Association of angiotensinogen M235T gene polymorphism with end-stage renal disease risk: a meta-analysis

Angiotensinogen Gene Missense Polymorphisms (rs699 and rs4762): The Association of End-Stage Renal Failure Risk with Type 2 Diabetes and Hypertension in Egyptians

Type 2 diabetes mellitus (T2DM) and hypertension are common chronic diseases mainly associated with the development and progression of end-stage renal disease (ESRD) leading to morbidity and mortality. Gene polymorphisms linked to the renin–angiotensin (AGT)–aldosterone system (RAAS) were broadly inspected in patients with diabetic nephropathy (DN) and hypertension. This study aimed to investigate the association of AGT gene polymorphisms (rs699 and rs4762) with ESRD in T2DM hypertensive Egyptian patients. Genotyping of rs699 and rs4762 was conducted using the tetra-primers amplification refractory mutation system (ARMS-PCR). The allelic distribution analysis was performed on 103 healthy control subjects, 97 non-ESRD patients, and 104 patients with ESRD. The allelic frequencies of AGT gene polymorphisms (rs4762 and rs699) in all study participants were assessed. For the non-ESRD group, the frequencies of the alleles of AGT-rs4762 (χ² = 31.88, p < 0.001, OR = 5.17, CI 95%: 2.81–9.51) and AGT-rs699 (χ² = 4.85, p = 0.027, OR = 1.56, CI 95%: 1.05–2.33) were significantly associated with the non-ESRD group. However, for the ESRD group, the T allele was significantly higher than that in the controls (χ² = 24.97, p < 0.001, odds ratio (OR) = 4.35, CI 95%: 2.36–8.02). Moreover, AGT (rs699) genotypes showed no significant difference between the ESRD group and controls. In conclusion, AGT gene polymorphisms rs699 and rs4762 were associated with non-ESRD versus controls, without any significant risk observed in all patient groups. However, the AGT (rs4762) variant showed a significant risk in the ESRD group in comparison to controls in Egyptians.

Genetic associations between genes in the renin-angiotensin-aldosterone system and renal disease: a systematic review and meta-analysis

BACKGROUND

Chronic kidney disease (CKD) is defined by abnormalities in kidney structure and/or function present for more than 3 months. Worldwide, both the incidence and prevalence rates of CKD are increasing. The renin-angiotensin-aldosterone system (RAAS) regulates fluid and electrolyte balance through the kidney. RAAS activation is associated with hypertension, which is directly implicated in causation and progression of CKD. RAAS blockade, using drugs targeting individual RAAS mediators and receptors, has proven to be renoprotective.

OBJECTIVES

To assess genomic variants present within RAAS genes, ACE, ACE2, AGT, AGTR1, AGTR2 and REN, for association with CKD.

DESIGN AND DATA SOURCES

A systematic review and meta-analysis of observational research was performed to evaluate the RAAS gene polymorphisms in CKD using both PubMed and Web of Science databases with publication date between the inception of each database and 31 December 2018. Eligible articles included case-control studies of a defined kidney disease and included genotype counts.

ELIGIBILITY CRITERIA

Any paper was removed from the analysis if it was not written in English or Spanish, was a non-human study, was a paediatric study, was not a case-control study, did not have a renal disease phenotype, did not include data for the genes, was a gene expression-based study or had a pharmaceutical drug focus.

RESULTS

A total of 3531 studies were identified, 114 of which met the inclusion criteria. Genetic variants reported in at least three independent publications for populations with the same ethnicity were determined and quantitative analyses performed. Three variants returned significant results in populations with different ethnicities at p<0.05: ACE insertion, AGT rs699-T allele and AGTR1 rs5186-A allele; each variant was associated with a reduced risk of CKD development.

CONCLUSIONS

Further biological pathway and functional analyses of the RAAS gene polymorphisms will help define how variation in components of the RAAS pathway contributes to CKD.

Angiotensin II receptor type 1 A1166C modifies the association between angiotensinogen M235T and chronic kidney disease

