Losartan ameliorates renal fibrosis by inhibiting tumor necrosis factor signal pathway.

Losartan is widely used in the treatment of chronic kidney disease (CKD) and has achieved good clinical efficacy, but its exact mechanism is not clear. We performed high-throughput sequencing (HTS) technology to screen the potential target of losartan in treating CKD. According to the HTS results, we found that the tumor necrosis factor (TNF) signal pathway was enriched. Therefore, we conducted in vivo and in vitro experiments to verify it. We found that TNF signal pathway was activated in both unilateral ureteral obstruction (UUO) rats and human proximal renal tubular epithelial cells (HK-2) treated with transforming growth factor-ß1 (TGF-ß1), while losartan can significantly inhibit TNF signal pathway as well as the expression of fibrosis related genes (such as COL-1, α-SMA and Vimentin). These data suggest that losartan may ameliorate renal fibrosis through modulating the TNF pathway.

Angiotensin II Directly Increases Endothelial Calcium and Nitric Oxide in Kidney and Brain Microvessels In Vivo With Reduced Efficacy in Hypertension.

BACKGROUND: The vasoconstrictor effects of angiotensin II via type 1 angiotensin II receptors in vascular smooth muscle cells are well established, but the direct effects of angiotensin II on vascular endothelial cells (VECs) in vivo and the mechanisms how VECs may mitigate angiotensin II-mediated vasoconstriction are not fully understood. The present study aimed to explore the molecular mechanisms and pathophysiological relevance of the direct actions of angiotensin II on VECs in kidney and brain microvessels in vivo. METHODS AND RESULTS: Changes in VEC intracellular calcium ([Ca2+]i) and nitric oxide (NO) production were visualized by intravital multiphoton microscopy of cadherin 5-Salsa6f mice or the endothelial uptake of NO-sensitive dye 4-amino-5-methylamino-2',7'-difluorofluorescein diacetate, respectively. Kidney fibrosis by unilateral ureteral obstruction and Ready-to-use adeno-associated virus expressing Mouse Renin 1 gene (Ren1-AAV) hypertension were used as disease models. Acute systemic angiotensin II injections triggered >4-fold increases in VEC [Ca2+]i in brain and kidney resistance arterioles and capillaries that were blocked by pretreatment with the type 1 angiotensin II receptor inhibitor losartan, but not by the type 2 angiotensin II receptor inhibitor PD123319. VEC responded to acute angiotensin II by increased NO production as indicated by >1.5-fold increase in 4-amino-5-methylamino-2',7'-difluorofluorescein diacetate fluorescence intensity. In mice with kidney fibrosis or hypertension, the angiotensin II-induced VEC [Ca2+]i and NO responses were significantly reduced, which was associated with more robust vasoconstrictions, VEC shedding, and microthrombi formation. CONCLUSIONS: The present study directly visualized angiotensin II-induced increases in VEC [Ca2+]i and NO production that serve to counterbalance agonist-induced vasoconstriction and maintain residual organ blood flow. These direct and endothelium-specific angiotensin II effects were blunted in disease conditions and linked to endothelial dysfunction and the development of vascular pathologies.

Effect of beta-blockers and angiotensin receptor blockers in reducing the aortic growth rate in children with bicuspid aortic valve-related aortopathy.

