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1.
Front Neurol ; 15: 1366776, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38601336

RESUMO

An increasing number of gene mutations associated with epilepsy have been identified, some linked to gray matter heterotopia-a common cause of drug-resistant epilepsy. Current research suggests that gene mutation-associated epilepsy should not be considered a contraindication for surgery in epilepsy patients. At present, stereoelectroencephalography-guided radiofrequency thermocoagulation is an important method to treat periventricular nodular heterotopia-associated drug-resistant epilepsy. We present a case of drug-resistant epilepsy, accompanied by periventricular nodular heterotopia and a heterozygous mutation of the RELN gene, successfully treated with radiofrequency thermocoagulation, resulting in a favorable outcome.

2.
Nat Mater ; 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605194

RESUMO

Magnetic skyrmions are promising as next-generation information units. Their antiparticle-the antiskyrmion-has also been discovered in chiral magnets. Here we experimentally demonstrate antiskyrmion sliding in response to a pulsed electric current at room temperature without the requirement of an external magnetic field. This is realized by embedding antiskyrmions in helical stripe domains, which naturally provide one-dimensional straight tracks along which antiskyrmion sliding can be easily launched with low current density and without transverse deflection from the antiskyrmion Hall effect. The higher mobility of the antiskyrmions in the background of helical stripes in contrast to the typical ferromagnetic state is a result of intrinsic material parameters and elastic energy of the stripe domain, thereby smearing out the random pinning potential, as supported by micromagnetic simulations. The demonstration and comprehensive understanding of antiskyrmion movement along naturally straight tracks offers a new perspective for (anti)skyrmion application in spintronics.

3.
Nat Commun ; 15(1): 955, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38302463

RESUMO

Ageing exhibits common and distinct features in various tissues, making it critical to decipher the tissue-specific ageing mechanisms. MiRNAs are essential regulators in ageing and are recently highlighted as a class of intercellular messengers. However, little is known about the tissue-specific transcriptomic changes of miRNAs during ageing. C. elegans is a well-established model organism in ageing research. Here, we profile the age-dependent miRNAomic changes in five isolated worm tissues. Besides the diverse ageing-regulated miRNA expression across tissues, we discover numerous miRNAs in the tissues without their transcription. We further profile miRNAs in the extracellular vesicles and find that worm miRNAs undergo inter-tissue trafficking via these vesicles in an age-dependent manner. Using these datasets, we uncover the interaction between body wall muscle-derived mir-1 and DAF-16/FOXO in the intestine, suggesting mir-1 as a messenger in inter-tissue signalling. Taken together, we systematically investigate worm miRNAs in the somatic tissues and extracellular vesicles during ageing, providing a valuable resource to study tissue-autonomous and nonautonomous functions of miRNAs in ageing.


Assuntos
Proteínas de Caenorhabditis elegans , MicroRNAs , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Envelhecimento/genética , Intestinos , MicroRNAs/metabolismo , Longevidade/genética
4.
Environ Pollut ; 342: 123104, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38070645

RESUMO

Reservoirs play important roles in the drinking water supply for urban residents, agricultural water provision, and the maintenance of ecosystem health. Satellite optical remote sensing of water quality variables in medium and micro-sized inland waters under oligotrophic and mesotrophic status is challenging in terms of the spatio-temporal resolution, weather conditions and frequent nutrient status changes in reservoirs, etc., especially when quantifying non-optically active components (non-OACs). This study was based on the surface reflectance products of unmanned aerial vehicle (UAV) multispectral images, Sentinel-2B Multispectral instrument (MSI) images and Landsat 7 Enhanced Thematic Mapper Plus (ETM+) by utilizing fuzzy C-means (FCM) clustering algorithm was combined with band combination (BC) model to construct the FCM-BC empirical model, and used mixed density network (MDN), extreme gradient boosting (XGBoost), deep neural network (DNN) and support vector regression (SVR) machine learning (ML) models to invert 12 kinds of optically active components (OACs) and non-OACs. Compared with the unclustered BC (UC) model, the mean coefficient of determination (MR) of the FCM-BC models was improved by at least 46.9%. MDN model showed best accuracy (R2 in the range of 0.60-0.98) and stability (R2 decreased by up to 13.2%). The accuracy of UAV was relatively higher in both empirical methods and machine learning methods. Additionally, the spatio-temporal distribution maps of four water quality variables were mapped based on the MDN model and UAV images, all platforms showed good consistency. An inversion strategy of water quality variables in various monitoring frequencies and weather conditions were proposed finally. The purpose of introducing the UAV platform was to cooperate with the satellite to improve the monitoring response ability of OACs and non-OACs in small and micro-sized oligotrophic and mesotrophic water bodies.


