Renin-Angiotensin-Aldosterone System: From History to Practice of a Secular Topic.

Renin-angiotensin-aldosterone system (RAAS) inhibitors are standard care in patients with hypertension, heart failure or chronic kidney disease (CKD). Although we have studied the RAAS for decades, there are still circumstances that remain unclear. In this review, we describe the evolution of the RAAS and pose the question of whether this survival trait is still necessary to humankind in the present age. We elucidate the benefits on cardiovascular health and kidney disease of RAAS inhibition and present promising novel medications. Furthermore, we address why more studies are needed to establish a new standard of care away from generally prescribing ACEi or ARB toward an improved approach to combine drugs tailored to the needs of individual patients.

The role of the brain renin-angiotensin system in Parkinson´s disease.

The renin-angiotensin system (RAS) was classically considered a circulating hormonal system that regulates blood pressure. However, different tissues and organs, including the brain, have a local paracrine RAS. Mutual regulation between the dopaminergic system and RAS has been observed in several tissues. Dysregulation of these interactions leads to renal and cardiovascular diseases, as well as progression of dopaminergic neuron degeneration in a major brain center of dopamine/angiotensin interaction such as the nigrostriatal system. A decrease in the dopaminergic function induces upregulation of the angiotensin type-1 (AT1) receptor activity, leading to recovery of dopamine levels. However, AT1 receptor overactivity in dopaminergic neurons and microglial cells upregulates the cellular NADPH-oxidase-superoxide axis and Ca2+ release, which mediate several key events in oxidative stress, neuroinflammation, and α-synuclein aggregation, involved in Parkinson's disease (PD) pathogenesis. An intraneuronal antioxidative/anti-inflammatory RAS counteracts the effects of the pro-oxidative AT1 receptor overactivity. Consistent with this, an imbalance in RAS activity towards the pro-oxidative/pro-inflammatory AT1 receptor axis has been observed in the substantia nigra and striatum of several animal models of high vulnerability to dopaminergic degeneration. Interestingly, autoantibodies against angiotensin-converting enzyme 2 and AT1 receptors are increased in PD models and PD patients and contribute to blood-brain barrier (BBB) dysregulation and nigrostriatal pro-inflammatory RAS upregulation. Therapeutic strategies addressed to the modulation of brain RAS, by AT1 receptor blockers (ARBs) and/or activation of the antioxidative axis (AT2, Mas receptors), may be neuroprotective for individuals with a high risk of developing PD or in prodromal stages of PD to reduce progression of the disease.

Recent Advances in the Management of Diabetic Kidney Disease: Slowing Progression.

Diabetic kidney disease (DKD) is a major cause of chronic kidney disease (CKD), and it heightens the risk of cardiovascular incidents. The pathogenesis of DKD is thought to involve hemodynamic, inflammatory, and metabolic factors that converge on the fibrotic pathway. Genetic predisposition and unhealthy lifestyle practices both play a significant role in the development and progression of DKD. In spite of the recent emergence of angiotensin receptors blockers (ARBs)/angiotensin converting enzyme inhibitor (ACEI), sodium-glucose cotransporter 2 (SGLT2) inhibitors, and nonsteroidal mineralocorticoid receptors antagonists (NS-MRAs), current therapies still fail to effectively arrest the progression of DKD. Glucagon-like peptide 1 receptor agonists (GLP-1RAs), a promising class of agents, possess the potential to act as renal protectors, effectively slowing the progression of DKD. Other agents, including pentoxifylline (PTF), selonsertib, and baricitinib hold great promise as potential therapies for DKD due to their anti-inflammatory and antifibrotic properties. Multidisciplinary treatment, encompassing lifestyle modifications and drug therapy, can effectively decelerate the progression of DKD. Based on the treatment of heart failure, it is recommended to use multiple drugs in combination rather than a single-use drug for the treatment of DKD. Unearthing the mechanisms underlying DKD is urgent to optimize the management of DKD. Inflammatory and fibrotic factors (including IL-1, MCP-1, MMP-9, CTGF, TNF-a and TGF-ß1), along with lncRNAs, not only serve as diagnostic biomarkers, but also hold promise as therapeutic targets. In this review, we delve into the potential mechanisms and the current therapies of DKD. We also explore the additional value of combing these therapies to develop novel treatment strategies. Drawing from the current understanding of DKD pathogenesis, we propose HIF inhibitors, AGE inhibitors, and epigenetic modifications as promising therapeutic targets for the future.

