ACE serum level and I/D gene polymorphism in children with obstructive uropathies and other congenital anomalies of the kidney and urinary tract

Increasing angiotensin-converting enzyme concentrations and absent angiotensin-converting enzyme activity are associated with adverse kidney outcomes in pediatric septic shock

BACKGROUND

Sepsis-induced endothelial dysfunction is proposed to cause angiotensin-converting enzyme (ACE) dysfunction and renin-angiotensin-aldosterone system (RAAS) derangement, exacerbating vasodilatory shock and acute kidney injury (AKI). Few studies test this hypothesis directly, including none in children. We measured serum ACE concentrations and activity, and assessed their association with adverse kidney outcomes in pediatric septic shock.

METHODS

A pilot study of 72 subjects aged 1 week-18 years from an existing multicenter, observational study. Serum ACE concentrations and activity were measured on Day 1; renin + prorenin concentrations were available from a previous study. The associations between individual RAAS components and a composite outcome (Day 1-7 severe persistent AKI, kidney replacement therapy use, or mortality) were assessed.

RESULTS

50/72 subjects (69%) had undetectable ACE activity (< 2.41 U/L) on Day 1 and 27/72 (38%) developed the composite outcome. Subjects with undetectable ACE activity had higher Day 1 renin + prorenin compared to those with activity (4533 vs. 2227 pg/ml, p = 0.017); ACE concentrations were no different between groups. Children with the composite outcome more commonly had undetectable ACE activity (85% vs. 65%, p = 0.025), and had higher Day 1 renin + prorenin (16,774 pg/ml vs. 3037 pg/ml, p < 0.001) and ACE concentrations (149 vs. 96 pg/ml, p = 0.019). On multivariable regression, increasing ACE concentrations (aOR 1.01, 95%CI 1.002-1.03, p = 0.015) and undetectable ACE activity (aOR 6.6, 95%CI 1.2-36.1, p = 0.031) retained associations with the composite outcome.

CONCLUSIONS

ACE activity is diminished in pediatric septic shock, appears uncoupled from ACE concentrations, and is associated with adverse kidney outcomes. Further study is needed to validate these findings in larger cohorts.

Evaluation of insertion/deletion (I/D) polymorphisms of ACE gene and circulating levels of angiotensin II in congenital anomalies of the kidney and urinary tract

BACKGROUND

Congenital Anomalies of the Kidney and the Urinary Tract (CAKUT) are defined as a heterogeneous group of anomalies that resulted from defects in kidney and urinary tract embryogenesis. CAKUT have a complex etiology. Genetic, epigenetic and environmental factors have been investigated in this context. Angiotensin II is a potent vasoconstrictor and exerts an important role in kidney embryogenesis. The angiotensin-converting enzyme (ACE) converts Angiotensin I into Angiotensin II (Ang II) and ACE gene has insertion/deletion (I/D) polymorphisms that have been evaluated in several nephropathies. This study aimed to evaluate whether the I/D polymorphisms of ACE gene and the circulating levels of Ang II are associated with any CAKUT phenotype or CAKUT in general.

METHODS AND RESULTS

Our study was performed with 225 pediatric patients diagnosed with CAKUT and 210 age-and-sex matched healthy controls. ACE I/D alleles were analysed by real-time polymerase chain reaction (RT-PCR). The distribution of ACE I/D polymorphisms were compared between CAKUT patients and healthy controls, as well between ureteropelvic junction obstruction (UPJO), vesicoureteral reflux (VUR), multicystic dysplastic kidney (MCDK) phenotypes and control group. No statistical association was detected between ACE I/D polymorphism and CAKUT and UPJO, VUR, and MCDK phenotypes. In a subset of 80 CAKUT patients and 80 controls, plasma levels of Ang II were measured. No significant differences were found between CAKUT patients and controls, even in regard to comparisons of UPJO, VUR and MCDK with control group.

CONCLUSION

Although CAKUT is a complex disease and the ACE gene may exert a role in kidney embryogenesis, CAKUT was not associated with any ACE I/D polymorphisms nor with differences in plasma levels of Ang II in this Brazilian pediatric population.

