Endothelial nitric oxide synthase Glu298Asp (G894T) gene polymorphism in coronary artery disease patients with type 2 diabetes mellitus

Noncoding RNAs: Versatile regulators of endothelial dysfunction

Noncoding RNAs have recently emerged as versatile regulators of endothelial dysfunction in atherosclerosis, a chronic inflammatory disease characterized by the formation of plaques within the arterial walls. Through their ability to modulate gene expression, noncoding RNAs, including microRNAs, long noncoding RNAs, and circular RNAs, play crucial roles in various cellular processes involved in endothelial dysfunction (ECD), such as inflammation, pyroptosis, migration, proliferation, apoptosis, oxidative stress, and angiogenesis. This review provides an overview of the current understanding of the regulatory roles of noncoding RNAs in endothelial dysfunction during atherosclerosis. It highlights the specific noncoding RNAs that have been implicated in the pathogenesis of ECD, their target genes, and the mechanisms by which they contribute to ECD. Furthermore, we have reviewed the current therapeutics in atherosclerosis and explore their interaction with noncoding RNAs. Understanding the intricate regulatory network of noncoding RNAs in ECD may open up new opportunities for the development of novel therapeutic strategies to combat ECD.

Coronary Heart Disease in Type 2 Diabetes Mellitus: Genetic Factors and Their Mechanisms, Gene-Gene, and Gene-Environment Interactions in the Asian Populations

Asians are more susceptible to type 2 diabetes mellitus (T2D) and its coronary heart disease (CHD) complications than the Western populations, possibly due to genetic factors, higher degrees of obesity, insulin resistance, and endothelial dysfunction that could occur even in healthy individuals. The genetic factors and their mechanisms, along with gene-gene and gene-environment interactions associated with CHD in T2D Asians, are yet to be explored. Therefore, the objectives of this paper were to review the current evidence of genetic factors for CHD, summarize the proposed mechanisms of these genes and how they may associate with CHD risk, and review the gene-gene and gene-environment interactions in T2D Asians with CHD. The genetic factors can be grouped according to their involvement in the energy and lipoprotein metabolism, vascular and endothelial pathology, antioxidation, cell cycle regulation, DNA damage repair, hormonal regulation of glucose metabolism, as well as cytoskeletal function and intracellular transport. Meanwhile, interactions between single nucleotide polymorphisms (SNPs) from different genes, SNPs within a single gene, and genetic interaction with environmental factors including obesity, smoking habit, and hyperlipidemia could modify the gene's effect on the disease risk. Collectively, these factors illustrate the complexities of CHD in T2D, specifically among Asians.

Essential Role of Nonessential Amino Acid Glutamine in Atherosclerotic Cardiovascular Disease

Atherosclerosis is a major disease that seriously harms human health and is known as the "number one killer" in developed countries and the leading cause of death worldwide. Glutamine is the most abundant nonessential amino acid in the human blood that has multifaceted effects on the body. Recent studies showed that glutamine is negatively corrected with the progression of atherosclerotic lesions. In this review, we focused on the relationship of glutamine with macrophage polarization, nitrification stress, oxidative stress injury, myocardial ischemia-reperfusion injury, and therapeutic angiogenesis to review its roles in atherosclerotic cardiovascular disease.

Assessment of the role of plasma nitric oxide levels, T-786C genetic polymorphism, and gene expression levels of endothelial nitric oxide synthase in the development of coronary artery disease

Background:

Reduced bioavailability of nitric oxide (NO) and the T-786C polymorphism of endothelial nitric oxide synthase (eNOS) gene have been reported as risk factors for the development of coronary artery disease (CAD) with conflicting results. We investigated the association of plasma NO levels, T-786C genetic polymorphism, and gene expression levels of eNOS with CAD risk in an Iranian subpopulation.

Materials and Methods:

Studied population included 100 patients with angiographically verified CAD and 100 ethnically matched controls. Analysis of T-786C genetic polymorphism and gene expression levels of eNOS was conducted by polymerase chain reaction (PCR) restriction fragment length polymorphism and real-time reverse transcription-PCR methods, respectively. Plasma levels of NO were measured using Griess method.

Results:

The CC genotype distribution (15% vs. 6%, P = 0.011) and minor C allele frequency (36.5% vs. 21.5%, P = 0.001) of eNOS T-786C polymorphism differed significantly between CAD patients and control. Furthermore, eNOS T-786C polymorphism was more common among smoker than nonsmoker CAD patients (27.7% vs. 7.8%, P = 0.044). The association of the eNOS T-786C polymorphism with the severity of CAD (number of diseased vessel) was significant (P < 0.05). The gene expression levels of eNOS were significantly lower in the heterozygote (0.49 ± 0.1, P = 0.023) and mutant homozygote (0.36 ± 0.09, P = 0.011) genotypes than that of wild-type genotype (P < 0.05). In addition, NO levels were significantly lower in CAD patients compared with control subjects (42.62 ± 12.26 vs. 55.48 ± 16.57, P = 0.002) and showed intergenotypic variation in the CAD patients.