Assuntos
Tecnologia de Sensoriamento Remoto , Qualidade da Água , Ecossistema , Abastecimento de Água , China
5.
Entropy (Basel) ; 25(10)2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37895578

RESUMO

For this study, we investigated efficient strategies for the recovery of individual links in power grids governed by the direct current (DC) power flow model, under random link failures. Our primary objective was to explore the efficacy of recovering failed links based solely on topological network metrics. In total, we considered 13 recovery strategies, which encompassed 2 strategies based on link centrality values (link betweenness and link flow betweenness), 8 strategies based on the products of node centrality values at link endpoints (degree, eigenvector, weighted eigenvector, closeness, electrical closeness, weighted electrical closeness, zeta vector, and weighted zeta vector), and 2 heuristic strategies (greedy recovery and two-step greedy recovery), in addition to the random recovery strategy. To evaluate the performance of these proposed strategies, we conducted simulations on three distinct power systems: the IEEE 30, IEEE 39, and IEEE 118 systems. Our findings revealed several key insights: Firstly, there were notable variations in the performance of the recovery strategies based on topological network metrics across different power systems. Secondly, all such strategies exhibited inferior performance when compared to the heuristic recovery strategies. Thirdly, the two-step greedy recovery strategy consistently outperformed the others, with the greedy recovery strategy ranking second. Based on our results, we conclude that relying solely on a single metric for the development of a recovery strategy is insufficient when restoring power grids following link failures. By comparison, recovery strategies employing greedy algorithms prove to be more effective choices.

6.
Mol Cancer Ther ; 22(12): 1479-1492, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37710057

RESUMO

Aberrant activation of the FGF19-FGFR4 signaling pathway plays an essential role in the tumorigenesis of hepatocellular carcinoma (HCC). As such, FGFR4 inhibition has emerged as a novel therapeutic option for the treatment of HCC and has shown preliminary efficacy in recent clinical trials for patients exhibiting aberrant FGF19 expression. Resistance to kinase inhibitors is common in oncology, presenting a major challenge in the clinical treatment process. Hence, we investigated the potential mechanisms mediating and causing resistance to FGFR4 inhibition in HCC. Upon the successful establishment of a battery of cellular models developing resistance to FGFR4 inhibitors, we have identified the activation of EGFR, MAPK, and AKT signaling as the primary mechanisms mediating the acquired resistance. Combination of inhibitors against EGFR or its downstream components restored sensitivity to FGFR4 inhibitors. In parental HCC cell lines, EGF treatment also resulted in resistance to FGFR4 inhibitors. This resistance was effectively reverted by inhibitors of the EGFR signaling pathway, suggesting that EGFR activation is a potential cause of intrinsic resistance. We further confirmed the above findings in vivo in mouse xenograft tumor models. Genomic analysis of patient samples from The Cancer Genome Atlas confirmed that a segment of patients with HCC harboring FGF19 overexpression indeed exhibited increased activation of EGFR signaling. These findings conclusively indicate that both induced and innate activation of EGFR could mediate resistance to FGFR4 inhibition, suggesting that dual blockade of EGFR and FGFR4 may be a promising future therapeutic strategy for the treatment of FGF19-FGFR4 altered HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Animais , Camundongos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Fatores de Crescimento de Fibroblastos/genética , Transdução de Sinais , Receptores ErbB/metabolismo , Linhagem Celular Tumoral , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/genética
7.
Cell Mol Neurobiol ; 43(2): 639-647, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35438385

RESUMO

Major facilitator superfamily-domain containing 2a (Mfsd2a) is selectively expressed in vascular endotheliocytes and plays a crucial role in maintaining the integrity of the blood‒brain barrier and the transport of docosahexaenoic acid. It is currently recognized as the only molecule that inhibits endocytosis mediated by caveolae in brain endothelial cells. Mfsd2a gene knockout leads to an increase in the permeability of the blood-brain barrier from embryonic stages to adulthood while maintaining the normal pattern of the vascular network. In Mfsd2a knockout mice, the docosahexaenoic acid content is significantly reduced and associated with neuron loss, resulting in microcephaly and cognitive impairment. Based on the role of Mfsd2a in the central nervous system, it has been preliminarily suggested as a potential therapeutic target for drug delivery to the central nervous system. This paper reviews the current progress in Mfsd2a research and summarizes the physiological functions of Mfsd2a in the central nervous system and its role in the occurrence and development of a variety of neurological diseases.


