Impact of interaction of cigarette smoking with angiotensin-converting enzyme polymorphisms on end-stage renal disease risk in a Han Chinese population

The Effect of PPARγ rs1801282 Variant on Mortality Risk Among Asians With Chronic Kidney Disease: A Cohort Study and Meta-Analysis

Background: Chronic kidney disease (CKD) is a public health issue, and an independent risk factor for cardiovascular disease. The peroxisome proliferator-activated receptor gamma (PPARG) plays an important role in the cardiovascular system. Previous studies have examined one important exon polymorphism, Pro12Ala, in PPARG with respect to mortality of CKD patients, but the results were inconsistent and current evidence is insufficient to support a strong conclusion. This study aimed to examine the correlation between Pro12Ala gene polymorphism and mortality among Asians with CKD by trial sequential analysis (TSA).

Methods: The research was divided into observational research and meta-analysis. For the cohort study, 767 subjects from dialysis centers in Taipei were selected as samples, and tracked from December 2015 to February 2017. For the meta-analysis, relevant literature from “PubMed” and “Embase” databases (until December 2016), was searched and TSA was used to verify the results. In order to achieve the best evidence hierarchies, our retrospective cohort study was added to the meta-analysis and the TSA.

Results: The combined sample size for Asian was 1,685 after adding our cohort study, and there was no significant correlation between PPARG Pro12Ala and mortality by the allele model (RR: 0.85, 95% CI: 0.39–1.83, I² = 79.3%). Under the parameter setting with the RR value of 1.5, TSA estimation presented that the cumulative sample size entered into the futility area, and it confirmed the conclusion in this study.

Conclusion: We found that PPARG Pro12Ala gene polymorphism was not related to mortality in CKD Asians patients, and validated our conclusion using TSA after adding our sample.

Role and interaction between ACE1, ACE2 and their related genes in cardiovascular disorders

Cardiovascular disease is the greatest health care burden and one of the most common causes of death worldwide. Less is known about the genetic factors that are responsible for predisposition to cardiovascular disease thus; the molecular and genetic mechanisms underlying cardiovascular diseases remain obscure. One important regulator of blood pressure homeostasis is the renin-angiotensin system (RAS). The protease renin cleaves angiotensinogen into the inactive decameric peptide angiotensin I (AngI). Angiotensin-converting enzyme (ACE) catalyzes the cleavage of the Ang I into the active octomer angiotensin II (Ang II). In humans, can ACE polymorphism has been associated with determinants of renal and cardiovascular function and pharmacological inhibition of ACE and Ang II receptors are effective in lowering blood pressure and preventing kidney disease. In addition, inhibition of ACE and Ang II receptors has beneficial effects in heart failure. A homologue of ACE, termed ACE2, has been identified; it is predominantly expressed in the vascular endothelial cells of the kidney and heart. Unlike ACE, ACE2 functions as a carboxypeptidase, cleaving a single residue from AngI, generating Ang1-9, and a single residue from AngII to generate Ang1-7. Nevertheless, the in vivo role of ACE2 in the cardiovascular system and the RAS is not known.

PPARG Pro12Ala Polymorphism with CKD in Asians: A Meta-Analysis Combined with a Case-Control Study-A Key for Reaching Null Association

BACKGROUND

So far, numerous meta-analyses have been published regarding the correlation between peroxisome proliferator-activated receptor gamma (PPARG) proline 12 alanine (Pro12Ala) gene polymorphism and chronic kidney disease (CKD); however, the results appear to be contradictory. Hence, this study is formulated with the objective of using existing meta-analysis data together with our research population to study the correlation between PPARG Pro12Ala gene polymorphism and CKD and evaluate whether an accurate result can be obtained.

METHODS

First, literature related to CKD and PPARG Pro12Ala available on the PubMed and EMBASE databases up to December 2016 was gathered from 20 publications. Then, the gathered results were combined with our case-control study of 1693 enrolled subjects and a trial sequential analysis (TSA) was performed to verify existing evidence and determine whether a firm conclusion can be drawn.

RESULTS

The TSA results showed that the cumulative sample size for the Asian sample was 6078 and was sufficient to support a definite result. The results of this study confirmed that there is no obvious correlation between PPARG Pro12Ala and CKD for Asians (OR = 0.82 (95% CI = 0.66-1.02), I² = 63.1%), but this was not confirmed for Caucasians. Furthermore, the case-control sample in our study was shown to be the key for reaching this conclusion.

CONCLUSIONS

The meta-analysis results of this study suggest no significant correlation between PPARG Pro12Ala gene polymorphism and CKD for Asians after adding our samples, but not for Caucasian.

Renin-angiotensin system gene variants and risk of early- and late-onset preeclampsia: A single center case-control study

BACKGROUND

Changes in the renin-angiotensin-aldosterone system's (RAAS) activity due to different genetic variations could represent risk factors for the onset of preeclampsia.

