Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 32
Filtrar
1.
Int J Mol Sci ; 25(12)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38928510

RESUMO

The decline in the function and mass of skeletal muscle during aging or other pathological conditions increases the incidence of aging-related secondary diseases, ultimately contributing to a decreased lifespan and quality of life. Much effort has been made to surmise the molecular mechanisms underlying muscle atrophy and develop tools for improving muscle function. Enhancing mitochondrial function is considered critical for increasing muscle function and health. This study is aimed at evaluating the effect of an aqueous extract of Gloiopeltis tenax (GTAE) on myogenesis and muscle atrophy caused by dexamethasone (DEX). The GTAE promoted myogenic differentiation, accompanied by an increase in peroxisome proliferator-activated receptor γ coactivator α (PGC-1α) expression and mitochondrial content in myoblast cell culture. In addition, the GTAE alleviated the DEX-mediated myotube atrophy that is attributable to the Akt-mediated inhibition of the Atrogin/MuRF1 pathway. Furthermore, an in vivo study using a DEX-induced muscle atrophy mouse model demonstrated the efficacy of GTAE in protecting muscles from atrophy and enhancing mitochondrial biogenesis and function, even under conditions of atrophy. Taken together, this study suggests that the GTAE shows propitious potential as a nutraceutical for enhancing muscle function and preventing muscle wasting.


Assuntos
Dexametasona , Desenvolvimento Muscular , Atrofia Muscular , Extratos Vegetais , Animais , Atrofia Muscular/induzido quimicamente , Atrofia Muscular/metabolismo , Atrofia Muscular/tratamento farmacológico , Atrofia Muscular/patologia , Dexametasona/efeitos adversos , Dexametasona/farmacologia , Desenvolvimento Muscular/efeitos dos fármacos , Camundongos , Extratos Vegetais/farmacologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Diferenciação Celular/efeitos dos fármacos , Mioblastos/efeitos dos fármacos , Mioblastos/metabolismo , Linhagem Celular , Proteínas Musculares/metabolismo , Masculino , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/patologia , Camundongos Endogâmicos C57BL , Proteínas com Motivo Tripartido/metabolismo , Proteínas com Motivo Tripartido/genética , Rodófitas
2.
Biochem Biophys Res Commun ; 517(3): 484-490, 2019 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-31371025

RESUMO

Obesity that is critically correlated with the initiation and development of metabolic syndrome and cardiovascular diseases has increased worldwide. Adipogenesis is coordinated through multi-steps involving adipogenic commitment, mitotic clonal expansion (MCE) and differentiation. Recently, protein arginine methyltransferase 4 (PRMT4) and PRMT5 have been implicated in modulation of adipogenesis via regulation of C/EBP-ß activity or PPAR-γ2 expression. In the current study, we demonstrate a suppressive role of PRMT7 in adipogenesis. PRMT7-depleted preadipocytes or PRMT7-/- mouse embryonic fibroblasts (MEFs) displayed increased adipogenesis while PRMT7 overexpression attenuated it. PRMT7 depletion in preadipocytes promoted MCE, an initial step of adipogenesis. Furthermore, we found that PRMT7 interacted with and methylated a key adipogenic factor C/EBP-ß upon adipogenic induction and modulated the accumulation of C/EBP-ß at its target sites in the PPAR-γ2 promoter. Taken together, our data suggest that PRMT7 suppresses adipogenesis through modulation of C/EBP-ß activity.


Assuntos
Adipócitos/metabolismo , Adipogenia/genética , Proteína beta Intensificadora de Ligação a CCAAT/genética , PPAR gama/genética , Proteína-Arginina N-Metiltransferases/genética , Células 3T3-L1 , Adipócitos/citologia , Animais , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Diferenciação Celular , Proliferação de Células/genética , Sobrevivência Celular/genética , Fibroblastos/citologia , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Humanos , Metilação , Camundongos , Modelos Biológicos , Obesidade/genética , Obesidade/metabolismo , Obesidade/patologia , PPAR gama/metabolismo , Regiões Promotoras Genéticas , Ligação Proteica , Proteína-Arginina N-Metiltransferases/deficiência , Transdução de Sinais
3.
Proc Natl Acad Sci U S A ; 111(5): 1778-83, 2014 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-24434556

