Angiotensin-converting enzyme inhibitors

Pharmacologic Approaches to Electrolyte Abnormalities in Heart Failure

Electrolyte abnormalities are common in heart failure and can arise from a variety of etiologies. Neurohormonal activation from ventricular dysfunction, renal dysfunction, and heart failure medications can perturb electrolyte homeostasis which impact both heart failure-related morbidity and mortality. These include disturbances in serum sodium, chloride, acid-base, and potassium homeostasis. Pharmacological treatments differ for each electrolyte abnormality and vary from older, established treatments like the vaptans or acetazolamide, to experimental or theoretical treatments like hypertonic saline or urea, or to newer, novel agents like the potassium binders: patiromer and zirconium cyclosilicate. Pharmacologic approaches range from limiting electrolyte intake or directly repleting the electrolyte, to blocking or promoting their resorption, and to neurohormonal antagonism. Because of the prevalence and clinical impact of electrolyte abnormalities, understanding both the older and newer therapeutic options is and will continue to be necessity for the management of heart failure.

Bradykinin/B2 receptor activation regulates renin in M-1 cells via protein kinase C and nitric oxide

In the collecting duct (CD), the interactions of renin angiotensin system (RAS) and kallikrein-kinin system (KKS) modulate Na⁺ reabsorption, volume homeostasis, and blood pressure. In this study, we used a mouse kidney cortical CD cell line (M-1 cells) to test the hypothesis that in the CD, the activation of bradykinin B₂ receptor (B₂R) increases renin synthesis and release. Physiological concentrations of bradykinin (BK) treatment of M-1 cells increased renin mRNA and prorenin and renin protein contents in a dose-dependent manner and increased threefold renin content in the cell culture media. These effects were mediated by protein kinase C (PKC) independently of protein kinase A (PKA) because B₂R antagonism with Icatibant and PKC inhibition with calphostin C, prevented these responses, but PKA inhibition with H89 did not modify the effects elicited by the B₂R activation. BK-dependent stimulation of renin gene expression in CD cells also involved nitric oxide (NO) pathway because increased cGMP levels and inhibition of NO synthase with L-NAME prevented it. Complementary renin immunohistochemical studies performed in kidneys from mice with conventional B₂R knockout and conditional B₂R knockout in the CD, showed marked decreased renin immunoreactivity in CD, regardless of the renin presence in juxtaglomerular cells in the knockout mice. These results indicate that the activation of B₂R increases renin synthesis and release by the CD cells through PKC stimulation and NO release, which support further the interactions between the RAS and KKS.

Review of Top 10 Prescribed Drugs and Their Interaction with Dental Treatment

The proportion of people over age 60 is growing faster than any other group. Many patients take several medications to manage multiple chronic medical conditions. Poor oral health is common and dental visits by patients over the age of 65 are increasing. The dentist must recognize that these medications may interact with dental treatment. This article reviews the top 10 prescribed drugs as listed in the IMS Institute national prescription audit in January 2015 and reviews the interactions between these medications and dental treatment. The medications reviewed include levothyroxine, acetaminophen/hydrocodone, lisinopril, metoprolol, atorvastatin, amlodipine, metformin, omeprazole, simvastatin, and albuterol.

Elevated Plasma Aβ42 in Cognitively Impaired Individuals Taking ACE Inhibitor Antihypertensives

BACKGROUND/RATIONALE

Accumulating evidence suggests that the use of angiotensin-converting enzyme inhibitor (ACE-I) medication protects against cognitive decline in the elderly patients. We investigated whether ACE-I use was associated with higher plasma levels of amyloid-β (Aβ), possibly indicating improved Aβ clearance from brain to blood.

METHODS

We measured and compared plasma concentrations of Aβ42, Aβ40, and creatinine in cognitively impaired individuals with amnestic mild cognitive impairment, probable Alzheimer's disease (AD) dementia, and mixed probable AD/vascular dementia.

RESULTS

Plasma Aβ42 levels and Aβ42/Aβ40 ratios of participants taking ACE-Is (n = 11) significantly exceeded ( t = 3.1, df = 19, P = .006; U = 24, P = .029, respectively) those not taking ACE-Is (n = 10).

CONCLUSIONS

This study is the first to show an association between ACE-I use and increased plasma Aβ42 level and Aβ42/Aβ40 ratio in cognitively impaired individuals. Future investigations should assess whether a possible ACE-I-induced increase in plasma Aβ42 indicates improved Aβ42 clearance from brain that contributes to protection from cognitive decline.

