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1.
Reprod Biol Endocrinol ; 22(1): 58, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38778410

RESUMO

BACKGROUND: The best method for selecting embryos ploidy is preimplantation genetic testing for aneuploidies (PGT-A). However, it takes more labour, money, and experience. As such, more approachable, non- invasive techniques were still needed. Analyses driven by artificial intelligence have been presented recently to automate and objectify picture assessments. METHODS: In present retrospective study, a total of 3448 biopsied blastocysts from 979 Time-lapse (TL)-PGT cycles were retrospectively analyzed. The "intelligent data analysis (iDA) Score" as a deep learning algorithm was used in TL incubators and assigned each blastocyst with a score between 1.0 and 9.9. RESULTS: Significant differences were observed in iDAScore among blastocysts with different ploidy. Additionally, multivariate logistic regression analysis showed that higher scores were significantly correlated with euploidy (p < 0.001). The Area Under the Curve (AUC) of iDAScore alone for predicting euploidy embryo is 0.612, but rose to 0.688 by adding clinical and embryonic characteristics. CONCLUSIONS: This study provided additional information to strengthen the clinical applicability of iDAScore. This may provide a non-invasive and inexpensive alternative for patients who have no available blastocyst for biopsy or who are economically disadvantaged. However, the accuracy of embryo ploidy is still dependent on the results of next-generation sequencing technology (NGS) analysis.


Assuntos
Aneuploidia , Blastocisto , Aprendizado Profundo , Diagnóstico Pré-Implantação , Humanos , Estudos Retrospectivos , Feminino , Diagnóstico Pré-Implantação/métodos , Adulto , Gravidez , Blastocisto/citologia , Testes Genéticos/métodos , Fertilização in vitro/métodos
2.
MedComm (2020) ; 4(5): e349, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37706196

RESUMO

Macrophages play diverse roles in development, homeostasis, and immunity. Accordingly, the dysfunction of macrophages is involved in the occurrence and progression of various diseases, such as coronavirus disease 2019 and atherosclerosis. The protective or pathogenic effect that macrophages exert in different conditions largely depends on their functional plasticity, which is regulated via signal transduction such as Janus kinase-signal transducer and activator of transcription, Wnt and Notch pathways, stimulated by environmental cues. Over the past few decades, the molecular mechanisms of signaling pathways in macrophages have been gradually elucidated, providing more alternative therapeutic targets for diseases treatment. Here, we provide an overview of the basic physiology of macrophages and expound the regulatory pathways within them. We also address the crucial role macrophages play in the pathogenesis of diseases, including autoimmune, neurodegenerative, metabolic, infectious diseases, and cancer, with a focus on advances in macrophage-targeted strategies exploring modulation of components and regulators of signaling pathways. Last, we discuss the challenges and possible solutions of macrophage-targeted therapy in clinical applications. We hope that this comprehensive review will provide directions for further research on therapeutic strategies targeting macrophage signaling pathways, which are promising to improve the efficacy of disease treatment.

