Renin-angiotensin System Genes Research Articles

Angiotensin-converting enzyme I/D gene polymorphism and risk of type 2 diabetes mellitus in Iranian individuals

This study aimed to examine the relationship between type 2 diabetes mellitus (T2DM) and renin-angiotensin system gene polymorphisms in the Iranian population. Additionally, we performed a straightforward meta-analysis of the present articles to better understand this role. A total of 100 Iranian individuals, 50 patients with T2DM, and 50 age-matched healthy individuals were included in this study. DNA was extracted using the salting-out approach, polymerase chain reaction was used to amplify the angiotensin-converting enzyme (ACE) gene, electrophoresis techniques were used, and genotyping was performed. We also searched PubMed, Web of Science, Scopus, and Google Scholar databases for papers published in 2023. We found a significantly higher frequency of I/D genotype in the patient group than in the control group, and the risk of T2DM was 10 times higher in individuals with the I/D genotype (OR, 10 [95% CI, 3.7 to 27]; p < 0.0001) and also 2.85 time higher in individuals with the D allele OR, 2.85 [95% CI, 1.55 to 5.24]; p < 0.001). The ACE polymorphism alleles D and I/D genotypes may increase the risk of developing T2DM in an Iranian population.

Upregulation of the Renin-Angiotensin System Is Associated with Patient Survival and the Tumour Microenvironment in Glioblastoma.

Glioblastoma is a highly aggressive disease with poor survival outcomes. An emerging body of literature links the role of the renin-angiotensin system (RAS), well-known for its function in the cardiovascular system, to the progression of cancers. We studied the expression of RAS-related genes (ATP6AP2, AGTR1, AGTR2, ACE, AGT, and REN) in The Cancer Genome Atlas (TCGA) glioblastoma cohort, their relationship to patient survival, and association with tumour microenvironment pathways. The expression of RAS genes was then examined in 12 patient-derived glioblastoma cell lines treated with chemoradiation. In cases of glioblastoma within the TCGA, ATP6AP2, AGTR1, ACE, and AGT had consistent expressions across samples, while AGTR2 and REN were lowly expressed. High expression of AGTR1 was independently associated with lower progression-free survival (PFS) (p = 0.01) and had a non-significant trend for overall survival (OS) after multivariate analysis (p = 0.095). The combined expression of RAS receptors (ATP6AP2, AGTR1, and AGTR2) was positively associated with gene pathways involved in hypoxia, microvasculature, stem cell plasticity, and the molecular characterisation of glioblastoma subtypes. In patient-derived glioblastoma cell lines, ATP6AP2 and AGTR1 were upregulated after chemoradiotherapy and correlated with an increase in HIF1A expression. This data suggests the RAS is correlated with changes in the tumour microenvironment and associated with glioblastoma survival outcomes.

Renin-angiotensin system gene polymorphism and aging

A personalized healthy aging program, aimed at preservation of functional capacities in old ages, should consider genetic (hereditary) factors that determine the structure and functions of body organs and systems, and their age-related changes. Individual genetic characteristics of a person can influence the aging process. For this reason, recent research focuses on identifying genetic mechanisms of aging and longevity associated with multifactorial diseases. Renin-angiotensin system (RAS) contributes to the development of pathological conditions leading to cardiovascular diseases, cognitive changes, disorders of auditory and visual analyzers, and may determine the preservation of functional capacities in older adults. We present a literature review of the role of the RAS gene polymorphisms in the aging processes. The results of the synthesis of Russian and international literature indicated the contribution of polymorphic variants of the angiotensinogen (AGT), angiotensin-converting enzyme (ACE), and angiotensin II receptor type 1 (AGTR1) genes to the development of pathological conditions and the associated decreases in functional capacities of an elderly person. Testing for these polymorphisms can be of a practical importance for personified health assessment and development of timely preventive interventions aimed at improving life expectancy and quality of life among older adults.

