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1.
Dig Med Res ; 72024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-39399394

RESUMEN

Histone post-translational modifications are reversible epigenetic mechanisms that regulate chromatin structure and gene transcription. In recent years, in addition to the well-characterized histone acetylation, new acylations such as propionylation, crotonylation, butyrylation and beta-hydroxybutyrylation have been described and explored in different cell types at contexts of health and disease. Understanding how histone acylations contribute to gene expression regulation is especially important in intestinal epithelial cells (IECs) because they receive many different signals from other cells and the external environment and must adapt to maintain essential functions such as nutrient and water absorption, maintenance of tolerance and protection against pathogens. In this review, we describe how cells regulate these modifications, how they are recognized by other proteins and impact gene expression. We summarize recent studies that explored the role of these distinct epigenetic marks in the regulation of IECs and discuss their biological importance for the intestinal epithelium's adaptations to changes in metabolism and to respond to environmental signals provided, for example, by the diet, components of the intestinal microbiota and pathogens. Finally, we discuss how the histone acylations are affected by inflammatory signals and how this knowledge may provide new targets for treatment of pathologies such as the inflammatory bowel diseases.

2.
J Exp Bot ; 75(19): 6159-6166, 2024 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-38769701

RESUMEN

Plants synchronize their growth and development with environmental changes, which is critical for their survival. Among their life cycle transitions, seed germination is key for ensuring the survival and optimal growth of the next generation. However, even under favorable conditions, often germination can be blocked by seed dormancy, a regulatory multilayered checkpoint integrating internal and external signals. Intricate genetic and epigenetic mechanisms underlie seed dormancy establishment, maintenance, and release. In this review, we focus on recent advances that shed light on the complex mechanisms associated with physiological dormancy, prevalent in seed plants, with Arabidopsis thaliana serving as a model. Here, we summarize the role of multiple epigenetic regulators, but with a focus on histone modifications such as acetylation and methylation, that finely tune dormancy responses and influence dormancy-associated gene expression. Understanding these mechanisms can lead to a better understanding of seed biology in general, as well as resulting in the identification of possible targets for breeding climate-resilient plants.


Asunto(s)
Arabidopsis , Epigénesis Genética , Histonas , Latencia en las Plantas , Procesamiento Proteico-Postraduccional , Arabidopsis/genética , Arabidopsis/fisiología , Arabidopsis/metabolismo , Arabidopsis/crecimiento & desarrollo , Latencia en las Plantas/genética , Histonas/metabolismo , Histonas/genética , Semillas/crecimiento & desarrollo , Semillas/genética , Semillas/fisiología , Semillas/metabolismo , Regulación de la Expresión Génica de las Plantas , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Germinación
3.
Epigenomics ; 16(6): 419-426, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38410929

RESUMEN

Neural tube defects (NTDs) are the most common congenital anomalies of the CNS. It is widely appreciated that both genetic and environmental factors contribute to their etiology. The inability to ascribe clear genetic patterns of inheritance to various NTD phenotypes suggests it is possible that epigenetic mechanisms are involved in the etiology of NTDs. In this context, the contribution of DNA methylation as an underlying contributing factor to the etiology of NTDs has been extensively reviewed. Here, an updated accounting of the evidence linking post-translational histone modifications to these birth defects, relying heavily upon studies in humans, and the possible molecular implications inferred from reports based on cellular and animal models, are presented.


Asunto(s)
Histonas , Defectos del Tubo Neural , Animales , Humanos , Histonas/metabolismo , Código de Histonas , Defectos del Tubo Neural/genética , Epigénesis Genética , Metilación de ADN
4.
Int J Mol Sci ; 24(13)2023 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-37446028

RESUMEN

Huntington's disease (HD) is a disorder caused by an abnormal expansion of trinucleotide CAG repeats within the huntingtin (Htt) gene. Under normal conditions, the CREB Binding Protein interacts with CREB elements and acetylates Lysine 27 of Histone 3 to direct the expression of several genes. However, mutant Htt causes depletion of CBP, which in turn induces altered histone acetylation patterns and transcriptional deregulation. Here, we have studied a differential expression analysis and H3K27ac variation in 4- and 6-week-old R6/2 mice as a model of juvenile HD. The analysis of differential gene expression and acetylation levels were integrated into Gene Regulatory Networks revealing key regulators involved in the altered transcription cascade. Our results show changes in acetylation and gene expression levels that are related to impaired neuronal development, and key regulators clearly defined in 6-week-old mice are proposed to drive the downstream regulatory cascade in HD. Here, we describe the first approach to determine the relationship among epigenetic changes in the early stages of HD. We determined the existence of changes in pre-symptomatic stages of HD as a starting point for early onset indicators of the progression of this disease.


Asunto(s)
Enfermedad de Huntington , Ratones , Animales , Enfermedad de Huntington/genética , Enfermedad de Huntington/metabolismo , Histonas/genética , Histonas/metabolismo , Acetilación , Modelos Animales de Enfermedad , Epigénesis Genética , Proteína Huntingtina/genética , Proteína Huntingtina/metabolismo
5.
Int J Mol Sci ; 24(10)2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-37240421

RESUMEN

Multiple sclerosis (MS) is a chronic disease affecting the central nervous system (CNS) due to an autoimmune attack on axonal myelin sheaths. Epigenetics is an open research topic on MS, which has been investigated in search of biomarkers and treatment targets for this heterogeneous disease. In this study, we quantified global levels of epigenetic marks using an ELISA-like approach in Peripheral Blood Mononuclear Cells (PBMCs) from 52 patients with MS, treated with Interferon beta (IFN-ß) and Glatiramer Acetate (GA) or untreated, and 30 healthy controls. We performed media comparisons and correlation analyses of these epigenetic markers with clinical variables in subgroups of patients and controls. We observed that DNA methylation (5-mC) decreased in treated patients compared with untreated and healthy controls. Moreover, 5-mC and hydroxymethylation (5-hmC) correlated with clinical variables. In contrast, histone H3 and H4 acetylation did not correlate with the disease variables considered. Globally quantified epigenetic DNA marks 5-mC and 5-hmC correlate with disease and were altered with treatment. However, to date, no biomarker has been identified that can predict the potential response to therapy before treatment initiation.


Asunto(s)
Esclerosis Múltiple Recurrente-Remitente , Esclerosis Múltiple , Humanos , Acetato de Glatiramer/uso terapéutico , Interferón beta/uso terapéutico , Leucocitos Mononucleares , Metilación de ADN , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico
6.
Cells ; 12(9)2023 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-37174649

RESUMEN

Diabetes mellitus (DM) is an important risk factor for dementia, which is a common neurodegenerative disorder. DM is known to activate inflammation, oxidative stress, and advanced glycation end products (AGEs) generation, all capable of inducing neuronal dysfunctions, thus participating in the neurodegeneration progress. In that process, disturbed neuronal glucose supply plays a key role, which in hippocampal neurons is controlled by the insulin-sensitive glucose transporter type 4 (GLUT4). We investigated the expression of GLUT4, nuclear factor NF-kappa B subunit p65 [NFKB (p65)], carboxymethyllysine and synapsin1 (immunohistochemistry), and soma area in human postmortem hippocampal samples from control, obese, and obese+DM subjects (41 subjects). Moreover, in human SH-SY5Y neurons, tumor necrosis factor (TNF) and glycated albumin (GA) effects were investigated in GLUT4, synapsin-1 (SYN1), tyrosine hydroxylase (TH), synaptophysin (SYP) proteins, and respective genes; NFKB binding activity in the SLC2A4 promoter; effects of increased histone acetylation grade by histone deacetylase 3 (HDAC3) inhibition. Hippocampal neurons (CA4 area) of obese+DM subjects displayed reduced GLUT4 expression and neuronal soma area, associated with increased expression of NFKB (p65). Challenges with TNF and GA decreased the SLC2A4/GLUT4 expression in SH-SY5Y neurons. TNF decreased SYN1, TH, and SYP mRNAs and respective proteins, and increased NFKB binding activity in the SLC2A4 promoter. Inhibition of HDAC3 increased the SLC2A4 expression and the total neuronal content of CRE-binding proteins (CREB/ICER), and also counterbalanced the repressor effect of TNF upon these parameters. This study revealed reduced postmortem human hippocampal GLUT4 content and neuronal soma area accompanied by increased proinflammatory activity in the brains of DM subjects. In isolated human neurons, inflammatory activation by TNF reduced not only the SLC2A4/GLUT4 expression but also the expression of some genes related to neuronal function (SYN1, TH, SYP). These effects may be related to epigenetic regulations (H3Kac and H4Kac status) since they can be counterbalanced by inhibiting HDAC3. These results uncover the improvement in GLUT4 expression and/or the inhibition of HDAC3 as promising therapeutic targets to fight DM-related neurodegeneration.


Asunto(s)
Diabetes Mellitus , Neuroblastoma , Humanos , Transportador de Glucosa de Tipo 4 , FN-kappa B/metabolismo , Inflamación , Neuronas/metabolismo , Obesidad
7.
J Funct Biomater ; 14(3)2023 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-36976051

RESUMEN

Cobalt-chromium (Co-Cr)-based alloys are emerging with important characteristics for use in dentistry, but the knowledge of epigenetic mechanisms in endothelial cells has barely been achieved. In order to address this issue, we have prepared a previously Co-Cr-enriched medium to further treat endothelial cells (HUVEC) for up to 72 h. Our data show there is important involvement with epigenetic machinery. Based on the data, it is believed that methylation balance in response to Co-Cr is finely modulated by DNMTs (DNA methyltransferases) and TETs (Tet methylcytosine dioxygenases), especially DNMT3B and both TET1 and TET2. Additionally, histone compaction HDAC6 (histone deacetylase 6) seems to develop a significant effect in endothelial cells. The requirement of SIRT1 seems to have a crucial role in this scenario. SIRT1 is associated with a capacity to modulate the expression of HIF-1α in response to hypoxia microenvironments, thus presenting a protective effect. As mentioned previously, cobalt is able to prevent HIF1A degradation and maintain hypoxia-related signaling in eukaryotic cells. Together, our results show, for the first time, a descriptive study reporting the relevance of epigenetic machinery in endothelial cells responding to cobalt-chromium, and it opens new perspectives to better understand their repercussions as prerequisites for driving cell adhesion, cell cycle progression, and angiogenesis surrounding this Co-Cr-based implantable device.

8.
Cell ; 185(12): 2057-2070.e15, 2022 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-35688133

RESUMEN

Spinal muscular atrophy (SMA) is a motor-neuron disease caused by mutations of the SMN1 gene. The human paralog SMN2, whose exon 7 (E7) is predominantly skipped, cannot compensate for the lack of SMN1. Nusinersen is an antisense oligonucleotide (ASO) that upregulates E7 inclusion and SMN protein levels by displacing the splicing repressors hnRNPA1/A2 from their target site in intron 7. We show that by promoting transcriptional elongation, the histone deacetylase inhibitor VPA cooperates with a nusinersen-like ASO to promote E7 inclusion. Surprisingly, the ASO promotes the deployment of the silencing histone mark H3K9me2 on the SMN2 gene, creating a roadblock to RNA polymerase II elongation that inhibits E7 inclusion. By removing the roadblock, VPA counteracts the chromatin effects of the ASO, resulting in higher E7 inclusion without large pleiotropic effects. Combined administration of the nusinersen-like ASO and VPA in SMA mice strongly synergizes SMN expression, growth, survival, and neuromuscular function.


Asunto(s)
Atrofia Muscular Espinal , Oligonucleótidos Antisentido , Animales , Cromatina , Exones , Ratones , Atrofia Muscular Espinal/tratamiento farmacológico , Atrofia Muscular Espinal/genética , Oligonucleótidos Antisentido/farmacología , Oligonucleótidos Antisentido/uso terapéutico , Empalme del ARN
9.
Neuroscience ; 497: 206-214, 2022 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-35314253

RESUMEN

Memories are initially labile and become stable through consolidation. Once consolidated, a memory can be destabilized by a reminder, requiring reconsolidation to become stable again. Memory reconsolidation has been evidenced in several learning tasks, including novel object recognition (NOR). But the features of the reminder that trigger memory destabilization and reconsolidation in this task are poorly characterized. Memory reconsolidation can be evidenced by delivering either an amnesic agent or a memory enhancer after reactivation and testing the resulting long-term memory alteration. Here we trained male mice for 15 min to induce a strong memory formation. Sulfasalazine, a specific inhibitor of the NF-κB pathway, was administered as an amnesic agent in the dorsal hippocampus. NF-κB is a key transcription factor required for consolidation and reconsolidation. We found that reconsolidation was induced when animals were re-exposed for 5 min to a combination of novel and familiar objects, but not to either two familiar or two novel objects. No destabilization was induced by re-exposure to the context without objects. Re-exposure to a combination of novel and familiar objects induced destabilization with a reactivation session as brief as 1 min. One minute of training induced a weak memory that could be enhanced by sodium butyrate, an inhibitor of histone deacetylases (HDACs), after 1 min of re-exposure. Histone acetylation is an epigenetic mechanism involved in gene expression regulation which positively correlates with memory. Thus, in this study we have performed an accurate characterization of the features of the reminder effective in triggering hippocampal NF-κB-dependent reconsolidation.


Asunto(s)
Consolidación de la Memoria , Memoria , Animales , Hipocampo/metabolismo , Aprendizaje , Masculino , Memoria/fisiología , Ratones , FN-kappa B/metabolismo , Sulfasalazina/farmacología
11.
Plant J ; 109(4): 873-890, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34807478

RESUMEN

Trichoderma atroviride is a root-colonizing fungus that confers multiple benefits to plants. In plants, small RNA (sRNA)-mediated gene silencing (sRNA-MGS) plays pivotal roles in growth, development, and pathogen attack. Here, we explored the role of core components of Arabidopsis thaliana sRNA-MGS pathways during its interaction with Trichoderma. Upon interaction with Trichoderma, sRNA-MGS-related genes paralleled the expression of Arabidopsis defense-related genes, linked to salicylic acid (SA) and jasmonic acid (JA) pathways. SA- and JA-related genes were primed by Trichoderma in leaves after the application of the well-known pathogen-associated molecular patterns flg22 and chitin, respectively. Defense-related genes were primed in roots as well, but to different extents and behaviors. Phenotypical characterization of mutants in AGO genes and components of the RNA-dependent DNA methylation (RdDM) pathway revealed that different sets of sRNA-MGS-related genes are essential for (i) the induction of systemic acquired resistance against Botrytis cinerea, (ii) the activation of the expression of plant defense-related genes, and (iii) root colonization by Trichoderma. Additionally, plant growth induced by Trichoderma depends on functional RdDM. Profiling of DNA methylation and histone N-tail modification patterns at the Arabidopsis Nitrile-Specifier Protein-4 (NSP4) locus, which is responsive to Trichoderma, showed altered epigenetic modifications in RdDM mutants. Furthermore, NSP4 is required for the induction of systemic acquired resistance against Botrytis and avoidance of enhanced root colonization by Trichoderma. Together, our results indicate that RdDM is essential in Arabidopsis to establish a beneficial relationship with Trichoderma. We propose that DNA methylation and histone modifications are required for plant priming by the beneficial fungus against B. cinerea.


Asunto(s)
Arabidopsis/genética , Arabidopsis/metabolismo , Resistencia a la Enfermedad/genética , Silenciador del Gen , Hypocreales/genética , Nitrilos/metabolismo , ARN/metabolismo , Proteínas de Arabidopsis/metabolismo , Botrytis , Ciclopentanos , Regulación de la Expresión Génica de las Plantas , Hypocreales/metabolismo , Oxilipinas , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/inmunología , Raíces de Plantas/metabolismo , Ácido Salicílico/metabolismo , Trichoderma/genética , Trichoderma/metabolismo
12.
Curr Neuropharmacol ; 20(3): 510-523, 2022 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-34279203

RESUMEN

Nicotine induces long-term changes in the neural activity of the mesocorticolimbic reward pathway structures. The mechanisms involved in this process have not been fully characterized. The hypothesis discussed here proposed that epigenetic regulation participates in the installation of persistent adaptations and long-lasting synaptic plasticity generated by nicotine action on the mesolimbic dopamine neurons of zebrafish. The epigenetic mechanisms induced by nicotine entail histone and DNA chemical modifications, which have been described to lead to changes in gene expression. Among the enzymes that catalyze epigenetic chemical modifications, histone deacetylases (HDACs) remove acetyl groups from histones, thereby facilitating DNA relaxation and making DNA more accessible to gene transcription. DNA methylation, which is dependent on DNA methyltransferase (DNMTs) activity, inhibits gene expression by recruiting several methyl binding proteins that prevent RNA polymerase binding to DNA. In zebrafish, phenylbutyrate (PhB), an HDAC inhibitor, abolishes nicotine rewarding properties together with a series of typical reward-associated behaviors. Furthermore, PhB and nicotine alter long- and short-term object recognition memory in zebrafish, respectively. Regarding DNA methylation effects, a methyl group donor L-methionine (L-met) was found to dramatically reduce nicotine-induced conditioned place preference (CPP) in zebrafish. Simultaneous treatment with DNMT inhibitor 5-aza-2'-deoxycytidine (AZA) was found to reverse the L-met effect on nicotine-induced CPP as well as nicotine reward-specific effects on genetic expression in zebrafish. Therefore, pharmacological interventions that modulate epigenetic regulation of gene expression should be considered as a potential therapeutic method to treat nicotine addiction.


Asunto(s)
Nicotina , Pez Cebra , Animales , Epigénesis Genética , Inhibidores de Histona Desacetilasas/farmacología , Nicotina/farmacología , Recompensa , Pez Cebra/genética
13.
Environ Pollut ; 286: 117296, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-33971473

RESUMEN

Bisphenol A (BPA) is an endocrine disrupting chemical able to promote hormone-responsive tumors. The major route of BPA contamination being oral, the aim of the present study was to investigate BPA effects on oral cells. Here, we evaluated the impact of sub-chronic in vivo exposure to BPA and its in vitro effects on neoplastic and non-neoplastic oral cells. We evaluated the oral mucosa of mice chronically exposed to BPA (200 mg/L). The response of keratinocytes (NOK-SI) and Head and Neck (HN) Squamous Cell Carcinoma (SCC), HN12 and HN13 cell lines to BPA was examined. In vivo, BPA accumulated in oral tissues and caused an increase in epithelial proliferative activity. BPA disrupted the function of keratinocytes by altering pro-survival and proliferative pathways and the secretion of cytokines and growth factors. In tumor cells, BPA induced proliferative, invasive, pro-angiogenic, and epigenetic paths. Our data highlight the harmful effects of BPA on oral mucosa and, tumorigenic and non-tumorigenic cells. Additionally, BPA may be a modifier of oral cancer cell behavior by prompting a functional shift to a more aggressive phenotype.


Asunto(s)
Disruptores Endocrinos , Neoplasias de la Boca , Animales , Compuestos de Bencidrilo/toxicidad , Disruptores Endocrinos/toxicidad , Ratones , Mucosa Bucal , Neoplasias de la Boca/inducido químicamente , Fenoles/toxicidad
14.
Acta Trop ; 217: 105872, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33639100

RESUMEN

Giardia duodenalis is a parasite that causes a large number of diarrheal diseases around the world. It is noteworthy that in a large number of processes, Giardia requires fewer components than other eukaryotes, even without some organelles such as mitochondria and peroxisomes. Despite this, core histones are known to exist in Giardia and epigenetic marks have been found on them, suggesting that they somehow control the expression of certain genes. The regulation of the expression of ribosomal DNA (rDNA) is essential, since it is required to maintain adequate levels of ribosomes and, given the nature of tandem repeat, it is a feasible area to create genomic instability. In Giardia, it is not known how this process occurs, but as in other eukaryotes, it is suggested through various epigenetic mechanisms. Thus, in the present work we seek to identify how chromatin is distributed through the Giardia rDNA and if there were histone marks that could control its expression.


Asunto(s)
Cromatina/metabolismo , ADN Protozoario/genética , ADN Ribosómico/genética , Epigénesis Genética , Giardia lamblia/genética , Animales , Histonas/genética , Histonas/metabolismo
15.
Acta Histochem ; 123(3): 151695, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33571696

RESUMEN

Sodium valproate (VPA) is a classic anticonvulsive, a histone deacetylase inhibitor, and a chromatin remodeling inducer. When injected into specimens of Triatoma infestans, a vector of Chagas disease, VPA affects the chromatin supraorganization of chromocenter heterochromatin in only a few cells of the Malpighian tubules. To test whether this result was explained by the inaccessibility of all of the organ's cells to the drug, we investigated the nuclear phenotypes and global acetylation of lysine 9 in histone H3 (H3K9ac) in Malpighian tubules cultivated in vitro for 1-24 h in the presence of 0.05 mM-1 mM VPA. The present results revealed that the chromatin decondensation event in the chromocenter body, which was detected only under low VPA concentrations up to a 4-h treatment, was not frequent during organ culture, similar to the results for injected insects. Cultivation of T. infestans Malpighian tubules in vitro for 24 h revealed inadequate for cell preservation even in the absence of the drug. Immunofluorescence signals for H3K9ac following VPA treatment showed a slightly increased intensity in the euchromatin, but were never detected in the chromocenter bodies, except with great intensity at their periphery, where the 18S rDNA is located. In conclusion, when VPA affects the chromocenter heterochromatin in this animal cell model, it occurs through a pathway that excludes a classic global H3K9ac mark. Investigation of nonhistone proteins associated with histone methylation marks is still required to further explain the differential response of T. infestans chromatin to VPA.


Asunto(s)
Eucromatina/metabolismo , Inhibidores de Histona Desacetilasas/farmacología , Triatoma/efectos de los fármacos , Ácido Valproico/farmacología , Acetilación/efectos de los fármacos , Animales , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Cromatina/efectos de los fármacos , Cromatina/metabolismo , Heterocromatina/metabolismo , Túbulos de Malpighi/citología , Túbulos de Malpighi/efectos de los fármacos , Triatoma/citología
16.
J Biophotonics ; 14(2): e202000274, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33025746

RESUMEN

Emerging evidence indicates the clinical benefits of photobiomodulation therapy (PBMT) in the management of skin and mucosal wounds. Here, we decided to explore the effects of different regiments of PBMT on epithelial cells and stem cells, and the potential implications over the epigenetic circuitry during healing. Scratch-wound migration, immunofluorescence (anti-acetyl-Histone H3, anti-acetyl-CBP/p300 and anti-BMI1), nuclear morphometry and western blotting (anti-Phospho-S6, anti-methyl-CpG binding domain protein 2 [MBD2]) were performed. Epithelial stem cells were identified by the aldehyde dehydrogenase enzymatic levels and sphere-forming assay. We observed that PBMT-induced accelerated epithelial migration and chromatin relaxation along with increased levels of histones acetylation, the transcription cofactors CBP/p300 and mammalian target of rapamycin. We further observed a reduction of the transcription repression-associated protein MBD2 and a reduced number of epithelial stem cells and spheres. In this study, we showed that PBMT could induce epigenetic modifications of epithelial cells and control stem cell fate, leading to an accelerated healing phenotype.


Asunto(s)
Terapia por Luz de Baja Intensidad , Acetilación , Epigénesis Genética , Código de Histonas , Células Madre , Cicatrización de Heridas
17.
Int J Parasitol ; 50(12): 1011-1022, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32822677

RESUMEN

Epigenetic mechanisms such as histone acetylation and deacetylation participate in regulation of the genes involved in encystation of Entamoeba invadens. However, the histones and target residues involved, and whether the acetylation and deacetylation of the histones leads to the regulation of gene expression associated with the encystation of this parasite, remain unknown. In this study, we found that E. invadens histone H4 is acetylated in both stages of the parasite and is more highly acetylated during the trophozoite stage than in the cyst. Histone hyperacetylation induced by Trichostatin A negatively affects the encystation of E. invadens, and this inhibition is associated with the downregulation of the expression of genes implicated in the synthesis of chitin, polyamines, gamma-aminobutyric acid pathways and cyst wall proteins, all of which are important in the formation of cysts. Finally, in silico analysis and activity assays suggest that a class I histone deacetylase (EiHDAC3) could be involved in control of the expression of a subset of genes that are important in several pathways during encystation. Therefore, the identification of enzymes that acetylate and/or deacetylate histones that control encystation in E. invadens could be a promising therapeutic target for preventing transmission of other amoebic parasites such as E. histolytica, the causative agent of amoebiasis in humans.


Asunto(s)
Entamoeba , Histona Desacetilasas/metabolismo , Animales , Quitina/metabolismo , Entamoeba/enzimología , Humanos , Procesamiento Proteico-Postraduccional , Trofozoítos/enzimología
18.
Eur J Pharmacol ; 882: 173268, 2020 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-32569675

RESUMEN

As SET protein is overexpressed and PP2A activity is reduced in oral squamous cell carcinoma (OSCC), this study aimed to assess the effects induced by OP449, a PP2A activator/SET inhibitor, on OSCC cells in vitro, and its potential either isolated or combined with FTY720, a PP2A activator/sphingosine kinase 1 antagonist, as antitumoral therapy in vivo. SET protein was analyzed in cells by immunoblotting and cancer stem cells by aldehyde dehydrogenase 1 assay (ALDH1). The cytotoxicity of OP449 was determined in five OSCC lineages by resazurin assay. Molecular actions of OP449 in SET targets were determined by immunoblotting. The coefficient of drug interaction (CDI) was used to characterize the synergism of OP449 and FTY720. The xenograft HN12 tumor model in nude mice was used to assess the antitumoral effect of OP449 and/or FTY720. HN12 (metastatic) cells showed higher SET and ALDH1 levels, and together with SCC9 cells were selected for molecular analysis. OP449 altered several SET functions/targets, such as histone H3 acetylation and NFkB. A synergism in cytotoxicity was observed when HN12 and SCC9 cells were pre-treated with 2 µM OP449 in combination with 15 µM FTY720 (CDI = 0.27 ± 0.088). Nude mice bearing xenograft HN12 tumors treated with OP449 and FTY720 showed reduced tumor mass. Moreover, NFkB was reduced in tumors after treatment. OP449 targets several SET functions, not only PP2A inhibition. Besides, OP449 plus FTY720 has a synergistic antitumoral effect on OSCC. Our results suggest new combined therapies and highlight SET and NFκB signaling as targets for OSCC therapy.


Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma de Células Escamosas/tratamiento farmacológico , Clorhidrato de Fingolimod/uso terapéutico , Neoplasias de la Boca/tratamiento farmacológico , Péptidos/uso terapéutico , Moduladores de los Receptores de fosfatos y esfingosina 1/uso terapéutico , Animales , Antineoplásicos/farmacología , Carcinoma de Células Escamosas/metabolismo , Línea Celular , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Proteínas de Unión al ADN/metabolismo , Sinergismo Farmacológico , Clorhidrato de Fingolimod/farmacología , Chaperonas de Histonas/metabolismo , Humanos , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias de la Boca/metabolismo , FN-kappa B/metabolismo , Péptidos/farmacología , Proteína Fosfatasa 2/metabolismo , Moduladores de los Receptores de fosfatos y esfingosina 1/farmacología
19.
Front Immunol ; 11: 756, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32425942

