ER stress improvement by aerobic training or enalapril differently ameliorates pathological cardiac remodeling in obese mice.

Overactivation of the classic arm of the renin-angiotensin system (RAS) is one of the main mechanisms involved in obesity-related cardiac remodeling, and a possible relationship between RAS and ER stress in the cardiovascular system have been described. Thus, the aim of this study is to evaluate if activating the protective arm of the RAS by ACE inhibition or aerobic exercise training could overturn diet-induced pathological cardiac hypertrophy by attenuating ER stress. Male C57BL/6 mice were fed a control (SC) or a high-fat diet (HF) for 16 weeks. In the 8th week, HF-fed animals were randomly divided into HF, enalapril treatment (HF-En), and aerobic exercise training (HF-Ex) groups. Body mass (BM), food and energy intake, plasma analyzes, systolic blood pressure (SBP), physical conditioning, and plasma ACE and ACE2 activity were evaluated. Cardiac morphology, and protein expression of hypertrophy, cardiac metabolism, RAS, and ER stress markers were assessed. Data presented as mean ± standard deviation and analyzed by one-way ANOVA with Holm-Sidak post-hoc. HF group had increased BM and SBP, and developed pathological concentric cardiac hypertrophy, with overactivation of the classic arm of the RAS, and higher ER stress. Both interventions reverted the increase in BM, and SBP, and favored the protective arm of the RAS. Enalapril treatment improved pathological cardiac hypertrophy with partial reversal of the concentric pattern, and slightly attenuated cardiac ER stress. In contrast, aerobic exercise training induced physiological eccentric cardiac hypertrophy, and fully diminished ER stress.

Optimal folic acid dosage in lowering homocysteine: Precision Folic Acid Trial to lower homocysteine (PFAT-Hcy).

BACKGROUND: While folic acid (FA) is widely used to treat elevated total homocysteine (tHcy), promoting vascular health by reducing vascular oxidative stress and modulating endothelial nitric oxide synthase, the optimal daily dose and individual variation by MTHFR C677T genotypes have not been well studied. Therefore, this study aimed to explore the efficacy of eight different FA dosages on tHcy lowering in the overall sample and by MTHFR C677T genotypes. METHODS: This multicentered, randomized, double-blind, controlled clinical trial included 2697 eligible hypertensive adults with elevated tHcy (≥ 10 mmol/L) and without history of stroke and cardiovascular disease. Participants were randomized into eight dose groups of FA combined with 10 mg enalapril maleate, taken daily for 8 weeks of treatment. RESULTS: The intent to treat analysis included 2163 participants. In the overall sample, increasing FA dosage led to steady tHcy reduction within the FA dosing range of 0-1.2 mg. However, a plateau in tHcy lowering was observed in FA dose range of 1.2-1.6 mg, indicating a ceiling effect. In contrast, FA doses were positively and linearly associated with serum folate levels without signs of plateau. Among MTHFR genotype subgroups, participants with the TT genotype showed greater efficacy of FA in tHcy lowering. CONCLUSIONS: This randomized trial lent further support to the efficacy of FA in lowering tHcy; more importantly, it provided critically needed evidence to inform optimal FA dosage. We found that the efficacy of FA in lowering tHcy reaches a plateau if the daily dosage exceeds 1.2 mg, and only has a small gain by increasing the dosage from 0.8 to 1.2 mg. GOV IDENTIFIER: NCT03472508 (Registration Date: March 21, 2018).

A Comparative Analysis of the Clinical Efficacy of Sacubitril Valsartan Sodium and Enalapril in Patients with Non-Valvular Ejection Fraction Reduction in Heart Failure.

