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1.
Sensors (Basel) ; 24(10)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38794004

RESUMO

Addressing common challenges such as limited indicators, poor adaptability, and imprecise modeling in gas pre-warning systems for driving faces, this study proposes a hybrid predictive and pre-warning model grounded in time-series analysis. The aim is to tackle the effects of broad application across diverse mines and insufficient data on warning accuracy. Firstly, we introduce an adaptive normalization (AN) model for standardizing gas sequence data, prioritizing recent information to better capture the time-series characteristics of gas readings. Coupled with the Gated Recurrent Unit (GRU) model, AN demonstrates superior forecasting performance compared to other standardization techniques. Next, Ensemble Empirical Mode Decomposition (EEMD) is used for feature extraction, guiding the selection of the Variational Mode Decomposition (VMD) order. Minimal decomposition errors validate the efficacy of this approach. Furthermore, enhancements to the transformer framework are made to manage non-linearities, overcome gradient vanishing, and effectively analyze long time-series sequences. To boost versatility across different mining scenarios, the Optuna framework facilitates multiparameter optimization, with xgbRegressor employed for accurate error assessment. Predictive outputs are benchmarked against Recurrent Neural Networks (RNN), GRU, Long Short-Term Memory (LSTM), and Bidirectional LSTM (BiLSTM), where the hybrid model achieves an R-squared value of 0.980975 and a Mean Absolute Error (MAE) of 0.000149, highlighting its top performance. To cope with data scarcity, bootstrapping is applied to estimate the confidence intervals of the hybrid model. Dimensional analysis aids in creating real-time, relative gas emission metrics, while persistent anomaly detection monitors sudden time-series spikes, enabling unsupervised early alerts for gas bursts. This model demonstrates strong predictive prowess and effective pre-warning capabilities, offering technological reinforcement for advancing intelligent coal mine operations.

2.
Neurosurg Rev ; 47(1): 235, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38795181

RESUMO

PURPOSE: This study investigated the value of whole tumor apparent diffusion coefficient (ADC) histogram parameters and magnetic resonance imaging (MRI) semantic features in predicting meningioma progesterone receptor (PR) expression. MATERIALS AND METHODS: The imaging, pathological, and clinical data of 53 patients with PR-negative meningiomas and 52 patients with PR-positive meningiomas were retrospectively reviewed. The whole tumor was outlined using Firevoxel software, and the ADC histogram parameters were calculated. The differences in ADC histogram parameters and MRI semantic features were compared between the two groups. The predictive values of parameters for PR expression were assessed using receiver operating characteristic curves. The correlation between whole-tumor ADC histogram parameters and PR expression in meningiomas was also analyzed. RESULTS: Grading was able to predict the PR expression in meningiomas (p = 0.012), though the semantic features of MRI were not (all p > 0.05). The mean, Perc.01, Perc.05, Perc.10, Perc.25, and Perc.50 histogram parameters were able to predict meningioma PR expression (all p < 0.05). The predictive performance of the combined histogram parameters improved, and the combination of grade and histogram parameters provided the optimal predictive value, with an area under the curve of 0.849 (95%CI: 0.766-0.911) and sensitivity, specificity, ACC, PPV, and NPV of 73.08%, 81.13%, 77.14%, 79.20%, and 75.40%, respectively. The mean, Perc.01, Perc.05, Perc.10, Perc.25, and Perc.50 histogram parameters were positively correlated with PR expression (all p < 0.05). CONCLUSION: Whole tumor ADC histogram parameters have additional clinical value in predicting PR expression in meningiomas.


Assuntos
Imagem de Difusão por Ressonância Magnética , Neoplasias Meníngeas , Meningioma , Receptores de Progesterona , Humanos , Meningioma/diagnóstico por imagem , Meningioma/patologia , Meningioma/metabolismo , Feminino , Pessoa de Meia-Idade , Masculino , Neoplasias Meníngeas/diagnóstico por imagem , Neoplasias Meníngeas/patologia , Neoplasias Meníngeas/metabolismo , Receptores de Progesterona/metabolismo , Adulto , Imagem de Difusão por Ressonância Magnética/métodos , Idoso , Estudos Retrospectivos , Valor Preditivo dos Testes
3.
Sci Adv ; 10(6): eadi4935, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38335292

RESUMO

Prostate cancer (PC) develops in a microenvironment where the stromal cells modulate adjacent tumor growth and progression. Here, we demonstrated elevated levels of monoamine oxidase B (MAOB), a mitochondrial enzyme that degrades biogenic and dietary monoamines, in human PC stroma, which was associated with poor clinical outcomes of PC patients. Knockdown or overexpression of MAOB in human prostate stromal fibroblasts indicated that MAOB promotes cocultured PC cell proliferation, migration, and invasion and co-inoculated prostate tumor growth in mice. Mechanistically, MAOB induces a reactive stroma with activated marker expression, increased extracellular matrix remodeling, and acquisition of a protumorigenic phenotype through enhanced production of reactive oxygen species. Moreover, MAOB transcriptionally activates CXCL12 through Twist1 synergizing with TGFß1-dependent Smads in prostate stroma, which stimulates tumor-expressed CXCR4-Src/JNK signaling in a paracrine manner. Pharmacological inhibition of stromal MAOB restricted PC xenograft growth in mice. Collectively, these findings characterize the contribution of MAOB to PC and suggest MAOB as a potential stroma-based therapeutic target.


