Endothelial NOS G894 T and MMP-3 5A/6A gene polymorphisms and hypertension in Serbian population

Signaling pathways in vascular function and hypertension: molecular mechanisms and therapeutic interventions

Hypertension is a global public health issue and the leading cause of premature death in humans. Despite more than a century of research, hypertension remains difficult to cure due to its complex mechanisms involving multiple interactive factors and our limited understanding of it. Hypertension is a condition that is named after its clinical features. Vascular function is a factor that affects blood pressure directly, and it is a main strategy for clinically controlling BP to regulate constriction/relaxation function of blood vessels. Vascular elasticity, caliber, and reactivity are all characteristic indicators reflecting vascular function. Blood vessels are composed of three distinct layers, out of which the endothelial cells in intima and the smooth muscle cells in media are the main performers of vascular function. The alterations in signaling pathways in these cells are the key molecular mechanisms underlying vascular dysfunction and hypertension development. In this manuscript, we will comprehensively review the signaling pathways involved in vascular function regulation and hypertension progression, including calcium pathway, NO-NOsGC-cGMP pathway, various vascular remodeling pathways and some important upstream pathways such as renin-angiotensin-aldosterone system, oxidative stress-related signaling pathway, immunity/inflammation pathway, etc. Meanwhile, we will also summarize the treatment methods of hypertension that targets vascular function regulation and discuss the possibility of these signaling pathways being applied to clinical work.

Association of MMP1 and MMP3 haplotypes with myocardial infarction and echocardiographic parameters of the left ventricle

BACKGROUND

Myocardial infarction (MI) leads to ischemia and afterward to left ventricular (LV) remodeling. Matrix metalloproteinase-1 (MMP1) and -3 (MMP3) belong to the family of endopeptidases and together they can dissolve most of the components of the extracellular matrix. MMP1 and MMP3 variants have been investigated solely in association with ischemic heart disease and LV dysfunction, but not in haplotype. The aims of this study were to investigate the association of haplotypes inferred from MMP1 rs1799750 (-1607 1G/2G; NC_000011.9:g.102670497del) and MMP3 rs35068180 (-1612 5A/6A; NC_000011.9:g.102715952dup) with MI and their effect on the change in echocardiographic parameters of LV structure and function in patients within 6 months after MI.

METHODS

The study included 325 patients with the first MI and 283 healthy controls. Gene variants were detected by PCR-RFLP method. Parameters of LV structure and function were assessed by conventional 2D echocardiography, 3-5 days and 6 months after the first MI, on a subgroup of 160 patients. Haplotype analysis was performed with Thesias software.

RESULTS

Haplotypes 2G-5A and 1G-6A were significantly and independently associated with MI compared with the reference haplotype 2G-6A (adjusted, p = 0.009 and p = 0.026, respectively). After Bonferroni correction for multiple testing, MMP1 and MMP3 haplotypes lost their association with the change in LV long diameter and stroke volume within 6 months after MI.

CONCLUSION

MMP1 and MMP3 haplotypes are strongly associated with MI. Further studies are needed to validate this result and to examine their association with echocardiographic parameters of LV structure and function after MI.

The Role of Single-Nucleotide Variants of NOS1, NOS2, and NOS3 Genes in the Comorbidity of Arterial Hypertension and Tension-Type Headache

Patients with tension-type headache (TTH) have an increased risk of developing arterial hypertension (AH), while hypertensive subjects do seem to have an increased risk of TTH. We searched for full-text English publications in databases using keywords and combined word searches over the past 15 years. In addition, earlier publications of historical interest were included in the review. In our review, we summed up the single nucleotide variants (SNVs) of Nitric Oxide Synthases (NOSs) genes involved in the development of essential AH and TTH. The results of studies we discussed in this review are contradictory. This might be due to different designs of the studies, small sample sizes in some of them, as well as different social and geographical characteristics. However, the contribution of genetic and environmental factors remains understudied. This makes the issue interesting for researchers, as understanding these mechanisms can contribute to a search for new approaches to pathogenetic and disease-modifying treatment of the AH and TTH phenotype. New drugs against AH and TTH can be based on inhibition of nitric oxide (NO) production, blockade of steps in the NO-cGMP pathway, or NO scavenging. Indeed, selective neuronal NOS (n-NOS) and inducible NOS (i-NOS) inhibitors are already in early clinical development.

