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1.
Int J Mol Sci ; 23(23)2022 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-36499116

RESUMO

Alzheimer's disease (AD) is a progressive and complex neurodegenerative disease. Acetylcholinesterase inhibitors (AChEIs) are a major class of drugs used in AD therapy. ROCK2, another promising target for AD, has been associated with the induction of neurogenesis via PTEN/AKT. This study aimed to characterize the therapeutic potential of a novel donepezil-tacrine hybrid compound (TA8Amino) to inhibit AChE and ROCK2 protein, leading to the induction of neurogenesis in SH-SY5Y cells. Experiments were carried out with undifferentiated and neuron-differentiated SH-SY5Y cells submitted to treatments with AChEIs (TA8Amino, donepezil, and tacrine) for 24 h or 7 days. TA8Amino was capable of inhibiting AChE at non-cytotoxic concentrations after 24 h. Following neuronal differentiation for 7 days, TA8Amino and donepezil increased the percentage of neurodifferentiated cells and the length of neurites, as confirmed by ß-III-tubulin and MAP2 protein expression. TA8Amino was found to participate in the activation of PTEN/AKT signaling. In silico analysis showed that TA8Amino can stably bind to the active site of ROCK2, and in vitro experiments in SH-SY5Y cells demonstrate that TA8Amino significantly reduced the expression of ROCK2 protein, contrasting with donepezil and tacrine. Therefore, these results provide important information on the mechanism underlying the action of TA8Amino with regard to multi-target activities.


Assuntos
Doença de Alzheimer , Inibidores da Colinesterase , Neuroblastoma , Doenças Neurodegenerativas , Quinases Associadas a rho , Humanos , Acetilcolinesterase/metabolismo , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Inibidores da Colinesterase/química , Donepezila/farmacologia , Neuroblastoma/tratamento farmacológico , Doenças Neurodegenerativas/tratamento farmacológico , PTEN Fosfo-Hidrolase , Quinases Associadas a rho/antagonistas & inibidores , Tacrina/química
3.
Front Immunol ; 13: 948419, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36148232

RESUMO

The autoimmune regulator (AIRE) protein functions as a tetramer, interacting with partner proteins to form the "AIRE complex," which relieves RNA Pol II stalling in the chromatin of medullary thymic epithelial cells (mTECs). AIRE is the primary mTEC transcriptional controller, promoting the expression of a large set of peripheral tissue antigen genes implicated in the negative selection of self-reactive thymocytes. Under normal conditions, the SIRT1 protein temporarily interacts with AIRE and deacetylates K residues of the AIRE SAND domain. Once the AIRE SAND domain is deacetylated, the binding with SIRT1 is undone, allowing the AIRE complex to proceed downstream with the RNA Pol II to the elongation phase of transcription. Considering that the in silico and in vitro binding of the AIRE SAND domain with SIRT1 provides a powerful model system for studying the dominant SAND G228W mutation mechanism, which causes the autoimmune polyglandular syndrome-1, we integrated computational molecular modeling, docking, dynamics between the whole SAND domain with SIRT1, and surface plasmon resonance using a peptide harboring the 211 to 230 residues of the SAND domain, to compare the structure and energetics of binding/release between AIRE G228 (wild-type) and W228 (mutant) SAND domain to SIRT1. We observed that the G228W mutation in the SAND domain negatively influences the AIRE-SIRT1 interaction. The disturbed interaction might cause a disruption in the binding of the AIRE SAND domain with the SIRT1 catalytic site, impairing the AIRE complex to proceed downstream with RNA Pol II.


Assuntos
RNA Polimerase II , Sirtuína 1 , Cromatina , Regulação da Expressão Gênica , Mutação , Peptídeos , Sirtuína 1/genética
4.
BMC Genomics ; 23(1): 404, 2022 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-35643451