3.
Hepatology ; 74(6): 3091-3109, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34320238

RESUMO

BACKGROUND AND AIMS: NAFLD has become a tremendous burden for public health; however, there is no drug for NAFLD therapy at present. Impaired endo-lysosome-mediated protein degradation is observed in a variety of metabolic disorders, such as atherosclerosis, type 2 diabetes mellitus, and NAFLD. Small integral membrane protein of lysosome/late endosome (SIMPLE) is a regulator of endosome-to-lysosome trafficking and cell signaling, but the role that SIMPLE plays in NAFLD progression remains unknown. Here we investigated SIMPLE function in NAFLD development and sophisticated mechanism therein. APPROACH AND RESULTS: This study found that in vitro knockdown of SIMPLE significantly aggravated lipid accumulation and inflammation in hepatocytes treated with metabolic stimulation. Consistently, in vivo experiments showed that liver-specific Simple-knockout (Simple-HKO) mice exhibited more severe high-fat diet (HFD)-induced, high-fat-high-cholesterol diet (HFHC)-induced, and methionine-choline-deficient diet (MCD)-induced steatosis, glucose intolerance, inflammation, and fibrosis than those fed with normal chow (NC) diet. Meanwhile, RNA-sequencing demonstrated the up-regulated signaling pathways and signature genes involved in lipid metabolism, inflammation, and fibrosis in Simple-HKO mice compared with control mice under metabolic stress. Mechanically, we found SIMPLE directly interact with epidermal growth factor receptor (EGFR). SIMPLE deficiency results in dysregulated degradation of EGFR, subsequently hyperactivated EGFR phosphorylation, thus exaggerating NAFLD development. Moreover, we demonstrated that using EGFR inhibitor or silencing EGFR expression could ameliorate lipid accumulation induced by the knockdown of SIMPLE. CONCLUSIONS: SIMPLE ameliorated NASH by prompting EGFR degradation and can be a potential therapeutic candidate for NASH.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Receptores ErbB/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Animais , Biópsia , Células Cultivadas , Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/genética , Dieta Hiperlipídica/efeitos adversos , Receptores ErbB/antagonistas & inibidores , Feminino , Técnicas de Silenciamento de Genes , Hepatócitos , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Fígado/metabolismo , Fígado/patologia , Lisossomos/metabolismo , Masculino , Camundongos , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Proteínas Nucleares/genética , Cultura Primária de Células , Proteólise , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética
4.
Circulation ; 137(14): 1486-1504, 2018 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-29229612

RESUMO

BACKGROUND: Cardiac hypertrophy and its resultant heart failure are among the most common causes of mortality worldwide. Abnormal protein degradation, especially the impaired lysosomal degradation of large organelles and membrane proteins, is involved in the progression of cardiac hypertrophy. However, the underlying mechanisms have not been fully elucidated. METHODS: We investigated cardiac transmembrane BAX inhibitor motif containing 1 (TMBIM1) mRNA and protein expression levels in samples from patients with heart failure and mice with aortic banding (AB)-induced cardiac hypertrophy. We generated cardiac-specific Tmbim1 knockout mice and cardiac-specific Tmbim1-overexpressing transgenic mice and then challenged them with AB surgery. We used microarray, confocal image, and coimmunoprecipitation analyses to identify the downstream targets of TMBIM1 in cardiac hypertrophy. Tmbim1/Tlr4 double-knockout mice were generated to investigate whether the effects of TMBIM1 on cardiac hypertrophy were Toll-like receptor 4 (TLR4) dependent. Finally, lentivirus-mediated TMBIM1 overexpression in a monkey AB model was performed to evaluate the therapeutic potential of TMBIM1. RESULTS: TMBIM1 expression was significantly downregulated on hypertrophic stimuli in both human and mice heart samples. Silencing cardiac Tmbim1 aggravated AB-induced cardiac hypertrophy. This effect was blunted by Tmbim1 overexpression. Transcriptome profiling revealed that the TLR4 signaling pathway was disrupted dramatically by manipulation of Tmbim1. The effects of TMBIM1 on cardiac hypertrophy were shown to be dependent on TLR4 in double-knockout mice. Fluorescent staining indicated that TMBIM1 promoted the lysosome-mediated degradation of activated TLR4. Coimmunoprecipitation assays confirmed that TMBIM1 directly interacted with tumor susceptibility gene 101 via a PTAP motif and accelerated the formation of multivesicular bodies that delivered TLR4 to the lysosomes. Finally, lentivirus-mediated TMBIM1 overexpression reversed AB-induced cardiac hypertrophy in monkeys. CONCLUSIONS: TMBIM1 protects against pathological cardiac hypertrophy through promoting the lysosomal degradation of activated TLR4. Our findings reveal the central role of TMBIM1 as a multivesicular body regulator in the progression of pathological cardiac hypertrophy, as well as the role of vesicle trafficking in signaling regulation during cardiac hypertrophy. Moreover, targeting TMBIM1 could be a novel therapeutic strategy for treating cardiac hypertrophy and heart failure.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Cardiomegalia/patologia , Insuficiência Cardíaca/patologia , Motivos de Aminoácidos , Animais , Proteínas Reguladoras de Apoptose/química , Proteínas Reguladoras de Apoptose/genética , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças , Complexos Endossomais de Distribuição Requeridos para Transporte/química , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Haplorrinos , Humanos , Lisossomos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
5.
Nat Med ; 23(6): 742-752, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28481357