Pressure control and treatment interact in the deterioration of incidental visuospatial memory in hypertensive patients.

BACKGROUND: Systemic hypertension (SH) is the main risk factor to cognitive deterioration, whereas visuospatial memory is more vulnerable to ageing. Some antihypertensive agents have a neuroprotector effect, however, such effects could be masked by comorbidities and/or the lack of effective control on the arterial pressure of patients. OBJECTIVE: To assess this, the evaluation of incidental visuospatial memory of SH patients and the relation to the treatment received and the effective control of pressure were made. METHOD: 80 patients (46 woman) were included grouped by the received medication: angiotensin 2 receptor blockers (ARB) or angiotensin converting enzyme inhibitors (ACEI). A multiple correlation analysis between visuospatial scores and clinical variables was made; also, a mixed model analysis (fixed factors: treatment, pressure control, diabetes comorbidity; aleatory factors: age, schooling, months from SH diagnoses). RESULTS: Half of the patients had a controlled pressure, from them the higher proportion received ARB, and a minor number of patients received ACEI. The normotensive patients receiving ACEI were inefficient whereas the hypertensive patients were more efficient. The systolic pressure was negatively related with the visuospatial scores in spite of no correlations occurred with MoCA and Raven tests. CONCLUSIONS: The visuospatial incidental/intentional scores were negatively correlated with systolic pressure. The efficiency in the visuospatial ability depends on the interaction of treatment and effective control of blood pressure. The interaction between treatment and effective pressure control must be taken in count when cognitive deterioration is studied.

ANTECEDENTES: La hipertensión arterial sistémica (HAS) es el principal factor de riesgo para el deterioro cognitivo; por otro lado, la memoria visuoespacial es más vulnerable al envejecimiento. Algunos fármacos antihipertensivos tienen un efecto neuroprotector, pero tal efecto puede enmascararse o bien no manifestarse por comorbilidad o por falta de control efectivo de la presión arterial. OBJETIVO: Evaluar las alteraciones en la memoria visuoespacial incidental de pacientes con HAS en relación con su tratamiento antihipertensivo y su control de la presión. MÉTODO: Se incluyeron 80 pacientes con HAS (46 mujeres), agrupados por su medicación en bloqueadores de los receptores de la angiotensina II (BRA) o inhibidores de la enzima convertidora de angiotensina (IECA). Se realizó un análisis de correlaciones múltiples para los puntajes obtenidos en la prueba de memoria visuoespacial incidental/intencional y un análisis de modelos mixtos (factores fijos: tratamiento, control de la presión y comorbilidad con diabetes; factores aleatorios: edad, escolaridad, meses desde el diagnóstico de HAS y coeficiente intelectual). RESULTADOS: De los pacientes controlados, la mayoría de los que recibían BRA fueron eficientes y los que recibían IECA fueron deficientes. De los que recibían IECA, los descontrolados hipertensos fueron más eficientes que los normotensos. La memoria visuoespacial se correlacionó negativamente con la presión sistólica a pesar de no haber diferencias en MoCA y Raven. CONCLUSIONES: La eficiencia en la memoria visuoespacial dependió de la interacción del tratamiento y el control de la presión. Ambos factores, tratamiento y control efectivo de la presión, deben considerarse en la evaluación del deterioro cognitivo asociado a la HAS.

Sacubitril/Valsartan in Patients Hospitalized With Decompensated Heart Failure.

