Converting Enzyme Inhibitor Enalapril Research Articles

Impact of Renin Angiotensin System Inhibition on Renal Function in Fructose-induced Salt Sensitive Blood Pressure

Combined dietary intake of fructose with high salt at levels comparable to that in the upper quintile of western population increases blood pressure, decreases glomerular filtration rate, and results in albuminuria and insulin resistance. We tested the hypothesis that chronic treatment with either an angiotensin converting enzyme inhibitor (enalapril) or angiotensin receptor blocker (losartan) will preserve glomerular filtration rate (GFR) and reduce albuminuria. Sprague Dawley rats of both sexes were instrumented with telemetry. After a baseline period on glucose+0.4% NaCl, rats were assigned to the following groups: 20% glucose+0.4%NaCl treated with vehicle (GNS+V) or 20% fructose+4% NaCl and treated with either vehicle (FHS+V), losartan 0.42 mg/kg/hr by osmotic minipump (FHS+L) or enalapril 0.21 mg/kg/hr (FHS+E). The doses of losartan and enalapril were chosen to achieve MAP similar to the control GNS+V group. Body weights did not differ among the groups upon entry into the protocol and increased similarly among the groups. Non-fasting blood glucose was elevated in all groups in both male and female rats. Mean arterial pressure (MAP) was 108±2 mmHg in GNS+V but was elevated in the FHS+V male rats, 118±2 mmHg ( P<0.01). FHS+L and FHS+E displayed MAP similar GNS+V rats: 104±2 and 106±2 mmHg, respectively. GFR assessed by transdermal FITC-sinistrin elimination was similar across all groups: 0.85±0.04 (GNS+V), 0.86±0.08 (FHS+V), 0.94±0.10 (FHS+L), 1.13±0.12 ml/min/100 g bw (FHS+E). Female rats did not display elevated MAP: 108±1 mmHg (FHS+V) vs 105±2 mmHg (GNS+V). Losartan and enalapril did not change MAP, but GFR was higher in female FHS+L rats, 1.14± 0.05, vs GNS+V 0.75±0.06 ( P < 0.05). Thus, male but not female fructose-fed rats on high salt diet display significantly higher blood pressure. Short-term fructose high salt feeding did not change GFR in either male or female rats. RAS inhibition did not impact GFR in male rats, but losartan increased GFR in female rats on high fructose plus high salt diet compared with glucose-fed female rats on normal salt diet. R01 HL163844. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

A rare case of complex ventricular arrhythmia and heart failure in a 15.5-year-old athlete

A 15.5-year-old boy, an athlete, reported to his general practitioner due to episodes of chest pain during exercise, weakness and a feeling of irregular heartbeat that had been occurring for a month. He reported episodes of fainting in the past. Physical examination revealed arrhythmia and the patient was referred for a cardiological consultation, and then admitted to a reference cardiology department for extended cardiac diagnosis. Approximately 66,000/day (49.8%) of premature ventricular beats were recorded in 24-hour Holter electrocardiogram, including episodes of non-sustained ventricular tachycardia. Echocardiography revealed left ventricular systolic dysfunction with a decrease in its ejection fraction to 51.5%. Magnetic resonance imaging of the heart was performed, which showed foci of late post-contrast enhancement, located subepicardialy in the side wall of the left ventricle, corresponding to post-inflammatory changes in the myocardium. Left and right ventricular ejection fraction on magnetic resonance imaging were 48% and 46%, respectively. Pharmacological treatment included a beta-blocker (metoprolol), propafenone and an angiotensin converting enzyme inhibitor (enalapril). During the treatment, ventricular arrhythmia subsided almost completely, a gradual improvement in left ventricular systolic function was observed, and the patient was relieved of pain. The boy was discharged home with a recommendation to continue pharmacological treatment, lead a sparing lifestyle, and postpone practicing sports. At present, the boy’s general condition is good, he does not report any complaints, takes medications regularly, and does sports only for recreation. A follow-up Holter showed only single premature ventricular beats, while echocardiography showed an improved left ventricular systolic function (ejection fraction 63%), which is a good prognostic indicator.

Promoting Mitochondrial Biogenesis Protects against Doxorubicin‐Induced Cardiomyocyte Injury

