ACE I allele and eNOS G allele crosstalk may have a role in chronic obstructive pulmonary disease

Increased Frequency of Angiotensin-Converting Enzyme D Allele in Asian Patients With Chronic Obstructive Pulmonary Disease: An Updated Meta-Analysis

At present, the angiotensin-converting enzyme (ACE) I/D polymorphism was considered to be associated to the pathogenesis of chronic obstructive pulmonary disease (COPD). However, the association between it and the risk of COPD in different ethnic groups is still unclear. The purpose of this study is to conduct an updated meta-analysis of the association between them; collect literatures published before 10 February 2023 by searching PubMed, Embase, MEDLINE, CBM, CNKI, Wanfang, and VIP Chinese scientific databases; and display the analysis results by drawing forest plots. At the same time, publication bias, sensitivity analysis, and trial sequential analysis (TSA) were performed to evaluate the stability and reliability of the results. In the overall population, the result of the DD versus II model showed the association with the risk of COPD ([OR] = 1.30, 95% CI [1.08, 1.56]), and there were no associations in other genetic models (p > 0.05). In Caucasians, the results of all genetic models showed no associations (p > 0.05). In Asians, the results of D versus I, DD versus II, and DD versus II + ID models showed the associations with the risk of COPD (D vs. I: [OR] = 1.48, 95% CI [1.14, 1.93]; DD vs. II: [OR] = 2.04, 95% CI [1.53, 2.72]; DD vs. II + ID: [OR] = 2.19, 95% CI [1.45, 3.29]), while the results of ID versus II and DD + ID versus II models showed no associations (p > 0.05). Therefore, the D allele and "DD" genotype variation of the ACE I/D gene polymorphism are associated with susceptibility to COPD in Asians but not in Caucasians.

Interactions of the eNOS and ACE genes and cigarette smoking in chronic obstructive pulmonary disease

Background

Chronic obstructive pulmonary disease (COPD) is a complex disorder with unexplained heritability. Interactions of genetic and environmental factors are thought to be crucial in COPD. So, we aim to examine interactions of the endothelial nitric oxide synthase (eNOS) and angiotensin converting enzyme (ACE) genes and cigarette smoking in COPD.

Methods

The eNOS G 894T and ACE ID variants were analyzed in 122 COPD patients and 200 controls from Serbia. The effect of the variants on COPD was assessed by logistic regression. Interactions between eNOS, ACE and cigarette smoking in COPD were evaluated using a case-control model. Interaction between the genes was analyzed in silico.

Results

No effect of the eNOS G 894T and ACE ID variants on COPD was found in our study. Gene-gene interaction between the eN OS T T and A CE D was identified (p=0.033) in COPD. The interaction is realized within the complex network of biochemical pathways. Gene-environment interactions between the eNOS T and cigarette smoking (p=0.013), and the ACE II and cigarette smoking (p=0.009) were detected in COPD in our study.

Conclusions

This is the first research to reveal interactions of the eNOS and ACE genes and cigarette smoking in COPD progressing our understanding of COPD heritability and contributing to the development of appropriate treatments.

Association of angiotensin-converting enzyme gene I/D polymorphism with chronic obstructive pulmonary disease: a meta-analysis

Objectives:

We conducted a meta-analysis of published studies on the angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism associated with the risk of chronic obstructive pulmonary disease, as well as with pulmonary function and circulating angiotensin-converting enzyme changes.

Methods:

A literature search, quality assessment and data extraction were completed independently and in duplicate.

Results:

A total of 16 articles were meta-analysed, including 12 articles (2113 patients and 8786 controls) for chronic obstructive pulmonary disease risk and eight articles (11,664 subjects) for pulmonary and circulating phenotypes. In overall and subgroup analyses, no significance was noted between the I/D polymorphism and chronic obstructive pulmonary disease risk under all genetic models (P>0.05), without heterogeneity or publication bias. Carriers of II, ID and II plus ID genotypes had significantly lower levels of circulating angiotensin-converting enzyme than those with the DD genotype (weighted mean difference −13.35, −8.13 and −10.74 U/L, respectively, P<0.001). For forced expiratory volume in one second (FEV₁)/forced vital capacity, carriers of the DD genotype had marginally lower levels than those with the DD genotype (weighted mean difference –1.66, P=0.034). Furthermore in the case of FEV₁ of 50% or greater of predicted FEV₁, FEV₁ was marginally lower in ID genotype carriers than DD genotype carriers (weighted mean difference −3.50, P=0.056).

