Genetic polymorphism of ACE and the angiotensin II type1 receptor genes in children with chronic kidney disease

Structural effect of the H992D/H418D mutation of angiotensin-converting enzyme in the Indian population: implications for health and disease

The Non synonymous SNPs (nsSNPs) of the renin-angiotensin-system (RAS) pathway, unique to the Indian population were investigated in view of its importance as an endocrine system. nsSNPs of the RAS pathway genes were mined from the IndiGenome database. Damaging nsSNPs were predicted using SIFT, PredictSNP, SNP and GO, Snap2 and Protein Variation Effect Analyzer. Loss of function was predicted based on protein stability change using I mutant, PremPS and CONSURF. The structural impact of the nsSNPs was predicted using HOPE and Missense3d followed by modeling, refinement, and energy minimization. Molecular Dynamics studies were carried out using Gromacsv2021.1. 23 Indian nsSNPs of the RAS pathway genes were selected for structural analysis and 8 were predicted to be damaging. Further sequence analysis showed that HEMGH zinc binding motif changes to HEMGD in somatic ACE-C domain (sACE-C) H992D and Testis ACE (tACE) H418D resulted in loss of zinc coordination, which is essential for enzymatic activity in this metalloprotease. There was a loss of internal interactions around the zinc coordination residues in the protein structural network. This was also confirmed by Principal Component Analysis, Free Energy Landscape and residue contact maps. Both mutations lead to broadening of the AngI binding cavity. The H992D mutation in sACE-C is likely to be favorable for cardiovascular health, but may lead to renal abnormalities with secondary impact on the heart. H418D in tACE is potentially associated with male infertility.Communicated by Ramaswamy H. Sarma.

Haematological Indicators of Response to Erythropoietin Therapy in Chronic Renal Failure Patients on Haemodialysis: Impact of Angiotensin-Converting Enzyme rs4343 Gene Polymorphism

PURPOSE

This is the first cross-sectional study studying the changes in haematological indicators of the response to recombinant human erythropoietin (rHuEPO) therapy in chronic renal failure (CRF) patients on haemodialysis (HD) stratified according to ACE G2350A (rs4343) gene polymorphism.

DESIGN

An observational cross-sectional study.

SETTING

Nephrology department and Biochemistry and molecular biology department, faculty of medicine, Cairo University.

PATIENTS

A total of 256 CRF patients on HD for at least six months (162 male and 103 female) and 160 healthy subjects (122 male and 38 female) were recruited in the current study after signing a consent form. ACE G2350A (rs4343) Insertion/Deletion (I/D) was tested, the association between ACE G2350A (RS4343) gene polymorphisms and patients response to rHuEpo was evaluated.

RESULTS

ACE G2350A (rs4343) I/D was the most prevalent genotype, while I/I genotype was the lowest prevalent among patient or control subjects included in the study. D allele is the most prevalent allele, either among patients or the control group. Hemoglobin (Hb) level in patients with I/I and Deletion/Deletion (D/D) genotype was significantly higher compared to those with I/D genotype (P = 0.012 and P = 0.005, respectively). Serum iron in the I/D genotype was significantly higher than those with either I/I or D/D genotype (P = 0.045 and P = 0.018, respectively). Angiotensin-converting enzyme (ACE) content, total leukocytic count (TLC), and soluble erythropoietin receptor (sEpoR) were independent predictors of Hb level. The ACE gene, TLC, and serum iron were the independent factors that may affect the Haematocrit (Hct) level. ACE G2350A (rs4343) gene polymorphisms may affect the HD patient's responses to rHuEPOs.

CONCLUSION

In HD patients, screening for ACE G2350A (rs4343) gene polymorphisms before rHuEpo administration may help predict patient response.

ACE gene polymorphism and its association with serum erythropoietin and hemoglobin ‎in Iraqi hemodialysis patients

Purpose

To evaluate the frequencies of angiotensin-converting enzyme gene ‎polymorphism in ‎Iraqi hemodialysis patients and to examine the association ‎between this polymorphism and ‎serum erythropoietin and hemoglobin levels.‎.

Methods

In this study, 70 chronic renal failure Iraqi patients on ‎maintenance ‎hemodialysis (patient group) and 20 healthy subjects (control ‎group) were genotyped for ‎angiotensin-converting enzyme gene polymorphism. The distribution of genotype and allele ‎frequencies of this polymorphism in ‎these subjects were also evaluated.‎.

Results

The distribution of angiotensin-converting enzyme genotypes between ‎groups was ‎similar, and the ID genotype was the most frequent, followed by DD and II ‎genotypes (‎50%‎, ‎37%‎, and ‎13%). The control group ‎had a nonsignificant difference in serum ‎erythropoietin levels among different angiotensin-converting enzyme genotypes, ‎while patients with ID and DD genotypes displayed significant ‎elevation in ‎serum erythropoietin with time. No significant differences in hemoglobin ‎levels ‎were observed in patient and control groups. A significant positive correlation ‎was ‎observed between serum erythropoietin and hemoglobin in the control group ‎with different ‎angiotensin-converting enzyme genotypes, while a nonsignificant ‎negative correlation was ‎observed in the patient group throughout the study. ‎.

Conclusions

Chronic kidney disease did not significantly alter angiotensin-converting enzyme ‎genotypes, and angiotensin-converting enzyme gene ‎polymorphism had a significant effect on ‎serum erythropoietin levels and a non‎significant effect on hemoglobin levels. ‎.

ACE I/D and MMP-7 A-181G variants and the risk of end stage renal disease

The variants of angiotensin converting enzyme (ACE) and matrix metalloproteinases (MMPs) genes might be involved in the pathogenesis of end stage renal disease (ESRD) and hypertension. We studied the ACE insertion/deletion (I/D) and MMP-7 A-181G variants in 99 unrelated ESRD patients and 117 individuals without renal complications from Western Iran with Kurdish ethnic background. The frequency of ACE I/D variants was not significantly different between ESRD patients and controls. However, the presence of ACE D allele increased the risk of hypertension in ESRD patients by 2.14-fold (P=0.036). The MMP-7 -181 AG genotype increased the risk of ESRD by 2.04 times (P=0.026). The present study indicated the absence of an association between the ACE I/D polymorphism with the risk of ESRD. However, the ACE D allele increased the risk of hypertension in ESRD patients. Also, the present study suggests a role for MMP-7 AG genotype in the pathogenesis of ESRD.

Prevalence of angiotensin converting enzyme (ACE) gene insertion/deletion polymorphism in South Indian population with hypertension and chronic kidney disease

Context:

Chronic Kidney Disease (CKD) is associated with a high risk of developing further severe complications such as, cardiovascular disease and eventually End Stage Renal Disease (ESRD) leading to death. Hypertension plays a key role in the progression of renal failure and is also a chief risk factor for the occurrence of End Stage Renal Disease (ESRD).

Aim:

This study investigates the possible association of insertion (I) and deletion (D) polymorphism of ACE gene in patients of Chronic Kidney Disease (CKD) with and without hypertension (HT).

Settings and Design:

Total 120 participants with 30 members in each group (Control, HT, CKD and CKD-HT) were chosen followed by informed consent.

Materials and Methods:

Blood samples were collected and subjected to biochemical analyses and nested PCR amplification was performed to genotype the DNA, for ACE I/D using specific primers.

Statistical Analysis:

Statistical analyses were performed using SPSS version 13. Allele and genotypic frequency was calculated by direct gene counting method. Comparison of the different genotypes was done by using Chi square test. Odd's ratios were calculated with a 95% confidence interval limit.

Results:

The ACE genotype were distributed as II, 27 (90%); DD, 2 (6.67%) and ID, 1 (3.33%) in control, II, 1 (3.33%); DD, 5 (16.67%) and ID, 24 (80%) in HT, II, 4 (13.33%); DD, 24 (80%) and ID, 2 (6.67%) in CKD and II, 0 (0%); DD, 2 (6.67%) and ID, 28 (93.33%) in CKD-HT group.

Conclusions:

D allele of ACE gene confers a greater role in genetic variations underlying CKD and hypertension. This result suggest that CKD patients should be offered analysis for defects in ACE I/D polymorphisms, especially if they are hypertensive.

Genetic Considerations in Pediatric Chronic Kidney Disease

Chronic kidney disease (CKD) in children is an irreversible process that, in some cases, may lead to end-stage renal disease. The majority of children with CKD have a congenital disorder of the kidney or urological tract arising from birth. There is strong evidence for both a genetic and epigenetic component to progression of CKD. Utilization of gene-mapping strategies, ranging from genome-wide association studies to single-nucleotide polymorphism analysis, serves to identify potential genetic variants that may lend to disease variation. Genome-wide association studies evaluating population-based data have identified different loci associated with CKD progression. Analysis of single-nucleotide polymorphisms on an individual level suggests that secondary systemic sequelae of CKD are closely related to dysfunction of the cardiovascular-inflammatory axis and may lead to advanced cardiovascular disease through abnormal vascular calcification and activation of the renin-angiotensin system. Similarly, genetic variants affecting cytokine control, fibrosis, and parenchymal development may modulate CKD through development and acceleration of renal interstitial fibrosis. Epigenetic studies evaluate modification of the genome through DNA methylation, histone modification, or RNA interference, which may be directly influenced by external or environmental factors directing genomic expression. Lastly, improved understanding of the genetic and epigenetic contribution to CKD progression may allow providers to identify a population at accelerated risk for disease progression and apply novel therapies targeted at the genetic mechanism of disease.