BACKGROUND: The efficacy and safety of sacubitril/valsartan in patients hospitalized with heart failure (HF) across the spectrum of left ventricular ejection fraction (EF) has not been described. OBJECTIVES: Data from randomized trials of sacubitril/valsartan in HF patients with EF ≤40% (PIONEER-HF [Comparison of Sacubitril/Valsartan Versus Enalapril on Effect of NT-proBNP in Patients Stabilized From an Acute Heart Failure Episode] trial) and >40% (PARAGLIDE-HF [Prospective comparison of ARNI with ARB Given following stabiLization In DEcompensated HFpEF] trial) following recent worsening heart failure (WHF) were pooled to examine treatment effect across the EF spectrum. METHODS: The PIONEER-HF and PARAGLIDE-HF trials were double-blind, randomized trials of sacubitril/valsartan vs control therapy (enalapril or valsartan, respectively). All participants in the PIONEER-HF trial and 69.5% in the PARAGLIDE-HF trial were enrolled during hospitalization for HF after stabilization. The remainder in the PARAGLIDE-HF trial were enrolled ≤30 days after a WHF event. The primary endpoint of both trials was time-averaged proportional change in N-terminal pro-B-type natriuretic peptide (NT-proBNP) from baseline through weeks 4 and 8. Adjudicated clinical endpoints were analyzed through the end of follow-up, adjusting for trial. RESULTS: The pooled analysis included 1,347 patients (881 from PIONEER-HF, 466 from PARAGLIDE-HF). Baseline characteristics included median age 66 years, 36% women, 31% Black, 34% de novo HF, and median EF 30%. The reduction in NT-proBNP was 24% greater with sacubitril/valsartan vs control therapy (n = 1,130; ratio of change = 0.76; 95% CI: 0.69-0.83; P < 0.0001). Cardiovascular death or hospitalization for HF was reduced by 30% with sacubitril/valsartan vs control therapy (HR: 0.70; 95% CI: 0.54-0.91; P = 0.0077). This effect was consistent across the spectrum of EF ≤60%. Sacubitril/valsartan increased symptomatic hypotension (risk ratio: 1.35; 95% CI: 1.05-1.72). CONCLUSIONS: In patients stabilized after WHF, sacubitril/valsartan led to a greater reduction in plasma NT-proBNP and improved clinical outcome compared with control therapy, in particular across the spectrum of EF ≤60%. (Comparison of Sacubitril/Valsartan Versus Enalapril on Effect of NT-proBNP in Patients Stabilized From an Acute Heart Failure Episode [PIONEER-HF]; NCT02554890; Changes in NT-proBNP, Safety, and Tolerability in HFpEF Patients With a WHF Event [HFpEF Decompensation] Who Have Been Stabilized and Initiated at the Time of or Within 30 Days Post-decompensation [PARAGLIDE-HF]; NCT03988634).

A simple tandem bioassay-guided SCX-RP SPE fractionation for efficient active peptide screening from Inca nut cake protein hydrolysate.

Typically, bioactive peptides were uncovered from complex hydrolysates using sequential bioassay-guided fractionation. To increase the efficiency of bioactive peptide screening, a simple and convenient tandem bioassay-guided fractionation based on solid-phase extraction (SPE) was conducted to screen the angiotensin-I-converting enzyme (ACE) inhibitory peptides from the hydrolysate of Inca nut cake protein (INCP). The so-called SCX-RP SPE system was constructed by assembling SCX (strong cation exchange) and RP (reversed phase) SPE cartridges. Using this tandem SCX-RP SPE, the INCP digested with combined gastrointestinal protease (INCP GP) was fractionated into 30 fractions. The fraction F11 exhibited the highest ACE inhibitory activity among 30 fractions. The ACE IC50 of fraction F11 was calculated to be 6.6 ± 0.5 µg/mL. The ACEI activity of fraction F11 was stronger than the INCP GP hydrolysate (ACE IC50 of 12.7 ± 0.4 µg/mL). The tandem SCX-RP SPE fractionation reduced the number of ACE inhibitory (ACEI) peptide candidates from 127 peptides in the INCP GP hydrolysate to only ten peptides in fraction F11. Subsequently, WALPTQSW (WW-8) and WLPTKSW (WW-7) from fraction F11 were synthesized, and their ACE IC50 was determined to be 4.7 ± 0.1 and 7.9 ± 0.1 µM, respectively. The dipeptidyl peptidase-4 (DPP4) inhibitory and 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activities of WALPTQSW (WW-8) were also explored to give IC50 values of 131.7 ± 5.2 and 191.8 ± 7.0 µM, respectively. The molecular docking and inhibition mechanism studies indicated that WW-8 inhibited ACE and DPP4 as competitive and non-competitive inhibitors, respectively. The pre-incubation experiment of WW-8 toward ACE and DPP4 demonstrated that WW-8 was a true-inhibitor type. Additionally, the amount of WW-8 was quantified to be 5.8 ± 0.2 and 35 ± 0.4 µg per milligram hydrolysate and fraction F11, respectively. This study demonstrated tandem bioassay-guided SCX-RP SPE fractionation efficiently screened ACEI peptide derived from INCP GP hydrolysate, adding more value to Inca nut cake (a leftover of the oil industry) as a bioactive peptide precursor.

