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1.
Hum Genet ; 143(1): 1-17, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37999799

RESUMO

Diabetes mellitus (DM) has become a significant health concern with an increasing rate of morbidity and mortality worldwide. India ranks second in the number of diabetes cases in the world. The increasing burden of DM can be explained by genetic predisposition of Indians to type 2 diabetes mellitus (T2DM) coupled with rapid urbanization and socio-economic development in the last 3 decades leading to drastic changes in lifestyle. Environment and lifestyle changes contribute to T2DM development by altering epigenetic processes such as DNA methylation, histone post-translational modifications, and long non-coding RNAs, all of which regulate chromatin structure and gene expression. Although the genetic predisposition of Indians to T2DM is well established, how environmental and genetic factors interact and lead to T2DM is not well understood. In this review, we discuss the prevalence of diabetes and its complications across different states in India and how various risk factors contribute to its pathogenesis. The review also highlights the role of genetic predisposition among the Indian population and epigenetic factors involved in the etiology of diabetes. Lastly, we review current treatments and emphasize the knowledge gap with respect to genetic and epigenetic factors in the Indian context. Further understanding of the genetic and epigenetic determinants will help in risk prediction and prevention as well as therapeutic interventions, which will improve the clinical management of diabetes and associated macro- and micro-vascular complications.


Assuntos
Complicações do Diabetes , Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/epidemiologia , Epigênese Genética , Metilação de DNA , Histonas/genética , Predisposição Genética para Doença , Índia/epidemiologia , Complicações do Diabetes/complicações , Complicações do Diabetes/epidemiologia , Complicações do Diabetes/genética
2.
J Biochem ; 175(2): 205-213, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-37963603

RESUMO

TFIIIC is a multi-subunit complex required for tRNA transcription by RNA polymerase III. Human TFIIIC holo-complex possesses lysine acetyltransferase activity that aids in relieving chromatin-mediated repression for RNA polymerase III-mediated transcription and chromatin assembly. Here we have characterized the acetyltransferase activity of the largest and DNA-binding subunit of TFIIIC complex, TFIIIC220. Purified recombinant human TFIIIC220 acetylated core histones H3, H4 and H2A in vitro. Moreover, we have identified the putative catalytic domain of TFIIIC220 that efficiently acetylates core histones in vitro. Mutating critical residues of the putative acetyl-CoA binding 'P loop' drastically reduced the catalytic activity of the acetyltransferase domain. Further analysis showed that the knockdown of TFIIIC220 in mammalian cell lines dramatically reduces global H3K18 acetylation level, which was rescued by overexpression of the putative acetyltransferase domain of human TFIIIC220. Our findings indicated a possibility of a crucial role for TFIIIC220 in maintaining acetylation homeostasis in the cell.


Assuntos
Histonas , Lisina Acetiltransferases , Fatores de Transcrição TFIII , Animais , Humanos , Histonas/metabolismo , Lisina Acetiltransferases/metabolismo , RNA Polimerase III/metabolismo , Histona Acetiltransferases/genética , Histona Acetiltransferases/metabolismo , Acetilação , Mamíferos
3.
Inj Prev ; 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38050086

RESUMO

INTRODUCTION: Road traffic injuries (RTIs), particularly motorbike injuries, are one of the leading causes of death worldwide and have been a serious concern in low- and middle-income countries like Bangladesh. Therefore, this study aimed to assess the level of knowledge and practices on road safety measures among motorbikers in Dhaka, Bangladesh. METHODS: This cross-sectional study was conducted from January 2022 to December 2022 among 350 motorbikers of Dhaka city via a series of face-to-face interviews. Motorbikers who regularly ride a motorcycle were interviewed about their road safety knowledge and practices through a two-stage cluster sampling technique. Frequency distribution, independent sample t-test and one-way analysis of variance (ANOVA) were performed in data analysis. RESULTS: Out of the 350 motorbikers, only 54.6% had good knowledge and 16.9% had poor knowledge on the signs and safety regulations of roads. Moreover, only 50.6% of respondents followed good practices while 23.4% followed poor practices of road safety measures. One-way ANOVA analysis demonstrates that the average knowledge score was significantly (p<0.05) higher among higher-educated, unmarried and non-smokers. Additionally, higher education level, non-smoking status and being Muslim were significantly (p<0.05) associated with good road safety practices. CONCLUSIONS: The overall good knowledge level and practices of road safety measures among the motorbikers was not satisfactory although the majority of them knew individual signs and regulations. Therefore, this study suggests that education and strict enforcement of traffic rules may increase their knowledge and practice behaviour regarding road safety which in turn would minimise traffic injuries and fatalities.

