Renin-angiotensin Research Articles

Angiotensin II Induces Vascular Endothelial Dysfunction by Promoting Lipid Peroxidation-Mediated Ferroptosis via CD36

Angiotensin II (Ang II) is an effective vasoconstriction peptide, a major effector molecule of the renin–angiotensin–aldosterone system (RAAS) and one of the important causes of endothelial dysfunction. Ferroptosis is considered to be involved in the occurrence and development of cardiovascular diseases. This study is dedicated to exploring the role and mechanism of Ang II-induced ferroptosis in HUVECs and to finding molecular targets for vascular endothelial injury and dysfunction during the progression of hypertension. In this study, we found that with the increase in exposure concentration, the intracellular ROS content and apoptosis rate increased significantly, the NO release decreased significantly in the medium- and high-concentration groups and the ET-1 content in the high-concentration group increased significantly. The expression of ZO-1 protein was significantly decreased in the high-concentration group. The expression of p-eNOS, VE-cadherin and Occludin protein showed a dose-dependent downward trend, while the ICAM-1 protein showed an upward trend. Ang II caused lipid metabolism disorders in HUVECs, and the PL–PUFAs associated with ferroptosis were significantly increased. In addition, Ang II promoted a significant increase in intracellular free Fe2+ content and MDA and a significant decrease in GSH content. Furthermore, the expression of GPX4, SLC7A11 and SLC3A2 was down-regulated, the expression of ACSL4, LPCAT3 and ALOX15 was up-regulated, and the ratio of p-cPLA2/cPLA2 was increased. After the intervention of ferroptosis inhibitor Fer-1, the injury and dysfunction of HUVECs induced by Ang II were significantly rescued. Immunofluorescence results showed that the expression of CD36 showed a significant increasing trend and was localized in the cytoplasm. Over-expression of CD36 promoted Ang II-induced ferroptosis and endothelial dysfunction. In conclusion, Ang II induces the injury of HUVECs, decreases vascular diastole and endothelial barrier-related molecules, and increases vascular constriction and adhesion-related molecules, which may be related to CD36 and its mediated lipid peroxidation and ferroptosis signals.

Dependent censoring bias assessment using inverse probability of censoring weights: Type 2 diabetes mellitus risk in patients initiating bisoprolol versus other antihypertensives in a Clinical Practice Research Datalink cohort study.

Dependent censoring involves a preferential attrition of a subgroup of interest; occurring in survival analysis, it may impact interpretation by introducing a selection bias. To assess the potential bias in a comparison of bisoprolol to other antihypertensives in terms of Type 2 diabetes mellitus (T2DM) incidence, inverse probability of censoring weights (IPCW) was used. It was further used to contextualize results obtained through competing risks analysis. Two estimands were considered to assess T2DM incidence while accounting for deviations from the initial antihypertensive monotherapy (DFM). A hypothetical estimand using IPCW, treating DFM as censoring, was interpreted together with a 'while-on-treatment' estimand, treating DFM as a competing risk. We illustrated our application with a cohort study based on Clinical Practice Research Datalink (CPRD) including 267,352 patients with newly diagnosed arterial hypertension between 2000 and 2017, initiating antihypertensive monotherapy among bisoprolol, other beta-blockers, renin-angiotensin system drugs (ACEi/ARB), diuretics and calcium-channel blockers. A mild dependent censoring process was hypothesized, leading to slight overestimation of T2DM incidence. Although subject to some limitations, a nonsignificant trend toward an excess of risk associated with ACEi/ARB was yielded consistently by IPCW and competing risks analyses. Conversely, in comparisons of bisoprolol versus either diuretics, other beta-blockers or calcium channel blockers, no significant differences or critical dependent censoring impact were found. Concurrent use of complementary estimands allowed formulating a refined interpretation of our findings: though not significant, the trend toward an excess of T2DM risk associated with a ACEi/ARB monotherapy compared with bisoprolol is likely not originating only from the minor dependent censoring. Reassessing identical estimands in other cohorts would provide insights to corroborate or refute this result.

Cross talk on therapeutic strategies: natriuretic peptides and inhibiting neprilysin in hypertension management.

