RESUMO
Artificial microRNAs (amiRNAs) are highly specific, 21-nucleotide (nt) small RNAs designed to silence target transcripts. In plants, their application as biotechnological tools for functional genomics or crop improvement is limited by the need of transgenically expressing long primary miRNA (pri-miRNA) precursors to produce the amiRNAs in vivo. Here, we analyzed the minimal structural and sequence requirements for producing effective amiRNAs from the widely used, 521-nt long AtMIR390a pri-miRNA from Arabidopsis thaliana. We functionally screened in Nicotiana benthamiana a large collection of constructs transiently expressing amiRNAs against endogenous genes and from artificially shortened MIR390-based precursors and concluded that highly effective and accurately processed amiRNAs can be produced from a chimeric precursor of only 89 nt. This minimal precursor was further validated in A. thaliana transgenic plants expressing amiRNAs against endogenous genes. Remarkably, minimal but not full-length precursors produce authentic amiRNAs and induce widespread gene silencing in N. benthamiana when expressed from an RNA virus, which can be applied into leaves by spraying infectious crude extracts. Our results reveal that the length of amiRNA precursors can be shortened without affecting silencing efficacy, and that viral vectors including minimal amiRNA precursors can be applied in a transgene-free manner to induce whole-plant gene silencing.
Assuntos
Arabidopsis , MicroRNAs , MicroRNAs/genética , Inativação Gênica , Plantas Geneticamente Modificadas/genética , Nicotiana/genética , Transgenes , Arabidopsis/genéticaRESUMO
Skin represents the main barrier against the external environment, but also plays a role in human relations, as one of the prime determinants of beauty, resulting in a high consumer demand for skincare-related pharmaceutical products. Given the importance of skin aging in both medical and social spheres, the present research aims to characterize microscopic changes in human skin composition due to intrinsic aging (as opposed to aging influenced by external factors) via histological analysis of a photoprotected body region. Samples from 25 autopsies were taken from the periumbilical area and classified into four age groups: group 1 (0-12 years), group 2 (13-25 years), group 3 (26-54 years), and group 4 (≥ 55 years). Different traditional histological (hematoxylin-eosin, Masson's trichrome, orcein, toluidine, Alcian blue, and Feulgen reaction) and immunohistochemical (CK20, CD1a, Ki67, and CD31) stains were performed. A total of 1879 images photographed with a Leica DM3000 optical microscope were morphometrically analyzed using Image ProPlus 7.0 for further statistical analysis with GraphPad 9.0. Our results showed a reduction in epidermis thickness, interdigitation and mitotic indexes, while melanocyte count was raised. Papillary but not reticular dermis showed increased thickness with aging. Specifically, in the papillary layer mast cells and glycosaminoglycans were expanded, whereas the reticular dermis displayed a diminution in glycosaminoglycans and elastic fibers. Moreover, total cellularity and vascularization of both dermises were diminished with aging. This morphometric analysis of photoprotected areas reveals that intrinsic aging significantly influences human skin composition. This study paves the way for further research into the molecular basis underpinning these alterations, and into potential antiaging strategies.
