Epigenetic Modifications in Essential Hypertension

Hypertension and global DNA methylation: a population-based study in rural, Punjab, India

Hypertension is a significant public health concern and a modifiable risk factor for increased mortality worldwide. It is reported to be influenced by gene-environment interactions and micronutrient intake. This study aims to understand the relationship between global DNA methylation levels and hypertension, independently and in the context of micronutrient status, among rural population in Punjab, India. A total of 2300 individuals, aged 30-75 years, (54.9% females) were screened for blood pressure. Of 2300 screened individuals, 900 (age sex matched 450 cases and 450 controls of hypertension) individuals were selected to examine the relationship between hypertension, global DNA methylation (5mC), and biochemicals (Folate, Vitamin B12, and Homocysteine). Folate, vitamin B12, and homocysteine levels were estimated using chemiluminescence technique. The ELISA-based colorimetric technique was used for performing peripheral blood leucocyte (PBL) global DNA methylation (5mC). Statistical analyses were performed using SPSS version 22.0. Hypertensives were found to have significantly lower levels of global DNA methylation than normotensives (0.65 vs. 0.72 respectively; p-value = 0.01*). Individuals in the 1st quartile of 5mC were at significantly (OR: 1.671; 95% CI: 1.206-2.315; p-value = 0.01*) increased risk for hypertension in comparison to those in the 4th quartile (reference). Further hypertensives on medication with controlled blood pressure (BP) were significantly hypermethylated as compared to hypertensives on medication with uncontrolled BP (0.70 vs. 0.62 respectively; p-value = 0.04*). Folate appeared to mediate global DNA methylation among hypertensives on medication-controlled BP. Further hypertension driven hypomethylation hints towards accelerated biological aging among younger hypertensives. Hypertension may be associated with Global DNA hypomethylation in the studied rural population of Punjab, India. Folate sufficiency may prove to be an aid in improving the methylation levels among the cases of hypertension who were on medication and had controlled BP.

Genetic and Epigenetic Mechanisms Regulating Blood Pressure and Kidney Dysfunction

The pioneering work of Dr Lewis K. Dahl established a relationship between kidney, salt, and high blood pressure (BP), which led to the major genetic-based experimental model of hypertension. BP, a heritable quantitative trait affected by numerous biological and environmental stimuli, is a major cause of morbidity and mortality worldwide and is considered to be a primary modifiable factor in renal, cardiovascular, and cerebrovascular diseases. Genome-wide association studies have identified monogenic and polygenic variants affecting BP in humans. Single nucleotide polymorphisms identified in genome-wide association studies have quantified the heritability of BP and the effect of genetics on hypertensive phenotype. Changes in the transcriptional program of genes may represent consequential determinants of BP, so understanding the mechanisms of the disease process has become a priority in the field. At the molecular level, the onset of hypertension is associated with reprogramming of gene expression influenced by epigenomics. This review highlights the specific genetic variants, mutations, and epigenetic factors associated with high BP and how these mechanisms affect the regulation of hypertension and kidney dysfunction.

Renin-angiotensin system inhibitors positively impact on multiple aging regulatory pathways: Could they be used to protect against human aging?

The renin-angiotensin system (RAS)-a classical blood pressure regulator-largely contributes to healthy organ development and function. Besides, RAS activation promotes age-related changes and age-associated diseases, which are attenuated/abolished by RAS-blockade in several mammalian species. RAS-blockers also increase rodent lifespan. In previous work, we discussed how RAS-blockade downregulates mTOR and growth hormone/IGF-1 signaling, and stimulates AMPK activity (together with klotho, sirtuin, and vitamin D-receptor upregulation), and proposed that at least some of RAS-blockade's aging benefits are mediated through regulation of these intermediaries and their signaling to mitochondria. Here, we included RAS-blockade's impact on other aging regulatory pathways, that is, TGF-ß, NF-kB, PI3K, MAPK, PKC, Notch, and Wnt, all of which affect mitochondria. No direct evidence is available on RAS/RAS-blockade-aging regulatory pathway-mitochondria interactions. However, existing results allow to conjecture that RAS-blockers neutralize mitochondrial dysfunction by acting on the discussed pathways. The reviewed evidence led us to propose that the foundation is laid for conducting clinical trials aimed at testing whether angiotensin-converting enzyme inhibitors (ACEi) or angiotensin receptor blockers (ARB)-even at subclinical doses-offer the possibility to live longer and in better health. As ACEi and ARB are low cost and well-tolerated anti-hypertension therapies in use for over 35 years, investigating their administration to attenuate/prevent aging effects seems simple to implement.

A Bayesian network for estimating hypertension risk due to occupational aluminum exposure

Background

The correlation between metals and hypertension, such as sodium, zinc, potassium, and magnesium, has been confirmed, while the relationship between aluminum and hypertension is not very clear. This study aimed to evaluate the correlation between plasma aluminum and hypertension in electrolytic aluminum workers by the Bayesian networks (BN).

Methods

In 2019, 476 male workers in an aluminum factory were investigated. The plasma aluminum concentration of workers was measured by inductively coupled plasma mass spectrometry. The influencing factors on the prevalence of hypertension were analyzed by the BN.

Results

The prevalence of hypertension was 23.9% in 476 male workers. The risk of hypertension from plasma aluminum in the Q2, Q3, and Q4 groups was 5.20 (1.90-14.25), 6.92 (2.51-19.08), and 7.33 (2.69-20.01), respectively, compared with that in the Q1 group. The risk of hypertension from the duration of exposure to aluminum of >10 years was 2.23 (1.09-4.57), compared without aluminum exposure. Area under the curve was 0.80 of plasma aluminum and the duration of exposure to aluminum was based on covariates, indicating that aluminum exposure had important predictive value in the prevalence of hypertension in the occupational population. The results of the study using the BN model showed that if the plasma aluminum of all participants was higher than Q4 (≥47.86 µg/L) and the participants were drinking, smoking, diabetes, central obesity, dyslipidemia, and aged >50 years, the proportion of hypertension was 71.2%.

Conclusions

The prevalence of hypertension increased significantly with the increase of plasma aluminum level.

Epigenetics of hypertension as a risk factor for the development of coronary artery disease in type 2 diabetes mellitus

Hypertension, a multifaceted cardiovascular disorder influenced by genetic, epigenetic, and environmental factors, poses a significant risk for the development of coronary artery disease (CAD) in individuals with type 2 diabetes mellitus (T2DM). Epigenetic alterations, particularly in histone modifications, DNA methylation, and microRNAs, play a pivotal role in unraveling the complex molecular underpinnings of blood pressure regulation. This review emphasizes the crucial interplay between epigenetic attributes and hypertension, shedding light on the prominence of DNA methylation, both globally and at the gene-specific level, in essential hypertension. Additionally, histone modifications, including acetylation and methylation, emerge as essential epigenetic markers linked to hypertension. Furthermore, microRNAs exert regulatory influence on blood pressure homeostasis, targeting key genes within the aldosterone and renin-angiotensin pathways. Understanding the intricate crosstalk between genetics and epigenetics in hypertension is particularly pertinent in the context of its interaction with T2DM, where hypertension serves as a notable risk factor for the development of CAD. These findings not only contribute to the comprehensive elucidation of essential hypertension but also offer promising avenues for innovative strategies in the prevention and treatment of cardiovascular complications, especially in the context of T2DM.

Social Determinants of Health and Disparities in Hypertension and Cardiovascular Diseases

High blood pressure causes over 10 million preventable deaths annually globally. Populations in low- and middle-income countries suffer the most, experiencing increased uncontrolled blood pressure and cardiovascular disease (CVD) deaths. Despite improvements in high-income countries, disparities persist, notably in the United States, where Black individuals face up to 4× higher CVD mortality than White individuals. Social determinants of health encompass complex, multidimensional factors linked to an individual's birthplace, upbringing, activities, residence, workplaces, socioeconomic and environmental structures, and significantly affect health outcomes, including hypertension and CVD. This review explored how social determinants of health drive disparities in hypertension and related CVD morbidity from a socioecological and life course perspective. We present evidence-based strategies, emphasizing interventions tailored to specific community needs and cross-sector collaboration to address health inequalities rooted in social factors, which are key elements toward achieving the United Nations' Sustainable Development Goal 3.4 for reducing premature CVD mortality by 30% by 2030.