Hypertension, a prevalent cardiovascular condition globally, remains a significant public health concern due to its association with increased cardiovascular morbidity and mortality. Despite the availability of various antihypertensive therapies, achieving optimal blood pressure control in patients remains a challenge. Valsartan/sacubitril (ARNi), marketed as Entresto by Novartis, combines valsartan, an angiotensin receptor blocker, with sacubitril, an inhibitor of neprilysin. Neprilysin is responsible for breaking down natriuretic peptides and other vasoactive substances. Inhibiting neprilysin prevents the degradation of natriuretic peptides, enhancing their beneficial effects on blood pressure regulation. Natriuretic Peptides, including atrial natriuretic peptide (ANP) and brain natriuretic peptides (BNP), play pivotal roles in regulating blood pressure and cardiovascular homeostasis by promoting vasodilation, natriuresis, and antagonizing the renin-angiotensin-aldosterone system. Therefore, this combo drug lessens sensitivity to natriuretic peptides and tackles the processes in hypertension that activate the renin-angiotensin-aldosterone system. This review provides an overview of how natriuretic peptides (NPs) contribute to blood pressure regulation for the treatment of hypertension through inhibiting neprilysin. It highlights the ARNi's dual action that works synergistically by blocking the harmful effects of angiotensin II on blood vessels while simultaneously increasing the levels of beneficial natriuretic peptides. Schematic representation of the mechanism of action of ARNi. Abbreviation: -Renin angiotensin aldosterone system (RAAS), Natriuretic peptides (NP), Atrial Natriuretic peptide (ANP), Brain natriuretic peptide (BNP), C-type natriuretic peptide (CNP), Angiotensin II (Ang II), Angiotensin receptor neprilysin inhibitor (ARNI).

Characterization of novel ACE2 mRNA transcripts: The potential role of alternative splicing in SARS-CoV-2 infection.

The human angiotensin converting enzyme 2 (ACE2) gene encodes a type I transmembrane protein, which is homologous to angiotensin I-converting enzyme (ACE) and belongs to the angiotensin-converting enzyme family of dipeptidyl carboxypeptidases. As highlighted by the COVID-19 pandemic, ACE2 is not only crucial for the renin-angiotensin-aldosterone system (RAAS), but also displays great affinity with the SARS-CoV-2 spike protein, representing the major receptor of the virus. Given the significance of ACE2 in COVID-19, especially among cancer patients, the present study aims to explore the transcriptional landscape of ACE2 in human cancer and non-cancerous cell lines through the design and implementation of a custom targeted long-read sequencing approach. Bioinformatics analysis of the massive parallel sequencing data led to the identification of novel ACE2 mRNA splice variants (ACE2 sv.7-sv.12) that demonstrate previously uncharacterized exon-skipping events as well as 5' and/or 3' alternative splice sites. Demultiplexing of the sequencing data elucidated the differential expression profile of the identified splice variants in multiple human cell types, whereas in silico analysis suggests that some of the novel splice variants could produce truncated ACE2 isoforms with altered functionalities, potentially influencing their interaction with the SARS-CoV-2 spike protein. In summary, our study sheds light on the complex alternative splicing landscape of the ACE2 gene in cancer cell lines, revealing novel splice variants that could have significant implications for SARS-CoV-2 susceptibility in cancer patients. These findings contribute to the increased understanding of ACE2's role in COVID-19 and highlight the importance of considering alternative splicing as a key factor in viral pathogenesis. Undoubtably, further research is needed to explore the functional roles of these variants and their potential as therapeutic targets in the ongoing fight against COVID-19.

Influence of intestinal microbiota on the metabolism of main cardiotropic drugs

The intestinal microbiota is one of the most important pathogenetic links in the development of cardiovascular diseases. Every year the world scientific community finds new interactions at the level of signaling molecules, metabolites and microorganisms, identifying more and more patterns and cause-and-effect relationships which indicate the commonality of the intestinal microbiota (GM) and cardiovascular diseases. The state of the host's intestinal community, its qualitative and quantitative composition, directly and indirectly affects the fundamental pathogenetic mechanisms of the development of cardiovascular diseases. Despite the fact that there are scientifically based methods of treatment, cardiovascular diseases remain the leading cause of death in the world. This phenomenon is partly due to wide variations in individual response to cardiovascular drugs. The pharmacological effects of cardiotropic drugs are quite different even within groups of patients comparable in age and gender. Every year intestinal microbiota is more and more evident to be responsible for this intraspecific variability. Gut microbes influence drug metabolism in several pharmacokinetic ways, and conversely, drugs can have significant effects on the microbiome and therefore pharmacodynamic processes. Drugs can alter the gut microenvironment and microbial metabolism, influence bacterial growth, thereby changing the composition and functions of the microbial community. One of the most important functions of GM, related to “intestinal-cardiovascular system”, is participation in the metabolism of major cardiotropic medications, such as digoxin, statins, ezetimibe, antithrombotic drugs, calcium channel blockers (CCBs), beta blockers (BB), gliflozins and inhibitors of the renin-angiotensin-aldosterone system (RAAS).