4.
Front Mol Biosci ; 10: 1204124, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37325470

RESUMO

Background: MicroRNAs (miRNAs) and long non-coding RNAs (lncRNAs) play key roles in diabetic kidney disease (DKD). The miR-379 megacluster of miRNAs and its host transcript lnc-megacluster (lncMGC) are regulated by transforming growth factor-ß (TGF-ß), increased in the glomeruli of diabetic mice, and promote features of early DKD. However, biochemical functions of lncMGC are unknown. Here, we identified lncMGC-interacting proteins by in vitro-transcribed lncMGC RNA pull down followed by mass spectrometry. We also created lncMGC-knockout (KO) mice by CRISPR-Cas9 editing and used primary mouse mesangial cells (MMCs) from the KO mice to examine the effects of lncMGC on the gene expression related to DKD, changes in promoter histone modifications, and chromatin remodeling. Methods: In vitro-transcribed lncMGC RNA was mixed with lysates from HK2 cells (human kidney cell line). lncMGC-interacting proteins were identified by mass spectrometry. Candidate proteins were confirmed by RNA immunoprecipitation followed by qPCR. Cas9 and guide RNAs were injected into mouse eggs to create lncMGC-KO mice. Wild-type (WT) and lncMGC-KO MMCs were treated with TGF-ß, and RNA expression (by RNA-seq and qPCR) and histone modifications (by chromatin immunoprecipitation) and chromatin remodeling/open chromatin (by Assay for Transposase-Accessible Chromatin using sequencing, ATAC-seq) were examined. Results: Several nucleosome remodeling factors including SMARCA5 and SMARCC2 were identified as lncMGC-interacting proteins by mass spectrometry, and confirmed by RNA immunoprecipitation-qPCR. MMCs from lncMGC-KO mice showed no basal or TGF-ß-induced expression of lncMGC. Enrichment of histone H3K27 acetylation and SMARCA5 at the lncMGC promoter was increased in TGF-ß-treated WT MMCs but significantly reduced in lncMGC-KO MMCs. ATAC peaks at the lncMGC promoter region and many other DKD-related loci including Col4a3 and Col4a4 were significantly lower in lncMGC-KO MMCs compared to WT MMCs in the TGF-ß-treated condition. Zinc finger (ZF), ARID, and SMAD motifs were enriched in ATAC peaks. ZF and ARID sites were also found in the lncMGC gene. Conclusion: lncMGC RNA interacts with several nucleosome remodeling factors to promote chromatin relaxation and enhance the expression of lncMGC itself and other genes including pro-fibrotic genes. The lncMGC/nucleosome remodeler complex promotes site-specific chromatin accessibility to enhance DKD-related genes in target kidney cells.

5.
Arterioscler Thromb Vasc Biol ; 43(7): 1157-1175, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37128912

RESUMO

BACKGROUND: Obesity and diabetes are associated with elevated free fatty acids like palmitic acid (PA), which promote chronic inflammation and impaired inflammation resolution associated with cardiometabolic disorders. Long noncoding RNAs (lncRNAs) are implicated in inflammatory processes; however, their roles in PA-regulated inflammation and resolution are unclear. METHODS: We performed RNA-sequencing analysis to identify PA-regulated coding genes and novel lncRNAs in CD14+ monocytes from healthy volunteers. We investigated the regulation and function of an uncharacterized PA-induced lncRNA PARAIL (PA-regulated anti-inflammatory lncRNA). We examined its role in inflammation resolution by employing knockdown and overexpression strategies in human and mouse macrophages. We also used RNA pulldown coupled with mass spectrometry to identify PARAIL interacting nuclear proteins and their mechanistic involvement in PARAIL functions in human macrophages. RESULTS: Treatment of human CD14+ monocytes with PA-induced several lncRNAs and genes associated with inflammatory phenotype. PA strongly induced lncRNA PARAIL expressed near RIPK2. PARAIL was also induced by cytokines and infectious agents in human monocytes/macrophages and was regulated by NF-κB (nuclear factor-kappa B). Time course studies showed PARAIL was induced during inflammation resolution phase in PA-treated macrophages. PARAIL knockdown with antisense oligonucleotides upregulated key inflammatory genes and vice versa with PARAIL overexpression. We found that PARAIL interacts with ELAVL1 (ELAV-like RNA-binding protein 1) protein via adenylate/uridylate-rich elements (AU-rich elements; AREs). ELAVL1 knockdown inhibited the anti-inflammatory functions of PARAIL. Moreover, PARAIL knockdown increased cytosolic localization of ELAVL1 and increased the stability of ARE-containing inflammatory genes. Mouse orthologous Parail was downregulated in macrophages from mice with diabetes and atherosclerosis. Parail overexpression attenuated proinflammatory genes in mouse macrophages. CONCLUSIONS: Upregulation of PARAIL under acute inflammatory conditions contributes to proresolution mechanisms via PARAIL-ELAVL1 interactions. Conversely, PARAIL downregulation in cardiometabolic diseases enhances ELAVL1 function and impairs inflammation resolution to further augment inflammation. Thus, inflammation-resolving lncRNAs like PARAIL represent novel targets to combat inflammatory cardiometabolic diseases.


