Search Results (1,583)

SARS-CoV-2 has an affinity for binding to the human Angiotensin-converting enzyme 2 (ACE2) receptor through cleavage and conformational changes at the S1–S2 boundary and the receptor binding domain of the spike protein, which is also the most variable part of SARS-CoV-2. This study aimed to investigate the expression of Angiotensin-converting enzyme 2 (ACE2), spike protein, and CD68+ markers in placental tissue to demonstrate a possible correlation with the level of systemic oxidative stress biomarkers in patients who were infected with SARS-CoV-2 during pregnancy. A prospective clinical cohort study was designed to investigate the presence of CD68+ macrophages, ACE2, and spike proteins in placental tissue using immunohistochemical methods and to compare these results with oxidative stress from our previous study. Spike and CD68+ macrophages’ immunoreactivity were more pronounced in the placental tissue of patients from the SARS-CoV-2 group. Placental tissue spike protein and CD68+ immunoreactivity correlate with maternal and fetal Thiobarbituric Acid Reactive (TBARS) levels. This study has confirmed that spike protein expression in placental tissue is associated with the newborn’s stay in intensive neonatal care. Therefore, immunoreactivity analysis for the Spike antigen is important in detecting newborns at risk of early neonatal complications. Full article

Cardiovascular disease (CVD) is the leading cause of death worldwide, with pathophysiological mechanisms often involving platelet activation and chronic inflammation. While antiplatelet agents targeting adenosine diphosphate (ADP)-mediated pathways are well established in CVD management, less is known about drug interactions with the platelet-activating factor (PAF) pathway, a key mediator of inflammation. This study aimed to evaluate the effects of several commonly used cardiovascular and anti-inflammatory drug classes—including clopidogrel, non-steroidal anti-inflammatory drugs (NSAIDs), angiotensin II receptor blockers (ARBs), β-blockers, and analgesics—on platelet function via both the ADP and PAF pathways. Using human platelet-rich plasma (hPRP) from healthy donors, we assessed platelet aggregation in response to these two agonists in the absence and presence of graded concentrations of each of these drugs or of their usually prescribed combinations. The study identified differential drug effects on platelet aggregation, with some agents showing pathway-specific activity. Clopidogrel and NSAIDs demonstrated expected antiplatelet effects, while some (not all) antihypertensives exhibited additional anti-inflammatory potential. These findings highlight the relevance of evaluating pharmacological activity beyond traditional targets, particularly in relation to PAF-mediated inflammation and thrombosis. This dual-pathway analysis may contribute to a broader understanding of drug mechanisms and inform the development of more comprehensive therapeutic strategies for the prevention and treatment of cardiovascular, hypertension, and inflammation-driven diseases. Full article

The pivotal role of angiotensin II (AngII) in cardiovascular disease has been firmly established, as evidenced by a robust body of literature and the broad clinical application of AngII-inhibiting therapies. AngII type 1 receptor is the primary mediator of AngII action, and its activation initiates a multitude of cellular responses that contribute to the development of hypertension, structural changes in the heart and vasculature, and damage to target organs. This review examines AngII from a different perspective, exploring the link between the renin–angiotensin–aldosterone system and cardiovascular risk beyond hypertension, with particular emphasis on atherosclerosis development and progression. Full article

Background: Acute kidney injury (AKI) frequently occurs following major liver resection, adversely affecting both short- and long-term outcomes. This study aimed to determine the incidence of AKI post-hepatectomy and identify relevant pre- and intraoperative risk factors. Our secondary objectives were to develop a predictive score for postoperative AKI and assess the associations between AKI, chronic kidney disease (CKD), and 1-year mortality. Methods: This was a retrospective study in a cancer referral center in Marseille, France, from 2018 to 2022. Results: Among 169 patients, 55 (32.5%) experienced AKI. Multivariate analysis revealed several independent risk factors for postoperative AKI, including age, body mass index, the use of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, time to liver resection, intraoperative shock, and bile duct reconstruction. Neoadjuvant chemotherapy was protective. The AKIMEBO score was developed, with a threshold of ≥15.6, demonstrating a sensitivity of 89.5%, specificity of 76.4%, positive predictive value of 61.8%, and negative predictive value of 94.4%. AKI was associated with increased postoperative morbidity and one-year mortality following major hepatectomy. Conclusion: AKI is a common complication post-hepatectomy. Factors such as time to liver resection and intraoperative shock management present potential clinical intervention points. The AKIMEBO score can provide a valuable tool for postoperative risk stratification. Full article

Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is the etiologic agent that causes the coronavirus disease (COVID-19) identified in Wuhan, in 2019. Men are more prone to developing severe manifestations than women, suggesting a possible crucial role of sex hormones. 17,β-Estradiol (E2) and 1,25 α dihydroxyvitamin D₃ (calcitriol) act upon gene pathways as immunomodulators in several infectious respiratory diseases. In this study, we aimed to evaluate the influence of E2 and calcitriol on the VSV-based pseudovirus SARS-CoV-2 and SARS-CoV-2 infection in vitro. We infected Vero E6 cells with the recombinant VSV-based pseudovirus SARS-CoV-2 and the SARS-CoV-2 viruses according to the pre-treatment and pre–post-treatment models. The Angiotensin-Converting Enzyme 2 (ACE2) and Vitamin D Receptor (VDR) gene expression did not change under different treatments. The VSV-based pseudovirus SARS-CoV-2 infection showed a significant decrease in the focus-forming unit count in the presence of E2 and calcitriol (either alone or in combination) in the pre-treatment model, while in the pre–post-treatment model, the infection was inhibited only in the presence of E2. Th SARS-CoV-2 infection highlighted a decrease in viral titres in the presence of E2 and calcitriol only in the pre–post-treatment model. 17,β-Estradiol and calcitriol can exert an inhibitory effect on SARS-CoV-2 infections, demonstrating their protective role against viral infections. Full article

Diabetic nephropathy affects approximately 30–40% of individuals with diabetes mellitus (DM) and is a major contributor to end-stage renal disease (ESRD). While angiotensin II receptor blockers (ARBs) have long served as a standard treatment, sodium-glucose cotransporter-2 inhibitors (SGLT2i) have recently gained attention for their renal and cardiovascular benefits. However, comparative real-world data on their long-term renal effectiveness remain limited. We conducted a retrospective, longitudinal study over a 2-year period to compare the impact of ARB monotherapy versus SGLT2i and angiotensin-converting enzyme inhibitor (ACEi) combination therapy on the progression of chronic kidney disease (CKD) in patients with DM. A total of 126 patients were included and grouped based on treatment regimen. Renal biomarkers were analyzed using t-tests and ANOVA (p < 0.01). Albuminuria was qualitatively classified via urinalysis as negative, level 1 (+1), level 2 (+2), or level 3 (+3). The ARB group demonstrated higher estimated glomerular filtration rate (eGFR) and lower serum creatinine (sCr) levels than the combination therapy group, with glycated hemoglobin (HbA1c), potassium (K⁺), and blood pressure remaining within normal limits in both cohorts. Albuminuria remained stable over time, with 60.8% of ARB users and 73.1% of combination therapy users exhibiting persistently or on-average negative results. Despite the expected additive benefits of SGLT2i/ACEi therapy, ARB monotherapy was associated with slightly more favorable renal function markers and a lower incidence of severe albuminuria. These findings suggest a need for further controlled studies to clarify the comparative long-term renal effects of these treatment regimens. Full article

Heart failure with preserved ejection fraction (HFpEF) is a heterogeneous syndrome with increasing prevalence and substantial morbidity and mortality. Recent advances in pharmacotherapy have transformed its management. This review summarizes current evidence supporting the use of sodium–glucose cotransporter 2 inhibitors, non-steroidal mineralocorticoid receptor antagonists, and glucagon-like peptide-1 receptor agonists, alongside selected use of angiotensin receptor–neprilysin inhibitors. Emphasis is placed on early initiation of disease-modifying therapies, phenotypic tailoring, and comorbidity-targeted strategies, especially in obese and diabetic patients. Together, these approaches define a new era of guideline-directed, personalized care for patients with HFpEF. Full article