Objective: Heart failure is a common cardiovascular disease, and its prevalence is increasing year by year. For patients with heart failure combined with non-valvular reduced ejection fraction, drug therapy has always been a key treatment. This study aimed to explore the clinical efficacy of sacubitril valsartan sodium and enalapril in such patients. Methods: Study design: This study used a prospective observational design. From February 2020 to February 2022, we included 123 patients with non-valvular heart failure and reduced ejection fraction who were treated in Xingtai Third Hospital. Patients were divided into two groups according to the treatment plan: Group A (n=61) received enalapril, and Group B (n=62) received nifedipine. All patients received conventional treatment. We compared the efficacy of the two groups of patients 8 weeks after treatment. During the study, the laboratory indicators, echocardiographic indicators, cardiovascular markers, and possible adverse reactions of the two groups of patients before and after treatment were recorded. Results: After 8 weeks of treatment, the effective rate of group B was higher than group A (P < .05). There were no differences in the levels of total protein, total bilirubin, total cholesterol and serum creatinine between the two groups before and after treatment (P > .05). The serum creatinine level in the two groups after treatment was higher than that before treatment, and the level in group B was lower than that in group A (P < .05). There were no statistically significant differences in the levels of total protein, total bilirubin and total cholesterol between the two groups before and after treatment (P > .05), and there was no statistically significant difference in the level of serum creatinine between the two groups before treatment (P > .05), and the level of serum creatinine after treatment was higher than that before treatment, and the level of group B was lower than that of group A (P < .05). Before treatment, there was no significant difference in the levels of high-sensitive troponin T and n-terminal brain natriuretic peptide and cyclic guanosine phosphate between the two groups (P > .05). After treatment, the levels of high-sensitive troponin T and N-terminal brain natriuretic peptide in the two groups were lower than those before treatment, and those in group B were lower than those in group A. The level of cyclic guanosine phosphate in group A was lower than that before treatment, the level of cyclic guanosine phosphate in group B was higher than that before treatment, and the level of group B was higher than that of group A (P < .05). The incidence of adverse cardiovascular events in group B was lower than that in group A (P < .05).In this study, the effective rate of treatment group B was significantly higher than that of treatment group A, indicating that treatment group B had a better therapeutic effect. In addition, there were no significant differences between the two groups in a series of biochemical parameters, but it is worth noting that after treatment, the serum creatinine level of group B was significantly lower than that of group A, which may indicate that the treatment of group B is not only more effective but also Reduces the risk of certain adverse cardiovascular events. Conclusion: The main findings of the study showed that Sacubitril valsartan sodium showed better clinical efficacy than enalapril in patients with heart failure and non-valvular reduced ejection fraction. Specifically, the drug significantly improved patients' kidney function, reduced cardiovascular marker levels, and reduced the incidence of adverse cardiovascular events. These findings have important clinical implications for guiding treatment selection in patients with heart failure.

Impact of a combination of pimobendan, furosemide, and enalapril on heart rate variability in naturally occurring, symptomatic, myxomatous mitral valve degeneration dogs.

BACKGROUND: Pimobendan, diuretics, and an angiotensin-converting enzyme inhibitor (ACEi) are widely used for the management of chronic valvular heart disease in dogs; however, the effects of that combination on heart rate variability (HRV) are unknown. The purpose of this study was to assess the HRV of symptomatic myxomatous mitral valve degeneration (MMVD) dogs in response to therapy with a combination of pimobendan, diuretics, and ACEi. RESULTS: MMVD stage C (n = 17) dogs were enrolled and a 1-hour Holter recording together with echocardiography, blood pressure measurement, and blood chemistry profiles were obtained before and 1, 3, and 6 months after oral treatment with pimobendan (0.25 mg/kg), enalapril (0.5 mg/kg), and furosemide (2 mg/kg) twice daily. The results revealed that MMVD stage C dogs at the baseline had lower values of time-domain indices, low frequency (LF), high frequency (HF), and total power, as well as higher value of LF/HF. Triple therapy significantly increases these parameters in MMVD stage C dogs (P < 0.05). A positive moderate correlation was observed between time domain parameters and a left ventricular internal diastole diameter normalized to body weight (P < 0.05). CONCLUSIONS: It can be concluded that MMVD stage C dogs possess low HRV due to either the withdrawal of parasympathetic tone or enhanced sympathetic activation, and a combination therapy was shown to enhance cardiac autonomic modulation inferred from the increased heart rate variability. Therefore, a combination therapy may be useful for restoring normal autonomic nervous system activity in dogs with MMVD stage C.

Sex Differences in Glomerular Lesions, in Atherosclerosis Progression, and in the Response to Angiotensin-Converting Enzyme Inhibitors in the ApoE-/- Mice Model.

This study analyzes sex-based differences in renal structure and the response to the Angiotensin-Converting Enzyme (ACE) inhibitor enalapril in a mouse model of atherosclerosis. Eight weeks old ApoE-/- mice received enalapril (5 mg/kg/day, subcutaneous) or PBS (control) for an additional 14 weeks. Each group consisted of six males and six females. Females exhibited elevated LDL-cholesterol levels, while males presented higher creatinine levels and proteinuria. Enalapril effectively reduced blood pressure in both groups, but proteinuria decreased significantly only in females. Plaque size analysis and assessment of kidney inflammation revealed no significant sex-based differences. However, males displayed more severe glomerular injury, with increased mesangial expansion, mesangiolysis, glomerular foam cells, and activated parietal epithelial cells (PECs). Enalapril mitigated mesangial expansion, glomerular inflammation (particularly in the female group), and hypertrophy of the PECs in males. This study demonstrates sex-based differences in the response to enalapril in a mouse model of atherosclerosis. Males exhibited more severe glomerular injury, while enalapril provided renal protection, particularly in females. These findings suggest potential sex-specific considerations for ACE inhibitor therapy in chronic kidney disease and atherosclerosis cardiovascular disease. Further research is needed to elucidate the underlying mechanism behind these observations.