Assuntos
Ácidos Docosa-Hexaenoicos , Simportadores , Animais , Camundongos , Células Endoteliais/metabolismo , Simportadores/metabolismo , Encéfalo/metabolismo , Barreira Hematoencefálica/metabolismo
8.
EMBO J ; 41(8): e109633, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35253240

RESUMO

Ageing is a complex process with common and distinct features across tissues. Unveiling the underlying processes driving ageing in individual tissues is indispensable to decipher the mechanisms of organismal longevity. Caenorhabditis elegans is a well-established model organism that has spearheaded ageing research with the discovery of numerous genetic pathways controlling its lifespan. However, it remains challenging to dissect the ageing of worm tissues due to the limited description of tissue pathology and access to tissue-specific molecular changes during ageing. In this study, we isolated cells from five major tissues in young and old worms and profiled the age-induced transcriptomic changes within these tissues. We observed a striking diversity of ageing across tissues and identified different sets of longevity regulators therein. In addition, we found novel tissue-specific factors, including irx-1 and myrf-2, which control the integrity of the intestinal barrier and sarcomere structure during ageing respectively. This study demonstrates the complexity of ageing across worm tissues and highlights the power of tissue-specific transcriptomic profiling during ageing, which can serve as a resource to the field.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Envelhecimento/genética , Envelhecimento/metabolismo , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Longevidade/genética , Transcriptoma
9.
Reprod Toxicol ; 104: 1-7, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34166781

RESUMO

Mesenchymal cell proliferation is critical for the growth of the palate shelf. All-trans retinoic acid (atRA), as well as pathways associated with TGF-ß/Smad signaling, play crucial roles in the proliferation of mouse embryonic palate mesenchymal (MEPM) cells. We have found that MEPM-cell proliferation was regulated by atRA and exogenous TGF-ß3 could significantly antagonize the atRA-mediated suppression of MEPM cell proliferation, which is closely associated with the regulation of TGF-ß/Smad signaling pathway. The long non-coding RNA (lncRNA) MEG3 has been reported to activate TGF-ß/Smad signaling, thereby regulating cellular proliferation, differentiation, and related processes. Here, we found that Meg3 expression increased significantly in atRA-treated MEPM cells while TGF-ß3 treatment markedly inhibited Meg3 expression and antagonized the effect of atRA on Meg3. Moreover, Smad2 was found to interact directly with Meg3, and atRA treatment significantly enriched Meg3 in Smad2-immunoprecipitated samples. After Meg3 deletion, the effects of atRA on the proliferation of MEPM cells and TGF-ß3-dependent protein expression were lost. Hence, we speculate that Meg3 has a role in the RA-induced suppression of MEPM cell proliferation by targeting Smad2 and thereby mediating TGF-ß/Smad signaling inhibition.


Assuntos
Proliferação de Células/fisiologia , RNA Longo não Codificante , Tretinoína/toxicidade , Animais , Células Cultivadas , Fissura Palatina , Regulação da Expressão Gênica no Desenvolvimento , Células-Tronco Mesenquimais , Camundongos , Palato , Fosforilação , Transdução de Sinais , Fator de Crescimento Transformador beta3
10.
Exp Biol Med (Maywood) ; 246(18): 2019-2028, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34053232