RESUMO

BACKGROUND: The autoimmune regulator (Aire) gene is critical for the appropriate establishment of central immune tolerance. As one of the main controllers of promiscuous gene expression in the thymus, Aire promotes the expression of thousands of downstream tissue-restricted antigen (TRA) genes, cell adhesion genes and transcription factor genes in medullary thymic epithelial cells (mTECs). Despite the increasing knowledge about the role of Aire as an upstream transcriptional controller, little is known about the mechanisms by which this gene could be regulated. RESULTS: Here, we assessed the posttranscriptional control of Aire by miRNAs. The in silico miRNA-mRNA interaction analysis predicted thermodynamically stable hybridization between the 3'UTR of Aire mRNA and miR-155, which was confirmed to occur within the cellular milieu through a luciferase reporter assay. This finding enabled us to hypothesize that miR-155 might play a role as an intracellular posttranscriptional regulator of Aire mRNA. To test this hypothesis, we transfected a murine mTEC cell line with a miR-155 mimic in vitro, which reduced the mRNA and protein levels of Aire. Moreover, large-scale transcriptome analysis showed the modulation of 311 downstream mRNAs, which included 58 TRA mRNAs. Moreover, miR-155 mimic-transfected cells exhibited a decrease in their chemotaxis property compared with control thymocytes. CONCLUSION: Overall, the results indicate that miR-155 may posttranscriptionally control Aire mRNA, reducing the respective Aire protein levels; consequently, the levels of mRNAs encode tissue-restricted antigens were affected. In addition, miR-155 regulated a crucial process by which mTECs allow thymocytes' migration through chemotaxis.


Assuntos
MicroRNAs , Fatores de Transcrição , Animais , Células Epiteliais/metabolismo , Camundongos , MicroRNAs/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Transcrição/metabolismo , Proteína AIRE
5.
BMC Mol Cell Biol ; 23(1): 15, 2022 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-35331137

RESUMO

BACKGROUND: Besides controlling the expression of peripheral tissue antigens, the autoimmune regulator (AIRE) gene also regulates the expression of adhesion genes in medullary thymic epithelial cells (mTECs), an essential process for mTEC-thymocyte interaction for triggering the negative selection in the thymus. For these processes to occur, it is necessary that the medulla compartment forms an adequate three-dimensional (3D) architecture, preserving the thymic medulla. Previous studies have shown that AIRE knockout (KO) mice have a small and disorganized thymic medulla; however, whether AIRE influences the mTEC-mTEC interaction in the maintenance of the 3D structure has been little explored. Considering that AIRE controls cell adhesion genes, we hypothesized that this gene affects 3D mTEC-mTEC interaction. To test this, we constructed an in vitro model system for mTEC spheroid formation, in which cells adhere to each other, establishing a 3D structure. RESULTS: The comparisons between AIRE wild type (AIREWT) and AIRE KO (AIRE-/-) 3D mTEC spheroid formation showed that the absence of AIRE: i) disorganizes the 3D structure of mTEC spheroids, ii) increases the proportion of cells at the G0/G1 phase of the cell cycle, iii) increases the rate of mTEC apoptosis, iv) decreases the strength of mTEC-mTEC adhesion, v) promotes a differential regulation of mTEC classical surface markers, and vi) modulates genes encoding adhesion and other molecules. CONCLUSIONS: Overall, the results show that AIRE influences the 3D structuring of mTECs when these cells begin the spheroid formation through controlling cell adhesion genes.


Assuntos
Células Epiteliais , Genes Reguladores , Animais , Adesão Celular , Diferenciação Celular/genética , Células Epiteliais/metabolismo , Camundongos , Camundongos Knockout
6.
Mol Immunol ; 140: 127-135, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34700158

RESUMO

The autoimmune regulator (Aire) gene in medullary thymic epithelial cells (mTECs) encodes the AIRE protein, which interacts with its partners within the nucleus. This "Aire complex" induces stalled RNA Pol II on chromatin to proceed with transcription elongation of a large set of messenger RNAs and microRNAs. Considering that RNA Pol II also transcribes long noncoding RNAs (lncRNAs), we hypothesized that Aire might be implicated in the upstream control of this RNA species. To test this, we employed a loss-of-function approach in which Aire knockout mTECs were compared to Aire wild-type mTECs for lncRNA transcriptional profiling both in vitro and in vivo model systems. RNA sequencing enables the differential expression profiling of lncRNAs when these cells adhere in vitro to thymocytes or do not adhere to them as a way to test the effect of cell adhesion. Sets of lncRNAs that are unique and that are shared in vitro and in vivo were identified. Among these, we found the Aire-dependent lncRNAs as for example, Platr28, Ifi30, Morrbid, Malat1, and Xist. This finding represents the first evidence that Aire mediates the transcription of lncRNAs in mTECs. Microarray hybridizations enabled us to observe that temporal thymocyte adhesion modulates the expression levels of such lncRNAs as Morrbid, Xist, and Fbxl12o after 36 h of adhesion. This finding shows the existence of a synergistic mechanism involving a link between thymocyte adhesion, Aire, and lncRNAs in mTECs that might be important for immune self-representation.