Transcriptomics-based analysis reveals the nephrotoxic effects of triphenyltin (TPT) on SD rats by affecting RAS, AQPs and lipid metabolism

Triphenyltin (TPT) is a class of organotin compounds that are extensively used in industry and agriculture. They have endocrine-disrupting effects and cause severe environmental contamination. Pollutants may accumulate in the kidneys and cause pathological complications. However, the mechanism of TPT's toxicological effects on the kidney remains unclear. This study aimed to investigate the toxic effects and mechanism of action of TPT exposure on renal impairment in rats. Male SD rats were divided into four groups: the Ctrl group (control group), TPT-L group (0.5 mg/kg/d), TPT-M group (1 mg/kg/d), and TPT-H group (2 mg/kg/d). After 28 days of exposure to TPT, we observed the morphology and structure of kidney tissue using HE, PASM, and Masson staining. We also detected serum biochemical indexes, performed transcriptome sequencing of rat kidney tissue using RNA-seq. Furthermore, protein expression levels were measured through immunohistochemistry and gene expression levels were determined using RT-qPCR. The study results indicated a decrease in kidney weight and relative kidney weight after 28 days of exposure to TPT. Additionally, TPT caused damage to kidney structure and function, as evidenced by HE staining, PASM staining, and serum biochemical tests. Transcriptomics identified 352 DEGs, and enrichment analyses revealed that TPT exposure primarily impacted the renin-angiotensin system (RAS). The expression levels of water channel proteins were reduced, and the expression levels of RAS and lipid metabolism-related genes (Mme, Ace, Fasn, Cyp4a8, Cpt1b and Ppard) were significantly decreased in the TPT-treated group. In summary, exposure to TPT may impair renal structure and function in rats by affecting RAS, AQPs, and lipid metabolism.

Genetic Variations of Angiotensinogen, Angiotensin Converting Enzyme, and Angiotensin Type 1 Receptor with the Risk of Pulmonary Tuberculosis.

There is little data regarding the impact of renin-angiotensin system (RAS) gene polymorphisms on tuberculosis. The current study designed to survey the possible association between RAS polymorphisms and the risk of pulmonary tuberculosis (PTB) in a sample of the southeast Iranian population. This case-control study was done on 170 PTB patients and 170 healthy subjects. The AGT rs699 C&gt;T, ACE rs4341 C&gt;G and AT1R rs5186 C&gt;A variants were genotyped using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) and ACE rs4646994 (287bp I/D) variant by PCR method. Regarding AT1R rs5186 A&gt;C polymorphism, the findings revealed that AC genotype and C allele significantly decreased the risk of PTB (OR=0.39, 95% CI=0.22-0.67, p=0.001, and OR=0.53, 95% CI=0.25-0.72, p=0.002, C vs. A, respectively). The TC genotype and C allele of AGT rs699 T&gt;C significantly associated with decreased the risk of PTB (OR=0.45, 95% CI=0.28-0.74, p=0.002, TC vs. TT and OR=0.51, 95% CI=0.32-0.80, p=0.005, C vs. T, respectively). The ID genotype of ACE 287bp I/D significantly increased the risk of PTB (OR=1.88, 95% CI=1.12-3.17, p=0.017). Our finding did not support an association between ACE rs4341 C&gt;G variant and the risk of PTB. In summary, the findings revealed an association between AT1R rs5186 A&gt;C, AGT rs699 T&gt;C and ACE 287bp I/D polymorphisms and the risk of PTB in a sample of the southeast Iranian population. Further investigation with higher sample sizes and diverse ethnicities are required to confirm our findings.

Altered Gene Expression Within the Renin-Angiotensin System in Normal Aging and Dementia.

The renin-angiotensin system (RAS) is dysregulated in Alzheimer's disease (AD). In this study, we have explored the hypothesis that an -age--related imbalance in brain RAS is a trigger for RAS dysregulation in AD. We characterized RAS gene expression in the frontal cortex from (i) a cohort of normal aging (n = 99, age range = 19-96 years) and (ii) a case-control cohort (n = 209) including AD (n = 66), mixed dementia (VaD + AD; n = 50), pure vascular dementia (VaD; n = 42), and age-matched controls (n = 51). The AD, mixed dementia, and age-matched controls were further stratified by Braak tangle stage (BS): BS0-II (n = 48), BSIII-IV (n = 44), and BSV-VI (n = 85). Gene expression was calculated by quantitative PCR (qPCR) for ACE1, AGTR1, AGTR2, ACE2, LNPEP, and MAS1 using the 2-∆∆Cq method, after adjustment for reference genes (RPL13 and UBE2D2) and cell-specific calibrator genes (NEUN, GFAP, PECAM). ACE1 and AGTR1, markers of classical RAS signaling, and AGTR2 gene expression were elevated in normal aging and gene expression in markers of protective downstream regulatory RAS signaling, including ACE2, MAS1, and LNPEP, were unchanged. In AD and mixed dementia, AGTR1 and AGTR2 gene expression were elevated in BSIII-IV and BSV-VI, respectively. MAS1 gene expression was reduced at BSV-VI and was inversely related to parenchymal Aβ and tau load. LNPEP gene expression was specifically elevated in VaD. These data provide novel insights into RAS signaling in normal aging and dementia.

Abstract P216: Multiomics Approach To Unravel The Molecular Mechanisms Responsible For Kidney Concentric Arterial And Arteriolar Hypertrophy

Introduction: Experimental or spontaneous mutations of any of the renin-angiotensin system (RAS) genes or treatment with RAS inhibitors in mammals -including humans- lead to kidney concentric arterial and arteriolar hypertrophy (CAAH), a silent, progressive, and severe thickening of the intrarenal arterial tree. Therefore, it is crucial to comprehend the identity and fate changes of the vascular smooth muscle cells (VSMCs) as they switch their phenotype to renin-producing cells (RPC) during the progression of the arteriolar disease. Objective: Using new mouse models and single-cell ‘omic’ approaches available in our lab to assess the chromatin landscape of the RPCs and VSMCs, we aim to identify the genomic hotspots that determine the initiation, evolution, and ultimate fate of the diseased cells. Methods: We generated two murine models. In the first model ( Ren1 c-/- ;Ren1 cCre ;R26R mTmG ) the renin gene is deleted while the cells (renin null cells) are labeled green (GFP+) from embryonic life. In the second model ( SMMHC CreERt2 ; R26R tdTomato ; Ren1 cYFP ) VSMCs are labeled red (tdTomato+) upon tamoxifen injection whereas cells currently expressing renin are labeled yellow (YFP+). Kidney cells expressing the different fluorophores were isolated by Fluorescence Activated Cell Sorting and processed for Single Cell Multiome ATAC (Assay for Transposase-Accessible Chromatin) + Gene Expression, using 10X Genomics Chromium technology. Results: The wall thickness of the afferent arterioles in Ren1 C KO mice was significantly increased when compared to control (4.54 ± 0.17 μm vs 11.57 ± 0.91 μm, P &lt;0.0001). The hypertrophic arterioles were covered along their lengths with cells positive for renin, suggesting that renin cells were involved in the hypertrophy. As the mice got older, SMCs accumulate inwardly and concentrically, obstructing the vessels lumens, leading to focal fibrosis. Conclusion: Our studies showed that deletion of the renin gene led to CAAH. Experiments involving transcriptomics and epigenomics are ongoing to understand the evolution of the CAAH and identify and transcriptional profile changes that occur at the single-cell level.

Altered renin-angiotensin system gene expression in airways of antigen-challenged mice: ACE2 downregulation and unexpected increase in angiotensin 1–7

ObjectiveEvidence suggest that the renin-angiotensin system (RAS) is activated in people with asthma, although its pathophysiological role is unclear. Angiotensin-converting enzyme 2 (ACE2) is the major enzyme that converts angiotensin II to angiotensin 1–7 (Ang-1–7), and is also known as a receptor of SARS-CoV-2. The current study was conducted to identify the change in RAS-related gene expression in airways of a murine asthma model. MethodsThe ovalbumin (OA)-sensitized mice were repeatedly challenged with aerosolized OA to induce asthmatic reaction. Twenty-four hours after the last antigen challenge, the main bronchial smooth muscle (BSM) tissues were isolated. ResultsThe KEGG pathway analysis of differentially expressed genes in our published microarray data revealed a significant change in the RAS pathway in the antigen-challenged mice. Quantitative RT-PCR analyses showed significant increases in the angiotensin II-generating enzymes (Klk1, Klk1b3 and Klk1b8) and a significant decrease in Ace2. Surprisingly, ELISA analyses revealed a significant increase in Ang-1–7 levels in bronchoalveolar lavage (BAL) fluids of the antigen-challenged animals, while no significant change in angiotensin II was observed. Application of Ang-1–7 to the isolated BSMs had no effect on their isometrical tension. ConclusionThe expression of Ace2 was downregulated in the BSMs of OA-challenged mice, while Klk1, Klk1b3 and Klk1b8 were upregulated. Despite the downregulation of ACE2, the level of its enzymatic product, Ang-1–7, was increased in the inflamed airways, suggesting the existence of an unknown ACE2-independent pathway for Ang-1–7 production. The functional role of Ang-1–7 in the airways remains unclear.

INVESTIGATING NEW THERAPEUTIC OPPORTUNITIES FOR HYPERTENSION THROUGH TRANSCRIPTOMIC AND PROTEOMIC ANALYSIS OF THE KIDNEY RENIN-ANGIOTENSIN SYSTEM

Objective: We systematically characterised the expression of all renin-angiotensin system (RAS) genes in the human kidney and searched in silico for new pharmacological therapeutic opportunities to modify RAS. Design and method: We compiled data from open access resources to characterise all components of the RAS pathway. We used transcriptomic profiles of 73 human kidney tissues from the Genotype-Tissue Expression Project, integrated genome-wide DNA genotypes and RNA-sequencing-derived transcriptome profiles of 478 human kidneys from Human Kidney Tissue Resource and, kidney tissue proteomics from 72 samples recruited by Clinical Proteomic Tumour Analysis Consortium. Additionally, we used an independent single-cell RNA sequencing data and gene expression datasets curated from the Kidney Precision Medicine Project (KPMP) and Enrichr (web-based enrichment analysis tool). Lastly, we integrated the Connectivity Map and Drug Gene Interaction Database to identify drug repurposing opportunities for treatment of hypertension targeting the RAS genes. Results: We identified 37 genes encoding components of the RAS pathway with measurable expression in human kidney tissue. 15% of these gene-pairs demonstrated a positive (r&gt;0.5) correlation in kidney expression most consistent with a functionally integrated network of interacting molecules. Angiotensinogen (AGT), the key component of the pathway - showed the highest level of mRNA expression in the liver, and we demonstrated that its hepatic mRNA expression correlates most strongly with its mRNA expression in the kidney (r = 0.71, P = 2.60e-06). Expression levels of mRNA for 92% of RAS genes correlated positively with their protein abundance in the kidney, where renin had the strongest positive correlation (r = 0.64, P&lt;0.01). Enrichr and KPMP revealed that RAS gene expression was enriched in mesangial and epithelial cell types. Existing genetic evidence for correlation between glutamyl aminopeptidase (ENPEP) and systolic blood pressure might relate to its capacity to generate angiotensin III acting on dilator angiotensin II type 2 receptors. This raises potential repurposing opportunities for ENPEP inhibitors like firibastat and tosedostat for the treatment of hypertension. Conclusions: Collectively, this study confirmed synchronized expression of RAS genes in the kidney at both mRNA and protein levels and identified new therapeutic opportunities for treatment of hypertension, through drug repurposing.

Evaluating the brain renin‐angiotensin system (RAS) and sex differences in pre‐clinical models of Alzheimer’s Disease

AbstractBackgroundHypertension is linked to Alzheimer’s Disease (AD) risk, although the mechanisms remain unclear. The renin angiotensin system (RAS), critical for blood pressure homeostasis, is thought to contribute to AD pathology, and targeted RAS therapies are under current clinical investigation. To further evaluate the neurobiological mechanisms of RAS in AD, the current study leveraged two transgenic AD mouse models to compare the behavioral and cognitive deficits and the brain RAS in male and female mice.MethodsA triple‐transgenic mouse model of AD (3xTg‐AD), which exhibits both amyloid beta and tau pathology, was used for in‐house assays, while an RNA‐sequencing database using a novel mouse model on a genetically diverse background (AD‐BXD) (GEO accession number GSE119215) was used to compare expression levels of hippocampal RAS genes at 6 and 14 mos. Morris water maze (MWM) and Y‐maze alternation tests were performed at early (3‐4 mos) and middle (5‐6 mos) time points on 3xTg‐AD mice (n = 8/sex/age/genotype), followed by collection of plasma and whole brain.ResultsCompared to controls, beginning at 3.5 months, 3xTg‐AD male and female mice exhibited deficits in learning assessed by MWM escape latency (p&lt;0.01). However, beginning at 6 months, only 3xTg‐AD females had deficits in memory assessed by Y‐maze alternation below 50% (i.e. chance) (p&lt;0.05). Sex‐dependent deficits are consistent with variability in phenotype beginning at early time points. Next we assessed hippocampal RNA‐sequencing data from the AD‐BXD database. These data demonstrated a sex‐dependent increase in expression of counter‐regulatory RAS genes ACE (p&lt;0.0001) and ACE2 (p&lt;0.05) and decrease in MasR (p&lt;0.01) when comparing 6 and 14 month females, as compared to males and wild‐type controls. There was no change in classical RAS gene expression, indicating that variation in expression of neuroprotective but not classical RAS genes may be more pronounced in aging female mice.ConclusionOur results demonstrate sex and stage‐specific behavioral deficits in the 3xTg‐AD model, which may be linked to changes in hippocampal regulation of the counter‐regulatory arm of brain RAS. Additional studies are needed to further evaluate underlying mechanisms for the role of the neuroprotective arm of the brain RAS in AD and its biomarker and therapeutic targeting potential.

Association of polymorphisms of renin angiotensin system and endothelial nitric oxide synthase genes with premature cardiovascular disease in an Iranian population

IntroductionThe study of polymorphisms and their relationship with diseases is very important for risk assessment. The aim of this study was to determine the relationship between early risk of coronary artery disease(CAD) with renin-angiotensin(RAS) genes and endothelial nitric oxide synthase(eNOS) in a sample of the Iranian population.Methods & materialsIn this cross-sectional study, 63 patients with premature CAD and 72 healthy samples were enrolled. Polymorphism of the promotor region of eNOS- and ACE-I/D (Angiotensin Converting Enzyme-I/D) polymorphism was evaluated. Polymerase chain reaction (PCR) test and PCR-RFLP (Restriction Fragment Length Polymorphism) was performed for ACE and eNOS-786 gene, respectively.ResultsThe frequency of deletion(D) for the ACE gene was significantly higher in patients(96% versus 61%; P < 0.001). Conversely, the number of defective C alleles for the eNOS gene was similar in both groups (p > 0.9).ConclusionACE polymorphism seems to be an independent risk factor for premature CAD.

Identification of the regulatory mechanism of ACE2 in COVID-19-induced kidney damage with systems genetics approach.

Studies showed that SARS-CoV-2 can directly target the kidney and induce renal damage. As the cell surface receptor for SARS-CoV-2 infection, the angiotensin-converting enzyme 2 (ACE2) plays a pivotal role for renal physiology and function. Thus, it is important to understand ACE2 through which pathway influences the pathogenesis of renal damage induced by COVID-19. In this study, we first performed an eQTL mapping for Ace2 in kidney tissues in 53 BXD mice strains. Results demonstrated that Ace2 is highly expressed and strongly controlled by a genetic locus on chromosome 16 in the kidney, with six genes (Dnase1, Vasn, Usp7, Abat, Mgrn1, and Rbfox1) dominated as the upstream modulator, as they are highly correlated with Ace2 expression. Gene co-expression analysis showed that Ace2 co-variates are significantly involved in the renin-angiotensin system (RAS) pathway which acts as a reno-protector. Importantly, we also found that Ace2 is positively correlated with Pdgf family members, particularly Pdgfc, which showed the most association among the 76 investigated growth factors. Mammalian Phenotype Ontology enrichment indicated that the cognate transcripts for both Ace2 and Pdgfc were mainly involved in regulating renal physiology and morphology. Among which, Cd44, Egfr, Met, Smad3, and Stat3 were identified as hub genes through protein-protein interaction analysis. Finally, in aligning with our systems genetics findings, we found ACE2, pdgf family members, and RAS genes decreased significantly in the CAKI-1 kidney cancer cells treated with S protein and receptor binding domain structural protein. Collectively, our data suggested that ACE2 work with RAS, PDGFC, as well as their cognate hub genes to regulate renal function, which could guide for future clinical prevention and targeted treatment for COVID-19-induced renal damage outcomes. KEY MESSAGES: • Ace2 is highly expressed and strongly controlled by a genetic locus on chromosome 16 in the kidney. • Ace2 co-variates are enriched in the RAS pathway. • Ace2 is strongly correlated with the growth factor Pdgfc. • Ace2 and Pdgfc co-expressed genes involved in the regulation of renal physiology and morphology. • SARS-CoV-2spike glycoprotein induces down-regulation of Ace2, RAS, and Pdgfc.

Genetic Association of Angiotensin-converting enzyme 2 ACE-2 (rs2285666) Polymorphism with the Susceptibility of COVID-19 Disease in Iraqi Patients

Significant risks to human health are posed by the 2019 coronavirus illness (COVID-19). SARS coronavirus type 2 receptor, also known as the major enzyme in the renin-angiotensin system (RAS), angiotensin-converting enzyme 2 (ACE-2), connects COVID-19 and RAS. This study was conducted with the intention of determining whether or not RAS gene polymorphisms and ACE-2 (G8790A) play a part in the process of predicting susceptibility to infection with COVID-19. In this study 127 participants, 67 of whom were deemed by a physician to be in a severe state of illness, and 60 of whom were categorized as "healthy controls" .The genetic study included an extraction of genomic DNA from blood samples of each covid 19 patients and healthy controls, then amplification the site of SNP (rs2285666) Within the ACE2 gene by using specific primers, sequencing PCR products, and genotyping to detect the role of the ACE-2 gene (rs2285666) in the incidence of COVID-19. ACE-2 (rs2285666) is statistically associated to COVID-19. The COVID-19 group had 65.67 %of individuals with the wild-type homozygous genotype (GG) and 20% in the control group, while the control group had 63.33% of individuals with the mutant genotype (AA). Consequently, the wild-type homozygous (GG) and allele (G) may be considered a risk factor (etiological fraction E. F) for COVID-19 in Iraqi patients, whereas the mutant homozygous (AA) and allele (A) may be considered a protective factor (preventive fraction). The findings of the present study reveal that carriers of the GG genotype of ACE2 (rs2285666) are substantially more susceptible to COVID-19.

Polymorphisms in the Renin-Angiotensin System and eNOS Glu298Asp Genes Are Associated with Increased Risk for Essential Hypertension in a Mexican Population.

Essential hypertension is the result of modifiable and genetic factors, and it is associated with increased risk for atherothrombosis. Some polymorphisms are associated with hypertensive disease. The objective was to analyze the association between eNOS Glu298Asp, MTHR C677T, AGT M235T, AGT T174M, and A1166C and ACE I/D polymorphisms with essential hypertension in the Mexican population. In the present study, 224 patients with essential hypertension and 208 subjects without hypertension were included. The Glu298Asp, C677T, M235T, T174M, A1166C, and I/D polymorphisms were determined by the PCR-RFLP technique. We found statistical differences in age, gender, BMI, systolic and diastolic blood pressure, and total cholesterol between control and cases. However, we found no significant differences in HbA1c and triglycerides between both groups. We observed statistical significant differences in the genotype distribution of Glu298Asp (P = 0.001), I/D (P = 0.02), and M235T (P = 0.004) polymorphisms between both groups. In contrast, there were no differences related to distribution of genotypes of MTHFR C677T (P = 0.12), M174T (P = 0.46), and A1166C (P = 0.85) between cases and control groups. We identified that Glu298Asp, I/D, and M234T polymorphisms represented an increased risk for essential hypertension and those genetic variants could contribute to the presence of endothelial dysfunction and vasopressor effect, hyperplasia, and hypertrophy of smooth muscle cells, which had an impact for hypertension. In contrast, we found no association between C677C, M174T, and A1166C polymorphisms and hypertensive disease. We suggested that those genetic variants could be identified in individuals with high risk to avoid hypertension and thrombotic disease.

Genetic Variations in Angiotensinogen Gene and Risk of Preeclampsia: A Pilot Study

Preeclampsia (PE) is a typical hypertensive disorders of pregnancy (HDP) which can cause substantial morbidity and mortality in both pregnant women and fetuses. The renin-angiotensin system (RAS) genes are the main HDP-causing genes, and Angiotensinogen (AGT) as the initial substrate can directly reflect the activity of the entire RAS. However, the association between AGT SNPs and PE risk has rarely been confirmed. This study was carried out to determine whether AGT SNPs could affect the risk of PE in 228 cases and 358 controls. The genotyping result revealed that the AGT rs7079 TT carrier was related to increased PE risk. Further stratified analysis illustrated that the rs7079 TT genotype significantly increased the PE risk in subgroups of Age < 35, BMI < 25, Albumin (ALB) ≥ 30 and Aspartate aminotransferase (AST) < 30. These findings demonstrated that the rs7079 might be a promising candidate SNP strongly associated with PE susceptibility.

Safety and Efficacy of Dietary Epigallocatechin Gallate Supplementation in Attenuating Hypertension via Its Modulatory Activities on the Intrarenal Renin-Angiotensin System in Spontaneously Hypertensive Rats.

This study aimed to identify the no-observed-adverse-effect level (NOAEL) of dietary epigallocatechin gallate (EGCG) supplementation and its possible antihypertensive and nutrigenomics effects in modulating intrarenal renin-angiotensin system (RAS) gene expression in spontaneously hypertensive rats (SHR). EGCG (50, 250, 500 or 1000 mg/kg b.w. i.g., once daily) was administered to SHR for 28 days. All the SHR survived with no signs of systemic toxicity. Increased alanine aminotransferase (ALT), aspartate aminotransferase (AST) and thiobarbituric acid reactive substances (TBARS) were evident in SHR supplemented with 500 and 1000 mg/kg b.w. but not in those supplemented with lower doses of EGCG. Subsequently, the NOAEL of EGCG was established at 250 mg/kg b.w., and the same protocol was replicated to assess its effects on blood pressure and renal RAS-related genes in SHR. The systolic blood pressure (SBP) of the EGCG group was consistently lower than the control group. The mRNA levels of cortical Agtr2 and Ace2 and medullary Agtr2, Ace and Mas1 were upregulated while medullary Ren was downregulated in EGCG group. Statistical analysis showed that SBP reduction was associated with the changes in medullary Agtr2, Ace, and Ren. Dietary EGCG supplementation exhibits antihypertensive and nutrigenomics effects through activation of intrarenal Ace and Agtr2 and suppression of Ren mediators, while a high dose of EGCG induced liver damage in SHR. In future clinical studies, liver damage biomarkers should be closely monitored to further establish the safety of the long-term use of EGCG.

Shenkang injection improves chronic kidney disease by inhibiting multiple renin-angiotensin system genes by blocking the Wnt/β-catenin signalling pathway.

Chronic kidney disease (CKD) is a major worldwide public health problem. The increase in the number of patients with CKD and end-stage kidney disease requesting renal dialysis or transplantation will progress to epidemic proportions in the next several decades. Although blocking the renin-angiotensin system (RAS) has been used as a first-line standard therapy in patients with hypertension and CKD, patients still progress towards end-stage kidney disease, which might be closely associated with compensatory renin expression subsequent to RAS blockade through a homeostatic mechanism. The Wnt/β-catenin signalling pathway is the master upstream regulator that controls multiple intrarenal RAS genes. As Wnt/β-catenin regulates multiple RAS genes, we inferred that this pathway might also be implicated in blood pressure control. Therefore, discovering new medications to synchronously target multiple RAS genes is necessary and essential for the effective treatment of patients with CKD. We hypothesized that Shenkang injection (SKI), which is widely used to treat CKD patients, might ameliorate CKD by inhibiting the activation of multiple RAS genes via the Wnt/β-catenin signalling pathway. To test this hypothesis, we used adenine-induced CKD rats and angiotensin II (AngII)-induced HK-2 and NRK-49F cells. Treatment with SKI inhibited renal function decline, hypertension and renal fibrosis. Mechanistically, SKI abrogated the increased protein expression of multiple RAS elements, including angiotensin-converting enzyme and angiotensin II type 1 receptor, as well as Wnt1, β-catenin and downstream target genes, including Snail1, Twist, matrix metalloproteinase-7, plasminogen activator inhibitor-1 and fibroblast-specific protein 1, in adenine-induced rats, which was verified in AngII-induced HK-2 and NRK-49F cells. Similarly, our results further indicated that treatment with rhein isolated from SKI attenuated renal function decline and epithelial-to-mesenchymal transition and repressed RAS activation and the hyperactive Wnt/β-catenin signalling pathway in both adenine-induced rats and AngII-induced HK-2 and NRK-49F cells. This study first revealed that SKI repressed epithelial-to-mesenchymal transition by synchronously targeting multiple RAS elements by blocking the hyperactive Wnt/β-catenin signalling pathway.