Conclusions:

Our meta-analytical findings demonstrated that the ACE gene I/D polymorphism was not associated with the risk of chronic obstructive pulmonary disease.

Analysis of Angiotensin Converting Enzyme, Endothelial Nitric Oxide Synthase & Serotonin Gene Polymorphisms among Atrial Septal Defect Subjects with and without Pulmonary Arterial Hypertension

Genetic polymorphisms are variations in DNA sequences which can influence either disease susceptibility, severity, or prognosis. Pulmonary arterial hypertension (PAH) is one of the complications that occurs in certain patients who have atrial septal defect (ASD). This study seeks to determine the association of gene polymorphisms with the pathogenesis of PAH in ASD patients. This study was conducted on 30 ASD patients with PAH, and 50 ASD patients who were not diagnosed with PAH. All respondents were Malay. Patients were selected based on stringent inclusion and exclusion criteria. Molecular analyses were done to detect the genetic polymorphisms of angiotensin converting enzyme (ACE I/D), serotonin transporter (5-HTTLPR), endothelial nitric oxide synthase (eNOS) G894T, and eNOS 4b/4a. The genotypes of these genetic polymorphisms were determined using conventional PCR and PCR-RFLP methods. The PCR products were analysed using agarose gel electrophoresis. Statistical analysis was done using SPSS Version 22. Clinical characteristics, such as the diameter of ASD, mean arterial pressure (MAP), and mean pulmonary artery pressure (mPAP) differed significantly (p < 0.05). Based on the statistical analysis, ACE I/D, eNOS G894T, and eNOS 4b/4a do not contribute to the progression of PAH amongst ASD patients (p > 0.05). However, the L allele of the 5-HTTLPR gene polymorphism may have an affect on the development of PAH in ASD patients (p < 0.05).

ACE gene polymorphism is associated with COPD and COPD with pulmonary hypertension: a meta-analysis

Purpose

Angiotensin-converting enzyme (ACE) gene I/D polymorphism has been studied in relation to the susceptibility to COPD and COPD with pulmonary hypertension (PH) with inconclusive results. We performed the first comprehensive meta-analysis to evaluate accurately the association between the ACE gene polymorphism and the risk of COPD.

Methods

Data were analyzed using odds ratios (ORs) and the corresponding 95% CIs to measure the strength of the models. Subgroup analyses were conducted by ethnicity and complication which referred to PH.

Results

In total, 15 studies (2,635 participants) were included in our study, of which four studies (288 participants) were for PH subgroup. The overall analysis results indicated that the ACE gene polymorphism was not associated with COPD susceptibility in all gene models. However, the ethnic subgroup analysis results indicated that ACE gene polymorphism was associated with Asians’ susceptibility to COPD (DD+DI vs II, OR=1.47, P=0.019, 95% CI: 1.07–2.02). Further, the overall results of the present study detected no statistical significance between ACE gene polymorphism and the risk of COPD with PH, but the homozygote variant (DD) increased the risk of PH in Asian COPD patients (DD vs ID+II, OR=2.05, P=0.05, 95% CI: 1.00–4.19).

Conclusion

The current study suggests that ACE polymorphism, particularly the homozygote variant (DD), might contribute to the risk of COPD and COPD with PH among Asians. Further studies with larger sample size and more ethnicities are expected to be conducted in the future to validate the results.

The -786 T/C polymorphism of NOS3 gene is a susceptibility marker of COPD among Tunisians that correlates with nitric oxide levels and airflow obstruction

OBJECTIVE

The goal of this study was to examine the role of G894T (rs1799983), -786T/C (rs3918161) and a 27 bp variable number of tandem repeats (VNTR) 4B/4A of NOS3 gene on the risk and severity of COPD.

METHODS

The study included 194 controls and 138 COPD patients. NOS3 G894T, -786T/C and 4B/4A variants were determined by PCR analysis based on the banding pattern on gel electrophoresis. Pulmonary function was evaluated using body plethysmography. The levels of nitric oxide, peroxynitrite and lipid peroxides (T-BARS) were determined using spectrophotometric methods. Levels of serum IL-6, TNF-α and TGFβ were determined by ELISA.

