Association of the C242T polymorphism in the NADPH oxidase p22 phox gene with carotid atherosclerosis in Slovenian patients with type 2 diabetes

NADPH oxidase p22phox C242T polymorphism is associated with macroalbuminuria in diabetic patients: A meta-analysis

AIMS

Previous studies suggested an association between C242T polymorphism in NADPH Oxidase p22phox and diabetic nephropathy (DN) risk, but the results were inconsistent. To obtain a more precise estimation, we carried out a meta-analysis to analyze the effect of C242T polymorphism in NADPH Oxidase p22phox on DN risk.

METHODS

We searched PubMed, ISI Web of Science, and China National Knowledge Infrastructure for all eligible case-control studies through May 2016. The odds ratios (ORs), together with the 95% confidence intervals (CIs), were calculated to evaluate the strength of association between C242T SNP in NADPH Oxidase p22phox on DN risk.

RESULTS

Overall, ten eligible studies involving a total of 1894 cases and 1746 controls were included in our meta-analysis. The results showed that there was no statistical evidence of association between NADPH oxidase p22phox C242T polymorphism and DN in all genetic models (T vs. C: OR 1.16, 95% CI 0.85-1.59, p=0.34; TT vs. CC: OR 1.49, 95% CI 0.80-2.76, p=0.21; TT/CT vs. CC: OR 1.18, 95% CI 0.81-1.72, p=0.40; TT vs.

CT/CC

OR 1.31, 95% CI 0.82-2.11, p=0.26). However, significant association was found in diabetic patients with macroalbuminuria.

CONCLUSION

This meta-analysis indicates that NADPH oxidase p22phox C242T polymorphism is associated with macroalbuminuria in diabetic patients. However, this conclusion should be interpreted with caution due to the small sample size. Larger sample-size studies with homogeneous patients and well-matched controls are required.

Association of CYBA G640A variation with coronary artery disease in Indians

INTRODUCTION

Oxidative stress induces atherosclerosis by triggering an inflammatory cascade within the vascular wall.

OBJECTIVE

To investigate the role of pro-oxidant and antioxidant gene variations with CAD in Indian subjects.

MATERIALS & METHODS

It's a case-control study and genotyping for the variants MPO G-463A, CYBA G640A, SOD2 Val16Ala and CAT C-262T were performed by conventional PCR techniques.

RESULTS

Only CYBA G640A variant allele was found to be significantly (p = 0.0075) associated with CAD.

CONCLUSION

Although CYBA G640A variation was found to be significant, a larger study is needed to validate these results and establish its role as a biomarker.

Association of the NAD(P)H oxidase p22 phox gene C242T polymorphism with type 2 diabetes mellitus, diabetic nephropathy, and carotid atherosclerosis with type 2 diabetes mellitus: A meta-analysis

Background

Several epidemiological studies have evaluated the association between the NAD(P)H oxidase p22 phox gene C242T polymorphism and the risk of type 2 diabetes mellitus (T2DM), diabetic nephropathy (DN), and carotid atherosclerosis with T2DM (CA), but the results are inconclusive. This meta-analysis was therefore designed to clarify these controversies.

Methods

Systematic searches were performed using electronic databases such as MEDLINE, PubMed, EMBASE, and China National Knowledge Infrastructure, as well as through manual searching of the references of identified articles. A total of 11 publications were eligible for this meta-analysis after running a search on the NAD(P)H oxidase p22 phox gene C242T polymorphism, including 7 with outcomes for T2DM, 7 with outcomes for DN, and 3 with outcomes for CA. The pooled odds ratio (OR) with a 95% confidence interval (CI) was calculated using a fixed effects model (FEM) or a random effects model (REM). Publication bias was tested by Begg's funnel plot analysis. Sensitivity analysis was also performed.

Results

The results showed a significant association between the NAD(P)H oxidase p22 phox gene C242T polymorphism and T2DM risk in the allelic model (REM: OR = 1.23, 95% CI = 1.06–1.43), additive model (FEM: OR = 1.61, 95% CI = 1.14–2.26), and recessive model (FEM: OR = 1.50, 95% CI = 1.10–2.05). A significant association was also observed for DN in the allelic model (REM: OR = 1.25, 95% CI = 1.06–1.47), additive model (FEM: OR = 1.61, 95% CI = 1.08–2.38), and dominant model (REM: OR = 1.26, 95% CI = 1.03–1.54). However, no association was observed for CA. Similar results were obtained in subgroup analysis based on ethnicity.