OBJECTIVE

To test and quantify the relationships of 8 RAAS gene polymorphisms (angiotensinogen (AGT)-M235T, AGT-T174M, angiotensin converting enzyme (ACE)-I/D, ACE8-A2350G, angiotensin II type 1 receptor (AGTR1)-A1166C, angiotensin II type 2 receptor (AGTR2)-C3123A, renin (REN)-G83A, aldosterone synthase (CYP11B2)-T344C) with susceptibility to early- (EOPE) and late-onset preeclampsia (LOPE).

STUDY DESIGN

We performed polymerase chain reaction- restriction fragment length polymorphism (PCR-RFLP) analysis in 217 pregnant women, of whom 87 pregnant women with EOPE/LOPE and 130 normal pregnant women. The relationship between the studied RASS gene polymorphisms and EOPE/LOPE was tested by multiple logistic regressions.

RESULTS

The multivariate logistic regression analysis showed that AGT-M235T (adjusted OR = 4.63), AGT-T174M (adjusted OR = 4.13), REN-G83A (adjusted OR = 3) and CYP11B2-C344T (adjusted OR = 3.13) gene polymorphisms remained independent risk factors for EOPE. Moreover, ACE-I/D (adjusted OR = 4.04), ACE-A2350G (adjusted OR = 3.5), AGTR1-A1166C (adjusted OR = 2.73), and REN-G83A (adjusted OR = 2.67) polymorphisms remained independent risk factors for LOPE. The frequency of overweight was significantly different (p = 0.001) in pregnant women with EOPE, LOPE and the control group (LOPE:16, 29.6% vs. EOPE:12, 36.4% vs. control group:16, 12.3%). Pregnant women with EOPE had babies with a significantly lower mean birth weight (2067.9 ± 887.9) in comparison to women with LOPE (mean ± SD: 2860.1 ± 771.1, p < 0.001) and women with normal pregnancies, respectively (mean ± SD: 3324.9 ± 484.9, p < 0.001).

CONCLUSION

We confirmed the influence of the renin-angiotensin-aldosterone system through these 8 genetic variations on the onset of preeclampsia.

Investigation of the variants at the binding site of inflammatory transcription factor NF-κB in patients with end-stage renal disease

Background

A chronic inflammatory state is a prominent feature in patients with end-stage renal disease (ESRD). Nuclear factor-kappa B (NF-κB) is a transcription factor that regulates the expression of genes involved in inflammation. Some genetic studies have demonstrated that the NF-κB genetic mutation could cause kidney injury and kidney disease progression. However, the association of a gene polymorphism in the transcription factor binding site of NF-κB with kidney disease is not clear.

Methods

We used the Taiwan Biobank database, the University of California, Santa Cruz, reference genome, and a chromatin immunoprecipitation sequencing database to find single nucleotide polymorphisms (SNPs) at potential binding sites of NF-κB. In addition, we performed a case–control study and genotyped 847 patients with ESRD and 846 healthy controls at Tri-Service General Hospital from 2015 to 2016. Furthermore, we used the ChIP assay to identify the binding activity of different genotypes and used Luciferase reporter assay to examine the function of the rs9395890 polymorphism.

Result

The results of biometric screening in the databases revealed 15 SNPs with the potential binding site of NF-κB. Genotype distributions of rs9395890 were significantly different in ESRD cases and healthy controls (P = 0.049). The ChIP assay revealed an approximately 1.49-fold enrichment of NF-κB of the variant type TT when compared to that of the wild-type GG in rs9395890 (P = 0.027; TT = 3.20 ± 0.16, GT = 2.81 ± 0.20, GG = 1.71 ± 0.18). The luciferase reporter assay showed that the NF-κB binding site activity in T allele was slightly higher than that in G allele, though it is not significant.

Conclusions

Our findings indicate that rs9395890 is associated with susceptibility to ESRD in Taiwan population.

Electronic supplementary material

The online version of this article (10.1186/s12882-019-1471-2) contains supplementary material, which is available to authorized users.

Association of ACE2 polymorphisms with susceptibility to essential hypertension and dyslipidemia in Xinjiang, China

Background

Cardiovascular benefits by reversing environmental risks factors for essential hypertension (EH) and dyslipidemia could be weaken by high genetic risk. We investigated possible associations between ACE2 polymorphisms and dyslipidemia in patients with EH.

Methods

Four hundred and two hypertensive patients were enrolled in an EH group and 233 normotensive individuals were enrolled as control group from the Xinjiang region of China. Fourteen ACE2 polymorphisms were genotyped by Matrix-assisted laser desorption ionization time-of-flight mass spectrometry.

