Polymorphisms of ACE2 gene are associated with essential hypertension and antihypertensive effects of Captopril in women

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.

Single nucleotide polymorphism-based biomarker in primary hypertension

Primary hypertension is a multiplex and multifactorial disease influenced by various strong components including genetics. Extensive research such as Genome-wide association studies and candidate gene studies have revealed various single nucleotide polymorphisms (SNPs) related to hypertension, providing insights into the genetic basis of the condition. This review summarizes the current status of SNP research in primary hypertension, including examples of hypertension-related SNPs, their location, function, and frequency in different populations. The potential clinical implications of SNP research for primary hypertension management are also discussed, including disease risk prediction, personalized medicine, mechanistic understanding, and lifestyle modifications. Furthermore, this review highlights emerging technologies and methodologies that have the potential to revolutionize the vast understanding of the basis of genetics in primary hypertension. Gene editing holds the potential to target and correct any kind of genetic mutations that contribute to the development of hypertension or modify genes involved in blood pressure regulation to prevent or treat the condition. Advances in computational biology and machine learning enable researchers to analyze large datasets and identify complex genetic interactions contributing to hypertension risk. In conclusion, SNP research in primary hypertension is rapidly evolving with emerging technologies and methodologies that have the potential to transform the knowledge about genetic basis related to the condition. These advances hold promise for personalized prevention and treatment strategies tailored to an individual's genetic profile ultimately improving patient outcomes and reducing healthcare costs.

Polymorphisms in the human angiotensin converting enzyme gene (ACE) linked to susceptibility of COVID-19 and malaria infections in the Ghanaian population

Genetic variations in the human angiotensin converting enzyme gene (ACE) influence ACE enzyme expression levels in humans and subsequently influence both communicable and non-communicable disease outcomes. More recently, polymorphisms in this gene have been linked to susceptibility and outcomes of infectious diseases such as the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and malaria infections. This study is the first to investigate the genetic diversity of ACE and ACE2 polymorphisms in the Ghanaian population. Archived filter blood blot samples from malaria patients aged ≤9 years were used. Molecular analysis for the detection of ACE rs4646994 (I/D), ACE2 rs2106809 (C/T) and rs2285666 (G/A) alleles as well as ACE2 exons 1-4 polymorphisms was conducted on 300 samples. The D allele (54%,162/300) was the most dominant polymorphism observed in the ACE rs4646994 gene whilst the G (68%, 204/300) and T alleles (59.3%,178/300) were the most frequent ACE2 rs2285666 and rs2106809 polymorphisms observed. For the 300 samples sequenced for ACE2 exons 1-4, analyses were done on 268, 282 and 137 quality sequences for exons 1, 2 and 3-4 respectively. For exon 1, the mutation D38N (2.2%; 6/268) was the most prevalent. The S19P and E37K mutations previously reported to influence COVID-19 infections were observed at low frequencies (0.4%, 1/268 each). No mutations were observed in exon 2. The N121K/T variants were the most seen in exons 3-4 at frequencies of 5.1% (K121, 7/137) and 2.9% (T121, 4/137) respectively. Most of the variants observed in the exons were novel compared to those reported in other populations in the world. This is the first study to investigate the genetic diversity of ACE and ACE2 genes in Ghanaians. The observation of novel mutations in the ACE2 gene is suggesting selection pressure. The importance of the mutations for communicable and non-communicable diseases (malaria and COVID-19) are further discussed.

Future treatments in hypertension: Can we meet the unmet needs of patients?

The prevalence of arterial hypertension is approximately 47% in the United States and 55% in Europe. Multiple different medical therapies are used to treat hypertension including diuretics, beta blockers, calcium channel blockers, angiotensin receptor blockers, angiotensin converting enzyme inhibitors, alpha blockers, central acting alpha receptor agonists, neprilysin inhibitors and vasodilators. However, despite the numerous number of medications, the prevalence of hypertension is on the rise, a considerable proportion of the hypertensive population is resistant to these therapeutic modalities and a definitive cure is not possible with the current treatment approaches. Therefore, there is a need for novel therapeutic strategies to provide better treatment and control of hypertension. In this review, our aim is to describe the latest developments in the treatment of hypertension including novel medication classes, gene therapies and RNA-based modalities.

Sexual Dimorphic Interplays Between Gut Microbiota and Antihypertensive Drugs

PURPOSE OF THE REVIEW

The purpose of this study is to review the current literature regarding gut microbiota in blood pressure regulation and its interactions with antihypertensive drugs and to discuss how sex differences in gut microbiota contribute to sexual dimorphism of hypertension and treatment.

RECENT FINDINGS

The significance of gut microbiota in blood pressure regulation and hypertension etiology is growingly recognized. Targeting the dysbiotic microbiota is proposed to be a new therapeutic method. Recently, a few studies demonstrated that the gut microbiota is highly involved in the modulation of the efficacy of antihypertensive drugs, suggesting a novel mechanism by which gut microbiota plays a role in treatment-resistant hypertension. Furthermore, studies on sex differences in gut microbiota, etiology of hypertension, and sex bias in prescription of antihypertensive medications have revealed promising avenues in sexual dimorphism-based precision medicine. However, no scientific questions are ever raised on how sex differences in gut microbiota contribute to the sex specific responses of certain classes of antihypertensive drugs. Given the dynamics and complexity among individuals, precision medicine is proposed of great potential. We review current knowledge on the interactions between gut microbiota, hypertension, and antihypertensive drugs with an emphasis on sex as a crucial determinant. We propose that sex differences in gut microbiota be a research focus to advance our understanding of hypertension management.

Pharmacogenetic association of the NR1H3 promoter variant with antihypertensive response among patients with hypertension: A longitudinal study

Background: The genetic factors in assessing therapeutic efficacy and predicting antihypertensive drug response are unclear. Therefore, this study aims to identify the associations between variants and antihypertensive drug response. Methods: A longitudinal study including 1837 hypertensive patients was conducted in Northern China and followed up for a median 2.24 years. The associations of 11 candidate variants with blood pressure changes in response to antihypertensive drugs and with the risk of cardiovascular events during the follow-up were examined. The dual-luciferase assay was carried out to assess the effect of genetic variants on gene transcriptional activity. Results: The variant rs11039149A>G in the promoter of nuclear receptor subfamily 1 group H member 3 (NR1H3) was associated with the change in systolic blood pressure (ΔSBP) in response to calcium channel blockers (CCBs) monotherapy. Patients carrying rs11039149AG genotype showed a significant increase of systolic blood pressure (SBP) at follow-up compared with AA carriers, and the difference of ΔSBP between AG and AA carriers was 5.94 mm Hg (95%CI: 2.09-9.78, p = 0.002). In 1,184 patients with CCBs therapy, SBP levels decreased in AA carriers, but increased in AG carriers, the difference of ΔSBP between AG and AA carriers was 8.04 mm Hg (95%CI: 3.28-12.81, p = 0.001). Further analysis in 359 patients with CCBs monotherapy, the difference of ΔSBP between AG and AA carriers was 15.25 mm Hg (95%CI: 6.48-24.02, p = 0.001). However, there was no significant difference in ΔSBP between AG and AA carriers with CCBs multitherapy. The rs11039149A>G was not associated with the cardiovascular events incidence during the follow-up. Additionally, transcriptional factor forkhead box C1 (FOXC1) bound to the NR1H3 promoter containing rs11039149A and significantly increased the transcriptional activity, while rs11039149 A to G change led to a loss-of-function and disabled FOXC1 binding. For the other 10 variants, associations with blood pressure changes or risk of cardiovascular events were not observed. Conclusion: Hypertensive patients with rs11039149AG genotype in the NR1H3 gene have a significant worse SBP control in response to CCBs monotherapy compared with AA carriers. Our findings suggest that the NR1H3 gene might act as a promising genetic factor to affect individual sensitivity to antihypertensive drugs.