Although anthracyclines such as doxorubicin (DOX) are highly effective chemotherapeutic agents and widely used for various malignancies, they are known to cause dose‐related and life‐threatening cardiotoxicity. This well‐recognized and unpredictable complication of anthracycline therapy may be either permanent and/or reversible, leading to heart failure in many patients while severely impacting quality of life. The pathophysiology has not been fully elucidated but DOX’s activation of cell death pathways and inhibition of mitochondrial biogenesis have been implicated in disease pathogenesis. In recent clinical trials, the β‐blocker carvedilol and the angiotensin converting enzyme inhibitor (ACEi) enalapril have been shown to modestly mitigate cardiovascular events, but the mechanisms remain poorly understood. While prior studies have shown either carvedilol or enalapril might promote mitochondrial biogenesis, we reasoned whether such roles might prevent anthracycline‐induced mitochondrial dysfunction. To test this hypothesis, we investigated rat myoblastic cells (H9c2 cells) and human induced pluripotent stem cell‐derived cardiomyocytes (iPSC‐CMs), which were treated either with DOX or pretreated with carvedilol or enalapril followed by DOX. Mitochondrial respiration was examined using Seahorse assay to evaluate mitochondrial function whereas mitochondrial content was determined via qPCR and flow cytometry. Western blotting and qPCR were also performed to evaluate expression of targets involved in mitochondrial dynamics (fission/fusion) and biogenesis. DOX treatment alone resulted in decreased oxygen consumption rates (OCR) when compared with control. In contrast, carvedilol pretreatment prevented DOX‐induced suppression of mitochondrial function for both H9c2 cells and human iPSC‐CMs. One‐way ANOVA analysis indicated a significant improvement in maximal OCR with carvedilol pretreatment compared with DOX‐treatment in human iPSC‐CMs. We found that DOX treatment expectedly reduced percentage of live cells overall and one‐way ANOVA analysis indicated significant increase in mitochondrial densities. The apparent increased mitochondrial densities in the DOX‐treated group may have resulted from increased fission as opposed to biogenesis. To evaluate this possible association with mitochondrial biogenesis, western blotting and qPCR were also performed to assess for expression of targets involved in mitochondrial dynamics (fission/fusion). Our ongoing studies are evaluating alternative methods to manipulate mitochondrial content as a therapeutic maneuver. Ongoing studies are seeking to refine the combinatorial roles for regulating mitochondrial dynamics as a major contributor for cardioprotection against anthracycline‐induced cardiotoxicity.

Experimental model of congestive heart failure induced by transverse aortic constriction in BALB/c mice

IntroductionMurine transverse aortic constriction (TAC) is a frequently used model of pressure overload-induced left ventricular (LV) remodeling. However, there is considerable variability in disease progression to overt heart failure (HF) development in the most commonly used strain of mice (i.e., C57BL/6J). Studies have shown that C57BL/6J mice are more resistant than BALB/c mice to congestive HF development following myocardial infarction or angiotensin II-induced hypertension. Therefore, we tested the hypothesis that BALB/c mice may be a better research model to study TAC-induced progressive HF. MethodsFollowing sham or TAC surgery in both C57BL/6J (n = 29) and BALB/c (n = 32) mice, we evaluated cardiac dimensions and function by echocardiography at 2, 4, 8, and 12 weeks and monitored survival throughout the study. In a separate cohort of BALB/c mice, we repeated the study in the presence of the angiotensin converting enzyme inhibitor enalapril or a vehicle initiated 2 weeks post-TAC and administered for 6 weeks. At the end of the studies, we assessed the heart weight, lung weight, and plasma brain natriuretic peptide (BNP) concentration. ResultsFollowing comparable TAC, both C57BL/6J and BALB/c mice showed significant LV remodeling compared with the sham control mice. BALB/c mice progressively developed systolic dysfunction, LV dilation, lung congestion, and significant mortality, whereas C57BL/6J mice did not. In the separate cohort of BALB/c TAC mice, enalapril significantly reduced the heart weight, lung weight, and plasma BNP concentration and improved survival compared with the vehicle control. DiscussionBALB/c mice uniformly developed congestive HF post-TAC. Enalapril was effective in improving survival and reducing lung congestion in this model. The data suggest that BALB/c mice may be a better research tool than C57BL/6J mice to study TAC-induced disease progression to HF and to evaluate novel therapies for the treatment of chronic HF with reduced ejection fraction.

Measurement of Bradykinin Formation and Degradation in Blood Plasma: Relevance for Acquired Angioedema Associated With Angiotensin Converting Enzyme Inhibition and for Hereditary Angioedema Due to Factor XII or Plasminogen Gene Variants.

