Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
1.
FASEB J ; 38(14): e23815, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-38989587

RESUMEN

To investigate how the fatty acid composition of brain phospholipids influences brain-specific processes, we leveraged the AdipoR2 (adiponectin receptor 2) knockout mouse model in which the brain is enlarged, and cellular membranes are excessively rich in saturated fatty acids. Lipidomics analysis of brains at 2, 7, and 18 months of age showed that phosphatidylcholines, which make up about two-thirds of all cerebrum membrane lipids, contain a gross excess of saturated fatty acids in AdipoR2 knockout mice, and that this is mostly attributed to an excess palmitic acid (C16:0) at the expense of oleic acid (C18:1), consistent with a defect in fatty acid desaturation and elongation in the mutant. Specifically, there was a ~12% increase in the overall saturated fatty acid content within phosphatidylcholines and a ~30% increase in phosphatidylcholines containing two palmitic acids. Phosphatidylethanolamines, sphingomyelins, ceramides, lactosylceramides, and dihydroceramides also showed an excess of saturated fatty acids in the AdipoR2 knockout mice while nervonic acid (C24:1) was enriched at the expense of shorter saturated fatty acids in glyceroceramides. Similar defects were found in the cerebellum and myelin sheaths. Histology showed that cell density is lower in the cerebrum of AdipoR2 knockout mice, but electron microscopy did not detect reproducible defects in the ultrastructure of cerebrum neurons, though proteomics analysis showed an enrichment of electron transport chain proteins in the cerebellum. Behavioral tests showed that older (33 weeks old) AdipoR2 knockout mice are hyperactive and anxious compared to control mice of a similar age. Also, in contrast to control mice, the AdipoR2 knockout mice do not gain weight in old age but do have normal lifespans. We conclude that an excess fatty acid saturation in brain phospholipids is accompanied by hyperactivity but seems otherwise well tolerated.


Asunto(s)
Envejecimiento , Encéfalo , Ácidos Grasos , Ratones Noqueados , Receptores de Adiponectina , Animales , Ratones , Encéfalo/metabolismo , Ácidos Grasos/metabolismo , Envejecimiento/metabolismo , Receptores de Adiponectina/metabolismo , Receptores de Adiponectina/genética , Masculino , Ratones Endogámicos C57BL , Fosfatidilcolinas/metabolismo , Fosfolípidos/metabolismo
2.
Hum Mol Genet ; 28(8): 1286-1297, 2019 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-30561639

RESUMEN

Molecular mechanisms governing the development of the human cochlea remain largely unknown. Through genome sequencing, we identified a homozygous FOXF2 variant c.325A>T (p.I109F) in a child with profound sensorineural hearing loss (SNHL) associated with incomplete partition type I anomaly of the cochlea. This variant is not found in public databases or in over 1000 ethnicity-matched control individuals. I109 is a highly conserved residue in the forkhead box (Fox) domain of FOXF2, a member of the Fox protein family of transcription factors that regulate the expression of genes involved in embryogenic development as well as adult life. Our in vitro studies show that the half-life of mutant FOXF2 is reduced compared to that of wild type. Foxf2 is expressed in the cochlea of developing and adult mice. The mouse knockout of Foxf2 shows shortened and malformed cochleae, in addition to altered shape of hair cells with innervation and planar cell polarity defects. Expressions of Eya1 and Pax3, genes essential for cochlear development, are reduced in the cochleae of Foxf2 knockout mice. We conclude that FOXF2 plays a major role in cochlear development and its dysfunction leads to SNHL and developmental anomalies of the cochlea in humans and mice.


Asunto(s)
Cóclea/embriología , Factores de Transcripción Forkhead/genética , Factores de Transcripción Forkhead/fisiología , Adulto , Animales , Niño , Cóclea/metabolismo , Cóclea/fisiología , Desarrollo Embrionario , Femenino , Células Ciliadas Auditivas/metabolismo , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Nucleares/genética , Proteínas Nucleares/fisiología , Organogénesis , Factor de Transcripción PAX3/genética , Factor de Transcripción PAX3/fisiología , Proteínas Tirosina Fosfatasas/genética , Proteínas Tirosina Fosfatasas/fisiología , Transducción de Señal/genética , Secuenciación Completa del Genoma
3.
Dev Biol ; 415(1): 14-23, 2016 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-27180663

RESUMEN

The secondary palate separates the oral from the nasal cavity and its closure during embryonic development is sensitive to genetic perturbations. Mice with deleted Foxf2, encoding a forkhead transcription factor, are born with cleft palate, and an abnormal tongue morphology has been proposed as the underlying cause. Here, we show that Foxf2(-/-) maxillary explants cultured in vitro, in the absence of tongue and mandible, failed to close the secondary palate. Proliferation and collagen content were decreased in Foxf2(-/-) palatal shelf mesenchyme. Phosphorylation of Smad2/3 was reduced in mutant palatal shelf, diagnostic of attenuated canonical Tgfß signaling, whereas phosphorylation of p38 was increased. The amount of Tgfß2 protein was diminished, whereas the Tgfb2 mRNA level was unaltered. Expression of several genes encoding extracellular proteins important for Tgfß signaling were reduced in Foxf2(-)(/)(-) palatal shelves: a fibronectin splice-isoform essential for formation of extracellular Tgfß latency complexes; Tgfbr3 - or betaglycan - which acts as a co-receptor and an extracellular reservoir of Tgfß; and integrins αV and ß1, which are both Tgfß targets and required for activation of latent Tgfß. Decreased proliferation and reduced extracellular matrix content are consistent with diminished Tgfß signaling. We therefore propose that gene expression changes in palatal shelf mesenchyme that lead to reduced Tgfß signaling contribute to cleft palate in Foxf2(-)(/)(-) mice.


Asunto(s)
Fisura del Paladar/embriología , Factores de Transcripción Forkhead/fisiología , Mesodermo/embriología , Hueso Paladar/embriología , Transducción de Señal/fisiología , Factor de Crecimiento Transformador beta2/fisiología , Animales , Colágeno/fisiología , Matriz Extracelular/fisiología , Proteínas de la Matriz Extracelular/fisiología , Fibronectinas/fisiología , Factores de Transcripción Forkhead/deficiencia , Factores de Transcripción Forkhead/genética , Regulación del Desarrollo de la Expresión Génica , Integrinas/fisiología , Mandíbula/embriología , Maxilar/embriología , Mesodermo/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Técnicas de Cultivo de Órganos , Fosforilación , Procesamiento Proteico-Postraduccional , Proteoglicanos/fisiología , Receptores de Factores de Crecimiento Transformadores beta/fisiología , Proteína Smad2/fisiología , Proteína smad3/fisiología , Lengua/anomalías , Lengua/embriología , Factor de Crecimiento Transformador beta2/biosíntesis , Factor de Crecimiento Transformador beta2/genética
4.
Gastroenterology ; 144(5): 1001-11, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23376422

RESUMEN

BACKGROUND & AIMS: The stem cell niche at the base of the intestinal crypts, as well as stemness and high clonogenicity in colon cancer cells, depend on Wnt signaling to ß-catenin. Fibroblasts modulate the Wnt pathway in normal and neoplastic epithelial cells via unclear mechanisms. We investigated how in intestinal fibroblasts the forkhead transcription factor Foxf2 controls Wnt signaling to affect numbers of stem cells and formation and growth of adenomas in mice. METHODS: We created mice with different copy numbers of Foxf2 by generating Foxf2(-/+) mice and a transgenic strain, Tg(FOXF2). Adenoma formation was investigated in Apc(Min/+) mice, stem cells were counted in mice with the Lgr5-enhanced green fluorescent protein knock-in allele, proliferation was measured by incorporation of bromodeoxyuridine, Foxf2 and Sfrp1 were localized by immunohistochemistry, and signaling pathways were analyzed by quantitative polymerase chain reaction and immunoblot assays. RESULTS: Epithelial ß-catenin was stabilized in Foxf2(-/+) mice, resulting in increased number and size of adenomas. Tg(FOXF2) mice, however, were partially resistant to intestinal neoplasia and developed fewer and smaller adenomas; Foxf2(-/+) mice developed 24-fold more tumors than Tg(FOXF2) mice. Epithelial cells of Foxf2(-/+) mice also had higher numbers of Lgr5(+) stem cells and greater amounts of crypt cell proliferation and expression of Myc (a target of Wnt signaling) than Tg(FOXF2) mice. Expression of Sfrp1, which encodes an extracellular inhibitor of Wnt, in fibroblasts increased with copy number of Foxf2. CONCLUSIONS: Foxf2 is a fibroblast factor that inhibits paracrine Wnt signaling and restricts the crypt stem cell niche in intestines of mice. Loss of Foxf2 promotes adenoma formation and growth.