SNPs of ACE1 (rs4343) and ACE2 (rs2285666) genes are linked to SARS-CoV-2 infection but not with the severity of disease

COVID-19 and the renin-angiotensin system (RAS) are linked by angiotensin-converting enzyme 2 (ACE2), a key enzyme in RAS that has been validated as a SARS-CoV-2 receptor. Functional ACE1/ACE2 gene polymorphisms may lead to the imbalance between ACE/ACE2 ratio and thus generating RAS imbalance that is associated with higher degrees of lung damage in ARDS that may contribute to the COVID-19 infection outcome. Herein, we investigated the role of RAS gene polymorphisms, ACE1 (A2350G) and ACE2 (G8790A) as risk predictors for susceptibility and severity of COVID-19 infection. A total of 129 included: negative controls without a history of COVID-19 infection (n = 50), positive controls with a history of COVID-19 infection who were not hospitalized (n = 35), and patients with severe COVID-19 infection who were hospitalized in the intensive care unit (n = 44). rs4343 of ACE and rs2285666 of ACE2 were genotyped using PCR–RFLP method. Our results indicated that susceptibility to COVID-19 infection was associated with age, GG genotype of A2350G (Pa = 0.01; OR 4.7; 95% CI 1.4–15.1 and Pc = 0.040; OR 2.5; 95% CI 1.05–6.3) and GG genotype of G8790A (Pa = 0.044; OR 6.17; 95% CI 1.05–35.71 and Pc = 0.0001; OR 5.5; 95% CI 2.4–12.4). The G allele of A2350G (Pa = 0.21; OR 1.74; 95% CI 0.73–4.17 and Pc = 0.007; OR 2.1; 95% CI 1.2–3.5) and G allele of G8790A (Pa = 0.002; OR 4.26; 95% CI 1.7–10.65 and Pc = 0.0001; OR 4.7; 95% CI 2.4–9.2) were more frequent in ICU-admitted patients and positive control group. Also lung involvement due to COVID-19 infection was associated with age and the comorbidities such as diabetes. In conclusion, our findings support the association between the wild genotype (GG) of ACE2 and homozygote genotype (GG) of ACE1 and sensitivity to COVID-19 infection, but not its severity. However, confirmation of this hypothesis requires further studies with more participants.

Pak2 Regulation of Nrf2 Serves as a Novel Signaling Nexus Linking ER Stress Response and Oxidative Stress in the Heart.

Endoplasmic Reticulum (ER) stress and oxidative stress have been highly implicated in the pathogenesis of cardiac hypertrophy and heart failure (HF). However, the mechanisms involved in the interplay between these processes in the heart are not fully understood. The present study sought to determine a causative link between Pak2-dependent UPR activation and oxidative stress via Nrf2 regulation under pathological ER stress. We report that sustained ER stress and Pak2 deletion in cardiomyocytes enhance Nrf2 expression. Conversely, AAV9 mediated Pak2 delivery in the heart leads to a significant decrease in Nrf2 levels. Pak2 overexpression enhances the XBP1-Hrd1 UPR axis and ameliorates tunicamycin induced cardiac apoptosis and dysfunction in mice. We found that Pak2 deletion and altered proteostasis render Nrf2 detrimental by switching from its antioxidant role to renin-angiotensin aldosterone system (RAAS) gene regulator. Mechanistically, Pak2 mediated Hrd1 expression targets Nrf2 for ubiquitination and degradation thus preventing its aberrant activation. Moreover, we find a significant increase in Nrf2 with a decrease in Pak2 in human myocardium of dilated heart disease. Using human-induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs), we find that Pak2 is able to ameliorate Nrf2 induced RAAS activation under ER stress. These findings demonstrate that Pak2 is a novel Nrf2 regulator in the stressed heart. Activation of XBP1-Hrd1 is attributed to prevent ER stress-induced Nrf2 RAAS component upregulation. This mechanism explains the functional dichotomy of Nrf2 in the stressed heart. Thus, Pak2 regulation of Nrf2 homeostasis may present as a potential therapeutic route to alleviate detrimental ER stress and heart failure.

50P Targeting the renin-angiotensin system in gastric cancer therapeutics

Overactivation of the renin-angiotensin system (RAS) is frequently associated with harmful consequences in various diseases. In the present study, we investigated association between overexpression of the key regulator genes of RAS and overall survival in gastric cancer patients.