RESULTS

In case-control studies, both G894T and -786T/C variants were associated with COPD risk. A significantly increased risk of COPD was found with the NOS3894T and -786C alleles (OR:1.93, P=0.001; OR:2.05, P=0.001, respectively). No significant impact of the G894T and 4B/4A SNPs was found on COPD severity, while a significant correlation was retrieved between the NOS3 -786T/C variation and advanced stages (OR: 1.89, P=0.009). In addition, COPD patients with the -786CC genotype exhibited lower FEV1% values in comparison to -786TT carriers (48±3.28 vs. 58.06±2.3, P=0.01, respectively). Patients having the -786CC genotype presented lower plasma levels of nitric oxide and higher T-BARS in comparison to -786TT individuals (173.22±13.4 vs. 228.93±16.8, P=0.01; 1.8±0.15 vs. 1.22±0.15, P=0.01, respectively).

CONCLUSION

This study provides the first evidence for the association of G894T, -786T/C variants with COPD risk among Tunisians. The -786T/C variation correlates with enhanced airflow limitation. This finding could be related to altered levels of nitric oxide and enhanced lipid peroxides among patients carrying the -786CC genotype.

Genetic Polymorphism of Angiotensin-Converting Enzyme and Chronic Obstructive Pulmonary Disease Risk: An Updated Meta-Analysis

The relationship between polymorphism of the angiotensin I converting enzyme (ACE) gene and chronic obstructive pulmonary disease (COPD) has been examined in many previous studies. However, their results were controversial. Therefore, we performed a meta-analysis to evaluate the relationship between the ACE gene and the risk of COPD. Fourteen case-control studies were included in this meta-analysis. The pooled p value, odds ratio (OR), and 95% confidence interval (95% CI) were used to investigate the strength of the association. The meta-analysis was performed using comprehensive meta-analysis software. Our meta-analysis results revealed that ACE polymorphisms were not related to the risk of COPD (p > 0.05 in each model). In further analyses based on ethnicity, we observed an association between insertion/deletion polymorphism of the ACE gene and risk of COPD in the Asian population (codominant 2, OR = 3.126, 95% CI = 1.919–5.093, p < 0.001; recessive, OR = 3.326, 95% CI = 2.190–5.050, p < 0.001) but not in the Caucasian population (p > 0.05 in each model). In conclusion, the present meta-analysis indicated that the insertion/deletion polymorphism of the ACE gene may be associated with susceptibility to COPD in the Asian population but not in the Caucasian population. However, the results of the present meta-analysis need to be confirmed in a larger sample.

Expression of Nitric Oxide Synthase Isoenzyme in Lung Tissue of Smokers with and without Chronic Obstructive Pulmonary Disease

Background:

It has been demonstrated that only 10%–20% cigarette smokers finally suffer chronic obstructive pulmonary disease (COPD). The underlying mechanism of development remains uncertain so far. Nitric oxide (NO) has been found to be closely associated with the pathogenesis of COPD, the alteration of NO synthase (NOS) expression need to be revealed. The study aimed to investigate the alterations of NOS isoforms expressions between smokers with and without COPD, which might be helpful for identifying the susceptibility of smokers developing into COPD.

Methods:

Peripheral lung tissues were obtained from 10 nonsmoker control subjects, 15 non-COPD smokers, and 15 smokers with COPD. Neuronal NOS (nNOS), inducible NOS (iNOS), and endothelial NOS (eNOS) mRNA and protein levels were measured in each sample by using real-time polymerase chain reaction and Western blotting.

Results:

INOS mRNA was significantly increased in patients with COPD compared with nonsmokers and smokers with normal lung function (P < 0.001, P = 0.001, respectively). iNOS protein was also higher in COPD patients than nonsmokers and smokers with normal lung function (P < 0.01 and P = 0.01, respectively). However, expressions of nNOS and eNOS did not differ among nonsmokers, smokers with and without COPD. Furthermore, there was a negative correlation between iNOS protein level and lung function parameters forced expiratory volume in 1 s (FEV₁) (% predicted) (r = −0.549, P = 0.001) and FEV₁/forced vital capacity (%, r = −0.535, P = 0.001).

