Chronic diarrhoea, weight loss and a positive anti-tissue transglutaminase antibody: A case report of olmesartan-induced enteropathy.

Olmesartan is an angiotensin II receptor blocker licensed for the treatment of hypertension. It can cause a sprue-like enteropathy (SLE), characterised by chronic diarrhoea, weight loss and villous atrophy. Transiently raised anti-tissue transglutaminase (ATTG) antibody has also been rarely reported in the literature.We describe the case of a woman in her mid-50s, who presented with a history of intermittent loose stools over 1 year, associated with significant weight loss. She had two marginally raised serum ATTG antibody tests during her work-up.After extensive investigations, she was diagnosed with olmesartan-induced enteropathy. On subsequent follow-up, her symptoms had resolved with cessation of her olmesartan therapy.This case adds to existing literature, highlighting the importance of considering olmesartan as a possible differential diagnosis for SLE. It also reports the presence of a raised ATTG antibody which is infrequently reported in this context.

Non-HLA angiotensin-type-1 receptor autoantibodies mediate the long-term loss of grafted neurons in Parkinson's disease models.

BACKGROUND: Clinical trials have provided evidence that transplants of dopaminergic precursors, which may be replaced by new in vitro stem cell sources, can integrate into the host tissue, and alleviate motor symptoms in Parkinson´s disease (PD). In some patients, deterioration of graft function occurred several months after observing a graft-derived functional improvement. Rejection of peripheral organs was initially related to HLA-specific antibodies. However, the role of non-HLA antibodies is now considered also relevant for rejection. Angiotensin-II type-1 receptor autoantibodies (AT1-AA) act as agonists of the AT1 receptors. AT1-AA are the non-HLA antibodies most widely associated with graft dysfunction or rejection after transplantation of different solid organs and hematopoietic stem cells. However, it is not known about the presence and possible functional effects of AT1-AA in dopaminergic grafts, and the effects of treatment with AT1 receptor blockers (ARBs) such as candesartan on graft survival. METHODS: In a 6-hydroxydopamine PD rat model, we studied the short-term (10 days)- and long-term (3 months) effects of chronic treatment with the ARB candesartan on survival of grafted dopaminergic neurons and microglial graft infiltration, as well as the effects of dopaminergic denervation and grafting on serum and CSF AT1-AA levels. The expression of AT1 receptors in grafted neurons was determined by laser capture microdissection. RESULTS: At the early period post-grafting, the number of grafted dopaminergic neurons that survived was not significantly different between treated and untreated hosts (i.e., control rats and rats treated with candesartan), probably because, just after grafting, other deleterious factors are predominant for dopaminergic cell death, such as mechanical trauma, lack of growth factors/nutrients and ischemia. However, several months post-grafting, we observed a significantly higher number of surviving dopaminergic neurons and a higher density of striatal dopaminergic terminals in the candesartan-treated group. For several months, grafted rats showed blood and cerebrospinal fluid levels of AT1-AA higher than normal controls, and also higher AT1-AA levels than non-grafted parkinsonian rats. CONCLUSIONS: The results suggest the use of ARBs such as candesartan in PD patients, particularly before and after dopaminergic grafts, and the need to monitor AT1-AA levels in PD patients, particularly in those candidates for dopaminergic grafting.

Investigation of Strategies to Block Downstream Effectors of AT1R-Mediated Signalling to Prevent Aneurysm Formation in Marfan Syndrome.

Cardiovascular outcome in Marfan syndrome (MFS) patients most prominently depends on aortic aneurysm progression with subsequent aortic dissection. Angiotensin II receptor blockers (ARBs) prevent aneurysm formation in MFS mouse models. In patients, ARBs only slow down aortic dilation. Downstream signalling from the angiotensin II type 1 receptor (AT1R) is mediated by G proteins and ß-arrestin recruitment. AT1R also interacts with the monocyte chemoattractant protein-1 (MCP-1) receptor, resulting in inflammation. In this study, we explore the targeting of ß-arrestin signalling in MFS mice by administering TRV027. Furthermore, because high doses of the ARB losartan, which has been proven beneficial in MFS, cannot be achieved in humans, we investigate a potential additive effect by combining lower concentrations of losartan (25 mg/kg/day and 5 mg/kg/day) with barbadin, a ß-arrestin blocker, and DMX20, a C-C chemokine receptor type 2 (CCR2) blocker. A high dose of losartan (50 mg/kg/day) slowed down aneurysm progression compared to untreated MFS mice (1.73 ± 0.12 vs. 1.96 ± 0.08 mm, p = 0.0033). TRV027, the combination of barbadin with losartan (25 mg/kg/day), and DMX-200 (90 mg/kg/day) with a low dose of losartan (5 mg/kg/day) did not show a significant beneficial effect. Our results confirm that while losartan effectively halts aneurysm formation in Fbn1C1041G/+ MFS mice, neither TRV027 alone nor any of the other compounds combined with lower doses of losartan demonstrate a notable impact on aneurysm advancement. It appears that complete blockade of AT1R function, achieved by administrating a high dosage of losartan, may be necessary for inhibiting aneurysm progression in MFS.

