Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 4.111
Filtrar
1.
Anticancer Res ; 39(10): 5473-5481, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31570441

RESUMO

BACKGROUND/AIM: Aerial parts and seeds of the neem tree (Azadirachta indica) have long been used in traditional medicine such as Ayurveda for health-related purposes. Our interest in neem bioactives lies in their potential use as standalone anticancer agents, or as adjuvants to standard therapy. The aim of the present study was to explore a supercritical CO2 extract (SCNE) of neem leaf and a prominent liminoid in neem leaf, nimbolide, for epigenetic activity. MATERIALS AND METHODS: Human colorectal cancer cell lines (HCT116 and HT29) were cultured for 48 h in the presence of neem extract or nimbolide and evaluated for growth inhibition and evidence of suppression of histone deacetylation and DNA methylation. RESULTS: Both SCNE and nimbolide suppressed the proliferation of colon cancer cells by inducing epigenetic modifications. CONCLUSION: Neem leaf contains bioactive constituents which modify epigenetic activity.


Assuntos
Azadirachta/química , Neoplasias Colorretais/tratamento farmacológico , Epigênese Genética/efeitos dos fármacos , Extratos Vegetais/farmacologia , Folhas de Planta/química , Dióxido de Carbono/química , Dióxido de Carbono/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Células HCT116 , Células HT29 , Humanos , Limoninas/farmacologia
3.
Anticancer Res ; 39(8): 4129-4136, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31366497

RESUMO

BACKGROUND/AIM: 5-Aza-2-deoxycytidine (5-Aza-CdR) enhances the sensitivity to 5-fluorouracil (5-FU), but the molecular mechanism is not fully understood. The aim of this study was to investigate the molecular mechanism that enhances the sensitivity to 5-FU treated with 5-Aza-CdR via thymidine phosphorylase (TP). MATERIALS AND METHODS: The sensitivity to drugs was determined on several cancer cell lines by the MTT assay. Protein and mRNA levels were examined by immunoblot and RT-PCR, respectively. Gene silencing, binding of Sp1 to DNA and methylation of DNA was performed by siRNA, ChIP assay and sodium bisulfate genomic sequencing, respectively. RESULTS: Sp1-binding sites in the TP promoter were methylated in epidermoid carcinoma. 5-Aza-CdR demethylated Sp1-binding sites and enhanced sensitivity to 5-FU. CONCLUSION: Demethylation of Sp1-binding sites by 5-Aza-CdR was a key factor enhancing 5-FU sensitivity, which may enable more effective treatments for cancer patients with the combination of 5-Aza-CdR and 5-FU.


Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Metilação de DNA/genética , Resistencia a Medicamentos Antineoplásicos/genética , Fator de Transcrição Sp1/genética , Timidina Fosforilase/genética , Sítios de Ligação/efeitos dos fármacos , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Proteínas de Ligação a DNA/genética , Decitabina/metabolismo , Fluoruracila/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inativação Gênica , Humanos , Regiões Promotoras Genéticas/efeitos dos fármacos , RNA Mensageiro/genética , Timidina Fosforilase/química
4.
Int J Nanomedicine ; 14: 4573-4587, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31296987

RESUMO

Introduction: Engineered nanoparticles (ENPs) are one of the most widely used types of nanomaterials. Recently, ENPs have been shown to cause cellular damage by inducing ROS (reactive oxygen species) both directly and indirectly, leading to the changes in DNA methylation levels, which is an important epigenetic mechanism. In this study, we investigated the effect of ENP-induced ROS on DNA methylation. Materials and methods: Human embryonic kidney and human keratinocyte (HaCaT) cells were exposed to three different types of ENPs: gold nanoparticles, silicon nanoparticles (SiNPs), and chitosan nanoparticles (CSNPs). We then evaluated the cytotoxicity of the ENPs by measuring cell viability, morphology, cell apoptosis, cell proliferation, cell cycle distribution and ROS levels. Global DNA methylation levels was measured using 5-methylcytosine immunocytochemical staining and HPLC analysis. DNA methylation levels of the transposable elements, long interspersed element-1 (LINE-1) and Alu, were also measured using combined bisulfite restriction analysis technique. DNA methylation levels of the TEs LINE-1 and Alu were also measured using combined bisulfite restriction analysis technique. Results: We found that HaCaT cells that were exposed to SiNPs exhibited increased ROS levels, whereas HaCaT cells that were exposed to SiNPs and CSNPs experienced global and Alu hypomethylation, with no change in LINE-1 being observed in either cell line. The demethylation of Alu in HaCaT cells following exposure to SiNPs and CSNPs was prevented when the cells were pretreated with an antioxidant. Conclusion: The global DNA methylation that is observed in cells exposed to ENPs is associated with methylation of the Alu elements. However, the change in DNA methylation levels following ENP exposure is specific to particular ENP and cell types and independent of ROS, being induced indirectly through disruption of the oxidative defense process.


