Clinical and genetic analysis of essential hypertension with mitochondrial tRNAMet 4435A>G and YARS2 mutation

OBJECTIVES

To investigate the role of m.4435A>G and YARS2 c.572G>T (p.G191V) mutations in the development of essential hypertension.

METHODS

A hypertensive patient with m.4435A>G and YARS2 p.G191V mutations was identified from previously collected mitochondrial genome and exon sequencing data. Clinical data were collected, and a molecular genetic study was conducted in the proband and his family members. Peripheral venous blood was collected, and immortalized lymphocyte lines constructed. The mitochondrial transfer RNA (tRNA), mitochondrial protein, adenosine triphosphate (ATP), mitochondrial membrane potential (MMP), and reactive oxygen species (ROS) in the constructed lymphocyte cell lines were measured.

RESULTS

Mitochondrial genome sequencing showed that all maternal members carried a highly conserved m.4435A>G mutation. The m.4435A>G mutation might affect the secondary structure and folding free energy of mitochondrial tRNA and change its stability, which may influence the anticodon ring structure. Compared with the control group, the cell lines carrying m.4435A>G and YARS2 p.G191V mutations had decreased mitochondrial tRNA homeostasis, mitochondrial protein expression, ATP production and MMP levels, as well as increased ROS levels (all P<0.05).

CONCLUSIONS

The YARS2 p.G191V mutation aggravates the changes in mitochondrial translation and mitochondrial function caused by m.4435A>G through affecting the steady-state level of mitochondrial tRNA and further leads to cell dysfunction, indicating that YARS2 p.G191V and m.4435A>G mutations have a synergistic effect in this family and jointly participate in the occurrence and development of essential hypertension.

Contribution of NOS3AS Variants to Susceptibility to Essential Hypertension: A Study in Kermanshah Province, Western Iran

Hypertension (HTN) is a global health challenge and increase the risk of cardiovascular disease. Hypertension has a multifactorial course of evolution, with both genetic and environmental factors playing an important role. To date, a number of genes and pathways have been proposed to be associated with HTN, among which is Nitric Oxide pathway. NO levels can be regulated by reactive oxygen species (ROS), superoxide and post-transcriptional mechanisms, including sense-anti sense interactions. NOS3AS gene encodes an antisense RNA (sONE) which is complementary to NOS3 transcript in 662 nucleotides and may regulate NOS3 in a post-transcriptional manner. In this study, we sought to define the role of NOS3AS in the pathophysiology of essential HTN. A total of 131 cases with hypertension and 115 controls were enrolled in the study. Peripheral blood was drawn from all study participants after signing the informed consent form. Three variants (rs71539868, rs12666075 and rs7830) were investigated by Tetra-ARMS PCR method. The results were then statistically analyzed. We found statistically significant association between rs7830 TT genotype, rs12666075 GT and TT genotypes with susceptibility to HTN. We failed to observe association between rs71539868 and susceptibility to HTN. The present study showed a strong association between NOS3AS variants and susceptibility to hypertension in the population of Kermanshah province. Our results may shed more light on the mechanisms of disease development and may also help to better identify genetic predispositions and individuals at risk.

Clinical and genetic analysis of essential hypertension with CYB gene m.15024G>A mutation

OBJECTIVES

To explore the role of mitochondrial CYB 15024G>A mutation in the development of essential hypertension.

METHODS

Mitochondrial genome sequences of hypertensive patients were obtained from previous studies. Clinical and genetic data of a hypertensive patient with mitochondrial CYB 15024G>A mutation and its pedigree were analyzed. Lymphocytes derived from patient and family members were transformed into immortalized lymphoblastoid cell lines, and the levels of adenosine triphosphate (ATP), mitochondrial membrane potential and intracellular reactive oxygen species (ROS) were detected.

RESULTS

The penetrance of this essential hypertension family was 42.9%, and the age of onset was 46-68 years old. Mitochondrial genome sequencing results showed that all maternal members carried a highly conserved mitochondrial CYB 15024G>A mutation. This mutation could affect the free energy of mitochondrial CYB for secondary and tertiary structure and protein folding, thereby changing its structural stability and the structure of the electron transfer function area around the mutation site. Compared with the control, the cell line carrying the mitochondrial CYB 15024G>A mutation showed significantly decreased levels of mitochondrial CYB, ATP and mitochondrial membrane potential, and increased levels of ROS (P<0.01).

CONCLUSIONS

Mitochondrial CYB 15024G>A mutation may affect the structure of respiratory chain subunits and mitochondrial function, leading to cell dysfunction, which suggests that the mutation may play a synergistic role in essential hypertension.

Polymorphism of NOS3 gene and its association with essential hypertension in Guizhou populations of China

OBJECTIVE

A case-control study was conducted to evaluate the relationship between endothelial nitric oxide synthase (NOS3) gene polymorphism and essential hypertension in the Han, Miao, and Buyi populations in Guizhou China.

METHODS

DNA was collected from the blood samples of 353 essential hypertension patients and 342 healthy controls from Guizhou province of China. Eight polymorphisms of the NOS3 gene were genotyped using the Sequenom MassARRAY platform. For genetic analysis, SPSS 26.0, Haploview, SNPStats, SHEsis, and MDR were utilized.

RESULTS

All SNPs (rs11771443, rs1808593, rs753482, rs3918186, rs3918188, rs3918227, rs7830, and rs891512) satisfied the Hardy-Weinberg equilibrium test (P > 0.05). The allele and genotype frequencies of rs7830 and rs1808593 in case-control groups demonstrated significant differences (P < 0.05). Compared to the TT genotype of rs1808593, the TG or GG genotype reduced the risk of hypertension in the Miao population (OR = 0.410, 95% CI: 0.218-0.770, P = 0.006). Compared to the GG or GT genotype of rs7830, the TT genotype increased the risk of hypertension in the overall populations (OR = 1.716, 95%CI: 1.139-2.586, P = 0.010). The CATT (rs3918227-rs391818186-rs1808593-rs7830) haplotype was a risk factor for hypertension in the Miao and Han populations (OR = 1.471, 95%CI: 1.010-2.143, P = 0.044 and OR = 1.692, 95%CI: 1.124-2.545, P = 0.011). The CAGG haplotype in the Miao population was a protective factor against hypertension (OR = 0.555, 95%CI: 0.330-0.934, P = 0.025). The rs3918188, rs1808593, and rs7830 in the Miao population showed an interaction effect on hypertension (P < 0.001). The rs11771443, rs3918188, and rs7830 in the Buyi and Han populations showed an interaction effect on hypertension (P = 0.013 and P < 0.001).

CONCLUSION

The single nucleotide polymorphisms rs1808593 and rs7830 of NOS3 gene are associated with essential hypertension in Guizhou ethnic populations.