Association investigations between ACE1 and ACE2 polymorphisms and severity of COVID-19 disease

Due to the unique affinity of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to the angiotensin-converting enzyme 2 (ACE2) receptor in patients, the foremost recent evidence indicated that ACE1 and ACE2 polymorphisms could affect the susceptibility of individuals to SARS-CoV-2 infection and also the disease outcome. Here, we aimed to assess the possible association between two polymorphisms and the severity of disease in patients. In the present study, 146 patients with COVID-19 who were admitted to the Mazandaran University of Medical Sciences hospitals between March 2020 and July 2020 were enrolled in this case-control study. The patients were divided into four groups based on clinical symptoms and severity of the diseases (mild, moderate, severe, and critical). After DNA extraction, the ACE gene I/D polymorphism (rs4646994) and ACE2 gene polymorphism (rs2285666) were genotyped using Gap-PCR and PCR-RFLP techniques, respectively. Then, five samples from each obtained genotype were confirmed by Sanger sequencing technique. Data were analyzed with SAS software version 9.1 using appropriate statistical procedures. The ACE gene I/D polymorphism (rs4646994) genotypes were classified into three types: I/I, I/D, and D/D. Our finding indicated that the prevalence of ACE1 D/D genotype was significantly higher in severe and critical COVID-19 patients (P = 0.0016). Additionally, the analysis revealed a remarkable association between rs4646994 SNP and the HB and ESRI levels in patients (P < 0.05). Although the ACE2 rs2285666 SNP was not related to the severity of disease, this variant was significantly associated with ALT, ESRI, and P. These results provide preliminary evidence of a genetic association between the ACE-D/D genotype and the D allele of ACE1 genotype and the disease severity. Therefore, our findings might be useful for identifying the susceptible population groups for COVID-19 therapy.

Systematic review and meta-analysis of human genetic variants contributing to COVID-19 susceptibility and severity

The COVID-19 pandemic has spawned global health crisis of unprecedented magnitude, claiming millions of lives and pushing healthcare systems in many countries to the brink. Among several factors that contribute to an increased risk of COVID-19 and progression to exacerbated manifestations, host genetic landscape is increasingly being recognized as a critical determinant of susceptibility/resistance to infection and a prognosticator of clinical outcomes in infected individuals. Recently, several case-control association studies investigated the influence of human gene variants on COVID-19 susceptibility and severity to identify the culpable mutations. However, a comprehensive synthesis of the recent advances in COVID-19 host genetics research was lacking, and the inconsistent findings of the association studies required reliable evaluation of the strength of association with greater statistical power. In this study, we embarked on a systematic search of all possible reports of genetic association with COVID-19 till April 07, 2022, and performed meta-analyses of all the genetic polymorphisms that were examined in at least three studies. After identifying a total of 84 studies that investigated the association of 130 polymorphisms in 61 genes, we performed meta-analyses of all the eligible studies. Seven genetic polymorphisms involving 15,550 cases and 444,007 controls were explored for association with COVID-19 susceptibility, of which, ACE1 I/D rs4646994/rs1799752, APOE rs429358, CCR5 rs333, and IFITM3 rs12252 showed increased risk of infection. Meta-analyses of 11 gene variants involving 6702 patients with severe COVID-19 and 8640 infected individuals with non-severe manifestations revealed statistically significant association of ACE2 rs2285666, ACE2 rs2106809, ACE2 rs2074192, AGTR1 rs5186, and TNFA rs1800629 with COVID-19 severity. Overall, our study presents a synthesis of evidence on all the genetic determinants implicated in COVID-19 to date, and provides evidence of correlation between the above polymorphisms with COVID-19 susceptibility and severity.

Association of ACE2 Polymorphisms and Derived Haplotypes With Obesity and Hyperlipidemia in Female Spanish Adolescents

Background

In the cardiovascular (CV) system, overactivation of the angiotensin converting enzyme (ACE) may trigger deleterious responses derived from angiotensin (Ang)-II, which can be attenuated by stimulation of ACE2 and subsequent Ang-(1-7) metabolite. However, ACE2 exhibits a high degree of genetic polymorphism that may affect its structure and stability, interfering with these cardioprotective actions. The aim of this study was to analyse the relationship of ACE2 polymorphisms with cardiovascular risk factors in children.

Methodology

Five ACE2-single nucleotide polymorphisms (SNP), rs4646188, rs2158083, rs233575, rs879922, and rs2074192, previously related to CV risk factors, were analyzed in a representative sample of 12–16-year-old children and tested for their potential association with anthropometric parameters, insulin levels and the lipid profile.

Results

Girls (N = 461) exhibited lower rates of overweight, obesity, blood pressure, and glycemia than boys (N = 412), though increased plasma lipids. The triglycerides (TG)/HDL-C ratio was, however, lower in females. Interestingly, only in girls, the occurrence of overweight/obesity was associated with the SNPs rs879922 [OR 1.67 (1.02–2.75)], rs233575 [OR 1.98 (1.21- 3.22)] and rs2158083 [OR 1.67 (1.04–2.68)]. Also, TG levels were linked to the rs879922, rs233575, and rs2158083 SNPs, and the TG/HDL-C ratio was associated with rs879922 and rs233575. Levels of TC and LDL-C were associated with rs2074192 and rs2158083. Furthermore, the established cut-off level for TG ≥ 90 mg/dL was related to rs879922 [OR 1.78 (1.06–2.96)], rs2158083 [OR 1.75 (1.08–2.82)], and rs233575 [OR 1.62 (1.00–2.61)]. The cut-off level for TC ≥ 170 mg/dL was associated with rs2074192 OR 1.54 (1.04–2.28) and rs2158083 [OR 1.53 (1.04–2.25)]. Additionally, the haplotype (C-G-C) derived from rs879922-rs2158083-rs233575 was related to higher prevalence of overweight/obesity and TG elevation.

Conclusion

The expression and activity of ACE2 may be essential for CV homeostasis. Interestingly, the ACE2-SNPs rs879922, rs233575, rs2158083 and rs2074192, and the haplotype (C-G-C) of the three former could induce vulnerability to obesity and hyperlipidemia in women. Thus, these SNPs might be used as predictive biomarkers for CV diseases and as molecular targets for CV therapy.

Evolutionary trilogy of malaria, angiotensin II and hypertension: deeper insights and the way forward

Despite clinical and pathological distinctions between malaria and hypertension, accumulated epidemiological and evolutionary evidence indicate the need of deeper understanding how severe malaria contributes to elevated hypertension risk. Malaria is said to exert strong selection pressure on the host genome, thus selecting certain genetic polymorphisms. Few candidate polymorphisms have also been reported in the RAS (ACE I/D and ACE2 rs2106809) that are shown to increase angiotensin II (ang II) levels in a combinatorial manner. The raised ang II has some antiplasmodial actions in addition to protecting against severe/cerebral malaria. It is hypothesized that RAS polymorphisms may have been naturally selected over time in the malaria-endemic areas in such a way that hypertension, or the risk thereof, is higher in such areas as compared to non-malaria endemic areas. The purpose of this review is to gain deeper insights into various sparse evidence linking malaria and hypertension and suggesting a way forward.

Evaluation of a Functional Single Nucleotide Polymorphism of the SARS-CoV-2 Receptor ACE2 That Is Potentially Involved in Long COVID

Since the occurrence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in December 2019, SARS-CoV-2 has led to a global coronavirus disease 2019 (COVID-19) pandemic. A better understanding of the SARS-CoV-2 receptor ACE2 at the genetic level would help combat COVID-19, particularly for long COVID. We performed a genetic analysis of ACE2 and searched for its common potential single nucleotide polymorphisms (SNPs) with minor allele frequency >0.05 in both European and Chinese populations that would contribute to ACE2 gene expression variation. We thought that the variation of the ACE2 expression would be an important biological feature that would strongly affect COVID-19 symptoms, such as "brain fog", which is highlighted by the fact that ACE2 acts as a major cellular receptor for SARS-CoV-2 attachment and is highly expressed in brain tissues. Based on the human GTEx gene expression database, we found rs2106809 exhibited a significant correlation with the ACE2 expression among multiple brain and artery tissues. This expression correlation was replicated in an independent European brain eQTL database, Braineac. rs2106809*G also displays significantly higher frequency in Asian populations than in Europeans and displays a protective effect (p = 0.047) against COVID-19 hospitalization when comparing hospitalized COVID-19 cases with non-hospitalized COVID-19 or SARS-CoV-2 test-negative samples with European ancestry from the UK Biobank. Furthermore, we experimentally demonstrated that rs2106809*G could upregulate the transcriptional activity of ACE2. Therefore, integrative analysis and functional experiment strongly support that ACE2 SNP rs2106809 is a functional brain eQTL and its potential involvement in long COVID, which warrants further investigation.

