Functional candesartan loaded lipid nanoparticles for the control of diabetes-associated stroke: In vitro and in vivo studies

Diabetes mellitus is a metabolic disease that raises the odds of developing stroke. Candesartan has been used to prevent stroke due to its inhibitory effects on blood pressure, angiogenesis, oxidative damage, and apoptosis. However, oral candesartan has very limited bioavailability and efficacy due to its weak solubility and slow release. The study aimed to develop a nasal formulation of candesartan-loaded liposomes containing ethanol and propylene glycol (CLEP) to improve candesartan's delivery, release, permeation, and efficacy as a potential diabetes-associated stroke treatment. Using design expert software, different CLEP formulations were prepared and evaluated in vitro to identify the optimum formulation, which. The selected optimum formulation composed of 3.3% phospholipid, 10% ethanol, and 15% propylene glycol significantly increased the release and permeation of candesartan relative to free candesartan by a factor of 1.52 and 1.47, respectively. The optimum formulation significantly reduced the infarction after stroke in rats; decreased flexion, spontaneous motor activity, and time spent in the target quadrant by 70%, 64.71%, and 92.31%, respectively, and enhanced grip strength by a ratio of 2.3. Therefore, nasal administration of the CLEP formulation could be a potential diabetes-associated stroke treatment.

Impact of prior antihypertensive treatment on COVID-19 outcomes, by active ingredient

OBJECTIVES

To assess the impact of prior chronic treatment with angiotensin-converting enzyme inhibitors (ACEIs)/ angiotensin-receptor blockers (ARBs), both as a group and by active ingredient, on severity (risk of hospitalization and mortality), progression of and susceptibility to COVID-19.

METHODS

We conducted a multiple population-based case-control study in Galicia (north-west Spain). The study data were sourced from medical, administrative and clinical databases. We assessed: (1) risk of hospitalization, by selecting all patients hospitalized due to COVID-19 with PCR + as cases, and a random sample of subjects without a PCR + as controls; (2) COVID-19 mortality risk; (3) risk of disease progression; and (4) susceptibility to SARS-CoV-2, considering all patients with PCR + as cases, and the same subjects used in the previous model as controls. Adjusted odds ratios (aORs) were calculated.

RESULTS

ACEIs and ARBs were shown to decrease the risk of hospitalization (aOR = 0.78 [95%CI 0.69-0.89] and aOR = 0.80 [95%CI 0.72-0.90] respectively), risk of mortality (aOR = 0.71 [95%CI 0.52-0.98] and aOR = 0.69 [95%CI 0.52-0.91] respectively), and susceptibility to the virus (aOR = 0.88 [95%CI 0.82-0.94] and aOR = 0.92 [95%CI 0.86-0.97] respectively). By active ingredient: use of enalapril was associated with a significantly lower risk of hospitalization (aOR = 0.72 [95%CI 0.61-0.85]), mortality (aOR = 0.59 [95%CI 0.38-0.92]) and susceptibility to COVID-19 (aOR = 0.86 [95%CI 0.79-0.94]); and use of candesartan was associated with a decreased risk of hospitalization (aOR = 0.76 [95%CI 0.60-0.95]), mortality (aOR = 0.36 [95%CI 0.17-0.75]) and disease progression (aOR = 0.73 [95%CI 0.56-0.95]).

CONCLUSION

This large-scale real-world data study suggest that enalapril and candesartan are associated with a considerable reduction in risk of severe COVID19 outcomes.

Achieved dose and treatment discontinuation of candesartan in men and women with chronic heart failure: data from CHARM

AIMS

Angiotensin receptor blockers have been shown to reduce heart failure hospitalization and cardiovascular mortality in men and women with heart failure with reduced ejection fraction (HFrEF). It is unknown whether there are differences between men and women in achieved dose and treatment discontinuation due to adverse events of candesartan.

METHODS AND RESULTS

We conducted a post hoc analysis of the Candesartan in Heart failure: Assessment of Reduction in Mortality and morbidity (CHARM) programme. A total of 3172 men and 1106 women with HFrEF [left ventricular ejection fraction (LVEF) ≤ 40%] in New York Heart Association class II-IV were randomized to candesartan or placebo. Every 2 weeks, patients were up-titrated from 4 or 8, to16, to 32 mg once daily, unless a higher dose was contraindicated or not tolerated. Women were older (66 vs. 64 years), had a higher LVEF (29.9% vs. 28.6%), and had more hypertension (54% vs. 47%) than men. The mean achieved dose of candesartan was 21.5 ± 12.6 mg in men and 20.7 ± 12.9 mg in women (P = 0.19). In both the candesartan and placebo groups, cardiovascular death and heart failure hospitalizations were higher in men and women who achieved lower dose levels. Event rates for achieved dose levels of 0, 4 or 8, 16, and 32 mg candesartan were 20.8, 17.2, 14.0, and 10.1 per 100 person-years in men, respectively, and 23.6, 13.7, 14.0, and 9.1 per 100 person-years in women, respectively. In each of the achieved dose levels, there was no sex difference in the proportion of patients with an event, neither in the candesartan group nor in the placebo group (P-value for all > 0.05). There was no significant interaction between sex and treatment-related discontinuation for hypotension (P = 0.520), an increase in creatinine (P = 0.102), and hyperkalaemia (P = 0.905).

CONCLUSIONS

In a randomized clinical trial in patients with HFrEF, men and women achieved similar doses of candesartan. Primary event rates and treatment-related discontinuation due to adverse events were also similar between men and women.

Telmisartan and candesartan promote browning of white adipose tissue and reverse fatty liver changes in high fat diet fed male albino rats

Obesity is a key risk factor for many diseases, as cardiovascular disorders, diabetes, infertility, osteoarthritis, sleep apnea, non-alcoholic fatty liver disease (NAFLD) as well as increased risk for many cancers. Telmisartan and Candesartan cilexetil are angiotensin II receptor blockers which had proven to involve in pathogenesis of obesity and NAFLD.

AIMS

This work is designed to explore the possible mitigated effects of Telmisartan and Candesartan cilexetil on weight gain and fatty liver in high fat diet (HFD) fed rats.

MAIN METHODS

The HFD rat model was achieved with induction of NAFLD. For Seven weeks either telmisartan or candesartan were orally administered at doses of 5 and 10 mg/kg respectively once daily. The effects of both drugs were evaluated by measurements of rat's body weight, food intakes, length, body mass index (BMI), liver weight, inguinal and interscapular fat weights. In addition, we assayed lipid profile, liver functions tests, serum inflammatory cytokines, adipokine and leptin. Lastly, liver and adipose tissue histopathological structures were evaluated.

KEY FINDINGS

at end of experiment, telmisartan and candesartan were highly effective in decreasing rat's body weight from (213.1±2.68 to 191.2±2.54 and 203.5±5.89 gm , respectively), BMI, liver weight, fat weights in addition reduced serum levels of lipid and liver enzymes. Also, inflammatory cytokines were reduced with repaired histopathological insults in liver by significantly damped NAFLD score from (6.5 ±0.17 to 1±0 and 4 ±0, respectively) and decreased areas of adipocytes from (21239.12 to 5355.7 and 11607.1 um2 , respectively).

SIGNIFICANCE

Telmisartan and candesartan have therapeutic potential against obesity and NAFLD induced by HFD in rats. All the previous indices showed more improvement in telmisartan than candesartan group.

Design, optimization, and in vivo evaluation of invasome-mediated candesartan for the control of diabetes-associated atherosclerosis

Atherosclerosis is an inflammatory disease characterized by the accumulation of arterial plaque. Diabetes mellitus stands out as a major risk factor for atherosclerosis. Candesartan is a potent angiotensin II receptor antagonist that enhances arterial blood flow and reduces insulin resistance. However, oral candesartan has limited activity because of its low bioavailability, water solubility, hepatic first-pass degradation, and efficacy. The current study aims to develop nasal candesartan-loaded invasome (CLI) drops to improve candesartan's permeation, release, and bioavailability as a potential treatment for diabetes-associated atherosclerosis. Design expert software was used to prepare various CLI formulations to determine the impact of the concentrations of ethanol, cineole, and phospholipid. The desirability index was used to estimate the optimized formulation composition to maximize entrapment efficiency and minimize vesicle size. The optimized formulation had a 1% ethanol concentration, a 1.5% cineole concentration, and a 2.32% phospholipid concentration. The selected optimized formulation was then tested in a rat model of diabetes and atherosclerosis to evaluate its activity. The results showed that nasal CLI drops significantly raised serum HDL levels by a ratio of 1.42 and lowered serum glucose, cholesterol, triglycerides, LDL, and VLDL levels by 69.70%, 72.22%, 36.52%, 58.0%, and 65.31%, respectively, compared with diabetic atherosclerotic rats, throwing an insight on the potential for promising anti-diabetic and anti-atherosclerotic activities. Additionally, atherosclerotic lesions were improved in rats treated with CLI, as shown in histopathology. In conclusion, the results of this investigation showed that treatment with nasal CSN-loaded invasome formulation drops prevented the initiation and progression of diabetes-associated atherosclerosis.