Study of associations of polymorphism of matrix metalloproteinases genes with the development of arterial hypertension in men

The aim of research. To study the association of polymorphic loci of matrix metalloproteinases with the development of essential hypertension (EH) in men of the Central Chernozem Region of Russia. Materials and methods. A study of 564 men with EH and 257 control men was performed. Analysis of the polymorphic loci of metalloproteinases rs11568818 MMР7, rs1320632 MMР8, rs11225395 MMР8, rs1799750 MMР1, rs3025058 MMР3 was performed using real-time PCR. The study of associations of SNPs and their haplotypes with the development of arterial hypertension was carried out using logistic regression analysis in the PLINK software (v. 2.050). The regulatory potential of polymorphic loci was analyzed in the HaploReg software (v. 4.1) (http://archive.broadinstitute.org). The effect of SNP on gene expression was studied using the data of the Genotype-Tissue Expression project (http://www.gtexportal.org/). Results. Haplotype including rs11568818 MMP7, rs1320632 MMP8, rs11225395 MMP8 and rs1799750 MMP1 associated with a high risk of disease in men (OR=2,58, pperm=0,04). These polymorphisms located in region of promoter and enhancer histone marks and in the region of hypersensitivity to DNAse-1. They located in sites of proteins bound (TBP, CJUN, CFOS and GATA2) and they associated with the level of gene expression ММР7, ММР27 and RP11-817J15.3 (in peripheral blood, skeletal muscles, nervous tissue and other). Сonclusion. Haplotype G-A-C-1G for polymorphisms rs11568818 MMP7, rs1320632 MMP8, rs11225395 MMP8, rs1799750 MMP1 are associated with the development of essential hypertension in men in the Central Chernozem Region of Russia.

Polymorphic locus rs652438 of the MMP12 gene is associated with the development of hypertension in women

Objective.To study the association of polymorphic loci rs243865 MMP2, rs17577 MMP9, rs652438 MMP12 with the development of arterial hypertension (HTN) in women of the Central Chernozem Region of Russia.

Design and methods.A total of 584 women were examined: 375 HTN patients and 209 controls. Analysis of the polymorphic loci of metallоproteinases was performed using real-time polymerase-chain reaction (PСR). Statistical analysis was carried оut using software “STATISTICA for Windows 10.0”. The prediсtive value of the non-synоnymous single nucleotide polymorphism (SNP) wаs estimatеd using the Sorting Tolerant From Intоlerant software (http://sift.jcvi.org/). The regulatorу potential of polymоrphic loci was analyzеd in the HaplоReg software (v4.1) (http://archive.brоаdinstitute.оrg). The effect of SNP on gene expression was studied using thе data of the Genоtype-Tissue Expressiоn project (http://www.gtexportal.оrg/).

Results.We found an association of the locus rs652438 MMP12 with the occurrence of HTN in women. Polymorphic variant G (odds ratio (OR) = 1,86, 95 % confdence interval (CI) = 1,02–3,45, p = 0,04) and genotype GA (OR = 2,04, 95 % CI = 1,06–3,98, p = 0,03) of rs652438 are associated with the high risk of HTN development. The genotype AA rs652438 demonstrates a protective effect regarding the risk of HTN occurrence (OR = 0,50, 95% CI = 0,26–0,95, p = 0,03). We assume that the epigenetic effects of rs652438 MMP12 underlie the identifed associations. The locus rs652438 MMP12 is nsSNP and has a SIFT Score = 0,01. This polymоrphism is lоcated in histоnes regiоn marking prоmoters (H3K9 ас) and enhаncers (H3K4me1, H3K27 ас). The locus is in linkage disequilibrium (r 2 = 0,95) with SNP that affect the expression level of the MMP12 gene

MMP-1 and -3 haplotype is associated with congenital anomalies of the kidney and urinary tract

BACKGROUND

Congenital anomalies of the kidney and urinary tract (CAKUT) are a common cause of progressive chronic kidney disease that may lead to end-stage renal disease and renal replacement therapy in childhood. Altered expression or activity of matrix metalloproteinases (MMPs) have been found in CAKUT. The MMP-1, -3, and -8 polymorphisms studied here are located in the gene promoters and alter expression. Our aim was to investigate associations of MMP polymorphisms, solely and in haplotypes, with CAKUT in children.