AIMS: The aim of this study is to evaluate the effect of beta-blockers and angiotensin receptor blockers in reducing the aortic growth rate in children with bicuspid aortic valve (BAV)-related aortopathy and ascending phenotype. METHODS: Consecutive paediatric patients (≤16 years) with BAV and ascending aorta (AsAo) dilation (z-score > 3) were enrolled in this observational retrospective cohort study. Patients receiving prophylactic treatment with either atenolol (0.5 to 1.0 mg/kg/daily) or losartan (0.7 to 1.4 mg/kg/daily) were compared with those who did not receive medical prophylaxis (control group). The primary outcome of interest was the annual rate of change in maximal AsAo diameter z-score in the treatment and control groups. RESULTS: From a cohort of 1005 patients, 120 (mean age 11.3 ± 4.5 years, 82% males) fulfilled the inclusion criteria and were included in the study. Patients in the treatment and control group had similar age, sex, family history of BAV, BAV morphology, and baseline AsAo diameter. During a median follow-up of 7.1 years (interquartile range 3.8-10.2), no differences were observed in the annual growth rate of aortic diameter z-score between patients on treatment and controls. The prevalence of aortic diameter progression was similar in the treatment and control groups, and treatment with atenolol or losartan was not associated with a lower rate of aortic disease progression. CONCLUSIONS: The findings revealed no significant difference in the annual aortic growth rate between treated and untreated patients. Larger cohort studies or, ideally, randomized clinical controlled trials are needed to validate these findings.

An angiotensin system inhibitor (losartan) potentiates antitumor efficacy of cisplatin in a murine model of non-small cell lung cancer.

Objective: Previous studies have demonstrated synergistic antitumor effects of angiotensin system inhibition (ASI) combined with cisplatin therapy in pancreatic cancer. This study examines whether or not synergistic antitumor effects occur with combination ASI and cisplatin treatment in lung cancer, and whether or not ASI-induced changes in epithelial-mesenchymal transition play a role in the mechanism of this antitumor phenomenon. Methods: A set of lung cancer cell lines representing a spectrum of epithelial to mesenchymal phenotypes were identified and characterized. Response of epithelial-mesenchymal transition markers to losartan was characterized. Cell culture models of lung cancer were next treated with losartan, cisplatin, or combination of both. Markers of epithelial-mesenchymal transition or surrogates of other signaling pathways (AKT, Stat3, and programmed death-ligand), and cell viability were quantified. Findings were confirmed in both allogenic and syngeneic in vivo murine flank tumor models. Results: Losartan treatment significantly increased E-cadherin and reduced vimentin in human lung cancer cell lines. Combination treatment with losartan and cisplatin enhanced epithelial markers, reduced mesenchymal markers, inhibited promesenchymal signaling mediators, and reduced cell viability. Findings were confirmed in vivo in a murine flank tumor model with transition from mesenchymal to epithelial phenotype and reduced tumor size following combination losartan and cisplatin treatment. Conclusions: Combination losartan and cisplatin treatment attenuates the epithelial-mesenchymal transition pathway and enhances the cytotoxic effect of chemotherapy with in vitro and in vivo models of non-small cell lung cancer. This study suggests an important role for ASI therapy in the treatment of lung cancer.

Role of angiotensin pathway and its target therapy to rescue from experimental cerebral malaria.

Cerebral malaria (CM) induced by Plasmodium falciparum is a devastating neurological complication that may lead the patient to coma and death. This study aimed to protect Plasmodium-infected C57BL6 mice from CM by targeting the angiotensin II type 1 (AT1) receptor, which is considered the common connecting link between hypertension and CM. In CM, AT-1 mediates blood-brain barrier (BBB) damage through the overexpression of ß-catenin. The AT-1-inhibiting drugs, such as irbesartan and losartan, were evaluated for the prevention of CM. The effectiveness of these drugs was determined by the down regulation of ß-catenin, TCF, LEF, ICAM-1, and VCAM-1 in the drug-treated groups. The expression levels of VE-cadherin and vinculin, essential for the maintenance of BBB integrity, were found to be restored in the drug-treated groups. The pro-inflammatory cytokine levels were decreased, and the anti-inflammatory cytokine levels increased with the treatment. As a major highlight, the mean survival time of treated mice was found to be increased even in the absence of treatment with an anti-malarial agent. The combination of irbesartan or losartan with the anti-malarial agent α/ß-arteether has contributed to an 80% cure rate, which is higher than the 60% cure rate observed with α/ß-arteether alone treatment.