Therapeutic effects of candesartan in inflammatory skin disorders by suppressing Th17 differentiation

As angiotensin II is associated with inflammation, type I angiotensin II receptor blockers (ARBs) exibit anti-inflammatory effects in patients with hypertension as well as inflammatory disease animal models including arthritis models. The present study aimed to investigate whether ARBs exert anti-inflammatory effects in vivo in skin disorders. We tested effects of ARBs on 1-chloro-2,4-dinitrobenzene(CDNB)-induced atopic dermatitis-like and imiquimod-induced psoriasis-like skin models. CDNB-induced atopic dermatitis-like skin lesions were suppressed by administration of candesartan or telmisartan. The suppressive effect of telmisartan was blocked by the presence of GW9662, a selective PPARγ inhibitor, but not that of candesartan. Both ARBs suppressed increases in pro-inflammatory cytokine (IL-4, IL-13, IFN-γ, and IL-17A) levels, and GW9662 inhibited telmisartan-induced suppression but not candesartan. Candesartan significantly inhibited in vitro differentiation of naïve T cells into Th17 cells to a greater extent than telmisartan. In the imiquimod-induced psoriasis model, whose primary etiology is activation of IL-23/IL-17 axis, candesartan significantly suppressed psoriasis-like skin lesions and Th17 cell populations in both lymph nodes and spleens to a greater extent than telmisartan. Overall, certain ARBs may have anti-inflammatory effects in skin diseases. Candesartan may have therapeutic implications in inflammatory skin disorders by suppressing Th17 differentiation, while telmisartan might have therapeutic potential by activating PPARγ.

Cost-utility analysis of valsartan, enalapril, and candesartan in patients with heart failure in Iran

BACKGROUND

Today, heart failure is one of the leading causes of death and disability in most developed and developing countries. By 2030, more than 23.3 million people are projected to die of cardiovascular diseases each year, and the prevalence of heart failure is expected to increase by 25%. One of the preventive interventions is pharmacological interventions which can be used to reduce the complications of cardiovascular diseases such as heart failure. One of the most important pharmacological interventions in patients with heart failure is the use of antihypertensive drugs such as candesartan, enalapril, and valsartan. This study aimed to compare the cost-utility of candesartan, enalapril, and valsartan in patients with heart failure using the Markov model in Iran in 2020.

METHODS

In the present study, a four-state Markov model was designed to compare the cost-utility of candesartan, enalapril, and valsartan for a hypothetical cohort of 10,000 heart failure patients older than 24 years. The payers' perspective was used to calculate the costs. The Markov states included outpatients with heart failure, patients with heart failure admitted to general hospital wards, patients with heart failure admitted to the intensive care units (ICUs), and death. The effectiveness measure in this study was the quality-adjusted life years (QALYs). The one-way and probabilistic sensitivity analyses were used to determine the robustness of the results. The TreeAge Pro 2011 software was used for data analysis.

RESULTS

The results showed that the average expected costs and QALYs were 119645.45 USD and 16.15 for valsartan, 113,019.68 USD and 15.16 for enalapril, and 113,093.37 USD and 15.06 for candesartan, respectively. Candesartan was recognized as the dominated option. Because the calculated incremental cost-effectiveness ratio (ICER) value (6,692.69 USD) was less than the threshold value (7,256 USD), valsartan was cost-effective compared to enalapril. The results of the cost-effectiveness acceptability curve showed that at the threshold of 7,256 USD, valsartan had a 60% chance of being cost-effective compared to enalapril. The results of one-way and probabilistic sensitivity analyses confirmed the robustness of the results. Moreover, the results showed that ICU (1,112 USD) had the highest cost among cost items.

CONCLUSION

According to the results, it is recommended that health policymakers consider the use of valsartan by cardiologists when designing clinical guidelines for the treatment of patients with heart failure.

Candesartan exhibits low intrinsic permeation capacity and affects buccal tissue viability and integrity: An ex vivo study in porcine buccal mucosa

Candesartan is a nonpeptide angiotensin II receptor blocker that selectively binds to angiotensin II receptor subtype 1. It is administered orally in its ester form (candesartan cilexetil). However, its poor aqueous solubility results in its low bioavailability; therefore, other routes of administration must be explored. The buccal mucosa has been extensively studied as an alternative route for drug delivery as it improves the bioavailability of drugs administered via the peroral route. Porcine buccal mucosa has been widely used as an ex vivo model to study the permeability of various diffusants; however, studies on candesartan are limited. This study aimed to evaluate the ex vivo permeation profile of candesartan and its effects on the viability and integrity of porcine buccal mucosa. Initially, we evaluated the viability, integrity, and barrier function of the buccal tissue before performing permeability tests using freshly excised tissues or tissues after 12 h of resection. Here, three indicators were used: caffeine, β-estradiol, and FD-20 penetration; mucosal metabolic activity, as determined using MTT reduction assay; and haematoxylin and eosin staining. Our results indicated that the porcine buccal mucosa preserved its viability, integrity, and barrier function before the permeation assay, allowing the passage of molecules with a molecular mass of less than 20 kDa, such as caffeine, but not β-estradiol and FD-20. Furthermore, we analyzed the intrinsic capacity of candesartan to diffuse through the fresh porcine buccal mucosa under two pH conditions. The concentration of candesartan in the receptor chamber of Franz diffusion cell was quantified using ultra-high liquid chromatography. In the permeation assay, candesartan exhibited a low intrinsic permeation capacity that impacted the buccal tissue viability and integrity, suggesting that using the buccal mucosa as an alternative route of administration requires developing a pharmaceutical formulation that reduces the adverse effects on mucosa and increasing the buccal permeability of candesartan.

Candesartan Protects Against Cadmium-Induced Hepatorenal Syndrome by Affecting Nrf2, NF-κB, Bax/Bcl-2/Cyt-C, and Ang II/Ang 1-7 Signals

Cadmium (Cd) is a serious pollutant in the environment. Candesartan is an angiotensin II (Ang II) receptor antagonist with promising diverse health benefits. The current study is planned to investigate the hepatorenal protective effects of candesartan against Cd-induced hepatic and renal intoxication. Our results demonstrated that candesartan effectively attenuated Cd-induced hepatorenal intoxication, as evidenced by improving hepatic and renal function biomarkers. Besides, candesartan reversed hepatic and renal histopathological abrasions induced by Cd toxicity. Candesartan antioxidant effect was mediated by Nrf2 activation. Also, candesartan suppressed hepatorenal inflammation by modulating NF-κB/IκB. Moreover, candesartan attenuated Cd hepatorenal apoptosis by upregulating Bcl-2 and downregulating Bax and Cyt-C proteins. Interestingly, these effects are suggested to be an outcome of modulating of Ang II/Ang 1-7 signal. Overall, our findings revealed that candesartan could attenuate Cd-induced hepatorenal intoxication through modulation of Nrf2, NF-κB/IκB, Bax/Bcl-2/Cyt-c, and Ang II/Ang 1-7 signaling pathways.

Candesartan protects against unilateral peripheral limb ischemia in type-2 diabetic rats: Possible contribution of PI3K-Akt-eNOS-VEGF angiogenic signaling pathway

Type-2 diabetes (T2DM) is known to be highly associated with increased risk for vascular complications including peripheral arterial diseases (PAD). Critical limb ischemia (CLI) is the most advanced stage of PAD. Current therapeutic options for diabetic patients experiencing vascular complications are limited to surgical revascularization with no effective pharmacotherapy available for clinical settings. This study is dedicated to evaluate the angiogenic potential of candesartan an angiotensin-II receptor blocker in an experimental model of vascular complications associating T2DM. T2DM was induced in rats through feeding with high fat diet for 6 weeks, followed by injection with streptozotocin (STZ, 30 mg/kg; i.p). After establishment of T2DM, unilateral CLI was induced through the ligation and excision of superficial femoral artery. Candesartan treatment (10 or 30 mg/kg; orally) was initiated one day post CLI and thereafter once daily for up to 14 days. T2DM rats that underwent CLI demonstrated impaired angiogenic signaling, increased inflammation and apoptosis in gastrocnemius muscle (GC). Candesartan reversed ischemic insult in T2DM rats subjected to unilateral CLI and induced reparative angiogenesis that was evident by increase in p-PI3K/PI3K, p-Akt/Akt, p-eNOS/eNOS, p-VEGFR2/VEGFR2 ratios, and VEGF levels. Candesartan treatment also increased levels of HO-1; while decreased caspase-3 apoptotic marker and levels of inflammatory markers; NF-κB and TNF-α, all of which were accompanied by preserved histological manifestations of GC muscles. Candesartan was able to combat limb ischemia under diabetic conditions which could pave the way for its therapeutic utility for diabetic patients experiencing vascular complications in clinical setting.

Drug repurposing and molecular mechanisms of the antihypertensive drug candesartan as a TMEM16A channel inhibitor

TMEM16A, a Ca²⁺-activated chloride channel (CaCC), and its pharmacological inhibitors can inhibit the growth of lung adenocarcinoma cells. However,the poor efficacy, safety, and stability of TMEM16A inhibitors limit the development of these agents. Therefore, finding new therapeutic directions from already marketed drugs is a feasible strategy to obtain safe and effective therapeutic drugs. Here, we screened a library contain more than 2400 FDA, EMA, and NMPA-approved drugs through virtual screening. We identified a drug candidate, candesartan (CDST), which showed strong inhibitory effect on the TMEM16A in a concentration-dependent manner with an IC₅₀ of 24.40 ± 3.21 μM. In addition, CDST inhibited proliferation, migration and induced apoptosis of LA795 cells targeting TMEM16A, and significantly inhibited lung adenocarcinoma tumor growth in vivo. The molecular mechanism of CDST inhibiting TMEM16A channel indicated it bound to R515/R535/E623/E624 in the drug pocket, thereby blocked the pore. In conclusion, we identified a novel TMEM16A channel inhibitor, CDST, which exhibited excellent inhibitory activity against lung adenocarcinoma. Considering that CDST has been used in clinical treatment of hypertension, it may play an important role in the combined treatment of hypertension and lung adenocarcinoma as a multi-target drug in the future.