Bradykinin (BK)-mediated angioedema (AE) states are rare acquired or hereditary conditions involving localized edema of the subcutaneous and submucosal tissues. Citrated plasma from healthy volunteers or patients with hereditary angioedema (HAE) with normal level of C1-inhibitor (C1-INH) was used to investigate pathways of BK formation and breakdown relevant to AE physiopathology. The half-life of BK (100 nM) added to normal plasma was 34 s, a value that was increased ~12-fold when the angiotensin converting enzyme (ACE) inhibitor enalaprilat (130 nM) was added (enzyme immunoassay measurements). The BK half-life was similarly increased ~5-fold following 2 daily oral doses of enalapril maleate in healthy volunteers, finding of possible relevance for the most common form of drug-associated AE. We also addressed the kinetics of immunoreactive BK (iBK) formation and decline, spontaneous or under three standardized stimuli: tissue kallikrein (KLK-1), the particulate material Kontact-APTT™ and tissue plasminogen activator (tPA). Relative to controls, iBK production was rapid (10–20 min) and very intense in response to tPA in plasma of female heterozygotes for variants in gene F12 coding for factor XII (FXII) (p.Thr328Lys, 9 patients; p.Thr328Arg, one). An increased response to Kontact-APTT™ and an early tPA-induced cleavage of anomalous FXII (immunoblots) were also observed. Biotechnological inhibitors showed that the early response to tPA was dependent on plasmin, FXIIa and plasma kallikrein. Results from post-menopausal and pre-menopausal women with HAE-FXII were indistinguishable. The iBK production profiles in seven patients with the plasminogen p.Lys330Glu variant (HAE-PLG) did not significantly differ from those of controls, except for an unexpected, rapid and lanadelumab-resistant potentiation of KLK-1 effect. This enzyme did not cleave plasminogen or factor XII, suggesting a possible idiosyncratic interaction of the plasminogen pathogenic variant with KLK-1 activity. KLK-1 abounds in salivary glands and human saliva, hypothetically correlating with the clinical presentation of HAE-PLG that includes the swelling of the tongue, lips and contiguous throat tissues. Samples from HAE patients with normal C1-INH levels and F12 gene did not produce excessive iBK in response to stimuli. The ex vivo approach provides physiopathological insight into AE states and supports the heterogeneous physiopathology of HAE with normal C1-INH.

Salt sensitive genotype is required for high fat diet associated hypertension and renal inflammation/injury in male Dahl rats

Elevated salt sensitivity and sympathetic activity are reported to contribute to obesity/high fat diet (HFD) associated hypertension and renal injury. We have reported that feeding male Dahl salt‐sensitive (SS) rats a HFD (with normal salt) robustly increases blood pressure and sympathetic support of blood pressure, and also causes severe renal inflammation/injury, when compared to male Dahl SS rats fed a standard rat diet (10% kcal from fat). However, it is hard to distinguish the effects of HFD per se on blood pressure and renal inflammation/injury in that setting, since Dahl SS rats fed a standard diet also develop moderate hypertension and mild renal inflammation/injury. To more clearly examine the effect of the SS genotype itself, in the current study we compared the impact of HFD on blood pressure and renal inflammation/injury in male SS (SS/JrHsd) and salt‐resistant (SR/JrHsd) rats (genetic control of SS rats) (Envigo). After 24 weeks on HFD diet feeding, starting at weaning (60% kcal from fat, 0.3% NaCl), SS rats developed severe hypertension (MAP 162±5mmHg, n=6) and renal inflammation/injury as expected. But SR rats on HFD had normal blood pressure (104±8mmHg, n=8) and renal histology. Compared with SS rats, SR rats showed much smaller mean arterial pressure (MAP) responses to acute ganglion blockade (hexamethonium, 30mg/kg, ip) (−14±5mmHg vs −37±5mmHg, P<0.05) and to chronic treatment with the angiotensin converting enzyme inhibitor enalapril (250mg/kg, 7 days in drinking water) (−21±7 mmHg vs −57±8 mmHg, P<0.05). SR rats showed less HFD associated metabolic disorders as they had lower body weight and plasma levels of cholesterol and triglycerides. SR rats also had much smaller spleen weights than SS rats. Immune cell analysis by flow‐cytometry showed that the splenic CD8+ population in SR rats was higher than that found in SS rats (16.4±0.7% vs 10.3±0.4%, P<0.05), whereas the CD4+ cell population was lower than that found in SS rats (18.3±0.6% vs 21.3±0.8%, P<0.05). The ratio of splenic CD4+/CD8+ was also significantly higher in SS rats than SR rats (2.10±0.08 vs 1.13±0.05, P<0.05). There were no strain differences in NK cells and B cells. Our study indicates that in male Dahl rats on HFD, the associated hypertension, metabolic disorders and renal inflammation/injury all require a salt sensitive genotype. Our study also confirms that the mechanisms responsible for HFD induced hypertension in male Dahl SS rats include increased neurogenic support of blood pressure and increased activity of the renin‐angiotensin system. Our study further suggests that a salt sensitive genotype impacts immune system responses to HFD. The mechanisms responsible for diet associated differences in immune cell regulation in the salt sensitive genetic background remain unknown.Support or Funding InformationNHLBI 2P01HL070687 for G.D.F, J.J.G. and H.X

P4473Brain renin-angiotensin system blockade with firibastat, an orally active, central acting aminopeptidase A inhibitor prodrug prevents cardiac dysfunction after myocardial infarction in mice