Concurrent exercise training potentiates the effects of angiotensin-converting enzyme inhibitor on regulatory systems of blood pressure control in ovariectomized hypertensive rats.

OBJECTIVE: Enalapril has shown satisfactory potential in controlling increased and sustained blood pressure (BP). However, multiple dysregulated mechanisms that interact with each other and are involved in the pathophysiology of arterial hypertension may not be affected, contributing to the remaining cardiovascular risk. Using an exercise training protocol, we investigated whether adding both approaches to arterial hypertension management could promote higher modulation of regulatory mechanisms of BP in postmenopausal rats. METHODS: Spontaneously hypertensive rats were allocated into sedentary (S) and ovariectomized groups: sedentary (OS), sedentary treated with enalapril maleate (OSE) and trained treated with enalapril maleate (OTE). Both the pharmacological and exercise training protocols lasted for 8 weeks. The BP was directly recorded. Inflammation and oxidative stress were evaluated in the cardiac tissue. RESULTS: Although BP reduction was similar between OSE and OTE, trained group showed lower vasopressor systems outflow after sympathetic ganglion blocking by hexamethonium (mean BP) (OTE: -53.7 ±â€Š9.86 vs. OS: -75.7 ±â€Š19.2 mmHg). Bradycardic and tachycardic response were increased in OTE group (-1.4 ±â€Š0.4 and -2.6 ±â€Š0.4 vs. OS: -0.6 ±â€Š0.3 and -1.3 ±â€Š0.4 bpm/mmHg, respectively), as well as BP variability. In addition, the combination of approaches induced an increase in interleukin 10, antioxidant defense (catalase and glutathione peroxidase) and nitrite levels compared with the OS group. CONCLUSION: Despite similar BP, the inclusion of exercise training in antihypertensive drug treatment exacerbates the positive adaptations induced by enalapril alone on autonomic, inflammatory and oxidative stress profiles, probably affecting end-organ damage and remaining risk.

Renin-angiotensin-aldosterone system blockers effect in chronic kidney disease progression in hypertensive elderly patients without proteinuria: PROERCAN trial.

INTRODUCTION: Evidence about nefroprotective effect with RAAS blockers in elderly patients with chronic kidney disease (CKD) without proteinuria is lacking. The primary outcome of our study is to evaluate the impact of RAAS blockers in CKD progression in elderly patients without proteinuria. MATERIALS AND METHODS: Multicenter open-label, randomized controlled clinical trial including patients over 65 year-old with hypertension and CKD stages 3-4 without proteinuria. Patients were randomized in a 1:1 ratio to either receive RAAS blockers or other antihypertensive drugs and were followed up for three years. Primary outcome is estimated glomerular filtration rate (eGFR) decline at 3 years. Secondary outcome measures include BP control, renal and cardiovascular events and mortality. RESULTS: 88 patients were included with a mean age of 77.9±6.1 years and a follow up period of 3 years: 40 were randomized to RAAS group and 48 to standard treatment. Ethiology of CKD was: 53 vascular, 16 interstitial and 19 of unknown ethiology. In the RAAS group eGFR slope during follow up was -4.3±1.1ml/min, whereas in the standard treatment group an increase on eGFR was observed after 3 years (+4.6±0.4ml/min), p=0.024. We found no differences in blood pressure control, number of antihypertensive drugs, albuminuria, potassium serum levels, incidence of cardiovascular events nor mortality during the follow up period. CONCLUSIONS: In elderly patients without diabetes nor cardiopathy and with non proteinuric CKD the use of RAAS blockers does not show a reduction in CKD progression. The PROERCAN (PROgresión de Enfermedad Renal Crónica en ANcianos) trial (trial registration: NCT03195023).

Pharmacological inhibition of the ACE/Ang-2/AT1 axis alleviates mechanical ventilation-induced pulmonary fibrosis.

