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1.
Nat Commun ; 12(1): 2346, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33879767

RESUMO

Cancer expression of PD-L1 suppresses anti-tumor immunity. PD-L1 has emerged as a remarkable therapeutic target. However, the regulation of PD-L1 degradation is not understood. Here, we identify several compounds as inducers of PD-L1 degradation using a high-throughput drug screen. We find EGFR inhibitors promote PD-L1 ubiquitination and proteasomal degradation following GSK3α-mediated phosphorylation of Ser279/Ser283. We identify ARIH1 as the E3 ubiquitin ligase responsible for targeting PD-L1 to degradation. Overexpression of ARIH1 suppresses tumor growth and promotes cytotoxic T cell activation in wild-type, but not in immunocompromised mice, highlighting the role of ARIH1 in anti-tumor immunity. Moreover, combining EGFR inhibitor ES-072 with anti-CTLA4 immunotherapy results in an additive effect on both tumor growth and cytotoxic T cell activation. Our results delineate a mechanism of PD-L1 degradation and cancer escape from immunity via EGFR-GSK3α-ARIH1 signaling and suggest GSK3α and ARIH1 might be potential drug targets to boost anti-tumor immunity and enhance immunotherapies.


Assuntos
Antígeno B7-H1/metabolismo , Neoplasias/imunologia , Neoplasias/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Antígeno B7-H1/química , Antígeno CTLA-4/antagonistas & inibidores , Ensaios de Seleção de Medicamentos Antitumorais , Receptores ErbB/antagonistas & inibidores , Feminino , Quinase 3 da Glicogênio Sintase/metabolismo , Células HEK293 , Ensaios de Triagem em Larga Escala , Humanos , Imunoterapia/métodos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Modelos Biológicos , Neoplasias/terapia , Fosforilação , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Transdução de Sinais , Linfócitos T Citotóxicos/efeitos dos fármacos , Linfócitos T Citotóxicos/imunologia , Evasão Tumoral/fisiologia , Células U937 , Ubiquitinação/efeitos dos fármacos
2.
Cells ; 10(2)2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33525562

RESUMO

Lithium salts have been in the therapeutic toolbox for better or worse since the 19th century, with purported benefit in gout, hangover, insomnia, and early suggestions that lithium improved psychiatric disorders. However, the remarkable effects of lithium reported by John Cade and subsequently by Mogens Schou revolutionized the treatment of bipolar disorder. The known molecular targets of lithium are surprisingly few and include the signaling kinase glycogen synthase kinase-3 (GSK-3), a group of structurally related phosphomonoesterases that includes inositol monophosphatases, and phosphoglucomutase. Here we present a brief history of the therapeutic uses of lithium and then focus on GSK-3 as a therapeutic target in diverse diseases, including bipolar disorder, cancer, and coronavirus infections.


Assuntos
Antimaníacos/uso terapêutico , Transtorno Bipolar/tratamento farmacológico , Compostos de Lítio/uso terapêutico , Neoplasias/tratamento farmacológico , Doenças Neurodegenerativas/tratamento farmacológico , Síndrome Respiratória Aguda Grave/tratamento farmacológico , Animais , Antimaníacos/farmacologia , Transtorno Bipolar/metabolismo , Coronavirus/efeitos dos fármacos , Quinase 3 da Glicogênio Sintase/metabolismo , Humanos , Compostos de Lítio/farmacologia , Neoplasias/metabolismo , Doenças Neurodegenerativas/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Síndrome Respiratória Aguda Grave/metabolismo , Transdução de Sinais/efeitos dos fármacos
3.
Phytomedicine ; 83: 153473, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33513558

RESUMO

BACKGROUND: Diabetes mellitus is a chronic metabolic disease characterized by increased blood glucose levels. In order to lower blood glucose, it is important to stimulate glucose uptake and glycogen synthesis in the muscle. (E)-5-hydroxy-7-methoxy-3-(2'-hydroxybenzyl)-4-chromanone (HM-chromanone), a constituent isolated from Portulaca oleracea L., exhibits anti-diabetic effects; however, its mechanisms are not yet clearly understood on glucose uptake and glycogen synthesis in muscle cells. PURPOSE: In the present study, we examined the effects of HM-chromanone on glucose uptake into L6 skeletal muscle cells and elucidated the underlying mechanisms. METHODS: The effects of HM-chromanone on glucose uptake into L6 skeletal muscle cells were assessed by 2-Deoxyglucose uptake assay. Western blot analysis was carried out to elucidate the underlying molecular mechanisms. RESULTS: We found that HM-chromanone promoted glucose uptake into L6 skeletal muscle cells in a dose-dependent manner. Moreover, HM-chromanone induced the phosphorylation of IRS-1Tyr612 and AKTSer473, and the activation of PI3K. HM-chromanone also stimulated the phosphorylation of AMPKThr172, AS160Thr642, TBC1D1Ser237, and ACC via the CaMKKß pathway. Furthermore, HM-chromanone increased glycogen synthesis through the inactivation of glycogen synthase kinase 3 α/ß. CONCLUSION: The results of this study indicate that HM-chromanone stimulates glucose uptake through the activation of the PI3K/AKT and CaMKKß-AMPK pathways and glycogen synthesis via the GSK3 α/ß pathway in L6 skeletal muscle cells.