Assuntos
Células Epiteliais/metabolismo , RNA Longo não Codificante/metabolismo , Timócitos/citologia , Timo/citologia , Fatores de Transcrição/metabolismo , Animais , Adesão Celular , Linhagem Celular , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Camundongos Endogâmicos C57BL , Fases de Leitura Aberta/genética , RNA Longo não Codificante/genética , Fatores de Tempo , Transcrição Gênica , Proteína AIRE
7.
Crit Rev Immunol ; 41(6): v, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35695642

RESUMO

Body homeostasis, immune response to microbial infections or vaccination, control of cancer onset or autoimmune or inflammatory diseases, as well as autism or other behavioral disorders, among other examples, are now recognized to be associated with the complex constitution of the body's microbiome. Recent findings demonstrate that the microbial composition, i.e., pathogenic, symbionts, and commensal viruses, bacteria, or yeast mainly in the gut, is strongly associated with susceptibility/resistance to several classes of diseases or its therapeutic response. This Special Issue focuses on the processes that link the human microbiome to three classes of diseases; immunodeficiency, autoimmunity, and cancer. Review articles cover aspects of the recent progress in selective immunoglobulin A (IgA) deficiency, Sjörgren's syndrome, breast cancer.


Assuntos
Microbioma Gastrointestinal , Microbiota , Autoimunidade , Humanos , Deficiência de IgA , Sistema Imunitário
8.
Mol Immunol ; 114: 600-611, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31539668

RESUMO

In this work, we demonstrate that adhesion between medullary thymic epithelial cells (mTECs) and thymocytes is controlled by miRNAs. Adhesion between mTECs and developing thymocytes is essential for triggering negative selection (NS) of autoreactive thymocytes that occurs in the thymus. Immune recognition is mediated by the MHC / TCR receptor, whereas adhesion molecules hold cell-cell interaction stability. Indeed, these processes must be finely controlled, if it is not, it may lead to aggressive autoimmunity. Conversely, the precise molecular genetic control of mTEC-thymocyte adhesion is largely unclear. Here, we asked whether miRNAs would be controlling this process through the posttranscriptional regulation of mRNAs that encode adhesion molecules. For this, we used small interfering RNA to knockdown (KD) Dicer mRNA in vitro in a murine mTEC line. A functional assay with fresh murine thymocytes co-cultured with mTECs showed that single-positive (SP) CD4 and CD8 thymocyte adhesion was increased after Dicer KD and most adherent subtype was CD8 SP cells. Analysis of broad mTEC transcriptional expression showed that Dicer KD led to the modulation of 114 miRNAs and 422 mRNAs, including those encoding cell adhesion or extracellular matrix proteins, such as Lgals9, Lgals3pb, Tnc and Cd47. Analysis of miRNA-mRNA networks followed by miRNA mimic transfection showed that these mRNAs are under the control of miR-181b-5p and miR-30b*, which may ultimately control mTEC-thymocyte adhesion. The expression of CD80 surface marker in mTECs was increased after Dicer KD following thymocyte adhesion. This indicates the existence of new mechanisms in mTECs that involve the synergistic action of thymocyte adhesion and regulatory miRNAs.


