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1.
Nature ; 594(7861): 117-123, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34012113

RESUMO

The human genome expresses thousands of natural antisense transcripts (NAT) that can regulate epigenetic state, transcription, RNA stability or translation of their overlapping genes1,2. Here we describe MAPT-AS1, a brain-enriched NAT that is conserved in primates and contains an embedded mammalian-wide interspersed repeat (MIR), which represses tau translation by competing for ribosomal RNA pairing with the MAPT mRNA internal ribosome entry site3. MAPT encodes tau, a neuronal intrinsically disordered protein (IDP) that stabilizes axonal microtubules. Hyperphosphorylated, aggregation-prone tau forms the hallmark inclusions of tauopathies4. Mutations in MAPT cause familial frontotemporal dementia, and common variations forming the MAPT H1 haplotype are a significant risk factor in many tauopathies5 and Parkinson's disease. Notably, expression of MAPT-AS1 or minimal essential sequences from MAPT-AS1 (including MIR) reduces-whereas silencing MAPT-AS1 expression increases-neuronal tau levels, and correlate with tau pathology in human brain. Moreover, we identified many additional NATs with embedded MIRs (MIR-NATs), which are overrepresented at coding genes linked to neurodegeneration and/or encoding IDPs, and confirmed MIR-NAT-mediated translational control of one such gene, PLCG1. These results demonstrate a key role for MAPT-AS1 in tauopathies and reveal a potentially broad contribution of MIR-NATs to the tightly controlled translation of IDPs6, with particular relevance for proteostasis in neurodegeneration.


Assuntos
Biossíntese de Proteínas/genética , Proteostase/genética , RNA Antissenso/genética , Tauopatias/genética , Tauopatias/metabolismo , Proteínas tau/genética , Proteínas tau/metabolismo , Idoso , Animais , Sítios de Ligação , Encéfalo/metabolismo , Encéfalo/patologia , Estudos de Casos e Controles , Diferenciação Celular , Progressão da Doença , Feminino , Humanos , Sítios Internos de Entrada Ribossomal/genética , Masculino , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Neurônios/metabolismo , Neurônios/patologia , Ribossomos/metabolismo , Proteínas tau/biossíntese
2.
Int J Mol Sci ; 25(11)2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38891761

RESUMO

Abiraterone acetate (AA) serves as a medication for managing persistent testosterone production in patients with metastatic castration-resistant prostate cancer (mCRPC). However, its efficacy varies among individuals; thus, the identification of biomarkers to predict and follow treatment response is required. In this pilot study, we explored the potential of circulating microRNAs (c-miRNAs) to stratify patients based on their responsiveness to AA. We conducted an analysis of plasma samples obtained from a cohort of 33 mCRPC patients before and after three, six, and nine months of AA treatment. Using miRNA RT-qPCR panels for candidate discovery and TaqMan RT-qPCR for validation, we identified promising miRNA signatures. Our investigation indicated that a signature based on miR-103a-3p and miR-378a-5p effectively discriminates between non-responder and responder patients, while also following the drug's efficacy over time. Additionally, through in silico analysis, we identified target genes and transcription factors of the two miRNAs, including PTEN and HOXB13, which are known to play roles in AA resistance in mCRPC. In summary, our study highlights two c-miRNAs as potential companion diagnostics of AA in mCRPC patients, offering novel insights for informed decision-making in the treatment of mCRPC.