Novel Therapies for Acute Kidney Injury

Acute kidney injury (AKI) is a common disease with a complex pathophysiology. The old paradigm of identifying renal injury based on location-prerenal, intrarenal, and postrenal-is now being supplanted with a new paradigm based on observable kidney injury patterns. The pathophysiology of AKI on a molecular and microanatomical level includes inflammation, immune dysregulation, oxidative injury, and impaired microcirculation. Treatment has traditionally been supportive, including the avoidance of nephrotoxins, judicious volume and blood pressure management, hemodynamic monitoring, and renal replacement therapy. Fluid overload and chloride-rich fluids are now implicated in the development of AKI, and resuscitation with a balanced, buffered solution at a conservative rate will mitigate risk. Novel therapies, which address specific observable kidney injury patterns include direct oxygen-free radical scavengers such as α-lipoic acid, curcumin, sodium-2-mercaptoethane sulphonate, propofol, and selenium. In addition, angiotensin II and adenosine receptor antagonists hope to ameliorate kidney injury via manipulation of renal hemodynamics and tubulo-glomerular feedback. Alkaline phosphatase, sphingosine 1 phosphate analogues, and dipeptidylpeptidase-4 inhibitors counteract kidney injury via manipulation of inflammatory pathways. Finally, genetic modifiers such as 5INP may mitigate AKI via transcriptive processes.

The Consumption of Dairy Products Is Associated with Reduced Risks of Obesity and Metabolic Syndrome in Korean Women but not in Men

We aimed to investigate the association between dairy product consumption and the risk of obesity and metabolic syndrome (MetS) in Korean adults. Data from 13,692 Korean adults aged ≥19 years from the KNHANES 2010–2013 were used. The study participants were divided into three groups according to the serving size of dairy products they consumed based on a single 24-h recall. About 58% of the Korean adults did not consume any dairy products in one day. In both the sexes, only those who adhered to the recommendation for dairy products (≥1 serving/day) achieved the daily requirement of calcium. Women who consumed ≥1 serving/day of dairy products had lower risks of obesity (body mass index ≥ 25 kg/m²) (adjusted odds ratio (AOR), 0.77; 95% confidence interval (CI), 0.66–0.89; p for trend < 0.01) and MetS (AOR, 0.67; 95% CI, 0.56–0.80; p for trend < 0.01) than women who did not consume dairy products. However, these significant associations were not observed in men. In conclusion, consuming ≥ 1 serving/day of dairy products could be an easy and efficient strategy for meeting daily calcium requirement as well as lowering risks of obesity and MetS among Korean women.

Translation of Angiotensin-Converting Enzyme 2 upon Liver- and Lung-Targeted Delivery of Optimized Chemically Modified mRNA

Changes in lifestyle and environmental conditions give rise to an increasing prevalence of liver and lung fibrosis, and both have a poor prognosis. Promising results have been reported for recombinant angiotensin-converting enzyme 2 (ACE2) protein administration in experimental liver and lung fibrosis. However, the full potential of ACE2 may be achieved by localized translation of a membrane-anchored form. For this purpose, we advanced the latest RNA technology for liver- and lung-targeted ACE2 translation. We demonstrated in vitro that transfection with ACE2 chemically modified messenger RNA (cmRNA) leads to robust translation of fully matured, membrane-anchored ACE2 protein. In a second step, we designed eight modified ACE2 cmRNA sequences and identified a lead sequence for in vivo application. Finally, formulation of this ACE2 cmRNA in tailor-made lipidoid nanoparticles and in lipid nanoparticles led to liver- and lung-targeted translation of significant amounts of ACE2 protein, respectively. In summary, we provide evidence that RNA transcript therapy (RTT) is a promising approach for ACE2-based treatment of liver and lung fibrosis to be tested in fibrotic disease models.

Nutritional and Functional Bioactivity Value of Selected Azorean Macroalgae: Ulva compressa, Ulva rigida, Gelidium microdon, and Pterocladiella capillacea

