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Fetal growth restriction (FGR) is a common outcome in human suboptimal gestation and is related to prenatal origins of cardiovascular dysfunction in offspring. Despite this, therapy of human translational potential has not been identified. Using human umbilical and placental vessels and the chicken embryo model, we combined cellular, molecular, and functional studies to determine whether N-acetylcysteine (NAC) and hydrogen sulphide (H2S) protect cardiovascular function in growth-restricted unborn offspring. In human umbilical and placental arteries from control or FGR pregnancy and in vessels from near-term chicken embryos incubated under normoxic or hypoxic conditions, we determined the expression of the H2S gene CTH (i.e. cystathionine γ-lyase) (via quantitative PCR), the production of H2S (enzymatic activity), the DNA methylation profile (pyrosequencing) and vasodilator reactivity (wire myography) in the presence and absence of NAC treatment. The data show that FGR and hypoxia increased CTH expression in the embryonic/fetal vasculature in both species. NAC treatment increased aortic CTH expression and H2S production and enhanced third-order femoral artery dilator responses to the H2S donor sodium hydrosulphide in chicken embryos. NAC treatment also restored impaired endothelial relaxation in human third-to-fourth order chorionic arteries from FGR pregnancies and in third-order femoral arteries from hypoxic chicken embryos. This NAC-induced protection against endothelial dysfunction in hypoxic chicken embryos was mediated via nitric oxide independent mechanisms. Both developmental hypoxia and NAC promoted vascular changes in CTH DNA and NOS3 methylation patterns in chicken embryos. Combined, therefore, the data support that the effects of NAC and H2S offer a powerful mechanism of human translational potential against fetal cardiovascular dysfunction in complicated pregnancy. KEY POINTS: Gestation complicated by chronic fetal hypoxia and fetal growth restriction (FGR) increases a prenatal origin of cardiovascular disease in offspring, increasing interest in antenatal therapy to prevent against a fetal origin of cardiovascular dysfunction. We investigated the effects between N-acetylcysteine (NAC) and hydrogen sulphide (H2S) in the vasculature in FGR human pregnancy and in chronically hypoxic chicken embryos. Combining cellular, molecular, epigenetic and functional studies, we show that the vascular expression and synthesis of H2S is enhanced in hypoxic and FGR unborn offspring in both species and this acts to protect their vasculature. Therefore, the NAC/H2S pathway offers a powerful therapeutic mechanism of human translational potential against fetal cardiovascular dysfunction in complicated pregnancy.
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Acetilcisteína , Epigênese Genética , Retardo do Crescimento Fetal , Sulfeto de Hidrogênio , Hipóxia , Animais , Sulfeto de Hidrogênio/metabolismo , Acetilcisteína/farmacologia , Embrião de Galinha , Humanos , Feminino , Gravidez , Retardo do Crescimento Fetal/metabolismo , Retardo do Crescimento Fetal/genética , Retardo do Crescimento Fetal/fisiopatologia , Hipóxia/metabolismo , Hipóxia/fisiopatologia , Metilação de DNA , Cistationina gama-Liase/genética , Cistationina gama-Liase/metabolismo , Vasodilatação/efeitos dos fármacos , Placenta/metabolismo , Placenta/irrigação sanguínea , Artérias Umbilicais/metabolismoRESUMO
Advances in understanding gene expression regulation through epigenetic mechanisms have contributed to elucidating the regulatory mechanisms of noncoding RNAs as pharmacological targets in several diseases. MicroRNAs (miRs) are a class of evolutionarily conserved, short, noncoding RNAs regulating in a concerted manner gene expression at the post-transcriptional level by targeting specific sequences of the 3'-untranslated region of mRNA. Conversely, mechanisms of cardiovascular disease (CVD) remain largely elusive due to their life-course origins, multifactorial pathophysiology, and co-morbidities. In this regard, CVD treatment with conventional medications results in therapeutic failure due to progressive resistance to monotherapy, which overlooks the multiple factors involved, and reduced adherence to poly-pharmacology approaches. Consequently, considering its role in regulating complete gene pathways, miR-based drugs have appreciably progressed into preclinical and clinical testing. This review summarizes the current knowledge about the mechanisms of miRs in cardiovascular disease, focusing specifically on describing how clinical chemistry and physics have improved the stability of the miR molecule. In addition, a comprehensive review of the main miRs involved in cardiovascular disease and the clinical trials in which these molecules are used as active pharmacological molecules is provided.