Assuntos
Aterosclerose , RNA Longo não Codificante , Humanos , Camundongos , Animais , Monócitos/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Ácido Palmítico/toxicidade , Ácido Palmítico/metabolismo , Macrófagos/metabolismo , Inflamação/induzido quimicamente , Inflamação/genética , Inflamação/metabolismo , NF-kappa B/metabolismo , Aterosclerose/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Proteína Semelhante a ELAV 1/genética , Proteína Semelhante a ELAV 1/metabolismo
6.
Appl Phys A Mater Sci Process ; 128(10): 866, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36101661

RESUMO

In this work, a shock-free argon-fed plasma plume was generated by a variable-frequency power supply and the discharge characteristics were investigated from the voltage and current waveforms between 72 and 92 kHz frequencies. The higher electron temperature dominates the plasma chemical process and the average plasma temperature is about 30 â„ƒ under these conditions. The influence of non-thermal atmospheric plasma plume length and plume temperature on Ar gas flow is optimized at 7 sL/min. The average charge accumulation on the plume tip area and the dependence of flow rate on the plasma irradiation area were also explored. This atmospheric pressure plasma jet (APPJ) has been proposed for human-skin irradiation on different areas (even on the tongue) owing to its less painful, tingling and burning effect. Optical emission spectroscopy (OES) confirmed the presence of excited argon with reactive nitrogen (RNS) and oxygen species (ROS). This study contributes to a better understanding of non-thermal plasma effects on the human body which may find prospects for disinfection and prevention of different diseases during the current pandemic time. Supplementary Information: The online version contains supplementary material available at 10.1007/s00339-022-06022-w.

7.
Mol Cell Biol ; 42(2): e0066920, 2022 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-34898280

RESUMO

Nucleophosmin (NPM1) is a multifunctional histone chaperone that can activate acetylation-dependent transcription from chromatin templates in vitro. p300-mediated acetylation of NPM1 has been shown to further enhance its transcription activation potential. Acetylated and total NPM1 pools are increased in oral squamous cell carcinoma. However, the role of NPM1 or its acetylated form (AcNPM1) in transcriptional regulation in cells and oral tumorigenesis is not fully elucidated. Using ChIP-seq analyses, we provide the first genome-wide profile of AcNPM1 and show that AcNPM1 is enriched at transcriptional regulatory elements. AcNPM1 co-occupies marks of active transcription at promoters and DNase I hypersensitive sites at enhancers. In addition, using a high-throughput protein interaction profiling approach, we show that NPM1 interacts with RNA Pol II, general transcription factors, mediator subunits, histone acetyltransferase complexes, and chromatin remodelers. NPM1 histone chaperone activity also contributes to its transcription activation potential. Further, NPM1 depletion leads to decreased AcNPM1 occupancy and reduced expression of genes required for proliferative, migratory and invasive potential of oral cancer cells. NPM1 depletion also abrogates the growth of orthotopic tumors in mice. Collectively, these results establish that AcNPM1 functions as a coactivator during during RNA polymerase II-driven transcription and regulates the expression of genes that promote oral tumorigenesis.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Regulação da Expressão Gênica/fisiologia , Chaperonas de Histonas/metabolismo , Neoplasias Bucais/genética , Nucleofosmina/metabolismo , Animais , Carcinogênese/metabolismo , Carcinoma de Células Escamosas/genética , Montagem e Desmontagem da Cromatina/genética , Montagem e Desmontagem da Cromatina/fisiologia , Regulação da Expressão Gênica/genética , Histonas/metabolismo , Humanos , Proteínas Nucleares/metabolismo , Regiões Promotoras Genéticas/genética
8.
Cells ; 10(10)2021 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-34685676