MANAGEMENT OF RISKS OF ADVERSE DRUG REACTIONS ACCORDING TO ADR REPORT FORM DATA FROM LVIV REGION HEALTHCARE FACILITIES IN 2022.

The study aimed to analyse the adverse drug reactions report form data received by the State Expert Center of the Ministry of Health of Ukraine from healthcare professionals in the Lviv region in 2022. Regarding specific types of medicines, the ones with proven cause-and-effect relationships that caused the highest frequency of adverse drug reactions incidents were chemotherapeutic agents (35.5%), medicines affecting the cardiovascular system (20.3%), and non-steroidal anti-inflammatory drugs (8%). Within the penicillin class, amoxicillin potentiated by clavulanate (67%) and amoxicillin (29%) were the dominant drugs showing the highest incidence rate of adverse reactions. Among cephalosporins, ceftriaxone (46%) and cefixime (15%) were found to take the lead in terms of adverse reaction frequency. The highest proportion among all adverse drug reactions caused by penicillins and cephalosporins was attributed to allergic reactions. To confirm or rule out immediate or delayed type allergies in patients, as well as in patients with a history of immediate-type allergic reactions to ß-lactams and planned administration of another ß-lactam, it is necessary to conduct skin testing (skin prick test, or, in the case of parenteral administration, intradermal test) with the planned ß-lactam antibiotic. The second highest proportion of induced adverse drug reactions was attributed to drugs affecting the cardiovascular system (20.3%). The leading medications in the angiotensin-converting enzyme inhibitors category were enalapril (47%) and the combination of lisinopril with hydrochlorothiazide (24%). In the angiotensin II receptor blockers category of medications, valsartan (30%) and telmisartan-hydrochlorothiazide combination (20%) ranked highest. In the category of CCB drugs, amlodipine (66%) and nifedipine (20%) held the leading positions. among angiotensin-converting enzyme inhibitors, enalapril caused the most prevalent and predicted adverse reaction, that of cough, affecting 10.5% of patients, whereas, with the combination therapy of lisinopril and hydrochlorothiazide, the cough was observed in only 5.2% of patients. Angiotensin II receptor blockers have a better safety profile, particularly concerning cough. Analysis of adverse drug reactions reports for angiotensin II receptor blockers showed no cases of cough with valsartan and telmisartan-hydrochlorothiazide combination. Among calcium channel blocker medications, amlodipine emerged to rank highest, causing one of the predicted adverse drug reactions, that of lower extremity oedema in 64% of patients. The second position was taken by the combination of amlodipine with valsartan, which showed a statistically significant reduction of 14.3% (p≤0.05) in the incidence of oedema. Using amlodipine at a dose of 5 mg in combination with sartan medicines as angiotensin receptor blockers is an effective therapeutic alternative not only for enhancing blood pressure control in hypertensive patients but also for improving the safety profile of amlodipine. Among all the non-steroidal anti-inflammatory drugs prescribed to patients in the Lviv region in 2022, the highest number of adverse reactions was associated with the administration of diclofenac, ibuprofen, paracetamol, and nimesulide, causing adverse drug reactions in 22%, 19%, 17%, and 10% of cases, respectively. The most common systemic manifestations of adverse reactions with these non-steroidal anti-inflammatory drugs were allergic reactions (63.4%) and gastrointestinal disorders (26.8%). From an evidence-based medicine perspective, the most justified approach for primary and secondary prevention of gastrointestinal complications is the use of proton pump inhibitors.

Efficacy of felodipine and enalapril in the treatment of essential hypertension with coronary artery disease and the effect on levels of Salusin-ß, Apelin, and PON1 gene expression in patients.

