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1.
Dev Cell ; 58(1): 3-17.e8, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36516856

RESUMO

In many developing tissues, the patterns of gene expression that assign cell fate are organized by graded secreted signals. Cis-regulatory elements (CREs) interpret these signals to control gene expression, but how this is accomplished remains poorly understood. In the neural tube, a gradient of the morphogen sonic hedgehog (Shh) patterns neural progenitors. We identify two distinct ways in which CREs translate graded Shh into differential gene expression in mouse neural progenitors. In most progenitors, a common set of CREs control gene activity by integrating cell-type-specific inputs. By contrast, the most ventral progenitors use a unique set of CREs, established by the pioneer factor FOXA2. This parallels the role of FOXA2 in endoderm, where FOXA2 binds some of the same sites. Together, the data identify distinct cis-regulatory strategies for the interpretation of morphogen signaling and raise the possibility of an evolutionarily conserved role for FOXA2 across tissues.


Assuntos
Proteínas Hedgehog , Tubo Neural , Animais , Camundongos , Tubo Neural/metabolismo , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Diferenciação Celular , Sistema Nervoso/metabolismo , Transdução de Sinais/genética , Regulação da Expressão Gênica no Desenvolvimento
2.
PLoS Biol ; 19(11): e3001450, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34767545

RESUMO

The molecular mechanisms that produce the full array of neuronal subtypes in the vertebrate nervous system are incompletely understood. Here, we provide evidence of a global temporal patterning program comprising sets of transcription factors that stratifies neurons based on the developmental time at which they are generated. This transcriptional code acts throughout the central nervous system, in parallel to spatial patterning, thereby increasing the diversity of neurons generated along the neuraxis. We further demonstrate that this temporal program operates in stem cell-derived neurons and is under the control of the TGFß signaling pathway. Targeted perturbation of components of the temporal program, Nfia and Nfib, reveals their functional requirement for the generation of late-born neuronal subtypes. Together, our results provide evidence for the existence of a previously unappreciated global temporal transcriptional program of neuronal subtype identity and suggest that the integration of spatial and temporal patterning mechanisms diversifies and organizes neuronal subtypes in the vertebrate nervous system.


Assuntos
Padronização Corporal/genética , Sistema Nervoso Central/metabolismo , Transcrição Gênica , Animais , Encéfalo/citologia , Regulação da Expressão Gênica no Desenvolvimento , Camundongos , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Neurogênese/fisiologia , Neurônios/fisiologia , Retina/citologia , Transdução de Sinais , Medula Espinal/citologia , Fatores de Tempo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta/metabolismo
3.
Nanomedicine ; 14(7): 2179-2189, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30048816

RESUMO

Nanotransducer-mediated photothermal therapy (PTT) has emerged as an attractive therapy modality against cancer, but its efficacy is often limited by the amount of nanoparticles delivered to tumors. Previous studies showed a vasculature modulation treatment, which dilates or prunes tumor blood vessels, may enhance tumor uptake of nanoparticles. However, exploiting these approaches for improved PTT has seldom been studied. In this study, we investigated the impact of mild hyperthermia or anti-angiogenesis therapy on PTT. Briefly, we gave tumor-bearing balb/c mice low doses of sunitinib or submerged tumors in a 42 °C water bath. Next, we injected PEGylated reduced graphene oxide (RGO-PEG) and irradiated the tumors to induce PTT. We then followed up the treatment with multi-parameter MRI. Contrary to expectation, both vessel modulation strategies led to diminished PTT efficacy. Our results show that vessel modulation does not warrant improved PTT, and should be carefully gauged when used in combination with PTT.


Assuntos
Inibidores da Angiogênese/administração & dosagem , Neoplasias da Mama/terapia , Hipertermia Induzida , Imageamento por Ressonância Magnética/métodos , Neovascularização Patológica/terapia , Fototerapia , Sunitinibe/administração & dosagem , Inibidores da Angiogênese/química , Inibidores da Angiogênese/farmacologia , Animais , Apoptose , Neoplasias da Mama/irrigação sanguínea , Neoplasias da Mama/patologia , Proliferação de Células , Terapia Combinada , Feminino , Grafite/química , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/administração & dosagem , Nanopartículas/química , Neovascularização Patológica/patologia , Sunitinibe/química , Sunitinibe/farmacologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
4.
J Nutr ; 146(11): 2325-2333, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27683874

RESUMO

BACKGROUND: Cocoa flavanols may improve cardiometabolic health. Evidence from small short-term randomized clinical trials (RCTs) remains inconsistent, and large long-term RCTs testing the efficacy of cocoa flavanols are still lacking. OBJECTIVE: We performed a systematic review and meta-analysis of RCTs to quantify the effect of cocoa flavanol intake on cardiometabolic biomarkers. METHODS: We searched PubMed, Web of Science, and the Cochrane Library for RCTs that evaluated the effects of cocoa flavanols on biomarkers relevant to vascular disease pathways among adults. Data were extracted following a standardized protocol. We used DerSimonian and Laird random-effect models to compute the weighted mean differences (WMDs) and 95% CIs. We also examined potential modification by intervention duration, design, age, sex, comorbidities, and the form and amount of cocoa flavanol intake. RESULTS: We included 19 RCTs that comprised 1131 participants, and the number of studies for a specific biomarker varied. The amount of cocoa flavanols ranged from 166 to 2110 mg/d, and intervention duration ranged from 2 to 52 wk. Cocoa flavanol intake significantly improved insulin sensitivity and lipid profile. The WMDs between treatment and placebo were -0.10 mmol/L (95% CI: -0.16, -0.04 mmol/L) for total triglycerides, 0.06 mmol/L (95% CI: 0.02, 0.09 mmol/L) for HDL cholesterol, -2.33 µIU/mL (95% CI: -3.47, -1.19 µIU/mL) for fasting insulin, -0.93 (95% CI: -1.31, -0.55) for the homeostatic model assessment of insulin resistance, 0.03 (95% CI: 0.01, 0.05) for the quantitative insulin sensitivity check index, 2.54 (95% CI: 0.63, 4.44) for the insulin sensitivity index, -0.83 mg/dL (95% CI: -0.88, -0.77 mg/dL) for C-reactive protein, and 85.6 ng/mL (95% CI: 16.0, 155 ng/mL) for vascular cell adhesion molecule 1. No significant associations were found for other biomarkers. None of the modifiers seemed to qualitatively modify the effects of cocoa flavanol intake. CONCLUSIONS: Our study suggests that cocoa flavanol intake has favorable effects on select cardiometabolic biomarkers among adults. These findings support the need for large long-term RCTs to assess whether cocoa flavanol intake reduces the risk of diabetes and cardiovascular events.


Assuntos
Cacau/química , Doenças Cardiovasculares/prevenção & controle , Flavonóis/química , Flavonóis/farmacologia , Biomarcadores , Humanos
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