Abstract Introduction Brain renin-angiotensin system (RAS) hyperactivity has been implicated in sympathetic hyperactivity and progressive left ventricular (LV) dysfunction after myocardial infarction (MI). Brain angiotensin III, generated by aminopeptidase A (APA), is one of the main effector peptides of the brain RAS in the control of cardiac function. Purpose We hypothesized that orally administered firibastat (previously named RB150), an orally central acting APA inhibitor prodrug, would attenuate heart failure (HF) development after MI in mice, by blocking brain RAS hyperactivity. Methods Two days after MI induced by the left anterior descending artery ligation, 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. Results From one to four weeks post-MI, brain APA hyperactivity occurred, contributing to brain RAS hyperactivity. Firibastat treatment during four weeks after MI normalized brain APA hyperactivity, with a return to the control values measured in the sham group. 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 markers of fibrosis such Ctgf and collagen types I and III than MI+vehicle mice. Conclusions Chronic oral firibastat administration after MI in mice normalizes brain APA hyperactivity, thereby normalizing brain RAS hyperactivity, whilst preventing cardiac dysfunction and attenuating cardiac hypertrophy and fibrosis. Acknowledgement/Funding INSERM, College de France, ANR LabCom, and Quantum Genomics

A comparison of propofol and alfaxalone in a continuous rate infusion in dogs with mitral valve insufficiency

The aim of this study was to compare alfaxalone and propofol in balanced anaesthesia using midazolam 0.5 mg/kg, xylazine 0.125 mg/kg, butorphanol 0.2 mg/kg intravenously as premedication and the ultrashort acting anaesthetics alfaxalone or propofol for inducing and maintaining in dogs with medically stabilised mitral valve regurgitation. Seven client-owned dogs with a second stage cardiac insufficiency were used in this study. All the dogs suffered from class II cardiac insufficiency according to the classification by the International Small Animal Cardiac Health Council (ISACH). All the dogs were treated with angiotensin converting enzyme inhibitors (enalapril) and diuretics (furosemide), which eliminated the clinical signs of mitral valve regurgitation in all the dogs included in the study. This was a prospective controlled clinical study, 12 months in duration, when the dogs included in the study underwent regular dental prophylaxis. The dogs were monitored electrocardiographically throughout the anaesthesia for the presence of arrhythmias, % oxygen saturation of haemoglobin (%SpO<sub>2</sub>) measured by pulse oximetry, heart rate, respiratory rate and body temperature. The dogs underwent two anaesthesia procedures with an interval of one year due to the prophylaxis of periodontitis, with the first anaesthesia maintained by propofol and second one by alfaxalone. The respiratory rate was mostly significantly higher in the individuals undergoing alfaxalone anaesthesia (P < 0.05), but neither the slower respiratory frequency in the propofol anaesthesia had any negative impact on the % oxygen saturation of the haemoglobin (%SpO<sub>2</sub>). The heart frequency was significantly higher in the alfaxalone group (P < 0.005). The arterial blood pressures were comparable, but, on the contrary, the two dogs from propofol group had significantly higher blood pressure. The cardiovascular values in both types of anaesthesia had a tendency to progressively decrease within the physiological range. The level of the analgesia was significantly higher in the case of the propofol anaesthesia (P < 0.01) and the recovery period was also significantly shorter (P < 0.005). It can be concluded that the investigated ultra short acting anaesthetics used in balanced anaesthesia containing subanaesthetic doses of xylazine can be used over one hour of surgical procedures in dogs stabilised for mitral valve regurgitation without a significantly increased risk from the anaesthesia.

Endothelial-Dependent and Independent Vascular Relaxation Effect of Tetrahydropalmatine on Rat Aorta.

Tetrahydropalmatine (THP) is an active natural alkaloid isolated from Corydalis yanhusuo W.T. Wang which has been widely used for treating pain and cardiovascular disease in traditional Chinese medicine. Previous studies suggested THP have various pharmacological effects in neural and cardio tissue while the vascular reactivity of THP was not fully established. The present study found that THP relaxed rat aorta which contracted by phenylephrine (Phe), KCl, and U46619. The vascular relaxation effect of THP was partially attenuated by PI3K inhibitor wortmannin, Akt inhibitor IV, endothelial nitric oxide synthetase (eNOS) inhibitor L-NAME, guanylate cyclase inhibitors and the mechanical removal of endothelium. Also, the eNOS substrate L-arginine reversed the inhibition effect of L-NAME on THP-induced vascular relaxation. THP also induced intracellular NO production in human umbilical vein endothelial cells. However, Pre-incubation with β-adrenergic receptor blocker propranolol, angiotensin II receptor 1 (AT1) inhibitor losartan, angiotensin II receptor 2 (AT1) inhibitor PD123319 or angiotensin converting enzyme inhibitor enalapril enhanced the vascular relaxation effect of THP. THP did not affect the angiotensin II induced vascular contraction. Cyclooxygenase-2 (COX2) inhibitor indomethacin did not affect the vascular relaxation effect of THP. Furthermore, pre-treatment THP attenuated KCl and Phe induced rat aorta contraction in standard Krebs solution. In Ca2+ free Krebs solution, THP inhibited the Ca2+ induced vascular contraction under KCl or Phe stress and reduced KCl stressed Ca2+ influx in rat vascular smooth muscle cells. THP also inhibited intracellular Ca2+ release induced vascular contraction by blocking Ryr or IP3 receptors. In addition, the voltage-dependent K+ channel (Kv) blocker 4-aminopyridine, ATP-sensitive K+ channel (KATP) blocker glibenclamide and inward rectifying K+ channel blocker BaCl2 attenuated THP induced vascular relaxation regardless of the Ca2+-activated K+ channel (KCa) blocker tetraethylammonium. Thus, we could conclude that THP relaxed rat aorta in an endothelium-dependent and independent manner. The underlying mechanism of THP relaxing rat aorta involved PI3K/Akt/eNOS/NO/cGMP signaling path-way, Ca2+ channels and K+ channels rather than COX2, β-adrenergic receptor and renin-angiotensin system (RAS). These findings indicated that THP might be a potent treatment of diseases with vascular dysfunction like hypertension.

