Aliskiren - an alternative to angiotensin-converting enzyme inhibitors or angiotensin receptor blockers in the therapy of arterial hypertension

Genetic Appraisal of RAAS-Associated SNPs: REN (rs16853055), AGT (rs3789678) and ACE (rs4305) in Preeclamptic Women Living with HIV Infection

PURPOSE OF REVIEW

The primary goal of this review article was to determine whether the three RAAS-associated SNPs, Renin-rs16853055, AGT-rs3789678 and ACE-rs4305 are genetically linked to the development of hypertension in preeclampsia. The secondary goal was to establish if there was a link between these SNPs and HIV infection.

RECENT FINDINGS

There is a paucity of findings related to the aforementioned SNPs and preeclampsia. There are no recent findings on the rs16853055 renin polymorphism. The rs3789678 angiotensinogen polymorphism correlated significantly with gestational hypertension. The rs4305 ACE polymorphism showed no significant association with the development of pregnancy-induced hypertension. There are conflicting findings when determining the relationship between ethnicity and the predisposition of preeclampsia and hypertension in relation to the discussed RAAS-associated SNPs. To date, the association between RAAS-associated SNPs and preeclamptic women co-morbid with HIV in South Africa has revealed that certain alleles of the AGT gene are more prominent in HIV-infected PE compared to normotensive pregnant HIV-infected women.

No Association Between AGT Gene Polymorphisms with Hypertension in a South African Population

Purpose

Hypertension is a leading cause of cardiovascular-related morbidity and mortality worldwide, with a prevalence increasing at an alarming rate in both middle- and low-income countries. Various environmental and genetic factors have been attributed to play a significant role in the increasing prevalence of hypertension. Single nucleotide polymorphisms (SNPs) in the angiotensinogen (AGT) gene are reported to have a significant association with hypertension; however, there are limited studies done on South African populations. Therefore, this case-control study aimed to investigate the association between AGT SNPs (rs2004776, rs3789678, rs5051 and rs7079) with hypertension in a study population of isiXhosa-speaking participants from the Eastern Cape Province in South Africa.

Materials and Methods

The SNPs were genotyped in 250 hypertensive cases and 237 normotensive controls, using TaqMan genotyping assays.

Results

For the SNP rs2004776, the frequency of CC genotype (18.4%) and C allele (44%) in hypertensive cases showed no significant differences (p = 0.52, χ2 = 1.32), when compared to the normotensive control group (CC: 19.8% and C allele: 43%). Similar results were obtained for the genotypic and allelic frequencies between hypertensive cases and normotensive controls for rs3789678 (p = 0.88, χ2=0.26) and rs5051 (p = 0.57, χ2=1.12), and rs7079 (p = 0.33, χ2=2.23). These findings demonstrate that there were no significant associations between the SNPs rs2004776, rs3789678, rs7079, rs5051 with hypertension in our study population.

Conclusion

These findings suggest that AGT gene polymorphisms are not associated with the development of hypertension in the studied population. The present study represents the first genetic report to investigate the AGT gene polymorphisms with hypertension in an isiXhosa-speaking South African population.

Renin-angiotensin-aldosterone system gene polymorphisms in gestational hypertension and preeclampsia: A case-control gene-association study

Pregnancy-induced hypertension (PIH, including preeclampsia [PE] and gestational hypertension [GH]) and cardiovascular diseases (CVDs) have some metabolic changes and risk factors in common. Many studies have reported associations between single nucleotide polymorphisms (SNPs) of renin-angiotensin-aldosterone system (RAAS) genes and CVDs (particularly hypertension), and their findings have provided candidate SNPs for research on genetic correlates of PIH. We explored the association between hypertension-related RAAS SNPs and PIH in a Chinese population. A total of 130 cases with PE, 67 cases with GH, and 316 controls were recruited. Six candidate SNPs of the RAAS system were selected. Multiple logistic regression analysis adjusting for maternal age, fetal sex, and gestational diabetes mellitus showed significant associations between angiotensinogen (AGT) rs3789678 T/C and GH (p = 0.0088) and between angiotensin II receptor type 1 (AGTR1) rs275645 G/A and PE (p = 0.0082). The study population was further stratified by maternal age (<30 and ≥30 years), and stratified and crossover analyses were conducted to determine genetic associations in different age groups. Our findings suggest that the impacts of different SNPs might be affected by maternal age; however, the effect of this potential gene-age interaction on PIH needs further exploration.

Lipids, blood pressure and kidney update 2015

The most important studies and guidelines in the topics of lipid, blood pressure and kidney published in 2015 were reviewed. In lipid research, the IMProved Reduction of Outcomes: Vytorin Efficacy International Trial (IMPROVE-IT) trial revalidated the concept "lower is better" for low density lipoprotein (LDL)-cholesterol as a target for therapy, increasing the necessity of treatment the high-risk patients to achieve LDL-C goals. After these results, ezetimibe might become the preferred additional drug in the combination therapy of lipid disorders because of oral dosage form and lower acquisition cost. However, for the statin-intolerant patients and those patients requiring essential reductions in LDL-C to achieve their goals, new therapies, including PCSK9 inhibitors remain promising drugs. In blood pressure research, American Heart Association (AHA)/American College of Cardiology (ACC) 2015 guidelines recommended a target for blood pressure below 140/90 mmHg in stable or unstable coronary artery disease patients and below 150/90 mmHg in patients older than 80 years of age, however the recent results of the Systolic Blood Pressure Intervention Trial (SPRINT) trial have suggested that there might be significant benefits, taking into account cardiovascular risk, for hypertensive patients over 50 without diabetes and blood pressure levels <120/80. In kidney research, reducing the progression of chronic kidney disease and related complications such as anemia, metabolic acidosis, bone and mineral diseases, acute kidney injury and cardiovascular disease is still a goal for clinicians.

Lipids, blood pressure and kidney update 2014

This paper is an effort to review all the most important studies and guidelines in the topics of lipid, blood pressure and kidney published in 2014. Irrespective of advances, the options for improving simultaneous hypercholesterolemia and hypertension management (as well as its complication - chronic kidney disease) remain a problem. Recommending hypolidemic, hypotensive and kidney disease drugs to obtain therapy targets in cardiovascular, diabetic, elderly and kidney disease (=high risk) patients might strengthen risk factor control, improve compliance and the therapy efficacy, and in the consequence reduce the risk of cardiovascular events and mortality rate. That is why the authors have decided to summary and discuss the recent scientific achievements in the field of lipid, blood pressure and kidney.