Simple Determination of Bosentan in Plasma Samples by Reversed-Phase High-Performance Liquid Chromatography.

Background: In order to measure the plasma levels of Losartan and Bosentan, a sensitive Reverse Phase-High Performance Liquid Chromatography (RP-HPLC) technique was developed. Methods: To compare bioavailability, the Area Under the Curve (AUC), peak plasma concentration (Cmax), and time to Cmax (Tmax) were employed. The standard curve (150-2400 ng/ml) was linear (R2=0.999), relative errors were between 2.4 to 10.05% and the coefficient of variation (CV%) ranged from 1.52 to 10.88. A single dosage (test and reference) was used for the in vivo investigation, which involved 16 healthy individuals. Results: The AUC0-48, AUC0-, Cmax, and Tmax of the test and reference had no statistically significant differences. The Cmax and 95% confidence intervals of the ratio of Cmax of the two formulations were 0.93-0.96 and 97.6-135%, respectively. Conclusion: Therefore, it was established that generic Bosentan was equivalent to Bosentan from Actelion and that both medications could be regarded as equally effective in clinical settings. The blood level of Bosentan could be measured using this straightforward procedure in all hospital laboratories.

Combination of losartan with pirfenidone: a protective anti-fibrotic against pulmonary fibrosis induced by bleomycin in rats.

Pirfenidone (PFD), one acceptable medication for treating idiopathic pulmonary fibrosis (IPF), is not well tolerated by patients at full doses. Hence, employing of some approaches such as combination therapy may be applicable for increasing therapeutic efficacy of PFD. Losartan (LOS), an angiotensin II receptor antagonist, could be a suitable candidate for combination therapy because of its stabilizing effect on the pulmonary function of IPF patients. Therefore, this study aimed to investigate the effects of LOS in combination with PFD on bleomycin (BLM)-induced lung fibrosis in rats. BLM-exposed rats were treated with LOS alone or in combination with PFD. The edema, pathological changes, level of transforming growth factor-ß (TGF-ß1), collagen content, and oxidative stress parameters were assessed in the lung tissues. Following BLM exposure, the inflammatory response, collagen levels, and antioxidant markers in rat lung tissues were significantly improved by PFD, and these effects were improved by combination with LOS. The findings of this in vivo study suggest that the combined administration of PFD and LOS may provide more potent protection against IPF than single therapy through boosting its anti-inflammatory, anti-fibrotic, and anti-oxidant effects. These results hold promise in developing a more effective therapeutic strategy for treating of lung fibrosis.

Development of Losartan Orally Disintegrating Tablets by Direct Compression: a Cost-Effective Approach to Improve Paediatric Patient's Compliance.

The development of suitable dosage forms is essential for an effective pharmacological treatment in children. Orally disintegrating tablets (ODTs) are attractive dosage forms that avoid swallowing problems, ensure dosage accuracy and are easy to administer as they disintegrate in the oral cavity. This study aimed to develop ODTs containing losartan potassium (LP) for the treatment of arterial hypertension in children. The ODTs, produced by the cost-effective manufacturing process of direct compression, consisted of a mixture of diluent, superdisintegrant, glidant and lubricant. Five superdisintegrants (croscarmellose sodium, two grades of crospovidone, sodium starch glycolate and pregelatinized starch) were tested (at two concentrations), and combined with three diluents (mannitol, lactose and sorbitol). Thus, thirty formulations were evaluated based on disintegration time, hardness and friability. Two formulations, exhibiting the best results concerning disintegration time (< 30 s), hardness and friability (≤ 1.0%), were selected as the most promising ones for further evaluation. These ODTs presented favourable drug-excipient compatibility, tabletability and flow properties. The in vitro dissolution studies demonstrated 'very rapid' drug release. Preliminary stability studies highlighted the requirement of a protective packaging. All quality properties retained appropriate results after 12 months of storage in airtight containers. In conclusion, the ODTs were successfully developed and characterised, suggesting a potential means to accomplish a final prototype that enables an improvement in childhood arterial hypertension treatment.