This study presents information on the biochemical composition (dry weight basis), nutritional aspects, and angiotensin I-converting enzyme (ACE) inhibitory properties of selected macroalgae (Ulva compressa, Ulva rigida, Gelidium microdon, and Pterocladiella capillacea) from Azores. Moisture content was very high (83.2% to 90.0% of fresh weight). Total dietary fiber (33.7% to 41.0%) that presented a good balance of both soluble and insoluble fibers (15.5% to 19.2% and 18.2% to 21.8%, respectively) was the most abundant component in these macroalgae. Protein and ash (ranged from 15.7% to 23.4% and 10.7% to 20.7%, respectively) were the 2nd most abundant components in red and green macroalgae, respectively. Moderate soluble carbohydrate contents (14.5% to 19.8%) were found in all species. Lipid contents were low (1.0% to 4.3%), particularly in Ulva species (1.0% to 1.7%), but contained higher unsaturated fatty acids (FAs) (7.5% to 32.9% and 29.6% to 69.2% of total FA for monounsaturated fatty acid and polyunsaturated fatty acid groups, respectively) than saturated fatty acid (23.3% to 46.8% of total FA) contents. All the macroalgal proteins had high digestibility in vitro (82.2% to 89.4%, relatively to sodium caseinate), contained high quantity of essential amino acids (45.3% to 58.1% of total amino acids), but in different proportions, and were rich in aspartic and glutamic acids that together account for 17.2% to 36.2% of the total amino acids. These results suggested that regular consumption of the selected macroalgae may improve human health and revealed that they can be used for producing food supplements for human and animal nutrition and/or pharmaceuticals with potential effect on the regional economy. Furthermore, the ACE-inhibitory IC₅₀ values of 0.095 to 0.695 mg/mL for the <1 kDa protein hydrolysate fraction revealed a potential impact on hypertension disorder.

Beneficial Effects of Renin-Angiotensin System Blockers on Testicular Morphology

Background: The renin-angiotensin system (RAS) is a set of peptides, enzymes, and receptors specially involved in the control of extracellular fluid volume and blood pressure (BP); however, some of its components have already been identified in the testis, such as angiotensinogen, angiotensin converting enzyme, and renin. Objectives: The aim of this study was to evaluate whether renin-angiotensin system blockers have effects on the testicular morphology of animals fed a high energy density (HED) diet. Materials and Methods: Male C57BL/6 mice were fed initially a standard chow (SC) or a HED diet. After 8 weeks, HED animals were randomized into 4 groups, each group receiving one of the following treatments for the next 6 weeks: HED-A: aliskiren (50 mg/kg/d); HED-E: enalapril (30 mg/kg/d); HED-L: losartan (10 mg/kg/d); and untreated HED group. The BP was measured biweekly. At the end of treatment, all animals were killed and the testes were processed for morphometric and stereological parameters including density of seminiferous tubules per area, density of length and the total length of the seminiferous tubules, height of the epithelium, and diameter of the seminiferous tubules. Samples were tested for their homoscedasticity and the differences between the groups were tested by one-way analysis of variance (ANOVA), followed by the Holm-Sidak post-test. In all cases, the significance level adopted was P ≤ .05. Results: Compared to SC, HED groups presented an increase in BP, normalized by all RAS blockers. However, the HED diet caused testis alterations that were not affected by aliskiren or losartan. Only enalapril maleate was capable of reversing such alterations. Conclusions: Further studies are still needed to answer why only enalapril was able to reveal the morphological changes caused by the high energy diet; so enalapril could be suggested as the drug of choice for patients with previous reproductive dysfunction.

Effects of tryptophan-containing peptides on angiotensin-converting enzyme activity and vessel tone ex vivo and in vivo

PURPOSE

Over-activation of the renin-angiotensin axis and worsening of vascular function are critical contributors to the development of hypertension. Therefore, inhibition of angiotensin-converting enzyme (ACE), a key factor of the renin-angiotensin axis, is a first line treatment of hypertension. Besides pharmaceutical ACE inhibitors, some natural peptides have been shown to exert ACE-inhibiting properties with antihypertensive effects and potentially beneficial effects on vascular function. In this study, the ACE-inhibiting potential and effects on vascular function of tryptophan-containing peptides were evaluated.

METHODS

The ACE inhibitory action and stability of tryptophan-containing peptides was tested in endothelial cells-a major source of whole body ACE activity. Furthermore, the efficacy of peptides on vascular ACE activity, as well as vessel tone was assessed both ex vivo and in vivo.

RESULTS

In human umbilical vein endothelial cells (HUVEC), isoleucine-tryptophan (IW) had the highest ACE inhibitory efficacy, followed by glutamic acid-tryptophan (EW) and tryptophan-leucine (WL). Whereas none of the peptides affected basal vessel tone (rat aorta), angiotensin I-induced vasoconstriction was blocked. IW effectively inhibited aortic ACE activity ex vivo taken from SHRs after 14-weeks of oral treatment with IW. Furthermore, IW treated SHRs showed better endothelium-dependent vessel relaxation compared to placebo.

CONCLUSION

This study shows strong ACE-inhibiting effects of IW, EW and WL in HUVECs and aorta. The peptides effectively counteract angiotensin-induced vasoconstriction and preserve endothelium-dependent vessel relaxation. Thus, tryptophan-containing peptides and particularly IW may serve as innovative food additives with the goal of protection from angiotensin II-induced worsening of vascular function.

