Angiotensin-converting Enzyme Inhibition Research Articles

Brief Early Life Angiotensin-Converting Enzyme Inhibition Offers Renoprotection in Sheep with a Solitary Functioning Kidney at 8 Months of Age.

Children born with a solitary functioning kidney (SFK) are predisposed to develop hypertension and kidney injury. Glomerular hyperfiltration and hypertrophy contribute to the pathophysiology of kidney injury. Angiotensin-converting enzyme inhibition (ACEi) can mitigate hyperfiltration and may be therapeutically beneficial in reducing progression of kidney injury in those with an SFK. SFK was induced in male sheep fetuses at 100 days gestation (term=150 days). Between 4 and 8 weeks of age, SFK lambs received enalapril (SFK+ACEi; 0.5mg/kg per day, once daily, orally) or vehicle (SFK). At 8 months, we examined BP, basal kidney function, renal functional reserve (RFR; GFR response to combined amino acid and dopamine infusion), GFR response to nitric oxide synthase (NOS) inhibition, and basal nitric oxide (NO) bioavailability (basal urinary total nitrate and nitrite [NOx]). SFK+ACEi prevented albuminuria and resulted in lower basal GFR (16%), higher renal blood flow (approximately 22%), and lower filtration fraction (approximately 35%), but similar BP, compared with vehicle-treated SFK sheep. Together with greater recruitment of RFR (approximately 14%) in SFK+ACEi than SFK animals, this indicates a reduction in glomerular hyperfiltration-mediated kidney dysfunction. During NOS inhibition, the decrease in GFR (approximately 14%) was greater among SFK+ACEi than among SFK animals. Increased (approximately 85%) basal urinary total NOx in SFK+ACEi compared with SFK animals indicates elevated NO bioavailability likely contributed to improvements in kidney function and prevention of albuminuria. Brief and early ACEi in SFK is associated with reduced glomerular hyperfiltration-mediated kidney disease up to 8 months of age in a sheep model.

Effect of angiotensin-converting enzyme inhibition on cardiovascular adaptation to exercise training.

Angiotensin‐converting enzyme (ACE) activity may be one determinant of adaptability to exercise training, but well‐controlled studies in humans without confounding conditions are lacking. Thus, the purpose of the present study was to investigate whether ACE inhibition affects cardiovascular adaptations to exercise training in healthy humans. Healthy participants of both genders (40 ± 7 years) completed a randomized, double‐blind, placebo‐controlled trial. Eight weeks of exercise training combined with placebo (PLA, n = 25) or ACE inhibitor (ACEi, n = 23) treatment was carried out. Before and after the intervention, cardiovascular characteristics were investigated. Mean arterial blood pressure was reduced (p < 0.001) by −5.5 [−8.4; −2.6] mmHg in ACEi, whereas the 0.7 [−2.0; 3.5] mmHg fluctuation in PLA was non‐significant. Maximal oxygen uptake increased (p < 0.001) irrespective of ACE inhibitor treatment by 13 [8; 17] % in ACEi and 13 [9; 17] % in PLA. In addition, skeletal muscle endurance increased (p < 0.001) to a similar extent in both groups, with magnitudes of 82 [55; 113] % in ACEi and 74 [48; 105] % in PLA. In contrast, left atrial volume decreased (p < 0.05) by −9 [−16; −2] % in ACEi, but increased (p < 0.01) by 14 [5; 23] % in PLA. Total hemoglobin mass was reduced (p < 0.01) by −3 [−6; −1] % in ACEi, while a non‐significant numeric increase of 2 [−0.4; 4] % existed in PLA. The lean mass remained constant in ACEi but increased (p < 0.001) by 3 [2; 4] % in PLA. In healthy middle‐aged adults, 8 weeks of high‐intensity exercise training increases maximal oxygen uptake and skeletal muscle endurance irrespective of ACE inhibitor treatment. However, ACE inhibitor treatment counteracts exercise training‐induced increases in lean mass and left atrial volume. ACE inhibitor treatment compromises total hemoglobin mass.

Antihypertensive and In Silico Docking Studies OF Phytoconstituents Isolated from Syzygium Alternifolium Bark

