Association of renin-angiotensin-aldosterone system gene polymorphisms with left ventricular hypertrophy in patients with heart failure with preserved ejection fraction: A case-control study

Investigation on the association between Osteopontin and Apolipoprotein E gene polymorphisms and vancomycin-induced acute kidney injury: A pharmacokinetic/pharmacogenetic study in critically ill patients

Vancomycin is a commonly administered antibiotic for various Gram-positive infections in critically ill patients. Vancomycin has a narrow therapeutic index and its main adverse drug reaction is acute kidney injury (AKI). In this regard, various pharmacokinetic parameters have been widely considered for therapeutic drug monitoring (TDM) purposes. Higher vancomycin trough concentration and area under the curve (AUC) values would be associated with higher rates of AKI. Therefore, dose adjustment based on targeted pharmacokinetic values would be essential to avoid toxicity and achieve optimal clinical response. However, there are numerous reports regarding the discrepancy between pharmacokinetic parameter values and AKI. In this regard, we examined the possible role of pharmacogenetics in vancomycin-induced AKI to distinguish patients who are genetically prone to AKI. In this cross-sectional study, polymorphisms of osteopontin (OPN) and Apolipoprotein E (APOE) along with pharmacokinetic parameters were assessed in 87 critically ill patients admitted to ICU wards and received vancomycin. The results indicated a significant difference in OPN and APOE genotype distribution between AKI and non-AKI patients (P = 0.001 and 0.02, respectively). Stepwise multivariate logistic regression analysis showed that patients with e2e3 genotype were 4.2-fold more prone to AKI (P = 0.029; OR = 4.2; 95 %CI = 1.2-15.7). Moreover, there was a significant correlation between pharmacokinetic parameters (calculated trough concentration, AUCτ, AUC24h, and t1/2) and vancomycin-induced AKI. Genotyping the patients for OPN and APOE polymorphisms before vancomycin initiation would be promising as a routine clinical practice to obtain an efficient clinical response and prevent vancomycin-induced AKI, especially in critically ill patients.

Single nucleotide polymorphism (SNP) rs4291 of the angiotensin-converting enzyme (ACE) gene is associated with the response to losartan treatment in hypertensive patients

Arterial hypertension is characterized by systolic pressure ≥ 140 mmHg and/or diastolic pressure ≥ 90 mmHg and its treatment consists of the use of antihypertensive drugs, as losartan and hydrochlorothiazide. Blood pressure is regulated by angiotensin-converting enzyme (ACE) and polymorphisms in the ACE gene are associated to a greater predisposition to hypertension and response to treatment. The aim of this study was to evaluate the association of genetic polymorphisms of ACE rs4363, rs4291 and rs4335 and the response to antihypertensive drugs in hypertensive patients from Ouro Preto/MG, Brazil. A case-control study was carried out with 87 hypertensive patients being treated with losartan and 75 with hydrochlorothiazide, who answered a questionnaire and had blood samples collected. Biochemical analyzes were performed on serum using UV/Vis spectrophotometry and identification of ACE variants rs4363, rs4291 and rs4335 was performed by real-time PCR using the TaqMan® system. Univariate logistic regression test was performed to compare categorical data in STATA 13.0 software. The results showed that there was an influence of ACE polymorphisms on the response to losartan, demonstrating that AT or TT genotypes of rs4291 were more frequent in the group of controlled AH (54.9%), indicating that these individuals are 2.8 times more likely to of being controlled AH (95% CI 1.12-6.80, p. =0.026) compared to those with AA genotype. In contrast, no influence of ACE polymorphisms on the response to hydrochlorothiazide was observed. In conclusion, the presence of the T allele of the rs4291 variant was associated to controled blood pressure when losartan was used as an antihypertensive agent. These results show the importance of pharmacogenetic studies to detect genetic characteristics, enabling therapeutic individuality and reducing costs for the healthcare system.