Recent Research in Antihypertensive Activity of Food Protein-derived Hydrolyzates and Peptides

Year to year obesity prevalence, reduced physical activities, bad habits/or stressful lifestyle, and other environmental and physiological impacts lead to increase in diseases such as coronary heart disease, stroke, cancer, diabetes, and hypertension worldwide. Hypertension is considered as one of the most common serious chronic diseases; however, discovery of medications with high efficacy and without side effects for treatment of patients remains a challenge for scientists. Recent trends in functional foods have evidenced that food bioactive proteins play a major role in the concepts of illness and curing; therefore, nutritionists, biomedical scientists, and food scientists are working together to develop improved systems for the discovery of peptides with increased potency and therapeutic benefits. This review presents a recent research carried out to date for the purpose of isolation and identification of bioactive hydrolyzates and peptides with angiotensin I converting enzyme inhibitory activity and antihypertensive effect from animal, marine, microbial, and plant food proteins. Effects of food processing and hydrolyzation conditions as well as some other impacts on formation, activity, and stability of these hydrolyzates and peptides are also presented.

Therapeutic efficacy and safety of ACE inhibitors in the hypertensive paediatric population: a review

PURPOSE

Since 1997, strong incentives have been introduced worldwide to improve access to safe and effective medicines addressing the therapeutic needs of children. ACE inhibitors, the most prescribed antihypertensive drugs in the paediatric population, are one of the prototype drugs targeted by the legislation initiatives. Our purpose in assembling this review is to evaluate and describe the current evidence for the efficacy and safety profile of ACE inhibitors in the paediatric population.

METHODS

The authors made a descriptive review of the literature from 1980 to 2015 using the following search terms: hypertension, child, paediatric, ACE (inhibitors), renin-angiotensin aldosterone system, captopril, lisinopril, enalapril, ramipril and fosinopril.

RESULTS

A total of 16 studies evaluating efficacy and safety of ACE inhibitors were included in this review. The included studies demonstrate that ACE inhibitors have the potency to decrease the systolic and/or diastolic blood pressure with an overall favourable safety profile in a short-term period. More importantly, the incentives resulted in an improvement of the overall availability of paediatric labelling, dosing and safety information for ACE inhibitors. However, they failed to fulfil several of paediatric needs: absence of long-term safety data on growth and maturation, absence of commercially available child-friendly formulations and incomplete evaluation of the entire paediatric hypertension population.

CONCLUSION

Additional efforts are needed to close the gap between the availability of drugs that are labelled and indicated for paediatric use and the actual drug usage in children, especially in young children, neonates and children with severe hypertension, renal transplantation or severe renal impairment.

Chronic enalapril treatment increases transient outward potassium current in cardiomyocytes isolated from right ventricle of spontaneously hypertensive rats

It has been well established that chronic pressure overload resulting from hypertension leads to ventricular hypertrophy and electrophysiological remodeling. The transient outward potassium current (I _to) reduction described in hypertensive animals delays ventricular repolarization, leading to complex ventricular arrhythmias and sudden death. Antihypertensive drugs, as angiotensin-converting enzyme inhibitors (ACEi), can restore I _to and reduce the incidence of arrhythmic events. The purpose of this study was to evaluate the differential effects of long-term treatment with ACEi or direct-acting smooth muscle relaxant on the I _to of left and right ventricle myocytes of spontaneously hypertensive rats (SHR). Animals were divided into four groups: normotensive Wistar-Kyoto rats (WKY), hypertensive (SHR), SHR treated for 6 weeks with enalapril 10 mg/kg/day (SHRE), or hydralazine 20 mg/kg/day (SHRH). Systolic blood pressure (SBP) and hypertrophy index (heart weight/body weight (HW/BW)) were determined at the end of treatment period. Cell membrane capacitance (C _m) and I _to were assessed in cardiomyocytes isolated from left and right ventricles. The SHR exhibited significantly increased SBP and HW/BW when compared to the WKY. The treated groups, SHRE and SHRH, restored normal SBP but not HW/BW. The SHR group exhibited a diminished I _to in the left but not the right ventricle. Both the treated groups restored I _to in the left ventricle. However, in the right ventricle, only enalapril treatment modified I _to. The SHRE group exhibited a significant increase in I _to compared to all the other groups. These findings suggest that enalapril may increase I _to by a pressure overload independent mechanism.