Transgenic rat with ubiquitous expression of angiotensin-(1-7)-producing fusion protein: a new tool to study the role of protective arm of the renin-angiotensin system in the pathophysiology of cardio-renal diseases.

The aim of the present study was to assess systemic circulatory and tissue activities of both the classical arm and of the alternative arm of the renin-angiotensin system (RAS) in a new transgenic rat line (TG7371) that expresses angiotensin-(1-7) (ANG 1-7)-producing fusion protein; the results were compared with the activities measured in control transgene-negative Hannover Sprague-Dawley (HanSD) rats. Plasma and tissue concentrations of angiotensin II (ANG II) and ANG 1-7, and kidney mRNA expressions of receptors responsible for biological actions of ANG II and ANG 1-7 [i.e. ANG II type 1 and type 2 (AT1 and AT2) and Mas receptors] were assessed in TG7371 transgene-positive and in HanSD rats. We found that male TG7371 transgene-positive rats exhibited significantly elevated plasma, kidney, heart and lung ANG 1-7 concentrations as compared with control male HanSD rats; by contrast, there was no significant difference in ANG II concentrations and no significant differences in mRNA expression of AT1, AT2 and Mas receptors. In addition, we found that in male TG7371 transgene-positive rats blood pressure was lower than in male HanSD rats. These data indicate that the balance between the classical arm and the alternative arm of the RAS was in male TGR7371 transgene-positive rats markedly shifted in favor of the latter. In conclusion, TG7371 transgene-positive rats represent a new powerful tool to study the long-term role of the alternative arm of the RAS in the pathophysiology and potentially in the treatment of cardio-renal diseases.

Mechanistic Insights Into Redox Damage of the Podocyte in Hypertension.

Podocytes are specialized cells within the glomerular filtration barrier, which are crucial for maintaining glomerular structural integrity and convective ultrafiltration. Podocytes exhibit a unique arborized morphology with foot processes interfacing by slit diaphragms, ladder-like, multimolecular sieves, which provide size and charge selectivity for ultrafiltration and transmembrane signaling. Podocyte dysfunction, resulting from oxidative stress, dysregulated prosurvival signaling, or structural damage, can drive the development of proteinuria and glomerulosclerosis in hypertensive nephropathy. Functionally, podocyte injury leads to actin cytoskeleton rearrangement, foot process effacement, dysregulated slit diaphragm protein expression, and impaired ultrafiltration. Notably, the renin-angiotensin system plays a pivotal role in podocyte function, with beneficial AT2R (angiotensin receptor 2)-mediated nitric oxide (NO) signaling to counteract AT1R (angiotensin receptor 1)-driven calcium (Ca2+) influx and oxidative stress. Disruption of this balance contributes significantly to podocyte dysfunction and drives albuminuria, a marker of kidney damage and overall disease progression. Oxidative stress can also lead to sustained ion channel-mediated Ca2+ influx and precipitate cytoskeletal disorganization. The complex interplay between GPCR signaling, ion channel activation, and redox injury pathways underscores the need for additional research aimed at identifying targeted therapies to protect podocytes and preserve glomerular function. Earlier detection of albuminuria and podocyte injury through routine noninvasive diagnostics will also be critical in populations at the highest risk for the development of hypertensive kidney disease. In this review, we highlight the established mechanisms of oxidative stress-mediated podocyte damage in proteinuric kidney diseases, with an emphasis on a hypertensive renal injury. We will also consider emerging therapies that have the potential to selectively protect podocytes from redox-related injury.