The importance of microvascular inflammation in ageing and age-related diseases: a position paper from the ESH working group on small arteries, section of microvascular inflammation

Microcirculation is pervasive and orchestrates a profound regulatory cross-talk with the surrounding tissue and organs. Similarly, it is one of the earliest biological systems targeted by environmental stressors and consequently involved in the development and progression of ageing and age-related disease. Microvascular dysfunction, if not targeted, leads to a steady derangement of the phenotype, which cumulates comorbidities and eventually results in a nonrescuable, very high-cardiovascular risk. Along the broad spectrum of pathologies, both shared and distinct molecular pathways and pathophysiological alteration are involved in the disruption of microvascular homeostasis, all pointing to microvascular inflammation as the putative primary culprit. This position paper explores the presence and the detrimental contribution of microvascular inflammation across the whole spectrum of chronic age-related diseases, which characterise the 21st-century healthcare landscape. The manuscript aims to strongly affirm the centrality of microvascular inflammation by recapitulating the current evidence and providing a clear synoptic view of the whole cardiometabolic derangement. Indeed, there is an urgent need for further mechanistic exploration to identify clear, very early or disease-specific molecular targets to provide an effective therapeutic strategy against the otherwise unstoppable rising prevalence of age-related diseases.

Investigation of epigenetics insights of hypertension: A bibliometric analysis

PURPOSE

Hypertension remains a major risk factor for myocardial infarction, heart failure, end-stage renal disease, and stroke. Multiple genes are involved in the process of hypertension with an additional dimension of interaction with the environment. This study conducted a bibliometric analysis of publications in the field of hypertension and epigenetics over the past 10 years to summarize the current status of the field and analyze the trends in the field.

METHODS

On February 5, 2023, we chose the web of science core collection database as the study data source. VOS viewer 1.6.18 and Cite Space 6.1.6 were used to examine publications of research on hypertension and epigenetics that were published between 2013 and 2022. We looked through the papers for journals, organizations, nations and regions, authors, and key terms.

RESULTS

This analysis covered a total of 1535 papers on studies into hypertension and epigenetics. There were 7279 authors, 83 nations, 1983 organizations, and 606 journals in all of the articles. In the USA, 540 publications were the most. The institution with the most publications was Harvard Medical School. The author with the most articles was Zhao Lubo.

CONCLUSION

This study summarizes the global research trends in hypertension and epigenetics. Publications in this field have increased year by year in the last decade and the field of research on hypertension and epigenetics has good prospects for growth.

Association between Aldosterone Synthase (CYP11B2) Gene Polymorphism and Hypertension in Pashtun Ethnic Population of Khyber Pakhtunkwha, Pakistan

Genome-wide association studies significantly increased the number of hypertension risk variants; however, most of them focused on European societies. There is lack of such studies in developing countries, including Pakistan. The lack of research studies and the high prevalence of hypertension in the Pakistani community prompted us to design this study. Aldosterone synthase (CYP11B2) was thoroughly studied in different ethnic groups; however, no such study has been conducted in the Pashtun population of Khyber Pakhtunkhwa, Pakistan. In essential hypertension, the aldosterone synthase gene (CYP11B2) plays a significant role. Aldosterone synthesis is affected by both hereditary and environmental factors. Aldosterone synthase (encoded by the CYP11B2 gene) controls the conversion of deoxycorticosterone to aldosterone and, thus, has genetic influences. Polymorphisms in the CYP11B2 gene are linked to an increased risk of hypertension. Previous research on the polymorphism of the aldosterone synthase (CYP11B2) gene and its relationship to hypertension produced inconclusive results. The present study investigates the relationship between CYP11B2 gene polymorphism and hypertension in Pakistan's Pashtun population. We used the nascent exome sequencing method to identify variants associated with hypertension. The research was divided into two phases. In phase one, DNA samples from 200 adult hypertension patients (of age ≥ 30 years) and 200 controls were pooled (n = 200/pool) and subjected to Exome Sequencing. In the second phase, the WES reported SNPs were genotyped using the Mass ARRAY technique to verify and confirm the association between WES-identified SNPs and hypertension. WES identified a total of eight genetic variants in the CYP11B2 gene. The chi-square test and logistic regression analysis were used to estimate the minor allele frequencies (MAFs) and chosen SNPs relationships with hypertension. The frequency of minor allele T was found to be higher in cases compared to the control (42% vs. 30%: p = 0.001) for rs1799998 of CYP11B2 gene, while no significant results (p > 0.05) were observed for the remaining SNPs; rs4536, rs4537, rs4545, rs4543, rs4539, rs4546 and rs6418 showed no positive association with HTN in the studied population (all p > 0.05). Our study findings suggest that rs1799998 increases susceptibly to HTN in the Pashtun population of KP, Pakistan.

Epigenetic Signatures in Arterial Hypertension: Focus on the Microvasculature

Systemic arterial hypertension (AH) is a multifaceted disease characterized by accelerated vascular aging and high cardiometabolic morbidity and mortality. Despite extensive work in the field, the pathogenesis of AH is still incompletely understood, and its treatment remains challenging. Recent evidence has shown a deep involvement of epigenetic signals in the regulation of transcriptional programs underpinning maladaptive vascular remodeling, sympathetic activation and cardiometabolic alterations, all factors predisposing to AH. After occurring, these epigenetic changes have a long-lasting effect on gene dysregulation and do not seem to be reversible upon intensive treatment or the control of cardiovascular risk factors. Among the factors involved in arterial hypertension, microvascular dysfunction plays a central role. This review will focus on the emerging role of epigenetic changes in hypertensive-related microvascular disease, including the different cell types and tissues (endothelial cells, vascular smooth muscle cells and perivascular adipose tissue) as well as the involvement of mechanical/hemodynamic factors, namely, shear stress.

Association between Interactions among ACE Gene Polymorphisms and Essential Hypertension in Patients in the Hefei Region, Anhui, China

Objective

Essential hypertension (EH) is a common cardiovascular disease that endangers human health. Its pathogenesis is complex and has not been fully elucidated. We explore the association between EH and interactions among polymorphisms of the angiotensin converting enzyme (ACE) gene in the Hefei region, Anhui, China.

Methods

A total of 500 participants (400 hypertensive and 100 normotensive) were included in this study. The polymorphisms were detected via improved multiple ligase detection reaction (iMLDR). To improve the accuracy of prediction, multifactor dimensionality reduction (MDR) was used to analyze the overall effect of interactions among seven loci on the incidence of EH.

Results

The frequencies of polymorphisms in the ACE genes rs12709426, rs4291, rs4309, rs4331, rs4343, rs4459609, and rs4461142 in the EH group were not statistically significantly different from those in the control group. We also found that the single nucleotide polymorphism (SNP) rs12709426 only had a homozygous AA genotype and no polymorphisms. There were no differences in the frequency of genetic polymorphisms between the EH and control groups. The best model explaining the EH group was the combined effect of ACE genes rs4291, rs4309, and rs4461142.

Conclusion

There is an interaction effect among ACE gene loci in EH patients in Hefei region, Anhui, China. Also, the ACE gene SNP rs12709426 only has a homozygous AA genotype and does not show an association with EH.