Mechanical ventilation (MV) is an essential therapy for acute respiratory distress syndrome (ARDS) and pulmonary fibrosis. However, it can also induce mechanical ventilation-induced pulmonary fibrosis (MVPF) and the underlying mechanism remains unknown. Based on a mouse model of MVPF, the present study aimed to explore the role of the angiotensin-converting enzyme/angiotensin II/angiotensin type 1 receptor (ACE/Ang-2/AT1R) axis in the process of MVPF. In addition, recombinant angiotensin-converting enzyme 2(rACE2), AT1R inhibitor valsartan, AGTR1-directed shRNA and ACE inhibitor perindopril were applied to verify the effect of inhibiting ACE/Ang-2/AT1R axis in the treatment of MVPF. Our study found MV induced an inflammatory reaction and collagen deposition in mouse lung tissue accompanied by the activation of ACE in lung tissue, increased concentration of Ang-2 in bronchoalveolar lavage fluid (BALF), and upregulation of AT1R in alveolar epithelial cells. The process of pulmonary fibrosis could be alleviated by the application of the ACE inhibitor perindopril, ATIR inhibitor valsartan and AGTR1-directed shRNA. Meanwhile, rACE2 could also alleviate MVPF through the degradation of Ang-2. Our finding indicated the ACE/Ang-2/AT1R axis played an essential role in the pathogenesis of MVPF. Pharmacological inhibition of the ACE/Ang-2/AT1R axis might be a promising strategy for the treatment of MVPF.

The fate of antibiotic resistance genes in wastewater containing microalgae treated by chlorination, ultra-violet, and Fenton reaction.

Antibiotic resistance genes (ARGs) and bacteria (ARBs) in the effluent of wastewater treatment plants (WWTPs) are of utmost importance for the dissemination of ARGs in natural aquatic environments. Therefore, there is an urgent need for effective technologies to eliminate WWTP ARGs/ARBs and mitigate the associated risks posed by the discharged ARG in aquatic environments. To test the effective technology for eliminating ARGs/ARBs, we compared the removal of ARGs and ARBs by three different tertiary treatments, namely ultra-violet (UV) disinfection, chlorination disinfection, and Fenton oxidation. Then, the treated wastewater was co-cultured with Chlorella vulgaris (representative of aquatic biota) to investigate the fate of discharged ARGs into the aquatic environment. The results demonstrated that chlorination (at a chlorine concentration of 15 mg/L) and Fenton (at pH 2.73, with 0.005 mol/L Fe2+ and 0.0025 mol/L H2O2) treatment showed higher efficacy in ARG removal (1.8 - 4.17 logs) than UV treatment (15 min) (1.29 - 3.87 logs). Moreover, chlorine at 15 mg/L and Fenton treatment effectively suppressed ARB regeneration while UV treatment for 15 min could not. Regardless of treatments tested in this study, the input of treated wastewater to the Chlorella system increased the number of ARGs and mobile genetic elements (MGEs), indicating the potential risk of ARG dissemination associated with WWTP discharge. Among the wastewater-Chlorella co-culture systems, chlorination resulted in less of an increase in the number of ARGs and MGEs compared to Fenton and UV treatment. When comparing the wastewater systems to the co-culture systems, it was observed that Chlorella vulgaris reduced the number of ARGs and MGEs in chlorination and UV-treated wastewater; however, Chlorella vulgaris promoted ARG survival in Fenton-treated water, suggesting that aquatic microalgae might act as a barrier to ARG dissemination. Overall, chlorination treatment not only effectively removes ARGs and inhibits ARB regeneration but also shows a lower risk of ARG dissemination. Therefore, chlorination is recommended for practical application in controlling the spread of discharged ARGs from WWTP effluent in natural aquatic environments.

Molecular level removal of antibiotic resistant bacteria and genes: A review of interfacial chemical in advanced oxidation processes.

As a kind of novel and persistent environmental pollutants, antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) have been frequently detected in different aquatic environment, posing potential risks to public health and ecosystems, resulting in a biosecurity issue that cannot be ignored. Therefore, in order to control the spread of antibiotic resistance in the environment, advanced oxidation technology (such as Fenton-like, photocatalysis, electrocatalysis) has become an effective weapon for inactivating and eliminating ARB and ARGs. However, in the process of advanced oxidation technology, studying and regulating catalytic active sites at the molecular level and studying the adsorption and surface oxidation reactions between catalysts and ARGs can achieve in-depth exploration of the mechanism of ARGs removal. This review systematically reveals the catalytic sites and related mechanisms of catalytic antagonistic genes in different advanced oxidation processes (AOPs) systems. We also summarize the removal mechanism of ARGs and how to reduce the spread of ARGs in the environment through combining a variety of characterization methods. Importantly, the potential of various catalysts for removing ARGs in practical applications has also been recognized, providing a promising approach for the deep purification of wastewater treatment plants.