Single nucleotide polymorphisms (SNPs) in renin-angiotensin system (RAS) genes are associated with RAS imbalance and chronic kidney disease (CKD). We performed a case-control study and meta-analysis to investigate the association between angiotensinogen (AGT) M235T polymorphism and CKD. A total of 634 patients with end-stage renal disease and 739 healthy controls were studied. We also searched PubMed and the Cochrane Library to identify prospective observational studies published before December 2015. We found that the TT and MT genotypes were associated with a higher risk of CKD than the MM genotype (odds ratio [OR]: 3.56; 95% confidence interval [CI]: 1.14-11.16 and OR: 2.93; 95% CI: 0.91-9.46, respectively). Thirty-eight study populations were included in the meta-analysis. The T allele was associated with a higher risk of CKD than the M allele in all populations (OR: 1.19; 95% CI: 1.08-1.32). The OR was 1.33 in Asians (95% CI: 1.06-1.67) and 1.10 in Caucasians (95% CI: 1.02-1.18). Evaluation of gene-gene and gene-environment interactions using epistasis analysis revealed an interaction between AGT M235T and angiotensin II receptor type 1 A1166C in CKD (OR: 0.767; 95% CI: 0.609-0.965). Genetic testing for CKD in high-risk individuals may be an effective strategy for CKD prevention.

Levels of vitamin D receptor and CYP24A1 in patients with end-stage renal disease

OBJECTIVE

This study was performed to detect the expression of vitamin D receptor (VDR) and cytochrome P450, family 24, subfamily A, polypeptide 1 (CYP24A1) in 24 end stage renal disease (ESRD) patients and 24 healthy controls.

METHOD

In this study, 24 ESRD patients and 24 healthy controls were included.

RESULTS

In our study, the levels of VDR in patients with ESRD were reduced when compared with those from healthy controls (5.20±0.32 vs 8.59±1.03; P<0.01). However, the levels of CYP24A1 in ESRD patients were increased than those from healthy controls (50.18±21 vs 7.78±1.31; P<0.01). Correlation analysis showed that VDR levels were negatively correlated with CYP24A1 (r=-0.723; P<0.01).

CONCLUSION

VDR levels were reduced and CYP24A1 levels were increased in patients with ESRD, and VDR levels were negatively correlated with CYP24A1.

Assessment of the relationship between ACE I/D gene polymorphism and renal allograft survival

BACKGROUND AND OBJECTIVE

The relationship between the angiotensin-converting enzyme (ACE) insertion/deletion (I/D) gene polymorphism and renal allograft survival after renal transplantation from the published reports are still debatable. This study was performed to evaluate the relationship between the ACE I/D gene polymorphism and renal allograft survival after renal transplantation using meta-analysis.

METHOD

Eligible studies were identified from PubMed and Cochrane Library on 1 November 2014, and eligible studies were recruited and synthesized using a meta-analysis methodology.

RESULTS

Twelve investigations were included in this meta-analysis for the assessment of the relationship between the ACE I/D gene polymorphism and renal allograft survival. In this meta-analysis, the ACE I/D gene polymorphism was not associated with renal allograft survival after renal transplantation for overall populations, Caucasians, Brazilians and Africans. Interestingly, the ACE D allele and DD genotype were associated with renal allograft survival after renal transplantation in the Asian population.

CONCLUSIONS

ACE D allele and DD genotype were associated with renal allograft survival after renal transplantation in the Asian population. However, more studies should be performed to confirm this association.

M235T polymorphism in the AGT gene and A/G(I8-83) substitution in the REN gene correlate with end-stage renal disease

BACKGROUND/AIMS

This study aimed at investigating if M235T polymorphism in the AGT gene and A/G(I8-83) polymorphism in the REN gene correlate with end-stage renal disease (ESRD).

METHODS

We analyzed 173 ESRD patients and 329 individuals with normal kidney function for differences in the genotype distribution of AGT-M235T and REN-A/G(I8-83) polymorphisms between the two groups. The data for cases and controls were compared using the χ(2) test.

RESULTS

We found significantly higher levels of serum creatinine and CRP in cases in comparison to controls (p < 0.0001). Data comparison showed a significant association of AGT M235T substitution with ESRD in the dominant model (p = 0.008) and in the comparison of the heterozygous substitution with the homozygous common genotype (p = 0.005). Similarly, REN A/G(I8-83) polymorphism showed a significant difference in the distribution of genotypes between cases and controls (p < 0.038) such that a heterozygous substitution was significantly more common in the ESRD cases in comparison to the homozygous common genotype (p = 0.023).

CONCLUSION

We conclude that heterozygous substitutions at the AGT M235T and REN A/G(I8-83) loci correlate significantly with ESRD in a north Indian population.