Assuntos
Envelhecimento , Pele , Humanos , Pessoa de Meia-Idade , Adulto , Adolescente , Adulto Jovem , Pele/metabolismo , Pele/química , Feminino , Masculino , Criança , Envelhecimento/patologia , Lactente , Pré-Escolar , Recém-Nascido , Envelhecimento da Pele , Idoso , Imuno-HistoquímicaRESUMO
Following myocardial infarction (MI), adverse remodeling depends on the proper formation of fibrotic scars, composed of type I and III collagen. Our objective was to pinpoint the participation of previously unreported collagens in post-infarction cardiac fibrosis. Gene (qRT-PCR) and protein (immunohistochemistry followed by morphometric analysis) expression of fibrillar (types II and XI) and non-fibrillar (types VIII and XII) collagens were determined in RNA-sequencing data from 92 mice undergoing myocardial ischemia; mice submitted to permanent (non-reperfused MI, n = 8) or transient (reperfused MI, n = 8) coronary occlusion; and eight autopsies from chronic MI patients. In the RNA-sequencing analysis of mice undergoing myocardial ischemia, increased transcriptomic expression of collagen types II, VIII, XI, and XII was reported within the first week, a tendency that persisted 21 days afterwards. In reperfused and non-reperfused experimental MI models, their gene expression was heightened 21 days post-MI induction and positively correlated with infarct size. In chronic MI patients, immunohistochemistry analysis demonstrated their presence in fibrotic scars. Functional analysis indicated that these subunits probably confer tensile strength and ensure the cohesion of interstitial components. Our data reveal that novel collagens are present in the infarcted myocardium. These data could lay the groundwork for unraveling post-MI fibrotic scar composition, which could ultimately influence patient survivorship.
Assuntos
Cicatriz , Fibrose , Infarto do Miocárdio , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Infarto do Miocárdio/genética , Animais , Camundongos , Humanos , Cicatriz/metabolismo , Cicatriz/patologia , Cicatriz/genética , Masculino , Miocárdio/metabolismo , Miocárdio/patologia , Colágenos Fibrilares/metabolismo , Colágenos Fibrilares/genética , Feminino , Modelos Animais de Doenças , Colágeno/metabolismo , Pessoa de Meia-Idade , Camundongos Endogâmicos C57BLRESUMO
BACKGROUND: Grieving is an adaptive process in the face of the death of somebody close. Children grieve the loss of a family member or friend and need support from their caregivers and the professionals who care for them during this process. Failure to talk to children about the death of a family member or friend can lead to prolonged grief. Children's story books are one of the resources available for providing this type of support. OBJECTIVE: To provide the nursing professional with information on story books aimed at children from 7 to 11 years of age as a tool to help them understand and cope with grief. DESIGN: A systematic integrative review was conducted. METHODS: A search was performed in the ISBN database of the Ministry of Culture and the University Libraries Network. Data extraction was performed by two coders using a protocol registered in PROSPERO. RESULTS: Fifty-six books met the inclusion criteria. Twenty-five percent of the deceased characters were grandparents and 30.4% died due to illness. The most frequent emotion was sadness, (43.3%) and the most repeated coping strategy was remembering the deceased person, (28.7%). The grieving process was depicted in 32.1% of the selected stories. CONCLUSION: The children's books reviewed support understanding and coping with grief. However, some limitations were detected, and therefore it is advisable to accompany the child while reading these books to discuss aspects that have not been addressed.
Assuntos
Emoções , Pesar , Criança , Humanos , Família , Adaptação Psicológica , LivrosRESUMO
Endothelial cells (ECs) are a key target for cardioprotection due to their role in preserving cardiac microvasculature and homeostasis after myocardial infarction (MI). Our goal is to identify the genes involved in post-MI EC proliferation, EC apoptosis, and angiogenesis regulation via RNA-sequencing transcriptomic datasets. Using eight studies from the Gene Expression Omnibus, RNA-sequencing data from 92 mice submitted to different times of coronary ischemia or sham were chosen. Functional enrichment analysis was performed based on gene ontology biological processes (BPs). Apoptosis-related BPs are activated up to day 3 after ischemia onset, whereas endothelial proliferation occurs from day 3 onwards, including an overrepresentation of up to 37 genes. Endothelial apoptosis post-MI is triggered via both the extrinsic and intrinsic signaling pathways, as reflected by the overrepresentation of 13 and 2 specific genes, respectively. BPs implicated in new vessel formation are upregulated soon after ischemia onset, whilst the mechanisms aiming at angiogenesis repression can be detected at day 3. Overall, 51 pro-angiogenic and 29 anti-angiogenic factors displayed altered transcriptomic expression post-MI. This is the first study using RNA sequencing datasets to evaluate the genes participating in post-MI endothelium physiology and angiogenesis regulation. These novel data could lay the groundwork to advance understanding of the implication of ECs after MI.