Assuntos
Flavonoides/farmacologia , Glucose/metabolismo , Glicogênio/biossíntese , Músculo Esquelético/efeitos dos fármacos , Portulaca/química , Animais , Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina/metabolismo , Células Cultivadas , Desoxiglucose/metabolismo , Glicogênio/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Músculo Esquelético/citologia , Músculo Esquelético/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos
4.
Int J Mol Sci ; 22(1)2020 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-33375448

RESUMO

Lithium is the prototype mood-stabilizer used for acute and long-term treatment of bipolar disorder. Cumulated translational research of lithium indicated the drug's neuroprotective characteristics and, thereby, has raised the option of repurposing it as a drug for neurodegenerative diseases. Lithium's neuroprotective properties rely on its modulation of homeostatic mechanisms such as inflammation, mitochondrial function, oxidative stress, autophagy, and apoptosis. This myriad of intracellular responses are, possibly, consequences of the drug's inhibition of the enzymes inositol-monophosphatase (IMPase) and glycogen-synthase-kinase (GSK)-3. Here we review lithium's neurobiological properties as evidenced by its neurotrophic and neuroprotective properties, as well as translational studies in cells in culture, in animal models of Alzheimer's disease (AD) and in patients, discussing the rationale for the drug's use in the treatment of AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Autofagia/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Lítio/uso terapêutico , Fármacos Neuroprotetores/farmacologia , Animais , Apoptose/efeitos dos fármacos , Transtorno Bipolar/tratamento farmacológico , Reposicionamento de Medicamentos , Quinase 3 da Glicogênio Sintase/metabolismo , Humanos , Lítio/farmacologia , Lítio/toxicidade , Doenças Neurodegenerativas/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Monoéster Fosfórico Hidrolases/metabolismo
5.
PLoS One ; 15(7): e0224952, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32692785

RESUMO

Tauopathies are a class of neurodegenerative disorders characterized by abnormal deposition of post-translationally modified tau protein in the human brain. Tauopathies are associated with Alzheimer's disease (AD), chronic traumatic encephalopathy (CTE), and other diseases. Hyperphosphorylation increases tau tendency to aggregate and form neurofibrillary tangles (NFT), a pathological hallmark of AD. In this study, okadaic acid (OA, 100 nM), a protein phosphatase 1/2A inhibitor, was treated for 24h in mouse neuroblastoma (N2a) and differentiated rat primary neuronal cortical cell cultures (CTX) to induce tau-hyperphosphorylation and oligomerization as a cell-based tauopathy model. Following the treatments, the effectiveness of different kinase inhibitors was assessed using the tauopathy-relevant tau antibodies through tau-immunoblotting, including the sites: pSer202/pThr205 (AT8), pThr181 (AT270), pSer202 (CP13), pSer396/pSer404 (PHF-1), and pThr231 (RZ3). OA-treated samples induced tau phosphorylation and oligomerization at all tested epitopes, forming a monomeric band (46-67 kDa) and oligomeric bands (170 kDa and 240 kDa). We found that TBB (a casein kinase II inhibitor), AR and LiCl (GSK-3 inhibitors), cyclosporin A (calcineurin inhibitor), and Saracatinib (Fyn kinase inhibitor) caused robust inhibition of OA-induced monomeric and oligomeric p-tau in both N2a and CTX culture. Additionally, a cyclin-dependent kinase 5 inhibitor (Roscovitine) and a calcium chelator (EGTA) showed contrasting results between the two neuronal cultures. This study provides a comprehensive view of potential drug candidates (TBB, CsA, AR, and Saracatinib), and their efficacy against tau hyperphosphorylation and oligomerization processes. These findings warrant further experimentation, possibly including animal models of tauopathies, which may provide a putative Neurotherapy for AD, CTE, and other forms of tauopathy-induced neurodegenerative diseases.