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Doenças Cardiovasculares , MicroRNAs , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/terapia , Animais , Fármacos Cardiovasculares/uso terapêutico , Regulação da Expressão Gênica/efeitos dos fármacosRESUMO
PIEZO1 is a mechanosensitive cation channel implicated in shear stress-mediated endothelial-dependent vasorelaxation. Since altered shear stress patterns induce a pro-inflammatory endothelial environment, we analyzed transcriptional profiles of human endothelial cells to determine the effect of altered shear stress patterns and subsequent prooxidant and inflammatory conditions on PIEZO1 and mechanosensitive-related genes (MRG). In silico analyses were validated in vitro by assessing PIEZO1 transcript levels in both the umbilical artery (HUAEC) and vein (HUVEC) endothelium. Transcriptional profiling showed that PIEZO1 and some MRG associated with the inflammatory response were upregulated in response to high (15 dyn/cm2) and extremely high shear stress (30 dyn/cm2) in HUVEC. Changes in PIEZO1 and inflammatory MRG were paralleled by p65 but not KLF or YAP1 transcription factors. Similarly, PIEZO1 transcript levels were upregulated by TNF-alpha (TNF-α) in diverse endothelial cell types, and pre-treatment with agents that prevent p65 translocation to the nucleus abolished PIEZO1 induction. ChIP-seq analysis revealed that p65 bonded to the PIEZO1 promoter region, an effect increased by the stimulation with TNF-α. Altogether this data showed that NF-kappa B activation via p65 signaling regulates PIEZO1 expression, providing a new molecular link for prooxidant and inflammatory responses and mechanosensitive pathways in the endothelium.
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BACKGROUND: Biometrical and blood flow examinations are fundamental for assessing fetoplacental development during pregnancy. Guinea pigs have been proposed as a good model to study fetal development and related gestational complications; however, longitudinal growth and blood flow changes in utero have not been properly described. This study aimed to describe fetal and placental growth and blood flow of the main intrauterine vascular beds across normal guinea pig pregnancy and to discuss the relevance of this data for human pregnancy. METHODS: Pregnant guinea pigs were studied from day 25 of pregnancy until term (day ~70) by ultrasound and Doppler assessment. The results were compared to human data from the literature. RESULTS: Measurements of biparietal diameter (BPD), cranial circumference (CC), abdominal circumference, and placental biometry, as well as pulsatility index determination of umbilical artery, middle cerebral artery (MCA), and cerebroplacental ratio (CPR), were feasible to determine across pregnancy, and they could be adjusted to linear or nonlinear functions. In addition, several of these parameters showed a high correlation coefficient and could be used to assess gestational age in guinea pigs. We further compared these data to ultrasound variables from human pregnancy with high similarities. CONCLUSIONS: BPD and CC are the most reliable measurements to assess fetal growth in guinea pigs. Furthermore, this is the first report in which the MCA pulsatility index and CPR are described across guinea pig gestation. The guinea pig is a valuable model to assess fetal growth and blood flow distribution, variables that are comparable with human pregnancy.
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Umbilical and placental vessels and endothelial cells (EC) are common models to study placental function and vascular programming. Arterio-venous differences are present in the umbilical endothelium; however, the heterogeneity of small placental vessels and the expression of potential micro- vs. macro-vascular (MMV) markers are poorly described. Here, we performed a meta-analysis of transcriptomic and DNA methylation data from placental and umbilical EC. Expression and methylation profiles were compared using hierarchical clustering, dimensionality reduction (i.e., tSNE, MDS, and PHATE), and enrichment analysis to determine the occurrence of arterio-venous (AVH) and micro-macro heterogeneity (MMH). CpG sites correlated with gene expression of transcriptional markers of MMH and AVH were selected by Lasso regression and used for EC discrimination. General transcriptional profile resulted in clear segregation of EC by their specific origin. MM and AVH grouping were also observed when microvascular markers were applied. Altogether, this meta-analysis provides cogent evidence regarding the transcriptional and epigenomic profiles that differentiate among EC, proposing novel markers to define phenotypes based on MM levels.