Assuntos
Células Endoteliais , Infarto do Miocárdio , Camundongos , Animais , Células Endoteliais/metabolismo , Neovascularização Fisiológica/genética , Infarto do Miocárdio/metabolismo , RNA/metabolismo , Análise de Sequência de RNARESUMO
The lysyl oxidase (LOX) family of enzymes catalyze the oxidative deamination of lysine and hydroxylysine residues in collagen and elastin in the initiation step of the formation of covalent cross-linkages, an essential process for extracellular matrix (ECM) maturation. Elevated LOX expression levels leading to increased LOX activity is associated with diverse pathologies including fibrosis, cancer, and cardiovascular diseases. Different protocols have been so far established to detect and quantify LOX activity from tissue samples and cultured cells, all of them showing advantages and drawbacks. This review article presents a critical overview of the main features of currently available methods as well as introduces some recent technologies called to revolutionize our approach to LOX catalysis.
Assuntos
Ensaios Enzimáticos/métodos , Proteína-Lisina 6-Oxidase/metabolismo , Animais , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Doenças Cardiovasculares/enzimologia , Ensaios Enzimáticos/instrumentação , Humanos , Neoplasias/enzimologia , Imagem Óptica/instrumentação , Imagem Óptica/métodos , Proteína-Lisina 6-Oxidase/análiseRESUMO
Members of the lysyl oxidase (LOX) family catalyze the oxidative deamination of lysine and hydroxylysine residues in collagen and elastin in the initiation step of the formation of covalent cross-links, an essential process for connective tissue maturation. Proteolysis has emerged as an important level of regulation of LOX enzymes with the cleavage of the LOX isoform by metalloproteinases of the BMP1 (bone morphogenetic protein 1) and ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) families as a model example. Lysyl oxidase-like 1 (LOXL1), an isoform associated with pelvic organ prolapse and pseudoexfoliation (PEX) glaucoma, has also been reported to be proteolytically processed by these proteases. However, precise molecular information on these proteolytic events is not available. In this study, using genetic cellular models, along with proteomic analyses, we describe that LOXL1 is processed by BMP1 and ADAMTS14 and identify the processing sites in the LOXL1 protein sequence. Our data show that BMP1 cleaves LOXL1 in a unique location within the pro-peptide region, whereas ADAMTS14 processes LOXL1 in at least three different sites located within the pro-peptide and in the first residues of the catalytic domain. Taken together, these results suggest a complex regulation of LOXL1 function by BMP1- and ADAMTS14-mediated proteolysis where LOXL1 enzymes retaining variable fragments of N-terminal region may display different capabilities.
Assuntos
Síndrome de Exfoliação , Proteína-Lisina 6-Oxidase , Proteínas ADAMTS/metabolismo , Aminoácido Oxirredutases/genética , Aminoácido Oxirredutases/metabolismo , Proteína Morfogenética Óssea 1/genética , Proteína Morfogenética Óssea 1/metabolismo , Síndrome de Exfoliação/genética , Humanos , Peptídeo Hidrolases/metabolismo , Proteína-Lisina 6-Oxidase/metabolismo , Proteólise , ProteômicaRESUMO
Collagens are extracellular matrix (ECM) proteins that support the structural and biomechanical integrity of many tissues. Procollagen-lysine, 2-oxoglutarate 5-dioxygenase 2 (PLOD2) encodes the only lysyl hydroxylase (LH) isoform that specifically hydroxylates lysine residues in collagen telopeptides, a post-translational modification required for the formation of stabilized cross-links. PLOD2 expression is induced by hypoxia and transforming growth factor-ß1 (TGF-ß1), well-known stimuli for the formation of a fibrotic ECM, which can lead to pathological fibrosis underlying several diseases. Here, using human and murine fibroblasts, we studied the molecular determinants underlying hypoxia- and TGF-ß1-induced PLOD2 expression and its impact on collagen biosynthesis. Deletion mapping and mutagenesis analysis identified specific binding sites for hypoxia-inducible factors (HIF) and TGF-ß1-activated SMAD proteins on the human PLOD2 gene promoter that were required for these stimuli to induce PLOD2 expression. Interestingly, our experiments also revealed that HIF signaling plays a preponderant role in the SMAD pathway, as intact HIF sites were absolutely required for TGF-ß1 to exert its effect on SMAD-binding sites. We also found that silencing PLOD2 expression did not alter soluble collagen accumulation in the extracellular medium, but it effectively abolished the deposition into the insoluble collagen matrix. Taken together, our findings reveal the existence of a hierarchical relationship between the HIF and SMAD signaling pathways for hypoxia- and TGF-ß1-mediated regulation of PLOD2 expression, a key event in the deposition of collagen into the ECM.
Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fator 1 Induzível por Hipóxia/metabolismo , Oxigênio/metabolismo , Pró-Colágeno-Lisina 2-Oxoglutarato 5-Dioxigenase/genética , Proteínas Smad/metabolismo , Células 3T3 , Animais , Hipóxia Celular , Linhagem Celular Tumoral , Matriz Extracelular/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Camundongos , Pró-Colágeno-Lisina 2-Oxoglutarato 5-Dioxigenase/metabolismo , Regiões Promotoras Genéticas , Fator de Crescimento Transformador beta1/farmacologiaRESUMO
Collagens are the main structural component of the extracellular matrix and provide biomechanical properties to connective tissues. A critical step in collagen fibril formation is the proteolytic removal of N- and C-terminal propeptides from procollagens by metalloproteinases of the ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) and BMP1 (bone morphogenetic protein 1)/Tolloid-like families, respectively. BMP1 also cleaves and activates the lysyl oxidase (LOX) precursor, the enzyme catalyzing the initial step in the formation of covalent collagen cross-links, an essential process for fibril stabilization. In this study, using murine skin fibroblasts and HEK293 cells, along with immunoprecipitation, LOX enzymatic activity, solid-phase binding assays, and proteomics analyses, we report that the LOX precursor is proteolytically processed by the procollagen N-proteinases ADAMTS2 and ADAMTS14 between Asp-218 and Tyr-219, 50 amino acids downstream of the BMP1 cleavage site. We noted that the LOX sequence between the BMP1- and ADAMTS-processing sites contains several conserved tyrosine residues, of which some are post-translationally modified by tyrosine O-sulfation and contribute to binding to collagen. Taken together, these findings unravel an additional level of regulation in the formation of collagen fibrils. They point to a mechanism that controls the binding of LOX to collagen and is based on differential BMP1- and ADAMTS2/14-mediated cleavage of a tyrosine-sulfated domain.
Assuntos
Proteínas ADAMTS/metabolismo , Proteína Morfogenética Óssea 1/metabolismo , Colágeno/metabolismo , Proteína-Lisina 6-Oxidase/metabolismo , Tirosina/análogos & derivados , Animais , Sítios de Ligação , Bovinos , Células Cultivadas , Células HEK293 , Humanos , Camundongos , Ligação Proteica , Processamento de Proteína Pós-Traducional , Proteína-Lisina 6-Oxidase/química , Proteólise , Tirosina/metabolismoRESUMO
Tobacco smoking is the main environmental risk factor for chronic obstructive pulmonary disease (COPD), but not all smokers develop the disease. A population of lung-resident mesenchymal stem cells (LR-MSCs) exist in healthy lungs, but how tobacco smoking affects them and their role in COPD have not been assessed yet. Using a sphere-based culture technique, we isolated LR-MSCs from lung tissue obtained from nonsmokers and current and former smokers with and without COPD (n = 53). The cells were characterized by flow cytometry and Affymetrix arrays. Their immunomodulatory capacity was assessed in vitro using cocultures with T cells and after preincubation with 2.5% and 5% cigarette smoke extract. We were able to isolate LR-MSCs expressing similar phenotypic markers in all of the study groups. LR-MSCs from current smokers with COPD expressed different levels of CX3CL1 and CCL5 cytokines, and were unable to modulate CD8+ T-cell proliferation. Preincubation of LR-MSCs with cigarette smoke extract reduced their immunomodulatory capacity. In conclusion, 1) LR-MSCs can be isolated in similar amounts from never-smokers and smokers with and without COPD; 2) their immunomodulatory capacity is impaired in current smokers with COPD, but not in those with normal lung function; and 3) this is reversible after smoking cessation and is reproducible in vitro.