A Review of Olmesartan-based Therapy in Targeting Effective Blood Pressure Control and Achieving Blood Pressure Goals.

For >3 decades now, angiotensin receptor blockers (ARB) have been used in the management of hypertension (HTN) and HTN-related cardiovascular (CV) diseases. Olmesartan medoxomil (OLM) is an angiotensin II type 1 (AT1) receptor antagonist (or blocker) that binds tightly to the AT1 receptor with long-lasting efficacy over the 24-hour period and safety demonstrated in several trials. It is well tolerated and effective in reducing blood pressure (BP) in mono and combination therapy with thiazide diuretics or calcium channel blockers across a wide range of patient subgroups. The effectiveness and safety of OLM-based combination therapies have good and tolerable profiles with high adherence in the fixed single-pill formulation. Consistent antihypertensive efficacy and good tolerability when used as monotherapy or as a combined therapy make OLM a valuable treatment option for adults with HTN. In this review, we discuss the important clinical implications of OLM as an optimal choice as monotherapy and combination therapy in managing patients with HTN.

An immunochromatographic strip sensor for rapid and sensitive detection of candesartan, olmesartan medoxomil, and irbesartan in herbal beverages.

Sartans, as a class of antihypertensive drugs, pose a threat to human health when illegally added to herbal beverages. It is crucial to detect sartans in herbal beverages. We have developed a highly sensitive monoclonal antibody against candesartan (CAN), olmesartan medoxomil (OLM), and irbesartan (IRB), with 50% inhibitory concentrations (IC50) that were obtained via indirect enzyme-linked immunosorbent assay (ic-ELISA) as 0.178 ng mL-1, 0.185 ng mL-1, and 0.262 ng mL-1 against CAN, OLM, and IRB, respectively. Based on this monoclonal antibody, we developed a rapid screening method for CAN, OLM, and IRB in herbal beverage samples using an immunochromatographic assay (ICA) strip. Test for 15 minutes after simple and rapid sample pre-treatment and the results of this method can be obtained through naked eye observation. The detection limits (LODs) of the ICA strip for CAN, OLM, and IRB in herbal beverage samples are lower than 0.15 ng mL-1, and the results of the ICA strip and ic-ELISA are consistent in spiked samples and recovery experiments. Therefore, this method can quickly, efficiently, and reliably achieve high-throughput on-site rapid detection of illegally added CAN, OLM, and IRB in herbal beverages.

Targeting the High-Density Lipoprotein Proteome for the Treatment of Post-Acute Sequelae of SARS-CoV-2.

Here, we target the high-density lipoprotein (HDL) proteome in a case series of 16 patients with post-COVID-19 symptoms treated with HMG-Co-A reductase inhibitors (statin) plus angiotensin II type 1 receptor blockers (ARBs) for 6 weeks. Patients suffering from persistent symptoms (post-acute sequelae) after serologically confirmed SARS-CoV-2 infection (post-COVID-19 syndrome, PCS, n = 8) or following SARS-CoV-2 vaccination (PVS, n = 8) were included. Asymptomatic subjects with corresponding serological findings served as healthy controls (n = 8/8). HDL was isolated using dextran sulfate precipitation and the HDL proteome of all study participants was analyzed quantitatively by mass spectrometry. Clinical symptoms were assessed using questionnaires before and after therapy. The inflammatory potential of the patients' HDL proteome was addressed in human endothelial cells. The HDL proteome of patients with PCS and PVS showed no significant differences; however, compared to controls, the HDL from PVS/PCS patients displayed significant alterations involving hemoglobin, cytoskeletal proteins (MYL6, TLN1, PARVB, TPM4, FLNA), and amyloid precursor protein. Gene Ontology Biological Process (GOBP) enrichment analysis identified hemostasis, peptidase, and lipoprotein regulation pathways to be involved. Treatment of PVS/PCS patients with statins plus ARBs improved the patients' clinical symptoms. After therapy, three proteins were significantly increased (FAM3C, AT6AP2, ADAM10; FDR < 0.05) in the HDL proteome from patients with PVS/PCS. Exposure of human endothelial cells with the HDL proteome from treated PVS/PCS patients revealed reduced inflammatory cytokine and adhesion molecule expression. Thus, HDL proteome analysis from PVS/PCS patients enables a deeper insight into the underlying disease mechanisms, pointing to significant involvement in metabolic and signaling disturbances. Treatment with statins plus ARBs improved clinical symptoms and reduced the inflammatory potential of the HDL proteome. These observations may guide future therapeutic strategies for PVS/PCS patients.