Assuntos
Monoaminoxidase , Neoplasias da Próstata , Animais , Humanos , Masculino , Camundongos , Linhagem Celular Tumoral , Fibroblastos/metabolismo , Monoaminoxidase/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Transdução de Sinais , Microambiente Tumoral
4.
Int J Cancer ; 154(3): 548-560, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37727982

RESUMO

Telomerase activation is a crucial step in melanomagenesis, often occurring because of ultraviolet radiation (UVR)-induced mutations at the telomerase gene (TERT) promoter and rendering TERT transcription in response to the activated Raf-MAP kinase pathway by BRAFV600E mutation. Due to the excessively long telomeres in mice, this process does not occur during melanomagenesis in mouse models. To investigate the impact of telomere dysfunction on melanomagenesis, BrafV600E was induced in generations 1 and 4 (G1 and G4) of Tert-/- mice. Our findings revealed that, regardless of UVR exposure, melanoma development was delayed in G4 mice, which had shorter telomeres compared to G1 and wild-type C57BL/6J (G0) mice. Moreover, many G4 tumors displayed an accumulation of excessive DNA damage, as evidenced by increased γH2A.X staining. Tumors from UVR-exposed mice exhibited elevated p53 protein expression. Cultured tumor cells isolated from G4 mice displayed abundant chromosomal fusions and rearrangements, indicative of telomere dysfunction in these cells. Additionally, tumor cells derived from UVB-exposed mice exhibited constitutively elevated expression of mutant p53 proteins, suggesting that p53 was a target of UVB-induced mutagenesis. Taken together, our findings suggest that telomere dysfunction hampers melanomagenesis, and targeting telomere crisis-mediated genomic instability may hold promise for the prevention and treatment of melanoma.


Assuntos
Melanoma , Proteínas Proto-Oncogênicas B-raf , Telomerase , Animais , Camundongos , Melanoma/genética , Melanoma/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Telomerase/genética , Telomerase/metabolismo , Telômero/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Raios Ultravioleta/efeitos adversos
5.
Shock ; 60(2): 255-261, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37278996

RESUMO

ABSTRACT: Mitochondrial damage is an important cause of heart dysfunction after severe burn injury. However, the pathophysiological process remains unclear. This study aims to examine the mitochondrial dynamics in the heart and the role of µ-calpain, a cysteine protease, in this scenario. Rats were subjected to severe burn injury treatment, and the calpain inhibitor MDL28170 was administered intravenously 1 h before or after burn injury. Rats in the burn group displayed weakened heart performance and decreased mean arterial pressure, which was accompanied by a diminishment of mitochondrial function. The animals also exhibited higher levels of calpain in mitochondria, as reflected by immunofluorescence staining and activity tests. In contrast, treatment with MDL28170 before any severe burn diminished these responses to a severe burn. Burn injury decreased the abundance of mitochondria and resulted in a lower percentage of small mitochondria and a higher percentage of large mitochondria. Furthermore, burn injury caused an increase in the fission protein DRP1 in the mitochondria and a decrease in the inner membrane fusion protein OPA1. Similarly, these alterations were also blocked by MDL28170. Of note, inhibition of calpain yielded the emergence of more elongated mitochondria along with membrane invagination in the middle of the longitude, which is an indicator of the fission process. Finally, MDL28170, administered 1 h after burn injury, preserved mitochondrial function and heart performance, and increased the survival rate. Overall, these results provided the first evidence that mitochondrial recruitment of calpain confers heart dysfunction after severe burn injury, which involves aberrant mitochondrial dynamics.


Assuntos
Queimaduras , Calpaína , Ratos , Animais , Dinâmica Mitocondrial , Mitocôndrias/metabolismo , Queimaduras/complicações , Queimaduras/tratamento farmacológico , Queimaduras/metabolismo
6.
Int J Mol Sci ; 24(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36674423