Assuntos
Células-Tronco Mesenquimais/efeitos dos fármacos , Doença Pulmonar Obstrutiva Crônica/imunologia , Fumaça/efeitos adversos , Fumar/efeitos adversos , Feminino , Humanos , Pulmão/imunologia , Pulmão/fisiopatologia , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Masculino , Células-Tronco Mesenquimais/imunologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologiaRESUMO
BACKGROUND: Chronic Obstructive Pulmonary Disease (COPD) is associated with an abnormal pulmonary and systemic immune response to tobacco smoking. Yet, how do immune cells relate within and between these two biological compartments, how the pulmonary infiltrate influences the lung transcriptome, and what is the role of active smoking vs. presence of disease is unclear. METHODS: To investigate these questions, we simultaneously collected lung tissue and blood from 65 individuals stratified by smoking habit and presence of the disease. The immune cell composition of both tissues was assessed by flow cytometry, whole lung transcriptome was determined with Affymetrix arrays, and we used Weighted Gene Co-expression Network Analysis (WGCNA) to integrate results. RESULTS: Main results showed that: (1) current smoking and the presence of COPD were both independently associated with a reduction in the proportion of lung T cells and an increase of macrophages, specifically those expressing CD80 + CD163+; (2) changes in the proportion of infiltrating macrophages, smoking status or the level of airflow limitation were associated to different WGCNA modules, which were enriched in iron ion transport, extracellular matrix and cilium organization gene ontologies; and, (3) circulating white blood cells counts were correlated with lung macrophages and T cells. CONCLUSIONS: Mild-moderated COPD lung immune infiltrate is associated with the active smoking status and presence of disease; is associated with changes in whole lung tissue transcriptome and marginally reflected in blood.
Assuntos
Imunidade Celular/fisiologia , Pulmão/imunologia , Doença Pulmonar Obstrutiva Crônica/sangue , Doença Pulmonar Obstrutiva Crônica/imunologia , Transcriptoma/fisiologia , Idoso , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Feminino , Humanos , Pulmão/metabolismo , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Linfócitos T/imunologia , Linfócitos T/metabolismoAssuntos
Metilação de DNA , Volume Expiratório Forçado/genética , Volume Expiratório Forçado/fisiologia , Pulmão/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/genética , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Fumar/genética , Idoso , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Fumar/fisiopatologiaRESUMO
INTRODUCTION AND OBJECTIVES: Clinical and experimental studies have shown that, in patients with reperfused ST-segment elevation myocardial infarction (STEMI), abnormalities in the endothelial monolayer are initiated during ischemia but rapidly intensify upon restoration of blood perfusion to the ischemic area. We aimed to evaluate the effect of serum isolated after revascularization from STEMI patients on the degree of endothelial permeability in vitro, by promoting endothelial cell apoptosis and necrosis in vitro. We also investigated the association between the percentage of serum-induced endothelial cell apoptosis or necrosis in vitro and the extent of cardiovascular magnetic resonance (CMR)-derived parameters of reperfusion injury (edema, hemorrhage, and microvascular obstruction). METHODS: Human coronary artery endothelial cells were incubated with serum isolated 24hours after revascularization from 43 STEMI patients who underwent CMR and 14 control participants. We assessed the effect of STEMI serum on activation of apoptosis and necrosis, as well as on the permeability and structure of the endothelial monolayer. RESULTS: Serum from STEMI patients increased apoptosis (P <.01) and necrosis (P <.05) in human coronary artery endothelial cells and caused increased permeability of the endothelial monolayer in vitro (P <.01), due to enlarged intercellular spaces (P <.05 vs control in all cases). Higher serum-induced necrosis was associated with greater endothelial permeability in vitro (P <.05) and with more extensive CMR-derived indices of reperfusion injury and infarct size. CONCLUSIONS: Postreperfusion serum activates necrosis and apoptosis in endothelial cells and increases the degree of endothelial permeability in vitro. The more potent the necrosis-triggering effect of serum, the more deleterious the consequences in terms of the resulting cardiac structure.
Assuntos
Intervenção Coronária Percutânea , Traumatismo por Reperfusão , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Infarto do Miocárdio com Supradesnível do Segmento ST/etiologia , Células Endoteliais , Imageamento por Ressonância Magnética/métodos , Necrose/etiologia , Traumatismo por Reperfusão/etiologia , Intervenção Coronária Percutânea/efeitos adversos , Resultado do TratamentoRESUMO
We aimed to assess the correlation of cardiovascular magnetic resonance (CMR)-derived epicardial adipose tissue (EAT) with infarct size (IS) and residual systolic function in ST-segment elevation myocardial infarction (STEMI). We enrolled patients discharged for a first anterior reperfused STEMI submitted to undergo CMR. EAT, left ventricular (LV) ejection fraction (LVEF), and IS were quantified at the 1-week (n = 221) and at 6-month CMR (n = 167). At 1-week CMR, mean EAT was 31 ± 13 mL/m2. Patients with high EAT volume (n = 72) showed larger 1-week IS. After adjustment, EAT extent was independently related to 1-week IS. In patients with large IS at 1 week (>30% of LV mass, n = 88), those with high EAT showed more preserved 6-month LVEF. This association persisted after adjustment and in a 1:1 propensity score-matched patient subset. Overall, EAT decreased at 6 months. In patients with large IS, a greater reduction of EAT was associated with more preserved 6-month LVEF. In STEMI, a higher presence of EAT was associated with a larger IS. Nevertheless, in patients with large infarctions, high EAT and greater subsequent EAT reduction were linked to more preserved LVEF in the chronic phase. This dual and paradoxical effect of EAT fuels the need for further research in this field.
RESUMO
Transcriptional activity of the hypoxia inducible factor (HIF) relies on the formation of a heterodimer composed of an oxygen-regulated α-subunit and a stably expressed ß-subunit. Heterodimeric HIF activates expression by binding to RCGTG motifs within promoters of hypoxia-activated genes. Some hypoxia targets also possess an adjacent HIF ancillary sequence (HAS) reported to increase transcription but whose function remains obscure. Here, we investigate the contribution of the HAS element to the hypoxia response and its mechanism of action, using the HAS-containing prolyl 4-hydroxylase subunit α1 (P4HA1) as a gene model in NIH/3T3 mouse embryonic fibroblasts and HEK293 human embryonic kidney cells. Our HIF overexpression experiments demonstrate that the HAS motif is essential for full induction by hypoxia and that the presence of the tandem HAS/HIF, as opposed to HIF-only sequences, provides HIF proteins with the capacity to form complexes of stoichiometry beyond the classical heterodimer, likely tetramers, to cooperatively potentiate hypoxia-induced transcription. We also provide evidence of the crucial role played by the Fα helix of the PAS-B domain of the HIF1ß subunit to support the interaction between heterodimers. Functional analysis showed that human genes containing the HAS/HIF motifs are better responders to hypoxia, and their promoters are enriched for specific transcription factor binding sites. Gene ontology enrichment revealed a predominance of HAS/HIF in genes primarily related to tissue formation and development. Our findings add an extra level of regulation of the hypoxia/HIF signaling through multimerization of HIF proteins on regulatory elements containing the HAS/HIF motifs.
Assuntos
Proteínas de Ligação a DNA , Fatores de Transcrição , Animais , Humanos , Camundongos , Fatores de Transcrição/metabolismo , Proteínas de Ligação a DNA/metabolismo , Células HEK293 , RNA Mensageiro/metabolismo , Fibroblastos/metabolismo , HipóxiaRESUMO
BACKGROUND: Extracellular matrix (ECM) suffers substantial alterations after myocardial infarction (MI), including the invasion of leukocyte subtypes. Despite a complete reopening at epicardial level, hypoperfusion within the infarcted myocardium, known as microvascular obstruction (MVO), occurs and exerts a negative impact on ventricular remodeling. In this study, ECM composition at MVO regions was described using a morphometric analysis. METHODS: MI was induced in female swine (n = 10) by transitory 90-minute coronary occlusion followed by seven days of reperfusion. Prior to euthanasia, intracoronary thioflavin-S was infused. Within the infarcted myocardium, regions displaying MVO (thioflavin-S-) or no MVO (thioflavin-S+) were isolated and stained to morphometrically compare ECM composition. RESULTS: As reflected by cell invasion through ECM, areas with MVO displayed an enlarged presence of neutrophils and lymphocytes, whilst no differences in the amount of macrophages and myofibroblasts were detected compared to infarcted myocardium without MVO. Indeed, those regions with macroscopic MVO showed lower capillary density than areas without MVO. Lastly, a significant reduction in the extension of total collagen, type I, but not type III, collagen, laminin, and fibronectin together with an augmentation of polysaccharides were noted in areas showing MVO compared to those without microvascular injury. CONCLUSIONS: ECM composition in infarcted regions with MVO isolated from female swine displays a higher presence of inflammatory infiltrate and polysaccharides as well as reduced number of microvessels and collagen content compared to those areas without microvascular hypoperfusion. These characteristics might underlie the development of adverse ventricular remodeling in MI patients with extensive MVO.
Assuntos
Infarto do Miocárdio , Remodelação Ventricular , Humanos , Feminino , Suínos , Animais , Matriz Extracelular , Colágeno , PolissacarídeosRESUMO
Toll-like receptor 4 (TLR4) is expressed on dendritic cells (DCs), sensing environmental danger molecules that induce their activation and maturation. Recently, we reported a method for the production of therapeutic DCs against melanoma, called tumor antigen-presenting cells (TAPCells), using a heat-shocked allogeneic melanoma cell lysate (TRIMEL) as an activation factor and antigen provider. Since TRIMEL contains endogenous TLR4 ligands, we evaluated the role of TLR4 in TAPCells differentiation by antibody neutralization and the association of a Tlr4 polymorphism (896A/G) (Asp299Gly), determined by PCR-RFLP, with the in vitro activation capacity and the clinical outcome of TAPCells-vaccinated patients. Antibody blocking of monocyte TLR4 inhibited surface expression, determined by flow cytometry, of the major histocompatibility complex class I, CCR7, CD80, CD83 and CD86 on TAPCells, reduced interleukin (IL)-6 and tumor necrosis factor -α gene expression evaluated by qRT-PCR, and also inhibited the TAPCells-mediated interferon-γ (IFN-γ) secretion of melanoma-specific CD8(+) T cells determined by ELISpot (p < 0.01). Moreover, CD8(+) T-cell activation capacity was significantly reduced in TAPCells bearing the TLR4 Asp299Gly receptor (p < 0.05). Finally, TAPCells-vaccinated stage-IV melanoma patients bearing the Tlr4 896G allele showed a shortened post-therapy median survival rate compared with those carrying the Tlr4 896A allele (p < 0.05; log-rank test). Our results indicate that TLR4 is a key receptor for the tumor lysate-mediated in vitro generation of clinically efficient antigen-presenting cells. Further analysis of patients included in different vaccine protocols is necessary for definitively establishing a role for TLR4 polymorphism in clinical responses.
Assuntos
Vacinas Anticâncer/uso terapêutico , Células Dendríticas/imunologia , Melanoma/terapia , Polimorfismo Genético , Neoplasias Cutâneas/terapia , Receptor 4 Toll-Like/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Neutralizantes/imunologia , Linfócitos T CD8-Positivos/imunologia , Vacinas Anticâncer/imunologia , Células Cultivadas , Citocinas/biossíntese , Citocinas/imunologia , Feminino , Humanos , Ativação Linfocitária/imunologia , Masculino , Melanoma/imunologia , Melanoma/mortalidade , Melanoma/patologia , Pessoa de Meia-Idade , Monócitos/imunologia , Estudos Retrospectivos , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/patologia , Receptor 4 Toll-Like/imunologia , Resultado do Tratamento , Adulto JovemRESUMO
We explored the association between residence in an area polluted with metals and neurobehavioral performance in children aged 9 to 11. A cross-sectional study was conducted with thirty boys and thirty girls aged 9 to 11 from public schools in a heavily industrialized area, matched by age (±4 months) and gender with 15 boys and 15 girls from public schools in cities without relevant industrial activity. Neurobehavioral performance was assessed with the Behavioral Assessment and Research System. Linear regression models were used, adjusting for age, sex, social class and multimedia activities to predict each of the neurobehavioral outcome variables. No differences in neurobehavioral performance were found when all children with residence in areas with environmental exposure to metals were classified as exposed and the children from the other provinces as unexposed. However, when we compared children living <1 km from an industrial area with respect to those living more than 1 km away, significant differences were found. Children living <1 km away had lower scores on Finger Tapping (p = 0.03), Symbol-Digit (p = 0.07) and Continuous Performance (p = 0.02) than those living farther away. Our results support the hypothesis that residing close to an area with industrial activity (<1 km) is associated with deficits in neurobehavioral performance among children aged 9 to 11.
Assuntos
Exposição Ambiental , Metais Pesados , Criança , Estudos Transversais , Exposição Ambiental/análise , Feminino , Humanos , Indústrias , MasculinoRESUMO
The hepatopulmonary syndrome (HPS) is defined by the presence of pulmonary gas exchange abnormalities due to intrapulmonary vascular dilatations in patients with chronic liver disease. Changes in DNA methylation reflect the genomic variation. Since liver transplant (LT) reverts HPS we hypothesized that it may be associated with specific liver epigenetic changes. Thus, the aim of this study was to investigate the role of the liver epigenome in patients with HPS. We extracted DNA from paraffin embedded liver tissue samples from 10 patients with HPS and 10 age-, sex- and MELD (Model for End-stage Liver Disease)-matched controls. DNA methylation was determined using the 850K array (Illumina). Weighted Gene Co-expression Network Analysis (WGCNA) was used to identify modules related to defining physiologic characteristics of HPS. Only 12 out of the 20 liver biopsies (7 HPS and 5 controls) had sufficient quality to be analyzed. None of the 802,688 DNA probes analyzed in the case control comparison achieved a significant False Discovery Rate (FDR). WGCNA identified 5 co-methylated gene-modules associated to HPS markers, mainly related to nervous and neuroendocrine system, apoptotic processes, gut bacterial translocation, angiogenesis and vascular remodeling ontologies. To conclude, HPS is associated with nervous/neuroendocrine system and vascular remodeling related liver epigenetic changes.