Assuntos
Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Ácido Okadáico/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Multimerização Proteica/efeitos dos fármacos , Animais , Linhagem Celular , Ciclosporina/farmacologia , Quinase 3 da Glicogênio Sintase/metabolismo , Cloreto de Lítio/farmacologia , Camundongos , Modelos Biológicos , Fosforilação/efeitos dos fármacos , Ratos , Tauopatias/metabolismo , Tauopatias/patologia , Triazóis/farmacologia
6.
Nat Biomed Eng ; 4(9): 889-900, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32661320

RESUMO

Study of the molecular basis of myocardial fibrosis is hampered by limited access to tissues from human patients and by confounding variables associated with sample accessibility, collection, processing and storage. Here, we report an integrative strategy based on mass spectrometry for the phosphoproteomic profiling of normal and fibrotic cardiac tissue obtained from surgical explants from patients with hypertrophic cardiomyopathy, from a transaortic-constriction mouse model of cardiac hypertrophy and fibrosis, and from a heart-on-a-chip model of cardiac fibrosis. We used the integrative approach to map the relative abundance of thousands of proteins, phosphoproteins and phosphorylation sites specific to each tissue source, to identify key signalling pathways driving fibrosis and to screen for anti-fibrotic compounds targeting glycogen synthase kinase 3, which has a consistent role as a key mediator of fibrosis in all three types of tissue specimen. The integrative disease-modelling strategy may reveal new insights into mechanisms of cardiac disease and serve as a test bed for drug screening.


Assuntos
Miocárdio/patologia , Proteômica/métodos , Transdução de Sinais , Animais , Cardiomiopatia Hipertrófica/metabolismo , Cardiomiopatia Hipertrófica/patologia , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Fibrose , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Quinase 3 da Glicogênio Sintase/metabolismo , Humanos , Camundongos , Miocárdio/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Fosfoproteínas/metabolismo , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Proteoma/metabolismo , Engenharia Tecidual
7.
Nat Commun ; 11(1): 3147, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32561720

RESUMO

Transposons are known to participate in tissue aging, but their effects on aged stem cells remain unclear. Here, we report that in the Drosophila ovarian germline stem cell (GSC) niche, aging-related reductions in expression of Piwi (a transposon silencer) derepress retrotransposons and cause GSC loss. Suppression of Piwi expression in the young niche mimics the aged niche, causing retrotransposon depression and coincident activation of Toll-mediated signaling, which promotes Glycogen synthase kinase 3 activity to degrade ß-catenin. Disruption of ß-catenin-E-cadherin-mediated GSC anchorage then results in GSC loss. Knocking down gypsy (a highly active retrotransposon) or toll, or inhibiting reverse transcription in the piwi-deficient niche, suppresses GSK3 activity and ß-catenin degradation, restoring GSC-niche attachment. This retrotransposon-mediated impairment of aged stem cell maintenance may have relevance in many tissues, and could represent a viable therapeutic target for aging-related tissue degeneration.


Assuntos
Proteínas Argonauta/metabolismo , Senescência Celular , Proteínas de Drosophila/metabolismo , Drosophila melanogaster , Células Germinativas/metabolismo , Animais , Proteínas Argonauta/genética , Caderinas/metabolismo , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Feminino , Inativação Gênica , Quinase 3 da Glicogênio Sintase/metabolismo , Ovário/citologia , Ovário/metabolismo , Retroelementos/genética , Transdução de Sinais , Nicho de Células-Tronco/fisiologia , Células-Tronco/metabolismo , Receptores Toll-Like/metabolismo , beta Catenina/metabolismo
8.
Life Sci ; 256: 117983, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32565252

RESUMO

Estrogen receptor (ER) positive accounts for a large proportion of breast cancer. Although there are many targeted therapeutic drugs, the emergence of drug resistance urgently requires the development of new drugs. Arctigenin (Arc), a lignan found in certain plants of the Asteraceae, has the effect on inhibiting breast cancer, but its molecular mechanism has not been clear. AIMS: To this end, the current study focuses on understanding the mechanism of Arc on ER-positive breast cancer cells. MAIN METHODS: Colony formation experiments and sulforhodamine B methods were used to determine the growth-inhibitory effect of Arc. The cell cycle and apoptosis were analyzed by flow cytometry. Alterations of signaling proteins were measured by Western blotting. Protein degradation was determined by comparing protein half-lives and inhibiting proteasome. KEY FINDINGS: The experimental results show that Arc did not induce apoptosis in ER-positive breast cancer cell, rather caused G1 cycle arrest by decreasing cyclin D1 levels without effect on altering CDK4/6 levels. Moreover, we have demonstrated that Arc decreases cyclin D1 levels through prompting Akt/GSK3ß-mediated degradation. SIGNIFICANCE: These findings warrant the potential of Arc as a candidate treatment for ER-positive breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Pontos de Checagem do Ciclo Celular/fisiologia , Ciclina D1/metabolismo , Furanos/farmacologia , Quinase 3 da Glicogênio Sintase/metabolismo , Lignanas/farmacologia , Receptores Estrogênicos/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Relação Dose-Resposta a Droga , Feminino , Furanos/uso terapêutico , Humanos , Lignanas/uso terapêutico , Células MCF-7 , Proteólise/efeitos dos fármacos
9.
Proc Natl Acad Sci U S A ; 117(20): 11085-11096, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32358191