Conclusions:

The expression of iNOS significantly increased in smokers with COPD compared with that in nonsmokers or smokers without COPD. The results suggest that iNOS might be involved in the pathogenesis of COPD, and may be a potential marker to identify the smokers who have more liability to suffer COPD.

Nitric oxide synthase polymorphisms, gene expression and lung function in chronic obstructive pulmonary disease

Background

Due to the pleiotropic effects of nitric oxide (NO) within the lungs, it is likely that NO is a significant factor in the pathogenesis of chronic obstructive pulmonary disease (COPD). The aim of this study was to test for association between single nucleotide polymorphisms (SNPs) in three NO synthase (NOS) genes and lung function, as well as to examine gene expression and protein levels in relation to the genetic variation.

Methods

One SNP in each NOS gene (neuronal NOS (NOS1), inducible NOS (NOS2), and endothelial NOS (NOS3)) was genotyped in the Lung Health Study (LHS) and correlated with lung function. One SNP (rs1800779) was also analyzed for association with COPD and lung function in four COPD case–control populations. Lung tissue expression of NOS3 mRNA and protein was tested in individuals of known genotype for rs1800779. Immunohistochemistry of lung tissue was used to localize NOS3 expression.

Results

For the NOS3 rs1800779 SNP, the baseline forced expiratory volume in one second in the LHS was significantly higher in the combined AG + GG genotypic groups compared with the AA genotypic group. Gene expression and protein levels in lung tissue were significantly lower in subjects with the AG + GG genotypes than in AA subjects. NOS3 protein was expressed in the airway epithelium and subjects with the AA genotype demonstrated higher NOS3 expression compared with AG and GG individuals. However, we were not able to replicate the associations with COPD or lung function in the other COPD study groups.

Conclusions

Variants in the NOS genes were not associated with lung function or COPD status. However, the G allele of rs1800779 resulted in a decrease of NOS3 gene expression and protein levels and this has implications for the numerous disease states that have been associated with this polymorphism.

Angiotensin-converting enzyme I/D polymorphism is associated with COPD risk in Asian population: evidence from a meta-analysis

Several molecular epidemiological studies were conducted in recent years to evaluate the risk of chronic obstructive pulmonary disease (COPD) associated with insertion/deletion (I/D) polymorphism of angiotensin-converting enzyme (ACE). However, the results remain conflicting rather than conclusive. To derive a more precise estimation of association between ACE polymorphism and the risk of COPD, we performed a meta-analysis from all available relevant studies. We used odds ratios (ORs) with 95% confidence intervals (CIs) to assess the strength of the association. There was a markedly positive association between the D allele or DD genotype and COPD risk in Asians (D vs. I: OR = 1.55, 95% CI = 1.407-2.44; DD vs. II: OR = 2.53, 95% CI = 1.65-3.89; DD vs. DI/II: OR = 2.09, 95% CI = 1.09-4.03), but this association was not observed in Europeans (D vs. I: OR = 0.93, 95% CI = 0.75-1.15; DD vs. II: OR = 0.86, 95% CI = 0.56-1.33; DD vs. DI/II: OR = 0.88, 95% CI = 0.63-1.23). Our meta-analysis provides strong evidence that D allele and DD homozygous might be significant genetic molecular markers for COPD susceptibility in Asians, but not for Europeans. Additional well-designed large studies were required for the validation of our results.

Updates on the COPD gene list

A genetic contribution to develop chronic obstructive pulmonary disease (COPD) is well established. However, the specific genes responsible for enhanced risk or host differences in susceptibility to smoke exposure remain poorly understood. The goal of this review is to provide a comprehensive literature overview on the genetics of COPD, highlight the most promising findings during the last few years, and ultimately provide an updated COPD gene list. Candidate gene studies on COPD and related phenotypes indexed in PubMed before January 5, 2012 are tabulated. An exhaustive list of publications for any given gene was looked for. This well-documented COPD candidate-gene list is expected to serve many purposes for future replication studies and meta-analyses as well as for reanalyzing collected genomic data in the field. In addition, this review summarizes recent genetic loci identified by genome-wide association studies on COPD, lung function, and related complications. Assembling resources, integrative genomic approaches, and large sample sizes of well-phenotyped subjects is part of the path forward to elucidate the genetic basis of this debilitating disease.