Insulin receptor substrate-1 gene polymorphism and lipid panel data in type 2 diabetic patients with comorbid obesity and/or essential hypertension

Objective. The hallmarks of type 2 diabetes mellitus (T2DM) are insulin resistance (IR) and insulin receptor substrate (IRS) proteins essential for the insulin signaling. IRS-1 gene has not only been shown to be associated with T2DM, but also has indicated that it may significantly correlate with diabetic complications, such as coronary heart disease and obesity. The aim of this study was to evaluate changes of the lipid panel data in T2DM patients with comorbid obesity and/or essential hypertension in connection with the IRS-1 (rs2943640) polymorphism. Methods. The study involved 33 T2DM patients and 10 healthy individuals. The IRS-1 (rs2943640) polymorphism was genotyped using a TaqMan real-time polymerase chain reaction method. Blood serum lipid panel data were determined with commercially available kits using a Cobas 6000 analyzer. Results. Analysis of the serum lipid panel data depending on the presence of the C/A alleles of IRS-1 (rs2943640) polymorphism in T2DM patients, regardless of the presence/absence of comorbidities, showed significantly lower level of high-density lipoprotein cholesterol (HDL-C) and significantly higher level of non-HDL-C in the carriers of C allele vs. carriers of A allele. In T2DM patients with comorbid obesity and essential hypertension, proatherogenic lipid changes were found in both C and A alleles carriers. Analysis of the effect of IRS-1 (rs2943640) genotypes on serum lipid panel data in T2DM patients, regardless of the presence/absence of comorbidities, showed that the CC genotype carriers had more pronounced pro-atherogenic changes vs. carriers of СА and АА genotypes. In the comorbid course of T2DM (both in combination with obesity and obesity and essential hypertension), pro-atherogenic changes were found in the carriers of the CA genotype of IRS-1 (rs2943640) polymorphism. Conclusions. The presence of the C allele of IRS-1 (rs2943640) polymorphism in both homo-zygous and heterozygous states indicates increased risk of pro-atherogenic changes in T2DM patients with comorbid obesity and/or essential hypertension.

The association between Alu hypomethylation and the severity of hypertension

Introduction

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

Results

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

Conclusions

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

LPIN1 is a new target gene for essential hypertension

BACKGROUND

We previously showed Lipin1 (LPIN1) to be a candidate gene for essential hypertension by genome-wide association studies. LPIN1 encodes the Lipin 1 protein, which contributes to the maintenance of lipid metabolism and glucose homeostasis. However, little is known about the association between LPIN1 and blood pressure (BP).

METHODS

We evaluated the BP of LPIN1-deficient [fatty liver dystrophy (fld)] mice and explored related mechanisms.

RESULTS

Fld mice have very low expression of LPIN1 and exhibit fatty liver, hypertriglyceridemia, insulin resistance and peripheral neuropathy. Fld mice had significantly elevated SBP and heart rate (HR) throughout the day as measured by a radiotelemetric method. Diurnal variation of SBP and HR was also absent in fld mice. Furthermore, urinary excretion of adrenaline and noradrenaline by fld mice was significantly higher compared with that of control mice. The BP response of fld mice to clonidine (a centrally acting α2-adrenergic receptor agonist) was greater than that of control mice. However, levels of Angiotensinogen and Renin 1 mRNA and urinary nitric oxide excretion were comparable between the two groups. The decrease in SBP at 8 weeks after fat grafting surgery was significantly greater in the transplant group compared with the sham operated group.

CONCLUSION

The elevated BP in fld mice may result from activation of the sympathetic nervous system through decreased levels of adipose cytokines. These results indicate that LPIN1 plays a crucial role in blood pressure regulation and that LPIN1 is a new target gene for essential hypertension.

Correlation between single nucleotide polymorphisms in the 3 primer untranslated region of PTX3 and the risk of essential hypertension: A case-control study

The aim of this study was to investigate the correlation between single-nucleotide polymorphisms (SNPs) in the 3 primer of untranslated region (3'UTR) of the Pentraxin 3 (PTX3) gene and the risk of essential hypertension (EHT).PTX3 genotypes, rs2614, rs111451363, and rs73158510 locus, were found in 260 patients with EHT and 260 healthy controls. Quantitative real-time polymerase chain reaction was used to detect plasma hsa-miR-4766-5p levels. Enzyme-linked immunosorbent assay was used to detect plasma PTX3 levels. The dual-luciferase reporter assay was used to identify the binding site of hsa-miR-4766-5p to the PTX3.PTX3 rs2614 locus T allele was a high risk factor for EHT (odds ratio [OR] = 2.76, 95% confidence interval [CI]: 1.86-4.09, P < .01). Sex and diabetes history affected the correlation between PTX3 gene rs2614 locus SNP and EHT risk. The CCG haplotype was a protective factor for EHT (OR = 0.40, 95% CI: 0.28-0.57, P < .01), whereas the TCG haplotype was a risk factor for EHT (OR = 2.35, 95% CI: 1.51-3.66, P < .01). The plasma PTX3 level of patients with EHT was significantly higher than that of the control group, and the difference was statistically significant (P < .01). The area under the curve for EHT diagnosis in plasma PTX3 levels was 0.62 (95% CI: 0.57-0.66, P < .01). The plasma hsa-miR-4766-5p level in patients with EHT was significantly lower than that in the control group (P < .01). The area under the curve for the diagnosis of EHT according to the plasma hsa-miR-4766-5p level was 0.88 (95% CI: 0.85-0.91, P < .01). Plasma PTX3 levels were significantly negatively correlated with hsa-miR-4766-5p levels in patients with EHT and the control group (r = -0.87, -0.85, P < .01, P < .01). The PTX3 gene rs2614 locus C allele was the target gene of hsa-miR-4766-5p.The PTX3 rs2614 locus SNP is significantly associated with EHT risk.

Role of Klotho in the Development of Essential Hypertension

Klotho has antiaging properties, and serum levels decrease with physiological aging and aging-related diseases, such as hypertension, cardiovascular, and chronic kidney disease. Klotho deficiency in mice results in accelerated aging and cardiovascular injury, whereas Klotho supplementation slows down the progression of aging-related diseases. The pleiotropic functions of Klotho include, but are not limited to, inhibition of insulin/IGF-1 (insulin-like growth factor 1) and WNT (wingless-related integration site) signaling pathways, suppression of oxidative stress and aldosterone secretion, regulation of calcium-phosphate homeostasis, and modulation of autophagy with inhibition of apoptosis, fibrosis, and cell senescence. Accumulating evidence shows an interconnection between Klotho deficiency and hypertension, and Klotho gene polymorphisms are associated with hypertension in humans. In this review, we critically review the current understanding of the role of Klotho in the development of essential hypertension and the most important underlying pathways involved, such as the FGF23 (fibroblast growth factor 23)/Klotho axis, aldosterone, Wnt5a/RhoA, and SIRT1 (Sirtuin1). Based on this critical review, we suggest avenues for further research.