Two-phase mechanism in the treatment of corneal stromal fibrosis with topical losartan.

Recent studies in rabbits and case reports in humans have demonstrated the efficacy of topical losartan in the treatment of corneal scarring fibrosis after a wide range of injuries, including chemical burns, infections, surgical complications, and some diseases. It is hypothesized that the effect of losartan on the fibrotic corneal stroma occurs through a two-phase process in which losartan first triggers the elimination of myofibroblasts by directing their apoptosis via inhibition of extracellular signal-regulated kinase (ERK)-mediated signal transduction, and possibly through signaling effects on the viability and development of corneal fibroblast and fibrocyte myofibroblast precursor cells. This first step likely occurs within a week or two in most corneas with fibrosis treated with topical losartan, but the medication must be continued for much longer until the epithelial basement membrane (EBM) is fully regenerated or new myofibroblasts will develop from precursor cells. Once the myofibroblasts are eliminated from the fibrotic stroma, corneal fibroblasts can migrate into the fibrotic tissue and reabsorb/reorganize the disordered extracellular matrix (ECM) previously produced by the myofibroblasts. This second stage is longer and more variable in different eyes of rabbits and humans, and accounts for most of the variability in the time it takes for the stromal opacity to be markedly reduced by topical losartan treatment. Eventually, keratocytes reemerge in the previously fibrotic stromal tissue to fine-tune the collagens and other ECM components and maintain the normal structure of the corneal stroma. The efficacy of losartan in the prevention and treatment of corneal fibrosis suggests that it acts as a surrogate for the EBM, by suppressing TGF beta-directed scarring of the wounded corneal stroma, until control over TGF beta action is re-established by a healed EBM, while also supporting regeneration of the EBM by allowing corneal fibroblasts to occupy the subepithelial stroma in the place of myofibroblasts.

CandeSpartan Study: Candesartan Spanish Response-prediction and Tolerability study in migraine.

INTRODUCTION: Effectiveness of candesartan in migraine prevention is supported by two randomized controlled trials. We aimed to assess the effectiveness, tolerability, and response predictors of candesartan in the preventive treatment of migraine. METHODS: Observational, multicenter, prospective cohort study. The 50%, 75% and 30% responder rates, between weeks 8-12 and 20-24, were compared with the baseline. Treatment emergent adverse effects were systematically evaluated. Response predictors were estimated by multivariate regression models. RESULTS: Eighty-six patients were included, 79.1% females, aged 39.5 (inter-quartile range [IQR] 26.3-50.3), with chronic migraine (43.0%), medication overuse headache (55.8%) and a median of two (inter-quartile range: 0.75-3) prior preventive treatments. At baseline patients had 14 (10-24) headache and 8 (5-11) migraine days per month. The 30%, 50% and 75% responder rates were 40%, 34.9% and 15.1% between weeks 8-12, and 48.8%, 36%, and 18.6% between weeks 20-24. Adverse effects were reported by 30 (34.9%) and 13 (15.1%) patients between weeks 0-12 and 12-24, leading to discontinuation in 15 (17.4%) patients. Chronic migraine, depression, headache days per month, medication overuse headache, and daily headache at baseline predicted the response between weeks 20-24. CONCLUSION: Candesartan effectiveness and tolerability in migraine prevention was in line with the clinical trials' efficacy.Trial registration: The study protocol is registered in ClinicalTrials.gov (NCT04138316).

Effects of the valsartan recall on heart failure patients: A nationwide analysis.

BACKGROUND: Valsartan is commonly used for cardiac conditions. In 2018, the Food and Drug Administration recalled generic valsartan due to the detection of impurities. Our objective was to determine if heart failure patients receiving valsartan at the recall date had a greater likelihood of unfavorable outcomes than patients using comparable antihypertensives. METHODS: We conducted a cohort study of Optum's de-identified Clinformatics® Datamart (July 2017-January 2019). Heart failure patients with commercial or Medicare Advantage insurance who received valsartan were compared to persons who received non-recalled angiotensin receptor blockers (ARBs) and angiotensin converting enzyme-inhibitors (ACE-Is) for 1 year prior and including the recall date. Outcomes included a composite for all-cause hospitalization, emergency department (ED), and urgent care (UC) use and a measure of cardiac events which included hospitalizations for acute myocardial infarction and hospitalizations/ED/UC visits for stroke/transient ischemic attack, heart failure or hypertension at 6-months post-recall. Cox proportional hazard models with propensity score weighting compared the risk of outcomes between groups. RESULTS: Of the 87 130 adherent patients, 15% were valsartan users and 85% were users of non-recalled ARBs/ACE-Is. Valsartan use was not associated with an increased risk of all-cause hospitalization/ED/UC use six-months post-recall (HR 1.00; 95% CI 0.96-1.03), compared with individuals taking non-recalled ARBs/ACE-Is. Similarly, cardiac events 6-months post-recall did not differ between individuals on valsartan and non-recalled ARBs/ACE-Is (HR 1.04; 95% CI 0.97-1.12). CONCLUSIONS: The valsartan recall did not affect short-term outcomes of heart failure patients. However, the recall potentially disrupted the medication regimens of patients, possibly straining the healthcare system.

The central renin-angiotensin system: A genetic pathway, functional decoding, and selective target engagement characterization in humans.

Accumulating evidence suggests that the brain renin angiotensin system (RAS) plays a pivotal role in the regulation of cognition and behavior as well as in the neuropathology of neurological and mental disorders. The angiotensin II type 1 receptor (AT1R) mediates most functional and neuropathology-relevant actions associated with the central RAS. However, an overarching comprehension to guide translation and utilize the therapeutic potential of the central RAS in humans is currently lacking. We conducted a comprehensive characterization of the RAS using an innovative combination of transcriptomic gene expression mapping, image-based behavioral decoding, and pre-registered randomized controlled discovery-replication pharmacological resting-state functional magnetic resonance imaging (fMRI) trials (N = 132) with a selective AT1R antagonist. The AT1R exhibited a particular dense expression in a subcortical network encompassing the thalamus, striatum, and amygdalo-hippocampal formation. Behavioral decoding of the AT1R gene expression brain map showed an association with memory, stress, reward, and motivational processes. Transient pharmacological blockade of the AT1R further decreased neural activity in subcortical systems characterized by a high AT1R expression, while increasing functional connectivity in the cortico-basal ganglia-thalamo-cortical circuitry. Effects of AT1R blockade on the network level were specifically associated with the transcriptomic signatures of the dopaminergic, opioid, acetylcholine, and corticotropin-releasing hormone signaling systems. The robustness of the results was supported in an independent pharmacological fMRI trial. These findings present a biologically informed comprehensive characterization of the central AT1R pathways and their functional relevance on the neural and behavioral level in humans.

Influence of angiotensin receptor and converting enzyme blockers therapy in the respiratory outcome of COVID-19 hospitalized patients / Influencia de la terapia con bloqueadores del receptor de angiotensina y de la enzima convertidora en el resultado respiratorio de pacientes hospitalizados por COVID-19

Objectives: COVID-19, caused by SARS-CoV-2, has spread around the world since 2019. In severe cases, COVID-19 can lead to hospitalization and death. Systemic arterial hypertension and other comorbidities are associated with serious COVID-19 infection. Literature is unclear whether antihypertensive therapy with angiotensin receptor blockers (ARBs) and angiotensin converting enzyme (ACE) inhibitors affect COVID-19 outcomes. We aim to assess whether ACEI/ARB therapy is a risk factor for worse respiratory outcomes related to COVID-19 in hospitalized patients. Methods: Retrospective study enrolling admitted COVID-19-diagnosed patients by RT-PCR at the Hospital Geral de Fortaleza, Brazil, during 2021. Patient medical records, sociodemographic, and clinical data were analyzed. Chest CT images were analyzed using CAD4COVID-CT/Thirona™ software. Results: A total of 294 patients took part in the study. A cut-off point of 66% of pulmonary involvement was found by ROC curve, with patients having higher risk of death and intubation and lower 60-day survival. Advanced age (RR 1.025, P=0.001) and intubation (RR 16.747, P<0.001) were significantly associated with a higher risk of death. Advanced age (RR 1.023, P=0.001) and the use of noninvasive ventilation (RR 1.548, P=0.037) were associated with a higher risk of intubation. Lung involvement (>66%) increased the risk of death by almost 2.5-fold (RR 2.439, P<0.001) and by more than 2.3-fold the risk of intubation (RR 2.317, P<0.001). Conclusions: Altogether, our findings suggest that ACEI or ARB therapy does not affect the risk of death and disease course during hospitalization.(AU)

Objetivos: La COVID-19, causada por el SARS-CoV-2, se ha extendido por todo el mundo desde 2019. En casos graves, la COVID-19 puede provocar hospitalización y muerte. La hipertensión arterial sistémica y otras comorbilidades se asocian con una infección grave por COVID-19. La literatura no está clara si la terapia antihipertensiva con bloqueadores de los receptores de angiotensina (BRA) e inhibidores de la enzima convertidora de angiotensina (ECA) afecta los resultados de la COVID-19. Nuestro objetivo fue evaluar si la terapia BRA/ECA es un factor de riesgo de peores resultados respiratorios relacionados con COVID-19 en pacientes hospitalizados. Métodos: Estudio retrospectivo que incluyó pacientes ingresados con diagnóstico de COVID-19 mediante RT-PCR en el Hospital General de Fortaleza, Brasil, durante 2021. Se analizaron las historias clínicas de los pacientes, datos sociodemográficos y clínicos. Las imágenes de TC de tórax se analizaron utilizando el software CAD4COVID-CT/ThironaTM. Resultados: Participaron en el estudio un total de 294 pacientes. Mediante curva ROC se encontró un punto de corte del 66% de afectación pulmonar, teniendo los pacientes mayor riesgo de muerte e intubación y menor supervivencia a 60 días. La edad avanzada (RR 1,025; P=0,001) y la intubación (RR 16,747; P<0,001) se asociaron significativamente con un mayor riesgo de muerte. La edad avanzada (RR 1,023; P=0,001) y el uso de ventilación no invasiva (RR 1,548; P=0,037) se asociaron con un mayor riesgo de intubación. La afectación pulmonar (>66%) aumentó el riesgo de muerte casi 2,5 veces (RR 2,439; P<0,001) y más de 2,3 veces el riesgo de intubación (RR 2,317, P<0,001). Conclusiones: Se concluyó que el tratamiento con BRA o ECA no afecta el riesgo de muerte y el curso de la enfermedad durante la hospitalización.(AU)

Three-Year Cardiovascular Outcomes of Telmisartan in Patients With Hypertension: An Electronic Health Record-Based Cohort Study.

BACKGROUND: Telmisartan exhibits superior efficacy in controlling 24-h blood pressure (BP) compared with other angiotensin receptor blockers (ARBs). However, data on its cardiovascular effects in patients with hypertension are limited. This study aimed to evaluate the cardiovascular outcomes in patients taking telmisartan compared to those taking other ARBs. METHODS: This multicenter retrospective study used data from the Korea University Medical Center database, built from electronic health records. A total of 19,247 patients taking two or more antihypertensive medications were identified. Patients prescribed telmisartan (telmisartan users) were compared with those prescribed an ARB other than telmisartan (other ARB users). The primary outcome was major adverse cardiac events (MACE), a composite of cardiovascular death, myocardial infarction, stroke, and hospitalizations due to heart failure. The adjusted outcomes were compared using 1:1 propensity score (PS) matching. RESULTS: Overall, 3,437 (17.9%) patients were telmisartan users. These patients were more likely to be younger and male and less likely to have a history of chronic kidney disease, dialysis, or heart failure. In the PS-matched cohort, BP control was similar in both groups; however, telmisartan users exhibited significantly lower visit-to-visit BP variability. The adjusted 3-year MACE rate was similar between telmisartan users (4.6%) and other ARB users (4.7%, log-rank P = 0.75), with comparable safety profiles. CONCLUSIONS: In real-world practice, telmisartan showed cardiovascular outcomes similar to those of other ARBs in patients with hypertension taking two or more antihypertensive drugs.

Systematic review: Clinical phenotypes, histopathological features and prognosis of enteropathy due to angiotensin II receptor blockers.

BACKGROUND: Although enteropathy due to angiotensin II receptor blockers (ARBs) has been known for over 10 years, clinicians' awareness of this condition is still low. AIMS: To systematically review the literature about clinical phenotypes, distribution of mucosal changes throughout the gastrointestinal tract and prognosis of enteropathy due to ARBs. METHODS: According to PRISMA guidelines, we searched PubMed and Embase for relevant articles up to November 6, 2023. We included full-text papers, letters, case reports and case series describing enteropathy due to ARBs. Patients were classified into subgroups based on endoscopic and histological findings of different regions of the gastrointestinal tract. The protocol was registered with Open Science Framework (https://doi.org/10.17605/OSF.IO/TK67C). RESULTS: We included 94 articles reporting 183 cases (101 female, mean age at diagnosis 69 ± 10 years). The clinical picture at diagnosis was characterised by severe diarrhoea (97%) and weight loss (84%, median -13 kg), leading to hospital admission in 167 (95%) patients. Olmesartan (90%) was most frequently implicated. Villous atrophy (VA) was reported in 164/183 (89%) patients. One hundred and nine had only VA, 12 had pan-gastrointestinal involvement, 23 had VA and gastric involvement and 19 had VA and colon involvement (predominantly microscopic colitis). Outcomes were reported for 178/183 (97%) patients, who all recovered clinically on ARBs withdrawal. Histological recovery occurred in all 96 patients with VA at baseline who underwent follow-up duodenal biopsy. CONCLUSIONS: Enteropathy due to ARBs is characterised by severe malabsorption often requiring hospital admission and can involve the entire gastrointestinal tract. Clinician awareness can lead to prompt diagnosis and excellent prognosis.

Effects of telmisartan on metabolic syndrome components: a comprehensive review.

Telmisartan is an antagonist of the angiotensin II receptor used in the management of hypertension (alone or in combination with other antihypertensive agents. It belongs to the drug class of angiotensin II receptor blockers (ARBs). Among drugs of this class, telmisartan shows particular pharmacologic properties, including a longer half-life than any other angiotensin II receptor blockers that bring higher and persistent antihypertensive activity. In hypertensive patients, telmisartan has superior efficacy than other antihypertensive drugs (losartan, valsartan, ramipril, atenolol, and perindopril) in controlling blood pressure, especially towards the end of the dosing interval. Telmisartan has a partial PPARγ-agonistic effect whilst does not have the safety concerns of full agonists of PPARγ receptors (thiazolidinediones). Moreover, telmisartan has an agonist activity on PPARα and PPARδ receptors and modulates the adipokine levels. Thus, telmisartan could be considered as a suitable alternative option, with multi-benefit for all components of metabolic syndrome including hypertension, diabetes mellitus, obesity, and hyperlipidemia. This review will highlight the role of telmisartan in metabolic syndrome and the main mechanisms of action of telmisartan are discussed and summarized. Many studies have demonstrated the useful properties of telmisartan in the prevention and improving of metabolic syndrome and this well-tolerated drug can be greatly proposed in the treatment of different components of metabolic syndrome. However, larger and long-duration studies are needed to confirm these findings in long-term observational studies and prospective trials and to determine the optimum dose of telmisartan in metabolic syndrome.

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker on oxidative stress and metabolism of elements in kidney of STZ-induced diabetic rats.

In diabetes, increased oxidative stress and impaired trace element metabolism play an important role in the pathogenesis of diabetic nephropathy. The objective of this research was to examine the outcomes of blocking the renin-angiotensin system, using either the angiotensin-converting enzyme inhibitor (ACEI), perindopril, or the angiotensin II type 1 (AT1) receptor blocker, irbesartan, on oxidative stress and trace element levels such as Zn, Mg, Cu, and Fe in the kidneys of diabetic rats that had been induced with streptozotocin. Thirty-two Wistar albino male rats were equally divided into four groups. The first group was used as a control. The second group of rats developed diabetes after receiving a single intraperitoneal dose of STZ. The third and fourth groups of rats had STZ-induced diabetes and received daily dosages of irbesartan (15 mg/kg b.w/day) and perindopril (6 mg/kg b.w/day) treatment, respectively. Biochemical analysis of the kidneys showed a distinct increase in oxidative stress, indicated by heightened levels of malondialdehyde (MDA) and decreased superoxide dismutase (SOD) activities, as well as reduced glutathione (GSH) levels in the kidneys of diabetic rats. In the kidneys of diabetic rats, the mean levels of Fe and Cu were found to be significantly higher than those of the control group. Additionally, the mean levels of Zn and Mg were significantly lower in the diabetic rats compared to the control rats. Both perindopril and irbesartan decreased significantly MDA content and increased SOD activities and GSH levels in the kidneys of rats with diabetes. The Zn and Mg concentrations in the kidneys of diabetic rats treated with perindopril and irbesartan were markedly higher than in untreated STZ-diabetic rats, while the Cu and Fe concentrations were significantly lower. The urinary excretion of rats treated with perindopril and irbesartan showed a pronounced increase in Cu levels, along with a significant reduction in Zn and Mg levels. Although diabetic rats demonstrated degenerative morphological alterations in their kidneys, both therapies also improved diabetes-induced histopathological modifications in the kidneys. Finally, the present results suggest that manipulating the levels of Zn, Mg, Cu, and Fe - either through ACE inhibition or by blocking AT1 receptors - could be advantageous in reducing lipid peroxidation and increasing antioxidant concentration in the kidneys of diabetic rats.

Unlocking the protective potential of the angiotensin type 2 receptor (AT2R) in acute lung injury and age-related pulmonary dysfunction.

Despite its known importance in the cardiovascular system, the specific role and impact of the angiotensin type 2 receptor (AT2R) in lung physiology and pathophysiology remain largely elusive. In this study, we highlight the distinct and specialized lung-specific roles of AT2R, primarily localized to an alveolar fibroblast subpopulation, in contrast to the angiotensin type 1 receptor (AT1R), which is almost exclusively expressed in lung pericytes. Evidence from our research demonstrates that the disruption of AT2R (AT2R-/y), is associated with a surge in oxidative stress and impaired lung permeability, which were further intensified by Hyperoxic Acute Lung Injury (HALI). With aging, AT2R-/y mice show an increase in oxidative stress, premature enlargement of airspaces, as well as increased mortality when exposed to hyperoxia as compared to age-matched WT mice. Our investigation into Losartan, an AT1R blocker, suggests that its primary HALI lung-protective effects are channeled through AT2R, as its protective benefits are absent in AT2R-/y mice. Importantly, a non-peptide AT2R agonist, Compound 21 (C21), successfully reverses lung oxidative stress and TGFß activation in wild-type (WT) mice exposed to HALI. These findings suggest a possible paradigm shift in the therapeutic approach for lung injury and age-associated pulmonary dysfunction, from targeting AT1R with angiotensin receptor blockers (ARBs) towards boosting the protective function of AT2R.

LC-MS/MS Investigation of nitrosamine impurities in certain Sartan group medicinal products available in Istanbul, Türkiye.

Nitrosamines (NAs) are molecules that include the nitroso functional group. In 2018, the US Food and Drug Administration (FDA) received its first report of NAs in pharmaceuticals. The fact that NA impurities are likely human carcinogens is relevant to these compounds. Furthermore, prolonged exposure to NA contaminants above safe limits may raise the risk of cancer. The goal of this article was to assess the amounts of six different NAs in Sartan group medicines purchased from formal pharmacies in Istanbul, Türkiye, using a validated LC-MS/MS assay. An LC-MS/MS-based analytical assay was undertaken. The separation was performed with a HR ODS 150mm×3.0mm and 5-analytical columns, providing effective separation of major peaks from NA impurities. In mobile phase A, formic acid was 0.10% in water, while in mobile phase B, formic acid was 0.10% in methanol. The flow rate was 0.4mL/minute, and the total runtime was 18minutes with the gradient elution mode. The validation was conducted in line with ISO/IEC 17025 requirements. Up to 100µg/L, linearity was determined using correlation coefficients (r2>0.995) for all NAs. The limit of quantification values for all NAs analyses were below 1.0µg/L. The mean recovery value obtained during the spike experiment was 95.18%, demonstrating the accuracy of the procedure. In addition, the accuracy was shown by a certified reference analysis, which yielded relative standard deviation and relative error values of 1.82% and 3.34%, respectively. During the intermediate precision testing, bias and relative standard deviation were 0.96 and 2.87%, respectively. Of the 75 study samples involving Sartan group medical products, no nitrosamine impurities were detected, demonstrating that pharmaceutical companies have adequate medication safety precautions in place in accordance with FDA and European Medicines Agency (EMA) regulations published to prevent NA contaminants in human medicinal products.

New Perspectives for Antihypertensive Sartans as Components of Co-crystals and Co-amorphous Solids with Improved Properties and Multipurpose Activity.

Sartans (angiotensin II receptor blockers, ARBs), drugs used in the treatment of hypertension, play a principal role in addressing the global health challenge of hypertension. In the past three years, their potential use has expanded to include the possibility of their application in the treatment of COVID-19 and neurodegenerative diseases (80 clinical studies worldwide). However, their therapeutic efficacy is limited by their poor solubility and bioavailability, prompting the need for innovative approaches to improve their pharmaceutical properties. This review discusses methods of co-crystallization and co-amorphization of sartans with nonpolymeric, low molecular, and stabilizing co-formers, as a promising strategy to synthesize new multipurpose drugs with enhanced pharmaceutical properties. The solid-state forms have demonstrated the potential to address the poor solubility limitations of conventional sartan formulations and offer new opportunities to develop dual-active drugs with broader therapeutic applications. The review includes an in-depth analysis of the co-crystal and co-amorphous forms of sartans, including their properties, possible applications, and the impact of synthetic methods on their pharmacokinetic properties. By shedding light on the solid forms of sartans, this article provides valuable insights into their potential as improved drug formulations. Moreover, this review may serve as a valuable resource for designing similar solid forms of sartans and other drugs, fostering further advances in pharmaceutical research and drug development.

Existence of Quantum Pharmacology in Sartans: Evidence in Isolated Rabbit Iliac Arteries.

Quantum pharmacology introduces theoretical models to describe the possibility of ultra-high dilutions to produce biological effects, which may help to explain the placebo effect observed in hypertensive clinical trials. To determine this within physiology and to evaluate novel ARBs, we tested the ability of known angiotensin II receptor blockers (ARBs) (candesartan and telmisartan) used to treat hypertension and other cardiovascular diseases, as well as novel ARBs (benzimidazole-N-biphenyl tetrazole (ACC519T), benzimidazole-bis-N,N'-biphenyl tetrazole (ACC519T(2)) and 4-butyl-N,N0-bis[[20-2Htetrazol-5-yl)biphenyl-4-yl]methyl)imidazolium bromide (BV6(K+)2), and nirmatrelvir (the active ingredient in Paxlovid) to modulate vascular contraction in iliac rings from healthy male New Zealand White rabbits in responses to various vasopressors (angiotensin A, angiotensin II and phenylephrine). Additionally, the hemodynamic effect of ACC519T and telmisartan on mean arterial pressure in conscious rabbits was determined, while the ex vivo ability of BV6(K+)2 to activate angiotensin-converting enzyme-2 (ACE2) was also investigated. We show that commercially available and novel ARBs can modulate contraction responses at ultra-high dilutions to different vasopressors. ACC519T produced a dose-dependent reduction in rabbit mean arterial pressure while BV6(K+)2 significantly increased ACE2 metabolism. The ability of ARBs to inhibit contraction responses even at ultra-low concentrations provides evidence of the existence of quantum pharmacology. Furthermore, the ability of ACC519T and BV6(K+)2 to modulate blood pressure and ACE2 activity, respectively, indicates their therapeutic potential against hypertension.

[Sartans in the treatment of arterial hypertension: focus on telmisartan and azilsartan. A review].

The activity of the renin-angiotensin-aldosterone system is one of the main pathogenetic mechanisms underlying cardiovascular diseases at all stages of the cardiovascular continuum. This article discusses the role of telmisartan and azilsartan as the most powerful sartans in modern cardiology. Azilsartan and especially telmisartan have a significant organoprotection and are superior to other antihypertensive drugs in terms of lowering blood pressure. However, the effect of azilsartan on hard endpoints has not been studied while the efficacy of telmisartan on hard endpoints has been evaluated in plenty clinical trials including 3 large randomized clinical trials with several thousand patients. The article also presents calculations showing the better cost-effectiveness of telmisartan compared to azilsartan.