Assuntos
Acetilcisteína/farmacologia , Metilação de DNA/efeitos dos fármacos , Nanopartículas/química , Nanopartículas/toxicidade , Elementos Alu/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Quitosana/metabolismo , Epigênese Genética , Ouro/metabolismo , Humanos , Queratinócitos/efeitos dos fármacos , Elementos Nucleotídeos Longos e Dispersos/efeitos dos fármacos , Coroa de Proteína , Espécies Reativas de Oxigênio/metabolismo , Silício/química
5.
Nat Commun ; 10(1): 3081, 2019 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-31300673

RESUMO

Dimethyl fumarate (DMF) is a first-line-treatment for relapsing-remitting multiple sclerosis (RRMS). The redox master regulator Nrf2, essential for redox balance, is a target of DMF, but its precise therapeutic mechanisms of action remain elusive. Here we show impact of DMF on circulating monocytes and T cells in a prospective longitudinal RRMS patient cohort. DMF increases the level of oxidized isoprostanes in peripheral blood. Other observed changes, including methylome and transcriptome profiles, occur in monocytes prior to T cells. Importantly, monocyte counts and monocytic ROS increase following DMF and distinguish patients with beneficial treatment-response from non-responders. A single nucleotide polymorphism in the ROS-generating NOX3 gene is associated with beneficial DMF treatment-response. Our data implicate monocyte-derived oxidative processes in autoimmune diseases and their treatment, and identify NOX3 genetic variant, monocyte counts and redox state as parameters potentially useful to inform clinical decisions on DMF therapy of RRMS.


Assuntos
Fumarato de Dimetilo/uso terapêutico , Imunossupressores/uso terapêutico , Monócitos/imunologia , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , NADPH Oxidases/genética , Adulto , Metilação de DNA/efeitos dos fármacos , Fumarato de Dimetilo/farmacologia , Epigênese Genética/efeitos dos fármacos , Feminino , Humanos , Imunossupressores/farmacologia , Contagem de Leucócitos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo , Esclerose Múltipla Recidivante-Remitente/sangue , Esclerose Múltipla Recidivante-Remitente/imunologia , NADPH Oxidases/metabolismo , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Fator 2 Relacionado a NF-E2/metabolismo , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos , Espécies Reativas de Oxigênio/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Resultado do Tratamento
6.
Life Sci ; 231: 116576, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31211998

RESUMO

AIMS: Studies suggest that cardiovascular function in offspring can be epigenetically programmed by environmental changes during pregnancy. CaV1.2 channel plays a major role in the regulation of the vascular tone. This study investigated the effects and underlying mechanisms of exercise during pregnancy on CaV1.2 channel functional remodeling in hypertensive offspring. MAIN METHODS: Exercise groups were subjected to swimming at the first day of pregnancy and on a regular schedule thereafter for 3 weeks. Their offspring (6-month-old, male) were tested for baseline blood pressure, cardiovascular response, and vascular tone of the mesenteric artery. Mesenteric artery smooth muscle cells were taken to study the whole-cell current of the CaV1.2 channel. Western blotting, RT-PCR and DNA bisulfite sequencing PCR were performed to study the protein, mRNA expression and DNA methylation of the CaV1.2 channel α1C subunit. KEY FINDINGS: Exercise during pregnancy reduced the pressor response to norepinephrine and Bay K8644, and the depressor response to nifedipine in offspring of hypertensive rats. The level of the CaV1.2 channel in norepinephrine-induced vasoconstrictions decreased, and the whole-cell current of the CaV1.2 channel declined in the SHR-EX group. Further studies found that exercise during pregnancy reduced the protein and mRNA expression of the CaV1.2 channel α1C subunit and upregulated DNA methylation of the Cacna1c gene promoter region in the hypertensive offspring. SIGNIFICANCE: These data suggest that exercise during pregnancy improves vascular functional remodeling in offspring of hypertensive rats, downregulating the CaV1.2 channel function and protein expression, a change that is most likely caused by DNA methylation.


Assuntos
Canais de Cálcio Tipo L/fisiologia , Hipertensão/fisiopatologia , Condicionamento Físico Animal/fisiologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Canais de Cálcio Tipo L/genética , Canais de Cálcio Tipo L/metabolismo , Metilação de DNA/efeitos dos fármacos , Regulação para Baixo , Epigênese Genética/genética , Repressão Epigenética , Feminino , Masculino , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Gravidez , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Regulação para Cima , Vasoconstrição/efeitos dos fármacos
7.
Gastroenterology ; 157(3): 744-759.e4, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31154022

RESUMO

BACKGROUND & AIMS: Many genetic and environmental factors, including family history, dietary fat, and inflammation, increase risk for colon cancer development. Peroxisome proliferator-activated receptor alpha (PPARα) is a nuclear receptor that regulates systemic lipid homeostasis. We explored the role of intestinal PPARα in colon carcinogenesis. METHODS: Colon cancer was induced in mice with intestine-specific disruption of Ppara (PparaΔIE), Pparafl/fl (control), and mice with disruption of Ppara that express human PPARA (human PPARA transgenic mice), by administration of azoxymethane with or without dextran sulfate sodium (DSS). Colons were collected from mice and analyzed by immunoblots, quantitative polymerase chain reaction, and histopathology. Liquid chromatography coupled with mass spectrometry-based metabolomic analyses were performed on urine and colons. We used molecular biology and biochemical approaches to study mechanisms in mouse colons, primary intestinal epithelial cells, and colon cancer cell lines. Gene expression data and clinical features of patients with colorectal tumors were obtained from Oncomine, and human colorectal-tumor specimens and adjacent normal tissues were collected and analyzed by immunohistochemistry. RESULTS: Levels of Ppara messenger RNA were reduced in colon tumors from mice. PparaΔIE mice developed more and larger colon tumors than control mice following administration of azoxymethane, with or without DSS. Metabolomic analyses revealed increases in methylation-related metabolites in urine and colons from PparaΔIE mice, compared with control mice, following administration of azoxymethane, with or without DSS. Levels of DNA methyltransferase 1 (DNMT1) and protein arginine methyltransferase 6 (PRMT6) were increased in colon tumors from PparaΔIE mice, compared with colon tumors from control mice. Depletion of PPARα reduced the expression of retinoblastoma protein, resulting in increased expression of DNMT1 and PRMT6. DNMT1 and PRMT6 decreased expression of the tumor suppressor genes Cdkn1a (P21) and Cdkn1b (p27) via DNA methylation and histone H3R2 dimethylation-mediated repression of transcription, respectively. Fenofibrate protected human PPARA transgenic mice from azoxymethane and DSS-induced colon cancer. Human colon adenocarcinoma specimens had lower levels of PPARA and retinoblastoma protein and higher levels of DNMT1 and PRMT6 than normal colon tissues. CONCLUSIONS: Loss of PPARα from the intestine promotes colon carcinogenesis by increasing DNMT1-mediated methylation of P21 and PRMT6-mediated methylation of p27 in mice. Human colorectal tumors have lower levels of PPARA messenger RNA and protein than nontumor tissues. Agents that activate PPARα might be developed for chemoprevention or treatment of colon cancer.


Assuntos
Adenocarcinoma/prevenção & controle , Colo/enzimologia , Neoplasias do Colo/prevenção & controle , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , Metilação de DNA , Proteínas Nucleares/metabolismo , PPAR alfa/metabolismo , Proteína-Arginina N-Metiltransferases/metabolismo , Adenocarcinoma/enzimologia , Adenocarcinoma/genética , Adenocarcinoma/patologia , Animais , Anticarcinógenos/farmacologia , Estudos de Casos e Controles , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Colo/patologia , Neoplasias do Colo/enzimologia , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , DNA (Citosina-5-)-Metiltransferase 1/genética , Metilação de DNA/efeitos dos fármacos , Bases de Dados Genéticas , Modelos Animais de Doenças , Fenofibrato/farmacologia , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Nucleares/genética , PPAR alfa/agonistas , PPAR alfa/deficiência , PPAR alfa/genética , Proteína-Arginina N-Metiltransferases/genética , Transdução de Sinais
8.
Gene ; 711: 143941, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31242453

RESUMO

Inorganic arsenic is a well-known carcinogen associated with several types of cancer, but the mechanisms involved in arsenic-induced carcinogenesis are not fully understood. Recent evidence points to epigenetic dysregulation as an important mechanism in this process; however, the effects of epigenetic alterations in gene expression have not been explored in depth. Using microarray data and applying a multivariate clustering analysis in a Gaussian mixture model, we describe the alterations in DNA methylation around the promoter region and the impact on gene expression in HaCaT cells during the transformation process caused by chronic exposure to arsenic. Using this clustering approach, the genes were grouped according to their methylation and expression status in the epigenetic landscape, and the changes that occurred during the cellular transformation were identified adequately. Thus, we present a valuable method for identifying epigenomic dysregulation.


Assuntos
Arsênico/toxicidade , Transformação Celular Neoplásica/patologia , Metilação de DNA/efeitos dos fármacos , Perfilação da Expressão Gênica/métodos , Neoplasias Cutâneas/patologia , Animais , Linhagem Celular Tumoral , Transformação Celular Neoplásica/induzido quimicamente , Transformação Celular Neoplásica/genética , Epigênese Genética/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Transplante de Neoplasias , Análise de Sequência com Séries de Oligonucleotídeos , Regiões Promotoras Genéticas , Neoplasias Cutâneas/induzido quimicamente , Neoplasias Cutâneas/genética
9.
Environ Pollut ; 252(Pt A): 216-226, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31151060

RESUMO

Microcystins (MCs) have been shown to be carcinogenic by animal and cellular experiments and found to be associated with the development of human hepatocellular carcinoma (HCC) through epidemiological studies. However, the molecular mechanism of microcystin-LR (MC-LR) induced HCC is still unclear. This study is determined to clarify the role and mechanism of LHX6 in MC-LR-induced hepatocarcinogenesis. Using the previously established MC-LR-induced malignant transformation model in L02 cells, we screened out LHX6, homeobox gene that was significantly changed. We found that LHX6 was significantly down-regulated in MC-LR treated L02 cells and the liver tissue of rats treated for 35 weeks with 10 µg/kg body weight of MC-LR. Expression of LHX6 in human tumor tissue was significantly down-regulated in high MC-LR-exposure group. LHX6 was hypermethylated in MC-LR treated L02 cells and up-regulated after treatment with 10 µM of 5-aza-2'-deoxycytidine. Furthermore, overexpression of LHX6 inhibited proliferation, invasion and migration of malignantly transformed L02 cells in vitro and in vivo, while knockdown of LHX6 resulted in an opposite phenotype. In addition, we found that up-regulation of P53 and Bax resulted in apoptosis, and that down-regulation of CTNNB1 and MMP7 led to migration of MC-LR treated L02 cells. Blockade of P53 and CTNNB1 by its inhibitor significantly diminished the effect of LHX6. These genes were working together during the process of MC-LR-induced hepatocarcinogenesis. Our study demonstrated for the first time that LHX6 gene expression is regulated by DNA methylation and can inhibit the proliferation, invasion and migration through Wnt/ß-catenin and P53 signaling pathways during the MC-LR-induced hepatocarcinogenesis. This result may suggest that LHX6 gene can be used as a potential target gene and a biomarker for liver cancer treatment.


Assuntos
Carcinoma Hepatocelular/induzido quimicamente , Transformação Celular Neoplásica/induzido quimicamente , Proteínas com Homeodomínio LIM/metabolismo , Neoplasias Hepáticas/induzido quimicamente , Microcistinas/toxicidade , Proteínas do Tecido Nervoso/metabolismo , Fatores de Transcrição/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Transformação Celular Neoplásica/genética , Metilação de DNA/efeitos dos fármacos , Decitabina/farmacologia , Epigênese Genética , Humanos , Proteínas com Homeodomínio LIM/genética , Metaloproteinase 7 da Matriz/metabolismo , Proteínas do Tecido Nervoso/genética , Ratos , Transdução de Sinais , Fatores de Transcrição/genética , Proteína Supressora de Tumor p53/antagonistas & inibidores , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima , beta Catenina/antagonistas & inibidores , beta Catenina/metabolismo
10.
Curr Top Med Chem ; 19(15): 1350-1362, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31215380

RESUMO

Macrophages are essential for supporting tissue homeostasis, regulating immune response, and promoting tumor progression. Due to its heterogeneity, macrophages have different phenotypes and functions in various tissues and diseases. It is becoming clear that epigenetic modification playing an essential role in determining the biological behavior of cells. In particular, changes of DNA methylation, histone methylation and acetylation regulated by the corresponding epigenetic enzymes, can directly control macrophages differentiation and change their functions under different conditions. In addition, epigenetic enzymes also have become anti-tumor targets, such as HDAC, LSD1, DNMT, and so on. In this review, we presented an overview of the latest progress in the study of macrophages phenotype and function regulated by epigenetic modifications, including DNA methylation and histone modifications, to better understand how epigenetic modification controls macrophages phenotype and function in inflammation-associated diseases, and the application prospect in anti-tumor.


Assuntos
Antineoplásicos/farmacologia , Epigênese Genética/efeitos dos fármacos , Inflamação/tratamento farmacológico , Macrófagos/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Acetilação/efeitos dos fármacos , Animais , Antineoplásicos/química , Metilação de DNA/efeitos dos fármacos , Epigênese Genética/genética , Histonas/efeitos dos fármacos , Histonas/metabolismo , Humanos , Inflamação/metabolismo , Inflamação/patologia , Macrófagos/metabolismo , Macrófagos/patologia , Metilação/efeitos dos fármacos , Neoplasias/metabolismo , Neoplasias/patologia
11.
J Food Sci ; 84(7): 1979-1985, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31206673

RESUMO

Essential oils (EO) are widely used in foods as flavoring and preservative agents. Many of the biological activities of EO have been attributed to major essential oil compounds (EOC) but their direct interaction with colonic epithelial cells and their genotoxic and genoprotective effects are not well established. In this study, the cytotoxicity and genotoxicity of EOC including nerolidol, thymol, geraniol, methylisoeugenol, eugenol, linalool, and a commercial blend (Agolin) were determined. Furthermore, the genoprotective effects of EOC against oxidative and methylating damage were assessed using the comet assay in HT-29 colorectal adenocarcinoma cells. The majority of EOC were cytotoxic to HT-29 cells at or above 250 ppm after 24 hr exposure. At noncytotoxic doses, none of the EOC was genotoxic in the comet assay. Genoprotection against oxidative DNA damage was observed for nerolidol (at 62.5 ppm), thymol (at 12.5 ppm), geraniol, and methylisoeugenol (both at 125 ppm), as well as linalool and Agolin (both at 250 ppm). Thymol was the most protective compound against oxidative DNA damage and geraniol (at 125 ppm) also protected cells against methylating DNA damage. This study highlights the potential of EOC such as thymol to protect the colonic epithelium against oxidative DNA damage and geraniol against methylating DNA damage. Further in vivo studies are needed to confirm these findings for safety and efficacy to exploit their potential pharmaceutical or nutraceutical uses for colonic health.


Assuntos
Dano ao DNA/efeitos dos fármacos , Óleos Voláteis/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Linhagem Celular Tumoral , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Ensaio Cometa , Metilação de DNA/efeitos dos fármacos , Eugenol/análise , Eugenol/farmacologia , Humanos , Monoterpenos/análise , Monoterpenos/farmacologia , Óleos Voláteis/análise , Substâncias Protetoras/análise , Terpenos/análise , Terpenos/farmacologia , Timol/análise , Timol/farmacologia
12.
Environ Pollut ; 252(Pt B): 1267-1276, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31252124

RESUMO

Metal pollution has been associated with anthropogenic activities, such as effluents and emissions from mines. Soil could be exposure route of wild rats to metals, especially in mining areas. The aim of this study was to verify whether soil exposure under environmentally relevant circumstances results in metal accumulation and epigenetic modifications. Wistar rats were divided to three groups: 1) control without soil exposure, 2) low-metal exposure group exposed to soil containing low metal levels (Pb: 75 mg/kg; Cd: 0.4), and 3) high-metal exposure group exposed to soil (Pb: 3750; Cd: 6). After 1 year of exposure, the metal levels, Pb isotopic values, and molecular indicators were measured. Rats in the high-group showed significantly greater concentrations of Pb and Cd in tissues. Higher accumulation factors (tissue/soil) of Cd than Pb were observed in the liver, kidney, brain, and lung, while the factor of Pb was higher in the tibia. The obtained results of metal accumulation ratios (lung/liver) and stable Pb isotope ratios in the tissues indicated that the respiratory exposure would account for an important share of metal absorption into the body. Genome-wide methylation status and DNA methyltransferase (Dnmt 3a/3b) mRNA expressions in testis were higher in the high-group, suggesting that exposure to soil caused metal accumulation and epigenetic alterations in rats.


Assuntos
Cádmio/análise , Metilação de DNA/efeitos dos fármacos , Poluição Ambiental/análise , Chumbo/análise , Poluentes do Solo/análise , Animais , Cádmio/toxicidade , DNA (Citosina-5-)-Metiltransferases/metabolismo , Chumbo/toxicidade , Masculino , Mineração , Ratos , Ratos Wistar , Solo/química , Poluentes do Solo/toxicidade
13.
Mol Med Rep ; 19(6): 5023-5029, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31059005

RESUMO

Multiple myeloma (MM) is an incurable disease; a better understanding of the molecular aspects of this hematological malignancy could contribute to the development of new treatment strategies and help to improve the survival rates of patients with MM. Previously, the methylation status of the deleted in colorectal cancer (DCC) gene was correlated with the survival rate of patients with MM, thus the main goal of this study was to understand DCC contribution to MM tumorigenesis, and to assess the impact of DCC inhibition in the MM response to treatment with bortezomib. Our results demonstrated that hypermethylation of the DCC promoter inhibits gene expression, and DCC silencing is significantly correlated with a reduction in cell viability and an increase in cell death induced by bortezomib. In conclusion, our results suggested that hypermethylation is an important mechanism of DCC expression regulation in MM and that the absence of DCC contributes to the enhanced sensitivity to treatment with bortezomib.