Conclusion:

Our study indicated that reduced NO levels and eNOS T-786C genetic polymorphism are significant risk factors for the development and severity of CAD in the Iranian population.

Association of Nitric Oxide Levels and Endothelial Nitric Oxide Synthase G894T Polymorphism with Coronary Artery Disease in the Iranian Population

Purpose:

The endothelial nitric oxide synthase (eNOS) G894T polymorphism has been reported to cause endothelial dysfunction and may have a role in the development of coronary artery disease (CAD). The aim of the present study was to investigate the association of eNOS G894T genetic polymorphism and plasma levels of nitric oxide (NO) with CAD risk in an Iranian population.

Materials and Methods:

We studied 200 patients with angiographically documented CAD and 100 matched controls. Analysis of G894T genetic polymorphism of eNOS was performed by polymerase chain reaction-restriction fragment length polymorphism method. Plasma levels of NO were determined using Griess method. Biochemical analysis was conducted by routine colorimetric methods.

Results:

Plasma levels of NO were significantly lower in CAD patients than control subjects (41.60±12.70 vs. 55.48±16.57, P=0.001). Also, the mean plasma levels of NO were significantly lower in T allele carriers of eNOS G894T polymorphism than G allele carriers (P<0.001). The genotype distribution and minor T allele frequency of eNOS G894T polymorphism significantly differed between CAD patients and control subjects (P<0.05). However, no significant association was found between the eNOS G894T polymorphism and the severity of CAD (number of diseased vessel) or the lipid profile of CAD patients (P>0.05).

Conclusion:

Reduced plasma level of NO is associated with increased risk of CAD in our population. Moreover, eNOS G894T polymorphism is a significant risk factor for CAD development via reducing the plasma levels of NO. However, eNOS G894T polymorphism is not a contributing factor for the severity of CAD.

Endothelial nitric oxide synthase gene polymorphism is associated with Legg-Calvé-Perthes disease

The aim of this study was to assess the association of 27-bp variable number tandem repeat (VNTR) polymorphism in intron 4 and G894T polymorphism in exon 7 of the endothelial nitric oxide synthase (eNOS) gene with Legg-Calvé-Perthes disease (LCPD), and to provide a scientific basis for further research into the pathogenic mechanism. A total of 80 patients with LCPD and 100 healthy subjects were recruited in this case-control study. The 27-bp VNTR and G894T polymorphisms of the eNOS gene were genotyped using polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism, respectively, followed by agarose gel electrophoresis and DNA sequencing. Allelic and genotypic frequencies were computed in the two groups and subjected to statistical analysis. For the 27-bp VNTR polymorphism, individuals with LCPD showed a higher frequency of the ab genotype [27.5 vs. 14%; odds ratio (OR), 2.33; 95% confidence interval (CI), 1.10-4.92; P=0.024]. For the G894T polymorphism, the LCPD case group showed a higher frequency of the heterozygous genotype GT than the healthy control group (35 vs. 17%; OR, 2.67; 95% CI, 1.33-5.36; P=0.005). The results indicate that these eNOS gene polymorphisms may be a risk factor for LCPD. The 27-bp VNTR polymorphism in intron 4 and G894T polymorphism in exon 7 may be involved in the etiology of LCPD.

Genetic Effects of eNOS Polymorphisms on Biomarkers Related to Cardiovascular Status in a Population Coexposed to Methylmercury and Lead

The aim of the present study was to evaluate possible effects of endothelial nitric oxide synthase (eNOS) polymorphisms on systolic (SBP) and diastolic blood pressure (DBP) and on nitrite levels in plasma (NitP) in a population coexposed to methylhemoglobin (MeHg) and lead (Pb) in the Amazonian region, Brazil. Plasmatic levels of hemoglobin Hg (HgP) and Pb (PbP) were determined by inductively coupled plasma-mass spectrometry, whereas NitP were quantified by chemiluminescence. Genotyping was performed by conventional and restriction fragment length polymorphism-polymerase chain reaction assay. The population age ranged from 18 to 87 years (mean 40 ± 16), and the distribution between the sexes was homogenous (63 men and 50 women). Mean HgP and PbP were 7.1 ± 6.1 and 1.1 ± 1.1 µg L(-1), respectively. PbP was correlated to SBP and DBP, whereas no effects were observed for HgP on blood pressure. Subjects carrying the 4b allele in intron 4 presented greater SBP and DBP compared with those who had the 4a4a genotype. In addition, interactions between alcohol consumption and the -786 T/C polymorphism were observed on NitP, i.e., individuals carrying the polymorphic allele and drinkers had lower NitP. Taken together, our data give new insights concerning the genetic effects of eNOS polymorphisms on biomarkers related to cardiovascular status in populations coexposed to Hg and Pb.