Background/Objectives: Guidelines recommend patients with heart failure with reduced ejection fraction (HFrEF) receive four-pillar heart failure (4P-HF) therapy, which significantly reduces cardiac morbidity and mortality. However, implementing these guidelines effectively into clinical practice remains challenging. Methods: Patients with HFrEF on submaximal 4P-HF therapy were identified from a large, multicentre Cardiology network database using a natural language processing tool, supported by manual file review. A nurse-led, remotely delivered, medication uptitration program aimed to optimise therapy in this real-world cohort. Results: The final cohort included 2004 patients with a mean age of 72.7 ± 11.6 years. Utilisation of 4P-HF increased from 11.1% at baseline to 49.8% post intervention, and each individual medication class increased significantly post intervention (all p < 0.001). The largest increase was observed with the use of sodium–glucose cotransporter 2 inhibitors, which rose from 17.3% to 73.9%, followed by mineralocorticoid receptor antagonists (51.6% to 65.7%), beta-blockers (88.4% to 97.0%), and angiotensin-converting enzyme inhibitors/angiotensin receptor blockers/angiotensin receptor blocker–neprilysin inhibitors (89.8% to 96.4%). In patients on submaximal therapy, barriers were documented in all cases. Following medication optimisation, left ventricular ejection function (LVEF) improved significantly (38.5% ± 10.8% vs. 42.5% ± 11.7, p < 0.001). Conclusions: This nurse-led, remotely delivered, medication optimisation program significantly improved the adoption of 4P-HF therapy and LVEF in patients with HFrEF. The program demonstrates a practical, scalable solution for the optimisation of HFrEF therapy across a large healthcare network. Full article

Background/Objectives: Real-world evidence shows alarmingly suboptimal utilization of guideline directed medical therapy (GDMT) in heart failure with reduced ejection fraction (HFrEF). One of the barriers of GDMT implementation appears to be concerns about the potential development of drug-related adverse events (AEs), particularly in high-risk patients. This study aimed to evaluate whether advanced HFrEF (AHF) patients can be up-titrated safely and whether AHF predisposes individuals to the occurrence of putatively drug-related AEs. Methods: A total of 373 HFrEF patients with documented baseline, 2 months, and 12 months visits were analyzed for utilization and target dosages (TDs) of HF drugs. Successful up-titration and AEs were evaluated for different stages of HF reflected by N-terminal pro-B type natriuretic peptide (NT-proBNP) (<1000 pg/mL, 1000–2000 pg/mL, >2000 pg/mL). Results: A stepwise increase in HF medications was observed for all drug classes during follow-up. At 12 months, 73%, 75%, 62%, 86%, and 45% of patients received ≥90% of TDs of beta-blockers (BBs), renin–angiotensin system inhibitors (RASis), mineralocorticoid receptor antagonists (MRAs), sodium–glucose cotransporter-2 inhibitors (SGLT2 i), and triple-therapy, respectively. Predictors of successful up-titration in logistic regression were baseline HF drug TDs, estimated glomerular filtration rate (eGFR), and potassium, but not NT-proBNP or age. The development of AEs was rare, with hyperkalemia as the most common event (34% at 12 months). AEs were comparable in all stages of HF. However, the development of hyperkalemia was more frequent in patients with higher NT-proBNP and also accounted for most cases of incomplete up-titration. Conclusions: This study suggests that with dedicated protocols and frequent visits, GDMT can be successfully implemented across all stages of HFrEF, including patients with AHF. Full article