Results

Participants carrying T allele (TT + CT) of rs2074192 (P = 0.006), rs4646155 (P = 0.030) and rs4646188 (P < 0.001), C allele (CT + CT or CC + CG) of rs4240157 (P = 0.012), rs4830542 (P = 0.020) and rs879922 (P < 0.001) and TT genotype of rs2106809 (P = 0.012) were associated with EH. Meanwhile,ACE2 SNPs also exhibited association with dyslipidemia but exhibited obvious heterogeneity. rs1978124 (TT + CT, P = 0.009), rs2106809 (TT, P = 0.045), rs233575 (CC + CT, P = 0.018), rs4646188 (CC, P = 0.011) and rs879922 (CC + CG, P = 0.003) were association with increased LDL-C (≥1.8 mmol/L). rs2106809 (CC + CT, P < 0.001), rs2285666(TT + CT, P = 0.017), rs4646142(CC + CG, P = 0.044), rs4646155(TT + CT, P < 0.001) and rs4646188(TT + CT, P = 0.033) were association with decreased HDL-C (< 1.0 mmol/L). rs2074192 (TT + CT, P = 0.012), rs4240157 (CC + CT, P = 0.027), rs4646156 (AA+AT, P = 0.007), rs4646188 (TT + CT, P = 0.005), rs4830542 (CC + CT, P = 0.047) and rs879922 (CC + CG, P = 0.001) were association with increased TC (≥5.2 mmol/L). rs2106809 (P = 0.034) and rs4646188 (P = 0.013) were associated with hypertriglyceridemia. Further, ischemic stroke was more prevalent with rs4240157 (CC + CT, P = 0.043), rs4646188 (CC + CT, P = 0.013) and rs4830542 (CC + CT, P = 0.037). In addition, rs2048683 and rs6632677 were not association with EH, dyslipidemia and ischemic stroke.

Conclusion

The ACE2 rs4646188 variant may be a potential and optimal genetic susceptibility marker for EH, dyslipidemia and its related ischemic stroke.

Electronic supplementary material

The online version of this article (10.1186/s12944-018-0890-6) contains supplementary material, which is available to authorized users.

The Gene Variants of Maternal/Fetal Renin-Angiotensin System in Preeclampsia: A Hybrid Case-Parent/Mother-Control Study

Preeclampsia (PE) is a common pregnancy-related complication, and polymorphisms in angiotensinogen (AGT), angiotensin-converting enzyme (ACE), and angiotensin II type 1 receptor (AT1R) are believed to contribute to PE development. We implemented a hybrid study to investigate the influence of maternal and fetal ACE I/D, ACE G2350A, AGT M235T, AGT T174M, and AT1R A1166C polymorphisms on PE in Han Chinese women. Polymorphisms were genotyped in 1,488 subjects (256 patients experiencing PE, along with their fetuses and partners, and 360 normotensive controls with their fetuses). Transmission disequilibrium tests revealed that ACE I/D (P = 0.041), ACE G2350A (P = 0.035), and AT1R A1166C (P = 0.018) were associated with maternal PE. The log-linear analyses revealed that mothers whose offspring carried the MM genotype of AGT M235T had a higher risk of PE (OR = 1.54, P = 0.010), whereas mothers whose offspring carried the II genotype of ACE I/D or the GG genotype of ACE G2350A had a reduced risk (OR = 0.58, P = 0.039; OR = 0.47, P = 0.045, respectively). Our findings demonstrate that fetal ACE I/D, ACE G2350A, AGT M235T, and AT1R A1166C polymorphisms may play significant roles in PE development among pregnant Han Chinese women.

Smoking has no impact on survival and it is not associated with ACE gene I/D polymorphism in hemodialysis patients

INTRODUCTION

The relationship between smoking and mortality in patients on hemodialysis is controversial. Earlier studies showed that the insertion/deletion (I/D) polymorphism of the ACE gene might have an effect on mortality. The aim of this study was to test the impact of smoking on survival and whether this association was influenced by ACE gene I/D polymorphism in patients on maintenance hemodialysis.

PARTICIPANTS AND METHODS

In this prospective, multicenter cohort study we analyzed 709 prevalent patients on maintenance hemodialysis. Patients were allocated into groups based on their smoking habit. Outcome data were collected during the 144-month follow-up period. Outcomes of current smokers and lifelong non-smokers were compared. In order to control for interactions between predictor variables, we also identified 160 matched pairs for further sub-analysis.

RESULTS

The vast majority of patients (67%) were non-smokers, followed by current smokers (22.2%) and ex-smokers (9.8%). Smoking had no impact on survival in the matched pair analysis ( p = 0.99). After adjustment for ACE I/D polymorphism and other co-variates, smoking had no effect on survival.

CONCLUSION

Our data suggest that smoking has no impact on survival; neither is it associated with ACE gene I/D polymorphism in hemodialysis patients.