RESUMO

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is a persistent organic pollutant that is strongly associated with a number of human diseases and birth defects, including cleft palate. Transforming growth factor (TGF) plays a significant role during mammalian palatogenesis. However, the epigenetic mechanism of transforming growth factors in the process of TCDD-induced cleft palate is unclear. The purpose of this research was to investigate the relationship and potential mechanism between TGF-ß2/3 promoter DNA methylation and Smad signaling during TCDD-induced cleft palate. Pregnant C57BL/6N mice were exposed to 64 µg/kg TCDD on gestational day 10 (GD10) to establish the cleft palate model and palatal tissues of embryos were collected on GD13, GD14, and GD15 for subsequent experiments. TGF-ß2/3 mRNA expression, TGF-ß2/3 promoter methylation, and Smad signaling molecules expression were assessed in the palate of the two groups. The results showed that the incidence of cleft palate was 94.7% in the TCDD-treated group whereas no cleft palate was found in the control group. TCDD-treated group altered specific CpG sites of TGF-ß2/3 promoter methylation. Compared to the control group, the proliferation of mouse embryonic palate mesenchymal stromal cells (MEPM), the expressions of TGF-ß2/3, p-Smad2, and Smad4 were all reduced, while the expression of Smad7 was significantly increased in the atAR group. Smad signaling was downregulated by TCDD. Therefore, we suggest that TGF-ß2/3 promoter methylation and Smad signaling may be involved in TCDD-induced cleft palate formation in fetal mice.


Assuntos
Proteínas Reguladoras de Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Metilação de DNA/efeitos dos fármacos , Proteínas Mitocondriais/efeitos dos fármacos , Proteínas Mitocondriais/metabolismo , Dibenzodioxinas Policloradas/farmacologia , Animais , Regulação para Baixo , Camundongos Endogâmicos C57BL , Palato/efeitos dos fármacos , Dibenzodioxinas Policloradas/metabolismo , Regiões Promotoras Genéticas/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta2/genética , Fator de Crescimento Transformador beta2/metabolismo
11.
Sensors (Basel) ; 21(9)2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33924812

RESUMO

Digital microfluidics (DMF) devices enable precise manipulation of small liquid volumes in point-of-care testing. A printed circuit board (PCB) substrate is commonly utilized to build DMF devices. However, inkjet printing can be used to fabricate DMF circuits, providing a less expensive alternative to PCB-based DMF designs while enabling more rapid design iteration cycles. We demonstrate the cleanroom-free fabrication process of a low-cost inkjet-printed DMF circuit. We compare Kapton and polymethyl methacrylate (PMMA) as dielectric coatings by measuring the minimal droplet actuation voltage for a range of actuation frequencies. A minimum actuation voltage of 5.6 V was required for droplet movement with the PMMA layer thickness of 0.2 µm and a hydrophobic layer of 0.17 µm. Significant issues with PMMA dielectric breakdown were observed at actuation voltages above 10 V. In comparison, devices that utilized Kapton were found to be more robust, even at an actuation voltage up to 100 V.


Assuntos
Dispositivos Lab-On-A-Chip , Microfluídica
12.
Toxicol Appl Pharmacol ; 419: 115517, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33812962

RESUMO

Cleft palate (CP) is a common birth defect with a high incidence of occurrence in humans. The 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD) is a highly toxic halogenated aromatic hydrocarbon, with a strong CP effect on mice. Increasing recent evidences have shown that long-noncoding RNAs (lncRNAs) play an important role in several diseases, including CP. However, there is a paucity of studies on the role of lncRNA MEG3 in the occurrence and development of TCDD-induced CP. In this study, the relationship between MEG3 and the proliferation of palatal mesenchymal cells and the underlying molecular mechanism were studied by establishing fetal CP with TCDD (64 µg/kg) in C57BL/6N mice. The results revealed that MEG3 was highly expressed during the critical period of CP formation and that the fetal mesenchymal proliferation was significantly inhibited at certain critical periods in the mice receiving TCDD. In addition, we noted a possibility of a crosstalk between MEG3 and the TGF-ß/Smad pathway, such that the inhibition of the TGF-ß/Smad pathway was induced by TCDD. Cumulatively, our study suggests that TCDD-induced CP may be caused by MEG3 inhibition of the proliferation of palatal mesenchymal cells involving the TGFß/Smad pathway, which may provide a novel perspective to understand the pathogenesis of CP.