A mouse model of heart failure exhibiting pulmonary edema and pleural effusion: Useful for testing new drugs

Introduction: Mouse models of chronic heart failure (HF) have been widely used in HF research. However, the current HF models most often use the C57BL/6 mouse strain and do not show the clinically relevant characteristics of pulmonary congestion. In this study, we developed a robust mouse model of HF in the BALB/c mouse strain, exhibiting pulmonary edema and pleural effusion, and we validated the model using the standard pharmacological therapies in patients with chronic HF and reduced ejection fraction (HFrEF) or acute decompensated HF.Methods: After induction of myocardial infarction (MI) by permanent ligation of the left coronary artery in BALB/c mice, the cardiac function, pulmonary congestion, disease biomarkers, and survival were evaluated using the angiotensin converting enzyme inhibitor enalapril or the loop diuretic furosemide. Enalapril was administered 4 weeks post-MI for 6 weeks or furosemide was given 10 weeks post-MI for 4 days, when pulmonary congestion was evident.Results: Compared to sham controls, MI mice developed systolic dysfunction, exhibited lung weight increase at 4 weeks, and progressively developed pleural effusion (60% of the animals) at 10 weeks. Compared to the vehicle, enalapril significantly reduced the lung weight and pleural effusion, preserved systolic function, and improved survival. Furthermore, furosemide completely abolished the pleural effusion. Enalapril or furosemide also reduced the plasma brain natriuretic peptide concentration.Discussion: The post-MI HF in BALB/c mice shows reproducible and robust pulmonary congestion and may be a clinically relevant model for novel drug testing for treatment in patients with HFrEF or acute decompensated HF.

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.

Role of ACE inhibitors in anthracycline-induced cardiotoxicity: A randomized, double-blind, placebo-controlled trial.

Several measures including drugs have been tried to reduce anthracycline cardiotoxicity. The lack of randomized trials prompted this study to assess the role of an angiotensin converting enzyme (ACE) inhibitor (enalapril) in anthracycline-induced cardiotoxicity in children with hematological malignancies. A randomized, double-blind, placebo-controlled trial was conducted on 84 patients with leukemia (41) and lymphoma (43) who received anthracyclines (doxorubicin and/or daunorubicin) at cumulative dose ≥200mg/m2 . The patients were randomized to receive either enalapril [group A (n=44)] or placebo [group B (n=40)] for 6months. Left ventricular ejection fraction (LVEF) and cardiac biomarkers (cardiac troponin I [cTnI], probrain natriuretic peptide [proBNP], and creatine kinase MB [CK-MB]) were assessed at baseline and 6months. The primary outcome was a measured decrease in LVEF (≥20%). Secondary outcome measures were changes in cardiac biomarkers and the development of heart failure or arrhythmias. LVEF decreased in both groups at 6months, more so in group B (62.25±5.49vs 56.15±4.79, P<0.001). A ≥20% decrease was seen in 3 patients in group B but none in group A (P=0.21). Cardiac biomarkers increased more in group B at 6months, and the increase was significant for proBNP (49.60±35.97vs 98.60±54.24, P<0.001) and cTnI (0.01±0.00vs 0.011±0.003, P=0.035) but not significant for CK-MB (1.08±0.18vs 1.21±0.44, P=0.079). In group A, 9.1% of the patients showed an increase in proBNP level ≥100 compared with 37.5% in group B (P<0.001). No patient developed heart failure or arrhythmia. Enalapril has a role in reducing cardiac toxicity after anthracycline administration.