The D/I polymorphism in the angiotensin-converting enzyme gene and chronic obstructive pulmonary disease risk: a meta-analysis

BACKGROUND

The deletion/insertion (D/I) polymorphism in the angiotensin-converting enzyme (ACE) gene has been implicated in susceptibility of chronic obstruction pulmonary disease (COPD), but a number of studies have reported inconclusive results. The aim of this study is to investigate the relationship between the D/I polymorphism in the ACE gene and COPD risk by meta-analysis.

METHOD

We searched Pubmed database, Embase database, CNKI database and Wanfang database, covering all studies until October 10, 2011. Statistical analysis was performed by using the software Revman4.2 and STATA 10.0.

RESULTS

A total of 710 COPD cases and 862 controls in 10 case-control studies were included in this study. The results suggested that the DD homozygote carriers did not have an increased or decreased risk of COPD when compared with the heterozygote DI and II homozygote carriers. However, in the subgroup analysis by race, significant increased risks were found in Asian DD homozygote carriers (OR = 2.6 and 95% CI = 1.47-4.57 for DD vs. DI+II) but not in Caucasian DD homozygote carriers (OR = 0.91, 95%CI = 0.69-1.22, P = 0.54 for DD vs. DI+II).

CONCLUSIONS

This meta-analysis suggested that the ACE gene is a COPD susceptible gene in Asian populations. Future studies are needed to validate our conclusions..

Genetic influences on right ventricular systolic pressure (RVSP) in chronic obstructive pulmonary disease (COPD)

BACKGROUND

Pulmonary hypertension (PH) is a complication of chronic obstructive pulmonary disease (COPD). This study examined genetic variations in mediators of vascular remodelling and their association with PH in patients with COPD. In patients with COPD, we genotyped 7 SNPs in 6 candidate PH genes (NOS3, ACE, EDN1, PTGIS, SLC6A4, VEGFA). We tested for association with right ventricular systolic pressure (RVSP), spirometry and gas transfer, and hypoxemia.

METHODS

In patients with COPD, we genotyped 7 SNPs in 6 candidate PH genes (NOS3, ACE, EDN1, PTGIS, SLC6A4, VEGFA). We tested for association with right ventricular systolic pressure (RVSP), spirometry and gas transfer, and hypoxemia.

RESULTS

580 COPD patients were recruited, 341 patients had a transthoracic echocardiogram, with RVSP measurable in 278 patients (mean age 69  years, mean FEV1 50% predicted, mean RVSP 44  mmHg, median history of 50 pack-years). Of the 7 tested SNPs, the NOS3-VNTR polymorphism was significantly associated with RVSP in a dose-dependent fashion for the risk allele: mean RVSP for a/a and a/b genotypes were 52.0 and 46.6  mmHg respectively, compared to 43.2  mmHg for b/b genotypes (P = 0.032). No associations were found between RVSP and other polymorphisms. ACE II or ID genotypes were associated with a lower FEV1% predicted than the ACE DD genotype (P = 0.028). The NOS3-298 TT genotype was associated with lower KCO % predicted than the NOS3-298 GG or GT genotype (P = 0.031).

CONCLUSIONS

The NOS3-VNTR polymorphism was associated with RVSP in patients with COPD, supporting its involvement in the pathogenesis of PH in COPD. ACE and NOS3 genotypes were associated with COPD disease severity, but not with the presence of PH. Further study of these genes could lead to the development of prognostic and screening tools for PH in COPD.

Role of angiotensin-converting enzyme gene polymorphism in persistent pulmonary hypertension of the newborn

AIM

To evaluate the association of angiotensin-converting enzyme (ACE) gene polymorphism with risk/severity of persistent pulmonary hypertension of the newborn (PPHN) among at risk infants.

METHODS

Infants ≥ 34 weeks with respiratory distress at birth were recruited. PPHN was diagnosed clinically and by cardiac echocardiogram. Control group consisted of infants with respiratory distress who did not develop PPHN. ACE genotyping (DD, II, DI genotypes) and serum ACE levels were determined.