RESUMO

The incidence of heart failure mainly resulting from cardiac hypertrophy and fibrosis increases sharply in post-menopausal women compared with men at the same age, which indicates a cardioprotective role of estrogen. Previous studies in our group have shown that the novel estrogen receptor G Protein Coupled Receptor 30 (GPR30) could attenuate myocardial fibrosis caused by ischemic heart disease. However, the role of GPR30 in myocardial hypertrophy in ovariectomized mice has not been investigated yet. In this study, female mice with bilateral ovariectomy or sham surgery underwent transverse aortic constriction (TAC) surgery. After 8 weeks, mice in the OVX + TAC group exhibited more severe myocardial hypertrophy and fibrosis than mice in the TAC group. G1, the specific agonist of GPR30, could attenuate myocardial hypertrophy and fibrosis of mice in the OVX + TAC group. Furthermore, the expression of LC3II was significantly higher in the OVX + TAC group than in the OVX + TAC + G1 group, which indicates that autophagy might play an important role in this process. An in vitro study showed that G1 alleviated AngiotensionII (AngII)-induced hypertrophy and reduced the autophagy level of H9c2 cells, as revealed by LC3II expression and tandem mRFP-GFP-LC3 fluorescence analysis. Additionally, Western blot results showed that the AKT/mTOR pathway was inhibited in the AngII group, whereas it was restored in the AngII + G1 group. To further verify the mechanism, PI3K inhibitor LY294002 or autophagy activator rapamycin was added in the AngII + G1 group, and the antihypertrophy effect of G1 on H9c2 cells was blocked by LY294002 or rapamycin. In summary, our results demonstrate that G1 can attenuate cardiac hypertrophy and fibrosis and improve the cardiac function of mice in the OVX + TAC group through AKT/mTOR mediated inhibition of autophagy. Thus, this study demonstrates a potential option for the drug treatment of pressure overload-induced cardiac hypertrophy in postmenopausal women.


Assuntos
Estenose da Valva Aórtica , Proteínas Proto-Oncogênicas c-akt , Camundongos , Feminino , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Estrogênio/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Cardiomegalia/tratamento farmacológico , Cardiomegalia/etiologia , Cardiomegalia/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Estenose da Valva Aórtica/patologia , Autofagia , Fibrose , Sirolimo/farmacologia , Sirolimo/uso terapêutico , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/metabolismo , Miocárdio/metabolismo
7.
Cancer Cell Int ; 22(1): 248, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35945579

RESUMO

A considerable number of glioblastoma (GBM) patients developed drug resistance to Temozolomide (TMZ) during chemotherapy, resulting in therapeutic failure and tumor recurrence. However, the exact mechanism of TMZ chemoresistance in GBM is still poorly clarified. As a novel identified lncRNA, LINC00520 was located on chromosome 14 and overexpressed in multiple human cancers. This study was designed and conducted to investigate the role and underlying mechanism of LINC00520 in GBM chemoresistance to TMZ. The qRT-PCR assay demonstrated that LINC00520 was significantly overexpressed in TMZ-sensitive and/or TMZ-resistant GBM cells (P < 0.001). The silencing of LINC00520 markedly reduced the cell viability, suppressed colony formation, induced cell apoptosis and G1/S phase arrest in TMZ-resistant cells (P < 0.001). In contrast, overexpression of LINC00520 conferred TMZ-resistant phenotype of GBM cells in vitro (P < 0.001). The orthotopic xenograft model was established and the results indicated that the volume of tumor xenografts in vivo was markedly inhibited by TMZ treatment after the silencing of LINC00520 (P < 0.001). Luciferase reporter assay and chromatin immunoprecipitation (ChIP) assay revealed a strong affinity of transcription factor STAT3 to the promoter regions of LINC00520, suggesting that STAT3 mediated the aberrant expression of LINC00520 in GBM. Further experiments demonstrated that LINC00520 could interact with RNA-binding protein LIN28B to inhibit autophagy and reduce DNA damage, thereby contributing to TMZ chemoresistance in GBM. These findings suggested that STAT3/LINC00520/LIN28B axis might be a promising target to improve TMZ chemoresistance of GBM.

8.
Exp Cell Res ; 411(1): 112937, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34863709

RESUMO

Spinal cord injury (SCI) often causes severe neurological dysfunction, and facilitating neurite elongation is particularly important in its treatment. Astrocytes (AS) play an important role in the central nervous system (CNS), and their high plasticity and versatility provide a feasible entry point for relevant research. Our purpose was to explore whether extracellular vesicles (EVs) from astrocytes (AS-EVs) and lipopolysaccharide (LPS)-preactivated astrocytes (LPAS-EVs) facilitate neurite elongation, to explore the underlying mechanism, and to verify whether these EVs promote locomotor recovery in rats. We used LPS to preactivate astrocytes and cocultured them with PC12 cells to observe neurite changes, then extracted and identified AS-EVs and LPAS-EVs and the role and mechanism of these EVs in facilitating neurite elongation was examined in vivo and vitro. We demonstrated that AS-EVs and LPAS-EVs facilitated the elongation of neurites and the recovery of rats with SCI. LPAS-EVs had a stronger effect than AS-EVs, by activating the Hippo pathway, promoting monopole spindle binding protein 1 (MOB1) expression, and reducing Yes-associated protein (YAP) levels. The data also suggest a feedback regulation between MOB1 and p-YAP/YAP. In sum, AS-EVs and LPAS-EVs can play an active role in facilitating neurite elongation by activating the Hippo pathway. These findings provide a new strategy for treating SCI and other CNS-related injuries.