METHODS

A case-control study with 101 pediatric patients and 281 controls was performed. The MMP-1 (-1607 1G/2G), -3 (5A/6A), and -8 (-799 C/T) genotypes were determined by PCR-restriction fragment length polymorphism.

RESULTS

We found statistically significant associations of MMP-3 5A/6A polymorphism (p < 0.0001) and 1G-(1607)-6A haplotype, with no preferences for MMP-8 -799C or T alleles, with CAKUT (OR = 2.93, 95 % CI 1.43-5.98, adjusted for gender, p = 0.003) and with obstructive uropathies in a subgroup of patients (OR = 4.57, 95 % CI 2.74-7.61, adjusted for gender, p < 0.0001).

CONCLUSIONS

MMP-3 genotypes and MMP-3 and -1 haplotypes encompassing either MMP-8 -799C or T alleles were associated with CAKUT and obstructive uropathies in pediatric patients. Still, functional and association studies are needed to elucidate evident roles of MMPs in CAKUT.

Variants of endothelial nitric oxide synthase gene are associated with components of metabolic syndrome in an Arab population

Genetics plays a crucial role in the development of metabolic syndrome (MetS). Here we examined the association between endothelial nitric oxide synthase (eNOS) gene polymorphisms and MetS in a Saudi Arabian cohort to extend the understanding of the genetic basis of MetS in diverse ethnic populations. Anthropometric, clinical and biochemical parameters as well as genotyping for 894G>T, -786T>C variants of eNOS gene by PCR-RFLP and 4a/b by direct PCR were performed in 886 Saudi Arabians (477 MetS and 409 Non-MetS). The genotype distribution (TT, p=0.001; TC, p=0.001; TC+CC, p=0.001) and allele (T, p=0.007; C, p=0.007) frequency of the -786T>C SNP were significantly different between Non-MetS and MetS subjects which remained significant after Bonferroni correction. Moreover: 1) the GT and GT+TT genotypes of the 894G>T SNP were associated with elevated blood pressure (p=0.017, and p=0.022, respectively); 2) the ab variant of 4a/b polymorphism was associated with decreased HDL levels (p= 0.044); and 3) the TC+CC genotype and C allele of the -786T>C SNP were associated with increased fasting glucose levels (p=0.039, and p=0.028, respectively). Also, G-a-C was identified as the risk haplotype for MetS susceptibility (p=0.034). The results suggest a significant association of 894G>T, 4a/b and -786T>C polymorphisms with MetS and its components is present in an Arab population. A genetic predisposition to develop abnormal metabolic phenotypes, consistent with an increased prevalence of metabolic phenotypes can be detected in this ethnic group.

An updated meta-analysis of endothelial nitric oxide synthase gene: three well-characterized polymorphisms with hypertension

Background

Numerous individually underpowered association studies have been conducted on endothelial nitric oxide synthase (eNOS) genetic variants across different ethnic populations, however, the results are often irreproducible. We therefore aimed to meta-analyze three eNOS widely-evaluated polymorphisms, G894T (rs1799983) in exon 7, 4b/a in intron 4, and T−786C (rs2070744) in promoter region, in association with hypertension from both English and Chinese publications, while addressing between-study heterogeneity and publication bias.

Methods

Data were analyzed using Stata software (version 11.0), and random-effects model was applied irrespective of between-study heterogeneity, which was evaluated by subgroup and meta-regression analyses. Publication bias was weighed using the Egger's test and funnel plot.