Aim of the Study: Pharmacological examination was done for methanolic extract Syzygium alternifolium bark (MESA) for its antihypertensive activity, Angiotensin converting enzyme (ACE) inhibition by in vitro and in vivo studies, antioxidant activity via radical scavenging activity.&#x0D; Methods: Albino Wistar rats were allowed to treat with dexamethasone (30 μg/kg/day s.c) or saline for about 14 days. Methanolic extract of Syzygium alternifolium (300 mg/kg, b.w., p.o.) is administered from day 8 to 14 day of study to the treatment group. Chronic fructose treatment in rats showed to increase blood pressure in relationship with insulin blockade. MESA (300 mg/kg b.w, p.o) was capable of preventing the origin of hypertension by diminishing the raised blood levels i.e., blood pressure.&#x0D; Results and Discussion: The decrease in the blood pressure is accredited to the restraint of ACE. The preliminary phytochemical examination suggests that the MESA has alkaloids, flavonoids, glycosides, steroids, sugars, proteins and tannins. MESA exhibited 1, 1-diphenyl-2-picrylhydrazyl interrupting radical chain reactions with IC50 value of 12.34 µg/ml just as superoxide radical scavenging ability with IC50 value of 21 µg/ml. MESA showed antihypertensive activity by limiting angiotensin converting enzyme and interrupted free radical reactions i.e., antioxidant property. These findings reveal the existence of probable active constituents of MESA. Understanding the molecular method of activity of natural product is a vital stage for creating drugs from them. The docking studies of the number of compounds were performed using mCule software. The constituents have good binding ability with ACE 1 inhibitor, Calcium channel blocker, and Renin inhibitor proteins and Ramachandran plot is analyzed.&#x0D; Conclusion: The compounds from Syzygium alternifolium bark have shown antihypertensive activity when compared with standard drug Amlodipine.

Structural characterization and angiotensin-converting enzyme (ACE) inhibitory mechanism of Stropharia rugosoannulata mushroom peptides prepared by ultrasound

To reveal the structural characteristics and angiotensin-converting enzyme (ACE) inhibition mechanism of Stropharia rugosoannulata mushroom peptides prepared by multifrequency ultrasound, the peptide distribution, amino acid sequence composition characteristics, formation pathway, and ACE inhibition mechanism of S. rugosoannulata mushroom peptides were studied. It was found that the peptides in S. rugosoannulata mushroom samples treated by multifrequency ultrasound (probe ultrasound and bath ultrasound mode) were mainly octapeptides, nonapeptides, and decapeptides. Hydrophobic amino acids were the primary amino acids in the peptides prepared by ultrasound, and the amino acid dissociation of the peptide bonds at the C-terminal under the action of ultrasound was performed mainly to produce hydrophobic amino acids. Pro and Val (PV), Arg and Pro (RP), Pro and Leu (PL), and Asp (D) combined with hydrophobic amino acids were the characteristic amino acid sequence basis of the active peptides of the S. rugosoannulata mushroom. The docking results of active peptides and ACE showed that hydrogen bond interaction remained the primary mode of interaction between ACE and peptides prepared by ultrasound. The peptides can bind to the amino acid residues in the ACE active pocket, zinc ions, or key amino acids in the domain, and this results in inhibition of ACE activity. Cation–pi interactions also played an important role in the binding of mushroom peptides to ACE. This study explains the structural characteristics and ACE inhibition mechanism used by S. rugosoannulata mushroom peptides prepared by ultrasound, and it will provide a reference for the development and application of S. rugosoannulata mushroom peptides.

Alpha amylase and angiotensin converting enzyme inhibitory potential of aqueous extract of Azanza garckeana fruit

Diabetes mellitus and hypertension are common diseases affecting a lot of people. Alpha amylase and angiotensin-converting enzyme (ACE) inhibitors are used to treat type II diabetes and hypertension respectively. This study investigated the alpha amylase and ACE inhibitory potential of Azanza garckeana fruits. Phytochemical screening, α-amylase and ACE inhibitory potential of the aqueous extract of A. garckeana fruit was determined using standard procedures. The mode of inhibition of α-amylase by A. garckeana fruit was determined from the Lineweaver-Burk plot. Alkaloids, flavonoids, anthraquinones, steroids, tannins, phenols and terpenoids were present in the aqueous extract of A. garkeana fruit. The percent inhibition of α-amylase was greater than 50%. The IC50 values were 2.6 ± 0.02 and 0.04 ± 0.09 for the extract and acarbose (standard drug) respectively. The Lineweaver-Burk plot showed that extract Vmax did not change when compared to the no inhibitor (no extract) but the km increased. The percent inhibition of ACE by A. garckeana was also greater than 50%. Its IC50 was 0.625 ± 0.03 while that of the standard drug (captopril) was 0.875 ± 0.07. Thus A. garckeana inhibited α-amylase and ACE and can be used to treat type II diabetes and hypertension. It is a competitive inhibitor of α-amylase.