Abstract 4123806: Early Findings on the Impact of Renin-Angiotensin-Aldosterone System Inhibitors on Bicuspid Aortic Valve Disease Progression: A Single Center Cohort Study

Introduction: Patients with a bicuspid aortic valve (BAV) often have an associated aortopathy, increasing their risk of aortic dissection. Currently, there is no proven therapy to stabilize the growth of BAV aortopathy. This study aimed to assess the effect of cardioprotective medications, specifically renin-angiotensin-aldosterone system inhibitors (RAASi), on the progression of aortic dilation in adult BAV patients. Methods: A retrospective cohort study was conducted including adult patients with BAV followed at our center between 1996-2020. All patients had echocardiography imaging with at least 5 years of follow-up. The cohort was divided based on the chronic use of RAASi, as determined by pharmacy check-out data. The primary endpoint was defined as either the progression of ascending aortic diameter ≥ 4.5 cm or surgery for ascending aortic replacement. Results: The study included 262 patients with a mean age of 54.3±19.5 years, of whom 75.2% (n=197) were male, and 34.7% (n=44) had a diagnosis of hypertension. At baseline, the average size of the ascending aorta was 4.2±4.1 mm and 3.5±4.0 mm at the level of the aortic sinuses. The average follow-up time was 5.8±0.8 years. During follow-up, 23 patients underwent ascending aortic replacement with concurrent aortic valve replacement, 66 patients experienced progression of ascending aortic diameter ≥ 4.5 cm, and 2 patients died. Patients using RAASi (n=40) had a lower incidence of the primary endpoint compared to those without RAASi chronic therapy (12.8% vs. 24.8%, p=0.147). Multivariate analysis indicated that patients without RAASi chronic therapy had a significantly increased risk of the primary endpoint (HR=2.87, 95% CI [1.03-8.01], p=0.43). Conclusions: Our early findings suggest that RAASi may have a preventative role in the progression of BAV aortopathy.

Evidence for Aldosterone Antagonism in Heart Failure

Activation of the renin–angiotensin–aldosterone system is the ultimate pathophysiological hallmark in heart failure. Though aldosterone primarily appears to regulate electrolyte homeostasis by acting on distal nephrons in the kidneys, its effects are far-reaching across the cardiovascular system as its receptors are also expressed in vascular smooth muscle cells, endothelial cells, macrophages and cardiomyocytes. Aldosterone excess leads to vascular stiffness, vasoconstriction, endothelial dysfunction, inflammation, oxidative stress, cardiac fibrosis and hypertrophy, atherogenesis and thrombosis. Hence, aldosterone antagonism is an attractive proposition for heart failure management. The first-generation non-selective mineralocorticoid receptor antagonist spironolactone produced a spectacular reduction of cardiovascular outcomes in the seminal RALES study, while the selective second-generation congener eplerenone boasts two positive studies: EPHESUS and EMPHASIS-HF. The TOPCAT trial indicated that a specific subgroup of patients with heart failure with preserved ejection fraction may benefit from targeted therapy of mineralocorticoid receptor antagonists. Newer-generation non-steroidal mineralocorticoid antagonists and aldosterone synthase inhibitors are being evaluated in randomised trials.

The potential for improving cardio-renal outcomes in chronic kidney disease with the aldosterone synthase inhibitor vicadrostat (BI 690517): a rationale for the EASi-KIDNEY trial.

Patients with chronic kidney disease (CKD) are at risk of progressive loss of kidney function, heart failure, and cardiovascular death despite current proven therapies, including renin-angiotensin system inhibitors (RASi), sodium glucose co-transporter-2 inhibitors (SGLT2i), and statin-based regimens. RASi and SGLT2i reduce risk of CKD progression irrespective of primary cause of kidney disease, suggesting they target final common pathways. Targeting aldosterone overactivity with a nonsteroidal mineralocorticoid receptor antagonist (MRA) also reduces cardiorenal risk in patients with albuminuric diabetic kidney disease already treated with RASi. Together, these observations provide the rationale for trials to assess effects of inhibiting the aldosterone pathway in a broader range of patients with CKD, including those with non-diabetic causes of CKD or low albuminuria. Aldosterone synthase inhibitors (ASi) have emerged as an alternative to MRAs for aldosterone pathway inhibition. Phase II data from 586 patients with albuminuric CKD have shown that 10 mg of an ASi, vicadrostat (BI 690517), reduced urine albumin-to-creatinine ratio by ∼40% compared to placebo with or without concurrent empagliflozin treatment. MRA and ASi increase risk of hyperkalaemia. Combining their use with an SGLT2i may mitigate some of this risk, improving tolerability, and allowing a wider range of patients to be treated (including those with higher levels of blood potassium than in previous trials). The EASi-KIDNEY (NCT06531824) double-blind placebo-controlled trial will test this approach by assessing the safety and cardiorenal efficacy of vicadrostat in combination with empagliflozin in ∼11,000 patients with CKD. It will be sufficiently large to assess effects in patients with and without diabetes separately.