Assuntos
Proliferação de Células , Fissura Palatina/metabolismo , Células-Tronco Mesenquimais/metabolismo , Palato Duro/metabolismo , RNA Longo não Codificante/metabolismo , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Fissura Palatina/induzido quimicamente , Fissura Palatina/genética , Fissura Palatina/patologia , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Idade Gestacional , Células-Tronco Mesenquimais/patologia , Camundongos Endogâmicos C57BL , Palato Duro/anormalidades , Fosforilação , Dibenzodioxinas Policloradas , Gravidez , RNA Longo não Codificante/genética , Receptor do Fator de Crescimento Transformador beta Tipo I/genética , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta1/genética
13.
Toxicol Lett ; 341: 51-58, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33493612

RESUMO

Palatal mesenchymal cell proliferation is essential to the process of palatogenesis, and the proliferation of mouse embryonic palate mesenchymal (MEPM) cells is impacted by both all-trans retinoic acid (atRA) and the TGF-ß/Smad signaling pathway. The long non-coding RNA (lncRNA) MEG3 has been shown to activate TGF-ß/Smad signaling and to thereby regulate cell proliferation, differentiation, and related processes. Herein, we found that atRA treatment (100 mg/kg) promoted Meg3 upregulation in MEPM cells, and that such upregulation was linked to the suppression of MEPM cell proliferation in the context of secondary palate fusion on gestational day (GD) 13 and 14. Moreover, the demethylation of specific CpG sites within the lncRNA Meg3 promoter was detected in atRA-treated MEPM cells, likely explaining the observed upregulation of this lncRNA. Smad signaling was also suppressed by atRA treatment in these cells, and RNA immunoprecipitation analyses revealed that Smad2 can directly interact with Meg3 in MEPM cells following atRA treatment. Therefore, we propose a model wherein Meg3 is involved in the suppression of MEPM cell proliferation, functioning at least in part via interacting with the Smad2 protein and thereby suppressing Smad signaling in the context of atRA-induced cleft palate.


Assuntos
Fissura Palatina/induzido quimicamente , RNA Longo não Codificante/metabolismo , Proteínas Smad/metabolismo , Tretinoína/efeitos adversos , Animais , Fissura Palatina/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Ceratolíticos/toxicidade , Camundongos , Palato/efeitos dos fármacos , Palato/embriologia , Palato/patologia , Gravidez , RNA Longo não Codificante/genética , Proteínas Smad/genética
14.
Front Public Health ; 8: 498056, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33282807

RESUMO

The continually increasing number of patients with type 2 diabetes is a worldwide health problem, and the incidence of microvascular complications is closely related to type 2 diabetes. Structural brain abnormalities are considered an important pathway through which type 2 diabetes causes brain diseases. In fact, there is considerable evidence that type 2 diabetes is associated with an increased risk of structural brain abnormalities such as lacunar infarcts (LIs), white matter hyperintensities (WMHs), and brain atrophy. WMHs are a common cerebral small-vessel disease in elderly adults, and it is characterized histologically by demyelination, loss of oligodendrocytes, and vacuolization as a result of small-vessel ischemia in the white matter. An increasing number of studies have found that diabetes is closely related to WMHs. However, the exact mechanism by which type 2 diabetes causes WMHs is not fully understood. This article reviews the mechanisms of type 2 diabetes-related WMHs to better understand the disease and provide help for better clinical treatment.


Assuntos
Doenças de Pequenos Vasos Cerebrais , Diabetes Mellitus Tipo 2 , Leucoaraiose , Substância Branca , Adulto , Idoso , Diabetes Mellitus Tipo 2/complicações , Humanos , Imageamento por Ressonância Magnética , Substância Branca/diagnóstico por imagem
15.
Toxicology ; 438: 152444, 2020 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-32283119

RESUMO

As a common birth defect, Cleft palate can be caused by the disturbance during the developmental process of the palatal shelves. The 2,3,7,8-tetrachlorodibenzo- p-dioxin (TCDD) is a well-known environmental teratogenic agent for cleft palate and Aryl hydrocarbon receptor (AhR) pathway can be activated by dioxins. Oct4 as a pluripotent stem cell transcription factor is also involved in the process of embryonic development. The AHR and retinoid receptors have cross-talk at CYP1A1 (cytochrome P450, family 1, subfamily A, polypeptide 1) promoter. There are also bidirectional talk between AhR and Oct4. In this study, we used C57/BL6 N mice and TCDD (64 µg/Kg body weight) to establish a model of fetal cleft palate to observe the effects of dioxin on fetal mesenchymal proliferation and apoptosis, and explore the role of Oct4 in inducing cleft palate. The results showed that dioxin inhibited mesenchymal proliferation and promoted apoptosis. In addition, dioxin inhibited Oct4 expression, and preliminary data suggest that hypermethylation of the Oct4 promoter may be a putative mechanism, suggesting that TCDD might induce cleft palate by inhibiting the proliferation of palatal mesenchymal cells mediated by Oct4.