RESUMO

The potential for pluripotent cells to differentiate into diverse specialized cell types has given much hope to the field of regenerative medicine. Nevertheless, the low efficiency of cell commitment has been a major bottleneck in this field. Here we provide a strategy to enhance the efficiency of early differentiation of pluripotent cells. We hypothesized that the initial phase of differentiation can be enhanced if the transcriptional activity of master regulators of stemness is suppressed, blocking the formation of functional transcriptomes. However, an obstacle is the lack of an efficient strategy to block protein-protein interactions. In this work, we take advantage of the biochemical property of seventeen kilodalton protein (Skp), a bacterial molecular chaperone that binds directly to sex determining region Y-box 2 (Sox2). The small angle X-ray scattering analyses provided a low resolution model of the complex and suggested that the transactivation domain of Sox2 is probably wrapped in a cleft on Skp trimer. Upon the transduction of Skp into pluripotent cells, the transcriptional activity of Sox2 was inhibited and the expression of Sox2 and octamer-binding transcription factor 4 was reduced, which resulted in the expression of early differentiation markers and appearance of early neuronal and cardiac progenitors. These results suggest that the initial stage of differentiation can be accelerated by inhibiting master transcription factors of stemness. This strategy can possibly be applied to increase the efficiency of stem cell differentiation into various cell types and also provides a clue to understanding the mechanism of early differentiation.


Assuntos
Diferenciação Celular , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Fatores de Transcrição/metabolismo , Animais , Proteínas de Escherichia coli/metabolismo , Camundongos , Modelos Biológicos , Modelos Moleculares , Fatores de Transcrição SOXB1/metabolismo , Espalhamento a Baixo Ângulo , Soluções , Transdução Genética , Difração de Raios X , Produtos do Gene tat do Vírus da Imunodeficiência Humana/metabolismo
4.
J Mol Cell Cardiol ; 93: 57-66, 2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-26906632

RESUMO

Sonic hedgehog (Shh) signaling plays an important role for early heart development, such as heart looping and cardiomyogenesis of pluripotent stem cells. A multifunctional receptor Cdo functions as a Shh coreceptor together with Boc and Gas1 to activate Shh signaling and these coreceptors seem to play compensatory roles in early heart development. Thus in this study, we examined the role of Cdo in cardiomyogenesis by utilizing an in vitro differentiation of pluripotent stem cells. Here we show that Cdo is required for efficient cardiomyogenesis of pluripotent stem cells by activation of Shh signaling. Cdo is induced concurrently with Shh signaling activation upon induction of cardiomyogenesis of P19 embryonal carcinoma (EC) cells. Cdo-depleted P19 EC and Cdo(-/-) mouse embryonic stem (ES) cells display decreased expression of key cardiac regulators, including Gata4, Nkx2.5 and Mef2c and this decrease coincides with reduced Shh signaling activities. Furthermore Cdo deficiency causes a stark reduction in formation of mature contractile cardiomyocytes. This defect in cardiomyogenesis is overcome by reactivation of Shh signaling at the early specification stage of cardiomyogenesis. The Shh agonist treatment restores differentiation capacities of Cdo-deficient ES cells into contractile cardiomyocytes by recovering both the expression of early cardiac regulators and structural genes such as cardiac troponin T and Connexin 43. Therefore Cdo is required for efficient cardiomyogenesis of pluripotent stem cells and an excellent target to improve the differentiation potential of stem cells for generation of transplantable cells to treat cardiomyopathies.


Assuntos
Moléculas de Adesão Celular/genética , Coração/embriologia , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Organogênese , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Animais , Moléculas de Adesão Celular/metabolismo , Diferenciação Celular , Conexina 43/metabolismo , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Técnicas de Inativação de Genes , Proteínas Hedgehog/agonistas , Proteínas Hedgehog/metabolismo , Camundongos , Contração Miocárdica/genética , Organogênese/genética , Transdução de Sinais
5.
Mol Cell ; 30(1): 98-107, 2008 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-18406330

RESUMO

The LTR-retrotransposon Tf1 preserves the coding capacity of its host Schizosaccharomyces pombe by integrating upstream of open reading frames (ORFs). To determine which features of the target sites were recognized by the transposon, we introduced plasmids containing candidate insertion sites into S. pombe and mapped the positions of integration. We found that Tf1 was targeted specifically to the promoters of Pol II-transcribed genes. A detailed analysis of integration in plasmids that contained either ade6 or fbp1 revealed insertions occurred in the promoters at positions where transcription factors bound. Further experiments revealed that the activator Atf1p and its binding site were required for directing integration to the promoter of fbp1. An interaction between Tf1 integrase and Atf1p was observed, indicating that integration at fbp1 was mediated by the activator bound to its promoter. Surprisingly, we found Tf1 contained sequences that activated transcription, and these substituted for elements of the ade6 promoter disrupted by integration.


Assuntos
Regulação Fúngica da Expressão Gênica , Regiões Promotoras Genéticas , RNA Polimerase II/genética , Retroelementos/genética , Cromatina/química , Cromatina/metabolismo , DNA Intergênico/química , DNA Intergênico/genética , Frutose-Bifosfatase , Conformação de Ácido Nucleico , Fases de Leitura Aberta , Plasmídeos/genética , Plasmídeos/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , RNA Polimerase II/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo , Proteínas de Schizosaccharomyces pombe/genética , Proteínas de Schizosaccharomyces pombe/metabolismo , Transcrição Gênica
6.
Nucleic Acids Res ; 41(2): 775-89, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23193295

RESUMO

Transposable elements possess specific patterns of integration. The biological impact of these integration profiles is not well understood. Tf1, a long-terminal repeat retrotransposon in Schizosaccharomyces pombe, integrates into promoters with a preference for the promoters of stress response genes. To determine the biological significance of Tf1 integration, we took advantage of saturated maps of insertion activity and studied how integration at hot spots affected the expression of the adjacent genes. Our study revealed that Tf1 integration did not reduce gene expression. Importantly, the insertions activated the expression of 6 of 32 genes tested. We found that Tf1 increased gene expression by inserting enhancer activity. Interestingly, the enhancer activity of Tf1 could be limited by Abp1, a host surveillance factor that sequesters transposon sequences into structures containing histone deacetylases. We found the Tf1 promoter was activated by heat treatment and, remarkably, only genes that themselves were induced by heat could be activated by Tf1 integration, suggesting a synergy of Tf1 enhancer sequence with the stress response elements of target promoters. We propose that the integration preference of Tf1 for the promoters of stress response genes and the ability of Tf1 to enhance the expression of these genes co-evolved to promote the survival of cells under stress.


Assuntos
Regulação Fúngica da Expressão Gênica , Resposta ao Choque Térmico/genética , Retroelementos , Elementos Facilitadores Genéticos , Estresse Oxidativo , Regiões Promotoras Genéticas , RNA Helicases/metabolismo , RNA Polimerase II/metabolismo , Schizosaccharomyces/genética , Proteínas de Schizosaccharomyces pombe/metabolismo , Sequências Repetidas Terminais , Transcrição Gênica
7.
BMB Rep ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38627951

RESUMO

Arginine methylation, which is catalyzed by protein arginine methyltransferases (Prmts), is known to play a key role in various biological processes. However, the function of Prmts in osteogenic differentiation of mesenchymal stem cells (MSCs) has not been clearly understood. In the current study, we attempted to elucidate a positive role of Prmt7 in osteogenic differentiation. Prmt7-depleted C3H/10T1/2 cells or bone marrow mesenchymal stem cells (BMSCs) showed the attenuated expression of osteogenic specific genes and Alizarin red staining compared to the wild-type cells. Furthermore, we found that Prmt7 deficiency reduced the activation of bone morphogenetic protein (BMP) signaling cascade, which is essential for the regulation of cell fate commitment and osteogenesis. Taken together, our data indicate that Prmt7 plays important regulatory roles in osteogenic differentiation.

8.
Exp Mol Med ; 56(3): 711-720, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38486105

RESUMO

Protein arginine methyltransferases (PRMTs) modulate diverse cellular processes, including stress responses. The present study explored the role of Prmt7 in protecting against menopause-associated cardiomyopathy. Mice with cardiac-specific Prmt7 ablation (cKO) exhibited sex-specific cardiomyopathy. Male cKO mice exhibited impaired cardiac function, myocardial hypertrophy, and interstitial fibrosis associated with increased oxidative stress. Interestingly, female cKO mice predominantly exhibited comparable phenotypes only after menopause or ovariectomy (OVX). Prmt7 inhibition in cardiomyocytes exacerbated doxorubicin (DOX)-induced oxidative stress and DNA double-strand breaks, along with apoptosis-related protein expression. Treatment with 17ß-estradiol (E2) attenuated the DOX-induced decrease in Prmt7 expression in cardiomyocytes, and Prmt7 depletion abrogated the protective effect of E2 against DOX-induced cardiotoxicity. Transcriptome analysis of ovariectomized wild-type (WT) or cKO hearts and mechanical analysis of Prmt7-deficient cardiomyocytes demonstrated that Prmt7 is required for the control of the JAK/STAT signaling pathway by regulating the expression of suppressor of cytokine signaling 3 (Socs3), which is a negative feedback inhibitor of the JAK/STAT signaling pathway. These data indicate that Prmt7 has a sex-specific cardioprotective effect by regulating the JAK/STAT signaling pathway and, ultimately, may be a potential therapeutic tool for heart failure treatment depending on sex.


Assuntos
Cardiomiopatias , Pós-Menopausa , Proteína-Arginina N-Metiltransferases , Animais , Feminino , Masculino , Camundongos , Apoptose/genética , Cardiomiopatias/genética , Cardiomiopatias/metabolismo , Doxorrubicina/farmacologia , Miócitos Cardíacos/metabolismo , Pós-Menopausa/genética , Transdução de Sinais , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo , Proteína-Arginina N-Metiltransferases/genética , Proteína-Arginina N-Metiltransferases/metabolismo , Janus Quinases/metabolismo , Fatores de Transcrição STAT/metabolismo
9.
J Biol Chem ; 287(15): 11602-15, 2012 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-22337877

RESUMO

p38MAPK plays an essential role in the transition of myoblasts to differentiated myotubes through the activation of MyoD family transcription factors. A promyogenic cell surface molecule, Cdo, promotes myogenic differentiation mainly through activation of the p38MAPK pathway. Two MAP3Ks, TAK1 and ASK1, can activate p38MAPK via MKK6 in various cell systems. Moreover TAK1 has been shown to promote myogenic differentiation via p38MAPK activation. In this study, we hypothesized that TAK1 and ASK1 might function as MAP3Ks in Cdo-mediated p38MAPK activation during myoblast differentiation. Both ASK1 and TAK1 were expressed in myoblasts and interacted with the cytoplasmic tail of Cdo and a scaffold protein, JLP. The depletion of TAK1 or ASK1 in C2C12 cells decreased myoblast differentiation, whereas overexpression of TAK1 or ASK1 in C2C12 cells enhanced myotube formation. In agreement with this, overexpression of ASK1 or TAK1 resulted in enhanced p38MAPK activation, and their knockdown inhibited p38MAPK in C2C12 cells. Overexpression of TAK1 or ASK1 in Cdo(-/-) myoblasts and Cdo-depleted C2C12 cells restored p38MAPK activation as well as myotube formation. Furthermore, ASK1 and TAK1 compensated for each other in p38MAPK activation and myoblast differentiation. Taken together, these findings suggest that ASK1 and TAK1 function as MAP3Ks in Cdo-mediated p38MAPK activation to promote myogenic differentiation.


Assuntos
Moléculas de Adesão Celular/metabolismo , MAP Quinase Quinase Quinase 5/metabolismo , MAP Quinase Quinase Quinases/metabolismo , Sistema de Sinalização das MAP Quinases , Animais , Moléculas de Adesão Celular/genética , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Ativação Enzimática , Técnicas de Inativação de Genes , Humanos , MAP Quinase Quinase Quinase 5/genética , MAP Quinase Quinase Quinases/genética , Camundongos , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo , Desenvolvimento Muscular , Fibras Musculares Esqueléticas/citologia , Fibras Musculares Esqueléticas/metabolismo , Mioblastos/metabolismo , Mioblastos/fisiologia , Ligação Proteica , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
10.
Exp Mol Med ; 55(1): 120-131, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36609601

RESUMO

Osteogenic transdifferentiation of vascular smooth muscle cells (VSMCs) is a risk factor associated with vascular diseases. Wnt signaling is one of the major mechanisms implicated in the osteogenic conversion of VSMCs. Since Cdon has a negative effect on Wnt signaling in distinct cellular processes, we sought to investigate the role of Cdon in vascular calcification. The expression of Cdon was significantly downregulated in VSMCs of the aortas of patients with atherosclerosis and aortic stenosis. Consistently, calcification models, including vitamin D3 (VD3)-injected mice and VSMCs cultured with calcifying media, exhibited reduced Cdon expression. Cdon ablation mice (cKO) exhibited exacerbated aortic stiffness and calcification in response to VD3 compared to the controls. Cdon depletion induced the osteogenic conversion of VSMCs accompanied by cellular senescence. The Cdon-deficient aortas showed a significant alteration in gene expression related to cell proliferation and differentiation together with Wnt signaling regulators. Consistently, Cdon depletion or overexpression in VSMCs elevated or attenuated Wnt-reporter activities, respectively. The deletion mutant of the second immunoglobulin domain (Ig2) in the Cdon ectodomain failed to suppress Wnt signaling and osteogenic conversion of VSMCs. Furthermore, treatment with purified recombinant proteins of the entire ectodomain or Ig2 domain of Cdon displayed suppressive effects on Wnt signaling and VSMC calcification. Our results demonstrate a protective role of Cdon in VSMC calcification by suppressing Wnt signaling. The Ig2 domain of Cdon has the potential as a therapeutic tool to prevent vascular calcification.


Assuntos
Músculo Liso Vascular , Calcificação Vascular , Animais , Camundongos , Moléculas de Adesão Celular/metabolismo , Diferenciação Celular/genética , Células Cultivadas , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Miócitos de Músculo Liso/metabolismo , Osteogênese/genética , Calcificação Vascular/metabolismo , Via de Sinalização Wnt , Humanos
11.
Cell Signal ; 98: 110412, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35863589

RESUMO

Doxorubicin (Dox) is a widely used anti-cancer drug that has a significant limitation, which is cardiotoxicity. Its cardiotoxic side effect is dose dependent and occurs through any age. Dox has been known to exert its toxic effect through oxidative stress, but an emerging mechanism is endoplasmic reticulum (ER) stress that activates proapoptotic pathway involving PERK/ATF4/CHOP axis. These stresses lead to dysfunction of myocardium associated with cell death. Although accumulating evidence support their involvement to Dox-induced cardiotoxicity, the mechanism is not well elucidated. Protein arginine methyltransferases 1 (PRMT1) has been known to play a role in cardiomyocyte cell survival through modulation of ER response. In this study, we demonstrate an important role of PRMT1 in Dox-induced cardiotoxicity via ER stress. Depletion of PRMT1 in H9c2 cardiomyocytes enhanced Dox-stimulated cell death, and increased reactive oxygen species (ROS) production and DNA damage by enhancing the levels of proapoptotic cleaved Caspase-3 and γH2AX in response to Dox. Consistently, overexpression of PRMT1 attenuated the apoptotic effect of Dox. In addition, the acute treatment of Dox induced a substantial increase in PRMT1 activity and the translocation of PRMT1 to ER. Overexpression of PRMT1 in cardiomyocyte diminished Dox-induced ER stress, and ATF4 methylation by PRMT1 was involved in the suppression of ER stress. Taken together, our data suggest that PRMT1 is a novel target molecule for protection from Dox-induced cardiotoxicity.


Assuntos
Cardiotoxicidade , Estresse do Retículo Endoplasmático , Apoptose , Cardiotoxicidade/metabolismo , Cardiotoxicidade/prevenção & controle , Doxorrubicina/toxicidade , Humanos , Metiltransferases/metabolismo , Metiltransferases/farmacologia , Miócitos Cardíacos/metabolismo , Estresse Oxidativo , Proteína-Arginina N-Metiltransferases/genética , Proteína-Arginina N-Metiltransferases/metabolismo , Proteínas Repressoras/metabolismo
12.
J Virol ; 83(6): 2675-85, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19109383

RESUMO

The long terminal repeat (LTR) retrotransposon Tf1 of Schizosaccharomyces pombe integrates specifically into the promoters of pol II-transcribed genes. Its integrase (IN) contains a C-terminal chromodomain related to the chromodomains that bind to the N-terminal tail of histone H3. Although we have been unable to detect an interaction between histone tails and the chromodomain of Tf1 IN, it is possible that the chromodomain plays a role in directing IN to its target sites. To test this idea, we generated transposons with single amino acid substitutions in highly conserved residues of the chromodomain and created a chromodomain-deleted mutant. The mutations, V1290A, Y1292A, W1305A, and CHDDelta, substantially reduced transposition activity in vivo. Blotting assays showed that there was little or no reduction in the levels of IN or cDNA. By measuring the homologous recombination between cDNA and the plasmid copy of Tf1, we found that two of the mutations did not reduce the import of cDNA into the nucleus, while another caused a 33% reduction. Chromatin immunoprecipitation assays revealed that CHDDelta caused an approximately threefold reduction in the binding of IN to the downstream LTR of the cDNA. These data indicate that the chromodomain contributed directly to integration. We therefore tested whether the chromodomain contributed to selecting insertion sites. Results of a target plasmid assay showed that the deletion of the chromodomain resulted in a drastic reduction in the preference for pol II promoters. Collectively, these data indicate that the chromodomain promotes binding of cDNA and plays a key role in efficient targeting.


Assuntos
DNA Complementar/metabolismo , Integrases/metabolismo , Recombinação Genética , Retroelementos , Schizosaccharomyces/genética , Sequência de Aminoácidos , Substituição de Aminoácidos/genética , Imunoprecipitação da Cromatina , Integrases/genética , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Estrutura Terciária de Proteína , Alinhamento de Sequência , Deleção de Sequência
13.
Int J Stem Cells ; 13(3): 342-352, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32840224

RESUMO

BACKGROUND AND OBJECTIVES: The directed differentiation of pluripotent stem cells into motor neurons is critical for the development of disease modelling and therapeutics to intervene degenerative motor neuron diseases. Cell surface receptor Cdo functions as a coreceptor for Sonic hedgehog (Shh) with Boc and Gas1 in the patterning of ventral spinal cord neurons including motor neurons. However, the discrete function of Cdo is not fully understood. METHODS AND RESULTS: In this study, we examined the role of Cdo in motor neuron generation by utilizing in vitro differentiation of Cdo+/+ and Cdo-/- embryonic stem cells (ESCs). In response to Shh, Cdo-/- ESCs exhibited impaired expression of motor neuron specification markers while dorsal interneuron specification markers were significantly increased, compared to Cdo+/+ ESCs. Reactivation of Shh signalling pathway with Smoothened (Smo) agonist (SAG) restored motor neuron specification in Cdo-/- ESCs. In addition, electrophysiological analysis revealed the immature electrical features of Cdo-/- ESCs-derived neurons which was restored by SAG. CONCLUSIONS: Taken together, these data suggest that Cdo as a Shh coreceptor is required for the induction of motor neuron generation by fully activating Shh signalling pathway and provide additional insights into the biology of motor neuron development.

14.
Cell Death Differ ; 27(1): 15-28, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31000813

RESUMO

Cellular senescence is implicated in aging or age-related diseases. Sonic hedgehog (Shh) signaling, an inducer of embryonic development, has recently been demonstrated to inhibit cellular senescence. However, the detailed mechanisms to activate Shh signaling to prevent senescence is not well understood. Here, we demonstrate that Protein arginine methyltransferase 7 (PRMT7) promotes Shh signaling via GLI2 methylation which is critical for suppression of cellular senescence. PRMT7-deficient mouse embryonic fibroblasts (MEFs) exhibited a premature cellular senescence with accompanied increase in the cell cycle inhibitors p16 and p21. PRMT7 depletion results in reduced Shh signaling activity in MEFs while PRMT7 overexpression enhances GLI2-reporter activities that are sensitive to methylation inhibition. PRMT7 interacts with and methylates GLI2 on arginine residues 225 and 227 nearby a binding region of SUFU, a negative regulator of GLI2. This methylation interferes with GLI2-SUFU binding, leading to facilitation of GLI2 nuclear accumulation and Shh signaling. Taken together, these data suggest that PRMT7 induces GLI2 methylation, reducing its binding to SUFU and increasing Shh signaling, ultimately leading to prevention of cellular senescence.


Assuntos
Senescência Celular , Proteína-Arginina N-Metiltransferases/metabolismo , Proteínas Repressoras/metabolismo , Proteína Gli2 com Dedos de Zinco/metabolismo , Arginina/metabolismo , Núcleo Celular , Células Cultivadas , Cílios/metabolismo , Proteínas Hedgehog/fisiologia , Metilação , Proteína-Arginina N-Metiltransferases/genética , Proteína-Arginina N-Metiltransferases/fisiologia , Proteínas Repressoras/antagonistas & inibidores , Transdução de Sinais , Proteína Gli2 com Dedos de Zinco/química
15.
Cell Death Dis ; 11(5): 359, 2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32398756

RESUMO

Various stresses, including oxidative stress, impair the proliferative capacity of muscle stem cells leading to declined muscle regeneration related to aging or muscle diseases. ZNF746 (PARIS) is originally identified as a substrate of E3 ligase Parkin and its accumulation is associated with Parkinson's disease. In this study, we investigated the role of PARIS in myoblast function. PARIS is expressed in myoblasts and decreased during differentiation. PARIS overexpression decreased both proliferation and differentiation of myoblasts without inducing cell death, whereas PARIS depletion enhanced myoblast differentiation. Interestingly, high levels of PARIS in myoblasts or fibroblasts induced cellular senescence with alterations in gene expression associated with p53 signaling, inflammation, and response to oxidative stress. PARIS overexpression in myoblasts starkly enhanced oxidative stress and the treatment of an antioxidant Trolox attenuated the impaired proliferation caused by PARIS overexpression. FoxO1 and p53 proteins are elevated in PARIS-overexpressing cells leading to p21 induction and the depletion of FoxO1 or p53 reduced p21 levels induced by PARIS overexpression. Furthermore, both PARIS and FoxO1 were recruited to p21 promoter region and Trolox treatment attenuated FoxO1 recruitment. Taken together, PARIS upregulation causes oxidative stress-related FoxO1 and p53 activation leading to p21 induction and cellular senescence of myoblasts.


Assuntos
Proteína Forkhead Box O1/metabolismo , Mioblastos/metabolismo , Estresse Oxidativo/fisiologia , Proteínas Repressoras/metabolismo , Envelhecimento/fisiologia , Animais , Antioxidantes/metabolismo , Diferenciação Celular/genética , Senescência Celular/fisiologia , Humanos , Camundongos , Proteína Supressora de Tumor p53/metabolismo
16.
Cell Signal ; 55: 100-108, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30639199

RESUMO

Neuritogenesis is a critical event for neuronal differentiation and neuronal circuitry formation during neuronal development and regeneration. Our previous study revealed a critical role of a guidance receptor BOC in a neuronal differentiation and neurite outgrowth. However, regulatory mechanisms for BOC signaling pathway remain largely unexplored. In the current study, we have identified Small glutamine-rich tetratricopeptide repeat (TPR)-containing b (SGTb) as a BOC interacting protein through yeast two-hybrid screening. Like BOC, SGTb is highly expressed in brain and P19 embryonal carcinoma (EC) cells differentiated into neuronal cells. BOC and SGTb proteins co-precipitate in mouse brain and differentiated P19 EC cells. Furthermore, BOC and SGTb co-localize in neurites and especially are concentrated at the tip of neurites in various neuronal cells. SGTb depletion attenuates neuronal differentiation of P19 cells through reduction of the surface level of BOC. Additionally, SGTb depletion causes BOC localization at neurite tip, coinciding with decreased p-JNK levels critical for actin cytoskeleton remodeling. The overexpression of SGTb or BOC restores JNK activation in BOC or SGTb-depleted cells, respectively. Finally, SGTb elevates the level of surface-resident BOC in BOC-depleted cells, restoring JNK activation. Taken together, our data suggest that SGTb interacts with BOC and regulates its surface level and consequent JNK activation, thereby promoting neuronal differentiation and neurite outgrowth.


Assuntos
Imunoglobulina G/metabolismo , Chaperonas Moleculares/fisiologia , Neuritos/metabolismo , Neurônios/metabolismo , Receptores de Superfície Celular/metabolismo , Citoesqueleto de Actina/metabolismo , Animais , Diferenciação Celular/fisiologia , Linhagem Celular , Humanos , Sistema de Sinalização das MAP Quinases/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Crescimento Neuronal , Neurônios/citologia , Saccharomyces cerevisiae
17.
Exp Mol Med ; 50(12): 1-9, 2018 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-30559345

RESUMO

Estrogen has diverse effects on cardiovascular function, including regulation of the contractile response to vasoactive substances such as serotonin. The serotonin system recently emerged as an important player in the regulation of vascular tone in humans. However, hyperreactivity to serotonin appears to be a critical factor for the pathophysiology of hypertension. In this study, we examined the modulatory mechanisms of estrogen in serotonin-induced vasoconstriction by using a combinatory approach of isometric tension measurements, molecular biology, and patch-clamp techniques. 17ß-Estradiol (E2) elicited a significant and concentration-dependent relaxation of serotonin-induced contraction in deendothelialized aortic strips isolated from male rats. E2 triggered a relaxation of serotonin-induced contraction even in the presence of tamoxifen, an estrogen receptor antagonist, suggesting that E2-induced changes are not mediated by estrogen receptor. Patch-clamp studies in rat arterial myocytes showed that E2 prevented Kv channel inhibition induced by serotonin. Serotonin increased Src activation in arterial smooth muscle required for contraction, which was significantly inhibited by E2. The estrogen receptor-independent inhibition of Src by E2 was confirmed in HEK293T cells that do not express estrogen receptor. Taken together, these results suggest that estrogen exerts vasodilatory effects on serotonin-precontracted arteries via Src, implying a critical role for estrogen in the prevention of vascular hyperreactivity to serotonin.


Assuntos
Aorta/patologia , Estrogênios/metabolismo , Artérias Mesentéricas/patologia , Vasoconstrição/fisiologia , Animais , Regulação para Baixo , Células HEK293 , Humanos , Masculino , Técnicas de Cultura de Órgãos , Técnicas de Patch-Clamp , Canais de Potássio de Abertura Dependente da Tensão da Membrana/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Estrogênio/metabolismo , Serotonina/metabolismo , Quinases da Família src/metabolismo
18.
Cell Signal ; 30: 30-40, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27871935

RESUMO

Neurite outgrowth is a critical step for neurogenesis and remodeling synaptic circuitry during neuronal development and regeneration. An immunoglobulin superfamily member, BOC functions as Sonic hedgehog (Shh) coreceptor in canonical and noncanonical Shh signaling in neuronal development and axon outgrowth/guidance. However signaling mechanisms responsible for BOC action during these processes remain unknown. In our previous studies, a multiprotein complex containing BOC and a closely related protein CDO promotes myogenic differentiation through activation of multiple signaling pathways, including non-receptor tyrosine kinase ABL. Given that ABL and Jun. N-terminal kinase (JNK) are implicated in actin cytoskeletal dynamics required for neurogenesis, we investigated the relationship between BOC, ABL and JNK during neuronal differentiation. Here, we demonstrate that BOC and ABL are induced in P19 embryonal carcinoma (EC) cells and cortical neural progenitor cells (NPCs) during neuronal differentiation. BOC-depleted EC cells or Boc-/- NPCs exhibit impaired neuronal differentiation with shorter neurite formation. BOC interacts with ABL through its putative SH2 binding domain and seems to be phosphorylated in an ABL activity-dependent manner. Unlike wildtype BOC, ABL-binding defective BOC mutants exhibit impaired JNK activation and neuronal differentiation. Finally, Shh treatment enhances JNK activation which is diminished by BOC depletion. These data suggest that BOC interacts with ABL and activates JNK thereby promoting neuronal differentiation and neurite outgrowth.


Assuntos
Diferenciação Celular , Proteínas Hedgehog/metabolismo , Imunoglobulina G/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Crescimento Neuronal , Neurônios/citologia , Proteínas Proto-Oncogênicas c-abl/metabolismo , Receptores de Superfície Celular/metabolismo , Motivos de Aminoácidos , Animais , Ativação Enzimática , Humanos , Imunoglobulina G/química , Camundongos , Mutação/genética , Neurônios/metabolismo , Fosforilação , Fosfotirosina/metabolismo , Ligação Proteica , Receptores de Superfície Celular/química , Domínios de Homologia de src
19.
PLoS One ; 12(4): e0175271, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28384253

RESUMO

Prevention of age-associated reduction in muscle mass and function is required to manage a healthy life. Supplemental (-)-Epicatechin (EC) appears to act as a potential regulator for muscle growth and strength. However, its cellular and molecular mechanisms as a potential muscle growth agent have not been studied well. In the current study, we investigated a role of EC in differentiation of muscle progenitors to gain the molecular insight into how EC regulates muscle growth. EC enhanced myogenic differentiation in a dose-dependent manner through stimulation of promyogenic signaling pathways, p38MAPK and Akt. EC treatment elevated MyoD activity by enhancing its heterodimerization with E protein. Consistently, EC also positively regulated myogenic conversion and differentiation of fibroblasts. In conclusion, EC has a potential as a therapeutic or nutraceutical remedy to treat degenerative muscle diseases or age-related muscle weakness.


Assuntos
Catequina/farmacologia , Diferenciação Celular/efeitos dos fármacos , Proteína MyoD/fisiologia , Mioblastos/citologia , Animais , Diferenciação Celular/fisiologia , Linhagem Celular , Camundongos
20.
PLoS One ; 11(7): e0158707, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27380411

RESUMO

A potassium channel Kir2.1-associated membrane hyperpolarization is required for myogenic differentiation. However the molecular regulatory mechanisms modulating Kir2.1 channel activities in early stage of myogenesis are largely unknown. A cell surface protein, Cdo functions as a component of multiprotein cell surface complexes to promote myogenesis. In this study, we report that Cdo forms a complex with Kir2.1 during myogenic differentiation, and is required for the channel activity by enhancing the surface expression of Kir2.1 in the early stage of differentiation. The expression of a constitutively active form of the upstream kinase for p38MAPK, MKK6(EE) can restore Kir2.1 activities in Cdo-depleted C2C12 cells, while the treatment with a p38MAPK inhibitor, SB203580 exhibits a similar effect of Cdo depletion on Kir2.1 surface expression. Furthermore, Cdo-/- primary myoblasts, which display a defective differentiation program, exhibit a defective Kir2.1 activity. Taken together, our results suggest that a promyogenic Cdo signaling is critical for Kir2.1 activities in the induction of myogenic differentiation.


Assuntos
Moléculas de Adesão Celular/metabolismo , Diferenciação Celular , Mioblastos/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Animais , Western Blotting , Moléculas de Adesão Celular/genética , Linhagem Celular , Membrana Celular/metabolismo , Células Cultivadas , Inibidores Enzimáticos/farmacologia , Imidazóis/farmacologia , MAP Quinase Quinase 6/metabolismo , Camundongos Knockout , Microscopia Confocal , Mioblastos/citologia , Canais de Potássio Corretores do Fluxo de Internalização/genética , Ligação Proteica , Piridinas/farmacologia , Interferência de RNA , Transdução de Sinais , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA