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1.
BMC Genomics ; 25(1): 788, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39148037

RESUMO

BACKGROUND: Somatic embryogenesis (SE) exemplifies the unique developmental plasticity of plant cells. The regulatory processes, including epigenetic modifications controlling embryogenic reprogramming of cell transcriptome, have just started to be revealed. RESULTS: To identify the genes of histone acetylation-regulated expression in SE, we analyzed global transcriptomes of Arabidopsis explants undergoing embryogenic induction in response to treatment with histone deacetylase inhibitor, trichostatin A (TSA). The TSA-induced and auxin (2,4-dichlorophenoxyacetic acid; 2,4-D)-induced transcriptomes were compared. RNA-seq results revealed the similarities of the TSA- and auxin-induced transcriptomic responses that involve extensive deregulation, mostly repression, of the majority of genes. Within the differentially expressed genes (DEGs), we identified the master regulators (transcription factors - TFs) of SE, genes involved in biosynthesis, signaling, and polar transport of auxin and NITRILASE-encoding genes of the function in indole-3-acetic acid (IAA) biosynthesis. TSA-upregulated TF genes of essential functions in auxin-induced SE, included LEC1/LEC2, FUS3, AGL15, MYB118, PHB, PHV, PLTs, and WUS/WOXs. The TSA-induced transcriptome revealed also extensive upregulation of stress-related genes, including those related to stress hormone biosynthesis. In line with transcriptomic data, TSA-induced explants accumulated salicylic acid (SA) and abscisic acid (ABA), suggesting the role of histone acetylation (Hac) in regulating stress hormone-related responses during SE induction. Since mostly the adaxial side of cotyledon explant contributes to SE induction, we also identified organ polarity-related genes responding to TSA treatment, including AIL7/PLT7, RGE1, LBD18, 40, HB32, CBF1, and ULT2. Analysis of the relevant mutants supported the role of polarity-related genes in SE induction. CONCLUSION: The study results provide a step forward in deciphering the epigenetic network controlling embryogenic transition in somatic cells of plants.


Assuntos
Arabidopsis , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Histonas , Ácidos Indolacéticos , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/efeitos dos fármacos , Ácidos Indolacéticos/metabolismo , Ácidos Indolacéticos/farmacologia , Acetilação , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Histonas/metabolismo , Técnicas de Embriogênese Somática de Plantas , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Transcriptoma , Ácidos Hidroxâmicos/farmacologia , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Inibidores de Histona Desacetilases/farmacologia
2.
FASEB J ; 38(16): e23884, 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39135512

RESUMO

The inhibition of the autophagolysosomal pathway mediated by transcription factor EB (TFEB) inactivation in proximal tubular epithelial cells (TECs) is a key mechanism of TEC injury in diabetic kidney disease (DKD). Acetylation is a novel mechanism that regulates TFEB activity. However, there are currently no studies on whether the adjustment of the acetylation level of TFEB can reduce the damage of diabetic TECs. In this study, we investigated the effect of Trichostatin A (TSA), a typical deacetylase inhibitor, on TFEB activity and damage to TECs in both in vivo and in vitro models of DKD. Here, we show that TSA treatment can alleviate the pathological damage of glomeruli and renal tubules and delay the DKD progression in db/db mice, which is associated with the increased expression of TFEB and its downstream genes. In vitro studies further confirmed that TSA treatment can upregulate the acetylation level of TFEB, promote its nuclear translocation, and activate the expression of its downstream genes, thereby reducing the apoptosis level of TECs. TFEB deletion or HDAC6 knockdown in TECs can counteract the activation effect of TSA on autophagolysosomal pathway. We also found that TFEB enhances the transcription of Tfeb through binding to its promoter and promotes its own expression. Our results, thus, provide a novel therapeutic mechanism for DKD that the alleviation of TEC damage by activating the autophagic lysosomal pathway through upregulating TFEB acetylation can, thus, delay DKD progression.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Nefropatias Diabéticas , Células Epiteliais , Inibidores de Histona Desacetilases , Ácidos Hidroxâmicos , Túbulos Renais Proximais , Animais , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Nefropatias Diabéticas/metabolismo , Camundongos , Acetilação , Células Epiteliais/metabolismo , Células Epiteliais/efeitos dos fármacos , Túbulos Renais Proximais/metabolismo , Túbulos Renais Proximais/patologia , Ácidos Hidroxâmicos/farmacologia , Inibidores de Histona Desacetilases/farmacologia , Masculino , Camundongos Endogâmicos C57BL , Autofagia/efeitos dos fármacos , Apoptose/efeitos dos fármacos
3.
Exp Cell Res ; 440(1): 114126, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38857838

RESUMO

Microtubules are components of the cytoskeleton that perform essential functions in eukaryotes, such as those related to shape change, motility and cell division. In this context some characteristics of these filaments are essential, such as polarity and dynamic instability. In trypanosomatids, microtubules are integral to ultrastructure organization, intracellular transport and mitotic processes. Some species of trypanosomatids co-evolve with a symbiotic bacterium in a mutualistic association that is marked by extensive metabolic exchanges and a coordinated division of the symbiont with other cellular structures, such as the nucleus and the kinetoplast. It is already established that the bacterium division is microtubule-dependent, so in this work, it was investigated whether the dynamism and remodeling of these filaments is capable of affecting the prokaryote division. To this purpose, Angomonas deanei was treated with Trichostatin A (TSA), a deacetylase inhibitor, and mutant cells for histone deacetylase 6 (HDAC6) were obtained by CRISPR-Cas9. A decrease in proliferation, an enhancement in tubulin acetylation, as well as morphological and ultrastructural changes, were observed in TSA-treated protozoa and mutant cells. In both cases, symbiont filamentation occurred, indicating that prokaryote cell division is dependent on microtubule dynamism.


Assuntos
Divisão Celular , Microtúbulos , Simbiose , Microtúbulos/metabolismo , Microtúbulos/ultraestrutura , Microtúbulos/efeitos dos fármacos , Trypanosomatina/genética , Trypanosomatina/metabolismo , Trypanosomatina/ultraestrutura , Trypanosomatina/fisiologia , Ácidos Hidroxâmicos/farmacologia , Tubulina (Proteína)/metabolismo , Tubulina (Proteína)/genética , Bactérias/metabolismo , Bactérias/genética , Acetilação , Inibidores de Histona Desacetilases/farmacologia , Desacetilase 6 de Histona/metabolismo , Desacetilase 6 de Histona/genética , Citoesqueleto/metabolismo , Citoesqueleto/ultraestrutura
4.
Molecules ; 29(11)2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38893499

RESUMO

Trichostatin A (TSA), a histone deacetylase (HDAC) inhibitor, promotes the cytotoxicity of the genotoxic anticancer drug cisplatin, yet the underlying mechanism remains poorly understood. Herein, we revealed that TSA at a low concentration (1 µM) promoted the cisplatin-induced activation of caspase-3/6, which, in turn, increased the level of cleaved PARP1 and degraded lamin A&C, leading to more cisplatin-induced apoptosis and G2/M phase arrest of A549 cancer cells. Both ICP-MS and ToF-SIMS measurements demonstrated a significant increase in DNA-bound platinum in A549 cells in the presence of TSA, which was attributable to TSA-induced increase in the accessibility of genomic DNA to cisplatin attacking. The global quantitative proteomics results further showed that in the presence of TSA, cisplatin activated INF signaling to upregulate STAT1 and SAMHD1 to increase cisplatin sensitivity and downregulated ICAM1 and CD44 to reduce cell migration, synergistically promoting cisplatin cytotoxicity. Furthermore, in the presence of TSA, cisplatin downregulated TFAM and SLC3A2 to enhance cisplatin-induced ferroptosis, also contributing to the promotion of cisplatin cytotoxicity. Importantly, our posttranslational modification data indicated that acetylation at H4K8 played a dominant role in promoting cisplatin cytotoxicity. These findings provide novel insights into better understanding the principle of combining chemotherapy of genotoxic drugs and HDAC inhibitors for the treatment of cancers.


Assuntos
Antineoplásicos , Apoptose , Cisplatino , Ácidos Hidroxâmicos , Cisplatino/farmacologia , Humanos , Apoptose/efeitos dos fármacos , Ácidos Hidroxâmicos/farmacologia , Antineoplásicos/farmacologia , Células A549 , Inibidores de Histona Desacetilases/farmacologia , Linhagem Celular Tumoral , Acetilação/efeitos dos fármacos , Sinergismo Farmacológico
5.
Stem Cell Reports ; 19(6): 906-921, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38729154

RESUMO

Removal of somatic histone H3 lysine 9 trimethylation (H3K9me3) from the embryonic genome can improve the efficiency of mammalian cloning using somatic cell nuclear transfer (SCNT). However, this strategy involves the injection of histone demethylase mRNA into embryos, which is limiting because of its invasive and labor-consuming nature. Here, we report that treatment with an inhibitor of G9a (G9ai), the major histone methyltransferase that introduces H3K9me1/2 in mammals, greatly improved the development of mouse SCNT embryos. Intriguingly, G9ai caused an immediate reduction of H3K9me1/2, a secondary loss of H3K9me3 in SCNT embryos, and increased the birth rate of cloned pups about 5-fold (up to 3.9%). G9ai combined with the histone deacetylase inhibitor trichostatin A further improved this rate to 14.5%. Mechanistically, G9ai and TSA synergistically enhanced H3K9me3 demethylation and boosted zygotic genome activation. Thus, we established an easy, highly effective SCNT protocol that would enhance future cloning research and applications.


Assuntos
Histona-Lisina N-Metiltransferase , Histonas , Técnicas de Transferência Nuclear , Animais , Histonas/metabolismo , Camundongos , Histona-Lisina N-Metiltransferase/metabolismo , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/antagonistas & inibidores , Metilação , Clonagem de Organismos/métodos , Embrião de Mamíferos/metabolismo , Desenvolvimento Embrionário/efeitos dos fármacos , Desenvolvimento Embrionário/genética , Ácidos Hidroxâmicos/farmacologia , Feminino , Inibidores de Histona Desacetilases/farmacologia
6.
Front Pharmacol ; 15: 1333235, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38572429

RESUMO

Background: Cognitive deficits and behavioral disorders such as anxiety and depression are common manifestations of Alzheimer's disease (AD). Our previous work demonstrated that Trichostatin A (TSA) could alleviate neuroinflammatory plaques and improve cognitive disorders. AD, anxiety, and depression are all associated with microglial inflammation. However, whether TSA could attenuate anxiety- and depression-like behaviors in APP/PS1 mice through anti-inflammatory signaling is still unclearly. Methods: In the present study, all mice were subjected to the open field, elevated plus maze, and forced swim tests to assess anxiety- and depression-related behaviors after TSA administration. To understand the possible mechanisms underlying the behavioral effects observed, CST7 was measured in the hippocampus of mice and LPS-treated BV2 microglia. Results: The results of this study indicated that TSA administration relieved the behaviors of depression and anxiety in APP/PS1 mice, and decreased CST7 levels in the hippocampus of APP/PS1 mice and LPS-induced BV2 cells. Conclusion: Overall, these findings support the idea that TSA might be beneficial for reducing neurobehavioral disorders in AD and this could be due to suppression of CST7-related microglial inflammation.

7.
Braz. j. med. biol. res ; 57: e12874, fev.2024. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1557324

RESUMO

More attention has been paid to immunotherapy for ovarian cancer and the development of tumor vaccines. We developed a trichostatin A (TSA)-modified tumor vaccine with potent immunomodulating activities that can inhibit the growth of ovarian cancer in rats and stimulate immune cell response in vivo. TSA-treated Nutu-19 cells inactivated by X-ray radiation were used as a tumor vaccine in rat ovarian cancer models. Prophylactic and therapeutic experiments were performed with TSA-modified tumor vaccine in rats. Flow cytometry and ELISpot assays were conducted to assess immune response. Immune cell expression in the spleen and thymus were detected by immunohistochemical staining. GM-CSF, IL-7, IL-17, LIF, LIX, KC, MCP-1, MIP-2, M-CSF, IP-10/CXCL10, MIG/CXCL9, RANTES, IL-4, IFN-γ, and VEGF expressions were detected with Milliplex Map Magnetic Bead Panel immunoassay. TSA vaccination in therapeutic and prophylactic models could effectively stimulate innate immunity and boost the adaptive humoral and cell-mediated immune responses to inhibit the growth and tumorigenesis of ovarian cancer. This vaccine stimulated the thymus into reactivating status and enhanced infiltrating lymphocytes in tumor-bearing rats. The expression of key immunoregulatory factors were upregulated in the vaccine group. The intensities of infiltrating CD4+ and CD8+ T cells and NK cells were significantly increased in the vaccine group compared to the control group (P<0.05). This protection was mainly dependent on the IFN-γ pathway and, to a much lesser extent, by the IL-4 pathway. The tumor cells only irradiated by X-ray as the control group still showed a slight immune effect, indicating that irradiated cells may also cause certain immune antigen exposure, but the efficacy was not as significant as that of the TSA-modified tumor vaccine. Our study revealed the potential application of the TSA-modified tumor vaccine as a novel tumor vaccine against tumor refractoriness and growth. These findings offer a better understanding of the immunomodulatory effects of the vaccine against latent tumorigenesis and progression. This tumor vaccine therapy may increase antigen exposure, synergistically activate the immune system, and ultimately improve remission rates. A vaccine strategy designed to induce effective tumor immune response is being considered for cancer immunotherapy.

8.
Asian Pac J Cancer Prev ; 24(12): 4085-4092, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38156841

RESUMO

OBJECTIVE: The aim of study was to investigate the correlation of GLUT3 upregulation and butyrate-mediated acquired chemoresistance. METHOD: A butyrate-resistant CRC cell model was established from parental (PT) HCT116 cells by gradually increasing the concentration of sodium butyrate (NaBu), followed by evaluation of resistance to butyrate and trichostatin A (TSA) by the MTT method. The expression of SLC2A3 gene and GLUT3 protein were assessed by semi-quantitative RT-PCR and western blotting, respectively. The correlation of GLUT3 and butyrate-induced acquired chemoresistance was investigated using SLC2A3 silencing. RESULTS: Butyrate-resistant (BR) HCT116 cells were more tolerant to butyrate-induced cell death and also resist to 750 and 1000 nM TSA when compared with HCT116-PT cells (p <0.05). Long-term exposure to butyrate revealed that upregulation of the SLC2A3 gene was significantly increased by more than 20 fold (p < 0.01), and that of GLUT3 was elevated by approximately 2 fold (p < 0.05) in HCT116-BR cells. Silencing of the SLC2A3 gene increased the sensitivity of HCT116-BR cells to the effects of TSA. CONCLUSION: Upregulation of GLUT3 is associated with resistance to butyrate and TSA. GLUT3 is a molecular target for the detection of chemoresistant CRC cells and thus a potential target for diagnostic strategies.


Assuntos
Neoplasias Colorretais , Humanos , Células HCT116 , Transportador de Glucose Tipo 3 , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Ácido Butírico/farmacologia
9.
Plants (Basel) ; 12(24)2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38140504

RESUMO

The ability for plant regeneration from dedifferentiated cells opens up the possibility for molecular bioengineering to produce crops with desirable traits. Developmental and environmental signals that control cell totipotency are regulated by gene expression via dynamic chromatin remodeling. Using a mass spectrometry-based approach, we investigated epigenetic changes to the histone proteins during callus formation from roots and shoots of Arabidopsis thaliana seedlings. Increased levels of the histone H3.3 variant were found to be the major and most prominent feature of 20-day calli, associated with chromatin relaxation. The methylation status in root- and shoot-derived calli reached the same level during long-term propagation, whereas differences in acetylation levels provided a long-lasting imprint of root and shoot origin. On the other hand, epigenetic signs of origin completely disappeared during 20 days of calli propagation in the presence of histone deacetylase inhibitors (HDACi), sodium butyrate, and trichostatin A. Each HDACi affected the state of post-translational histone modifications in a specific manner; NaB-treated calli were epigenetically more similar to root-derived calli, and TSA-treated calli resembled shoot-derived calli.

10.
Rev. argent. microbiol ; 55(4): 4-4, Dec. 2023.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1550711

RESUMO

Abstract Chromatin remodeling enzymes are important "writers'', "readers'' and "erasers'' of the epigenetic code. These proteins are responsible for the placement, recognition, and removal of molecular marks in histone tails that trigger structural and functional changes in chromatin. This is also the case for histone deacetylases (HDACs), i.e., enzymes that remove acetyl groups from histone tails, signaling heterochromatin formation. Chromatin remodeling is necessary for cell differentiation processes in eukaryotes, and fungal pathogenesis in plants includes many adaptations to cause disease. Macrophomina phaseolina (Tassi) Goid. is a nonspe-cific, necrotrophic ascomycete phytopathogen that causes charcoal root disease. M. phaseolina is a frequent and highly destructive pathogen in crops such as common beans (Phaseolus vulgaris L.), particularly under both water and high temperature stresses. Here, we evaluated the effects of the classical HDAC inhibitor trichostatin A (TSA) on M. phaseolina in vitro growth and virulence. During inhibition assays, the growth of M. phaseolina in solid media, as well as the size of the microsclerotia, were reduced (p <0.05), and the colony morphology was remark-ably affected. Under greenhouse experiments, treatment with TSA reduced (p <0.05) fungal virulence in common bean cv. BAT 477. Tests of LIPK, MAC1 and PMK1 gene expression during the interaction of fungi with BAT 477 revealed noticeable deregulation. Our results provide additional evidence about the role of HATs and HDACs in important biological processes of M. phaseolina.


Resumen Las enzimas remodeladoras de la cromatina son «escritores¼, «lectores¼ y «borradores¼ importantes del código epigenético. Estas proteínas son responsables de la localización, el reconocimiento y la remoción de las marcas moleculares sobre las terminaciones de las histonas que desencadenan cambios funcionales y estructurales en la cromatina. Es el caso de las desacetilasas de histonas (HDAC), enzimas que remueven grupos acetilo de las «colas¼ de las histonas, señalizando la formación de heterocromatina. La anterior es una actividad necesaria en los procesos de diferenciación celular de los eucariotas, y se conoce que la patogénesis fúngica en las plantas requiere de adaptaciones diversas para ocasionar enfermedad. Macrophomina phaseolina (Tassi) Goid. es un ascomiceto fitopatógeno, necrótrofo e inespecífico, causante de la pudrición carbonosa. Este es un hongo frecuente y altamente destructivo en cultivos como fríjol común (Phaseolus vulgaris L.), particularmente bajo estrés hídrico y térmico. En este trabajo evaluamos los efectos del inhibidor de HDAC clásicas tricostatina A (TSA) sobre el crecimiento in vitro y la virulencia de M. phaseolina. El TSA redujo el crecimiento de M. phaseolina en medio sólido y el tamano de los microesclerocios (p < 0,05), lo que afectó la morfología colonial. En invernadero, el tratamiento con TSA disminuyó (p<0,05) la gravedad de la infección en la variedad de frijol BAT 477. La expresión de los genes de patogenicidad LIPK, MAC1 y PMK1 durante la interacción del hongo con la planta reveló una desregulación importante. Estos resultados proporcionan evidencia adicional del papel que cumplen las HDAC en la regulación de procesos biológicos fundamentales de M. phaseolina. © 2023 Asociación Argentina de Microbiología. Publicado por Elsevier Espana, S.L.U.

11.
Braz. J. Pharm. Sci. (Online) ; 57: e19033, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1345461

RESUMO

Previously, we evaluated the effect of trichostatin A (TSA) on the expression of DNA methyltransferase 1 (DNMT1) in Hepatocellular Carcinoma (HCC). Fragile histidine triad (FHIT) and WW domain-containing oxidoreductase (WWOX) are two of the most common down-regulated genes in many cancers located on chromosome 3p14.2 and 16q23.3-24.1 respectively. The aim of the current study was to assess the effect of TSA on these genes expression, cell growth, and apoptosis in HCC WCH 17 cell. The cells were seeded and treated with TSA at different times. Then, MTT assay, flow cytometry, and qRT-PCR were achieved to determine viability, apoptosis and gene expression respectively. Cell growth was significantly inhibited, 92 to 36% after 24 h, 86 to 28% after 48 h, and 78 to 24% after 72 h. The results of flow cytometry confirmed that TSA increased apoptosis compared to the control group, the apoptosis percentage increased to 12%, 16%, and 18% in comparison to control groups (2%). Significant up-regulation of the genes was observed in all treated groups. We concluded that re-expression of silenced WWOX and FHIT genes could be achieved by TSA resulting in cell growth inhibition and apoptosis induction in WCH 17 cell.


Assuntos
Apoptose/fisiologia , Carcinoma Hepatocelular/patologia , Oxidorredutase com Domínios WW , Crescimento/fisiologia , Cromossomos/classificação , Citometria de Fluxo/instrumentação , Neoplasias/classificação
12.
Parasitology, v. 146, n. 4, p. 543-552, abr. 2019
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-2708

RESUMO

Trypanosoma cruzi, the causative agent of Chagas disease, is a public health concern in Latin America. Epigenetic events, such as histone acetylation, affect DNA topology, replication and gene expression. Histone deacetylases (HDACs) are involved in chromatin compaction and post-translational modifications of cytoplasmic proteins, such as tubulin. HDAC inhibitors, like trichostatin A (TSA), inhibit tumour cell proliferation and promotes ultrastructural modifications. In the present study, TSA effects on cell proliferation, viability, cell cycle and ultrastructure were evaluated, as well as on histone acetylation and tubulin expression of the T. cruzi epimastigote form. Protozoa proliferation and viability were reduced after treatment with TSA. Quantitative proteomic analyses revealed an increase in histone acetylation after 72 h of TSA treatment. Surprisingly, results obtained by different microscopy methodologies indicate that TSA does not affect chromatin compaction, but alters microtubule cytoskeleton dynamics and impair kDNA segregation, generating polynucleated cells with atypical morphology. Confocal fluorescence microscopy and flow cytometry assays indicated that treated cell microtubules were more intensely acetylated. Increases in tubulin acetylation may be directly related to the higher number of parasites in the G2/M phase after TSA treatment. Taken together, these results suggest that deacetylase inhibitors represent excellent tools for understanding trypanosomatid cell biology.

13.
Braz. j. med. biol. res ; 46(5): 405-416, maio 2013. graf
Artigo em Inglês | LILACS | ID: lil-675676

RESUMO

Epigenetic mechanisms such as DNA methylation and histone modification are important in stem cell differentiation. Methylation is principally associated with transcriptional repression, and histone acetylation is correlated with an active chromatin state. We determined the effects of these epigenetic mechanisms on adipocyte differentiation in mesenchymal stem cells (MSCs) derived from bone marrow (BM-MSCs) and adipose tissue (ADSCs) using the chromatin-modifying agents trichostatin A (TSA), a histone deacetylase inhibitor, and 5-aza-2′-deoxycytidine (5azadC), a demethylating agent. Subconfluent MSC cultures were treated with 5, 50, or 500 nM TSA or with 1, 10, or 100 µM 5azadC for 2 days before the initiation of adipogenesis. The differentiation was quantified and expression of the adipocyte genes PPARG and FABP4 and of the anti-adipocyte gene GATA2 was evaluated. TSA decreased adipogenesis, except in BM-MSCs treated with 5 nM TSA. Only treatment with 500 nM TSA decreased cell proliferation. 5azadC treatment decreased proliferation and adipocyte differentiation in all conditions evaluated, resulting in the downregulation of PPARG and FABP4 and the upregulation of GATA2. The response to treatment was stronger in ADSCs than in BM-MSCs, suggesting that epigenetic memories may differ between cells of different origins. As epigenetic signatures affect differentiation, it should be possible to direct the use of MSCs in cell therapies to improve process efficiency by considering the various sources available.


Assuntos
Adulto , Humanos , Pessoa de Meia-Idade , Adipócitos/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Desoxicitidina/farmacologia , Inibidores de Histona Desacetilases/farmacologia , Ácidos Hidroxâmicos/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Adipócitos/citologia , Western Blotting , Células Cultivadas , Proliferação de Células/efeitos dos fármacos , Metilação de DNA , Epigenômica , Imunofluorescência , Reação em Cadeia da Polimerase/métodos , Regulação para Cima
14.
Acta méd. colomb ; 37(3): 117-126, jul.-set. 2012. tab
Artigo em Espanhol | LILACS | ID: lil-656812

