopoietic stem cells and bone marrow cellularity during ageing, and severely impairs stem cell function in tissue culture and transplantation. The sensitivity of haematopoietic stem cells to non-homologous end-joining deficiency is therefore a key determinant of their ability to maintain themselves against physiological stress over time and to withstand culture and transplantation.


Asunto(s)
Envejecimiento/fisiología , Reparación del ADN , Células Madre Hematopoyéticas/citología , Animales , Proliferación Celular , Senescencia Celular/fisiología , Roturas del ADN de Doble Cadena , Daño del ADN , ADN Ligasa (ATP) , ADN Ligasas/deficiencia , ADN Ligasas/genética , ADN Ligasas/metabolismo , Células Madre Hematopoyéticas/patología , Humanos , Ratones , Ratones Endogámicos C57BL , Mutación Missense/efectos de los fármacos , Mutación Missense/genética , Síndrome
9.
Biomolecules ; 13(9)2023 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-37759786

RESUMEN

Zeb1, a zinc finger E-box binding homeobox epithelial-mesenchymal (EMT) transcription factor, acts as a critical regulator of hematopoietic stem cell (HSC) self-renewal and multi-lineage differentiation. Whether Zeb1 directly regulates the function of multi-potent progenitors primed for hematopoietic lineage commitment remains ill defined. By using an inducible Mx-1 Cre conditional mouse model where Zeb1 was genetically engineered to be deficient in the adult hematopoietic system (hereafter Zeb1-/-), we found that the absolute cell number of immunophenotypically defined lympho-myeloid primed progenitors (LMPPs) from Zeb1-/- mice was reduced. Myeloid- and lymphoid-biased HSCs in Zeb1-/- mice were unchanged, implying that defective LMPP generation from Zeb1-/- mice was not directly caused by an imbalance of lineage-biased HSCs. Functional analysis of LMPP from Zeb1-/- mice, as judged by competitive transplantation, revealed an overall reduction in engraftment to hematopoietic organs over 4 weeks, which correlated with minimal T-cell engraftment, reduced B-cell and monocyte/macrophage engraftment, and unperturbed granulocyte engraftment. Thus, Zeb1 regulates LMPP differentiation potential to select lympho-myeloid lineages in the context of transplantation.

10.
Mol Nutr Food Res ; 67(14): e2200716, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37150886

RESUMEN

SCOPE: A prospective study of 34492 participants shows an inverse association between (+)-catechin intake and coronary heart disease. The effects of (+)-catechin on atherosclerosis and associated risk factors are poorly understood and are investigated. METHODS AND RESULTS: (+)-Catechin attenuates reactive oxygen species production in human macrophages, endothelial cells and vascular smooth muscle cells, chemokine-driven monocytic migration, and proliferation of human macrophages and their expression of several pro-atherogenic genes. (+)-Catechin also improves oxidized LDL-mediated mitochondrial membrane depolarization in endothelial cells and attenuates growth factor-induced smooth muscle cell migration. In C57BL/6J mice fed high fat diet (HFD) for 3 weeks, (+)-catechin attenuates plasma levels of triacylglycerol and interleukin (IL)-1ß and IL-2, produces anti-atherogenic changes in liver gene expression, and reduces levels of white blood cells, myeloid-derived suppressor cells, Lin- Sca+ c-Kit+ cells, and common lymphoid progenitor cells within the bone marrow. In LDL receptor deficient mice fed HFD for 12 weeks, (+)-catechin attenuates atherosclerotic plaque burden and inflammation with reduced macrophage content and increased markers of plaque stability; smooth muscle cell and collagen content. CONCLUSION: This study provides novel, detailed insights into the cardio-protective actions of (+)-catechin together with underlying molecular mechanisms and supports further assessments of its beneficial effects in human trials.


Asunto(s)
Aterosclerosis , Catequina , Placa Aterosclerótica , Humanos , Ratones , Animales , Placa Aterosclerótica/metabolismo , Catequina/farmacología , Catequina/metabolismo , Células Endoteliales/metabolismo , Ratones Endogámicos C57BL , Estudios Prospectivos , Ratones Noqueados , Aterosclerosis/metabolismo , Inflamación/metabolismo , Receptores de LDL/metabolismo , Factores de Riesgo
11.
Leukemia ; 37(2): 276-287, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36572750