Assuntos
Astrócitos/citologia , Vesículas Extracelulares/transplante , Via de Sinalização Hippo , Neuritos/fisiologia , Neurônios/citologia , Traumatismos da Medula Espinal/terapia , Animais , Astrócitos/metabolismo , Vesículas Extracelulares/metabolismo , Células PC12 , Ratos , Ratos Sprague-Dawley , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologia
9.
J Craniofac Surg ; 33(2): 674-678, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34387269

RESUMO

BACKGROUND: Burr-hole craniostomy (BHC) is considered to be the most effective method for the treatment of chronic subdural hematoma (CSDH), and middle meningeal artery embolization is a new therapy used in clinical practice in recent years to treat CSDH. However, the optimal therapeutic effect of these 2 procedures is still controversial. This study prospectively designed a modified burr-hole craniostomy (mBHC) with drainage to treat CSDH. METHODS: A total of 101 patients diagnosed with CSDH from January 2019 to April 2020 were prospectively included in this study. They were divided into BHC and mBHC groups. Among them, 40 selected CSDH patients received mBHC treatment. For comparison, 61 CSDH patients who received BHC treatment were used as the control group. Primary outcomes were hematoma recurrence and postoperative complications. Secondary outcomes included midline recovery, hematoma clearance, operation time, and hospital stay. The Chi-square test was used to compare the 6-month follow-up results between the 2 groups. RESULTS: Among patients treated with mBHC, 39 patients had a good prognosis, and one 87-year-old patient with bilateral hematoma died of postoperative heart failure. Of the patients treated with BHC, 52 patients had good prognoses, and one 53-year-old patient with unilateral hematoma died of postoperative acute intracranial bleeding. During the 6-month follow-up period, no relapse occurred in the patients treated with mBHC, whereas 8 (13%) of the patients treated with BHC relapsed. There was a significant difference in the recurrence rate between the 2 groups (P < 0.05). In addition, midline recovery, hematoma clearance rate, operation time, and complications were found to be significantly different statistically (P < 0.05), and other characteristics of operation and outcome were not significantly different (P > 0.05) between the 2 groups. CONCLUSIONS: Modified burr-hole craniostomy has a positive therapeutic effect on patients with CSDH and is more effective than conventional BHC therapy.


Assuntos
Hematoma Subdural Crônico , Adulto , Drenagem/métodos , Hematoma/cirurgia , Hematoma Subdural Crônico/cirurgia , Humanos , Recidiva , Estudos Retrospectivos , Resultado do Tratamento , Trepanação
10.
Comput Math Methods Med ; 2021: 4883509, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34956398

RESUMO

Accumulating studies revealed association between development of glioma and miRNA dysregulation. A case in point is miR-381-3p, but its mechanism in glioma is unclear yet. In this work, we confirmed that overexpressed miR-381-3p repressed biological functions of glioma cells. Additionally, we also discovered that upregulated anthrax toxin receptor 1 (ANTXR1) was negatively mediated by miR-381-3p. We further proved that miR-381-3p-targeted ANTXR1 was able to counteract the suppression of miR-381-3p on biological functions of glioma. We concluded that miR-381-3p and ANTXR1 were both important factors in modulating glioma progression. miR-381-3p/ANTXR1 axis is expected to be a molecular target for glioma.


Assuntos
Neoplasias Encefálicas/genética , Glioma/genética , MicroRNAs/genética , Proteínas dos Microfilamentos/antagonistas & inibidores , Receptores de Superfície Celular/antagonistas & inibidores , Carcinógenos/antagonistas & inibidores , Linhagem Celular Tumoral , Biologia Computacional , Progressão da Doença , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas dos Microfilamentos/genética , Receptores de Superfície Celular/genética , Regulação para Cima
11.
Appl Radiat Isot ; 176: 109900, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34428675

RESUMO

A new universal, flexible firmware has been implemented on field -programmable gate array (FPGA) for gamma-ray spectroscopy. The firmware of the FPGA runs on a digitizer that we developed ourselves. The present paper describes the detailed architecture of the firmware, including the trapezoidal shaper, peak detection, pulse height analyzer, and pile-up rejection. Gamma-ray spectroscopy measurements are made using a NaI(Tl) detector, CdZnTe detector, and HPGe detector.