Targeted and untargeted screening for impurities in losartan tablets marketed in Germany by means of liquid chromatography/high resolution mass spectrometry.

Technical advances in the field of quality analysis allow an increasingly deeper look into the impurity profile of drugs. The ability to detect unexpected impurities in addition to known impurities ensures the supply of high-quality drugs and can prevent recalls due to the detection of harmful unexpected impurities, as has happened recently with the N-nitrosamine and azido impurities in losartan (LOS) drug products. In the present study, the LC-MS/HRMS approach described by Backer et al. was applied to an even more complex system, being the investigation of 35 LOS drug products and combination preparations purchased in 2018 and 2022 in German pharmacies. The film-coated tablets were analysed by means of four LC-MS/HRMS method variants. For the separation a Zorbax RR StableBond C18 column (3.0 ×100 mm, particle size of 3.5 µm, pore size of 80 Å), a gradient elution and for mass spectrometric detection a qTOF mass spectrometer with electrospray ionization in positive and negative mode was used. An information-dependent acquisition method was applied for the acquisition of high-resolution mass spectrometry data. The combination of an untargeted and a targeted screening approach revealed the finding of eight impurities in total. Beside the five LOS related compounds, LOS impurity F, J, K, L, M, and related compound D from amlodipine besilate, LOS azide and an unknown derivative thereof were detected. Identification and structure elucidation, respectively, were successfully performed using in silico fragmentation. Differences in the impurity profiles of drug products from 2018 and 2022 could be observed. This study shows that broad screening approaches like this are applicable to the analysis of drug products and can be an important enhancement of the quality assurance of medicinal products.

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.

Losartan ameliorates renal fibrosis by inhibiting tumor necrosis factor signal pathway / Losartán mejora la fibrosis renal al inhibir la vía de señalización del factor de necrosis tumoral

Losartan is widely used in the treatment of chronic kidney disease (CKD) and has achieved good clinical efficacy, but its exact mechanism is not clear. We performed high-throughput sequencing (HTS) technology to screen the potential target of losartan in treating CKD. According to the HTS results, we found that the tumor necrosis factor (TNF) signal pathway was enriched. Therefore, we conducted in vivo and in vitro experiments to verify it. We found that TNF signal pathway was activated in both unilateral ureteral obstruction (UUO) rats and human proximal renal tubular epithelial cells (HK-2) treated with transforming growth factor-β1 (TGF-β1), while losartan can significantly inhibit TNF signal pathway as well as the expression of fibrosis related genes (such as COL-1, α-SMA and Vimentin). These data suggest that losartan may ameliorate renal fibrosis through modulating the TNF pathway.(AU)

El Losartán es ampliamente utilizado en el tratamiento de la enfermedad renal crónica (CKD) y ha logrado buenos resultados clínicos, pero su mecanismo exacto aún no está claro. Utilizamos la técnica de secuenciación de alto rendimiento (HTS) para detectar posibles dianas de losartán para el tratamiento de la CKD. Según los resultados de HTS, encontramos un enriquecimiento de la vía de señalización del factor de necrosis tumoral (TNF). Así, realizamos experimentos in vivo e in vitro para verificar esto. Encontramos que, tanto en ratas con obstrucción ureteral unilateral (uuo) como en células epiteliales tubulares renales proximal humanas (HK-2) tratadas con factor de crecimiento transformador β1 (TGF-β1), se activó la vía de señalización del TNF. El losartán inhibe significativamente la expresión de las vías de señalización del TNF y genes relacionados con la fibrosis, como COL-1, α-SMA y vicentin. Estos datos sugieren que el losartán puede mejorar la fibrosis renal regulando la vía del TNF.(AU)

Normalizing granuloma vasculature and matrix improves drug delivery and reduces bacterial burden in tuberculosis-infected rabbits.