RESUMEN

Background: Epigenetic changes in response to allergen exposure are still not well understood. The aim of this study was to evaluate histone acetylation levels in peripheral blood leukocytes from humans naturally infected by intestinal parasites and perennially exposed to house dust mites (HDM). Methods: Peripheral blood mononuclear cells (PBMCs) were isolated by gradient centrifugation from 20 infected and 21 non-infected individuals living in a rural/village in Colombia. Histone 3 acetylation (H3Ac) and histone 4 acetylation (H4Ac) levels were measured in six immune genes previously associated with helminth immunity by chromatin immunoprecipitation (ChIP)-quantitative PCR. Then we analyzed the association between histone acetylation levels with total parasite egg burden and IgE levels. Results: We found an inverse correlation between H4Ac levels in the IL13 gene and egg worm burden that remained significant after adjustment by age [-0.20 (-0.32 to -0.09), p < 0.0001]. Moreover, we found significant associations between H4Ac levels in IL4 [0.32 (0.05-0.60), p = 0.02] and CHI3L1 [0.29 (0.08-0.51), p = 0.008] with the IgE levels to Ascaris lumbricoides. In addition, the levels of specific IgE antibodies to HDM were associated with H4Ac levels in the gene TNFSF13B encoding the B cell activating factor (BAFF) [0.51 (0.26-0.76), p < 0.001]. All values are presented as beta (95% CI). Conclusion: Histone acetylation levels at key type-2 immune genes in humans were modified by nematode infection and HDM allergens and are associated with the intensity of the IgE response.


Asunto(s)
Anticuerpos Antihelmínticos/inmunología , Antígenos Dermatofagoides/inmunología , Ascariasis/inmunología , Ascaris/inmunología , Factor Activador de Células B/genética , Proteína 1 Similar a Quitinasa-3/genética , Histonas/metabolismo , Inmunoglobulina E/inmunología , Interleucina-4/genética , Pyroglyphidae/inmunología , Acetilación , Adolescente , Adulto , Animales , Ascariasis/sangre , Ascariasis/epidemiología , Ascariasis/parasitología , Niño , Preescolar , Estudios de Cohortes , Colombia/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
20.
Addict Biol ; 25(2): e12737, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-30811820

RESUMEN

Dysregulation of histone deacetylases (HDAC) has been proposed as a potential contributor to aberrant transcriptional profiles that can lead to changes in cognitive functions. It is known that METH negatively impacts the prefrontal cortex (PFC) leading to cognitive decline and addiction whereas modafinil enhances cognition and has a low abuse liability. We investigated if modafinil (90 mg/kg) and methamphetmine (METH) (1 mg/kg) may differentially influence the acetylation status of histones 3 and 4 (H3ac and H4ac) at proximal promoters of class I, II, III, and IV HDACs. We found that METH produced broader acetylation effects in comparison with modafinil in the medial PFC. For single dose, METH affected H4ac by increasing its acetylation at class I Hdac1 and class IIb Hdac10, decreasing it at class IIa Hdac4 and Hdac5. Modafinil increased H3ac and decreased H4ac of Hdac7. For mRNA, single-dose METH increased Hdac4 and modafinil increased Hdac7 expression. For repeated treatments (4 d after daily injections over 7 d), we found specific effects only for METH. We found that METH increased H4ac in class IIa Hdac4 and Hdac5 and decreased H3/H4ac at class I Hdac1, Hdac2, and Hdac8. At the mRNA level, repeated METH increased Hdac4 and decreased Hdac2. Class III and IV HDACs were only responsive to repeated treatments, where METH affected the H3/H4ac status of Sirt2, Sirt3, Sirt7, and Hdac11. Our results suggest that HDAC targets linked to the effects of modafinil and METH may be related to the cognitive-enhancing vs cognitive-impairing effects of these psychostimulants.


Asunto(s)
Estimulantes del Sistema Nervioso Central/farmacología , Histona Desacetilasas/efectos de los fármacos , Metanfetamina/farmacología , Modafinilo/farmacología , Corteza Prefrontal/efectos de los fármacos , Acetilación/efectos de los fármacos , Animales , Modelos Animales de Enfermedad , Masculino , Ratones , Ratones Endogámicos C57BL , Corteza Prefrontal/fisiopatología
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