This study aimed to analyze the effect of felodipine combined with enalapril in the treatment of patients with essential hypertension and coronary artery disease. Also, the effect of these medicines was evaluated on the peripheral blood Salusin-ß, Apelin levels, and PON1 gene expression. For this purpose, 110 patients with essential hypertension combined with coronary heart disease, admitted to the hospital from January 2019 to January 2021, were selected and randomly divided into two groups. The control group was given felodipine treatment alone, and the study group was treated with combined application of felodipine and enalapril. The treatment effect, peripheral blood Salusin-ß, Apelin, PON1 gene expression, and the safety of medication were compared between the two groups. The results showed that the post-treatment systolic blood pressure in the study group was 119.77 ± 5.23 mm Hg and diastolic blood pressure was 86.84 ± 5.42 mm Hg, both of which were significantly lower than those in the control group (127.81 ± 6.92 mm Hg and 95.13 ± 6.08 mm Hg), with statistically significant differences (p<0.05). The effective rates of the study group and the control group were 92.73% and 74.54% respectively, with statistically significant differences (P<0.05). The post-treatment peripheral blood Salusin-ßlevel in the study group was 3.77±0.53mmol/L, and Apelin was 1.94±0.58µg/L, with statistically significant differences compared to the control group (P<0.05). The PON1 gene expression in the study group was higher than those in the control group after treatment (P<0.05). Also, the results showed that there was no statistical difference in adverse reactions between the two groups (P>0.05). According to these results, the combination of felodipine and enalapril in patients with essential hypertension combined with coronary artery disease can effectively lower the patients' blood pressure and improve their peripheral blood Salusin-ß, Apelin levels, and PON1 gene expression, thus enhancing the patients' therapeutic effect with few adverse effects and high safety.

Impact of Salt Intake and Renin-Angiotensin-Aldosterone System Blockade on Lung Severe Acute Respiratory Syndrome Coronavirus 2 Host Factors.

INTRODUCTION: The angiotensin-converting enzyme 2 (ACE2) as well as the transmembrane protease serine type 2 (TMPRSS2) have been found to play roles in cell entry for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus causing coronavirus disease 2019 (COVID-19). SARS-CoV-2 infection risk and severity of COVID-19 might be indicated by the expression of ACE2 and TMPRSS2 in the lung. METHODS: A high-salt diet rat model and renin-angiotensin-aldosterone system (RAAS) blockade were used to test whether these factors affect ACE2 and TMPRSS2 expression in the lung. A normal (0.3% NaCl), a medium (2% NaCl), or a high (8% NaCl) salt diet was fed to rats for 12 weeks, along with enalapril or telmisartan, before examining the lung for histopathological alteration. Using immunofluorescence and qRT-PCR, the localization as well as mRNA expression of ACE2 and TMPRSS2 were investigated. RESULTS: The findings provide evidence that both TMPRSS2 and ACE2 are highly expressed in bronchial epithelial cells as well as ACE2 was also expressed in alveolar type 2 cells. High-salt diet exposure in rats leads to elevated ACE2 expression on protein level. Treatment with RAAS blockers had no effect on lung tissue expression of ACE2 and TMPRSS2. CONCLUSIONS: These findings offer biological support regarding the safety of these drugs that are often prescribed to COVID-19 patients with cardiovascular comorbidity. High salt intake, on the other hand, might adversely affect COVID-19 outcome. Our preclinical data should stimulate clinical studies addressing this point of concern.

Enalapril increases the urinary excretion of metformin in rats by inducing multidrug and toxin excretion protein 1 in the kidney.

Two-thirds of patients with type 2 diabetes mellitus have hypertension, and thus the combination of two or more drugs to treat these diseases is common. It has been shown that the combination of metformin and enalapril has beneficial effects, but few studies have evaluated the interactions between these two drugs. This study investigated the effects of enalapril on the pharmacokinetics and urinary excretion of metformin in rats, with a focus on transporter-mediated drug interactions. Rats were dosed orally with metformin alone (100 mg/kg) or in combination with enalapril (4 mg/kg). The concentration of metformin was measured by high performance liquid chromatography and the level of organic cation transporters (rOCTs) and multidrug and toxin excretion protein 1 (rMATE1), which mediate the uptake and efflux of metformin, respectively, were evaluated by immunoblotting. After single and 7-day dosing, the plasma concentration of metformin in the co-administration group was significantly lower than that in the metformin-only group, and the CL/F and urinary excretion were increased in the co-administration group. Enalapril did not affect the Kp of metformin but reduced renal slice-uptake of metformin. The expression of rMATE1 was increased, whereas rOCT2 expression was decreased in rat kidney. Importantly, long-term co-administration of metformin and enalapril markedly decreased the level of lactic acid and uric acid in the blood. Enalapril increases the urinary excretion of metformin through the up-regulation of rMATE1. This reveals a new mechanism of drug interactions and provides a basis for drug dosage adjustment when these drugs are co-administered.