RESUMO

Long non-coding RNAs (lncRNAs) play key roles in Angiotensin II (AngII) signaling but their role in chondrogenic transformation of vascular smooth muscle cells (VSMCs) is unknown. We describe a novel AngII-induced lncRNA Alivec (Angiotensin II-induced lncRNA in VSMCs eliciting chondrogenic phenotype) implicated in VSMC chondrogenesis. In rat VSMCs, Alivec and the nearby gene Acan, a chondrogenic marker, were induced by growth factors AngII and PDGF and the inflammatory cytokine TNF-α. AngII co-regulated Alivec and Acan through the activation of AngII type1 receptor signaling and Sox9, a master transcriptional regulator of chondrogenesis. Alivec knockdown with GapmeR antisense-oligonucleotides attenuated the expression of AngII-induced chondrogenic marker genes, including Acan, and inhibited the chondrogenic phenotype of VSMCs. Conversely, Alivec overexpression upregulated these genes and promoted chondrogenic transformation. RNA-pulldown coupled to mass-spectrometry identified Tropomyosin-3-alpha and hnRNPA2B1 proteins as Alivec-binding proteins in VSMCs. Furthermore, male rats with AngII-driven hypertension showed increased aortic expression of Alivec and Acan. A putative human ortholog ALIVEC, was induced by AngII in human VSMCs, and this locus was found to harbor the quantitative trait loci affecting blood pressure. Together, these findings suggest that AngII-regulated lncRNA Alivec functions, at least in part, to mediate the AngII-induced chondrogenic transformation of VSMCs implicated in vascular dysfunction and hypertension.


Assuntos
Angiotensina II/farmacologia , Condrogênese/genética , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/metabolismo , RNA Longo não Codificante/metabolismo , Agrecanas/genética , Agrecanas/metabolismo , Animais , Aorta/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/genética , Condrogênese/efeitos dos fármacos , Elementos Facilitadores Genéticos/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/metabolismo , Humanos , Masculino , Contração Muscular/genética , Miócitos de Músculo Liso/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Fenótipo , Locos de Características Quantitativas/genética , RNA Longo não Codificante/genética , Ratos Sprague-Dawley , Receptor Tipo 1 de Angiotensina/genética , Receptor Tipo 1 de Angiotensina/metabolismo , Fatores de Transcrição SOX9/metabolismo , Tropomiosina/metabolismo , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética , Quinases da Família src/metabolismo
9.
Materials (Basel) ; 14(12)2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34207839

RESUMO

We report the surface stoichiometry of Tix-CuyNz thin film as a function of film depth. Films are deposited by high power impulse (HiPIMS) and DC magnetron sputtering (DCMS). The composition of Ti, Cu, and N in the deposited film is investigated by X-ray photoelectron spectroscopy (XPS). At a larger depth, the relative composition of Cu and Ti in the film is increased compared to the surface. The amount of adventitious carbon which is present on the film surface strongly decreases with film depth. Deposited films also contain a significant amount of oxygen whose origin is not fully clear. Grazing incidence X-ray diffraction (GIXD) shows a Cu3N phase on the surface, while transmission electron microscopy (TEM) indicates a polycrystalline structure and the presence of a Ti3CuN phase.

10.
JCI Insight ; 6(11)2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-33945509

RESUMO

Long noncoding RNAs (lncRNAs) are increasingly implicated in the pathology of diabetic complications. Here, we examined the role of lncRNAs in monocyte dysfunction and inflammation associated with human type 2 diabetes mellitus (T2D). RNA sequencing analysis of CD14+ monocytes from patients with T2D versus healthy controls revealed downregulation of antiinflammatory and antiproliferative genes, along with several lncRNAs, including a potentially novel divergent lncRNA diabetes regulated antiinflammatory RNA (DRAIR) and its nearby gene CPEB2. High glucose and palmitic acid downregulated DRAIR in cultured CD14+ monocytes, whereas antiinflammatory cytokines and monocyte-to-macrophage differentiation upregulated DRAIR via KLF4 transcription factor. DRAIR overexpression increased antiinflammatory and macrophage differentiation genes but inhibited proinflammatory genes. Conversely, DRAIR knockdown attenuated antiinflammatory genes, promoted inflammatory responses, and inhibited phagocytosis. DRAIR regulated target gene expression through interaction with chromatin, as well as inhibition of the repressive epigenetic mark H3K9me2 and its corresponding methyltransferase G9a. Mouse orthologous Drair and Cpeb2 were also downregulated in peritoneal macrophages from T2D db/db mice, and Drair knockdown in nondiabetic mice enhanced proinflammatory genes in macrophages. Thus, DRAIR modulates the inflammatory phenotype of monocytes/macrophages via epigenetic mechanisms, and its downregulation in T2D may promote chronic inflammation. Augmentation of endogenous lncRNAs like DRAIR could serve as novel antiinflammatory therapies for diabetic complications.