Distribution of the ACE1 D Allele in the Bosnian-Herzegovinian Population and its Possible Role in the Regional Epidemiological Picture of COVID-19

Background: The human angiotensin I converting enzyme 1 (ACE1) gene insertion/deletion (I/D) polymorphism is classified based on the presence or absence of a 287 bp Alu sequence. The ACE1 D allele is associated with higher ACE1 concentrations in tissues. Previous research has shown that susceptibility to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is primarily determined by the affinity between the viral receptor-binding domain and the host human receptor angiotensin-converting enzyme 2 (hACE2) receptor. In the human genome, ACE2 is identified as a homolog to ACE1. Objective: The purpose of this study was to characterize the ACE1 D allele distribution in Bosnia and Herzegovina (B&H), so as to compare it to population data from other European countries and to investigate the potential correlation between D allele frequencies and coronavirus disease 2019 (COVID-19) epidemiological findings in selected European populations. Methods: The ACE1 D allele frequencies in 18 selected European populations were analyzed and compared with COVID-19 prevalence, mortality, and severity using multivariate linear regression analysis. Results and Discussion: The ACE1 D allele distribution within the B&H population was similar to its distribution in other European populations. Regression analysis showed no significant correlation between the D allele frequency and the incidence of infections between the examined populations, nor with the rates of fatality and severe cases. Conclusion: There is no clear statistical evidence that the ACE1 D allele is associated with increased or decreased COVID-19 incidence, mortality, and case severity within the investigated populations.

Understanding COVID-19: A hypothesis regarding digit ratio (2D:4D), ACE I/D polymorphism, oxygen metabolism and national case fatality rates

OBJECTIVE

Male digit ratio (2D:4D) correlates positively with the national case fatality rate (CFR) for COVID-19. The severity of COVID-19 may be influenced by a counterbalance between the angiotensin-converting enzyme (ACE) and angiotensin-converting enzyme 2 (ACE2). SARS-CoV2 cleaves with ACE2 and enters cells leaving an unopposed effect of ACE in the lungs. Both 2D:4D and the ACE I/D polymorphism are covariates of oxygen metabolism. COVID-19 leads to lung damage and a reduction in oxygen saturation of the blood. Here, we examine the interrelationships between 2D:4D, ACE polymorphism, and COVID-19 CFR.

METHODS

National frequencies/rates were obtained for 2D:4D from the BBC Internet study (n = 41), published values of ACE I/II (n = 39), and COVID-19 CFR from three World Health Organization situation reports (n = 41).

RESULTS

2D:4D was negatively associated with national ACE I/II frequencies. However, there was a positive relationship between male 2D:4D and CFR (right and left 2D:4D, two, and three situation reports respectively). The relationships between ACE I/II and CFR were non-significant. Relationships between male 2D:4D and CFR's were independent of female 2D:4D and ACE I/II.

CONCLUSIONS

The ACE I/D polymorphism may influence 2D:4D such that ACE II individuals have lower 2D:4D than ACE DD individuals. Low 2D:4D and ACE II individuals show efficient oxygen metabolism. Therefore, low 2D:4D and ACE II together may protect against COVID-19 severity. The sex-dependent positive correlation between male 2D:4D and CFR is independent of ACE I/II, suggesting that the sex-dependent variation in the ACE2 gene may also influence the 2D:4D phenotype.

ACE deletion allele is associated with susceptibility to SARS-CoV-2 infection and mortality rate: An epidemiological study in the Asian population

•

Differential distribution of ACE I/D polymorphism observed in Asian countries.

•

Allele D of ACE I/D polymorphism was associated with susceptibility to SARS-CoV-2 infection.

•

The minor allele of ACE I/D was linked with COVID-19 mortality in the Asian population.

Background

Severe acute respiratory syndrome corona virus-2 (SARS-CoV-2) is believed to have emerged from Wuhan, China, and spreads over 215 countries worldwide. The spike protein of SARS-CoV-2 binds to angiotensin-converting enzyme-2 (ACE-2) receptors and enter the host cells. Several reports have been highlighted the importance of ACE-2 on the pathogenesis of COVID-19. In the present study, we hypothesize that a functional insertion/deletion polymorphism in the ACE gene could be associated with SARS-CoV-2 infection and mortality.