To what extent do water reuse treatments reduce antibiotic resistance indicators? A comparison of two full-scale systems.

Water reuse is an essential strategy for reducing water demand from conventional sources, alleviating water stress, and promoting sustainability, but understanding the effectiveness of associated treatment processes as barriers to the spread of antibiotic resistance is an important consideration to protecting human health. We comprehensively evaluated the reduction of antibiotic resistance genes (ARGs) and antibiotic-resistant bacteria (ARB) in two field-operational water reuse systems with distinct treatment trains, one producing water for indirect potable reuse (ozone/biologically-active carbon/granular activated carbon) and the other for non-potable reuse (denitrification-filtration/chlorination) using metagenomic sequencing and culture. Relative abundances of total ARGs/clinically-relevant ARGs and cultured ARB were reduced by several logs during primary and secondary stages of wastewater treatment, but to a lesser extent during the tertiary water reuse treatments. In particular, ozonation tended to enrich multi-drug ARGs. The effect of chlorination was facility-dependent, increasing the relative abundance of ARGs when following biologically-active carbon filters, but generally providing a benefit in reduced bacterial numbers and ecological and human health resistome risk scores. Relative abundances of total ARGs and resistome risk scores were lowest in aquifer samples, although resistant Escherichia coli and Klebsiella pneumoniae were occasionally detected in the monitoring well 3-days downgradient from injection, but not 6-months downgradient. Resistant E. coli and Pseudomonas aeruginosa were occasionally detected in the nonpotable reuse distribution system, along with increased levels of multidrug, sulfonamide, phenicol, and aminoglycoside ARGs. This study illuminates specific vulnerabilities of water reuse systems to persistence, selection, and growth of ARGs and ARB and emphasizes the role of multiple treatment barriers, including aquifers and distribution systems.

Gamma-ray irradiation as an effective method for mitigating antibiotic resistant bacteria and antibiotic resistance genes in aquatic environments.

The prevalence of antibiotic resistance genes (ARGs) in municipal wastewater treatment plants (MWTPs) has emerged as a significant environmental concern. Despite advanced treatment processes, high levels of ARGs persist in the secondary effluent from MWTPs, posing ongoing environmental risks. This study explores the potential of gamma-ray irradiation as a novel approach for sterilizing antibiotic-resistant bacteria (ARB) and reducing ARGs in MWTP secondary effluent. Our findings reveal that gamma-ray irradiation at an absorbed dose of 1.6 kGy effectively deactivates all culturable bacteria, with no subsequent revival observed after exposure to 6.4 kGy and a 96-h incubation in darkness at room temperature. The removal efficiencies for a range of ARGs, including tetO, tetA, blaTEM-1, sulI, sulII, and tetW, were up to 90.5% with a 25.6 kGy absorbed dose. No resurgence of ARGs was detected after irradiation. Additionally, this study demonstrates a considerable reduction in the abundances of extracellular ARGs, with the transformation efficiencies of extracellular tetracycline and sulfadiazine resistance genes decreasing by 56.3-81.8% after 25.6 kGy irradiation. These results highlight the effectiveness of gamma-ray irradiation as an advanced and promising method for ARB sterilization and ARG reduction in the secondary effluent of MWTPs, offering a potential pathway to mitigate environmental risks associated with antibiotic resistance.

Kidney organoids reveal redundancy in viral entry pathways during ACE2-dependent SARS-CoV-2 infection.