RESULTS

A total of 120 infants were included (PPHN = 44; control = 76). Frequency of ACE DD genotype was not different between the two groups of infants (25% versus 33%). Among PPHN infants, severity of illness did not differ between genotypes. Mean (SD) serum ACE levels [15 (9) versus 24 (13) versus 29 (14) U/L] were positively associated with the number of D alleles and inversely associated with infants' gestational age (GA) and level of cardiovascular support.

CONCLUSION

Angiotensin-converting enzyme gene polymorphism did not impact the risk or severity of PPHN among infants ≥ 34 weeks GA.

Polymorphisms of renin-angiotensin system genes as a risk factor for high-altitude pulmonary oedema

The genes of the renin—angiotensin system (RAS) play an important role in the regulation of pulmonary vascular tone. Although studies on individual genes polymorphisms have reported association with high-altitude pulmonary oedema (HAPE), studies on multiple genes or epistasis are lacking. We therefore investigated the association of the RAS polymorphisms with HAPE. In a case-control design, we screened 163 HAPE-resistant/controls (HAPE-r) and 160 HAPEpatients (HAPE-p) of Indian origin for eight polymorphisms of four RAS genes, ACE, AGT, AGTR1 and AGTR2. Significant difference in genotype and allele frequencies of the ACE I/D and AGT M235T polymorphisms was observed between HAPE-p and HAPE-r ( p < 0.05). In three-locus haplotype analysis of AGT the haplotype GTM was significantly higher in HAPE-p (29%) and haplotype GTT in HAPE-r (27%) after Bonferroni correction ( p < 0.006). The differences were insignificant for polymorphisms from AGTR1 and AGTR2. The MDR (multifactor dimensional reduction) approach for gene—gene interaction depicted individual polymorphism M235T as the best disease predicting model (cross validation consistency, CVC = 10/10). We found a significant association of D allele of ACE and M allele of AGT with HAPE. The findings are supported at the haplotypic level as well as through nested genetic interaction between the RAS gene polymorphisms using the MDR approach.

CYP1A1, CYP1A2 and CYBA gene polymorphisms associated with oxidative stress in COPD

BACKGROUND

The genetic susceptibility to chronic obstructive pulmonary disease (COPD) depends on detoxification and antioxidant enzymes, which detoxify cigarette smoke reactive components that, otherwise, generate oxidative stress.

METHODS

In a case-control study of 346 subjects with and without COPD, we examined the polymorphisms 462Ile/Val, 3801T/C of CYP1A1, -3860G/A of CYP1A2 and -930A/G, 242C/T of CYBA individually or in combination and their contribution to oxidative stress markers by measuring malondialdehyde (MDA), catalase (CAT), glutathione (GSH) and glutathione peroxidase (GPx).

RESULTS

COPD patients had significantly increased MDA concentration (p<0.001) and decreased CAT activity, GSH concentration, GPx activity (p< or =0.01). The patients were over-represented by the alleles 462Val, 3801C of CYP1A1 and -930G, 242C of CYBA (p<0.001, p=0.003, p=0.030 and p=0.031, respectively) and consequently the haplotypes of same alleles i.e. 462Val:3801C, 462Val:3801T and -930G:242C (p=0.048, p=0.016 and p=0.039, respectively). Similarly, CYP1A1 and CYP1A2 haplotypes, 462Val:3860G and 462Val:3801T:3860G were significantly over-represented (p=0.001 and p=0.003), respectively in patients. The same alleles-associated genotype-combinations between genes were more prevalent in patients. Of note, the genotypes, 462Ile/Val+Val/Val, 3801TC+CC of CYP1A1 and -930AG+GG of CYBA associated with increased MDA concentration (p=0.018, p=0.045 and p=0.017, respectively), decreased CAT activity (p<0.0001, p=0.080 and p<0.0001, respectively) and GSH concentration (p<0.0001, p=0.0002 and p=0.011, respectively) in patients.

CONCLUSION

The identified alleles, its haplotypes and the genotype-combination along with increased oxidative stress, signify the importance in susceptibility to COPD.

COX2 and p53 risk-alleles coexist in COPD

BACKGROUND

Cigarette smoke stimulates airway epithelial cells to release pro-inflammatory cytokines which influence various inflammation-related genes, including COX2, whereas p53 expression is known to alter in such a condition. Since both the genes share several common physiological functions including inflammation and oxidative stress, we investigated within gene and gene-gene interactions towards susceptibility to the disease.