12.
Proc Natl Acad Sci U S A ; 118(26)2021 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-34155099

RESUMO

Multiple independent sequence variants of the hTERT locus have been associated with telomere length and cancer risks in genome-wide association studies. Here, we identified an intronic variable number tandem repeat, VNTR2-1, as an enhancer-like element, which activated hTERT transcription in a cell in a chromatin-dependent manner. VNTR2-1, consisting of 42-bp repeats with an array of enhancer boxes, cooperated with the proximal promoter in the regulation of hTERT transcription by basic helix-loop-helix transcription factors and maintained hTERT expression during embryonic stem-cell differentiation. Genomic deletion of VNTR2-1 in MelJuSo melanoma cells markedly reduced hTERT transcription, leading to telomere shortening, cellular senescence, and impairment of xenograft tumor growth. Interestingly, VNTR2-1 lengths varied widely in human populations; hTERT alleles with shorter VNTR2-1 were underrepresented in African American centenarians, indicating its role in human aging. Therefore, this polymorphic element is likely a missing link in the telomerase regulatory network and a molecular basis for genetic diversities of telomere homeostasis and age-related disease susceptibilities.


Assuntos
Repetições Minissatélites/genética , Polimorfismo Genético , Telomerase/genética , Ativação Transcricional , Negro ou Afro-Americano/genética , Idoso de 80 Anos ou mais , Animais , Sequência de Bases , Diferenciação Celular/genética , Linhagem Celular , Proliferação de Células/genética , Cromossomos Artificiais Bacterianos/genética , Elementos E-Box/genética , Genoma Humano , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Camundongos Nus , Neoplasias/genética , Neoplasias/patologia , Regiões Promotoras Genéticas , Ligação Proteica/genética , Deleção de Sequência/genética , Homeostase do Telômero/genética
13.
Bioinformatics ; 37(19): 3263-3269, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-33974010

RESUMO

MOTIVATION: Aligning single-cell transcriptomes is important for the joint analysis of multiple single-cell RNA sequencing datasets, which in turn is vital to establishing a holistic cellular landscape of certain biological processes. Although numbers of approaches have been proposed for this problem, most of which only consider mutual neighbors when aligning the cells without taking into account known cell type annotations. RESULTS: In this work, we present MAT2 that aligns cells in the manifold space with a deep neural network employing contrastive learning strategy. Compared with other manifold-based approaches, MAT2 has two-fold advantages. Firstly, with cell triplets defined based on known cell type annotations, the consensus manifold yielded by the alignment procedure is more robust especially for datasets with limited common cell types. Secondly, the batch-effect-free gene expression reconstructed by MAT2 can better help annotate cell types. Benchmarking results on real scRNA-seq datasets demonstrate that MAT2 outperforms existing popular methods. Moreover, with MAT2, the hematopoietic stem cells are found to differentiate at different paces between human and mouse. AVAILABILITY AND IMPLEMENTATION: MAT2 is publicly available at https://github.com/Zhang-Jinglong/MAT2. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

14.
Diabetes ; 69(6): 1164-1177, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32184272

RESUMO

Branched chain amino acids (BCAAs) are associated with the progression of obesity-related metabolic disorders, including type 2 diabetes and nonalcoholic fatty liver disease. However, whether BCAAs disrupt the homeostasis of hepatic glucose and lipid metabolism remains unknown. In this study, we observed that BCAAs supplementation significantly reduced high-fat (HF) diet-induced hepatic lipid accumulation while increasing the plasma lipid levels and promoting muscular and renal lipid accumulation. Further studies demonstrated that BCAAs supplementation significantly increased hepatic gluconeogenesis and suppressed hepatic lipogenesis in HF diet-induced obese (DIO) mice. These phenotypes resulted from severe attenuation of Akt2 signaling via mTORC1- and mTORC2-dependent pathways. BCAAs/branched-chain α-keto acids (BCKAs) chronically suppressed Akt2 activation through mTORC1 and mTORC2 signaling and promoted Akt2 ubiquitin-proteasome-dependent degradation through the mTORC2 pathway. Moreover, the E3 ligase Mul1 played an essential role in BCAAs/BCKAs-mTORC2-induced Akt2 ubiquitin-dependent degradation. We also demonstrated that BCAAs inhibited hepatic lipogenesis by blocking Akt2/SREBP1/INSIG2a signaling and increased hepatic glycogenesis by regulating Akt2/Foxo1 signaling. Collectively, these data demonstrate that in DIO mice, BCAAs supplementation resulted in serious hepatic metabolic disorder and severe liver insulin resistance: insulin failed to not only suppress gluconeogenesis but also activate lipogenesis. Intervening BCAA metabolism is a potential therapeutic target for severe insulin-resistant disease.


