Polymorphisms of rs1799983 (G>T) and rs1800780 (A>G) of the eNOS gene associated with susceptibility to essential hypertension in the Chinese Hui ethnic population

Combined effects of cigarette smoking, alcohol drinking and eNOS Glu298Asp polymorphism on blood pressure in Chinese male hypertensive subjects

INTRODUCTION

Genetic factors and lifestyle exposures, as well as their combinations, play important roles in the development of hypertension. We examined whether cigarette smoking, alcohol drinking and the Glu298Asp polymorphism of the endothelial nitric oxide synthase (eNOS) gene generate combined effects on blood pressure (BP) in hypertensive subjects.

METHODS

A total of 342 essential hypertensive subjects were recruited from Susong community in Anhui province, China, from July 2017 to January 2018, and the plasma biochemical parameters and the genotype on Glu298Asp polymorphism were determined.

RESULTS

There were no gender differences in the distributions of alleles and genotypes in hypertensive subjects. The proportions of cigarette smoking and alcohol drinking in male hypertensive subjects were remarkably higher than those in the females (p<0.001). The systolic blood pressure (SBP) and diastolic blood pressure (DBP) levels of mutant genotypes (Glu/Asp and Asp/Asp) were significantly higher than those of wild genotype (Glu/Glu) (p=0.013 and 0.026, respectively) in male hypertensive subjects. Moreover, the SBP and DBP levels of the mutant genotype were remarkably higher than those of wild genotype in both cigarette smoking and alcohol drinking male hypertensive subjects (p=0.034 and 0.043, respectively).

CONCLUSIONS

Cigarette smoking, alcohol drinking and the Glu298Asp polymorphism of the eNOS gene generate combined effects that increase the susceptibility of the mutant genotype to BP in Chinese male hypertensive subjects.

Association of polymorphisms in serotonin and nitric oxide genes with clinical outcome of dengue in Brazilian northeast population

Serotonin and nitric oxide seem to be involved in Dengue virus infection. The aim of this study was to investigate if SNPs in serotonin and nitric oxide are associated with dengue severity. A retrospective case-control study was conducted, with groups of dengue fever (DF; n = 78) and dengue hemorrhagic fever patients (DHF; n = 49). Genotyping was performed using qPCR and PCR. The power of the sample size was calculated by G*power software. The heterozygous SL for 5-HTTLPR SNP was significantly correlated with protection against progression to DHF in the codominant SS/SL/LL (OR = 0.22, 95% CI = 0.06-0.81, p = 0.011) and overdominant models SL vs SS + LL (OR = 0.19, 95% CI = 0.06-0.65, p = 0.003). For the ENOS (rs1799983) SNP, the genotype GT was positively associated with protection for development of the clinical form in DHF compared to dengue fever (OR = 0.39, 95% CI = (0.13-1.14), p = 0.0058) in codominant GG/GT/TT and overdominant model GT vs GG + TT (OR = 0.35, 95% CI = (0.12-1.02), p = 0.04). To our knowledge, this is the first study to identify the association of the serotonin and nitric oxide SNPs with dengue severity.

Endothelial nitric oxide synthase: From biochemistry and gene structure to clinical implications of NOS3 polymorphisms

Nitric oxide (NO) is an important vasodilator with a well-established role in cardiovascular homeostasis. While mediator is synthesized from L-arginine by neuronal, endothelial, and inducible nitric oxide synthases (NOS1,NOS3 and NOS2 respectively), NOS3 is the most important isoform for NO formation in the cardiovascular system. NOS3 is a dimeric enzyme whose expression and activity are regulated at transcriptional, posttranscriptional,and posttranslational levels. The NOS3 gene, which encodes NOS3, exhibits a number of polymorphic sites including single nucleotide polymorphisms (SNPs), variable number of tandem repeats (VNTRs), microsatellites, and insertions/deletions. Some NOS3 polymorphisms show functional effects on NOS3 expression or activity, thereby affecting NO formation. Interestingly, many studies have evaluated the effects of functional NOS3 polymorphisms on disease susceptibility and drug responses. Moreover, some studies have investigated how NOS3 haplotypes may impact endogenous NO formation and disease susceptibility. In this article,we carried out a comprehensive review to provide a basic understanding of biochemical mechanisms involved in NOS3 regulation and how genetic variations in NOS3 may translate into relevant clinical and pharmacogenetic implications.

eNOS polymorphisms as predictors of efficacy of bevacizumab-based chemotherapy in metastatic colorectal cancer: data from a randomized clinical trial

BACKGROUND

Bevacizumab plus chemotherapy is a widely used therapeutic option for first-line treatment of metastatic colorectal cancer (mCRC). However, molecular predictors of bevacizumab efficacy have not yet been identified. We analyzed vascular endothelial growth factor (VEGF) and endothelial nitric oxide synthase (eNOS) polymorphisms in relation to response to bevacizumab.

METHODS

Two hundred and thirty-seven patients with mCRC enrolled onto the phase III prospective multicentre randomized "Italian Trial in Advanced Colorectal Cancer (ITACa)" trial were evaluated. One hundred fourteen patients received chemotherapy plus bevacizumab (CT + B) and 123 received chemotherapy (CT) alone. Five single nucleotide polymorphisms (SNPs) (-2578, -1498, -1154, -634 and +936) for VEGF and 2 SNPs (-786, +894) and one variable number tandem repeat in intron 4 for eNOS were analyzed for each patient. The polymorphisms were assessed in relation to progression-free survival (PFS), objective response rate (ORR) and overall survival (OS).

RESULTS

VEGF 936C/T, eNOS +894 G/T and VNTR were significantly correlated with outcome in CT + B patients, but not in CT-only patients. In particular, patients with a specific haplotype combination of the 2 eNOS polymorphisms (defined eNOS Haplo1/Haplo1 and eNOS Haplo 2/Haplo2) showed significantly longer PFS (15.0 vs 9.1 months, P = 0.001) and OS (34.5 vs 20.5 months P = 0.002), and a higher ORR (71 vs 45.9%, P = 0.013) than those with the other genotypes, respectively.

CONCLUSIONS

Specific eNOS polymorphisms may be capable of identifying a subset of mCRC patients who are more responsive to bevacizumab-based chemotherapy. If confirmed, these results would permit individually tailored treatment with bevacizumab.