Baricitinib reduces 30-day mortality in older adults with moderate-to-severe COVID-19 pneumonia

BACKGROUND

Older adults are at the highest risk of severe disease and death due to COVID-19. Randomized data have shown that baricitinib improves outcomes in these patients, but focused stratified analyses of geriatric cohorts are lacking. Our objective was to analyze the efficacy of baricitinib in older adults with COVID-19 moderate-to-severe pneumonia.

METHODS

This is a propensity score [PS]-matched retrospective cohort study. Patients from the COVID-AGE and Alba-Score cohorts, hospitalized for moderate-to-severe COVID-19 pneumonia, were categorized in two age brackets of age <70 years old (86 with baricitinib and 86 PS-matched controls) or ≥70 years old (78 on baricitinib and 78 PS-matched controls). Thirty-day mortality rates were analyzed with Kaplan-Meier and Cox proportional hazard models.

RESULTS

Mean age was 79.1 for those ≥70 years and 58.9 for those <70. Exactly 29.6% were female. Treatment with baricitinib resulted in a significant reduction in death from any cause by 48% in patients aged 70 or older, an 18.5% reduction in 30-day absolute mortality risk (n/N: 16/78 [20.5%] baricitinib, 30/78 [38.5%] in PS-matched controls, p < 0.001) and a lower 30-day adjusted fatality rate (HR 0.21; 95% CI 0.09-0.47; p < 0.001). Beneficial effects on mortality were also observed in the age group <70 (8.1% reduction in 30-day absolute mortality risk; HR 0.14; 95% CI 0.03-0.64; p = 0.011).

CONCLUSIONS

Baricitinib is associated with an absolute mortality risk reduction of 18.5% in adults older than 70 years hospitalized with COVID-19 pneumonia.

New perspectives on angiotensin-converting enzyme 2 and its related diseases

Since the worldwide outbreak of coronavirus disease 2019, angiotensin-converting enzyme 2 (ACE2) has received widespread attention as the cell receptor of the severe acute respiratory syndrome coronavirus 2 virus. At the same time, as a key enzyme in the renin-angiotensin-system, ACE2 is considered to be an endogenous negative regulator of vasoconstriction, proliferation, fibrosis, and proinflammation caused by the ACE-angiotensin II-angiotensin type 1 receptor axis. ACE2 is now implicated as being closely connected to diabetes, cardiovascular, kidney, and lung diseases, and so on. This review covers the available information on the host factors regulating ACE2 and discusses its role in a variety of pathophysiological conditions in animal models and humans.

Renin-angiotensin-aldosterone system blockers and region-specific variations in COVID-19 outcomes: findings from a systematic review and meta-analysis

BACKGROUND AND AIMS

Coronavirus disease 2019 (COVID-19) has been observed to cause a high mortality in people with cardiometabolic diseases. Renin-angiotensin-aldosterone system (RAAS) blockers enhance the expression of ACE2, the binding receptor of SARS-CoV-2, and can enhance viral infectivity. We aim to provide a pooled estimate of the effect of RAAS blockers on COVID-19 outcomes.

METHODS

A literature search was performed using MEDLINE/PubMed, Google Scholar and preprint servers. All clinical studies analyzing the effect of RAAS blockers on clinical outcomes in COVID-19 patients were included in this study. Newcastle-Ottawa scale was used for quality assessment of studies. MOOSE checklist was followed. Mortality and severity outcomes were recorded as pooled odds ratio (OR) with 95% Confidence Intervals (CIs) and level of heterogeneity (I 2). Odds of mortality was the primary outcome. Odds of severity, hospitalization, intensive care unit (ICU) admission, mechanical ventilation (MV), steroid use and acute kidney injury were the secondary outcomes. Severity outcomes were chosen depending upon the definition used by respective authors. Country-specific variations and effects of individual class of RAAS blockers were also explored.

RESULTS

In total 47 published studies were included in the final analysis, with a total of 26,432 patients from 31 studies in mortality analysis and 20,127 patients from 23 studies in severity analysis. No increased risk of mortality [Pooled OR 0.91 (0.65-1.26), I 2 = 89%] or severity [Pooled OR 1.08 (0.79-1.46), I 2 = 88%] was seen with RAAS blockers. The drug class was protective in hypertension [pooled OR 0.63 (0.46-0.86), I 2 = 58%]. Severity of COVID-19 outcomes was high for Europeans [Pooled OR 2.08 (1.52-2.85), I 2 = 77%] and US patients [Pooled OR 1.87 (1.62-2.17)]. Nearly 4 times higher risk of hospitalization and 2 times higher risk of ICU admission and MV were observed in US patients. Class-wise, angiotensin receptor blocker use was associated with 1.6 times higher odds of severity, mainly in Europeans.

CONCLUSION

RAAS blockers are not associated with increased mortality in COVID-19 patients and should be continued in hypertensives. US and European patients are at higher risk of severe outcomes. Pharmacogenetic differences may explain the ethnicity-related variations.

PLAIN LANGUAGE SUMMARY

Effect of RAAS-blocking medicines on COVID-19 Background and aims: Higher deaths have been observed in COVID-19 patients who have other long-term diseases such as heart disease, diabetes, and high blood pressure. Many of these patients are prescribed a class of medicines called RAAS blockers (ramipril, telmisartan, etc). We studied whether the use of these medicines worsens the course of COVID-19 disease in these patients or causes excess deaths.Methods: We conducted a pooled analysis of 47 observational studies on the use of RAAS blocker drugs in COVID-19 patients.Results: We found that RAAS blockers do not cause excess deaths in patients with COVID-19. On the contrary, they have benefits if prescribed to those with high blood pressure. We also found that whereas European and US patients of COVID-19 taking these medicines had higher disease severity, this was not the case for Chinese patients.Conclusion: Theremay be some genetic and other factors responsible for differences by ethnicity.

Age and frailty are independently associated with increased COVID-19 mortality and increased care needs in survivors: results of an international multi-centre study

INTRODUCTION

Increased mortality has been demonstrated in older adults with coronavirus disease 2019 (COVID-19), but the effect of frailty has been unclear.

METHODS

This multi-centre cohort study involved patients aged 18 years and older hospitalised with COVID-19, using routinely collected data. We used Cox regression analysis to assess the impact of age, frailty and delirium on the risk of inpatient mortality, adjusting for sex, illness severity, inflammation and co-morbidities. We used ordinal logistic regression analysis to assess the impact of age, Clinical Frailty Scale (CFS) and delirium on risk of increased care requirements on discharge, adjusting for the same variables.

RESULTS

Data from 5,711 patients from 55 hospitals in 12 countries were included (median age 74, interquartile range [IQR] 54-83; 55.2% male). The risk of death increased independently with increasing age (>80 versus 18-49: hazard ratio [HR] 3.57, confidence interval [CI] 2.54-5.02), frailty (CFS 8 versus 1-3: HR 3.03, CI 2.29-4.00) inflammation, renal disease, cardiovascular disease and cancer, but not delirium. Age, frailty (CFS 7 versus 1-3: odds ratio 7.00, CI 5.27-9.32), delirium, dementia and mental health diagnoses were all associated with increased risk of higher care needs on discharge. The likelihood of adverse outcomes increased across all grades of CFS from 4 to 9.

CONCLUSION

Age and frailty are independently associated with adverse outcomes in COVID-19. Risk of increased care needs was also increased in survivors of COVID-19 with frailty or older age.

A comprehensive guide to the pharmacologic regulation of angiotensin converting enzyme 2 (ACE2), the SARS-CoV-2 entry receptor

The recent emergence of coronavirus disease-2019 (COVID-19) as a global pandemic has prompted scientists to address an urgent need for defining mechanisms of disease pathology and treatment. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent for COVID-19, employs angiotensin converting enzyme 2 (ACE2) as its primary target for cell surface attachment and likely entry into the host cell. Thus, understanding factors that may regulate the expression and function of ACE2 in the healthy and diseased body is critical for clinical intervention. Over 66% of all adults in the United States are currently using a prescription drug and while earlier findings have focused on possible upregulation of ACE2 expression through the use of renin angiotensin system (RAS) inhibitors, mounting evidence suggests that various other widely administered drugs used in the treatment of hypertension, heart failure, diabetes mellitus, hyperlipidemias, coagulation disorders, and pulmonary disease may also present a varied risk for COVID-19. Specifically, we summarize mechanisms on how heparin, statins, steroids and phytochemicals, besides their established therapeutic effects, may also interfere with SARS-CoV-2 viral entry into cells. We also describe evidence on the effect of several vitamins, phytochemicals, and naturally occurring compounds on ACE2 expression and activity in various tissues and disease models. This comprehensive review aims to provide a timely compendium on the potential impact of commonly prescribed drugs and pharmacologically active compounds on COVID-19 pathology and risk through regulation of ACE2 and RAS signaling.