Association of AGT M235T gene polymorphism with HSP/HSPN risk

To evaluate the association between angiotensinogen (AGT) gene polymorphism and the risk of Henoch-Schönlein purpura (HSP)/Henoch-Schönlein purpura nephritis (HSPN) we searched the eligible studies through Pub Med, Embase, Cochrane, and China National Knowledge Infrastructure (CNKI) databases according to predefined criteria. A random-effects model was used to calculate the combined odds ratios (ORs) and its corresponding 95% confidence interval (CI). Five studies were recruited for the analysis of the association between AGT M235T gene polymorphism and HSP/HSPN risk. M allele was associated with lower risk of HSP in adult (p = 0.050), TT genotype was associated with the susceptibility to HSP in adult (p = 0.039). AGT M235T gene polymorphism was not associated with HSP risk in children. No marked association was observed between AGT M235T gene polymorphism and HSPN risk. No evidence of publication bias was observed. In conclusion, M allele might be a protective factor against the HSP risk in adult, TT genotype might be a risk factor for the susceptibility to HSP in adult. However, further larger studies should be performed in the future.

Developments in renal pharmacogenomics and applications in chronic kidney disease

Chronic kidney disease (CKD) has shown an increasing prevalence in the last century. CKD encompasses a poor prognosis related to a remarkable number of comorbidities, and many patients suffer from this disease progression. Once the factors linked with CKD evolution are distinguished, it will be possible to provide and enhance a more intensive treatment to high-risk patients. In this review, we focus on the emerging markers that might be predictive or related to CKD progression physiopathology as well as those related to a different pattern of response to treatment, such as inhibitors of the renin–angiotensin system (including angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers; the vitamin D receptor agonist; salt sensitivity hypertension; and progressive kidney-disease markers with identified genetic polymorphisms). Candidate-gene association studies and genome-wide association studies have analyzed the genetic basis for common renal diseases, including CKD and related factors such as diabetes and hypertension. This review will, in brief, consider genotype-based pharmacotherapy, risk prediction, drug target recognition, and personalized treatments, and will mainly focus on findings in CKD patients. An improved understanding will smooth the progress of switching from classical clinical medicine to gene-based medicine.

Association of glutathione S-transferase P1 gene polymorphism with the risk of small-cell carcinoma of lung cancer

The conclusions of the published reports on the relationship between glutathione S-transferase P1 (GSTP1) gene polymorphism and the risk of small-cell carcinoma of lung cancer are still debated. GSTP1 is one of the important mutant sites reported at present. This meta-analysis was performed to evaluate the association between GSTP1 and the risk of small-cell carcinoma of lung cancer. The association investigations were identified from PubMed and Cochrane Library, and eligible studies were included and synthesized using meta-analysis method. Ten reports were included into this meta-analysis for the association of GSTP1 A/G gene polymorphism and small-cell carcinoma of lung cancer. The G allele and GG genotype were not associated with the susceptibility of risk of small-cell carcinoma in overall populations, East-Asians and Turkish population. However, there was an association between GG genotype with the risk of small-cell carcinoma in Caucasians. In conclusion, GG genotype was associated with the risk of small-cell carcinoma in Caucasian patients with lung cancer. However, GSTP1 A/G gene polymorphism is not associated with the susceptibility of small-cell carcinoma in overall populations, East-Asians and Turkish population.

Association of vitamin D receptor BsmI (rs1544410) gene polymorphism with the intact parathyroid hormone (iPTH) level among patients with end-stage renal disease

Association of vitamin D receptor (VDR) BsmI (rs1544410) gene polymorphism with the intact parathyroid hormone (iPTH) level among patients with end-stage renal disease (ESRD) from the published reports is still conflicting. This meta-analysis was performed to evaluate the relationship between VDR BsmI (rs1544410) gene polymorphism and the iPTH level among patients with ESRD. The association studies were identified from PubMed, and Cochrane Library on 1 March 2014, and eligible investigations were included and synthesized using meta-analysis method. Six reports were recruited into this meta-analysis for the association of VDR BsmI gene polymorphism with iPTH level among patients with ESRD. In this meta-analysis, the iPTH level in ESRD patients carrying BsmI Bb genotype was higher than that in ESRD patients carrying bb genotype in overall populations (Bb versus bb: OR = 61.40, 95% CI: 19.65-103.16, p = 0.004). However, the iPTH level in ESRD patients carrying BB genotype was not significant different from that in ESRD patients with Bb genotype and bb genotype in overall populations (BB versus Bb: OR = -18.30, 95% CI: -126.28-89.69, p = 0.74; BB versus bb: OR = 22.85, 95% CI: -70.81-116.51, p = 0.63). Furthermore, the results for Caucasians were similar to those in overall populations. In conclusion, the iPTH level in ESRD patients carrying BsmI Bb genotype was higher than that in ESRD patients carrying bb genotype in overall populations and in Caucasians. However, more studies should be conducted to confirm it.