RESUMO

Glioblastoma (GBM) is the deadliest adult brain cancer, and all patients ultimately succumb to the disease. Radiation therapy (RT) provides survival benefit of 6 mo over surgery alone, but these results have not improved in decades. We report that radiation induces a glioma-initiating cell phenotype, and we have identified trifluoperazine (TFP) as a compound that interferes with this phenotype conversion. TFP causes loss of radiation-induced Nanog mRNA expression, and activation of GSK3 with consecutive posttranslational reduction in p-Akt, Sox2, and ß-catenin protein levels. TFP did not alter the intrinsic radiation sensitivity of glioma-initiating cells (GICs). Continuous treatment with TFP and a single dose of radiation reduced the number of GICs in vivo and prolonged survival in syngeneic and patient-derived orthotopic xenograft (PDOX) mouse models of GBM. Our findings suggest that the combination of a dopamine receptor antagonist with radiation enhances the efficacy of RT in GBM by preventing radiation-induced phenotype conversion of radiosensitive non-GICs into treatment-resistant, induced GICs (iGICs).


Assuntos
Antagonistas de Dopamina/farmacologia , Glioblastoma/metabolismo , Fenótipo , Receptores Dopaminérgicos/efeitos dos fármacos , Trifluoperazina/farmacologia , Animais , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/radioterapia , Modelos Animais de Doenças , Antagonistas de Dopamina/uso terapêutico , Regulação Neoplásica da Expressão Gênica , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Glioblastoma/radioterapia , Glioma/tratamento farmacológico , Glioma/metabolismo , Glioma/patologia , Glioma/radioterapia , Quinase 3 da Glicogênio Sintase/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos SCID , RNA Mensageiro/metabolismo , Tolerância a Radiação , Fatores de Transcrição SOXB1 , Trifluoperazina/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto , beta Catenina
10.
Nucleic Acids Res ; 48(11): 6068-6080, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32374842

RESUMO

We have previously found that UV-induced DNA damage causes hyperphosphorylation of the carboxy terminal domain (CTD) of RNA polymerase II (RNAPII), inhibition of transcriptional elongation and changes in alternative splicing (AS) due to kinetic coupling between transcription and splicing. In an unbiased search for protein kinases involved in the AS response to DNA damage, we have identified glycogen synthase kinase 3 (GSK-3) as an unforeseen participant. Unlike Cdk9 inhibition, GSK-3 inhibition only prevents CTD hyperphosphorylation triggered by UV but not basal phosphorylation. This effect is not due to differential degradation of the phospho-CTD isoforms and can be reproduced, at the AS level, by overexpression of a kinase-dead GSK-3 dominant negative mutant. GSK-3 inhibition abrogates both the reduction in RNAPII elongation and changes in AS elicited by UV. We show that GSK-3 phosphorylates the CTD in vitro, but preferentially when the substrate is previously phosphorylated, consistently with the requirement of a priming phosphorylation reported for GSK-3 efficacy. In line with a role for GSK-3 in the response to DNA damage, GSK-3 inhibition prevents UV-induced apoptosis. In summary, we uncover a novel role for a widely studied kinase in key steps of eukaryotic transcription and pre-mRNA processing.