Clinical impact of echocardiography parameters and molecular biomarkers in heart failure: Correlation of ACE2 and MCP-1 polymorphisms with echocardiography parameters: A comparative study

Heart failure is still the leading cause of hospitalization in patients over 65 years of age and is defined as a multifactorial pathology which involves environmental factors and also genetic predispositions. The aim of the present study was to evaluate a possible correlation between single nucleotide polymorphisms (SNPs) of angiotensin converting enzyme 2 (ACE2) and monocyte chemoattractant protein-1 (MCP-1) genes and cardiac remodeling in Caucasian patients diagnosed with heart failure. Our comparative translational research study included 116 patients diagnosed with heart failure and was carried out in Cluj-Napoca, Romania between September 2017 and March 2019. Three SNPs, namely rs4646156, rs4646174 and rs1024611, were genotyped using a Taqman real-time PCR technique. Our results showed that carriers of the AA genotype for ACE2 rs4646156 had a significant dilatation of the left ventricle (LV) with signs of LV hypertrophy (LVH), while TT carriers had a significant left atrial dilatation. For ACE2 rs4646174, homozygotes for the C allele presented a dilated LV with signs of LVH with statistical significance and had a tendency towards a lower ejection fraction. MCP-1 rs1024611 AA variant carriers had a significant LVH in the dominant model. In conclusion, our study showed a strong association between echocardiographic parameters of cardiac remodeling and SNPs rs4646156, rs4646174 of ACE2 and rs1024611 of MCP-1.

How Genetics Might Explain the Unusual Link Between Malaria and COVID-19

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-associated coronavirus disease 2019 (COVID-19) pandemic has been the subject of a large number of studies in recent times. Here, starting from the evidence that in Italy, the areas with the lowest number of COVID-19 cases were those with the highest incidence of malaria in the early 1900's, we explore possible inverse relationships between malaria and COVID-19. Indeed, some genetic variants, which have been demonstrated to give an advantage against malaria, can also play a role in the incidence and severity of SARS-CoV-2 infections (e.g., the ACE2 receptor). To verify this scientific hypothesis, we here use public data from whole-genome sequencing (WGS) experiments to extrapolate the genetic information of 46 world populations with matched COVID-19 data. In particular, we focus on 47 genes, including ACE2 and genes which have previously been reported to play a role in malaria. Only common variants (>5%) in at least 30% of the selected populations were considered, and, for this subset, we correlate the intra-population allele frequency with the COVID-19 data (cases/million inhabitants), eventually pinpointing meaningful variants in 6 genes. This study allows us to distinguish between positive and negative correlations, i.e., variants whose frequency significantly increases with increasing or decreasing COVID-19 cases. Finally, we discuss the possible molecular mechanisms associated with these variants and advance potential therapeutic options, which may help fight and/or prevent COVID-19.

Association between angiotensin converting enzyme gene polymorphism and essential hypertension: A systematic review and meta-analysis

Background:

The current meta-analytic study explored the relation between ACE gene insertion/deletion (I/D), and the risk of EH by reviewing relevant trials so as to determine the association between Angiotensin Converting Enzyme (ACE) gene polymorphism and essential hypertension (EH) susceptibility.

Methods:

Relevant studies published before May 2019 were collected from the PubMed, Cochrane, Embase, CNKI, VANFUN, and VIP databases.

Results:

Fifty-seven studies involving a total of 32,862 patients were included. These studies found that ACE gene D allele was associated with higher EH susceptibility in allelic model, homozygote model, dominant model, and regressive model, and that Asian population with ACE gene D allele showed a higher EH susceptibility in all these models. Moreover, ACE gene D allele was found closely related to a higher EH susceptibility in the subgroups of HWE, NO HWE, Caucasian population, and Mixed population, with the majority being males in allelic model, homozygote model, and regressive model and the majority being females in allelic model.

Conclusion:

ACE gene D allele is associated with an overall higher EH susceptibility, which is confirmed in the subgroup analysis of Asian population, HWE, NO HWE, Caucasian population, and Mixed population.

Disentangling the Coronavirus Disease 2019 Health Disparities in African Americans: Biological, Environmental, and Social Factors

The stark racial disparities related to the coronavirus disease 2019 (COVID-19) pandemic in the United States, wherein minority populations are disproportionately getting infected and succumbing to the disease, is of grave concern. It is critical to understand and address the underlying causes of these disparities that are complex and driven by interacting environmental, social and biological factors. In this article we focus on the African American community and examine how social and environmental determinants of health intersect with biological factors (comorbidities, underlying genetics, host immunity, vitamin D levels, epigenetics) to exacerbate risk for morbidity and mortality.

The Intersection between COVID-19, the Gene Family of ACE2 and Alzheimer's Disease

We reviewed factors that might influence COVID-19 outcomes (eg, neurological symptoms), including the link to Alzheimer's disease. Since the virus triggers COVID-19 infection through binding to ACE2, we focused on the ACE2 gene family, including ACE. Both ACE2 and ACE are involved in the renin-angiotensin system (RAS). In general, ACE causes inflammation and vasoconstriction, while ACE2 leads to anti-inflammation activity and vasodilation. The disturbed balance between these counter-regulatory pathways could influence susceptibility to COVID-19. Notably, dysregulation of the RAS-equilibrium contributes to Alzheimer's disease. Differences in the incidence and symptoms of COVID-19 in diverse populations could be attributed to variability in the human genome. For example, ACE and ACE2 variations could modify the outcome of COVID-19 in different populations. It would be important to conduct genome-wide studies to detect variants influencing COVID-19 presentation, with a special focus on variants affecting immune-related pathways and expression of RAS-related genes.

Pharmacogenomics of genetic polymorphism within the genes responsible for SARS-CoV-2 susceptibility and the drug-metabolising genes used in treatment

The ongoing outbreak of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) represents a significant challenge to international health. Pharmacogenomics aims to identify the different genetic variations that exist between individuals and populations in order to determine appropriate treatment protocols to enhance the efficacy of drugs and reduce their side‐effects. This literature review provides an overview of recent studies of genetic polymorphisms in genes that mediate the SARS‐CoV‐2 infection mechanism (ACE1, ACE2, TMPRSS2 and CD26). In addition, genetic variations in the drug‐metabolising enzyme genes of several selected drugs used in the treatment of COVID‐19 are summarised. This may help construct an effective health protocol based on genetic biomarkers to optimise response to treatment. Potentially, pharmacogenomics could contribute to the development of effective high‐throughput assays to improve patient evaluation, but their use will also create ethical, medical, regulatory, and legal issues, which should now be considered in the era of personalised medicine.

Allele Frequency of ACE2 Intron Variants and Its Association with Blood Pressure

Angiotensin-converting enzyme 2 (ACE2) is known as the counter-regulator of the renin-angiotensin system, it cleaves angiotensin II to render Ag 1-7, a potent vasodilator with multiple roles in cardiovascular protection. A few studies have pinpointed ACE2 polymorphisms and their relationship with heart function and hypertension in a sex-dependent manner. These observations still lack replication mostly for admixed populations. This study aimed to report minor allele frequencies of four ACE2 intron variants, rs2285666, rs2048683, rs2106809, and rs4240157, derived from previous research using the GSA, v1.0, microarray in 1231 hypertensive and nonhypertensive patients. Logistic and multiple linear regression models were developed to identify potential associations with hypertension status and systolic and diastolic blood pressure (SBP and DBP). Allele frequency differences were identified for ACE2 rs2048683 and rs4240157 in populations with European ancestry and people of the Americas. Regression analyses identified a significant association of ACE2 rs2048683 and rs4240157 with SBP/DBP in males or females. Our observations confirm sex differences in ACE2 genetic associations with SBP and DBP and contribute to the collection of genetic variation in ACE2 for admixed populations.