A Review on Factors and Processing Methods Affecting Antihypertensive Properties of Legumes, and Antihypertensive Properties of Selected Legumes

Hypertension is one of the major risk factors which leads to cardiovascular diseases, and the typical treatment for hypertension is drug therapy. However, as there are side effects to drug therapy, there has been an increase in research on legume proteins as biopeptides have shown antihypertensive effects. Many species of legumes have been cultivated for consumption as they are a good source of protein, carbohydrates, minerals, vitamins, and dietary fiber. Bioactive compounds of legumes potentially improve factors that affect antihypertensive properties, such as angiotensin-converting enzyme (ACE) inhibition activity, renin inhibition activity, and γ-aminobutyric acid (GABA) production. The processing method of enzymatic hydrolysis can improve ACE inhibition activity, as can be seen with horse gram, pigeon pea, and lentil hydrolysates containing potent ACE inhibitory peptides of Thr-Val-Gly-Met-Thr-Ala-Lys-Phe, Val-Val-Ser-Leu-Ser-Ile-Pro-Arg, and Asn-Ser-Leu-Thr-Leu-Pro-Ile-Leu-Arg-Tyr-Leu, while pigeon pea and kidney bean hydrolysates have shown good renin inhibition activity. Fermentation can also be used to process legumes as potent ACE inhibitory peptide Val-Val-Ser-Leu-Ser-Ile-Pro-Arg was identified from fermented pigeon pea, while kidney beans and lentils demonstrated good GABA production through natural fermentation and fermentation with microbial cultures. The germination processing method could also help improve ACE inhibition activity as horse gram has shown good inhibition activity. In vivo study of pigeon pea, kidney bean, and lentils showed potential antihypertensive properties as a significant lowering of systolic blood pressure of test subject was observed. Research done on the structure and function of antihypertensive properties of legumes can help in the development of functional food products which will be beneficial to human health.

Proteins from Tenebrio molitor: An interesting functional ingredient and a source of ACE inhibitory peptides

The angiotensin-converting enzyme (ACE) inhibitory potential of the main protein fractions from Tenebrio molitor larvae (TML) was examined to evaluate their use as a novel antihypertensive functional food. Both fractions contained YAN tripeptide, previously reported as responsible for ACE inhibition. Although YAN has been synthesized and was used as a standard for LC-MS/MS quantification and IC50 against ACE was determined, low yields of YAN from TML did not explain adequately the activity of the whole protein fraction. LC-HRMS/MS investigation led to the identification of other three peptides, which were evaluated in silico, synthesized and tested against ACE. Among them, tetrapeptide NIKY showed the most promising activity (52 µM), highlighting once more the potential of TML and paving the way for exploitation in novel foods.

Changes in the metabolite composition and enzyme activity of fermented tea during processing

As the dominant microbial strain in Fuzhuan brick tea, Eurotium cristatum (E. cristatum) can biotransform the fermentation substrate during growth and reproduction, and in so doing enhance the tea’s health benefits. Green tea contains a large number of bioactive compounds with antihypertensive potential. However, as a nonfermented tea, inactivation of various enzymes (such as polyphenol oxidase) during processing results in a single secondary metabolite with limited health effects. The novel fermented tea we studied was processed by solid-state fermentation (SSF) with E. cristatum, and the substrate was a mixture of green tea and Radix Puerariae (RP). This study was aimed at evaluating the multiple effects by E. cristatum during fermentation. Compared to the unfermented control groups, the sample groups secreted enzymes (such as polyphenol oxidase and α-amylase), and the bioactive compounds content of sample groups changed, as well as significantly higher inhibition of Angiotensin-converting enzyme (ACE) in vitro (which also implies greater antihypertensive potential). These results will help further investigations of the antihypertensive bioactive compounds of green tea and the fermentation potential of E. cristatum.

Ayçiçek Küspesinden Elde Edilen Protein Hidrolizatlarının Anjiyotensin Dönüştürücü Enzim ve Dipeptidil Peptidaz–IV İnhibisyon Aktiviteleri

In this study, the potential of sunflower protein hydrolysates to inhibit angiotensin converting enzyme (ACE) and dipeptidyl peptidase-IV (DPP-IV) enzyme was determined. Sunflower protein isolate was hydrolyzed with Alcalase and Trypsin+Chymotrypsin enzymes and the obtained protein hydrolysates were fractionated by ultrafiltration (5 kDa). The degrees of hydrolysis achieved by Alcalase and Trypsin+Chymotrypsin enzymes were 27% and 13%, respectively. The most potent ACE inhibitory activity (IC50=0.06 ± 0.01 mg/mL) was observed for the fraction that has molecular weight below 5 kDa, which was hydrolyzed by Trypsin+Chymotrypsin enzyme (P

20-OR: The Renal and Vascular Effects of Combined SGLT2 and Angiotensin Converting Enzyme Inhibition