Background: Cerebral aneurysm (CA) is a focal or diffuse pathological dilation of the cerebral arterial wall that arises due to various etiological factors. It represents a serious vascular condition, particularly affecting the elderly, and carries a high risk of rupture and neurological morbidity. Clonidine (CL), an α2-adrenergic receptor agonist, has been reported to suppress aneurysm progression; however, its underlying molecular mechanisms, especially in relation to cerebral endothelial dysfunction, remain unclear. This study aimed to investigate the potential of CL to mitigate CA development by modulating apoptosis, inflammation, and oxidative stress in an Angiotensin II (Ang II)-induced endothelial injury model. Methods: Human brain microvascular endothelial cells (HBMECs) were used to establish an in vitro model of endothelial dysfunction by treating cells with 1 µM Ang II for 48 h. CL was administered 2 h prior to Ang II exposure at concentrations of 0.1, 1, and 10 µM. Cell viability was assessed using the MTT assay. Oxidative stress markers, including reactive oxygen species (ROS) and Nitric Oxide (NO), were measured using 2′,7′–dichlorofluorescin diacetate (DCFDA). Gene expression levels of vascular endothelial growth factor (VEGF), matrix metalloproteinases (MMP-2 and MMP-9), high mobility group box 1 (HMGB1), and nuclear factor kappa B (NF-κB) were quantified using RT-qPCR. Levels of proinflammatory cytokines; tumor necrosis factor-alpha (TNF-α), Interleukin-6 (IL-6), and interferon-gamma (IFN-γ); were measured using commercial ELISA kits. Results: Ang II significantly increased ROS production and reduced NO levels, accompanied by heightened proinflammatory cytokine release and endothelial dysfunction. MTT assay revealed a marked decrease in cell viability following Ang II treatment (34.18%), whereas CL preserved cell viability in a concentration-dependent manner: 44.24% at 0.1 µM, 66.56% at 1 µM, and 81.74% at 10 µM. CL treatment also significantly attenuated ROS generation and inflammatory cytokine levels (p < 0.05). Furthermore, the expression of VEGF, HMGB1, NF-κB, MMP-2, and MMP-9 was significantly downregulated in response to CL. Conclusions: CL exerts a protective effect on endothelial cells by reducing oxidative stress and suppressing proinflammatory signaling pathways in Ang II-induced injury. These results support the potential of CL to mitigate endothelial injury in vitro, though further in vivo studies are required to confirm its translational relevance. Full article

The synthesis and structural characterization of three new triple-stranded helical complexes ([Dy₂(L²)₃]2Cl∙15H₂O (C1), [Y₂(L²)₃]3(NO₃)Cl∙14H₂O∙DMSO (C2), and [Eu₂(L⁴)₃]∙12H₂O (C3), where L² and L⁴ are ligands derived from pyridoxal hydrochloride and succinic or adipic acid dihydrazides, respectively, were described. The X-ray data, combined with spectroscopic measurements, indicated that L² and L⁴ act as bis-tridentate ligands, presenting two tridentate chelating cavities O,N,O to obtain the dinuclear complexes C1–C3. Their antiviral profile was predicted via in silico calculations in terms of interaction with the structural severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike glycoprotein in the down- and up-states and complexed with the cellular receptor angiotensin-converting enzyme 2 (ACE2). The best affinity energy values (−9.506, −9.348, and −9.170 kJ/mol for C1, C2, and C3, respectively) were obtained for the inorganic complexes docked in the model spike-ACE2, with C1 being suggested as the most promising candidate for a future in vitro validation. The obtained in silico antiviral trend was supported by the prediction of the electronic and physical–chemical properties of the inorganic complexes via the density functional theory (DFT) approach, representing an original and relevant contribution to the bioinorganic and medicinal chemistry fields. Full article

The renin–angiotensin–aldosterone system (RAAS) plays a central role in cardiovascular and renal homeostasis and is increasingly recognized for its broad immunomodulatory effects. Pharmacological RAAS inhibition, primarily via angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs), has demonstrated therapeutic value beyond its use in hypertension and heart failure, extending to autoimmune, infectious, oncologic, and neurodegenerative conditions. ACEIs and ARBs modulate both innate and adaptive immune responses through Ang II-dependent and -independent mechanisms, influencing macrophage polarization, T-cell differentiation, cytokine expression, and antigen presentation. Notably, ACEIs exhibit Ang II-independent effects by enhancing antigen processing and regulating amyloid-β metabolism, offering potential neuroprotective benefits in Alzheimer’s disease. ARBs, particularly telmisartan and candesartan, provide additional anti-inflammatory effects via PPARγ activation. In cancer, RAAS inhibition affects tumor growth, angiogenesis, and immune surveillance, with ACEIs and ARBs showing distinct yet complementary impacts on tumor microenvironment modulation and chemotherapy cardioprotection. Moreover, ACEIs have shown promise in autoimmune myocarditis, colitis, and diabetic nephropathy by attenuating inflammatory cytokines. While clinical evidence supports the use of centrally acting ACEIs to treat early cognitive decline, further investigation is warranted to determine the long-term outcomes across disease contexts. These findings highlight the evolving role of RAAS inhibitors as immunomodulatory agents with promising implications across multiple systemic pathologies. Full article