RESUMEN

Nuclear factor I-C (NFIC) belongs to a family of NFI transcription factors that binds to DNA through CAATT-boxes and are involved in cellular differentiation and stem cell maintenance. Here we show NFIC protein is significantly overexpressed in 69% of acute myeloid leukemia patients. Examination of the functional consequences of NFIC overexpression in HSPCs showed that this protein promoted monocytic differentiation. Single-cell RNA sequencing analysis further demonstrated that NFIC overexpressing monocytes had increased expression of growth and survival genes. In contrast, depletion of NFIC through shRNA decreased cell growth, increased cell cycle arrest and apoptosis in AML cell lines and AML patient blasts. Further, in AML cell lines (THP-1), bulk RNA sequencing of NFIC knockdown led to downregulation of genes involved in cell survival and oncogenic signaling pathways including mixed lineage leukemia-1 (MLL-1). Lastly, we show that NFIC knockdown in an ex vivo mouse MLL::AF9 pre-leukemic stem cell model, decreased their growth and colony formation and increased expression of myeloid differentiation markers Gr1 and Mac1. Collectively, our results suggest that NFIC is an important transcription factor in myeloid differentiation as well as AML cell survival and is a potential therapeutic target in AML.


Asunto(s)
Leucemia Mieloide Aguda , Factores de Transcripción NFI , Animales , Ratones , Diferenciación Celular/fisiología , Supervivencia Celular/genética , Hematopoyesis , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Proteína de la Leucemia Mieloide-Linfoide/genética , Factores de Transcripción NFI/metabolismo
12.
Methods Mol Biol ; 2419: 73-88, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35237959

RESUMEN

Outgrowth of a mutated hematopoietic stem/progenitor clone and its descendants, also known as clonal hematopoiesis, has long been considered as either a potential forerunner to hematologic malignancy or as a clinically silent phase in leukemia that antedates symptomatic disease. That definition of clonal hematopoiesis has now been expanded to encompass patients who harbor specific genetic/epigenetic mutations that lead to clonal hematopoiesis of indeterminate potential (CHIP) and, with it, a relatively heightened risk for both myeloid malignancy and atherosclerosis during aging. In this review, we provide contemporary insights into the cellular and molecular basis for CHIP and explore the relationship of CHIP to myeloid malignancy and atherosclerosis. We also discuss emerging strategies to explore CHIP biology and clinical targeting of CHIP related malignancy and cardiovascular disease.


Asunto(s)
Aterosclerosis , Leucemia , Neoplasias , Aterosclerosis/genética , Aterosclerosis/patología , Hematopoyesis Clonal/genética , Hematopoyesis/genética , Células Madre Hematopoyéticas/patología , Humanos , Leucemia/patología , Mutación , Neoplasias/genética
13.
Methods Mol Biol ; 2419: 583-595, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35237990

RESUMEN

Advancing age causes physiologic decline in tissue function. In the hematopoietic system this manifests as a progressive reduction in blood or immune cell function and clonal hematopoiesis, where a mutated hematopoietic stem cell can dominate blood cell production and confer an increased propensity for myeloid malignancy. In the aging cardiovascular system, atherosclerosis causes an inflammatory cell- driven accumulation of lipid-derived plaques in major arteries which constrains blood flow and can lead to myocardial infarction and stroke. Clonal hematopoiesis in the elderly has recently been associated with a substantially increased risk of atherosclerosis-related cardiovascular disease. However, the direct association between deregulated hematopoiesis in clonal hematopoiesis and atherosclerosis is poorly defined. Herein, we describe a flow cytometry method to prospectively analyze the crucial hematopoietic stem/progenitor, inflammatory and lymphoid cell participants in atherosclerosis. This analysis can be applied to decipher the complex relationship between hematopoietic cell types involved in clonal hematopoiesis and atherosclerosis in mouse models.


Asunto(s)
Aterosclerosis , Células Madre Hematopoyéticas , Animales , Aterosclerosis/patología , Células Sanguíneas/metabolismo , Citometría de Flujo , Hematopoyesis , Células Madre Hematopoyéticas/metabolismo , Ratones
14.
Blood ; 113(12): 2661-72, 2009 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-19168794

