RESUMEN
The mechanisms underlying the sustained activation of the PI3K/AKT and Wnt/ß-catenin pathways mediated by HOTAIR in cervical cancer (CC) have not been extensively described. To address this knowledge gap in the literature, we explored the interactions between these pathways by driving HOTAIR expression levels in HeLa cells. Our findings reveal that HOTAIR is a key regulator in sustaining the activation of both signaling pathways. Specifically, altering HOTAIR expression-either by knockdown or overexpression-significantly influenced the transcriptional activity of the PI3K/AKT and Wnt/ß-catenin pathways. Additionally, we discovered that HIF1α directly induces HOTAIR transcription, which in turn leads to the epigenetic silencing of the PTEN promoter via DNMT1. This process leads to the sustained activation of both pathways, highlighting a novel regulatory axis involving HOTAIR and HIF1α in cervical cancer. Our results suggest a new model in which HOTAIR sustains reciprocal activation of the PI3K/AKT and Wnt/ß-catenin pathways through the HOTAIR/HIF1α axis, thereby contributing to the oncogenic phenotype of cervical cancer.
Asunto(s)
Metilación de ADN , Subunidad alfa del Factor 1 Inducible por Hipoxia , Fosfohidrolasa PTEN , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , ARN Largo no Codificante , Neoplasias del Cuello Uterino , Vía de Señalización Wnt , Humanos , Neoplasias del Cuello Uterino/genética , Neoplasias del Cuello Uterino/metabolismo , Neoplasias del Cuello Uterino/patología , Femenino , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Fosfohidrolasa PTEN/metabolismo , Fosfohidrolasa PTEN/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Vía de Señalización Wnt/genética , Células HeLa , Metilación de ADN/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Regulación Neoplásica de la Expresión Génica , beta Catenina/metabolismo , beta Catenina/genética , Regiones Promotoras Genéticas/genética , ADN (Citosina-5-)-Metiltransferasa 1/metabolismo , ADN (Citosina-5-)-Metiltransferasa 1/genéticaRESUMEN
Designing and developing inhibitors against the epigenetic target DNA methyltransferase (DNMT) is an attractive strategy in epigenetic drug discovery. DNMT1 is one of the epigenetic enzymes with significant clinical relevance. Structure-based de novo design is a drug discovery strategy that was used in combination with similarity searching to identify a novel DNMT inhibitor with a novel chemical scaffold and warrants further exploration. This study aimed to continue exploring the potential of de novo design to build epigenetic-focused libraries targeted toward DNMT1. Herein, we report the results of an in-depth and critical comparison of ligand- and structure-based de novo design of screening libraries focused on DNMT1. The newly designed chemical libraries focused on DNMT1 are freely available on GitHub.
Asunto(s)
ADN (Citosina-5-)-Metiltransferasa 1 , Diseño de Fármacos , Inhibidores Enzimáticos , Ligandos , ADN (Citosina-5-)-Metiltransferasa 1/antagonistas & inhibidores , ADN (Citosina-5-)-Metiltransferasa 1/metabolismo , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Humanos , Bibliotecas de Moléculas Pequeñas/farmacología , Bibliotecas de Moléculas Pequeñas/química , Relación Estructura-ActividadRESUMEN
Hepatocellular carcinoma (HCC) development is associated with altered modifications in DNA methylation, changing transcriptional regulation. Emerging evidence indicates that DNA methyltransferase 1 (DNMT1) plays a key role in the carcinogenesis process. This study aimed to investigate how pirfenidone (PFD) modifies this pathway and the effect generated by the association between c-Myc expression and DNMT1 activation. Rats F344 were used for HCC development using 50 mg/kg of diethylnitrosamine (DEN) and 25 mg/kg of 2-Acetylaminofluorene (2-AAF). The HCC/PFD group received simultaneous doses of 300 mg/kg of PFD. All treatments lasted 12 weeks. On the other hand, HepG2 cells were used to evaluate the effects of PFD in restoring DNA methylation in the presence of the inhibitor 5-Aza. Histopathological, biochemical, immunohistochemical, and western blot analysis were carried out and our findings showed that PFD treatment reduced the amount and size of tumors along with decreased Glipican-3, ß-catenin, and c-Myc expression in nuclear fractions. Also, this treatment improved lipid metabolism by modulating PPARγ and SREBP1 signaling. Interestingly, PFD augmented DNMT1 and DNMT3a protein expression, which restores global methylation, both in our in vivo and in vitro models. In conclusion, our results suggest that PFD could slow down HCC development by controlling DNA methylation.