Host-directed therapies (HDTs) represent an emerging approach for bacterial clearance during tuberculosis (TB) infection. While most HDTs are designed and implemented for immuno-modulation, other host targets-such as nonimmune stromal components found in pulmonary granulomas-may prove equally viable. Building on our previous work characterizing and normalizing the aberrant granuloma-associated vasculature, here we demonstrate that FDA-approved therapies (bevacizumab and losartan, respectively) can be repurposed as HDTs to normalize blood vessels and extracellular matrix (ECM), improve drug delivery, and reduce bacterial loads in TB granulomas. Granulomas feature an overabundance of ECM and compressed blood vessels, both of which are effectively reduced by losartan treatment in the rabbit model of TB. Combining both HDTs promotes secretion of proinflammatory cytokines and improves anti-TB drug delivery. Finally, alone and in combination with second-line antitubercular agents (moxifloxacin or bedaquiline), these HDTs significantly reduce bacterial burden. RNA sequencing analysis of HDT-treated lung and granuloma tissues implicates up-regulated antimicrobial peptide and proinflammatory gene expression by ciliated epithelial airway cells as a putative mechanism of the observed antitubercular benefits in the absence of chemotherapy. These findings demonstrate that bevacizumab and losartan are well-tolerated stroma-targeting HDTs, normalize the granuloma microenvironment, and improve TB outcomes, providing the rationale to clinically test this combination in TB patients.

The association between losartan potassium prescription and postoperative outcomes following total knee arthroplasty: A TriNetX analysis.

BACKGROUND: Total knee arthroplasty (TKA) is a common surgical procedure performed to alleviate pain and improve functional outcomes in patients with knee osteoarthritis and rheumatoid arthritis who have failed conservative treatments. Arthrofibrosis has been extensively studied due to its negative impact on TKA outcomes. Losartan, an angiotensin receptor blocker (ARB), has the potential to improve TKA outcomes by inhibiting TGF-ß and decreasing fibrosis. This study aims to analyze a large-scale, real-world healthcare database to investigate the association between losartan potassium prescription and postoperative outcomes such as readmissions, ED visits, and the need for MUA or revision TKA. HYPOTHESIS: Based on previous literature and the nature of ARBs, it is expected that the addition of losartan will aid in better outcomes for patients following a primary TKA. PATIENTS AND METHODS: In this retrospective observational study, the TriNetX Research Network (TriNetX) database was queried as of June 21, 2023. All patients who underwent a primary total knee arthroplasty (TKA) prior to June 21, 2022 were included. Patients were then divided into two cohorts by whether they had an active losartan potassium prescription within the year prior to their surgery to within 90days postoperatively. Patients were then propensity-matched to eliminate differences in demographics and comorbidities. RESULTS: Losartan TKA patients were 1.18 [OR: 0.85 (95% CI: 0.79-0.90), p<0.001] times less likely to be readmitted within 90days and were 1.15 (OR: 0.87 (95% CI: 0.79-0.96); p=0.009) times less likely to undergo a manipulation under anesthesia (MUA) within the 1-year postoperative period. There were no statistically significant differences in rates of emergency department (ED) visits at 90days postoperatively or revision TKAs at 1year postoperatively. DISCUSSION: In conclusion, patients with an active losartan prescription prior to TKA had a significantly lower likelihood of readmission within 90days and a lower likelihood of undergoing MUA within the 1-year postoperative period compared to patients not taking losartan. This presents an opportunity for further clinical investigation to explore the value of losartan in TKA. LEVEL OF EVIDENCE: III; an observational cohort study.

Ionizable Lipid Nanoparticle-Mediated TRAIL mRNA Delivery in the Tumor Microenvironment to Inhibit Colon Cancer Progression.

