Angiotensin II Type 2 Receptor Antibodies in Glomerular Diseases

We evaluated the concentration of AT2R antibodies in 136 patients with primary and secondary glomerular diseases: membranous nephropathy (n = 18), focal and segmental glomerulosclerosis (n = 25), systemic lupus erythematosus (n = 17), immunoglobulin A (IgA) nephropathy (n = 14), mesangial (non-IgA) proliferative nephropathy (n = 6), c-ANCA vasculitis (n = 40), perinuclear anti-neutrophil cytoplasmic antibodies (p-ANCA) vasculitis (n = 16), and compared it with a healthy control group (22 patients). Serum creatinine levels, proteinuria, serum albumin, and total protein concentrations were prospectively recorded for 2 years. The mean levels of AT2R antibodies in the lupus nephropathy group were significantly higher compared to the control group, 64.12 ± 26.95 units/mL and 9.72 ± 11.88 units/mL, respectively. There was no association between this level and the clinical course of the disease. The AT2R levels in other kinds of glomerular disease were no different from the control group. We found significant correlations between AT1R and AT2R in patients with membranous nephropathy (r = 0.66), IgA nephropathy (r = 0.61), and c-ANCA vasculitis (r = 0.63). Levels of AT2R antibodies in systemic lupus erythematosus are higher compared to other types of glomerulonephritis, vasculitis, and a healthy control group. Levels of AT2R antibodies correlate with AT1R antibodies in the groups of patients with membranous nephropathy, IgA nephropathy, and c-ANCA vasculitis. These kinds of AT2R antibodies have a stimulative effect on AT2R, but we have not found the influence of these antibodies on the clinical course of glomerular diseases.

The Renin-Angiotensin System: The Challenge behind Autoimmune Dermatological Diseases

Autoimmune dermatological diseases (AIDD) encompass a diverse group of disorders characterized by aberrant immune responses targeting the skin and its associated structures. In recent years, emerging evidence suggests a potential involvement of the renin-angiotensin system (RAS) in the pathogenesis and progression of these conditions. RAS is a multicomponent cascade, primarily known for its role in regulating blood pressure and fluid balance. All of the RAS components play an important role in controlling inflammation and other immune responses. Angiotensin II, the main effector, acts on two essential receptors: Angiotensin Receptor 1 and 2 (AT1R and AT2R). A disturbance in the axis can lead to many pathological processes, including autoimmune (AI) diseases. AT1R activation triggers diverse signaling cascades involved in inflammation, fibrosis and tissue remodeling. Experimental studies have demonstrated the presence of AT1R in various cutaneous cells and immune cells, further emphasizing its potential contribution to the AI processes in the skin. Furthermore, recent investigations have highlighted the role of other RAS components, beyond angiotensin-converting enzyme (ACE) and Ang II, that may contribute to the pathophysiology of AIDD. Alternative pathways involving ACE2, Ang receptors and Ang-(1-7) have been implicated in regulating immune responses and tissue homeostasis within the skin microenvironment. Understanding the intricate involvement of the RAS in AIDD may provide novel therapeutic opportunities. Targeting specific components of the RAS, such as angiotensin receptor blockers (ARBs), ACE inhibitors (ACEIs) or alternative RAS pathway modulators, could potentially ameliorate inflammatory responses, reduce tissue damage and lessen disease manifestations. Further research is warranted to outline the exact mechanisms underlying RAS-mediated immune dysregulation in AIDD. This abstract aims to provide a concise overview of the intricate interplay between the RAS and AIDD. Therefore, we elaborate a systematic review of the potential challenge of RAS in the AIDD, including psoriasis, systemic sclerosis, vitiligo, lupus erythematosus and many more.

Association amongst human A1166C polymorphism of the angiotensin II type 1 receptor gene with coronary artery disease in the Iraqi population

Purpose

Coronary artery disease (CAD) is a major cause of death worldwide. There is relatively little data available on the genetic susceptibility to CAD in the Iraqi population. We have therefore investigated the association between angiotensin II type 1 receptor gene polymorphism A1166C and the presence of CAD in a sample of the Iraqi population.

Methods

This case-control study enrolled 150 CAD patients, with CAD confirmed by coronary angiography, and 200 controls. The AT1R polymorphism A1166C was analyzed by the allele-specific polymerase chain reaction (AS-PCR) technique. Serum analyses, such as lipid concentrations, were measured and analyzed.

Results

The C allele and CC genotype frequencies were significantly higher in patients with CAD compared to the controls. Logistic regression analysis showed that the codominant, dominant, and recessive models were associated with risk of CAD of (OR = 1.32, 95% CI: 1.2-1.4, P = 0.000; OR = 1.25, 95% CI: 1.1-1.3, P = 0.000, OR = 1.27, 95% CI: 1.1-1.3, P = 0.000, OR = 1.18, 95% CI: 1.0-1.4), respectively. In the patient group, the presence of the mutant C allele was significantly associated with higher levels of CAD risk factors such as total cholesterol (TC) and low-density lipoprotein (LDL).

Conclusion

The study indicated that the A1166C polymorphism may be associated with the presence of CAD in the Iraqi population. The AT1R polymorphism may therefore be a useful marker of susceptibility to CAD.

Novel Insights Into Gene Signatures and Their Correlation With Immune Infiltration of Peripheral Blood Mononuclear Cells in Behcet's Disease

Background

Behcet’s disease (BD) is a chronic inflammatory disease that involves systemic vasculitis and mainly manifests as oral and genital ulcers, uveitis, and skin damage as the first clinical symptoms, leading to gastrointestinal, aortic, or even neural deterioration. There is an urgent need for effective gene signatures for BD’s early diagnosis and elucidation of its underlying etiology.

Methods

We identified 82 differentially expressed genes (DEGs) in BD cases compared with healthy controls (HC) after combining two Gene Expression Omnibus datasets. We performed pathway analyses on these DEGs and constructed a gene co-expression network and its correlation with clinical traits. Hub genes were identified using a protein–protein interaction network. We manually selected CCL4 as a central hub gene, and gene-set enrichment and immune cell subset analyses were applied on patients in high- and low-CCL4 expression groups. Meanwhile, we validated the diagnostic value of hub genes in differentiating BD patients from HC in peripheral blood mononuclear cells using real-time PCR.

Results

Twelve hub genes were identified, and we validated the upregulation of CCL4 and the downregulation of NPY2R mRNA expression. Higher expression of CCL4 was accompanied by larger fractions of CD8 + T cells, natural killer cells, M1 macrophages, and activated mast cells. Receiver operator characteristic curves showed good discrimination between cases and controls based on the expression of these genes.

Conclusion

CCL4 and NPY2R could be diagnostic biomarkers for BD that reveal inflammatory status and predict vascular involvement in BD, respectively.

Genetic variant in the 5' untranslated region of endothelin1 (EDN1) gene in children with primary nephrotic syndrome

Endothelin-1 plays a crucial role in the pathophysiology of nephrotic syndrome (NS) in children. The primary purpose of this study is to evaluate the contribution of the EDN1 (3A/4A; rs1800997) variant to the risk of nephrotic syndrome. This study involves 200 participants (100 healthy controls, 50 steroid-sensitive nephrotic syndromes [SSNS] patients, and 50 steroid-resistant nephrotic syndromes [SRNS] patients]. Genomic DNA has been characterized using the PCR-RFLP technique. The predominant genotype that is common in this study population was the EDN1 3A/3A genotype (NS [75%] and healthy controls [88%]). The prevalence of EDN1 3A/4A genotype and EDN1 4A allele was significantly increased among NS patients compared with healthy subjects (p-value < 0.05). Furthermore, the frequency of the EDN1 (3A/4A; rs1800997) variant was statistically significant among SRNS patients (p-value < 0.05). The EDN1 3A/4A genotype and the EDN1 4A allele were identified as independent risk factors of the nephrotic syndrome among children.

Inflammatory factors, genetic variants, and predisposition for preterm birth

Preterm birth is a major clinical and public health challenge, with a prevalence of 11% worldwide. It is the leading cause of death in children younger than 5 years old and represents 70% of neonatal deaths and 75% of neonatal morbidity. Despite the clinical and public health significance, this condition's etiology is still unclear, and most of the cases are spontaneous. There are several known preterm birth risk factors, including inflammatory diseases and the genetic background, although the underlying molecular mechanisms are far from understood. The present review highlights the research advances on the association between inflammatory-related genes and the increased risk for preterm delivery. The most associated genetic variants are the TNFα rs1800629, the IL1α rs17561, and the IL1RN rs2234663. Moreover, many of the genes discussed in this review are also implicated in pathologies involving inflammatory or autoimmune systems, such as periodontal disease, bowel inflammatory disease, and autoimmune rheumatic diseases. This review presents evidence suggesting a common genetic background to preterm birth, autoimmune and inflammatory diseases susceptibility.