Impact of Exercise Training and Enalapril, either alone or in Combination, on White Adipose Tissue Renin‐Angiotensin System in a Diet‐Induced Obesity Model

The renin–angiotensin system (RAS) has emerged as a regulator of metabolic homeostasis with angiotensin (Ang) II acting as an ‘adiposity signal’ and Ang 1–7 promoting counter‐regulatory effects. Chronic endurance training profoundly affects white adipose tissue (WAT) metabolism and causes remarkable changes in its RAS. In this context, the aim of this study was to evaluate the effects of endurance training and the angiotensin converting enzyme (ACE) inhibitor enalapril on WAT RAS and adiposity in a diet‐induced obesity mouse model. C57BL/6 mice were fed either standard chow (SC) or high‐fat (HF) diets for 16 weeks. After 8 weeks, HF‐fed animals were divided into 4 groups (n=8): HF, HF + Enalapril (HF‐E), HF + training (HF‐T) and HF + Enalapril + training (HF‐ET). Endurance training consisted of 60 min/day, 5 days/week moderate‐intensity treadmill running. Enalapril (10 mg/kg/day) was administered in the diet. Both interventions were maintained for 8 weeks. We assessed body mass (BM) and composition by DEXA, systolic blood pressure (SBP), lipid and inflammatory profile, circulating irisin, and WAT histology. WAT RAS components were measured by HPLC‐DAD. In comparison to SC animals, BM significantly increased in HF animals, but not in mice subjected to HF‐E and HF‐T interventions, whereas BM was significantly reduced in the HF‐ET group. SBP, adipocyte hypertrophy, adiposity index, and percentage body fat were all elated in HF compared to SC mice; however, the interventions prevented these elevations. Circulating cholesterol levels increased in the HF and HF‐E groups, whereas in the HF‐T and HF‐ET this variable did not differ from the SC group. IL‐6 and TNF‐α were significantly elevated by HF diet, and all interventions reduced circulating levels of these inflammatory markers to values similar to those of SC mice. Plasma irisin was increased only in endurance‐trained mice. WAT Ang II concentration was higher in the HF than SC group and all interventions reduced it. The HF‐ET group showed the lowest Ang II concentration compared to the other groups. The Ang II/Ang 1–7 WAT ratio in HF‐E and HF‐T was similar to the SC mice, whereas in the HF‐ET this ratio was significantly lower than SC and HF groups. The results of this study suggest that enalapril combined with endurance training has better results than either treatment alone in reducing adiposity and shifting the balance of RAS toward the Ang 1–7 counter‐regulatory axis in WAT. Furthermore, both enalapril and endurance training improved the inflammatory profile, although only endurance training reduced cholesterol and increased irisin levels. These results suggest that targeting WAT RAS could be a new therapeutic approach to treat obesity‐related dysfunctional metabolic alteration.Support or Funding InformationFAPERJ, CAPES and CNPqThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Transforming growth factor-β1 induces cerebrovascular dysfunction and astrogliosis through angiotensin II type 1 receptor-mediated signaling pathways.

Transgenic mice constitutively overexpressing the cytokine transforming growth factor-β1 (TGF-β1) (TGF mice) display cerebrovascular alterations as seen in Alzheimer's disease (AD) and vascular cognitive impairment and dementia (VCID), but no or only subtle cognitive deficits. TGF-β1 may exert part of its deleterious effects through interactions with angiotensin II (AngII) type 1 receptor (AT1R) signaling pathways. We test such interactions in the brain and cerebral vessels of TGF mice by measuring cerebrovascular reactivity, levels of protein markers of vascular fibrosis, nitric oxide synthase activity, astrogliosis, and mnemonic performance in mice treated (6 months) with the AT1R blocker losartan (10 mg/kg per day) or the angiotensin converting enzyme inhibitor enalapril (3 mg/kg per day). Both treatments restored the severely impaired cerebrovascular reactivity to acetylcholine, calcitonin gene-related peptide, endothelin-1, and the baseline availability of nitric oxide in aged TGF mice. Losartan, but not enalapril, significantly reduced astrogliosis and cerebrovascular levels of profibrotic protein connective tissue growth factor while raising levels of antifibrotic enzyme matrix metallopeptidase-9. Memory was unaffected by aging and treatments. The results suggest a pivotal role for AngII in TGF-β1-induced cerebrovascular dysfunction and neuroinflammation through AT1R-mediated mechanisms. Further, they suggest that AngII blockers could be appropriate against vasculopathies and astrogliosis associated with AD and VCID.

Новые возможности фармакотерапии у пациентов, страдающих хронической сердечной недостаточностью

In this article we have described clinical pharmacology and data of clinical studies of an innovational drug valsartan + sacubitril in patients with chronic heart failure (CHF). The use of supramolecular complex valsartan + sacubitril allows to elevate quality of life and improve prognosis of patients with CHF. High efficacy of valsartan+sacubitril relative to impact on composite primary end-point (cardiovascular death + hospitalization due to CHF) was demonstrated in the clinical trial PARADIGM-HF in which it was compared with angiotensin converting enzyme inhibitor enalapril. Advantages of the use of valsartan + sacubitril for the budget were demonstrated in pharmacoeconomic studies. These advantages are maximally realized at long-term administration. Cost-efficacy of the use of valsartan+sacubitril in pharmacotherapy of CHF is comparable with that of statins in the treatment of ischemic heart disease or implantation of a cardioverter-defibrillator in prevention of sudden cardiac death. Thus, introduction of the drug into practice can be expected to reduce budget expenditures.