Introduction: Immunotherapy has revolutionized cancer treatment by harnessing the immune system to enhance antitumor responses while minimizing off-target effects. Among the promising cancer-specific therapies, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has attracted significant attention. Methods: Here, we developed an ionizable lipid nanoparticle (LNP) platform to deliver TRAIL mRNA (LNP-TRAIL) directly to the tumor microenvironment (TME) to induce tumor cell death. Our LNP-TRAIL was formulated via microfluidic mixing and the induction of tumor cell death was assessed in vitro. Next, we investigated the ability of LNP-TRAIL to inhibit colon cancer progression in vivo in combination with a TME normalization approach using Losartan (Los) or angiotensin 1-7 (Ang(1-7)) to reduce vascular compression and deposition of extracellular matrix in mice. Results: Our results demonstrated that LNP-TRAIL induced tumor cell death in vitro and effectively inhibited colon cancer progression in vivo, particularly when combined with TME normalization induced by treatment Los or Ang(1-7). In addition, potent tumor cell death as well as enhanced apoptosis and necrosis was found in the tumor tissue of a group treated with LNP-TRAIL combined with TME normalization. Discussion: Together, our data demonstrate the potential of the LNP to deliver TRAIL mRNA to the TME and to induce tumor cell death, especially when combined with TME normalization. Therefore, these findings provide important insights for the development of novel therapeutic strategies for the immunotherapy of solid tumors.

A design of experiment based RP-HPLC method for the simultaneous estimation of antihypertensive drugs with greenness assessment.

The correlation between blood pressure (BP) and cardiovascular risk has a continuous, positive, and linear pattern. Lowering high BP decreases the risk associated with cardiovascular disease. Chlorthalidone (CHD) and Losartan potassium (LOS) combination is used to treat hypertension. The analytical community was concerned with minimizing or reducing the use of toxic chemicals and solvents. Therefore, the current study aimed to develop a rapid, sensitive, and cost-effective green RP-HPLC method to determine CHD and LOS simultaneously in a short analysis of time. Method optimization was performed by Central composite design (CCD), the flow rate and the change of time were chosen as factors. Effective separation was conducted on Zorbax SB-C18 (4.6 mm × 150 mm, 5 µm) column by gradient mobile phase comprising phosphate buffer and ethanol flowing at 0.859 ml/min, and the wavelength detected at 230 nm. As per ICH criteria, the technique was proven to be precise, accurate, and linear over the concentration range of 4.3-8.1 µg/ml for CHD and 35-65 µg/ml for LOS. Furthermore, the method's greenness was examined by three different metrics, confirming that less toxic effect on the environment. Hence, the optimized approach proves to be eco-friendly, simple, and robust for the concurrent evaluation of CHD and LOS in pharmaceutical formulations.

A Comparative Study of the Safety and Efficacy Between Angiotensin-Converting Enzyme Inhibitors and Angiotensin Receptor Blockers on the Management of Hypertension: A Systematic Review.

Renin-angiotensin-aldosterone system (RAAS) inhibitors, including angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs), are commonly used in the management of hypertension. High blood pressure is a vital risk factor for cardiovascular disease. This study aims to establish any significant difference in using ACEIs and ARBs in managing hypertension. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to conduct this systematic review. We searched PubMed, MEDLINE, and ScienceDirect for articles published in the last 20 years (2003 to 2023). Our search was last done on the 27th of June, 2023. Following the initial search, 8,313 articles were found on PubMed. After screening the articles selected from the databases, 10 articles examining 1,621,445 patients were selected for the final study. Three articles were identified that compared ACEI and ARB in their capacity to lower blood pressure. Six articles compared both medications' capacity to reduce cardiovascular events and mortality. Five articles were identified that compared both classes of drugs for adverse effects. This study was made to determine whether or not there is a difference between the use of ACEIs and ARBs in the treatment of hypertension. The study showed that both ACEIs and ARBs are similar in their efficacy in lowering blood pressure. However, ACEI was revealed to be superior to ARB in reducing cardiovascular events and all-cause mortality. ARB was shown to be better tolerated by patients than ACEI.