Signaling pathways and genetics of brain Renin angiotensin system in psychiatric disorders: State of the art

Along the conventional pathways, Renin-angiotensin system (RAS) plays a key role in the physiology of the CNS and pathogenesis of psychiatric diseases. RAS is a complex regulatory pathway which is composed of several peptides and receptors and comprises two counter-regulatory axes. The classical (ACE1/AngII/AT1 receptor) axis and the contemporary (ACE2/Ang (1-7)/Mas receptor) axis. The genes coding for elements of both axes have been broadly studied. Numerous functional polymorphisms on components of RAS have been identified to serve as informative disease and treatment markers. This review summarizes the role of each peptide and receptor in the pathophysiology of psychiatric disorders (depression, bipolar disorders and schizophrenia), followed by a concise look at the role of genetic polymorphism of the RAS in the pathophysiology of these disorders.

Association between AT1 receptor gene polymorphism and left ventricular hypertrophy and arterial stiffness in essential hypertension patients: a prospective cohort study

BACKGROUND

AT1 receptor gene (AGTR1) is related to essential hypertension (EH), and left ventricular hypertrophy (LVH) and arterial stiffness are common complications of EH. This study aimed to explore the association between AGTR1 genotype and LVH and arterial stiffness in EH patients.

METHODS

A total of 179 EH patients were recruited in this study. Oral exfoliated cells were collected from each patient, and the genetic polymorphism of AGTR1(rs4524238) was assessed using a gene sequencing platform. The outcomes were LVH and arterial stiffness.

RESULTS

Among 179 patients, 114 were with AGTR1 genotype of GG (57 males, aged 59.54 ± 13.49 years) and 65 were with AGTR1 genotype of GA or AA (36 males, aged 61.28 ± 12.79 years). Patients with AGTR1 genotype of GG were more likely to have LVH (47 [41.23%] vs. 14 [21.54%], P = 0.006) and arterial stiffness (30 [26.32%] vs. 8 [12.31%], P = 0.036). The AGTR1 polymorphism frequency was in accordance with Hardy-Weinberg equilibrium (P = 0.291). The multivariate logistic regression showed that AGTR1 genotype of GA or AA was independently associated with lower risk of LVH (OR = 0.344, 95%CI 160~0.696, P = 0.003) and arterial stiffness (OR = 0.371, 95%CI 0.155~0.885, P = 0.025) after adjusting for gender, age, and diabetes.

CONCLUSION

EH patients with the AGTR1 genotype of GA or AA were at lower risk for LVH and arterial stiffness than those with the GG genotype.

ncRNAs and polyphenols: new therapeutic strategies for hypertension

Polyphenols have gained significant attention in protecting several chronic diseases, such as cardiovascular diseases (CVDs). Accumulating evidence indicates that polyphenols have potential protective roles for various CVDs. Hypertension (HTN) is among the hazardous CVDs accounting for nearly 8.5 million deaths worldwide. HTN is a complex and multifactorial disease and a combination of genetic susceptibility and environmental factors play major roles in its development. However, the underlying regulatory mechanisms are still elusive. Polyphenols have shown to cause favourable and beneficial effects in the management of HTN. Noncoding RNAs (ncRNAs) as influential mediators in modulating the biological properties of polyphenols, have shown significant footprints in CVDs. ncRNAs control basic functions in virtually all cell types relevant to the cardiovascular system and, thus, a direct link with blood pressure (BP) regulation is highly probable. Recent evidence suggests that a number of ncRNAs, including main small ncRNAs, microRNAs (miRNAs) and long ncRNAs (lncRNAs), play crucial roles with respect to the antihypertensive effects of polyphenols. Indeed, targeting lncRNAs by polyphenols will be a novel and promising strategy in the management of HTN. Herein, we reviewed the effects of polyphenols in HTN. Additionally, we emphasized on the potential effects of polyphenols on regulations of main ncRNAs, which imply the role of polyphenols in regulating ncRNAs in order to exert protective effects and thus proposing them as new targets for HTN treatment.Abbreviations : CVD: cardiovascular disease; BP: blood pressure; HTN: hypertension, lncRNAs: long noncoding RNAs; p38-MAPK: p38-mitogenactivated protein kinase; OPCs: oligomeric procyanidins; GTP: guanosine triphosphate; ROS: reactive oxygen species; cGMP: cyclic guanosine monophosphate; SGC: soluble guanylate cyclase; PI3K: phosphatidylinositol 3-kinase; cGMP: Cyclic GMP; eNOS: endothelial NO synthase; ERK ½: extracellular signal-regulated kinase ½; L-Arg: L-Arginine; MAPK: mitogen-activated protein kinases; NO: Nitric oxide; P: Phosphorus; PDK1: Phosphoinositide-dependent kinase 1; PI3-K: Phosphatidylinositol 3-kinase; PIP2: Phosphatidylinositol diphosphate; ncRNAs: non-protein-coding RNA; miRNAs: microRNAs; OPCs: oligomeric procyanidins; RES: resveratrol; GE: grape extract; T2DM: type 2 diabetes mellitus; IL: interleukin; TNF-α: tumour necrosis factor-alpha; NF-κB: nuclear factor NF-kappa-B; ALP: alkaline phosphatase; PARP1: poly [ADP-ribose] polymerase 1; HIF1a: Hypoxia-inducible-factor 1A; NFATc2: nuclear factor of activated T cells 2; PAD: peripheral artery disease; SHR: spontaneously hypertensive rat; RAAS: renin-angiotensin-aldosterone system; AT₁R: angiotensin type-1 receptor; Nox: NADPH oxidase; HO-1: haem oxygenase-1; JAK/STAT: Janus kinase/signal transducers/activators of the transcription; PNS: panax notoginseng saponin; snoRNA: small nucleolar RNA; hnRNA: heterogeneous nuclear RNA; VSMCs: vascular smooth muscle cells; irf7: interferon regulatory factor 7; limo2: LIM only domain 2; GWAS: genome-wide association study; GAS5: Growth arrest-specific 5; Asb3, Ankyrin repeat and SPCS box containing 3; Chac2: cation transport regulator homolog 2; Pex11b: peroxisomal membrane 11B; Sp5: Sp5 transcription factor; EGCG: epigallocatechin gallate; ApoE: Apo lipoprotein E; ERK-MAP kinase: extracellular signal-regulated kinases-mitogen-activated protein kinase; PAH: pulmonary artery hypertension; PAP: pulmonary arterial pressure; HIF1a: hypoxia-inducible-factor 1A; NFATc2: nuclear factor of activated T cells 2; HMEC-1: Human microvascular endothelial cells; stat2: signal transducers and activators of transcription 2; JNK: c-Jun N-terminal kinase; iNOS: inducible NO synthase. SNP: single nucleotide polymorphism; CAD: coronary artery disease.

Association between polymorphisms of genes involved in the Renin-Angiotensin-Aldosterone System and the adaptive morphological and functional responses to essential hypertension

Hypertensive cardiac remodeling is illustrated by increased left ventricular (LV) mass index values and/or relative wall thickness (RWT) values >0.42, and functionally by isolated alteration of LV diastole (abnormal relaxation). The aim of the present study was to establish differentiated models of anatomical and functional adaptation to essential hypertension (EHT), in relation to the genetic variants of genes involved in the Renin-Angiotensin-Aldosterone System (RAAS). The M235T-AGT, I/D-ACE, A1166C-R1AngII, A3123C-R2AngII and G83A-REN genotypes were determined using PCR-Restriction Fragment Length Polymorphism in 139 hypertensive subjects. The relationship between the studied RAAS gene polymorphisms with morphological and functional cardiac remodeling was assessed by multiple logistic regression analysis. Patients carrying the C/C, A/C genotypes (A3123C-R2AngII polymorphism) had a 2.72-fold (P=0.033) increased risk of exhibiting an RWT value <0.42; in the multivariate model the risk was 4.02-fold higher (P=0.008). Analysis of LV diastolic dysfunction (LVDD) revealed that hypertensive patients carrying the T/T, M/T genotypes (M235T-AGT polymorphism) had a 2.24-fold (P=0.037) increased risk of developing LVDD and a 2.42-fold increased risk (P=0.039) after adjustment for confounders. Similarly, carriers of the G/G, A/G genotypes (G83A-REN) had a 2.32-fold (P=0.021) increased risk of developing LVDD, and this remained an independent risk factor based on the multivariate model (P=0.033). The results of the present study showed that no particular gene was associated with increased LV mass, but the A3123C-R2AngII polymorphism was associated with a non-concentric type of cardiac response in hypertensive patients. Conversely, the M235T-AGT and G83A-REN polymorphisms were found to be statistically significantly associated with LVDD when assessing abnormal relaxation.

