Association of common variants in NPPA and NPPB with blood pressure does not translate into kidney damage in a general population study

ASA Status, NPPA/NPPB Haplotype and Coronary Artery Disease Have an Impact on BNP/NT-proBNP Plasma Levels

Plasma concentrations of natriuretic peptides (NP) contribute to risk stratification and management of patients undergoing non-cardiac surgery. However, genetically determined variability in the levels of these biomarkers has been described previously. In the perioperative setting, genetic contribution to NP plasma level variability has not yet been determined. A cohort of 427 patients presenting for non-cardiac surgery was genotyped for single-nucleotide polymorphisms (SNPs) from the NPPA/NPPB locus. Haplotype population frequencies were estimated and adjusted haplotype trait associations for brain natriuretic peptide (BNP) and amino-terminal pro natriuretic peptide (NT-proBNP) were calculated. Five SNPs were included in the analysis. Compared to the reference haplotype TATAT (rs198358, rs5068, rs632793, rs198389, rs6676300), haplotype CACGC, with an estimated frequency of 4%, showed elevated BNP and NT-proBNP plasma concentrations by 44% and 94%, respectively. Haplotype CGCGC, with an estimated frequency of 9%, lowered NT-proBNP concentrations by 28%. ASA classification status III and IV, as well as coronary artery disease, were the strongest predictors of increased NP plasma levels. Inclusion of genetic information might improve perioperative risk stratification of patients based on adjusted thresholds of NP plasma levels.

Blood pressure and urinary sodium excretion in relation to 16 genetic polymorphisms in the natriuretic peptide system in Chinese

We systematically investigated the association between single nucleotide polymorphisms (SNPs) in the natriuretic peptide system (NPPA, NPPB, NPPC, NPRA, NPRC, and Corin genes) and blood pressure in a Chinese population. The study population was recruited from a mountainous area 500 km south of Shanghai from 2003 to 2009. Using the ABI SNapShot method, we first genotyped 951 subjects enrolled in 2005 for 16 SNPs and then the remaining 1355 subjects as validation for 5 SNPs selected from the primary study. Overall, the association of the studied genetic polymorphisms with blood pressure and urinary excretion of cations was weak or non-significant. However, in the primary study, there was significant (Pint = 0.003) interaction between the rs198358 polymorphism and age in relation to diastolic blood pressure. After adjustment for covariates, diastolic blood pressure was significantly higher in the G allele carriers than AA homozygotes in 176 subjects aged 60 years or older (77.8 ± 1.72 vs 73.9 ± 1.54 mmHg, P = 0.001). In the primary combined with validation studies, this interaction remained statistically significant (Pint = 0.02). The odds ratio of hypertension for carrying the G allele versus AA homozygotes was 1.25 (95% CI: 1.03-1.52; P = 0.03) in all subjects, and 0.85 (0.51-1.41; P = 0.53), 1.30 (0.98-1.73; P = 0.06), and 1.45 (0.95-2.22; P = 0.08) in the subjects younger than 40 years, 40-59 years, and 60 years or older, respectively. Some of the genetic polymorphisms in the natriuretic peptide system might be associated with blood pressure. However, not only the size, but also the direction of the association may change with age.

The atrial natriuretic peptide genetic variant rs5068 is associated with a favorable cardiometabolic phenotype in a Mediterranean population

OBJECTIVE

We hypothesized that the minor allele of the atrial natriuretic peptide (ANP) genetic variant rs5068 is associated with a favorable cardiometabolic phenotype in a general Mediterranean population.

RESEARCH DESIGN AND METHODS

We genotyped a random sample of the residents of Ventimiglia di Sicilia, Sicily, for rs5068.

RESULTS

Genotype frequencies of rs5068 are AA, 93.5%; AG, 6.4%; and GG, 0.1%. All subsequent analyses are AA versus AG+GG. After adjusting for age and sex, the minor G allele is associated with lower BMI (estimate [SE]: -1.7 kg/m(2) [0.8], P = 0.04). In the AG+GG group, males with HDL cholesterol levels <40 mg/dL are less frequent (P = 0.05) and obesity tends to be less prevalent (P = 0.07). Importantly, the G allele is associated with a lower prevalence of metabolic syndrome (P = 0.02). After adjusting for BMI, the above associations were attenuated. Independently of age, sex, and BMI, the minor allele is also associated with lower systolic blood pressure (-6.0 mmHg [2.5], P = 0.02) and lower prevalence of hypertension (odds ratio 0.41 [95% CI 0.20-0.83], P = 0.01).

CONCLUSIONS

The association between the minor allele of rs5068 and a favorable cardiometabolic phenotype that we previously reported in a U.S. population is now replicated in a Mediterranean population in which the G allele of rs5068 is associated with lower blood pressure, BMI, and prevalence of hypertension and metabolic syndrome. These findings may lead to a diagnostic strategy to assess cardiometabolic risk and lay the foundation for the future development of an ANP or ANP-like therapy for metabolic syndrome.

Ankle-brachial index in relation to the natriuretic peptide system polymorphisms and urinary sodium excretion in Chinese

OBJECTIVE

Recent studies have demonstrated that the natriuretic pepetides induce endothelial regeneration and angiogenesis after vascular injury through the autocrine or paracrine action, and might have an inhibitory effect on atherosclerosis. We therefore systematically investigated single nucleotide polymorphisms (SNPs) in the natriuretic peptide system in relation to ankle-brachial index (ABI) in a Chinese population.

METHODS

The study population was recruited from a mountainous area 500 km south of Shanghai from 2003 to 2009. Using the SNapShot method, we first genotyped 951 subjects enrolled in 2005 for 16 SNPs and then the remaining 1355 subjects as validation for 5 SNPs selected from the primary study. ABI and plasma proBNP were measured using the Omron VP-2000/1000 device and the Elecsys proBNP immunoassay, respectively.

RESULTS

Overall, the genetic associations were not significant (P ≥ 0.07). However, in the primary study, there was significant (Pint ≤ 0.045) interaction between 3 SNPs (rs6668352, rs198388, and rs198389) at the NPPA-NPPB locus and urinary sodium excretion in relation to ABI, and the rs6668352 polymorphism had the strongest association (Pint = 0.018). In the primary combined with the validation study populations, the interaction between the rs6668352 polymorphism and urinary sodium excretion in relation to ABI remained statistically significant (Pint = 0.0036). After adjustment for covariates, the rs6668352 A allele carriers, compared with GG homozygotes, had a higher ABI (mean ± standard error, 1.103 ± 0.006 vs. 1.084 ± 0.004, P = 0.009) and lower risk of peripheral arterial disease (PAD, defined as an ABI < 0.90, odds ratio 0.37, 95% confidence interval: 0.14-0.98, P = 0.04) in the subjects of high sodium intake.

CONCLUSION

The minor alleles of 3 SNPs at the NPPA-NPPB locus are associated with a lower risk of PAD, especially in the subjects of high sodium intake.