Endothelial nitric oxide synthase Glu298Asp gene polymorphism influences body composition and biochemical parameters but not the nitric oxide response to eccentric resistance exercise in elderly obese women

Both endothelial nitric oxide synthase (eNOS) gene polymorphism and nitric oxide (NO) are involved in important cardiovascular, muscular and inflammatory physiological mechanisms during ageing and response to exercise. The aim of this study was to investigate the NO kinetic response following an acute eccentric resistance exercise (ERE) session and the possible effect of the Glu298Asp eNOS gene polymorphism in elderly obese women. Eighty-seven women (age 69·4 ± 6·1 years, body weight 74·9 ± 12·7 kg, height 151·9 ± 6·0 cm and BMI 32·5 ± 5·7 kg m^-2 ) completed seven sets of ten eccentric repetitions at 110% of the ten repetitions maximum (10RM). NO concentrations remained elevated up to 48 h following the acute ERE session as compared with baseline, for GG and GT/TT groups (P<0·05), with no differences between genotypes. The GG genotype group had higher body weight, prevalence of obesity (BMI classification - 81% versus 56%), BMI and higher relative muscle strength, while they had significantly lower triglycerides, VLDL and urea concentrations as compared with TT/TG group. In conclusion, NO remains elevated for up to 48 h after an acute ERE session, without genotype interaction. The TT/TG genotype had a negative impact on triglycerides, VLDL and urea concentrations. Thus, T carriers should increase their attention to cardiovascular risk factor and metabolic disorders.

Association of endothelial nitric oxide synthase gene polymorphisms with coronary artery disease: an updated meta-analysis and systematic review

Several association studies of endothelial nitric oxide synthase (NOS3) gene polymorphisms with respect to coronary artery disease (CAD) have been published in the past two decades. However, their association with the disease, especially among different ethnic subgroups, still remains controversial. This prompted us to conduct a systematic review and an updated structured meta-analysis, which is the largest so far (89 articles, 132 separate studies, and a sample size of 69,235), examining association of three polymorphic forms of the NOS3 gene (i.e. Glu298Asp, T786-C and 27bp VNTR b/a) with CAD. In a subgroup analysis, we tested their association separately among published studies originating predominantly from European, Middle Eastern, Asian, Asian-Indian and African ancestries. The pooled analysis confirmed the association of all the three selected SNP with CAD in three different genetic models transcending all ancestries worldwide. The Glu298Asp polymorphism showed strongest association (OR range = 1.28–1.52, and P<0.00001 for all comparisons), followed by T786-C (OR range = 1.34–1.42, and P<0.00001 for all comparisons) and 4b/a, (OR range = 1.19–1.41, and P≤0.002 for all comparisons) in our pooled analysis. Subgroup analysis revealed that Glu298Asp (OR range = 1.54–1.87, and P<0.004 for all comparisons) and 4b/a (OR range = 1.71–3.02, and P<0.00001 for all comparisons) have highest degree of association amongst the Middle Easterners. On the other hand, T786-C and its minor allele seem to carry a highest risk for CAD among subjects of Asian ancestry (OR range = 1.61–1.90, and P≤0.01 for all comparisons).

Association of endothelial nitric oxide synthase gene G894T polymorphism and serum nitric oxide levels in patients with preeclampsia and gestational hypertension

OBJECTIVE

Pregnancy-induced hypertension is one of the most important cause of maternal-fetal morbidity and mortality. Pregnancy-related hypertensive disorders are usually associated with diminished nitric oxide (NO) levels. We aimed to evaluate the role of serum NO levels and eNOS gene G894T polymorphism on hypertensive disorders of pregnancy.

METHODS

Eighty patients with gestational hypertension or preeclampsia, and 80 healthy pregnants were enrolled to analyze serum NO levels and G894T polymorphism of the eNOS gene. NO level was analyzed by high-performance liquid chromatography (HPLC) method. The G894T polymorphism of the eNOS gene was determined by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP).

RESULTS

There was no significant difference between groups in terms of G894T/eNOS genotype and allele frequencies (p > 0.05). Serum NO levels were significantly lower in the patients group. In the control group, subjects with thymine-thymine (TT) genotype had significantly lower NO levels when compared to subjects with guanine-guanine (GG) or guanine-thymine (GT) genotype (p < 0.05).

CONCLUSIONS

We failed to demonstrate an association between eNOS gene G894T polymorphism and serum NO levels in patients with pregnancy-induced hypertensive disorders. We established a relation between pregnancy-induced hypertension and low NO levels.