Results

There were total 19284/26003 cases/controls for G894T, and 6890/6858 for 4b/a, and 5346/6392 for T−786C polymorphism. Overall comparison of allele 894T with 894G in all study populations yielded a 16% increased risk for hypertension (odds ratio [OR] = 1.16; 95% confidence interval [95% CI]: 1.07–1.27; P = 0.001), and particularly a 32% increased risk (95% CI: 1.16–1.52; P<0.0005) in Asians and a 40% increased risk (95% CI: 1.19–1.65; P<0.0005) in Chinese. Further subgroup analyses suggested that published languages accounted for the heterogeneity for G894T polymorphism. The overall OR of allele 4a versus 4b was 1.29 (95% CI: 1.13–1.46; P<0.0005) in all study populations, and this estimate was potentiated in Asians (OR = 1.42; 95% CI: 1.16–1.72; P<0.0005). For T−786C, ethnicity-stratified analyses suggested a significantly increased risk for −786C allele (OR = 1.25; 95% CI: 1.06–1.47; P = 0.007) and −786CC genotype (OR = 1.69; 95% CI: 1.20–2.38; P = 0.003) in Whites. As an aside, the aforementioned risk estimates reached significance after Bonferroni correction. Finally, meta-regression analysis on other study-level covariates failed to provide any significance for all polymorphisms.

Conclusion

We, via a comprehensive meta-analysis, ascertained the role of eNOS G894T and 4b/a polymorphisms on hypertension in Asians, and T−786C polymorphism in Whites.

Association of MMP-3 5A/6A gene polymorphism with susceptibility to carotid atherosclerosis

OBJECTIVES

Stromelysin-1 (MMP-3) as a key member of metalloproteinase family could have an important role in atherogenesis. The 5A/6A polymorphism in the promoter of MMP-3 gene affects the level of MMP-3 gene expression. We assessed whether the MMP-3 promoter low- and high-activity genotypes are related to susceptibility for carotid atherosclerosis (CA) in Serbian population.

DESIGN AND METHODS

The study group of case-control design consisted of 515 participants. The 265 patients with ultrasonographic evidence of carotid plaque presence were recruited for the study. The 5A/6A polymorphism was typed by RFLP-PCR.

RESULTS

There was significantly higher prevalence of genotypes containing 6A allele in the patients with CA compared to controls (p<0.05). The model of inheritance with the dominant effect of 6A allele gave elevated and significant OR for carotid atherosclerosis (adjusted OR 2.35, CI=1.0-5.5, p=0.048).

CONCLUSIONS

Subjects carrying genotypes with 6A allele had significantly higher susceptibility to carotid atherosclerosis.

Association of the MMP-3 5A/6A gene polymorphism with multiple sclerosis in patients from Serbia

Matrix metalloproteinases (MMPs) are proteolytic enzymes involved in remodeling of the extracellular matrix. MMPs are suggested to play a role in the influx of inflammatory cells into the CNS, disruption of the blood brain barrier, and to degrade myelin in vitro. In this study, we have investigated the possible association of MMP-3 5A/6A gene polymorphism with MS susceptibility and/or severity in patients from Serbia. A total of 184 MS patients (150 RR, 34 SP) and 236 controls have been studied. Results show that the distribution of MMP-3 5A/6A genotype frequencies between MS patients and controls were not significantly different. In bout onset patients, carriers of MMP-3 6A/6A genotype had significantly higher mean MSSS values compared to the carriers of 5A allele (6.29+/-1.89 vs. 5.29+/-2.62, respectively, ANCOVA, p=0.01 Scheffe post-hoc test). In conclusion, our results indicate association of MMP-3 6A/6A genotype with significantly higher mean MSSS values. Thus, the obtained results suggest that it should be carefully considered during follow up of patients with MS. Further genetic and functional studies are needed to resolve the complex role of MMPs and their tissue inhibitors in MS pathology and/or regeneration.

Three endothelial nitric oxide (NOS3) gene polymorphisms in hypertensive and normotensive individuals: meta-analysis of 53 studies reveals evidence of publication bias

BACKGROUND

Studies on the relationship between endothelial nitric oxide (NOS3) gene variants and hypertension have been conflicting. To explore this hypothesis further, we performed a meta-analysis and re-evaluated the relationship between the three most widely studied NOS3 polymorphisms and hypertension status and blood pressure levels.