Assuntos
Diabetes Mellitus Tipo 2/genética , Monócitos/metabolismo , RNA Longo não Codificante/genética , Proteínas de Ligação a RNA/genética , Adulto , Animais , Diabetes Mellitus Tipo 2/metabolismo , Regulação para Baixo , Epigênese Genética , Feminino , Humanos , Inflamação/genética , Inflamação/metabolismo , Masculino , Camundongos , RNA Longo não Codificante/metabolismo , Proteínas de Ligação a RNA/metabolismo , Células THP-1 , Adulto Jovem
11.
ACS Omega ; 5(49): 31918-31924, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33344846

RESUMO

A comprehensive study on the electronic structure and optical properties of a Cu3N film is performed by the first-principles study using density functional theory. The Hubbard (U) term is added in the local density approximation approach for improvement of the theoretical band gap energy. The band structure of the Cu3N unit cell shows a strong hybridization of Cu 3d and N 2p orbitals in the near-valence band region (M) because of their antibonding states which are also observed by molecular orbitals (HOMO-LUMO). The conduction band is dominated by a very small amount of Cu 3p and N 2p orbitals. The density of states exhibits a negligible deformation in Cu-N bonding. The Cu3N thin film deposited by the DC magnetron-sputtering technique shows a polycrystalline structure with a nonstoichiometric Cu3N phase. The experimentally obtained optical band gap and refractive index of the Cu3N film are 1.44 eV and 2.14, respectively, which are comparable with those from the theoretical approximation.

13.
Curr Opin Cardiol ; 35(3): 234-241, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32205477

RESUMO

PURPOSE OF REVIEW: Hyperlipidemia, hypertension, diabetes and related metabolic disorders increase the risk for cardiovascular disease (CVD). Despite significant progress in the identification of key mechanisms and genetic polymorphisms linked to various CVDs, the rates of CVDs continue to escalate, underscoring the need to evaluate additional mechanisms for more effective therapies. Environment and lifestyle changes can alter epigenetic mechanisms mediated by histone modifications and long noncoding RNAs (lncRNAs) which play important roles in gene regulation. The review summarizes recent findings on the role of epigenetic mechanisms in CVD. RECENT FINDINGS: Recent studies identified dysregulated histone modifications and chromatin modifying proteins at cis-regulatory elements, including enhancers/super-enhancers, mediating the expression of genes associated with CVD in vascular and immune cells in response to growth factors and inflammatory mediators. Several lncRNAs have also been reported to contribute to pathological gene expression via cis and trans mechanisms involving interactions with nuclear proteins, co-operation with enhancers/super enhancers and acting as microRNA sponges. SUMMARY: Epigenomic approaches in cells affected in CVDs can be exploited to understand the function of genetic polymorphisms at cis-regulatory elements and crosstalk between enhancers and lncRNAs associated with disease susceptibility and progression. The reversible nature of epigenetics provides opportunities for the development of novel therapeutic strategies for CVD.


Assuntos
Doenças Cardiovasculares/genética , RNA Longo não Codificante/genética , Epigênese Genética , Humanos
14.
Arterioscler Thromb Vasc Biol ; 40(4): 914-928, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32078363

RESUMO

OBJECTIVE: Systemic low-grade inflammation associated with obesity and metabolic syndrome is a strong risk factor for the development of diabetes mellitus and associated cardiovascular complications. This inflammatory state is caused by release of proinflammatory cytokines by macrophages, especially in adipose tissue. Long noncoding RNAs regulate macrophage activation and inflammatory gene networks, but their role in macrophage dysfunction during diet-induced obesity has been largely unexplored. Approach and Results: We sequenced total RNA from peritoneal macrophages isolated from mice fed either high-fat diet or standard diet and performed de novo transcriptome assembly to identify novel differentially expressed mRNAs and long noncoding RNAs. A top candidate long noncoding RNA, macrophage inflammation-suppressing transcript (Mist), was downregulated in both peritoneal macrophages and adipose tissue macrophages from high-fat diet-fed mice. GapmeR-mediated Mist knockdown in vitro and in vivo upregulated expression of genes associated with immune response and inflammation and increased modified LDL (low-density lipoprotein) uptake in macrophages. Conversely, Mist overexpression decreased basal and LPS (lipopolysaccharide)-induced expression of inflammatory response genes and decreased modified LDL uptake. RNA-pull down coupled with mass spectrometry showed that Mist interacts with PARP1 (poly [ADP]-ribose polymerase-1). Disruption of this RNA-protein interaction increased PARP1 recruitment and chromatin PARylation at promoters of inflammatory genes, resulting in increased gene expression. Furthermore, human orthologous MIST was also downregulated by proinflammatory stimuli, and its expression in human adipose tissue macrophages inversely correlated with obesity and insulin resistance. CONCLUSIONS: Mist is a novel protective long noncoding RNA, and its loss during obesity contributes to metabolic dysfunction and proinflammatory phenotype of macrophages via epigenetic mechanisms.