Assuntos
Adesão Celular/imunologia , Células Epiteliais/imunologia , MicroRNAs/imunologia , Timócitos/imunologia , Timo/imunologia , Animais , Antígeno B7-1/imunologia , Biomarcadores/sangue , Diferenciação Celular/imunologia , Feminino , Regulação da Expressão Gênica/imunologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Receptores de Antígenos de Linfócitos T/imunologia , Tolerância a Antígenos Próprios/imunologia , Fatores de Transcrição/imunologia
9.
Immunology ; 158(2): 121-135, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31322727

RESUMO

The Autoimmune Regulator (Aire) protein coordinates the negative selection of developing thymocytes by inducing the expression of hundreds of tissue-specific antigens within the thymic medulla, which is also a primary site of the expression of the immune checkpoint HLA-G molecule. Considering the immunomodulatory properties of Aire and HLA-G, and considering that the role of the constitutive thymus expression of HLA-G has not been elucidated, we studied the effect of AIRE cDNA transfection on HLA-G expression in 4D6 thymic cells and in the HLA-G-positive JEG-3 choriocarcinoma cells. Aire promoted the transactivation of HLA-G gene by increasing the overall transcription, inducing the transcription of at least G1 and G2/G4 isoforms, and incrementing the occurrence and distribution of intracellular HLA-G protein solely in 4D6 thymic cells. Luciferase-based assays and chromatin immunoprecipitation experiments performed in 4D6 cells revealed that Aire targeted at least two regions within the 5'-untranslated regulatory region (5'-URR) extending 1·4 kb from the first ATG initiation codon. The interaction occurs independently of three putative Aire-binding sites. These results indicate that the Aire-induced upregulation of HLA-G in thymic cells is likely to act through the interaction of Aire with specific HLA-G 5'-URR DNA-binding factors. Such a multimeric transcriptional complex might operate in the thymus during the process of promiscuous gene expression.


Assuntos
Células Epiteliais/imunologia , Antígenos HLA-G/genética , Fatores de Transcrição/genética , Ativação Transcricional/imunologia , Regiões 5' não Traduzidas , Autoimunidade/genética , Sítios de Ligação , Linhagem Celular Tumoral , Células Epiteliais/citologia , Genes Reporter , Antígenos HLA-G/imunologia , Humanos , Luciferases/genética , Luciferases/metabolismo , Plasmídeos/química , Plasmídeos/metabolismo , Ligação Proteica , Transdução de Sinais , Timo/citologia , Timo/imunologia , Fatores de Transcrição/imunologia , Transfecção , Proteína AIRE
10.
BMC Genomics ; 20(1): 411, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31117938

RESUMO

BACKGROUND: Trichophyton rubrum is the main etiological agent of skin and nail infections worldwide. Because of its keratinolytic activity and anthropophilic nature, infection models based on the addition of protein substrates have been employed to assess transcriptional profiles and to elucidate aspects related to host-pathogen interactions. Chalcones are widespread compounds with pronounced activity against dermatophytes. The toxicity of trans-chalcone towards T. rubrum is not fully understood but seems to rely on diverse cellular targets. Within this context, a better understanding of the mode of action of trans-chalcone may help identify new strategies of antifungal therapy and reveal new chemotherapeutic targets. This work aimed to assess the transcriptional profile of T. rubrum grown on different protein sources (keratin or elastin) to mimic natural infection sites and exposed to trans-chalcone in order to elucidate the mechanisms underlying the antifungal activity of trans-chalcone. RESULTS: Overall, the use of different protein sources caused only slight differences in the transcriptional profile of T. rubrum. The main differences were the modulation of proteases and lipases in gene categories when T. rubrum was grown on keratin and elastin, respectively. In addition, some genes encoding heat shock proteins were up-regulated during the growth of T. rubrum on keratin. The transcriptional profile of T. rubrum exposed to trans-chalcone included four main categories: fatty acid and lipid metabolism, overall stress response, cell wall integrity pathway, and alternative energy metabolism. Consistently, T. rubrum Mapk was strongly activated during the first hours of trans-chalcone exposure. Noteworthy, trans-chalcone inhibited genes involved in keratin degradation. The results also showed effects of trans-chalcone on fatty acid synthesis and metabolic pathways involved in acetyl-CoA supply. CONCLUSION: Our results suggest that the mode of action of trans-chalcone is related to pronounced changes in fungal metabolism, including an imbalance between fatty acid synthesis and degradation that interferes with cell membrane and cell wall integrity. In addition, this compound exerts activity against important virulence factors. Taken together, trans-chalcone acts on targets related to dermatophyte physiology and the infection process.