CACNA1C rs1006737 SNP increases the risk of essential hypertension in both Chinese Han and ethnic Russian people of Northeast Asia

Voltage-gated Ca2+ channels play a key role in the regulation of arterial tone and blood pressure. The aim of this study was to determine whether the association of calcium voltage-gated channel subunit alpha1 C (CACNA1C) rs1006737 with essential hypertension (EH) exists in both Chinese Han and ethnic Russian populations of Northeast Asia. We used a case-control study of 2 ethnic groups in the same latitude geographical area to investigate the association between the susceptibility of EH and rs1006737 polymorphism. A total of 1512 EH patients and 1690 controls in Chinese Han people (Heilongjiang Provence, China), 250 EH patients, and 250 controls in ethnic Russian people (Chita, Russia), participated in this study. All participants were genotyped using the TaqMan SNP genotyping assay (Agena Company). Baseline characteristics and the minor allele frequencies of rs1006737 vary substantially among common Chinese Han and ethnic Russian people. Allele A was found to be a risk factor for EH in Chinese Han [(odds ratio) OR 1.705, (confidence interval) 95% CI: 1.332-2.182, P < .001] and ethnic Russian (OR 1.437; 95% CI: 1.110-1.860, P = .006). The GA genotype was significantly associated with an increased risk of hypertension (OR 1.538, 95% CI: 1.188-1.991, P = .001) for Chinese Han people, and the AA genotype (OR 2.412, 95% CI: 1.348-4.318, P = .003) for ethnic Russian people. The results of this study indicate that the A allele of the variant rs1006737 in the CACNA1C gene may be a useful genetic marker for EH risk prediction in Chinese Han and ethnic Russian populations.

Serum miR-195-5p Exhibits Clinical Significance in the Diagnosis of Essential Hypertension with Type 2 Diabetes Mellitus by Targeting DRD1

OBJECTIVES

Diagnosis and management of essential hypertension (EH) or type 2 diabetes mellitus (T2DM) by combining comprehensive treatment and classificatory diagnosis have been continuously improved. However, understanding the pathogenesis of EH patients with concomitant T2DM and subsequent treatment remain the major challenges owing to the lack of non-invasive biomarkers and information regarding the underlying mechanisms.

METHODS

Herein, we collected 200 serum samples from EH and/or T2DM patients and healthy donors (N). Gene-expression profiling was conducted to identify candidate microRNAs with clinical significance. Then, a larger cohort of the aforementioned patients and 50 N were used to identify the correlation between the tumor suppressor miR-195-5p and EH and/or T2DM. The dual-luciferase reporter assay was used to explore the target genes of miR-195-5p. The suppressive effects of miR-195-5p on the 3'-UTR of the dopamine receptor D1 (DRD1) transcript in EH patients with concomitant T2DM were verified as well.

RESULTS

Compared with that in other groups, serum miR-195-5p was highly downregulated in EH patients with concomitant T2DM. miR-195-5p overexpression efficiently suppressed DRD1 expression by binding to the two 3'-UTRs. Additionally, two single nucleotide polymorphisms, including 231T-A and 233C-G, in the miR-195-5p binding sites of the DRD1 3'-UTR were further identified. Collectively, we identified the potential clinical significance of DRD1 regulation by miR-195-5p in EH patients with concomitant T2DM.

CONCLUSIONS

Our data suggested that miR-195-5p circulating in the peripheral blood served as a novel biomarker and therapeutic target for EH and T2DM, which could eventually help address major challenges during the diagnosis and treatment of EH and T2DM.

The APLNR gene polymorphism rs7119375 is associated with an increased risk of development of essential hypertension in the Chinese population: A meta-analysis

Hypertension (HT) has recently been defined as a systolic blood pressure (BP) of ≥130 mm Hg and/or a diastolic BP of ≥80 mm Hg. It is important to further understand the pathophysiology of essential HT as its proportion is larger among most of the diagnosed HT cases. The apelin and apelin receptor (APLNR) are known to play roles in regulating BP, but the putative associations of single nucleotide polymorphisms in the APLNR gene with the risk of development of essential HT have not yet been fully investigated. Herein, we conducted a meta-analysis to investigate the relationship between single nucleotide polymorphisms in the APLNR gene and the risk of essential HT.We conducted a search in the PubMed and Web of Science databases for eligible studies. The pooled odds ratios (ORs) with their 95% confidence intervals (CI) were calculated using random-effects models when heterogeneity was expected across the studies. Otherwise, fixed-effect models were used.Regarding the SNP rs7119375, 5 studies were analyzed, which included a total of 3567 essential HT patients and 3256 healthy controls. Four of the 5 studies were from China and 1 was from Mexico. The meta-analysis showed the existence of a significant association between the AA genotype of rs7119375 and the risk of developing essential HT in the Chinese population, as determined using additive and recessive models (OR, 2.11; 95% CI, 1.12-3.96; I = 86% for AA vs GG. OR, 1.53; 95% CI, 1.21-1.94; I = 28% for AA vs AG. OR, 1.88; 95% CI, 1.13-3.12; I = 79% for AA vs AG + GG).Our study showed, for the first time, the existence of an association between rs7119375 and the risk of development of essential HT in the Chinese population, although the sample size was small and there was considerable population heterogeneity. The apelin/APLNR system could be a novel therapeutic target for the treatment of essential HT, and more studies are warranted to further investigate the association.

Association between the A46G polymorphism (rs1042713) in the β2-adrenergic receptor gene and essential hypertension susceptibility in the Chinese population: A PRISMA-compliant meta-analysis

BACKGROUND

Recently, many studies have been conducted to investigate the relationship between the A46G polymorphism in the β2-adrenergic receptor (ADRB2) gene and essential hypertension risk in the Chinese population. However, the results of previous studies were conflicting.

OBJECTIVES

The present study aimed to investigate the association between the ADRB2 A46G polymorphism and the risk of essential hypertension in the Chinese population.

METHODS

We performed a systematic search of possible relevant studies on PubMed, Embase, Ovid, Web of Science, China National Knowledge Infrastructure, Wanfang, and China Biology Medicine disc databases up to January 3, 2020. Two authors independently extracted information from included articles and assessed the quality of each study by the use of the Newcastle-Ottawa Scale. According to the extent of interstudy heterogeneity, either a random-effect model or a fixed-effect model was used to calculate the combined odds ratio (OR) and 95% confidence interval (CI).

RESULTS

Finally, 16 studies containing 3390 cases and 2528 controls were included in our meta-analysis. Significant associations were found between the ADRB2 A46G polymorphism and essential hypertension risk in the Chinese population under four genetic models: allele genetic model (OR: 1.14, 95% CI: 1.06-1.23, P = .001, Pheterogeneity = .09), homozygote genetic model (OR: 1.29, 95% CI: 1.11-1.51, P = .001, Pheterogeneity = .25), dominant genetic model (OR: 1.17, 95% CI: 1.05-1.32, P = .005, Pheterogeneity = .04), and recessive genetic model (OR: 1.21, 95% CI: 1.05-1.38, P = .007, Pheterogeneity = .72).

CONCLUSION

The ADRB2 A46G polymorphism may increase the risk of essential hypertension in the Chinese population.