RESUMO

Non-alcoholic steatohepatitis (NASH) is an increasingly prevalent liver pathology that can progress from non-alcoholic fatty liver disease (NAFLD), and it is a leading cause of cirrhosis and hepatocellular carcinoma. There is currently no pharmacological therapy for NASH. Defective lysosome-mediated protein degradation is a key process that underlies steatohepatitis and a well-recognized drug target in a variety of diseases; however, whether it can serve as a therapeutic target for NAFLD and NASH remains unknown. Here we report that transmembrane BAX inhibitor motif-containing 1 (TMBIM1) is an effective suppressor of steatohepatitis and a previously unknown regulator of the multivesicular body (MVB)-lysosomal pathway. Tmbim1 expression in hepatocytes substantially inhibited high-fat diet-induced insulin resistance, hepatic steatosis and inflammation in mice. Mechanistically, Tmbim1 promoted the lysosomal degradation of toll-like receptor 4 by cooperating with the ESCRT endosomal sorting complex to facilitate MVB formation, and the ubiquitination of Tmbim1 by the E3 ubiquitin ligase Nedd4l was required for this process. We also found that overexpression of Tmbim1 in the liver effectively inhibited a severe form of NAFLD in mice and NASH progression in monkeys. Taken together, these findings could lead to the development of promising strategies to treat NASH by targeting MVB regulators to properly orchestrate the lysosome-mediated protein degradation of key mediators of the disease.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Proteínas de Membrana/metabolismo , Corpos Multivesiculares/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Receptor 4 Toll-Like/metabolismo , Adolescente , Adulto , Animais , Western Blotting , Citocinas/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Feminino , Imunofluorescência , Células HEK293 , Células HeLa , Humanos , Imuno-Histoquímica , Lisossomos/metabolismo , Macaca fascicularis , Masculino , Camundongos , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Ubiquitina-Proteína Ligases Nedd4 , Reação em Cadeia da Polimerase , Tomografia por Emissão de Pósitrons , Células RAW 264.7 , Ubiquitina-Proteína Ligases/metabolismo , Adulto Jovem
6.
J Hepatol ; 65(1): 113-124, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27016281

RESUMO

BACKGROUND & AIMS: Dickkopf-3 (DKK3), a protein belonging to the DKK family, has been extensively investigated in the context of cancer, including liver cancer. However, the role of DKK3 in hepatic steatosis and related metabolic disorders remains largely unexplored. METHODS: We detected the expression of DKK3 in the fatty livers of NAFLD patients and of obese mice and investigated the function of DKK3 in hepatic steatosis and related metabolic disorders by using hepatocyte-specific DKK3 deficiency or overexpression obese mice induced by high fat diet (HFD) or genetic defect (ob/ob). The molecular mechanisms underlying DKK3-regulated hepatic steatosis were further explored and verified in mice. RESULTS: DKK3 expression was significantly decreased in the livers of NAFLD patients and of obese mice as well as in cultured hepatocytes stimulated with palmitate. Further investigation indicated that specific overexpression of DKK3 in hepatocytes enhanced insulin sensitivity and glucose tolerance, reduced the inflammatory response, and ameliorated the imbalance of lipid metabolism in response to HFD or genetic defects. In contrast, DKK3 deficiency in hepatocytes led to an almost complete reversal of these pathologies. Mechanistically, DKK3 combined with Apoptosis signal-regulating kinase 1 (ASK1) under palmitate stimulation, and thus inhibited the activation of the downstream P38/JNK pathway. Importantly, dominant-negative ASK1 blocked the accelerated effects of DKK3 deficiency, while the constitutively active form of ASK1 overcame the inhibitory effects of DKK3 overexpression on HFD-induced metabolic disorders in vivo. CONCLUSION: DKK3 functions as a negative regulator of insulin resistance, hepatic steatosis, and associated inflammatory responses, which depends on its inhibitory regulation of ASK1 activity. LAY SUMMARY: DKK3 expression is decreased in the non-alcoholic fatty liver of humans and mice. Adding DKK3 expression alleviates fatty liver in mice by inhibiting ASK1 activity.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Obesidade , Animais , Dieta Hiperlipídica , Hepatócitos , Humanos , Resistência à Insulina , Fígado , MAP Quinase Quinase Quinase 5 , Camundongos , Camundongos Endogâmicos C57BL
7.
Nat Commun ; 7: 10592, 2016 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-26882989