Single nucleotide polymorphism (SNP) rs4291 of the angiotensin-converting enzyme (ACE) gene is associated with the response to losartan treatment in hypertensive patients.

Arterial hypertension is characterized by systolic pressure ≥ 140 mmHg and/or diastolic pressure ≥ 90 mmHg and its treatment consists of the use of antihypertensive drugs, as losartan and hydrochlorothiazide. Blood pressure is regulated by angiotensin-converting enzyme (ACE) and polymorphisms in the ACE gene are associated to a greater predisposition to hypertension and response to treatment. The aim of this study was to evaluate the association of genetic polymorphisms of ACE rs4363, rs4291 and rs4335 and the response to antihypertensive drugs in hypertensive patients from Ouro Preto/MG, Brazil. A case-control study was carried out with 87 hypertensive patients being treated with losartan and 75 with hydrochlorothiazide, who answered a questionnaire and had blood samples collected. Biochemical analyzes were performed on serum using UV/Vis spectrophotometry and identification of ACE variants rs4363, rs4291 and rs4335 was performed by real-time PCR using the TaqMan® system. Univariate logistic regression test was performed to compare categorical data in STATA 13.0 software. The results showed that there was an influence of ACE polymorphisms on the response to losartan, demonstrating that AT or TT genotypes of rs4291 were more frequent in the group of controlled AH (54.9%), indicating that these individuals are 2.8 times more likely to of being controlled AH (95% CI 1.12-6.80, p. =0.026) compared to those with AA genotype. In contrast, no influence of ACE polymorphisms on the response to hydrochlorothiazide was observed. In conclusion, the presence of the T allele of the rs4291 variant was associated to controled blood pressure when losartan was used as an antihypertensive agent. These results show the importance of pharmacogenetic studies to detect genetic characteristics, enabling therapeutic individuality and reducing costs for the healthcare system.

Physical exercise is essential for increasing ventricular contractility in hypertensive rats treated with losartan.

The treatment of hypertensive patients with losartan is very common. Despite the reduction in blood pressure, its effects on cardiac contractility and sympathetic autonomic drive are still controversial. In turn, aerobic physical training (APT) also presents an important therapeutic option, providing significant improvements in cardiovascular autonomic control, however little is known about its effects on cardiac contractility, especially when associated with losartan. Therefore, we investigated in spontaneously hypertensive rats (SHR) the effects of losartan and APT on cardiac hemodynamics and functionality, with emphasis on autonomic tonic balance and cardiac contractility. Sixty-four SHR (18 weeks old) were divided into four groups (N = 16): vehicle; vehicle submitted to APT through swimming for 12 weeks; treated with losartan (5 mg·kg-1·d-1) for 12 weeks; and treated with losartan associated with APT. The groups were submitted to cardiac morphological and functional analysis by echocardiography; double blockade of cardiac autonomic receptors with atropine and propranolol; and coronary bed reactivity and left ventricular contractility analyses by the Langendorff technique. APT improved functional parameters and autonomic balance by reducing sympathetic drive and/or increasing vagal drive. In contrast, it promoted a concentric remodeling of the left ventricle (LV). Treatment with losartan reduced sympathetic autonomic drive and cardiac morphological parameters, but there were no significant gains in cardiac functionality and contractility. When combined, the concentric remodeling of the LV to APT was abolished and gains in cardiac functionality and contractility were observed. Our findings suggest that the effects of losartan and APT are complementary and should be applied together in the treatment of hypertension. In spontaneously hypertensive rats, the combination of aerobic physical training with losartan treatment was crucial to greater blood pressure reductions and an increase in left ventricular contractility. Furthermore, losartan treatment prevented the concentric left ventricular remodeling caused by aerobic physical training.