Binding of ACE-inhibitors to in vitro and patient-derived amyloid-β fibril models

Currently, no drugs exist that can prevent or reverse Alzheimer's disease, a neurodegenerative disease associated with the presence, in the brain, of plaques that are composed of β-amyloid (Aβ) peptides. Recent studies suggest that angiotensin-converting enzyme (ACE) inhibitors, a set of drugs used to treat hypertension, may inhibit amyloid formation in vitro. In the present study, we investigate through computer simulations the binding of ACE inhibitors to patient-derived Aβ fibrils and contrast it with that of ACE inhibitors binding to in vitro generated fibrils. The binding affinities of the ACE inhibitors are compared with that of Congo red, a dye that is used to identify amyloid structures and that is known to be a weak inhibitor of Aβ aggregation. We find that ACE inhibitors have a lower binding affinity to the patient-derived fibrils than to in vitro generated ones. For patient-derived fibrils, their binding affinities are even lower than that of Congo red. Our observations raise doubts on the hypothesis that these drugs inhibit fibril formation in Alzheimer patients by interacting directly with the amyloids.

Angiotensin-converting enzyme inhibitors and receptor blockers in heart failure and chronic kidney disease - Demystifying controversies

In clinical setting, congestive heart failure (CHF) and chronic kidney disease (CKD) often co-exist in patients due to common underlying predisposing factors. An intricate equilibrium between the cardiovascular and renal system is maintained through rennin angiotensin–aldosterone axis and autonomic nervous system. Consequent to favorable hemodynamic modification, angiotensin converting enzyme inhibitors (ACEI) and angiotensin receptor blocking (ARB) therapy have proven to be an indispensable aspect of heart failure management with morbidity and mortality benefit. Additionally, progression to end stage renal failure may be halted by renin angiotensin aldosterone system (RAAS) blockade in patients with preexisting renal dysfunction. However, concern over the safety of RAAS blockade in presence of renal impairment has led to profound underutilization of these drugs in CHF patients with renal insufficiency. This review aims to provide a simplified guide to pathophysiology and management options of this perplexing situation.

A Review of Potential Marine-derived Hypotensive and Anti-obesity Peptides

Bioactive peptides are food derived components, usually consisting of 3-20 amino acids, which are inactive when incorporated within their parent protein. Once liberated by enzymatic or chemical hydrolysis, during food processing and gastrointestinal transit, they can potentially provide an array of health benefits to the human body. Owing to an unprecedented increase in the worldwide incidence of obesity and hypertension, medical researchers are focusing on the hypotensive and anti-obesity properties of nutritionally derived bioactive peptides. The role of the renin-angiotensin system has long been established in the aetiology of metabolic diseases and hypertension. Targeting the renin-angiotensin system by inhibiting the activity of angiotensin-converting enzyme (ACE) and preventing the formation of angiotensin II can be a potential therapeutic approach to the treatment of hypertension and obesity. Fish-derived proteins and peptides can potentially be excellent sources of bioactive components, mainly as a source of ACE inhibitors. However, increased use of marine sources, poses an unsustainable burden on particular fish stocks, so, the underutilized fish species and by-products can be exploited for this purpose. This paper provides an overview of the techniques involved in the production, isolation, purification, and characterization of bioactive peptides from marine sources, as well as the evaluation of the ACE inhibitory (ACE-I) activity and bioavailability.

Role of cardiac renin angiotensin system in ischemia reperfusion injury and preconditioning of heart

Cardio-vascular diseases are the leading cause of morbidity and mortality. Ischemia is a state of oxygen deprivation in tissues, whereas reperfusion is restoration of blood flow in ischemic tissues. Myocardial damage of tissue during reperfusion after ischemic insult is known as myocardial ischemia–reperfusion (I/R) injury. It induces damage to cardiac muscle via increasing expression of oxygen, sodium and calcium ions which are responsible in the activation of proteases and cell death. Heart renin angiotensin system (RAS) plays an important role in the myocardial ischemia and reperfusion injury. Angiotensin (1–7) is responsible for vasodilation and angiotensin II for vasoconstriction. Here-in we reviewed how myocardial I/R injury sets in by up-regulation of angiotensin II that leads to increased infarct size, which can be reduced by the use of ACE inhibitors, ACE2 activators and angiotensin II antagonist.