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Células Endoteliais , Placenta , Biomarcadores/metabolismo , Metilação de DNA , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Epigenômica , Feminino , Humanos , Placenta/metabolismo , GravidezRESUMO
Whether arterial-venous differences of primary endothelial cells commonly used for vascular research are preserved in vitro remains under debate. To address this issue, a meta-analysis of Affymetrix transcriptomic data sets from human umbilical artery (HUAECs) and vein (HUVEC) endothelial cells was performed. The meta-analysis showed 2,742 transcripts differentially expressed (false discovery rate <0.05), of which 78% were downregulated in HUVECs. Comparisons with RNA-seq data sets showed high levels of agreement and correlation (p < 0.0001), identifying 84 arterial-venous identity markers. Functional analysis revealed enrichment of key vascular processes in HUAECs/HUVECs, including nitric oxide- (NO) and hypoxia-related genes, as well as differences in miRNA- and ncRNA-mRNA interaction profiles. A proof of concept of these findings in primary cells exposed to hypoxia in vitro and in vivo confirmed the arterial-venous differences in NO-related genes and miRNAs. Altogether, these data defined a cross-platform arterial-venous transcript profile for cultured HUAEC-HUVEC and support a preserved identity involving key vascular pathways post-transcriptionally regulated in vitro.
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Diagnosing asthma in preschool children remains an unsolved challenge, at a time when early identification would allow for better education and treatment to prevent morbidity and lung function deterioration. OBJECTIVE: To evaluate if the asthma predictive index (API) can be used as surrogate for asthma diagnosis in preschoolers. METHODS: Birth cohort of 339 pregnant women enrolled at delivery and their offspring, who were followed for atopy, wheezing, and other respiratory illnesses through 30 months of age. The API was determined at 30 months of age by the researchers; and examined its association with physician-diagnosed asthma during the first 30 months, made independently by the primary care physician not involved in the study. RESULTS: Among 307 offspring with complete follow-up, 44 (14.3%) were API+. Maternal body mass index, maternal education, past oral contraceptive use, birthweight, placenta weight, age of daycare at 12 m, gastroesophageal reflux disease at 12 m, acute otitis media at 18 m, bronchiolitis, croup and pneumonia, cord blood adiponectin were all associated with API+. In the multivariable analysis, API+ was associated with almost sixfold odds of asthma diagnosis (adjusted OR = 5.7, 95% CI [2.6-12.3]), after adjusting for the relevant covariates above including respiratory infections like bronchiolitis and pneumonia. The API sensitivity was 48%, specificity 92%, 61% PPV, 88% NPV, 6.4 LR+, 0.56 LR-, 0.84 diagnosis accuracy. The adjusted odds for asthma was 11.4. CONCLUSIONS: This longitudinal birth cohort suggests, for first time, that API (a structured definition for asthma), could be used as a diagnostic tool, not only as a prognostic tool, in toddlers and preschoolers.
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Asma , Hipersensibilidade Imediata , Infecções Respiratórias , Asma/diagnóstico , Asma/epidemiologia , Coorte de Nascimento , Pré-Escolar , Feminino , Humanos , Lactente , Gravidez , Sons Respiratórios/diagnóstico , Sons Respiratórios/etiologiaRESUMO
More than 30 years have passed since endothelial nitric oxide synthesis was described using the umbilical artery and vein endothelium. That seminal report set the cornerstone for unveiling the molecular aspects of endothelial function. In parallel, the understanding of placental physiology has gained growing interest, due to its crucial role in intrauterine development, with considerable long-term health consequences. This review discusses the evidence for nitric oxide (NO) as a critical player of placental development and function, with a special focus on endothelial nitric oxide synthase (eNOS) vascular effects. Also, the regulation of eNOS-dependent vascular responses in normal pregnancy and pregnancy-related diseases and their impact on prenatal and postnatal vascular health are discussed. Recent and compelling evidence has reinforced that eNOS regulation results from a complex network of processes, with novel data concerning mechanisms such as mechano-sensing, epigenetic, posttranslational modifications, and the expression of NO- and l-arginine-related pathways. In this regard, most of these mechanisms are expressed in an arterial-venous-specific manner and reflect traits of the fetal systemic circulation. Several studies using umbilical endothelial cells are not aimed to understand placental function but general endothelial function, reinforcing the influence of the placenta on general knowledge in physiology.
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Endotélio Vascular/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Óxido Nítrico/metabolismo , Placenta/metabolismo , Feminino , Feto/metabolismo , Humanos , Gravidez , Veias Umbilicais/metabolismoRESUMO
Adverse childhood experiences (ACEs) are associated with a high risk of developing chronic diseases and decreased life expectancy, but no ACE epigenetic biomarkers have been identified until now. The latter may result from the interaction of multiple factors such as age, sex, degree of adversity, and lack of transcriptional effects of DNA methylation changes. We hypothesize that DNA methylation changes are related to childhood adversity levels and current age, and these markers evolve as aging proceeds. Two Gene Expression Omnibus datasets, regarding ACE, were selected (GSE72680 and GSE70603), considering raw- and meta-data availability, including validated ACE index (Childhood Trauma Questionnaire (CTQ) score). For DNA methylation, analyzed probes were restricted to those laying within promoters and first exons, and samples were grouped by CTQ scores terciles, to compare highly (ACE) with non-abused (control) cases. Comparison of control and ACE methylome profile did not retrieve differentially methylated CpG sites (DMCs) after correcting by false discovery rate < 0.05, and this was also observed when samples were separated by sex. In contrast, grouping by decade age ranges (i.e., the 20s, 30s, 40s, and 50s) showed a progressive increase in the number of DMCs and the intensity of changes, mainly related with hypomethylation. Comparison with transcriptome data for ACE subjects in the 40s, and 50s showed a similar age-dependent effect. This study provides evidence that epigenetic markers of ACE are age-dependent, but not defined in the long term. These differences among early, middle, and late adulthood epigenomic profiles suggest a window for interventions aimed to prevent the detrimental effects of ACE.
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Experiências Adversas da Infância/classificação , Envelhecimento/psicologia , Metilação de DNA/fisiologia , Fatores de Tempo , Adulto , Epigênese Genética/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Aim: To determine changes in global DNA methylation in monocytes from neonates of women with obesity, as markers of an immune programming resulting from maternal obesity. Materials & methods: Cord blood monocytes were obtained from neonates born to women with obesity and normal weight, genome-wide differentially methylated CpGs were determined using an Infinium MethylationEPIC-BeadChip (850K). Results: No clustering of samples according to maternal BMI was observed, but sex-specific analysis revealed 71,728 differentially methylated CpGs in female neonates from women with obesity (p < 0.01). DAVID analysis showed increased methylation levels within genes involved in the innate immune response and inflammation. Conclusion: Maternal obesity induces, in a sex-specific manner, an epigenetic programming of monocytes that could contribute to disease later in life. Clinical trial registry: This study is registered in ClinicalTrials.gov NCT02903134.
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Epigênese Genética , Monócitos/metabolismo , Obesidade Materna , Adolescente , Adulto , Células Cultivadas , Ilhas de CpG , Metilação de DNA , Feminino , Humanos , Imunidade Inata/genética , Recém-Nascido , Mediadores da Inflamação/sangue , Masculino , Gravidez , Caracteres Sexuais , Adulto JovemRESUMO
Aim: To evaluate the risk of nonsyndromic orofacial clefts (NSOFCs) associated with LINE-1 methylation, as a marker of global DNA methylation, and the effect of MTHFR functional variants on this variable. Patients & methods: LINE-1 methylation was evaluated by bisulfite modification coupled to DNA pyrosequencing in 95 NSOFC cases and 95 controls. In these subjects, MTHFR genotypes for variants c.C677T (rs1801133) and c.A1298C (rs1801131) were obtained. Results: Middle levels (second tertile) of LINE-1 methylation increase the risk of NSOFCs. In addition, LINE-1 methylation depends on c.A1298C genotypes in controls but not in cases. Conclusion: A nonlinear association between global DNA methylation and NSOFCs was detected in this Chilean population, which appears to be influenced by MTHFR functional variants.
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Encéfalo/anormalidades , Fenda Labial/genética , Fissura Palatina/genética , Metilação de DNA , Elementos Nucleotídeos Longos e Dispersos , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Chile , Humanos , Lactente , Recém-Nascido , Polimorfismo de Nucleotídeo ÚnicoRESUMO
Clinical conditions associated with hypoxia and oxidative stress, such as fetal growth restriction (FGR), results in endothelial dysfunction. Previous reports show that changes in eNOS expression under these conditions are tightly controlled by DNA methylation and histone posttranslational modifications. However, the contribution of an orchestrating epigenetic mechanism, such as miRNAs, on the NO-related genes expression has not been addressed. We aimed to determine the levels of miRNAs highly expressed in normal endothelial cells (EC), miR-21 and miR-126, in FGR human umbilical artery EC (HUAEC), and their effects on hypoxia-dependent regulation of both, NO-related and oxidative stress-related genes. Results were validated by transcriptome analysis of HUAEC cultured under chronic low oxygen conditions. Cultured FGR-HUAEC showed decreased hsa-miR-21, DDAH1, SOD1, and NRF2, but increased miR-126, NOX4, and eNOS levels, compared with controls. MiR-21-5p levels in FGR were associated with increased hg-miR-21 gene promoter methylation, with no changes in hg-miR-126 gene promoter methylation. HUAEC exposed to hypoxia showed a transient increase in eNOS and DDAH11, paralleled by decrease miR-21-5p levels, but no changes in miR-126-3p and the other genes under study. Transcriptome profiling showed an inverse relationship among miR-21 and several transcripts targeted by miR-21 in HUAEC exposed to hypoxia, meanwhile miR-21-5p-mimic decreased eNOS and DDAH1 transcripts stability, blocking their induction by hypoxia. Consequently, FGR programs a hypoxia-related miRNA that contributes to the regulation of the NO pathway, involving a direct effect of miR-21-5p on eNOS transcript stability, not previously reported. Moreover, hypoxia downregulates miR-21-5p, contributing to increasing the expression of NO-related genes in arterial endothelial cells.
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Endotélio Vascular/metabolismo , Regulação Enzimológica da Expressão Gênica , MicroRNAs/metabolismo , Óxido Nítrico Sintase Tipo III/biossíntese , Artérias Umbilicais/metabolismo , Hipóxia Celular/fisiologia , Células Cultivadas , Feminino , Humanos , Recém-Nascido , Masculino , MicroRNAs/antagonistas & inibidores , Óxido Nítrico Sintase Tipo III/genética , GravidezRESUMO
Obstructive sleep apnea (OSA), a breathing disorder featured by chronic intermittent hypoxia (CIH) is associated with pulmonary hypertension (PH). Rodents exposed to CIH develop pulmonary vascular remodeling and PH, but the pathogenic mechanisms are not well known. Overexpression of Stim-activated Transient Receptor Potential Channels (TRPC) and Calcium Release-Activated Calcium Channel Protein (ORAI) TRPC-ORAI Ca2+ channels (STOC) has been involved in pulmonary vascular remodeling and PH in sustained hypoxia. However, it is not known if CIH may change STOC levels. Accordingly, we studied the effects of CIH on the expression of STOC subunits in the lung and if these changes paralleled the progression of the vascular pulmonary remodeling and PH in a preclinical model of OSA. Male Sprague-Dawley rats (â¼200 g) were exposed to CIH (5%O2, 12 times/h for 8 h) for 14, 21, and 28 days. We measured right ventricular systolic pressure (RVSP), cardiac morphometry with MRI, pulmonary vascular remodeling, and wire-myographic arterial responses to KCl and endothelin-1 (ET-1). Pulmonary RNA and protein STOC levels of TRPC1, TRPC4, TRPC6, ORAI 1, ORAI 2, and STIM1 subunits were measured by qPCR and western blot, and results were compared with age-matched controls. CIH elicited a progressive increase of RVSP and vascular contractile responses to KCl and ET-1, leading to vascular remodeling and augmented right ventricular ejection fraction, which was significant at 28 days of CIH. The levels of TRPC1, TRPC4, TRPC 6, ORAI 1, and STIM 1 channels increased following CIH, and some of them paralleled morphologic and functional changes. Our findings show that CIH increased pulmonary STOC expression, paralleling vascular remodeling and PH.
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Methylation in CpG sites of the PPARGC1A gene (encoding PGC1-α) has been associated with adiposity, insulin secretion/sensitivity indexes and type 2 diabetes. We assessed the association between the methylation profile of the PPARGC1A gene promoter gene in leukocytes with insulin secretion/sensitivity indexes in normoglycemic women. A standard oral glucose tolerance test (OGTT) and an abbreviated version of the intravenous glucose tolerance test (IVGTT) were carried out in n = 57 Chilean nondiabetic women with measurements of plasma glucose, insulin, and C-peptide. Bisulfite-treated DNA from leukocytes was evaluated for methylation levels in six CpG sites of the proximal promoter of the PPARGC1A gene by pyrosequencing (positions -816, -783, -652, -617, -521 and -515). A strong correlation between the DNA methylation percentage of different CpG sites of the PPARGC1A promoter in leukocytes was found, suggesting an integrated epigenetic control of this region. We found a positive association between the methylation levels of the CpG site -783 with the insulin sensitivity Matsuda composite index (rho = 0.31; p = 0.02) derived from the OGTT. The CpG hypomethylation in the promoter position -783 of the PPARGC1A gene in leukocytes may represent a biomarker of reduced insulin sensitivity after the ingestion of glucose.
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Glicemia , Metilação de DNA/genética , Resistência à Insulina/genética , Secreção de Insulina/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Regiões Promotoras Genéticas/genética , Adulto , Biomarcadores/sangue , Chile , Feminino , HumanosRESUMO
Adverse childhood experiences (ACE) impair health and life expectancy and may result in an epigenetic signature that drives increased morbidity primed during early stages of life. This literature review focuses on the current evidence for epigenetic-mediated programming of brain and immune function resulting from ACE. To address this aim, a total of 88 articles indexed in PubMed before August 2019 concerning ACE and epigenetics were surveyed. Current evidence partially supports epigenetic programming of the hypothalamic-pituitary-adrenal axis, but convincingly shows that ACE impairs immune function. Additionally, the needs and challenges that face this area are discussed in order to provide a framework that may help to clarify the role of epigenetics in the long-lasting effects of ACE.
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Experiências Adversas da Infância , Epigênese Genética , Sistema Hipotálamo-Hipofisário , Sistema Hipófise-Suprarrenal , Criança , Metilação de DNA , Histonas/genética , Humanos , Sistema Hipotálamo-Hipofisário/fisiopatologia , Sistema Imunitário , Sistema Hipófise-Suprarrenal/fisiopatologia , Processamento de Proteína Pós-Traducional , RNA não Traduzido/genética , Estresse FisiológicoRESUMO
Cardiovascular risk associated with fetal growth restriction (FGR) could result from an early impaired vascular function. However, whether this effect results in premature vascular aging has not been addressed. We studied the ex vivo reactivity of carotid and femoral arteries in fetal (near term), adults (eight months-old) and aged (16 months-old) guinea pigs in normal (control) and FGR offspring. Additionally, an epigenetic marker of vascular aging (i.e., LINE-1 DNA methylation) was evaluated in human umbilical artery endothelial cells (HUAEC) from control and FGR subjects. Control guinea pig arteries showed an increased contractile response (KCl-induced) and a progressive impairment of NO-mediated relaxing responses as animals get older. FGR was associated with an initial preserved carotid artery reactivity as well as a later significant impairment in NO-mediated responses. Femoral arteries from FGR fetuses showed an increased contractility but a decreased relaxing response compared with control fetuses, and both responses were impaired in FGR-adults. Finally, FGR-HUAEC showed decreased LINE-1 DNA methylation compared with control-HUAEC. These data suggest that the aging of vascular function occurs by changes in NO-mediated responses, with limited alterations in contractile capacity. Further, these effects are accelerated and imposed at early stages of development in subjects exposed to a suboptimal intrauterine environment.