Assuntos
Quinase 3 da Glicogênio Sintase/metabolismo , Proteínas Quinases/metabolismo , RNA Polimerase II/química , RNA Polimerase II/metabolismo , Processamento Alternativo/genética , Processamento Alternativo/efeitos da radiação , Apoptose/efeitos da radiação , Dano ao DNA/efeitos da radiação , Fluorescência , Genes Dominantes , Genes Reporter , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Quinase 3 da Glicogênio Sintase/genética , Células HEK293 , Células HeLa , Histonas/metabolismo , Humanos , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Fosforilação/efeitos da radiação , Proteínas Quinases/genética , Transcrição Genética/efeitos da radiação , Raios Ultravioleta
11.
Nat Commun ; 11(1): 1617, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32238817

RESUMO

Translational control plays a central role in regulation of gene expression and can lead to significant divergence between mRNA- and protein-abundance. Here, we used genome-wide approaches combined with time-course analysis to measure the mRNA-abundance, mRNA-translation rate and protein expression during the transition of naïve-to-primed mouse embryonic stem cells (ESCs). We find that the ground state ESCs cultured with GSK3-, MEK-inhibitors and LIF (2iL) display higher ribosome density on a selective set of mRNAs. This set of mRNAs undergo strong translational buffering to maintain stable protein expression levels in 2iL-ESCs. Importantly, we show that the global alteration of cellular proteome during the transition of naïve-to-primed pluripotency is largely accompanied by transcriptional rewiring. Thus, we provide a comprehensive and detailed overview of the global changes in gene expression in different states of ESCs and dissect the relative contributions of mRNA-transcription, translation and regulation of protein stability in controlling protein abundance.


Assuntos
Células-Tronco Embrionárias/metabolismo , Polirribossomos/metabolismo , Proteoma/metabolismo , RNA Mensageiro/metabolismo , Ribossomos/metabolismo , Animais , Regulação da Expressão Gênica , Quinase 3 da Glicogênio Sintase/metabolismo , Redes e Vias Metabólicas , Camundongos , Células-Tronco Embrionárias Murinas/metabolismo , Polirribossomos/genética , Ribossomos/genética , Transcriptoma
12.
Nat Commun ; 11(1): 1635, 2020 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-32242018

RESUMO

It remains unclear why many patients with depression do not respond to antidepressant treatment. In three cohorts of individuals with depression and treated with serotonin-norepinephrine reuptake inhibitor (N = 424) we show that responders, but not non-responders, display an increase of GPR56 mRNA in the blood. In a small group of subjects we also show that GPR56 is downregulated in the PFC of individuals with depression that died by suicide. In mice, we show that chronic stress-induced Gpr56 downregulation in the blood and prefrontal cortex (PFC), which is accompanied by depression-like behavior, and can be reversed by antidepressant treatment. Gpr56 knockdown in mouse PFC is associated with depressive-like behaviors, executive dysfunction and poor response to antidepressant treatment. GPR56 peptide agonists have antidepressant-like effects and upregulated AKT/GSK3/EIF4 pathways. Our findings uncover a potential role of GPR56 in antidepressant response.


Assuntos
Antidepressivos/administração & dosagem , Transtorno Depressivo Maior/tratamento farmacológico , Receptores Acoplados a Proteínas-G/metabolismo , Adulto , Animais , Estudos de Coortes , Transtorno Depressivo Maior/genética , Transtorno Depressivo Maior/metabolismo , Feminino , Quinase 3 da Glicogênio Sintase/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Receptores Acoplados a Proteínas-G/genética , Inibidores de Captação de Serotonina/administração & dosagem , Resultado do Tratamento
13.
Oncol Res ; 28(4): 423-438, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32331534

RESUMO

Although oxaliplatin serves as one of the first-line drugs prescribed for treating colorectal cancer (CRC), the therapeutic effect is disappointing due to drug resistance. So far, the molecular mechanisms mediating oxaliplatin resistance remain unclear. In this study, we found the chemoresistance in oxaliplatin-resistant HCT116 cells (HCT116/OXA) was mediated by the upregulation of ERCC1 expression. In addition, the acquisition of resistance induced epithelialmesenchymal transition (EMT) as well as the Slug overexpression. On the contrary, Slug silencing reversed the EMT phenotype, decreased ERCC1 expression, and ameliorated drug resistance. Further mechanistical studies revealed the enhanced Slug expression resulted from the activation of AKT/glycogen synthase kinase 3 (GSK3) signaling. Moreover, in CRC patients, coexpression of Slug and ERCC1 was observed, and increased Slug expression was significantly correlated with clinicopathological factors and prognosis. Taken together, the simultaneous inhibition of the AKT/GSK3/Slug axis may be of significance for surmounting metastasis and chemoresistance, thereby improving the therapeutic outcome of oxaliplatin.


