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1.
EMBO Rep ; 25(5): 2441-2478, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38649663

RESUMO

Ago2 differentially regulates oncogenic and tumor-suppressive miRNAs in cancer cells. This discrepancy suggests a secondary event regulating Ago2/miRNA action in a context-dependent manner. We show here that a positive charge of Ago2 K212, that is preserved by SIR2-mediated Ago2 deacetylation in cancer cells, is responsible for the direct interaction between Ago2 and Caveolin-1 (CAV1). Through this interaction, CAV1 sequesters Ago2 on the plasma membranes and regulates miRNA-mediated translational repression in a compartment-dependent manner. Ago2/CAV1 interaction plays a role in miRNA-mediated mRNA suppression and in miRNA release via extracellular vesicles (EVs) from tumors into the circulation, which can be used as a biomarker of tumor progression. Increased Ago2/CAV1 interaction with tumor progression promotes aggressive cancer behaviors, including metastasis. Ago2/CAV1 interaction acts as a secondary event in miRNA-mediated suppression and increases the complexity of miRNA actions in cancer.


Assuntos
Proteínas Argonautas , Caveolina 1 , MicroRNAs , Metástase Neoplásica , Animais , Humanos , Camundongos , Proteínas Argonautas/metabolismo , Proteínas Argonautas/genética , Caveolina 1/metabolismo , Caveolina 1/genética , Linhagem Celular Tumoral , Vesículas Extracelulares/metabolismo , Regulação Neoplásica da Expressão Gênica , MicroRNAs/metabolismo , MicroRNAs/genética , Neoplasias/metabolismo , Neoplasias/genética , Neoplasias/patologia , Ligação Proteica , Sirtuína 2/metabolismo , Sirtuína 2/genética
2.
Int J Mol Sci ; 23(2)2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-35054997

RESUMO

Hericium erinaceus (HE) is a common edible mushroom consumed in several Asian countries and considered to be a medicinal mushroom with neuroprotective effects. Erinacine A (EA) is a bioactive compound in Hericium erinaceus mycelium (HEM) that has been shown to have a neuroprotective effect against neurodegenerative diseases, e.g., Parkinson's disease (PD). Although the etiology of PD is still unclear, neuroinflammation may play an important role in causing dopaminergic neuron loss, which is a pathological hallmark of PD. However, glial cell activation has a close relationship with neuroinflammation. Thus, this study aimed to investigate the anti-neuroinflammatory and neuroprotective effects of EA on lipopolysaccharide (LPS)-induced glial cell activation and neural damage in vitro and in vivo. For the in vitro experiments, glial cells, BV-2 microglial cells and CTX TNA2 astrocytes were pretreated with EA and then stimulated with LPS and/or IFN-γ. The expression of proinflammatory factors in the cells and culture medium was analyzed. In addition, differentiated neuro-2a (N2a) cells were pretreated with EA or HEM and then stimulated with LPS-treated BV-2 conditioned medium (CM). The cell viability and the amount of tyrosine hydroxylase (TH) and mitogen-activated protein kinases (MAPKs) were analyzed. In vivo, rats were given EA or HEM by oral gavage prior to injection of LPS into the substantia nigra (SN). Motor coordination of the rats and the expression of proinflammatory mediators in the midbrain were analyzed. EA pretreatment prevented LPS-induced iNOS expression and NO production in BV-2 cells and TNF-α expression in CTX TNA2 cells. In addition, both EA and HEM pretreatment significantly increased cell viability and TH expression and suppressed the phosphorylation of JNK and NF- κB in differentiated N2a cells treated with CM. In vivo, both EA and HEM significantly improved motor dysfunction in the rotarod test and the amphetamine-induced rotation test and reduced the expression of TNF-α, IL-1ß and iNOS in the midbrain of rats intranigrally injected with LPS. The results demonstrate that EA ameliorates LPS-induced neuroinflammation and has neuroprotective properties.


Assuntos
Diterpenos/farmacologia , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Mediadores da Inflamação/metabolismo , Microglia/efeitos dos fármacos , Microglia/metabolismo , Fármacos Neuroprotetores/farmacologia , Animais , Morte Celular/efeitos dos fármacos , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Expressão Gênica , Lipopolissacarídeos/imunologia , Microglia/imunologia , Doenças Neuroinflamatórias/etiologia , Doenças Neuroinflamatórias/metabolismo , Doenças Neuroinflamatórias/patologia , Doença de Parkinson/etiologia , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Ratos
5.
PLoS One ; 12(4): e0174691, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28376119

RESUMO

BACKGROUND: The current literature focusing on the effect of obesity and overweight on lung function and fraction of exhaled nitric oxide (FeNO) in children, particularly among healthy children of non-European descent, remains controversial. Furthermore, whether the relationship of obesity and overweight with lung function and FeNO in children is modified by atopy is unclear. The objective of this study was to examine the effect of excess weight on lung function parameters and FeNO among Asian children, with a particular focus on exploring the potential effect modification by atopy. METHODS: We investigated the effect of excess weight on lung function and FeNO in a population sample of 1,717 children aged 5 to 18 years and explored the potential modifying effect of atopy. RESULTS: There were positive associations of body mass index (BMI) z-score with forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), peak expiratory flow (PEF), and forced expiratory flow at 25-75% (FEF25-75) (all P<0.001), after controlling for confounders. The beta coefficient for FEV1 (0.084) was smaller than that for FVC (0.111). In contrast, a negative association was found between BMI z-score and FEV1/FVC ratio (P<0.001) and FeNO (P = 0.03). A consistent pattern of association for lung function variables was observed when stratifying by atopy. There was a negative association of BMI z-score with FeNO in atopic subjects (P = 0.006), but not in non-atopic subjects (P = 0.46). CONCLUSIONS: Excess weight disproportionately impacts lung volumes and airflow in children from the general population, independent of atopic status. Excess weight inversely affects FeNO in atopic but not in non-atopic children.


Assuntos
Pulmão/fisiopatologia , Óxido Nítrico/fisiologia , Obesidade/fisiopatologia , Adolescente , Índice de Massa Corporal , Criança , Pré-Escolar , Expiração/fisiologia , Feminino , Volume Expiratório Forçado , Humanos , Hipersensibilidade Imediata/complicações , Hipersensibilidade Imediata/fisiopatologia , Masculino , Fluxo Máximo Médio Expiratório , Obesidade/complicações , Obesidade/patologia , Pico do Fluxo Expiratório , Ventilação Pulmonar , Testes de Função Respiratória , Capacidade Vital
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