The Two Faces of ACE2: The Role of ACE2 Receptor and Its Polymorphisms in Hypertension and COVID-19

The mechanism for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection requires the binding of the virus to the angiotensin-converting enzyme 2 (ACE2) receptor, well-known for its role in counteracting ACE. ACE2 is involved in modulating blood pressure and establishing blood pressure homeostasis. Recently, a critical debatable question has arisen whether using antihypertensive medications will have a favorable impact on people infected with SARS-CoV-2 or a deleterious one, mainly because angiotensin-converting enzyme inhibitor (ACEI) and angiotensin-receptor blocker (ARB) therapy can modulate the expression of ACE2 protein. The concern is that the use of ACEIs and ARBs will increase the expression of ACE2 and increase patient susceptibility to viral host cell entry and propagation. On the other hand, several genetic association studies have examined the relationship between ACE2 genetic variants and the risk of developing hypertension in different ethnic populations. In this review, we discuss the ongoing arguments in the literature about ACE2's role in mortality rate among coronavirus disease 2019 (COVID-19) patients comorbid with hypertension and critically evaluate the current debate about the usage or discontinuation of ACEI/ARB antihypertensive drugs. Moreover, we explore the two opposing roles that ACE2 genetic variants might be playing in COVID-19 by reducing ACE2 receptor effectiveness and mitigating SARS-CoV-2 infectivity.

COVID-19: The Influence of ACE Genotype and ACE-I and ARBs on the Course of SARS-CoV-2 Infection in Elderly Patients

Since the beginning of 2020, the whole world has been struggling with the pandemic of Coronavirus Disease 2019 (COVID-19) caused by a novel coronavirus SARS-CoV-2. The SARS-CoV-2 infection depends on ACE2, TMPRSS2, and CD147, which are expressed on host cells. Several studies suggest that some single nucleotide polymorphisms (SNPs) of ACE2 might be a risk factor of COVID-19 infection. Genotypes affect ACE2 structure, its serum concentration, and levels of circulating angiotensin (1-7). Moreover, there is evidence that ACE genotype affects the outcomes of acute respiratory distress syndrome (ARDS) treatment, the most severe consequence of SARS-CoV-2 infection. COVID-19 morbidity, infection course, and mortality might depend on ACE D allele frequency. The aim of this narrative review was to analyze and identify the mechanisms of ACE-I and ARBs with particular emphasis on angiotensin receptors and their polymorphism in the light of COVID-19 pandemic as these medications are commonly prescribed to elderly patients. There is no direct evidence yet for ACE-I or ARBs in the treatment of COVID-19. However, for those already taking these medications, both the European Society of Cardiology and the American College of Cardiology recommend continuing the treatment, because at present, there is no clear clinical or scientific evidence to justify the discontinuation of ACE-I or ARBs. Individualized treatment decisions should be based on the clinical condition and co-morbidities of each patient.

ACE2 as a Therapeutic Target for COVID-19; its Role in Infectious Processes and Regulation by Modulators of the RAAS System

Angiotensin converting enzyme 2 (ACE2) is the recognized host cell receptor responsiblefor mediating infection by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). ACE2bound to tissue facilitates infectivity of SARS-CoV-2; thus, one could argue that decreasing ACE2tissue expression would be beneficial. However, ACE2 catalytic activity towards angiotensin I (AngI) and II (Ang II) mitigates deleterious effects associated with activation of the renin-angiotensinaldosteronesystem (RAAS) on several organs, including a pro-inflammatory status. At the tissuelevel, SARS-CoV-2 (a) binds to ACE2, leading to its internalization, and (b) favors ACE2 cleavage toform soluble ACE2: these actions result in decreased ACE2 tissue levels. Preserving tissue ACE2activity while preventing ACE2 shredding is expected to circumvent unrestrained inflammatoryresponse. Concerns have been raised around RAAS modulators and their effects on ACE2expression or catalytic activity. Various cellular and animal models report conflicting results invarious tissues. However, recent data from observational and meta-analysis studies in SARS-CoV-2-infected patients have concluded that RAAS modulators do not increase plasma ACE2 levels orsusceptibility to infection and are not associated with more severe diseases. This review presentsour current but evolving knowledge of the complex interplay between SARS-CoV-2 infection, ACE2levels, modulators of RAAS activity and the effects of RAAS modulators on ACE2 expression.

Angiotensin converting enzyme: A review on expression profile and its association with human disorders with special focus on SARS-CoV-2 infection

Angiotensin-converting enzyme (ACE) and its homologue, ACE2, have been mostly associated with hypertensive disorder. However, recent pandemia of SARS-CoV-2 has put these proteins at the center of attention, as this virus has been shown to exploit ACE2 protein to enter cells. Clear difference in the response of affected patients to this virus has urged researchers to find the molecular basis and pathophysiology of the cell response to this virus. Different levels of expression and function of ACE proteins, underlying disorders, consumption of certain medications and the existence of certain genomic variants within ACE genes are possible explanations for the observed difference in the response of individuals to the SARS-CoV-2 infection. In the current review, we discuss the putative mechanisms for this observation.

SARS-CoV-2 pandemic and research gaps: Understanding SARS-CoV-2 interaction with the ACE2 receptor and implications for therapy

The COVID-19 pandemic is an emerging threat to global public health. While our current understanding of COVID-19 pathogenesis is limited, a better understanding will help us develop efficacious treatment and prevention strategies for COVID-19. One potential therapeutic target is angiotensin converting enzyme 2 (ACE2). ACE2 primarily catalyzes the conversion of angiotensin I (Ang I) to a nonapeptide angiotensin or the conversion of angiotensin II (Ang II) to angiotensin 1-7 (Ang 1-7) and has direct effects on cardiac function and multiple organs via counter-regulation of the renin-angiotensin system (RAS). Significant to COVID-19, ACE2 is postulated to serve as a major entry receptor for SARS-CoV-2 in human cells, as it does for SARS-CoV. Many infected individuals develop COVID-19 with fever, cough, and shortness of breath that can progress to pneumonia. Disease progression promotes the activation of immune cells, platelets, and coagulation pathways that can lead to multiple organ failure and death. ACE2 is expressed by epithelial cells of the lungs at high level, a major target of the disease, as seen in post-mortem lung tissue of patients who died with COVID-19, which reveals diffuse alveolar damage with cellular fibromyxoid exudates bilaterally. Comparatively, ACE2 is expressed at low level by vascular endothelial cells of the heart and kidney but may also be targeted by the virus in severe COVID-19 cases. Interestingly, SARS-CoV-2 infection downregulates ACE2 expression, which may also play a critical pathogenic role in COVID-19. Importantly, targeting ACE2/Ang 1-7 axis and blocking ACE2 interaction with the S protein of SARS-CoV-2 to curtail SARS-CoV-2 infection are becoming very attractive therapeutics potential for treatment and prevention of COVID-19. Here, we will discuss the following subtopics: 1) ACE2 as a receptor of SARS-CoV-2; 2) clinical and pathological features of COVID-19; 3) role of ACE2 in the infection and pathogenesis of SARS; 4) potential pathogenic role of ACE2 in COVID-19; 5) animal models for pathological studies and therapeutics; and 6) therapeutics development for COVID-19.

Potential mechanisms of hemorrhagic stroke in elderly COVID-19 patients

The novel severe acute respiratory syndrome coronavirus 2 is the causative agent of coronavirus disease 2019, a new human infectious disease. While fever, cough, and respiratory distress are typical first symptoms, a fraction of those affected present instead with neurological symptoms suggestive of central nervous system compromise. This review summarizes the potential contribution of coronavirus disease 2019 to hemorrhagic stroke in the elderly and proposes possible mechanisms. Reports show that the most affected patients have underlying chronic diseases such as hypertension and diabetes, which are two key risk factors for hemorrhagic stroke. Angiotensin-converting enzyme 2 is the main host cell surface receptor interacting with the severe acute respiratory syndrome coronavirus 2 spike glycoprotein to allow viral entry and infection. We speculate that ensuing downregulation of angiotensin-converting enzyme 2 expression may compound the risk conferred by pre-existing comorbidities and critically influence the pathogenesis of hemorrhagic stroke by elevating blood pressure and impairing cerebrovascular endothelial function. Additionally, both age- and/or disease-related immune dysfunction and enhanced catecholamine release secondary to anxiety and stress may also aggravate central nervous system symptoms of severe acute respiratory syndrome coronavirus 2 infection. Thus, assessment of systemic inflammatory biomarkers and tight control of hemodynamic parameters upon admission are crucial to minimize mortality and morbidity in coronavirus disease 2019 patients with central nervous system symptoms suggestive of incipient stroke.

Why does COVID-19 disproportionately affect older people?

The severity and outcome of coronavirus disease 2019 (COVID-19) largely depends on a patient's age. Adults over 65 years of age represent 80% of hospitalizations and have a 23-fold greater risk of death than those under 65. In the clinic, COVID-19 patients most commonly present with fever, cough and dyspnea, and from there the disease can progress to acute respiratory distress syndrome, lung consolidation, cytokine release syndrome, endotheliitis, coagulopathy, multiple organ failure and death. Comorbidities such as cardiovascular disease, diabetes and obesity increase the chances of fatal disease, but they alone do not explain why age is an independent risk factor. Here, we present the molecular differences between young, middle-aged and older people that may explain why COVID-19 is a mild illness in some but life-threatening in others. We also discuss several biological age clocks that could be used in conjunction with genetic tests to identify both the mechanisms of the disease and individuals most at risk. Finally, based on these mechanisms, we discuss treatments that could increase the survival of older people, not simply by inhibiting the virus, but by restoring patients' ability to clear the infection and effectively regulate immune responses.

Biological plausibility for interactions between dietary fat, resveratrol, ACE2, and SARS-CoV illness severity

The angiotensin converting enzyme-2 (ACE2) cellular receptor is responsible for the pathogenesis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), thus impacting the entrance and clearance of the virus. Studies demonstrate that upregulation of ACE2 has a protective effect on SARS-CoV-2 illness severity. Moreover, animal studies demonstrate that dietary intake can modulate ACE2 gene expression and function. A high intake of resveratrol may have a protective role, upregulating ACE2, whereas a high intake of dietary fat may have a detrimental role, downregulating ACE2. As such, we postulate on the biological plausibility of interactions between dietary fat and/or resveratrol and ACE2 gene variations in the modulation of SARS-CoV-2 illness severity. We call to action the research community to test this plausible interaction in a sample of human subjects.

Hypertension and hypertensive left ventricular hypertrophy are associated with ACE2 genetic polymorphism

AIMS

Renin-angiotensin system modulates cardiac structure independent of blood pressure. The present study aimed at investigating whether single nucleotide polymorphism (SNP) and haplotype of angiotensin converting enzyme 2 (ACE2) could influence blood pressure and the susceptibility to hypertensive left ventricular hypertrophy (LVH).

SUBJECTS AND METHODS

A total of 647 patients (347 females and 300 males) with newly diagnosed mild to moderate essential hypertension were enrolled in a blood pressure matched, case-control study. Four ACE2 tagSNPs (rs2074192, rs4646176, rs4646155 and rs2106809) were genotyped and major haplotypes consisting of these four SNPs were reconstructed for all subjects.

KEY FINDINGS

In females, minor alleles of ACE2 rs2074192 and rs2106809 respectively conferred a 2.1 and 2.0 fold risk for LVH. ACE2 haplotype TCGT increased the risk for LVH while another haplotype CCGC decreased the risk in females. The covariates-adjusted mean left ventricular mass index was 11% greater in TCGT haplotype carriers than in noncarriers in women. In females, the covariates-adjusted mean systolic blood pressure was 3.4 mm Hg lower in CCGC haplotype carriers than in noncarriers. In males, the covariates-adjusted mean systolic blood pressure was 2.4 mm Hg lower in CCGC haplotype carriers than in noncarriers.

SIGNIFICANCE

ACE2 tagSNPs rs2074192 and rs2106809 as well as major haplotypes CCGC and TCGT may serve as novel risk markers for LVH in hypertensive patients.

Association of angiotensin-converting enzyme 2 gene polymorphism and enzymatic activity with essential hypertension in different gender: A case-control study

Angiotensin-converting enzyme 2 (ACE2) plays an important role in the development of essential hypertension (EH). The aim of this study was to investigate the relationship of ACE2 gene polymorphisms and enzymatic activity with EH in the northeastern Chinese Han population. 34 single-nucleotide polymorphism (SNP) loci of ACE2 were detected in 1024 EH patients and 956 normotensive (NT) controls by Sequenom Mass-ARRAY RS1000. Five SNPs (rs1514283, rs4646155, rs4646176, rs2285666, and rs879922) in ACE2 gene were determined to significantly associate with EH in female participants, while no SNP locus was linked to male group. Specifically, it was the first time to report that rs4646155 was significantly associated with EH in females. Furthermore, the correlation between ACE2 activity and clinical parameters were performed by Pearson correlation analysis in EH patients. We found that the ACE2 activity level was negatively correlated with body mass index (BMI), DBP, and pulse pressure, and significantly positively with ACE2 concentration, blood glucose and estrogen level in female EH patients. These results demonstrated that the genetic variants of ACE2 played vital roles in the development of EH. And the serum ACE2 activity can predict the development of cardiac dysfunction in EH patients.

The Association Between ACE2 Gene Polymorphism and the Stroke Recurrence in Chinese Population

OBJECTIVES

The angiotensin-converting enzyme 2 (ACE2) is closely associated with cardiovascular disease and cerebrovascular disease. Most studies on ACE2 gene polymorphism focused on its relations with cardiovascular disease, but there was a lack of research on its relations with stroke. Our study aimed to explore the association between 4 single-nucleotidepolymorphisms (SNPs) of ACE2 gene polymorphism and stroke recurrence.

DESIGN AND PARTICIPANTS

In our study, the case group included 125 stroke patients with recurrence and the control group included 153 patients without recurrence. Four SNPs (rs2106809, rs2285666, rs879922, and rs2074192) were genotyped by Ligase detection reaction. The association between stroke recurrence and SNPs were analyzed by multivariate logistic regression.

RESULTS

We find no association between ACE2 gene polymorphism and stroke recurrence. Haplotype A-G-C may associate with the stoke recurrence of male patients. The recurrence risk of male stroke patients with hypertension history and rs2285666-C allele is 2.82 times as high as that of those without hypertension history but with T allele. Among male stroke patients with hypertension history, the recurrence risk of those with rs2285666-C allele is 2.38 times as high as those with T allele; and the recurrence risk of those with rs2106809-A allele is 2.12 times as high as those with G allele. But those recurrence risks lose their statistical significance after adjustment for other factors.

CONCLUSIONS

We find no influence of ACE2 gene polymorphism on stroke recurrence and only find possible interaction between hypertension history and the ACE2 gene in male stroke patients.

Relationship between genetic variants of ACE2 gene and circulating levels of ACE2 and its metabolites

WHAT IS KNOWN

Angiotensin-converting enzyme 2 (ACE2) plays an important role in the development of essential hypertension (EH). Genetic factors remarkably influence circulating ACE2 level.

OBJECTIVE

Because heritability had remarkable effects on circulating ACE2, we designed this study to shed light on whether circulating levels of ACE2, angiotensin-(1-7) and angiotensin-(1-9) were linked to single nucleotide polymorphisms (SNPs) and haplotypes in ACE2 gene.

METHODS

A total of 213 patients with newly diagnosed mild to moderate EH were enrolled in the present study. Four ACE2 tag SNPs (rs2074192, rs4646171, rs4646155 and rs2106809) were genotyped, and major haplotypes consisting of these 4 SNPs were reconstructed for all subjects. Circulating levels of ACE2, angiotensin-(1-7) and angiotensin-(1-9) were measured using enzyme-linked immunosorbent assay.

RESULTS

In female subjects, linear regression analysis suggested that rare alleles of ACE2 rs2074192 and rs2106809 were associated with reduced circulating angiotensin-(1-7) levels (P=.007 and P=.006, respectively). ACE2 haplotype CAGC was associated with elevated circulating angiotensin-(1-7) levels (P=.03) whereas TAGT was associated with reduced circulating angiotensin-(1-7) levels in females (P<.001). Univariate linear regression analysis revealed that circulating ACE2 levels were positively associated with systolic blood pressure (P=.02), mean arterial pressure (P=.02) and serum creatinine (P<.001) in females whereas circulating ACE2 levels were positively associated with age (P<.001) and serum creatinine (P<.001) in males.

WHAT IS NEW AND CONCLUSION

ACE2 SNPs and haplotypes are associated with circulating angiotensin-(1-7) levels. ACE2 genetic variants may be the determinants of circulating angiotensin-(1-7) levels in hypertensive females.