Fibulin-3 affects vascular endothelial function and is regulated by angiotensin II

OBJECTIVE

The aim of the present study was to investigate the effect of fibulin-3 on vascular endothelial function, and to explore the relevant underlying mechanism with regard to the involvement of angiotensin II (AngII).

METHODS

One hundred and eight patients with essential hypertension (EH) and 31 controls were included to measure the flow-mediated dilatation (FMD). Serum fibulin-3 and AngII were examined using enzyme-linked immunosorbent assay (ELISA) and radioimmunoassay. Stable transfection of fibulin-3 was conducted on human umbilical vein endothelial cells (HUVECs) and SV40T-transformed HUVECs (PUMC-HUVEC-T1 cells). Cell counting kit-8 assay, cell cycle assay, wound healing assay, Transwell assay, apoptosis assay, and tube formation assay were subsequently performed. The expression of angiogenesis-associated genes [endothelial nitric oxide synthase (eNOS) and vascular endothelial growth factor A (VEGFA)] were measured by western blot analysis. HUVECs and PUMC-HUVEC-T1 cells were treated with AngII, and with or without an inhibitor of nuclear factor κB (NF-κB), BAY 11-7082. Pro-inflammatory cytokines [interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α)] were detected by ELISA. The expression levels of fibulin-3 and p65 were then measured by western blotting.

RESULTS

Lower levels of serum fibulin-3 were accompanied by poorer FMD and higher levels of serum AngII in patients with EH. Fibulin-3 overexpression promoted cell proliferation, migration, and angiogenesis, but led to an inhibition of apoptosis. By contrast, fibulin-3 downregulation inhibited cell proliferation, migration and angiogenesis, but promoted apoptosis. AngII induced inflammation and inhibited the expression of fibulin-3. BAY 11-7082 eliminated the inhibitory effect of AngII on fibulin-3.

CONCLUSIONS

Taken together, the results of the present study have shown that serum fibulin-3 may be a predictor of vascular endothelial function in patients with EH. Fibulin-3 gene may also have a beneficial role in repairing the vascular endothelium. Furthermore, the results also suggested that fibulin-3 gene was suppressed by AngII via the NF-κB signaling pathway.

An overview of the classical and tissue-derived renin-angiotensin-aldosterone system and its genetic polymorphisms in essential hypertension

The renin-angiotensin-aldosterone system (RAAS) is a specific hormonal cascade implicated in the blood pressure control and sodium balance regulation. Several components of this pathway have been identified including renin, angiotensinogen, angiotensin-converting enzyme, angiotensins with a wide range of distinct subtypes and receptors, and aldosterone. The RAAS is not only confined to the systemic circulation but also exists locally in specific tissues such as the heart, brain, and blood vessels with a particular paracrine action. Alteration of RAAS function can contribute to the development of hypertension and the emergence of its associated end-organ damage. Genotypic variations of the different genes of RAAS cascade have been linked to the susceptibility to essential hypertension. Accordingly, to understand the pathogenesis of essential hypertension and its related complications, deep insight into the physiological and genetic aspects of RAAS with its different components and pathways is necessary. In this review, we aimed to illustrate the physiological and genetic aspects of RAAS and the underlying mechanisms which link this system to the predisposition to essential hypertension.

Gender and Age Differences Reveal Risk Patterns in COVID-19 Outbreak

By April 28th 2020, the global number of people that were viciously infected with the newfound novel corona virus (COVID-19) stood at a staggering 3 077 133 cases, as per the confirmed data released by the WHO. It has been reported that women from the Chinese Han population are associated with essential hypertension due to their relation with the 5 SNPs, namely, rs1514283, rs4646155, rs4646176, rs2285666, and rs879922, which belong to the ACE2 gene. The level of ACE2 activity was very low in normal healthy younger persons, and was reported to be increased in patients with cardiovascular diseases. Thus, there might be severe myocarditis, that may result in acute heart failure and cardiac complexities in the elderly subjects.

Identification, Heritability, and Relation With Gene Expression of Novel DNA Methylation Loci for Blood Pressure

We conducted an epigenome-wide association study meta-analysis on blood pressure (BP) in 4820 individuals of European and African ancestry aged 14 to 69. Genome-wide DNA methylation data from peripheral leukocytes were obtained using the Infinium Human Methylation 450k BeadChip. The epigenome-wide association study meta-analysis identified 39 BP-related CpG sites with P<1×10^-5. In silico replication in the CHARGE consortium of 17 010 individuals validated 16 of these CpG sites. Out of the 16 CpG sites, 13 showed novel association with BP. Conversely, out of the 126 CpG sites identified as being associated (P<1×10^-7) with BP in the CHARGE consortium, 21 were replicated in the current study. Methylation levels of all the 34 CpG sites that were cross-validated by the current study and the CHARGE consortium were heritable and 6 showed association with gene expression. Furthermore, 9 CpG sites also showed association with BP with P<0.05 and consistent direction of the effect in the meta-analysis of the Finnish Twin Cohort (199 twin pairs and 4 singletons; 61% monozygous) and the Netherlands Twin Register (266 twin pairs and 62 singletons; 84% monozygous). Bivariate quantitative genetic modeling of the twin data showed that a majority of the phenotypic correlations between methylation levels of these CpG sites and BP could be explained by shared unique environmental rather than genetic factors, with 100% of the correlations of systolic BP with cg19693031 (TXNIP) and cg00716257 (JDP2) determined by environmental effects acting on both systolic BP and methylation levels.

Endothelial Nitric Oxide Synthase Gene Polymorphisms (- 922A > G, - 786 T > C, Intron 4 b/a VNTR and 894 G > T) and Essential Hypertension: An Association Study with Haplotypes Analysis

Endothelial Nitric Oxide Synthase (eNOS) is an indispensable regulator of blood pressure through producing Nitric Oxide (NO). There is some evidence to suggest that eNOS gene polymorphisms are associated with Essential Hypertension (EHT). In this study, the potential association between eNOS 4a/4b, A922G, G894T, T786C gene polymorphisms and EHT as individual risk factors and as haplotypes are examined in the southern population of Iran (Bandar-Abbas). In this study, 200 EHT patients and 200 normotensive subjects which were matched for age and sex were included. Genotyping was performed by either utilizing Polymerase Chain Reaction (PCR) or PCR followed by Restriction Fragment length Polymorphism (RFLP) method. Our results demonstrated statistically significant associations between T786C, G894T, and 4a/4a and EHT (p < 0.05); however, A922G had no significant association with EHT (p > 0.05). Haplotype analysis also suggested that - 786C/- 922A/4a, - 786C/- 922A/4b and - 786C/- 922G/4a haplotypes were more frequent in EHT group than control group, hypothesizing a positive association with EHT. The present study has identified that the eNOS genetic variations are associated with EHT in southern population of Iran (Bandar-Abbas). These findings also suggested that a number of haplotypes of eNOS gene may be a driving factor for EHT susceptibility in respected population.

Association of the interaction between the rs9619311 and rs402007 polymorphisms and smoking with essential hypertension in Chinese Han population

BACKGROUND

To assess the association of the interaction between the rs9619311 and rs402007 polymorphisms and smoking with essential hypertension (EH) in a Chinese Han population.