Assuntos
Parede Celular/química , Chalcona/farmacologia , Ácidos Graxos/metabolismo , Proteínas Fúngicas/metabolismo , Tinha/metabolismo , Trichophyton/metabolismo , Fatores de Virulência/antagonistas & inibidores , Antifúngicos/farmacologia , Parede Celular/genética , Elastina/metabolismo , Proteínas Fúngicas/genética , Perfilação da Expressão Gênica , Regulação Fúngica da Expressão Gênica , Humanos , Queratinas/metabolismo , Transdução de Sinais , Tinha/tratamento farmacológico , Tinha/microbiologia , Trichophyton/efeitos dos fármacos , Trichophyton/genética
11.
Mol Cell Endocrinol ; 490: 1-14, 2019 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-30926524

RESUMO

The delayed diagnosis and the inadequate treatment of diabetes increase the risk of chronic complications. The study of regulatory molecules such as miRNAs can provide expression profiles of diabetes and diabetes complications. We evaluated the mononuclear cell miRNA profiles of 63 Type 1 and Type 2 diabetes patients presenting or not microvascular complications, and 40 healthy controls, using massive parallel sequencing. Gene targets, enriched pathways, dendograms and miRNA-mRNA networks were performed for the differentially expressed miRNAs. Six more relevant miRNAs were validated by RT-qPCR and data mining analysis. MiRNAs associated with specific complications included: i) neuropathy (miR-873-5p, miR-125a-5p, miR-145-3p and miR-99b-5p); ii) nephropathy (miR-1249-3p, miR-193a-5p, miR-409-5p, miR-1271-5p, miR-501-3p, miR-148b-3p and miR-9-5p); and iii) retinopathy (miR-143-3p, miR-1271-5p, miR-409-5p and miR-199a-5p). These miRNAs mainly targeted gene families and specific genes associated with advanced glycation end products and their receptors. Sets of miRNAs were also defined as potential targets for diabetes/diabetes complication pathogenesis.


Assuntos
Biomarcadores/metabolismo , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Transcrição Gênica , Adolescente , Adulto , Idoso , Análise por Conglomerados , Mineração de Dados , Feminino , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Adulto Jovem
12.
J Cell Biochem ; 120(7): 11842-11852, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30746760

RESUMO

Mesenchymal stem cells (MSCs) have been used in therapies for bone tissue healing. The aim of this study was to investigate the effect of cell source and osteoblast differentiation on gene expression profiles of MSCs from bone marrow (BM-MSCs) or adipose tissue (AT-MSCs) to contribute for selecting a suitable cell population to be used in cell-based strategies for bone regeneration. BM-MSCs and AT-MSCs were cultured in growth medium to keep MSCs characteristics or in osteogenic medium to induce osteoblast differentiation (BM-OBs and AT-OBs). The transcriptomic analysis was performed by microarray covering the entire rat functional genome. It was observed that cells from bone marrow presented higher expression of genes related to osteogenesis, whereas cells from adipose tissue showed a higher expression of genes related to angiogenesis and adipocyte differentiation, irrespective of cell differentiation. By comparing cells from the same source, MSCs from both sources exhibited higher expression of genes involved in angiogenesis, osteoblast differentiation, and bone morphogenesis than osteoblasts. The clustering analysis showed that AT-OBs exhibited a gene expression profile closer to MSCs from both sources than BM-OBs, suggesting that BM-OBs were in a more advanced stage of differentiation. In conclusion, our results suggest that in cell-based therapies for bone regeneration AT-MSCs could be considered for angiogenic purposes, whereas BM-MSCs and osteoblasts differentiated from either source could be better for osteogenic approaches.