Summary of Known Genetic and Epigenetic Modification Contributed to Hypertension

Hypertension is a multifactorial disease due to a complex interaction among genetic, epigenetic, and environmental factors. Characterized by raised blood pressure (BP), it is responsible for more than 7 million deaths per annum by acting as a leading preventable risk factor for cardiovascular disease. Reports suggest that genetic factors are estimated to be involved in approximately 30 to 50% of BP variation, and epigenetic marks are known to contribute to the initiation of the disease by influencing gene expression. Consequently, elucidating the genetic and epigenetic mediators associated with hypertension is essential for better discernment of its pathophysiology. By deciphering the unprecedented molecular hypertension basis, it could help to unravel an individual's inclination towards hypertension which eventually could result in an arrangement of potential strategies for prevention and therapy. In the present review, we discuss known genetic and epigenetic drivers that contributed to the hypertension development and summarize the novel variants that have currently been identified. The effect of these molecular alterations on endothelial function was also presented.

The Interaction of Trauma Exposure and DNA Methylation on Blood Pressure Among Black Women in the InterGEN Study

Objective

Despite evidence that trauma exposure is linked to higher risk of hypertension, epigenetic mechanisms (such as DNA methylation) by which trauma potentially influences hypertension risk among Black adults remain understudied.

Methods

Data from a longitudinal study of Black mothers were used to test the hypothesis that direct childhood trauma (ie, personal exposure) and vicarious trauma (ie, childhood trauma experienced by their children) would interact with DNA methylation to increase blood pressure (BP). Separate linear mixed effects models were fitted at each CpG site with the DNA methylation beta-value and direct and vicarious trauma as predictors and systolic and diastolic BP modeled as dependent variables adjusted for age, cigarette smoking, and body mass index. Interaction terms between DNA methylation beta-values with direct and vicarious trauma were added.

Results

The sample included 244 Black mothers with a mean age of 31.2 years (SD = ±5.8). Approximately 45% of participants reported at least one form of direct childhood trauma and 49% reported at least one form of vicarious trauma. Epigenome-wide interaction analyses found that no CpG sites passed the epigenome-wide significance level indicating the interaction between direct or vicarious trauma with DNAm did not influence systolic or diastolic BP.

Conclusions

This is one of the first studies to simultaneously examine whether direct or vicarious exposure to trauma interact with DNAm to influence BP. Although findings were null, this study highlights directions for future research that investigates epigenetic mechanisms that may link trauma exposure with hypertension risk in Black women.

Exploring RNA modifications, editing, and splicing changes in hyperuricemia and gout

Hyperuricemia and gout are two of the most common metabolic disorders worldwide; their incidence is increasing with changes in lifestyle, and they are correlated with many diseases, including renal and cardiovascular diseases. The majority of studies on hyperuricemia and gout have focused on the discovery of the associated genes and their functions and on the roles of monocytes and neutrophils in the development of gout. Virtually no studies investigating the epigenomics of gout disease or exploring the clinical significance of such research have been conducted. In this study, we observed that the expression of enzymes involved in RNA modifications or RNA editing was affected in uric acid (UA)- or monosodium urate (MSU)-treated cell lines. RNA alternative splicing and splicing factors were also affected by UA or MSU treatment. We used transcriptome sequencing to analyze genome-wide RNA splicing and RNA editing and found significant changes in RNA splicing and RNA editing in MSU- or UA-treated THP-1 and HEK293 cells. We further found significant changes of RNA modifications, editing, and splicing in patients with gout. The data indicate that RNA modifications, editing, and splicing play roles in gout. The findings of this study may help to understand the mechanism of RNA splicing and modifications in gout, facilitating the development of new diagnostic and therapeutic strategies.

Genetic Modifications to Alter Blood Pressure Level

Genetic manipulation is one of the indispensable techniques to examine gene functions both in vitro and in vivo. In particular, cardiovascular phenotypes such as blood pressure cannot be evaluated in vitro system, necessitating the creation of transgenic or gene-targeted knock-out and knock-in experimental animals to understand the pathophysiological roles of specific genes on the disease conditions. Although genome-wide association studies (GWAS) in various human populations have identified multiple genetic variations associated with increased risk for hypertension and/or its complications, the causal links remain unresolved. Genome-editing technologies can be applied to many different types of cells and organisms for creation of knock-out/knock-in models. In the post-GWAS era, it may be more worthwhile to validate pathophysiological implications of the risk variants and/or candidate genes by creating genome-edited organisms.

The association between Alu hypomethylation and the severity of hypertension

Introduction

Epigenetic changes that cause genomic instability may be the basis of pathogenic processes of age-associated noncommunicable diseases (NCDs). Essential hypertension is one of the most common NCDs. Alu hypomethylation is an epigenetic event that is commonly found in elderly individuals. Epigenomic alterations are also found in age-associated NCDs such as osteoporosis and diabetes mellitus. Alu methylation prevents DNA from being damaged. Therefore, Alu hypomethylated DNA accumulates DNA damage and, as a result, causes organ function deterioration. Here, we report that Alu hypomethylation is a biomarker for essential hypertension.

Results

We investigated Alu methylation levels in white blood cells from normal controls, patients with prehypertension, and patients with hypertension. The hypertension group possessed the lowest Alu methylation level when classified by systolic blood pressure and diastolic blood pressure (P = 0.0002 and P = 0.0088, respectively). In the hypertension group, a higher diastolic blood pressure and a lower Alu methylation level were observed (r = -0.6278). Moreover, we found that changes in Alu hypomethylation in the four years of follow-up in the same person were directly correlated with increased diastolic blood pressure.

Conclusions

Similar to other age-associated NCDs, Alu hypomethylation is found in essential hypertension and is directly correlated with severity, particularly with diastolic blood pressure. Therefore, Alu hypomethylation may be linked with the molecular pathogenesis of high blood pressure and can be used for monitoring the clinical outcome of this disease.

A Review of Vascular Traits and Assessment Techniques, and Their Heritability

Various tools are available to assess atherosclerosis, arterial stiffening, and endothelial function. They offer utility in the assessment of hypertensive phenotypes, in cardiovascular risk prediction, and as surrogate endpoints in clinical trials. We explore the relative influence of participant genetics, with reference to large-scale genomic studies, population-based cohorts, and candidate gene studies. We find heritability estimates highest for carotid intima-media thickness (CIMT 35–65%), followed by pulse wave velocity as a measure of arterial stiffness (26–43%), and flow mediated dilatation as a surrogate for endothelial function (14–39%); data were lacking for peripheral artery tonometry. We furthermore examine genes and polymorphisms relevant to each technique. We conclude that CIMT and pulse wave velocity dominate the existing evidence base, with fewer published genomic linkages for measures of endothelial function. We finally make recommendations regarding planning and reporting of data relating to vascular assessment techniques, particularly when genomic data are also available, to facilitate integration of these tools into cardiovascular disease research.

Novel methylation mark and essential hypertension

Background

Essential hypertension (EH) is an important risk factor for various cardiovascular, cerebral and renal disorders. It is a multi-factorial trait which occurs through complex interplay between genetic, epigenetic, and environmental factors. Even after advancement of technology and deciphering the involvement of multiple signalling pathways in blood pressure regulation, it still remains as a huge global concern.

Main body of the abstract

Genome-wide association studies (GWAS) have revealed EH-associated genetic variants but these solely cannot explain the variability in blood pressure indicating the involvement of additional factors. The etiopathogenesis of hypertension has now advanced to the level of epigenomics where aberrant DNA methylation is the most defined epigenetic mechanism to be involved in gene regulation. Though role of DNA methylation in cancer and other mechanisms is deeply studied but this mechanism is in infancy in relation to hypertension. Generally, 5-methylcytosine (5mC) levels are being targeted at both individual gene and global level to find association with the disease. But recently, with advanced sequencing techniques another methylation mark, N6-methyladenine (6mA) was found and studied in humans which was earlier considered to be absent in case of eukaryotes. Relation of aberrant 6mA levels with cancer and stem cell fate has drawn attention to target 6mA levels with hypertension too.

Conclusion

Recent studies targeting hypertension has suggested 6mA levels as novel marker and its demethylase, ALKBH1 as probable therapeutic target to prevent hypertension through epigenetic programming. This review compiles different methylation studies and suggests targeting of both 5mC and 6mA levels to cover role of methylation in hypertension in broader scenario.

Expression and methylation status of BTG2, PPP1CA, and PEG3 genes in colon adenocarcinoma cell lines: promising treatment targets

Aim

This study investigated the association between methylation status and expression levels of BTG2, PPP1CA, and PEG3 genes in colon cancer.

Background

Aberrant DNA methylation is one of the most important epigenetic modifications in the development of cancer. Evidence indicates that hypermethylation of various tumor suppressor genes could be a potential mechanism of colon tumorigenesis.

Methods

The expression levels of BTG2, PPP1CA, and PEG3 genes were evaluated in HT-29/219, HCT116, SW48, SW742, SW480, and LS180 cell lines using quantitative Real-Time PCR. The methylation status of BTG2 and PPP1CA was determined by methylation-specific PCR (MSP) method, and the methylation pattern of PEG3 was evaluated by bisulfite sequencing PCR (BSP). To investigate the effect of methylation on the expression of these genes, all colon cancer cell lines were treated by 5-Azacitidine (5-Aza) and/or Trichostatin A (TSA).

Results

The expression levels of BTG2, PPP1CA, and PEG3 were highly heterogeneous and quantitatively correlated to their promoter methylation status in the studied colon cancer cell lines. Treatment by 5-Aza and/or TSA increased the expression of the above-named genes in colon cancer cell lines.

Conclusion

Overall, it seems that BTG2, PPP1CA, and PEG3 act as tumor suppressor genes in colon cancer, and methylation is a potential mechanism for their loss of expression. Therefore, these genes may be considered as suitable targets for demethylation approaches and, eventually, colon cancer treatment. Combined treatment by 5-Aza and TSA may be a promising therapeutic strategy for colon cancer treatment. Further studies may contribute to confirm these results.

Inhibition of DNMT-1 alleviates ferroptosis through NCOA4 mediated ferritinophagy during diabetes myocardial ischemia/reperfusion injury

The purpose of this study was to investigate whether inhibition of DNA (cytosine-5)-methyltransferase 1 (DNMT-1) alleviated ferroptosis through nuclear receptor coactivator 4 (NCOA4)-mediated ferritinophagy during diabetes myocardial (DM) ischemia/reperfusion (I/R) injury (IRI). Rat DM + sham (DS), I/R, and DM + I/R (DIR), H9c2 cell high glucose (HG), hypoxia reoxygenation (H/R), and high-glucose hypoxia reoxygenation (HH/R) models were established. DNMT-1 inhibitor 5-Aza-2'-deoxycytidine (5-aza-CdR) was administered to rat and cell models. The protein level of DNMT-1, NCOA4, FTH, GPX4, Beclin-1, and P62 was detected by western blotting. Compared with normal sham (NS) group, myocardial tissue was injured in DS and I/R models. The level of DNMT-1, NCOA4, and ferroptosis was increased. Moreover, the cell injury was more serious in rat DIR or HH/R model. 5-Aza-CdR could reduce NCOA4-mediated ferritinophagy and myocardial injury in DIR and HH/R models. Moreover, the siRNA for NCOA4 could also reduce the level of ferritinophagy and cell injury in HH/R model. 5-Aza-CdR enhanced the protective effect for NCOA4-siRNA in the process of cell injury. Inhibition of DNMT-1 could reduce ferroptosis during DIR, which the NCOA4-mediated ferritinophagy might be regulated.

Correlation between serum miR-122 and myocardial damage and ventricular function in patients with essential hypertension

Background

Myocardial damage and decreased ventricular function are risk factors leading to a bad prognosis in patients with essential hypertension (EH). MicroRNAs play important roles in myocardial function impairment in patients with hypertension. The purpose of our research was to investigate the correlation between serum miR-122 and myocardial damage and ventricular functions in EH patients.

Methods

The clinic data of EH patients (group A, n=60) and healthy individuals (group B, n=60) from December 2016 to December 2019 in our hospital were collected and analyzed. Serum miR-122, myocardial damage markers [B-type brain natriuretic peptide (BNP), homocysteine (Hcy), cardiac troponin T (cTnT) and creatine kinase MB isoenzyme (CK-MB)] and cardiac function indicators [ejection fraction (EF), left ventricular septal thickness (IVST), left ventricular isovolumic relaxation time (IVRT), left ventricular end-diastolic diameter (LVEDD), left ventricular posterior wall thickness (LVPWT), and left ventricular end-systolic diameter (LVESD)] were assessed in both groups. The correlation between serum miR-122 and myocardial damage markers and ventricular function indicators was analyzed.

Results

(I) The mean serum miR-122 concentration in group A and group B was 6.86±1.23 and 3.36±1.87 µmol/L, respectively. The serum miR-122 concentration in group A was evidently increased compared with that in group B. (II) The levels of BNP, Hcy, cTnT, and CK-MB in the peripheral blood in group A were evidently increased compared with those in group B (P<0.05). (III) EF and IVRT were evidently decreased in group A compared with that in group B (P<0.05). (IV) Serum miR-122 concentration was positively correlated with the myocardial damage markers BNP, Hcy, cTnT and CK-MB, and serum miR-122 concentration was negatively correlated with the ventricular function indicators EF and IVRT but not significantly correlated with other ventricular function indicators (IVST, LVEDD, LVPWT and LVESD).

Conclusions

The serum miR-122 concentration in EH patients was higher than that in healthy individuals, and miR-122 concentration was positively correlated with myocardial damage markers. Serum miR-122 level was negatively correlated with the ventricular function indicators EF and IVRT but was not significantly correlated with other ventricular function indicators (IVST, LVEDD, LVPWT, and LVESD).

Epigenetic modifications of the renin-angiotensin system in cardiometabolic diseases

Cardiometabolic diseases (CMDs) are among the most prevalent and the highest mortality diseases. Single disease etiology such as gene mutation, polymorphisms, or environmental exposure has failed to explain the origin of CMD. This can be evident in the discrepancies in disease susceptibility among individuals exposed to the same environmental insult or who acquire the same genetic variation. Epigenetics is the intertwining of genetic and environmental factors that results in diversity in the disease course, severity, and prognosis among individuals. Environmental exposures modify the epigenome and thus provide a link for translating environmental impact on changes in gene expression and precipitation to pathological conditions. Renin-angiotensin system (RAS) is comprising genes responsible for the regulation of cardiovascular, metabolic, and glycemic functions. Epigenetic modifications of RAS genes can lead to overactivity of the system, increased sympathetic activity and autonomic dysfunction ultimately contributing to the development of CMD. In this review, we describe the three common epigenetic modulations targeting RAS components and their impact on the susceptibility to cardiometabolic dysfunction. Additionally, we highlight the therapeutic efforts of targeting these epigenetic imprints to the RAS and its effects.

Arterial Hypertension: Individual Therapeutic Approaches-From DNA Sequencing to Gender Differentiation and New Therapeutic Targets

The aim of this paper is to provide an accurate overview regarding the current recommended approach for antihypertensive treatment. The importance of DNA sequencing in understanding the complex implication of genetics in hypertension could represent an important step in understanding antihypertensive treatment as well as in developing new medical strategies. Despite a pool of data from studies regarding cardiovascular risk factors emphasizing a worse prognosis for female patients rather than male patients, there are also results indicating that women are more likely to be predisposed to the use of antihypertensive medication and less likely to develop uncontrolled hypertension. Moreover, lower systolic blood pressure values are associated with increased cardiovascular risk in women compared to men. The prevalence, awareness and, most importantly, treatment of hypertension is variable in male and female patients, since the mechanisms responsible for this pathology may be different and closely related to gender factors such as the renin–angiotensin system, sympathetic nervous activity, endothelin-1, sex hormones, aldosterone, and the immune system. Thus, gender-related antihypertensive treatment individualization may be a valuable tool in improving female patients’ prognosis.

Impact of Nutritional Epigenetics in Essential Hypertension: Targeting microRNAs in the Gut-Liver Axis

PURPOSE OF REVIEW

To review the current knowledge on interactions between dietary factors and microRNAs (miRNAs) in essential hypertension (EH) pathogenesis.

RECENT FINDINGS

There exists an integration of maintenance signals generated by genetic, epigenetic, immune, and environmental (e.g., dietary) factors that work to sustain balance in the gut-liver axis. It is well established that an imbalance in this complex, intertwined system substantially increases the risk for EH. As such, pertinent research has been taken to decipher how each signal operates in isolation and together in EH progression. Recent literature indicates that both macro- and micronutrients interrupt regulatory miRNA expressions and thus, alter multiple cellular processes that contribute to EH and its comorbidities. We highlight how carbohydrates, lipids, proteins, salt, and potassium modify miRNA signatures during EH. The disruption in miRNA expression can negatively impact communication systems such as over activating the renin-angiotensin-aldosterone system, modulating the vascular smooth muscle cell phenotype, and promoting angiogenesis to favor EH. We also delineate the prognostic value of miRNAs in EH and discuss the pros and cons of surgical vs dietary prophylactic approaches in EH prevention. We propose that dietary-dependent perturbation of the miRNA profile is one mechanism within the gut-liver axis that dictates EH development.

Choline Metabolites, Hydroxybutyrate and HDL after Dietary Fiber Supplementation in Overweight/Obese Hypertensive Women: A Metabolomic Study

Metabolomics has been increasingly used to evaluate metabolic changes associated with morbidities. The objective of this study is to assess the metabolic profile before and after intervention with mixed dietary fiber in overweight and obese hypertensive women. This is an intervention study, and the sample consists of 14 women aged 28 to 58 years. An intervention with 12 g of mixed soluble and insoluble fiber is performed for a period of eight weeks. Serum metabolites are identified using a Bruker ¹H NMR spectrometer at 400 MHz. Multivariate data analysis, including principal component analysis (PCA), is used to differentiate the two groups. After supplementation with dietary fiber, there is a significant increase in the peak intensity values of the metabolites HDL-C (0.0010*), choline (0.0012*) and hydroxybutyrate (0.0010*) as well as a decrease in systolic (0.0013*) and diastolic (0.0026*) blood pressure. The analysis of the metabolomic profile allows the identification of metabolites that have been associated in the literature with hypertension and excess weight (choline, hydroxybutyrate and amino acids) and with fiber intake (choline, hydroxybutyrate and amino acids) in addition to an increase in HDL-C. The increase in the detection of the described metabolites possibly occurs due to the presence of pathologies and the use of fiber in the intervention, which also contributes to elevated HDL-c and reduced blood pressure.

MicroRNA Profiles in Normotensive and Hypertensive South African Individuals

Hypertension has a complex pathogenesis and symptoms appear in advanced disease. Dysregulation of gene expression regulatory factors like microRNAs has been reported in disease development. Identifying biomarkers which could help understand the pathogenesis and prognosis of hypertension is essential. The study's objective was to investigate microRNA expression profiles according to participant blood pressure status. Next generation sequencing was used to identify microRNAs in the whole blood of 48 body mass index-, smoking- and age-matched normotensive (n = 12), screen-detected hypertensive (n = 16) and known hypertensive (n = 20) female participants. Quantitative reverse transcription polymerase chain reaction was used to validate the next generation sequencing findings in a larger, independent sample of 84 men and 179 women. Using next generation sequencing, 30 dysregulated microRNAs were identified and miR-1299 and miR-30a-5p were the most significantly differentially expressed. Both microRNAs were upregulated in known hypertensives or screen-detected hypertensives compared to the normotensives. Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis indicated possible involvement of platelet activation, calcium signaling and aldosterone synthesis pathways. Further validation of miR-1299 and miR-30a-5p using quantitative reverse transcription polymerase chain reaction confirmed sequencing results while yielding new findings. These findings demonstrate microRNA dysregulation in hypertension and their expression may be related to genes and biological pathways essential for blood pressure homeostasis.

Mining the Selective Remodeling of DNA Methylation in Promoter Regions to Identify Robust Gene-Level Associations With Phenotype

Epigenetics is an essential biological frontier linking genetics to the environment, where DNA methylation is one of the most studied epigenetic events. In recent years, through the epigenome-wide association study (EWAS), researchers have identified thousands of phenotype-related methylation sites. However, the overlaps of identified phenotype-related DNA methylation sites between various studies are often quite small, and it might be due to the fact that methylation remodeling has a certain degree of randomness within the genome. Thus, the identification of robust gene-phenotype associations is crucial to interpreting pathogenesis. How to integrate the methylation values of different sites on the same gene and to mine the DNA methylation at the gene level remains a challenge. A recent study found that the DNA methylation difference of the gene body and promoter region has a strong correlation with gene expression. In this study, we proposed a Statistical difference of DNA Methylation between Promoter and Other Body Region (SIMPO) algorithm to extract DNA methylation values at the gene level. First, by choosing to smoke as an environmental exposure factor, our method led to significant improvements in gene overlaps (from 5 to 17%) between different datasets. In addition, the biological significance of phenotype-related genes identified by SIMPO algorithm is comparable to that of the traditional probe-based methods. Then, we selected two disease contents (e.g., insulin resistance and Parkinson's disease) to show that the biological efficiency of disease-related gene identification increased from 15.43 to 44.44% (p-value = 1.20e-28). In summary, our results declare that mining the selective remodeling of DNA methylation in promoter regions can identify robust gene-level associations with phenotype, and the characteristic remodeling of a given gene's promoter region can reflect the essence of disease.

Factors Associated with Primary Hypertension in Pediatric Patients: An Up-to-Date

BACKGROUND

Arterial hypertension in children is considered a common alteration nowadays, mainly because obesity is a growing worldwide problem closely related to increased blood pressure. Childhood hypertension can be classified as primary or secondary, depending on the etiology. Primary or essential hypertension still has its pathophysiology not fully elucidated, and there is no consensus in the literature on most underlying mechanisms. In this review, genetic and environmental factors, including sodium and potassium intake, socioeconomic status, ethnicity, family structure, obesity, sedentary lifestyle, prematurity and low birth weight, prenatal and postnatal exposures are highlighted.

OBJECTIVE

The present study aimed to perform an update on primary hypertension in childhood, providing clinicians and researchers an overview of the current state of the literature regarding the influence of genetic and environmental factors.

METHODS

This integrative review searched for articles on genetic and environmental factors related to primary hypertension in pediatric patients. The databases evaluated were PubMed and Scopus.

RESULTS

The studies have provided insights regarding many genetic and environmental factors, in addition to their association with the pathophysiology of primary hypertension in childhood. Findings corroborated the idea that primary hypertension is a multifactorial disease. Further studies in the pediatric population are needed to elucidate the underlying mechanisms.

CONCLUSION

The study of primary hypertension in pediatrics has utmost importance for the adoption of preventive measures and the development of more efficient treatments, therefore reducing childhood morbidity and the incidence of cardiovascular diseases and other health consequences later in life.

Induction of Rabies Virus Infection in Mice Brain may Up and Down Regulate Type II Interferon gamma via epigenetic modifications

As feared and deadly human diseases globally, Rabies virus contrived mechanisms to escape early immune recognition via suppression of the interferon response. This study, preliminarily investigated whether Rabies virus employs epigenetic mechanism for the suppression of the interferon using the Challenge virus standard (CVS) strain and Nigerian street Rabies virus (SRV) strain. Mice were challenged with Rabies virus (RABV) infection, and presence of RABV antigen was assessed by direct fluorescent antibody test (DFAT). A real time quantitative Polymerase chain reaction (qRT-PCR) was used to measure the expression of type II interferon gamma (IFNG) and methylation specific quantitative PCR for methylation analysis of 1FNG promoter region. Accordingly, DNA methyltransferase (DNMT) and histone acetyltransferase (HAT) enzymes activities were determined. RABV antigen was detected in all infected samples. A statistically significant increase (p < 0.05) in mRNA level of IFNG was observed at the onset of the disease and a decrease as the disease progressed. An increase in methylation in the test groups from the control group was observed, with a fluctuation in methylation as the disease progressed. DNMT and HAT activities also agree with methylation as there was an observed increase activity in test group compared with control group. Similar fluctuation pattern was observed in both CVS and SRV groups as the disease progressed with HAT, being the most active proportionally. This study suggests that epigenetic modification via DNA methylation and histone acetylation may have played a role in the expression of type II interferon gamma in Rabies virus infection. Graphical abstract.

DNA N6-methyladenine modification in hypertension

DNA methylation has a role in the pathogenesis of essential hypertension. DNA N6-methyladenine (6mA) modification as a novel adenine methylation exists in human tissues, but whether it plays a role in hypertension development remains unclear. Here, we reported that the global 6mA DNA level in leukocytes was significantly reduced in patients with hypertension and was reversed with successful treatment. Age, systolic blood pressure, and serum total cholesterol and high-density lipoprotein levels were associated with decreased leukocyte 6mA DNA level. Elevated ALKBH1 (AlkB homolog 1), a demethylase of 6mA, level mediated this dynamic change in 6mA level in leukocytes and vascular smooth muscle cells in hypertension mouse and rat models. Knockdown of ALKBH1 suppressed angiotensin II-induced vascular smooth muscle phenotype transformation, proliferation and migration. ALKBH1-6mA directly and negatively regulated hypoxia inducible factor 1 α (HIF1α), which responded to angiotensin II-induced vascular remodeling. Collectively, our results demonstrate a potential epigenetic role for ALKBH1-6mA regulation in hypertension development, diagnosis and treatment.

Histone methylation and vascular biology

The vasculature not only transports oxygenated blood, metabolites, and waste products but also serves as a conduit for hormonal communication between distant tissues. Therefore, it is important to maintain homeostasis within the vasculature. Recent studies have greatly expanded our understanding of the regulation of vasculature development and vascular-related diseases at the epigenetic level, including by protein posttranslational modifications, DNA methylation, and noncoding RNAs. Integrating epigenetic mechanisms into the pathophysiologic conceptualization of complex and multifactorial vascular-related diseases may provide promising therapeutic approaches. Several reviews have presented detailed discussions of epigenetic mechanisms not including histone methylation in vascular biology. In this review, we primarily discuss histone methylation in vascular development and maturity, and in vascular diseases.

Long noncoding RNAs as novel players in the pathogenesis of hypertension

Long noncoding RNAs (lncRNAs) are non-(protein)-coding RNAs longer than ~200 nucleotides and have been reported to be involved in multiple human diseases by regulating gene expression. A growing body of evidence has demonstrated that lncRNAs are also widely implicated in mechanisms of hypertension, including regulation of the proliferation, migration, and apoptosis of VSMCs; the production of iNOS and NO; and the angiogenic function of endothelial cells. Several lncRNAs were also differentially expressed in the renal and cardiac tissues of hypertensive rats and even in placental samples from preeclampsia patients. In particular, several circulating lncRNAs have been identified as novel biomarkers of hypertension. In this review, we summarize the current studies of lncRNAs in the pathogenesis of hypertension in order to aid in better understanding the molecular mechanism of hypertension and provide a basis to explore new therapeutic targets.

The Vasoactive Mas Receptor in Essential Hypertension

The renin–angiotensin–aldosterone system (RAAS) has been studied extensively, and with the inclusion of novel components, it has become evident that the system is much more complex than originally anticipated. According to current knowledge, there are two main axes of the RAAS, which counteract each other in terms of vascular control: The classical vasoconstrictive axis, renin/angiotensin-converting enzyme/angiotensin II/angiotensin II receptor type 1 (AT₁R), and the opposing vasorelaxant axis, angiotensin-converting enzyme 2/angiotensin-(1-7)/Mas receptor (MasR). An abnormal activity within the system constitutes a hallmark in hypertension, which is a global health problem that predisposes cardiovascular and renal morbidities. In particular, essential hypertension predominates in the hypertensive population of more than 1.3 billion humans worldwide, and yet, the pathophysiology behind this multifactorial condition needs clarification. While commonly applied pharmacological strategies target the classical axis of the RAAS, discovery of the vasoprotective effects of the opposing, vasorelaxant axis has presented encouraging experimental evidence for a new potential direction in RAAS-targeted therapy based on the G protein-coupled MasR. In addition, the endogenous MasR agonist angiotensin-(1-7), peptide analogues, and related molecules have become the subject of recent studies within this field. Nevertheless, the clinical potential of MasR remains unclear due to indications of physiological-biased activities of the RAAS and interacting signaling pathways.

Epigenetic Modifications in T Cells: The Role of DNA Methylation in Salt-Sensitive Hypertension

The SS (Dahl salt sensitive) rat is an established model of hypertension and renal damage that is accompanied with immune system activation in response to a high-salt diet. Investigations into the effects of sodium-independent and dependent components of the diet were shown to affect the disease phenotype with SS/MCW (JrHsdMcwi) rats maintained on a purified diet (AIN-76A) presenting with a more severe phenotype relative to grain-fed SS/CRL (JrHsdMcwiCrl) rats. Since contributions of the immune system, environment, and diet are documented to alter this phenotype, this present study examined the epigenetic profile of T cells isolated from the periphery and the kidney from these colonies. T cells isolated from kidneys of the 2 colonies revealed that transcriptomic and functional differences may contribute to the susceptibility of hypertension and renal damage. In response to high-salt challenge, the methylome of T cells isolated from the kidney of SS/MCW exhibit a significant increase in differentially methylated regions with a preference for hypermethylation compared with the SS/CRL kidney T cells. Circulating T cells exhibited similar methylation profiles between colonies. Utilizing transcriptomic data from T cells isolated from the same animals upon which the DNA methylation analysis was performed, a predominant negative correlation was observed between gene expression and DNA methylation in all groups. Lastly, inhibition of DNA methyltransferases blunted salt-induced hypertension and renal damage in the SS/MCW rats providing a functional role for methylation. This study demonstrated the influence of epigenetic modifications to immune cell function, highlighting the need for further investigations.

DNA Methylation of Candidate Genes (ACE II, IFN-γ, AGTR 1, CKG, ADD1, SCNN1B and TLR2) in Essential Hypertension: A Systematic Review and Quantitative Evidence Synthesis

Physical, chemical, and social environments adversely affect the molecular process and results in cell signal transduction and the subsequent transcription factor dysregulation, leading to impaired gene expression and abnormal protein synthesis. Stressful environments such as social adversity, isolation, sustained social threats, physical inactivity, and highly methylated diets predispose individuals to molecular level alterations such as aberrant epigenomic modulations that affect homeostasis and hemodynamics. With cardiovascular disease as the leading cause of mortality in the US and blacks/African Americans being disproportionately affected by hypertension (HTN) which contributes substantially to these deaths, reflecting the excess mortality and survival disadvantage of this sub-population relative to whites, understanding the molecular events, including epigenomic and socio-epigenomic modulations, is relevant to narrowing the black-white mortality risk differences. We aimed to synthesize epigenomic findings in HTN namely (a) angiotensin-converting enzyme 2 (ACE II) gene, (b) Toll-like receptor 2 (TLR2) gene, (c) interferon γ (IFN-γ) gene, and (d) Capping Actin Protein, Gelosin-Like (CAPG) gene, adducin 1(ADD1) gene, (e) Tissue inhibitor of metalloproteinase 3 (TIMP3), (f) mesoderm specific transcript (MEST) loci, (g) sodium channel epithelial 1 alpha subunit 2 (SCNN1B), (h) glucokinase (CKG) gene (i) angiotensin II receptor, type1 (AGTR1), and DNA methylation (mDNA). A systematic review and quantitative evidence synthesis (QES) was conducted using Google Scholar and PubMed with relevant search terms. Data were extracted from studies on: (a) Epigenomic modulations in HTN based on ACE II (b) TLR2, (c) IFN-γ gene, (d) CAPG, ADD1, TIMP3, MEST loci, and mDNA. The random-effect meta-analysis method was used for a pooled estimate of the common effect size, while z statistic and I^2 were used for the homogeneity of the common effect size and between studies on heterogeneity respectively. Of the 642 studies identified, five examined hypermethylation while seven studies assessed hypomethylation in association with HTN. The hypermethylation of ACE II, SCNN1B, CKG, IFN-γ gene, and miR-510 promoter were associated with hypertension, the common effect size (CES) = 6.0%, 95% CI, −0.002–11.26. In addition, the hypomethylation of TLR2, IFN-γ gene, ADD1, AGTR1, and GCK correlated with hypertension, the CES = 2.3%, 95% CI, −2.51–7.07. The aberrant epigenomic modulation of ACE II, TLR2, IFN-γ, AGTR1, and GCK correlated with essential HTN. Transforming the environments resulting from these epigenomic lesions will facilitate early intervention mapping in reducing HTN in the US population, especially among socially disadvantaged individuals, particularly racial/ethnic minorities.

Prediction of circRNAs Based on the DNA Methylation-Mediated Feature Sponge Function in Breast Cancer

Several studies have found that DNA methylation is associated with transcriptional regulation and affect sponge regulation of non-coding RNAs in cancer. The integration of circRNA, miRNA, DNA methylation and gene expression data to identify sponge circRNAs is important for revealing the role of DNA methylation-mediated regulation of sponge circRNAs in cancer progression. We established a DNA methylation-mediated circRNA crosstalk network by integrating gene expression, DNA methylation and non-coding RNA data of breast cancer in TCGA. Four modules (26 candidate circRNAs) were mined. Next, 10 DNA methylation-mediated sponge circRNAs (sp_circRNAs) and five sponge driver genes (sp_driver genes) in breast cancer were identified in the CMD network using a computational process. Among the identified genes, ERBB2 was associated with six sponge circRNAs, which illustrates its better sponge regulatory function. Survival analysis showed that DNA methylations of 10 sponge circRNA host genes are potential prognostic biomarkers in the TCGA dataset (p = 0.0239) and GSE78754 dataset (p = 0.0377). In addition, the DNA methylation of two sponge circRNA host genes showed a significant negative correlation with their driver gene expressions. We developed a strategy to predict sponge circRNAs by DNA methylation mediated with playing the role of regulating breast cancer sponge driver genes.

Stimulation of the ACE2/Ang-(1-7)/Mas axis in hypertensive pregnant rats attenuates cardiovascular dysfunction in adult male offspring

The aim of this study was to investigate whether treatment with diminazene aceturate (DIZE), a putative ACE2 activator, or with angiotensin-(1-7) during pregnancy could attenuate the development of cardiovascular dysfunction in the adult offspring of spontaneously hypertensive rats (SHRs). For this, pregnant SHRs received DIZE or Ang-(1-7) throughout gestation. The systolic blood pressure (SBP) was measured in the male offspring from the 6th to16th weeks of age by tail-cuff plethysmography. Thereafter, the left ventricular contractile function and coronary reactivity were evaluated by the Langendorff technique. Samples of the left ventricles (LVs) and kidneys were collected for histology and western blot assay in another batch of adult rat offspring. Maternal treatment with DIZE or Ang-(1-7) during pregnancy attenuated the increase in SBP in adult offspring. In addition, both DIZE and Ang-(1-7) treatments reduced the cardiomyocyte diameter and fibrosis deposition in the LV, and treatment with Ang-(1-7) also reduced the fibrosis deposition in the kidneys. Maternal treatment with DIZE, as well as Ang-(1-7), improved the coronary vasodilation induced by bradykinin in isolated hearts from adult offspring. However, no difference was observed in the contractile function of the LVs of these animals. The expression levels of AT1 and Mas receptors, ACE, ACE2, SOD, and catalase in the LV were not modified by maternal treatment with Ang-(1-7), but this treatment elicited a reduction in AT2 expression. These data show that treatment with DIZE or Ang-(1-7) during gestation promoted beneficial effects of attenuating hypertension and cardiac remodeling in adult offspring.

The gut microbiota and the brain-gut-kidney axis in hypertension and chronic kidney disease

Crosstalk between the gut microbiota and the host has attracted considerable attention owing to its involvement in diverse diseases. Chronic kidney disease (CKD) is commonly associated with hypertension and is characterized by immune dysregulation, metabolic disorder and sympathetic activation, which are all linked to gut dysbiosis and altered host-microbiota crosstalk. In this Review, we discuss the complex interplay between the brain, the gut, the microbiota and the kidney in CKD and hypertension and explain our brain-gut-kidney axis hypothesis for the pathogenesis of these diseases. Consideration of the role of the brain-gut-kidney axis in the maintenance of normal homeostasis and of dysregulation of this axis in CKD and hypertension could lead to the identification of novel therapeutic targets. In addition, the discovery of unique microbial communities and their associated metabolites and the elucidation of brain-gut-kidney signalling are likely to fill fundamental knowledge gaps leading to innovative research, clinical trials and treatments for CKD and hypertension.

A Novel Frameshift Mutation of SCNN1G Causing Liddle Syndrome with Normokalemia

BACKGROUND

Liddle syndrome (LS) is an autosomal dominant disorder caused by single-gene mutations of the epithelial sodium channel (ENaC). It is characterized by early-onset hypertension, spontaneous hypokalemia and low plasma renin and aldosterone concentrations. In this study, we reported an LS pedigree with normokalemia resulting from a novel SCNN1G frameshift mutation.

METHODS

Peripheral blood samples were collected from the proband and eight family members for DNA extraction. Next-generation sequencing and Sanger sequencing were performed to identify the SCNN1G mutation. Clinical examinations were used to comprehensively evaluate the phenotypes of two patients.

RESULTS

Genetic analysis identified a novel SCNN1G frameshift mutation, p.Arg586Valfs*598, in the proband with LS. This heterozygous frameshift mutation generated a premature stop codon and deleted the vital PY motif of ENaC. The same mutation was present in his elder brother with LS, and his mother without any LS symptoms. Biochemical examination showed normokalemia in the three mutation carriers. The mutation identified was not found in any other family members, 100 hypertensives, or 100 healthy controls.

CONCLUSIONS

Our study identified a novel SCNN1G frameshift mutation in a Chinese family with LS, expanding the genetic spectrum of SCNN1G. Genetic testing helped us identify LS with a pathogenic mutation when the genotypes and phenotype were not completely consistent because of the hypokalemia. This case emphasizes that once a proband is diagnosed with LS by genetic testing, family genetic sequencing is necessary for early diagnosis and intervention for other family members, to protect against severe cardiovascular complications.

Effects of Physical Exercise on Endothelial Function and DNA Methylation

Essential hypertension is the leading preventable cause of death in the world. Epidemiological studies have shown that physical training can reduce blood pressure (BP), both in hypertensive and healthy individuals. Increasing evidence is emerging that DNA methylation is involved in alteration of the phenotype and of vascular function in response to environmental stimuli. We evaluated repetitive element and gene-specific DNA methylation in peripheral blood leukocytes of 68 volunteers, taken before (T0) and after (T1) a three-month intervention protocol of continuative aerobic physical exercise. DNA methylation was assessed by bisulfite-PCR and pyrosequencing. Comparing T0 and T1 measurements, we found an increase in oxygen consumption at peak of exercise (VO_2peak) and a decrease in diastolic BP at rest. Exercise increased the levels of ALU and Long Interspersed Nuclear Element 1 (LINE-1) repetitive elements methylation, and of Endothelin-1 (EDN1), Inducible Nitric Oxide Synthase (NOS2), and Tumour Necrosis Factor Alpha (TNF) gene-specific methylation. VO_2peak was positively associated with methylation of ALU, EDN1, NOS2, and TNF; systolic BP at rest was inversely associated with LINE-1, EDN1, and NOS2 methylation; diastolic BP was inversely associated with EDN1 and NOS2 methylation. Our findings suggest a possible role of DNA methylation for lowering systemic BP induced by the continuative aerobic physical training program.

Circular RNAs in hypertension: challenges and clinical promise

Hypertension (HT), or high blood pressure (BP), is a chronic disease that is common among populations worldwide. The occurrence of HT is one of the leading causes of cardiovascular morbidity and mortality in adults. Although multiple studies have stressed the multifactorial and multigenic nature of HT, uncertainties about its etiology persist, and current diagnostic biomarkers can explain only a small part of the phenotypic variance of BP. Hence, the search for novel biomarkers that enable early disease prevention and guided therapy is warranted. Regulatory circRNAs have emerged as the newest player in HT-related gene networks and hold promise for improving the accuracy of diagnosis. These RNAs are genome products that are formed through back-splicing of specific regions of pre-mRNAs. Evidence suggests that these RNA species are involved in various metabolic diseases. Recent studies have revealed that aberrant expression of circRNAs is relevant to the occurrence and development of HT. Accordingly, circRNAs are proposed as a new generation of predictive biomarkers and potential therapeutic targets for different forms of HT, including pulmonary hypertension and preeclampsia. This paper presents an overview of the findings from current research focusing on the emerging role of circRNAs in the pathogenesis of hypertension. Furthermore, some of the challenges encountered by circRNA studies are highlighted, and perspectives are provided on the future of research in this area.

Preterm Birth Is Associated With Increased Blood Pressure in Young Adults: Important Opportunities for Blood Pressure Management

See Article Skudder-Hill et al.

Epigenetics and vascular diseases

Cardiovascular disease remains the number one cause of death and disability worldwide despite significant improvements in diagnosis, prevention, and early intervention efforts. There is an urgent need for improved understanding of cardiovascular processes responsible for disease development in order to develop more effective therapeutic strategies. Recent knowledge gleaned from the study of epigenetic mechanisms in the vasculature has uncovered new potential targets for intervention. Herein, we provide an overview of epigenetic mechanism, and review recent findings related to epigenetics in vascular diseases, highlighting classical epigenetic mechanism such as DNA methylation and histone modification as well as the newly discovered non-coding RNA mechanisms.

Association of circulating BMP9 with coronary heart disease and hypertension in Chinese populations

Background

Bone morphogenetic protein9 (BMP9) has been reported to have a role in vascular development. However, there is still a lack of information regarding the association between circulating BMP9 levels and cardiovascular disease in humans. The goal of this study is to measure circulating BMP9 concentrations in patients with essential hypertension (HTN), coronary heart disease (CHD) and HTN + CHD, and evaluates the relationship between circulating BMP9 and these cardiovascular diseases.

Methods

A total of 417 individuals were recruited for this cross-sectional study from June 2015 to December 2017. These subjects were screened for HTN and CHD. Circulating BMP9 concentrations were measured by ELISA.

Results

Circulating BMP9 concentrations were significantly low in HTN, CHD and HTN + CHD individuals relative to those of the healthy individuals. Circulating BMP9 correlated negatively with SBP, FIns and HOMA-_IR in HTN patients and correlated negatively with FBG and 2 h-BG in CHD patients. In both HTN and CHD patients, circulating BMP9 correlated negatively with BMI, WHR, FAT%, BP and TG. Multivariate logistic regression analysis showed that circulating BMP9 levels were associated with HTN, HTN + CHD and CHD. Individuals with low quartile of circulating BMP9 had a significantly high risk of HTN or/and CHD as compared with those in high quartile.

Conclusions

BMP9 is likely to be a biomarker for cardiovascular disease in humans, and it may play a role in the progression of cardiovascular disease.

Trial registration

ChiCTR-OPC-14005324.

Electronic supplementary material

The online version of this article (10.1186/s12872-019-1095-2) contains supplementary material, which is available to authorized users.

Epigenetic Effects of n-3 LCPUFAs: A Role in Pediatric Metabolic Syndrome

Childhood obesity represents an important public health issue worldwide and is strongly linked to metabolic alterations such as hypertension, insulin resistance, and dyslipidemia. The constellation of these conditions is commonly known as Metabolic Syndrome (MetS). Metabolic syndrome is not just a simple cluster of metabolic complications due to excess of adipose tissue, but is considered a risk factor for cardiovascular diseases. Evidence from several human and animal studies suggests that environmental and nutritional exposure during pregnancy may affect the newborn development and future health through epigenetic changes, playing a potential role in determining obesity and obesity-related complications. Understanding how nutritional epigenetic mechanisms contribute to the "transgenerational risk" for obesity and metabolic dysfunction is crucial in order to develop early prevention strategies for children's health. Nutrigenetics is the science that studies the role of nutrients in gene expression. Long Chain Polyunsaturated Fatty Acids (LCPUFAs) are known for their health benefits, especially in relation to their ability to modulate inflammation and improve some obesity-associated comorbidities, mainly by decreasing plasma triglycerides. Recent nutrigenetic research is focusing on the potential role of LCPUFAs in influencing epigenetic markers. In this review, we present the most recent updates about the possible interaction between n-3 LCPUFAs and epigenetic pathways in metabolic syndrome. Literature from MEDLINE® and the Cochrane database between May 2005 and December 2018 has been scanned.

Targeting epigenetics and non-coding RNAs in atherosclerosis: from mechanisms to therapeutics

Atherosclerosis, the principal cause of cardiovascular death worldwide, is a pathological disease characterized by fibro-proliferation, chronic inflammation, lipid accumulation, and immune disorder in the vessel wall. As the atheromatous plaques develop into advanced stage, the vulnerable plaques are prone to rupture, which causes acute cardiovascular events, including ischemic stroke and myocardial infarction. Emerging evidence has suggested that atherosclerosis is also an epigenetic disease with the interplay of multiple epigenetic mechanisms. The epigenetic basis of atherosclerosis has transformed our knowledge of epigenetics from an important biological phenomenon to a burgeoning field in cardiovascular research. Here, we provide a systematic and up-to-date overview of the current knowledge of three distinct but interrelated epigenetic processes (including DNA methylation, histone methylation/acetylation, and non-coding RNAs), in atherosclerotic plaque development and instability. Mechanistic and conceptual advances in understanding the biological roles of various epigenetic modifiers in regulating gene expression and functions of endothelial cells (vascular homeostasis, leukocyte adhesion, endothelial-mesenchymal transition, angiogenesis, and mechanotransduction), smooth muscle cells (proliferation, migration, inflammation, hypertrophy, and phenotypic switch), and macrophages (differentiation, inflammation, foam cell formation, and polarization) are discussed. The inherently dynamic nature and reversibility of epigenetic regulation, enables the possibility of epigenetic therapy by targeting epigenetic "writers", "readers", and "erasers". Several Food Drug Administration-approved small-molecule epigenetic drugs show promise in pre-clinical studies for the treatment of atherosclerosis. Finally, we discuss potential therapeutic implications and challenges for future research involving cardiovascular epigenetics, with an aim to provide a translational perspective for identifying novel biomarkers of atherosclerosis, and transforming precision cardiovascular research and disease therapy in modern era of epigenetics.