METHOD

Peripheral blood samples were extracted from 422 EH patients and 280 normotensive (NT) patients in a Chinese Han population. A whole blood genomic DNA extraction kit was used to extract genomic DNA from the blood samples. Polymerase chain reaction restriction fragment length polymorphism was used to detect the rs402007 polymorphism of a disintegrin and metalloproteinase with thrombospondin type motifs 1 gene and the rs9619311 polymorphism of the tissue inhibitor of metalloproteinase-3 gene. The distributions of the genotypes and alleles between the 2 study groups (EH and NT) were compared. The main risk factors for EH were determined by using logistic regression analysis. The effects of gene-gene and gene-smoking interactions on EH were analyzed using multifactor dimensional reduction.

RESULTS

The frequencies of the rs402007 GC + CC genotype and the C allele were significantly different between the EH and NT groups (0.68 vs 0.57, χ = 8.99, P = .003, odds ratio [OR] = 1.19; 0.45 vs 0.32, χ = 22.16, P < .001, OR = 1.38). The frequencies of the rs9619311 TC + CC genotype and the C allele were also significantly different between the 2 groups (0.33 vs 0.25, χ = 4.51, P = .04, OR = 1.44; 0.18 vs 0.13, χ = 7.03, P = .01, OR = 1.50). Logistic regression analysis suggests that the rs402007 and rs9619311 polymorphisms are independent risk factors for EH (OR = 2.37, 1.86; P < .001, respectively). The multifactor dimensionality redundant analysis results showed that the interaction among rs402007, rs9619311, and smoking was statistically significant (P = .001).

CONCLUSIONS

A disintegrin and metalloproteinase with thrombospondin type motifs 1 rs402007 and tissue inhibitor of metalloproteinase-3 rs9619311 polymorphisms are associated with EH in a Chinese Han population, and there was a positive interaction among rs402007, rs9619311, and smoking.

Blood microRNA 202-3p associates with the risk of essential hypertension by targeting soluble ST2

MicroRNA (miR)-202-3p has attracted a great deal of attention in the fields of oncology, gynecology, and metabolic disorders. However, its role in cardiovascular diseases remains to be clarified. We previously found that disruption of miR-202-3p mediated regulation of expression of soluble (s)ST2, a decoy receptor for interleukin (IL)-33, promotes essential hypertension (EH). In the present study, we first measured miR-202-3p expression levels in the blood of 182 EH cases and 159 healthy controls using TaqMan assays. miR-202-3p levels were shown to be significantly higher in EH cases than controls (fold change = 3.58, P<0.001). Logistic regression analysis revealed that higher miR-202-3p expression was associated with an increased occurrence of EH (adjusted odds ratio (OR): 1.57; 95% confidence interval (CI), 1.36-1.82; P<0.001). Addition of miR-202-3p to traditional risk factors showed an additive prediction value for EH. Further functional experiments indicated that miR-202-3p could be induced by angiotensin II (Ang II) and inhibited by Ang II-triggered soluble ST2 (sST2) expression in a negative feedback manner. Moreover, blood miR-202-3p levels were negatively correlated with sST2 expression in vivo. Our study shows that blood miR-202-3p levels were significantly associated with the occurrence of EH. These findings indicate that miR-202-3p exerts a protective role against EH by antagonizing the induction of sST2 by Ang II.

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

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

Modulation of Cardiovascular Function in Primary Hypertension in Rat by SKA-31, an Activator of KCa2.x and KCa3.1 Channels

The aim of this study was to investigate the hemodynamic effects of SKA-31, an activator of the small (K_Ca2.x) and intermediate (K_Ca3.1) conductance calcium-activated potassium channels, and to evaluate its influence on endothelium-derived hyperpolarization (EDH)-K_Ca2.3/K_Ca3.1 type relaxation in isolated endothelium-intact small mesenteric arteries (sMAs) from spontaneously hypertensive rats (SHRs). Functional in vivo and in vitro experiments were performed on SHRs or their normotensive controls, Wistar-Kyoto rats (WKY). SKA-31 (1, 3 and 10 mg/kg) caused a brief decrease in blood pressure and bradycardia in both SHR and WKY rats. In phenylephrine-pre-constricted sMAs of SHRs, SKA-31 (0.01–10 µM)-mediated relaxation was reduced and SKA-31 potentiated acetylcholine-evoked endothelium-dependent relaxation. Endothelium denudation and inhibition of nitric oxide synthase (eNOS) and cyclooxygenase (COX) by the respective inhibitors l-NAME or indomethacin, attenuated SKA-31-mediated vasorelaxation. The inhibition of K_Ca3.1, K_Ca2.3, K_IR and Na⁺/K⁺-ATPase by TRAM-34, UCL1684, Ba²⁺ and ouabain, respectively, reduced the potency and efficacy of the EDH-response evoked by SKA-31. The mRNA expression of eNOS, prostacyclin synthase, K_Ca2.3, K_Ca3.1 and K_IR were decreased, while Na⁺/K⁺-ATPase expression was increased. Collectively, SKA-31 promoted hypotension and vasodilatation, potentiated agonist-stimulated vasodilation, and maintained K_Ca2.3/K_Ca3.1-EDH-response in sMAs of SHR with downstream signaling that involved K_IR and Na⁺/K⁺-ATPase channels. In view of the importance of the dysfunction of endothelium-mediated vasodilatation in the mechanism of hypertension, application of activators of K_Ca2.3/K_Ca3.1 channels such as SKA-31 seem to be a promising avenue in pharmacotherapy of hypertension.

The dominant models of KCNJ11 E23K and KCNMB1 E65K are associated with essential hypertension (EH) in Asian: Evidence from a meta-analysis

BACKGROUND

The K channel, subfamily J, member-11 (KCNJ11) E23K and β1 subunit of large-conductance Ca-activated K channel (KCNMB1) E65K polymorphisms were shown to be associated with the risk of essential hypertension (EH). However, the results were inconclusive with relatively small sample size. Thus, we carried out a meta-analysis to investigate the genetic association between KCNJ11 E23K and KCNMB1 E65K polymorphisms and essential hypertension risk.

METHODS

Relative studies were collected using PubMed, Web of Science, the Cochrane Library databases, Chinese National Knowledge Infrastructure and Embase databases. Pooled odds ratios with 95% confidence intervals were used to assess the strength of associations.

RESULTS

The dominant models of KCNJ11 E23K (P = .006, OR [95%CI] = 0.45 [0.25, 0.79]) and KCNMB1 E65K (P = .04, OR [95%CI] = 0.91 [0.83, 1.00]) were significantly associated with essential hypertension risk. No significant association was detected between the allelic and recessive models of KCNJ11 E23K and KCNMB1 E65K and the susceptibility of EH. Subgroup analysis stratified by ethnicity showed that the dominant model of KCNMB1 E65K was associated with EH risk in Asian population (P = .003, OR [95%CI] = 0.83 [0.74, 0.94]), but not in Caucasian (P = .74, OR [95%CI] = 1.02 [0.89, 1.18]).

