RESUMO
BACKGROUND AND AIMS: Fetal and postnatal growth restriction cause a predisposition to cardiovascular disease (CVD) in adulthood. Telomeres are repetitive DNA-protein structures that protect chromosome ends, and the loss of these repeats (a reduction in telomere length) is associated with CVD. As exercise preserves telomere length and cardiovascular health, the aim of this study was to determine the effects of growth restriction and exercise training on cardiac telomere length and telomeric genes. METHODS AND RESULTS: Pregnant Wistar Kyoto rats underwent bilateral uterine vessel ligation to induce uteroplacental insufficiency and fetal growth restriction ("Restricted"). Sham-operated rats had either intact litters ("Control") or their litters reduced to five pups with slowed postnatal growth ("Reduced"). Control, Restricted, and Reduced male rats were assigned to Sedentary, Early exercise (5-9 wk of age), or Late exercise (20-24 wk of age) groups. Hearts were excised at 24 wk of age for telomere length and gene expression measurements by quantitative PCR. Growth restriction shortened cardiac telomere length ( P < 0.001), but this was rescued by early exercise ( P < 0.001). Early and Late exercise increased cardiac weight index ( P < 0.001), but neither this nor telomere length was associated with expression of the telomeric genes Tert, Terc, Trf2, Pnuts, or Sirt1. DISCUSSION AND CONCLUSIONS: Growth restriction shortens cardiac telomere length, reflecting the cardiac pathologies associated with low birth weight. Exercise in early life may offer long-term protective effects on cardiac telomere length, which could help prevent CVD in later life.
Assuntos
Retardo do Crescimento Fetal/genética , Coração/fisiologia , Telômero/genética , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Peso ao Nascer , Feminino , Regulação da Expressão Gênica , Coração/crescimento & desenvolvimento , Tamanho da Ninhada de Vivíparos , Masculino , Condicionamento Físico Animal , Gravidez , Ratos Endogâmicos WKY , Proteínas Semelhantes à Proteína de Ligação a TATA-Box/genéticaRESUMO
Hypertrophic cardiomyopathy thickens heart muscles, reducing functionality and increasing risk of cardiac disease and morbidity. Genetic factors are involved, but their contribution is poorly understood. We used the hypertrophic heart rat (HHR), a unique normotensive polygenic model of cardiac hypertrophy and heart failure, to investigate the role of genes associated with monogenic human cardiomyopathy. We selected 42 genes involved in monogenic human cardiomyopathies to study: 1) DNA variants, by sequencing the whole genome of 13-wk-old HHR and age-matched normal heart rat (NHR), its genetic control strain; 2) mRNA expression, by targeted RNA-sequencing in left ventricles of HHR and NHR at 5 ages (2 days old and 4, 13, 33, and 50 wk old) compared with human idiopathic dilated cardiomyopathy data; and 3) microRNA expression, with rat microRNA microarrays in left ventricles of 2-day-old HHR and age-matched NHR. We also investigated experimentally validated microRNA-mRNA interactions. Whole-genome sequencing revealed unique variants mostly located in noncoding regions of HHR and NHR. We found 29 genes differentially expressed in at least 1 age. Genes encoding desmoglein 2 ( Dsg2) and transthyretin ( Ttr) were significantly differentially expressed at all ages in the HHR, but only Ttr was also differentially expressed in human idiopathic cardiomyopathy. Lastly, only two microRNAs differentially expressed in the HHR were present in our comparison of validated microRNA-mRNA interactions. These two microRNAs interact with five of the genes studied. Our study shows that genes involved in monogenic forms of human cardiomyopathies may also influence polygenic forms of the disease.
Assuntos
Cardiomegalia/genética , Cardiomiopatias/genética , Herança Multifatorial/genética , Animais , Sítios de Ligação , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Estudo de Associação Genômica Ampla , Humanos , Miocárdio/metabolismo , Miocárdio/patologia , Polimorfismo de Nucleotídeo Único/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Análise de Sequência de DNARESUMO
Norepinephrine released from sympathetic nerves is removed from the neuroeffector junction via the action of the norepinephrine transporter (NET). NET impairment is evident in several clinically important conditions including major depressive disorder (MDD), panic disorder (PD), essential hypertension and the postural orthostatic tachycardia syndrome (POTS). We aimed to determine whether a single nucleotide polymorphism (SNP) in the 3' untranslated region (UTR) of the NET gene is associated with NET impairment and to elucidate the mechanisms involved. The analyses were carried out in two cohorts of European ancestry, which included healthy controls and MDD, PD, hypertensive and POTS patients. Compared with controls, cases had significantly higher prevalence of the T allele of rs7194256 (C/T), arterial norepinephrine, depression and anxiety scores, larger left ventricular mass index, higher systolic and diastolic blood pressures, and heart rate. Bioinformatic analysis identified that the microRNA miR-19a-3p could bind preferentially to the sequence created by the presence of the T allele. This was supported by results of luciferase assays. Compared with controls, cases had significantly lower circulating miR-19a-3p, which was associated with pathways related to blood pressure and regulation of neurotransmission. In vitro norepinephrine downregulated miR-19a-3p. In conclusion, the T allele of the rs7194256 SNP in the 3'UTR of the NET gene is more prevalent in diseases where NET impairment is evident. This might be explained by the creation of a binding site for the microRNA miR-19a-3p. A defect in NET function may potentiate the sympathetic neurochemical signal, predisposing individuals with affective diseases to increased risk of cardiovascular disease development.