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Envelhecimento/patologia , Endotélio Vascular/crescimento & desenvolvimento , Retardo do Crescimento Fetal/patologia , Animais , Artérias Carótidas/crescimento & desenvolvimento , Artérias Carótidas/patologia , Artérias Carótidas/fisiopatologia , Células Cultivadas , Metilação de DNA , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Feminino , Artéria Femoral/crescimento & desenvolvimento , Artéria Femoral/patologia , Artéria Femoral/fisiopatologia , Retardo do Crescimento Fetal/genética , Cobaias , Humanos , Elementos Nucleotídeos Longos e Dispersos/genética , Óxido Nítrico/metabolismo , Vasoconstrição , VasodilataçãoRESUMO
AIM: Foetal growth restriction (FGR) is associated with endothelial dysfunction and cardiovascular diseases in adult subjects. Early vascular remodelling and epigenetic changes occurring on key endothelial genes might precede this altered vascular function. Further, it has been proposed that oxidative stress during development may determine some of these epigenetic modifications. To address this issue, we studied the in vivo and ex vivo vascular function and Nos3 promoter DNA methylation in arteries from eight-month-old guinea-pig born from control, FGR-treated and FGR-NAC-treated pregnancies. METHODS: Femoral and carotid arteries in vivo vascular function were determined by Doppler, whilst ex vivo vascular function and biomechanical properties were assessed by wire myography. Levels of eNOS mRNA and site-specific DNA methylation in Nos3 promoter in aorta endothelial cells (AEC) were determined by qPCR and pyrosequencing respectively. RESULTS: FGR adult showed an increased femoral vascular resistance (P < .05), stiffness (P < .05) and arterial remodelling (P < .01), along with an impaired NO-mediated relaxation (P < .001). These effects were prevented by maternal treatment with NAC. Endothelial-NOS mRNA levels were decreased in FGR adult compared with control and FGR-NAC (P < .05), associated with increased DNA methylation levels (P < .01). Comparison of Nos3 DNA methylation in AEC showed a differential methylation pattern between foetal and adult guinea-pigs (P < .05). CONCLUSION: Altogether, these data suggest that adult vascular dysfunction in the FGR does not result from early changes in Nos3 promoter DNA methylation, but from an altered vessel structure established during foetal development.
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Retardo do Crescimento Fetal , Óxido Nítrico Sintase Tipo III/metabolismo , Animais , Fenômenos Biomecânicos , Artérias Carótidas/patologia , Metilação de DNA , Epigênese Genética , Feminino , Artéria Femoral/patologia , Desenvolvimento Fetal , Regulação da Expressão Gênica no Desenvolvimento , Cobaias , Óxido Nítrico Sintase Tipo III/genética , GravidezRESUMO
Chronic intermittent hypoxia (CIH), the main attribute of obstructive sleep apnea (OSA), produces oxidative stress, endothelial dysfunction, and hypertension. Nitric oxide (NO) plays a critical role in controlling the vasomotor tone. The NO level depends on the L-arginine level, which can be reduced by arginase enzymatic activity, and its reaction with the superoxide radical to produce peroxynitrite. Accordingly, we hypothesized whether a combination of an arginase inhibitor and an antioxidant may restore the endothelial function and reduced arterial blood pressure (BP) in CIH-induced hypertensive rats. Male Sprague-Dawley rats 200 g were exposed either to CIH (5% O2, 12 times/h 8 h/day) or sham condition for 35 days. BP was continuously measured by radio-telemetry in conscious animals. After 14 days, rats were treated with 2(S)-amino-6-boronohexanoic acid (ABH 400 µg/kg day, osmotic pump), N-acetylcysteine (NAC 100 mg/kg day, drinking water), or the combination of both drugs until day 35. At the end of the experiments, external carotid and femoral arteries were isolated to determine vasoactive contractile responses induced by KCL and acetylcholine (ACh) with wire-myography. CIH-induced hypertension (~8 mmHg) was reverted by ABH, NAC, and ABH/NAC administration. Carotid arteries from CIH-treated rats showed higher contraction induced by KCl (3.4 ± 0.4 vs. 2.4 ± 0.2 N/m2) and diminished vasorelaxation elicits by ACh compared to sham rats (12.8 ± 1.5 vs. 30.5 ± 4.6%). ABH reverted the increased contraction (2.5 ± 0.2 N/m2) and the reduced vasorelaxation induced by ACh in carotid arteries from CIH-rats (38.1 ± 4.9%). However, NAC failed to revert the enhanced vasocontraction (3.9 ± 0.6 N/m2) induced by KCl and the diminished ACh-induced vasorelaxation in carotid arteries (10.7 ± 0.8%). Femoral arteries from CIH rats showed an increased contractile response, an effect partially reverted by ABH, but completely reverted by NAC and ABH/NAC. The impaired endothelial-dependent relaxation in femoral arteries from CIH rats was reverted by ABH and ABH/NAC. In addition, ABH/NAC at high doses had no effect on liver and kidney gross morphology and biochemical parameters. Thus, although ABH, and NAC alone and the combination of ABH/NAC were able to normalize the elevated BP, only the combined treatment of ABH/NAC normalized the vascular reactivity and the systemic oxidative stress in CIH-treated rats.
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Fetal growth restriction (FGR) is a perinatal condition associated with a low birth weight that results mainly from maternal and placental constrains. Newborns affected by this condition are more likely to develop in the long term cardiovascular diseases whose origins would be in an altered vascular structure and function defined during fetal development. Thus, this study presents the modeling and numerical simulation of systemic vessels from guinea pig fetuses affected by FGR. We aimed to characterize the biomechanical properties of the arterial wall of FGR-derived the aorta, carotid, and femoral arteries by performing ring tensile and ring opening tests and, based on these data, to simulate the biomechanical behavior of FGR vessels under physiological conditions. The material parameters were first obtained from the experimental data of the ring tensile test. Then, the residual stresses were determined from the ring opening test and taken as initial stresses in the simulation of the ring tensile test. These two coupled steps are iteratively considered in a nonlinear least-squares algorithm to obtain the final material parameters. Then, the stress distribution changes along the arterial wall under physiological pressure were quantified using the adjusted material parameters. Overall, the obtained results provide a realistic approximation of the residual stresses and the changes in the mechanical behavior under physiological conditions.
Assuntos
Artérias , Retardo do Crescimento Fetal , Fenômenos Mecânicos , Animais , Fenômenos Biomecânicos , Feminino , Cobaias , Masculino , Teste de Materiais , Pressão , Resistência à TraçãoRESUMO
Maternal obesity is associated with large-for-gestational-age (LGA) neonates and programming of obesity-related cardiovascular disease in the offspring, however, the mechanisms that lead to the later are unclear. Presently, interpretations of NO-dependent changes in vascular function in LGA newborn from obese mothers are conflicting. Adiponectin improves endothelial function by increasing eNOS activity and NO production. We propose that LGAs from obese mothers present a diminished vascular response to adiponectin; thus, affecting eNOS and AMPK activation. Chorionic arteries, umbilical cord and primary cultures of umbilical artery endothelial cells (HUAEC) were collected at term (>38 weeks) from uncomplicated singleton pregnancies of LGA and adequate-for-gestational (AGA) newborn. Vascular reactivity of chorionic plate arteries was assessed by wire myography. mRNA expression of adiponectin receptors 1 (AdipoR1) and AdipoR2 in HUAEC was determined by qPCR. Protein expression of AdipoR1, AdipoR2, AMPK, phospho-AMPKαThr172 , eNOS, and phospho-eNOSSer1177 after stimulation with AdipoRon was determined by Western Blot. Maximal adiponectin-induced chorionic artery relaxation in LGAs was diminished compared to control. In vitro studies showed no differences in expression of AdipoRs, total AMPK and, eNOS activation between groups; however, higher expression of total eNOS and AMPK activation in HUAEC of LGA relative to AGAs were observed. LGA HUAEC showed diminished NO production and eNOS activity compared to AGA in response to AdipoRon but no changes in AMPK activation. Placental endothelium of LGAs shows a diminished vascular response to adiponectin. Moreover, eNOS activation and adiponectin-dependent NO production is lower in HUAEC of LGA from obese mothers, indicating they present dysfuncional placental-endothelial responses.