METHODS

Data on 40,413 subjects from 53 studies were combined in five distinct meta-analyses, and heterogeneity and publication bias were explored.

RESULTS

Heterogeneity was observed in all meta-analyses. By a random-effects model, carriers of the four 27-basepair repeat variable number of tandem repeats in intron 4 were associated with a 28% increase in the risk of hypertension compared with those homozygous for the 5 repeat: odds ratio (OR) 1.28, 95% confidence interval (CI) 1.11-1.47, P=0.001. In Asian individuals, Asp allele carriers displayed a similar association: OR 1.28, 95% CI 1.06-1.54, P=0.01, as well as a 2 mmHg increase in both systolic (P=0.04) and diastolic (P=0.009) blood pressure levels. Furthermore, meta-regression analysis indicated that the effect of the Glu298Asp genotype on the risk of hypertension might be dependent on total cholesterol status. No effect of the T-786C variant on hypertension was detected. There was evidence that such findings might be a result of selectively reporting/publishing positive reports.

CONCLUSION

Our results suggest that current data on the relationship between NOS3 variants and hypertension are subject not only to important heterogeneity but also to publication bias. Future research should preferentially focus on gene-environment interactions as well as haplotype analyses.

Endothelial NO synthase gene polymorphisms and hypertension: a meta-analysis

Studies investigated the association between endothelial NO synthase gene polymorphisms and hypertension-reported contradicted or nonconclusive results. A meta-analysis of 35 genetic association studies that examined the relation between hypertension and the G894T, 4a/b, T786C, and G23T polymorphisms of the endothelial nitric oxide synthase gene was carried out. Subgroup analysis by ethnicity and potential sources of heterogeneity and bias were explored. The meta-analysis included genotype data on 7779/10 498, 2216/3222, 2491/3913, and 833/587 cases/controls for G894T, 4b/a, T786C, and G23T, respectively. For the 4b/a polymorphism, overall, the heterogeneity between studies was not significant (P=0.82), and the allele b was associated with a 15% decreased risk of hypertension relative to allele a (odds ratio: 0.85; 95% CI: 0.74 to 0.98). Overall and in whites, the recessive model for allele b produced significant results (odds ratios: 0.78; 95% CI: 0.68 to 0.90 and OR: 0.76 95% CI: 0.62 to 0.92, respectively), whereas the dominant model produced nonsignificant results. In studies involved East Asians and blacks, an association was not demonstrated. Regarding the G894T, T768C, and G23T polymorphisms, in no case (ie, overall, in whites, or in East Asians) was a statistically significant association and heterogeneity found. There was no substantial source of bias in the selected studies. In conclusion, there is evidence of association only between 4b/a polymorphism and hypertension; however, studies exploring combinations of the polymorphisms may help us better understand the genetics of hypertension.

Risk factors of atherosclerosis: A review of genetic epidemiology data from a Serbian population

Determining common risk factors for the onset and progression of atherosclerosis and cardiovascular diseases, which are known to be multi-factorial and polygenic diseases, represents a challenge for medicine in the future. In recent years, there have been breakthroughs in the determination of pathogenesis, risk estimating methodologies, modifications of genetic risk in prophylaxis and in establishing new therapeutic targets in pharmacology. The role of genetic epidemiology is to provide necessary data about genetic characteristics of different populations, as well as gene-gene and gene-environment interactions, that lead to the development of diseases. The aim is to define high-risk haplotypes and primary targets for a new generation of pharmaceutical products and tools designed for the diagnosis and therapy of these disorders. The present review provides examples from the authors' genetic epidemiology studies regarding the association of candidate genes with risk factors of atherosclerosis, such as dyslipidemias, hypertension and diabetes mellitus, in a Serbian population, along with basic assumptions that come with this type of research. The main results of these studies are discussed, as well as problems that should be taken into consideration in future evaluations of disease risk in a population.