Effect of sacubitril valsartan on cardiac function and endothelial function in patients with chronic heart failure with reduced ejection fraction

OBJECTIVE

The aim of the present study was to observe the effect of sacubitril valsartan on cardiac function and vascular endothelial function in patients with chronic heart failure with reduced ejection fraction (HFrEF).

METHODS

A total of 80 patients with HFrEF were randomly divided into an observation group and a control group, with 40 patients in each group. Sacubitril valsartan was added to the conventional treatment in the observation group, and perindopril was added to the conventional treatment in the control group. Both groups were treated continuously for 12 weeks. The left ventricular ejection fraction (LVEF), left ventricular end-diastolic diameter (LVEDD), flow-mediated vasodilatory function (FMD) of the brachial artery, and levels of plasma Ang II, endothelin 1 (ET-1), and calcitonin gene-related peptide (CGRP), together with the serum nitric oxide (NO) and NO synthase (NOS) were compared before and after treatment in the groups.

RESULTS

Before the treatment, the levels of LVEF, LVEDD, FMD, Ang II, ET-1, CGRP, NO, and NOS in the observation group were not significantly different from those in the control group (P > 0.05). However, the levels of LVEF, FMD, CGRP, NO, and NOS in both groups were significantly higher after the treatment than those before the treatment (P < 0.05) and significantly higher in the observation group than those in the control group. The difference was statistically significant (P < 0.05). Meanwhile, the levels of LVEDD, Ang II, and ET-1 in both groups decreased significantly after the treatment (P < 0.05) and were significantly lower in the observation group than those in the control group. The difference was statistically significant (P < 0.05).

CONCLUSION

Sacubitril valsartan might improve endothelial function while increasing cardiac function in HFrEF patients.

Risks of incident heart failure with preserved ejection fraction in Chinese patients hospitalized for cardiovascular diseases

Background

Endogenous aldehyde damages DNA and potentiates an ageing phenotype. The aldehyde dehydrogenase 2 (ALDH2) rs671 polymorphism has a prevalence of 30%–50% in Asian populations. In this study, we aimed to analyze risk factors contributing to the development of heart failure with preserved ejection fraction (HFpEF) along with the genetic exposure in Chinese patients hospitalized with cardiovascular diseases (CVD).

Methods

From July 2017 to October 2018, a total of 770 consecutive Chinese patients with normal left ventricular ejection fractions (LVEF) and established CVD (hypertension, coronary heart diseases, or diabetes) were enrolled in this prospective cross-sectional study. HFpEF was defined by the presence of at least one of symptom (dyspnoea and fatigue) or sign (rales and ankle swelling) related to heart failure; N-terminal pro-B-Type natriuretic peptide (NT pro-BNP ≥ 280 pg/mL); LVEF ≥ 50%; and at least one criterion related to elevated ventricular filling pressure or diastolic dysfunction (left atrial diameter > 40 mm, E/E' ≥ 13, E'/A' < 1 or concurrent atrial fibrillation). Logistic regression was performed to yield adjusted odds ratios (ORs) for HFpEF incidence associated with traditional and/or genetic exposures.

Results

Finally, among 770 patients with CVD, 92 (11.9%) patients were classified into the HFpEF group according to the diagnostic criteria. The mean age of the participants was 67 ± 12 years, and 278 (36.1%) patients were females. A total of 303 (39.4%) patients were ALDH2*2 variant carriers. In the univariate analysis, eight exposures were found to be associated with HFpEF: atrial fibrillation, ALDH2*2 variants, hypertension, age, anaemia, smoking, alcohol consumption and sex. Multivariable logistic regression showed that 4 ‘A’ variables (atrial fibrillation, ALDH2*2 variants, age and anaemia) were significantly associated with an increased risk of HFpEF. Atrial fibrillation was associated with a 3.8-fold increased HFpEF risk (95% CI: 2.21–6.61, P < 0.001), and the other three exposures associated with increased HFpEF risk were the ALDH2*2 variant (OR = 2.41, 95% CI: 1.49–3.87, P < 0.001), age (OR = 2.14, 95% CI: 1.27–3.60, P = 0.004), and anaemia (OR = 1.79, 95% CI: 1.05–3.03, P = 0.032). These four variables predicted HFpEF incidence in Chinese CVD patients (C-statistic = 0.745, 95% CI: 0.691–0.800, P < 0.001).