13.
Cell Biol Int ; 42(1): 12-24, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28574187

RESUMO

Investigation on functional genome research may contribute to the knowledge of functional roles of different mRNAs and miRNAs in bone cells of osteoporotic animals. Currently, few studies indicate the changes in gene modulation that osteoporosis causes in osteoblastic cells from different sites. Thus, the purpose of this investigation was to evaluate cell viability, alkaline phosphatase activity and modulation of mRNAs/miRNAs in osteoblastic cells from calvaria and bone marrow by means of microarray technology. Wistar female rats were divided in sham operated and ovariectomized groups. After 150 days of ovariectomy, cells were isolated from both sites to perform cell culture. Results showed that calvaria cells from ovariectomized rats had a decrease in viability when compared to control groups and to bone marrow cells from osteoporotic rats after 3 days. Alkaline phosphatase activity decreased in calvaria cells from ovariectomized rats whereas it was increased in bone marrow osteoblastic cells in the same group. Microarray data analysis showed 5447 differentially expressed mRNAs and 82 differentially expressed miRNAs in calvaria cells. The same way, 4399 mRNAs and 54 miRNAs were expressed in bone marrow cells. mRNAs associated with bone metabolism such as Anxa5, Sp7, Spp1, Notch1 were distinctively modulated in both sites, as well as miRNAs such as miR-350, miR-542-3p, miR-204-5p, and miR-30e-3p. The RNA species identified in this study could be further used as targets for treatment or prevention of osteoporosis.


Assuntos
Células da Medula Óssea/metabolismo , Menopausa/metabolismo , Fosfatase Alcalina/metabolismo , Animais , Medula Óssea/metabolismo , Diferenciação Celular/genética , Feminino , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/metabolismo , Osteoporose/metabolismo , Ovariectomia/métodos , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Crânio/metabolismo , Transcriptoma/genética
14.
PLoS One ; 11(10): e0163855, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27695061

RESUMO

The involvement of miRNA in mesial temporal lobe epilepsy (MTLE) pathogenesis has increasingly become a focus of epigenetic studies. Despite advances, the number of known miRNAs with a consistent expression response during epileptogenesis is still small. Addressing this situation requires additional miRNA profiling studies coupled to detailed individual expression analyses. Here, we perform a miRNA microarray analysis of the hippocampus of Wistar rats 24 hours after intra-hippocampal pilocarpine-induced Status Epilepticus (H-PILO SE). We identified 73 miRNAs that undergo significant changes, of which 36 were up-regulated and 37 were down-regulated. To validate, we selected 5 of these (10a-5p, 128a-3p, 196b-5p, 352 and 324-3p) for RT-qPCR analysis. Our results confirmed that miR-352 and 196b-5p levels were significantly higher and miR-128a-3p levels were significantly lower in the hippocampus of H-PILO SE rats. We also evaluated whether the 3 miRNAs show a dysregulated hippocampal expression at three time periods (0h, 24h and chronic phase) after systemic pilocarpine-induced status epilepticus (S-PILO SE). We demonstrate that miR-128a-3p transcripts are significantly reduced at all time points compared to the naïve group. Moreover, miR-196b-5p was significantly higher only at 24h post-SE, while miR-352 transcripts were significantly up-regulated after 24h and in chronic phase (epileptic) rats. Finally, when we compared hippocampi of epileptic and non-epileptic humans, we observed that transcript levels of miRNAs show similar trends to the animal models. In summary, we successfully identified two novel dysregulated miRNAs (196b-5p and 352) and confirmed miR-128a-3p downregulation in SE-induced epileptogenesis. Further functional assays are required to understand the role of these miRNAs in MTLE pathogenesis.


Assuntos
Epilepsia do Lobo Temporal/genética , MicroRNAs/biossíntese , Estado Epiléptico/genética , Animais , Modelos Animais de Doenças , Epilepsia do Lobo Temporal/induzido quimicamente , Epilepsia do Lobo Temporal/patologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/genética , Giro do Cíngulo/metabolismo , Giro do Cíngulo/patologia , Humanos , Masculino , MicroRNAs/genética , Análise de Sequência com Séries de Oligonucleotídeos , Pilocarpina/toxicidade , Ratos , Ratos Wistar , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/patologia
15.
Mol Immunol ; 77: 157-73, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27505711