Assuntos
Aminoácidos de Cadeia Ramificada/farmacologia , Dieta Hiperlipídica/efeitos adversos , Transtornos do Metabolismo dos Lipídeos/induzido quimicamente , Fígado/efeitos dos fármacos , Obesidade/complicações , Proteínas Proto-Oncogênicas c-akt/metabolismo , Aminoácidos de Cadeia Ramificada/administração & dosagem , Animais , Células Cultivadas , Gorduras na Dieta/administração & dosagem , Gorduras na Dieta/efeitos adversos , Proteína Forkhead Box O1/genética , Proteína Forkhead Box O1/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Rim/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Músculo Esquelético/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Distribuição Aleatória , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
15.
Theranostics ; 10(5): 2422-2435, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32104514

RESUMO

Macrophages are essential for wound repair after myocardial infarction (MI). CD226, a member of immunoglobulin superfamily, is expressed on inflammatory monocytes, however, the role of CD226 in infarct healing and the effect of CD226 on macrophage remain unknown. Methods: Wild type and CD226 knockout (CD226 KO) mice were subjected to permanent coronary ligation. CD226 expression, cardiac function and ventricular remodeling were evaluated. Profile of macrophages, myofibroblasts, angiogenesis and monocytes mobilization were determined. Results: CD226 expression increased in the infarcted heart, with a peak on day 7 after MI. CD226 KO attenuated infarct expansion and improved infarct healing after MI. CD226 deletion resulted in increased F4/80+ CD206+ M2 macrophages and diminished Mac-3+ iNOS+ M1 macrophages accumulation in the infarcted heart, as well as enrichment of α-smooth muscle actin positive myofibroblasts and Ki67+ CD31+ endothelial cells, leading to increased reparative collagen deposition and angiogenesis. Furthermore, CD226 deletion restrained inflammatory monocytes mobilization, as revealed by enhanced retention of Ly6Chi monocytes in the spleen associated with a decrease of Ly6Chi monocytes in the peripheral blood, whereas local proliferation of macrophage in the ischemic heart was not affected by CD226 deficiency. In vitro studies using bone marrow-derived macrophages showed that CD226 deletion potentiated M2 polarization and suppressed M1 polarization. Conclusion: CD226 expression is dramatically increased in the infarcted heart, and CD226 deletion improves post-infarction healing and cardiac function by favoring macrophage polarization towards reparative phenotype. Thus, inhibition of CD226 may represent a novel therapeutic approach to improve wound healing and cardiac function after MI.


Assuntos
Antígenos de Diferenciação de Linfócitos T/metabolismo , Macrófagos/metabolismo , Infarto do Miocárdio/metabolismo , Remodelação Ventricular , Animais , Antígenos de Diferenciação de Linfócitos T/genética , Células Endoteliais/metabolismo , Ativação de Macrófagos/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Monócitos/metabolismo , Infarto do Miocárdio/patologia , Miocárdio/metabolismo , Fenótipo , Cicatrização
16.
Mol Metab ; 20: 128-137, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30595550

RESUMO

OBJECTIVE: Nonalcoholic steatohepatitis (NASH) is closely associated with metabolic syndrome and increases the risk for end-stage liver disease, such as cirrhosis and hepatocellular carcinoma. Despite this, the molecular events that influence NASH pathogenesis remain poorly understood. The objectives of the current study are to delineate the transcriptomic and proteomic signatures of NASH liver, to identify potential pathogenic pathways and factors, and to critically assess their role in NASH pathogenesis. METHODS: We performed RNA sequencing and quantitative proteomic analyses on the livers from healthy and diet-induced NASH mice. We examined the association between plasma levels of TSK, a newly discovered hepatokine, and NASH pathologies and reversal in response to dietary switch in mice. Using TSK knockout mouse model, we determined how TSK deficiency modulates key aspects of NASH pathogenesis. RESULTS: RNA sequencing and quantitative proteomic analyses revealed that diet-induced NASH triggers concordant reprogramming of the liver transcriptome and proteome in mice. NASH pathogenesis is linked to elevated plasma levels of the hepatokine TSK, whereas dietary switch reverses NASH pathologies and reduces circulating TSK concentrations. Finally, TSK inactivation protects mice from diet-induced NASH and liver transcriptome remodeling. CONCLUSIONS: Global transcriptomic and proteomic profiling of healthy and NASH livers revealed the molecular signatures of diet-induced NASH and dysregulation of the liver secretome. Our study illustrates a novel pathogenic mechanism through which elevated TSK in circulation promotes NASH pathologies, thereby revealing a potential target for therapeutic intervention.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/genética , Hepatopatia Gordurosa não Alcoólica/genética , Proteoglicanas/genética , Proteoma/genética , Transcriptoma , Animais , Dieta Hiperlipídica/efeitos adversos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Proteoglicanas/metabolismo , Proteoma/metabolismo
17.
Cardiovasc Res ; 114(10): 1335-1349, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29668847