RESUMEN

Evidence suggests the transcription factor GATA-2 is a critical regulator of murine hematopoietic stem cells. Here, we explore the relation between GATA-2 and cell proliferation and show that inducing GATA-2 increases quiescence (G(0) residency) of murine and human hematopoietic cells. In human cord blood, quiescent fractions (CD34(+)CD38(-)Hoechst(lo)Pyronin Y(lo)) express more GATA-2 than cycling counterparts. Enforcing GATA-2 expression increased quiescence of cord blood cells, reducing proliferation and performance in long-term culture-initiating cell and colony-forming cell (CFC) assays. Gene expression analysis places GATA-2 upstream of the quiescence regulator MEF, but enforcing MEF expression does not prevent GATA-2-conferred quiescence, suggesting additional regulators are involved. Although known quiescence regulators p21(CIP1) and p27(KIP1) do not appear to be responsible, enforcing GATA-2 reduced expression of regulators of cell cycle such as CCND3, CDK4, and CDK6. Enforcing GATA-2 inhibited human hematopoiesis in vivo: cells with highest exogenous expression (GATA-2(hi)) failed to contribute to hematopoiesis in nonobese diabetic-severe combined immunodeficient (NOD-SCID) mice, whereas GATA-2(lo) cells contributed with delayed kinetics and low efficiency, with reduced expression of Ki-67. Thus, GATA-2 activity inhibits cell cycle in vitro and in vivo, highlighting GATA-2 as a molecular entry point into the transcriptional program regulating quiescence in human hematopoietic stem and progenitor cells.


Asunto(s)
Ciclo Celular , Factor de Transcripción GATA2/fisiología , Células Madre Hematopoyéticas/citología , Animales , Apoptosis , Células Cultivadas/citología , Células Cultivadas/efectos de los fármacos , Trasplante de Células Madre de Sangre del Cordón Umbilical , Estradiol/farmacología , Sangre Fetal/citología , Factor de Transcripción GATA2/biosíntesis , Factor de Transcripción GATA2/genética , Regulación de la Expresión Génica/genética , Genes Sintéticos , Genes cdc , Humanos , Interleucina-3/farmacología , Ratones , Ratones Endogámicos NOD , Ratones SCID , Receptores de Estrógenos/efectos de los fármacos , Receptores de Estrógenos/genética , Proteínas Recombinantes de Fusión/fisiología , Fase de Descanso del Ciclo Celular , Tamoxifeno/farmacología , Transcripción Genética
15.
Blood Adv ; 5(20): 4285-4290, 2021 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-34496012

RESUMEN

During aging, hematopoietic stem cell (HSC) function wanes with important biological and clinical implications for benign and malignant hematology, and other comorbidities, such as cardiovascular disease. However, the molecular mechanisms regulating HSC aging remain incompletely defined. GATA2 haploinsufficiency driven clinical syndromes initially result in primary immunodeficiencies and routinely evolve into hematologic malignancies on acquisition of further epigenetic mutations in both young and older patients. Using a conditional mouse model of Gata2 haploinsufficiency, we discover that during aging Gata2 promotes HSC proliferation, monocytosis, and loss of the common lymphoid progenitor. Aging of Gata2 haploinsufficient mice also offsets enhanced HSC apoptosis and decreased granulocyte-macrophage progenitor number normally observed in young Gata2 haploinsufficient mice. Transplantation of elderly Gata2 haploinsufficient HSCs impairs HSC function with evidence of myeloid bias. Our data demonstrate that Gata2 regulates HSC aging and suggest the mechanisms by which Gata2 mediated HSC aging has an impact on the evolution of malignancies in GATA2 haploinsufficiency syndromes.


Asunto(s)
Deficiencia GATA2 , Anciano , Envejecimiento/genética , Animales , Proliferación Celular , Factor de Transcripción GATA2/genética , Hematopoyesis , Células Madre Hematopoyéticas , Humanos , Ratones
16.
Mol Nutr Food Res ; 65(17): e2100214, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34216185

RESUMEN

SCOPE: Previous studies show that Lab4 probiotic consortium plus Lactobacillus plantarum CUL66 (Lab4P) reduces diet-induced weight gain and plasma cholesterol levels in C57BL/6J mice fed a high fat diet (HFD). The effect of Lab4P on atherosclerosis is not known and is therefore investigated. METHODS AND RESULTS: Atherosclerosis-associated parameters are analyzed in LDL receptor deficient mice fed HFD for 12 weeks alone or supplemented with Lab4P. Lab4P increases plasma HDL and triglyceride levels and decreases LDL/VLDL levels. Lab4P also reduces plaque burden and content of lipids and macrophages, indicative of dampened inflammation, and increases smooth muscle cell content, a marker of plaque stabilization. Atherosclerosis arrays show that Lab4P alters the liver expression of 19 key disease-associated genes. Lab4P also decreases the frequency of macrophages and T-cells in the bone marrow. In vitro assays using conditioned media from probiotic bacteria demonstrates attenuation of several atherosclerosis-associated processes in vitro such as chemokine-driven monocytic migration, proliferation of monocytes and macrophages, foam cell formation and associated changes in expression of key genes, and proliferation and migration of vascular smooth muscle cells. CONCLUSION: This study provides new insights into the anti-atherogenic actions of Lab4P together with the underlying mechanisms and supports further assessments in human trials.