RESUMO

We demonstrate that even a partial reduction of Aire mRNA levels by siRNA-induced Aire knockdown (Aire KD) has important consequences to medullary thymic epithelial cells (mTECs). Aire knockdown is sufficient to reduce Aire protein levels, impair its nuclear location, and cause an imbalance in large-scale gene expression, including genes that encode cell adhesion molecules. These genes drew our attention because adhesion molecules are implicated in the process of mTEC-thymocyte adhesion, which is critical for T cell development and the establishment of central self-tolerance. Accordingly, we consider the following: 1) mTECs contribute to the elimination of self-reactive thymocytes through adhesion; 2) Adhesion molecules play a crucial role during physical contact between these cells; and 3) Aire is an important transcriptional regulator in mTECs. However, its role in controlling mTEC-thymocyte adhesion remains unclear. Because Aire controls adhesion molecule genes, we hypothesized that the disruption of its expression could influence mTEC-thymocyte interaction. To test this hypothesis, we used a murine Aire(+) mTEC cell line as a model system to reproduce mTEC-thymocyte adhesion in vitro. Transcriptome analysis of the mTEC cell line revealed that Aire KD led to the down-modulation of more than 800 genes, including those encoding for proteins involved in cell adhesion, i.e., the extracellular matrix constituent Lama1, the CAM family adhesion molecules Vcam1 and Icam4, and those that encode peripheral tissue antigens. Thymocytes co-cultured with Aire KD mTECs had a significantly reduced capacity to adhere to these cells. This finding is the first direct evidence that Aire also plays a role in controlling mTEC-thymocyte adhesion.


Assuntos
Adesão Celular/imunologia , Células Epiteliais/citologia , Timócitos/citologia , Timo/citologia , Fatores de Transcrição/metabolismo , Animais , Western Blotting , Diferenciação Celular/imunologia , Células Epiteliais/imunologia , Células Epiteliais/metabolismo , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/imunologia , Técnicas de Silenciamento de Genes , Hibridização in Situ Fluorescente , Camundongos , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase , Tolerância a Antígenos Próprios/imunologia , Timócitos/imunologia , Timócitos/metabolismo , Timo/imunologia , Timo/metabolismo , Fatores de Transcrição/imunologia , Transcriptoma/imunologia , Proteína AIRE
17.
Front Immunol ; 6: 352, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26236310

RESUMO

Developing thymocytes interact sequentially with two distinct structures within the thymus: the cortex and medulla. Surviving single-positive and double-positive thymocytes from the cortex migrate into the medulla, where they interact with medullary thymic epithelial cells (mTECs). These cells ectopically express a vast set of peripheral tissue antigens (PTAs), a property termed promiscuous gene expression that is associated with the presentation of PTAs by mTECs to thymocytes. Thymocyte clones that have a high affinity for PTAs are eliminated by apoptosis in a process termed negative selection, which is essential for tolerance induction. The Aire gene is an important factor that controls the expression of a large set of PTAs. In addition to PTAs, Aire also controls the expression of miRNAs in mTECs. These miRNAs are important in the organization of the thymic architecture and act as posttranscriptional controllers of PTAs. Herein, we discuss recent discoveries and highlight open questions regarding the migration and interaction of developing thymocytes with thymic stroma, the ectopic expression of PTAs by mTECs, the association between Aire and miRNAs and its effects on central tolerance.

18.
J Immunol Res ; 2014: 159247, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24829926

RESUMO

Qa-2 and Qa-1 are murine nonclassical MHC class I molecules involved in the modulation of immune responses by interacting with T CD8(+) and NK cell inhibitory receptors. During thymic education, the Aire gene imposes the expression of thousands of tissue-related antigens in the thymic medulla, permitting the negative selection events. Aiming to characterize the transcriptional profiles of nonclassical MHC class I genes in spatial-temporal association with the Aire expression, we evaluated the gene expression of H2-Q7(Qa-2), H2-T23(Qa-1), H2-Q10(Qa-10), and Aire during fetal and postnatal development of thymus and other tissues. In the thymus, H2-Q7(Qa-2) transcripts were detected at high levels throughout development and were positively correlated with Aire expression during fetal ages. H2-Q7(Qa-2) and H2-T23(Qa-1) showed distinct expression patterns with gradual increasing levels according to age in most tissues analyzed. H2-Q10(Qa-10) was preferentially expressed by the liver. The Aire transcriptional profile showed increased levels during the fetal period and was detectable in postnatal ages in the thymus. Overall, nonclassical MHC class I genes started to be expressed early during the ontogeny. Their levels varied according to age, tissue, and mouse strain analyzed. This differential expression may contribute to the distinct patterns of mouse susceptibility/resistance to infectious and noninfectious disorders.