RESUMO

Aims: The farnesoid X receptor (FXR) is a member of the metabolic nuclear receptor superfamily that plays a critical regulatory role in cardiovascular physiology/pathology. However, the role of systemic FXR activation in the chronic phase in myocardial infarction (MI)-induced cardiac remodelling and dysfunction remains unclear. In this study, we aimed to elucidate the role of long-term FXR activation on post-MI cardiac remodelling and dysfunction. Methods and results: Mice underwent either MI surgery or sham operation. At 1 week after MI, both sham and MI mice were gavaged with 25 mg/kg/d of a synthetic FXR agonist (GW4064) or a vehicle control for 7 weeks, and cardiac performance was assessed by consecutive echocardiography studies. Administration of GW4064 significantly increased left ventricular ejection fraction at 4 weeks and 8 weeks after MI (both P < 0.01). Moreover, GW4064 treatment increased angiogenesis and mitochondrial biogenesis, reduced cardiomyocyte loss and inflammation, and ameliorated cardiac remodelling as evidenced by heart weight, lung weight, atrial natriuretic peptide/brain natriuretic peptide levels, and myocardial fibrosis at 8 weeks post-MI. At the molecular level, GW4064 significantly increased FXR mRNA expression and transcriptional activity in heart tissue. Moreover, over-expression of myocardial FXR failed to exert significant cardioprotection in vivo, indicating that GW4064 improved post-MI heart remodelling and function independent of myocardial FXR expression/activity. Among the four down-stream soluble molecules of FXR, plasma adiponectin was most significantly increased by GW4064. In cultured adipocytes, GW4064 increased mRNA levels and protein expression of adiponectin. Conditioned medium of GW4064-treated adipocytes activated AMPK-PGC-1α signalling and reduced hypoxia-induced cardiomyocyte apoptosis, all of which were attenuated by an adiponectin neutralizing anti-body. More importantly, when knocking-out adiponectin in mice, the cardioprotective effects of GW4064 were attenuated. Conclusions: We are the first to show that FXR agonism ameliorated post-MI cardiac dysfunction and remodelling by stimulating adiponectin secretion. Thus, we demonstrated that FXR agonism is a potential therapeutic strategy in post-MI heart failure.


Assuntos
Adiponectina/metabolismo , Ventrículos do Coração/efeitos dos fármacos , Isoxazóis/farmacologia , Infarto do Miocárdio/tratamento farmacológico , Receptores Citoplasmáticos e Nucleares/agonistas , Disfunção Ventricular Esquerda/prevenção & controle , Função Ventricular Esquerda/efeitos dos fármacos , Remodelação Ventricular/efeitos dos fármacos , Células 3T3-L1 , Adiponectina/deficiência , Adiponectina/genética , Animais , Apoptose/efeitos dos fármacos , Modelos Animais de Doenças , Ventrículos do Coração/metabolismo , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias Cardíacas/efeitos dos fármacos , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/patologia , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Biogênese de Organelas , Estresse Oxidativo/efeitos dos fármacos , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Transdução de Sinais/efeitos dos fármacos , Volume Sistólico/efeitos dos fármacos , Fatores de Tempo , Disfunção Ventricular Esquerda/metabolismo , Disfunção Ventricular Esquerda/patologia , Disfunção Ventricular Esquerda/fisiopatologia
18.
Yi Chuan ; 40(3): 237-249, 2018 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-29576547

RESUMO

H3K4me3 is an important epigenetic modification that plays a critical role in maintaining self-renewal of mouse embryonic stem cells (mESCs). H3K4me3 is catalyzed mainly by the mixed lineage leukemia (MLL) methyl-transferase complex. ASH2L, a core subunit of the MLL complex, participates in regulating the open state of chromatin in mESCs. There are two isoforms of the ASH2L protein: ASH2L-1 (80 kDa), which only exists in mouse embryonic fibroblasts and ASH2L-2 (65 kDa), which is the predominant isoform in mESCs. The roles of Ash2l-1 and Ash2l-2 in mESCs have not yet been elucidated. In this study, we established Ash2l-1 -/- and Ash2l-2 -/- knockout mESCs using CRISPR/Cas9. Alkaline phosphatase (AP) staining, immunofluorescence staining, and qRT-PCR showed that there were no obvious differences on the expression level of AP and pluripotent transcription factors (Nanog, Oct4, sox2 and Klf4) among Ash2l-1 -/- mESCs, Ash2l-2 -/- mESCs and wild type (WT) mESCs. However, analysis of embryoid body (EB) differentiation showed that the expression level of Snai2 (ectoderm gene) and Gata4 (endoderm gene) in Ash2l-1 -/- EBs was significantly lower than that in WT EBs (P<0.01). Western blotting assay revealed that the expression of ASH2L-2 was significantly increased (P<0.01) in Ash2l-1 -/- mESCs and vice versa. However, there were no obvious differences on the genomic H3K4me3 level among Ash2l-1 -/- mESCs, Ash2l-2 -/- mESCs and WT mESCs. These results indicate that there exist compensation effects between Ash2l-1 and Ash2l-2. Bioinformatic analysis predicted that there were three and 16 potential binding sites for pluripotency transcription factors located in the promoter of Ash2l-1 and Ash2l-2, respectively. Theses transcription factors may mediate the compensation effect between Ash2l-1 and Ash2l-2. Collectively, these results indicate that the compensation effects between Ash2l-1 and Ash2l-2 may be involved in the maintenance of mESCs pluripotency and the regulation of genomic H3K4me3.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Camundongos/embriologia , Camundongos/metabolismo , Células-Tronco Embrionárias Murinas/citologia , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Animais , Proteínas de Ligação a DNA/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Histonas/genética , Histonas/metabolismo , Fator 4 Semelhante a Kruppel , Masculino , Camundongos/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células-Tronco Embrionárias Murinas/metabolismo , Proteínas Nucleares/genética , Fatores de Transcrição/genética
19.
Cell Death Dis ; 9(2): 224, 2018 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-29445086