Blood capillary rarefaction and lymphatic capillary neoangiogenesis are key contributors to renal allograft fibrosis in an ACE inhibition rat model

Chronic allograft fibrosis is the major cause of graft loss in kidney transplantation. Progression can only be reduced by inhibition of the renin-angiotensin system (RAS). We tested the hypothesis that the protection provided by angiotensin-converting enzyme (ACE) inhibition also decreases capillary rarefaction, lymphangiogenesis, and podocyte injury in allograft fibrosis. Fisher kidneys were transplanted into bilaterally nephrectomized Lewis rats treated with enalapril (60 mg/kg per day) (ACE inhibitor, ACEi) or vehicle. Proteinuria, blood urea nitrogen, and plasma creatinine were regularly assessed, and grafts were harvested for morphological and immunohistological analysis at various times up to 32 wk. In the vehicle group, many new lymphatic capillaries and severe and diffuse mononuclear infiltration of allografts were observed already 1 wk after transplantation. Lymphangiogenesis increased until week 4, by which time inflammatory infiltration became focal. Lymphatic capillaries were often located at sites of inflammation. Progressive interstitial fibrosis, glomerulosclerosis, capillary rarefaction, and proteinuria appeared later, at weeks 4-12 The number of lymphatic capillary cross sections strongly correlated with the interstitial fibrosis score. Podoplanin immunostaining, a marker of healthy podocytes, disappeared from inflamed or sclerotic glomerular areas. ACEi protected from lymphangiogenesis and associated inflammation, preserved glomerular podoplanin protein expression, and reduced glomerulosclerosis, proteinuria, tubulointerstitial fibrosis, and blood capillary rarefaction at 32 wk. In conclusion, ACEi considerably decreased and/or delayed both glomerulosclerosis and tubulointerstitial injury. Prevention of glomerular podoplanin loss and proteinuria could be attributed to the known intraglomerular pressure-lowering effects of ACEi. Reduction of lymphangiogenesis could contribute to amelioration of tubulointerstitial fibrosis and inflammatory infiltration after ACEi.

Mechanisms of triple whammy acute kidney injury

Pre-renal acute kidney injury (AKI) results from glomerular haemodynamic alterations leading to reduced glomerular filtration rate (GFR) with no parenchymal compromise. Renin-angiotensin system inhibitors, such as angiotensin-converting enzyme inhibitors (ACEIs), angiotensin receptor antagonists (ARAs), non-steroidal anti-inflammatory drugs (NSAIDs) and diuretics, are highly prescribed drugs that are frequently administered together. Double and triple associations have been correlated with increased pre-renal AKI incidence, termed "double whammy" and "triple whammy", respectively. This article presents an integrative analysis of the complex interplay among the effects of NSAIDs, ACEIs/ARAs and diuretics, acting alone and together in double and triple therapies. In addition, we explore how these drug combinations alter the equilibrium of regulatory mechanisms controlling blood pressure (renal perfusion pressure) and GFR to increase the odds of inducing AKI through the concomitant reduction of blood pressure and distortion of renal autoregulation. Using this knowledge, we propose a more general model of pre-renal AKI based on a multi whammy model, whereby several factors are necessary to effectively reduce net filtration. The triple whammy was the only model associated with pre-renal AKI accompanied by a course of other risk factors, among numerous potential combinations of clinical circumstances causing hypoperfusion in which renal autoregulation is not operative or is deregulated. These factors would uncouple the normal BP-GFR relationship, where lower GFR values are obtained at every BP value.

Empagliflozin and Progression of Kidney Disease in Type 2 Diabetes

BACKGROUND

Diabetes confers an increased risk of adverse cardiovascular and renal events. In the EMPA-REG OUTCOME trial, empagliflozin, a sodium-glucose cotransporter 2 inhibitor, reduced the risk of major adverse cardiovascular events in patients with type 2 diabetes at high risk for cardiovascular events. We wanted to determine the long-term renal effects of empagliflozin, an analysis that was a prespecified component of the secondary microvascular outcome of that trial.

METHODS

We randomly assigned patients with type 2 diabetes and an estimated glomerular filtration rate of at least 30 ml per minute per 1.73 m(2) of body-surface area to receive either empagliflozin (at a dose of 10 mg or 25 mg) or placebo once daily. Prespecified renal outcomes included incident or worsening nephropathy (progression to macroalbuminuria, doubling of the serum creatinine level, initiation of renal-replacement therapy, or death from renal disease) and incident albuminuria.

RESULTS

Incident or worsening nephropathy occurred in 525 of 4124 patients (12.7%) in the empagliflozin group and in 388 of 2061 (18.8%) in the placebo group (hazard ratio in the empagliflozin group, 0.61; 95% confidence interval, 0.53 to 0.70; P<0.001). Doubling of the serum creatinine level occurred in 70 of 4645 patients (1.5%) in the empagliflozin group and in 60 of 2323 (2.6%) in the placebo group, a significant relative risk reduction of 44%. Renal-replacement therapy was initiated in 13 of 4687 patients (0.3%) in the empagliflozin group and in 14 of 2333 patients (0.6%) in the placebo group, representing a 55% lower relative risk in the empagliflozin group. There was no significant between-group difference in the rate of incident albuminuria. The adverse-event profile of empagliflozin in patients with impaired kidney function at baseline was similar to that reported in the overall trial population.