Susceptibility and progression of end stage renal disease are not associated with angiotensin II type 1 receptor gene polymorphism

CONTEXT

The role of the angiotensin II type 1 receptor (AT1R) gene polymorphism, A1166C, has been shown to be associated with end stage renal disease (ESRD) and its progression. There is also some evidence that HLA class II alleles are associated with ESRD independent of other factors.

OBJECTIVE

To examine the association between AT1R gene polymorphism in the susceptibility and progression to ESRD in patients with chronic renal failure and to investigate if the AT1R genotypes and HLA-DR alleles predict the time to ESRD.

MATERIALS AND METHODS

Genotyping was performed in 50 ESRD patients and 44 control subjects for the AT1R A1166C gene polymorphism using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). ESRD patients were examined for HLA-DRB1 alleles according to a reverse hybridization line probe assay.

RESULTS

Allele and genotype frequencies of the AT1R polymorphism did not differ significantly between ESRD patients and controls. Furthermore, there was no association between the AT1R gene polymorphism or HLA-DRB1 alleles with the time to the occurrence of end stage failure.

DISCUSSION AND CONCLUSION

We concluded that the AT1R genotype does not contribute to the genetic susceptibility of ESRD and is not associated with progression of chronic kidney failure to ESRD.

Gene polymorphisms of adducin GLY460TRP, ACE I/D, AND AGT M235T in pediatric hypertension patients

BACKGROUND

Hypertension is a major global public health problem that affects both pediatric and adult populations. ACE I/D, AGT M235T, and ADD Gly460Trp polymorphisms are thought to be associated with primary hypertension. In the present study, we examined the frequency of these polymorphisms in a pediatric population with secondary hypertension.

MATERIAL AND METHODS

Included in the study were 58 hypertensive and 58 normotensive pediatric patients. ACE I/D and AGT M235T polymorphisms are determined by conventional PCR; ADD Gly460Trp polymorphism was investigated using PCR amplification of genomic DNA.

RESULTS

There were significant differences between the control group and pediatric hypertensive group in terms of ACE I/D (P<0.05) and AGT M235T (P<0.05) polymorphisms, but there were no differences in ADD Gly460Trp (P>0.05) polymorphism.

CONCLUSIONS

We suggest that RAS gene polymorphisms (ACE-I/D, AGT M235T) are significantly associated with susceptibility to diseases that lead to secondary hypertension.

The role of genetic polymorphisms of the Renin-Angiotensin System in renal diseases: A meta-analysis

Renal failure has a complex phenotype resulting from an underlying kidney disease as well as environmental and genetic factors. In the present study we performed a systematic review and meta-analyses to evaluate the association of the A1166C polymorphism of Angiotensin II type 1 Receptor gene (AGTR1) with Chronic Kidney Disease (CKD), End Stage Renal Disease (ESRD), IgA Nephropathy (IgAN) and Vesicoureteral Reflux (VUR) as well as the association of A1332G polymorphism of Angiotensin II type 2 Receptor (AGTR2) gene with Vesicoureteral Reflux (VUR). We found that neither AGTR1 Α1166C, nor AGTR2 A1332G polymorphisms were significantly associated with any of the aforementioned renal diseases, suggesting that they cannot be used as predictive markers in either general or subgroup ethnic populations.

Angiotensin-converting enzyme insertion/deletion polymorphism associated with allergic rhinitis susceptibility: evidence from 1410 subjects

BACKGROUND AND OBJECTIVE

Whether the insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme (ACE) gene increases susceptibility to allergic rhinitis (AR) is still undetermined. Therefore, this meta-analysis was performed to systematically assess the possible association between them.

METHODS

The OVID, Medline, Embase, Web of Science, CNKI and Wangfang databases were searched to identify the eligible studies focusing on the association between ACE I/D polymorphism and susceptibility to AR.

RESULTS

A total of 1410 subjects from six studies were subjected to meta-analysis. In the overall analysis, ACE I/D polymorphism had a statistically significant association with increased AR risk under all genetic models (p<0.05). In the subgroup analysis by ethnicity, significant elevated AR risks were associated with ACE I/D polymorphism in Asians under all genetic models (p<0.05) and in Caucasians under under allele contrast, homozygous comparison and recessive models (p<0.05). In the subgroup analysis by age, ACE I/D polymorphism was associated with significant elevated risks of AR in adults (p<0.05) but not in children (p>0.05) under all genetic models.

CONCLUSIONS

The ACE I/D polymorphism may be a risk factor for AR and studies with large sample size and representative population are warranted to verify this finding.