Enalapril Diminishes the Diabetes-Induced Changes in Intestinal Morphology, Intestinal RAS and Blood SCFA Concentration in Rats.

Evidence suggests that microbiota-derived metabolites, including short-chain fatty acids (SCFAs) and trimethylamine-oxide (TMAO), affect the course of diabetic multiorgan pathology. We hypothesized that diabetes activates the intestinal renin-angiotensin system (RAS), contributing to gut pathology. Twelve-week-old male rats were divided into three groups: controls, diabetic (streptozotocin-induced) and diabetic treated with enalapril. Histological examination and RT-qPCR were performed to evaluate morphology and RAS expression in the jejunum and the colon. SCFA and TMAO concentrations in stools, portal and systemic blood were evaluated. In comparison to the controls, the diabetic rats showed hyperplastic changes in jejunal and colonic mucosa, increased plasma SCFA, and slightly increased plasma TMAO. The size of the changes was smaller in enalapril-treated rats. Diabetic rats had a lower expression of Mas receptor (MasR) and angiotensinogen in the jejunum whereas, in the colon, the expression of MasR and renin was greater in diabetic rats. Enalapril-treated rats had a lower expression of MasR in the colon. The expression of AT1a, AT1b, and AT2 receptors was similar between groups. In conclusion, diabetes produces morphological changes in the intestines, increases plasma SCFA, and alters the expression of renin and MasR. These alterations were reduced in enalapril-treated rats. Future studies need to evaluate the clinical significance of intestinal pathology in diabetes.

Enalapril and treadmill running reduce adiposity, but only the latter causes adipose tissue browning in mice.

This study investigated whether regulation of the renin-angiotensin system (RAS) by enalapril and/or aerobic exercise training (AET) causes browning of the subcutaneous white adipose tissue (sWAT). C57BL/6 mice were fed either a standard chow or a high-fat (HF) diet for 16 weeks. At Week 8, HF-fed animals were divided into sedentary (HF), enalapril (HF-E), AET (HF-T), and enalapril plus AET (HF-ET) groups. Subsequently, sWAT was extracted for morphometry, determination of RAS expression, and biomarkers of WAT browning. The HF group displayed adipocyte hypertrophy and induction of the classical RAS axis. Conversely, all interventions reduced adiposity and induced the counterregulatory RAS axis. However, only AET raised plasma irisin, increased peroxisome proliferator-activated receptor-γ coactivator-1α, and uncoupling protein-1 levels, and the expression of PR-domain containing 16 in sWAT. Therefore, we concluded that AET-induced sWAT browning was independent of the counterregulatory axis shifting of RAS in HF diet-induced obesity.

Açaí Reverses Adverse Cardiovascular Remodeling in Renovascular Hypertension: A Comparative Effect With Enalapril.

ABSTRACT: This study aimed to determine if açai seed extract (ASE) could reverse pre-existing cardiovascular and renal injury in an experimental model of renovascular hypertension (2 kidney, 1 clip, 2K1C). Young male rats (Wistar) were used to obtain 2K1C and sham groups. Animals received the vehicle, ASE (200 mg/kg/d), or enalapril (30 mg/kg/d) in drinking water from the third to sixth week after surgery. We evaluated systolic blood pressure by tail plethysmography, vascular reactivity in the rat isolated mesenteric arterial bed (MAB), serum and urinary parameters, plasma inflammatory cytokines by ELISA, MAB expression of endothelial nitric oxide synthase and its active form peNOS by Western blot, plasma and MAB oxidative damage and antioxidant activity by spectrophotometry, and vascular and cardiac structural changes by histological analysis. ASE and enalapril reduced the systolic blood pressure, restored the endothelial and renal functions, and decreased the inflammatory cytokines and the oxidative stress in 2K1C rats. Furthermore, both treatments reduced vascular and cardiac remodeling. ASE substantially reduced cardiovascular remodeling and recovered endothelial dysfunction in 2K1C rats probably through its antihypertensive, antioxidant, and anti-inflammatory actions, supplying a natural resource for the treatment of renovascular hypertension.

Late intervention in the remnant kidney model attenuates proteinuria but not glomerular filtration rate decline.

AIM: The use of animal models to predict the response to new therapies in humans is a vexing issue in nephrology. Unlike patients with chronic kidney disease (CKD), few rodent models develop a progressive decline in glomerular filtration rate (GFR) so that experimental studies frequently report a reduction in proteinuria as the primary efficacy outcome. Moreover, while humans present with established kidney disease that continues to progress, many experimental studies investigate therapies in the prevention rather than in a therapeutic setting. METHODS: We used the remnant kidney (subtotal nephrectomy [SNX]) rat model that develops a decline in GFR in conjunction with heavy proteinuria and hypertension along with the histological hallmarks of CKD in humans, glomerulosclerosis and tubulointerstitial fibrosis. Using agents that had been shown to improve GFR as well as proteinuria in the prevention setting, angiotensin-converting enzyme (ACE) inhibition with enalapril and SIRT1 activation with SRT3025, treatment was initiated 6 weeks after SNX. RESULTS: While enalapril reduced blood pressure, proteinuria and histological injury, it did not improve GFR, as measured by inulin clearance. SRT3025 improved neither GFR nor structural damage despite a reduction in proteinuria. CONCLUSION: These findings demonstrate that neither a reduction in proteinuria nor a reversal of structural damage in the kidney will necessarily translate to a restoration of kidney function.

Experimental evaluation of Enalapril effect on protein oxidative modification, proteolytic processes and cerebral morphological changes in rats with type 2 diabetes mellitus.

Neurodegenerative processes with type 2 diabetes mellitus in particular aggravate the course of the disease, change the usual life rhythm, and are a considerable part of high disability and lethality rates. AIM: The aim of the study was to examine enalapril effect on protein peroxide oxidation, activity of proteolysis and fibrinolysis enzymes and morphological state of the cerebral cortex and hippocampus under conditions of neurodegeneration in case of experimental type 2 diabetes mellitus. MATERIALS AND METHODS: Changes in the content of protein peroxide oxidation products activity of proteolysis and fibrinolysis enzymes in the cerebral cortex and hippocampus are examined under enalapril effect (1 mg/kg) in nonlinear laboratory albino male rats with neurodegeneration under conditions of type 2 diabetes mellitus simulated by streptozotocin and high-fat diet. RESULTS: After introduction of enalapril during 14 days for rats with type 2 diabetes mellitus the content of proteins of a neutral and main character, activity of proteolysis and fibrinolysis enzymes in the cerebral cortex and hippocampus decreases, which is indicative of reduced protein peroxide oxidation, intensified under conditions of diabetic neurodegeneration. Morphological picture of the cerebral cortex and hippocampus is characterized by a decreased amount of cells with karyopyknosis and increased relative density of the tigroid substance staining of neurons and lack of denudation signs of the vessels, which is indicative of a positive rebuilding of the neuron structure. CONCLUSIONS: The conducted study demonstrates a protective effect of enalapril in case of central neurodegeneration caused by type 2 diabetes mellitus, one of the mechanisms of which is decrease of protein peroxide oxidation in the cerebral cortex and hippocampus inhibiting the processes of nerve cells destruction.

Praliciguat inhibits progression of diabetic nephropathy in ZSF1 rats and suppresses inflammation and apoptosis in human renal proximal tubular cells.

Praliciguat, a clinical-stage soluble guanylate cyclase (sGC) stimulator, increases cGMP via the nitric oxide-sGC pathway. Praliciguat has been shown to be renoprotective in rodent models of hypertensive nephropathy and renal fibrosis. In the present study, praliciguat alone and in combination with enalapril attenuated proteinuria in the obese ZSF1 rat model of diabetic nephropathy. Praliciguat monotherapy did not affect hemodynamics. In contrast, enalapril monotherapy lowered blood pressure but did not attenuate proteinuria. Renal expression of genes in pathways involved in inflammation, fibrosis, oxidative stress, and kidney injury was lower in praliciguat-treated obese ZSF1 rats than in obese control rats; fasting glucose and cholesterol were also lower with praliciguat treatment. To gain insight into how tubular mechanisms might contribute to its pharmacological effects on the kidneys, we studied the effects of praliciguat on pathological processes and signaling pathways in cultured human primary renal proximal tubular epithelial cells (RPTCs). Praliciguat inhibited the expression of proinflammatory cytokines and secretion of monocyte chemoattractant protein-1 in tumor necrosis factor-α-challenged RPTCs. Praliciguat treatment also attenuated transforming growth factor-ß-mediated apoptosis, changes to a mesenchyme-like cellular phenotype, and phosphorylation of SMAD3 in RPTCs. In conclusion, praliciguat improved proteinuria in the ZSF1 rat model of diabetic nephropathy, and its actions in human RPTCs suggest that tubular effects may contribute to its renal benefits, building upon strong evidence for the role of cGMP signaling in renal health.

Early antihypertensive treatment and ischemia-induced acute kidney injury.

Acute kidney injury (AKI) frequently complicates major surgery and can be associated with hypertension and progress to chronic kidney disease, but reports on blood pressure normalization in AKI are conflicting. In the present study, we investigated the effects of an angiotensin-converting enzyme inhibitor, enalapril, and a soluble epoxide hydrolase inhibitor, 1-trifluoromethoxyphenyl-3-(1-propionylpiperidin-4-yl)urea (TPPU), on renal inflammation, fibrosis, and glomerulosclerosis in a mouse model of ischemia-reperfusion injury (IRI)-induced AKI. Male CD1 mice underwent unilateral IRI for 35 min. Blood pressure was measured by tail cuff, and mesangial matrix expansion was quantified on methenamine silver-stained sections. Renal perfusion was assessed by functional MRI in vehicle- and TPPU-treated mice. Immunohistochemistry was performed to study the severity of AKI and inflammation. Leukocyte subsets were analyzed by flow cytometry, and proinflammatory cytokines were analyzed by quantitative PCR. Plasma and tissue levels of TPPU and lipid mediators were analyzed by liquid chromatography mass spectrometry. IRI resulted in a blood pressure increase of 20 mmHg in the vehicle-treated group. TPPU and enalapril normalized blood pressure and reduced mesangial matrix expansion. However, inflammation and progressive renal fibrosis were severe in all groups. TPPU further reduced renal perfusion on days 1 and 14. In conclusion, early antihypertensive treatment worsened renal outcome after AKI by further reducing renal perfusion despite reduced glomerulosclerosis.

Angiotensin-converting enzyme inhibitor treatment early after myocardial infarction attenuates acute cardiac and neuroinflammation without effect on chronic neuroinflammation.

PURPOSE: Myocardial infarction (MI) triggers a local inflammatory response which orchestrates cardiac repair and contributes to concurrent neuroinflammation. Angiotensin-converting enzyme (ACE) inhibitor therapy not only attenuates cardiac remodeling by interfering with the neurohumoral system, but also influences acute leukocyte mobilization from hematopoietic reservoirs. Here, we seek to dissect the anti-inflammatory and anti-remodeling contributions of ACE inhibitors to the benefit of heart and brain outcomes after MI. METHODS: C57BL/6 mice underwent permanent coronary artery ligation (n = 41) or sham surgery (n = 9). Subgroups received ACE inhibitor enalapril (20 mg/kg, oral) either early (anti-inflammatory strategy; 10 days treatment beginning 3 days prior to surgery; n = 9) or delayed (anti-remodeling; continuous from 7 days post-MI; n = 16), or no therapy (n = 16). Cardiac and neuroinflammation were serially investigated using whole-body macrophage- and microglia-targeted translocator protein (TSPO) PET at 3 days, 7 days, and 8 weeks. In vivo PET signal was validated by autoradiography and histopathology. RESULTS: Myocardial infarction evoked higher TSPO signal in the infarct region at 3 days and 7 days compared with sham (p < 0.001), with concurrent elevation in brain TSPO signal (+ 18%, p = 0.005). At 8 weeks after MI, remote myocardium TSPO signal was increased, consistent with mitochondrial stress, and corresponding to recurrent neuroinflammation. Early enalapril treatment lowered the acute TSPO signal in the heart and brain by 55% (p < 0.001) and 14% (p = 0.045), respectively. The acute infarct signal predicted late functional outcome (r = 0.418, p = 0.038). Delayed enalapril treatment reduced chronic myocardial TSPO signal, consistent with alleviated mitochondrial stress. Early enalapril therapy tended to lower TSPO signal in the failing myocardium at 8 weeks after MI (p = 0.090) without an effect on chronic neuroinflammation. CONCLUSIONS: Whole-body TSPO PET identifies myocardial macrophage infiltration and neuroinflammation after MI, and altered cardiomyocyte mitochondrial density in chronic heart failure. Improved chronic cardiac outcome by enalapril treatment derives partially from acute anti-inflammatory activity with complementary benefits in later stages. Whereas early ACE inhibitor therapy lowers acute neuroinflammation, chronic alleviation is not achieved by early or delayed ACE inhibitor therapy, suggesting a more complex mechanism underlying recurrent neuroinflammation in ischemic heart failure.

Angiotensin inhibition and cellular senescence in the developing rat kidney.