Conclusions

4 A traits (atrial fibrillation, ALDH2*2 variants, age and anaemia) were associated with an increased risk of HFpEF in Chinese CVD patients. Our results provide potential clues to the aetiology, pathophysiology and therapeutic targets of HFpEF.

Deletion Polymorphism of Angiotensin Converting Enzyme Gene is Associated with Left Ventricular Hypertrophy in Uighur Hypertension-Obstructive Sleep Apnea Hypopnea Syndrome (OSAHS) Patients

Background

This study aimed to explore the association of angiotensin converting enzyme (ACE) gene insertion/deletion polymorphisms with left ventricular hypertrophy (LVH) in Han and Uighur hypertension-OSAHS (obstructive sleep apnea hypopnea syndrome) patients in China.

Material/Methods

A total of 162 Han and 72 Uygur patients with hypertension-OSAHS were independently subdivided into an LVH group and a non-LVH (NLVH) group based on the left ventricular mass index. The insertion/deletion polymorphisms of ACE gene were determined by polymerase chain reaction. The association of ACE gene insertion/deletion polymorphisms with LVH was assessed by chi-squared test. Logistic regression analysis was performed to obtain the odds ratios and 95% confidence intervals for the risk of LVH after adjusting for confounding factors.

Results

In Uighur patients, the distributions of D allele and DD genotype showed significant differences between the LVH group and the NLVH group. The difference of DD genotype remained significant after multivariate adjustment. In contrast, no significant differences were observed in the distributions of D allele and DD genotype between the LVH group and the NLVH group in Han patients. Moreover, moderate-severe OSAHS was an independent risk factor for LVH.

Conclusions

D allele and DD genotype of ACE gene are possible genetic markers for the risk of LVH in Uighur but not Han hypertension-OSAHS patients.

The Effect of Angiotensin-Converting Enzyme Gene Polymorphisms on the Clinical Efficacy of Perindopril Prescribed for Acute Myocardial Infarction in Chinese Han Patients

Objective: Perindopril is an angiotensin-converting enzyme (ACE) inhibitor that is commonly used in the treatment of Chinese Han patients with acute myocardial infarction (AMI). However, there have been few studies on whether polymorphisms of the ACE gene affect the efficacy of perindopril or the prognosis of AMI patients. The purpose of this study was to analyze the relationship among the ACE rs121912703 (C>T), rs767880620 (C>A), and rs397514689 (C>T) gene polymorphisms and the prognosis of AMI patients and the clinical efficacy of perindopril in the treatment of AMI. Methods: The ACE genotypes at the rs121912703, rs767880620, and rs397514689 loci in 225 AMI patients treated with perindopril were determined by polymerase chain reaction/Sanger sequencing. Differences in cardiac structure, functional indicators, hemodynamic parameters, and related laboratory indicators were detected before and after treatment. Results: After administration of perindopril, improved ventricular remodeling in AMI patients with wild-type ACE was better than in patients with the ACE rs121912703, rs767880620, and rs397514689 minor variant alleles. The patients harboring wild-type ACE had lower systolic blood pressure and diastolic blood pressure than the patients harboring the minor variant alleles (p < 0.01). The contents of serum ACE and Ang II (angiotensin II) in AMI patients carrying the wild-type ACE alleles were lower than those of patients harboring any of the minor variant alleles (p < 0.01). The 3-year survival time of AMI patients carrying the wild-type ACE alleles was markedly greater compared with AMI patients carrying the mutant genes (p < 0.01). Conclusion: Mutations at the ACE rs121912703, rs767880620, and rs397514689 loci affect the efficacy of perindopril on ventricular remodeling and hemodynamics in Chinese Han AMI patients. The 3-year survival of AMI patients harboring the variant alleles is less than that of the patients harboring the wild-type gene.

