Association of the genetic polymorphisms of the ACE gene and the eNOS gene with lupus nephropathy in northern Chinese population

A Novel Network Pharmacology Strategy to Decode Mechanism of Lang Chuang Wan in Treating Systemic Lupus Erythematosus

Complex disease is a cascade process which is associated with functional abnormalities in multiple proteins and protein-protein interaction (PPI) networks. One drug one target has not been able to perfectly intervene complex diseases. Increasing evidences show that Chinese herb formula usually treats complex diseases in the form of multi-components and multi-targets. The key step to elucidate the underlying mechanism of formula in traditional Chinese medicine (TCM) is to optimize and capture the important components in the formula. At present, there are several formula optimization models based on network pharmacology has been proposed. Most of these models focus on the 2D/3D similarity of chemical structure of drug components and ignore the functional optimization space based on relationship between pathogenetic genes and drug targets. How to select the key group of effective components (KGEC) from the formula of TCM based on the optimal space which link pathogenic genes and drug targets is a bottleneck problem in network pharmacology. To address this issue, we designed a novel network pharmacological model, which takes Lang Chuang Wan (LCW) treatment of systemic lupus erythematosus (SLE) as the case. We used the weighted gene regulatory network and active components targets network to construct disease-targets-components network, after filtering through the network attribute degree, the optimization space and effective proteins were obtained. And then the KGEC was selected by using contribution index (CI) model based on knapsack algorithm. The results show that the enriched pathways of effective proteins we selected can cover 96% of the pathogenetic genes enriched pathways. After reverse analysis of effective proteins and optimization with CI index model, KGEC with 82 components were obtained, and 105 enriched pathways of KGEC targets were consistent with enriched pathways of pathogenic genes (80.15%). Finally, the key components in KGEC of LCW were evaluated by in vitro experiments. These results indicate that the proposed model with good accuracy in screening the KGEC in the formula of TCM, which provides reference for the optimization and mechanism analysis of the formula in TCM.

Upregulation of Proinflammatory Bradykinin Peptides in Systemic Lupus Erythematosus and Rheumatoid Arthritis

Our recent study has implicated bradykinin (BK) signaling as being of pathogenic importance in lupus. This study aims to investigate the biomarker potential of BK peptides, BK and BK-des-arg-9, in lupus and other rheumatic autoimmune diseases. Sera from systemic lupus erythematosus (SLE) patients and healthy subjects were screened for BK and BK-des-arg-9 by liquid chromatography-mass spectrometry metabolomics. Serum from 6-mo-old C57BL/6 mice and three murine lupus strains were also screened for the two peptides by metabolomics. Given the promising initial screening results, validation of these two peptides was next conducted using multiple reaction monitoring in larger patient cohorts. In initial metabolomics screening, BK-des-arg-9 was 22-fold higher in SLE serum and 106-fold higher in mouse lupus serum compared with healthy controls. In validation assays using multiple reaction monitoring and quadrupole time-of-flight mass spectrometry, BK and BK-des-arg-9 showed significant elevations in SLE serum compared with controls (p < 0.0001; area under the curve = 0.79-0.88), with a similar but less pronounced increase being noted in rheumatoid arthritis serum. Interestingly, increased renal SLE disease activity index in lupus patients was associated with reduced circulating BK-des-arg-9, and the reasons for this remain to be explored. To sum, increased conversion of BK to the proinflammatory metabolite BK-des-arg-9 appears to be a common theme in systemic rheumatic diseases. Besides serving as an early marker for systemic autoimmunity, independent studies also show that this metabolic axis may also be a pathogenic driver and therapeutic target in lupus.

The Endothelial Nitric Oxide Synthase Gene Polymorphism is Associated with the Susceptibility to Immunoglobulin a Nephropathy in Chinese Population

BACKGROUND/AIMS

Endothelial nitric oxide synthase (eNOS) is one of the most important enzymes for producting nitric oxide (NO), which regulate the function of many organs and cells. The single nucleotide polymorphisms (SNPs) of eNOS were found to be associated with many kidney diseases. However, it is lack of relevant studies to evaluate the associations between eNOS polymorphisms and immunoglobulin A nephropathy (IgAN). This case-control study aimed to evaluate the relationship between eNOS polymorphisms and IgAN.

METHODS

We recruited 351 IgAN patients and 310 age- and sex-matched healthy controls from Northwest China. Sequenom MassARRAY was used to detect the genotypes of two common eNOS SNPs (rs1799983 and rs2070744). Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated by the Chi square test to evaluate the associations between eNOS and IgAN. Phase 2.1 was used to conduct haplotype analysis.

RESULTS

In the overall analysis, we found that the rs1799983 polymorphism was associated with a decreased risk of IgAN (G/T vs. G/G: OR=0.57, 95%CI=0.34-0.96; G/T+T/T vs. G/G: OR=0.52, 95%CI=0.31-0.86; G/T vs.

G/G-T/T

OR=0.60, 95%CI=0.36-0.99; Log-additive model: OR=0.48, 95%CI=0.30-0.78). Haplotype analysis indicated that Trs1799983Crs2070744 is a protective factor against IgAN (OR=0.62, 95%CI=0.42--0.92). However, no significant differences were found between the two SNPs (rs1799983 and rs2070744) and clinical features (age, sex, blood pressure, and Lee's grade) of IgAN.

CONCLUSION

The eNOS gene rs1799983 polymorphism and Trs1799983Crs2070744 haplotype may reduce the risk of IgAN in Chinese populations.

Angiotensin-converting enzyme insertion/deletion gene polymorphism in Egyptian children with systemic lupus erythematosus: a possible relation to proliferative nephritis

Introduction Angiotensin-converting enzyme (ACE) is crucial in the pathogenesis of systemic lupus erythematosus through angiotensin II which regulates vascular tone and endothelial functions. Objectives To study the frequency of ACE insertion/deletion (I/D) gene polymorphism in Egyptian children with systemic lupus erythematosus and its possible relation to the renal pathology in cases with lupus nephritis. Subjects and methods The frequency of ACE gene insertion/deletion polymorphism genotypes was determined in 78 Egyptian children with systemic lupus erythematosus and compared to a matched group of 140 healthy controls using polymerase chain reaction. Results The DD genotype of the ACE gene was higher in systemic lupus erythematosus patients when compared to controls ( P<0.0001; odds ratio (OR) 2.4; 95% confidence interval (CI) 1.7-3.3) and the D allele was more frequent than the I allele in systemic lupus erythematosus patients in comparison to controls ( P < 0.0001; OR = 2.2; 95% CI = (1.6-3.1). In the lupus nephritis group, the DD genotype was significantly higher in those with proliferative lupus nephritis when compared to those with non-proliferative lupus nephritis ( P = 0.02; OR = 1.45; 95% CI = 1.4-1.6). Also, patients with proliferative lupus nephritis showed a higher frequency of the D allele ( P < 0.001; OR = 1.98; 95% CI = 1.3-2.9). Conclusion The D allele and DD genotype of the ACE gene appear to be a risk factor for the susceptibility of systemic lupus erythematosus and occurrence of proliferative nephritis in Egyptian children.

Association of angiotensin-converting enzyme gene polymorphisms with Crohn's disease in a Chinese Han population

OBJECTIVE

To investigate whether Angiotensin-converting enzyme (ACE) gene polymorphisms alter the susceptibility of a Chinese Han population to Crohn's disease (CD).

METHODS

Blood samples were collected from patients with CD and from healthy control subjects for analyzing SNP rs4291 (promoter, A262T), SNP rs4343 (exon 16, A11860G), and rs4646994 (intron 16, Alu insertion/deletion). Allele and genotype frequencies were compared, and pairwise linkage disequilibrium and haplotypes were analyzed in patients with CD.

RESULTS

Both rs4343 A/G and rs4646994 I/D allele frequencies differed significantly between patients with CD and control subjects (rs4343: OR=1.438, 95% CI=1.099-1.882, P=0.008; rs4646994: OR=1.559, 95% CI=1.191-2.039, P=0.001). There were also significant associations between the risk of CD and both rs4343 AA/(AG+GG) and rs4646994 II/(ID+DD) genotype frequencies (P=0.039 and P=0.019). The frequency of the G-D haplotype was significantly lower in patients with CD than control subjects (31.7% vs. 40.4%, P=0.010).

CONCLUSIONS

The results suggest that ACE rs4343G and rs4646994D alleles protect against CD, while rs4343AA and the I allele in the dominant genetic model are risk alleles for CD. The association between the G-D haplotype and CD was significant, suggesting a protective role in the pathogenesis of CD.

Association of eNOS gene polymorphisms and systemic lupus erythematosus in southeast Iran

BACKGROUND AND OBJECTIVES

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with unknown etiology. Genetic and environmental factors play important roles in the pathogenesis of SLE. The primary objective of this study was to investigate the possible association of eNOS gene intron 4b/a, Glu298Asp and T-786C polymorphisms with SLE in southeast Iran populations.

PATIENTS AND METHODS

This was a case-control study comparing eNOS polymorphisms in 106 SLE patients and 196 age- and sex-matched healthy controls. The 4b/a, Glu298Asp and T-786C polymorphisms were analyzed using polymerase chain reaction and restriction fragment length polymorphism.

RESULTS

Our findings indicated that the 4b/a polymorphism was associated with SLE, and the risk of SLE was 3.5- and 1.75-fold higher in patients with aa and ba genotypes than in patients with bb genotype. No association was observed between Glu298Asp and T-786C polymorphisms and SLE. There were no differences in eNOS gene polymorphisms between the Balouch and Fars population.

CONCLUSION

Statistically significant differences were observed in genotypes and allele frequencies of 4b/a polymorphism between patients with SLE and healthy controls in southeast Iran.

Association between genetic polymorphisms of ACE & eNOS and diabetic nephropathy

Diabetic nephropathy (DN) is the leading cause of end-stage renal disease, with multiple genetic and environmental factors involving in its etiology. ACE and eNOS gene were considered to have important roles in the development and progression of DN. In this study, a case-control study was carried out to investigate the effects of 7 SNPs in ACE gene and 2 SNPs in eNOS gene in the development of DN in Northern China.7 SNPs including A240T, A2350G, A5466C, A2215G, T3892C, C1237T and C3409T of ACE gene and 2 SNPs (G894T and T786C) of eNOS gene were genotyped by polymerase chain reaction restriction fragment length polymorphism method. 431 type 2 diabetic patients with nephropathy (cases) were compared to 420 type 2 diabetic patients without nephropathy (controls) in the study. Data were analyzed by SPSS 17.0 and HaploView software. The frequency distribution of A2350G, 4 haplotyps in ACE gene and G894T in eNOS gene were demonstrated to be different between case and control groups significantly. Whereas other SNPs and haplotypes had no differences in two cohorts. The results revealed that variations of ACE and eNOS gene had association with DN, which indicated ACE and eNOS gene may play an important role in pathogenesis of DN in Northern Chinese Han population.

Relationship between angiotensin-converting enzyme insertion/deletion gene polymorphism and systemic lupus erythematosus/lupus nephritis: a systematic review and metaanalysis

OBJECTIVE

Results from studies of the association between angiotensin-converting enzyme (ACE) insertion/deletion (I/D) gene polymorphism and systemic lupus erythematosus (SLE)/lupus nephritis (LN) are controversial. We performed this metaanalysis to evaluate the relationship between ACE I/D gene polymorphism and SLE/LN and to explore whether the ACE D allele or DD genotype could become a predictive marker for risk of SLE/LN.

METHODS

Association studies were identified from the databases of PubMed, Embase, Cochrane Library and CBM-disc (China Biological Medicine Database) as of May 1, 2011, and eligible investigations were synthesized using a metaanalysis method. Results were expressed with OR for dichotomous data, and 95% CI were calculated.

RESULTS

Sixteen investigations were identified for the analysis of association between ACE I/D gene polymorphism and SLE, consisting of 1959 patients with SLE and 2078 controls. In the overall populations, there was a marked association between D allele or DD genotype and SLE susceptibility (D: OR 1.29, 95% CI 1.04-1.58, p = 0.02; DD: OR 1.60, 95% CI 1.17-2.19, p = 0.003), and DD homozygous was associated with LN risk (OR 2.78, 95% CI 1.26-6.11, p = 0.01). In the subgroup analysis, DD genotype associated with SLE risk was observed in Asians; no other association was found in Asians, whites, Africans, and Brazilians.

CONCLUSION

D allele and DD homozygous are significant genetic molecular markers to predict SLE susceptibility, and DD genotype is a valuable marker to predict the LN risk. More investigations are required to clarify the association of the D allele or DD homozygous with SLE/LN susceptibility.

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.