GSTT1 polymorphism and the risk of developing prostate cancer

A possible association between glutathione S-transferase theta 1 gene (GSTT1) polymorphism and the risk of developing prostate cancer is currently hotly debated, but evidence from various epidemiologic studies remains unclear. This investigation was performed to assess whether an association between GSTT1 polymorphism and prostate cancer risk exists by using meta-analysis to combine comparable studies, thereby increasing sample size and statistical significance, as well as to identify patterns in various studies. The association reports were identified from the PubMed database and the Cochrane Library on March 1, 2013, and data from eligible studies (from 1999-2012) were synthesized. Thirty-eight reports were included in this meta-analysis on the association of the null genotype of GSTT1 with prostate cancer risk. No solid association between the GSTT1 null genotype and prostate cancer risk could be established for the overall population (odds ratio = 1.11, 95% confidence interval: 0.97, 1.27; P = 0.13). However, the GSTT1 null genotype was distinctly associated with prostate cancer risk in Caucasians (odds ratio = 1.24, 95% confidence interval: 1.03, 1.48, P = 0.02). In conclusion, the GSTT1 null genotype is associated with prostate cancer risk in Caucasians, but not in the overall population.

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.

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.

Dynamic CCAAT/enhancer binding protein-associated changes of DNA methylation in the angiotensinogen gene

DNA methylation patterns are maintained in adult somatic cells. Recent findings, however, suggest that all methylation patterns are not preserved. We demonstrate that stimulatory signals can change the DNA methylation status at a CCAAT/enhancer binding protein (CEBP) binding site and a transcription start site and activate expression of the angiotensinogen gene (AGT). A CEBP binding site in the human AGT promoter was hypomethylated in tissues with high expression of AGT, but not in those with low expression. The transcriptional activity of AGT promoter sequences cloned into a reporter plasmid depended on DNA methylation. In cultured human cells, interleukin 6 stimulation caused DNA demethylation around a CEBP binding site and a transcription start site; demethylation was accompanied by increased CEBP-β recruitment and chromatin accessibility of the AGT promoter. DNA methylation activity decreased in the nucleus. Excess circulating aldosterone upregulated AGT expression and was accompanied by DNA hypomethylation around a CEBP binding site and a transcription start site in human visceral adipose tissue. High salt intake led to upregulation of Agt expression, DNA hypomethylation around 2 CEBP binding sites and a transcription start site, and decreased DNA methylation activity in rat visceral adipose tissue. Taken together, CEBP binding initiates chromatin relaxation and transcription, which are followed by DNA demethylation around a CEBP binding site and a transcription start site in the AGT promoter. Decreased DNA methylation activity in the nucleus may play a role in DNA demethylation. DNA demethylation switches the phenotype of AGT expression from an inactive to an active state.

Association of aldosterone synthase (CYP11B2) gene -344T/C polymorphism with the risk of primary chronic glomerulonephritis in the Polish population

INTRODUCTION

We evaluate whether angiotensinogen AGT M235T (rs699), angiotensin-converting enzyme ACE (I/D) (rs4646994) and aldosterone synthase CYP11B2 -344C/T (rs1799998) polymorphisms can be genetic risk factors of chronic glomerulonephritis (GN) in the Polish population.

MATERIALS AND METHODS

The study was conducted in 140 patients with primary chronic GN: mesangial proliferative GN (MesPGN) (n = 49), IgA nephropathy (IgAN) (n = 31), membranous nephropathy (MN) (n = 27), focal segmental glomerulosclerosis (FSGS) (n = 25), membranoproliferative GN (MPGN) (n = 4), and minimal change disease (MCD) (n = 4), and controls (n = 187). Genotypes were determined by HRM curve analysis for AGT M235T, by PCR and agarose gel separation for ACE (I/D), and by PCR-RFLP for CYP11B2 -344C/T.

RESULTS

We found a significant association of the CYP11B2 -344C/T polymorphism in the recessive model with all subtypes of GN (OR = 1.925 (95% CI = 1.152-3.219, p = 0.0118, p(corr) = 0.0354)). We also observed that the CYP11B2 -344C/T polymorphism in the recessive model may also be an independent significant risk factor of IgAN (OR = 2.743 (95% CI = 1.219-6.172, p = 0.0122, p(corr) = 0.0366)), FSGS (OR = 2.895 (95% CI = 1.200-6.985, p = 0.0145, p(corr) = 0.0435)), and all proliferative GNs (MesPGN, IgAN, MPGN) (OR = 2.171 (95% CI = 1.211-3.894, p = 0.0084, p(corr) = 0.0252)).

CONCLUSION

Our results suggest that the CYP11B2 -344C/T polymorphism might be an independent risk factor of IgAN, FSGS and all proliferative chronic GNs.