Association of the polymorphism 12109g>A from the REN gene as a risk factor for preterm birth

INTRODUCTION

Preterm birth is the most important cause of neonatal mortality and morbidity. It is a multifactorial disease with different etiologies, including genetic factors. Genetic variability is represented by single nucleotide polymorphisms (SNPs) in genes of proteins involved in the contractile activity. We determine the association between SNP 12109G> A in REN associated with preterm birth and premature rupture of membrane.

MATERIALS AND METHODS

A study of cases ( N=112, 22-36 weeks of gestation; mean: 31, 95% confidence interval 30.7-32.2) and controls ( N=66; 38-40 weeks of gestation from the last menstrual period; mean: 39.8, 95% confidence interval 38.9-39.4) was performed. Genomic DNA was isolated in all patients from peripheral blood. The SNP 12109G> A ( Mbo I) in REN was typified by PCR-restriction fragment length polymorphism.

RESULTS

A significant difference in the case group for the SNP 12109G>A was observed. The A allele was increased in women with preterm birth (81% cases vs. 15% control, p<0.0000004). There was also a significant difference between genotypes, mainly an excess of G/A heterozygotes in women with preterm birth (60% cases vs. 23% controls). The phenotype 12109G> A has odds ratio 6.62 (95% confidence interval 3.14-14.15), which means a high risk of preterm birth/premature rupture of membrane in presence of allele A, both in homozygotes and in heterozygotes.

CONCLUSION

Allelic frequency of A of SNP 12109G>A was higher in women with preterm birth than in women with normal vaginal delivery and could be considered a risk factor.

Angiotensin-Converting Enzyme Insertion/Deletion Polymorphism and Susceptibility to Osteoarthritis of the Knee: A Case-Control Study and Meta-Analysis

Background

Studies of angiotensin-converting enzyme insertion/deletion (ACE I/D) polymorphisms and the risks of knee osteoarthritis (OA) have yielded conflicting results.

Objective

To determine the association between ACE I/D and knee OA, we conducted a combined case-control study and meta-analysis.

Methods

For the case-control study, 447 knee OA cases and 423 healthy controls were recruited between March 2010 and July 2011. Knee OA cases were defined using the Kellgren-Lawrence grading system, and the ACE I/D genotype was determined using a standard polymerase chain reaction. The association between ACE I/D and knee OA was detected using allele, genotype, dominant, and recessive models. For the meta-analysis, PubMed and Embase databases were systematically searched for prospective observational studies published up until August 2015. Studies of ACE I/D and knee OA with sufficient data were selected. Pooled results were expressed as odds ratios (ORs) with corresponding 95% confidence intervals (CI) for the D versus I allele with regard to knee OA risk.

Results

We found no significant association between the D allele and knee OA [OR: 1.09 (95% CI: 0.76–1.89)] in the present case-control study, and the results of other genetic models were also nonsignificant. Five current studies were included, and there were a total of six study populations after including our case-control study (1165 cases and 1029 controls). In the meta-analysis, the allele model also yielded nonsignificant results [OR: 1.37 (95% CI: 0.95–1.99)] and a high heterogeneity (I²: 87.2%).

Conclusions

The association between ACE I/D and knee OA tended to yield negative results. High heterogeneity suggests a complex, multifactorial mechanism, and an epistasis analysis of ACE I/D and knee OA should therefore be conducted.

Gene-gene interactions in renin-angiotensin-aldosterone system contributes to end-stage renal disease susceptibility in a Han Chinese population

Objective. In this study, we investigated whether RAAS gene single nucleotide polymorphisms (SNPs) and their interactions were associated with end-stage renal stage (ESRD). Methodology and Results. This was a case-control study for 647 ESRD cases and 644 controls. AGT (M235T (rs699) and T174M (rs4762)), AGTR1 (A1166C (rs5186) and C573T (rs5182)), ACE (I/D (rs1799752) and G2350A (rs4343)), and CYP11B2 C-344T (rs1799998) were genotyped and compared between cases and controls to identify SNPs associated with ESRD susceptibility. Multifactor dimensionality reduction (MDR) was used to identify gene-gene interactions. Several RAAS genes were associated with ESRD: AGT M235T, ACE I/D, ACE G2350A, and CYP11B2 C-344T. By MDR analysis, a three-locus model (ACE ID/ACE G2350A/CYP11B2 C-344T) of gene-gene interaction was the best for predicting ESRD risk, and its maximum testing accuracy was 56.08% and maximum cross-validation consistency was 9/10. ESRD risk was higher with the simultaneous occurrence of ACE I/D DD-ACE G2350A AA. AGT, ACE, and CYP11B2 gene polymorphisms are associated with ESRD. Conclusions. The gene-gene interaction effects of ACE I/D, ACE G2350A, and CYP11B2 C-344T polymorphisms are more important than individual factors for ESRD development among Han Chinese.