Association between angiotensinogen T174M polymorphism and the risk of diabetic nephropathy: A meta-analysis

Genetic Polymorphism in Angiotensinogen and Its Association with Cardiometabolic Diseases

Angiotensinogen (AGT) is one of the most significant enzymes of the renin-angiotensin-aldosterone system (RAAS) which is involved in the regulation and maintenance of blood pressure. AGT is involved in the production of angiotensin I which is then converted into angiotensin II that leads to renal homeostasis. However, various genetic polymorphisms in AGT have been discovered in recent times which have shown an association with various diseases. Genetic polymorphism increases the level of circulating AGT in blood which exaggerates the effects produced by AGT. The associated diseases occur due to various effects produced by increased AGT levels. Several cardiovascular diseases including myocardial infarction, coronary heart disease, heart failure, hypertrophy, etc. are associated with AGT polymorphism. Other diseases such as depression, obesity, diabetic nephropathy, pre-eclampsia, and liver injury are also associated with some variants of AGT gene. The most common variants of AGT polymorphism are M235T and T174M. The two variants are associated with many diseases. Some other variants such as G-217A, A-6G, A-20C and G-152A, are also present but they are not as significant as that of M235T and T174M variants. These variants increase the level of circulating AGT and are associated with prevalence of different diseases. These diseases occur through various pathological pathways, but the initial reason remains the same, i.e., increased level of AGT in the blood. In this article, we have majorly focused on how genetic polymorphism of different variants of AGT gene is associated with the prevalence of different diseases.

The impact of angiotensin converting enzyme insertion/deletion gene polymorphism on diabetic kidney disease: A debatable issue

OBJECTIVE

The objective of this study was to evaluate the influence of ACE I/D gene polymorphisms on diabetic kidney disease (DKD) risk.

METHODS

All eligible investigations were identified, the number of various genotype in the case and control group were reviewed. The pooled analysis was performed using Stata software.

RESULTS

In overall subjects, 24,321 participants with 12,961 cases and 11,360 controls were included. the pooled analysis showed a significant link between D allele, DD or II genotype and DKD risk (D versus I: OR=1.316, 95% CI: 1.213-1.427, P=0.000; DD versus ID+II: OR=1.414, 95% CI: 1.253-1.595, P=0.000; II versus DD+ID: OR=0.750, 95% CI: 0.647-0.869, P=0.000). The subgroup pooled analysis showed that ACE I/D gene polymorphism was correlated with DKD both in Asian and in Chinese population. In addition, ACE I/D gene polymorphism was correlated with type 2 DKD (D versus I: OR=1.361, 95% CI: 1.243-1.490, P=0.000; DD versus ID+II: OR=1.503, 95% CI: 1.310-1.726, P=0.000; II versus DD+ID: OR=0.738, 95% CI: 0.626 -0.870, P=0.000). However, there was no obvious correlation in Caucasian subjects and type 1 diabetic patients.

CONCLUSION

ACE I/D polymorphisms were correlated with DKD in Asian and type 2 diabetic populations. ACE D allele/DD genotype might be a risk factor, while ACE II genotype might be a protective factor for DKD.

The impact of angiotensin converting enzyme insertion/deletion gene polymorphism on diabetic kidney disease: A debatable issue

OBJECTIVE

The objective of this study was to evaluate the influence of ACE I/D gene polymorphisms on diabetic kidney disease (DKD) risk.

METHODS

All eligible investigations were identified, the number of various genotype in the case and control group were reviewed. The pooled analysis was performed using Stata software.

RESULTS

In overall subjects, 24,321 participants with 12,961 cases and 11,360 controls were included. the pooled analysis showed a significant link between D allele, DD or II genotype and DKD risk (D versus I: OR=1.316, 95% CI: 1.213-1.427, P=0.000; DD versus ID+II: OR=1.414, 95% CI: 1.253-1.595, P=0.000; II versus DD+ID: OR=0.750, 95% CI: 0.647-0.869, P=0.000). The subgroup pooled analysis showed that ACE I/D gene polymorphism was correlated with DKD both in Asian and in Chinese population. In addition, ACE I/D gene polymorphism was correlated with type 2 DKD (D versus I: OR=1.361, 95% CI: 1.243-1.490, P=0.000; DD versus ID+II: OR=1.503, 95% CI: 1.310-1.726, P=0.000; II versus DD+ID: OR=0.738, 95% CI: 0.626 -0.870, P=0.000). However, there was no obvious correlation in Caucasian subjects and type 1 diabetic patients.

CONCLUSION

ACE I/D polymorphisms were correlated with DKD in Asian and type 2 diabetic populations. ACE D allele/DD genotype might be a risk factor, while ACE II genotype might be a protective factor for DKD.

