Angiotensin converting enzyme gene polymorphism in Indian children with steroid sensitive nephrotic syndrome

SARS-CoV-2 infections and COVID-19 mortalities strongly correlate with ACE1 I/D genotype

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COVID-19 infection is characterized by its prominent effect on specific ethnic group.

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SARS-CoV-2 cases/mortality were negatively associated with ACE1 II genotype.

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The ACE1 II genotype could be a predictive marker of SARS-CoV-2 risk and severity.

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19). The relentless spread and pathogenicity of the virus have become a global public health emergency. One of the striking features of this pandemic is the pronounced impact on specific regions and ethnic groups. In particular, compared with East Asia, where the virus first emerged, SARS-CoV-2 has caused high rates of morbidity and mortality in Europe. This has not been experienced in past global viral infections, such as influenza, severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) and is unique to SARS-CoV-2. For this reason, we investigated the involvement of genetic factors associated with SARS-CoV-2 infection with a focus on angiotensin-converting enzyme (ACE)-related genes, because ACE2 is a receptor for SARS-CoV-2. We found that the ACE1 II genotype frequency in a population was significantly negatively correlated with the number of SARS-CoV-2 cases. Similarly, the ACE1 II genotype was negatively correlated with the number of deaths due to SARS-CoV-2 infection. These data suggest that the ACE1 II genotype may influence the prevalence and clinical outcome of COVID-19 and serve as a predictive marker for COVID-19 risk and severity.

Effect of angiotensin converting enzyme gene I/D polymorphism in South Indian children with nephrotic syndrome

Nephrotic syndrome is one of the most common childhood kidney diseases. It is mostly found in the age group of 2 to 8 years. Around 10%–15% of nephrotic syndrome cases are non-responders of steroid treatment (SRNS). Angiotensin converting enzyme (ACE) (I/D) gene association studies are important for detecting kidney disease and herein we assessed the association of ACE (I/D) polymorphism with nephrotic syndrome in South Indian children. We recruited 260 nephrotic syndrome (162 boys and 98 girls) and 218 (140 boys and 78 girls) control subjects. ACE I/D polymorphism was analyzed by PCR using genotype allele specific primers. In ACE (I/D), we did not find significant association for the ungrouped data of nephrotic syndrome children and the control subjects. Kidney biopsies were done in 86 nephrotic syndrome cases (minimal change disease, n=51; focal segmental glomerulosclerosis, n=27; diffuse mesangial proliferation, n=8). We segregated them into the minimal change disease / focal segmental glomerulosclerosis groups and observed that the ACE ‘D’ allele was identified with borderline significance in cases of focal segmental glomerulosclerosis and the ‘I’ allele was assessed as having very weak association in cases of minimal change disease. ‘II’ genotype was weakly associated with minimal change disease. Gender specific analysis revealed weak association of ‘ID’ genotype with female nephrotic syndrome in females. Dominant expression of DD genotype was observed in males with nephrotic syndrome. Our finding indicated that ACE (I/D) has moderate association with focal segmental glomerulosclerosis. However, due to the limited number of biopsy proven focal segmental glomerulosclerosis subjects enrolled, further studies are required to confirm these results.

Genetic and in vivo determinants of glucocorticoid sensitivity in relation to clinical outcome of childhood nephrotic syndrome

Following initial glucocorticoid treatment, the clinical course in children with nephrotic syndrome is highly variable. Intrinsic sensitivity to glucocorticoids might be a determinant of this variability. Functional polymorphisms of the glucocorticoid receptor gene NR3C1 have been associated with either relatively impaired (GR-9β) or increased (BclI) glucocorticoid sensitivity. Here, in a prospective, well-defined cohort of children with nephrotic syndrome, we evaluated both carriage of GR-9β+TthIII-1 and BclI haplotypes in 113 children and a dexamethasone suppression test in 90 children in relation to their clinical outcome over a median follow-up of 4.4 years. Carriers of GR-9β+TthIII-1 had a significantly higher incidence of steroid dependence 13/25 (52%) compared with noncarriers 19/75 (25%) with a hazard ratio adjusted for gender, age, and descent of 3.04 with 95% confidence interval 1.37-6.74. Both first and frequent relapses happened significantly more often in GR-9β+TthIII-1 carriers than in noncarriers. There were no significant differences in therapeutic outcomes between carriers and noncarriers of the BclI haplotype. Results of the dexamethasone test showed no associations with clinical outcome. Thus, the GR-9β+TthIII-1 haplotype of the glucocorticoid receptor gene offers new insights into the clinical course of children with nephrotic syndrome.

Evaluation of paraoxonase activity in children with nephrotic syndrome

Background

It has been proposed that reactive oxygen species (ROS) is involved in the pathogenesis of various diseases. Paraoxonase, a high-density lipoprotein associated enzyme, prevents low-density lipoproteins from oxidation.

Objectives

The aim of the present study was to investigate the serum activities of paraoxonase-1 (PON-1), and aryleterase (ARE) as well as total antioxidant capacity (TAC) in children with nephrotic syndrome in acute and remission phase.

Patients and Methods

The study consisted of 20 patients in acute and remission phases and 23 healthy controls. PON-1 and ARE activities were determined spectrophotometrically using paraoxone and phenyacetate as substrate, respectively. TAC was measured using ferric reducing ability of plasma (FRAP).

Results

The levels of PON, ARE, and TAC were significantly lower in acute phase of nephrotic syndrome compared with the remission phase. The levels of PON, ARE and TAC increased in remission phase.

Conclusions

Our results revealed that the determination of paraoxonase activity might be a biomarker for responses to nephrotic syndrome treatment, which needs to be fully clarified.

Association of the ACE-II genotype with the risk of nephrotic syndrome in Pakistani children

Nephrotic syndrome is a common pediatric glomerular disease associated with heavy proteinuria. Since, the angiotensin converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism is a putative genetic risk factor for NS, in this study, ACE (I/D) polymorphism was analyzed in 268 NS and 223 control samples by a PCR-based method. The genotypic and allelic frequencies were determined and the association between ACE I/D polymorphism and NS was evaluated. The frequency distribution of the II, ID and DD genotypes was 82 (30.6%), 128 (47.8%) and 58 (21.6%) in the NS patients and 9 (4.0%), 171 (76.7%) and 43 (19.3%) in the control samples respectively. In the Pakistani pediatric NS population, the II genotypic and allelic frequencies were found to be significantly associated with the disease (OR=6.755; C.I=3-14.9). No significant association was found between this polymorphism and the response to standard steroid therapy. Thus, in contrast to reports from other parts of the world, the II genotype was found to be significantly associated with NS in the Indian and Malay populations and in the Pakistani population described here. To our knowledge, this is the first report from Pakistan describing the association of the ACE I/D polymorphism with pediatric NS. On the basis of these results, it is suggested that analysis of the ACE (I/D) polymorphism should be performed for the early diagnosis in the high risk NS patients in South Asia.

A meta-analysis of the association between angiotensin-converting enzyme insertion/deletion gene polymorphism and steroid-sensitive nephrotic syndrome in children

BACKGROUND AND OBJECTIVE

Angiotensin-converting enzyme (ACE) insertion/deletion (I/D) gene polymorphism correlates with circulating and cellular ACE concentration. Association between ACE I/D gene polymorphism and steroid-sensitive nephrotic syndrome (SSNS) risk in children is still controversial. This meta-analysis was performed to evaluate the relation between ACE I/D gene polymorphism and SSNS susceptibility in children.

METHODS

The relevant investigations were screened from the search engines of PubMed, Cochrane Library and CBM-disc (China Biological Medicine Database) as of 1 March 2011, and eligible studies were synthesized using meta-analysis methods.

RESULTS

Ten studies were identified for the analysis of association between ACE I/D gene polymorphism and SSNS risk in children, including seven in Asians, one for Caucasians and two in Africans. There was no markedly positive association between D allele or DD genotype and SSNS susceptibility in Asians, Caucasians and Africans (D: Asians OR = 1.24, p = 0.28; Caucasians OR = 1.61, p = 0.15; Africans OR = 1.61, p = 0.53; DD: Asians OR = 1.72, p = 0.15; Caucasians OR = 1.39, p = 0.48; Africans OR = 1.80, p = 0.56). Furthermore, II homozygous seemed not to play a protective role against SSNS onset for Asians, Caucasians and Africans (Asians OR = 0.95, p = 0.85; Caucasians OR = 0.30, p = 0.11; Africans OR = 0.60, p = 0.65).

CONCLUSIONS

There was no association between ACE I/D gene polymorphism and SSNS susceptibility in Asians, Caucasians and Africans. However, the conclusions for Caucasians and Africans were less powerful.

Association of angiotensin converting enzyme insertion/deletion gene polymorphism with idiopathic nephrotic syndrome susceptibility in children: a meta-analysis

Background and objective: Angiotensin converting enzyme (ACE) gene contains either an insertion (I) allele or a deletion (D) allele forming three potential genotypes: II, ID and DD. The D allele or DD genotype has been reported to be associated with higher plasma ACE level. An assessment of the association between ACE I/D gene polymorphism and idiopathic nephrotic syndrome (INS) susceptibility in children is still controversial. This meta-analysis was performed to evaluate the association between ACE I/D gene polymorphism and the onset of INS.

Method: A predefined literature search and selection of eligible relevant studies were performed to collect data from electronic databases, and eligible investigations were synthesized using the meta-analysis method.

Results: Nine investigations were identified for the analysis of association between ACE I/D gene polymorphism and INS risk in children, including six in Asians, one study for Caucasians and two for Africans. There was positive association between D allele or DD genotype and INS susceptibility in Asians (OR = 1.75, p = 0.01; OR = 2.01, p = 0.02), but not for Caucasian children and Africans (for Caucasians, D: OR=1.35, p = 0.27, DD: OR = 0.95, p = 0.91; for Africans, D: OR = 1.70, p = 0.56, DD: OR = 1.60, p = 0.73). Furthermore, II homozygous seemed to play a positive role against INS onset for Asians (OR = 0.59, p = 0.02), but the link between II genotype and INS risk was not observed in Caucasian children and Africans (Caucasians: OR = 0.31, p = 0.06; Africans: OR = 0.50, p = 0.59).

Conclusions: D allele and DD homozygous might become significant genetic molecular markers for INS susceptibility in Asian children, but the association was not observed in Caucasians or Africans. However, the conclusion from our study cannot be sustained and more investigations on larger sample in different populations are required to further clarify the role of D allele or DD homozygous in the onset of INS in difference races.

ACE I/D gene polymorphism can't predict the steroid responsiveness in Asian children with idiopathic nephrotic syndrome: a meta-analysis

Background

The results from the published studies on the association between angiotensin-converting enzyme (ACE) insertion/deletion (I/D) gene polymorphism and the treatment response to steroid in Asian children with idiopathic nephrotic syndrome (INS) is still conflicting. This meta-analysis was performed to evaluate the relation between ACE I/D gene polymorphism and treatment response to steroid in Asian children and to explore whether ACE D allele or DD genotype could become a predictive marker for steroid responsiveness.

Methodology/Principal Findings

Association studies were identified from the databases of PubMed, Embase, Cochrane Library and CBM-disc (China Biological Medicine Database) as of September 1, 2010, and eligible investigations were synthesized using meta-analysis method. Five investigations were identified for the analysis of association between ACE I/D gene polymorphism and steroid-resistant nephrotic syndrome (SRNS) risk in Asian children and seven studies were included to explore the relationship between ACE I/D gene polymorphism and steroid-sensitive nephrotic syndrome (SSNS) susceptibility. Five investigations were recruited to explore the difference of ACE I/D gene distribution between SRNS and SSNS. There was no a markedly association between D allele or DD genotype and SRNS susceptibility or SSNS risk, and the gene distribution differences of ACE between SRNS and SSNS were not statistically significant. II genotype might play a positive role against SRNS onset but not for SSNS (OR = 0.51, P = 0.02; OR = 0.95, P = 0.85; respectively), however, the result for the association of II genotype with SRNS risk was not stable.

Conclusions/Significance

Our results indicate that D allele or DD homozygous can't become a significant genetic molecular marker to predict the treatment response to steroid in Asian children with INS.

Possible role of angiotensin-converting enzyme polymorphism on progression of hepatic fibrosis in chronic hepatitis C virus infection

Many functional polymorphisms in the rennin-angiotensin system (RAS) have been described; these polymorphisms have been postulated to contribute to fibrosis in several diseases. Our aim was to study the frequency of ACE I/D polymorphism in chronic hepatitis C virus (HCV) infection and its association with liver fibrosis and response to treatment. This study included 90 patients with chronic hepatitis C. All patients received antiviral therapy in the form of pegylated interferon and ribavirin. Patients were grouped according to the stage of liver fibrosis by biopsy into: group 1 (fibrosis: 0 or 1); group 2 (fibrosis: 2 or 3) and group 3 (fibrosis: 4 or 5). The study included also 170 healthy subjects, as a control group. Polymerase chain reaction was carried out to detect the different ACE genotypes. The D/D genotype was significantly more prevalent among HCV patients compared to controls (65.6% vs 48.2%, P=0.006). Degree of necroinflammation was significantly higher among patients with I/I genotype when compared to patients with D/D genotype (P=0.04). No significant difference in the distribution of the ACE I/D genotypes between the fibrosis groups and between responders and non responders to interferon therapy. The D/D genotype may increase the susceptibility to infection with hepatitis C.

Effect of angiotensin-converting enzyme gene insertion/deletion polymorphism on steroid resistance in Egyptian children with idiopathic nephrotic syndrome

Introduction. The presence of the deletion (D) allele in the angiotensin-converting enzyme (ACE) gene has been reported as a probable genetic risk factor for idiopathic nephrotic syndrome (INS), but its role in determining resistance to steroid therapy remains to be evaluated.

Methods. Fifty-one patients were enrolled in the study and received oral steroids. The pattern of response to steroid therapy was determined. A group of 50 healthy adults served as a control group. The genotypes for ACE insertion (I)/D polymorphism were analysed using a PCR-based method.

Results. Twenty patients were steroid sensitive (SS) and 31 were non-SS. The presence of hypertension at presentation was significantly related to steroid unresponsiveness. Among the SS group, the frequencies of the II, ID, and DD genotypes of the ACE gene were 20% (n=4), 65% (n=13), and 15% (n=3), respectively, while the frequencies among the non-SS group were 19.4% (n=6), 74.2% (n=23), and 6.5% (n=2), respectively. The differences between the two groups were not statistically significant (Chi square=0.59).

Conclusion. The current study on Egyptian children with INS reveals no association between the ACE gene I/D polymorphism and clinical parameters, histological findings, and steroid resistance.

The geographic distribution of the ACE II genotype: a novel finding

Angiotensin converting enzyme (ACE) gene polymorphism insertion (I) or deletion (D) has been widely studied in different populations, and linked to various functional effects and associated with common diseases. The purpose of the present study was to investigate the relationship between the ACE I/D frequency in different populations and geographic location; ACE I/D allele frequency in the Lebanese population and ACE II genotype contribution to the geographic trend were also identified. Five hundred and seventy healthy volunteers were recruited from the Lebanese population. Genomic DNA was extracted from buccal cells, and amplified by polymerase chain reaction; products were then identified by gel electrophoresis. The frequencies of the different ACE I/D genotypes were determined and tested for Hardy-Weinberg equilibrium (HWE). To assess the relationship between ACE I/D frequency and geographic location, and to identify how the Lebanese population contributes to the geographic trend in ACE I/D frequencies, Eurasian population samples and Asians were incorporated in the analyses from the literature. The frequency of the I allele in the Lebanese population was 27% and the corresponding II genotype was at a frequency of 7.37% (in HWE; P=0.979). The ACE I allele and genotype frequencies show an association with longitude, with frequencies increasing eastwards and westwards from the Middle East.