Materials and methods

PubMed and Google scholar search engines were used to obtained data on the prevalence of ACE I/D polymorphism in different countries of the Asia continent. Data on COVID-19 infection rate (per million), mortality/million, and percentage of recovery were acquired form worldometer website. The Spearman rank correlation test performed to investigate the correlation of allele ‘D’ with SARS-CoV-2 infection, mortality rate, and recovery percentage.

Results

Epidemiological investigation revealed a significant positive correlation of D allele of ACE polymorphism with SARS-CoV-2 infection (r = 0.502, p = 0.008, n = 26) and mortality rate (r = 0.620, p = 0.002, n = 22) in Asian population. However, no significant role of ACE I/D polymorphism was observed with recovery rate of patients from SARS-CoV-2 infection (r = −0.208, p = 0.352, n = 22).

Conclusions

Allele D of ACE insertion/deletion polymorphism is associated with the rate of infection and mortality in the Asian population.

The Gene Polymorphism of Angiotensin-Converting Enzyme Intron Deletion and Angiotensin-Converting Enzyme G2350A in Patients With Left Ventricular Hypertrophy: A Meta-analysis

Objectives

The aim of the study was to evaluate the correlation between left ventricular hypertrophy and the gene polymorphism of angiotensin-converting enzyme (ACE) intron deletion (I/D) and ACE G2350A.

Methods

Information related to the sample size and genotype frequencies was extracted from each study.

Results

Our results found that the D allele (p = 0.0180) and DD genotype (p = 0.0110) of ACE I/D had a significant association with increasing the risk of left ventricular hypertrophy, whereas the I allele (p = 0.0180), but not II (p = 0.1660) and ID genotypes (p = 0.1430), was associated with decreasing the risk of left ventricular hypertrophy. On other hand, we found that the A allele (p = 0.0020) and GA genotype of ACE G2350A (p = 0.0070) had the correlation with increasing the risk of left ventricular hypertrophy.

Conclusions

Our meta-analysis reveals that the D allele of ACE I/D and the A allele of ACE G2350A are associated with increasing the risk of left ventricular hypertrophy.

Serum and Urinary NGAL and Cystatin C Levels as Diagnostic Tools for Acute Kidney Injury and Chronic Kidney Disease: A Histobiochemical Comparative Study

BACKGROUND

High global incidence of acute kidney injury (AKI) is an observable complication in critically ill patients. Long-term disease and medication complexity contribute to devastating chronic kidney disease (CKD), diminishing quality of life.

OBJECTIVES

To establish new biomarkers to guide patient care and facilitate novel therapeutics development.

METHODS

Serum and urinary levels of creatinine, CysC, and NGAL were estimated in 86 renal patients and compared with healthy controls for AKI and CKD categorization. Creatinine and CysC measurements were used to estimate GFR. Kidney biopsies were prepared for light microscopy for further characterization. Patients' demographic data were used in group association studies.

RESULTS

Thirty-six patients met the criteria for AKI and 50 for CKD. Both mean serum and urine creatinine levels were significantly elevated by 2.8 and 2.6, respectively, from baseline in 48 h in the AKI group but not CKD group. Mean serum Cystatin C (CysC) values were higher than controls but similar in both disease states, while urine levels were slightly higher in CKD patients, and remained steady by the end of the follow-up (EF-Up). Further, a significant 2.9-fold and 5.5-fold (p=0.001) increase in serum NGAL in AKI and CKD, respectively, and a dramatic 7.1-factor reduction in AKI group, but no appreciable change in the CKD group from admission to EF-Up were observed. Similarly, urine NGAL level for AKI and CKD increased 3.2-fold and 6-fold respectively, on admission, which decreased moderately with the AKI group (2.5-fold) but increased by a factor of 1-8 (10.7- fold; p=0.001) at EF-Up. ROC assessment curve revealed relatively higher NGAL performance at good predictive values than CysC (p < 0.009).

CONCLUSION

Our data demonstrated creatinine elevation by a factor > 2 in 48 h in AKI group but not CKD group, which returned close to normal levels by the EF-Up, an indication of abrupt renal injury in AKI, compared with a persistent effect in the CKD group. Both serum and urine NGAL sensitivity and specificity provided powerful discriminative tool between AKI and CKD by reduction in the AKI group and an increase in the CKD group by the EF-UP, thus, contributing in establishing the basis for AKI and CKD classification. CysC, however, displayed less sensitivity than NGAL, indicating effects by enigmatic non-specific factors.