Effects of candesartan on cerebral microvascular function in mild cognitive impairment: Results of two clinical trials

BACKGROUND

Cerebral microvascular dysfunction is commonly seen in Alzheimer's disease (AD) and vascular cognitive impairment (VCI). Cerebrovascular reactivity (CVR) to CO₂ reflects cerebral microvascular health and may be modulated by the renin-angiotensin system (RAS). This study aimed to investigate the effects of RAS modulation on CVR in individuals with mild cognitive impairment (MCI) due to underlying vascular or AD etiologies.

METHODS

This study presents findings of candesartan's effects on the secondary outcomes of two double-blind randomized clinical trials of 12-month therapy of candesartan versus lisinopril in VCI (CALIBREX (Candesartan vs Lisinopril Effects on the Brain and Endothelial Function in Executive MCI)) and candesartan versus placebo in prodromal AD (Candesartan's Effects on Alzheimer's Disease and Related Biomarkers (CEDAR)). Primary outcome results of these trials have been reported in previous publications. Participants underwent identical brain blood oxygenation level dependent (BOLD)-CVR in response to a 2-min CO₂ challenge at baseline and 12 months. Regions of interest and voxel-wise CVR maps were derived from BOLD signal changes during CO₂ challenge. CVR effects were compared between candesartan and lisinopril (CALIBREX) and candesartan and placebo (CEDAR) using mixed-model repeated measures.

RESULTS

Data from 102 participants in the CALIBREX study (mean age = 65 years, 45% female, 63% African American) and 59 in the CEDAR study (mean age = 67 years, 32% female, 20% African American) were analyzed. Candesartan was associated with improved whole brain CVR compared to placebo in the CEDAR study (adjusted within-group mean difference for candesartan = 0.27 (95% confidence interval (CI) = 0.006, 0.53) vs placebo = -0.17 (95% CI = 0.42, 0.08), p-value = 0.018), and compared to lisinopril in the CALIBREX study (adjusted within-group mean difference for candesartan = 0.28 (95% CI = 0.10, 0.46) vs lisinopril = -0.08 (95% CI = -0.31, 0.14), p-value = 0.012), independent of blood pressure. In an exploratory meta-analysis of the two trials, improved CVR in the hippocampus was linked to improved attention and working memory (p = 0.044) and a trend for improved executive function (p = 0.087) with candesartan therapy.

CONCLUSION

This study suggests that candesartan is associated with improved microvascular function in MCI, and these findings are independent of its blood pressure effect in these VCI and prodromal AD populations.

Pharmacogenomic study of heart failure and candesartan response from the CHARM programme

AIMS

The Candesartan in Heart failure Assessment of Reduction in Mortality and morbidity (CHARM) programme consisted of three parallel, randomized, double-blind clinical trials comparing candesartan with placebo in patients with heart failure (HF) categorized according to left ventricular ejection fraction and tolerability to an angiotensin-converting enzyme inhibitor. We conducted a pharmacogenomic study of the CHARM trials with the objective of identifying genetic predictors of HF progression and of the efficacy and safety of treatment with candesartan.

METHODS

We performed genome-wide association studies in 2727 patients of European ancestry from CHARM-Overall and stratified by CHARM study according to preserved and reduced ejection fraction and according to assignment to the interventional treatment with candesartan. We tested genetic association with the composite endpoint of cardiovascular death or hospitalization for heart failure for drug efficacy in candesartan-treated patients and for HF progression using patients from both candesartan and placebo arms. The safety endpoints for response to candesartan were hyperkalaemia, renal dysfunction, hypotension, and change in systolic blood pressure between baseline and 6 weeks of treatment. To support our observations, we conducted a genome-wide gene-level collapsing analysis from whole-exome sequencing data with the composite cardiovascular endpoint.

RESULTS

We found that the A allele (14% allele frequency) of the genetic variant rs66886237 at 8p21.3 near the gene GFRA2 was associated with the composite cardiovascular endpoint in 1029 HF patients with preserved ejection fraction from the CHARM-Preserved study (hazard ratio: 1.91, 95% confidence interval: 1.55-2.35; P = 1.7 × 10^-9 ). The association was independent of candesartan treatment, and the genetic variant was not associated with the cardiovascular endpoint in patients with reduced ejection fraction. None of the genome-wide association studies for candesartan safety or efficacy conducted in patients treated with candesartan passed the significance threshold. We found no significant association from the gene-level collapsing analysis.

CONCLUSIONS

We have identified a candidate genetic variant potentially predictive of the progression of heart failure in patients with preserved ejection fraction. The findings require further replication, and we cannot exclude the possibility that the results may be chance findings.

Contralesional angiotensin type 2 receptor activation contributes to recovery in experimental stroke

We and others have previously shown that angiotensin II receptor type 2 receptor (AT2R) is upregulated in the contralesional hemisphere after stroke in normoglycemic Wistar rats. In this study, we examined the expression of AT2R in type 2 diabetic Goto-Kakizaki (GK) rats and control Wistars after stroke. We also tested the contribution of the contralesional AT2R in recovery after stroke through a specific knockdown of the AT2R in this hemisphere only. Two experiments were conducted. In the first experiment, GK rats were subjected to middle cerebral artery occlusion (MCAO) and treated with the angiotensin II receptor type 1 receptor (AT1R) blocker candesartan or saline at reperfusion. Stroke outcomes, as well as AT2R expression, were examined and compared to control Wistars at 24 h. In the second experiment, localized AT2R knockdown was achieved through intrastriatal injection of short hairpin RNA (shRNA) lentiviral particles or non-targeting control into the left-brain hemisphere of Wistar rats. After 14 days, rats were subjected to right MCAO and treated with the AT2R agonist, Compound 21 (C21), or saline for 7 days. Behavioral outcomes were assessed for up to 10 days. In the first experiment, stroke reduced the expression of AT2R in GK rats. Candesartan treatment failed to improve the neurobehavioral outcomes, preserve vascular integrity or reduce oxidative/nitrative stress or apoptotic markers at 24 h post stroke in these animals. In the second experiment, contralesional AT2R knockdown reduced the C21-mediated functional recovery after stroke. In conclusion, contralesional AT2R upregulation after stroke is blunted in diabetic rats which show reduced sensitivity to post-stroke candesartan treatment. Contralesional AT2R could be involved in C21-mediated functional recovery after stroke.

The power of High Impact Amplitude Manipulation (HIAM) technique for extracting the basic spectra of two Fixed-dose combinations (FDC) -Spectrophotometric purity analysis via spectral contrast angle

HIAM technique allows the extraction of the original constant signal of each single component out of interference signals of a mixture and further transformed into basic spectrum (D⁰). It includes the methods: ratio subtraction coupled with unified constant subtraction (RS-UCS), constant center (CC) and constant extraction (CE). The technique was introduced for the analysis of two pharmaceutical formulations used to treat cardiovascular diseases. The formulations are binary combinations of Amlodipine (AML) with either Atorvastatin (ATR) or Candesartan (CND) which shows interefernce absorbance signals. The technique was valid over the linearity range of (5.0-35.0 µg/ml) for AML, ATR and CND with recovery percentage 100.40 ± 1.88 , 100.00 ± 0.86 and 99.83 ± 1.07, respectively . The extracted signals were tested for its purity by spectral contrast angle (cos θ) to illustrate the efficency of the HIAM technique where cos θ values ranges from (0.9902 to 0.9986). The presented technique was fully validated regarding ICH guidelines and were statistically compared using one-way ANOVA at 95% confidence.

Determination of candesartan or olmesartan in hypertensive patient plasma using UPLC-MS/MS

Candesartan and olmesartan are angiotensin II receptor blockers (ARBs) used for the treatment of hypertension and heart failure. Quantitation methods for candesartan and olmesartan were developed using ultra-high performance liquid chromatography-tandem mass spectrometry following protein precipitation. Candesartan was separated using 5 mM ammonium formate (A) and 100% acetonitrile (B) and olmesartan was separated using 2 mM ammonium formate with 0.1% formic acid (A) and 100% acetonitrile (B). Separation was performed using an isocratic method with a Thermo hypersil GOLD C18 column. Electrospray ionization was used for analyte ionization and detection of candesartan, olmesartan, and the internal standards by multiple reaction monitoring. Developed method showed excellent linearity (r > 0.99) in the concentration range of 2-500 ng/mL for candesartan and 5-2,500 ng/mL for olmesartan. Accuracies were 86.70-108.8% for candesartan and 87.87-112.6% for olmesartan. These methods were able to successfully measure plasma candesartan or olmesartan concentrations in hypertensive patients. This study can be used for pharmacokinetic studies of candesartan or olmesartan in humans.

Low-dose candesartan prevents schizophrenia-like behavioral alterations in a neurodevelopmental two-hit model of schizophrenia

Schizophrenia is a severe mental disorder with complex etiopathogenesis. Based on its neurodevelopmental features, an animal model induced by "two-hit" based on perinatal immune activation followed by peripubertal unpredictable stress was proposed. Sex influences the immune response, and concerning schizophrenia, it impacts the age of onset and symptoms severity. The neurobiological mechanisms underlying the influence of sex in schizophrenia is poorly understood. Our study aimed to evaluate sex influence on proinflammatory and oxidant alterations in male and female mice exposed to the two-hit model of schizophrenia, and its prevention by candesartan, an angiotensin II type 1 receptor (AT1R) blocker with neuroprotective properties. The two-hit model induced schizophrenia-like behavioral changes in animals of both sexes. Hippocampal microglial activation alongside the increased expression of NF-κB, and proinflammatory cytokines, namely interleukin (IL)-1β and TNF-α, were observed in male animals. Conversely, females presented increased hippocampal and plasma levels of nitrite and plasma lipid peroxidation. Peripubertal administration of low-dose candesartan (0.3 mg/kg PO) prevented behavioral, hippocampal, and systemic changes in male and female mice. While these results indicate the influence of sex on inflammatory and oxidative changes induced by the two-hit model, candesartan was effective in both males and females. The present study advances the neurobiological mechanisms underlying sex influence in schizophrenia and opens new avenues to prevent this devasting mental disorder.

Candesartan protects against d-galactose induced - Neurotoxicity and memory deficit via modulation of autophagy and oxidative stress

PURPOSE

d-galactose induces neuroinflammation and memory deficit via oxidative stress. Candesartan is an angiotensin II-receptor blocker and has proved neuroprotective properties. This study aimed to investigate the neuroprotective effect of candesartan against d-galactose induced neuroinflammation and memory deficit via autophagy.

METHODS

Twenty-eight male Wistar rats aged 3 months were divided into four equal groups: control (vehicle), d-gal (100 mg/kg d-galactose), cand (1 mg/kg candesartan), and cand+d-gal (100 mg/kg d-galactose & 1 mg/kg candesartan). All treatments were given orally and daily for 4 weeks. Assessment of memory was done using Morris water maze (MWM) test. Brain tissue was assessed for malondialdehyde (MDA), total thiol, catalase activity, glial fibrillary acidic protein (GFAP) and gene expression of TNF-α, GDNF-1 as well as autophagy genes (Beclin 1 and ATG 5).

RESULTS

Prophylactic treatment of candesartan in d-galactose-treated rats significantly (p < 0.001) reduced oxidative stress via reduction of MDA as well as elevation of catalase activity and total thiol levels. Additionally, candesartan prophylactic treatment significantly increased gene expression of GDNF-1 and decreased gene expression of TNF-α. Furthermore, candesartan significantly increased the expression of autophagy related gene (Beclin 1 and ATG 5) in cand+d-gal treated rats. These results were supported by the histopathological findings which showed that candesartan prevented the neuronal injury in the cerebral cortex and hippocampus and decreased GFAP positive cells of the d-galactose-treated rats. Moreover, MWM test showed that candesartan significantly improved memory deficit in cand+d-gal treated rats.

CONCLUSION

Candesartan prevents d-galactose-induced neurotoxicity and memory deficit via activating autophagy and decreasing oxidative stress. Therefore, candesartan was a good candidate for age-related neurodegenerative disorders and memory deficit.

Physiologically based pharmacokinetic modeling of candesartan related to CYP2C9 genetic polymorphism in adult and pediatric patients

Candesartan cilexetil is an angiotensin II receptor blocker and it is widely used to treat hypertension and heart failure. This drug is a prodrug that rapidly converts to candesartan after oral administration. Candesartan is metabolized by cytochrome P450 2C9 (CYP2C9) enzyme or uridine diphosphate glucurinosyltransferase 1A3, or excreted in an unchanged form through urine, biliary tract and feces. We investigated the effect of genetic polymorphism of CYP2C9 enzyme on drug pharmacokinetics using physiologically based pharmacokinetic (PBPK) modeling. In addition, by introducing the age and ethnicity into the model, we developed a model that can propose an appropriate dosage regimen taking into account the individual characteristics of each patient. To evaluate the suitability of the model, the results of a clinical trial on twenty-two healthy Korean subjects and their CYP2C9 genetic polymorphism data was applied. In this study, PK-Sim® was used to develop the PBPK model of candesartan.

The promising anti-virulence activity of candesartan, domperidone, and miconazole on Staphylococcus aureus

Staphylococcus aureus is a primary cause of hospital and community-acquired infections. With the emergence of multidrug-resistant S. aureus strains, there is a need for new drugs discovery. Due to the poor supply of new antimicrobials, targeting virulence of S. aureus may generate weaker selection for resistant strains, anti-virulence agents disarm the pathogen instead of killing it. In this study, the ability of the FDA-approved drugs domperidone, candesartan, and miconazole as inhibitors of S. aureus virulence was investigated. The effect of tested drugs was evaluated against biofilm formation, lipase, protease, hemolysin, and staphyloxanthin production by using phenotypic and genotypic methods. At sub-inhibitory concentrations, candesartan, domperidone, and miconazole showed a significant inhibition of hemolysin (75.8-96%), staphyloxanthin (81.2-85%), lipase (50-65%), protease (40-64%), and biofilm formation (71.4-90%). Domperidone and candesartan have similar activity and were more powerful than miconazole against S. aureus virulence. The hemolysins and lipase inhibition were the greatest under the domperidone effect. Candesartan showed a remarkable reduction in staphyloxanthin production. The highest inhibitory effect of proteolytic activity was obtained with domperidone and candesartan. Biofilm was significantly reduced by miconazole. Expression levels of crtM, sigB, sarA, agrA, hla, fnbA, and icaA genes were significantly reduced under candesartan (68.98-82.7%), domperidone (62.6-77.2%), and miconazole (32.96-52.6%) at sub-MIC concentrations. Candesartan showed the highest inhibition activity against crtM, sigB, sarA, agrA, hla, and icaA expression followed by domperidone then miconazole. Domperidone showed the highest downregulation activity against fnbA gene. In conclusion, candesartan, domperidone, and miconazole could serve as anti-virulence agents for attenuation of S. aureus pathogenicity.

Candesartan as a tentative treatment for COVID-19: A prospective non-randomized open-label study

BACKGROUND

This study aimed to investigate whether the addition of candesartan to the standard care regimen improved the outcome in patients with coronavirus 2019 (COVID-19).

METHODS

A prospective non-randomized open-label study was undertaken from May to August 2020 on 75 subjects (aged 18-70 years) hospitalized in Siloam Kelapa Dua Hospital. Uni- and multi-variable Cox regression analyses were performed to obtain hazard ratios (HRs). The primary outcomes were: (1) length of hospital stay; (2) time to negative swab; and (3) radiological outcome (time to improvement on chest X ray).

RESULTS

None of the 75 patients with COVID-19 required intensive care. All patients were angiotensin-receptor-blocker naïve. In comparison with the control group, the candesartan group had a significantly shorter hospital stay [adjusted HR 2.47, 95% confidence interval (CI) 1.16-5.29] after adjusting for a wide range of confounders, and no increased risk of intensive care. In the non-obese subgroup, the candesartan group had a shorter time to negative swab (unadjusted HR 2.11, 95% CI 1.02-4.36; adjusted HR 2.40, 95% CI 1.08-5.09) and shorter time to improvement in chest x ray (adjusted HR 2.82, 95% CI 1.13-7.03) compared with the control group.

CONCLUSION

Candesartan significantly reduces the length of hospital stay after adjustment for covariates. All primary outcomes improved significantly in the non-obese subgroup receiving candesartan.

CoQ10 augments candesartan protective effect against tourniquet-induced hind limb ischemia-reperfusion: Involvement of non-classical RAS and ROS pathways

Tourniquet is a well-established model of hind limb ischemia–reperfusion (HLI/R) in rats. Nevertheless, measures should be taken to alleviate the expected injury from ischemia/ reperfusion (I/R). In the present study, 30 adult male Sprague-Dawley rats were randomly divided into 5 groups (n = 6): control, HLI/R, HLI/R given candesartan (1 mg/kg, P.O); HLI/R given Coenzyme Q10 (CoQ10) (10 mg/kg, P.O); HLI/R given candesartan (0.5 mg/kg) and CoQ10 (5 mg/kg). The drugs were administered for 7 days starting one hour after reperfusion. Candesartan and CoQ10 as well as their combination suppressed gastrocnemius content of angiotensin II while they raised angiotensin-converting enzyme 2 (ACE2) activity, angiotensin (1–7) expression, and Mas receptor mRNA level. Consequently, candesartan and/or CoQ10 reversed the oxidative stress and inflammatory changes that occurred following HLI/R as demonstrated by the rise of SOD activity and the decline of MDA, TNF-α, and IL-6 skeletal muscle content. Additionally, candesartan and/or CoQ10 diminished gastrocnemius active caspase-3 level and phospho-p38 MAPK protein expression. Our study proved that CoQ10 enhanced the beneficial effect of candesartan in a model of tourniquet-induced HLI/R by affecting classical and non-classical renin-angiotensin system (RAS) pathway. To our knowledge, this is the first study showing the impact of CoQ10 on skeletal muscle RAS in rats.

Inhibition of angiotensin II type 1 receptor by candesartan reduces tumor growth and ameliorates fibrosis in colorectal cancer

Colorectal cancer (CRC) is an important cause of cancer-related mortality. Aberrant activation of the renin-angiotensin system (RAS) is reported to be associated with poor clinical outcomes in patients with CRC. This study was designed to explore the anti-tumor effects of the angiotensin receptor blocker Candesartan either alone or in combination with 5-FU in in vitro and in vivo models of CRC. The cytotoxic effects of Candesartan were assessed using the MTT assay in two colorectal cancer cell lines (CT-26 and SW-480). To investigate the potential regulatory role of Candesartan on tumor growth, apoptosis, and migration, the expression levels of Cyclin D1, Survivin, MMP3, MMP9, and E-cadherin mRNAs were evaluated. The oxidant/antioxidant balance was also examined by determining the levels of MDA, thiols, SOD, and CAT. We used a xenograft model of colon cancer to investigate the effects of Candesartan alone, or in combination with 5-FU, on tumor growth following histological staining (Hematoxylin & Eosin and Masson trichrome staining) and biochemical studies as well as gene expression analyses by RT-PCR and western blotting. Candesartan suppressed tumor cell proliferation and migration by modulating Cyclin D1, MMP3/9, and E-cadherin. Treatment with Candesartan either alone, or in combination with 5-FU decreased tumor size in the mouse model, and also increased the level of oxidative markers MDA and reduced CAT, SOD, and thiols. Histological evaluation showed that Candesartan increased tumor necrosis, reduced tumor density and attenuated collagen deposition reducing tumor fibrosis in tumor xenograft. Candesartan, an inhibitor of the RAS, when used in combination with 5-FU reduced tumor growth by inhibiting fibrosis and inducing ROS production, supporting further clinical studies on this therapeutic approach for treatment of CRC.

Stronger Effect of Azilsartan on Reduction of Proteinuria Compared to Candesartan in Patients with CKD: A Randomized Crossover Trial

INTRODUCTION

Angiotensin receptor blockers (ARBs) are preferably used in hypertensive patients with CKD. Azilsartan is a strong antihypertensive ARB, but its antiproteinuric effects are not well understood. We compared the antiproteinuric effect of azilsartan and candesartan in CKD patients in an open-label, randomized, crossover trial.

METHODS

A total of 111 patients were treated with 20 mg of azilsartan daily for 2 months as a run-in period. After the run-in period, patients were randomized into 2 arms and received either 20 mg of azilsartan or 8 mg of candesartan daily for 3 months in a crossover trial. The primary outcome was the percent change in urinary protein-to-Cr ratio (UPCR).

RESULTS

Ninety-five patients completed the trial. The mean age was 64.3 years. The estimated glomerular filtration rate (eGFR) and UPCR were 41.5 mL/min/1.73 m2 and 1.8 g/gCr, respectively. The baseline systolic and diastolic blood pressures were 131.4 and 71.0 mm Hg, respectively. The mean percent change in the UPCR was -3.8% in the azilsartan group and 30.8% in the candesartan group at the 1st endpoint (p = 0.0004), and 6.1% in the azilsartan group and 25.8% in the candesartan group at the 2nd (final) endpoint (p = 0.029). The incidence of adverse events, including eGFR levels and serum potassium levels, was not significantly different between the groups.

CONCLUSION

A 20 mg azilsartan dose had potent antiproteinuric effects compared with an 8 mg candesartan dose, without an increase in adverse events. Azilsartan may provide renal protection in addition to antihypertensive effects in CKD patients.

Study of Neuroprotection by a Combination of the Biological Antioxidant (Eucalyptus Extract) and the Antihypertensive Drug Candesartan against Chronic Cerebral Ischemia in Rats

Chronic cerebral ischemia with a notable long-term cessation of blood supply to the brain tissues leads to sensorimotor defects and short- and long-term memory problems. Neuroprotective agents are used in an attempt to save ischemic neurons from necrosis and apoptosis, such as the antioxidant agent Eucalyptus. Numerous studies have demonstrated the involvement of the renin-angiotensin system in the initiation and progression of cardiovascular and neurodegenerative diseases. Candesartan is a drug that acts as an angiotensin II receptor 1 blocker. We established a rat model exhibiting sensorimotor and cognitive impairments due to chronic cerebral ischemia induced by the ligation of the right common carotid artery. Wistar male rats were randomly divided into five groups: Sham group, Untreated Ligated group, Ischemic group treated with Eucalyptus (500 mg/kg), Ischemic group treated with Candesartan (0.5 mg/kg), and Ischemic group treated with a combination of Eucalyptus and Candesartan. To evaluate the sensorimotor disorders, we performed the beam balance test, the beam walking test, and the modified sticky test. Moreover, the object recognition test and the Morris water maze test were performed to assess the memory disorders of the rats. The infarct rat brain regions were subsequently stained using the triphenyltetrazolium chloride staining technique. The rats in the Sham group had normal sensorimotor and cognitive functions without the appearance of microscopic ischemic brain lesions. In parallel, the untreated Ischemic group showed severe impaired neurological functions with the presence of considerable brain infarctions. The treatment of the Ischemic group with a combination of both Eucalyptus and Candesartan was more efficient in improving the sensorimotor and cognitive deficits (p < 0.001) than the treatment with Eucalyptus or Candesartan alone (p < 0.05), by the comparison to the non-treated Ischemic group. Our study shows that the combination of Eucalyptus and Candesartan could decrease ischemic brain injury and improve neurological outcomes.

Design and optimization of candesartan loaded self-nanoemulsifying drug delivery system for improving its dissolution rate and pharmacodynamic potential

During the last decades, much attention has been focused on SNEDDS approach to resolve concerns of BCS II class drugs with accentuation on upgrading the solubility and bioavailability. The present hypothesis confirms the theory that SNEDDS can reduce the impact of food on Candesartan solubilization, thereby offering the potential for improved oral delivery without co-administration with meals. The present studies describe quality-by-design-based development and characterization of Candesartan loaded SNEDDS for improving its pharmacodynamic potential. D-optimal mixture design was used for systematic optimization of SNEDDS, which showed globule size of 13.91 nm, more rapid drug release rate of >90% in 30 min and 16 s for self-emulsification. The optimized formulations were extensively evaluated, where an in vitro drug release study indicated up to 1.99- and 1.10-fold enhancement in dissolution rate from SNEDDS over pure drug and marketed tablet. In vivo pharmacodynamic investigation also showed superior antihypertensive potential of SNEDDS in normalizing serum lipid levels as compared to pure drug and marketed tablet that was executed on male Wistar rats. Overall, this paper reports successful systematic development of candesartan-loaded SNEDDS with distinctly improved biopharmaceutical performance. This research work interpreted a major role of SNEDDS for enhancing the rate of dissolution and bioavailability of poorly water soluble drugs.

Pathophysiology and therapeutic relevance of PI3K(p110α) protein in atrial fibrillation: A non-interventional molecular therapy strategy

Genetically modified animal studies have revealed specific expression patterns and unequivocal roles of class I PI3K isoenzymes. PI3K(p110α), a catalytic subunit of class I PI3Ks is ubiquitously expressed and is well characterised in the cardiovascular system. Given that genetic inhibition of PI3K(p110α) causes lethal phenotype embryonically, the catalytic subunit is critically important in housekeeping and biological processes. A growing number of studies underpin crucial roles of PI3K(p110α) in cell survival, proliferation, hypertrophy and arrhythmogenesis. While the studies provide great insights, the precise mechanisms involved in PI3K(p110α) hypofunction and atrial fibrillation (AF) are not fully known. AF is a well recognised clinical problem with significant management limitations. In this translational review, we attempted a narration of PI3K(p110α) hypofunction in the molecular basis of AF pathophysiology. We sought to cautiously highlight the relevance of this molecule in the therapeutic approaches for AF management per se (i.e without conditions associate with cell proliferation, like cancer), and in mitigating effects of clinical risk factors in atrial substrate formation leading to AF progression. We also considered PI3K(p110α) in AF gene association, with the aim of identifying mechanistic links between the ever increasingly well-defined genetic loci (regions and genes) and AF. Such mechanisms will aid in identifying new drug targets for arrhythmogenic substrate and AF.

Interplay of cholesterol, membrane bilayers and the AT1R: A cholesterol consensus motif on AT1R is revealed

Hypertension, mediated by the Angiotensin II receptor type 1 (AT1R), is still the major cause of premature death despite the discovery of novel therapeutics, highlighting the importance of an in depth understanding of the drug-AT1R recognition mechanisms coupled with the impact of the membrane environment on the interaction of drugs with AT1R. Herein, we examine the interplay of cholesterol-lipid-candesartan and the AT1R using Molecular Dynamics simulations of a model membrane consisting of 60:40 mol%. DPPC:cholesterol, candesartan and the AT1R, mimicking the physiological cholesterol concentration in sarcolemma membranes. The simulations of the model membrane of 60:40 mol%. DPPC:cholesterol were further validated using DOSY NMR experiments. Interestingly, our results suggest a significant role of cholesterol in the AT1R function imposed through a Cholesterol Consensus Motif (CCM) in the receptor, which could be crucial in the drug binding process. Candesartan diffusion towards AT1R through incorporation into lipid bilayers, appears to be retarded by the presence of cholesterol. However, its direct approach towards AT1R may be facilitated through the mobility induced on the N-terminus by the cholesterol binding on the CCM these novel insights could pave the way towards the development of more potent pharmaceutical agents to combat hypertension more effectively.

The PARAGON-HF trial: the sacubitril/valsartan in heart failure with preserved ejection fraction

Heart failure (HF) with preserved ejection fraction (HFpEF) is a clinical condition characterized by large pathophysiology heterogeneity with lack of effective therapies as proven by the disappointing results generated by randomized controlled trials. The innovative therapeutic concept provided by sacubitril-valsartan, a molecule combining angiotensin receptor blocking agent and neprilysin inhibitor has suggested the hypothesis it would have led to a reduced risk of hospitalization for HF or death from cardiovascular causes among patients with HF and preserved ejection fraction. The PARAGON-HF (ClinicalTrials.gov number, NCT01920711) investigated HF subjects class II to IV HF, ejection fraction of 45% or higher, elevated level of natriuretic peptides, and structural heart disease to receive sacubitril-valsartan (target dose, 97 mg of sacubitril with 103 mg of valsartan twice daily) or valsartan (target dose, 160 mg twice daily). The trial missed the primary outcome of cardiovascular death and HF hospitalization (HFH) in the overall study population. A subgroup analysis addressed significant decrease of HFH in subjects with left ventricular ejection fraction below the median 57% value in the study. The data were consistent with previous post hoc analysis performed in studies where candesartan and spironolactone were investigated in HFpEF. Those results open the door to investigate angiotensin aldosterone and peptidases inhibition efficacy in the unexplored HF middle range ejection fraction, currently lacking of valid evidence.

[Standard headache and neuralgia treatments and SARS-CoV-2: opinion of the Spanish Society of Neurology's Headache Study Group]

Introduction

In recent months, doubts have arisen among patients, general practitioners, and neurologists as to whether some drugs commonly used in patients with headaches and neuralgia may favour or complicate the disease caused by SARS-CoV-2.

Material and methods

We collected information on the opinions of scientific societies and medicines agencies (American, European, and Spanish) to clarify doubts regarding the use of drugs such as lisinopril, candesartan, ibuprofen, corticosteroids, carbamazepine, and monoclonal antibodies targeting the calcitonin gene-related peptide in the context of the COVID-19 pandemic.

Results

We make recommendations about the use of standard headache treatments in the context of the COVID-19 pandemic, based on the current scientific evidence.

Conclusions

At present, there is no robust scientific argument to formally contraindicate any of the standard treatments employed for headaches and neuralgias.

Study of Candesartan Cilexetil: 2-Hydroxypropyl-β-Cyclodextrin Interactions: A Computational Approach Using Steered Molecular Dynamics Simulations

Cyclodextrins (CDs) are widely used in the pharmaceutical industry as transporters of lipophilic drugs due to their amphiphilic nature. The detailed study of the molecular interactions of drug complexes with CDs is very important in designing the best formulation for the transportation of lipophilic drugs. The drug: CD binding should be strong enough so that the complex is stable in the aquatic environment of the extracellular fluids, but also not very strong in order for the drug to be capable for being released in the proximity of the target receptor. In a recent study, we investigated the ΔG of binding between the commercially available, nontoxic 2-hydroxypropyl-β-cyclodextrin (2-HP-B-CD) and the antihypertensive drug candesartan cilexetil (CC), with the use of steered (or biased) molecular dynamics (sMD) and umbrella sampling method. This chapter describes comprehensively how to perform sMD and umbrella sampling in order to calculate the ΔG_binding of CC to the 2-HP-B-CD.

Protective Effects of Statin and Angiotensin Receptor Blocker in a Rat Model of Doxorubicin- and Trastuzumab-Induced Cardiomyopathy

BACKGROUND

Chemotherapy has led to improved survival in patients with breast cancer; however, it is associated with an increased risk of cardiac dysfunction and heart failure. We investigated the protective effects of rosuvastatin and candesartan, alone and in combination, in a doxorubicin- and trastuzumab-induced rat model of cardiomyopathy.

METHODS

Forty-two rats were allocated into six groups (G1-G6): G1, control; G2, doxorubicin only; G3, doxorubicin + trastuzumab; G4, doxorubicin + trastuzumab + rosuvastatin; G5, doxorubicin + trastuzumab + candesartan; and G6, doxorubicin + trastuzumab + rosuvastatin + candesartan. Doxorubicin and trastuzumab were sequentially administered for 28 days. Left ventricular end-systolic dimension and longitudinal strain (LS) were assessed via echocardiography. Left ventricular (LV) performance was evaluated using a microcatheter in the LV apex on day 28. Blood for biomarker analysis was collected from the inferior vena cava before sacrifice.

RESULTS

Doxorubicin in combination with trastuzumab increased the LV end-systolic dimension but worsened LS compared with the control group (all P < .05). The level of C-reactive protein was lower in the rosuvastatin treatment group (P = .007) than in the controls but not in the candesartan treatment group. Both rosuvastatin and candesartan attenuated the increase in glutathione. Candesartan treatment improved +dP/dt (P = .011), whereas rosuvastatin did not. In the combination treatment group, the worsening of LS was significantly attenuated compared with that in either the rosuvastatin or candesartan group (all P < .05).

CONCLUSIONS

In a rat model of doxorubicin- and trastuzumab-induced cardiomyopathy, rosuvastatin alleviated systemic inflammation, while candesartan improved LV performance. Combination therapy with rosuvastatin and candesartan demonstrated additional preventive effects on myocardial strain. The protective mechanisms of rosuvastatin and candesartan appear to be different but complementary in chemotherapy-induced cardiomyopathy.

Pharmacokinetics and bioequivalence of fixed-dose combination of candesartan cilexetil/amlodipine besylate (16/10 mg) versus coadministration of individual formulations in healthy subjects

This study compared the pharmacokinetics of a fixed-dose combination (FDC) of candesartan (16 mg) and amlodipine (10 mg) versus coadministration of individual formulations to clarify the bioequivalence of the FDC. In this randomized, open-label, single-dose, 2-treatment, 2-way crossover study, healthy Korean volunteers received a single dose of candesartan (16 mg) with amlodipine (10 mg) as either an FDC or single agents concomitantly administered, with a 2-week washout period. Serial blood samples were collected up to 72 hours after dosing for each treatment period, and plasma concentrations of candesartan and amlodipine were measured using a validated liquid chromatography-tandem mass spectrometry method. A total of 39 subjects completed the study. The geometric mean ratios (GMRs) and 90% confidence intervals (CIs) for the area under the plasma concentration-time curve from time 0 to the last measurement (AUC_0-t) and the peak plasma concentration (C_max) for candesartan were 1.0182 (0.9562–1.0841) and 0.9492 (0.8726–1.0324), respectively. The GMR and 90% CI for the AUC_0-t and C_max for amlodipine were 1.0552 (1.0255–1.0857) and 1.0668 (1.0259–1.1094), respectively. In conclusion, the new FDC formulation of candesartan (16 mg) and amlodipine (10 mg) was bioequivalent to the concomitant administration of single agents. A single dose of candesartan/amlodipine as the FDC or as single agents was well tolerated.

Candesartan ameliorates vascular smooth muscle cell proliferation via regulating miR-301b/STAT3 axis

Excessive vascular smooth muscle cell (VSMC) proliferation contributes to vascular remodeling and stroke during hypertension. Blockade of Angiotensin (AngII) type 1 receptor (AT1R) is shown to effectively attenuate VSMC proliferation and vascular remodeling, while the mechanisms underlying these protective effects are unclear. Here, we investigated whether the amelioration of VSMC proliferation mediated by candesartan, an AT1R blocker, could be associated with miRNA regulation. Based on the published data in rat aortic smooth muscle cells (RASMCs), we discovered that candesartan specifically reversed the AngII-induced decrease of miR-301b level in RASMCs and human aortic smooth muscle cells (HASMCs). Knockdown of miR-301b abolished candesartan-mediated inhibition of HASMC proliferation via promoting cell cycle transition. Computational analysis showed that miR-301b targets at 3'UTR of STAT3. MiR-301b upregulation inhibited the luciferase activity and protein expression of STAT3, whereas miR-301b knockdown increased STAT3 luciferase activity and expression. Furthermore, downregulation of STAT3 markedly abrogated the effects of miR-301b inhibition on candesartan-mediated HASMC proliferation, invasion, and migration. Collectively, this study suggests that miR-301b may be a novel molecular target of candesartan and provides a new understanding for the mechanisms underlying the cardiovascular effects of candesartan.

Candesartan in migraine prevention: results from a retrospective real-world study

Randomized studies have reported a positive effect of candesartan, an angiotensin II receptor antagonist, in migraine prevention. The aim of our study was to explore patient subjective efficacy of candesartan in a real-world sample of migraine patients and try to identify predictors of candesartan response. We audited the clinical records of 253 patients who attended the King's College Hospital, London, from February 2015 to December 2017, looking specifically at their response to candesartan. Univariate and multivariate logistic regression models were used to identify predictors of headache benefit. Odds ratios (OR) with confidence intervals (CI) 95% were calculated. Eighty-one patients (chronic migraine, n = 68) were included in the final analysis. Thirty-eight patients reported a positive response to candesartan, while 43 patients did not have a meaningful therapeutic effect. The median dose of candesartan was 8 mg and the median treatment period was 6 months. In a univariate logistic regression model, the presence of daily headache was associated with reduced odds of headache benefit (OR 0.39, 95% CI 0.16-0.96, p = 0.04). In multivariate logistic regression model, younger age (OR 0.92, 95% CI 0.87-0.98, p = 0.006) and longer disease duration (OR 1.06, 95% CI 1.01-1.12, p = 0.03) were associated with a good response to candesartan, while the presence of daily headache was associated with reduced odds of headache benefit (OR 0.16, 95% CI 0.04-0.71, p = 0.01). Having failed up to nine preventives in patients did not predict a treatment failure with candesartan as well. Candesartan yields clinical benefits in difficult-to-treat migraine patients, irrespective of previous failed preventives.

Headache medication and the COVID-19 pandemic

The world is currently dominated by the Corona Virus Disease 2019 (COVID-19) pandemic. Besides the obvious concerns about limitation of virus spread and providing the best possible care to infected patients, a concomitant concern has now arisen in view of a putative link between the use of certain drugs, such as Renin-Angiotensin System (RAS) inhibitors and ibuprofen, and an increased risk for COVID-19 infection. We here discuss this concern in relation to headache treatment and conclude that, based on current evidence, there is no reason to abandon treatment of headache patients with RAS inhibitors or ibuprofen.

Quantitative bio-analysis of pitavastatin and candesartan in rat plasma by HPLC-UV: Assessment of pharmacokinetic drug-drug interaction

A novel, precise, accurate and rapid HPLC-UV method was developed, optimised and fully validated for simultaneous estimation of pitavastatin (PIT) and candesartan (CAN) in rat plasma using telmisartan as an internal standard. Following liquid-liquid extraction of the analytes from plasma, chromatographic separation was accomplished on a Waters Reliant C18 column (4.6 × 250 mm, 5 µm) using ACN-5 mM Sodium acetate buffer (80:20, v/v; pH adjusted to 3.5 with acetic acid) as mobile phase at a flow rate of 0.8 mL/min and wavelength of 234 nm. The calibration curves were linear over the concentration ranges of 2-400 ng/mL and 3-400 ng/mL for pitavastatin and candesartan respectively. The method when validated as per US-FDA guidelines was found to be precise as well as accurate. Extraction recovery observed for both analytes was above 90% as well as reproducible and consistent. Stability studies showed the samples to be stable over a long period covering from sample collection to final analysis. The method was successfully applied to investigate pharmacokinetic interaction between PIT and CAN in wistar rats. The mean plasma concentration-time curves of PIT and CAN showed that single PIT as well as CAN show similar pharmacokinetic properties to those obtained when co-administrated with each other (P value >0.05). Hence, there is no evidence for a potential drug-drug interaction between PIT and CAN. This information provides evidence for clinical rational use of CAN and PIT in cardiovascular patients.

Exploring the role of the membrane bilayer in the recognition of candesartan by its GPCR AT1 receptor

Cardiovascular diseases and hypertension in particular are major health risks worldwide and the improvement on their treatment will be beneficial for the human health. AT1R antagonists belong to the sartans family that targets the renin-angiotensin aldosterone system (RAAS) through blocking the hormone angiotensin II to exert its detrimental effects in pathological states. As a consequence, they are beneficial to treat hypertension, diabetes related kidney failure and hyperaemic episodes. Long unbiased Molecular Dynamics (MD) simulations are performed in order to explore candesartan's possible 2D and 3D diffusion mechanisms towards AT1R receptor. 3D diffusion mechanism is referred to the direct binding of the AT1 antagonist candesartan to the AT1R 3D structure (PDB ID: 4YAY). 2D diffusion mechanism involves first, the incorporation of candesartan in the bilayer core and then its localization on the AT1R binding cavity, through a diffusion mechanism. The obtained results indicate that membranes interact significantly with the neutral form of candesartan, which is indeed approaching the receptors' active site through diffusion via the lipids. On the other hand, the deprotonated form of the drug is interacting with AT1R's extracellular loop and fails to enter the membrane, pointing out the importance of the pH microenvironment around the receptor. To validate the calculated diffusion coefficients of the drug in the lipid bilayers 2D DOSY NMR experiments were recorded and they were in good agreement. Information on the impact that has the interaction of candesartan with the membrane is very important for the rationally design and development of potent ARBs. Thus, its conformational features as well as its localization in the membrane core have to be thoroughly explored.

Cost Effectiveness Analysis of Candesartan Therapy in Comparison to Candesartan-Amlodipine Therapy on Hypertensive Outpatients

BACKGROUND:

he achievement of optimal hypertension therapy requires cost-effective medicine. The treatment of hypertensive patients needs for long-term medication have made medical costs a prime issue in health economics.

AIM:

This study aims to determine the cost effectiveness of candesartan therapy compared to candesartan-amlodipine therapy on hypertensive outpatients.

METHODS:

This is a prospective cohort study that compares candesartan therapy to candesartan-amlodipine therapy at a public hospital from payers’ perspective. The outcome is the percentage of targeted blood pressure decrease after three months of therapy. The cost effectiveness analysis uses the Incremental Cost Effectiveness Ratio (ICER) based on the ratio of cost difference to the outcome in both therapy groups.

RESULTS:

As many as 111 patients participated in this research, comprising 40 candesartan therapy patients and 71 patients with the combination of candesartan-amlodipine. Of the participants, 63.96% were female, 57.66% were aged 60 or older, and 56.32% had diabetes mellitus as the most common complication. Results show that the average direct medical cost per patient for a therapy of three months with candesartan was IDR 1,050,536 ± 730,007 and IDR 760,040 ± 614,290 for a candesartan-amlodipine therapy. The mean decline of systolic and diastolic blood pressure under candesartan therapy is less than that of candesartan-amlodipine, although without any significant difference (p > 0.05). It follows that the effectiveness of candesartan (85%) is greater than that of the candesartan-amlodipine combination (84.50%). Candesartan therapy is thereby more cost-effective with an ICER value of IDR 580,993/%.

CONCLUSION:

Hypertension therapy by candesartan is more cost-effective than candesartan-amlodipine therapy with a cost addition of IDR 580,993.

Preparation, characterization and ex vivo-in vivo assessment of candesartan cilexetil nanocrystals via solid dispersion technique using an alkaline esterase activator carrier

The objective of this study was to improve candesartan cilexetil (CC) efficacy by formulating nanocrystals via solid dispersion (SD) technique using tromethamine (Tris). SD was prepared by solvent evaporation at different drug carrier ratios, evaluated for particle size, vitro dissolution studies, TEM, FTIR, and X-ray powder diffraction. Ex vivo, in vivo pharmacokinetic parameters were conducted on selected formulae compared to drug suspension and marketed product. Size analysis demonstrated formation of particles in the nanorange lower than 300 nm. A burst drug release followed by an improved dissolution was observed indicating instant formation of nanocrystals along with amorphization as confirmed by X-ray diffraction. FTIR studies suggested the absence of chemical interaction between Tris and CC. TEM revealed formation of irregular oval nanoparticles. SD-1:5 has higher apparent permeability coefficient compared to CC suspension. Furthermore, the pharmacokinetic results proved the ability of the formed nanoparticles to enhance the efficacy of CC compared to drug suspension and marketed product. In conclusion, using of Tris as alkaline esterase activator carrier could be a promising tool to bypass the controversial effect of esterase enzymes that may be a source for inter-individual variations affecting ester prodrug candidates' efficacy.

Suppressive effects of type I angiotensin receptor antagonists, candesartan and irbesartan on allergic asthma

The effects of candesartan and irbesartan, antagonists of the type I angiotensin II receptor, were investigated on allergic asthma. The antigen-induced degranulation was measured by evaluating β-hexosaminidase activity in vitro. Additionally, a murine ovalbumin-induced allergic asthma model was used to test the in vivo efficacy. It was observed that while candesartan inhibited the antigen-induced degranulation in rat RBL-2H3 mast cells, irbesartan did not. Administration of candesartan and irbesartan decreased the number of immune cells in the bronchoalveolar lavage fluid and reduced the expression of Th2 (IL-4, IL-5, and IL-13) and Th1 cytokines (IL-2 and IFN-γ) in the lung tissues of mice with ovalbumin-induced allergic asthma. Histological studies revealed that both antagonists reduced inflammation and mucin production in the lungs. Therefore, these findings provide evidence that candesartan and irbesartan could have potential applications as anti-allergic agents.

Dataset on significant role of Candesartan on cognitive functions in rats having memory impairment induced by electromagnetic waves

Rapid growing of mobile phones users has raised about the possible effects of these electromagnetic waves (EMW) on human health. Many studies have examined the role of these EMW on biological systems, but the results are still contradictory and controversial. In addition to EMW, over-activation of angiotensin type 1 receptor (AT1R) has been associated with cognitive decline, incidence and progression of neurodegenerative diseases. Candesartan, an AT1R blocker, is well recognized for treatment of hypertension. However, its role on cognitive functions such as spatial and recognition memory remains elusive. Thus, young rats were divided into 3 groups: control, exposed to radiofrequency electromagnetic waves (EMW), and exposed to EMW during Candesartan treatment (EMW+Cand). Spatial memory performance was assessed using the object recognition test and recognition memory performance using Morris water maze test. Significant differences where found between EMW exposed rats and EMW+Cand exposed rats treated with Candesartan compared to control, EMW group impaired learning, spatial and short term memory along with unaffected sensorimotor function whereas EMW+Cand group improved learning, spatial memory and short term memory deficit induced by EMW in addition to absence of its role on sensorimotor function. Although our data provides evidences of the protective role of Candesartan against EMW-induced cognitive decline, more future studies are still needed to confirm these findings which can provide new fields in treatment of EMW-induced damage by Candesartan.

Angiotensin Type 1 Receptor Antagonists Protect Against Alpha-Synuclein-Induced Neuroinflammation and Dopaminergic Neuron Death

The loss of dopaminergic neurons and α-synuclein accumulation are major hallmarks of Parkinson's disease (PD), and it has been suggested that a major mechanism of α-synuclein toxicity is microglial activation. The lack of animal models that properly reproduce PD, and particularly the underlying synucleinopathy, has hampered the clarification of PD mechanisms and the development of effective therapies. Here, we used neurospecific adeno-associated viral vectors serotype 9 coding for either the wild-type or mutated forms of human alpha-synuclein (WT and SynA53T, respectively) under the control of a synapsin promoter to further induce a marked dopaminergic neuron loss together with an important microglial neuroinflammatory response. Overexpression of neuronal alpha-synuclein led to increased expression of angiotensin type 1 receptors and NADPH oxidase activity, together with a marked increase in the number of OX-6-positive microglial cells and expression of markers of phagocytic activity (CD68) and classical pro-inflammatory/M1 microglial phenotype markers such as inducible nitric oxide synthase, tumor necrosis factor alpha, interleukin-1β, and IL-6. Moreover, a significant decrease in the expression of markers of immunoregulatory/M2 microglial phenotype such as the enzyme arginase-1 was constantly observed. Interestingly, alpha-synuclein-induced changes in microglial phenotype markers and dopaminergic neuron death were inhibited by simultaneous treatment with the angiotensin type 1 blockers candesartan or telmisartan. Our results suggest the repurposing of candesartan and telmisartan as a neuroprotective strategy for PD.

Silencing VEGF-B Diminishes the Neuroprotective Effect of Candesartan Treatment After Experimental Focal Cerebral Ischemia

The pro-survival effect of VEGF-B has been documented in different in vivo and in vitro models. We have previously shown an enhanced VEGF-B expression in response to candesartan treatment after focal cerebral ischemia. In this study, we aimed to silence VEGF-B expression to assess its contribution to candesartan's benefit on stroke outcome. Silencing VEGF-B expression was achieved by bilateral intracerebroventricular injections of lentiviral particles containing short hairpin RNA (shRNA) against VEGF-B. Two weeks after lentiviral injections, rats were subjected to either 90 min or 3 h of middle cerebral artery occlusion (MCAO) and randomized to intravenous candesartan (1 mg/kg) or saline at reperfusion. Animals were sacrificed at 24 or 72 h and brains were collected and analyzed for hemoglobin (Hb) excess and infarct size, respectively. Functional outcome at 24, 48 and 72 h was assessed blindly. Candesartan treatment improved neurobehavioral and motor function, and decreased infarct size and Hb. While silencing VEGF-B expression diminished candesartan's neuroprotective effect, candesartan-mediated vascular protection was maintained even in the absence of VEGF-B suggesting that this growth factor is not the mediator of candesartan's vascular protective effects. However, VEGF-B is a mediator of neuroprotection achieved by candesartan and represents a potential drug target to improve stroke outcome. Further studies are needed to elucidate the underlying molecular mechanisms of VEGF-B in neuroprotection and recovery after ischemic stroke.

In vitro analysis of drugs that improve hyperglycemia-induced blood-brain barrier dysfunction

BACKGROUND

Blood-brain barrier (BBB) disruptions are a key feature of hyperglycemia (HG)-induced cerebral damage. Patients with diabetes mellitus often have other cerebrovascular disease risk factors including hypertension, dyslipidemia, arrhythmia, and atherosclerosis obliterans. However, whether the drugs for these comorbidities are effective for improving HG-induced BBB damage is unclear.

METHODS

We investigated the effect of pitavastatin, candesartan, cilostazol, propranolol, and eicosapentaenoic acid on HG-induced BBB damage. In vitro BBB models consisting of primary cultures of rat brain capillary endothelial cells were subjected to HG (55 mM d-glucose).

RESULTS

We observed a significant decrease in transendothelial electrical resistance (TEER) with HG, showing that HG compromised the integrity of the in vitro BBB model. No significant decrease in cell viability was seen with HG, but HG increased the production of reactive oxygen species. Pitavastatin and candesartan inhibited decreases in TEER induced by HG.

CONCLUSIONS

In summary, pitavastatin and candesartan improved HG-induced BBB damage and this in vitro model of HG-induced BBB dysfunction contributes to the search for BBB protective drugs.

Antihypertensive drug-candesartan attenuates TRAIL resistance in human lung cancer via AMPK-mediated inhibition of autophagy flux

Angiotensin II type 1 receptor blockers (ARBs) are widely used as antihypertensive drugs. Candesartan is an ARB that has also been known for its anticancer effects but the exact molecular mechanism is remaining elusive. In this research, we showed for the first time that candesartan treatment significantly sensitized human lung adenocarcinoma cells to Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-mediated apoptosis by targeting TRAIL-DR5. TRAIL selectively kills cancer cells by binding to death receptors on the cell membrane, beyond the levels causing minimal toxicity in normal cells. However, some non-small-cell lung carcinoma (NSCLC) patients are resistant to TRAIL treatment in clinical trials due to inactivation of the death receptors during cytoprotective autophagy. The molecular mechanisms underlying candesartan-induced TRAIL-mediated apoptosis involved the downstream of AMPK phosphorylation resulting inhibition of autophagy flux, recruitment of death receptor 5 (DR5) and activation of apoptotic caspase cascade. Candesartan treatment also inhibits the expression of anti-apoptotic protein c-FLIP. Furthermore, blocking DR5 signaling using DR5 siRNA negatively regulated the apoptotic pathway and also induced autophagy flux, demonstrating the cytoprotective role of autophagy responsible for treatment resistance. This suggests that candesartan can be used to sensitize tumors to TRAIL treatment and may represent a useful strategy for human adenocarcinoma patients to overcome TRAIL resistance. Candesartan in combination with TRAIL also could be a novel therapeutic treatment for patients presenting both conditions of hypertension and lung cancer.

Inhibitory effects of candesartan on KCa3.1 potassium channel expression and cell culture and proliferation in peripheral blood CD4+T lymphocytes in Kazakh patients with hypertension from the Xinjiang region

BACKGROUND AND AIM

Increasing evidence confirms that potassium channels are essential for lymphocyte activation, suggesting an involvement in the development of hypertension. Moreover, chronic inflammation is regarded as a direct or indirect manifestation of hypertension, highlighting the theoretical mechanisms. In this study, we investigated changes in KCa3.1 potassium channel expression in the blood of hypertensive and healthy Kazakh people in north-west China.

METHODS

Flow cytometry technology was used for T-lymphocyte subtype analysis. Changes in the messenger RNA and protein expression of the KCa3.1 potassium channel in CD4⁺ T lymphocytes were detected using real-time quantitative polymerase chain reaction and western blots, using CD4⁺ T-cell samples from hypertensive Kazakh patients divided into candesartan and TRAM-34 treatment groups, and healthy case controls. Peripheral blood CD4⁺ T lymphocytes were activated and proliferated in vitro and then incubated for 0, 24, and 48 h under various treatment conditions. Changes in CD4⁺ T-lymphocytic proliferation were determined using Cell Counting Kit-8 and electron microscope photography.

RESULTS

Expression of KCa3.1 was significantly higher in the hypertensive patients than in the controls (p < 0.05). Compared with the healthy group, Kazakh hypertensive patients had a reduced proportion of CD4⁺ T lymphocytes (p < 0.05).Candesartan and TRAM-34 intervention for 24 h and 48 h inhibited the expression of Kv1.3 and KCa3.1 at mRNA and protein level (p < 0.05).

CONCLUSIONS

Increase in functional KCa3.1 channels expressed in CD4⁺ T lymphocytes of Kazakh patients with hypertension was blocked by candesartan, providing theoretical support for hypertension treatment at the cellular ion channel level. Candesartan may potentially regulate hypertensive inflammatory responses by inhibiting T-lymphocytic proliferation and KCa3.1 potassium channel expression in CD4 ⁺ T lymphocytes.

Noncholestatic acute hepatocellular injury following candesartan administration

Arterial hypertension is a highly manageable disorder due to a variety of drugs available for its treatment. Since the late 1990s, angiotensin II receptor blockers have been widely prescribed, achieving appropriate control in patients' blood pressure. Few cases of serious adverse effects have been reported to date. Here, we present a case of acute hepatocellular injury secondary to candesartan administration. Further studies should be performed in patients who present with this adverse effect, in order to prevent more serious outcomes.

Cell-based and pharmacological neurorestorative therapies for ischemic stroke

Ischemic stroke remains one of most common causes of death and disability worldwide. Stroke triggers a cascade of events leading to rapid neuronal damage and death. Neuroprotective agents that showed promise in preclinical experiments have failed to translate to the clinic. Even after decades of research, tPA remains the only FDA approved drug for stroke treatment. However, tPA is effective when administered 3-4.5 h after stroke onset and the vast majority of stroke patients do not receive tPA therapy. Therefore, there is a pressing need for novel therapies for ischemic stroke. Since stroke induces rapid cell damage and death, neuroprotective strategies that aim to salvage or replace injured brain tissue are challenged by treatment time frames. To overcome the barriers of neuroprotective therapies, there is an increasing focus on neurorestorative therapies for stroke. In this review article, we provide an update on neurorestorative treatments for stroke using cell therapy such as bone marrow derived mesenchymal stromal cells (BMSCs), human umbilical cord blood cells (HUCBCs) and select pharmacological approaches including Minocycline and Candesartan that have been employed in clinical trials. This review article discusses the present understanding of mechanisms of neurorestorative therapies and summarizes ongoing clinical trials. This article is part of the Special Issue entitled 'Cerebral Ischemia'.

Candesartan, angiotensin II type 1 receptor blocker is able to relieve age-related cognitive impairment

BACKGROUND

Candesartan is one of the standard antihypertensive drug belonging to AT1R angiotensin receptor blockers (ARBs) group. Beneficial effects of this drug in the treatment of hypertension are well recognized. In this study we tested a hypothesis that candesartan could alleviate age-related memory decline.

METHODS

Aged and young rats have been treated with candesartan (0.1mg kg^-1) for 21days and then underwent a battery of behavioral tests: for assessment of long-term memory (Passive avoidance test - PA), recognition memory (Object recognition test - OR), locomotor functions (Open field - OF) and anxiety behavior (Elevated plus maze - EPM).

RESULTS

Aged rats (2-years-old) displayed clear declining tendency in the retrieval of passive avoidance behavior showing thus increased forgetting. Prolonged administration of candesartan significantly (p<0.01) reversed this phenomenon causing recall measured as the avoidance latency, and surprisingly also showed the tendency to recall deterioration observed in the young rats. More optimistic results were achieved in the OR, where candesartan significantly improved recognition memory (p<0.001) of aged rats who performed even better than the young ones (p<0.05).

CONCLUSIONS

It appears that candesartan potently abolishes some kinds of aging-induced memory impairments and cognitive declines in aged rats, but in some circumstances it may even could increase the damage of memory. It seems that the use of sartans in the treatment of hypertension for patients with associated cognitive impairment, or for people in risk groups for such disorders can be an interesting alternative.