The goal of this mechanistic trial was to determine the kidney and cardiovascular effects of combined treatment with an SGLT2i (empagliflozin 25mg QD) and an ACEi (ramipril 10mg QD) for 4 weeks in patients at risk of renal hyperfiltration. In this randomized, double-blind, placebo-controlled, cross-over trial, measurements were obtained following each of the 4 treatment phases: 1) no treatment, 2) 4-week ramipril treatment alone, 3) 4-week empagliflozin-ramipril combination treatment, and 4) 4-week placebo-ramipril combination treatment. The primary endpoint was GFR after empagliflozin-ramipril treatment compared to placebo-ramipril. At the end of each study phase the following measurements were performed under clamped euglycemia (4-6 mmol/L) : inulin (GFR) and paraaminohippurate (effective renal plasma flow, ERPF) clearances, tubular sodium handling, ambulatory blood pressure, arterial stiffness, heart rate variability, non-invasive cardiac output monitoring, plasma and urine biochemistry. Empagliflozin-ramipril treatment resulted in an 8ml/min/1.73m2 lower GFR (p=0.0061) , lower absolute proximal fluid reabsorption rate (p=0.0092) , lower absolute proximal sodium reabsorption rate (p=0.0056) , and lower urinary 8-isoprostane (p=0.0084) relative to placebo-ramipril treatment. Empagliflozin-ramipril treatment resulted in additive blood pressure lowering effects (SBP p=0.0112; DBP p=0.0032) and a lower total peripheral resistance (p=0.0368) . There were no other significant changes observed with the addition of empagliflozin. SGLT2i-ACEi combination treatment resulted in an expected GFR “dip”, suppression of oxidative stress markers, and additive declines in blood pressure and total peripheral resistance in this mechanistic study. These changes are consistent with a protective physiological profile characterized by the lowering of intraglomerular pressure and related cardiorenal risk when adding an SGLT2i to conservative therapy. Disclosure Y. Lytvyn: None. K. Kimura: Employee; 3Boehringer Ingelheim Canada Ltd./Ltée. N. Peter: Employee; Boehringer Ingelheim Pharma GmbH &amp; Co.KG. V.S. Lai: Advisory Panel; Baxter. J. Tse: None. L. Cham: None. B.A. Perkins: Advisory Panel; Abbott Diabetes, Insulet Corporation, Sanofi. Board Member; Novo Nordisk. Research Support; BMO Bank of Montreal, Novo Nordisk. Other Relationship; Abbott Diabetes, Insulet Corporation, Medtronic, Novo Nordisk. N. Soleymanlou: Employee; Boehringer Ingelheim Pharmaceuticals Inc., Boehringer Ingelheim Pharmaceuticals Inc. D. Cherney: Research Support; Boehringer Ingelheim-Lilly, Merck, Janssen, Sanofi, AstraZeneca and Novo-Nordisk. Other Relationship; AbbVie Inc., AstraZeneca, Bayer AG, Boehringer Ingelheim International GmbH, Janssen Research &amp; Development, LLC, Lilly, Maze, BMS, CSL-Behring, Merck, Otsuka, Novartis and Novo-Nordisk, Mitsubishi Tanabe Pharma Corporation, Sanofi. Funding Boehringer Ingelheim and CIHR, Diabetes Canada and the Heart and Stroke Richard Lewar Centre of Excellence and the Heart and Stroke Foundation of Canada

In vitro and in silico Evaluation of ACE2 and LOX Inhibitory Activity of Eucalyptus Essential Oils, 1,8-Cineole, and Citronellal

Eucalyptus essential oils are well-known and used especially in upper respiratory tract pathologies or diseases as herbal drug preparations. In the present study, the in vitro angiotensin-converting enzyme 2 (ACE2) and lipoxygenase (LOX) enzyme inhibitory potentials of commercial Eucalyptus globulus Labill. and Eucalyptus citriodora Hook. essential oils were evaluated for their potential anti-coronavirus disease 2019 (COVID-19), and anti-inflammatory effects. In addition, the major components, 1,8-cineole and citronellal, were evaluated for their ability to bind at the active site of either human ACE2 or human 5-LOX using an in silico setting. Before activity evaluation, Eucalyptus globulus and E citriodora essential oils were analysed by GC/FID and GC/MS, where 1,8-cineole (30%), and citronellal (80%) were identified as the major components, respectively. The in vitro ACE2 inhibition was calculated as 94.9% for E globulus, and that of E citriodora essential oil as 83.4%. In vitro LOX inhibition experiments for essential oils in the same order showed inhibitions of 71.3 and 91.4%, respectively, at 20 µg/mL test concentrations in microplate-based fluorometric assays. In addition, protein–ligand docking, and interaction profiling was used to gain structural and mechanistic insights into the in silico ACE2 and LOX inhibitory potentials of the major Eucalyptus essential oil constituents, 1,8-cineole as well as citronellal. The resulting data supported the in vitro findings; however, further in vivo studies are needed to confirm the activity.

IRW (Isoleucine-Arginine-Tryptophan) Improves Glucose Tolerance in High Fat Diet Fed C57BL/6 Mice via Activation of Insulin Signaling and AMPK Pathways in Skeletal Muscle.

IRW (Isoleucine–Arginine–Tryptophan), has antihypertensive and anti-inflammatory properties in cells and animal models and prevents angiotensin-II- and tumor necrosis factor (TNF)-α-induced insulin resistance (IR) in vitro. We investigated the effects of IRW on body composition, glucose homeostasis and insulin sensitivity in a high-fat diet (HFD) induced insulin resistant (IR) model. C57BL/6 mice were fed HFD for 6 weeks, after which IRW was incorporated into the diet (45 or 15 mg/kg body weight (BW)) until week 14. IRW45 (at a dose of 45 mg/kg BW) reduced BW (p = 0.0327), fat mass gain (p = 0.0085), and preserved lean mass of HFD mice (p = 0.0065), concomitant with enhanced glucose tolerance and reduced fasting glucose (p < 0.001). In skeletal muscle, IRW45 increased insulin-stimulated protein kinase B (AKT) phosphorylation (p = 0.0132) and glucose transporter 4 (GLUT4) translocation (p < 0.001). Angiotensin 2 receptor (AT2R) (p = 0.0024), phosphorylated 5′-AMP-activated protein kinase (AMPKα) (p < 0.0124) and peroxisome proliferator-activated receptor gamma (PPARγ) (p < 0.001) were enhanced in skeletal muscle of IRW45-treated mice, as was the expression of genes involved in myogenesis. Plasma angiotensin converting enzyme-2 (ACE2) activity was increased (p = 0.0016). Uncoupling protein-1 in white adipose tissue (WAT) was partially restored after IRW supplementation. IRW improves glucose tolerance and body composition in HFD-fed mice and promotes glucose uptake in skeletal muscle via multiple signaling pathways, independent of angiotensin converting enzyme (ACE) inhibition.

Factors Associated With Serological Response to SARS-CoV-2 Vaccination in Patients With Multiple Sclerosis Treated With Rituximab

B-cell-depleting monoclonal antibodies are widely used for treatment of multiple sclerosis but are associated with an impaired response to vaccines. To identify factors associated with a favorable vaccine response to tozinameran. This prospective cohort study was conducted in a specialized multiple sclerosis clinic at a university hospital from January 21 to December 1, 2021. Of 75 patients evaluated for participation who received a diagnosis of multiple sclerosis with planned or ongoing treatment with rituximab, 69 were included in the study, and data from 67 were analyzed. Sex, age, number of previous rituximab infusions, accumulated dose of rituximab, previous COVID-19 infection, time since last rituximab treatment, CD19+ B-cell count before vaccination, CD4+ T-cell count, and CD8+ T-cell count were considered potential factors associated with the main outcome. Serological vaccine responses were measured by quantitation of anti-spike immunoglobulin G (IgG) antibodies, anti-receptor-binding domain (RBD) IgG antibodies, and their neutralizing capacities. Cellular responses to spike protein-derived SARS-CoV-2 peptide pools were assessed by counting interferon gamma spot-forming units in a FluoroSpot assay. Among 60 patients with ongoing rituximab treatment (49 women [82%]; mean (SD) age, 43 [10] years), the median (range) disease duration was 9 (1-29) years, and the median (range) dose of rituximab was 2750 (500-10 000) mg during a median (range) time of 2.8 (0.5-8.3) years. The median (range) follow-up from the first vaccination dose was 7.3 (4.3-10.0) months. Vaccine responses were determined before vaccination with tozinameran and 6 weeks after vaccination. By using established cutoff values for anti-spike IgG (264 binding antibody units/mL) and anti-RBD IgG (506 binding antibody units/mL), the proportion of patients with a positive response increased with the number of B cells, which was the only factor associated with these outcomes. A cutoff for the B-cell count of at least 40/μL was associated with an optimal serological response. At this cutoff, 26 of 29 patients (90%) had positive test results for anti-spike IgG and 21 of 29 patients (72%) for anti-RBD IgG, and 27 of 29 patients (93%) developed antibodies with greater than 90% inhibition of angiotensin-converting enzyme 2. No factor associated with the cellular response was identified. Depending on the peptide pool, 21 of 25 patients (84%) to 22 of 25 patients (88%) developed a T-cell response with interferon gamma production at the B-cell count cutoff of at least 40/μL. This cohort study found that for an optimal vaccine response from tozinameran, rituximab-treated patients with multiple sclerosis may be vaccinated as soon as possible, with rituximab treatment delayed until B-cell counts have reached at least 40/μL. An additional vaccination with tozinameran should be considered at that point.