Assuntos
Inflamação/fisiopatologia , Ativação de Macrófagos/genética , Obesidade/genética , Obesidade/fisiopatologia , RNA Longo não Codificante/fisiologia , Tecido Adiposo/metabolismo , Animais , Linhagem Celular , LDL-Colesterol/metabolismo , Cromatina/genética , Citocinas/fisiologia , Regulação para Baixo , Humanos , Metabolismo dos Lipídeos/genética , Masculino , Síndrome Metabólica/genética , Síndrome Metabólica/fisiopatologia , Camundongos Endogâmicos C57BL , Poli(ADP-Ribose) Polimerase-1/genética , Poli ADP Ribosilação , Regulação para Cima
15.
J Biol Chem ; 294(34): 12695-12707, 2019 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-31266808

RESUMO

Transforming growth factor-ß1 (TGF-ß)-induced fibrotic and inflammatory genes in renal mesangial cells (MCs) play important roles in glomerular dysfunction associated with diabetic nephropathy (DN). TGF-ß regulates gene expression in MCs by altering key chromatin histone modifications at target gene promoters. However, the role of the repressive histone H3 lysine 27 trimethylation (H3K27me3) modification is unclear. Here we show that TGF-ß reduces H3K27me3 at the Ctgf, Serpine1, and Ccl2 gene promoters in rat MCs (RMCs) and reciprocally up-regulates the expression of these pro-fibrotic and inflammatory genes. In parallel, TGF-ß down-regulates Enhancer of Zeste homolog 2 (Ezh2), an H3K27me3 methyltransferase, and decreases its recruitment at Ctgf and Ccl2 but not Serpine1 promoters. Ezh2 knockdown with siRNAs enhances TGF-ß-induced expression of these genes, supporting its repressive function. Mechanistically, Ezh2 down-regulation is mediated by TGF-ß-induced microRNA, miR-101b, which targets Ezh2 3'-UTR. TGF-ß also up-regulates Jmjd3 and Utx in RMCs, suggesting a key role for these H3K27me3 demethylases in H3K27me3 inhibition. In RMCs, Utx knockdown inhibits hypertrophy, a key event in glomerular dysfunction. The H3K27me3 regulators are similarly altered in human and mouse MCs. High glucose inhibits Ezh2 and increases miR-101b in a TGF-ß-dependent manner. Furthermore, in kidneys from rodent models of DN, fibrotic genes, miR-101b, and H3K27me3 demethylases are up-regulated, whereas Ezh2 protein levels as well as enrichment of Ezh2 and H3K27me3 at target genes are decreased, demonstrating in vivo relevance. These results suggest that H3K27me3 inhibition by TGF-ß via dysregulation of related histone-modifying enzymes and miRNAs augments pathological genes mediating glomerular mesangial dysfunction and DN.


Assuntos
Diabetes Mellitus Tipo 1/metabolismo , Nefropatias Diabéticas/metabolismo , Regulação da Expressão Gênica , Histonas/metabolismo , Lisina/metabolismo , Células Mesangiais/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Células Cultivadas , Diabetes Mellitus Tipo 1/induzido quimicamente , Diabetes Mellitus Tipo 1/genética , Nefropatias Diabéticas/induzido quimicamente , Nefropatias Diabéticas/genética , Humanos , Injeções Intraperitoneais , Masculino , Metilação , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Ratos Sprague-Dawley , Estreptozocina/administração & dosagem
16.
Circ Res ; 123(12): 1298-1312, 2018 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-30566058

RESUMO

RATIONALE: AngII (angiotensin II)-mediated vascular smooth muscle cell (VSMC) dysfunction plays a major role in hypertension. Long noncoding RNAs have elicited much interest, but their molecular roles in AngII actions and hypertension are unclear. OBJECTIVE: To investigate the regulation and functions of a novel long noncoding RNA growth factor- and proinflammatory cytokine-induced vascular cell-expressed RNA ( Giver), in AngII-mediated VSMC dysfunction. METHODS AND RESULTS: RNA-sequencing and real-time quantitative polymerase chain reactions revealed that treatment of rat VSMC with AngII increased the expression of Giver and Nr4a3, an adjacent gene encoding a nuclear receptor. Similar changes were observed in rat and mouse aortas treated ex vivo with AngII. RNA-FISH (fluorescence in situ hybridization) and subcellular fractionation showed predominantly nuclear localization of Giver. AngII increased Giver expression via recruitment of Nr4a3 to Giver promoter. Microarray profiling and real-time quantitative polymerase chain reaction validation in VSMC showed that Giver knockdown attenuated the expression of genes involved in oxidative stress ( Nox1) and inflammation ( Il6, Ccl2, Tnf) but increased Nr4a3. Conversely, endogenous Giver overexpression showed opposite effects supporting its role in oxidative stress and inflammation. Chromatin immunoprecipitation assays showed Giver overexpression also increased Pol II (RNA polymerase II) enrichment and decreased repressive histone modification histone H3 trimethylation on lysine 27 at Nox1 and inflammatory gene promoters. Accordingly, Giver knockdown inhibited AngII-induced oxidative stress and proliferation in rat VSMC. RNA-pulldown combined with mass spectrometry showed Giver interacts with nuclear and chromatin remodeling proteins and corepressors, including NONO (non-pou domain-containing octamer-binding protein). Moreover, NONO knockdown elicited similar effects as Giver knockdown on the expression of key Giver-regulated genes. Notably, GIVER and NR4A3 were increased in AngII-treated human VSMC and in arteries from hypertensive patients but attenuated in hypertensive patients treated with ACE (angiotensin-converting enzyme) inhibitors or angiotensin receptor blockers. Furthermore, human GIVER also exhibits partial functional conservation with rat Giver. CONCLUSIONS: Giver and its regulator Nr4a3 are important players in AngII-mediated VSMC dysfunction and could be novel targets for antihypertensive therapy.