With a high incidence of acute kidney injury among hospitalized COVID-19 patients, considerable attention has been focussed on whether SARS-CoV-2 specifically targets kidney cells to directly impact renal function, or whether renal damage is primarily an indirect outcome. To date, several studies have utilized kidney organoids to understand the pathogenesis of COVID-19, revealing the ability for SARS-CoV-2 to predominantly infect cells of the proximal tubule (PT), with reduced infectivity following administration of soluble ACE2. However, the immaturity of standard human kidney organoids represents a significant hurdle, leaving the preferred SARS-CoV-2 processing pathway, existence of alternate viral receptors, and the effect of common hypertensive medications on the expression of ACE2 in the context of SARS-CoV-2 exposure incompletely understood. Utilizing a novel kidney organoid model with enhanced PT maturity, genetic- and drug-mediated inhibition of viral entry and processing factors confirmed the requirement for ACE2 for SARS-CoV-2 entry but showed that the virus can utilize dual viral spike protein processing pathways downstream of ACE2 receptor binding. These include TMPRSS- and CTSL/CTSB-mediated non-endosomal and endocytic pathways, with TMPRSS10 likely playing a more significant role in the non-endosomal pathway in renal cells than TMPRSS2. Finally, treatment with the antihypertensive ACE inhibitor, lisinopril, showed negligible impact on receptor expression or susceptibility of renal cells to infection. This study represents the first in-depth characterization of viral entry in stem cell-derived human kidney organoids with enhanced PTs, providing deeper insight into the renal implications of the ongoing COVID-19 pandemic. IMPORTANCE: Utilizing a human iPSC-derived kidney organoid model with improved proximal tubule (PT) maturity, we identified the mechanism of SARS-CoV-2 entry in renal cells, confirming ACE2 as the sole receptor and revealing redundancy in downstream cell surface TMPRSS- and endocytic Cathepsin-mediated pathways. In addition, these data address the implications of SARS-CoV-2 exposure in the setting of the commonly prescribed ACE-inhibitor, lisinopril, confirming its negligible impact on infection of kidney cells. Taken together, these results provide valuable insight into the mechanism of viral infection in the human kidney.

Characterization of four new cycloartane triterpenoids from Swietenia macrophylla and their angiotensin-I-converting enzyme inhibitory activity.

Angiotensin I-converting enzyme (ACE) inhibition is currently a common method for the treatment and control of hypertension. In this study, four new (1-4) and one known (5) cycloartane triterpenoids were isolated from the leaves of Swietenia macrophylla by chromatographic techniques and identified by their spectroscopic data and a comprehensive comparison of published data. The triterpenoids were evaluated for their ACE inhibitory potential using in vitro inhibition assays and in silico methods. The inhibition assay and enzyme kinetics results showed that the most active triterpenoid, compound 4, inhibited ACE in a mixed-type manner with an IC50 value of 57.7 ± 6.07 µM. Computer simulations revealed that compound 4 reduces the catalytic efficiency of ACE by competitive insertion into the active pocket blocking the substrate, and the binding activity occurs mainly through hydrogen bonds and hydrophobic interactions. The study showed that S. macrophylla can be a source of bioactive material and the ACE inhibitory triterpenoid could be a potential antihypertensive agent.

Renin-Angiotensin System Inhibitors Suppress the Growth of Leukemia Cells.

BACKGROUND/AIM: The renin-angiotensin system (RAS) regulates blood pressure. The RAS is also related to cell growth, and its activation has been reported in various cancer cells. Therefore, we investigated the effects of RAS inhibitors on the in vitro growth of leukemia cell lines. MATERIALS AND METHODS: THP-1, MV4-11, and TMD7 cells derived from acute myeloid leukemia, K-562 cells from chronic myeloid leukemia, and Jurkat and KOPT-K1 cells from T-lymphoblastic leukemia (T-ALL) with NOTCH1 mutations were used. We used four RAS inhibitors: the renin inhibitor aliskiren, angiotensin-converting enzyme 1 inhibitor captopril, angiotensin II type 1 receptor antagonist azilsartan, and angiotensin II type 2 receptor antagonist PD123319. Cells were cultured with the inhibitors and cell growth was assessed using a colorimetric assay. The expression of signaling proteins was assessed using immunoblotting. RESULTS: Treatment with aliskiren, azilsartan, or PD123319 suppressed the growth of all cell lines. Captopril treatment suppressed the growth of K-562, KOPT-K1, and MV4-11 cells. Flow cytometric analysis revealed that the growth suppression was due to the induction of apoptosis. Their suppressive effects on normal lymphocytes were milder than those on leukemia cells. Treatment with these inhibitors decreased MYC expression, induced caspase3 and PARP cleavage, and suppressed mTOR signaling. The treatment also suppressed NOTCH1 signaling in T-ALL cells. CONCLUSION: RAS inhibitors can be repurposed as molecular-targeted drugs for leukemia. However, the concentrations of the inhibitors were much higher than those in the plasma of patients with hypertension. Therefore, further investigation is required for their clinical use.