Cellular senescence is important for the maintenance of tissue homeostasis during normal development. In this study, we aimed to investigate the effect of renin angiotensin system (RAS) blockade on renal cell senescence in the developing rat kidney. Newborn rat pups were treated with enalapril (30 mg/kg/day) or vehicle for seven days after birth. We investigated the intrarenal expressions of cell cycle regulators p21 and p16 with immunoblots and immunohistochemistry at postnatal day 8. For the determination of renal cellular senescence, immunostaining for senescence-associated ß-galactosidase (SA-ß-gal) and telomerase reverse transcriptase (TERT) was also performed. Enalapril treatment showed significant alterations in cellular senescence in neonatal rat kidneys. In the enalapril-treated group, intrarenal p16 and p21 protein expressions decreased compared to controls. The expressions of both p21 and p16 were reduced throughout the renal cortex and medulla of enalapril-treated rats. The immunoreactivity of TERT in enalapril-treated kidneys was also weaker than that in control kidneys. Control kidneys revealed a clear positive SA-ß-gal signal in the cortical tubules; however, SA-ß-gal activity was noticeably lower in the enalapril-treated kidneys than in control kidneys. Interruption of the RAS during postnatal nephrogenesis may disrupt physiologic renal cellular senescence in the developing rat kidney.

Brain renin-angiotensin system blockade with orally active aminopeptidase A inhibitor prevents cardiac dysfunction after myocardial infarction in mice.

Brain renin-angiotensin system (RAS) hyperactivity has been implicated in sympathetic hyperactivity and progressive left ventricular (LV) dysfunction after myocardial infarction (MI). Angiotensin III, generated by aminopeptidase A (APA), is one of the main effector peptides of the brain RAS in the control of cardiac function. We hypothesized that orally administered firibastat (previously named RB150), an APA inhibitor prodrug, would attenuate heart failure (HF) development after MI in mice, by blocking brain RAS hyperactivity. Two days after MI, adult male CD1 mice were randomized to three groups, for four to eight weeks of oral treatment with vehicle (MI + vehicle), firibastat (150 mg/kg; MI + firibastat) or the angiotensin I converting enzyme inhibitor enalapril (1 mg/kg; MI + enalapril) as a positive control. From one to four weeks post-MI, brain APA hyperactivity occurred, contributing to brain RAS hyperactivity. Firibastat treatment normalized brain APA hyperactivity, with a return to the control values measured in sham group two weeks after MI. Four and six weeks after MI, MI + firibastat mice had a significant lower LV end-diastolic pressure, LV end-systolic diameter and volume, and a higher LV ejection fraction than MI + vehicle mice. Moreover, the mRNA levels of biomarkers of HF (Myh7, Bnp and Anf) were significantly lower following firibastat treatment. For a similar infarct size, the peri-infarct area of MI + firibastat mice displayed lower levels of mRNA for Ctgf and collagen types I and III (markers of fibrosis) than MI + vehicle mice. Thus, chronic oral firibastat administration after MI in mice prevents cardiac dysfunction by normalizing brain APA hyperactivity, and attenuates cardiac hypertrophy and fibrosis.

Angiotensin-converting enzyme inhibitors attenuated advanced glycation end products-induced renal tubular hypertrophy via enhancing nitric oxide signaling.

Advanced glycation end products (AGE) and angiotensin II were closely correlated with the progression of diabetic nephopathy (DN). Nitric oxide (NO) is a protective mediator of renal tubular hypertrophy in DN. Here, we examined the molecular mechanisms of angiotensin-converting enzyme inhibitor (ACEI) and NO signaling responsible for diminishing AGE-induced renal tubular hypertrophy. In human renal proximal tubular cells, AGE decreased NO production, inducible NOS activity, guanosine 3',5'-cyclic monophosphate (cGMP) synthesis, and cGMP-dependent protein kinase (PKG) activation. All theses effects of AGE were reversed by treatment with ACEIs (captopril and enalapril), the NO donor S-nitroso-N-acetylpenicillamine (SNAP), and the PKG activator 8-para-chlorophenylthio-cGMPs (8-pCPT-cGMPs). In addition, AGE-enhanced activation of extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 mitogen-activated protein kinase (MAPK) were clearly reduced by captopril, enalapril, SNAP, and 8-pCPT-cGMPs. The abilities of ACEIs and NO/PKG activation to inhibit AGE-induced hypertrophic growth were verified by the observation that captopril, enalapril, SNAP, and 8-pCPT-cGMPs decreased protein levels of fibronectin, p21 Waf1/Cip1 , and receptor for AGE. The results of the present study suggest that ACEIs significantly reduced AGE-increased ERK/JNK/p38 MAPK activation and renal tubular hypertrophy partly through enhancement of the NO/PKG pathway.