Asunto(s)
Aterosclerosis/terapia , Hígado/fisiología , Placa Aterosclerótica/terapia , Probióticos/farmacología , Animales , Aterosclerosis/genética , Aterosclerosis/patología , Células de la Médula Ósea , Colesterol/sangre , Medios de Cultivo Condicionados/farmacología , Dieta Alta en Grasa/efectos adversos , Regulación de la Expresión Génica , Lactobacillus plantarum , Lípidos/sangre , Masculino , Ratones Mutantes , Tamaño de los Órganos , Placa Aterosclerótica/patología , Receptores de LDL/genética , Bazo/crecimiento & desarrollo
17.
Food Funct ; 12(8): 3657-3671, 2021 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-33900312

RESUMEN

Atherosclerosis, an inflammatory disorder of the vasculature and the underlying cause of cardiovascular disease, is responsible for one in three global deaths. Consumption of active food ingredients such as omega-3 polyunsaturated fatty acids, flavanols and phytosterols has many beneficial effects on cardiovascular disease. However, their combined actions on the risk factors for atherosclerosis remains poorly understood. We have previously shown that a formulation containing each of these active components at physiologically relevant doses modulated several monocyte/macrophage processes associated with atherosclerosis in vitro, including inhibition of cytokine-induced pro-inflammatory gene expression, chemokine-driven monocyte migration, expression of M1 phenotype markers, and promotion of cholesterol efflux. The objectives of the present study were to investigate whether the protective actions of the formulation extended in vivo and to delineate the potential underlying mechanisms. The formulation produced several favourable changes, including higher plasma levels of HDL and reduced levels of macrophages and myeloid-derived suppressor cells in the bone marrow. The mRNA expression of liver-X-receptor-α, peroxisome proliferator-activated receptor-γ and superoxide dismutase-1 was induced in the liver and that of interferon-γ and the chemokine (C-X-C motif) ligand 1 decreased, thereby suggesting the potential mechanisms for many beneficial effects. Other changes were also observed such as increased plasma levels of triglycerides and lipid peroxidation that may reflect potential activation of brown fat. This study provides new insights into the protective actions and the potential underlying mechanisms of the formulation in vivo, particularly in relation to risk factors together with changes in systemic inflammation and hepatic lipid alterations associated with atherosclerosis and metabolic syndrome, and supports further assessments in human trials.


Asunto(s)
Cardiotónicos/farmacología , Enfermedad de la Arteria Coronaria/prevención & control , Animales , Cardiotónicos/administración & dosificación , Dieta Alta en Grasa , Modelos Animales de Enfermedad , Ácidos Grasos Omega-3/administración & dosificación , Flavanonas/administración & dosificación , Alimentos Funcionales , Expresión Génica , Masculino , Ratones , Ratones Endogámicos C57BL , Fitosteroles/administración & dosificación , Factores de Riesgo
18.
Stem Cell Reports ; 16(11): 2784-2797, 2021 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-34715054

RESUMEN

Hematopoietic stem cells (HSCs) reside at the apex of the hematopoietic differentiation hierarchy and sustain multilineage hematopoiesis. Here, we show that the transcriptional regulator CITED2 is essential for life-long HSC maintenance. While hematopoietic-specific Cited2 deletion has a minor impact on steady-state hematopoiesis, Cited2-deficient HSCs are severely depleted in young mice and fail to expand upon aging. Moreover, although they home normally to the bone marrow, they fail to reconstitute hematopoiesis upon transplantation. Mechanistically, CITED2 is required for expression of key HSC regulators, including GATA2, MCL-1, and PTEN. Hematopoietic-specific expression of anti-apoptotic MCL-1 partially rescues the Cited2-deficient HSC pool and restores their reconstitution potential. To interrogate the Cited2→Pten pathway in HSCs, we generated Cited2;Pten compound heterozygous mice, which had a decreased number of HSCs that failed to reconstitute the HSC compartment. In addition, CITED2 represses multiple pathways whose elevated activity causes HSC exhaustion. Thus, CITED2 promotes pathways necessary for HSC maintenance and suppresses those detrimental to HSC integrity.


Asunto(s)
Regulación de la Expresión Génica , Hematopoyesis/genética , Trasplante de Células Madre Hematopoyéticas/métodos , Células Madre Hematopoyéticas/metabolismo , Proteínas Represoras/genética , Transactivadores/genética , Animales , Apoptosis/genética , Proliferación Celular/genética , Redes Reguladoras de Genes/genética , Ratones Endogámicos C57BL , Ratones Noqueados , RNA-Seq/métodos , Proteínas Represoras/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal/genética , Factores de Tiempo , Transactivadores/metabolismo
19.
Blood Adv ; 5(3): 889-899, 2021 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-33560400

RESUMEN

Lifelong multilineage hematopoiesis critically depends on rare hematopoietic stem cells (HSCs) that reside in the hypoxic bone marrow microenvironment. Although the role of the canonical oxygen sensor hypoxia-inducible factor prolyl hydroxylase has been investigated extensively in hematopoiesis, the functional significance of other members of the 2-oxoglutarate (2-OG)-dependent protein hydroxylase family of enzymes remains poorly defined in HSC biology and multilineage hematopoiesis. Here, by using hematopoietic-specific conditional gene deletion, we reveal that the 2-OG-dependent protein hydroxylase JMJD6 is essential for short- and long-term maintenance of the HSC pool and multilineage hematopoiesis. Additionally, upon hematopoietic injury, Jmjd6-deficient HSCs display a striking failure to expand and regenerate the hematopoietic system. Moreover, HSCs lacking Jmjd6 lose multilineage reconstitution potential and self-renewal capacity upon serial transplantation. At the molecular level, we found that JMJD6 functions to repress multiple processes whose downregulation is essential for HSC integrity, including mitochondrial oxidative phosphorylation (OXPHOS), protein synthesis, p53 stabilization, cell cycle checkpoint progression, and mTORC1 signaling. Indeed, Jmjd6-deficient primitive hematopoietic cells display elevated basal and maximal mitochondrial respiration rates and increased reactive oxygen species (ROS), prerequisites for HSC failure. Notably, an antioxidant, N-acetyl-l-cysteine, rescued HSC and lymphoid progenitor cell depletion, indicating a causal impact of OXPHOS-mediated ROS generation upon Jmjd6 deletion. Thus, JMJD6 promotes HSC maintenance and multilineage differentiation potential by suppressing fundamental pathways whose activation is detrimental for HSC function.


Asunto(s)
Hematopoyesis , Células Madre Hematopoyéticas , Médula Ósea , Trasplante de Médula Ósea , Diferenciación Celular
20.
J Clin Invest ; 131(1)2021 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-33108352

RESUMEN

Zeb1, a zinc finger E-box binding homeobox epithelial-mesenchymal transition (EMT) transcription factor, confers properties of "stemness," such as self-renewal, in cancer. Yet little is known about the function of Zeb1 in adult stem cells. Here, we used the hematopoietic system as a well-established paradigm of stem cell biology to evaluate Zeb1-mediated regulation of adult stem cells. We employed a conditional genetic approach using the Mx1-Cre system to specifically knock out (KO) Zeb1 in adult hematopoietic stem cells (HSCs) and their downstream progeny. Acute genetic deletion of Zeb1 led to rapid-onset thymic atrophy and apoptosis-driven loss of thymocytes and T cells. A profound cell-autonomous self-renewal defect and multilineage differentiation block were observed in Zeb1-KO HSCs. Loss of Zeb1 in HSCs activated transcriptional programs of deregulated HSC maintenance and multilineage differentiation genes and of cell polarity consisting of cytoskeleton-, lipid metabolism/lipid membrane-, and cell adhesion-related genes. Notably, epithelial cell adhesion molecule (EpCAM) expression was prodigiously upregulated in Zeb1-KO HSCs, which correlated with enhanced cell survival, diminished mitochondrial metabolism, ribosome biogenesis, and differentiation capacity and an activated transcriptomic signature associated with acute myeloid leukemia (AML) signaling. ZEB1 expression was downregulated in AML patients, and Zeb1 KO in the malignant counterparts of HSCs - leukemic stem cells (LSCs) - accelerated MLL-AF9- and Meis1a/Hoxa9-driven AML progression, implicating Zeb1 as a tumor suppressor in AML LSCs. Thus, Zeb1 acts as a transcriptional regulator in hematopoiesis, critically coordinating HSC self-renewal, apoptotic, and multilineage differentiation fates required to suppress leukemic potential in AML.


Asunto(s)
Células Madre Hematopoyéticas/metabolismo , Leucemia Mieloide Aguda/metabolismo , Células Madre Neoplásicas/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Homeobox 1 de Unión a la E-Box con Dedos de Zinc/metabolismo , Animales , Eliminación de Gen , Células Madre Hematopoyéticas/patología , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Ratones , Ratones Noqueados , Células Madre Neoplásicas/patología , Proteínas Supresoras de Tumor/genética , Homeobox 1 de Unión a la E-Box con Dedos de Zinc/genética
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