Dynamic Changes in the Renin-Angiotensin-Aldosterone System and the Beneficial Effects of Renin-Angiotensin-Aldosterone Inhibitors on Spatial Learning and Memory in a Rat Model of Chronic Cerebral Ischemia.

Renin-angiotensin-aldosterone system (RAAS) plays an important role in the regulation of blood pressure and brain function. Therefore, we studied the dynamic changes in the RAAS in the blood, cerebral cortex, and hippocampus and the effects of RAAS inhibitors on spatial learning and memory and hippocampal apoptosis in a rat model of chronic cerebral ischemia (CCI) established by bilateral ligation of the common carotid arteries of rats. The levels of renin, angiotensin II (Ang II), and aldosterone (ALD) in the plasma, and the homogenates of the left side of cerebral cortex and whole hippocampus of rats were detected on day 1, 3, 7, 14, 21, and 30 by radioimmunoassay. Spatial learning and memory and hippocampal apoptosis were evaluated on day 30 by Morris water maze test (navigation and space exploration tests) and terminal dexynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) assay, respectively, after rats were orally administered with distilled water (DW), renin inhibitor aliskiren (30 mg/kg), Ang converting enzyme inhibitor enalapril (4 mg/kg), or Ang II receptor antagonist candesartan (2 mg/kg) daily for 30 days. The results showed that the levels of renin and Ang II were significantly higher but ALD fluctuated in the blood, cerebral cortex, and hippocampus in CCI rats compared to normal rats. However, aliskiren and enalapril could significantly decrease (p < 0.05) the levels of renin, Ang II and ALD in the blood, cerebral cortex, and hippocampus compared to DW treatment; while candesartan had similar effect on renin and ALD but no effect on Ang II in CCI rats. Furthermore, spatial learning and memory were significantly decreased but apoptosis in the hippocampus was obviously increased in CCI rats compared to normal rats (p < 0.05). However, aliskiren, enalapril, and candesartan were equally effective to improve spatial learning and memory and decrease apoptosis in the hippocampus. Therefore, RAAS plays an important role in the development of cerebral ischemia and RAAS inhibitors aliskiren, enalapril, and candesartan improve spatial learning and memory and protect brain injury by inhibiting hippocampal apoptosis in CCI rats.

High-throughput quantification of 8 antihypertensive drugs and active metabolites in human plasma using UPLC-MS/MS.

To assess drug adherence of patients with hypertension, an analytical method was developed and validated using ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The method includes eight frequently prescribed antihypertensive drugs from four classes and their active metabolites: angiotensin converting enzyme inhibitors enalapril and perindopril (active metabolites respectively enalaprilate and perindoprilate), angiotensin II receptor blockers losartan (with the active metabolite losartan carboxylic acid) and valsartan, calcium channel blockers amlodipine and nifedipine and diuretics hydrochlorothiazide and spironolactone (with the active metabolite canrenone). The antihypertensive drugs were analyzed using a simple and fast sample preparation protocol with protein precipitation followed by chromatographic separation using a gradient elution on a reversed phase column. Mass spectrometric detection was conducted by applying both positive and negative electrospray ionization (ESI+/ESI-) and selected reaction monitoring mode (MS/MS). Only 50μl of plasma sample is needed for the simultaneous quantification of all 12 compounds within 6min run-to-run analysis time. Enalapril-d5 was applied as internal standard for all compounds except hydrochlorothiazide (internal standard: Hydrochlorothiazide-13C,d2). The method was validated according to FDA guidelines. Matrix effects were examined using the method of Matuszewski. Correlation coefficients were higher than 0.995 for all compounds. Intra- and inter-day accuracies were <15% for all analytes except spironolactone (-16.8%) in the established linear range. Intra- and inter-day precision were <15% for all analytes. As a result of the lower sensitivity of hydrochlorothiazide, the lowest three calibration levels were excluded. The described method is suitable for the simultaneous quantitative analysis of the most commonly used antihypertensive drugs and their corresponding active metabolites. Major advantages are minimal sample volume and clean up and a short runtime. The method is now available to monitor drug adherence of patients with resistant hypertension in our hospital.