Isolation and characterization of flavonoids from roots of Rauvolfia serpentina and evaluation of their hypotensive potential through angiotensin-converting enzyme (ACE) inhibition mode of action

Isolation and characterization of flavonoids from roots of Rauvolfia serpentina and evaluation of their hypotensive potential through angiotensin-converting enzyme (ACE) inhibition mode of action

Effect of ripening and in vitro digestion on free amino acids and Angiotensin I converting enzyme inhibitory (ACE-I) potential of cow and Buffalo milk cheddar cheeses

ABSTRACT Cheddar cheese is a source of a variety of biologically active peptides and free amino acids (FAAs), which contribute to the cheese aroma, flavors, and textures. The FAA liberation and angiotensin-converting enzyme inhibition potential of cheddar cheese made from cow and buffalo milk before and after in vitro digestion by gastric and duodenal enzymes with ripening were investigated. The cheese samples were stored under refrigeration condition (4°C) for ripening for 3, 6, and 9 months. The possible differences existing in the level of FAAs were explored before and after in vitro digestion of ripened cheddar cheese made from cow and buffalo milk. The lower level of angiotensin-converting enzyme inhibition value 62.4 ± 1.04% was observed in gastric digested cheese samples after 9 months of ripening, while the highest angiotensin-converting enzyme inhibition value 93.1 ± 1.29% was observed in duodenal digested cheese samples after 6 months of ripening. This study showed that before and after in vitro digestion, highest angiotensin-converting enzyme inhibitory potential of cheddar cheese was observed between 6 and 9 months of ripening. In 9-month ripened cheese, a significant increase in the contents of glutamic, glutamine, valine, leucine, and lysine was observed after duodenal digestion in case of both cow and buffalo milk Cheddar cheeses. The contents of valine, ornithine, and tryptophan were negligible before digestion and significantly increased afterward.

MO069: Therapeutic Effects of Semaglutide as Mono and Combination Treatment with Lisinopril in a Mouse Model of Hypertension-Accelerated Diabetic Kidney Disease

Abstract BACKGROUND AND AIMS Obesity, hyperglycemia and hypertension are critical risk factors for the onset and progression of diabetic kidney disease (DKD). Emerging evidence suggests that sodium-glucose cotransporter-2 (SGLT2) inhibitors and glucagon-like peptide-1 receptor (GLP-1R) agonists improve cardiovascular and renal outcomes in type 2 diabetes patients. We have recently profiled the effects of SGLT2 and angiotensin-converting enzyme (ACE) inhibition in a model of advanced DKD facilitated by adeno-associated virus (AAV)-mediated renin overexpression in uninephrectomized (UNx) diabetic db/db mice (Østergaard et al., AJP Renal Physiol 321: F149–F161, 2021). In the present study, we evaluated the nephroprotective effects of the long-acting GLP1R agonist semaglutide, a long-acting GLP1R agonist currently approved for diabetes and obesity treatment and in clinical development for DKD. Semaglutide was profiled with and without combination treatment with lisinopril, a standard ACE inhibitor, in the db/db UNx-ReninAAV mouse model of DKD. METHOD Female db/db mice received a single intravenous injection of reninAAV 1 week prior to UNx. Six weeks post-nephrectomy, mice were randomized into treatment groups based on body weight and blood glucose in the fed state, and received vehicle (SC, QD), semaglutide 30 nmol/kg or semaglutide 30 nmol/kg (SC, QD) in combination with lisinopril 30 mg/kg (PO, QD) for 11 weeks. Treatment endpoints included blood pressure, plasma/urine biochemistry and histomorphometric markers of kidney injury. RESULTS Vehicle-dosed db/db UNx-ReninAAV mice developed hallmarks of hypertensive DKD characterized by severe albuminuria and advanced glomerulosclerosis. Compared with vehicle, semaglutide significantly reduced fed blood glucose and hemoglobin A1C levels, whereas no significant effect on plasma insulin was observed. Semaglutide significantly reduced both diastolic and systolic blood pressure as well as albuminuria and urine kidney injury molecule-1 (KIM-1) levels. Semaglutide improved kidney histopathology with notable reductions in glomerulosclerosis severity and percent area of KIM-1 staining. Combined lisinopril treatment led to further improvements in blood pressure, albuminuria and glomerulosclerosis. Semaglutide with and without lisinopril coadministration did not influence plasma urea, cystatin C and kidney CD11 expression. CONCLUSION Semaglutide improved disease hallmarks in the db/db UNx-ReninAAV mouse model of advanced DKD. Further benefits on renal functional and histological markers were obtained by combination with antihypertensive standard-of-care treatment.

Sex‐Selective Effects of Transient ACE Inhibition on Angiotensin II‐Stimulated Fibrogenic Responses

Hypertensive heart disease is characterized by cardiac fibrosis in the left ventricle (LV). Angiotensin II (Ang II) promotes cardiac fibrosis through direct actions on cardiac fibroblasts. Inhibition of endogenous Ang II production with angiotensin converting enzyme (ACE) inhibitors has been shown to reduce interstitial collagen deposition in the LV. We have previously shown that transient treatment of male spontaneously hypertensive rats (SHRs) with an ACE inhibitor suppresses the fibrogenic capacity of cardiac fibroblasts and this persists even after stopping treatment. In this study, the goal was to investigate the impact of transient ACE inhibition on subsequent Ang II‐stimulated fibrogenic responses in the LV of male and female SHR. Male and female SHR (11‐week‐old) were treated with an ACE inhibitor (enalapril, 30mg/kg/day) or vehicle for 2 weeks followed by a 2‐week washout period. At the end of the washout, rats were given Ang II (400ng/kg/min, s.c.) or vehicle (saline) for 2 weeks (n=8‐11 per group per sex). Collagen I, III, and IV gene expression was assessed via RT‐qPCR, total collagen was quantified using a hydroxyproline assay, and immunoblotting for lysyl oxidase (LOX) and periostin (Postn) was performed. In males, the Ang II‐stimulated increase in collagen gene expression (i.e. Col1a1, Col3a1, and Col4a1) was significantly attenuated in SHR previously treated with enalapril. In female rats, Ang II significantly increased the expression of Col1a1 and Col3a1 similarly, regardless of prior enalapril treatment. We found a positive correlation between the degree of increase in Col1a1 and Col3a1 as well as with Col1a1 and Col4a1 in male controls with Ang II stimulation. However, in Ang II‐stimulated male rats transiently treated with enalapril, there was a negative correlation between Col1a1 and Col3a1 and no correlation between changes in Col1a1 and Col4a1. In female rats, there were significant positive correlations in all cases regardless of prior transient ACE inhibition. Total collagen content in both male and female rats was significantly increased by Ang II in control animals, but not in those previously treated with enalapril. Additionally, in both male and female rats stimulated with Ang II, cross‐linking proteins Postn and LOX showed lower expression in SHR that were transiently treated with enalapril. These data reveal that even after stopping treatment, ACE inhibition produces persistent changes in the myocardium that render it resistant to the effects of Ang II. The effects seen in females suggests a possible dysregulation between collagen production and extracellular matrix cross‐linking events following transient ACE inhibition. Future studies will elucidate the mechanisms underlying the sex‐specific response to ACE inhibition and the long‐term protective effect in male LV, with a goal of identifying novel therapeutic targets.

Naringenin antihypertensive power is mediated via abrogation of mineralocorticoid receptor (MCR)/ angiotensin converting enzyme (ACE)/ kidney injury molecule (Kim‐1) signaling pathway

Hypertension is a condition with chronic elevation of blood pressure and a common preventable risk factor for cardiovascular disease with attendant global morbidity and mortality. The present study investigated the novel antihypertensive action of Naringenin on NƱ‐Nitro‐L‐arginine Methyl Ester (L‐NAME)‐induced hypertension together with possible molecular mechanism of action. Rats were divided into four groups. Rats in Group A were normotensive. The hypertensive group (Group B) received 40 mg/kg) of L‐NAME alone while Groups C and D were concurrently administered Naringenin (50 mg/kg) or Lisinopril (10 mg/Kg) together with L‐NAME orally for 3 weeks. Blood pressure parameters, markers of oxidative stress and renal damage were measured. The immunohistochemistry of kidney injury molecule 1, mineralocorticoid receptor and angiotensin converting enzyme were also determined. Results indicated significant increase in oxidative stress markers and decrease in serum nitric oxide bioavailability in hypertensive rats. Furthermore, there were significant increases in serum myeloperoxidase activity, urinary creatinine, albumin, and blood urea nitrogen levels in hypertensive rats in comparison to hypertensive rats treated with Naringenin. Immunohistochemistry revealed higher expression of kidney injury molecule 1, mineralocorticoid receptor and angiotensin converting enzyme in hypertensive rats. However, co‐treatment with Naringenin mitigated renal oxidative stress, normalized blood pressure and lowered the expression of kidney injury molecule 1, mineralocorticoid receptor, and angiotensin converting enzyme. Combining all, Naringenin offered a novel antihypertensive action through the down regulation of kidney injury molecule 1, deactivation of mineralocorticoid receptor and inhibition of angiotensin converting enzyme.

Screening and Structure-Activity Relationship of Potential Compounds against Proposed Targets of COVID-19 Infection

Background: With reference to COVID-19 pandemic prevailing across the globe, chloroquine and hydroxychloroquine were reported as effective against the disease to some extent. This effectiveness can be attributed to the glycosylation interruption of the Angiotensin-converting enzyme 2 (ACE2) receptor, which is a known target for SARS-CoV-2 entery. On the other hand, studies suggest that the inhibition of ACE2 can be lethal in certain cases, thereby causing cardiovascular disorders, especially in patients already suffering from heart-related diseases. Methods: In this study, the most probable targets (other than ACE2) have been proposed for the treatment of COVID-19 infection by taking chloroquine and hydroxychloroquine as reference drugs. SwissTargetPrediction and PASSonline tools were used in order to achieve this objective. Known drugs against each target possessing close relation to either viral infections or lung disorders were assessed from the DrugBank database, and simultaneous efficacy of these drugs towards other proposed targets has been analyzed. By taking the most effective drugs as a reference, similar compounds were screened from the ChEMBL library by using the SwissSimilarity tool. Finally, molecular docking studies were performed through MOE software by using screened compounds against proposed targets. Results: Four most probable targets have been proposed, which include chemokine receptors (CCRs), dipeptidyl peptidase 4 (DPP4), muscarinic acetylcholine receptors (CHRMs), and histamine Nmethyltransferase (HNMT). Furthermore, it has been evaluated that quinacrine and vildagliptin are effective against most of the proposed targets. By taking vildagliptin as well as quinacrine as reference drugs, further eight compounds with similar effectiveness against these targets have been screened from the ChEMBL library. Molecular docking studies with CCR5, DPP4, and CHRM5 suggest that the quinacrine and its analogue (ChEMBL1782742) as well as vildagliptin and its analogue (ChEMBL511785) are the most suitable compounds as HITs for these targets. Conclusions: It has been established that the quinacrine, ChEMBL1782742, vildagliptin, ChEMBL511785, mavorixafor, atropine, and N-(2-aminoethyl)-1-aziridineethanamine in descending order can be considered as effective drugs for the treatment of COVID-19 infection.

Prior Angiotensin Converting Enzyme Inhibition Differentially Alters Angiotensin II‐Induced Oxidative Stress in Male and Female Hypertensive Rats

Hypertension promotes fibrotic cardiac remodeling that involves oxidative stress and inflammation that contribute to heart failure. Transient angiotensin converting enzyme inhibitor (ACEi) treatment in male hypertensive rats (SHR) produces persistent changes in the left ventricle (LV) that render it resistant to future fibrosis and inflammation. Oxidative stress produced by NADPH oxidase (NOX) enzymes is linked to angiotensin II (Ang II)‐mediated fibrotic signaling. Ang II also promotes secretion of macrophage‐recruiting cytokines including monocyte chemoattractant protein 1 (MCP1) which can perpetuate oxidative stress. Thus the present study investigated the impact of transient ACEi‐induced cardio‐protection on subsequent Ang II‐induced inflammatory and oxidative stress responses. After a 2‐week ACEi treatment (enalapril, 30mg/kg/day) followed by a 2‐week washout period male and female SHRs (11 wk old) were infused with Ang II (400ng/kg/min, s.c.) or vehicle (saline, n=5‐11/group/sex) for 2 weeks. At time of euthanasia, a mid‐myocardial section was fixed and paraffin embedded and remaining LV tissue was collected for protein, RNA and DNA extraction. LV macrophage infiltration was determined histologically by staining for ED‐1. MCP1 gene expression was evaluated by RTqPCR, and pro‐oxidants (NOX2 and NOX4) and antioxidants (catalase and superoxide dismutase 2; SOD2) were measured by immunoblotting. Oxidative DNA damage was quantified using an 8‐hydroxy‐2’‐deoxyguanosine (8‐OHdG) ELISA. Cardiac MCP1 gene expression was increased by Ang II in both sexes with no impact of transient ACEi. However, Ang II induced LV macrophage infiltration (ED‐1) in males only which was attenuated by prior transient ACEi. LV NOX2 was increased by Ang II and attenuated by prior transient ACEi in both sexes. NOX4 was reduced in females previously treated with an ACEi, but not males. The antioxidant, catalase, was increased by Ang II in both sexes, but attenuated by transient ACEi in females only. Further, both catalase and SOD2 were positively correlated to NOX2 in females, but not males. This suggests that Ang II‐induced pro‐oxidant responses may be more tightly coupled with antioxidant responses in females. DNA damage as measured by 8‐OHdG was not significantly impacted by Ang II in males or females. However 8‐OHdG was reduced in males previously treated with an ACEi suggesting that an alternative antioxidant mechanism may be active in males previously treated with an ACEi. At this dose and duration of Ang II there is not significant oxidative DNA damage, but MCP1 and pro‐oxidants are increased in both sexes. Males exhibit greater macrophage infiltration, while females exhibit greater antioxidant responses; both of which are prevented by prior transient ACEi. In conclusion, there are sex‐specific inflammatory and oxidative stress responses to Ang II and transient ACEi that may impact future cardiac remodeling. Current and future studies will aim to identify mechanisms involved in transient ACEi‐mediated cardio‐protection and how these effects differ between males and females.