RESUMO

Objetivo: la obesidad ha aumentado en todo el mundo, no obstante existen pocas opciones terapéuticas novedosas y la inclinación a actividades cruentas para la terapia de obesidad y diabetes mellitus 2 no dejan de ser un riesgo. Con el fin de valorar el efecto de compuestos sobre la actividad de la célula grasa, estudiamos en forma preclínica la actividad de ácido valproico, tricostatin a (inhibidor de histonas deacetilasas) y EID1 (inhibidor de EP300), el cual reduce la actividad de PPARg en un modelo de células preadipocíticas 3T3-l1. Métodos: se realizó transfecciones transitorias con lipofectamina a las células 3T3-l1 y 293. las células unipotentes 3T3-L1 fueron sometidas a diferenciación con el coctel específico para diferenciación y se les adicionaron los compuestos a concentraciones fisiológicas para las células. Se valoró la expresión de UCP1 mediante Western blot y los experimentos se realizaron por triplicado. Resultados: se observó que el efecto de tricostatin a fue mayor que el del ácido valproico en actividad lipolítica, no obstante ambos compuestos ejercen una efecto aditivo sobre la actividad de EID1 en la diferenciación de la célula adiposa. EID1 es capaz de estimular la actividad de proteína UCP1, cuya expresión es propia del adipocito marrón. Conclusiones: EID1 es una proteína que puede ser referente para inducir una célula adiposa calorigénica más activa, reduciendo la acumulación de lípidos en célula grasa. el efecto de ácido valproico y tricostatin a pueden servir de parámetro para la búsqueda de nuevos planes terapéuticos dirigidos a la obesidad. (Acta Med Colomb 2012; 37: 125-130).


Objective: obesity has increased worldwide, but there are currently few novel therapeutic options and the tendency to invasive procedures for the therapy of obesity and diabetes mellitus 2 are still an important risk. in order to assess the effect of compounds on the fat cell activity, we studied preclinically the activity of valproic acid, tricostatin a (histone deacetylase inhibitor) and EID1 (EP300 inhibitor) which reduces the activity of PPARg, in a model of preadipocyte 3T3-l1 cells. Methods: transient transfections were performed with lipofectamine in 3T3-l1 and 293 cells. Unipotent 3T3-L1 cells underwent differentiation with the specific cocktail and the compounds were added to cells in physiological concentrations. We assessed the UCP1 expression through western blot, and the experiments were performed in triplicate. Results: we observed that the effect of tricostatin a was higher than that of the valproic acid in regard to lipolytic activity; however, both compounds exert an additive effect on EID1 activity in adipose cell differentiation. EID1 is able to stimulate the activity of protein UCP1, whose expression is characteristic of brown adipocyte. Conclusions: EID1 is a reference protein to induce in the adipose cell higher caloric activity, reducing the accumulation of lipids in the adipocyte. The effect of valproic acid and tricostatin a can serve as a parameter for the search of new targeted therapeutic plans for obesity. (Acta Med Colomb2012; 37: 125-130).

15.
Genet. mol. biol ; 34(1): 19-24, 2011. ilus
Artigo em Inglês | LILACS | ID: lil-573707

RESUMO

A potential strategy to combat obesity and its associated complications involves modifying gene expression in adipose cells to reduce lipid accumulation. The nuclear receptor Peroxisome Proliferator-activated receptor gamma (PPARγ) is the master regulator of adipose cell differentiation and its functional activation is currently used as a therapeutic approach for Diabetes Mellitus type 2. However, total activation of PPARγ induces undesirable secondary effects that might be set with a partial activation. A group of proteins that produce histone demethylation has been shown to modify the transcriptional activity of nuclear receptors. Here we describe the repressive action of the jumonji domain containing 2C/lysine demethylase 4 C (JMJD2C/KDM4C) on PPARγ transcriptional activation. JMJD2C significantly reduced the rosiglitazone stimulated PPARγ activation. This effect was mainly observed in experiments performed using the Tudor domains that may interact with histone deacetylase class 1 (HDAC) and this interaction probably reduces the mediated activation of PPARγ. Trichostatin A, a HDAC inhibitor, reduces the repressive effect of JMJD2C. When JMJD2C was over-expressed in 3T3-L1 cells, a reduction of differentiation was observed with the Tudor domain. In summary, we herein describe JMJD2C-mediated reduction of PPARgamma transcriptional activation as well as preadipocyte differentiation. This novel action of JMJD2C might have an important role in new therapeutic approaches to treat obesity and its complications.


Assuntos
Humanos , Adipócitos , Histona Desacetilases , Histonas , Receptores Ativados por Proliferador de Peroxissomo
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