Assuntos
Proliferação de Células , Citocinas/metabolismo , Hipertensão/metabolismo , Músculo Liso Vascular/metabolismo , Estresse Oxidativo , RNA Longo não Codificante/genética , Animais , Células Cultivadas , Humanos , Hipertensão/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Liso Vascular/citologia , Músculo Liso Vascular/fisiologia , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/fisiologia , NADPH Oxidase 1/genética , NADPH Oxidase 1/metabolismo , RNA Longo não Codificante/metabolismo , Ratos , Ratos Sprague-Dawley
17.
FEBS J ; 285(18): 3503-3524, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30085406

RESUMO

Nucleophosmin (NPM1) is a nucleolar protein that is frequently overexpressed in various types of solid tumors. NPM1 is involved in several cellular processes that might contribute significantly to the increased proliferation potential of cancers. Previous reports suggest that NPM1 expression is highly increased in response to mitogenic and oncogenic signals, the mechanisms of which have not been elucidated extensively. Using constructs incorporating different fragments of the NPM1 promoter upstream to a Luciferase reporter gene, we have identified the minimal promoter of NPM1 and candidate transcription factors regulating NPM1 promoter activity by luciferase reporter assays. We have validated the roles of a few candidate factors at the transcriptional and protein level by quantitative reverse transcriptase PCR, immunoblotting and immunohistochemistry, and explored the mechanism of regulation of NPM1 expression using immunoprecipitation and chromatin immunoprecipitation assays. We show here that the expression of NPM1 is regulated by transcription factor c-fos, a protein that is strongly activated by growth factor signals. In addition, mutant p53 (R175H) overexpression also enhances NPM1 expression possibly through c-myc and c-fos. Moreover, both c-fos and mutant p53 are overexpressed in oral tumor tissues that showed NPM1 overexpression. Collectively, our results suggest that c-fos and mutant p53 R175H positively regulate NPM1 expression, possibly in synergism, that might lead to oncogenic manifestation.


Assuntos
Carcinoma de Células Escamosas/patologia , Regulação Neoplásica da Expressão Gênica , Genes fos , Neoplasias Bucais/patologia , Mutação , Proteínas Nucleares/genética , Proteína Supressora de Tumor p53/metabolismo , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Proliferação de Células , Humanos , Neoplasias Bucais/genética , Neoplasias Bucais/metabolismo , Proteínas Nucleares/metabolismo , Nucleofosmina , Prognóstico , Regiões Promotoras Genéticas , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/genética
18.
Arterioscler Thromb Vasc Biol ; 38(8): 1806-1820, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29930005

RESUMO

Objective- Macrophages play key roles in inflammation and diabetic vascular complications. Emerging evidence implicates long noncoding RNAs in inflammation, but their role in macrophage dysfunction associated with inflammatory diabetic complications is unclear and was therefore investigated in this study. Approach and Results- RNA-sequencing and real-time quantitative PCR demonstrated that a long noncoding RNA Dnm3os (dynamin 3 opposite strand) is upregulated in bone marrow-derived macrophages from type 2 diabetic db/db mice, diet-induced insulin-resistant mice, and diabetic ApoE-/- mice, as well as in monocytes from type 2 diabetic patients relative to controls. Diabetic conditions (high glucose and palmitic acid) induced Dnm3os in mouse and human macrophages. Promoter reporter analysis and chromatin immunoprecipitation assays demonstrated that diabetic conditions induce Dnm3os via NF-κB activation. RNA fluorescence in situ hybridization and real-time quantitative PCRs of subcellular fractions demonstrated nuclear localization and chromatin enrichment of Dnm3os in macrophages. Stable overexpression of Dnm3os in macrophages altered global histone modifications and upregulated inflammation and immune response genes and phagocytosis. Conversely, RNAi-mediated knockdown of Dnm3os attenuated these responses. RNA pull-down assays with macrophage nuclear lysates identified nucleolin and ILF-2 (interleukin enhancer-binding factor 2) as protein binding partners of Dnm3os, which was further confirmed by RNA fluorescence in situ hybridization immunofluorescence. Furthermore, nucleolin levels were decreased in diabetic conditions, and its knockdown enhanced Dnm3os-induced inflammatory gene expression and histone H3K9-acetylation at their promoters. Conclusions- These results demonstrate novel mechanisms involving upregulation of long noncoding RNA Dnm3os, disruption of its interaction with nucleolin, and epigenetic modifications at target genes that promote macrophage inflammatory phenotype in diabetes mellitus. The data could lead to long noncoding RNA-based therapies for inflammatory diabetes mellitus complications.


Assuntos
Núcleo Celular/metabolismo , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Inflamação/metabolismo , Ativação de Macrófagos , Macrófagos/metabolismo , RNA Longo não Codificante/metabolismo , Animais , Estudos de Casos e Controles , Núcleo Celular/genética , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Tipo 1/induzido quimicamente , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 2/genética , Epigênese Genética , Feminino , Humanos , Inflamação/genética , Mediadores da Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Fagocitose , Fenótipo , Fosfoproteínas/metabolismo , Ligação Proteica , Células RAW 264.7 , RNA Longo não Codificante/genética , Proteínas de Ligação a RNA/metabolismo , Transdução de Sinais , Estreptozocina , Regulação para Cima , Nucleolina
19.
Nat Commun ; 8(1): 1467, 2017 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-29133788

RESUMO

Angiotensin II (AngII) promotes hypertension and atherosclerosis by activating growth-promoting and pro-inflammatory gene expression in vascular smooth muscle cells (VSMCs). Enhancers and super-enhancers (SEs) play critical roles in driving disease-associated gene expression. However, enhancers/SEs mediating VSMC dysfunction remain uncharacterized. Here, we show that AngII alters vascular enhancer and SE repertoires in cultured VSMCs in vitro, ex vivo, and in AngII-infused mice aortas in vivo. AngII-induced enhancers/SEs are enriched in binding sites for signal-dependent transcription factors and dependent on key signaling kinases. Moreover, CRISPR-Cas9-mediated deletion of candidate enhancers/SEs, targeting SEs with the bromodomain and extra-terminal domain inhibitor JQ1, or knockdown of overlapping long noncoding RNAs (lncRNAs) blocks AngII-induced genes associated with growth-factor signaling and atherosclerosis. Furthermore, JQ1 ameliorates AngII-induced hypertension, medial hypertrophy and inflammation in vivo in mice. These results demonstrate AngII-induced signals integrate enhancers/SEs and lncRNAs to increase expression of genes involved in VSMC dysfunction, and could uncover novel therapies.


Assuntos
Angiotensina II/metabolismo , Aterosclerose/genética , Hipertensão/genética , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/patologia , RNA Longo não Codificante/genética , Animais , Aorta/citologia , Aorta/patologia , Aterosclerose/tratamento farmacológico , Azepinas/farmacologia , Células Cultivadas , Regulação da Expressão Gênica , Histonas/metabolismo , Hipertensão/tratamento farmacológico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/genética , Triazóis/farmacologia
20.
Sci Rep ; 7(1): 9017, 2017 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-28827664

RESUMO

Nucleolin is an essential protein that plays important roles in the regulation of cell cycle and cell proliferation. Its expression is up regulated in many cancer cells but its molecular functions are not well characterized. Nucleolin is present in the nucleus where it regulates gene expression at the transcriptional and post-transcriptional levels. Using HeLa cells depleted in nucleolin we performed an mRNA and miRNA transcriptomics analysis to identify biological pathways involving nucleolin. Bioinformatic analysis strongly points to a role of nucleolin in lipid metabolism, and in many signaling pathways. Down regulation of nucleolin is associated with lower level of cholesterol while the amount of fatty acids is increased. This could be explained by the decreased and mis-localized expression of the transcription factor SREBP1 and the down-regulation of enzymes involved in the beta-oxidation and degradation of fatty acids. Functional classification of the miRNA-mRNA target genes revealed that deregulated miRNAs target genes involved in apoptosis, proliferation and signaling pathways. Several of these deregulated miRNAs have been shown to control lipid metabolism. This integrated transcriptomic analysis uncovers new unexpected roles for nucleolin in metabolic regulation and signaling pathways paving the way to better understand the global function of nucleolin within the cell.


Assuntos
Perfilação da Expressão Gênica , MicroRNAs/análise , Fosfoproteínas/metabolismo , RNA Mensageiro/análise , Proteínas de Ligação a RNA/metabolismo , Biologia Computacional , Regulação da Expressão Gênica , Células HeLa , Humanos , Metabolismo dos Lipídeos , MicroRNAs/genética , RNA Mensageiro/genética , Transdução de Sinais , Nucleolina
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