Assuntos
Proliferação de Células , Fissura Palatina/metabolismo , Mesoderma/metabolismo , Fator 3 de Transcrição de Octâmero/metabolismo , Palato/metabolismo , Dibenzodioxinas Policloradas , Animais , Apoptose , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fissura Palatina/induzido quimicamente , Fissura Palatina/patologia , Metilação de DNA , Modelos Animais de Doenças , Feminino , Masculino , Mesoderma/anormalidades , Camundongos Endogâmicos C57BL , Fator 3 de Transcrição de Octâmero/genética , Palato/anormalidades , Gravidez , Regiões Promotoras Genéticas , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Transdução de Sinais
16.
Toxicology ; 431: 152353, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887333

RESUMO

Exposure to environmental toxicant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) causes cleft palate at high rates, but little is known about the underlying biological mechanisms. In the present study, we cultured osteoblasts from human fetal palate mesenchymal cells (hFPMCs) to explore the effects of TCDD on osteogenic differentiation. The results showed that TCDD significantly decreased cell proliferation, alkaline phosphatase (ALP) activity and calcium deposition. RNA analyses and protein detection demonstrated that TCDD downregulated a wide array of pro-osteogenic biomarkers. Further investigation of the underlying molecular mechanisms revealed that exposure to TCDD activated aryl hydrocarbon receptor (AhR) signaling and inhibited BMP-2/TGF-ß1/Smad pathway molecules. The inactivation of AhR signaling using CRISPR/Cas9-mediated AhR deletion or by genetic siRNA knockdown significantly blocked the effects induced by TCDD, suggesting a critical role of AhR activation in the TCDD-mediated inhibition of hFPMC osteogenic differentiation. The cotreatment with TGF-ß1 or BMP-2 and TCDD significantly relieved the activation of AhR and rescued the impairment of osteogenesis caused by TCDD. Taken together, our findings indicated that TCDD inhibited the osteogenic differentiation of hFPMCs via crosstalk between AhR and BMP-2/TGF-ß1/Smad signaling pathway.


Assuntos
Poluentes Ambientais/toxicidade , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Palato/citologia , Dibenzodioxinas Policloradas/toxicidade , Transdução de Sinais/efeitos dos fármacos , Fosfatase Alcalina/metabolismo , Proteína Morfogenética Óssea 2/efeitos dos fármacos , Cálcio/metabolismo , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Humanos , Palato/efeitos dos fármacos , Palato/embriologia , Gravidez , Receptores de Hidrocarboneto Arílico/efeitos dos fármacos , Proteínas Smad/efeitos dos fármacos , Fator de Crescimento Transformador beta/efeitos dos fármacos
17.
Nat Commun ; 10(1): 4827, 2019 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-31645592

RESUMO

Macroautophagy, a key player in protein quality control, is proposed to be systematically impaired in distinct tissues and causes coordinated disruption of protein homeostasis and ageing throughout the body. Although tissue-specific changes in autophagy and ageing have been extensively explored, the mechanism underlying the inter-tissue regulation of autophagy with ageing is poorly understood. Here, we show that a secreted microRNA, mir-83/miR-29, controls the age-related decrease in macroautophagy across tissues in Caenorhabditis elegans. Upregulated in the intestine by hsf-1/HSF1 with age, mir-83 is transported across tissues potentially via extracellular vesicles and disrupts macroautophagy by suppressing CUP-5/MCOLN, a vital autophagy regulator, autonomously in the intestine as well as non-autonomously in body wall muscle. Mutating mir-83 thereby enhances macroautophagy in different tissues, promoting protein homeostasis and longevity. These findings thus identify a microRNA-based mechanism to coordinate the decreasing macroautophagy in various tissues with age.


Assuntos
Envelhecimento/genética , Caenorhabditis elegans/genética , Macroautofagia/genética , MicroRNAs/genética , Animais , Autofagia/genética , Proteínas de Caenorhabditis elegans/metabolismo , Vesículas Extracelulares/metabolismo , Mucosa Intestinal/metabolismo , Intestinos , Proteínas de Membrana/metabolismo , MicroRNAs/metabolismo , Músculos/metabolismo , Fatores de Transcrição/metabolismo
18.
EMBO Rep ; 20(5)2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30872315

RESUMO

Dietary restriction (DR) is known to have a potent and conserved longevity effect, yet its underlying molecular mechanisms remain elusive. DR modulates signaling pathways in response to nutrient status, a process that also regulates animal development. Here, we show that the suppression of Wnt signaling, a key pathway controlling development, is required for DR-induced longevity in Caenorhabditis elegans We find that DR induces the expression of mir-235, which inhibits cwn-1/WNT4 expression by binding to the 3'-UTR The "switch-on" of mir-235 by DR occurs at the onset of adulthood, thereby minimizing potential disruptions in development. Our results therefore implicate that DR controls the adult lifespan by using a temporal microRNA switch to modulate Wnt signaling.


Assuntos
Longevidade/genética , MicroRNAs/genética , Proteínas Wnt/genética , Via de Sinalização Wnt/genética , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Restrição Calórica/métodos
19.
J Drug Target ; 27(8): 866-875, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30601069

RESUMO

Recently, a wealth of information has emerged connecting the activation of the NLRP3 (NOD-like receptor family pyrin domain-containing 3) inflammasome to stroke pathogenesis, although the exact influence of the NLRP3 inflammasome on stroke is still in the stage of preliminary study and is awaiting further confirmation. In this paper, we will review the structure, assembly and activation of the NLRP3 inflammasome and its expression in the neurovascular units and will speculate on its possible roles in neurovascular injury post-stroke. Evidence on this topic suggests that targeting NLRP3-mediated inflammation at multiple levels may provide a new therapeutic strategy to prevent the deterioration of neurovascular units after stroke. However, many aspects of the biological link between the NLRP3 inflammasome and stroke remain ill-defined or even completely unknown. As fresh insights come to light regarding the NLRP3 inflammasome, the opportunities to develop new therapeutic strategies for stroke patients are expected to improve accordingly.


Assuntos
Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Acidente Vascular Cerebral/metabolismo , Animais , Proteínas de Transporte/metabolismo , Humanos , Mediadores da Inflamação/metabolismo
20.
Medicine (Baltimore) ; 97(50): e13476, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30558002

RESUMO

RATIONALE: Multifocal cerebral hemorrhage refers to the cerebral hemorrhage in 2 or more lesions at the same time or 48 h in the brain caused by various causes, which has an acute onset, high mortality rate, and poor clinical treatment effect. Subarachnoid hemorrhage (SAH) is caused by the direct flow of blood into the subarachnoid cavity due to the rupture of the diseased vessels at the base or surface of the brain. Cerebral venous sinus thrombosis (CVST) affects approximately 5 people per million and accounts for approximately 1% of all stroke events. CVST with both SAH and multifocal intracerebral hemorrhage (ICH) as the first presentation is extremely rare. PATIENT CONCERNS: A 57-year-old woman presented with dizziness, nausea, and vomiting. DIAGNOSIS: Neuroimaging confirmed a diagnosis of CVST. INTERVENTIONS: The patient was treated with dehydration, scavenging free radicals, and nerve protection therapy. OUTCOMES: After 4 weeks of systematic treatment, the patient resumed independent daily activities and was discharged with only slight non-fluent aphasia. She did not exhibit recurrent thrombosis at an 18-month follow-up point. MAIN LESSONS: The usual treatment for sinus thrombosis is anticoagulation or local thrombolysis. Systemic anticoagulation is the first-line treatment for CVST, even in patients with cerebral hemorrhage or SAH. The present patient's hemorrhage clearly contraindicated heparin; therefore, no anticoagulants or thrombolytic agents were administered during the 4-week hospitalization. We discuss issues for consideration in similar cases and provide an example of determining an individualized approach to treatment.


Assuntos
Hemorragia Cerebral/etiologia , Trombose dos Seios Intracranianos/complicações , Hemorragia Subaracnóidea/etiologia , Feminino , Humanos , Pessoa de Meia-Idade
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