Asunto(s)
Adenoma/genética , Neoplasias del Colon/genética , Fibroblastos/metabolismo , Factores de Transcripción Forkhead/genética , Regulación Neoplásica de la Expresión Génica , ARN Neoplásico/genética , Células Madre/patología , Adenoma/metabolismo , Adenoma/patología , Alelos , Animales , Recuento de Células , Proliferación Celular , Colon/metabolismo , Colon/patología , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Fibroblastos/patología , Factores de Transcripción Forkhead/biosíntesis , Immunoblotting , Inmunohistoquímica , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Ratones , Ratones Endogámicos C57BL , Microscopía Confocal , Neoplasias Experimentales , Reacción en Cadena de la Polimerasa , Células Madre/metabolismo , Células Tumorales Cultivadas , Proteínas Wnt/metabolismo , Vía de Señalización Wnt/genética
5.
Heliyon ; 10(4): e26218, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38420389

RESUMEN

The use of computer-based automated approaches and improvements in lung sound recording techniques have made lung sound-based diagnostics even better and devoid of subjectivity errors. Using a computer to evaluate lung sound features more thoroughly with the use of analyzing changes in lung sound behavior, recording measurements, suppressing the presence of noise contaminations, and graphical representations are all made possible by computer-based lung sound analysis. This paper starts with a discussion of the need for this research area, providing an overview of the field and the motivations behind it. Following that, it details the survey methodology used in this work. It presents a discussion on the elements of sound-based lung disease classification using machine learning algorithms. This includes commonly prior considered datasets, feature extraction techniques, pre-processing methods, artifact removal methods, lung-heart sound separation, deep learning algorithms, and wavelet transform of lung audio signals. The study introduces studies that review lung screening including a summary table of these references and discusses the literature gaps in the existing studies. It is concluded that the use of sound-based machine learning in the classification of respiratory diseases has promising results. While we believe this material will prove valuable to physicians and researchers exploring sound-signal-based machine learning, large-scale investigations remain essential to solidify the findings and foster wider adoption within the medical community.

6.
PLoS One ; 19(2): e0297376, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38422065

RESUMEN

Developing novel EV chargers is crucial for accelerating Electric Vehicle (EV) adoption, mitigating range anxiety, and fostering technological advancements that enhance charging efficiency and grid integration. These advancements address current challenges and contribute to a more sustainable and convenient future of electric mobility. This paper explores the performance dynamics of a solar-integrated charging system. It outlines a simulation study on harnessing solar energy as the primary Direct Current (DC) EV charging source. The approach incorporates an Energy Storage System (ESS) to address solar intermittencies and mitigate photovoltaic (PV) mismatch losses. Executed through MATLAB, the system integrates key components, including solar PV panels, the ESS, a DC charger, and an EV battery. The study finds that a change in solar irradiance from 400 W/m2 to 1000 W/m2 resulted in a substantial 47% increase in the output power of the solar PV system. Simultaneously, the ESS shows a 38% boost in output power under similar conditions, with the assessments conducted at a room temperature of 25°C. The results emphasize that optimal solar panel placement with higher irradiance levels is essential to leverage integrated solar energy EV chargers. The research also illuminates the positive correlation between elevated irradiance levels and the EV battery's State of Charge (SOC). This correlation underscores the efficiency gains achievable through enhanced solar power absorption, facilitating more effective and expedited EV charging.