A systematic review and meta-analysis of factors contributing to post-kidney transplant anemia and the effect of erythropoietin-stimulating agents.

The effects of various risk and associated factors on post-kidney transplant anemia (PTA) have not been fully compared and estimated. This meta-analysis aims to elucidate factors contributing to PTA and determine the influence of erythropoietin-stimulating agents (ESAs) on renal outcomes, thus offering potential pathways for enhanced management strategies post-transplant. A systematic review was conducted in electronical database. Studies reporting on risk factors (with cause-effect relationships) and associated factors (without definite cause-effect relationships) of PTA, and the effects of ESAs on post-kidney transplant outcomes, were included. Pooled odds ratios (ORs) and weighted mean differences (WMDs) were analyzed using random-effects models. This systematic review encompassed 38,233 patients from 85 studies. Factors increased PTA risk included African American, older donor age, human antigen leukocyte mismatches, and low pre-transplant hemoglobin levels. Poor allograft function, high interleukine-6, Cytomegalovirus, delayed graft function, allograft rejections, immunosuppressive medications, and renin-angiotensin system blockades were associated with PTA. Native autosomal dominant polycystic kidney disease was a protective factor against PTA. Administration of ESAs with the aim of normalizing hemoglobin levels in patients with chronic allograft dysfunction slowed the decline in eGFR and reduce the risk of death, with a pooled OR of 0.36 (95% CI: 0.14 to 0.89; p = 0.040). The risks and associated factors for PTA have been elucidated, underscoring the need for individualized treatment approaches. Late ESA therapy, aimed at hemoglobin normalization, suggests a renal-protective effect and reduced mortality, which should be considered in the management of PTA. PROSPERO CRD42024545330.

Correlation Between Serum Copeptin and NTproBNP Levels in Heart Failure

Introduction: Heart Failure is a leading cause of morbidity and mortality worldwide. It is associated with upregulation and dysfunction of the renin-angiotensin aldosterone system, the sympathetic nervous system and the vasopressin system. In heart failure, the levels of vasopressin are elevated and out of sync with the osmotic status. Arginine Vasopressin has a half-life of only 20 minutes and is bound to circulating platelets. Hence, it is not useful as a biomarker. Copeptin, a by-product of vasopressin metabolism has been used as a surrogate marker for Arginine Vasopressin in clinical practice. Thus, our study aims to find the use of copeptin in studying heart failure and its use in predicting severity. We also sought to correlate copeptin with NTproBNP the standard biomarker used in heart failure. Methods: Our study was a single-centre cross-sectional observational study involving 90 admitted heart failure patients over 18 months. NYHA Class was used to assess the severity of heart failure. Copeptin levels were measured using Human Copeptin ELISA Kit. Results: In these patients, elevated levels of copeptin and NTproBNP were found. In patients with higher NYHA Class, a greater rise in serum copeptin and NTproBNP levels was noted. Moreover, a strong positive correlation between NTproBNP and copeptin (rho = 0.7) was found in our study. Conclusion: Our study puts forward copeptin as a simple additional cost-effective biomarker for predicting the severity of heart failure.

Social Determinants of Health and Disparities in Guideline-Directed Medical Therapy Optimization for Heart Failure.

Fewer than 20% of eligible patients with heart failure with reduced ejection fraction receive all 4 pillars of guideline-directed medical therapy. Understanding disparities by race, ethnicity, sex, and adverse social determinants of health is necessary to equitably optimize quadruple therapy. Utilizing the American Heart Association's Get With The Guidelines-Heart Failure registry, we examined associations between race and ethnicity, sex, and adverse social determinants of health (insurance type and documented social need [any barrier to accessing health care]) with quadruple therapy optimization (QTO) in patients with heart failure with reduced ejection fraction hospitalized between July 1, 2021, and September 30, 2023, with complete medication data at discharge. We calculated adjusted mean differences (AMDs) in the discharge QTO score (range, 0%-100%) reflecting the proportion of eligible use of renin-angiotensin system inhibitors, β-blockers, mineralocorticoid receptor antagonists, and sodium-glucose cotransporter-2 inhibitors and compared across demographic and adverse social determinants of health groups. Among 82 637 patients (median age, 66 years; 32.5% female; 57.0% non-Hispanic White; 76.4% prior heart failure with reduced ejection fraction), the overall mean QTO score was 56.2% (SD, 25.5). After adjustment, compared with non-Hispanic White individuals, Black (AMD, 2.56 percentage points [95% CI, 2.16-2.96]) and Hispanic individuals (AMD, 0.71 percentage points [95% CI, 0.11-1.31]) had higher QTO scores. Females had higher QTO scores than males (AMD, 1.94 percentage points [95% CI, 1.58-2.31]). Patients with no insurance (AMD, -4.90 percentage points [-5.62 to -4.17]), Medicaid (AMD, -0.45 percentage points [-0.89 to -0.01]), and Medicare (AMD, -1.64 percentage points [-2.10 to -1.18]) had lower QTO scores versus private insurance. Those with an identified social need (n=24 651) had lower QTO scores than those without (AMD, -3.40 percentage points [95% CI, -4.10 to -2.71]). Disparities in QTO were most evident for patients with no insurance, Medicaid, Medicare, or potentially an identified social need. Future efforts should focus on reducing gaps to improve equitable guideline-directed medical therapy use.

Clinical significance of post-COVID-19 in patients with hypertension, taking into account the polymorphism of genes encoding components of the renin-angiotensin system

To date, there has been no consensus on the impact of polymorphism of components of the renin-angiotensin-aldosterone system (RAAS) on the course of a new coronavirus infection or a possible role in post-COVID syndrome. The objective is to study the significance of COVID-19 and gene polymorphism encoding components of renin angiotensin system in patients with hypertension. Materials and methods: A clinical examination was conducted on 116 stage 2 hypertensive patients with uncontrolled hypertension. Of these, 96 underwent mild or moderate COVID-19, 51 before 12 weeks and 45 after 12. Results. Patients in the ongoing symptomatic phase of COVID- 19 had higher systolic blood pressure than those with post COVID syndrome (p1-2 = 0.03659, p1-3 ≤ 0,00001).The association of polymorphisms of genes AGT:704T>C, AGT521C>T, AGTR1:1166A>C, AGTR2:1675G>A, CYP1IB2:-344C>T with gender, BMI and COVID-19 transmission has not been identified. In the symptomatic phase of COVID-19, carriage of the TT genotype for the AGT704 gene was less frequent (p=0.005) compared to the control group. Conclusions. The effect of COVID on an increase in blood pressure in stage 2 hypertensive patients was determined. An association between blood pressure instability and BMI after COVID was established. During the symptomatic COVID phase, there was an association between increased blood pressure and the C allele of AGT gene polymorphisms (T704).

Multi-organ gene expression analysis and network modeling reveal regulatory control cascades during the development of hypertension in female spontaneously hypertensive rat.

Hypertension is a multifactorial disease with stage-specific gene expression changes occurring in multiple organs over time. The temporal sequence and the extent of gene regulatory network changes occurring across organs during the development of hypertension remain unresolved. In this study, female spontaneously hypertensive (SHR) and normotensive Wistar Kyoto (WKY) rats were used to analyze expression patterns of 96 genes spanning inflammatory, metabolic, sympathetic, fibrotic, and renin-angiotensin (RAS) pathways in five organs, at five time points from the onset to established hypertension. We analyzed this multi-dimensional dataset containing ~15,000 data points and developed a data-driven dynamic network model that accounts for gene regulatory influences within and across visceral organs and multiple brainstem autonomic control regions. We integrated the data from female SHR and WKY with published multiorgan gene expression data from male SHR and WKY. In female SHR, catecholaminergic processes in the adrenal gland showed the earliest gene expression changes prior to inflammation-related gene expression changes in the kidney and liver. Hypertension pathogenesis in male SHR instead manifested early as catecholaminergic gene expression changes in brainstem and kidney, followed by an upregulation of inflammation-related genes in liver. RAS-related gene expression from the kidney-liver-lung axis was downregulated and intra-adrenal RAS was upregulated in female SHR, whereas the opposite pattern of gene regulation was observed in male SHR. We identified disease-specific and sex-specific differences in regulatory interactions within and across organs. The inferred multi-organ network model suggests a diminished influence of central autonomic neural circuits over multi-organ gene expression changes in female SHR. Our results point to the gene regulatory influence of the adrenal gland on spleen in female SHR, as compared to brainstem influence on kidney in male SHR. Our integrated molecular profiling and network modeling identified a stage-specific, sex-dependent, multi-organ cascade of gene regulation during the development of hypertension.

Nephroprotective effect of SGLT2 inhibitors in elderly patients with type 2 diabetes mellitus and hypertension: a real-world population-based cohort study

ABSTRACT Objectives This study aimed to investigate the nephroprotective effect of sodium-glucose cotransporter 2 inhibitors (SGLT2i) in elderly patients with type 2 diabetes mellitus (T2DM) and hypertension based on real-world clinical data. The study aimed to provide a theoretical basis for evidence-based pharmacological treatment of chronic kidney disease in this population. Methods The ‘Health Cloud’ platform of the Shanghai Municipal Health Commission was employed to identify and screen elderly patients with T2DM and hypertension. The propensity score matching cohort was further constructed to estimate the effect of SGLT2i on the risk of rapid decline in renal function (∆eGFR≤-5 ml/min/1.73 m2 or ∆eGFR%≤-5%). Multiple sensitivity analyses were conducted to assess the robustness of the results. Results After propensity score matching, no significant differences of covariates were identified between the SGLT2i and non-SGLT2i groups. The results of multivariate logistic models demonstrated a consistent and inverse correlation between SGLT2i use and the risk of rapid eGFR decline, whether defined as ∆eGFR≤-5 ml/min/1.73 m2 (OR = 0.60, 95% CI:0.38-0.96) or ∆eGFR%≤-5%（OR = 0.57, 95% CI:0.37-0.89). In the stratification of renin-angiotensin system inhibitor (RASi) treatment, SGLT2i was associated with a lower risk of rapid eGFR decline in the RASi group (all ORs < 1, p < 0.05), with no interaction between SGLT2i and RASi (all P for interaction > 0.05) detected. Conclusions SGLT2i significantly reduced the risk of rapid eGFR decline in elderly patients with T2DM and hypertension, but the synergistic effect with RASi remains unclear.

Targeting the Renin-Angiotensin System in Obesity-Driven Hyperlipidemia and Hypertension

The renin-angiotensin system (RAS) plays a crucial role in the regulation of blood pressure, fluid balance, and lipid metabolism. Dysregulation of the RAS has been implicated in the pathogenesis of obesity-driven hyperlipidemia and hypertension, two major components of metabolic syndrome that significantly increase the risk of cardiovascular disease. In obese individuals, increased adipose tissue promotes local activation of the RAS, leading to heightened angiotensin II (Ang II) activity, oxidative stress, inflammation, and impaired lipid metabolism. These pathological mechanisms contribute to both elevated blood pressure and abnormal lipid profiles. Targeting the RAS through angiotensin-converting enzyme (ACE) inhibitors, angiotensin II receptor blockers (ARBs), and novel agents offers therapeutic potential in reducing obesity-associated hypertension and hyperlipidemia. This review discusses the molecular mechanisms linking obesity to RAS overactivation, examines current pharmacological strategies, and explores emerging therapeutic options aimed at modulating the RAS in the context of obesity-driven cardiometabolic disorders. Keywords: Renin-angiotensin system, obesity, hyperlipidemia, hypertension, angiotensin II, ACE inhibitors, ARBs, metabolic syndrome, cardiovascular disease.

Effect of the renin-angiotensin-aldosterone system inhibitors on time to nucleic acid negative conversion in hypertensive patients with SARS-CoV-2 omicron infection: a propensity score matching study.

We examined the relationship between RAAS inhibitor use and Omicron infection in mildly symptomatic patients. This retrospective case-control observational study included 50,121 patients with mild Omicron infection from the largest "Fangcang" shelter hospital in Shanghai between April 9, 2022, and May 21, 2022. Using 1:1 propensity score matching (PSM), we classified 4394 COVID-19 patients into hypertension and non-hypertension groups, and 406 hypertensive patients into RAAS inhibitor and non-RAAS inhibitor groups. The risk of initial symptoms of infection, cumulative negative conversion rates, time to nucleic-acid negative conversion, and viral loads were compared. In the hypertension group, the median number of days for nucleic-acid negative conversion was 7.0 (IQR, 5.0-9.0), which was greater than non-hypertensive group (median (IQR) 6.0 (4.0-8.0), P < 0.001, Cohen's d = 0.29); the mean and minimum cycle threshold values (CT-values) were significantly lower (P < 0.001, Cohen's d = 0.23). In the RAAS inhibitors group, the median number of days for nucleic-acid negative conversion was 7.0 days (IQR, 5.0-9.0), which was shorter than the non-RAAS inhibitors group ([median (IQR)] 8.0 (6.0-10.0), P < 0.001, Cohen's d = 0.34), the cumulative negative conversion rates at 3-8 days being all higher than non-RAAS inhibitors groups (P < 0.05). The most significant difference in negative conversion rate between the RAAS inhibitor and non-RAAS inhibitor group was on the 4th day. No significant difference was observed in mean and minimum CT-values from RAAS inhibitor and non-RAAS inhibitor groups (P > 0.05). RAAS inhibitor use in patients with hypertension is associated with nucleic-acid negative conversion duration and negative conversion rate. RAAS inhibitors clearly do not aggravate or prolong COVID-19.