RETRACTED: Association of angiotensin II receptor 1 and lectin-like oxidized low-density lipoprotein receptor-1 mediates the cardiac hypertrophy induced by oxidized low-density lipoprotein

To date the molecular mechanism of cardiac hypertrophy has not been completely elucidated. Since oxidized low-density lipoprotein (ox-LDL) is considered a risk marker for early ventricular remodeling, we speculated that ox-LDL may be related to cardiac hypertrophy. We observed the significantly upregulation of plasma ox-LDL and hypertrophic responses, such as cardiomyocyte size and specific gene expressions in Apo E-/- mice fed with high fat diet, accompanied by the upregulation of AT1-R and lectin-like oxidized low-density protein receptor 1 (LOX-1). Ox-LDL treatment with neonatal rat cardiomyocyte for 24h significantly induced similar hypertrophic responses and also upregulation of AT1-R and LOX-1. The analysis of co-immunoprecipitation and the bimolecular fluorescence complementation assay proved that LOX-1 and AT1-R could directly bind together in the presence of ox-LDL, suggesting a critical role of the association between LOX-1 and AT1-R in ox-LDL-induced cardiac hypertrophy. Furthermore, we found that the AT1-R blocker Losartan and LOX-1 neutralizing antibody through inhibiting AT1-R or LOX-1 could both decline ox-LDL-induced hypertrophic responses whereas angiotensin converting enzyme inhibitor Enalapril only partially inhibited the responses stimulated by ox-LDL. These findings suggested that ox-LDL could induce cardiac hypertrophy through the direct association of AT1-R and LOX-1.

Possible Augmentive Effect of Antioxidant Vitamin C in Patients with Essential Hypertension Treated with Amlodipin or Enalapril

Hypertension is identified as one of the most significant risk factors for cardiovascular diseases (CVDs). There is growing evidence showing that oxidative stress plays a major role in hypertension. Increased production of reactive oxygen species and decrease bioavailability of antioxidant have been demonstrated in experimental and human hypertension. The present study was directed to determine the beneficial effect of the antioxidant vitamin C in patients with essential hypertension treated with the calcium channel blocker (amlodipine) or with the angiotensin converting enzyme inhibitor (enalapril). Ninety six patients (50 females and 46 males) with essential hypertension and treated with amlodipine or enalapril, age (50.43 ± 0.55 year) were participated in this study and divided in to: Twenty five patients received amlodipine 5mg tablet once daily (group 1), twenty five patients received the same dose of amlodipine plus 500mg of vitamin C tablet twice daily (group 2), twenty three patients received enalapril 5 mg tablet once daily (group 3), and twenty three patients received the same dose of enalapril plus 500mg of vitamin C tablet twice daily (group 4). Twenty apparently healthy subjects (11 females and 9 males) also participated in this study as control group (group 5). All patients were treated and followed up for one month. The mean blood pressures were measured for each patient before treatment and one, two, three and four weeks after treatment. Serum malondialdehyde (MDA), lipid profile, electrocardiogram (ECG) parameters and heart rate were measured for each patient before treatment and two and four weeks after treatment. The addition of vitamin C to amlodipine or enalapril treated patients had resulted in a significant (p&lt;0.05) lowering effect on mean blood pressure after two, three and four weeks. On the other hand, the addition of vitamin C to amlodipine or enalapril treated patients had resulted in a significant lowering of serum MDA after two and four weeks of treatment. While there was no significant change in lipid profile or ECG parameters and heart rate of patients in group two and four after two and four weeks of vitamin C treatment as compared to their values at zero time and to patients in group one and three respectively. The study indicates that oxidative stress may have a significant role in essential hypertension, and addition of the antioxidant vitamin C to antihypertensive drugs used in this study can give a good blood pressure lowering effect and good protection against lipid peroxidation.&#x0D; Key words: Antioxidant ,Vitamin C, Essential Hypertension, Amlodipin , Enalapril

Sacubitril/Valsartan: A Review in Chronic Heart Failure with Reduced Ejection Fraction.

Sacubitril/valsartan (Entresto™; LCZ696) is an orally administered supramolecular sodium salt complex of the neprilysin inhibitor prodrug sacubitril and the angiotensin receptor blocker (ARB) valsartan, which was recently approved in the US and the EU for the treatment of chronic heart failure (NYHA class II-IV) with reduced ejection fraction (HFrEF). In the large, randomized, double-blind, PARADIGM-HF trial, sacubitril/valsartan reduced the incidence of death from cardiovascular causes or first hospitalization for worsening heart failure (composite primary endpoint) significantly more than the angiotensin converting enzyme (ACE) inhibitor enalapril. Sacubitril/valsartan was also superior to enalapril in reducing death from any cause and in limiting the progression of heart failure. Sacubitril/valsartan was generally well tolerated, with no increase in life-threatening adverse events. Symptomatic hypotension was significantly more common with sacubitril/valsartan than with enalapril; the incidence of angio-oedema was low. Therefore, sacubitril/valsartan is a more effective replacement for an ACE inhibitor or an ARB in the treatment of HFrEF, and is likely to influence the basic approach to treatment.