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Introduction: The risk of thromboembolic events developing limits the dose of antiangiogenic agents, thereby reducing their efficacy. This retrospective study therefore sought to identify predictors for the development of antiangiogenic agent-induced thromboembolic events and to elucidate whether differences in the likelihood of thromboembolic events exist between different antiangiogenic agents or cancer types, to guide future strategies for optimizing safety, efficacy, and quality of life in patients receiving chemotherapy. Methods: This study retrospectively investigated 468 cancer patients who received chemotherapy with bevacizumab, ramucirumab, or aflibercept at our outpatient chemotherapy center between December 2016 and April 2022. Variables related to the development of thromboembolic events were extracted from the medical records, and multivariate logistic regression analysis was performed to identify predictors for the development of thromboembolic events. The Wilcoxon/Kruskal-Wallis test was used to detect significant differences between groups. Results: Significant factors included serum albumin level (odds ratio [OR] = 0.363, 95% confidence interval [CI] = 0.193–0.685; p = 0.0017) and diabetes mellitus (OR = 5.356, 95% CI = 1.711–16.769; p = 0.0039). Renin-angiotensin system inhibitors (OR = 0.307) had low OR, although it was not significant. No difference in the development of thromboembolic events was evident between cancer types (p = 0.0781), but differences were identified between the three antiangiogenic agents (p = 0.0132). Ramucirumab was associated with a lower likelihood of thromboembolic events. Conclusion: Serum albumin level and diabetes mellitus were identified as significant predictors for the development of antiangiogenic agent-induced thromboembolic events. In addition, the likelihood of thromboembolic events did not differ between cancer types but differed between antiangiogenic agents. Plain Language Summary: This retrospective study was designed to identify predictors for the development of antiangiogenic agent-induced thromboembolic events and to elucidate whether differences in the likelihood of thromboembolic events exist between different antiangiogenic agents or cancer types. This study investigated 468 cancer patients who received chemotherapy with bevacizumab, ramucirumab, or aflibercept at our outpatient chemotherapy center between December 2016 and April 2022. Variables related to the development of thromboembolic events were extracted from the medical records, and multivariate logistic regression analysis was performed to identify predictors for the development of thromboembolic events. The Wilcoxon/Kruskal-Wallis test was used to detect significant differences between groups. Significant factors included serum albumin level (odds ratio [OR] = 0.363, 95% confidence interval [CI] = 0.193–0.685) and diabetes mellitus (OR = 5.356, 95% CI = 1.711–16.769). Renin-angiotensin system inhibitors (OR = 0.307) had low OR, although it was not significant. No difference in the development of thromboembolic events was evident between cancer types (p = 0.0781), but differences were identified between the three antiangiogenic agents (p = 0.0132). Ramucirumab was associated with a lower likelihood of thromboembolic events. In conclusion, serum albumin level and diabetes mellitus were identified as significant predictors for the development of antiangiogenic agent-induced thromboembolic events. In addition, the likelihood of thromboembolic events did not differ between cancer types, but differed between antiangiogenic agents. [ABSTRACT FROM AUTHOR]

Blood pressure and fluid balance are regulated hormonally by renin-angiotensin system (RAS). Influence on this system could be achieved by different compounds that act as angiotensin-converting enzyme inhibitors (ACE inhibitors), angiotensin receptor blockers and renin inhibitors. The purpose of the present study is to predict the structures of the potent ACE inhibitors on the base of His-Leu peptide structural element of angiotensine I using computational methods. Different modifications were made in the structure of this dipeptide and the energy of binding with the enzyme were calculated. The docking results were analyzed and it was found that along with the important amino acid residue of the receptor molecule Arg167, the Tyr residues (35, 87, 88 and 92) as well as Cys180 are extremely important for the strong binding to the receptor and, accordingly, the manifestation of antagonistic action by the analogues. To block the receptor, the ligand molecule must have an intact terminal carboxyl group and an imidazole nucleus to participate in appropriate interactions. The inclusion of functional groups in the side chains of the amino acid residues of the dipeptide create an additional site for binding to the receptor. With the help of docking, the ligand molecule can be optimized, and this process is fast, saving the synthesis of many compounds and their biological testing. And finally, the most potent analogues will be synthesized and biologically tested. [ABSTRACT FROM AUTHOR]

Glioblastoma multiforme (GBM) is a highly aggressive and incurable disease accounting for about 10,000 deaths in the USA each year. Despite the current treatment approach which includes surgery with chemotherapy and radiation therapy, there remains a high prevalence of recurrence. Notable improvements have been observed in persons receiving concurrent antihypertensive drugs such as renin angiotensin inhibitors (RAS) or the antidiabetic drug metformin with standard therapy. Anti-tumoral effects of RAS inhibitors and metformin have been observed in in vitro and in vivo studies. Although clinical trials have shown mixed results, the potential for the use of RAS inhibitors and metformin as adjuvant GBM therapy remains promising. Nevertheless, evidence suggest that these drugs exert multimodal antitumor actions; by particularly targeting several cancer hallmarks. In this review, we highlight the results of clinical studies using multidrug cocktails containing RAS inhibitors and or metformin added to standard therapy for GBM. In addition, we highlight the possible molecular mechanisms by which these repurposed drugs with an excellent safety profile might elicit their anti-tumoral effects. RAS inhibition elicits anti-inflammatory, anti-angiogenic, and immune sensitivity effects in GBM. However, metformin promotes anti-migratory, anti-proliferative and pro-apoptotic effects mainly through the activation of AMP-activated protein kinase. Also, we discussed metformin's potential in targeting both GBM cells as well as GBM associated-stem cells. Finally, we summarize a few drug interactions that may cause an additive or antagonistic effect that may lead to adverse effects and influence treatment outcome. [ABSTRACT FROM AUTHOR]

We aimed to determine effects of aliskiren, a direct renin inhibitor, loaded onto polymeric nanoparticles on the (pro)renin receptor (Atp6ap2), angiotensin II type 1 receptor (Agtr1), and angiotensin-converting enzyme (ACE) gene expression in the heart of spontaneously hypertensive rats (SHR). Twelve-week-old male SHRs were divided into an untreated group and groups treated with powdered aliskiren or aliskiren-loaded nanoparticles (25 mg/kg/day). After three weeks, the accumulation of aliskiren, distribution of polymeric nanoparticles, gene expression of Atp6ap2 and Agtr1 receptors and ACE, and protein expression of NADPH oxidase along with the conjugated diene (CD) concentration were analyzed. The accumulation of aliskiren in the heart was higher in the aliskiren-loaded nanoparticle group than in the powdered group. The fluorescent signals of nanoparticles were visible in cardiomyocytes, vessel walls, and erythrocytes. Aliskiren-loaded nanoparticles decreased the gene expression of Atp6ap2 and ACE, while not affecting Agtr1. Both forms of aliskiren decreased the protein expression of NADPH oxidase, with a more pronounced effect observed in the aliskiren-loaded nanoparticle group. CD concentration was decreased only in the aliskiren-loaded nanoparticle group. We hypothesize that aliskiren-loaded nanoparticle-mediated downregulation of Atp6ap2 and ACE may contribute to a decrease in ROS generation with beneficial effects in the heart. Moreover, polymeric nanoparticles may represent a promising tool for targeted delivery of aliskiren. [ABSTRACT FROM AUTHOR]

Background: Diabetic kidney disease (DKD) is a health burden of rising importance. Slowing progression to end stage kidney disease is the main goal of drug treatment. The aim of this analysis is to compare drug treatments of DKD by means of a systemic review and a network meta-analysis. Methods: We searched Medline, CENTRAL and clinicaltrials.gov for randomized, controlled studies including adults with DKD treated with the following drugs of interest: single angiotensin-converting-enzyme-inhibitor or angiotensin-receptor-blocker (single ACEi/ARB), angiotensin-converting-enzyme-inhibitor and angiotensin-receptor-blocker combination (ACEi+ARB combination), aldosterone antagonists, direct renin inhibitors, non-steroidal mineralocorticoid-receptor-antagonists (nsMRA) and sodium-glucose cotransporter-2 inhibitors (SGLT2i). As primary endpoints, we defined: overall mortality and end-stage kidney disease, as secondary endpoints: renal composite outcome and albuminuria and as safety endpoints: acute kidney injury, hyperkalemia and hypotension. Under the use of a random effects model, we computed the overall effect estimates using the statistic program R4.1 and the corresponding package "netmeta". Risk of bias was assessed using the RoB 2 tool and the quality of evidence of each pairwise comparison was rated according to GRADE (Grading of Recommendations Assessment, Development and Evaluation). Results: Of initial 3489 publications, 38 clinical trials were found eligible, in total including 42346 patients. Concerning the primary endpoints overall mortality and end stage kidney disease, SGLT2i on top of single ACEi/ARB compared to single ACEi/ARB was the only intervention significantly reducing the odds of mortality (OR 0.81, 95%CI 0.70–0.95) and end-stage kidney disease (OR 0.69, 95%CI 0.54–0.88). The indirect comparison of nsMRA vs SGLT2i in our composite endpoint suggests a superiority of SGLT2i (OR 0.60, 95%CI 0.47–0.76). Concerning safety endpoints, nsMRA and SGLT2i showed benefits compared to the others. Conclusions: As the only drug class, SGLT2i showed in our analysis beneficial effects on top of ACEi/ARB treatment regarding mortality and end stage kidney disease and by that reconfirmed its position as treatment option for diabetic kidney disease. nsMRA reduced the odds for a combined renal endpoint and did not raise any safety concerns, justifying its application. [ABSTRACT FROM AUTHOR]

Hypertension is frequent in children with chronic kidney disease (CKD). Its prevalence varies according to CKD stage and cause. It is relatively uncommon in children with congenital kidney disease, while acquired kidney disease is associated with a higher prevalence of hypertension. Studies in children with CKD utilizing ambulatory blood pressure monitoring also showed a high prevalence of masked hypertension. Uncontrolled and longstanding hypertension in children is associated with progression of CKD. Aggressive treatment of high blood pressure should be an essential part of care to delay CKD progression in children. [ABSTRACT FROM AUTHOR]

Background and Objectives Dual renin-angiotensin-aldosterone system (RAAS) blockade involves dual therapy with a combination of angiotensin-converting enzyme inhibitors (ACEis), angiotensin-receptor blockers (ARBs), direct renin inhibitors (DRIs), or mineralocorticoid receptor antagonists (MRAs). It is hypothesized that dual RAAS blockade would result in a more complete inhibition of the RAAS cascade. However, large clinical trials on dual RAAS inhibition have shown increased risk of acute kidney injury (AKI) and hyperkalemia without additional benefit on mortality, cardiovascular events, or chronic kidney disease (CKD) progression compared to RAAS inhibitor monotherapy in patients with diabetic kidney disease (DKD). The development of newer, more selective non-steroidal MRAs as cardiorenal protective therapies has created a new opportunity for dual RAAS inhibition. We conducted a systematic review and meta-analysis of the risks of AKI and hyperkalemia with dual RAAS blockade in patients with DKD. Design, setting, participants, and measurements This is a systematic review and meta-analysis of the randomized controlled trials (RCT) published from 1 January 2006 to 30 May 2022. The study population included adult patients with DKD receiving dual RAAS blockade. A total of 31 RCTs and 33   048 patients were included in the systematic review. Pooled risk ratios (RRs) and 95% confidence intervals (CIs) were calculated using random effects. Results There were 208 AKI events in 2690 patients on ACEi + ARB versus 170 in 4264 patients with ACEi or ARB monotherapy (pooled RR 1.48, 95% CI: 1.23–1.39). There were 304 hyperkalemia events in 2818 patients on ACEi + ARB versus 208 in 4396 patients with ACEi or ARB monotherapy (pooled RR 1.97, 95% CI: 1.32–2.94). A non-steroidal MRA + ACEi or ARB showed no increase in the risk of AKI (pooled RR 0.97, 95% CI: 0.81–1.16) compared to ACEi or ARB monotherapy but had a 2-fold higher risk of hyperkalemia with 953 events in 7837 patients in dual therapy versus 454 events in 6895 patients in monotherapy (pooled RR 2.05, 95% CI: 1.84–2.28). A steroidal MRA + ACEi or ARB had a 5-fold higher risk of hyperkalemia with 28 events in 245 at risk in dual therapy versus five events in 248 at risk in monotherapy (pooled RR 5.42 95% CI: 2.15–13.67). Conclusion Dual therapy with RAASi is associated with an increased risk of AKI and hyperkalemia compared to RAASi monotherapy. Conversely, dual therapy with RAAS inhibitors and non-steroidal MRAs have no additional risk of AKI but a similar risk of hyperkalemia, which is lower than dual therapy with RAAS inhibitors and steroidal MRAs. [ABSTRACT FROM AUTHOR]

The Renin–Angiotensin System (RAS) has attracted considerable interest beyond its traditional cardiovascular role due to emerging data indicating its potential involvement in neurodegenerative diseases, including Alzheimer's dementia (AD). This review investigates the therapeutic implications of RAS modulators, specifically focusing on angiotensin-converting enzyme inhibitors (ACEIs), angiotensin receptor blockers (ARBs), and renin inhibitors in AD. ACEIs, commonly used for hypertension, show promise in AD by reducing angiotensin (Ang) II levels. This reduction is significant as Ang II contributes to neuroinflammation, oxidative stress, and β-amyloid (Aβ) accumulation, all implicated in AD pathogenesis. ARBs, known for vasodilation, exhibit neuroprotection by blocking Ang II receptors, improving cerebral blood flow and cognitive decline in AD models. Renin inhibitors offer a novel approach by targeting the initial RAS step, displaying anti-inflammatory and antioxidant effects that mitigate AD degeneration. Preclinical studies demonstrate RAS regulation's favorable impact on neuroinflammation, neuronal damage, cognitive function, and Aβ metabolism. Clinical trials on RAS modulators in AD are limited, but with promising results, ARBs being more effective that ACEIs in reducing cognitive decline. The varied roles of ACEIs, ARBs, and renin inhibitors in RAS modulation present a promising avenue for AD therapeutic intervention, requiring further research to potentially transform AD treatment strategies. [ABSTRACT FROM AUTHOR]

This review considers the chiral phosphorus-containing drugs used to treat patients in the clinic, as well as the promising and experimental drugs that are in the process of being researched. Natural and synthetic representatives of phosphorus-containing drugs, such as tenofovir (hepatitis B and HIV treatment), fosfomycin (antibiotic), valinofos (antibiotic), phosphazinomycin A (antibiotic), (R)-phospholeucine, various antibacterial and antifungal agents, renin inhibitors, etc., have found practical applications as medicines and bioregulators and other medicines. The influence of the chirality of both carbon atoms and phosphorus atoms on the pharmacodynamics, pharmacokinetics, and toxicological properties of phosphorus drugs has been demonstrated. Therefore, the choice of enantiomers is critical since the wrong choice of a chiral drug can lead to undesirable consequences, carcinogenicity, and teratogenicity. New chiral technologies affecting drug development are discussed, such as the "chiral switch" of racemates already on the market, as well as phosphorus-containing prodrugs with a higher biological selectivity and low adverse effects. [ABSTRACT FROM AUTHOR]

Renin inhibitors derived from natural ingredients often belong to the saponin or polyphenol chemical class. Pegagan (Centella asiatica) is a natural plant in Indonesia that contains saponins and polyphenols. The active compounds of Pegagan include asiaticoside, madasiatic acid, madecassoside, madecassic acid, and asiatic acid. This study investigates the possible renin-inhibitory properties of phytochemicals from Centella asiatica using in-silico molecular docking. Using AutoDock v4.2.6, up to five C. asiatica compounds were docked with 2V0Z Renin with Inhibitor 10 (Aliskiren) in human subjects (Homo sapiens 6LU7). These compounds included asiaticoside, madasiatic acid, madecassoside, madecassid acid, and asiatic acid. SwissADME was used to evaluate these drugs' pharmacokinetic characteristics. The molecular docking results of 5 test ligands obtained affinity energy values from -8.7 kcal/mol to -10.4 kcal/mol. In contrast, the affinity energy value for the comparison ligand (aliskiren) is -9.0 kcal/mol. Madecasosside has an affinity energy value of -10.4 kcal/mol, asiaticoside of -9.6 kcal/mol and asiatic acid of -9.2 kcal/mol. Based on this energy affinity value, the active compound C. asiatica has the potential as a renin inhibitor. Pharmacokinetic analysis revealed that asiatic acid, madecassic acid, madasiatic acid, and asiatic acid have good pharmacokinetic properties. It may be concluded based on in silico molecular docking and pharmacokinetics investigation that the molecule most strongly suggested for additional in vitro renin inhibitor research was asiatic acid. Keywords: Renin Inhibitor, Centella asiatica, Molecular Docking. [ABSTRACT FROM AUTHOR]

Aliskiren is referred to as a direct renin inhibitor. renin catalysis the conversion of angiotensinogen to angiotensin-1 Aliskiren and Valsartan use as hypertension. Valsartan belongs to the angiotensin 2 receptor blocker family. Which prevent the protein angiotensin 2. Cardiac stimulation and renal reabsorption of sodium. This review article represents the collection and discussion of various analytical methods available in the literature for the determination of Aliskiren and Valsartan in pharmaceutical and biological samples consisting of UV spectroscopy, RP-HPLC, HPTLC, LCMS/MS methods. The anticipated review provides details about the comparative utilization of various analytical techniques for the determination of Aliskiren and Valsartan alone and in combination. The present review article can be effectively explored to conduct future analytical investigation for the estimation of Aliskiren and Valsartan. [ABSTRACT FROM AUTHOR]

Flavonoids have various pharmacological activities, such as antihypertensive, anticancer, and and antidiabetic effects. Several studies have shown that luteolin, quercetin, kaempferol, myricetin, naringenin, hesperetin, and epicatechin have antihypertensive effects, but the mechanism of action has yet to be discovered with certainty. This study aims to identify flavonoids from luteolin, quercetin, kaempferol, myricetin, naringenin, hesperetin, and epicatechin as renin inhibitors through in silico study; seven flavonoid compounds were docked with 2V0Z with renin inhibitor (Aliskiren) in humans (Homo sapiens 6 LU7) using AutoDock v4.2.6. SwissADME was used to evaluate the pharmacokinetic characteristics of these substances. Results molecular binding of luteolin, quercetin, kaempferol, myricetin, naringenin, hesperetin, and epicatechin, has potential as renin inhibitors with affinity energy values lower than those of aliskiren of -9.3; -9.3; -10.0; -9.2; -9.9; -9.3; and -9.7 kcal/mol. The interactions of these seven compounds have the same catalytic activity as aliskiren on two aspartic acid residues, Asp32 and Asp215. The analysis of pharmacokinetic profiles and the search for physical and chemical properties showed that the seven compounds violated three of the five Lipinski rules, while aliskiren violated one. Hesperitin, kaempferol, and naringenin had similarities with aliskiren on the amino-acid residues in the renin-binding pocket. However, based on pharmacokinetic analysis, the three compounds had an oral pharmacokinetic profile that could have been better than aliskiren. [ABSTRACT FROM AUTHOR]

Genetic variants in the third intron of the PRDM6 gene have been associated with BP traits in multiple GWAS. By combining fine mapping, massively parallel reporter assays, and gene editing, we identified super enhancers that drive the expression of PRDM6 and are partly regulated by STAT1 as the causal variants for hypertension. The heterozygous disruption of Prdm6 in mice expressing Cre recombinase under the control of mouse smooth muscle cell protein 22-a promoter (Prdm6fl/+ SM22- Cre) exhibited a markedly higher number of renin-producing cells in the kidneys at E18.5 compared with WT littermates and developed salt-induced systemic hypertension that was completely responsive to the renin inhibitor aliskiren. Strikingly, RNA-Seq analysis of the mouse aortas identified a network of PRDM6-regulated genes that are located in GWAS-associated loci for blood pressure, most notably Sox6, which modulates renin expression in the kidney. Accordingly, the smooth muscle cell-specific disruption of Sox6 in Prdm6fl/+ SM22-Cre mice resulted in a dramatic reduction of renin. Fate mapping and histological studies also showed increased numbers of neural crest-derived cells accompanied by increased collagen deposition in the kidneys of Prdm6fl/+ Wnt1Cre-ZsGreen1Cre mice compared with WT mice. These findings establish the role of PRDM6 as a regulator of renin-producing cell differentiation into smooth muscle cells and as an attractive target for the development of antihypertensive drugs. [ABSTRACT FROM AUTHOR]

The construction of functionalized cyclopropanes is a hot topic in synthetic chemistry as they are important 3C starting materials and privileged structures in medicinal chemistry. By treating the readily available cyclopropenes with sulfonyl iodides in water, β-iodo cyclopropyl sulfones were diastereoselectively formed via a syn-addition process in high yields. Employment of water as the sole solvent, avoidance of transition metals and air-sensitive reagents, and chromatography-free purification of the products make this transformation quite operationally convenient and environmentally benign. This method could be extended to various styrenes and alkynes, and the reactions with alkynes exhibited excellent anti-addition selectivity. It should be noted that post-modification of several natural products and drugs has been achieved, and this transformation has been successfully applied as a key step in the synthesis of a quinolinone MAT2A inhibitor and in the formal synthesis of a dipeptide renin inhibitor. [ABSTRACT FROM AUTHOR]

Introduction: Renin-angiotensin system inhibitors have been reported to exert protective effects against organ damage and failure; however, the impact of the direct renin inhibitor as monotherapy has not been assessed. Here, we investigated the effects of 24-week monotherapy with aliskiren compared to amlodipine in hypertensive patients with type 2 diabetes or obesity. Methods: In this randomized intervention study, 62 adult hypertensive patients with visceral obesity (defined as a body mass index [BMI] greater than 25 kg/m2 and a visceral adipose tissue area [VFA] greater than 100 cm2) or type 2 diabetes mellitus (age 57 ± 13, 65% men, BMI 28.8 ± 4.8 kg/m2, VFA 134.8 ± 47.0 cm2, blood pressure 141 ± 16/86 ± 13 mm Hg) were randomized to receive 24-week treatment with aliskiren (max. 300 mg) or amlodipine (max. 10 mg). The primary outcome was the change in VFA at 24 weeks post-treatment. Results: Change in VFA did not differ significantly from baseline in either group. Systolic blood pressure significantly decreased at 12 weeks (−10 mm Hg, p = 0.001) and 24 weeks (−10 mm Hg, p = 0.001) in the amlodipine group and at 24 weeks (−11 mm Hg, p = 0.001) in the aliskiren group. Diastolic blood pressure significantly decreased at 24 weeks (−6 mm Hg, p = 0.009) only in the amlodipine group. Although the estimated glomerular filtration rates did not significantly change in either group, the logarithm of urinary albumin excretion significantly decreased at 24 weeks only in the aliskiren group (−0.60, p < 0.001). The 24-week changes in the urinary albumin excretion significantly correlated with the changes in the plasma renin activity in the aliskiren group (r = 0.51, p = 0.008). Conclusion: Aliskiren monotherapy did not show any superiority to amlodipine monotherapy on VFA, estimated glomerular filtration rates, or urinary albumin excretion in obese or type 2 diabetic hypertensive patients. [ABSTRACT FROM AUTHOR]

Hypertension is a silent killer that causes kidney, heart, and stroke damage if not handled properly. In Indonesia, the prevalence of the population with high blood pressure is 34.11% with women 36.85% higher than men 31.34%, this shows a fairly high value so that special attention is needed on hypertension therapy. It is known that currently there are 6 types of pharmacological therapy for hypertension and one of the newest is the renin inhibitor class (Aliskiren). Indonesia has diverse natural wealth in the form of flora and fauna, with a wealth of more than 30,000 types of medicinal plants with 9500 potential herbal medicines that have not been utilized optimally, with the largest exporter of herbal medicines in the world. Centella asiatica plants containing triterpenoid saponins have high renin inhibitor activity, namely the content of Asiaticoside and Madecasoside. The research method was carried out in silico using molecular simulation and in vitro with fluorometry (328/552 nm) to test the activity of asiaticoside and madecasoside compounds as well as a mixture of asiaticoside and madecasoside in Centella asiatica plants. This is supported by the docking outcome. The docking results show that madecososide compounds have a gibbs energy close to the positive control aleskiren (-8.356 kcal/mol) and aleskiren (-9.44 kcal/mol). The experiment results showed that the triterpenoid saponin compound (madecassoside) contained an IC value of 0.71, at a concentration of 5 µg/µl, and absorbance of 1.35 A in the first minute. The strongest renin inhibition was Madecasoside compound with a concentration of 5 µg/µl with an average value of fluorescent adsorption and an average percent inhibition of 135% with the best renin inhibition at Madecasoside 5 ug/ul the first minute with absorbance values 1.19 A. Finally, the in silico result corresponded to the in vitro experiment. Centella asiatica plants have renin inhibitor activity as antihypertensive, especially in secondary metabolites of triterpene saponins with pure madecasoside compounds compared with aliskiren as a renin inhibitor. So that the compound madecasoside has renin inhibitor activity as an antihypertensive. [ABSTRACT FROM AUTHOR]

The natriuretic peptide system (NPS) is the key driving force of the heart's endocrine function. Recent developments in NPS-targeted therapies have been found promising and effective against cardiovascular diseases, including hypertension. Notably, after discovering crosstalk between NPS and the renin-angiotensin-aldosterone system (RAAS), various combinations such as neprilysin/angiotensin II receptor type 1 AT 1 receptor inhibitors and neprilysin/renin inhibitors have been preclinically and clinically tested against various cardiac complications. However, the therapeutic effects of such combinations on the pathophysiology of hypertension are poorly understood. Furthermore, the complicated phenomena underlying NPS regulation and function, particularly in hypertension, are still unexplored. Mounting evidence suggests that numerous regulatory mechanisms modulate the expression of NPS, which can be used as potential targets against hypertension and other cardiovascular diseases. Therefore, this review will specifically focus on epigenetic and other regulators of NPS, identifying prospective regulators that might serve as new therapeutic targets for hypertension. More importantly, it will shed light on recent developments in NPS-targeted therapies, such as M-atrial peptides, and their latest combinations with RAAS modulators, such as S086 and sacubitril-aliskiren. These insights will aid in the development of effective therapies to break the vicious cycle of high blood pressure during hypertension, ultimately addressing the expanding global heart failure pandemic. [ABSTRACT FROM AUTHOR]

• Acute kidney injury (AKI) during the aging process is particularly of significant concern. • Increased AKI risk is linked to using multiple NSAIDs, the parenteral dosage form, and higher cumulative doses. • Dual combination of RAS blockade with NSAIDs or diuretics with NSAIDs, as well as triple therapy, heightens the AKI risk. Aging-related physiological changes, such as decline in renal function, not only exacerbates pre-existing comorbidities but also escalate the susceptibility to adverse events. Previous studies have shown that non-steroidal anti-inflammatory drugs (NSAIDs) are associated with an increased risk of acute kidney injury (AKI), and the concomitant use of renin-angiotensin system blockade or diuretics may further potentiate the risk. However, studies evaluating the risk of AKI associated with NSAIDs (including routes, concomitant use of different NSAIDs, categories (traditional NSAIDs or COX-2 inhibitors), and cumulative doses of NSAIDs) are limited, particularly the risk of AKI associated with the dual or triple combination of NSAIDs with renin-angiotensin system blockade (RAS blockades) and/or diuretics. A case-crossover study utilized two sets of longitudinal data from Taiwan's National Health Insurance Research Database (NHIRD). Newly admitted patients with a primary AKI diagnosis were included, with the index date defined as the first admission date. The 1–7 days and 181–187 days prior to the index date served as the case and control periods. Exposure to NSAIDs and co-exposures of RAS blockade and/or diuretics were assessed in both periods. Multivariable conditional logistic regression models, adjusting for potential confounders, estimated adjusted odds ratios (aORs) and 95 % confidence intervals (CIs) for AKI associated with NSAIDs, dual, or triple combinations. Sensitivity analyses explored result robustness by varying case and control period lengths. The study included 1,284 newly diagnosed AKI patients. NSAIDs showed a 3.55-fold increased risk of AKI (aOR: 3.55; 95 % CI 2.70–4.65), with similar risks for traditional NSAIDs and COX-2 inhibitors. Use of multiple NSAIDs, parenteral dosage forms, and higher cumulative doses increased AKI risk. Dual combination with either RAS blockade or diuretics resulted in a 2.90-fold (aOR: 2.90; 95 %CI 1.47–5.70) and 12.68-fold (aOR: 12.68; 95 %CI 6.15–26.12) risk, respectively. The highest risk occurred with triple combination (aOR: 29.22; 95 %CI 12.82–66.64). NSAIDs, including both non-selective NSAIDs and COX2 inhibitors, elevate the risk of AKI. Increased AKI risk is linked to using multiple NSAIDs, the parenteral dosage form, and higher cumulative doses. Dual combination of RAS blockade with NSAIDs or diuretics with NSAIDs, as well as triple therapy, heightens the risk, with the latter associated with the highest risk of AKI. [ABSTRACT FROM AUTHOR]

Depression is considered a neuropsychic disease that has global prevalence and is associated with disability. The pathophysiology of depression is not well understood; however, emerging evidence has indicated that neuroinflammation could contribute to developing depression symptoms. One of the factors that have a role in the development of neuroinflammation is the renin–angiotensin system. Therefore, the goal of the current study is to determine the antidepressant-like effects of Aliskiren, a renin inhibitor, against lipopolysaccharide (LPS)-induced depressive-like behavior in mice, glial cell activation, and the upregulation of proinflammatory cytokines in the prefrontal cortex. For behavioral studies, the open field test (OFT), tail suspension test (TST), forced swim test (FST), and sucrose preference test (SPT) were used. Inflammatory markers were assessed using real-time polymerase chain reaction (RT-PCR). LPS administration (0.5 mg/kg, intraperitoneal injection (i.p.)) sufficiently reduced the number of crossings in OFT, whereas Aliskiren pretreatment (10 mg/kg, i.p.) attenuated the LPS effect for two hours after LPS injection. The treatments did not show effects on locomotor activity in OFT 24 h after LPS administration. LPS increased the immobility time in TST and FST or reduced sucrose consumption in SPT after 24 h. Aliskiren reversed the effects induced by LPS in TST, FST, and SPT. CD11 b mRNA, a microglial marker, GFAP mRNA, an astroglial marker, and proinflammatory cytokines genes (TNF-α, IL-1β, and IL-6) were upregulated in the prefrontal cortex in LPS exposed animals. However, Aliskiren reduced LPS-induced inflammatory genes in the prefrontal cortex. Hence, the outcomes conclude that Aliskiren prevents depressive illness associated with neuroinflammation in humans. [ABSTRACT FROM AUTHOR]

The renin--angiotensin--aldosterone system (RAAS) cascade has a significant effect on several systems. Angiotensin II (AngII) has appeared as not only a vasoactive peptide but also as a multifunctional cytokine that displays several non-hemodynamic properties beyond renal hemodynamic properties. The kidney includes total components of the RAAS such as aldosterone and AngII not only adjust renal hemodynamics and reabsorption of sodium but also activating various inflammatory and fibrotic responses. Inhibition of the RAAS is one of the most potent methods to impede the development of renal diseases such as chronic kidney disease (CKD) and its related problems such as high blood pressure and heart disorders. Aliskiren, an octanamide, nonpeptide piperidine, orally, active, first commercially available, and direct renin inhibitor (DRI), impedes RAAS and operates by attaching to the active sites of renin and may be effective for the management of renal disease because of blocking the RAAS at its point of start and most sensitive step. Based on numerous studies, aliskiren is the greatest powerful inhibitor of AngII extents among RAAS inhibitors, even though it is unable to prevent the (pro) renin receptor-mediated extracellular signal-regulated kinase 1 and 2 (ERK1/2) activations. In this review, it is described renoprotective effects of aliskiren against different types of nephropathy such as acute kidney injury, diabetic nephropathy, and hypertensive nephropathy. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic has urged for the repurposing of existing drugs for rapid management and treatment. Renin inhibitors down regulation of ACE2, which is an essential receptor for SARS-CoV-2 infection that is responsible for COVID-19, in addition to their ability to act as protease inhibitors were encouraging aspects for their investigation as possible inhibitors of main protease of SARS-CoV-2 via computational studies. A Pharmacophore model was generated using the newly released SARS-COV-2 main protease inhibitors. Virtual screening was performed on renin inhibitors, and Drug likeness filter identified remikiren and 0IU as hits. Molecular docking for both compounds showed that the orally active renin inhibitor remikiren (Ro 42–5892) of Hoffmann–La Roche exhibited good molecular interaction with Cys145 and His41 in the catalytic site of SARS-CoV-2 main protease. Molecular dynamics simulation suggested that the drug is stable in the active site of the enzyme. Image 1 • For rapid management of COVID-19, drug repurposing was widely carried out. • Renin inhibitors downregulate ACE2, decreasing the risk of SARS-COV-2 infection. • SARS-COV-2 main protease is a potential target for renin inhibitors. • Pharmacophore model was generated and virtually screened on renin inhibitors. • Remikiren was a hit, furtherly studied through molecular docking and dynamics. [ABSTRACT FROM AUTHOR]

1. The pharmacokinetics of TAK-272 (SCO-272), an orally active renin inhibitor, was investigated in rats with subcutaneously injected turpentine oil, which was an inflammation animal model. 2. Following intravenous administration of TAK-272 to the turpentine-treated rats, the systemic clearance and volume of distribution decreased with the elevated plasma a1-acid glycoprotein (AGP) levels. The elevated plasma AGP levels were negatively correlated with the plasma unbound fraction of TAK-272 in the rats. Although the AUCs of total TAK-272 in the turpentine-treated rats were higher than those in the control rats after intravenous and oral administration, those of unbound TAK-272, which seem to directly contribute to the pharmacological effect and safety, were nearly equal between the turpentine-treated and control rats in the respective dose routes. TAK-272 has been shown to primarily bind to AGP in the human plasma. 3. These results strongly suggested that the pharmacokinetic of TAK-272 in humans would also be affected by the variation in the plasma AGP levels and should be discussed with not only the total concentrations but also the unbound concentrations in the clinical trial for patients with elevated plasma AGP levels. [ABSTRACT FROM AUTHOR]

It has been demonstrated that certain angiotensin‐converting enzyme (ACE) inhibitors and angiotensin AT1 receptor antagonists can possess anticonvulsant activity. The purpose of the current study was to examine the effect of aliskiren, a direct renin inhibitor and a novel antihypertensive drug, against pentylenetetrazole (PTZ)‐induced clonic seizures in mice and on the protective activity of conventional antiepileptic drugs (AEDs) in this seizure model. Effects of aliskiren on the PTZ threshold and the protective efficacy of AEDs, such as clonazepam (CLO), phenobarbital (PB), valproate (VPA), and ethosuximide (ETX) in the PTZ test, were evaluated in adult Swiss mice. Aliskiren and AEDs were administered intraperitoneally (i.p.) while PTZ (50–100 mg/kg) was injected subcutaneously (s.c.). The rota‐rod and passive avoidance test were used to assess the adverse effects of the combined treatment with aliskiren and AEDs. Aliskiren, at the dose of 75 mg/kg, significantly raised the PTZ threshold (P < 0.05). Furthermore, aliskiren, at the subthreshold dose of 50 mg/kg, significantly enhanced the protective action of CLO (P < 0.01), PB (P < 0.01), and VPA (P < 0.05) but not ETX (P > 0.05) in the s.c. PTZ test. Motor coordination in the rota‐rod test and long‐term memory in the passive avoidance task were not impaired by the combined treatment of the drugs. This study suggests that treatment with aliskiren can be useful in hypertensive patients with myoclonic seizures. Certainly, a clinical verification of using aliskiren in such patients would be necessary. [ABSTRACT FROM AUTHOR]

Imarikiren hydrochloride (TAK‐272/SCO‐272) is a novel direct renin inhibitor with potential indications for cardiovascular and renal diseases. This phase I study evaluated the pharmacokinetics, pharmacodynamics and safety of a single oral administration of imarikiren in healthy Japanese male subjects. The Dose‐Ascending part (double‐blind, placebo‐controlled, parallel‐group design; n = 60) comprised six steps from 5 to 200 mg (n = 8 for imarikiren and n = 2 for placebo per step). The Food Effect part (n = 12) was an open‐label, 2 × 2 crossover design with a dose of 50 mg to evaluate the effect of food on the pharmacokinetics and safety of imarikiren. There was a generally linear relationship between dose and area under the plasma concentration–time curve (0 to infinity) or maximum plasma concentration of imarikiren. Food had no clinically significant effect on the exposure of imarikiren. Inhibition of plasma renin activity was rapid and lasted up to 24 hr at all doses. Plasma active renin concentration increased, reaching a maximum at approximately 6 hr, in a nearly dose‐dependent manner. Across both study parts, the number of subjects with treatment‐emergent adverse events ranged from 0 to 3 per group with no dependency on dose. All treatment‐emergent adverse events except two were mild in intensity; there were no serious adverse events or deaths. Single oral administration of imarikiren from 5 to 200 mg was safe and well tolerated. These findings suggest that further clinical development of a once‐daily imarikiren regimen is warranted. [ABSTRACT FROM AUTHOR]

Legumes are rich sources of protein in human diet and their consumption has been associated with the prevention of chronic diseases attributable to their bioactive components. Pigeon pea (Cajanus cajan) is an underutilized legume with relatively high protein content (~24%). Protein hydrolysates were prepared from pea isolate by enzymatic hydrolysis using pepsin and pancreatin. Hydrolysates were evaluated for their amino acid composition, antioxidant properties, in vitro and in vivo antihypertensive properties. The hydrolysates had high hydrophobic amino acids, especially isoleucine, phenylalanine, and leucine. Pepsin‐pancreatin‐hydrolyzed pea protein (PPHPp) showed significantly higher ability to scavenge DPPH˙ while pancreatin‐hydrolyzed pea protein (PPHPa) had higher ˙OH, ABTS˙+ scavenging, Fe3+ reducing and linoleic acid peroxidation inhibition. PPHPp exhibited superior angiotensin‐converting enzyme inhibition (61.82%) while PPHPa showed higher renin inhibition (14.28%). PPHPp exhibited strong antihypertensive effect, showing an instantaneous systolic blood pressure lowering effect (−26.12 mmHg) within 2‐h post‐oral administration. Pigeon pea protein hydrolysate (especially from pancreatin digest) could therefore, be a promising source of bioactive peptides and potential ingredient for formulation of functional foods against oxidative stress and hypertension. Bioactive peptides were obtained from pigeon pea isolate via enzymatic hydrolysis. Pigeon pea peptides showed good inhibitory activity against ACE and renin. Hydrolysates exhibited systolic blood pressure reduction in hypertensive rats. [ABSTRACT FROM AUTHOR]

The renin-angiotensin system (RAS), which plays an important role in the progression of heart failure, is efficiently blocked by the inhibition of renin, the rate-limiting enzyme in the RAS cascade. In the present study, we investigated the cardioprotective effects of TAK-272 (SCO-272, imarikiren), a novel, orally effective direct renin inhibitor (DRI), and compared its efficacy with that of aliskiren, a DRI that is already available in the market. TAK-272 was administered to calsequestrin transgenic (CSQ-tg) heart failure mouse model that show severe symptoms and high mortality. The CSQ-tg mice treated with 300 mg/kg, the highest dose tested, of TAK-272 showed significantly reduced plasma renin activity (PRA), cardiac hypertrophy, and lung congestion. Further, TAK-272 reduced cardiomyocyte injury accompanied by an attenuation of the increase in NADPH oxidase 4 and nitric oxide synthase 3 expressions. TAK-272 also prolonged the survival of CSQ-tg mice in a dose-dependent manner (30 mg/kg: P = 0.42, 100 mg/kg: P = 0.12, 300 mg/kg: P < 0.01). Additionally, when compared at the same dose level (300 mg/kg), TAK-272 showed strong and sustained PRA inhibition and reduced the heart weight and plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) concentration, a heart failure biomarker, while aliskiren showed a significant weaker PRA inhibition and failed to demonstrate any cardioprotective effects. Our results showed that TAK-272 is an orally active and persistent renin inhibitor, which reduced the mortality of CSQ-tg mice and conferred protection against cardiac hypertrophy and injury. Thus, TAK-272 treatment could provide a new therapeutic approach for heart failure. [ABSTRACT FROM AUTHOR]

We previously identified 2- tert -butyl-4-[(3-methoxypropyl)amino]- N -(2-methylpropyl)- N -[(3 S ,5 R )-5-(morpholin-4-ylcarbonyl)piperidin-3-yl]pyrimidine-5-carboxamide 3 as a potent renin inhibitor. Since 3 showed unacceptably low bioavailability (BA) in rats, structural modification, using SBDD and focused on physicochemical properties was conducted to improve its PK profile while maintaining renin inhibitory activity. Conversion of the amino group attached at the 4-position of pyrimidine to methylene group improved PK profile and decreased renin inhibitory activity. New central cores with carbon side chains were explored to improve potency. We had designed a series of 5-membered azoles and fused heterocycles that interacted with the lipophilic S3 pocket. In the course of modification, renin inhibitory activity was enhanced by the formation of an additional hydrogen bonding with the hydroxyl group of Thr77. Consequently, a series of novel benzimidazole derivatives were discovered as potent and orally bioavailable renin inhibitors. Among those, compound 13 exhibited more than five-fold of plasma renin inhibition than aliskiren in cynomolgus monkeys at dose ratio. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the effects of Aliskerin on functional pancreatic β cell mass in type 2 diabetic mice. Study Design: Analytical experimental study. Place and Duration of Study: The study was conducted at the animal house of National Institute of Health, Islamabad. Duration of the study was of twelve weeks after initial acclimatization of one week. Material and Methods: Twenty four BALB/c mice, both male and female, of 35 to 40 grams were used for this study. Animals were randomly divided into four groups. Two served as control, one was normal and the other was diabetic control. The remaining two were used as interventional groups and received either pioglitazone or aliskerin for four weeks after induction of diabetes. Fasting blood glucose levels with fasting insulin levels were estimated. Insulin resistance was determined by calculating homa IR and pancreatic morphology was assessed by evaluating pancreatic beta cell mass. Results: After treatment, pioglitazone reduced all the biochemical parameters significantly when compared with diabetic control and negative correlation between glucose and insulin was changed into positive correlation (r value, 0.92) with significant p-value (0.015), while aliskerin caused a significant rise (p-value 0.009) in functional pancreatic β cell mass. Conclusion: Aliskerin has a significant anti-diabetic role as far as pancreatic morphology is concerned. [ABSTRACT FROM AUTHOR]

Experimental studies showed that certain angiotensin-converting enzyme inhibitors and angiotensin AT 1 receptor antagonists can decrease seizure severity in rodents. Additionally, some of these blockers of the renin-angiotensin system have been documented to enhance the anticonvulsant activity of antiepileptic drugs against maximal electroshock-induced seizures. The aim of the current study was to investigate the effect of aliskiren, a direct renin inhibitor and a novel antihypertensive drug, on the protective action of numerous antiepileptic drugs (carbamazepine, valproate, clonazepam, phenobarbital, oxcarbazepine, lamotrigine, topiramate and pregabalin) in the test of maximal electroshock in mice. The examined drugs were administered intraperitoneally. Aliskiren up to a dose of 75 mg/kg did not affect the threshold for electroconvulsions, however, aliskiren (75 mg/kg) enhanced the anticonvulsant action of clonazepam and valproate. Following aliskiren treatment, a higher brain concentration of valproate was noted, suggesting a pharmacokinetic interaction. In the rota-rod test, the concomitant treatment with aliskiren (50 or 75 mg/kg) and clonazepam (22.6 mg/kg) impaired motor coordination while clonazepam (22.6 mg/kg) alone showed strong tendency towards this impairment. The combination of aliskiren (75 mg/kg) with phenobarbital (25.5 mg/kg) caused long-term memory deficits in the passive avoidance task. This study shows that there are no negative interactions between aliskiren and the examined antiepileptic drugs as concerns their anticonvulsant activity. Aliskiren even potentiated the anticonvulsant action of clonazepam and valproate against maximal electroshock. The impact of aliskiren alone on seizure activity or on the anticonvulsant and adverse activity of antiepileptic drugs needs further evaluation in other animal models of seizures. [ABSTRACT FROM AUTHOR]

Discovery of potent renin inhibitors which contain a simplified alkylamino Asp-binding group and exhibit improved selectivity for renin over Cyp3A4 is described. Structure-function results in this series are rationalized based on analysis of selected compounds bound to renin, and the contribution of each molecular feature leading to the reduced P450 inhibition is quantified. [ABSTRACT FROM AUTHOR]

Renin is an aspartyl protease of the renin–angiotensin system (RAS) and the first enzyme of the biochemical pathway for the generation of angiotensin II – a potent vasoconstrictor involved in the maintenance of cardiovascular homeostasis and the regulation of blood pressure. High enzymatic specificity of renin and its involvement in the catalysis of the rate-limiting step of the RAS hormone system qualify it as a good target for inhibition of hypertension and other associated diseases. Ligand-based pharmacophore model (Hypo1) was generated from a training set of 24 compounds with renin inhibitory activity. The best hypothesis consisted of one Hydrogen Bond Acceptor (HBA), three Hydrophobic Aliphatic (HY-Al) and one Ring Aromatic (AR) features. This well-validated pharmacophore hypothesis (correlation coefficient 0.95) was further utilized as a 3D query to screen database compounds, which included structures from two natural product repositories. These screened compounds were further analyzed for drug-likeness and ADMET studies. The compounds which satisfied the qualifying criteria were then subjected to molecular docking and Density Functional Theory (DFT) analysis in order to discern their atomic level interactions at the active site of the 3D structure of rennin. The pharmacophore-based modelling that has been used to generate the novel findings of the present study would be an avant-garde approach towards the development of potent inhibitors of renin. [ABSTRACT FROM AUTHOR]

We have applied simulated annealing of chemical potential (SACP) to a diverse set of ∼150 very small molecules to provide insights into new interactions in the binding pocket of human renin, a historically difficult target for which to find low molecular weight (MW) inhibitors with good bioavailability. In one of its many uses in drug discovery, SACP provides an efficient, thermodynamically principled method of ranking chemotype replacements for scaffold hopping and manipulating physicochemical characteristics for drug development. We introduce the use of Constrained Fragment Analysis (CFA) to construct and analyze ligands composed of linking those fragments with predicted high affinity. This technique addresses the issue of effectively linking fragments together and provides a predictive mechanism to rank order prospective inhibitors for synthesis. The application of these techniques to the identification of novel inhibitors of human renin is described. Synthesis of a limited set of designed compounds provided potent, low MW analogs (IC 50 s < 100 nM) with good oral bioavailability (F > 20–58%). [ABSTRACT FROM AUTHOR]

• Aliskiren protects skin flap survival by inhibiting NLRP3-mediated pyroptosis. • NLRP3 inflammasome-inediated pyroptosis plays an important role in flap necrosis. • Angiogenesis, ischemia – reperfusion injury and inflammatory response are key factors of flap necrosis. Flaps are used in clinical wound repair, reconstruction, and plastic surgery but are prone to necrosis after surgery. Aliskiren, a direct renin inhibitor, may promote flap survival. Thirty-eight rats were divided into control and low- and high-dose aliskiren groups (n = 12 rats per group; two rats in the high-dose group died and were replaced). The flap survival rate, neutrophil density, microvessel density, superoxide dismutase activity, and malondialdehyde level were evaluated, and histopathological analysis was performed, on day 7 after surgery. Blood perfusion was measured by laser Doppler flowmetry and oxide-gelatin angiography. The levels of vascular endothelial growth factor, tumor necrosis factor-α, interleukin (IL)-6, Nod-like receptor 3, cysteinyl aspartate specific proteinase-1 (caspase-1), IL-1β, and IL-18 were evaluated by immunohistochemical analysis. Aliskiren improved flap survival. Downregulation of the malondialdehyde level and upregulation of the superoxide dismutase level in the experimental groups suggested that aliskiren reduced ischemia–reperfusion injury. Upregulation of the vascular endothelial growth factor level and improvement of blood perfusion in the experimental groups suggested that aliskiren improved flap angiogenesis. Immunohistochemical analysis showed that aliskiren reduced the levels of inflammatory factors such as tumor necrosis factor-α and IL-6. Furthermore, the expression of Nod-like receptor 3 inflammasome components was decreased in the experimental groups. Aliskiren improved the flap-survival rate. [ABSTRACT FROM AUTHOR]

To evaluate the prevalence of medication-related admissions (MRAs) and their association with potentially inappropriate medications (PIMs) used by nursing home residents admitted to the geriatric center of a tertiary hospital. Cross-sectional study. Older patients admitted from nursing homes to the geriatric center of the Seoul National University Bundang Hospital who had undergone comprehensive geriatric assessment from January 1, 2016, to December 31, 2020. MRAs were determined and verified using a previously described MRA adjudication guide. The PIMs in the preadmission medication lists were identified according to each of the following criteria (as well as the combined criteria), the Beers, NORGEP-NH, STOPP/START-NH, and STOPPFrail criteria. Medication use factors associated with MRAs were analyzed using multivariate logistic regression. Among the 304 acute care admissions, 32.2% were MRAs. The main cause of MRAs was acute kidney injury related with use of renin-angiotensin system inhibitors. Approximately 81% of the patients used at least 1 PIM according to the combined criteria. The use of 1 or more PIMs, renin-angiotensin system inhibitors, diuretics, nonsteroidal anti-inflammatory drugs, and benzodiazepines was significantly associated with MRAs. The combined criteria were able to predict MRAs better than the individual criteria. Approximately one-third of acute admissions of nursing home residents may be MRAs. Interventions for the optimal use of medication among nursing home residents are needed. [ABSTRACT FROM AUTHOR]

Background: In patients with diabetes, albuminuria is a risk marker of end-stage renal disease and cardiovascular events. An increased renin-angiotensin system activity has been reported to play an important role in the pathological processes in these conditions. We compared the effect of aliskiren, a direct renin inhibitor (DRI), with that of angiotensin receptor blockers (ARBs) on albuminuria and urinary excretion of angiotensinogen, a marker of intrarenal renin-angiotensin system activity. Methods: We randomly assigned 237 type 2 diabetic patients with high-normal albuminuria (10 to <30 mg/g of albumin-to-creatinine ratio) or microalbuminuria (30 to <300 mg/g) to the DRI group or ARB group (any ARB) with a target blood pressure of <130/80 mmHg. The primary endpoint was a reduction in albuminuria. Results: Twelve patients dropped out during the observation period, and a total of 225 patients were analyzed. During the study period, the systolic and diastolic blood pressures were not different between the groups. The changes in the urinary albumin-to-creatinine ratio from baseline to the end of the treatment period in the DRI and ARB groups were similar (-5.5% and -6.7%, respectively). In contrast, a significant reduction in the urinary excretion of angiotensinogen was observed in the ARB group but not in the DRI group. In the subgroup analysis, a significant reduction in the albuminuria was observed in the ARB group but not in the DRI group among high-normal albuminuria patients. Conclusion: DRI and ARB reduced albuminuria in hypertensive patients with type 2 diabetes. In addition, ARB, but not DRI, reduced albuminuria even in patients with normal albuminuria. DRI is not superior to ARB in the reduction of urinary excretion of albumin and angiotensinogen. [ABSTRACT FROM AUTHOR]

We compared the therapeutic effects of aliskiren (direct renin inhibitor (DRI) group) with angiotensin II (Ang II) type 1 receptor blockers (ARBs) (ARB group) on clinic blood pressure (BP) and ambulatory BP in 36 hypertensive chronic kidney disease (CKD) patients. The baseline clinic BP levels and the after-treatment/baseline (A/B) ratios of clinic BP levels, estimated after 24-week treatment period, were similar in DRI group (n= 18) and ARB group (n= 18). With respect to the effects on ambulatory BP, theA/Bratios of the daytime and nighttime systolic BP in DRI group were significantly higher than those in ARB group. TheA/Bratio of ankle-brachial pressure index after the study was higher in the DRI group compared with the ARB group. The results of the present study suggest that DRI therapy is not superior to ARB therapy in lowering ambulatory BP in hypertensive CKD patients, in spite of comparable clinic BP-lowering effects. [ABSTRACT FROM PUBLISHER]

Context:The health effects ofSambucus nigraL. (Caprifoliaceae) could be due to polyphenols whose modes of action differ from the traditional one proposed for exogenous antioxidants. Objective:The study emphasizes the effects of the association between the renin inhibitor and the polyphenolic extract on biochemical parameters and systolic (TAS) and diastolic (TAD) blood pressure within anLNAME-induced experimental model of arterial hypertension (AHT). Materials and methods:The polyphenols are extracted with ethanol from isolated and purified vegetable material represented by the mature fruit of theS. nigrawith a dosage of 0.046 g/kg body weight (PS), every 2 days, for 8 weeks. The dose represents 1/20 of LD50. The Wistar white rat blood pressure values were recorded using a CODA™ system, which uses a non-invasive blood pressure measuring method. Results and discussion:The total antioxidant capacity levels were significantly decreased (p < 0.001) in AHT group as compared to the rats in the AHT + PS group. A combination of a renin inhibitor (Aliskiren) and polyphenolic extract generated a superior antioxidant effect compared to administering the two separately. Both TAS and TAD in rats with drug-induced hypertension were reduced by polyphenolic extract. The homogeneous values of TAS record a significant decrease (p < 0.001) of the average values in AHT + PS group or AHT + Aliskiren group. Conclusion:The combination of two different classes of substances, namely, renin inhibitors and natural polyphenol extracts, reduces arterial pressure and also might reduce the side effects of the major classes of antihypertensive agents and improve the quality of live. [ABSTRACT FROM AUTHOR]

A novel approach was conducted for fragment-based lead discovery and applied to renin inhibitors. The biochemical screening of a fragment library against renin provided the hit fragment which showed a characteristic interaction pattern with the target protein. The hit fragment bound only to the S1, S3, and S3 SP (S3 subpocket) sites without any interactions with the catalytic aspartate residues (Asp32 and Asp215 (pepsin numbering)). Prior to making chemical modifications to the hit fragment, we first identified its essential binding sites by utilizing the hit fragment’s substructures. Second, we created a new and smaller scaffold, which better occupied the identified essential S3 and S3 SP sites, by utilizing library synthesis with high-throughput chemistry. We then revisited the S1 site and efficiently explored a good building block attaching to the scaffold with library synthesis. In the library syntheses, the binding modes of each pivotal compound were determined and confirmed by X-ray crystallography and the library was strategically designed by structure-based computational approach not only to obtain a more active compound but also to obtain informative Structure Activity Relationship (SAR). As a result, we obtained a lead compound offering synthetic accessibility as well as the improved in vitro ADMET profiles. The fragments and compounds possessing a characteristic interaction pattern provided new structural insights into renin’s active site and the potential to create a new generation of renin inhibitors. In addition, we demonstrated our FBDD strategy integrating highly sensitive biochemical assay, X-ray crystallography, and high-throughput synthesis and in silico library design aimed at fragment morphing at the initial stage was effective to elucidate a pocket profile and a promising lead compound. [ABSTRACT FROM AUTHOR]

The action of the aspartyl protease renin is the rate-limiting initial step of the renin-angiotensin-aldosterone system. Therefore, renin is a particularly promising target for blood pressure as well as onset and progression of cardiovascular and renal diseases. New pyrimidine derivatives 5 – 14 were designed in an attempt to enhance the renin inhibitory activity of compound 3 identified by our previous fragment-based drug design approach. Introduction of a basic amine essential for interaction with the two aspartic acids in the catalytic site and optimization of the S1/S3 binding elements including an induced-fit structural change of Leu114 (‘Leu-in’ to ‘Leu-out’) by a rational structure-based drug design approach led to the discovery of N -(piperidin-3-yl)pyrimidine-5-carboxamide 14 , a 65,000-fold more potent renin inhibitor than compound 3 . Surprisingly, this remarkable enhancement in the inhibitory activity of compound 14 has been achieved by the overall addition of only seven heavy atoms to compound 3 . Compound 14 demonstrated excellent selectivity over other aspartyl proteases and moderate oral bioavailability in rats. [ABSTRACT FROM AUTHOR]

Background/Aims: We have reported that the long-term administration of angiotensin II receptor blockers (ARBs) induced unusual proliferative changes of renal afferent arteriolar smooth muscle cells (SMCs) in rats, associated with the overproduction of renin. In this study, we examined that a direct renin inhibitor (DRI: Aliskilen; Novartis Pharma Co, USA) might induce different changes on afferent arteriolar walls compared to ARBs. Method: Twenty one 6-weeks-old male spontaneous hypertensive rats (SHRs) were divided into the following three groups: high-dose DRI group (n=7), low-dose DRI group (n=5) and control group (n=9). The rats were fed a standard diet (0.4%NaCl) containing high-dose (150mg/kg/day), low-dose (30mg/kg/day) DRI and without DRI for 12 weeks. The kidneys were examined by histological and immunohistochemical studies. Systolic blood pressure, 24-h urine samples and blood samples were also examined. Results: The afferent arteriolar SMC walls in the two DRI groups showed no proliferative changes. The positive renin expression area was the largest in the highdose DRI group among the three groups (14.3±4.0μm2, 6.7±2.0μm², 2.6±0.9µm²/glomerlus, p=0.020, p=0.008, p=0.017, respectively). Conclusion: The long-term DRI administration increases tissue and circulatory renin; however, afferent arteriolar proliferative changes as shown in ARBs were not induced. [ABSTRACT FROM AUTHOR]

Insulin resistance can occur as a consequence of heart failure (HF). Activation of the renin-angiotensin system (RAS) may play a crucial role in this phenomenon. We thus investigated the effect of a direct renin inhibitor, aliskiren, on insulin resistance in HF after myocardial infarction (MI). MI and sham operation were performed in male C57BL/6 J mice. The mice were divided into 4 groups and treated with sham-operation (Sham, n=10), sham-operation and aliskiren (Sham+Aliskiren; 10 mg/kg/day, n=10), MI (n=11), or MI and aliskiren (MI+Aliskiren, n=11). After 4 weeks, MI mice showed left ventricular dilation and dysfunction, which were not affected by aliskiren. The percent decrease of blood glucose after insulin load was significantly smaller in MI than in Sham (14±5% vs. 36±2%), and was ameliorated in MI+Aliskiren (34±5%) mice. Insulin-stimulated serine-phosphorylation of Akt and glucose transporter 4 translocation were decreased in the skeletal muscle of MI compared to Sham by 57% and 69%, and both changes were ameliorated in the MI+Aliskiren group (91% and 94%). Aliskiren administration in MI mice significantly inhibited plasma renin activity and angiotensin II (Ang II) levels. Moreover, (pro)renin receptor expression and local Ang II production were upregulated in skeletal muscle from MI and were attenuated in MI+Aliskiren mice, in tandem with a decrease in superoxide production and NAD(P)H oxidase activities. In conclusion, aliskiren ameliorated insulin resistance in HF by improving insulin signaling in the skeletal muscle, at least partly by inhibiting systemic and (pro)renin receptor-mediated local RAS activation, and subsequent NAD(P)H oxidase-induced oxidative stress. [ABSTRACT FROM AUTHOR]

Summary: The skeletal renin-angiotensin system contributes to the development of osteoporosis. The renin inhibitor aliskiren exhibited beneficial effects on trabecular bone of osteoporotic mice, and this action might be mediated through angiotensin and bradykinin receptor pathways. This study implies the potential application of renin inhibitor in the management for postmenopausal osteoporosis. Introduction: The skeletal renin-angiotensin system plays key role in the pathological process of osteoporosis. The present study is designed to elucidate the effect of renin inhibitor aliskiren on trabecular bone and its potential action mechanism in ovariectomized (OVX) mice. Methods: The OVX mice were treated with low dose (5 mg/kg) or high dose (25 mg/kg) of aliskiren or its vehicle for 8 weeks. The bone turnover markers were measured by ELISA. The structural parameters of trabecular bone at lumbar vertebra (LV) and distal femoral metaphysis were measured by micro-CT. The expression of messenger RNA (mRNA) and protein was studied by RT-PCR and immunoblotting, respectively. Results: Aliskiren treatment reduced urinary excretion of calcium and serum level of tartrate-resistant acid phosphatase in OVX mice. The treatment with aliskiren significantly increased bone volume (BV/TV) and connectivity density (Conn.D) of trabecular bone at LV-2 and LV-5 as well as dramatically enhanced BV/TV, Conn.D, bone mineral density (BMD/BV) and decreased bone surface (BS/BV) at the distal femoral end. Aliskiren significantly down-regulated the expression of angiotensinogen, angiotensin II (Ang II), Ang II type 1 receptor, bradykinin receptor (BR)-1, and osteocytic-specific gene sclerostin as well as the osteoclast-specific genes, including carbonic anhydrase II, matrix metalloproteinase-9, and cathepsin K. Conclusions: This study revealed that renin inhibitor aliskiren exhibited the beneficial effects on trabecular bone of ovariectomy-induced osteoporotic mice, and the underlying mechanism for this action might be mediated through Ang II and BR signaling pathways in bone. [ABSTRACT FROM AUTHOR]

It is well known that endogenous bioactive proteins and peptides play a substantial role in the body's first line of immunological defence, immune-regulation and normal body functioning. Further, the peptides derived from the luminal digestion of proteins are also important for body function. For example, within the peptide database BIOPEP ( http://www.uwm.edu.pl/biochemia/index.php/en/biopep ) 12 endogenous antimicrobial and 64 angiotensin-I-converting enzyme (ACE-I) inhibitory peptides derived from human milk and plasma proteins are listed. The antimicrobial peptide database ( http://aps.unmc.edu/AP/main.php ) lists over 111 human host-defence peptides. Several endogenous proteins are secreted in the gut and are subject to the same gastrointestinal digestion processes as food proteins derived from the diet. The human gut endogenous proteins (GEP) include mucins, serum albumin, digestive enzymes, hormones, and proteins from sloughed off epithelial cells and gut microbiota, and numerous other secreted proteins. To date, much work has been carried out regarding the health altering effects of food-derived bioactive peptides but little attention has been paid to the possibility that GEP may also be a source of bioactive peptides. In this review, we discuss the potential of GEP to constitute a gut cryptome from which bioactive peptides such as ACE-I inhibitory, renin inhibitory and antioxidant peptides may be derived. [ABSTRACT FROM AUTHOR]

Hypertension is the main cause of human death and the Renin- Angiotensin- Aldosterone System (RAAS) has a key role in the control of human blood pressure. In this research a multi-step virtual screening strategy was applied in order to find new potential renin inhibitors. The crystal structure of renin-aliskiren complex was explored and receptor-ligand pharmacophore model was developed and validated using pharmit. ZINC database was screened by pharmacophore model and Lipinski's rule of five. Thereafter, the retrieved hits were docked in the active site of renin by using Vina. ADME parameters and toxicity of the filtered compounds were approximated using in silico methods and the selected compounds were subjected to high performance docking in order to improve the accuracy of screening. The non-bond interactions of the hit molecules with renin were explored and the compounds with the highest affinity and appropriate interactions were selected. In the last step, molecular dynamic simulation studies were performed on the complex of renin with aliskiren and three top-ranked structures including ZINC6085004, ZINC426421106, and ZINC5481346. RMSD, RMSF, Rg and number of hydrogen bonds were calculated. The binding free energy was calculated using the MM/PBSA method. The result of MD simulation indicated the stable binding of ZINC426421106 and ZINC5481346 with the active site of renin. According to this in-silico study these two compounds are drug-like, nontoxic, and have a high potential for inhibiting renin and could serve as appropriate lead molecules for the development of renin inhibitors as antihypertensive agents. Representation of the overall virtual screening process. [Display omitted] • A structure-based pharmacophore model was developed and validated for the renin-aliskiren complex. • ZINC database was screened by the pharmacophore model. • Molecular dynamic simulation studies were performed on the complex of renin with top-ranked structures. • The binding free energy was calculated using the MM/PBSA method. • Two molecules had a high potential for inhibition of human renin. [ABSTRACT FROM AUTHOR]

To exploit the S3′ subsite of renin active site for renin inhibitor design, 42 aliskiren derivatives with modified P2′ portion were designed, synthesized and biologically evaluated. Some highly potent renin inhibitors (IC 50 < 3 nM) were identified, among which compounds 38 (IC 50 = 0.9 nM) and 39 (IC 50 = 0.7 nM) were over 2.5-fold more potent than aliskiren (IC 50 = 2.3 nM). SAR analysis indicated that incorporation of polar hydrophilic moieties into the P2′ portion of renin inhibitors generally enhanced the potency. Consistently with this, molecular modeling study revealed that the triazole part of 39 could provide additional interactions to the S3′ subsite of renin active site. Moreover, in vivo evaluation in the double transgenic mouse hypertension model demonstrated that 39 produced greater reduction of the mean arterial blood pressure than ariskiren at the doses of 17.0 and 34.0 μmol/kg, respectively. Taken together, the S3′ subsite of renin active site merits further consideration for renin inhibitor design. [ABSTRACT FROM AUTHOR]

Background/Aims: The purpose of the present study was to compare the direct renin inhibitor aliskiren to the diuretic hydrochlorothiazide (HCTZ) in their ability to modulate renal tissue oxygenation in hypertensive patients. Methods: 24 patients were enrolled in this randomized prospective study and 20 completed the protocol. Patients were randomly assigned to receive either aliskiren 150-300 mg/d or HCTZ 12.5 - 25 mg/d for 8 weeks. Renal oxygenation was measured by BOLD-MRI at weeks 0 and 8. BOLD-MRI was also performed before and after an i.v. injection of 20 mg furosemide at week 0 and at week 8. BOLD-MRI data were analyzed by measuring the oxygenation in 12 computed layers of the kidney enabling to asses renal oxygenation according to the depth within the kidney and by the classical method of regions of interest (ROI). Results: The classical ROI analysis of the data showed no difference between the groups at week 8. The analysis of renal oxygenation according to the 12 layers method shows no significant difference between aliskiren and HCTZ at week 8 before administration of furosemide. However, within group analyses show that aliskiren slightly but not significantly increased oxygenation in the cortex and decreased medullary oxygenation whereas HCTZ induced a significant overall decrease in renal tissue oxygenation. With the same method of analysis we observed that the response to furosemide was unchanged in the HCTZ group at week 8 but was characterized by an increase in both cortical and medullary oxygenation in aliskiren-treated patients. Patients responding to aliskiren and HCTZ by a fall in systolic blood pressure of >10 mmHg improved their renal tissue oxygenation when compared to non-responders. Conclusion: With the classical method of evaluation using regions no difference were found between aliskiren and HCTZ on renal tissue oxygenation after 8 weeks. In contrast, with our new method that takes into account the entire kidney, within group analyses show that aliskiren slightly increases cortical and medullary renal tissue oxygenation in hypertensive patients whereas HCTZ decreases significantly renal oxygenation at trough. © 2015 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Increased activity of the renin-angiotensin-aldosterone system (RAAS) plays a significant role in the development and progression of various cardio-metabolic diseases, such as hypertension, atherosclerosis and heart failure. Aliskiren is the newest antihypertensive drug and the first orally active direct renin inhibitor to become available for clinical use. This study investigated the acute and direct effects of Aliskiren on different parameters of oxidative stress on isolated rat heart. The hearts of male Wistar albino rats (n = 24, 8 per experimental group, age 8 weeks, body mass 180-200 g), were excised and retrogradely perfused according to the Langendorfftechnique at a gradually increasing perfusion pressure (40-120 cmH2O). Markers of oxidative stress (NO2−, TBARS, H2O2 and O2−) were measured spectrophotometrically after perfusion with three different concentrations of Aliskiren (0.1 μM, 1 μM, and 10 μM). The results demonstrated possible dose-dependent cardioprotective properties of Aliskiren, particularly with higher CPP. Lipid peroxidation (TBARS) levels decreased with the highest dose of Aliskiren and higher CPP, and the same trend was observed in nitrite (NO2−) and hydrogen peroxide (H2O2) levels. These findings indicate that the acute effects of Aliskiren do not likely promote the production of reactive oxygen species upon higher pressure with the highest dose. Aliskiren may exert beneficial effects on oxidative stress biomarkers. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to analyze the hemodynamic and cardiac effects of direct renin inhibitor (DRI) treatment and swimming training in hypertensive rats. Methods: Seventy-seven rats were divide into eight groups: sedentary normotensive (SN), trained normotensive (TN), sedentary normotensive treated with DRI (SN_DRI), trained normotensive treated with DRI (TN_DRI), sedentary hypertensive (SH), trained hypertensive (TH), sedentary hypertensive treated with DRI (SH_DRI), trained hypertensive treated with DRI (TH_DRI). Swimming training occurred for up to 60min, five times a week for four weeks. The hypertensive animals were treated with 20 mg · kg-1 · day-1 L-NAME for four weeks. Groups treated with DRI received 10mg · kg-1 · day-1 of aliskiren for four weeks. After the treatment period, all the animals underwent femoral artery catheterization surgery for direct measurement of cardiovascular variables. Results: The SH group presented hypertension (136.4±5.0mmHg) compared to the SN (107.1 ±1.7mmHg). The TH group showed lower mean arterial pressure (MAP) than the SH (121.1 ±1.3 mmHg), but the treatment with DRI did not attenuate hypertension (128.2 ± 4.9 mmHg). The analysis of collagen areas demonstrated that treatment with DRI may attenuate cardiac remodeling in situations of hypertension, in the condition of treatment alone or combined with physical training. Conclusion: Both interventions in combination may be more effective at reducing cardiovascular risk in hypertensive subjects. [ABSTRACT FROM AUTHOR]