Gender specific association of endothelial nitric oxide synthase gene (Glu298Asp) polymorphism with essential hypertension in a south Indian population

Association of endothelial nitric oxide synthase (Glu298Asp) gene polymorphism with radial artery spasm during cardiac catheterization in Egyptians

BACKGROUND

Nitric oxide (NO) exerts diverse effects on the cardiovascular system. Impairment of NO production plays a key role in cerebral and coronary artery spasm. We aimed to explore the predicting factors of radial artery spasm (RAS) and the association of eNOS gene polymorphism (Glu298Asp) with RAS during cardiac catheterization.

METHODS AND RESULTS

200 patients underwent elective coronary angiography through a trans-radial approach. The subjects were genotyped to the Glu298Asp polymorphism (rs1799983) on the eNOS gene by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Our results showed that the subjects with the TT genotype and T allele were significantly more likely to develop radial artery spasms (OR = 12.5, 4.6, P < 0.001 respectively). TT genotype of eNOS Glu298Asp polymorphism, number of punctures, size of the radial sheath, radial tortuosity, and right radial access are independent predictors of radial spasm.

CONCLUSION

The eNOS (Glu298Asp) gene polymorphism is associated with RAS during cardiac catheterization in Egyptians. TT genotype of eNOS Glu298Asp polymorphism, number of punctures, size of the radial sheath, right radial access, and tortuosity are independent predictors of RAS during cardiac catheterization.

Endothelial nitric oxide synthase Asp298Glu (894G/T) gene polymorphism as a possible risk factor for the coronary slow flow phenomenon among Iranians

Background

Mounting evidence indicates an association between endothelial dysfunction and the coronary slow flow phenomenon (CSFP). In the present study, we aimed to evaluate the possible role of endothelial nitric oxide synthase (eNOS) 894G/T and interleukin-1β (IL-1β) 315C/T polymorphisms as possible risk factors for CSFP.

Methods

This prospective study enrolled patients with CSFP and individuals with normal coronary arteries. Genotypes were assessed using regular polymerase chain reaction and direct Sanger-sequencing techniques.

Results

The study population consisted of 267 individuals: 180 patients with CSFP (49 women [27.2%]) at a median age of 55 (48–62) years and 87 controls with normal coronary arteries (56 women [64.4%]) at a median age of 47 (41–58) years. The allelic distribution of eNOS 894G/T was significantly associated with CSFP (odds ratio [OR], 1.58; 95% confidence interval (CI), 1.04–2.42; P = 0.03). This polymorphism increased the risk of CSFP under the dominant model (OR 1.73; 95% CI I.02–2.95; P = 0.04). However, the allelic frequencies (1.05; 95% CI 0.68–1.59; P = 0.83) and genotypic frequencies (0.88; 95% CI 0.52–1.49; P = 0.63) of the IL-1β 315C/T polymorphism were not associated with the incidence of CSFP in the Iranian population.

Conclusions

The CSFP and control groups were statistically different regarding the eNOS 894G/T polymorphism. Our findings also demonstrated that the IL-1β 315C/T polymorphism was not a risk factor for CSFP.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-022-02736-0.

Endothelial nitric oxide synthase gene polymorphisms are associated with cardiovascular risks in prehypertensives