Assuntos
Acetato de Abiraterona , Biomarcadores Tumorais , MicroRNAs , Neoplasias de Próstata Resistentes à Castração , Humanos , Masculino , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/sangue , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/patologia , Neoplasias de Próstata Resistentes à Castração/diagnóstico , Acetato de Abiraterona/uso terapêutico , Projetos Piloto , Idoso , MicroRNAs/sangue , MicroRNAs/genética , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Pessoa de Meia-Idade , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , PTEN Fosfo-Hidrolase/genética , MicroRNA Circulante/sangue , Metástase Neoplásica , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/sangue , Idoso de 80 Anos ou mais
3.
BMC Genomics ; 22(1): 237, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33823787

RESUMO

BACKGROUND: Colossoma macropomum (tambaqui) and Piaractus mesopotamicus (pacu) are good fish species for aquaculture. The tambacu, individuals originating from the induced hybridization of the female tambaqui with the male pacu, present rapid growth and robustness, characteristics which have made the tambacu a good choice for Brazilian fish farms. Here, we used small RNA sequencing to examine global miRNA expression in the genotypes pacu (PC), tambaqui (TQ), and hybrid tambacu (TC), (Juveniles, n = 5 per genotype), to better understand the relationship between tambacu and its parental species, and also to clarify the mechanisms involved in tambacu muscle growth and maintenance based on miRNAs expression. RESULTS: Regarding differentially expressed (DE) miRNAs between the three genotypes, we observed 8 upregulated and 7 downregulated miRNAs considering TC vs. PC; 14 miRNAs were upregulated and 10 were downregulated considering TC vs. TQ, and 15 miRNAs upregulated and 9 were downregulated considering PC vs. TQ. The majority of the miRNAs showed specific regulation for each genotype pair, and no miRNA were shared between the 3 genotype pairs, in both up- and down-regulated miRNAs. Considering only the miRNAs with validated target genes, we observed the miRNAs miR-144-3p, miR-138-5p, miR-206-3p, and miR-499-5p. GO enrichment analysis showed that the main target genes for these miRNAs were grouped in pathways related to oxygen homeostasis, blood vessel modulation, and oxidative metabolism. CONCLUSIONS: Our global miRNA analysis provided interesting DE miRNAs in the skeletal muscle of pacu, tambaqui, and the hybrid tambacu. In addition, in the hybrid tambacu, we identified some miRNAs controlling important molecular muscle markers that could be relevant for the farming maximization.


Assuntos
Caraciformes , MicroRNAs , Animais , Brasil , Caraciformes/genética , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , MicroRNAs/genética , Músculo Esquelético
4.
Anal Chem ; 91(9): 5874-5880, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30994325

RESUMO

Circulating microRNAs have been identified as potential biomarkers for early detection, prognosis, and prediction of several diseases. Their use in clinical diagnostics has been limited by the lack of suitable detection techniques. Most of the current technologies suffer from requiring complex protocols, not yet able to deliver robust and cost-effective assays in the field of clinical diagnostics. In this work, we report the development of a breakthrough platform for profiling circulating microRNAs. The platform comprises a novel silicon photomultiplier-based reader in conjunction with a chemical-based method for nucleic acid detection. Accurate microRNAs profiling without extraction, pre-amplification, or pre-labeling of the target is now achievable. We designed and synthesized a set of reagents that combined the chemical-based method with a chemiluminescent reaction. The signals generated were read out using a novel, compact silicon photomultiplier-based reader. The platform sensitivity was determined by measuring known concentrations of hsa-miR-21-5p spike-ins. The limit of detection was calculated as 4.7 pmol/L. The platform was also successfully used to directly detect hsa-miR-21-5p in eight non-small cell lung cancer plasma samples. Levels of plasma hsa-miR-21-5p expression were also measured via TaqMan RT-qPCR. The successful integration of the unique chemical-based method for nucleic acid detection with the novel silicon photomultiplier-based reader created an innovative product (ODG platform) with diagnostic utility, for the direct qualitative and quantitative analysis of microRNA biomarkers in biological fluids.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Pulmonar de Células não Pequenas/sangue , MicroRNA Circulante/sangue , Neoplasias Pulmonares/sangue , MicroRNAs/sangue , Reação em Cadeia da Polimerase em Tempo Real/métodos , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/genética , MicroRNA Circulante/genética , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , MicroRNAs/genética , Curva ROC
5.
Adv Exp Med Biol ; 889: 153-77, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26659001