Assuntos
Regulação da Expressão Gênica , Antígenos de Histocompatibilidade Classe I/genética , Timo/metabolismo , Fatores de Transcrição/genética , Transcriptoma , Animais , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Antígenos H-2/genética , Antígenos H-2/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Tecido Linfoide/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Especificidade de Órgãos/genética , Timo/imunologia , Proteína AIRE
19.
J Rheumatol ; 39(8): 1524-32, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22753658

RESUMO

OBJECTIVE: We aimed to evaluate whether the differential gene expression profiles of patients with rheumatoid arthritis (RA) could distinguish responders from nonresponders to methotrexate (MTX) and, in the case of MTX nonresponders, responsiveness to MTX plus anti-tumor necrosis factor-α (anti-TNF) combined therapy. METHODS: We evaluated 25 patients with RA taking MTX 15-20 mg/week as a monotherapy (8 responders and 17 nonresponders). All MTX nonresponders received infliximab and were reassessed after 20 weeks to evaluate their anti-TNF responsiveness using the European League Against Rheumatism response criteria. A differential gene expression analysis from peripheral blood mononuclear cells was performed in terms of hierarchical gene clustering, and an evaluation of differentially expressed genes was performed using the significance analysis of microarrays program. RESULTS: Hierarchical gene expression clustering discriminated MTX responders from nonresponders, and MTX plus anti-TNF responders from nonresponders. The evaluation of only highly modulated genes (fold change > 1.3 or < 0.7) yielded 5 induced (4 antiapoptotic and CCL4) and 4 repressed (4 proapoptotic) genes in MTX nonresponders compared to responders. In MTX plus anti-TNF non-responders, the CCL4, CD83, and BCL2A1 genes were induced in relation to responders. CONCLUSION: Study of the gene expression profiles of RA peripheral blood cells permitted differentiation of responders from nonresponders to MTX and anti-TNF. Several candidate genes in MTX non-responders (CCL4, HTRA2, PRKCD, BCL2A1, CAV1, TNIP1, CASP8AP2, MXD1, and BTG2) and 3 genes in MTX plus anti-TNF nonresponders (CCL4, CD83, and BCL2A1) were identified for further study.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antirreumáticos/uso terapêutico , Artrite Reumatoide/genética , Metotrexato/uso terapêutico , Transcriptoma , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adulto , Idoso , Artrite Reumatoide/tratamento farmacológico , Quimioterapia Combinada , Feminino , Cadeias HLA-DRB1/genética , Humanos , Infliximab , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
20.
Brain Res ; 1367: 114-21, 2011 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-20974111

RESUMO

The aim of this study was to identify molecular pathways involved in audiogenic seizures in the epilepsy-prone Wistar Audiogenic Rat (WAR). For this, we used a suppression-subtractive hybridization (SSH) library from the hippocampus of WARs coupled to microarray comparative gene expression analysis, followed by Northern blot validation of individual genes. We discovered that the levels of the non-protein coding (npc) RNA BC1 were significantly reduced in the hippocampus of WARs submitted to repeated audiogenic seizures (audiogenic kindling) when compared to Wistar resistant rats and to both naive WARs and Wistars. By quantitative in situ hybridization, we verified lower levels of BC1 RNA in the GD-hilus and significant signal ratio reduction in the stratum radiatum and stratum pyramidale of hippocampal CA3 subfield of audiogenic kindled animals. Functional results recently obtained in a BC1⁻/⁻ mouse model and our current data are supportive of a potential disruption in signaling pathways, upstream of BC1, associated with the seizure susceptibility of WARs.


Assuntos
Regulação para Baixo/genética , Epilepsia Reflexa/patologia , Hipocampo/metabolismo , Excitação Neurológica/genética , RNA Citoplasmático Pequeno/genética , RNA não Traduzido/genética , Estimulação Acústica/efeitos adversos , Animais , Modelos Animais de Doenças , Eletroencefalografia , Epilepsia Reflexa/genética , Perfilação da Expressão Gênica/métodos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , RNA Citoplasmático Pequeno/metabolismo , Ratos , Ratos Wistar
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