Conclusions

Results of this meta-analysis suggest that the NAD(P)H oxidase p22 phox gene 242T allele might be associated with an increased risk of T2DM and DN, but not CA.

•

There are significant association between P22 phox gene C242T polymorphism with T2DM DN risk but no significant association with CA.

NADPH oxidase p22phox C242T polymorphism and ischemic cerebrovascular disease: an updated meta-analysis

Background

A growing number of studies on the associations between nicotinamide adenine dinucleotide phosphate (NADPH) oxidase p22^phox C242T polymorphism and risk of ischemic cerebrovascular disease have recently been published, but the results remain inconsistent.

Material/Methods

We performed an updated meta-analysis to evaluate this association. Eight case-control studies were included, involving 2045 cases and 2102 controls. Heterogeneity was assessed by the Q test and the I² statistic. Begg and Egger’s tests were conducted to evaluate publication bias. Odds ratio (OR) was tested to identify the associations.

Results

Significant associations between p22^phox gene C242T polymorphism and ischemic cerebrovascular disease (ICVD) risk were observed in the allelic genetic model (OR=1.33, 95% confidence interval [CI] 1.00–1.77, p=0.048). No statistical significant association was found in the dominant model (OR=0.74, 95% CI 0.54–1.02, p=0.064) and recessive model (OR=1.40, 95% CI 0.89–2.19, p=0.146). Subgroup analysis showed an association in European populations for recessive model (OR=2.13, 95% CI 1.06–4.26, p=0.034) and no significant evidence of association in Asian populations was found (dominant model: OR=0.64, 95% CI 0.41–1.00, p=0.05; recessive model: OR=0.98, 95% CI 0.53–1.81, p=0.948; allelic model: OR=1.51, 95% CI 0.98–2.32, p=0.061).

Conclusions

p22^phox gene C242T polymorphism was associated with ICVD risk in the allelic genetic model, as well as in European populations for recessive model. No evidence showed association between p22^phox gene C242T polymorphism and ICVD risk in the dominant model and recessive model. Furthermore, no association existed in Asian populations for any of the 3 genetic models and European populations in the dominant model and allelic model.

The oxidative molecular regulation mechanism of NOX in children with phenylketonuria

Phenylketonuria (PKU) is the most frequent inherited disorder of amino acid metabolism. In our previous work, we investigated the role of NADPH oxidase (NOX) in a Pahenu2-BTBR PKU mouse model, and an in vitro cell culture model of PKU. In the current study, we evaluated various oxidative stress parameters, namely total antioxidant capacity (T-AOC), glutathione (GSH) and maleic dialdehyde (MDA) in the plasma of 40 PKU children, for further investigating the oxidative molecular regulation mechanism of NOX in PKU. It was observed that T-AOC and GSH markedly decreased in PKU as compared with the control group (P<0.01), and seemed to correlate negatively with Phe level. However, there was no statistical difference in MDA level among the three groups. And 8-isoprostane in the blood samples of PKU2 groups was slightly higher than control group (P<0.05). Additionally, mRNA levels of subunits of NOX included p47(phox) and p67(phox) significantly increased in PKU group (P<0.01). These results reflected that NOX is the important source of reactive oxygen species and is involved in the oxidative molecular regulation mechanism in PKU, which shows a new perspective toward understanding the biological underpinnings of PKU.

Association of the C242T polymorphism in the NAD(P)H oxidase P22 phox gene with type 2 diabetes mellitus risk: a meta-analysis

OBJECTIVES

A number of epidemiological studies have explored the association between NAD(P)H oxidase P22 phox gene C242T (rs4673) polymorphism and susceptibility to type 2 diabetes mellitus (T2DM), but the results are still debatable. Therefore, we conducted a meta-analysis to assess the potential association between the NAD(P)H oxidase P22 phox gene C242T polymorphism and T2DM risk.

METHODS

Electronic literature searches of the PubMed, Embase, Web of Science, CBMdisc, CNKI and Google Scholar were performed up to June 15, 2013. Additionally, hand searching of the references of identified articles was performed. Data analyses were carried out by Stata 11.0.