Asunto(s)
Carcinoma Hepatocelular , ADN (Citosina-5-)-Metiltransferasa 1 , Metilación de ADN , Antígeno Nuclear de Célula en Proliferación , Piridonas , Animales , ADN (Citosina-5-)-Metiltransferasa 1/metabolismo , ADN (Citosina-5-)-Metiltransferasa 1/genética , Metilación de ADN/efectos de los fármacos , Metilación de ADN/genética , Piridonas/farmacología , Ratas , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Humanos , Células Hep G2 , Antígeno Nuclear de Célula en Proliferación/metabolismo , Masculino , Ratas Endogámicas F344 , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Dietilnitrosamina , Neoplasias Hepáticas Experimentales/tratamiento farmacológico , Neoplasias Hepáticas Experimentales/patología , Neoplasias Hepáticas Experimentales/metabolismo , Neoplasias Hepáticas Experimentales/genéticaRESUMEN
Phenolic acids represent a large collection of phytochemical molecules present in the plant kingdom; they have an important role as epigenetic regulators, particularly as inhibitors of DNA methylation. In the present study, 14 methyl benzoate and cinnamate analogs were synthesized (11-24). Their cytotoxic activity on hepatocellular carcinoma cells (Hep3B) and immortalized human hepatocyte cells was then evaluated. In addition, its effect on the inhibition of global DNA methylation in Hep3B was also determined. Our results showed that the cinnamic derivatives 11-14 and 20-22 were more potent than the free caffeic acid (IC50 109.7-364.2 µM), being methyl 3,4-dihydroxycinammate (12) the most active with an IC50 = 109.7 ± 0.8 µM. Furthermore, 11-14, 20-23 compounds decreased overall DNA methylation levels by 63% to 97%. The analogs methyl 4-hydroxycinnamate (11), methyl 3,4,5-trimethoxycinnamate (14), methyl 4-methoxycinnamate (21), and methyl 3,4-dimethoxycinnamate (22) showed relevant activities of both cytotoxicity and global DNA methylation inhibition. The molecular docking of 21 and 14 suggested that they partly bind to the SAH-binding pocket of DNA methyltransferase 1. These results emphasize the importance of natural products and their analogs as potential sources of DNA methylation modulating agents.
Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Benzoatos , Carcinoma Hepatocelular/tratamiento farmacológico , Línea Celular Tumoral , Cinamatos/farmacología , ADN (Citosina-5-)-Metiltransferasa 1/metabolismo , Metilación de ADN , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Simulación del Acoplamiento MolecularRESUMEN
BACKGROUND: Peroxisome proliferator-activated receptor alpha (PPARα) is associated with diabetic retinopathy (DR), and the underlying mechanism is still unclear. Aim of this work was to investigate the mechanism of PPARα in DR. METHODS: Human retinal capillary pericytes (HRCPs) were treated with high glucose (HG) to induce DR cell model. DR mouse model was established by streptozotocin injection, and then received 5-Aza-2-deoxycytidine (DAC; DNA methyltransferase inhibitor) treatment. Hematoxylin-eosin staining was performed to assess retinal tissue damage. PPARα methylation was examined by Methylation-Specific PCR. Flow cytometry and DCFH-DA fluorescent probe was used to estimate apoptosis and reactive oxygen species (ROS). The interaction between DNA methyltransferase-1 (DNMT1) and PPARα promoter was examined by Chromatin Immunoprecipitation. Quantitative real-time PCR and western blot were performed to assess gene and protein expression. RESULTS: HG treatment enhanced the methylation levels of PPARα, and repressed PPARα expression in HRCPs. The levels of apoptotic cells and ROS were significantly increased in HRCPs in the presence of HG. Moreover, DNMT1 was highly expressed in HG-treated HRCPs, and DNMT1 interacted with PPARα promoter. PPARα overexpression suppressed apoptosis and ROS levels of HRCPs, which was rescued by DNMT1 up-regulation. In DR mice, DAC treatment inhibited PPARα methylation and reduced damage of retinal tissues. CONCLUSION: DNMT1-mediated PPARα methylation promotes apoptosis and ROS levels of HRCPs and aggravates damage of retinal tissues in DR mice. Thus, this study may highlight novel insights into DR pathogenesis.
Asunto(s)
ADN (Citosina-5-)-Metiltransferasa 1/metabolismo , Retinopatía Diabética , PPAR alfa/genética , Retina/patología , Animales , Apoptosis , Células Cultivadas , Metilación de ADN , Diabetes Mellitus , Modelos Animales de Enfermedad , Humanos , Metilación , Ratones , Regiones Promotoras Genéticas , Retina/citologíaRESUMEN
Periodontal ligament cells (PDLCs) have well documented osteogenic potential; however, this commitment can be highly heterogenous, limiting their applications in tissue regeneration. In this study, we use PDLC populations characterized by high and low osteogenic potential (h-PDLCs and l-PDLCs, respectively) to identify possible sources of such heterogeneity and to investigate whether the osteogenic differentiation can be enhanced by epigenetic modulation. In h-PDLCs, low basal expression levels of pluripotency markers (NANOG, OCT4), DNA methyltransferases (DNMT1, DNMT3B), and enzymes involved in active DNA demethylation (TET1, TET3) were prerequisite to high osteogenic potential. Furthermore, these genes were downregulated upon early osteogenesis, possibly allowing for the increase in expression of the key osteogenic transcription factors, Runt-related transcription factor 2 (RUNX2) and SP7, and ultimately, mineral nodule formation. l-PDLCs appeared locked in the multipotent state and this was further enhanced upon early osteogenic stimulation, correlating with low RUNX2 expression and impaired mineralization. Further upregulation of DNMTs was also evident, while pretreatment with RG108, the DNMTs' inhibitor, enhanced the osteogenic program in l-PDLCs through downregulation of DNMTs, increased RUNX2 expression and nuclear localization, accelerated expression of osteogenic markers, and increased mineralization. These findings point toward the role of DNMTs and Ten Eleven Translocations (TETs) in osteogenic commitment and support application of epigenetic approaches to modulate biomineralization in PDLCs.
Asunto(s)
Calcificación Fisiológica , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , ADN (Citosina-5-)-Metiltransferasa 1/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Ligamento Periodontal/citología , Calcificación Fisiológica/efectos de los fármacos , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , ADN (Citosina-5-)-Metiltransferasa 1/metabolismo , Regulación hacia Abajo/efectos de los fármacos , Humanos , Osteogénesis/genética , Ftalimidas/farmacología , Triptófano/análogos & derivados , Triptófano/farmacología , Regulación hacia Arriba/efectos de los fármacos , Adulto JovenRESUMEN
BACKGROUND: Peroxisome proliferator-activated receptor alpha (PPARα) is associated with diabetic retinopathy (DR), and the underlying mechanism is still unclear. Aim of this work was to investigate the mechanism of PPARα in DR. METHODS: Human retinal capillary pericytes (HRCPs) were treated with high glucose (HG) to induce DR cell model. DR mouse model was established by streptozotocin injection, and then received 5-Aza-2-deoxycytidine (DAC; DNA methyltransferase inhibitor) treatment. Hematoxylin-eosin staining was performed to assess retinal tissue damage. PPARα methylation was examined by Methylation-Specific PCR. Flow cytometry and DCFH-DA fluorescent probe was used to estimate apoptosis and reactive oxygen species (ROS). The interaction between DNA methyltransferase-1 (DNMT1) and PPARα promoter was examined by Chromatin Immunoprecipitation. Quantitative real-time PCR and western blot were performed to assess gene and protein expression. RESULTS: HG treatment enhanced the methylation levels of PPARα, and repressed PPARα expression in HRCPs. The levels of apoptotic cells and ROS were significantly increased in HRCPs in the presence of HG. Moreover, DNMT1 was highly expressed in HG-treated HRCPs, and DNMT1 interacted with PPARα promoter. PPARα overexpression suppressed apoptosis and ROS levels of HRCPs, which was rescued by DNMT1 up-regulation. In DR mice, DAC treatment inhibited PPARα methylation and reduced damage of retinal tissues. CONCLUSION: DNMT1-mediated PPARα methylation promotes apoptosis and ROS levels of HRCPs and aggravates damage of retinal tissues in DR mice. Thus, this study may highlight novel insights into DR pathogenesis.
Asunto(s)
Humanos , Animales , Ratones , Retina/patología , PPAR alfa/genética , Retinopatía Diabética , ADN (Citosina-5-)-Metiltransferasa 1/metabolismo , Retina/citología , Células Cultivadas , Regiones Promotoras Genéticas , Apoptosis , Metilación de ADN , Diabetes Mellitus , Modelos Animales de Enfermedad , MetilaciónRESUMEN
DNA methyltransferases (DNMTs) play an essential role in DNA methylation and transcriptional regulation in the genome. DNMTs, along with other poorly studied elements, modulate the dynamic DNA methylation patterns of embryonic and adult cells. We summarize the current knowledge on the molecular mechanism of DNMTs' functional targeting to maintain genome-wide DNA methylation patterns. We focus on DNMTs' intrinsic characteristics, transcriptional regulation, and post-transcriptional modifications. Furthermore, we focus special attention on the DNMTs' specificity for target sites, including key cis-regulatory factors such as CpG content, common motifs, transcription factors (TF) binding sites, lncRNAs, and histone marks to regulate DNA methylation. We also review how complexes of DNMTs/TFs or DNMTs/lncRNAs are involved in DNA methylation in specific genome regions. Understanding these processes is essential because the spatiotemporal regulation of DNA methylation modulates gene expression in health and disease.
Asunto(s)
Metilación de ADN , Metilasas de Modificación del ADN/genética , Código de Histonas/genética , ARN Largo no Codificante/genética , Factores de Transcripción/genética , 5-Metilcitosina/metabolismo , Animales , Islas de CpG , ADN (Citosina-5-)-Metiltransferasa 1/genética , ADN (Citosina-5-)-Metiltransferasa 1/metabolismo , Metilasas de Modificación del ADN/metabolismo , Humanos , Regiones Promotoras GenéticasRESUMEN
A common characteristic of cancer types associated with viruses is the dysregulated expression of the CDH1 gene, which encodes Ecadherin, in general by activation of DNA methyltransferases (Dnmts). In cervical cancer, E7 protein from high risk human papillomaviruses (HPVs) has been demonstrated to interact with Dnmt1 and histone deacetylase type 1 (HDAC1). The present study proposed that E7 may regulate the expression of CDH1 through two pathways: i) Epigenetic, including DNA methylation; and ii) Epigeneticindependent, including the induction of negative regulators of CDH1 expression, such as Snail family transcriptional repressor Snai1 and Snai2. To test this hypothesis, HPV16 and HPV18positive cell lines were used to determine the methylation pattern of the CDH1 promoter and its expression in association with its negative regulators. Different methylation frequencies were identified in the CDH1 promoter in HeLa (88.24%) compared with SiHa (17.65%) and Ca Ski (0%) cell lines. Significant differences in the expression of SNAI1 were observed between these cell lines, and an inverse association was identified between the expression levels of SNAI1 and CDH1. In addition, suppressing E7 not only increased the expression of CDH1, but notably decreased the expression of SNAI1 and modified the methylation pattern of the CDH1 promoter. These results suggested that the expression of CDH1 was dependent on the expression of SNAI1 and was inversely associated with the expression of E7. The present results indicated that E7 from HPV16/18 regulated the expression of CDH1 by the two following pathways in which Snai1 is involved: i) Hypermethylation of the CDH1 promoter region and increasing expression of SNAI1, as observed in HeLa; and ii) Hypomethylation of the CDH1 promoter region and expression of SNAI1, as observed in SiHa. Therefore, the suppression of CDH1 and expression of SNAI1 may be considered to be biomarkers of metastasis in uterine cervical cancer.
Asunto(s)
Antígenos CD/genética , Cadherinas/genética , Proteínas de Unión al ADN/metabolismo , Regulación Neoplásica de la Expresión Génica , Proteínas Oncogénicas Virales/metabolismo , Proteínas E7 de Papillomavirus/metabolismo , Infecciones por Papillomavirus/genética , Factores de Transcripción de la Familia Snail/genética , Neoplasias del Cuello Uterino/genética , ADN (Citosina-5-)-Metiltransferasa 1/metabolismo , Metilación de ADN , Epigénesis Genética , Femenino , Células HeLa , Histona Desacetilasa 1/metabolismo , Interacciones Microbiota-Huesped/genética , Humanos , Infecciones por Papillomavirus/patología , Infecciones por Papillomavirus/virología , Regiones Promotoras Genéticas/genética , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/virologíaRESUMEN
Oral lichen planus (OLP) is an autoimmune inflammatory disease mediated by T cells, in whose pathogenesis CD4+ T helper cells are supposed to play vital roles. MiR-29b has recently been recognized as a crucial regulator in immune response and inflammation. The current research focuses on exploring how miR-29b functions in the immunopathogenesis of OLP. Our findings showed that miR-29b expression in CD4+ T cells was upregulated in OLP, especially in its erosive form. MiR-29b in CD4+ T cells repressed IFN-γ mRNA and IFN-γ secretion, but not T-bet and EOMES; in turn, IFN-γ increased the expression of STAT1 and miR-29b in CD4+ T cells. Moreover, miR-29b in CD4+ T cells suppressed DNMT1 expression and induced global DNA hypomethylation. In conclusion, elevated miR-29b interacts with IFN-γ via a regulatory feedback loop and induces global DNA hypomethylation in CD4+ T cells, which consequently modulates Type 1 T helper immune response, thus contributing to the immune dysregulation of OLP.
Asunto(s)
Linfocitos T CD4-Positivos/citología , Metilación de ADN , Interferón gamma/metabolismo , Liquen Plano Oral/inmunología , Liquen Plano Oral/metabolismo , MicroARNs/genética , Adulto , Proliferación Celular , ADN (Citosina-5-)-Metiltransferasa 1/metabolismo , Retroalimentación Fisiológica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Transfección , Adulto JovenRESUMEN
BACKGROUND: In the present study, we investigated the molecular mechanisms underlying the pro-apoptotic effects of quercetin (Qu) by evaluating the effect of Qu treatment on DNA methylation and posttranslational histone modifications of genes related to the apoptosis pathway. This study was performed in vivo in two human xenograft acute myeloid leukemia (AML) models and in vitro using HL60 and U937 cell lines. RESULTS: Qu treatment almost eliminates DNMT1 and DNMT3a expression, and this regulation was in part STAT-3 dependent. The treatment also downregulated class I HDACs. Furthermore, treatment of the cell lines with the proteasome inhibitor, MG132, together with Qu prevented degradation of class I HDACs compared to cells treated with Qu alone, indicating increased proteasome degradation of class I HDACS by Qu. Qu induced demethylation of the pro-apoptotic BCL2L11, DAPK1 genes, in a dose- and time-dependent manner. Moreover, Qu (50 µmol/L) treatment of cell lines for 48 h caused accumulation of acetylated histone 3 and histone 4, resulting in three- to ten fold increases in the promoter region of DAPK1, BCL2L11, BAX, APAF1, BNIP3, and BNIP3L. In addition, Qu treatment significantly increased the mRNA levels of all these genes, when compared to cells treated with vehicle only (control cells) (*p < 0.05). CONCLUSIONS: In summary, our results showed that enhanced apoptosis, induced by Qu, might be caused in part by its DNA demethylating activity, by HDAC inhibition, and by the enrichment of H3ac and H4ac in the promoter regions of genes involved in the apoptosis pathway, leading to their transcription activation.
Asunto(s)
ADN (Citosina-5-)-Metiltransferasa 1/metabolismo , ADN (Citosina-5-)-Metiltransferasas/metabolismo , Metilación de ADN/efectos de los fármacos , Leucemia Mieloide Aguda/tratamiento farmacológico , Leupeptinas/administración & dosificación , Quercetina/administración & dosificación , Animales , ADN Metiltransferasa 3A , Regulación hacia Abajo , Sinergismo Farmacológico , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células HL-60 , Código de Histonas/efectos de los fármacos , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leupeptinas/farmacología , Ratones , Regiones Promotoras Genéticas/efectos de los fármacos , Quercetina/farmacología , Células U937 , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Type 2 diabetes mellitus (T2DM) is characterized by the inability of the insulin-producing ß-cells to overcome insulin resistance. We previously identified an imprinted region on chromosome 14, the DLK1-MEG3 locus, as being downregulated in islets from humans with T2DM. In this study, using targeted epigenetic modifiers, we prove that increased methylation at the promoter of Meg3 in mouse ßTC6 ß-cells results in decreased transcription of the maternal transcripts associated with this locus. As a result, the sensitivity of ß-cells to cytokine-mediated oxidative stress was increased. Additionally, we demonstrate that an evolutionarily conserved intronic region at the MEG3 locus can function as an enhancer in ßTC6 ß-cells. Using circular chromosome conformation capture followed by high-throughput sequencing, we demonstrate that the promoter of MEG3 physically interacts with this novel enhancer and other putative regulatory elements in this imprinted region in human islets. Remarkably, this enhancer is bound in an allele-specific manner by the transcription factors FOXA2, PDX1, and NKX2.2. Overall, these data suggest that the intronic MEG3 enhancer plays an important role in the regulation of allele-specific expression at the imprinted DLK1-MEG3 locus in human ß-cells, which in turn impacts the sensitivity of ß-cells to cytokine-mediated oxidative stress.
Asunto(s)
Metilación de ADN , Diabetes Mellitus Tipo 2/metabolismo , Regulación de la Expresión Génica , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Islotes Pancreáticos/metabolismo , Proteínas de la Membrana/metabolismo , Regiones Promotoras Genéticas , ARN Largo no Codificante/metabolismo , Animales , Proteínas de Unión al Calcio , Línea Celular , Citocinas/metabolismo , ADN (Citosina-5-)-Metiltransferasa 1/química , ADN (Citosina-5-)-Metiltransferasa 1/genética , ADN (Citosina-5-)-Metiltransferasa 1/metabolismo , Diabetes Mellitus Tipo 2/patología , Elementos de Facilitación Genéticos , Epigénesis Genética , Sitios Genéticos , Proteínas Fluorescentes Verdes/química , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Proteína Homeobox Nkx-2.2 , Proteínas de Homeodominio/química , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Humanos , Péptidos y Proteínas de Señalización Intercelular/genética , Islotes Pancreáticos/patología , Región de Control de Posición , Proteínas de la Membrana/genética , Ratones , Mutación , Proteínas Nucleares , Estrés Oxidativo/efectos de los fármacos , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/metabolismo , Proteínas Represoras/química , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Bancos de Tejidos , Factores de Transcripción/genética , Factores de Transcripción/metabolismoRESUMEN
Here, we determined the 5-hydroxymethylcytosine (5hmC), 5-methylcytosine (5mC), Ten Eleven Translocation (TETs), and DNA methyltransferases (DNMTs) levels in epithelial and inflammatory cells of labial salivary glands (LSG) from Sjögren's syndrome (SS)-patients and the effect of cytokines on HSG cells. LSG from SS-patients, controls and HSG cells incubated with cytokines were analysed. Levels of 5mC, 5hmC, DNMTs, TET2 and MeCP2 were assessed by immunofluorescence. In epithelial cells from SS-patients, an increase in TET2, 5hmC and a decrease in 5mC and MeCP2 were observed, additionally, high levels of 5mC and DNMTs and low levels of 5hmC were detected in inflammatory cells. Cytokines increased TET2 and 5hmC and decreased 5mC levels. Considering that the TET2 gene.promoter contains response elements for transcription factors activated by cytokines, together to in vitro results suggest that changes in DNA hydroxymethylation, resulting from altered levels of TET2 are likely to be relevant in the Sjögren's syndrome etiopathogenesis.
Asunto(s)
5-Metilcitosina/análogos & derivados , ADN (Citosina-5-)-Metiltransferasas/genética , Proteínas de Unión al ADN/genética , Proteína 2 de Unión a Metil-CpG/genética , Proteínas Proto-Oncogénicas/genética , Glándulas Salivales Menores/metabolismo , Síndrome de Sjögren/genética , 5-Metilcitosina/metabolismo , Adulto , Anciano , Citidina Desaminasa/genética , Citidina Desaminasa/metabolismo , Citocinas/inmunología , ADN (Citosina-5-)-Metiltransferasa 1/genética , ADN (Citosina-5-)-Metiltransferasa 1/metabolismo , ADN (Citosina-5-)-Metiltransferasas/metabolismo , Metilación de ADN , ADN Metiltransferasa 3A , Proteínas de Unión al ADN/inmunología , Proteínas de Unión al ADN/metabolismo , Dioxigenasas/genética , Dioxigenasas/inmunología , Dioxigenasas/metabolismo , Epigénesis Genética , Femenino , Expresión Génica , Regulación de la Expresión Génica , Humanos , Inflamación/genética , Inflamación/metabolismo , Labio , Masculino , Proteína 2 de Unión a Metil-CpG/metabolismo , Persona de Mediana Edad , Oxigenasas de Función Mixta/genética , Oxigenasas de Función Mixta/inmunología , Oxigenasas de Función Mixta/metabolismo , Regiones Promotoras Genéticas , Proteínas Proto-Oncogénicas/inmunología , Proteínas Proto-Oncogénicas/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Glándulas Salivales Menores/citología , Glándulas Salivales Menores/inmunología , Síndrome de Sjögren/inmunología , Síndrome de Sjögren/metabolismo , Adulto Joven , ADN Metiltransferasa 3BRESUMEN
Stress in early life has been appointed as an important phenomenon in the onset of depression and poor response to treatment with classical antidepressants. Furthermore, childhood trauma triggers epigenetic changes, which are associated with the pathophysiology of major depressive disorder (MDD). Treatment with atypical antipsychotics such as quetiapine, exerts therapeutic effect for MDD patients and induces epigenetic changes. This study aimed to analyze the effect of chronic treatment with quetiapine (20mg/kg) on depressive-like behavior of rats submitted to maternal deprivation (MD), as well as the activity of histone acetylation by the enzymes histone acetyl transferases (HAT) and deacetylases (HDAC) and DNA methylation, through DNA methyltransferase enzyme (DNMT) in the prefrontal cortex (PFC), nucleus accumbens (NAc) and hippocampus. Maternally deprived rats had a depressive-like behavior in the forced swimming test and an increase in the HDAC and DNMT activities in the hippocampus and NAc. Treatment with quetiapine reversed depressive-like behavior and reduced the DNMT activity in the hippocampus. This is the first study to show the antidepressant-like effect of quetiapine in animals subjected to MD and a protective effect by quetiapine in reducing epigenetic changes induced by stress in early life. These results reinforce an important role of quetiapine as therapy for MDD.
Asunto(s)
Antidepresivos/uso terapéutico , Trastornos de Ansiedad/tratamiento farmacológico , ADN (Citosina-5-)-Metiltransferasa 1/metabolismo , Metilación de ADN/efectos de los fármacos , Privación Materna , Fumarato de Quetiapina/uso terapéutico , Análisis de Varianza , Animales , Trastornos de Ansiedad/etiología , Encéfalo/efectos de los fármacos , Encéfalo/enzimología , Conducta Exploratoria/efectos de los fármacos , Femenino , Histona Acetiltransferasas/metabolismo , Histona Desacetilasas/metabolismo , Pérdida de Tono Postural/efectos de los fármacos , Masculino , Embarazo , Ratas , Ratas Wistar , Natación/psicologíaRESUMEN
Some studies have linked age-related beneficial effects of exercise and epigenetic mechanisms. Although, the impact of treadmill exercise on histone acetylation, histone and DNA methylation marks in aged cortices yet remains poorly understood. Considering the role of frontal cortex on brain functions, we investigated the potential of different exercise protocols, single session and daily exercise, to modulate epigenetic marks, namely global H4 acetylation, histone methyltransferase activity (HMT H3K27) and levels of DNA methytransferase (DNMT1 and DNMT3b) in prefrontal cortices from 3 and 21-months aged Wistar rats. The animals were submitted to two treadmill exercise protocols, single session (20min) or daily moderate (20min/day during 14days). The daily exercise protocol induced an increased in histone H4 acetylation levels in prefrontal cortices of 21-months-old rats, without any effects in young adult group. DNMT3b levels were increased in aged cortices of animals submitted to single session of exercise. These results indicate that prefrontal cortex is susceptible to epigenetic changes in a protocol dependent-manner and that H4 acetylation levels and DNMT3b content changes might be linked at least in part to exercise-induced effects on brain functions.