Though endothelial nitric oxide synthase (eNOS) gene polymorphism is documented in the causation of hypertension, its role in prehypertension has not been investigated. The present study was conducted in 172 subjects divided into prehypertensives (n = 57) and normotensives (n = 115). Cardiovascular (CV) parameters including baroreflex sensitivity (BRS) by continuous BP variability assessment and sympathovagal imbalance (SVI) by heart rate variability analysis were recorded. Biochemical parameters for insulin resistance (homeostatic model for assessment of insulin resistance), oxidative stress, lipid risk factors, renin, and inflammatory parameters were measured. Genotyping for eNOS polymorphisms rs1799983 (298G>T) and rs2070744 (-786T>C) was performed by polymerase chain reaction-restriction fragment length polymorphism method. Multiple regression analysis was done to assess the association between SVI and metabolic markers, and multivariate logistic regression was done to determine the prediction of prehypertension status by genotype, BRS, and ratio of low-frequency to high-frequency in these subjects. The BP variability, heart rate variability, and biochemical parameters were significantly altered in prehypertensives. The eNOS polymorphisms were found to be associated with prehypertension. BRS, the marker of SVI, was significantly associated with BP, homeostatic model for assessment of insulin resistance, and tumor necrosis factor alpha in 298GG genotype of prehypertensive population. The eNOS gene polymorphisms appear to be associated with prehypertension. 298G>T and -786T>C contribute to SVI in young prehypertensives attributed by insulin resistance and inflammation. The CV risks were associated with prehypertension status in prehypertensives expressing both 298GG and -786TT genotypes. Association of CV risks with SVI appears to be stronger in prehypertensives expressing GG genotype.

Association of endothelial nitric oxide synthase (eNOS) gene G894T polymorphism with hypertension risk and complications

This study evaluated the association of NOS3 polymorphisms with hypertension risk and complications. eNOS (G894T) SNP was performed by RT-PCR on 70 hypertensive patients (25 were hypertensive, 25 were hypertensive with CAD, and 20 were diabetic with hypertension) and 30 age- and gender-matched individuals. Lipid and glucose profile were assessed by standard colorimetric assay. Our results revealed that combination of (GT + TT) genotype and T allele significantly increases the risk of hypertension (OR = 3.86 and 4.33), respectively. Subgroup analysis showed significant association between CAD with eNOS (G894T) mutant genotype (P = 0.002) and allele frequency (P < 0.001). Moreover, the mutant homozygous and heterozygous eNOS genotype together were significantly associated with higher TC, LDLc, (P < 0.001), and TG (P = 0.001). Thus, hypercholesterolemia (P < 0.001 and OR = 12.48) increases the risk of hypertension among T carrier. These results indicated that the T carriers significantly increase hypertension risk and complication (CAD), mainly with hypercholesterolemia and in elderly.

Genetic epidemiology of coronary artery disease: an Asian Indian perspective

Coronary artery disease (CAD) has emerged as a major cause of morbidity and mortality worldwide. Recent findings on the role of genetic factors in the aetiopathology of CAD have implicated novel genes and variants in addition to those involved in lipid and lipoprotein metabolism. However, our present knowledge is limited due to lack of clarity on their exact identity and the quantum of impact on disease susceptibility, and incident risk. It is a matter of great interest to understand the role of genetic factors in ethnic populations that have a strong underlying predisposition to CAD such as the South Asian populations, particularly among Asian Indians living in India and abroad. Although, a number of isolated studies do implicate certain gene polymorphisms towards enhanced disease susceptibility, the available data remains scanty and inconclusive as they have not been validated in large, prospective cohorts. The present review aims to consolidate the available literature on the genetics of CAD in Asian Indians and seeks to provide insights on the concerns that need to be addressed in future studies to generate information having clinical value.

Gender-Specific Association of ATP2B1 Variants with Susceptibility to Essential Hypertension in the Han Chinese Population

Previous genome-wide association studies (GWASs) found that several ATP2B1 variants are associated with essential hypertension (EHT). But the "genome-wide significant" ATP2B1 SNPs (rs2681472, rs2681492, rs17249754, and rs1105378) are in strong linkage disequilibrium (LD) and are located in the same LD block in Chinese populations. We asked whether there are other SNPs within the ATP2B1 gene associated with susceptibility to EHT in the Han Chinese population. Therefore, we performed a case-control study to investigate the association of seven tagSNPs within the ATP2B1 gene and EHT in the Han Chinese population, and we then analyzed the interaction among different SNPs and nongenetic risk factors for EHT. A total of 902 essential hypertensive cases and 902 normotensive controls were involved in the study. All 7 tagSNPs within the ATP2B1 gene were retrieved from HapMap, and genotyping was performed using the Tm-shift genotyping method. Chi-squared test, logistic regression, and propensity score analysis showed that rs17249754 was associated with EHT, particularly in females. The MDR analysis demonstrated that the interaction of rs2070759, rs17249754, TC, TG, and BMI increased the susceptibility to hypertension. Crossover analysis and stratified analysis indicated that BMI has a major effect on the development of hypertension, while ATP2B1 variants have a minor effect.