Asunto(s)
Energía Solar , Humanos , Ansiedad , Trastornos de Ansiedad , Simulación por Computador , Sistemas de Computación
7.
Biochem Biophys Res Commun ; 437(2): 274-9, 2013 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-23811271

RESUMEN

The very low density lipoprotein receptor (VLDLr) is highly upregulated during hypoxia in mouse cardiomyocytes and in human and mouse ischemic hearts causing a detrimental lipid accumulation. To know how the gene is regulated is important for future studies. In this study, we have thoroughly mapped the 5'-flanking region of the mouse VLDLr promoter and show that the hypoxia-mediated increase in VLDLr expression is dependent on Hif-1α binding to a hypoxia responsive element (HRE) located at -162 to -158bp 5'of translation start. We show that classical HRE sites and the previously described PPARγ and Sp1 binding are not involved in the hypoxia-induced regulation of the VLDLr promoter. Using a chromatin immunoprecipitation (ChIP) assay, we show that Hif-1α specifically binds and activates the mouse VLDLr promoter at the previously described non-classical HRE in HL-1 cells. We also show that the same HRE is present and active in response to hypoxia in human cardiomyocytes, however at a different location (-812bp from translation start). These results conclude that in the hypoxic hearts of mice and men, the VLDLr gene is regulated by a direct binding of Hif-1α to the VLDLr promoter.


Asunto(s)
Hipoxia/fisiopatología , Receptores de LDL/fisiología , Animales , Sitios de Unión , Línea Celular , Cartilla de ADN , Ratones , PPAR gamma/metabolismo , Regiones Promotoras Genéticas , Receptores de LDL/genética , Factor de Transcripción Sp1/metabolismo
8.
Am J Med Genet A ; 161A(4): 764-70, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23444129

RESUMEN

Alveolar capillary dysplasia with misalignment of pulmonary veins (ACDMPV) is a congenital malformation that leads to severe pulmonary hypertension and respiratory failure. It has been associated with deletion of, or mutation in, FOXF1 on 16q24.1, a gene encoding a forkhead transcription factor expressed in the mesenchyme of the developing lung. Here we report on the identification of a pericentric inversion on chromosome 16 (p11.2q24.1) in a case of lethal ACDMPV with atrioventricular septal defect and duodenal atresia. Array-CGH indicated that the inversion is balanced, and FISH showed that the q-arm breakpoint occurs 134 ± 10 kb upstream (5'; centromeric) of FOXF1. This is suggestive of cis-regulatory elements located more than 130 kb 5' of FOXF1, and analysis of genome-wide data sets of chromatin modifications in two different cell types suggested that the FOXF1 regulatory domain covers more than 300 kb, and perhaps up to 433 kb, upstream of the gene, but only 3 kb downstream. The 588 kb gene-free region between FOXF1 and the next gene in the centromeric direction, IRF8, is highly conserved between species and divided into two distinct regulatory domains by an insulator element. Another putative insulator occurs just downstream of FOXF1. Our results further strengthen the association between FOXF1 and a spectrum of malformations that include ACDMPV, atrioventricular septal defects, and gastrointestinal atresia. Furthermore, the presented analysis aids in defining the critical genomic region for this syndrome.


Asunto(s)
Inversión Cromosómica , Factores de Transcripción Forkhead/genética , Síndrome de Circulación Fetal Persistente/genética , Síndrome de Circulación Fetal Persistente/patología , Autopsia , Cromosomas Humanos Par 16 , Hibridación Genómica Comparativa , Resultado Fatal , Femenino , Humanos , Hibridación Fluorescente in Situ , Recién Nacido , Factores Reguladores del Interferón/genética
9.
Nat Commun ; 13(1): 7162, 2022 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-36418331

RESUMEN

Cells and organisms require proper membrane composition to function and develop. Phospholipids are the major component of membranes and are primarily acquired through the diet. Given great variability in diet composition, cells must be able to deploy mechanisms that correct deviations from optimal membrane composition and properties. Here, using lipidomics and unbiased proteomics, we found that the embryonic lethality in mice lacking the fluidity regulators Adiponectin Receptors 1 and 2 (AdipoR1/2) is associated with aberrant high saturation of the membrane phospholipids. Using mouse embryonic fibroblasts (MEFs) derived from AdipoR1/2-KO embryos, human cell lines and the model organism C. elegans we found that, mechanistically, AdipoR1/2-derived sphingosine 1-phosphate (S1P) signals in parallel through S1PR3-SREBP1 and PPARγ to sustain the expression of the fatty acid desaturase SCD and maintain membrane properties. Thus, our work identifies an evolutionary conserved pathway by which cells and organisms achieve membrane homeostasis and adapt to a variable environment.