Assuntos
Neoplasias Colorretais/metabolismo , Proteínas de Ligação a DNA/metabolismo , Endonucleases/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Oxaliplatina/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fatores de Transcrição da Família Snail/metabolismo , Antineoplásicos/farmacologia , Movimento Celular/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Proteínas de Ligação a DNA/genética , Resistencia a Medicamentos Antineoplásicos , Endonucleases/genética , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Quinase 3 da Glicogênio Sintase/genética , Células HCT116 , Humanos , Fenótipo , Proteínas Proto-Oncogênicas c-akt/genética , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição da Família Snail/genética , Regulação para Cima/efeitos dos fármacos
14.
Gene ; 749: 144707, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32344005

RESUMO

ANGPTL8 is a 22-KDa protein in the angiopoietin-like family. It is a liver-derived hormone that dynamically regulates glucose metabolism after refeeding. The mechanism of its regulation of glucose metabolism is unclear. We analyzed the effect of ANGPTL8 overexpression on glucose tolerance in the mouse liver by tail vein hydrodynamic transfection. The mechanism of ANGPTL8 improving insulin sensitivity was analyzed by the overexpression or knockdown of ANGPTL8 in mouse primary hepatocytes through in vitro synthetic mRNA and siRNA technology. The key site of ANGPTL8 protein regulating this signal pathway was screened by DNA point mutation and fragment truncation. The results showed that ANGPTL8 may directly regulate AKT protein phosphorylation in the insulin-mediated PI3K/AKT signaling pathway to improve insulin sensitivity. Ser94 and Thr98 are the key sites of ANGPTL8 protein in activating AKT protein phosphorylation. Present results indicate that ANGPTL8 may be a potential new agent to reduce postprandial blood glucose.


Assuntos
Proteínas Semelhantes a Angiopoietina/metabolismo , Resistência à Insulina , Insulina/fisiologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Fatores de Transcrição Forkhead/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Células Hep G2 , Hepatócitos/enzimologia , Hepatócitos/metabolismo , Humanos , Masculino , Camundongos Endogâmicos C57BL , Hormônios Peptídicos/metabolismo , Transdução de Sinais , Ganho de Peso
15.
Neurobiol Aging ; 90: 93-98, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32169355

RESUMO

Partitioning-defective 1 (PAR-1), a conserved cell polarity regulator, plays an important role in synaptic development, and its mutation affects the formation of synaptic boutons and localization of postsynaptic density protein Discs large (Dlg) at the neuromuscular junction (NMJ) in Drosophila. Drosophila PAR-1 and its human homolog, Microtubule affinity-regulating kinases (MARK), are also known to be implicated in Alzheimer's disease (AD) by controlling tau-mediated Aß toxicity. However, the molecular mechanisms of PAR-1 function remain incompletely understood. Here we identified Pod-1, an actin-microtubule crosslinker, which functionally and physically interacts with PAR-1 in Drosophila. Pod-1 prominently co-localizes with PAR-1 in the postsynaptic region and regulates PAR-1 activity at the NMJ. Synaptic defects, including the reduction of boutons and delocalization of Dlg caused by PAR-1 overexpression, were rescued by Pod-1 knockdown. Conversely, the reduction of synaptic boutons in PAR-1 overexpressed NMJ was synergistically enhanced by the overexpression of Pod-1. Furthermore, Pod-1 increases the PAR-1 dependent S262 phosphorylation of tau, which is known to contribute to tau-mediated Aß toxicity. In line with the change of tau phosphorylation, Pod-1 knockdown rescued tau-mediated synaptic toxicity at the NMJ. Our results suggest that Pod-1 may act as a modulator of PAR-1 in synaptic development and tau-mediated toxicity.


Assuntos
Peptídeos beta-Amiloides/toxicidade , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/fisiologia , Regulação da Expressão Gênica no Desenvolvimento/genética , Expressão Gênica , Quinase 3 da Glicogênio Sintase/metabolismo , Quinase 3 da Glicogênio Sintase/fisiologia , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Sinapses/metabolismo , Sinapses/fisiologia , Proteínas tau/metabolismo , Animais , Drosophila , Proteínas de Drosophila/genética , Epistasia Genética , Quinase 3 da Glicogênio Sintase/genética , Junção Neuromuscular/metabolismo , Fosforilação/genética
16.
Food Chem Toxicol ; 138: 111252, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32156565

RESUMO

The brain is a highly metabolic organ and requires regulatory mechanisms to meet its high energy demand, with the PI3K/Akt and AMPK signalling pathways being central regulators of cellular energy and metabolism, also making them major targets for the development of neurometabolic disorders. Fusaric acid (FA), a toxin of fungal origin, was found to be a potent hypotensive agent in vivo and in clinical trials by altering brain neurochemistry thus demonstrating its neurological effects. Notably, FA is a putative mitochondrial toxin, however, the metabolic effects of FA in the brain remains unknown. Therefore, this study investigates the neurometabolic effects of FA via alterations to Akt and AMPK signalling pathways in C57BL/6 mice at acute (1 day) and prolonged exposure (10 days). Following 1 day exposure, FA augmented Akt signalling by increasing Akt S473 phosphorylation and the upstream regulators PI3K, mTOR and p70S6K. Activated Akt showed inhibition of GSK3 activity with the simultaneous activation of AMPK, p53 phosphorylation and reduced GLUT-1 and -4 receptor expressions, potentially suppressing neuronal glucose entry. However, after 10 days exposure, FA dampened PI3K/Akt and AMPK signalling, but increased the expression of GLUT receptors (1 and 4) in mice brain. Further, FA significantly depleted ATP levels, at 10 days exposure, despite increased PDHE1ß activity (at both 1 and 10 days), strongly suggesting that FA mediates ATP depletion independent of metabolic signalling. In conclusion, FA mediates neurometabolic disturbances, at 1 and 10 day exposures, which may negatively influence normal brain aging and predispose to neurodegenerative disorders.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Ácido Fusárico/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Encéfalo/metabolismo , Transportador de Glucose Tipo 4/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fosfatidilinositol 3-Quinases/metabolismo , Receptores de Superfície Celular/metabolismo , Serina-Treonina Quinases TOR/metabolismo
17.
Apunts, Med. esport (Internet) ; 55(205): 21-27, ene.-mar. 2020. tab, graf
Artigo em Inglês | IBECS | ID: ibc-192334

RESUMO

INTRODUCTION: The present study was to determine the effect of 8-week of the concurrent exercise training on Murf-l and Atrogin-1 Gene Expression of the vastus lateralis muscle in male Wistar rats. MATERIAL AND METHODS: This study was conducted as an experimental project consisting of four groups of 35 two-month-old male Wistar rats. The animals were randomly divided in 4 groups: (1) endurance training, (2) resistance training, (3) combined training, and (4) control. The animals in the training groups took part in training programs for 8-week. 48h after the last exercise session, the Murf-1 and Atrogin-1 genes of the vastus lateralis muscle were examined through the use of qPCR method. RESULTS: The results obtained from this study revealed that after 8-week of endurance exercise, Murf-1 and Arogin-1 gene expression significantly increased compared to the control group (p = 0.04 and p = 0.043). In contrast, in the resistance training group, the gene expression of Murf-1 and Atrogin-1 decreased significantly in comparison with the control group (p = 0.02 and p = 0.04). In addition, the concurrent training group showed no difference in Murf-1 and Atrogin-1 gene expression after 8-week of exercise compared to that of the control group (p = 0.43 and p = 0.38). CONCLUSIONS: Based on the results of the present research, it can be expressed that resistance training prevents muscular atrophy by decreasing Murf-1 and Atrogin-1 gene expression. Conversely, endurance exercises cause an increase in the expression of these genes, thereby leading to atrophy in the muscles. The results also showed that concurrent exercises do not have a meaningful effect on muscular atrophy


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Assuntos
Animais , Masculino , Ratos , Expressão Gênica/fisiologia , Quinase 3 da Glicogênio Sintase/metabolismo , Proteínas Musculares/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Proteínas Musculares/efeitos dos fármacos , Condicionamento Físico Animal , Ratos Wistar , Resistência Física/efeitos dos fármacos
18.
Environ Toxicol ; 35(7): 727-737, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32073747

RESUMO

Our previous work indicated exposure of Human liver cell 7702 (HL7702) cells to Microcystin-leucine-arginine (MC-LR) for 24 hours can disrupt insulin (INS) signaling by the hyperphosphorylation of specific proteins. For further exploring the time-dependent effect posed by MC-LR on this pathway, in the current study, HL7702 cells together with mice were exposed to the MC-LR with different concentrations under short-term treatment, and then, protein phosphatase 2A (PP2A) activity and expression of proteins related to INS signaling, as well as the characteristics of their action in the liver, were investigated. The results indicated, in HL7702 cells with 0.5, 1, and 6 hours of treatment by MC-LR, PP2A activity showed an obvious decrease in a time and concentration-dependent manner. While the total protein level of Akt, glycogen synthase kinase 3 (GSK-3), and glycogen synthase remained unchanged, GSK-3 and Akt phosphorylation increased significantly. In livers of mice with 1 hour of intraperitoneal injection with MC-LR, a similar change in these proteins was observed. In addition, the levels of total IRS1 and p-IRS1 at serine sites showed decreasing and increasing trends,respectively, and the hematoxylin and eosin staining showed that liver tissues of mice in the maximum-dose group exhibited obvious hepatocyte degeneration and hemorrhage. Our results further proved that short-term treatment with MC-LR can inhibit PP2A activity and disrupt INS signaling proteins' phosphorylation level, thereby interfering with the INS pathway. Our findings provide a helpful understanding of the toxic effects posed by MC-LR on the glucose metabolism of liver via interference with the INS signaling pathway.


Assuntos
Insulina/metabolismo , Fígado/efeitos dos fármacos , Microcistinas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Linhagem Celular , Relação Dose-Resposta a Droga , Glicogênio Sintase/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Fígado/metabolismo , Fígado/patologia , Masculino , Toxinas Marinhas , Camundongos , Fosforilação/efeitos dos fármacos , Proteína Fosfatase 2/metabolismo , Transdução de Sinais/efeitos dos fármacos
19.
Biochim Biophys Acta Mol Cell Res ; 1867(6): 118679, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32061630

RESUMO

Head and neck squamous cell carcinoma (HNSCC) is a highly morbid, genetically unstable disease derived from the mucoepithelium of the upper aerodigestive tract. Recent characterization of this disease has implicated the PI3K-Akt-mTOR pathway as one of the most frequently dysregulated pathways. As such, there are several classes of PI3K inhibitors currently undergoing clinical trials. In this article, we review the PI3K pathway, mutations of this pathway in HNSCC, drugs that target PI3K, the impact of these agents on the PI3K and GSK-3 signaling axes, ongoing clinical trials evaluating PI3K inhibitors, and the challenges of using these drugs in the clinic. This article is part of a Special Issue entitled: GSK-3 and related kinases in cancer, neurological and other disorders edited by James McCubrey, Agnieszka Gizak and Dariusz Rakus.


Assuntos
Quinase 3 da Glicogênio Sintase/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Ensaios Clínicos como Assunto , Resistencia a Medicamentos Antineoplásicos , Quinase 3 da Glicogênio Sintase/genética , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/genética , Humanos , Mutação , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética
20.
Biol Sex Differ ; 11(1): 8, 2020 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-32087746

RESUMO

Depression and anxiety are more common among females than males and represent a leading cause of disease-related disability in women. Since the dopamine D1-D2 heteromer is involved in depression- and anxiety-like behavior, the possibility that the receptor complex may have a role in mediating sex differences in such behaviors and related biochemical signaling was explored.In non-human primate caudate nucleus and in rat striatum, females expressed higher density of D1-D2 heteromer complexes and a greater number of D1-D2 expressing neurons compared to males. In rat, the sex difference in D1-D2 expression levels occurred even though D1 receptor expression was lower in female than in male with no difference in D2 receptor expression. In behavioral tests, female rats showed faster latency to depressive-like behavior and a greater susceptibility to the pro-depressive and anxiogenic-like effects of D1-D2 heteromer activation by low doses of SKF 83959, all of which were ameliorated by the selective heteromer disrupting peptide, TAT-D1. The sex difference observed in the anxiety test correlated with differences in low-frequency delta and theta oscillations in the nucleus accumbens. Analysis of signaling pathways revealed that the sex difference in D1-D2 heteromer expression led to differences in basal and heteromer-stimulated activities of two important signaling pathways, BDNF/TrkB and Akt/GSK3/ß-catenin.These results suggest that the higher D1-D2 heteromer expression in female may significantly increase predisposition to depressive-like and anxiety-like behavior in female animals.


Assuntos
Ansiedade/metabolismo , Núcleo Caudado/metabolismo , Depressão/metabolismo , Núcleo Accumbens/metabolismo , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/metabolismo , Caracteres Sexuais , Transdução de Sinais , 2,3,4,5-Tetra-Hidro-7,8-Di-Hidroxi-1-Fenil-1H-3-Benzazepina/administração & dosagem , 2,3,4,5-Tetra-Hidro-7,8-Di-Hidroxi-1-Fenil-1H-3-Benzazepina/análogos & derivados , Animais , Ansiedade/fisiopatologia , Comportamento Animal , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Núcleo Caudado/efeitos dos fármacos , Chlorocebus aethiops , Depressão/fisiopatologia , Feminino , Quinase 3 da Glicogênio Sintase/metabolismo , Masculino , Núcleo Accumbens/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Sprague-Dawley , Receptor trkB/metabolismo , Receptores de Dopamina D1/agonistas , Receptores de Dopamina D2/agonistas , Transdução de Sinais/efeitos dos fármacos , beta Catenina/metabolismo
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