Calcitriol prevents SARS-CoV spike-induced inflammation in human trophoblasts through downregulating ACE2 and TMPRSS2 expression

SARS-CoV-2, the causative virus of COVID-19, increases the risk of pregnancy complications including hypertensive disorders and placental inflammation. The spike glycoprotein mediates viral cell entry by interacting with the angiotensin-converting enzyme (ACE)2 in conjunction with the transmembrane serine protease 2 (TMPRSS2). ACE1, ACE2 and renin are components of the renin-angiotensin system (RAS), which regulates blood pressure. As the placenta expresses all these proteins, it is a target for SARS-CoV-2 and a source of blood pressure modulators. Noteworthy, an ACE1/ACE2 ratio imbalance can lead to RAS dysregulation and a bad prognosis in COVID-19 patients. Calcitriol, the most active vitamin D metabolite, negatively regulates RAS, reduces inflammation, and enhances antiviral immunity, thereby protecting against COVID-19 severity. However, contrasting information exists on the regulatory role of calcitriol upon RAS components and SARS-CoV-2 receptors; while the impact of calcitriol on spike-induced inflammation in placental cells has not been explored. Thus, we studied the effects of calcitriol on these parameters using the trophoblast cell line HTR-8/SVneo and primary syncytiotrophoblasts. By RT-qPCR, ELISA, and immunocytochemistry, we found that the spike enhanced proinflammatory cytokines expression and secretion, while calcitriol significantly downregulated this effect. Calcitriol also diminished ACE1, ACE2, TMPRSS2, and renin gene expression, as well as ACE1/ACE2 mRNA ratio. ConclusionsIn the human placenta, calcitriol reduced the gene expression of main RAS components and TMPRSS2, resulting in the inhibition of spike-induced inflammation. This outcome suggest that vitamin D participates in restricting SARS-CoV-2 placental infection by rendering trophoblasts less permissive to infection while helping to regulate maternal blood pressure and decreasing inflammation.

Pathophysiology of vascular ageing and the effect of novel cardio-renal protective medications in preventing progression of chronic kidney disease in people living with diabetes.

Among people with diabetes those with chronic kidney disease (CKD) have a reduced life expectancy with increased risk of cardiovascular disease (CVD) a major contributor to morbidity and mortality. CKD related to diabetes is growing worldwide and is one of the leading causes of kidney failure globally. Diabetes is associated with accelerated vascular ageing and the related mechanisms and mediators that drive the progression of CKD and CVD disease in people with diabetes may help provide insights into the pathophysiology of cardio-renal complications and guide treatment interventions in people with diabetes. We conducted a narrative review of the literature using PubMed for English language articles that contained keywords that related to diabetes, chronic or diabetic kidney disease, ageing, cellular senescence, arterial stiffness, Klotho and sirtuins, sodium-glucose co-transporter-2 (SGLT-2) inhibitors, renin angiotensin aldosterone system (RAAS) and glucagon-like peptide-1 (GLP-1) receptor agonists. Progressive kidney disease in diabetes is associated with accelerated ageing driven in part by multiple processes such as cellular senescence, inflammation, oxidative stress and circulating uremic toxins. This accelerated ageing phenotype contributes to increased arterial stiffness, endothelial dysfunction, cognitive decline and muscle wasting, thereby elevating morbidity and mortality in individuals with diabetes and CKD. Deficiency of the kidney-derived anti-ageing hormone Klotho and reduced sirtuin levels play pivotal roles in these ageing pathways. Dietary, lifestyle and pharmacological interventions targeting vascular ageing may help reduce the progression of CKD and associated CVD in people with diabetes. The current standard of care and pillars of treatment for kidney disease such as RAAS inhibitors, SGLT-2 inhibitors and GLP-1 receptor agonists all influence pathways involved in vascular ageing. A multifactorial intervention to prevent the development of CKD by targeting traditional risk factors as well as treatment with novel agents with cardio-renal beneficial effects can prevent accelerated ageing and extend lifespan in people with diabetes.