Association of endothelial nitric oxide synthase Glu298Asp gene polymorphism in psoriasis cases with hypertension

BACKGROUND AND OBJECTIVES

Psoriasis is a common autoimmune-mediated chronic, inflammatory skin disease. Although, the molecular mechanism is not completely understood, psoriasis is caused by genetic and non-genetic parameters. The current study aimed (1) to define genotype and allele frequency of endothelial nitric oxide synthase (eNOS Glu298Asp) gene polymorphism in hypertensive and/or non-hypertensive psoriatic patients (2) to investigate the possible relationship between the eNOS Glu298Asp polymorphism and the risk of hypertension among psoriatic patients in the Turkish population.

DESIGN AND SETTINGS

This cross-sectional, case-control study was performed between March 2010 and November 2012 at the University hospital in Çanakkale, Turkey Patients and Methods: Gene profiles of 75 psoriatic patients (21 hypertensive and 54 normotensive pa.tients) and 55 healthy (normotensive and non-psoriatic) volunteers were compared. Peripheral blood-EDTA samples were used for total genomic DNA isolation and genotyping. Target eNOS gene was genotyped for patients and control groups by real-time PCR melting-curve analysis system (LightCycler 2.0,Roche, Germany, and results were compared statistically.

RESULTS

An increased T allele frequency in eNOS Glu298Asp single-nucleotide polymorphism (SNP) was determined in psoriatic patients when compared with normotensive non-psoriatic healthy volunteers (OR 2.3, CI 1.14-3.99), (P=.017). The T allele frequency was also found to be increased in hypertensive psoriatic patients when compared with healthy volunteers (4.83-fold increased, 95% CI 1.62-14.43 ([P=.003]) and normotensive psoriatic patients (3.03-fold increased, 95% CI 1.03-8.94 [P=.041]), respectively.

CONCLUSION

The current preliminary results suggested that there was a correlation between eNOS Glu298Asp polymorphism and hypertension among psoriatic patients in the Turkish population. The T allele frequency of eNOS Glu298Asp SNP was different in hypertensive psoriatic patients, and the difference was statistically significant when compared with the normotensive psoriatic patients and healthy controls. These results need to be confirmed by large-scale studies.

Genetic association of rs1800780 (A→G) polymorphism of the eNOS gene with susceptibility to essential hypertension in a Chinese Han population

To investigate the association of eNOS gene polymorphism with essential hypertension in the Chinese Han population, we examined polymorphisms of the rs2070744 (T→C), rs1800780 (A→G), and rs3918181 (A→G) loci. The results demonstrated that the genotypic frequency at the rs1800780 (A→G) locus was significantly different between patients with essential hypertension and the control cohorts (P < 0.05); while genotypic frequencies and allelic frequencies at rs2070744 (T→C) and rs3918181 (A→G) loci had no statistical difference between the patient group and controls (P > 0.05). In addition, haplotype analysis found a statistically significant difference for haplotype TGA, with OR (95% CI) of 1.549 (1.116-2.150) (P < 0.05). These findings suggest that polymorphism of rs1800780 (A→G) in the eNOS gene may be one of the most important genetic factors associated with essential hypertension susceptibility, and those who have haplotype TGA may be at risk to develop essential hypertension.