Assuntos
Bortezomib/farmacologia , Receptor DCC/metabolismo , Regulação para Baixo/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Receptor DCC/antagonistas & inibidores , Receptor DCC/genética , Metilação de DNA/efeitos dos fármacos , Humanos , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , Regiões Promotoras Genéticas , Interferência de RNA , RNA Interferente Pequeno/metabolismo
14.
Chemosphere ; 230: 384-395, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31112861

RESUMO

Recently, environment contaminants including pesticides, fungicides, mycotoxin and others chemicals have been suggested to be responsible for the decline in the human spermatozoa quality especially motility and the increase in infertility rate. Chlorothalonil is used widely for protection of vegetables and crops because it is a broad spectrum fungicide. It has been reported that chronic occupational exposure to fungicides was associated with poor spermatozoa morphology in young men. The pubertal period is very important for the male reproductive system development due to spermatogonial cell proliferation, the expansion of meiotic and haploid germ cells. Although some investigations have studied the male reproductive toxicity of chlorothalonil, almost no studies focused on spermatogenesis. The aim of our current investigation was to explore the impacts of chlorothalonil on spermatogenesis and the underlying mechanisms. It demonstrates: i) chlorothalonil decreased boar spermatozoa motility in vitro and increased the cell apoptosis; ii) chlorothalonil inhibited mouse spermatogenesis in vivo; iii) chlorothalonil disturbed spermatogenesis through the disruption of estrogen receptor signalling; iv) chlorothalonil disrupted histone methylation and DNA methylation which might be through estrogen signalling pathways. Due to the over use or incorrect use, chlorothalonil might cause serious problems to human health, especially spermatogenesis. Therefore we strongly recommend that greater attention should be paid to this fungicide to minimise its impact on human health especially spermatogenesis.


Assuntos
Metilação de DNA/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Fungicidas Industriais/toxicidade , Histonas/metabolismo , Nitrilos/toxicidade , Receptores Estrogênicos/metabolismo , Espermatogênese/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Masculino , Camundongos Endogâmicos ICR , Transdução de Sinais , Motilidade Espermática/efeitos dos fármacos , Espermatogênese/genética , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Espermatozoides/patologia , Suínos
15.
Chemosphere ; 228: 586-594, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31059956

RESUMO

BACKGROUND: Benzo[a]pyrene (BaP) is an environmental pollutant known to cause teratogenesis. However, the mechanism underlying this teratogenic effect is not fully understood. Recently, the alteration of DNA methylation of imprinting genes has emerged as a specific epigenetic mechanism linking the impact of environmental pollutants on embryonic development to paternal exposures. The aim of this study was to investigate the transgenerational effects of paternal BaP exposure on the imprinting genes in mouse sperm DNA. METHODS: Male C57BL/6J mice received BaP (1.0 or 2.5 mg/kg) or olive oil twice a week for 12 weeks. The methylation status of 6 imprinting genes (H19, Meg3, Peg1, Peg3, Igf2 and Snrpn) was examined by bisulfite pyrosequencing of the sperm DNA of BaP-exposed F0 generation and their offspring. RESULTS: BaP exposure reduced the methylation levels in the imprinting genes H19 and Meg3 and increased the methylation levels of Peg1 and Peg3; however, no significant differences was observed for the methylation levels of Igf2 or Snrpn in the sperm DNA. Furthermore, BaP-exposed male mice were mated with unexposed female mice to generate F1-2 generations. The methylation levels of the 6 genes in the sperm DNA from F1-2 offspring showed a similar pattern as that of the F0 male. The effects were attenuated in F1-2 generations. CONCLUSIONS: Paternal BaP exposure altered the methylation levels of imprinting genes, implicating that imprinting genes are susceptible to environmental toxicants. Furthermore, a similar alteration was observed in the F1-2 generations although the attenuated in methylation in F2 generation, revealing a potential transgenerational effect.