RESUMO

Lung cancer is the leading cause of cancer mortality worldwide. microRNAs (miRNAs) have been established as players with a relevant role in lung cancer development, epithelial-mesenchymal transition and response to therapy. Additionally, in the last decade, miRNAs, measured in resected tumor samples or in fine-needle aspirate samples have emerged as compelling biomarkers for tumor diagnosis, prognosis, and prediction of response to treatment, due to the ease of their detection and in their extreme specificity. Moreover, miRNAs present in sputum, in plasma, in serum or in whole-blood have increasingly been explored in the last 5 years as less invasive biomarkers for the early detection of cancers.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , MicroRNAs/genética , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/tratamento farmacológico , MicroRNAs/sangue , Prognóstico , Escarro/metabolismo
6.
Molecules ; 19(5): 6891-910, 2014 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-24858274

RESUMO

Neurodegenerative disorders, such as Alzheimer's disease (AD), Parkinson's disease (PD) and frontotemporal dementias (FTD), are considered distinct entities, however, there is increasing evidence of an overlap from the clinical, pathological and genetic points of view. All neurodegenerative diseases are characterized by neuronal loss and death in specific areas of the brain, for example, hippocampus and cortex for AD, midbrain for PD, frontal and temporal lobes for FTD. Loss of neurons is a relatively late event in the progression of neurodegenerative diseases that is typically preceded by other events such as metabolic changes, synaptic dysfunction and loss, neurite retraction, and the appearance of other abnormalities, such as axonal transport defects. The brain's ability to compensate for these dysfunctions occurs over a long period of time and results in late clinical manifestation of symptoms, when successful pharmacological intervention is no longer feasible. Currently, diagnosis of AD, PD and different forms of dementia is based primarily on analysis of the patient's cognitive function. It is therefore important to find non-invasive diagnostic methods useful to detect neurodegenerative diseases during early, preferably asymptomatic stages, when a pharmacological intervention is still possible. Altered expression of microRNAs (miRNAs) in many disease states, including neurodegeneration, and increasing relevance of miRNAs in biofluids in different pathologies has prompted the study of their possible application as neurodegenerative diseases biomarkers in order to identify new therapeutic targets. Here, we review what is known about the role of miRNAs in the pathogenesis of neurodegeneration and the possibilities and challenges of using these small RNA molecules as a signature for neurodegenerative conditions.


Assuntos
Biomarcadores/metabolismo , MicroRNAs/metabolismo , Doenças Neurodegenerativas/genética , Doença de Alzheimer/genética , Biomarcadores/análise , Humanos , MicroRNAs/análise , Neoplasias/genética , Doenças Neurodegenerativas/diagnóstico , Doença de Parkinson/genética
7.
Mol Neurobiol ; 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39138758

RESUMO

Despite the efforts to identify fluid biomarkers to improve diagnosis of Frontotemporal dementia (FTD), only a few candidates have been described in recent years. In a previous study, we identified three circulating miRNAs (miR-92a-3p, miR-320a and miR-320b) differentially expressed in FTD patients with respect to healthy controls and/or Alzheimer's disease (AD) patients. Now, we investigated whether those changes could be due to miRNAs contained in neuron-derived extracellular vesicles (NDEVs). We also evaluated miRNAs content in total plasma EVs and in CSF samples. The analysis of plasma NDEVs carried out on 40 subjects including controls (n = 13), FTD (n = 13) and AD (n = 14) patients, showed that both miR-92a-3p and miR-320a levels were triplicated in the FTD group if compared with CT and AD patients. Increased levels of the same miRNAs were found also in CSF derived from FTD group compared to CTs. No differences were observed in expression levels of miR-320b among the three groups. Worthy of note, all miRNAs analysed were increased in an FTD cell model, MAPT IVS10 + 16 neurons. Our results suggest that miR-92a and miR-320a in NDEVs could be proposed as FTD biomarkers.