RESUMO

Unipotent spermatogonial stem cells (SSCs) can be efficiently reprogrammed into pluripotent stem cells only by manipulating the culture condition, without introducing exogenous reprogramming factors. This phenotype raises the hypothesis that the endogenous transcription factors (TFs) in SSCs may facilitate reprogramming to acquire pluripotency. In this study, we screened a pool of SSCs TFs (Bcl6b, Lhx1, Foxo1, Plzf, Id4, Taf4b, and Etv5), and found that oncogene Etv5 could dramatically increase the efficiency of induced pluripotent stem cells (iPSCs) generation when combined with Yamanaka factors. We also demonstrated that Etv5 could promote mesenchymal-epithelial transition (MET) at the early stage of reprogramming by regulating Tet2-miR200s-Zeb1 axis. In addition, Etv5 knockdown in mouse embryonic stem cells (mESCs) could decrease the genomic 5hmC level by downregulating Tet2. Furthermore, the embryoid body assay revealed that Etv5 could positively regulate primitive endoderm specification through regulating Gata6 and negatively regulate epiblast specification by inhibiting Fgf5 expression. In summary, our findings provide insights into understanding the regulation mechanisms of Etv5 under the context of somatic reprogramming, mESCs maintenance, and differentiation.


Assuntos
Reprogramação Celular , Proteínas de Ligação a DNA/genética , Endoderma/metabolismo , Transição Epitelial-Mesenquimal/genética , Regulação da Expressão Gênica no Desenvolvimento , Células-Tronco Embrionárias Murinas/metabolismo , Fatores de Transcrição/genética , Animais , Diferenciação Celular , Proliferação de Células , Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/metabolismo , Dioxigenases , Embrião de Mamíferos , Endoderma/citologia , Endoderma/crescimento & desenvolvimento , Feminino , Fibroblastos/citologia , Fibroblastos/metabolismo , Fator de Transcrição GATA6/genética , Fator de Transcrição GATA6/metabolismo , Perfilação da Expressão Gênica , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , MicroRNAs/genética , MicroRNAs/metabolismo , Células-Tronco Embrionárias Murinas/citologia , Cultura Primária de Células , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo
20.
J Gastroenterol Hepatol ; 33(8): 1538-1547, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29384233

RESUMO

BACKGROUND AND AIM: It has been well documented that Notch signaling is involved in liver regeneration. However, the exact molecular mechanism mediating this process is not fully elucidated. The current study aimed to investigate the role of Notch signaling regulating cell cycle in proliferating hepatocytes in liver regeneration after partial hepatectomy (PHx, 67% resection) and the related molecular mechanism. METHODS: Partial hepatectomy was performed in Sprague Dawley rats, and remnant livers were harvested 0, 1, 3, 5, and 7 days after operation, and primary hepatocytes were isolated to investigate the molecular mechanism. RESULTS: Notch signaling activation and hepatocyte proliferation were significantly increased after PHx, while treatment with FLI-06, the inhibitor of γ-secreting enzyme, blocked these trends. Besides, inhibition of Notch signaling led to dysregulation of cell cycle and cell-cycle components. Furthermore, Akti-1/2 (a selective Akt inhibitor) and PX-478 (a selective Hif-1α inhibitor) inhibited hepatocyte proliferation and liver regeneration after PHx, and the effect of downstream molecules activation by Jagged-1 (Notch-1 ligand) in hepatocytes was abolished by FLI-06, Akti-1/2, and PX-478. CONCLUSION: The current study demonstrated for the first time that Notch signaling regulated cell cycle in proliferating hepatocytes involved in liver regeneration through NICD/Akt Akt/Hif-1α pathway.


Assuntos
Ciclo Celular/genética , Ciclo Celular/fisiologia , Proliferação de Células/genética , Proliferação de Células/fisiologia , Hepatócitos/citologia , Hepatócitos/fisiologia , Regeneração Hepática/genética , Regeneração Hepática/fisiologia , Receptores Notch/fisiologia , Transdução de Sinais/fisiologia , Animais , Células HEK293 , Hepatectomia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/fisiologia , Masculino , Proteínas Proto-Oncogênicas c-akt/fisiologia , Ratos Sprague-Dawley
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