METHOD

In a prospective gene-association study we conducted PCR-RFLP for genotyping the COX2 -765G/C and 8473T/C and p53 72Pro/Arg polymorphisms in 229 COPD patients and 147 healthy controls.

RESULTS

The -765GC+CC genotypes of COX2 and Pro/Pro+Pro/Arg genotypes of p53 were prevalent in patients with significant odds ratio, 2.05 and 2.30, respectively (p=0.001; p=0.009, respectively), as a consequence, the -765C and 72Pro alleles were prevalent (p<or=0.001). Individually, the 8473T/C polymorphism did not associate with the disease (p=NS), however, it did in the haplotype -765C:8473C, which was significantly higher in patients (p<0.0001). Based on its prevalence, the three alleles were identified as risk-alleles in patients. The combinations of the genotypes containing 3, 4 and 5 risk alleles of the 3 polymorphisms were significantly over-represented in patients, whereas, the genotypes combinations containing 0, 1 and 2 risk alleles were significantly higher in controls (p=0.0004). The pairwise gene-gene interactions validated prevalence of risk-alleles associated pairing of genotypes such as the Pro/Pro+ Pro/Arg with -765GC+-765CC in patients (p=0.01).

CONCLUSION

The prevalence of COX2 and p53 risk-alleles contributes towards susceptibility to the disease.

Endothelial nitric oxide synthase gene variants contribute to oxidative stress in COPD

Nitric oxide (NO) plays critical role in endothelial dysfunction and oxidative stress in COPD, pointing to the significance of endothelial nitric oxide synthase gene (eNOS) variants. We investigated the association of -786T/C, -922A/G, 4B/4A, and 894G/T polymorphisms of eNOS with the disease and its impact on nitrite and malonaldehyde levels in 190 COPD patients and 134 healthy controls, all smokers. The -786C, -922G and 4A alleles were significantly over-represented in patients (p=0.02, p=0.02, and p=0.03, respectively). The haplotypes, -786C:4A, 4A:894G, -786C:894G, and -786C:4A:894G were significantly over-represented in patients (p<0.0001, p =0.02, p=0.02, and p <0.0001, respectively), whereas, haplotypes, -786T:4B, 4B:894G, -786T:894G, and -786T:4B:894G were significantly under-represented in the patients (p<0.0001). The patients had significantly increased levels of nitrite (p=0.003) and malonaldehyde (p<0.0001). Combination of genotypes containing -786C and 4A alleles were greater in patients (p 0.05), and these combinations associated with decreased FEV1 value and nitrite level (p=0.03 and p=0.04, respectively) and with increased malonaldehyde levels (p=0.02). The eNOS -786C, -922G, and 4A alleles, these alleles associated haplotypes and genotype combinations were over-represented in patients. The variants and their combinations of four polymorphisms of eNOS contribute to disturbed pulmonary function and oxidative stress in COPD.

Increased incidence of idiopathic persistent pulmonary hypertension in Down syndrome neonates

Down syndrome (DS) patients have an increased risk of developing pulmonary hypertension later in life compared to age-matched controls. The goal of this study was to determine if the incidence of persistent pulmonary hypertension of the newborn (PPHN) is also higher in neonatal DS patients compared to the general population. A retrospective chart review of DS patients admitted during a 3-year period to the neonatal intensive care unit was performed. DS patients with meconium aspiration syndrome, pulmonary infections, or pulmonary space-occupying lesions were excluded. DS patients were divided into four groups based on treatment and consisted of no intervention (A), supplemental oxygen (B,) mechanical ventilation use (C), and inhaled nitric oxide administration (D). Group D was defined as having PPHN. z test of the difference between sample and known population, chi-square, t-test, and analysis of variance with Tukey adjusted post hoc test were used for analysis. p<0.05 was considered significant. A total of 58 patients met inclusion criteria. Twenty-four DS patients were in group A, 17 in group B, 10 in group C, and 7 in group D. There was no difference between the four groups for gender (males: 10, 5, 5, and 5, respectively), gestational age (36.4, 38.2, 36.4, and 36.4 weeks, respectively), weight (2.8, 3.0, 2.4, and 3.0 kg, respectively), or the presence of congenital heart defects (17, 10, 6, and 1, respectively). The estimated number of DS patients born in the state of Ohio during this period was 598; therefore, the incidence of PPHN in DS was 1.2%. The reported incidence of PPHN is 0.1%. The reported incidence of PPHN was significantly lower versus the incidence of PPHN in DS (z=2.7, p=0.007). It was concluded that DS patients have an increased incidence of PPHN compared to historical controls regardless of baseline demographics.