CONCLUSIONS

The dominant model of KCNJ11 E23K and KCNMB1 E65K might be susceptible factors for essential hypertension. To confirm this result, large-scale case-control studies with more subjects are necessary.

Microarray Profiling of Circular RNA Identifies hsa_circ_0126991 as a Potential Risk Factor for Essential Hypertension

Essential hypertension (EH), a major cause of cardiovascular diseases, is an important public health issue. However, the molecular mechanisms involved in EH remain unknown. Circular RNA (circRNA) is a novel promising biomarker for the disease. The purpose of the present study was to determine the expression of circRNAs in the blood of EH patients and to evaluate the performance of circRNA for early diagnosis of EH. A total of 178 subjects were recruited in the case-control study. Initial screening was done by using the Agilent human circRNA microarray followed by qRT-PCR validation. Finally, miRNAs were combined with circRNAs to create a new early prediction model for EH. The expression level of hsa_circ_0126991 in EH patients was significantly higher in comparison with healthy controls (p < 0.0001). Using the interaction of miR-10a-5p in combination with hsa_circ_0126991 led to a sensitivity of 0.708, a specificity of 0.764, and combined area under the curve of 0.774 (95% CI: 0.705-0.843) for early diagnosis of EH. In summary, the present study uncovered a novel perspective that hyperexpression of hsa_circ_0126991 is correlated with the risk of EH and may serve as a stable biomarker for early diagnosis of EH.

Sex-specific role of CYP24A1 rs2762939 in the risk of essential hypertension based on the serum vitamin D and total renin concentrations

CYP24A1, Vitamin D 24-hydroxylase catabolizes 25-hydroxyvitamin D (25(OH)D) and 1,25-dihydroxyvitamin D to 24-hydroxylated vitamin D products. It is widely known that low Vitamin D can lead to increased renal renin and angiotensin II production, consequently elevating blood pressure or development of essential hypertension (EH). We have conducted an investigation on hypertensives and controls to evaluate the association of the gene variant, CYP24A1 rs2762939 and 25(OH)D in an Indian population with EH. On gender-based stratification, with multivariate logistic analysis after adjustment for covariates, the CYP24A1 rs2762939 CC variant showed a higher risk of EH in males (aOR = 3.141, CI 1.164-8.478, P = .024) while females illustrated an inverse association with EH (aOR = 0.398, CI 0.172-0.092, P = .031). The 25(OH)D levels among the three genotypes of hypertensives substantiate these results. Our results clearly suggest that gender, CYP24A1 rs2762939, and Vitamin D status may play a significant role in disease susceptibility towards EH in Indian population.

KLHL3 single-nucleotide polymorphism is associated with essential hypertension in Chinese Han population

Hypertension, including secondary and essential hypertension (EH) variants, is a multifactorial disease, affecting more than one billion people worldwide. Secondary hypertension results from mutations in the putative gene KLHL3 (Kelch-like protein 3); however, it has not been reported whether the KLHL3 gene polymorphisms are associated with EH. Here, we investigated the association between KLHL3 (rs2301708 and rs7444370) polymorphisms and EH in the Chinese Han population.This case-control study included 522 subjects-260 patients with EH and 262 normotensive controls matched for age, gender, body mass index (BMI), hemoglobin A1c (HbA1c), total cholesterol (TC), triglyceride (TG), and levels of Na, K, and Cl. The distribution of functional rs2301708 and rs7444370 polymorphisms within the KLHL3 gene was assessed through polymerase chain reaction (PCR) and restriction-fragment length polymorphism (RFLP).There was no significant difference in allelic and genotypic frequencies of KLHL3 rs2301708 between the EH and normotensive groups; however, the rs7444370 T allele and CT genotype in females was significantly associated with a protective effect against EH (P = .001, P = .002; P = .019, P = .052), and the haplotype CT of rs2301708 and rs7444370 among females in the EH group was less than in the normotensive group (P = .000; P = .007).The KLHL3 rs7444370 variant could be a protective factor in the pathogenesis of females' EH.

Genetic association study between T-786C NOS3 polymorphism and essential hypertension in an Algerian population of the Oran city

BACKGROUND

Essential hypertension is an important risk factor for the development of cardiovascular disease. Important candidate genes such as NOS3 gene have been widely studied and reported to be associated with essential hypertension (HTN) in human populations.

AIM

We aim in this study to analyze the relationship between NOS3 -786T/C, a common genetic variant and HTN in a sample of the Algerian population of the Oran city.

METHODS

A case-control study has been performed in 154 subjects including 77 hypertensives and 77 normotensives. The recruitment of these subjects was done in local Health Centers of the city of Oran, West Algeria. HTN was defined as elevated systolic blood pressure SBD≥140  mmHg and or sustained diastolic blood pressure DBP≥90  mmHg, measured using an Omron^® Automatic BP Monitor - M-3W machine. Consents were obtained from all participants. Polymerase chain reaction (PCR) combined with restrictive fragment length polymorphism (RFLP) was used to genotype the NOS -786T/C variant.

RESULTS

The distribution of the allelic frequencies did not differ between cases and controls (OR = 1.48; 95%CI [0.94-2.32], P = 0.09). However, after adjustment with the age, sex, and body mass index, we observed significant association between NOS -786C allele and HTN status (OR = 2.08; 95%CI [1.18-3.66], P = 0.01).

CONCLUSION

Our results indicate that the C allele of the NOS3 gene is associated with increased risk of essential hypertension in this sample of the Algerian population of the Oran city. Further validation in larger samples is needed to confirm this finding.

Increased arterial pressure in mice with overexpression of the ADHD candidate gene calcyon in forebrain

The link between blood pressure (BP) and cerebral function is well established. However, it is not clear whether a common mechanism could underlie the relationship between elevated BP and cognitive deficits. The expression of calcyon, a gene abundant in catecholaminergic and hypothalamic nuclei along with other forebrain regions, is increased in the brain of the spontaneously hypertensive rat (SHR) which is a widely accepted animal model of essential hypertension and attention deficit hyperactivity disorder (ADHD). Previous studies demonstrated that mice with up-regulation of calcyon in forebrain (CalOE) exhibit deficits in working memory. To date, there is no evidence directly connecting calcyon to BP regulation. Here, we investigated whether forebrain up-regulation of calcyon alters BP using radiotelemetry. We found that CalOE mice exhibited higher mean arterial pressure (MAP) compared to tTA controls. Plasma norepinephrine levels were significantly higher in CalOE mice compared to tTA controls. Silencing the transgene with doxycycline normalized BP in CalOE mice, whereas challenging the mice with 4% high salt diet for 12 days exacerbated the MAP differences between CalOE and tTA mice. High salt diet challenge also increased proteinuria and urinary thiobarbituric acid reactive substances (TBARs) in tTA and CalOE; and the increases were more prominent in CalOE mice. Taken together, our data suggest that upregulation of calcyon in forebrain could increase BP via alterations in noradrenergic transmission and increased oxidative stress during high salt challenge. Overall, this study reveals that calcyon could be a novel neural regulator of BP raising the possibility that it could play a role in the development of vascular abnormalities.

Predictive Models for the Risk of Dyslipidemia in Adolescents with Essential Arterial Hypertension

Predictive models of comorbidity, dyslipidemic disorders and essential arterial hypertension, in Russian adolescents aged 12 to 18 years (mean 15.48±1.53) were formulated with consideration for biochemical (lipid profiles) and genetic parameters (carrier state of gene polymorphic variants of apolipoprotein genes ApoA1 (-75G/A and +83C/T), ApoB (Ins/Del), ApoC3 (S1/S2), and ApoE (ε2/ε3/ε4). Significant prognostic risk factors for the mentioned comorbid pathologies were lipid metabolism parameters HDL-Ch, LDL-Ch, VLDL-Ch and carrier state of the +83T allele of the ApoA1 gene and Del allele of the ApoB gene. The obtained mathematical model is characterized by high predictive accuracy: the percentage of correct classification or the rate of correct assignment of each participant to the proper group was 96.33%.

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 polymorphism G894 T of endothelial nitric oxide synthase (eNOS) gene is associated with susceptibility to essential hypertension (EH) in Morocco

BACKGROUND

Hypertension is a multifactorial disease involving both environmental and genetic Factros. G894 T eNOS polymorphism has been suggested to be responsible for reduced NO synthesis, and EH development. The objective of our case-control study is to evaluate the potential association of G894 T eNOS polymorphism with Essential Hypertension (EH) susceptibility, among a sample of Moroccan patients.

METHODS

One hundred forty five hypertensive patients were recruited from the department of Cardiology, University Hospital Center Ibn Rochd, Casablanca, Morocco, and compared to 184 apparently healthy subjects. DNA samples were genotype by PCR-RFLP method using MboI restriction enzyme.

RESULTS

Our results showed a positive correlation between G894 T eNOS distribution and Alcohol and Obesity rik factors (P = 0.009 and 0.02 respectively). Patients with elevated Cardio Vascular Risk (CVR) carried out the higher frequency of homozygous mutant genotype TT (62.2%) and T mutant allele (77.8%), compared to median and low CVR groups. G894 T eNOS distribution was significantly associated to a high risk of EH occurrence under the GT and TT genotypes (OR [95% CI] = 20.2 [7.7-52.4], P <  0.0001; OR [95% CI] = 332.5 [98.2-1125.4], P <  0.0001 respectively), and the 3 genotypic transmission models (Dominant: OR [95% CI] = 43.2 [17.9-104.09], P <  0.0001; Recessive: OR [95% CI] = 47.7 [18.6-122.3]; P <  0.0001; Additive: OR [95% CI] = 14.02 [9.6-20.45], P <  0.0001).

CONCLUSION

Our study suggests a strong association of G894 T eNOS polymorphism with susceptibility to EH in Morocco. Studies trying to identify contributing genes may be very useful and allow recognizing the vulnerable individuals and classifying patients in subgroups with definite genetic and pathogenic mechanisms to achieve better prevention and therapeutics.

Association of with-no-lysine kinase 1 and Serine/Threonine kinase 39 gene polymorphisms and haplotypes with essential hypertension in Tibetans

Tibetans have a higher essential hypertension prevalence compared with other ethnics in China. The reason might be due to their unique environmental influence, as well as genetic factor. However, limited studies focus on Tibetan genetics and its association with hypertension. The aim of this study was to investigate the association between With-No-Lysine (K) Kinase 1 (WNK1), Serine/Threonine kinase 39(STK39) genes variants and hypertension in the Tibetan population. 204 Tibetan hypertensive patients and 305 normotensive controls were recruited in an epidemiological survey conducted at 2 sites in the Ganzi Tibetan autonomous region. Patients were genotyped for nineteen WNK1 candidate tag single nucleotide polymorphisms (SNPs) and three STK39 SNPs, and haplotype analysis was performed. Results showed that the allele A in rs1468326 was overrepresented in hypertensive patients versus control (53.4% vs 42.9%, P < 0.05). The multivariable-adjusted odds ratio (OR) for hypertension among CA + AA genotypes carriers was 1.60 (95% CI: 1.02-2.62, P < 0.05), and they also had a higher systolic blood pressure (136.5 ± 28.6 vs 131.7 ± 24.8 mmHg, P < 0.05). However, the TT genotype ratio in rs6749447 was lower in hypertensives (5.4% vs 10.8%, P < 0.05), and the hypertension risk for the TT genotype carriers in rs6749447 decreased after adjustment (OR 0.49, 95% CI 0.19-0.95, P < 0.05). Subjects with haplotype AGACAGGAATCGT showed 1.57 times higher risk of hypertension (95% CI 1.02-2.41, P < 0.05). In conclusion, SNP rs1468326 of WNK1, rs6749447 of STK39, and WNK1 haplotype AGACAGGAATCGT were associated with hypertension in Tibetan individuals. Environ. Mol. Mutagen. 59:151-160, 2018. © 2017 Wiley Periodicals, Inc.

[Association of sodium ion transporter gene polymorphisms with essential hypertension among ethnic Koreans from Mudanjiang]

OBJECTIVE To assess the association of SLC12A3 and SCNN1B gene polymorphisms (rs11643718 and rs12447134) with essential hypertension among ethnic Koreans from Mudanjiang, China. METHODS For 204 patients with essential hypertension and 186 healthy controls, the genotypes of rs11643718 and rs12447134 loci were determined with an improved multiplex ligase detection reaction (iMLDR) method. RESULTS Allelic and genotypic frequencies of rs11643718 of SLC12A3 gene are associated with the onset of disease hypertension (P <0.05) as well as systolic blood pressure (P < 0.01, under a recessive model). No association was found between rs12447134 of SCNN1B gene with the onset of disease (P > 0.05) but diastolic blood pressure (P < 0.05, under a recessive model). CONCLUSION The polymorphisms of rs11643718 locus is associated with the susceptibility for essential hypertension among ethnic Koreans from Mudanjiang area and can be used as a predictor for the disease.

A functional variant in ST2 gene is associated with risk of hypertension via interfering MiR-202-3p

Recent studies have suggested that interleukin 1 receptor-like 1 (ST2) plays a critical role in pathogenesis of several cardiovascular disease conditions. In this study, we examined association of 13 single nucleotide polymorphisms (SNPs) of ST2 gene with essential hypertension (EH) risk in 1151 patients with EH and 1135 controls. Our study showed that variants rs11685424, rs12999364 and rs3821204 are highly associated with an increase in risk of EH, while rs6543116 is associated with a decrease risk of EH. Notably, in silico analyses suggested the G>C change of rs3821204, which located within the 3'UTR of soluble ST2 mRNA, disrupted a putative binding site for miR202-3p. Functional analyses suggested that miR-202-3p significantly decreased soluble ST2-G mRNA stability and inhibited its endogenous expression. Furthermore, we found increased plasma-soluble ST2 (sST2) level was highly associated with CC genotype of rs3821204 in vivo. Taken together, our findings provide the first evidence that genetic variants in ST2 gene are associated with EH risk and variant rs3821204 may influence the development of EH by controlling sST2 expression.

[Effects of angiotensin-converting enzyme gene and environment interaction on essential hypertension in the Han nationality]

OBJECTIVE

To investigate the effects of angiotensin-converting enzyme( ACE) gene I/D and A2350 G polymorphisms with environmental factors interaction on essential hypertension in the Han nationality.

METHODS

A population-based case-control study was conducted, and 1010 patients with hypertension and 1030 normal controls were recruited from Lanxi Country rural, Heilongjiang Province. ACE gene two polymorphism sites were detected by polymerase chain reaction-restriction fragment length polymorphism( PCR-RFLP). Using multivariate Logistic regression to analysis the interaction between gene polymorphisms and environmental factors.

RESULTS

The distributions of ACE two polymorphism sites genotypes in control group were in accordance with the HardyWeinberg equilibrium( HWE). Multivariate Logistic analysis showed that age, gender, family history of hypertension, BMI, TG and high-density lipoprotein enter the model and were the risk factors for essential hypertension( P < 0. 05), especially, family history of hypertension( χ~2= 53. 488, OR = 2. 140, 95% CI 1. 746-2. 625). The interaction analysis between two sites genotype and environmental factors, noted that there were statistically significant combination effect between genotypes of the two sites and the factors of age, gender, BMI, TG and high-density lipoprotein. There was multiplication interaction only between I/D and age( P = 0. 0356, OR = 1. 021, 95% CI 1. 001-1. 021).

CONCLUSION

There are combination effect between ACE gene I/D and A2350 G polymorphisms with multiple environmental factors, which are likely to increase the risk of suffering from essential hypertension.

Association Analysis of FOXO3 Longevity Variants With Blood Pressure and Essential Hypertension

BACKGROUND

The minor alleles of 3 FOXO3 single nucleotide polymorphisms (SNPs)- rs2802292 , rs2253310 , and rs2802288 -are associated with human longevity. The aim of the present study was to test these SNPs for association with blood pressure (BP) and essential hypertension (EHT).

METHODS

In a primary study involving Americans of Japanese ancestry drawn from the Family Blood Pressure Program II we genotyped 411 female and 432 male subjects aged 40-79 years and tested for statistical association by contingency table analysis and generalized linear models that included logistic regression adjusting for sibling correlation in the data set. Replication of rs2802292 with EHT was attempted in Japanese SONIC study subjects and of each SNP in a meta-analysis of genome-wide association studies of BP in individuals of European ancestry.

RESULTS

In Americans of Japanese ancestry, women homozygous for the longevity-associated (minor) allele of each FOXO3 SNP had 6mm Hg lower systolic BP and 3mm Hg lower diastolic BP compared with major allele homozygotes (Bonferroni corrected P < 0.05 and >0.05, respectively). Frequencies of minor allele homozygotes were 3.3-3.9% in women with EHT compared with 9.5-9.6% in normotensive women ( P = 0.03-0.04; haplotype analysis P = 0.0002). No association with BP or EHT was evident in males. An association with EHT was seen for the minor allele of rs2802292 in the Japanese SONIC cohort ( P = 0.03), while in European subjects the minor allele of each SNP was associated with higher systolic and diastolic BP.

CONCLUSION

Longevity-associated FOXO3 variants may be associated with lower BP and EHT in Japanese women.

[Not Available]

The aim of the study was to evaluate the association between the angiotensin-converting enzyme ACE I/D (rs4340) polymorphism and DNA damage in pati-ents with essential hypertension (EH). The I/D polymorphism of ACE was determined by polymerase chain reaction in 170 male hypertensive patients and 64 normotensive blood donors. We used flow cytometry to determine the levels of cell death, micronuclei and accumulation of peripheral blood leukocytes in G1/G0, S, G2/M phases of the cell cycle. Additionally, the whole blood samples were incubated in vitro at 4 ºC for 24 h to investigate the genotype effects on the susceptibility of cells to DNA damage. We found lower frequency of cells in DNA synthesis S phase and higher levels of micronuclei in the hypertensive compared to normotensive group (p<0.05); increased formation of micronuclei was seen due to elevated micronuclei fre-quencies in patients with the ACE II genotype (p < 0.05), but not in ID or DD genotype carriers. Incubation of whole blood samples of normotensive individuals lead to the most active cell death (p < 0.05) and micronuclei formation (p > 0.05) in the II genotype carriers too. However, hypertensive patients displayed different cellular response to incubation-induced DNA damages in the ACE I/D genotype groups; after incubation, the frequencies of micronuclei were significantly higher in the DD genotype carriers (p < 0.05). To conclude, the study suggests that the ACE I/D polymorphism may contribute to mechanisms and intensity of DNA damages in hypertensive and normotensive individuals.

[Research on Association between Ataxia Telangiectasia Mutated(ATM)Gene Single Nucleotide Polymorphism Rs189037 C>T and Essential Hypertension]

This study aimed to explore the possible association between single nucleotide polymorphism(SNP)rs189037C>T in the promoter region of ataxia telangiectasia mutated(ATM)gene and essential hypertension(EH).We performed a case-control study to collect randomly 369 hospitalized patients aged 50 years and above.They were divided into EH group(190patients)and control group(179subjects)according to the diagnostic criteria of hypertension.The SNP rs189037 genotyping was performed using polymerase chain reaction-restriction fragment length polymorphism.The genotype frequencies of ATM gene polymorphism rs189037 for the whole sample were33.9% CC,48.0% CT,and 18.1% TT.There was no significant difference in the genotype frequency distributions of the SNP rs189037 between EH and control groups(P=0.619).After adjustment of the major confounding factors,the SNP rs189037 was still not associated with EH(P>0.05).We further analyzed data from different groups divided by genders and age respectively,and the relationship was retained(P>0.05).In addition,we found that the percentage of the TT genotype was much lower in coronary artery disease(CAD)patients than those in the CC or CT genotype(OR=0.49,95% CI=0.26~0.90,P=0.021).In conclusion,our study suggests that SNP rs189037 in the promoter of ATM gene is not associated with EH.But it is related to the incidence of CAD,and TT genotype seems to be a protective factor for CAD.

Assessment of mitochondrial DNA mutations in Chinese family with essential hypertension

Mitochondrial DNA (MtDNA) mutations played an important role in the development of essential hypertension. Mitochondrial tRNA point mutations, caused the failure in tRNA metabolism, responsible for the pathogenesis of this complex disease. In this study, we evaluated the possible role of the 4329C >G mutation in the clinical expression of hypertension in a Chinese family. Analysis of the complete mtDNA sequence variants showed that other mutations may play synergic roles in the phenotypic manifestation of hypertension. In addition, other potential pitfalls were also discussed in this context.