The effects of Salvia miltiorrhiza and ligustrazine injection combined with ACEI/ARB on diabetic kidney disease: A systematic review and meta-analysis.

BACKGROUND: In China, Salvia miltiorrhiza and ligustrazine (SML) injection are widely used as adjunctive therapy for patients with diabetic kidney disease (DKD). However, different studies have reported conflicting results. Therefore, a systematic review and meta-analysis are necessary to assess the efficacy and safety of SML injection for the treatment of DKD. METHODS: We searched 6 electronic literature databases comparing randomized controlled trials (RCTs) of angiotensin-converting enzyme inhibitor (ACEI)/angiotensin receptor blocker (ARB), SML injection in combination with ACEIs/ARBs that were conducted from inception until September 5, 2023. Two reviewers extracted data and independently assessed the risk of bias. Using the Cochrane Risk of Bias Tool for Risk Assessment. Mean differences (MD) were combined with random-effects models and the corresponding 95% confidence intervals (CI) were reported. Review Manager 5.4 software was used for meta-analysis. Stata 17.0 software was used for sensitivity analysis and Egger test. RESULTS: The combined results show that the use of SML injection along with ACEI/ARB led to better outcomes than the use of controls in terms of enhancing recovery: renal function: Serum creatinine (MD = -14.69, 95% CI (-19.38, -10.00)), Blood urea nitrogen (MD = -1.23, 95% CI (-1.72, -0.74)), Urinary ß2-microglobulin (MD = -4.58, 95% CI (-7.72, -1.44)); urinary protein: Urinary albumin excretion rate (MD = -45.74, 95% CI (-58.92, -32.56)), Urine albumin-creatinine ratio (MD = -11.93, 95% CI (-13.89, -9.96)), 24-h urine proteinuria (MD = -0.59, 95% CI (-0.86, -0.32)), Urine microalbumin (MD = -13.50, 95% CI (-20.18, -6.83)). Additionally, adjuvant therapy with SML injection enhanced results in blood glucose, blood pressure, lipids, and inflammatory responses, and no significant variations in adverse events were discovered between the 2 groups. CONCLUSIONS: In patients with DKD, combining SML injection with ACEI/ARB improves renal function, renal proteinuria, hyperglycemia, blood pressure, dyslipidemia, and inflammatory response.

Arbidol attenuates liver fibrosis and activation of hepatic stellate cells by blocking TGF-ß1 signaling.

Chronic liver diseases (CLD) impact over 800 million people globally, causing about 2 million deaths annually. Arbidol (ARB), an indole-derivative used to treat influenza virus infection, was extensively used during COVID-19 pandemic in China. In recent years, studies have shown that ARB, compared to other antiviral drugs, exhibits greater liver-protective efficacy, indicating a potential hepatoprotective effect beyond its antiviral activity. However, the mechanism remains unclear. In this study, we investigated the impact of ARB on liver injury/fibrosis in bile duct ligated (BDL) mice and its effect on spontaneous and transforming growth factor ß1 (TGF-ß1)-induced activation of primary cultured hepatic stellate cells (HSCs). Oral administration of ARB significantly ameliorated BDL-induced liver injury/fibrosis as reflected by decreased serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), reduced collagen deposition, and diminished mRNA expression of fibrosis markers. ARB notably inhibited spontaneous and TGF-ß1-induced activation of primary cultured HSCs. Moreover, ARB also drastically attenuated mRNA expression levels of platelet-derived growth factor receptor (Pdgfr), transforming growth factor-beta receptor (Tgfbr) 1, Tgfbr2, matrix metalloproteinase (Mmp)-2, and Mmp-9 in activated HSCs. We further demonstrate that ARB mitigated Smad2/3 phosphorylation in both TGF-ß1 treated HSCs and BDL mice. These data together demonstrate that the therapeutic efficacy of ARB on liver fibrosis is independent of its antiviral activity and likely is achieved by blocking TGF-ß1 signaling-mediated HSC activation.