8.
BMC Cancer ; 13: 552, 2013 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-24256616

RESUMO

BACKGROUND: The tumor suppressor p53 is a sequence-specific transcription factor that regulates an extensive network of coding genes, long non-coding RNAs and microRNAs, that establish intricate gene regulatory circuits influencing many cellular responses beyond the prototypical control of cell cycle, apoptosis and DNA repair. METHODS: Using bioinformatic approaches, we identified an additional group of candidate microRNAs (miRs) under direct p53 transcriptional control. To validate p53 family-mediated responsiveness of the newly predicted target miRs we first evaluated the potential for wild type p53, p63ß and p73ß to transactivate from p53 response elements (REs) mapped in the miR promoters, using an established yeast-based assay. RESULTS: The REs found in miR-10b, -23b, -106a, -151a, -191, -198, -202, -221, -320, -1204, -1206 promoters were responsive to p53 and 8 of them were also responsive to p63ß or p73ß. The potential for germline p53 mutations to drive transactivation at selected miR-associated REs was also examined. Chromatin Immuno-Precipitation (ChIP) assays conducted in doxorubicin-treated MCF7 cells and HCT116 p53+/+ revealed moderate induction of p53 occupancy at the miR-202, -1204, -1206, -10b RE-containing sites, while weak occupancy was observed for the miR-23b-associated RE only in MCF7 cells. RT-qPCR analyses cells showed modest doxorubicin- and/or Nutlin-dependent induction of the levels of mature miR-10b, -23b, -151a in HCT116 p53+/+ and MCF7 cells. The long noncoding RNA PVT1 comprising miR-1204 and -1206 was weakly induced only in HCT116 p53+/+ cells, but the mature miRs were not detected. miR-202 expression was not influenced by p53-activating stimuli in our cell systems. CONCLUSIONS: Our study reveals additional miRs, particularly miR-10b and miR-151a, that could be directly regulated by the p53-family of transcription factors and contribute to the tuning of p53-induced responses.


Assuntos
Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Proteína Supressora de Tumor p53/fisiologia , Antibióticos Antineoplásicos/farmacologia , Sítios de Ligação , Cromatina , Biologia Computacional , Proteínas de Ligação a DNA/fisiologia , Doxorrubicina/farmacologia , Genes Reporter , Células HCT116 , Humanos , Luciferases de Vaga-Lume/biossíntese , Luciferases de Vaga-Lume/genética , Células MCF-7 , MicroRNAs/metabolismo , Proteínas Nucleares/fisiologia , Regiões Promotoras Genéticas , Ligação Proteica , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Elementos de Resposta , Saccharomyces cerevisiae , Fatores de Transcrição/fisiologia , Ativação Transcricional , Proteína Tumoral p73 , Proteínas Supressoras de Tumor/fisiologia
9.
RNA Biol ; 10(3): 360-6, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23466755

RESUMO

The life of an mRNA molecule begins with transcription and ultimately ends in degradation. In the course of its life, however, mRNA is examined, modified in various ways and transported before eventually being translated into proteins. All these processes are performed by proteins and non-coding RNAs whose complex interplay in the cell contributes to determining the proteome changes and the phenotype of cells. On May 23‒26, 2012, over 150 scientists from around the world convened in the sunny shores of Riva del Garda, Italy, for the workshop entitled: "mRNA fate: Life and Death of mRNA in the Cytoplasm." Sessions included mRNA trafficking, mRNA translational control, RNA metabolism and disease, RNA-protein structures and systems biology of RNA. This report highlights some of the prominent and recurring themes at the meeting and emerging arenas of future research.