Effect of eNOS polymorphisms on salbutamol evoked endothelium dependent vasodilation in South Indian healthy subjects

BACKGROUND

The model of pulse plethysmograph using inhalational salbutamol 400 mcg is studied well to assess endothelium dependent vasodilation. Endothelial nitric oxide synthase (eNOS) gene polymorphism may influence the response to salbutamol in healthy subjects.

AIM

To find the effect of polymorphisms 894G>T and -786T>C of eNOS gene on endothelium dependent vasodilation in healthy subjects.

MATERIALS AND METHODS

One hundred and two south Indian healthy subjects of either sex, aged between 18 to 35 years were recruited for the study. The digital volume pulse (DVP)was measured by pulse plethysmograph before and after salbutamol 400mcg inhalation. Three predose and five postdose recordings of DVP were measured. The average change in the DVP parameters namely reflection index (RI) and stiffness index (SI) were determined. The eNOS894G>T and -786T>C gene polymorphism were genotyped using polymerase chain reaction followed by restriction fragment length polymorphism. The percentage changes in RI and SI from predose baseline recordings were calculated and compared between the genotype groups.

RESULTS

The genotype and allele frequency of study subjects were in Hardy-Weinberg equilibrium. The changes in DVP parameters were not significantly different between the genotype groups.

CONCLUSION

eNOS polymorphism do not affect salbutamol evoked endothelium dependent vasodilation in the model of pulse plethysmograph in healthy subjects.

Prevalence of endothelial nitric oxide synthase E298D polymorphism in Turkish patients with essential hypertension

AIMS

Our aim was to evaluate the effects of endothelial nitric oxide synthase (eNOS) E298D polymorphism in obesity variables and essential hypertension (eHT) development risk. The genotype frequencies of E298D polymorphism in eHT patients and non-hypertensive (non-HT) controls (proven to have normal coronaries angiographically) were analyzed for their association with demographic and obesity related data of the eHT patients and controls.

MATERIALS AND METHODS

eNOS gene E298D genotypes were determined with qPCR.

RESULTS

The eNOS E298D polymorphism frequencies for 298E/E, 298E/D and 298D/D genotypes were respectively as 41.1%, 44.6%, 14.3% in subjects eHT and 52.8%, 38.9%, 8.3% in the non-HT groups. The combined E298D homozygous polymorphic and heterozygous genotypes were found to have a decreasing effect on serum total-cholesterol levels in comparison to wild-type genotypes in eHT patients but not controls.

CONCLUSIONS

Our results support the idea that, the eNOS E298D polymorphism, which is not associated with hypertension, may increase the risk of hypertension when associated with high serum total-cholesterol levels.

The effects of hazardous chemical exposure on cardiovascular disease in chemical products manufacturing workers

The purpose of this study was to understand the mechanism of cardiovascular disease (CVD) caused by exposure to hazardous chemicals. We investigated changes in the symptoms of metabolic syndrome, which is strongly related to CVD, and in levels of other CVD risk factors, with a special emphasis on the roles of catecholamines and oxidative stress. The results revealed that neither body mass index (BMI) nor waist and hip circumferences were associated with exposure to hazardous chemicals. Among metabolic syndrome criteria, only HDL-cholesterol level increased on exposure to hazardous chemicals. Levels of epinephrine (EP) and norepinephrine (NEP) were not influenced by exposure to hazardous chemicals; however, the total antioxidative capacity (TAC) reduced because of increased oxidative stress. Both hazardous chemical exposure level and metabolite excretion were related to EP, NEP, and the oxidative stress index (OSI). Logistic regression analysis with these factors as independent variables and metabolic syndrome criteria as dependent variables revealed that EP was associated with blood pressure, and NEP with metabolic syndrome in the chemicalexposed group. In conclusion, the results suggest that reactive oxygen species generated and oxidative stress due to exposure to hazardous chemicals act as mediators and cause changes in the physiological levels of EP and NEP to increase blood pressure. This ultimately leads to the development of CVD through increase in cholesterol, triglyceride, and blood glucose levels by lipid peroxidation.