CONCLUSIONS

In patients with type 2 diabetes at high cardiovascular risk, empagliflozin was associated with slower progression of kidney disease and lower rates of clinically relevant renal events than was placebo when added to standard care. (Funded by the Boehringer Ingelheim and Eli Lilly and Company Diabetes Alliance; EMPA-REG OUTCOME ClinicalTrials.gov number, NCT01131676.).

An Overview of Diabetic Nephropathy

Diabetic nephropathy is a complication of type 1 and type diabetes mellitus and the leading cause of end-stage renal disease in the United States. The health care system spends billions of dollars every year to treat end-stage renal disease patients. Health care providers must address diabetic nephropathy. The American Diabetes Association set forth recommendations for early detection to slow the progression of renal disease and treatment guidelines for patients with diabetes along with hypertension and diabetic nephropathy. Routine screening and treatment are the key to ending the trend of patients with diabetic nephropathy progressing to end-stage renal disease. Glycemic and blood pressure control is important for managing diabetic nephropathy. Angiotensinconverting enzyme inhibitors and angiotensin receptor blockers have become drugs of choice for treating diabetic nephropathy, based on clinical studies showing they slow the progression of renal disease. Whether protein restrictions are necessary in patients with diabetic nephropathy is being debated.

Tissue ACE Inhibitors for Secondary Prevention of Cardiovascular Disease in Patients With Preserved Left Ventricular Function: A Pooled Meta-analysis of Randomized Placebo-controlled Trials

Objective. A pooled meta-analysis of published, randomized placebo-controlled clinical trials to evaluate the role of tissue angiotensin-converting enzyme (ACE) inhibitors in secondary prevention of cardiovascular disease in patients with preserved left ventricular function. Sources. Peer-reviewed journals listed in Index Medicus/MEDLINE, the Cochrane Central Register of Controlled Clinical Trials, and the Cochrane Database of Systematic Reviews. Study selection . Randomized placebo-controlled clinical trials of at least 12 months' duration, in patients with a prior cardiovascular event or at high risk for cardiovascular events, were analyzed. Data synthesis and analysis. A total of 31 555 patients (136 882 patient-years) from 4 trials were selected for the meta-analysis. Relative risk estimations were made using data pooled from these trials, and statistical significance was determined using the χ2 test. The number of patients needed to treat was also calculated for each outcome. Results. Tissue ACE inhibitors significantly reduced the risk of all-cause mortality, cardiovascular mortality, acute myocardial infarction, and stroke ( P < .001 for each). The need for invasive coronary revascularization was reduced ( P = .03), as was the risk of hospitalization for congestive heart failure ( P = .001). The occurrence of new-onset diabetes was also significantly reduced ( P < .001), but the risk of hospitalization for angina was not significantly affected ( P = .677). Treating about 100 patients for about 4.5 years would prevent 1 death, 1 non-fatal myocardial infarction, 1 cardiovascular death, or 1 invasive coronary revascularization. Conclusions. Tissue ACE inhibitors have demonstrated benefit when used for secondary prevention of cardiovascular disease in patients with preserved left ventricular function in randomized placebo-controlled clinical trials.

Effect of foxtail millet protein hydrolysates on lowering blood pressure in spontaneously hypertensive rats

PURPOSE

The objective of this study was to determine the effect of foxtail millet protein hydrolysates on lowering blood pressure in spontaneously hypertensive rats (SHRs).

METHODS

The protein of foxtail millet after extruding or fermenting and the raw foxtail millet was extracted and hydrolyzed by digestive protease to generate angiotensin-converting enzyme (ACE) inhibitory peptides. The potential antihypertensive effect of protein hydrolysates from foxtail millet in SHRs was investigated.

RESULTS

After 4 weeks of treatment with 200 mg peptides/kg of body weight of protein hydrolysates, blood pressure was lowered significantly, and the raw and extruded samples were more effective than the fermented samples. The serum ACE activity and angiotensin II levels in the treatment groups were significantly lower than that of the control. The percent heart weight decreased in the treatment groups.

CONCLUSION

Thus, ingestion of foxtail millet protein hydrolysates especially for the raw and extruded hydrolysates may ameliorate hypertension and alleviate related cardiovascular diseases.

QM/MM investigation of the catalytic mechanism of angiotensin-converting enzyme

Angiotensin-converting enzyme (ACE) converts angiotensin I to angiotensin II and degrades bradykinin and other vasoactive peptides. ACE inhibitors are used to treat diseases such as hypertension and heart failure. It is thus highly desirable to understand the catalytic mechanism of ACE, as this should facilitate the design of more powerful and selective ACE inhibitors. ACE exhibits two different active domains, the C-domain and the N-domain. In this work, we systematically investigated the inhibitor- and substrate-binding patterns in the N-domain of human ACE using a combined quantum mechanical and molecular mechanical approach. The hydrolysis of hippuryl-histidyl-leucine (HHL) as catalyzed by the N-domain of human somatic ACE was explored, and the effects of chloride ion on the overall reaction were also investigated. Two models, one with and one without a chloride ion at the first binding position, were then designed to examine the chloride dependence of inhibitor-substrate binding and the catalytic mechanism. Our calculations indicate that the hydrolysis reaction follows a stepwise general base/general acid catalysis path. The estimated mean free energy barrier height in the two models is about 15.6 kcal/mol, which agrees very well with the experimentally estimated value of 15.8 kcal/mol. Our simulations thus suggest that the N-domain is in a mixed form during ACE-catalyzed hydrolysis, with the single-chloride-ion and the double-chloride-ion forms existing simultaneously. Graphical Abstract Superposition of ACE C- and N- domains.

Present and future pharmacotherapeutic agents in heart failure: an evolving paradigm

Many conditions culminate in heart failure (HF), a multi‐organ systemic syndrome with an intrinsically poor prognosis. Pharmacotherapeutic agents that correct neurohormonal dysregulation and haemodynamic instability have occupied the forefront of developments within the treatment of HF in the past. Indeed, multiple trials aimed to validate these agents in the 1980s and early 1990s, resulting in a large and robust evidence‐base supporting their use clinically. An established treatment paradigm now exists for the treatment of HF with reduced ejection fraction (HFrEF), but there have been very few notable developments in recent years. HF remains a significant health concern with an increasing incidence as the population ages. We may indeed be entering the surgical era for HF treatment, but these therapies remain expensive and inaccessible to many. Newer pharmacotherapeutic agents are slowly emerging, many targeting alternative therapeutic pathways, but with mixed results. Metabolic modulation and manipulation of the nitrate/nitrite/nitric oxide pathway have shown promise and could provide the answers to fill the therapeutic gap between medical interventions and surgery, but further definitive trials are warranted. We review the significant evidence base behind the current medical treatments for HFrEF, the physiology of metabolic impairment in HF, and discuss two promising novel agents, perhexiline and nitrite.

Host kinin B1 receptor plays a protective role against melanoma progression

Melanoma is a very aggressive tumor that arises from melanocytes. Late stage and widely spread diseases do not respond to standard therapeutic approaches. The kallikrein-kinin system (KKS) participates in biological processes such as vasodilatation, pain and inflammatory response. However, the role of KKS in tumor formation and progression is not completely understood. The role of the host kinin B1 receptor in melanoma development was evaluated using a syngeneic melanoma model. Primary tumors and metastasis were respectively induced by injecting B16F10 melanoma cells, which are derived from C57BL/6 mice, subcutaneously or in the tail vein in wild type C57BL/6 and B1 receptor knockout mice (B1^−/−). Tumors developed in B1^−/− mice presented unfavorable prognostic factors such as increased incidence of ulceration, higher levels of IL-10, higher activation of proliferative pathways such as ERK1/2 and Akt, and increased mitotic index. Furthermore, in the metastasis model, B1^−/− mice developed larger metastatic colonies in the lung and lower CD8⁺immune effector cells when compared with WT animals. Altogether, our results provide evidences that B1^−/− animals developed primary tumors with multiple features associated with poor prognosis and unfavorable metastatic onset, indicating that the B1 receptor may contribute to improve the host response against melanoma progression.

Preparation and Characterization of Cerium (III) Doped Captopril Nanoparticles and Study of their Photoluminescence Properties

In this research Ce3+ doped Captopril nanoparticles (Ce3+ doped CAP-NP) were prepared by a cold welding process and have been studied. Captopril may be applied in the treatment of hypertension and some types of congestive heart failure and for preventing kidney failure due to high blood pressure and diabetes. CAP-NP was synthesized by a cold welding process. The cerium nitrate was added at a ratio of 10% and the optical properties have been studied by photoluminescence (PL). The synthesized compounds were characterized by Fourier transform infrared spectroscopy. The size of CAP-NP was calculated by X-ray diffraction (XRD). The size of CAP-NP was in the range of 50 nm. Morphology of surface of synthesized nanoparticles was studied by scanning electron microscopy (SEM). Finally the luminescence properties of undoped and doped CAP-NP were compared. PL spectra from undoped CAP-NP show a strong pack in the range of 546 nm after doped cerium ion into the captopril appeared two bands at 680 and 357 nm, which is ascribed to the well-known 5d–4f emission band of the cerium.