Assuntos
Citoplasma/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Animais , Regulação da Expressão Gênica , Humanos , MicroRNAs/química , MicroRNAs/genética , MicroRNAs/metabolismo , Fenótipo , Biossíntese de Proteínas , Proteínas/química , Proteínas/metabolismo , Proteoma , Estabilidade de RNA , RNA Mensageiro/química
10.
Front Mol Neurosci ; 16: 1127163, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37324585

RESUMO

Background: Dementia is one of the most common diseases in elderly people and hundreds of thousand new cases per year of Alzheimer's disease (AD) are estimated. While the recent decade has seen significant advances in the development of novel biomarkers to identify dementias at their early stage, a great effort has been recently made to identify biomarkers able to improve differential diagnosis. However, only few potential candidates, mainly detectable in cerebrospinal fluid (CSF), have been described so far. Methods: We searched for miRNAs regulating MAPT translation. We employed a capture technology able to find the miRNAs directly bound to the MAPT transcript in cell lines. Afterwards, we evaluated the levels of these miRNAs in plasma samples from FTD (n = 42) and AD patients (n = 33) and relative healthy controls (HCs) (n = 42) by using qRT-PCR. Results: Firstly, we found all miRNAs that interact with the MAPT transcript. Ten miRNAs have been selected to verify their effect on Tau levels increasing or reducing miRNA levels by using cell transfections with plasmids expressing the miRNAs genes or LNA antagomiRs. Following the results obtained, miR-92a-3p, miR-320a and miR-320b were selected to analyse their levels in plasma samples of patients with FTD and AD respect to HCs. The analysis showed that the miR-92a-1-3p was under-expressed in both AD and FTD compared to HCs. Moreover, miR-320a was upregulated in FTD vs. AD patients, particularly in men when we stratified by sex. Respect to HC, the only difference is showed in men with AD who have reduced levels of this miRNA. Instead, miR-320b is up-regulated in both dementias, but only patients with FTD maintain this trend in both genders. Conclusions: Our results seem to identify miR-92a-3p and miR-320a as possible good biomarkers to discriminate AD from HC, while miR-320b to discriminate FTD from HC, particularly in males. Combining three miRNAs improves the accuracy only in females, particularly for differential diagnosis (FTD vs. AD) and to distinguish FTD from HC.

11.
Methods Mol Biol ; 2404: 207-218, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34694611

RESUMO

microRNA capture affinity technology (miR-CATCH) uses affinity capture biotinylated antisense oligonucleotides to co-purify a target transcript together with all its endogenously bound miRNAs. The miR-CATCH assay is performed to investigate miRNAs bound to a specific mRNA. This method allows to have a total vision of miRNAs bound not only to the 3'UTR but also to the 5'UTR and Coding Region of target messenger RNAs (mRNAs).


Assuntos
MicroRNAs/genética , Regiões 3' não Traduzidas , Oligonucleotídeos Antissenso/genética , RNA Mensageiro , Tecnologia
12.
Biol Open ; 11(10)2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-36239357

RESUMO

Since the formalization of the Central Dogma of molecular biology, the relevance of RNA in modulating the flow of information from DNA to proteins has been clear. More recently, the discovery of a vast set of non-coding transcripts involved in crucial aspects of cellular biology has renewed the enthusiasm of the RNA community. Moreover, the remarkable impact of RNA therapies in facing the COVID19 pandemics has bolstered interest in the translational opportunities provided by this incredible molecule. For all these reasons, the Italian Society of Biophysics and Molecular Biology (SIBBM) decided to dedicate its 17th yearly meeting, held in June 2022 in Rome, to the many fascinating aspects of RNA biology. More than thirty national and international speakers covered the properties, modes of action and applications of RNA, from its role in the control of development and cell differentiation to its involvement in disease. Here, we summarize the scientific content of the conference, highlighting the take-home message of each presentation, and we stress the directions the community is currently exploring to push forward our comprehension of the RNA World 3.0.


Assuntos
COVID-19 , RNA , Biofísica , Biotecnologia , Humanos , Biologia Molecular , RNA/genética
13.
Nucleic Acid Ther ; 31(3): 183-184, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34097476

RESUMO

The number of novel potential RNA-based antisense therapeutics is rapidly increasing. However, efficient delivery to target tissues is still the main factor that limits their translation into the clinic. Although many groups in academia and industry are working toward the development of methods to improve antisense delivery to overcome this limitation, there are very few coordinated efforts to learn from the experience of other investigators by sharing "negative" results. In the field of nucleic acid therapeutics, or any other type of therapeutics, the ultimate aim of most research projects is to develop novel or improved therapeutic strategies. It seems only logical that experiments are thought to yield a "negative result" if there is an absence of an improvement in some parameter related to potential therapeutic efficacy. These data often do not get published in scientific journals or presented at scientific meetings. However, positive and negative results obtained from scientifically sound experiments are equally valuable in facilitating progress in the field. They avoid unnecessary duplication of experiments and allow researchers to take approaches that did not yield the predicted result into account when designing new experiments.


Assuntos
Ácidos Nucleicos , RNA Antissenso , Resultados Negativos , Oligonucleotídeos Antissenso/genética , Oligonucleotídeos Antissenso/uso terapêutico , RNA Antissenso/genética
14.
EMBO Mol Med ; 13(4): e13243, 2021 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-33821570

RESUMO

Nucleic acid-based therapeutics that regulate gene expression have been developed towards clinical use at a steady pace for several decades, but in recent years the field has been accelerating. To date, there are 11 marketed products based on antisense oligonucleotides, aptamers and small interfering RNAs, and many others are in the pipeline for both academia and industry. A major technology trigger for this development has been progress in oligonucleotide chemistry to improve the drug properties and reduce cost of goods, but the main hurdle for the application to a wider range of disorders is delivery to target tissues. The adoption of delivery technologies, such as conjugates or nanoparticles, has been a game changer for many therapeutic indications, but many others are still awaiting their eureka moment. Here, we cover the variety of methods developed to deliver nucleic acid-based therapeutics across biological barriers and the model systems used to test them. We discuss important safety considerations and regulatory requirements for synthetic oligonucleotide chemistries and the hurdles for translating laboratory breakthroughs to the clinic. Recent advances in the delivery of nucleic acid-based therapeutics and in the development of model systems, as well as safety considerations and regulatory requirements for synthetic oligonucleotide chemistries are discussed in this review on oligonucleotide-based therapeutics.


Assuntos
Nanopartículas , Oligonucleotídeos , Expressão Gênica , Oligonucleotídeos Antissenso , RNA Interferente Pequeno
15.
Neurobiol Aging ; 84: 240.e1-240.e12, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-30826067

RESUMO

The purpose of this study was to develop an easy and minimally invasive assay to detect a plasma miRNA profile in frontotemporal dementia (FTD) patients, with the final aim of discriminating between FTD patients and healthy controls (HCs). After a global miRNA profiling, significant downregulation of miR-663a, miR-502-3p, and miR-206 (p = 0.0001, p = 0.0002, and p = 0.02 respectively) in FTD patients was confirmed when compared with HCs in a larger case-control sample. Moreover, miR-663a and miR-502-3p showed significant differences in both genders, whereas miR-206, only in male subjects. To obtain a discriminating measure between FTD patients and HCs, we calculated a combined score of the 3 miRNAs by applying a Bayesian approach and obtaining a classifier with an accuracy of 84.4%. Moreover, for men, combined miRNA levels showed an excellent sensitivity (100%) and a good specificity (87.5%) in distinguishing FTD patients from HCs. All these findings open new hypotheses in the pathophysiology and new perspectives in the diagnosis of a complex pathology as FTD.


Assuntos
Demência Frontotemporal/genética , Envelhecimento Saudável , MicroRNAs/sangue , Demência Frontotemporal/sangue , Humanos
16.
J Neurosci Res ; 86(11): 2488-98, 2008 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-18438938

RESUMO

In amyloid-beta (Abeta)-stimulated microglial cells, blockade of chloride intracellular ion channel 1 (CLIC1) reverts the increase in tumor necrosis factor-alpha and nitric oxide (NO) production and results in neuroprotection of cocultured neurons. This effect could be of therapeutic efficacy in Alzheimer's disease (AD), where microglial activation may contribute to neurodegeneration, but it could reduce Abeta phagocytosis, which could facilitate amyloid plaque removal. Here, we analyzed the CLIC1 blockade effect on Abeta-stimulated mononuclear phagocytosis. In the microglial cell line BV-2, Abeta25-35 treatment enhanced fluorescent bead phagocytosis, which persisted also in the presence of IAA-94, a CLIC1 channel blocker. The same result was obtained in rat primary microglia and in BV2 cells, where CLIC1 expression had been knocked down with a plasmid producing small interfering RNAs. To address specifically the issue of Abeta phagocytosis, we treated BV-2 cells with biotinylated Abeta1-42 and measured intracellular amyloid by morphometric analysis. IAA-94-treated cells showed an increased Abeta phagocytosis after 24 hr and efficient degradation of ingested material after 72 hr. In addition, we tested Abeta1-42 phagocytosis in adult rat peritoneal macrophages. Also, these cells actively phagocytosed Abeta1-42 in the presence of IAA-94. However, the increased expression of inducible NO synthase (iNOS), stimulated by Abeta, was reverted by IAA-94. In parallel, a decrease in NO release was detected. These results suggest that blockade of CLIC1 stimulates Abeta phagocytosis in mononuclear phagocytes while inhibiting the induction of iNOS and further point to CLIC1 as a possible therapeutic target in AD.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Canais de Cloreto/metabolismo , Microglia/metabolismo , Fagocitose/fisiologia , Animais , Células Cultivadas , Diuréticos/farmacologia , Citometria de Fluxo , Glicolatos/farmacologia , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Macrófagos Peritoneais/metabolismo , Camundongos , Microscopia Confocal , Óxido Nítrico Sintase Tipo II/biossíntese , Óxido Nítrico Sintase Tipo II/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Interferência de RNA , Ratos
17.
Sci Rep ; 8(1): 10476, 2018 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-29992994

RESUMO

The dysbiosis of the oral microbiome is associated with both localized and systemic diseases. Modulating the resident microbial communities by the dietary consumption of probiotics has become an appealing means to promote host health by either restoring host-microbe balance or preventing dysbiosis. Most probiotics strategies target the intestinal microbiome, but little is known about their impact on the oral microbiome. We analyzed here the saliva microbiome from 21 volunteers, longitudinally collected before, during, and after consumption of a commercial probiotic and a standard yoghurt using 16S amplicon sequencing. The alpha diversity of the saliva microbiome had a statistically significant increase (P-value = 0.0011) in one of the groups that consumed the probiotic. The overall structure of the microbiome was however not significantly impacted by the probiotic, although oligotyping analysis revealed that both Streptococci and Lactobacilli present in the probiotic product persisted in the saliva microbiome. In contrast, non-probiotic yoghurt consumption had a lesser impact on the overall diversity and Lactobacillus and Streptococcus persistence. Our results suggest that consumption of commercial probiotics in healthy subjects increase the overall diversity of the oral cavity microbiome in the short term, but such dietary interventions are not able to substantially modify the structure of the microbiome.


Assuntos
Microbiota/efeitos dos fármacos , Boca/microbiologia , Probióticos/farmacologia , Saliva/microbiologia , Biodiversidade , Feminino , Voluntários Saudáveis , Humanos , Estudos Longitudinais , Masculino , Probióticos/administração & dosagem , RNA Ribossômico 16S/genética , Fatores de Tempo , Adulto Jovem
18.
J Alzheimers Dis ; 65(2): 455-464, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30056425

RESUMO

Given the heterogeneous nature of frontotemporal dementia (FTD), sensitive biomarkers are greatly needed for the accurate diagnosis of this neurodegenerative disorder. Circulating miRNAs have been reported as promising biomarkers for neurodegenerative disorders and processes affecting the central nervous system, especially in aging. The objective of the study was to evaluate if some circulating miRNAs linked with apoptosis (miR-29b-3p, miR-34a-5p, miR-16-5p, miR-17-5p, miR-107, miR-19b-3p, let-7b-5p, miR-26b-5p, and 127-3p) were able to distinguish between FTD patients and healthy controls. For this study, we enrolled 127 subjects, including 54 patients with FTD, 20 patients with Alzheimer's disease (AD), and 53 healthy controls. The qRT-PCR analysis showed a downregulation of miR-127-3p in FTD compared to controls, while the levels of other miRNAs remained unchanged. Then, miR-127-3p expression was also analyzed in AD patients, finding a different expression between two patient groups. A receiver operating characteristic curve was then created for miR-127-3p to discriminate FTD versus AD (AUC: 0.8986), and versus healthy controls (AUC: 0.8057). In conclusion, miR-127-3p could help to diagnose FTD and to distinguish it from AD.


Assuntos
MicroRNA Circulante/sangue , Demência Frontotemporal/sangue , MicroRNAs/sangue , Idoso , Doença de Alzheimer/sangue , Biomarcadores/sangue , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Sensibilidade e Especificidade
19.
Front Cell Dev Biol ; 5: 86, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29018797

RESUMO

Since their discovery and the advent of RNA interference, microRNAs have drawn enormous attention because of their ubiquitous involvement in cellular pathways from life to death, from metabolism to communication. It is also widely accepted that they possess an undeniable role in cancer both as tumor suppressors and tumor promoters modulating cell proliferation and migration, epithelial-mesenchymal transition and tumor cell invasion and metastasis. Moreover, microRNAs can even affect the tumor surrounding environment influencing angiogenesis and immune system activation and recruitment. The tight association of microRNAs with several cancer-related processes makes them undoubtedly connected to the effect of specific cancer drugs inducing either resistance or sensitization. In this context, personalized medicine through microRNAs arose recently with the discovery of single nucleotide polymorphisms in the target binding sites, in the sequence of the microRNA itself or in microRNA biogenesis related genes, increasing risk, susceptibility and progression of multiple types of cancer in different sets of the population. The depicted scenario implies that the overall variation displayed by these small non-coding RNAs have an impact on patient-specific pharmacokinetics and pharmacodynamics of cancer drugs, pushing on a rising need of personalized treatment. Indeed, microRNAs from either tissues or liquid biopsies are also extensively studied as valuable biomarkers for disease early recognition, progression and prognosis. Despite microRNAs being intensively studied in recent years, a comprehensive review describing these topics all in one is missing. Here we report an up-to-date and critical summary of microRNAs as tools for better understanding personalized cancer biogenesis, evolution, diagnosis and treatment.

20.
EMBO Mol Med ; 9(5): 545-557, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28289078

RESUMO

The use of splice-switching antisense therapy is highly promising, with a wealth of pre-clinical data and numerous clinical trials ongoing. Nevertheless, its potential to treat a variety of disorders has yet to be realized. The main obstacle impeding the clinical translation of this approach is the relatively poor delivery of antisense oligonucleotides to target tissues after systemic delivery. We are a group of researchers closely involved in the development of these therapies and would like to communicate our discussions concerning the validity of standard methodologies currently used in their pre-clinical development, the gaps in current knowledge and the pertinent challenges facing the field. We therefore make recommendations in order to focus future research efforts and facilitate a wider application of therapeutic antisense oligonucleotides.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Terapia Genética/métodos , Oligonucleotídeos Antissenso/administração & dosagem , Splicing de RNA , Animais , Vias de Administração de Medicamentos , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Oligonucleotídeos Antissenso/farmacocinética , Oligonucleotídeos Antissenso/uso terapêutico , Oligonucleotídeos Antissenso/toxicidade , Splicing de RNA/efeitos dos fármacos
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