Endothelial nitric oxide synthase gene polymorphisms and the risk of acute myocardial infarction in a South Indian population

Myocardial infarction (MI) is a complex multi-factorial, polygenic disorder which results from an interaction between a person's genetic makeup and various environmental factors. Nitric oxide (NO), a potent vasodilator produced by endothelial cells, plays an important role in the regulation of blood pressure, regional blood flow and also inhibits platelet aggregation, vascular smooth muscle cell proliferation and leukocyte adhesion to vascular endothelium. Our aim was to analyze the association of NOS3 (endothelial nitric oxide synthase 3) 894G>T and -786T>C gene polymorphisms and MI risk in the South Indian population. A total of 287 MI patients, 279 risk control patients and 321 healthy controls were recruited for the retrospective study. Genotyping was done using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). There was no significant association observed between NOS3 894G>T, -786T>C polymorphisms and MI. A significant difference was observed in the distribution of GT genotype of the NOS3 894G>T polymorphism between the cases and the risk controls (p = 0.05) but the odds ratio (0.6) did not show risk for MI. The present study showed lack of association between NOS3 gene polymorphisms and MI in South Indian population.

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.

Endothelial nitric oxide synthase G894T gene polymorphism and essential hypertension in the Chinese population: a meta-analysis involving 11,248 subjects

BACKGROUND

The endothelial nitric oxide synthase (eNOS) G894T gene polymorphism has been suggested to be linked to the risk of essential hypertension (EH), however the results are still debatable.

OBJECTIVE AND METHODS

To assess the association between eNOS G894T gene polymorphism and EH, such electronic databases as Pubmed, Embase, Web of Science, China Biological Medicine Database (CBMD) and China National Knowledge Infrastructure (CNKI) were searched. The selection criteria were as follows: a) Evaluation of the association of eNOS G894T gene polymorphism and EH. b) EH diagnosis in compliance with EH diagnosis criteria of the World Health Organization (WHO) in 1999. c) The study results were in line with the Hardy-Weinberg equilibrium (HWE). In 23 separate studies with 11,248 subjects the relation between eNOS G894T gene polymorphism and EH was analyzed by current meta-analysis. Random effect model was used to calculate the pooled odds ratio (ORs) and its corresponding 95% confidence interval (95% CI).

RESULTS

In this eNOS G894T gene polymorphism and EH meta-analysis in the Chinese population, the distribution of T allele frequency was 0.154 for EH group and 0.128 for the control group. A significant association was found between G894T gene polymorphism and EH (p=0.0007). The pooled OR for the distribution frequency of T allele was 1.33 (95% CI:1.13-1.56, P(heterogeneity) <0.00001). In the stratified analysis by ethnicity, there was a significant association in Han subgroup (p=0.005). The pooled OR for the distribution frequency of T allele was 1.31 (95% CI:1.09-1.59, P(heterogeneity) <0.00001). No significant increased risk for EH was found in the non-Han subgroup (p=0.08).

CONCLUSION

In the current meta-analysis, T allele of eNOS G894T gene was suggested to be related to the increased risk of EH in the Chinese population, particularly in those of Han ethnicity.

Association between 894G>T endothelial nitric oxide synthase gene polymorphisms and metabolic syndrome

Metabolic syndrome (MS) is a cluster of cardiovascular risk factors such as hypertension, dyslipidemia, obesity and type II diabetes. Here, we performed a case-control study analyzing the association between 894G>T endothelial nitric oxide synthase gene polymorphism (NOS3) and MS in 616 subjects. Genotype frequencies were TT= 9.3%, GG= 37.2 and TG= 53.6% and the allelic frequencies were T=0.36 and G= 0.64. We observed a higher TT genotype frequency in the male MS group than control subjects (p=0.02), independent of other variables. We found an association between hypertension and TT genotype in females. Our data suggests that 894G>T plays a significant role in the mechanistic interaction between metabolic risk such as hypertension and MS, although sex-related differences may exist.