The role of arterial hypertension in development heart failure with preserved ejection fraction: just a risk factor or something more?

Heart failure with preserved ejection fraction (HFpEF) is an entity that still raises many questions. The agreement about definition, pathophysiology, and therapeutic approach is still missing. Arterial hypertension is present in majority of patients with HFpEF, and it is still not clear if it represent a risk factor or "sine qua non" condition for HFpEF development. The underlying mechanisms of hypertension and HFpEF involve the same biohumoral systems: renin-angiotensin-aldosterone, sympathetic nervous system, and oxidative stress. However, not all hypertensive patients have HFpEF. The predisposition of some hypertensive patients to develop HFpEF needs to be resolved. Large randomized controlled trials did not prove the usefulness of renin-angiotensin-aldosterone inhibitors, diuretics, calcium channel blockers, and beta-blockers in HFpEF patients. The majority of studies did not succeed to demonstrate the reduction of cardiovascular and all-cause mortality in HFpEF individuals. One of the major limitations in these investigations was the inconsistency of HFpEF definition, which mainly refers to left ventricular ejection fraction (LVEF) cut-off that ranged from 40 to 50% in different studies. This review article provides the available data about pathophysiology and mechanisms that connect hypertension and HFpEF, investigations and therapy used in both conditions.

Left ventricular hypertrophy as protective factor after bypass grafting

Left ventricular hypertrophy (LVH) is a well established cardiovascular risk factor, accounting for an increase in cardiovascular morbid-mortality, although how much the magnitude and the kind of LVH could affect cardiovascular outcomes is in large part unknown. We speculate that mild LVH in absence of left ventricular (LV) chamber dilation, could play a protective role towards functional capacity, clinical outcome, cardiovascular and total morbi-mortality in conditions in which LV systolic function is generally reduced. Accordingly to many epidemiological observations, the availability of extra-quote of systolic function could lead to a significative improvement in the final outcome of some kinds of heart patients, as those undergoing bypass-grafting, where the stress for heart and cardiovascular system is always high. We suppose that the functional reserve available for patients with LVH could make the difference with respect to other patients undergoing myocardial revascularization. Similarly, the availability of a contractile reserve warranted by LVH could ensure a little gain in the outcome for patients after other major cardiovascular events (such as myocardial infarction or other heart surgery as surgical valve replacement). However, our hypothesis only involves mild LVH without LV chamber dilation, that is the initial stage of "non-dilated concentric" LVH and "non-dilated eccentric" LVH according to the new four-tiered classification of LVH based on relative wall thickness and LV dilation. Support for our hypothesis derives from the well-known protective role of systolic function that is a major factor in almost all cardiovascular diseases, where LV ejection fraction (LVEF) has shown to significantly improve quality of life, as well as morbidity and mortality. The knowledge that mild LVH in absence of LV chamber dilation is not as harmful in such conditions as believed at present could make avoidable some drugs prescription in some stages of the disease. Furthermore, it may allow a better evaluation of the risk profile of patients with LVH undergoing some cardiovascular major events like bypass grafting, myocardial infarction or surgical heart valve replacement.

ATP2B1 rs2681472 and STK39 rs35929607 polymorphisms and risk of Hypertension in Iranian Population

Background: ATP2B1 and STK39 have been introduced as essential hypertension candidate genes. The association of these genes' variations have not been studied in Iranian population yet. Here we aimed to investigate the association of ATP2B1 rs2681472 and STK39 rs35929607 polymorphisms with the risk of hypertension in an Iranian population. Methods: We included 400 individuals in our case-control study: 200 cases with essential hypertension and 200 healthy sex and age matched controls. All subjects were genotyped for rs2681472 and rs35929607 using a PCR-RFLP method. Genotype and allele frequencies were compared between the two groups using chi-squared test. The association was further assessed under log-additive, dominant and recessive genetic models. Results: There was no association between rs2681472 and rs35929607 polymorphisms and risk of essential hypertension in our population (p>0.05). There was also no association between the studied polymorphisms and hypertension under different genetic models. Conclusion: Our study indicated that rs2681472 of ATP2B1 and rs35929607 of STK39 may not have a significant effect on the risk of essential hypertension in Iranian population. More studies are still needed to validate our results.