Aminopeptidase A (APA) cleaves a single aspartate residue from the amino terminus of peptides within the renin angiotensin system (RAS). Since several RAS peptides contain an N-terminal aspartate, we developed an assay to evaluate the effect of recombinant APA on the cleavage of Ang I, Ang II, Ang-(1-7), Ang-(1-9), and Ang-(1-12). The latter peptide has been proposed to be a functional Ang II-forming substrate with a hypertensive action attributable to the formed Ang II acting on AT1 receptors. Here we investigated the following: (a) the hydrolytic action of APA on Ang-(1-12), Ang I (1-10), Ang-(1-9), Ang II and Ang-(1-7) and (b) whether Ang-(1-12) pressor activity is altered by recombinant APA (r-APA) or genetic APA deficiency. We found that (a) r-APA cleaves the N-terminal aspartate of not only Ang II but also [Ang-(1-12), Ang I (1-10), Ang-(1-9)] and [Ang-(1-7)]; (b) the pressor activity of Ang-(1-12) was abolished in the presence of Lisinopril or Telmisartan; (c) r-APA significantly attenuated the pressor activities of infused Ang I and Ang II but not Ang-(1-12); and (d) r-ACE2 also did not attenuate the pressor effect of infused Ang-(1-12). Thus, in addition to increasing blood pressure indirectly via the formation of Ang II, Ang-(1-12) increases blood pressure by an Ang II-independent mechanism. We conclude that APA has an antihypertensive effect attributable to rapid degradation of Ang II, and this action may have a therapeutic potential in forms of hypertension that are Ang II-dependent. In addition, APA metabolizes Ang-(1-12), a peptide that has a prohypertensive action, in part, as a source of Ang II formation but also by a yet to be determined action independent of Ang II. Full article

Background/Objectives: Hypertension is a pathological condition characterized by elevated systolic and/or diastolic blood pressure. A range of pharmacotherapeutic agents are available to treat this condition and prevent complications, including the angiotensin II AT1-receptor blocker losartan. Following oral administration, losartan is exposed to a variety of enzymes that facilitate its metabolism or transportation. The structural characteristics of the genes that encode the enzymes may potentially impact the pharmacokinetics and pharmacodynamics of losartan, thereby modulating its effects on the treatment process. Methods: In this study, a computational model of losartan pharmacokinetics was developed, taking into account the influence of different alleles of the CYP2C9 gene, which plays a pivotal role in losartan metabolism, and the ABCB1 gene, which is responsible for losartan transport. Results: Alterations in the modeled activities of the enzymes encoded by CYP2C9 and ABCB1 result in changes in the losartan and its metabolite profiles that are consistent with known experimental data in real patients with different CYP2C9 and ABCB1 genotypes. Conclusions: The findings of the modeling can potentially be used to personalize drug therapy for arterial hypertension. Full article

The renin–angiotensin system (RAS) plays a central role in cardiovascular regulation and has gained prominence in the pathogenesis of Coronavirus Disease 2019 (COVID-19) due to the critical function of angiotensin-converting enzyme 2 (ACE2) as the entry receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Angiotensin IV, but not angiotensin II, has recently been reported to enhance the binding between the viral spike protein and ACE2. To investigate the virological significance of this effect, we developed a single-round infection assay using SARS-CoV-2 viral-like particles expressing the spike protein. Our results demonstrate that while angiotensin II does not affect viral infectivity across concentrations ranging from 40 nM to 400 nM, angiotensin IV enhances viral entry at a low concentration but exhibits dose-dependent inhibition at higher concentrations. These findings highlight the unique dual role of angiotensin IV in modulating SARS-CoV-2 entry. In silico molecular docking simulations indicate that angiotensin IV was predicted to associate with the S1 domain near the receptor-binding domain in the open spike conformation. Given that reported plasma concentrations of angiotensin IV range widely from 17 pM to 81 nM, these levels may be sufficient to promote, rather than inhibit, SARS-CoV-2 infection. This study identifies a novel link between RAS-derived peptides and SARS-CoV-2 infectivity, offering new insights into COVID-19 pathophysiology and informing potential therapeutic strategies. Full article