RESULTS

Seven studies were included in the final meta-analysis, covering a total of 1661 T2DM cases and 1265 controls. The results showed evidence for significant association between the NAD(P)H oxidase P22 phox gene C242T polymorphism and T2DM risk (for T/T vs. T/C: OR=1.61, 95% CI=1.14-2.26, p=0.007; for T/T vs. T/C+C/C: OR=1.50, 95% CI=1.10-2.05, p=0.009). In the subgroup analysis, there was also evidence for significant association between the NAD(P)H oxidase P22 phox gene C242T polymorphism and T2DM risk, either for Asians (T/T vs. T/C+C/C: OR=1.74, 95% CI=1.15-2.64, p=0.009) or for non-Asians (for T allele vs C allele: OR=1.30, 95% CI=1.04-1.61, p=0.02).

CONCLUSIONS

The present meta-analysis indicates that the NAD(P)H oxidase P22 phox gene 242 T allele might be associated with an increased T2DM risk.

The -930A>G polymorphism of the CYBA gene is associated with premature coronary artery disease. A case-control study and gene-risk factors interactions

Reactive oxygen species (ROS) are involved in the pathogenesis of atherosclerosis and coronary artery disease (CAD). NADPH oxidases are the main source of ROS in the vasculature. p22phox is a critical component of vascular NADPH oxidases and is encoded by the CYBA (cytochrome b₂₄₅ alpha) gene. The −930A>G CYBA polymorphism (rs9932581:A>G) modulates the activity of the CYBA promoter, and influences CYBA transcriptional activity. The aim of the present study was to analyze a possible association between the −930A>G polymorphism and CAD and to search for gene–traditional risk factors interactions. 480 subjects were studied: 240 patients with premature CAD, 240 age and sex matched blood donors. The −930A>G polymorphism was genotyped using the TaqMan^® Pre-designed SNP Genotyping Assay (Applied Biosystems). The −930G allele carrier state was a risk factor for CAD (OR 2.03, 95 % CI 1.21–3.44, P = 0.007). A synergistic effect of the −930G allele with overweight/obesity (BMI ≥ 25) and cigarette smoking was found. The estimated CAD risk for BMI ≥ 25 and the −930G allele interaction was about 160 % greater than that predicted by assuming additivity of the effects, and about 40 % greater for interaction of cigarette smoking and the −930G allele. Overweight/obesity was a risk factor for CAD only in the −930G allele carriers (P < 10⁻¹⁰) but not in the AA homozygotes (P = 1.00). In conclusion the −930A>G CYBA polymorphism is associated with CAD in the Polish population. The −930G allele carriers are particularly at risk of consequences of obesity and tobacco smoke exposure.

Association of the -262C/T polymorphism in the catalase gene promoter and the C242T polymorphism of the NADPH oxidase P22phox gene with essential arterial hypertension in patients with diabetes mellitus type 2

AIM

The aim of the present study was to test the association between genetic polymorphisms with functional effects on redox regulation: the -262C/T of the catalase gene promoter (rs1001179), the C242T of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase P22phox gene (rs4673), and the 594C/T polymorphism of the glutathione peroxidase gene (rs1050450) and arterial hypertension (AH) in patients with type 2 diabetes.

METHODS

810 Slovenian subjects (Caucasians) with type 2 diabetes were enrolled in the cross-sectional study. Genotypes were determined by real-time PCR.

RESULTS

Univariate analysis failed to demonstrate an association between either the -262C/T of the catalase gene promoter (rs1001179) or the C242T polymorphism of the P22phox gene (rs4673) or the 594C/T polymorphism of the glutathione peroxidase gene (rs1050450) and AH. After adjustment for age, body mass index, fibrinogen level and high sensitivity C-reactive protein level, rs4673 was found to be an independent risk factor for AH in subjects with type 2 diabetes, whereas rs1001179 and rs1050450 were not.

CONCLUSION

According to the results of cross-sectional study, the tested polymorphism of the NADPH oxidase P22phox gene (rs4673) was found to be associated with the development of AH, indicating that the oxidative stress gene NADPH oxidase might be implicated in the pathogenesis of AH in subjects with type 2 diabetes.

Role of oxidative stress in infectious diseases. A review

Oxidative stress plays a dual role in infections. Free radicals protect against invading microorganisms, and they can also cause tissue damage during the resulting inflammation. In the process of infection, there is generation of reactive species by myeloperoxidase, NADPH oxidase, and nitric oxide synthase. On the other hand, reactive species can be generated among others, by cytochrome P450, some metals, and xanthine oxidase. Some pathologies arising during infection can be attributed to oxidative stress and generation of reactive species in infection can even have fatal consequences. This article reviews the basic pathways in which reactive species can accumulate during infectious diseases and discusses the related health consequences.