En route to precision medicine through the integration of biological sex into pharmacogenomics

Frequently, pharmacomechanisms are not fully elucidated. Therefore, drug use is linked to an elevated interindividual diversity of effects, whether therapeutic or adverse, and the role of biological sex has as yet unrecognized and underestimated consequences. A pharmacogenomic approach could contribute towards the development of an adapted therapy for each male and female patient, considering also other fundamental features, such as age and ethnicity. This would represent a crucial step towards precision medicine and could be translated into clinical routine. In the present review, we consider recent results from pharmacogenomics and the role of sex in studies that are relevant to cardiovascular therapy. We focus on genome-wide analyses, because they have obvious advantages compared with targeted single-candidate gene studies. For instance, genome-wide approaches do not necessarily depend on prior knowledge of precise molecular mechanisms of drug action. Such studies can lead to findings that can be classified into three categories: first, effects occurring in the pharmacokinetic properties of the drug, e.g. through metabolic and transporter differences; second, a pharmacodynamic or drug target-related effect; and last diverse adverse effects. We conclude that the interaction of sex with genetic determinants of drug response has barely been tested in large, unbiased, pharmacogenomic studies. We put forward the theory that, to contribute towards the realization of precision medicine, it will be necessary to incorporate sex into pharmacogenomics.

Impact of ACE2 gene polymorphism on antihypertensive efficacy of ACE inhibitors

Angiotensin-converting enzyme 2 (ACE2), a newly discovered member of renin-angiotensin-aldosterone system, counterbalances the actions of angiotensin-converting enzyme. The objective of our study was to assess the association between rs2106809 polymorphism in ACE2 gene and the blood pressure response to ACE inhibitors in untreated hypertensive patients. After a 2-week, double-blind placebo run-in period, either benazepril or imidapril was administered for 6 weeks to 497 patients with mild to moderate essential hypertension. The achieved changes in BP were analyzed for their association with genotypes at ACE2 gene loci. In female hypertensive patients, the genotype frequency of ACE2 rs2106809 was 36.7%, 45.2% and 18.1% for CC, CT and TT genotypes, respectively. After 6 weeks of treatment, the reductions in diastolic blood pressure were significantly greater in female patients carrying the CC or CT genotype compared with those carrying the TT genotype (9.62±6.83 or 10.2±7.2 versus 6.81±6.31 mm Hg, respectively; P=0.045, analysis of variance (ANOVA)). Moreover, the reductions in mean arterial pressure were significantly greater in female patients carrying the CC or CT genotype compared with those carrying the TT genotype (12.1±7.5 or 12.0±7.9 versus 8.38±6.83 mm Hg, respectively; P=0.035, ANOVA). In male hypertensive patients, the genotype frequency of ACE2 rs2106809 was 58.1% and 41.9% for C and T genotypes, respectively. However, no association could be observed in males. We conclude that ACE2 rs2106809 is an important predictive factor of the response to antihypertensive treatment with ACE inhibitors in Chinese female hypertensive patients.

The High Blood Pressure-Malaria Protection Hypothesis

RATIONALE

A recently proposed hypothesis states that malaria may contribute to hypertension in endemic areas,¹ but the role of angiotensin II (Ang II), a major regulator of blood pressure, was not considered. Elevated levels of Ang II may confer protection against malaria morbidity and mortality, providing an alternative explanation for hypertension in malaria endemic areas.

OBJECTIVE

To discuss a possible alternative cause for hypertension in populations who have been under the selective pressure of malaria.

METHODS AND RESULTS

We reviewed published scientific literature for studies that could establish a link between Ang II and malaria. Both genetic and functional studies suggested that high levels of Ang II may confer protection against cerebral malaria by strengthening the integrity of the endothelial brain barrier. We also describe strong experimental evidence supporting our hypothesis through genetic, functional, and interventional studies.

CONCLUSIONS

A causal association between high levels of Ang II and protection from malaria pathogenesis can provide a likely explanation for the increased prevalence in hypertension observed in populations of African and South Asian origin. Furthermore, this potential causative connection might also direct unique approaches for the effective treatment of cerebral malaria.

Association between circulating levels of ACE2-Ang-(1-7)-MAS axis and ACE2 gene polymorphisms in hypertensive patients

The angiotensin-converting enzyme 2-angiotensin-(1-7)-MAS axis (ACE2-Ang-[1-7]-MAS axis) plays an important role in the control of blood pressure. Some previous studies indicated that the genetic variants of ACE2 may have a potential to influence this axis. Therefore, the present study aimed at examining the association of ACE2 polymorphisms with circulating ACE2 and Ang-(1-7) levels in patients with essential hypertension.Hypertensive patients who met the inclusion criteria were enrolled in the present study. Three Tag single-nucleotide polymorphisms (rs2106809, rs4646155, and rs879922) in ACE2 gene were genotyped for all participants. Circulating ACE2 and Ang-(1-7) levels were detected by enzyme-linked immunosorbent assay.There were 96 (53.0%) females and 85 (47.0%) males participating in the present study. The circulating Ang-(1-7) levels were significantly greater in female patients carrying the rs2106809 CC or CT genotype compared with those carrying the TT genotype (1321.9 ± 837.4 or 1077.5 ± 804.4 pg/mL vs 751.9 ± 612.4 pg/mL, respectively; P = 0.029, analysis of variance), whereas the circulating Ang-(1-7) levels were comparable among genotypes in male patients. In addition, there was no significant difference in the circulating ACE2 levels among rs2106809 CC, CT, and TT genotype groups in both female and male patients. The circulating ACE2 and Ang-(1-7) levels were related to neither rs4646155 nor rs879922 in female or male patients.In conclusion, the rs2106809 polymorphism of the ACE2 gene may be a determinant of the circulating Ang-(1-7) level in female patients with hypertension, suggesting a genetic association between circulating Ang-(1-7) levels and ACE2 gene polymorphisms in patients with hypertension.

A Physiologic Approach to the Pharmacogenomics of Hypertension

Hypertension is a multifactorial condition with diverse physiological systems contributing to its pathogenesis. Individuals exhibit significant variation in their response to antihypertensive agents. Traditional markers, such as age, gender, diet, plasma renin level, and ethnicity, aid in drug selection. However, this review explores the contribution of genetics to facilitate antihypertensive agent selection and predict treatment efficacy. The findings, reproducibility, and limitations of published studies are examined, with emphasis placed on candidate genetic variants affecting drug metabolism, the renin-angiotensin system, adrenergic signalling, and renal sodium reabsorption. Single-nucleotide polymorphisms identified and replicated in unbiased genome-wide association studies of hypertension treatment are reviewed to illustrate the evolving understanding of the disease's complex and polygenic pathophysiology. Implementation efforts at academic centers seek to overcome barriers to the broad adoption of pharmacogenomics in the treatment of hypertension. The level of evidence required to support the implementation of pharmacogenomics in clinical practice is considered.

SLCO1B1 Variants and Angiotensin Converting Enzyme Inhibitor (Enalapril)-Induced Cough: a Pharmacogenetic Study

Clinical observations suggest that incidence of cough in Chinese taking angiotensin converting enzyme inhibitors is much higher than other racial groups. Cough is the most common adverse reaction of enalapril. We investigate whether SLCO1B1 genetic polymorphisms, previously reported to be important determinants of inter-individual variability in enalapril pharmacokinetics, are associated with the enalapril-induced cough. A cohort of 450 patients with essential hypertension taking 10 mg enalapril maleate were genotyped for the functional SLCO1B1 variants, 388A > G (Asn130Asp, rs2306283) and 521T > C (Val174Ala, rs4149056). The primary endpoint was cough, which was recorded when participants were bothered by cough and respiratory symptoms during enalapril treatment without an identifiable cause. SLCO1B1 521C allele conferred a 2-fold relative risk of enalapril-induced cough (95% confidence interval [CI] = 1.34-3.04, P = 6.2 × 10(-4)), and haplotype analysis suggested the relative risk of cough was 6.94-fold (95% CI = 1.30-37.07, P = 0.020) in SLCO1B1*15/*15 carriers. Furthermore, there was strong evidence for a gene-dose effect (percent with cough in those with 0, 1, or 2 copy of the 521C allele: 28.2%, 42.5%, and 71.4%, trend P = 6.6 × 10(-4)). Our study highlights, for the first time, SLCO1B1 variants are strongly associated with an increased risk of enalapril-induced cough. The findings will be useful to provide pharmacogenetic markers for enalapril treatment.

Genetic Variants of C-5312T REN Increased Renin Levels and Diastolic Blood Pressure Response to Angiotensin Receptor Blockers

Renin catalyzes the cleavage of angiotensinogen into angiotensin I. Genetic variant C-5312T of renin enhancer has been reported to increase in vitro renin gene transcription. However, no obvious in vivo study was performed to see the renin level in C-5312T when treated with angiotensin receptor blockers (ARB). Therefore, this study aimed to investigate the serum renin level and blood pressure response in ARB treated hypertensive patients. Single nucleotide polymorphism (SNP) of C-5312T was identified in 55 hypertensive patients by using multiplex PCR and renin serum level was assayed by ELISA. The data showed that the increase of serum renin levels after 5 months of ARB treatment was significantly higher in patients with CT/TT genotype (10 pg/mL) than those with CC genotype (4.08 pg/mL) (P = 0.025). Hypertensive patients with CT/TT genotypes also showed less diastolic pressure reduction than CC genotypes in hypertensive patients with valsartan treatment (P = 0.04) or telmisartan treatment (P = 0.03). Finally, these findings suggested that SNP of C-5312T REN enhancer might contribute to higher increased renin serum levels and less diastolic blood pressure response to ARB treatment.

The association between angiotensin-converting enzyme 2 polymorphisms and essential hypertension risk: A meta-analysis involving 14,122 patients

BACKGROUND

Some studies have evaluated the associations between the angiotensin-converting enzyme 2 (ACE2) gene polymorphisms and essential hypertension (EH) risk. However, the results remain uncertain. We carried out a meta-analysis to derive a more comprehensive estimation of these associations.

METHODS

Case-control studies were identified by searching PubMed, EMBASE, Chinese National Knowledge Infrastructure (CNKI) and Wangfang databases. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of the associations.

RESULTS

Significant associations were found between the ACE2 G8790A polymorphism and EH risk in males (OR = 1.27; 95% CI, 1.11-1.44; p = 0.0004; I(2) = 34%) and females (OR = 1.21; 95% CI, 1.09-1.34; p = 0.0003; I(2) = 31%), respectively. Significant associations were also observed between the ACE2 rs2106809 polymorphism and EH risk in males (OR = 1.24; 95% CI, 1.10-1.39; p = 0.0004; I(2) = 18%) and females (OR = 1.39; 95% CI, 1.27-1.51; p < 0.00001; I(2) = 0%), respectively. However, there was no significant association between the ACE2 A1075G polymorphism and EH risk in males (OR = 1.27; 95% CI, 0.77-2.10; p = 0.35; I(2) = 69%) and females (OR = 1.02; 95% CI, 0.83-1.26; p = 0.84; I(2) = 33%), respectively.

CONCLUSIONS

These results suggest that the ACE2 G8790A and rs2106809 polymorphisms may be associated with EH risk.

From gene to protein-experimental and clinical studies of ACE2 in blood pressure control and arterial hypertension

Hypertension is a major risk factor for stroke, coronary events, heart and renal failure, and the renin-angiotensin system (RAS) plays a major role in its pathogenesis. Within the RAS, angiotensin converting enzyme (ACE) converts angiotensin (Ang) I into the vasoconstrictor Ang II. An “alternate” arm of the RAS now exists in which ACE2 counterbalances the effects of the classic RAS through degradation of Ang II, and generation of the vasodilator Ang 1-7. ACE2 is highly expressed in the heart, blood vessels, and kidney. The catalytically active ectodomain of ACE2 undergoes shedding, resulting in ACE2 in the circulation. The ACE2 gene maps to a quantitative trait locus on the X chromosome in three strains of genetically hypertensive rats, suggesting that ACE2 may be a candidate gene for hypertension. It is hypothesized that disruption of tissue ACE/ACE2 balance results in changes in blood pressure, with increased ACE2 expression protecting against increased blood pressure, and ACE2 deficiency contributing to hypertension. Experimental hypertension studies have measured ACE2 in either the heart or kidney and/or plasma, and have reported that deletion or inhibition of ACE2 leads to hypertension, whilst enhancing ACE2 protects against the development of hypertension, hence increasing ACE2 may be a therapeutic option for the management of high blood pressure in man. There have been relatively few studies of ACE2, either at the gene or the circulating level in patients with hypertension. Plasma ACE2 activity is low in healthy subjects, but elevated in patients with cardiovascular risk factors or cardiovascular disease. Genetic studies have investigated ACE2 gene polymorphisms with either hypertension or blood pressure, and have produced largely inconsistent findings. This review discusses the evidence regarding ACE2 in experimental hypertension models and the association between circulating ACE2 activity and ACE2 polymorphisms with blood pressure and arterial hypertension in man.

ACE2: angiotensin II/angiotensin-(1-7) balance in cardiac and renal injury

Our current recognition of the renin-angiotensin system is more convoluted than originally thought due to the discovery of multiple novel enzymes, peptides, and receptors inherent in this interactive biochemical cascade. Over the last decade, angiotensin-converting enzyme 2 (ACE2) has emerged as a key player in the pathophysiology of hypertension and cardiovascular and renal disease due to its pivotal role in metabolizing vasoconstrictive/hypertrophic/proliferative angiotensin II into favorable angiotensin-(1-7). This review addresses the considerable advancement in research on the role of tissue ACE2 in the development and progression of hypertension and cardiac and renal injury. We summarize the results from recent clinical and experimental studies suggesting that serum or urine soluble ACE2 may serve as a novel biomarker or independent risk factor relevant for diagnosis and prognosis of cardiorenal disease. We also review recent proceedings on novel therapeutic approaches to enhance ACE2/angiotensin-(1-7) axis.

The association between the Angiotensin-Converting Enzyme-2 gene and blood pressure in a cohort study of adolescents

BACKGROUND

The Angiotensin-Converting Enzyme-2 (ACE2) gene, located on chromosome X, is believed to be implicated in blood pressure regulation. However the few studies that have examined this association have yielded mixed results. The objective of this study was to assess the association between tag single nucleotide polymorphisms (SNPs) in the angiotensin-converting enzyme-2 gene with blood pressure and blood pressure change in adolescents.

METHODS

Participants in the Nicotine Dependence in Teens (NDIT) cohort study with blood or saliva samples and at least 3 blood pressure measurements over 5 years were included in the analytic sample (n = 555). Linear growth curve models stratified on sex and ethnicity were used to assess the association between four tag SNPs in the ACE2 gene and systolic (SBP) and diastolic blood pressure (DBP), and blood pressure change.

RESULTS

In males of European descent, rs2074192 and rs233575 were significantly associated with SBP and DBP, and rs2158083 was associated with SBP. In French Canadian males, rs233575 and rs2158083 were significantly associated with DBP. Among females of European descent, rs2074192, rs233575, and rs2158083 were significantly associated with change in SBP over 5 years.

CONCLUSIONS

This is the first study to assess the association between the ACE2 gene with blood pressure and blood pressure change in a cohort of adolescents. Results indicate that several ACE2 gene SNPs are associated with blood pressure or blood pressure change in persons of European descent. However the therapeutic potential of these SNPs should be explored.

Association of angiotensin-converting enzyme and angiotensin-converting enzyme-2 gene polymorphisms with essential hypertension in the population of Odisha, India

BACKGROUND

Hypertension is a serious health issue worldwide and essential hypertension, which includes 90-95% of the cases, is influenced by both genetic and environmental factors. Identification of these factors may help in control of this disease. The Insertion/Deletion (I/D) polymorphism in Angiotensin-Converting Enzyme (ACE) gene and rs2106809 (C > T) polymorphism in Angiotensin-Converting Enzyme 2 (ACE2) gene have been reported to be associated with essential hypertension in different populations.

AIM

To investigate the association of ACE I/D and ACE2 rs2106809 polymorphisms with essential hypertension in the population of Odisha, an eastern Indian state.

SUBJECTS AND METHODS

A total of 246 hypertensives (159 males and 87 females) and 274 normotensives (158 males and 116 females) were enrolled in the study. Detailed anthropometric data, tobacco, alcohol and food habits were recorded and 2 ml of venous blood was collected for biochemical and genetic analysis.

RESULTS

The DD genotype of ACE and TT genotype of ACE2 were significantly high among female hypertensives, while T allele of ACE2 was linked to male hypertensives. In the male population, alcohol was also identified as a potential risk factor.

CONCLUSION

Among females, ACE I/D and ACE2 rs2106809 polymorphisms, while among males, ACE2 rs2106809 polymorphism and alcohol consumption are associated with essential hypertension in the study population.