AGT rs4762 is associated with diastolic blood pressure in Mexicans with diabetic nephropathy

AIMS

Since angiotensinogen has a pivotal role in the renin-angiotensin-aldosterone system, the analysis of polymorphisms of the angiotensinogen (AGT) gene could help explain its potential involvement in hypertension and diabetic nephropathy (DN) pathogenesis. For that reason, we investigated 1) the association of AGT rs4762 with blood pressure (BP) and kidney function-related traits and 2) the interaction effect of AGT rs4762 with DN on BP and kidney function-related traits in 546 Mexican adults with type 2 diabetes (T2D).

METHODS

We enrolled 546 unrelated Mexican patients with T2D (350 cases with DN and 196 controls without DN). AGT rs4762 was genotyped in all participants using TaqMan technology (effect allele: A). BP and kidney function-related traits, including serum urea and creatinine, urinary albumin, urine albumin to urine creatinine ratio (ACR), and glomerular filtration rate, were studied. DN was defined as having a previous diagnosis of T2D and an ACR ≥ 30 mg/g. The association between these parameters was investigated using logistic regression with adjustment for covariates.

RESULTS

AGT rs4762 A allele was significantly associated with diastolic blood pressure (N = 546, β = 1.243 ± 0.918, p = 0.029). A significant interaction between DN and AGT rs4762 was also observed in relation to diastolic blood pressure (DBP) (N = 546, β = 0.930 ± 0.433, p=0.032). A follow-up analysis of simple effects particularly revealed a positive association between AGT rs4762 A allele and DBP only in patients with diabetic nephropathy (N = 350, β = 2.837 ± 1.267, p = 0.026).

CONCLUSION

Our results evidence that, although AGT rs4762 is not associated with DN, the AGT rs4762 A allele is positively associated with DBP in the Mexican population with DN.

SLC6A4 gene L/S polymorphism and susceptibility to pulmonary arterial hypertension: a meta-analysis

Objective

To investigate the association between the solute carrier family 6 member 4 (SLC6A4) gene L/S polymorphism and pulmonary arterial hypertension (PAH).

Methods

The relevant literature was retrieved from the PubMed® database and the data were extracted. STATA® version 12.0 software was used to calculate pooled odds ratios (ORs) and 95% confidence intervals (CI).

Results

Eight case–control studies qualified for inclusion in the meta-analysis. These studies included 1215 cases and 936 control subjects. There was no significant association between the SLC6A4 gene L/S polymorphism and PAH risk in the total population (LL versus SS: OR 1.83, 95% CI 0.95, 3.51; LS versus SS: OR 1.37, 95% CI 0.93, 2.02; dominant model: OR 1.38, 95% CI 0.97, 1.97; recessive model: OR 1.54, 95% CI 0.84, 2.83). Subgroup analysis based on study quality scores and Hardy–Weinberg equilibrium also showed no significant association.

Conclusion

The findings of this meta-analysis suggest that the SLC6A4 gene L/S polymorphism is unlikely to be related to PAH risk. Well-designed studies with more participants will be required to validate these results.

Association of polymorphism genes , , and with risk of hyperinsulinism and insulin resistance in the Kazakh population

Hyperinsulinism and insulin resistance are closely associated with several common diseases including type 2 of diabetes, cardiovascular diseases, and metabolic syndrome. The present study aimed to determine the association between hyperinsulinism, insulin resistance and the polymorphism of genes, including angiotensin II receptor type 1 (AGTR1), angiotensinogen (AGT), β2-adrenoreceptor (ADRB2) and lipoprotein lipase (LPL), in the Kazakh population. The design of the current research was a case-control study, involving 460 subjects (age range, 18-65 years). For every subject, plasma glucose, insulin, total cholesterol, triglycerides, high-density lipoprotein, low-density lipoprotein, apolipoprotein B and apolipoprotein A1 were examined. Moreover, reverse transcription-quantitative PCR was conducted to detect the polymorphism genes LPL Ser447Ter, ADRB2 Gln27Glu, AGT Thr174Met and AGTR1 A1166C. Hyperinsulinism was considered when the insulin level was elevated >24.9 IU/ml. The homeostasis model assessment insulin resistance (HOMA-IR) was used to evaluate insulin resistance. The subjects were divided into hyperinsulinism (17 men and 24 women) and normal level insulin (214 men and 205 women) groups, which were also split into insulin resistance group (HOMA-IR >2.7; 80 men and 105 women) and those without insulin resistance group (151 men and 124 women). The results suggested that LPL Ser447Ter (rs328) allele G was associated with a lower risk of hyperinsulinism (P=0.037). Furthermore, polymorphisms of genes ADRB2 Gln27Glu (rs1042714), AGT Thr174Met (rs4762) and AGTR1 A1166C (rs5186) were not associated with hyperinsulinism and insulin resistance in the Kazakh population. No interaction was identified between LPL Ser447Ter, ADRB2 Gln27Glu, AGT Thr174Met and AGTR1 A1166C. Therefore, the results indicated that haplotype combinations were not associated with insulin resistance.