Asunto(s)
Caenorhabditis elegans , Receptores de Adiponectina , Humanos , Animales , Ratones , Receptores de Adiponectina/genética , Fibroblastos , Lisofosfolípidos , Homeostasis , Desarrollo Embrionario/genética
10.
Elife ; 102021 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-34609283

RESUMEN

Many diseases are linked to dysregulation of the striatum. Striatal function depends on neuronal compartmentation into striosomes and matrix. Striatal projection neurons are GABAergic medium spiny neurons (MSNs), subtyped by selective expression of receptors, neuropeptides, and other gene families. Neurogenesis of the striosome and matrix occurs in separate waves, but the factors regulating compartmentation and neuronal differentiation are largely unidentified. We performed RNA- and ATAC-seq on sorted striosome and matrix cells at postnatal day 3, using the Nr4a1-EGFP striosome reporter mouse. Focusing on the striosome, we validated the localization and/or role of Irx1, Foxf2, Olig2, and Stat1/2 in the developing striosome and the in vivo enhancer function of a striosome-specific open chromatin region 4.4 Kb downstream of Olig2. These data provide novel tools to dissect and manipulate the networks regulating MSN compartmentation and differentiation, including in human iPSC-derived striatal neurons for disease modeling and drug discovery.


Asunto(s)
Diferenciación Celular/genética , Neostriado/fisiología , Neuronas/fisiología , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Animales , Diferenciación Celular/fisiología , Células Cultivadas , Femenino , Humanos , Ratones , Neostriado/patología
11.
Dev Cell ; 34(1): 19-32, 2015 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-26120030

RESUMEN

Pericytes are critical for cerebrovascular maturation and development of the blood-brain barrier (BBB), but their role in maintenance of the adult BBB, and how CNS pericytes differ from those of other tissues, is less well understood. We show that the forkhead transcription factor Foxf2 is specifically expressed in pericytes of the brain and that Foxf2(-/-) embryos develop intracranial hemorrhage, perivascular edema, thinning of the vascular basal lamina, an increase of luminal endothelial caveolae, and a leaky BBB. Foxf2(-/-) brain pericytes were more numerous, proliferated faster, and expressed significantly less Pdgfrß. Tgfß-Smad2/3 signaling was attenuated, whereas phosphorylation of Smad1/5 and p38 were enhanced. Tgfß pathway components, including Tgfß2, Tgfßr2, Alk5, and integrins αVß8, were reduced. Foxf2 inactivation in adults resulted in BBB breakdown, endothelial thickening, and increased trans-endothelial vesicular transport. On the basis of these results, FOXF2 emerges as an interesting candidate locus for stroke susceptibility in humans.


Asunto(s)
Barrera Hematoencefálica/citología , Barrera Hematoencefálica/metabolismo , Diferenciación Celular/fisiología , Factores de Transcripción Forkhead/metabolismo , Pericitos/citología , Animales , Transporte Biológico/fisiología , Encéfalo/citología , Encéfalo/metabolismo , Células Endoteliales/metabolismo , Células Endoteliales/ultraestructura , Ratones , Pericitos/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Receptor Tipo I de Factor de Crecimiento Transformador beta , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Factor de Crecimiento Transformador beta/metabolismo
12.
Biotechniques ; 55(1): 42-4, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23834385

RESUMEN

Current protocols for separating adult intestinal epithelial cells from the underlying muscular and mesenchymal tissues typically involve extended incubations, harsh mechanical treatment, and exposure to either proteases or chelating agents. The drawbacks of these approaches include fragmentation, contamination with other cell types, reduced viability, and under-representation of crypt cells. Here we describe a gentle procedure that allows harvesting of pure, fully viable sheets of murine intestinal epithelium, with intact crypts and villi, without enzymes or EDTA. The mesenchyme retains intact villus core projections, is virtually free from epithelial cells, and can be cultured in vitro.


Asunto(s)
Técnicas Histológicas/instrumentación , Técnicas Histológicas/métodos , Mucosa Intestinal/anatomía & histología , Mucosa Intestinal/fisiología , Mesodermo/anatomía & histología , Mesodermo/fisiología , Animales , Ratones , Ratones Transgénicos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA