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1.
Nat Immunol ; 22(6): 711-722, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34017121

RESUMO

Chromatin undergoes extensive reprogramming during immune cell differentiation. Here we report the repression of controlled histone H3 amino terminus proteolytic cleavage (H3ΔN) during monocyte-to-macrophage development. This abundant histone mark in human peripheral blood monocytes is catalyzed by neutrophil serine proteases (NSPs) cathepsin G, neutrophil elastase and proteinase 3. NSPs are repressed as monocytes mature into macrophages. Integrative epigenomic analysis reveals widespread H3ΔN distribution across the genome in a monocytic cell line and primary monocytes, which becomes largely undetectable in fully differentiated macrophages. H3ΔN is enriched at permissive chromatin and actively transcribed genes. Simultaneous NSP depletion in monocytic cells results in H3ΔN loss and further increase in chromatin accessibility, which likely primes the chromatin for gene expression reprogramming. Importantly, H3ΔN is reduced in monocytes from patients with systemic juvenile idiopathic arthritis, an autoinflammatory disease with prominent macrophage involvement. Overall, we uncover an epigenetic mechanism that primes the chromatin to facilitate macrophage development.


Assuntos
Artrite Juvenil/imunologia , Diferenciação Celular/imunologia , Epigênese Genética/imunologia , Histonas/metabolismo , Leucócitos Mononucleares/metabolismo , Macrófagos/imunologia , Adolescente , Artrite Juvenil/sangue , Artrite Juvenil/genética , Sistemas CRISPR-Cas/genética , Catepsina G/genética , Catepsina G/metabolismo , Diferenciação Celular/genética , Núcleo Celular/metabolismo , Criança , Pré-Escolar , Cromatina/metabolismo , Ensaios Enzimáticos , Epigenômica , Feminino , Técnicas de Inativação de Genes , Humanos , Células Jurkat , Elastase de Leucócito/genética , Elastase de Leucócito/metabolismo , Leucócitos Mononucleares/imunologia , Macrófagos/metabolismo , Masculino , Mieloblastina/genética , Mieloblastina/metabolismo , Cultura Primária de Células , Proteólise , RNA-Seq , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Células THP-1 , Adulto Jovem
2.
Nature ; 565(7739): 372-376, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30626964

RESUMO

For more than 50 years, the methylation of mammalian actin at histidine 73 has been known to occur1. Despite the pervasiveness of His73 methylation, which we find is conserved in several model animals and plants, its function remains unclear and the enzyme that generates this modification is unknown. Here we identify SET domain protein 3 (SETD3) as the physiological actin His73 methyltransferase. Structural studies reveal that an extensive network of interactions clamps the actin peptide onto the surface of SETD3 to orient His73 correctly within the catalytic pocket and to facilitate methyl transfer. His73 methylation reduces the nucleotide-exchange rate on actin monomers and modestly accelerates the assembly of actin filaments. Mice that lack SETD3 show complete loss of actin His73 methylation in several tissues, and quantitative proteomics analysis shows that actin His73 methylation is the only detectable physiological substrate of SETD3. SETD3-deficient female mice have severely decreased litter sizes owing to primary maternal dystocia that is refractory to ecbolic induction agents. Furthermore, depletion of SETD3 impairs signal-induced contraction in primary human uterine smooth muscle cells. Together, our results identify a mammalian histidine methyltransferase and uncover a pivotal role for SETD3 and actin His73 methylation in the regulation of smooth muscle contractility. Our data also support the broader hypothesis that protein histidine methylation acts as a common regulatory mechanism.


Assuntos
Actinas/química , Actinas/metabolismo , Distocia/enzimologia , Distocia/prevenção & controle , Histidina/química , Histidina/metabolismo , Metiltransferases/metabolismo , Animais , Linhagem Celular , Feminino , Histona Metiltransferases , Histonas , Tamanho da Ninhada de Vivíparos/genética , Masculino , Metilação , Metiltransferases/deficiência , Metiltransferases/genética , Camundongos , Modelos Moleculares , Músculo Liso/citologia , Músculo Liso/fisiologia , Gravidez , Proteômica , Contração Uterina , Útero/citologia , Útero/fisiologia
3.
Pharmacol Res ; 187: 106636, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36586643

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a progressive disease with high mortality and limited therapeutic options. The immune checkpoint PD1/PD-L1 axis is related to the pathogenesis of pulmonary fibrosis, and upregulated expression levels of PD-L1 have been demonstrated in IPF patients. However, the mechanism of PD-L1 in pulmonary fibrosis is not fully understood. Here, we demonstrated upregulated expression of PD-L1 in fibrotic lung tissues and sera of IPF patients. Bleomycin (BLM) treatment induced PD-L1 upregulation, EMT (Epithelial-Mesenchymal Transition) and fibrosis-like morphology changes in human pulmonary alveolar epithelial cells (HPAEpiCs). Silencing PD-L1 attenuated BLM-induced EMT and fibrosis-like morphology changes in HPAEpiCs. In addition, we identified that PD-L1 directly binds to vimentin and inhibits vimentin ubiquitination, thereby increasing vimentin levels in HPAEpiCs. Silencing of vimentin inhibited BLM- and PD-L1-induced fibrosis in HPAEpiCs. The correlation between PD-L1 and EMT or vimentin expression was further confirmed in clinical samples and animal models. Finally, we used BLM- and paraquat-induced pulmonary fibrosis animal models to confirm the anti-pulmonary fibrosis effects of PD-L1 silencing. Taken together, our findings suggest that upregulated PD-L1 stimulates EMT of alveolar epithelial cells by increasing vimentin levels by inhibiting vimentin ubiquitination, thereby contributing to pulmonary fibrosis.


Assuntos
Antígeno B7-H1 , Fibrose Pulmonar Idiopática , Animais , Humanos , Regulação para Cima , Vimentina/genética , Vimentina/metabolismo , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Pulmão , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/genética , Fibrose Pulmonar Idiopática/metabolismo , Transição Epitelial-Mesenquimal , Bleomicina
4.
J Biol Chem ; 295(33): 11822-11832, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-32611769

RESUMO

Protein-lysine methylation is a common posttranslational modification (PTM) throughout the human proteome that plays important roles in diverse biological processes. In humans, there are >100 known and candidate protein lysine methyltransferases (PKMTs), many of which are linked to human diseases. Methyltransferase-like protein 21C (METTL21C) is a PKMT implicated in muscle biology that has been reported to methylate valosin-containing protein/p97 (VCP) and heat shock 70-kDa protein 8 (HSPA8). However, a clear in vitro methyltransferase activity for METTL21C remains yet to be demonstrated, and whether it is an active enzyme that directly methylates substrate(s) in vivo is unclear. Here, we used an unbiased biochemistry-based screening assay coupled to MS, which identified alanine tRNA synthetase 1 (AARS1) as a direct substrate of METTL21C. We found that METTL21C catalyzes methylation of Lys-943 of AARS1 (AARS1-K943me) both in vitro and in vivoIn vitro METTL21C-mediated AARS1 methylation was independent of ATP or tRNA molecules. Unlike for AARS1, and in conflict with previous reports, we did not detect METTL21C methylation of VCP and HSPA8. AARS1-K943 methylation in HEK293T cells depends upon METTL21C levels. Finally, METTL2C was almost exclusively expressed in muscle tissue, and, accordingly, we detected METTL21C-catalyzed methylation of AARS1 in mouse skeletal muscle tissue. These results reveal that AARS1 is a bona fide in vitro substrate of METTL21C and suggest a role for the METTL21C-AARS1 axis in the regulation of protein synthesis in muscle tissue. Moreover, our study describes a straightforward protocol for elucidating the physiological substrates of poorly characterized or uncharacterized PKMTs.


Assuntos
Metiltransferases/metabolismo , Músculo Esquelético/metabolismo , Animais , Células HEK293 , Humanos , Lisina/metabolismo , Metilação , Camundongos , Modelos Moleculares , Músculos/metabolismo
5.
Proc Natl Acad Sci U S A ; 115(16): 4218-4222, 2018 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-29610342

RESUMO

Reactive oxygen species formed within the mammalian cell can produce 8-oxo-7,8-dihydroguanine (8-oxoG) in mRNA, which can cause base mispairing during gene expression. Here we found that administration of 8-oxoGTP in MTH1-knockdown cells results in increased 8-oxoG content in mRNA. Under this condition, an amber mutation of the reporter luciferase is suppressed. Using second-generation sequencing techniques, we found that U-to-G changes at preassigned sites of the luciferase transcript increased when 8-oxoGTP was supplied. In addition, an increased level of 8-oxoG content in RNA induced the accumulation of aggregable amyloid ß peptides in cells expressing amyloid precursor protein. Our findings indicate that 8-oxoG accumulation in mRNA can alter protein synthesis in mammalian cells. Further work is required to assess the significance of these findings under normal physiological conditions.


Assuntos
Guanina/análogos & derivados , Mutagênese/genética , Biossíntese de Proteínas/genética , Transcrição Gênica/genética , Peptídeos beta-Amiloides/genética , Anticódon/genética , Pareamento de Bases , Códon sem Sentido , Enzimas Reparadoras do DNA/antagonistas & inibidores , Enzimas Reparadoras do DNA/genética , Técnicas de Silenciamento de Genes , Genes Reporter , Guanina/química , Células HeLa , Humanos , Luciferases/genética , Monoéster Fosfórico Hidrolases/antagonistas & inibidores , Monoéster Fosfórico Hidrolases/genética , Interferência de RNA , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Espécies Reativas de Oxigênio
6.
Zhongguo Dang Dai Er Ke Za Zhi ; 23(6): 613-620, 2021 Jun.
Artigo em Zh | MEDLINE | ID: mdl-34130784

RESUMO

OBJECTIVE: To study the clinical features and prognosis of children with acute megakaryocytic leukemia (AMKL) and the clinical effect of acute myeloid leukemia 03 (AML03) regimen for the treatment of pediatric AMKL. METHODS: The clinical data were collected from 47 children with AMKL who were diagnosed from May 2011 to December 2019. The treatment outcomes and prognostic factors were analyzed. The Kaplan-Meier method and the log-rank test were used for survival analysis. RESULTS: Among the 47 children with AMKL, 22 with non-Down syndrome-AMKL were treated by the AML03 regimen, with a median follow-up time of 11.4 months. For the 22 non-Down syndrome-AMKL patients, the remission rate of bone marrow cytology was 85% and the negative rate of minimal residual disease (MRD) was 79% after induction Ⅱ, with a 2-year overall survival (OS) rate of (50±13)% and a 2-year event-free survival (EFS) rate of (40±12)%. The group with positive immunophenotypic marker CD56 had significantly lower 2-year EFS and OS rates than the group with negative CD56 (P < 0.05). The group without remission of bone marrow cytology after induction Ⅱ had significantly lower 2-year EFS and OS rates than the group with remission (P < 0.05). The group with positive MRD after induction Ⅱ had a significantly lower 2-year EFS rate than the group with negative MRD (P < 0.05). There was no significant difference in 2-year OS and EFS rates between the patients with transplantation and those without transplantation (P > 0.05). CONCLUSIONS: Children with AMKL tend to have a low remission rate and a poor prognosis. Positive immunophenotypic marker CD56, bone marrow cytology during early treatment response, and MRD results are important factors influencing the prognosis. Allogeneic hematopoietic stem cell transplantation has no significant effect on the prognosis of AMKL.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Megacarioblástica Aguda , Criança , Intervalo Livre de Doença , Humanos , Leucemia Megacarioblástica Aguda/terapia , Neoplasia Residual , Prognóstico , Indução de Remissão , Taxa de Sobrevida , Resultado do Tratamento
7.
Mol Cell Biochem ; 475(1-2): 1-13, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32740791

RESUMO

Long non-coding RNAs are associated with the pathogenesis of cancers. Moreover, LINC00460 is involved in the development of multiple cancers. However, the function of LINC00460 in cervical cancer (CC) remains inconclusive. Herein, CC tissues and tumor-adjacent tissues were collected from patients. The effect of LINC00460 silencing in cell proliferation and apoptosis in CC was explored in vitro and in vivo. Additionally, the interaction between LINC00460 and miR-503-5p was analyzed using dual luciferase reporter assay. The expression of genes and proteins was assayed using quantitative real-time PCR, western blotting and immunohistochemistry, cell viability using MTT assay, cell cycle distribution using flow cytometry, cell apoptosis using Annexin V staining, Hoechst staining and TUNEL assay. LINC00460 levels in CC tissues were higher than tumor-adjacent tissues. LINC00460 silencing suppressed proliferation and promoted apoptosis of CC cells as evidenced by decreased cell viability, inhibited proliferation-related protein and cell cycle protein expressions and G1/S transition, increased apoptotic cells and Hoechst-positive cells, and enhanced apoptosis-related protein expressions. LINC00460 could bind to miR-503-5p and LINC00460 silencing enhanced miR-503-5p expression and inhibited its target gene expressions in CC cells. MiR-503-5p inhibition reversed LINC00460 silencing-caused inhibition of cell proliferation and miR-503-5p target gene expressions, and promotion of cell apoptosis. LINC00460 silencing also attenuated tumor growth, promoted miR-503-5p levels and cell apoptosis, and inhibited cell proliferation and miR-503-5p target gene expressions in tumor tissues. Hence, LINC00460 functioned as an oncogene in CC that affected cell proliferation and apoptosis via sponging miR-503-5p. This study provides a novel therapeutic target for CC.


Assuntos
MicroRNAs/genética , RNA Longo não Codificante/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia , Animais , Apoptose/fisiologia , Ciclo Celular/fisiologia , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Sobrevivência Celular/fisiologia , Bases de Dados Genéticas , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos Nus , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Taxa de Sobrevida , Neoplasias do Colo do Útero/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Mol Cell Biochem ; 467(1-2): 95-105, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32095930

RESUMO

Ovarian cancer has the highest mortality in gynecologic malignancies. LncRNA BLACAT1 serves crucial functions in various cancers, but its role in ovarian cancer has not been investigated. In this article, our team explored the role and the potential regulatory mechanism of BLACAT1 in ovarian cancer. Quantitative RT-PCR showed that BLACAT1 was aberrantly up-regulated in ovarian cancer tissues compared with normal tissues. In vitro, BLACAT1 knockdown induced cell cycle arrest and inhibited the proliferation, migration and invasion of ovarian cancer cells using flow cytometry, MTT and EdU assays, wound healing assay and transwell assay, respectively. Luciferase assay verified the binding relationship between microRNA-519d-3p and lncRNA BLACAT1, and BLACAT1 negatively regulated the expression of miR-519d-3p. We also found that miR-519d-3p overexpression could inhibit ovarian cancer cells proliferation, migration and invasion. Further, Western blot demonstrated that the expression of RPS15A and nuclear ß-catenin expression was markedly reduced by BLACAT1 knockdown, and cytoplasmic ß-catenin level was not obviously affected. In vivo, BLACAT1 knockdown inhibited the tumor growth, and immunohistochemistry showed that ki67 expression was decreased by BLACAT1 suppression. Inhibition of BLACAT1 was sufficient to down-regulate the expression of RPS15A and nuclear ß-catenin but did not cause an obvious change in cytoplasmic ß-catenin expression. Taken together, BLACAT1 knockdown inhibited the progression of ovarian cancer by suppressing the Wnt/ß-catenin signaling pathway via regulating miR-519d-3p. Our work provided a proper understanding of the critical roles of BLACAT1 in ovarian cancer.


Assuntos
Regulação para Baixo , MicroRNAs/genética , Neoplasias Ovarianas/patologia , RNA Longo não Codificante/genética , Via de Sinalização Wnt , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes/métodos , Humanos , Camundongos , Transplante de Neoplasias , Neoplasias Ovarianas/genética , Proteínas Ribossômicas/metabolismo , beta Catenina/metabolismo
9.
J Biol Chem ; 293(28): 11242-11250, 2018 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-29728458

RESUMO

In the yeast Saccharomyces cerevisiae, genomic instability in rDNA repeat sequences is an underlying cause of cell aging and is suppressed by the chromatin-silencing factor Sir2. In humans, rDNA instability is observed in cancers and premature aging syndromes, but its underlying mechanisms and functional consequences remain unclear. Here, we uncovered a pivotal role of sirtuin 7 (SIRT7), a mammalian Sir2 homolog, in guarding against rDNA instability and show that this function of SIRT7 protects against senescence in primary human cells. We found that, mechanistically, SIRT7 is required for association of SNF2H (also called SMARCA5, SWI/SNF-related matrix-associated actin-dependent regulator of chromatin, subfamily A, member 5), a component of the nucleolar heterochromatin-silencing complex NoRC, with rDNA sequences. Defective rDNA-heterochromatin silencing in SIRT7-deficient cells unleashed rDNA instability, with excision and loss of rDNA gene copies, which in turn induced acute senescence. Mounting evidence indicates that accumulation of senescent cells significantly contributes to tissue dysfunction in aging-related pathologies. Our findings identify rDNA instability as a driver of mammalian cellular senescence and implicate SIRT7-dependent heterochromatin silencing in protecting against this process.


Assuntos
Neoplasias Ósseas/patologia , Senescência Celular , DNA Ribossômico/genética , Epigênese Genética , Instabilidade Genômica , Osteossarcoma/patologia , Sirtuínas/metabolismo , Neoplasias Ósseas/genética , Neoplasias Ósseas/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Osteossarcoma/genética , Osteossarcoma/metabolismo , Sirtuínas/genética , Transcrição Gênica , Células Tumorais Cultivadas
10.
BMC Geriatr ; 19(1): 71, 2019 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-30836933

RESUMO

BACKGROUND: Body posture is a fundamental indicator for assessing health and quality of life, especially for elderly people. Deciphering the changes in body posture occurring with age is a current topic in the field of geriatrics. The aims of this study were to assess the parameters of standing body posture in the global sagittal plane and to determine the dynamics of changes in standing body posture occurring with age and differences between men and women. METHODS: The measurements were performed on 226 individuals between the ages of 20 to 89 with a new photogrammetry, via which we assessed five postural angles - neck, thorax, waist, hip and knee. The data were analyzed with t-test, one-way ANOVA, linear regression model and generalized additive model. RESULTS: Among these segments studied here, neck changed most, while the middle segments of the body, waist and hip, were relative stable. Significant differences between men and women were found with respect to the angles of neck, thorax and hip. Three of the five postural angles were significantly influenced with aging, including increasing cervical lordosis, thoracic kyphosis and knee flexion, starting from no older than around 50 yrs. showed by fitting curve derived with generalized additive model. These changes were more marked among women. Besides, this study highlights the effects of age and gender on the complex interrelation between adjacent body segments in standing. CONCLUSIONS: The presented results showed changes in the parameters describing body posture throughout consecutive ages and emphasized that for an individualized functional analysis, it is essential to consider age-and gender-specific changes in the neck, thorax and knee. This paper presents useful externally generalizable information not only for clinical purposes but also to inform further research on larger numbers of subjects.


Assuntos
Envelhecimento/patologia , Cifose/patologia , Postura , Vértebras Torácicas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Postura/fisiologia , Adulto Jovem
11.
FASEB J ; 31(6): 2533-2547, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28242773

RESUMO

Recent studies have shown that KIF5B (conventional kinesin heavy chain) mediates glucose transporter type 4 translocation and adiponectin secretion in 3T3-L1 adipocytes, suggesting an involvement of KIF5B in the homeostasis of metabolism. However, the in vivo physiologic function of KIF5B in adipose tissue remains to be determined. In this study, adipose-specific Kif5b knockout (F-K5bKO) mice were generated using the Cre-LoxP strategy. F-K5bKO mice had similar body weights to controls fed on a standard chow diet. However, F-K5bKO mice had hyperlipidemia and significant glucose intolerance and insulin resistance. Deletion of Kif5b aggravated the deleterious impact of a high-fat diet (HFD) on body weight gain, hepatosteatosis, glucose tolerance, and systematic insulin sensitivity. These changes were accompanied by impaired insulin signaling, decreased secretion of adiponectin, and increased serum levels of leptin and proinflammatory adipokines. F-K5bKO mice fed on an HFD exhibited lower energy expenditure and thermogenic dysfunction as a result of whitening of brown adipose due to decreased mitochondria biogenesis and down-regulation of key thermogenic gene expression. In conclusion, selective deletion of Kif5b in adipose tissue exacerbates HFD-induced obesity and its associated metabolic disorders, partly through a decrease in energy expenditure, dysregulation of adipokine secretion, and insulin signaling.-Cui, J., Pang, J., Lin, Y.-J., Gong, H., Wang, Z.-H., Li, Y.-X., Li, J., Wang, Z., Jiang, P., Dai, D.-P., Li, J., Cai, J.-P., Huang, J.-D., Zhang, T.-M. Adipose-specific deletion of Kif5b exacerbates obesity and insulin resistance in a mouse model of diet-induced obesity.


Assuntos
Tecido Adiposo/metabolismo , Dieta Hiperlipídica/efeitos adversos , Resistência à Insulina/fisiologia , Cinesinas/metabolismo , Obesidade/induzido quimicamente , Animais , Intolerância à Glucose , Resistência à Insulina/genética , Cinesinas/genética , Masculino , Camundongos , Camundongos Knockout
12.
Angew Chem Int Ed Engl ; 56(4): 1007-1011, 2017 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-27990725

RESUMO

Sirtuins are protein deacylases regulating metabolism and stress responses, and are implicated in aging-related diseases. Small molecule activators for the human sirtuins Sirt1-7 are sought as chemical tools and potential therapeutics, such as for cancer. Activators are available for Sirt1 and exploit its unique N-terminus, whereas drug-like activators for Sirt2-7 are lacking. We synthesized and screened pyrrolo[1,2-a]quinoxaline derivatives, yielding the first synthetic Sirt6 activators. Biochemical assays show direct, substrate-independent compound binding to the Sirt6 catalytic core and potent activation of Sirt6-dependent deacetylation of peptide substrates and complete nucleosomes. Crystal structures of Sirt6/activator complexes reveal that the compounds bind to a Sirt6-specific acyl channel pocket and identify key interactions. Our results establish potent Sirt6 activation with small molecules and provide a structural basis for further development of Sirt6 activators as tools and therapeutics.


Assuntos
Pirróis/metabolismo , Quinoxalinas/metabolismo , Sirtuínas/metabolismo , Bibliotecas de Moléculas Pequenas/metabolismo , Humanos , Modelos Moleculares , Estrutura Molecular , Pirróis/química , Quinoxalinas/química , Sirtuínas/química , Bibliotecas de Moléculas Pequenas/química
13.
Cell Physiol Biochem ; 40(1-2): 347-360, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27866193

RESUMO

BACKGROUND/AIMS: Salvia miltiorrhiza (SM) contains four major aqueous active ingredients, which have been isolated, purified and identified as danshensu (DSS), salvianolic acid A (Sal-A), salvianolic acid B (Sal-B) and protocatechuic aldehyde (PAL), totally abbreviated as SABP. Although SM is often used to treat various cardiovascular diseases in traditional Chinese medicine, the efficacy and function of optimal compatibility ratio of SM's active ingredients (SABP) in the prevention and treatment of cardiovascular diseases remain uncertain. This study investigated antihypertensive effect and underlying mechanisms of SABP vs. SM lyophilized powder (SMLP) in spontaneously hypertensive rats (SHR) and to establish the ratio of the optimal compatibility of DSS, Sal-A, Sal-B and PAL in improving cardiovascular functions. METHODS: The SHRs were treated with either SABP or SMLP and their systolic blood pressures (SBP) were monitored. The isolated thoracic aorta of SHRs was segregated for immunohistochemistry, Hematoxylin-Eosin stain and mRNA and protein expression of NOX4, TGF-ß1, Col-I, ET-1, α-SMA and Smad7. Moreover, the adventitial fibroblasts (AFs) were isolated and cultured from SD rats' aorta and the reactive oxygen species (ROS) production was determined after SABP or SMLP treatment. RESULTS: SABP, but not SMLP, significantly reduced SBP, which were accompanied by the inhibited morphological changes in the thoracic aorta and the reduced mRNA and protein expression of NOX4, TGF-ß1, Col-I, ET-1 and α-SMA, but the increased Smad 7 expression in SHRs. Moreover, SABP also resulted in a decreased ROS production in AFs of SD rats. CONCLUSIONS: These results indicate that SABP, but not SMLP, treatment potently inhibits hypertension through improvements of vascular remodeling and oxidative stress. The present study provides new evidence that the efficacy and function from optimal compatibility ratio of SM active ingredients is much better than its lyophilized powder, which represents a strategy to develop SM's new beneficial effect in improving cardiovascular functions.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Salvia miltiorrhiza/química , Remodelação Vascular/efeitos dos fármacos , Água/química , Actinas/genética , Actinas/metabolismo , Angiotensina II/sangue , Animais , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/patologia , Proliferação de Células/efeitos dos fármacos , Colágeno Tipo I/metabolismo , Endotelina-1/sangue , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Masculino , Malondialdeído/sangue , NADPH Oxidase 4 , NADPH Oxidases/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Endogâmicos SHR , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Proteína Smad7/genética , Proteína Smad7/metabolismo , Superóxido Dismutase/sangue , Sístole/efeitos dos fármacos , Fator de Crescimento Transformador beta1/sangue , Fator de Crescimento Transformador beta1/genética
14.
Biochem Biophys Res Commun ; 476(4): 620-626, 2016 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-27264953

RESUMO

Insulin stimulates adiponectin secretion and glucose transporter type 4 (GLUT4) translocation in adipocyte to regulate metabolism homeostasis. Similar to GLUT4 translocation, intracellular trafficking and release of adiponectin in adipocytes relies on the trans-Golgi network and endosomal system. Recent studies show that the heavy chain of conventional kinesin (KIF5B) mediates GLUT4 translocation in murine 3T3-L1 adipocytes, however, the motor machinery involved in mediating intracellular trafficking and release of adiponectin is unknown. Here, we examined the role of KIF5B in the regulation of adiponectin secretion. The KIF5B level was up-regulated during 3T3-L1 adipogenesis. This increase in cytosolic KIF5B was synchronized with the induction of adiponectin. Endogenous KIF5B and adiponectin were partially colocalized at the peri-nuclear and cytosolic regions. In addition, adiponectin-containing vesicles were co-immunoprecipitated with KIF5B. Knockdown of KIF5B resulted in a marked inhibition of adiponectin secretion and overexpression of KIF5B enhanced adiponectin release, whereas leptin secretion was not affected by changes in KIF5B expression. These data suggest that the secretion of adiponectin, but not leptin, is dependent on functional KIF5B.


Assuntos
Adipócitos/metabolismo , Adiponectina/metabolismo , Cinesinas/metabolismo , Células 3T3-L1 , Transporte Ativo do Núcleo Celular , Adipócitos/citologia , Adipogenia/genética , Adipogenia/fisiologia , Adiponectina/genética , Animais , Diferenciação Celular , Técnicas de Silenciamento de Genes , Transportador de Glucose Tipo 4/metabolismo , Cinesinas/genética , Leptina/genética , Leptina/metabolismo , Camundongos
15.
J Biol Chem ; 289(49): 34205-13, 2014 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-25344604

RESUMO

E2F1 and FOXO3 are two transcription factors that have been shown to participate in cellular senescence. Previous report reveals that E2F1 enhanced cellular senescence in human fibroblast cells, while FOXO transcription factors play against senescence by regulation reactive oxygen species scavenging proteins. However, their functional interplay has been unclear. Here we use E2F1 knock-out murine Embryonic fibroblasts (MEFs), knockdown RNAi constructs, and ectopic expression of E2F1 to show that it functions by negatively regulating FOXO3. E2F1 attenuates FOXO3-mediated expression of MnSOD and Catalase without affecting FOXO3 protein stability, subcellular localization, or phosphorylation by Akt. We mapped the interaction between E2F1 and FOXO3 to a region including the DNA binding domain of E2F1 and the C-terminal transcription-activation domain of FOXO3. We propose that E2F1 inhibits FOXO3-dependent transcription by directly binding FOXO3 in the nucleus and preventing activation of its target genes. Moreover, knockdown of the Caenorhabditis elegans E2F1 ortholog efl-1 significantly extends lifespan in a manner that requires the activity of the C. elegans FOXO gene daf-16. We conclude that there is an evolutionarily conserved signaling connection between E2F1 and FOXO3, which regulates cellular senescence and aging by regulating the activity of FOXO3. We speculate that drugs and/or therapies that inhibit this physical interaction might be good candidates for reducing cellular senescence and increasing longevity.


Assuntos
Envelhecimento/genética , Caenorhabditis elegans/genética , Senescência Celular/genética , Fator de Transcrição E2F1/genética , Fibroblastos/metabolismo , Fatores de Transcrição Forkhead/genética , Envelhecimento/metabolismo , Animais , Sítios de Ligação , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Catalase/genética , Catalase/metabolismo , Linhagem Celular , Fatores de Transcrição E2F/genética , Fatores de Transcrição E2F/metabolismo , Fator de Transcrição E2F1/antagonistas & inibidores , Fator de Transcrição E2F1/metabolismo , Embrião de Mamíferos , Fibroblastos/citologia , Proteína Forkhead Box O3 , Fatores de Transcrição Forkhead/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Células HEK293 , Humanos , Longevidade/genética , Camundongos , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
16.
J Cell Physiol ; 230(7): 1607-13, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25536389

RESUMO

High serum free fatty acids levels are associated with the development of insulin resistance in type 2 diabetes; however, the precise mechanisms underlying this lipid toxicity are unclear. To investigate whether PARP1 activation and NAD depletion are involved in the impairment of insulin sensitivity associated with lipotoxicity, HepG2 cells were cultured with 500 µM oleic acid for 48 h. Oleic acid-treated cells exhibited increased ROS generation, lipid accumulation and PARP1 activation. Treatment with the PARP1 inhibitor PJ34 and transfection with PARP1 small interfering RNA both prevented the oleic acid-induced impairment of the insulin signaling pathway. Furthermore, treatment with PJ34 reversed the oleic acid-induced decrease in intracellular NAD concentration, while exogenous NAD protected cells against oleic acid-induced insulin insensitivity. Combined NAD and PJ34 administration did not enhance the effects obtained by treatment with either NAD or PJ34 alone. Interestingly, when cells were treated with the SIRT1 inhibitor EX527, the protective effects of PJ34 and NAD treatment were diminished. Taken together, these data suggest that NAD depletion by PARP1 activation is essential for the modulation of insulin sensitivity in oleic acid-induced lipotoxicity.


Assuntos
Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , NAD/metabolismo , Ácido Oleico/farmacologia , Poli(ADP-Ribose) Polimerases/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Células Hep G2 , Humanos , Insulina/farmacologia , Resistência à Insulina , Metabolismo dos Lipídeos , NAD/genética , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases/genética , Espécies Reativas de Oxigênio/metabolismo , Sirtuína 1/genética , Sirtuína 1/metabolismo
17.
Cell Physiol Biochem ; 35(3): 1137-50, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25766526

RESUMO

BACKGROUND: Adventitial fibroblasts have been shown to play an important role in vascular remodeling and contribute to neointimal formation in vascular diseases. However, little is known about adventitial fibroblast subpopulations. This study explored the process of isolating rat thoracic aorta adventitial fibroblast subpopulations and characterized their properties following stimulation with angiotensin II (ANG II), a critical factor involved in cardiovascular diseases such as hypertension. METHODS: Adventitial fibroblasts were isolated and cultured from rat aorta. Fibroblast subpopulations were individually expanded using cloning ring techniques. Cells were treated with ANG II (10 nM, 100 nM and 1 µM) for 0.5, 1, 1.5, 3, 6, 12, or 24 h, and ANG II-induced proliferation and migration were measured by MTT assay and Transwell. Cells were treated with ANG II (100 nM) in the presence or absence of ANG II receptor antagonists (100 µM), losartan (for AT1) and PD-123319 (for AT2). PreproET-1 mRNA and ET-1 were determined by RT-PCR and ELISA, respectively. Collagen type I was detected by western blotting. RESULTS: Two major fibroblast subpopulations were found in the adventitia, epithelioid-like cells and spindle-like cells; Although ANG II promotes the growth of both subpopulations, epithelioid-like cell proliferation shows dose-dependency on ANG II from 10 nM to 1 µM, while proliferation of spindle-like cells reaches a peak value following 100 nM ANG II stimulation; ANG II stimulation enhanced epithelioid-like but not spindle-like cell migration; ANG II dose-dependently increased the expression of preproET-1 and collagen type I, and enhanced ET-1 secretion in epithelioid-like but not spindle-like cells, effects abolished by the AT1 receptor antagonist, but not with AT2 receptor antagonist. CONCLUSION: Adventitial fibroblasts are heterogeneous and epithelioid-like subpopulations with high sensitivity to ANG II stimulation may be implicated in the pathophysiological mechanisms of vascular remodeling, reparative processes and cardiovascular diseases.


Assuntos
Túnica Adventícia/efeitos dos fármacos , Aorta Torácica/efeitos dos fármacos , Linhagem da Célula/genética , Fibroblastos/efeitos dos fármacos , Túnica Adventícia/citologia , Angiotensina II/administração & dosagem , Bloqueadores do Receptor Tipo 2 de Angiotensina II/administração & dosagem , Animais , Aorta Torácica/citologia , Linhagem da Célula/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Colágeno Tipo I/biossíntese , Endotelina-1/biossíntese , Fibroblastos/citologia , Imidazóis/administração & dosagem , Losartan/administração & dosagem , Masculino , Piridinas/administração & dosagem , RNA Mensageiro/biossíntese , Ratos
18.
Cancer Causes Control ; 26(1): 133-41, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25416450

RESUMO

BACKGROUND: Growing body of laboratory evidence supports the beneficial effects of n-3 polyunsaturated fatty acids (PUFAs) on colorectal cancer (CRC) prevention. Epidemiologic studies investigating the relationship between n-3 PUFAs intake and risk of CRC, however, have been inconsistent. We aimed to clarify the relation by conducting a meta-analysis of prospective studies. METHODS: Eligible studies were identified by searching PubMed database and by carefully reviewing bibliographies of retrieved publications. Summary relative risks (RRs) with their 95 % confidence intervals (CIs) were computed with a random-effects model. Subgroup, meta-regression, and dose-response analyses were performed to explore potential sources of heterogeneity. RESULTS: A total of 14 prospective studies involving 8,775 cancer cases were included in the final analysis. Overall, total n-3 or marine PUFAs intake was not associated with risk of CRC (RR 0.99 and 1.00). However, there was a trend toward reduced risk of proximal colon cancer (total n-3 PUFAs: RR 0.83, 95 % CI 0.66-1.05; marine PUFAs: RR 0.81, 95 % CI 0.59-1.10) and a significant increased risk of distal colon cancer (total n-3 PUFAs: RR 1.26, 95 % CI 1.06-1.50; marine PUFAs: RR 1.38, 95 % CI 1.11-1.71). Furthermore, marine PUFAs intake accessed longer before diagnosis was associated 21 % reduced risk of CRC (RR 0.79, 95 % CI 0.63-1.00). CONCLUSION: Overall, this meta-analysis finds no relation between n-3 PUFAs intake and risk of CRC. The observed subsite heterogeneity within colon cancer and the possible effect modification by latency time merit further studies.


Assuntos
Neoplasias Colorretais/epidemiologia , Gorduras na Dieta/administração & dosagem , Ácidos Graxos Ômega-3/administração & dosagem , Neoplasias Colorretais/etiologia , Neoplasias Colorretais/prevenção & controle , Feminino , Humanos , Masculino , Estudos Prospectivos , Fatores de Risco
19.
Med Sci Monit ; 21: 992-1001, 2015 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-25841675

RESUMO

BACKGROUND: The aim of this study was to evaluate the efficiency of the combination of Paris and Vienna classifications in a follow-up study of gastric epithelial neoplasia (GEN) patients. MATERIAL AND METHODS: This study was conducted between January 2003 and September 2010, during which 170 biopsy-proven GEN patients were followed up by gastroenterologists and pathologists according to our follow-up regimen (modified Vienna classification). RESULTS: In total, 161 patients with low-grade neoplasia (LGN) and 9 patients with high-grade neoplasia (HGN) were randomly enrolled in our study. Eighteen patients with depressed appearance were observed, of which 9 patients had HGN and 9 patients had low-grade dysplasia (LGD). Three patients with type 0-IIa were observed with low-grade adenoma (LGA), and type 0-I was observed in 2 patients with LGN. Endoscopic or surgical treatments were performed to avoid potential malignancy or bleeding. Two patients with ulcer lesions, 2 patients with non-depressed type 0 appearance, and 3 patients without visible lesions were shown to have higher-grade lesions during follow-up. The misdiagnosis rate of forceps biopsy - 62.07% - was determined by comparing pre- and post-resection diagnoses of 29 patients. CONCLUSIONS: The combination of the Paris and Vienna classifications for GEN may optimize the follow-up routines for patients with suspicious precancerous lesions and may significantly improve the detection of early gastric cancer (EGC) while helping gastroenterologists select the best therapy option.


Assuntos
Epitélio/patologia , Neoplasias Gástricas/patologia , Adulto , Idoso , Biópsia , Demografia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Gástricas/classificação , Neoplasias Gástricas/terapia , Resultado do Tratamento
20.
Tumour Biol ; 35(12): 12151-6, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25155039

RESUMO

MicroRNAs (miRNAs) have recently been identified as a novel class of gene regulators, playing an important role in various malignancies. In the present study, we investigated the role of miRNA-130b in the development of drug resistance in ovarian cancer cells. The human ovarian carcinoma cell line A2780 and paclitaxel-resistant A2780/Taxol cells were exposed to the chemotherapeutic agent cisplatin or paclitaxel in the presence or absence of transfected miR-130b. Cell viability assays were then performed using the Cell Counting Kit-8 (CCK-8) assay. Reverse transcription polymerase chain reaction and Western blotting were used to assess the messenger RNA (mRNA) and protein expression levels of glutathione S-transferase (GST)-π, multidrug resistance (MDR)1, or P-glycoprotein (P-gp). Following transfection, we found higher expression levels of miR-130b in A2780/Taxol cells than in A2780 cells (p < 0.05). Both A2780 and A2780/Taxol cells showed decreased sensitivity to paclitaxel and cisplatin compared with mock-transfected and negative control cancer cells (p < 0.05). The mRNA expression levels of MDR1 and GST-π (p < 0.05) and the protein expression levels of P-gp and GST-π were downregulated following miR-130b transfection in comparison to mock-transfected and negative control cancer cells. Our findings suggest that miRNA-130b may be involved in the development of drug resistance in ovarian cancer.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , MicroRNAs/genética , Neoplasias Ovarianas/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Linhagem Celular Tumoral , Cisplatino/farmacologia , Feminino , Regulação Neoplásica da Expressão Gênica , Glutationa Transferase/genética , Humanos , Paclitaxel/farmacologia
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