Correlation of oxidative status with BMI and lung function in COPD

OBJECTIVES

The imbalance in oxidative status together with nutrition depletion and low body weight play a vital role in the pathogenesis and severity of chronic obstructive pulmonary disease (COPD). The study was undertaken to ascertain if a relationship existed between oxidative status and BMI in COPD. In addition, association of oxidative status and BMI with lung function of the disease was also examined.

MATERIALS AND METHODS

In 202 COPD patients and 136 healthy controls plasma lipid peroxidation (LPO), reduced glutathione (GSH), glutathione peroxidase (GPx), catalase (CAT) activities, BMI and FEV(1)% predicted were looked for interactions.

RESULTS

The patients had increased LPO (p=0.006) and decreased antioxidants (GSH, p=0.005; GPx, p=0.035 and CAT, p=0.008, respectively). Of note are the correlations of oxidative stress markers with BMI and FEV(1)% predicted in the patients. LPO inversely and GSH, GPx, and CAT positively correlated with both BMI (p=0.007, p<0.001, p=0.045 and p=0.009, respectively), and FEV(1)% of predicted (LPO, p=0.001; GSH, p<0.001; GPx, p=0.043 and CAT, p<0.001) in the patients. Further, a positive correlation existed between BMI and FEV(1)% predicted (p=0.016) in COPD.

CONCLUSION

The intimate relationship of oxidative status with BMI and lung function, and the direct correlation between BMI and FEV(1) may potentiate severity of the disease.

Genetic polymorphisms of GSTP1 and mEPHX correlate with oxidative stress markers and lung function in COPD

The genetic susceptibility to COPD might depend on variations in detoxification enzymes that activate and detoxify cigarette smoke products, which otherwise generate oxidative stress causing pathogenesis. In a case-control study of 202 COPD patients and 136 normals, we examined the association of polymorphisms I105V, A114V of GSTP1 and Y113H, H139R of mEPHX individually or in combination with disease and their contribution to oxidative stress markers such as MDA, GSH, GPx and airflow obstruction. Patients were over-represented by the alleles 105V, 114V of GSTP1 and 113H, 139H of mEPHX (chi(2)=10.63, p=0.001, chi(2)=13.92, p<0.001, chi(2)=13.02, p<0.001 and chi(2)=4.48, p=0.034, respectively) and the haplotypes of same alleles i.e. 105V-114V and 113H-139H (chi(2)=14.58, p<0.001 and chi(2)=23.14, p<0.001). Moreover, there was marked over-representation of combination of genotypes, I105I+A114A of GSTP1 (53% vs. 36%) in controls; whereas, the combinations with 105V/114V alleles (64% vs. 47%) of GSTP1 (OR=1.99; 95% CI=1.28-3.09; p=0.002) and the homozygotes H113H+H139H (27% vs.10%) of mEPHX (OR=3.26; 95% CI=1.73-6.15; p=0.0001) in patients. Patients had significantly elevated MDA level (p<0.001) and decreased GSH level (p<0.001) and GPx activity (p=0.035), respectively. Of note, the genotypes, I105V/V105V, A114V/V114V of GSTP1 and Y113H/H113H of mEPHX associated with increased MDA level (p=0.04, p=0.03 and p=0.003), decreased GSH level (p=0.019, p=0.007 and p=0.0006) and lower FEV1 (p=0.23, p=0.037 and p=0.029), respectively, in patients; so was the correlation of these biomarkers and lung function with the combinations of the genotypes. In conclusion, 105V/114V alleles of GSTP1 and 113H/139H alleles of mEPHX and the combination of genotypes with same alleles associated with imbalanced oxidative stress and lung function in patients, signifying the importance in the disease.