Correlation of renin angiotensin system (RAS) candidate gene polymorphisms with response to Ramipril in patients with essential hypertension

Correlation of ACE insertion/deletion gene polymorphism with captopril effectiveness in Indonesian hypertensive patients

Background: Hypertension is a prevalent health concern in Indonesia, with a high percentage of patients unresponsive to ACE inhibitor treatment. Methods: This multicenter case-control study investigated the correlation between ACE I/D and captopril effectiveness in Indonesian hypertensive patients. Hypertensive patients were divided into control (n = 69) and case (n = 73) groups. ACE I/D was identified using PCR and electrophoresis. Results: No significant differences in genotype frequencies or allele distribution were observed. The difference of blood pressure reduction among the three genotypes also lacked statistical significance. Conclusion: ACE I/D is not significantly associated with blood pressure reduction following captopril therapy in Indonesian hypertensive patients. These results underscore the limited predictive utility of ACE I/D in managing hypertension with captopril.

Management of Hypertension in the Asia-Pacific Region: A Structured Review

This article reviews available evidence regarding hypertension management in the Asia-Pacific region, focussing on five research questions that deal with specific aspects: blood pressure (BP) control, guideline recommendations, role of renin-angiotensin-aldosterone system (RAAS) inhibitors in clinical practice, pharmacological management and real-world adherence to guideline recommendations. A PubMed search identified 2537 articles, of which 94 were considered relevant. Compared with Europeans, Asians have higher systolic/diastolic/mean arterial BP, with a stronger association between BP and stroke. Calcium channel blockers are the most-commonly prescribed monotherapy in Asia, with significant variability between countries in the rates of angiotensin-converting enzyme inhibitors (ACEis)/angiotensin-receptor blockers (ARBs) and single-pill combination (SPC) use. In clinical practice, ARBs are used more commonly than ACEis, despite the absence of recommendation from guidelines and clinical evidence supporting the use of one class of drug over the other. Ideally, antihypertensive treatment should be tailored to the individual patient, but currently there are limited data on the characteristics of hypertension in Asia-Pacific individuals. Large outcome studies assessing RAAS inhibitor efficacy and safety in multi-national Asian populations are lacking. Among treated patients, BP control rates were ~ 35 to 40%; BP control in Asia-Pacific is suboptimal, and disproportionately so compared with Western nations. Strategies to improve the management of hypertension include wider access/availability of affordable treatments, particularly SPCs (which improve adherence), effective public health screening programs targeting patients to drive health-seeking behaviours, an increase in physician/patient awareness and early implementation of lifestyle changes. A unified Asia-Pacific guideline on hypertension management with pragmatic recommendations, particularly in resource-limited settings, is essential.

The clinical impact of anti-hypertensive treatment drug-gene pairs in the asian population: a systematic review of publications in the past decade

Pharmacogenetics play an important role in determining the anti-hypertensive effects of blood pressure-lowering medications and have the potential to improve future patient care. Current literature on the topic, however, has a heavy focus on Caucasians and may not be generalisable to the Asian populations. Therefore, we have conducted this systematic review to summarise and evaluate the literature of the past decade. PubMed, Embase, and the Cochrane Register of Controlled Trials were searched for relevant studies from 1 January 2011 to 23 July 2021. The outcome of interest was the response to anti-hypertensive treatment in Asians according to each genetic polymorphism. A total of 26 studies with a total of 8837 patients were included in our review, covering five classes of anti-hypertensive agents-namely, angiotensin-converting enzyme inhibitors (ACEI), angiotensin II receptor blockers (ARB), beta-blockers (BB), calcium channel blockers (CCB), and thiazide-like diuretics. Response to ACEI therapy was most susceptible to genotypic variations, while the efficacy of ARB and CCB were affected by pharmacogenetic differences to varying extent. For BB, only variations in the ADRB1 genotype significantly affects therapeutic response, while the therapeutic efficacy of thiazide-like diuretics was correlated with genotypic variations in the REN and ACE. This systematic review evaluated the impact of pharmacogenetic variations on the therapeutic efficacy of anti-hypertensive treatment in Asians and has described numerous drug-gene pairs that are potentially clinically important. Future prospective studies with larger sample sizes and longer follow-up periods are needed to better elucidate the impact of these drug-gene pairs.

Association of AGTR1 gene methylation and its genetic variant in Chinese farmer with hypertension: A case-control study

The objective was to determine the potential associations of the angiotensin II receptor type 1 (AGTR1) gene polymorphism, methylation, and lipid metabolism in Chinese farmers with hypertension. A case-control study was conducted in Wuzhi county of Henan province in China in 2013 to 2014. A total of 1034 local residents (35-74 years, 386 hypertensive cases, and 648 normotensive subjects) were enrolled in this study. Triglyceride (TG), total cholesterol (TC), high-density lipoprotein, and low-density lipoprotein were measured using automatic chemistry analyzer. The AGTR1 gene promoter methylation level was measured using quantitative methylation-specific polymerase chain reaction method. The single nucleotide polymorphism rs275653 was genotyped with TaqMan probe assay at an applied biosystems platform. The gender, body mass index (BMI), TG, TC, and family history of hypertension in the hypertension group were significantly higher than those in control group (P < .05). No significant difference was observed in the distribution of AGTR1 rs275653 polymorphism in the hypertension and controls (P > .05). The AGTR1 gene methylation in subjects carrying different genotypes was not significantly observed (P > .05). The logistic regression analysis found the AGTR1 gene methylation level was negative correlation with hypertension in the present study (odds ratio, 0.946, 95% confidence interval, 0.896-0.999) through adjusting for age, gender, BMI, education, smoking, alcohol drinking, fruit and vegetable intake, pickles intake, and family history of hypertension. The association of AGTR1 gene hypomethylation and essential hypertension was observed in Chinese farmers; no significant difference was observed in the distribution of AGTR1 rs275653 polymorphism.

Pathophysiology and potential future therapeutic targets using preclinical models of COVID-19

Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) gains entry into the lung epithelial cells by binding to the surface protein angiotensin-converting enzyme 2. Severe SARS-CoV-2 infection, also known as coronavirus disease 2019 (COVID-19), can lead to death due to acute respiratory distress syndrome mediated by inflammatory immune cells and cytokines. In this review, we discuss the molecular and biochemical bases of the interaction between SARS-CoV-2 and human cells, and in doing so we highlight knowledge gaps currently precluding development of new effective therapies. In particular, discovery of novel treatment targets in COVID-19 will start from understanding pathologic changes based on a large number of autopsy lung tissue samples. Pathogenetic roles of potential molecular targets identified in human lung tissues must be validated in established animal models. Overall, this stepwise approach will enable appropriate selection of candidate therapeutic modalities targeting SARS-CoV2 and the host inflammatory response.

Association of mononucleotide polymorphisms of angiotensinogen gene at promoter region with antihypertensive response to angiotensin receptor blockers in hypertensive Chinese

Introduction:

This study aimed to investigate whether mononucleotide polymorphisms of the angiotensinogen gene at promoter were associated with the blood-pressure-lowering response to telmisartan treatment.

Materials and methods:

After a two-week single-blind placebo run-in period, 148 patients with mild-to-moderate primary hypertension received monotherapy with 80 mg/day of telmisartan and then were followed up for eight weeks. The -6A/G and -20A/C polymorphisms of the angiotensinogen gene at promoter were determined through polymerase chain reaction and restriction fragment length polymorphsim analysis. The relationship between these polymorphisms and changes in blood pressure was observed and evaluated after eight weeks of treatment.

Results:

There were no significant differences between -6A/G, -20A/C polymorphisms of the angiotensinogen gene and blood pressure reductions after treatment, p>0.05.

Conclusion:

It is suggested that angiotensinogen-6 A/G and angiotensinogen-20 A/C polymorphisms were not associated with the antihypertensive response to telmisartan treatment in Chinese patients with hypertension.

Effect of heme oxygenase 1 and renin/prorenin receptor on oxidized low-density lipoprotein-induced human umbilical vein endothelial cells

The incidence of depression has previously been correlated to hypertension. The aim of the present study was to explore the mechanisms of depression and hypertension by examining the expression and interaction of renin/prorenin receptor (PRR) and heme oxygenase 1 (HO-1) in vascular endothelial cells. A case-control study was conducted, and general data and serum factors were compared between hypertension patients complicated with depression and patients with hypertension alone. Logistic regression analysis was used to detect risk factors associated with hypertension complicated with depression. In addition, human umbilical vein endothelial cells (HUVECs) were treated with oxidized low-density lipoprotein (ox-LDL) and/or PRR gene silencing, and a Cell Counting Kit-8 (CCK-8) assay was performed to test their proliferation. The concentrations of inflammatory factors and oxidative stress factor were also detected using enzyme-linked immunosorbent assay and chemical colorimetry. Western blot analysis and reverse transcription-quantitative polymerase chain reaction were applied to detect protein and mRNA expression levels, respectively. The results revealed that HO-1 and renin precursor (Rep) were independent factors that affected hypertension complicated with depression. Serum HO-1 levels in patients with hypertension complicated with depression were significantly lower than that in hypertensive patients without depression, while Rep levels in patients with hypertension complicated with depression were significantly higher than that in hypertensive patients without depression. In HUVECs, ox-LDL reduced the cell proliferation in a dose-dependent manner, upregulated the expression of PRR gene and downregulated the expression of HO-1 gene. It was also observed that silencing of the PRR gene promoted the expression of the HO-1 gene. Furthermore, ox-LDL upregulated the inflammatory response and oxidative stress levels, while PRR gene silencing inhibited the ox-LDL-induced inflammatory factor and oxidative stress levels in HUVECs. Thus, regulating the expression levels of HO-1 and PRR to inhibit the oxidative stress and pro-inflammatory effect of ox-LDL may provide new insight for the treatment of hypertension patients with depression.

Genetics of Human Primary Hypertension: Focus on Hormonal Mechanisms

Increasingly, primary hypertension is being considered a syndrome and not a disease, with the individual causes (diseases) having a common sign-an elevated blood pressure. To determine these causes, genetic tools are increasingly employed. This review identified 62 proposed genes. However, only 21 of them met our inclusion criteria: (i) primary hypertension, (ii) two or more supporting cohorts from different publications or within a single publication or one supporting cohort with a confirmatory genetically modified animal study, and (iii) 600 or more subjects in the primary cohort; when including our exclusion criteria: (i) meta-analyses or reviews, (ii) secondary and monogenic hypertension, (iii) only hypertensive complications, (iv) genes related to blood pressure but not hypertension per se, (v) nonsupporting studies more common than supporting ones, and (vi) studies that did not perform a Bonferroni or similar multiassessment correction. These 21 genes were organized in a four-tiered structure: distant phenotype (hypertension); intermediate phenotype [salt-sensitive (18) or salt-resistant (0)]; subintermediate phenotypes under salt-sensitive hypertension [normal renin (4), low renin (8), and unclassified renin (6)]; and proximate phenotypes (specific genetically driven hypertensive subgroup). Many proximate hypertensive phenotypes had a substantial endocrine component. In conclusion, primary hypertension is a syndrome; many proposed genes are likely to be false positives; and deep phenotyping will be required to determine the utility of genetics in the treatment of hypertension. However, to date, the positive genes are associated with nearly 50% of primary hypertensives, suggesting that in the near term precise, mechanistically driven treatment and prevention strategies for the specific primary hypertension subgroups are feasible.

Genomewide analysis of homeobox gene family in apple (Malus domestica Borkh.) and their response to abiotic stress

Homeobox proteins (HOXs) comprise a large family in eukaryotes and share a highly conserved DNA-binding motif, the homeodomain (HD). HOXs play an important role in the regulation of plant growth, development and stress response. However, systematic analysis and expression profiling of these genes have not been reported in Malus domestica. In this study, a total of 207 HOXs of M. domestica (MdHOXs) were identified and classified into 11 distinct subfamilies, and an unclassified group according to their functional domains. The MdHOXs were localized in all 17 chromosomes with various densities and a majority of them tended to formgene clusters. Analysis of the K_a/K_s ratios suggested that the duplicated genes of MdHOXs mainly underwent purifying selection with restrictive functional divergence after the duplication events. The expression of MdHOXs has organ specific characteristics and were divided into seven different groups. Stress-related cis-acting elements were prevalent in the upstream sequence of MdHOXs by systematic analysis. To explore the response to abiotic stress, eight MdHOXs were randomly selected to investigate their expression using quantitative real-time polymerase chain reaction. Transcription levels of MdHOXs were upregulated in the leaves and roots under cold, osmotic, high salinity or exogenous ABA treatments, which suggested that they may take part in the plant response to abiotic stress. These results provided basic information of HOXs in apple and will further contribute to the functional research of MdHOXs, especially the response to abiotic stress.

Angiotensin Converting Enzyme Gene Insertion/Deletion Polymorphism Is Not Responsible for Antihypertensive Therapy Induced New Onset of Type 2 Diabetes in Essential Hypertension

Background:

Antihypertensive drug therapies have been reported to be associated with new onset of type 2 diabetes mellitus in some hypertensive patients after prolonged use. Angiotensin converting enzyme (ACE) gene has been found to affect essential hypertension, response of antihypertensive therapies, and glycemic disturbances. Therefore, ACE gene I/D polymorphism may be associated with risk of new onset of type 2 diabetes via metabolic disturbances, glycemic dysregulation, and insulin resistance.

Aim:

To assess the correlation between ACE gene I/D polymorphism and glycemic disturbance under influence of diuretic and other antihypertensive drug therapies.

Materials and methods:

We recruited 270 normotensive patients as control (150 men and 120 women), 270 hypertensive patients (95 men and 175 women), and 240 hypertensive with new onset of diabetes patients (80 men and 160 women). All samples were genotyped for ACE gene polymorphic alleles and relationship between different genotypes and anthropometric and clinical parameters along with drug therapies was established and analyzed.

Results:

Baseline clinical (systolic blood pressure, diastolic blood pressure, and fasting blood glucose level) and anthropometric parameters (height, weight, waist circumference, hip circumference, waist-hip ratio, and body mass index) of study populations were found highly statistically significant (P < .05) when compared among study groups. Furthermore, genotype wise comparison of all these parameters in essential hypertensive (EH) and essential hypertensive with onset of diabetes (EHNOD) patients found most of them nonsignificant and no variation was found with respect to different genotypes of ACE gene. The genotype wise comparison of clinical parameters among different antihypertensive drug therapy was found statistically nonsignificant in both EH and EHNOD patients.

Discussion:

Anthropometric parameters can be taken as the risk indicator factors for hypertension and diabetes. However, ACE gene polymorphism may not be a risk factor for development of diabetes in hypertensive patients.

Conclusion:

The present study suggested that ACE gene polymorphism did not show any significant association with the risk of new onset of diabetes in EH patients and more detailed studies with large population size are needed.

Alpha Adducin (ADD1) Gene Polymorphism and New Onset of Diabetes Under the Influence of Selective Antihypertensive Therapy in Essential Hypertension

BACKGROUND

Different antihypertensive therapies (especially diuretics) are reported to induce the new onset of diabetes in some hypertensive patients. α-adducin-1 (ADD1) gene is salt sensitive gene which has its role in etiology of hypertension via salt sensitivity. Therefore, the G460T polymorphism of ADD1 gene may be associated with new onset of diabetes under the influence of diuretic and other antihypertensive therapies.

AIM

To assess the correlation between genetic polymorphism (ADD1 G460T polymorphism) and glycaemic disturbance under influence of diuretic and other antihypertensive drug therapies.

MATERIALS AND METHODS

We recruited study subjects, 270 normotensive as control (150 male and 120 females), 270 hypertensive patients (95 male and 175 females) and 240 hypertensive with new onset of diabetes patients (80 male and 160 females). All study samples were genotyped for ADD1 polymorphic alleles and analyzed the relationship between different genotypes with respect to anthropometric and clinical parameters along with drug therapies.

RESULTS

Clinical and anthropometric parameters (such as age, SBP, DBP, FBG, height, weight, WC, HP, W/H ratio, and BMI) of study population were found highly statistically significant (p<0.05) at base value. Further, genotype wise comparison of all the above parameters revealed most of them as non-significant (p>0.05). Whereas, comparison between genotype and different antihypertensive drug therapy of hypertensive patients, specifically, diuretic therapy as mono in male (p=0.0227) and female (p=0.0292) and in combination with BBs in both male (p=0.0023) and female (p=0.0079) revealed a higher FBG level in variant T allele. In case of hypertensive with new onset of diabetes patients, only female population showed a slightly statistically significant (p=0.0413) difference in FBG level with diuretic mono therapy. Other antihypertensive drug therapies were safe and effective either as mono or in combination therapy.

DISCUSSION

Anthropometric parameters may be the indicative factors for hypertension and diabetes. Variant T allele of ADD1 gene may be considered as the risk factor for the development of diabetes in hypertensive patients. Diuretics as mono therapy and in combination with BBs may be considered as the risk factor for new onset of diabetes in EH patients carrying variant T allele (either as TG or TT).

Genetic Variants Associated With Uncontrolled Blood Pressure on Thiazide Diuretic/β-Blocker Combination Therapy in the PEAR (Pharmacogenomic Evaluation of Antihypertensive Responses) and INVEST (International Verapamil-SR Trandolapril Study) Trials

BACKGROUND

The majority of hypertensive individuals require combination antihypertensive therapy to achieve adequate blood pressure (BP) control. This study aimed to identify genetic variants associated with uncontrolled BP on combination therapy with a thiazide diuretic and a β-blocker.

METHODS AND RESULTS

A genome-wide association study of uncontrolled BP on combination therapy was conducted among 314 white participants of the PEAR (Pharmacogenomic Evaluation of Antihypertensive Responses) trial. Multivariable logistic regression analysis was used. Genetic variants meeting a suggestive level of significance (P<1.0E-05) were tested for replication in an external cohort, INVEST (International Verapamil-SR Trandolapril study). We also examined genome-wide variant associations with systolic and diastolic BP response on combination therapy and tested for replication. We discovered a single nucleotide polymorphism, the rs261316 major allele, at chromosome 15 in the gene ALDH1A2 associated with an increased odds of having uncontrolled BP on combination therapy (odds ratio: 2.56, 95% confidence interval, 1.69-3.88, P=8.64E-06). This single nucleotide polymorphism replicated (odds ratio: 1.86, 95% confidence interval, 1.35-2.57, P=0.001) and approached genome-wide significance in the meta-analysis between discovery and replication cohorts (odds ratio: 2.16, 95% confidence interval, 1.63-2.86, P=8.60E-08). Other genes in the region surrounding rs261316 (ALDH1A2) include AQP9 and LIPC.

CONCLUSIONS

A single nucleotide polymorphism in the gene ALDH1A2 may be associated with uncontrolled BP following treatment with a thiazide diuretic/β-blocker combination.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT00246519.

DNA methylation and hypertension: emerging evidence and challenges

Hypertension is a multifactorial disease influenced by an interaction of environmental and genetic factors. The exact molecular mechanism of hypertension remains unknown. Aberrant DNA methylation is the most well-defined epigenetic modification that regulates gene transcription. However, studies on the association between DNA methylation and hypertension are still in their infancy. This review summarizes the latest evidence and challenges regarding the role of DNA methylation on hypertension.

Angiotensinogen (AGT) M235T, AGT T174M and Angiotensin-1-Converting Enzyme (ACE) I/D Gene Polymorphisms in Essential Hypertension: Effects on Ramipril Efficacy

Background:

Hypertension, one of the most important risk factors for premature cardiovascular disease, is a major worldwide public health problem. Angiotensin-1-converting enzyme (ACE) and angiotensinogen (AGT) gene polymorphisms are thought to be associated with primary hypertension. In the present study, we examined the frequency of these gene polymorphisms in an adult population with and without essential hypertension. Furthermore, we evaluated the effect of ACE and AGT gene polymorphisms on ramipril treatment efficacy in the hypertensive patients.

Methods:

A total of 166 adults (83 hypertensives and 83 normotensives) were involved in the study and genotyped for AGTM235T (rs699), AGTT174M (rs4762) and ACEI/D (rs1799752) gene polymorphisms.

Results:

The genotype and allele distribution of the AGTM235T variant significantly differed between hypertensives and normotensives [odds ratio (OR) = 1.57% (T vs M allele), 95% confidence intervals (CIs): 1.01 - 2.44; p=0.045 for hypertensives]. However, none of the 3 studied Simple Nucleotide Polymorphisms were associated with the blood pressure-lowering response to ramipril.

Conclusion:

These results suggest that AGTM235T gene polymorphism is associated with essential hypertension. However, none of the AGTM235T, AGTT174M and ACEI/D gene polymorphisms influenced ramipril effectiveness.