Assuntos
Proteínas da Membrana Plasmática de Transporte de Norepinefrina/genética , Regiões 3' não Traduzidas/genética , Adulto , Alelos , Sítios de Ligação , Doenças Cardiovasculares , Estudos de Coortes , Biologia Computacional , Transtorno Depressivo Maior/genética , Hipertensão Essencial , Feminino , Frequência Cardíaca , Humanos , Hipertensão/genética , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Norepinefrina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Norepinefrina/metabolismo , Transtorno de Pânico/genética , Polimorfismo de Nucleotídeo Único/genética , Síndrome da Taquicardia Postural Ortostática/genética , População Branca/genéticaRESUMO
Although several studies have demonstrated an association between the 7-repeat (7R) allele in the 48-bp variable number of tandem repeats (VNTRs) in the exon 3 at dopamine receptor D4 (DRD4) gene and attention-deficit/hyperactivity disorder (ADHD), others failed to replicate this finding. In this study, a total of 786 individuals with ADHD were genotyped for DRD4 exon 3 VNTR. All 7R homozygous subjects were selected for VNTR re-sequencing. Subjects homozygous for the 4R allele were selected paired by age, ancestry and disorder subtypes in order to have a sample as homogeneous as possible with 7R/7R individuals. Using these criteria, 103 individuals (66 with ADHD and 37 control individuals) were further investigated. An excess of rare variants were observed in the 7R alleles of ADHD patient when compared with controls (P=0.031). This difference was not observed in 4R allele. Furthermore, nucleotide changes that predict synonymous and non-synonymous substitutions were more common in the 7R sample (P=0.008 for total substitutions and P=0.043 for non-synonymous substitutions). In silico prediction of structural/functional alterations caused by these variants have also been observed. Our findings suggest that not only repeat length but also DNA sequence should be assessed to better understand the role of DRD4 exon 3 VNTR in ADHD genetic susceptibility.
Assuntos
Alelos , Transtorno do Deficit de Atenção com Hiperatividade/genética , Predisposição Genética para Doença/genética , Variação Genética/genética , Receptores de Dopamina D4/genética , Adulto , Sequência de Aminoácidos/genética , Sequência de Bases , Criança , Éxons/genética , Feminino , Genótipo , Humanos , Masculino , Repetições Minissatélites/genética , Dados de Sequência MolecularRESUMO
Blood pressure(BP) management interventions have been shown to be more effective when accompanied by appropriate patient education. As high BP remains poorly controlled, there may be gaps in patient knowledge and education. Therefore, this study aimed to identify specific content and delivery preferences for information to support BP management among Australian adults from the general public. Given that BP management is predominantly undertaken by general practitioners(GPs), information preferences to support BP management were also ascertained from a small sample of Australian GPs. An online survey of adults was conducted to identify areas of concern for BP management to inform content preferences and preferred format for information delivery. A separate online survey was also delivered to GPs to determine preferred information sources to support BP management. Participants were recruited via social media. General public participants (n = 465) were mostly female (68%), >60 years (57%) and 49% were taking BP-lowering medications. The management of BP without medications, and role of lifestyle in BP management were of concern among 30% and 26% of adults respectively. Most adults (73%) preferred to access BP management information from their GP. 57% of GPs (total n = 23) preferred information for supporting BP management to be delivered via one-page summaries. This study identified that Australian adults would prefer more information about the management of BP without medications and via lifestyle delivered by their GP. This could be achieved by providing GPs with one-page summaries on relevant topics to support patient education and ultimately improve BP management.
RESUMO
Patients in end-stage renal disease (ESRD) present reduced quality of life (QOL) and impaired sexual function. Previous studies have mostly addressed male sexual dysfunction. This was a cross-sectional controlled study that applied a general and the World Health Organization Quality of Life-bref questionnaires to assess demographic, marital, and sexual conditions, and QOL in 86 healthy women aged 18 or more years (Group 1), and 38 female ESRD patients on dialysis for at least 2 months (Group 2). The effect of several explanatory variables upon QOL components was estimated. Quality of life was lower in Group 2 -- overall, and on physical and environment domains. To undergo dialysis and to be poorly educated negatively affected the QOL. Yet age, a stable marital relationship or being sexually active had no effect. Female patients undergoing chronic dialysis had lower QOL and were significantly more sexually dysfunctional than comparable healthy women. Decline in sexual function had no effect on the QOL.
Assuntos
Diálise , Qualidade de Vida , Comportamento Sexual , Doença Crônica , Feminino , Humanos , Pessoa de Meia-Idade , Qualidade de Vida/psicologia , Comportamento Sexual/psicologia , Disfunções Sexuais Fisiológicas , Inquéritos e Questionários , Organização Mundial da SaúdeRESUMO
Unravelling the complete genetic predisposition to high blood pressure (BP) has proven to be challenging. This puzzle and the fact that coding regions of the genome account for less than 2% of the entire human DNA support the hypothesis that genetic mechanism besides coding genes are likely to contribute to BP regulation. Non-coding RNAs (ncRNAs) are emerging as key players of transcription regulation in both health and disease states. They control basic functions in virtually all cell types relevant to the cardiovascular system and, thus, a direct involvement with BP regulation is highly probable. Here, we review the literature about ncRNAs associated with human BP and essential hypertension, highlighting investigations, methodology and difficulties arising in the field. The most investigated ncRNAs so far are microRNAs (miRNAs), small ncRNAs that modulate gene expression by posttranscriptional mechanisms. We discuss studies that have examined miRNAs associated with BP in biological fluids, such as blood and urine, and tissues, such as vascular smooth muscle cells and the kidney. Furthermore, we review the interaction between miRNA binding sites and single nucleotide polymorphisms in genes associated with BP. In conclusion, there is a clear need for more human and functional studies to help elucidate the multifaceted roles of ncRNAs, in particular mid- and long ncRNAs in BP regulation.
Assuntos
Pressão Sanguínea/genética , Hipertensão/genética , RNA não Traduzido/genética , Sítios de Ligação , Pressão Sanguínea/fisiologia , Humanos , MicroRNAs/sangue , MicroRNAs/genética , MicroRNAs/urina , Polimorfismo Genético , Polimorfismo de Nucleotídeo Único , RNA Longo não Codificante/genéticaRESUMO
MicroRNAs (miRNAs) are a class of small non-coding RNAs involved in posttranscriptional regulation of gene expression, and exerting regulatory roles in plethora of biological processes. In recent years, miRNAs have received increased attention for their crucial role in health and disease, including in cardiovascular disease. This review summarizes the role of miRNAs in regulation of cardiac cell death/cell survival pathways, including apoptosis, autophagy and necrosis. It is envisaged that these miRNAs may explain the mechanisms behind the pathogenesis of many cardiac diseases, and, most importantly, may provide new avenues for therapeutic intervention that will limit cardiomyocyte cell death before it irreversibly affects cardiac function. Through an in-depth literature analysis coupled with integrative bioinformatics (pathway and synergy analysis), we dissect here the landscape of complex relationships between the apoptosis-regulating miRNAs in the context of cardiomyocyte cell death (including regulation of autophagy-apoptosis cross talk), and examine the gaps in our current understanding that will guide future investigations.
Assuntos
Apoptose , Doenças Cardiovasculares/metabolismo , MicroRNAs/metabolismo , Miócitos Cardíacos/citologia , Animais , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/fisiopatologia , Regulação da Expressão Gênica , Humanos , MicroRNAs/genética , Miócitos Cardíacos/metabolismoRESUMO
A prorenin-angiotensin system (RAS) could, via the (pro)renin receptor (ATP6AP2), have various effects in human intrauterine tissues, either directly by prorenin/ATP6AP2 cell signaling, or indirectly via angiotensin II and/or angiotensin 1-7. Here we describe RAS components in fetal membranes, decidua and placenta collected at elective cesarean section (non-laboring), after spontaneous delivery (after labor, n = 38), and in myometria (n = 16) from elective (non-laboring) or emergency cesarean (laboring) deliveries. Angiotensinogen (AGT), angiotensin-converting enzyme 1 and 2 (ACE; ACE2), angiotensin receptor 1 and 2 (AGTR1; AGTR2) and angiotensin 1-7 receptor (MAS1) mRNAs were measured by qRT-PCR and proteins were localized by immunohistochemistry. In myometrium, prorenin (REN), ATP6AP2, and downstream signaling proteins zinc finger and BTB domain-containing protein 16 (ZBTB16), transforming growth factor-ß1 (TGFß1) and prostaglandin-endoperoxide synthase 2 (PTGS2) mRNAs were also measured. RAS mRNAs, except AGTR1 and AGTR2, were abundant in decidua and lowest in amnion compared to the other tissues. ACE, AGT and PTGS2 mRNAs were higher in laboring than non-laboring myometrium, suggesting that the myometrial RAS is involved in labor. Angiotensinogen and prorenin staining in amnion, chorion and decidua was pervasive despite their mRNAs being low in amnion and chorion. In placenta, prorenin, angiotensinogen and AGTR2 were present in syncytiotrophoblasts, ACE was in fetal endothelium, while ACE2 distribution was diffuse. AGTR1 and AGTR2 mRNAs and proteins were abundant. No differences were evident in the staining patterns with labor. These results are consistent with the hypothesis that fetal vascular ACE might contribute angiotensin II to the fetus, whilst syncytial ACE2 might hypothetically have a role in converting angiotensin II to angiotensin 1-7 in maternal blood.
Assuntos
Membranas Extraembrionárias/fisiologia , Miométrio/fisiologia , Sistema Renina-Angiotensina/fisiologia , Cesárea , Feminino , Feto , Humanos , Gravidez , Proto-Oncogene Mas , RNA Mensageiro/química , RNA Mensageiro/genética , Sistema Renina-Angiotensina/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estatísticas não ParamétricasRESUMO
The T allele of the C825T polymorphism in the G-protein beta(3) subunit gene (GNB3) is related to the increase of signal transduction by the G-protein. G-proteins are intermediary paths in signal transduction from receptors involved in mood regulation and substance dependence. We studied the C825T polymorphism in individuals with (i) alcohol and nicotine dependence (n = 109), (ii) nicotine dependence only (n = 117) and (iii) non-dependent controls (n = 108). We also tested for possible associations with psychiatric comorbidities among alcohol-dependent individuals. No differences were detected for allele and genotype frequencies in individuals with or without dependencies. Alcohol-dependent individuals with the heterozygous genotype presented more frequently major depressive disorder (chi(2) = 12.34; p = 0.002). These findings, taken together with other studies suggesting an influence of the C825T polymorphism in major depressive disorder, support the hypothesis of the involvement of G-proteins in mood regulation.
Assuntos
Alcoolismo/complicações , Depressão/complicações , Depressão/genética , Proteínas Heterotriméricas de Ligação ao GTP/genética , Polimorfismo Genético , Alcoolismo/genética , Humanos , Masculino , Reação em Cadeia da Polimerase , Tabagismo/complicações , Tabagismo/genéticaRESUMO
The aim of the present study is to test for possible associations between the C-1291G polymorphism in the alpha2A-adrenergic receptor gene (ADRA2A) with tobacco smoking and alcohol dependence. The genotype and allele frequencies were compared in three groups of European-derived Brazilian males: individuals with co-occurrence of tobacco smoking and alcohol dependence (N = 110), with tobacco smoking (N = 121) and controls (N = 114). The frequency of the G allele was higher in the group with both conditions, intermediate among subjects with smoking, and lower among controls (chi(2) = 8.00; p = 0.02). The chi(2) partitioning did not reveal significant differences between the sample with the two conditions and the sample of smokers (chi(2) = 0.82; p = 0.36). Combining both groups, the difference to the non-smoking controls is higher than the one observed in the three-groups analysis (chi(2) = 7.18; p = 0.007). The results suggest a role for the ADRA2A C-1291G polymorphism, notably the G allele, in the predisposition to tobacco smoking. The influence of the ADRA2A gene in nicotine and other substance dependencies should be more extensively assessed in future studies.
Assuntos
Polimorfismo Genético/genética , Receptores Adrenérgicos alfa 2/genética , Fumar/genética , Adulto , Alcoolismo/complicações , Alcoolismo/genética , Alelos , DNA/genética , Feminino , Frequência do Gene , Testes Genéticos , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Escalas de Graduação PsiquiátricaRESUMO
The present study investigates possible associations between the 5-HTT control region polymorphism (5-HTTLPR) with adult ADHD, including subtypes, severity, temperament profile and comorbidities. The polymorphic site was genotyped in 312 adult patients with ADHD and 236 controls, all of them Brazilians of European descent. The interviews followed the DSM-IV criteria, using the K-SADS-E for ADHD and oppositional defiant disorder, SCID-I and MINI for comorbidities and the TCI for temperament dimensions. The 5-HTTLPR polymorphism was not associated with ADHD. Carriers of the S allele presented slightly higher inattention and novelty seeking scores, and a higher frequency of drug dependence. These differences do not persist after correction for multiple comparisons. These results suggest that the 5-HTTLPR polymorphism does not have a direct role in the predisposition to adult ADHD. There is suggestive evidence for a small effect in some behavioral phenotypes related to ADHD.