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is characterized by hepatic steatosis, insulin resistance and a systemic pro-inflammatory response. Here we show that tumour necrosis factor receptor-associated factor 3 (TRAF3) is upregulated in mouse and human livers with hepatic steatosis. After 24 weeks on a high-fat diet (HFD), obesity, insulin resistance, hepatic steatosis and inflammatory responses are significantly ameliorated in liver-specific TRAF3-knockout mice, but exacerbated in transgenic mice overexpressing TRAF3 in hepatocytes. The detrimental effects of TRAF3 on hepatic steatosis and related pathologies are confirmed in ob/ob mice. We further show that in response to HFD, hepatocyte TRAF3 binds to TGF-ß-activated kinase 1 (TAK1) to induce TAK1 ubiquitination and subsequent autophosphorylation, thereby enhancing the activation of downstream IKKß-NF-κB and MKK-JNK-IRS1(307) signalling cascades, while disrupting AKT-GSK3ß/FOXO1 signalling. The TRAF3-TAK1 interaction and TAK1 ubiquitination are indispensable for TRAF3-regulated hepatic steatosis. In conclusion, hepatocyte TRAF3 promotes HFD-induced or genetic hepatic steatosis in a TAK1-dependent manner.


Assuntos
Fígado Gorduroso/metabolismo , Hepatócitos/metabolismo , Resistência à Insulina , MAP Quinase Quinase Quinases/metabolismo , Fator 3 Associado a Receptor de TNF/metabolismo , Animais , Fígado Gorduroso/genética , Feminino , Humanos , Fígado/metabolismo , MAP Quinase Quinase Quinases/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ligação Proteica , Transdução de Sinais , Fator 3 Associado a Receptor de TNF/genética
8.
J Hepatol ; 64(1): 146-59, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26334576

RESUMO

BACKGROUND & AIMS: The hallmarks of hepatic ischemia/reperfusion (I/R) injury, a common clinical problem that occurs during liver surgical procedures, include severe cell death and inflammatory responses that contribute to early graft failure and a higher incidence of organ rejection. Unfortunately, effective therapeutic strategies are limited. Tumor necrosis factor receptor (TNFR)-associated factor (TRAF) 3 transduces apoptosis and/or inflammation-related signaling pathways to regulate cell survival and cytokine production. However, the role of TRAF3 in hepatic I/R-induced liver damage remains unknown. METHODS: Hepatocyte- or myeloid cell-specific TRAF3 knockdown or transgenic mice were subjected to an I/R model in vivo, and in vitro experiments were performed by treating primary hepatocytes from these mice with hypoxia/reoxygenation stimulation. The function of TRAF3 in I/R-induced liver damage and the potential underlying mechanisms were investigated through various phenotypic analyses and biological approaches. RESULTS: Hepatocyte-specific, but not myeloid cell-specific, TRAF3 deficiency reduced cell death, inflammatory cell infiltration, and cytokine production in both in vivo and in vitro hepatic I/R models, whereas hepatic TRAF3 overexpression resulted in the opposite effects. Mechanistically, TRAF3 directly binds to TAK1, which enhances the activation of the downstream NF-κB and JNK pathways. Importantly, inhibition of TAK1 almost completely reversed the TRAF3 overexpression-mediated exacerbation of I/R injury. CONCLUSIONS: TRAF3 is a novel hepatic I/R mediator that promotes liver damage and inflammation via TAK1-dependent activation of the JNK and NF-κB pathways. Inhibition of hepatic TRAF3 may represent a promising approach to protect the liver against I/R injury-related diseases.


Assuntos
Fígado/irrigação sanguínea , Traumatismo por Reperfusão/etiologia , Fator 3 Associado a Receptor de TNF/fisiologia , Animais , Feminino , Humanos , MAP Quinase Quinase Quinases/fisiologia , Sistema de Sinalização das MAP Quinases/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/fisiologia , Traumatismo por Reperfusão/prevenção & controle
9.
Hypertension ; 66(3): 604-16, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26269654

RESUMO

Neuronal death after ischemic stroke involves multiple pathophysiological events, as well as a complex molecular mechanism. Inhibiting a single therapeutic target that is involved in several ischemic signaling cascades may be a promising strategy for stroke management. Here, we report the versatile biological roles of tumor necrosis factor receptor-associated factor 3 (TRAF3) in ischemic stroke. Using several genetically manipulated mouse strains, we also demonstrated that TRAF3 inhibition can be neuroprotective. TRAF3 expression, which is robustly induced in response to ischemia/reperfusion (I/R) injury, was detected in neurons. Overexpression of TRAF3 in neurons led to aggravated neuronal loss and enlarged infarcts; these effects were reversed in TRAF3-knockout mice. Neuronal TRAF3 also contributed to c-Jun kinase-, nuclear factor κB- and Rac-1-induced neuronal death, inflammation, and oxidative stress. Mechanistically, we showed that TRAF3 interacts with transforming growth factor-ß-activated kinase 1 (TAK1) and potentiates phosphorylation and activation of TAK1. Phosphorylated TAK1 sequentially initiated activation of nuclear factor κB, Rac-1/NADPH oxidase, and c-Jun kinase/c-Jun signaling cascades. Using a combination of adenoviruses encoding dominant-negative TAK1 and the TAK1 inhibitor 5Z-7-oxozeaenol, we demonstrated that the TRAF3-mediated activation of ischemic cascades was TAK1-dependent. More importantly, the adverse phenotypes observed in TRAF3-overexpressing mice were completely reversed when the TRAF3-TAK1 interaction was prevented. Therefore, we have shown that TRAF3 is a central regulator of ischemic pathways, including nuclear factor κB, Rac-1, and c-Jun kinase signaling, via its interaction with and activation of TAK1. Furthermore, certain components of the TRAF3-TAK1 signaling pathway are potentially promising therapeutic targets in ischemic stroke.


Assuntos
Isquemia Encefálica/metabolismo , Morte Celular/fisiologia , Neurônios/metabolismo , Acidente Vascular Cerebral/metabolismo , Fator 3 Associado a Receptor de TNF/metabolismo , Animais , Isquemia Encefálica/patologia , MAP Quinase Quinase Quinases/genética , MAP Quinase Quinase Quinases/metabolismo , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Proteína Quinase 8 Ativada por Mitógeno/metabolismo , NF-kappa B/metabolismo , Neurônios/patologia , Transdução de Sinais/fisiologia , Acidente Vascular Cerebral/patologia , Fator 3 Associado a Receptor de TNF/genética , Regulação para Cima
10.
Hypertension ; 66(2): 356-67, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26034202

RESUMO

Cardiac hypertrophy, a common early symptom of heart failure, is regulated by numerous signaling pathways. Here, we identified tumor necrosis factor receptor-associated factor 3 (TRAF3), an adaptor protein in tumor necrosis factor-related signaling cascades, as a key regulator of cardiac hypertrophy in response to pressure overload. TRAF3 expression was upregulated in hypertrophied mice hearts and failing human hearts. Four weeks after aortic banding, cardiac-specific conditional TRAF3-knockout mice exhibited significantly reduced cardiac hypertrophy, fibrosis, and dysfunction. Conversely, transgenic mice overexpressing TRAF3 in the heart developed exaggerated cardiac hypertrophy in response to pressure overload. TRAF3 also promoted an angiotensin II- or phenylephrine-induced hypertrophic response in isolated cardiomyocytes. Mechanistically, TRAF3 directly bound to TANK-binding kinase 1 (TBK1), causing increased TBK1 phosphorylation in response to hypertrophic stimuli. This interaction between TRAF3 and TBK1 further activated AKT signaling, which ultimately promoted the development of cardiac hypertrophy. Our findings not only reveal a key role of TRAF3 in regulating the hypertrophic response but also uncover TRAF3-TBK1-AKT as a novel signaling pathway in the development of cardiac hypertrophy and heart failure. This pathway may represent a potential therapeutic target for this pathological process.


Assuntos
Cardiomegalia/patologia , Cardiomegalia/fisiopatologia , Transdução de Sinais/fisiologia , Fator 3 Associado a Receptor de TNF/fisiologia , Regulação para Cima/fisiologia , Angiotensina II/farmacologia , Animais , Modelos Animais de Doenças , Feminino , Humanos , Hipertrofia , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Fenilefrina/farmacologia , Fosforilação/fisiologia , Proteínas Serina-Treonina Quinases/fisiologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Fator 3 Associado a Receptor de TNF/deficiência , Fator 3 Associado a Receptor de TNF/genética
11.
Hypertension ; 66(3): 571-81, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26101343

RESUMO

The adaptor protein Src homology 2-B3 (SH2B3), which belongs to a subfamily of Src homology 2 proteins, is a broad inhibitor of growth factors and cytokine signaling in hematopoietic cells. However, the role of SH2B3 in nonhematopoietic systems, particularly cardiomyocytes, has not been defined. In this study, we observed noticeable increase in SH2B3 protein expression during pathological cardiac remodeling in both humans and rodents. Follow-up in vitro gain- and loss-of-function studies suggested that SH2B3 promotes the cardiomyocyte hypertrophy response. Consistent with the cell phenotype, SH2B3 knockout (SH2B3(-/-)) mice exhibited attenuated cardiac remodeling with preserved cardiac function after chronic pressure overload. Conversely, cardiac-specific SH2B3 overexpression aggravated pressure overload-triggered cardiac hypertrophy, fibrosis, and dysfunction. Mechanistically, SH2B3 accelerates and exacerbates cardiac remodeling through the activation of focal adhesion kinase, which, in turn, activates the prohypertrophic downstream phosphoinositide 3-kinase-AKT-mammalian target of rapamycin/glycogen synthase kinase 3ß signaling pathway. Finally, we generated a novel SH2B3 knockout rat line and further confirmed the protective effects of SH2B3 deficiency on cardiac remodeling across species. Collectively, our data indicate that SH2B3 functions as a novel and effective modulator of cardiac remodeling and failure.


Assuntos
Pressão Sanguínea/fisiologia , Cardiomegalia/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Animais , Cardiomegalia/genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas de Membrana , Camundongos , Camundongos Knockout , Ratos , Transdução de Sinais/fisiologia
12.
Mol Cell Biol ; 34(20): 3867-79, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25135475

RESUMO

HOX cluster genes are activated sequentially in their positional order along the chromosome during vertebrate development. This phenomenon, known as temporal colinearity, depends on transcriptional silencing of 5' HOX genes. Chromatin looping was recently identified as a conserved feature of silent HOX clusters, with CCCTC-binding factor (CTCF) binding sites located at the loop bases. However, the potential contribution of CTCF to HOX cluster silencing and the underlying mechanism have not been established. Here, we demonstrate that the HOXA locus is organized by CTCF into chromatin loops and that CTCF depletion causes significantly enhanced activation of HOXA3 to -A7, -A9 to -A11, and -A13 in response to retinoic acid, with the highest effect observed for HOXA9. Our subsequent analyses revealed that CTCF facilitates the stabilization of Polycomb repressive complex 2 (PRC2) and trimethylated lysine 27 of histone H3 (H3K27me3) at the human HOXA locus. Our results reveal that CTCF functions as a controller of HOXA cluster silencing and mediates PRC2-repressive higher-order chromatin structure.


Assuntos
Cromatina/genética , Inativação Gênica , Proteínas de Homeodomínio/genética , Complexo Repressor Polycomb 2/fisiologia , Proteínas Repressoras/fisiologia , Sequência de Bases , Fator de Ligação a CCCTC , Linhagem Celular Tumoral , Cromatina/metabolismo , Loci Gênicos , Histonas/metabolismo , Proteínas de Homeodomínio/metabolismo , Proteínas de Homeodomínio/ultraestrutura , Humanos , Conformação Molecular , Estabilidade Proteica , Deleção de Sequência , Tretinoína/fisiologia
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