Assuntos
Benzo(a)pireno/farmacologia , Metilação de DNA/efeitos dos fármacos , Impressão Genômica/genética , Exposição Paterna , Espermatozoides/efeitos dos fármacos , Animais , Poluentes Ambientais/farmacologia , Epigênese Genética/efeitos dos fármacos , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , Reprodução/efeitos dos fármacos
16.
BMC Genomics ; 20(1): 324, 2019 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-31035926

RESUMO

BACKGROUND: During decidualization in endometrial stromal cells (ESCs), expressions of a number of genes and epigenetic modifications of histones are altered. However, there is little information about whether DNA methylation, which is another epigenetic mechanism, also changes during decidualization. Here, we examined the genome-wide DNA methylation profiles in ESCs during decidualization and their associations with the changes of gene expressions and histone modifications. RESULTS: ESCs were incubated with estradiol and medroxyprogesterone acetate for 14 days to induce decidualization. The genome-wide DNA methylation profiles were compared between the non-decidualized ESCs and the decidualized ESCs. Of 482,005 CpGs, only 23 CpGs (0.0048%) showed different DNA methylation statuses. The DNA methylation statuses of the differentially expressed genes and the regions with different histone modifications (H3K4 tri-methylation and H3K27 acetylation) were also compared between the ESCs. In the upregulated and downregulated genes in decidualized ESCs, DNA methylation statuses around the promoter region of the genes did not significantly differ between the ESCs. In the regions with different histone modification, DNA methylation statuses did not differ between the ESCs. The differentially expressed genes and the differential histone modification regions were hypomethylated. CONCLUSIONS: Culturing ESCs with estrogen/progesterone did not distort the physiological pattern of DNA methylation, although mRNA expression and histone modifications were dynamically altered. A genome-wide DNA methylation analysis revealed stable DNA methylation statuses during decidualization in human endometrial stromal cells. DNA hypomethylation is maintained for the variable changes of histone modifications and gene expression during decidualization.


Assuntos
Metilação de DNA , Genoma Humano , Células Cultivadas , Ilhas de CpG , Metilação de DNA/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Endométrio/citologia , Estradiol/farmacologia , Feminino , Histonas/metabolismo , Humanos , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Acetato de Medroxiprogesterona/farmacologia , Células Estromais/citologia , Células Estromais/metabolismo , Regulação para Cima/efeitos dos fármacos
17.
Environ Pollut ; 252(Pt A): 39-50, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31146237

RESUMO

Exposure to ultrafine particulate matter (PM0.1) is positively associated with the etiology of different acute and chronic disorders; however, the in-depth biological imprints that link these submicron particles with the disturbances in the epigenomic machinery are not well defined. Earlier, we showed that exposure to these particles causes significant disturbances in the mitochondrial machinery and triggers PI-3-kinase mediated DNA damage responses. In the present study, we aimed to further understand the epigenomic insights of the ultrafine PM exposure. The higher levels of intracellular reactive oxygen species and depleted Nrf-2 in ultrafine PM exposed cells reconfirmed its potential to induce oxidative stress. Importantly, the observed increase in the levels of NF-κß and associated cytokines among exposed cells suggested the activation of NF-κß mediated inflammatory loop which potentially serves as a platform for initiating epigenetic insinuations. This fact was strongly supported by the altered miRNA expression profile of the ultrafine PM exposed cells. These NF-κß induced miRNA alterations were also found to be associated with other epigenetic targets as the exposed cells showed higher expression levels of DNA methyltransferases which positively corresponded with the global changes in DNA methylation levels. Upon further analysis, significant alterations in histone code were also reported in ultrafine PM exposed cells. Conclusively our results suggested that NF-κß acts as an inflammatory switch that possesses the potential to induce genome-wide epigenetic modification upon ultrafine PM exposure.


Assuntos
Metilação de DNA/efeitos dos fármacos , Epigênese Genética/genética , Linfócitos/metabolismo , NF-kappa B/metabolismo , Material Particulado/toxicidade , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Dano ao DNA/efeitos dos fármacos , Metilases de Modificação do DNA/biossíntese , Humanos , MicroRNAs/biossíntese , MicroRNAs/genética , Mitocôndrias/genética , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/fisiologia , Tamanho da Partícula , Material Particulado/análise , Fosfatidilinositol 3-Quinase/metabolismo , Espécies Reativas de Oxigênio/metabolismo
18.
Ecotoxicol Environ Saf ; 179: 175-181, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31039460

RESUMO

DNA methylation (5-mc) is one of the several epigenetic markers, and is generally associated with the inhibition of gene expression. Both hyper and hypo DNA methylation are associated with the diseases. Exposure to fine particles with a diameter of 2.5 µm or less (PM2.5) is a pervasive risk factor for cardiopulmonary mortality, metabolic disorders, cognition damage, and etc.. Recent reports pointed toward that these diseases were associated with the altered DNA methylation level of some specific-gene, potentially suggesting that the DNA methylation alteration was involved in the health hazard derived from the PM2.5 exposure. In this study, we systematically investigated the global DNA methylation level of most tissues, including lung, heart, testis, thymus, spleen, epididymal fat, hippocampus, kidney, live, after short and long term PM2.5 exposure. After acute PM2.5 exposure, the global hypo-methylation in DNA was observed in lung and heart. Notably, after chronic PM2.5 exposure, level of global DNA methylation decreased in most organs which included lung, testis, thymus, spleen, epididymal fat, hippocampus and blood. The present study systematically demonstrated the global DNA methylation changes by PM2.5 exposure, and put forward a possible orientation for further exploring the effects of ambient air particles exposure on the specific organs.


Assuntos
Poluentes Atmosféricos/toxicidade , Metilação de DNA/efeitos dos fármacos , Exposição por Inalação/efeitos adversos , Pulmão/efeitos dos fármacos , Material Particulado/toxicidade , Poluentes Atmosféricos/análise , Animais , DNA (Citosina-5-)-Metiltransferases/genética , Relação Dose-Resposta a Droga , Expressão Gênica/efeitos dos fármacos , Humanos , Pulmão/metabolismo , Pulmão/patologia , Masculino , Camundongos Endogâmicos C57BL , Especificidade de Órgãos , Tamanho da Partícula , Material Particulado/análise
19.
Cell Mol Life Sci ; 76(21): 4341-4354, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31119300

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is a metabolic liver disease that is thought to be reversible by changing the diet. To examine the impact of dietary changes on progression and cure of NAFLD, we fed mice a high-fat diet (HFD) or high-fructose diet (HFrD) for 9 weeks, followed by an additional 9 weeks, where mice were given normal chow diet. As predicted, the diet-induced NAFLD elicited changes in glucose tolerance, serum cholesterol, and triglyceride levels in both diet groups. Moreover, the diet-induced NAFLD phenotype was reversed, as measured by the recovery of glucose intolerance and high cholesterol levels when mice were given normal chow diet. However, surprisingly, the elevated serum triglyceride levels persisted. Metagenomic analysis revealed dietary-induced changes of microbiome composition, some of which remained altered even after reversing the diet to normal chow, as illustrated by species of the Odoribacter genus. Genome-wide DNA methylation analysis revealed a "priming effect" through changes in DNA methylation in key liver genes. For example, the lipid-regulating gene Apoa4 remained hypomethylated in both groups even after introduction to normal chow diet. Our results support that dietary change, in part, reverses the NAFLD phenotype. However, some diet-induced effects remain, such as changes in microbiome composition, elevated serum triglyceride levels, and hypomethylation of key liver genes. While the results are correlative in nature, it is tempting to speculate that the dietary-induced changes in microbiome composition may in part contribute to the persistent epigenetic modifications in the liver.


Assuntos
Metilação de DNA , Dieta Hiperlipídica/efeitos adversos , Microbioma Gastrointestinal , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/etiologia , Animais , Metilação de DNA/efeitos dos fármacos , Gorduras na Dieta/efeitos adversos , Gorduras na Dieta/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Fígado/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/microbiologia , Obesidade/genética , Obesidade/metabolismo , Obesidade/microbiologia
20.
Anticancer Res ; 39(5): 2395-2403, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31092432

RESUMO

BACKGROUND/AIM: During cancer progression cells undergo epithelial-to-mesenchymal transition (EMT). Although EMT is a complex process, recently, it has been reported that CD146 overexpression in prostate cancer cells is sufficient to induce mesenchymal phenotype. The following study aimed to investigate whether the expression of CD146 is altered by an epigenetic modifier in prostate cancer cells, in vitro. MATERIALS AND METHODS: Three human prostate cancer cell lines were treated with 5-aza-2-deoxycytidine; the expression of CD146 and EMT-related factors was analyzed by RT-PCR and western Blot. The methylation status of the CD146 promoter area was assessed using bisulfite sequencing. RESULTS: Our data showed that, the expression of CD146 was evidently increased in all three studied cell lines in response to a demethylating agent, both at the mRNA and protein level, suggesting epigenetic regulation of the analyzed gene. However, there was no methylation in the studied CpG island in CD146 gene promoter. Moreover, the demethylating agent induced the expression of EMT-related transcription factors (SNAI1, SNAI2, TWIST1 and ZEB1), the pattern of which differed among the cell lines, as well as alterations in cell morphology; altogether accounting for the mesenchymal phenotype. CONCLUSION: The demethylating agent 5-aza-2-deoxycytidine triggers the expression of CD146 in prostate cancer cells independently on the methylation status of the analyzed CpG island fragment in CD146 gene promoter. Moreover, demethylation treatment induces a mesenchymal profile in prostate cancer cells.


Assuntos
Metilação de DNA/genética , Decitabina/farmacologia , Neoplasias da Próstata/genética , Antígeno CD146/genética , Linhagem Celular Tumoral , Metilação de DNA/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Regiões Promotoras Genéticas/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Próstata/metabolismo , Próstata/patologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA